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Sample records for type cheese produced

  1. Mold Flora of Traditional Cheeses Produced in Turkey

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    Musa Yalman

    2016-11-01

    Full Text Available In our country, there are many cheese types that are produced traditionally. Cheeses which produced from cows, sheep and goat milk that matured with spontaneous growth of molds present in livestock skins, pots and similar environments are among them. They are produced traditionally in Mediterrian, Central and Eastern Anatolia regions. Molds that grow spontaneously in cheeses could create public health risk because of their secondary metabolites. Penicillium spp. are the most isolated mold from these cheeses and Penicillium roqueforti is determined as the dominant species. Furthermore, Aspergillus, Alternaria, Mucor, Geotrichum, Cladosporium species have been isolated. It is very important to control the ripening conditions and starter strain selection since some strains were reported as mycotoxin producers. In this review, it has been tried to give general information about traditional production of mold-ripened cheese in Turkey and the mold flora found in traditional cheeses. In addition, public health risk of these cheeses is reported.

  2. Comparison of γ-aminobutyric acid and biogenic amine content of different types of ewe’s milk cheese produced in Sardinia, Italy

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    Gavina Manca

    2015-06-01

    Full Text Available The bioactive compounds γ-aminobutyric acid (GABA and biogenic amines (BA, together with protein-free amino acids, were measured by high-performance liquid chromatography in ewe’s milk cheeses produced in Sardinia with different technological traits. The study included three types of cheese: Pecorino Sardo PDO, Pecorino and Casu Marzu. Farmhouse Casu Marzu and Pecorino showed GABA content (maximum levels: 1001.3 and 378.1 mg 100 g–1 respectively that had never been found so high in cheese before, suggesting that these types of cheese present ideal conditions to produce GABA. These two types of cheese also showed high levels of BA (their total maximum levels were 1035.7 and 288.0 mg 100 g–1 respectively. Pearson correlation analysis detected significant correlation between GABA and the main BA present in the cheeses (tyramine, cadaverine and putrescine, suggesting that the factors affecting the production of GABA are the same as those influencing BA formation.

  3. Chemical composition and microbial load of cheese produced using ...

    African Journals Online (AJOL)

    Aframomum sceptrum) on the chemical composition and microbial load of cheese was evaluated in a Completely Randomized Design. Cheese produced with 1% bear berry (Aframomum sceptrum) had the highest (P < 0.05) crude protein content ...

  4. Staphylococcus aureus in locally produced white cheese in Tirana market

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    ELVIRA BELI; RENIS MAÇI; SONILA ÇOÇOLI; HALIT MEMOÇI

    2014-01-01

    Cheese has nutritional value, its consumption is very common in Albania, but is also excellent medium for bacterial growth, source of bacterial infection, particularly when it is produced from raw poor quality or unpasteurized milk. Microbial safety of cheeses may be enhanced by usage good quality raw milk, pasteurized milk, following GMP in aim to prevent cross-contamination. The aim of this study was to evaluate the presence and amount of Staphylococcus aureus in white cheeses, as an Albani...

  5. Socioeconomic diagnosis of cheese producers of Marajó, state of Pará, Brazil

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    Vitória Nazaré Costa Seixas

    2014-10-01

    Full Text Available The aim of this research was to diagnose the socioeconomic conditions of cheese producers from three municipalities of Marajó Island, Pará state, Brazil. Manufacture process, hygienic-sanitary conditions in handmade cheese production and its commercialization were some features analysed for both cream-type and butter-type cheeses. During the survey, conducted from March to September 2012 questionnaires were applied to ten Marajó’s cheese producers. The cheese fabrication was characterized as a handmade process, employing family labor, most over ten years of experience. The production has a small scale, uses rudimentary technologies, lacks proper infrastructure for the processing of the product and has unsatisfactory hygienic-sanitary conditions. Commercialization is mainly by direct sale on the ship that travels to Belém city, capital of Pará state. Interviewed producers showed good reception to knowledge that can improve quality of the product, but they need a better guidance. In this context, the transfer of information is essential to sustain the production of these cheeses and preserve local culture, contributing to the economic and social development of producers regions.

  6. Sensory quality of Camembert-type cheese: Relationship between starter cultures and ripening molds.

    Science.gov (United States)

    Galli, Bruno Domingues; Martin, José Guilherme Prado; da Silva, Paula Porrelli Moreira; Porto, Ernani; Spoto, Marta Helena Fillet

    2016-10-03

    Starter cultures and ripening molds used in the manufacture of moldy cheese aimed at obtaining characteristic flavors and textures considerably differ among dairy industries. Thus, the study of variables inherent to the process and their influence on sensory patterns in cheese can improve the standardization and control of the production process. The aim of this work was to study the influence of three different variables on the sensory quality of Camembert-type cheese: type of lactic bacteria, type of ripener molds and inoculation method. Batches of Camembert-type cheese were produced using O or DL-type mesophilic starter culture, ripened with Penicillium camemberti or Penicillium candidum and mold inoculation was made directly into the milk or by spraying. All batches were sensorially evaluated using Quantitative Descriptive Analysis (QDA) with panelists trained for various attributes. Among the combinations analyzed, those resulting in more typical Camembert-type cheese were those using O-type mesophilic starter culture and P. candidum maturation mold directly applied into the milk or sprayed and those using DL-type mesophilic starter and P. camemberti ripener mold applied by surface spraying. These results demonstrate, therefore, that the combination of different ripener molds, inoculation methods and starter cultures directly influences the sensory quality of Camembert-type cheese, modifying significantly its texture, appearance, aroma and taste. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Autochthonous cheeses of Bosnia and Herzegovina

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    Zlatan Sarić

    2003-04-01

    Full Text Available Despite the migration of people towards cities, autochthonous cheeses in Bosnia and Herzegovina survived. Technologies of these cheeses are simple and adapted to humble mountain limitations. Geographical occasions and rich mountain pastures created a certain participation of ewe's milk cheeses. Communicative isolation of hilly-mountain regions resulted in "closed" cheese production in small households. Autochthonous cheeses in Bosnia and Herzegovina have various origins. Different cheeses are produced in different parts of Bosnia and Herzegovina. There are : Travnički cheese, Masni (fat cheese, Presukača, Sirac, Livanjski cheese, Posni (lean cheese, "Suvi" (dry cheese or "Mješinski" full fat cheese matured in sheepskin bag, fresh sour milk cheese "Kiseli" and dried sour milk cheese "Kiseli", Zajednica, Basa, Kalenderovački cheese and goat's milk cheeses (Hard and White soft goat's milk cheese, "Zarica" and Urda. Besides above-mentioned types of cheese in Bosnia and Herzegovina some other autochthonous dairy products are produced: Kajmak (Cream, Maslo (Rendered butter and Zimsko kiselo mlijeko (Winter sour milk. The specificity in Bosnia and Herzegovina is that autochthonous dairy products are still mainly both produced and consumed in small rural households. Exceptions are Travnički cheese and Kajmak that are significantly sold at market. Only Livanjski cheese is manufactured as industry dairy product.

  8. Lecevacki cheese

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    Siniša Matutinović

    2007-04-01

    Full Text Available In this review traditional Croatian cheeses were described as well as their importance considering globalization and industrialization in food production. The most important property of traditional cheeses is their originality and origin of milk that is incorporated in those products. As the high profitability (high price of the products is very important it is necessary to conduct one of possible protections on European level. In that sense, hard cheeses from Adriatic and Dinara areas have significant potential due to the fact that high value raw material - sheep milk produced from breed with very extensively management using natural pasture with characteristic botanical composition consisting aromatic Mediteranean plants, is used in their production. This milk is characterized with high percentage of some chemical components, especially fat and protein. Considering that fact, this milk represents the best material especially for hard cheese production. In this paper the review of milk chemical composition of the most important Croatian sheep breeds which milk is used for production of hard cheeses, was performed. The review of basic technological parameters in production of hard traditional cheeses considering type, standardization and heat treatment of milk, renneting, curd cutting and drying, dimension, salting and ripening is represented. Characterization parameters of cheese, considering chemical and physical composition, biochemical changes, dominant microflora which dominates in technological production procedure and determines taste and odour of mature cheese, are shown. The basic characteristics and technology of Lecevacki cheese production was described too, as the most important traditional cheese from Split area surroundings. This cheese type was produced on family farms as well as on industrial level for some time. Its sensory characteristics are described in the paper.

  9. Quality evaluation of parmesan-type cheese: a chemometric approach

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    Henrique Jaster

    2014-03-01

    Full Text Available Parmesan-type cheeses are the most consumed special cheeses in Brazil. It is generally sold in retail shops, either grated or in wedge-shaped pieces, and its quality varies considerably, which is reflected directly in its price. There is lack of processing standardization and, since the ripening period is fundamental for the quality of this hard, semi-fat cooked cheese, this stage seems to be the thin line between low and high quality products. It is important to note that the Italian Parmegiano Reggiano is matured for a period of twelve months, as well as its rival Grana Padano, and this long ripening period causes changes making them gourmet, highly-valued cheeses. In the present study, twelve different Parmesan-type cheeses were purchased from the Brazilian retail market and evaluated for microbiological, physicochemical, and instrumental parameters. Heterogeneous quality was confirmed by microbiological problems detected in the samples and physicochemical composition that did not meet current Brazilian specifications. The use of principal component analysis and hierarchical cluster analysis made it possible to separate the samples into three distinct groups, mainly due to different acidity and moisture levels, water activity, and hardness values. The price per kg was also considered and was correlated with moisture, acidity, and texture.

  10. THE VARIATION OF SOME BIOCHEMICAL PARAMETERS FROM FRESH COW CHEESE CREAM TYPE WITH ADDED AROMATIC PLANTS

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    CRISTIANA DIACONESCU

    2007-10-01

    Full Text Available Recent advanced studies in the field of cheese fabrication technology include, amongother, the usage of aromatic plants and spices as a mean of improving theorganoleptic properties and as a mean of decreasing the lipidic peroxidationphenomenon. For this purpose, three types of fresh cow cheese produced by S.C.Marion Invest Trade 94 SRL, experimentally added with dill, savory and rosemary,were comparatively studied from a chemical point of view (pH, acidity, humidity, ashand a biochemical point of view(raw fat, total proteins, total cholesterol, acidphosphatase’s enzymatic activity, superoxide dismutase’s enzymatic activity, calciumcontent.From a chemical point of view, no significant differences appeared between the creamcheese types analyzed, excepting the pH( lower in the cheeses with dill and rosemaryFrom a biochemical point of view, two phenomenon can be observed: a significantdecrease of the acidic phosphatase activity in the cheeses with added dill androsemary ( positively correlating with the pH value and decreased values of the SODactivity in all cheese types.

  11. Cheese

    DEFF Research Database (Denmark)

    Gregersen, Vivi Raundahl; Lucey, J.A.

    2016-01-01

    The initial step in the manufacture of most cheese varieties involves enzymatic hydrolysis of one of the milk proteins, κ-casein. The enzyme involved is called rennet. During the primary stage, κ-casein is cleaved by rennet at the Phe105–Met106 bond, resulting in a reduction in both the net...

  12. Determination of some virulence factors of Candida spp. isolated from locally produced cheese in Diyala Governorate-Iraq

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    Suhail Jawdat Fadihl

    2017-03-01

    Full Text Available Locally produced cheese which called (Gibin Al arab is one of the most common dairy products in Iraq, it has an economic importance and great social value. This research aimed to identify yeast species from locally produced cheese (Gibin Al Arab in Diyala city which traditionally made and sold in markets of old town in Baquba, and study some of virulence factors (Esterase production, Phospholipase and Hemolytic production of yeasts belong to genus of Candida . All cheese samples showed contamination with varying number of yeast, total 88 yeast isolates obtained from 70 cheese samples, they were Geotrichum candidum(20.5%, Rhodotorela species(19.4%, Candida parapsilosis (18%, Candida albicans (13.6%, Candida  tropicalis (10.5%, Candida krusei (8%, Saccharomyces cerevisice (3.3% and mixed yeast (un identified at rate of (6.7%. Species of Candida formed half of the total isolates and the most prevalent isolate of Candida spp. was Candida parapsilosis .According to the results determining of  (Esterase production, Phospholipase and Hemolytic production as a virulence factors identifying Candida spp. these activities referred that all isolates of Candida spp. show one or more of these activities and that isolates of  medically important species Candida albicans were the most virulent isolates. this referred to the importance of take attention about consuming of such types of dairy products and need for applying more hygienic measures during handling, processing of milk and form of storage and/or selling of cheese.

  13. Metatranscriptome analysis of fungal strains Penicillium camemberti and Geotrichum candidum reveal cheese matrix breakdown and potential development of sensory properties of ripened Camembert-type cheese.

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    Lessard, Marie-Hélène; Viel, Catherine; Boyle, Brian; St-Gelais, Daniel; Labrie, Steve

    2014-03-26

    Camembert-type cheese ripening is driven mainly by fungal microflora including Geotrichum candidum and Penicillium camemberti. These species are major contributors to the texture and flavour of typical bloomy rind cheeses. Biochemical studies showed that G. candidum reduces bitterness, enhances sulphur flavors through amino acid catabolism and has an impact on rind texture, firmness and thickness, while P. camemberti is responsible for the white and bloomy aspect of the rind, and produces enzymes involved in proteolysis and lipolysis activities. However, very little is known about the genetic determinants that code for these activities and their expression profile over time during the ripening process. The metatranscriptome of an industrial Canadian Camembert-type cheese was studied at seven different sampling days over 77 days of ripening. A database called CamemBank01 was generated, containing a total of 1,060,019 sequence tags (reads) assembled in 7916 contigs. Sequence analysis revealed that 57% of the contigs could be affiliated to molds, 16% originated from yeasts, and 27% could not be identified. According to the functional annotation performed, the predominant processes during Camembert ripening include gene expression, energy-, carbohydrate-, organic acid-, lipid- and protein- metabolic processes, cell growth, and response to different stresses. Relative expression data showed that these functions occurred mostly in the first two weeks of the ripening period. These data provide further advances in our knowledge about the biological activities of the dominant ripening microflora of Camembert cheese and will help select biological markers to improve cheese quality assessment.

  14. Technological properties of bacteriocin-producing lactic acid bacteria isolated from Pico cheese an artisanal cow's milk cheese.

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    Ribeiro, S C; Coelho, M C; Todorov, S D; Franco, B D G M; Dapkevicius, M L E; Silva, C C G

    2014-03-01

    Evaluate technologically relevant properties from bacteriocin-producing strains to use as starter/adjunct cultures in cheese making. Eight isolates obtained from Pico cheese produced in Azores (Portugal) were found to produce bacteriocins against Listeria monocytogenes and three isolates against Clostridium perfringens. They were identified as Lactococcus lactis and Enterococcus faecalis and submitted to technological tests: growth at different conditions of temperature and salt, acid production, proteolysis, lipolysis, coexistence, enzymatic profile and autolytic capacity. Safety evaluation was performed by evaluating haemolytic, gelatinase and DNase activity, resistance to antibiotics and the presence of virulence genes. Some isolates presented good technological features such as high autolytic activity, acid and diacetyl production. Lactococcus lactis was negative for all virulence genes tested and inhibit the growth of all Lactic acid bacteria (LAB) isolates. Enterococci were positive for the presence of some virulence genes, but none of the isolates were classified as resistant to important antibiotics. The bacteriocin-producing Lc. lactis present good potential for application in food as adjunct culture in cheese production. The study also reveals good technological features for some Enterococcus isolates. Bacteriocin-producing strains presented important technological properties to be exploited as new adjunct culture for the dairy industry, influencing flavour development and improve safety. © 2013 The Society for Applied Microbiology.

  15. original article microbial contamination of locally produced cheese

    African Journals Online (AJOL)

    University of Technology, Ogbomoso, Nigeria. E-Mail: ... identifié fromage local (' wara ') comme un aliment à haut risque au Nigeria en raison du taux élevé de contamination, car ils sont ... automatically has been conferred to the soft cheese.

  16. Growth reduction of Listeria spp. caused by undefined industrial red smear cheese cultures and bacteriocin-producing Brevibacterium lines as evaluated in situ on soft cheese.

    Science.gov (United States)

    Eppert, I; Valdés-Stauber, N; Götz, H; Busse, M; Scherer, S

    1997-01-01

    The undefined microbial floras derived from the surface of ripe cheese which are used for the ripening of commercial red smear cheeses have a strong impact on the growth of Listeria spp. In some cases, these microbial consortia inhibit Listeria almost completely. From such undefined industrial cheese-ripening floras, linocin M18-producing (lin+) (N. Valdés-Stauber and S. Scherer, Appl. Environ. Microbiol. 60:3809-3814, 1994) and -nonproducing Brevibacterium linens strains were isolated and used as single-strain starter cultures on model red smear cheeses to evaluate their potential inhibitory effects on Listeria strains in situ. On cheeses ripened with lin+ strains, a growth reduction of L. ivanovii and L. monocytogenes of 1 to 2 log units was observed compared to cheeses ripened with lin strains. Linocin M18 activity was detected in cheeses ripened with lin+ strains but was not found in those ripened with lin strains. We suggest that production of linocin M18 contributes to the growth reduction of Listeria observed on model red smear cheeses but is unsufficient to explain the almost complete inhibition of Listeria caused by some undefined microbial floras derived from the surface of ripe cheeses. PMID:9406400

  17. Viability of the Lactobacillus rhamnosus HN001 probiotic strain in Swiss- and Dutch-type cheese and cheese-like products.

    Science.gov (United States)

    Cichosz, Grażyna; Aljewicz, Marek; Nalepa, Beata

    2014-06-01

    The objective of this study was to determine the viability of the probiotic Lactobacillus rhamnosus HN001 in Swiss-type and Dutch-type cheese and cheese-like products (milk fat is substituted by stearin fraction of palm fat) during manufacture, ripening, and storage. The use of the probiotic L. rhamnosus HN001 in Dutch-type cheese and cheese-like products significantly (P = 0.1) changed their chemical composition (protein and fat content) and an insignificant increase (approximately 1.6% in cheese-like products and approximately 0.3% in cheese) in yield. L. rhamnosus HN001 did not affect the rate of changes in the pH of ripened cheese and cheese-like products. A minor increase in probiotic counts was observed in initial stages of production and were partially removed with whey. Ripened cheese and cheese-like products were characterized by high survival rates of probiotic bacteria which exceeded 8 log CFU/g after ripening. An insignificant reduction in the number of viable probiotic cells was noted during storage of Swiss-type and Dutch-type cheese, whereas a significant increase in probiotic cell counts was observed in cheese-like products during storage. © 2014 Institute of Food Technologists®

  18. Quality and safety of artisan cheese produced in the serrana region of Santa Catarina

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    Giane Helenita Pontarolo

    2017-05-01

    Full Text Available The serrano artisan cheese produced from raw milk of dairy cattle is a typical product of high-altitude farms in the states of Santa Catarina and Rio Grande do Sul. However, marketing of the cheeses occurs illegally because they lack the minimum maturation period required for cheese produced from raw milk. The production of artisan cheeses is required to follow strict hygiene standards. This study aimed to test the quality and safety of cheeses that were produced in 31 farms of the Serrana region in Santa Catarina after 14 and 28 days of maturation. Coliform count was measured at 35 °C, and presence of other microorganisms such as Escherichia coli, Staphylococcus, Listeria spp., and Salmonella spp. were also tested. Fat and protein percentages, acidity, salt content, and humidity were also evaluated. Data were subjected to statistical analyses using the SAS® software. After 14 and 28 days of maturation, 74.19% (23/31 and 64.52% (20/31 of samples, respectively, showed higher numbers of coliforms at 35 °C than those permissible by law. Higher than permissible numbers of E. coli were observed in 45.16% (14/31 and 48.39% (15/31 of the samples analyzed after 14 and 28 days of maturation, respectively. Coagulase-positive staphylococci values above 103 CFU/g were observed in 54.84% (17/31 and 51.61% (16/31 of cheese samples after 14 and 28 days of maturation, respectively. Contamination with Salmonella spp. was not detected. However, Listeria monocytogenes serovar 4b was isolated in 3.23% (1/31 and 6.45% (2/31 of samples after 14 and 28 days of maturation, respectively. The results of humidity tests classified the cheese samples into three categories: low, medium, and high humidity. Semi fat cheeses were predominant in both maturation periods, although the samples were classified in thin, semi fat, and fat cheeses. The main variations in the compositions of analyzed samples occurred for salt and acidity levels. The maturation process has not proven

  19. Rheology of spreadable goat cheese made with autochthonous lactic cultures differing in their ability to produce exopolysaccharides

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    Frau Silvia Florencia

    2013-06-01

    Full Text Available The aim of this study was to compare the rheology of spreadable cheeses elaborated with autochthonous lactic starter cultures without the addition of exopolysaccharide-producing strain in the same starter with exopolysaccharide-producing strain. From a rheological standpoint, both samples were characterized as weak viscoelastic gels and pseudoplastic products. It was concluded that cheese made with exopolysaccharide-producing strain showed smaller G', G", and η* values over the range of frequencies studied and smaller critic stress values than the cheese without exopolysaccharide-producing strain. The results obtained indicate that cheeses without exopolysaccharide-producing strain need to be added with any texture enhancer product.

  20. CULTURAL IMPORTANCE OF CHEESE TYPE FOR KINGDOM PERNAMBUCANO

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    Neide Kazue Sakugawa Shinohara

    2015-03-01

    Full Text Available Cheese is one of the great achievements in the preservation of milk, using simple techniques and preserving important protein source in different food crops. Originally from the Netherlands, Edam cheese was introduced in Brazil in 1880 by the Portuguese colonizers, hence the name "kingdom." Currently, in the industrial production, the legislation determines that it is classified as "kingdom type ". Due to the high lipid and sodium content, this product that is most suitable in the composition of sandwiches, in sauces added to pasta and composition along with the desserts, these associations are part of the tradition, flavors and knowledge of Pernambuco’s cooking. A ball of Kingdom cheese is something that you have to give to families, especially in Christmas time and St. John, because it symbolizes the wish for happiness and prosperity in the northeastern important religious festivals calendar, where relatives and friends gather to celebrate the dates in question, putting on their tables this precious culinary heritage of Pernambuco.

  1. Manufacturing of Camembert type cheese made from goat's and cow's milk and their mixtures

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    Katarina Tonković

    2003-10-01

    Full Text Available The aim of this research was to examine the influence of goat's and cow's milk and their mixtures on the quality of the Camembert type cheese within 30 days of its preservation. Cheeses were made of a mixture of goat's and cow's milk in the following ratios: 0:100, 30:70, 50:50, 80:20 and 100:0. They were analysed on the twelfth and thirtieth day of the cheese production. The chemical analysis of milk for cheese production, as well as the chemical composition, pH and sensorial evaluation of cheeses have been determined. It has been proven that the chemical content and type of milk influencesm sensorial evaluation of cheeses and their shelf life. The analysed cheeses, after 12th day of processing, obtained better sensorial scores than those after the 30th day. Cheeses made of goat's milk have obtained the best sensorial evaluation, although their shelf life was shorter than the rest of the cheese samples made of cow's milk and mixtures of goat's and cow's milk. The chosen storage temperature (10-11 ºC was not adequate for Camembert cheeses. Therefore, in order to prolong the shelf life above the 30-day-period and to preserve sensorial properties of the cheeses, the temperature should be lower, i.e. 5 ºC.

  2. Yield of acid curd cheese produced from cow's milk from different lactation periods.

    Science.gov (United States)

    Salamończyk, Ewa; Młynek, Krzysztof; Guliński, Piotr; Zawadzka, Wiesława

    2017-01-01

    Milk production intensification has led in many countries, including Poland, to increased milk yields per cow. A higher milk yield resulted in changes in cow productivity, including extended lactations. There is a paucity of information on the quality of milk harvested during the last months of lactations exceed- ing 10 months. Production capacity cheese (“cheese expenditure”) is an important parameter of providing   a recovery as much as the possible components of the milk processed are dry substances, which in turn af- fects the economics of production. The aim of the study was to determine the influence of the lactation period (from standard lactation; extended lactation phase) on the performance of the acid curd cheese. the relation- ship between total protein content and acidity of fresh milk collected in two separate periods of lactation on the yield of acid cheese was also evaluated. The study included 1384 samples of milk collected from Polish Holstein-Friesian cows, the Black-White variety. The basic chemical composition of fresh milk and acid-curd cheese produced in the laboratory were analyzed. The cheese milk yield was evaluated on the basis of the quantity of the re- sulting curd mass. According to our estimates, under laboratory conditions an average of 100 kg of milk per cow in population produced an estimated 20.1 kg of curd cheese. The basic chemical composition of raw milk, which was diverse in terms of the period of lactation, showed a higher dry matter, fat and protein content in milk acquired during the extension phase of lactation compared to the milk of standard lactation. It has been found that the lower titratable acidity of fresh milk appeared with a higher yield of cheese curd. This difference was between 1.76 kg (with milk from cows milked during the extended lactation phase) to 2.72 kg from 100 kg of cheese milk (milk with the standard lactation). Thus, the optimum level of titratable acidity of milk for cheese yield is 6.0–7.5

  3. Heavy metals in cow's milk and cheese produced in areas irrigated with waste water in Puebla, Mexico.

    Science.gov (United States)

    Castro-González, Numa Pompilio; Calderón-Sánchez, Francisco; Castro de Jesús, Jair; Moreno-Rojas, Rafael; Tamariz-Flores, José V; Pérez-Sato, Marcos; Soní-Guillermo, Eutiquio

    2018-03-01

    The aim of this work was to determine Ni, Cr, Cu, Zn, Pb, and As levels in raw milk and Oaxaca and ranchero type cheeses, produced in areas irrigated with waste water from Puebla in Mexico. Milk results showed a mean Pb level of 0.03 mg kg -1 , which is above the maximum limit as set by Codex Alimentarius and the European Commission standards. For As a mean value of 0.12 mg kg -1 in milk was obtained. Mean As and Pb levels in milk were below the Mexican standard. Milk whey and ranchero cheese had mean Pb levels of 0.07 and 0.11 mg kg -1 , respectively. As was higher in Oaxaca and ranchero cheese at 0.17 and 0.16 mg kg -1 , respectively. It was concluded that cheeses made from cow's milk from areas irrigated with waste water are contaminated with Pb and As, which may represent a health risk.

  4. The effect of raw milk microbial flora on the sensory characteristics of salers-type cheeses

    OpenAIRE

    Callon, Cecile; Berdagué, Jean-Louis; Montel, Marie-Christine

    2005-01-01

    The sensory characteristics of Salers Protected Denomination of Origin raw-milk cheeses are linked to the biochemical composition of the raw material (milk) and to the resultant microbial community. To evaluate the influence of the microbial community on sensory characteristics, Salers-type cheeses were manufactured with the same pasteurized milk, reinoculated with 3 different microbial communities from 3 different filtrates from microfiltered milks. Each cheese was subjected to microbial cou...

  5. Camembert-type cheese ripening dynamics are changed by the properties of wrapping films.

    Science.gov (United States)

    Picque, D; Leclercq-Perlat, M N; Guillemin, H; Perret, B; Cattenoz, T; Provost, J J; Corrieu, G

    2010-12-01

    Four gas-permeable wrapping films exhibiting different degrees of water permeability (ranging from 1.6 to 500 g/m(2) per d) were tested to study their effect on soft-mold (Camembert-type) cheese-ripening dynamics compared with unwrapped cheeses. Twenty-three-day trials were performed in 2 laboratory-size (18L) respiratory-ripening cells under controlled temperature (6 ± 0.5°C), relative humidity (75 ± 2%), and carbon dioxide content (0.5 to 1%). The films allowed for a high degree of respiratory activity; no limitation in gas permeability was observed. The wide range of water permeability of the films led to considerable differences in cheese water loss (from 0.5 to 12% on d 23, compared with 15% for unwrapped cheeses), which appeared to be a key factor in controlling cheese-ripening progress. A new relationship between 2 important cheese-ripening descriptors (increase of the cheese core pH and increase of the cheese's creamy underrind thickness) was shown in relation to the water permeability of the wrapping film. High water losses (more than 10 to 12% on d 23) also were observed for unwrapped cheeses, leading to Camembert cheeses that were too dry and poorly ripened. On the other hand, low water losses (from 0.5 to 1% on d 23) led to over-ripening in the cheese underrind, which became runny as a result. Finally, water losses from around 3 to 6% on d 23 led to good ripening dynamics and the best cheese quality. This level of water loss appeared to be ideal in terms of cheese-wrapping film design. Copyright © 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. PRELIMINARY STUDY ON THE PREVALENCE OF COXIELLA BURNETII IN CHEESES PRODUCED IN SOUTHERN ITALY

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    Y.T.R. Proroga

    2011-08-01

    Full Text Available In this study the presence of Coxiella burnetii in cow, buffalo and small ruminants (sheep and goat cheeses produced in southern Italy has been evaluated with the aim to analyze the risk of infection for consumers. The survey was performed using molecular assays (Real-Time PCR to detect the presence of C. burnetii DNA. The samples have been furthermore tested with specific methods for species identification in milk and dairy products. C. burnetii has been detected in 75% of cow cheese samples, while in small ruminants and buffaloes diary products have been assessed at 45,9% and 23,9% respectively.

  7. CHARACTERIZATION OF MARAJÓ CHEESE, CREAM TYPE, IN TWO SEASONS:PHYSICOCHEMICAL AND MICROBIOLOGICAL ASPECTS

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    Vitória Nazaré Costa Seixas

    2014-04-01

    Full Text Available The Marajó cheese is an artisanal product derived from buffalo milk produced in Marajó Island-PA. The objectives of this research were to characterize through physicochemical and microbiological the Marajó cheese cream type and the effect of the season. The pH, the percentage of fat in dry matter and content of sodium chloride were attributes that proximate composition showed significant difference at 5% probability by Tukey test between the two seasons. Statistical difference was not found in the percentage of titratable acidity, moisture, fat, ash, total solids extract, proteins and water activity. As for microbiological characteristics, in general, there was an improvement in the results in the dry season as to coliformes and Staphylococcus aureus. However, the result of Escherichia coli has proved to be better in the rainy season, with all samples meeting the standard of legislation. On the count of aerobic mesophilic there was no difference between the periods of the year. The pathogens Listeria monocytogenes and Salmonella sp. were not detected in the Marajó cheese, cream type, within the four seasons of the year. The variability occurred in pH, %NaCl, GES and, between seasons, demonstrates the need for greater control of production aimed at standardizing and maintaining the identity of the product. Regarding the microbiological, standards were established in accordance with the current legislation.

  8. Properties of low-fat ultra-filtered cheeses produced with probiotic bacteria

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    Miočinović Jelena

    2014-01-01

    Full Text Available Probiotics are live microorganisms that in certain numbers may confer a health benefit on the host. Nowadays, there are many dairy products on the market, especially fermented milks, with probiotics, and their popularity is rising. The aim of this article was to investigate the viability of commercial probiotic bacteria (Lactobacillus acidophilus LAFTI®L10 i Bifidobacterium lactis LAFTI®B94, DSM, Netherland as well as their influence on the changes of composition, pH, proteolysis, microbiological status and sensory properties of low-fat ultra-filtered (UF cheeses within 2 months of ripening. Low-fat cast ultra-filtered (UF cheeses were produced according to the defined production procedure by mixing UF milk protein powder, skim milk and cream, without (control cheese A and with adjunct probiotic culture (cheese B. The compositional parameters (milk fat, proteins and dry-matter content, pH, proteolysis parameters (water soluble nitrogen, nitrogen soluble in 5% PTA, urea and SDS PAG electrophoresis, as well as the numbers of starters and probiotic bacteria, were determined during ripening. In addition, sensory evaluations of cheeses were performed throughout the ripening time. A significant influence of probiotic strains on the composition, pH and primary proteolysis of cheese during ripening was not found. The counts of commercial probiotic bacteria were maintained at high levels (>107 cfug-1 during the overall ripening period, as a prerequisite of their therapeutic effects. The adjunct probiotic cultures enhanced the rate of secondary proteolysis, which was shown by the significantly higher levels of PTAN/TN of experimental compared to the control cheeses. The sensory evaluation showed that the overall aroma of low-fat cheeses was remarkably improved by the addition of the probiotic cultures used. Based on the results it can be concluded that the low-fat UF cheeses differ in good dietetic and functional properties as well as very acceptable

  9. Controlled production of camembert-type cheeses: part III role of the ripening microflora on free fatty acid concentrations.

    Science.gov (United States)

    Leclercq-Perlat, Marie-Noëlle; Corrieu, Georges; Spinnler, Henry-Eric

    2007-05-01

    Phenomena generating FFAs, important flavour precursors, are significant in cheese ripening. In Camembert-like cheeses, it was intended to establish the relationships between the dynamics of FFA concentrations changes and the succession of ripening microflora during ripening. Experimental Camembert-type cheeses were prepared in duplicate from pasteurised milk inoculated with Kluyveromyces lactis, Geotrichum candidum, Penicillium camemberti, and Brevibacterium aurantiacum under aseptic conditions. For each cheese and each cheesy medium, concentrations of FFAs with odd-numbered carbons, except for 9:0 and 13:0, did not change over time. For long-chain FFAs, concentrations varied with the given cheese part (rind or core). K. lactis produced only short or medium-chain FFAs during its growth and had a minor influence on caproic, caprylic, capric, and lauric acids in comparison with G. candidum, the most lipolytic of the strains used here. It generated all short or medium-chain FFAs (4:0-12:0) during its exponential and slowdown growth periods and only long-chain ones (14:0-18:0) during its stationary phase. Pen. camemberti produced more long-chain FFAs (14:0-18:0) during its sporulation. Brev. aurantiacum did not generate any FFAs. The evidence of links between specific FFAs and the growth of a given microorganism is shown.

  10. Training small producers in Good Manufacturing Practices for the development of goat milk cheese

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    Adriana Noemí RAMÓN

    Full Text Available Abstract Training in Good Manufacturing Practices enhances quality during food processing. This paper evaluates GMP training aimed at improving the chemical, sensory and microbiological quality of goat milk cheese. We worked with 26 families that produce cheese as their main source of income. Semi-structured interviews and observation were conducted to select relevant topics. The manufacturing processes were compared and samples were analyzed before and after GMP training. We trained 80% of the producers. Before receiving training, they used to make cheese from raw milk in unhygienic conditions and with little equipment. The products obtained had bad sensory characteristics, cracks, eyes on the pasta, a high number of aerobic mesophilic bacteria and total coliforms. After training, the producers pasteurized the milk and standardized processing procedures, resulting in final products that contained higher protein and calcium content, suitable sensory characteristics, and a significant reduction in microorganisms, with total coliforms falling to ≤ 5.103 UFC/g. Therefore, this study shows that the manufacturing process and the chemical, sensory and microbiological parameters of goat milk cheese improved after GMP training.

  11. Interaction between sodium chloride and texture in semi-hard Danish cheese as affected by brining time, DL-starter culture, chymosin type and cheese ripening

    DEFF Research Database (Denmark)

    Akkerman, Marije; Søndergaard Kristensen, Lise; Jespersen, Lene

    2017-01-01

    Reduced NaCl in semi-hard cheeses greatly affects textural and sensory properties. The interaction between cheese NaCl concentration and texture was affected by brining time (0-28 h), . dl-starter cultures (C1, C2, and C3), chymosin type (bovine or camel), and ripening time (1-12 weeks). Cheese Na...... is reducible without significant textural impact using well-defined starter cultures and camel chymosin....

  12. Improving quality of some types of cheese by gamma irradiation

    International Nuclear Information System (INIS)

    Sallam, E.M.E.A

    2010-01-01

    The use of ionizing radiation as a food preservation technique has been recognized for many years as a means to reduce food losses, improve food safety, and extend shelf life. Furthermore, irradiation can be an effective way of reducing the incidence of food borne disease and treating a variety of potential problems in food supplies. The treatment of food with ionizing radiation is one of the most thoroughly researched techniques available to the food processing industry. In view of the afore mentioned the objective of this study were to study the effect of irradiation time and dose on Ras cheese quality, investigate the effect of irradiation after ripening on cheese quality and possibility of prolonging the shelf-life of Ras cheese, study the effect of irradiation dose on Kareish cheese quality and its shelf- life and to monitor the chemical, microbiological and sensory changes during ripening and storage of Ras and Kareish cheeses .The results of this study will be presented in three parts: Part I: Effect of irradiation dose and time on some properties of Ras cheese:Part II: Effect of irradiation on some properties during storage of ripened Ras cheese.Part III: Effect of irradiation on the quality and shelf-life of Kareish cheese: It could be concluded that irradiation caused a significant reduction of cheese ripening indices, and count of total viable,proteolytic, lipolytic bacteria and mould and yeast. Using irradiation doses of 3 and 4 kGy were able to stop the ripening factors and these safety dose were used to prevent the ripened Ras cheese irradiation of ripened Ras cheese has been prolonged the shelf-life of Ras cheese to about 32 months compared with control cheese, which showed only 18 months. The obtained results revealed that the best irradiation treatment was at the end of ripening period. Also safety irradiation of Kareish cheese has been prolonged the shelf-life of Kareish cheese to about 54 days compared with 12 days only control cheese.

  13. Characteristic and Quality and Food Safety of Regional Cheese Produced from Mixed Milk

    Directory of Open Access Journals (Sweden)

    Marcela Vyletělová-Klimešová

    2014-01-01

    Full Text Available There were cheeses produced from raw cow’s milk and from mixed milk compared. Mixed milk contained small ruminants’ milk (goat’s and ewe’s milk and cow’s milk in different proportions. There were technological, physical and health parameters, mineral composition, microbiological indicators and sensory quality evaluated. Cow’s milk, compared to mixed milk, contained markedly lower amounts of fat, protein, casein, total solids, solids non fat, urea and acetone and higher values of lactose, citric acid and free fatty acids and showed significantly lower values of somatic cell count. Mixed milk showed lower (better results for freezing point depression, markedly higher titration acidity and higher values ​​for Ca, Mg, K, P, Cu, Mn and Zn. The results of microbiological analyses confirmed good hygienic quality in terms of total count of mesophlic, psychrotrophic and thermoresistant bacteria and coliforms. Negative incidence of L. monocytogenes and mostly negative incidence of S. aureus are important results and confirmed high quality of raw material for cheese production. None of S. aureus strains were confirmed as MRSA. The results of sensory evaluation showed no significant differences between cheeses originated from cow’s milk and cheeses from mixed milk.

  14. Mixing sweet cream buttermilk with whole milk to produce cream cheese

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    Bahrami Masoud

    2015-12-01

    Full Text Available Buttermilk is an important by-product of the manufacture of butter. Sweet-cream buttermilk (SCBM is similar in composition to skim milk, except for its high phospholipid and milk fat globular membrane protein content. The main objective of this investigation was to produce optimum quality cream cheese by replacing whole milk with different proportions of SCBM (5, 10, 15, 20, 25, 30, 35, 40, 45, and 50%. Statistical analysis showed that there were significant differences (p < 0.05 between the chemical and organoleptic properties of the samples. As the percentage of SCBM increased, the chemical composition of total solids, fat, protein, fat in dry matter (FDM and ash of cheese milk decreased significantly, leading to a softer, moister curd. Samples prepared with more than 25% SCBM were not acceptable to the taste panel. The cream cheeses prepared using 25% and 30% SCBM had the highest yields. Total solids and FDM were strong predictors of cheese yield (r2 ≈ 0.589. The results also showed that the best range for replacement using SCBM is 20–25%.

  15. The effect of raw milk microbial flora on the sensory characteristics of Salers-type cheeses.

    Science.gov (United States)

    Callon, C; Berdagué, J L; Dufour, E; Montel, M C

    2005-11-01

    The sensory characteristics of Salers Protected Denomination of Origin raw-milk cheeses are linked to the biochemical composition of the raw material (milk) and to the resultant microbial community. To evaluate the influence of the microbial community on sensory characteristics, Salers-type cheeses were manufactured with the same pasteurized milk, reinoculated with 3 different microbial communities from 3 different filtrates from microfiltered milks. Each cheese was subjected to microbial counts (on selective media), biochemical tests, and volatile and sensory component analyses at different times of ripening. Adding different microbial communities to specimens of the same (biochemically identical) pasteurized milk lead to different sensory characteristics of the cheeses. Cheeses with fresh cream, hazelnut, and caramel attributes were opposed to those with fermented cream, chemical, and garlic flavors. The aromatic compounds identified (esters, acids, alcohols, and aldehydes) in these cheeses were quite similar. Nevertheless, one milk was distinguished by a higher content of acetoin, and lower 2-butanone and 3-methylpentanone concentrations. Over the production period of 1 mo, the different cheeses were characterized by the same balance of the microbial population assessed by microbial counts on different media. This was associated with the stability of some sensory attributes describing these cheeses. Nevertheless, there was no linear correlation between microbial flora data and sensory characteristics as measured in this study.

  16. Invited review: Microbial evolution in raw-milk, long-ripened cheeses produced using undefined natural whey starters.

    Science.gov (United States)

    Gatti, Monica; Bottari, Benedetta; Lazzi, Camilla; Neviani, Erasmo; Mucchetti, Germano

    2014-02-01

    The robustness of the starter culture during cheese fermentation is enhanced by the presence of a rich consortium of microbes. Natural starters are consortia of microbes undoubtedly richer than selected starters. Among natural starters, natural whey starters (NWS) are the most common cultures currently used to produce different varieties of cheeses. Undefined NWS are typically used for Italian cooked, long-ripened, extra-hard, raw milk cheeses, such as Parmigiano Reggiano and Grana Padano. Together with raw milk microbiota, NWS are responsible for most cheese characteristics. The microbial ecology of these 2 cheese varieties is based on a complex interaction among starter lactic acid bacteria (SLAB) and nonstarter lactic acid bacteria (NSLAB), which are characterized by their different abilities to grow in a changing substrate. This review aims to summarize the latest findings on Parmigiano Reggiano and Grana Padano to better understand the dynamics of SLAB, which mainly arise from NWS, and NSLAB, which mainly arise from raw milk, and their possible role in determining the characteristics of these cheeses. The review is presented in 4 main sections. The first summarizes the main microbiological and chemical properties of the ripened cheese as determined by cheese-making process variables, as these variables may affect microbial growth. The second describes the microbiota of raw milk as affected by specific milk treatments, from milking to the filling of the cheese milk vat. The third describes the microbiota of NWS, and the fourth reviews the knowledge available on microbial dynamics from curd to ripened cheese. As the dynamics and functionality of complex undefined NWS is one of the most important areas of focus in current food microbiology research, this review may serve as a good starting point for implementing future studies on microbial diversity and functionality of undefined cheese starter cultures. Copyright © 2014 American Dairy Science Association

  17. Characterization of volatile compounds produced by Lactobacillus helveticus strains in a hard cheese model.

    Science.gov (United States)

    Cuffia, Facundo; Bergamini, Carina V; Wolf, Irma V; Hynes, Erica R; Perotti, María C

    2018-01-01

    Starter cultures of Lactobacillus helveticus used in hard cooked cheeses play an important role in flavor development. In this work, we studied the capacity of three strains of L. helveticus, two autochthonous (Lh138 and Lh209) and one commercial (LhB02), to grow and to produce volatile compounds in a hard cheese extract. Bacterial counts, pH, profiles of organic acids, carbohydrates, and volatile compounds were analyzed during incubation of extracts for 14 days at 37 ℃. Lactobacilli populations were maintained at 10 6 CFU ml -1 for Lh138, while decreases of approx. 2 log orders were found for LhB02 and Lh209. Both Lh209 and LhB02 slightly increased the acetic acid content whereas mild increase in lactic acid was produced by Lh138. The patterns of volatiles were dependent on the strain which reflect their distinct enzymatic machineries: LhB02 and Lh209 produced a greater diversity of compounds, while Lh138 was the least producer strain. Extracts inoculated with LhB02 and Lh 209 were characterized by ketones, esters, alcohols, aldehydes, and acids, whereas in the extracts with Lh138 the main compounds belonged to aromatic, aldehydes, and ketones groups. Therefore, Lh209 and LhB02 could represent the best cheese starters to improve and intensify the flavor, and even a starter composed by combinations of LhB02 or Lh209 with Lh138 could also be a strategy to diversify cheese flavor.

  18. Effect of type of concentrated sweet cream buttermilk on the manufacture, yield, and functionality of pizza cheese.

    Science.gov (United States)

    Govindasamy-Lucey, S; Lin, T; Jaeggi, J J; Martinelli, C J; Johnson, M E; Lucey, J A

    2007-06-01

    Sweet cream buttermilk (SCB) is a rich source of phospholipids (PL). Most SCB is sold in a concentrated form. This study was conducted to determine if different concentration processes could affect the behavior of SCB as an ingredient in cheese. Sweet cream buttermilk was concentrated by 3 methods: cold ( pizza cheese was manufactured using the 3 different types of concentrated SCB as an ingredient in standardized milk. Cheesemilks of casein:fat ratio of 1.0 and final casein content approximately 2.7% were obtained by blending ultrafiltered (UF)-SCB retentate (19.9% solids), RO-SCB retentate (21.9% solids), or EVAP-SCB retentate (36.6% solids) with partially skimmed milk (11.2% solids) and cream (34.6% fat). Control milk (11.0% solids) was standardized by blending partially skimmed milk with cream. Cheese functionality was assessed using dynamic low-amplitude oscillatory rheology, UW Meltprofiler (degree of flow after heating to 60 degrees C), and performance of cheese on pizza. Initial trials with SCB-fortified cheeses resulted in approximately 4 to 5% higher moisture (51 to 52%) than control cheese (approximately 47%). In subsequent trials, procedures were altered to obtain similar moisture content in all cheeses. Fat recoveries were significantly lower in RO- and EVAP-SCB cheeses than in control or UF-SCB cheeses. Nitrogen recoveries were not significantly different but tended to be slightly lower in control cheeses than the various SCB cheeses. Total PL recovered in SCB cheeses ( approximately 32 to 36%) were lower than control ( approximately 41%), even though SCB is high in PL. From the rheology test, the loss tangent curves at temperatures > 40 degrees C increased as cheese aged up to a month and were significantly lower in SCB cheeses than the control, indicating lower meltability. Degree of flow in all the cheeses was similar regardless of the treatment used, and as cheese ripened, it increased for all cheeses. Trichloroacetic acid-soluble N levels were

  19. Attitudes towards the use of GMOs in food production and willingness to buy cheese produced using GMOs for respondents with and without tasting experience

    DEFF Research Database (Denmark)

    Grunert, Klaus G.; Bech-Larsen, Tino; Lähteenmäki, Lisa

    European consumers are sceptical towards genetically modified organisms (GMOs) in food production, and their willingness to buy such products is low. Previous research also shows that these attitudes are quite resistant to attempts to change them by giving additional information. The aim of the s......European consumers are sceptical towards genetically modified organisms (GMOs) in food production, and their willingness to buy such products is low. Previous research also shows that these attitudes are quite resistant to attempts to change them by giving additional information. The aim...... of the study was to investigate if actual sensory experience with a (purportedly) GMO-based food product would influence consumers' attitude towards the use of GMOs in food production. An experiment was conducted in which subjects in the experimental group tasted cheeses, one of which was labelled as 'produced...... using GMOs.' The cheeses were selected in a way that ensured that the subject had a sensory preference for the GMO cheese. A control group tasted cheeses that were unlabelled. After the tasting, subjects completed a conjoint analysis task about cheese, in which the type of starter culture used (GMO...

  20. Safety Evaluation of Enterocin Producer Enterococcus sp. Strains Isolated from Traditional Turkish Cheeses.

    Science.gov (United States)

    Avcı, Mine; Özden Tuncer, Banu

    2017-07-06

    The purpose of this study was to determine the antimicrobial activity and occurrence of bacteriocin structural genes in Enterococcus spp. isolated from different cheeses and also investigate some of their virulence factors. Enterococcus strains were isolated from 33 different cheeses. Enterococcus faecium (6 strains) and Enterococcus faecalis (5 strains) enterocin-producing strains were identified by 16S rDNA analyses. Structural genes entA, entB, entP and entX were detected in some isolates. Multiple enterocin structural genes were found in 7 strains. None of the tested enterococci demonstrated anyβ-haemolytic activity and only one strain had gelatinase activity. Six strains showed multiple antibiotic resistance patterns and in addition, vanA and several virulence genes were detected in many strains. Only E. faecalis MBE1-9 showed tyrosine decarboxylase activity and tdc gene was detected only in this strain.

  1. Study of β-Galactosidase Enzyme Activity Produced by Lactobacilli in Milk and Cheese

    Directory of Open Access Journals (Sweden)

    J. Nowroozi

    2008-04-01

    Full Text Available Background and objectiveLactose intolerance is a discomfort state that occurs in some people after ingestion of milk and it is due to insufficient amount of beta galactosidase in the human gut to digest lactose. The aim of this study was to observe the presence of beta galactosidase enzyme produced by isolated lactobacilli from milk and cheese. Methods In this descriptive study, milk and cheese samples with different brand were bought from different shops. Lactobacilli were identified by plating samples on MRS medium, Gram staining and standard biochemical methods. β-galactosidase production by bacteria was assessed by X-Gal and ONPG methods. β-galactosidase was also detected by SDS-PAGE. ResultsFourteen genus of lactobacillus were isolated From 50 samples. All of the bacteria produced green color colonies on X-Gal plates (but in different times that indicated the presence of enzyme in the bacteria. All isolated lactobacilli were shown β-galactosidase activity in ONPG test. The highest enzymatic activity was seen in one strain of Lactobacillus Delbrueckii (1966 Miller unit /ml. In some bacteria (37% a strong β-galactosidase band(116-kDa was seen by SDS-PAGE.ConclusionAddition of beta galactosidase containing lactobacilli as a probiotic agent to milk, cheese, and other dairy products could ameliorate lactose intolerance. Meanwhile X-gal and ONPG methods which are simple, rapid and cheap can be used instead of SDS-PAGE.Keywords: Lactobacillus, Beta-Galactosidase, Nitrophenylgalactosids

  2. POTENTIAL PRODUCTION OF CYCLOPIAZONIC ACID BY PENICILLIUM CAMEMBERTI STRAINS ISOLATED FROM CAMEMBERT TYPE CHEESE

    Directory of Open Access Journals (Sweden)

    Miroslava Císarová

    2012-10-01

    Full Text Available The aim of this study was to isolate the strains of fungi from Camembert type cheese, identify them and to test isolated strains of Penicillium camemberti for their ability to produce cyclopiazonic acid. The description of micro- and macromorphological features was used for identification of Penicillium camemberti strains. Strains were subsequently in vitro tested on their potential ability to produce mycotoxin cyclopiazonic acid (CPA. All of the 14 strains of Penicillium camemberti, which were obtained from 20 samples of Camembert type cheese, were cultivated 7, 14, 21, 27 and 30 days on CYA medium at 10±1°C, 15±1°C and 25±1°C in the dark. For determination of CPA production ability by P. camemberti isolates in vitro was TLC used. After 7 days of cultivation cyclopiazonic acid was produced only by 5 from 14 strains cultivated at all cultivation temperatures. After 14 and 21 days of cultivation was CPA produced by 6 strains at all of cultivation temperatures. After 27 and 30 days of cultivation was CPA identified in 7 strains cultivated at all temperatures of cultivation. The other strains also produced mycotoxin, however, not at each temperature. The most productive at all temperatures and after all days were 5 out of 14 tested strains (S9, S10, S13, S18 and S19. Strains S6 and S16 did not produce CPA at any temperature. The lowest production after all days of cultivation was found at 10±1 °C (44% and the highest at 25±1 °C (85%.

  3. Stochastic modelling of Listeria monocytogenes single cell growth in cottage cheese with mesophilic lactic acid bacteria from aroma producing cultures

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Christiansen, Lasse Engbo; Dalgaard, Paw

    2015-01-01

    . 2014. Modelling the effect of lactic acid bacteria from starter- and aroma culture on growth of Listeria monocytogenes in cottage cheese. International Journal of Food Microbiology. 188, 15-25]. Growth of L. monocytogenes single cells, using lag time distributions corresponding to three different......A stochastic model was developed for simultaneous growth of low numbers of Listeria monocytogenes and populations of lactic acid bacteria from the aroma producing cultures applied in cottage cheese. During more than two years, different batches of cottage cheese with aroma culture were analysed...

  4. Mexican unpasteurised fresh cheeses are contaminated with Salmonella spp., non-O157 Shiga toxin producing Escherichia coli and potential uropathogenic E. coli strains: A public health risk.

    Science.gov (United States)

    Guzman-Hernandez, Rosa; Contreras-Rodriguez, Araceli; Hernandez-Velez, Rosa; Perez-Martinez, Iza; Lopez-Merino, Ahide; Zaidi, Mussaret B; Estrada-Garcia, Teresa

    2016-11-21

    Fresh cheeses are a main garnish of Mexican food. Consumption of artisanal fresh cheeses is very common and most of them are made from unpasteurised cow milk. A total of 52 fresh unpasteurised cheeses of five different types were purchased from a variety of suppliers from Tabasco, Mexico. Using the most probable number method, 67% and 63% of samples were positive for faecal coliforms and E. coli, respectively; revealing their low microbiological quality. General hygienic conditions and practices of traditional cheese manufacturers were poor; most establishments had unclean cement floors, all lacked windows and doors screens, and none of the food-handlers wore aprons, surgical masks or bouffant caps. After analysing all E. coli isolates (121 strains) for the presence of 26 virulence genes, results showed that 9 (17%) samples were contaminated with diarrheagenic E. coli strains, 8 harboured non-O157 Shiga toxin producing E. coli (STEC), and one sample contained both STEC and diffusely adherent E. coli strains. All STEC strains carried the stx1 gene. Potential uropathogenic E. coli (UPEC) strains were isolated from 15 (29%) samples; the most frequent gene combination was fimA-agn43. Two samples were contaminated with Salmonella. The results demonstrated that unpasteurised fresh cheeses produced in Tabasco are of poor microbiological quality and may frequently harbour foodborne pathogens. Food safety authorities in Mexico need to conduct more rigorous surveillance of fresh cheeses. Furthermore, simple and inexpensive measures as establishing programs emphasizing good hand milking practices and hygienic manufacturing procedures may have a major effect on improving the microbiological quality of these food items. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Antibacterial activity of different formulations of cheese and whey produced with kefir grains

    Directory of Open Access Journals (Sweden)

    Simone Weschenfelder

    Full Text Available ABSTRACT The development of different products that confer health benefits on the population is a challenge for those who work with food. The aim of this study was to elaborate two formulations of kefir cheese (C1 and C2 and whey (W1, W2, and to evaluate their in situ antibacterial activity against microorganisms of interest in food. Pasteurized milk, powdered milk and kefir grains were used in preparing the products and their percentage composition was determined. C1, C2, W1 and W2 were contaminated with five different logarithmic fractions (A = 8log to E = 4log CFU/ml of Staphylococcus aureus (ATCC 25923 and Escherichia coli (ATCC 11229, with antibacterial activity assessed over 0, 24, 48 and 72 hours of exposure. The results demonstrated the antibacterial activity of kefir cheese and whey, especially after 24 hours. Escherichia coli was the most sensitive of the bacteria, with maximum antibacterial activity seen in the cheese at population densities D and E, and in the whey at densities B, C, D and E after 48 and 72 h, showing that the in situ antibacterial activity of foods produced with kefir grains tends to be lower when compared with studies in vitro. The greater the nutrient content of the food, the lower the antibacterial activity seen, probably due to the protective action that the nutrients confer on the microorganisms against bacteriocins and the metabolites from fermentation.

  6. Assessment of hygienic quality of some types of cheese sampled from retail outlets.

    Science.gov (United States)

    Prencipe, Vincenza; Migliorati, Giacomo; Matteucci, Osvaldo; Calistri, Paolo; Di Giannatale, Elisabetta

    2010-01-01

    The authors evaluated the prevalence of Listeria monocytogenes, Escherichia coli O157:H7, Salmonella spp. and staphylococcal enterotoxin, in 2,132 samples selected from six types of cheese on the basis of recorded consumption in Italy in 2004. In L. monocytogenes-positive samples the precise level of contamination was determined. To define the physical-chemical characteristics of the selected natural cheeses, the pH values, water activity and sodium chloride content were determined. The results suggest that blue and soft cheeses (Brie, Camembert, Gorgonzola and Taleggio) are more likely to be contaminated with L. monocytogenes. The mean prevalence of L. monocytogenes in the six types of cheese was 2.4% (from 0.2% in Asiago and Crescenza to 6.5% in Taleggio), with contamination levels of up to 460 MPN/g. No presence of Salmonella spp. and E. coli O157 was found in any sample. Staphylococcus enterotoxin was found in 0.6% of the samples examined. Physical and chemical parameter values confirmed that all types of cheese are considered capable of supporting the growth of L. monocytogenes. The study confirmed the need to apply effective control at production and sales levels to reduce the probability of contamination by L. monocytogenes. This micro-organism can attain high levels of contamination in food products, such as cheeses that have a long shelf-life when associated with difficulties of maintaining appropriate storage temperatures in both sales points and in the home.

  7. Assessment of hygienic quality of some types of cheese sampled from retail outlets

    Directory of Open Access Journals (Sweden)

    Elisabetta Di Giannatale

    2010-06-01

    Full Text Available The authors evaluated the prevalence of Listeria monocytogenes, Escherichia coli O157:H7, Salmonella spp. and Staphylococcus enterotoxin, in 2 132 samples selected from six types of cheese on the basis of recorded consumption in Italy in 2004. In L. monocytogenes-positive samples the precise level of contamination was determined. To define the physical-chemical characteristics of the selected natural cheeses, the pH values, water activity and sodium chloride content were determined. The results suggest that blue and soft cheeses (Brie, Camembert, Gorgonzola and Taleggio are more likely to be contaminated with L. monocytogenes. The mean prevalence of L. monocytogenes in the six types of cheese was 2.4% (from 0.2% in Asiago and Crescenza to 6.5% in Taleggio, with contamination levels of up to 460 MPN/g. No presence of Salmonella spp. and E. coli O157 was found in any sample. Staphylococcus enterotoxin was found in 0.6% of the samples examined. Physical and chemical parameter values confirmed that all types of cheese are considered capable of supporting the growth of L. monocytogenes. The study confirmed the need to apply effective control at production and sales levels to reduce the probability of contamination by L. monocytogenes. This micro-organism can attain high levels of contamination in food products, such as cheeses that have a long shelf-life when associated with difficulties of maintaining appropriate storage temperatures in both sales points and in the home.

  8. Evaluation of the functional food potential of bamirad (a ginger-spiced) cheese produced in the western highlands of cameroon

    International Nuclear Information System (INIS)

    Dung, M.S.; Anyangwe, F.F.; Anselme, K.

    2013-01-01

    In this study, cheese was modified to enhance its functional characteristics thereby encouraging its consumption. Consequently, a ginger-spiced cheese (Ramirad) was produced and the effects of feed supplementation with cheese on blood lipid profile were evaluated using 36 male Wistar rats in four groups. Total cholesterol, high-density lipoprotein (HDL) cholesterol, low-density lipoprotein (LDL) cholesterol and triacylglycerols were determined. There were significant (P<0.05) changes indicating: weekly increases of triacylglycerols for all treatments, higher total cholesterol for the 0.0 % ginger treatment, and a decline of low-density lipoprotein for 1.0 % ginger treatment. The LDL/HDL ratio was very low, indicating that this cheese is a functional food, a potential exploitable for the well-being of the consumer. (author)

  9. Metatranscriptome analysis of fungal strains Penicillium and Geotrichum reveal cheese matrix breakdown and potential development of sensory properties of ripened Camembert-type cheese

    OpenAIRE

    Lessard, Marie-Hélène; Viel, Catherine; Boyle, Brian; St-Gelais, Daniel; Labrie, Steve

    2014-01-01

    Background Camembert-type cheese ripening is driven mainly by fungal microflora including Geotrichum candidum and Penicillium camemberti. These species are major contributors to the texture and flavour of typical bloomy rind cheeses. Biochemical studies showed that G. candidum reduces bitterness, enhances sulphur flavors through amino acid catabolism and has an impact on rind texture, firmness and thickness, while P. camemberti is responsible for the white and bloomy aspect of the rind, and p...

  10. Selection, application and monitoring of Lactobacillus paracasei strains as adjunct cultures in the production of Gouda-type cheeses.

    Science.gov (United States)

    Van Hoorde, Koenraad; Van Leuven, Isabelle; Dirinck, Patrick; Heyndrickx, Marc; Coudijzer, Kathleen; Vandamme, Peter; Huys, Geert

    2010-12-15

    Raw milk cheeses have more intense flavours than cheeses made from pasteurized milk and harbour strains with potential adjunct properties. Two Lactobacillus paracasei strains, R-40926 and R-40937, were selected as potential adjunct cultures from a total of 734 isolates from good quality artisan raw milk Gouda-type cheeses on the basis of their prevalence in different cheese types and/or over several production batches, safety and technological parameters. Conventional culturing, isolation and identification and a combined PCR-DGGE approach using total cheese DNA extracts and DNA extracts obtained from culturable fractions were employed to monitor viability of the introduced adjuncts and their effect on the cheese microbiota. The control cheese made without adjuncts was dominated by members of the starter, i.e. Lactococcus lactis and Leuconostoc pseudomesenteroides. In the cheeses containing either R-40926 or R-40937, the respective adjuncts increased in number as ripening progressed indicating that both strains are well adapted to the cheese environment and can survive in a competitive environment in the presence of a commercial starter culture. Principal component analysis of cheese volatiles determined by steam distillation-extraction and gas chromatography-mass spectrometry could differentiate cheeses made with different concentrations of adjunct R-40926 from the control cheese, and these differences could be correlated to the proteolytic and lipolytic properties of this strain. Collectively, results from microbiological and metabolic analyses indicate that the screening procedure followed throughout this study was successful in delivering potential adjunct candidates to enrich or extend the flavour palette of artisan Gouda-type cheeses under more controlled conditions. Copyright © 2010 Elsevier B.V. All rights reserved.

  11. Thermal properties of selected cheeses samples

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    Monika BOŽIKOVÁ

    2016-02-01

    Full Text Available The thermophysical parameters of selected cheeses (processed cheese and half hard cheese are presented in the article. Cheese is a generic term for a diverse group of milk-based food products. Cheese is produced throughout the world in wide-ranging flavors, textures, and forms. Cheese goes during processing through the thermal and mechanical manipulation, so thermal properties are one of the most important. Knowledge about thermal parameters of cheeses could be used in the process of quality evaluation. Based on the presented facts thermal properties of selected cheeses which are produced by Slovak producers were measured. Theoretical part of article contains description of cheese and description of plane source method which was used for thermal parameters detection. Thermophysical parameters as thermal conductivity, thermal diffusivity and volume specific heat were measured during the temperature stabilisation. The results are presented as relations of thermophysical parameters to the temperature in temperature range from 13.5°C to 24°C. Every point of graphic relation was obtained as arithmetic average from measured values for the same temperature. Obtained results were statistically processed. Presented graphical relations were chosen according to the results of statistical evaluation and also according to the coefficients of determination for every relation. The results of thermal parameters are in good agreement with values measured by other authors for similar types of cheeses.

  12. Krcki cheese

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    Zvonimir Prpić

    2003-07-01

    Full Text Available Krčki cheese is autochthonous Croatian cheese from the island of Krk, which belongs to the group of hard, full-fat cheeses, produced from raw, thermally untreated sheep′s milk. Taking into consideration the fact that the last investigation of Krčki cheese was done in the middle of the last century, probably some changes in technology of Krčki cheese production have occurred since this time. Therefore, the objectives of this paper were investigate the quality of sheep′s milk for Krčki cheese production, the quality of whey (as the material for production of albumin cheese quargs and Krčki cheese, as well as the technology of Krčki cheese production on family farms on the island of Krk. Results of the composition and characteristics analyses of sheep′s milk for Krčki cheese production were as follows: milk fat 7.81%; proteins 5.59%; lactose 4.97%; total solids 19.04%; non-fat dry matter 11.06%; pH 6.66; titratable acidity 9.41 °SH, and freezing point –0.555 °C. Somatic cell count (SCC was 407 000 cells/ml and total bacterial count (cfu was 950 000/mL. Average composition of Krčki cheese was as follows: fat 37.38%; protein 23.24%; total solids 63.22%; moisture in solid non-fat 57.36%; fat in total solids 54.38%; salt 1.97%; pH 5.78; lactic acid content 1.216%; WSN/TN 10.15%, and TCASN/TN 6.28%. Microbiological analyses of Krčki cheese showed that only 55% of analysed samples were hygienically acceptable according to the Regulations of Microbial Standards for Foods (NN 46/94.. Therefore, the necessary modifications have to be introduced into technology of production of sheep′s milk and Krčki cheese in order to increase microbiological quality and to reduce variability in composition and quality of Krčki cheese between family farms. These are necessary for preparing the Krčki cheese for Protection Geographical Indication (PGI.

  13. Preliminary characterization of wild lactic acid bacteria and their abilities to produce flavour compounds in ripened model cheese system.

    Science.gov (United States)

    Randazzo, C L; De Luca, S; Todaro, A; Restuccia, C; Lanza, C M; Spagna, G; Caggia, C

    2007-08-01

    The aim of this work was to preliminary characterize wild lactic acid bacteria (LAB), previously isolated during artisanal Pecorino Siciliano (PS) cheese-making for technological and flavour formation abilities in a model cheese system. Twelve LAB were studied for the ability to grow at 10 and 45 degrees C, to coagulate and acidify both reconstituted skim milk and ewe's milk. Moreover, the capacity of the strains to generate aroma compounds was evaluated in a model cheese system at 30- and 60-day ripening. Flavour compounds were screened by sensory analysis and throughout gas chromatography (GC)-mass spectrometry (MS). Most of the strains were able to grow both at 10 and 45 degrees C and exhibited high ability to acidify and coagulate ewes' milk. Sensory evaluation revealed that the wild strains produced more significant flavour attributes than commercial strains in the 60-day-old model cheese system. GC-MS data confirmed the results of sensory evaluations and showed the ability of wild lactobacilli to generate key volatile compounds. Particularly, three wild lactobacilli strains, belonging to Lactobacillus casei, Lb. rhamnosus and Lb. plantarum species, generated both in 60- and 30-day-old model cheeses system, the 3-methyl butan(al)(ol) compound, which is associated with fruity taste. The present work preliminarily demonstrated that the technological and flavour formation abilities of the wild strains are strain-specific and that wild lactobacilli, which produced key flavour compounds during ripening, could be used as tailor-made starters. This study reports the technological characterization and flavour formation ability of wild LAB strains isolated from artisanal Pecorino cheese and highlights that the catabolic activities were highly strain dependent. Hence, wild lactobacilli could be selected as tailor-made starter cultures for the PS cheese manufacture.

  14. Screening of adjunct cultures and their application in ester formation in Camembert-type cheese.

    Science.gov (United States)

    Hong, Q; Liu, X M; Hang, F; Zhao, J X; Zhang, H; Chen, W

    2018-04-01

    The ethanol content and esterase and alcohol acyltransferase activities are the limiting factors in the synthesis of ethyl esters in Camembert-type cheeses. This study aimed to investigate the effects of alcohol, esterase and alcohol acyltransferase activities on ethyl ester formation in Camembert-type cheeses. Five experimental cheeses were prepared with three adjunct cultures with different enzyme activities and two levels of ethanol content (400 or 800 μg/g). The cheeses were aged for 4 weeks and analysed weekly for basic physicochemical, textural, volatile and sensory properties. The results showed that both the enzyme activity and ethanol content were limiting factors in the synthesis of ethyl esters in the Camembert-type cheeses. Variation in the esterase synthesis activity was observed among lactic acid bacteria, and the starter culture Lactococcus lactis MA 14 LYO distinguished itself through its high acidifying and esterase hydrolysis abilities. The addition of CCFM 12, a lactic acid bacteria strain with high esterase and alcohol acyltransferase activity, along with 400 or 800 μg/g of ethanol, notably enhanced the generation of ethyl esters and the corresponding fruity flavour, without causing dramatic changes in the basic physicochemical indices and microbial profile. In addition, cohesiveness was influenced by the addition of 400 and 800 μg/g of ethanol, and more resilience with 800 μg/g of ethanol had been found. The results showed that the addition of CCFM12 with 400 and 800 μg/g of ethanol may be applied in the production of Camembert cheese to enhance its fruity flavour. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Starter culture development for improving the flavour of Proosdij-type cheese

    NARCIS (Netherlands)

    Ayad, E.H.E.; Verheul, A.; Bruinenberg, P.; Wouters, J.T.M.; Smit, G.

    2003-01-01

    The use of the additional mesophilic strain B851, which has specific flavour forming abilities, was tested for improving the flavour development of a Proosdij-type cheese made with a combination of an acidifying mesophilic and an adjunct thermophilic culture. This strain was selected because of its

  16. ANOMALOUS BLUE COLOURING OF MOZZARELLA CHEESE INTENTIONALLY CONTAMINATED WITH PIGMENT PRODUCING STRAINS OF PSEUDOMONAS FLUORESCENS

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    P. Sechi

    2011-04-01

    Full Text Available In summer 2010 a large outbreak of anomalous blue coloration of mozzarella cheese was recorded in Italy and some northern European countries. Official laboratory analysis and health authorities linked the outbreak to the contamination of processing water with strains of Pseudomonas fluorescens, although several expert raised the question of how to unequivocally link the blue coloring to the presence of the micro-organism. In an attempt to set-up a method to determine whether a given Pseudomonas spp. strain is responsible of the defect, an in vitro system for the evaluation of blue colouring of mozzarella cheese intentionally contaminated with strains of Pseudomonas fluorescens. was developed The system is aimed to ascertain whether P. fluorescens strains, isolated from mozzarella cheese with anomalous blue coloration, are able to reproduce the blue coloration under controlled experimental condition. 96 trials of experimental inoculation of mozzarella cheese in different preservation liquids, were conducted using various suspension of Pseudomonas spp. (P. fluorescens ATCC 13525, P. fluorescens CFBP 3150, one P. fluorescens field strain isolated from blue-colored mozzarella cheese and P. aeruginosa ATCC 10145 as positive control at different concentrations and incubated at different temperatures. Growth curve of all Pseudomonas spp. strains tested demonstrated that after three days of incubation the concentration was generally higher than 106 CFU/g of mozzarella cheese incubated in Tryptic Soy Broth (TSB, and higher than 105 CFU/g of mozzarella cheese incubated in preservation liquid. All mozzarella cheeses inoculated with the field strain of Pseudomonas fluorescens showed the characteristic anomalous blue coloration, which is often associated with Pseudomonas fluorescens contamination of water used during mozzarella cheesemaking. With the proposed system, which enabled a considerable amount of samples to be analysed under controlled experimental

  17. CHARACTERISTICS OF THE TEPEQUE CHEESE FROM “LA TIERRA CALIENTE” OF THE STATE OF MICHOACÁN: A CHEESE PRODUCED IN AN INTENSIVE SILVOPASTORAL SYSTEM

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    A.D. Solís Méndez

    2013-08-01

    Full Text Available The objective of the present work is to describe the characteristics of the Tepeque cheese from “La Tierra Caliente” of the State of Michoacán, Mexico. Its region of origin, manufacturing process, physico-chemical and microbiological characteristics, were investigated. In addition the changes that occurred in the milk and cheese due to the introduction of a feeding system based on the use of an intensive silvo-pastoral system (ISPS were described. The methodological approach consisted of field visits for data collection, semi-structured interviews to farmers in order to know the milk production systems and the cheese elaboration process. The physical (pH and density and chemical characteristics (protein, fat, lactose, non fat solids and added water of the milk used to elaborate the Tepeque cheese were determined. For the cheese the protein, fat, salt, moisture and ash contents and the pH were determined. The microbiological characteristics were determined for both milk and cheese, these included presence of mesophilic bacteria coliforms bacteria, yeast, fungus, Listeria spp. and Staphylococcus aureus. The field study was carried out in 2010; it was divided in two experimental periods of six months each, named rainfall season and dry season. Fifteen milk-cheese producers were sampled, eight of them practice the traditional milk production systems and seven the ISPS. It was observed that the Tepeque cheese is a dairy product of excellent quality from the point of view of its main nutritional components, it is made with good quality milk too and it has a long history and great tradition that is older than 300 years. On the other hand, the cheese elaborated with milk from the ISPS had higher fat content (P0.05. Finally, it was observed that the sanitary characteristics of the milk and cheese were deficient in both systems; this problem is attenuated with the maturing process of cheese since as the cheese matures the number of

  18. Expression and release of proteolytic enzymes of Lactococcus lactis : ripening of UF-cheese

    NARCIS (Netherlands)

    Meijer, W.C.

    1997-01-01

    Semi-hard cheese types, such as Gouda, cannot be satisfactorily produced when using ultrafiltration technology. Although the cheese yield increases using this method, the higher financial return is completely lost by the (poor) quality of the cheese. The work described in this thesis is

  19. Contribution of natural milk culture to microbiota, safety and hygiene of raw milk cheese produced in alpine malga

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    Rosaria Lucchini

    2018-04-01

    Full Text Available Processing of alpine milk in malga farms is carried out under conditions that can favor contamination by coliforms, coagulase-positive staphylococci, or pathogens such as Listeria monocytogenes. With the aim to improve the hygienic characteristics and safety of cheese produced in four malga farms the use of lyophilized Natural Milk Culture prepared with selected strains was tested. Two cheesemaking tests were carried out in the same day always starting from the same milk: in the first case following the malga recipe that uses either Natural Whey Culture or without the addition of a starter, in the second one using a Natural Milk Culture. Cheesemaking were carried out in four malga farms located in the west area of Trentino region within the same week. For hygienic and safety evaluation, aerobic colony count, coagulase-positive staphylococci, Escherichia coli, staphylococcal toxins, Listeria monocytogenes , and Salmonella spp, pH and aw were determined in raw milk from evening and morning milking, curd in vat, curd after extraction and two months-ripened cheese. Pathogens or toxins, high values of coagulase- positive staphylococci and E. coli were not found in cheese samples. However, in the curd coagulase-positive staphylococci reached values almost of 5 Log CFU/g in the two malga without starter cultures. The use of Natural Milk Culture reduced E. coli counts. In addition, DNA was extracted from cheese samples and from Natural Milk Culture and the composition of the microbial community determined by Next Generation Sequencing method. The determination of cheese microbial communities demonstrated that the use of Natural Milk Culture exerted different effects in the different malga, in any case preserving bacterial biodiversity.

  20. Use of cold microfiltration retentates produced with polymeric membranes for standardization of milks for manufacture of pizza cheese.

    Science.gov (United States)

    Govindasamy-Lucey, S; Jaeggi, J J; Johnson, M E; Wang, T; Lucey, J A

    2007-10-01

    Pizza cheese was manufactured with milk (12.1% total solids, 3.1% casein, 3.1% fat) standardized with microfiltered (MF) and diafiltered retentates. Polymeric, spiral-wound MF membranes were used to process cold (pizza. Nitrogen recoveries were significantly higher in MF standardized cheeses. Fat recoveries were higher in the pH6.3MF cheese than the control or pH6.4MF cheese. Moisture-adjusted cheese yield was significantly higher in the 2 MF-fortified cheeses compared with the control cheese. Maximum loss tangent (LT(max)) values were not significantly different among the 3 cheeses, suggesting that these cheeses had similar meltability. The LT(max) values increased during ripening. The temperature at which the LT(max) was observed was highest in control cheese and was lower in the pH6.3MF cheese than in the pH6.4MF cheese. The temperature of the LT(max) decreased with age for all 3 cheeses. Values of 12% trichloroacetic acid soluble nitrogen levels were similar in all cheeses. Performance on pizza was similar for all cheeses. The use of MF retentates derived with polymeric membranes was successful in increasing cheese yield, and cheese quality was similar in the control and MF standardized cheeses.

  1. Production of Volatile Compounds in Reconstituted Milk Reduced-Fat Cheese and the Physicochemical Properties as Affected by Exopolysaccharide-Producing Strain

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    Weijun Wang

    2012-12-01

    Full Text Available The application of the exopolysaccharide-producing strains for improving the texture and technical properties of reduced-fat cheese looks very promising. Streptococcus thermophilus TM11 was evaluated for production of reduced-fat cheese using reconstituted milk powder (CRMP. The physicochemical analysis of fresh and stored cheeses showed that this strain slightly increased moisture content resulting in cheese with higher yield and lower protein content compared to the direct acidified cheese. The volatiles of cheese were determined by SPME and GC equipped with a mass spectrometer. The results indicated that the major compounds included aldehydes, ketones and acids, whereas, alcohols and branched-chain aldehydes that contribute to exciting and harsh flavors were not found in CRMP. By the textural profile analysis, we found the cheese made with S. thermophilus TM11 had lower cohesiveness, resilience and higher adhesiveness than the direct acidified cheese, and had similar hardness. Further, S. thermophilus TM11 greatly changed the protein matrix with more opened cavities according to observation by scanning electron microscopy. Consequently, use of S. thermophilus TM11 could endow CRMP with the novel and suitable flavor properties and improved texture quality.

  2. Dynamics of Penicillium camemberti growth quantified by real-time PCR on Camembert-type cheeses under different conditions of temperature and relative humidity.

    Science.gov (United States)

    Leclercq-Perlat, Marie-Noëlle; Picque, Daniel; Martin Del Campo Barba, Sandra Teresita; Monnet, Christophe

    2013-06-01

    Penicillium camemberti plays a major role in the flavor and appearance of Camembert-type cheeses. However, little is known about its mycelium growth kinetics during ripening. We monitored the growth of P. camemberti mycelium in Camembert-type cheeses using real-time PCR in 4 ripening runs, performed at 2 temperatures (8 and 16°C) and 2 relative humidities (88 and 98%). These findings were compared with P. camemberti quantification by spore concentration. During the first phase, the mycelium grew but no spores were produced, regardless of the ripening conditions. During the second phase, which began when lactose was depleted, the concentration of spores increased, especially in the cheeses ripened at 16°C. Sporulation was associated with a large decrease in the mycelial concentration in the cheeses ripened at 16°C and 98% relative humidity. It was hypothesized that lactose is the main energy source for the growth of P. camemberti mycelium at the beginning of ripening and that its depletion would trigger stress, resulting in sporulation. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  3. Modeling of Camembert-type cheese mass loss in a ripening chamber: main biological and physical phenomena.

    Science.gov (United States)

    Hélias, A; Mirade, P-S; Corrieu, G

    2007-11-01

    A model of the mass loss of Camembert-type cheese was established with data obtained from 2 experimental ripening trials carried out in 2 pilot ripening chambers. During these experiments, a cheese was continuously weighed and the relative humidity, temperature, oxygen, and carbon dioxide concentrations in the ripening chamber were recorded online. The aim was to establish a simple but accurate model that would predict cheese mass changes according to available online measurements. The main hypotheses were that 1) the cheese water activity was constant during ripening, 2) the respiratory activity of the microflora played a major role by inducing heat production, combined with important water evaporation, 3) the temperature gradient existing inside the cheese was negligible, and the limiting phenomenon was the convective transfer. The water activity and the specific heat of the cheeses were assessed by offline measurements. The others parameters in the model were obtained from the literature. This dynamic model was built with 2 state variables: the cheese mass and the surface temperature of the cheese. In this way, only the heat transfer coefficient had to be fitted, and it was strongly determined by the airflow characteristics close to the cheeses. Model efficiency was illustrated by comparing the estimated and measured mass and the mass loss rate for the 2 studied runs; the relative errors were less than 1.9 and 3.2% for the mass loss and the mass loss rate, respectively. The dynamic effects of special events, such as room defrosting or changes in chamber relative humidity, were well described by the model, especially in terms of kinetics (mass loss rates).

  4. Controlled production of Camembert-type cheeses. Part II. Changes in the concentration of the more volatile compounds.

    Science.gov (United States)

    Leclercq-Perlat, Marie-Noëlle; Latrille, Eric; Corrieu, Georges; Spinnler, Henry-Eric

    2004-08-01

    Flavour generation in cheese is a major aspect of ripening. In order to enhance aromatic qualities it is necessary to better understand the chemical and microbiological changes. Experimental Camembert-type cheeses were prepared in duplicate from pasteurized milk inoculated with Kluyveromyces lactis, Geotrichum candidum, Penicillium camemberti and Brevibacterium linens under aseptic conditions. Two replicates performed under controlled conditions of temperature (12 degrees C), relative humidity (95 +/- 2%), and atmosphere showed similar ripening characteristics. The evolutions of metabolite concentrations were studied during ripening. The volatile components were extracted by dynamic headspace extraction, separated and quantified by gas chromatography and identified by mass spectrometry. For each cheese the volatile concentrations varied with the part considered (rind or core). Except for ethyl acetate and 2-pentanone, the volatile quantities observed were higher than their perception thresholds. The flavour component production was best correlated with the starter strains. During the first 10 days the ester formations (ethyl, butyl and isoamyl acetates) were associated with the concentrations of K. lactis and G. candidum. The rind quantity of esters was lower than that observed in core probably due to (1) a diffusion from the core to the surface and (2) evaporation from the surface to the chamber atmosphere. G. candidum and Brev. linens association produced 3 methyl butanol and methyl 3-butanal from leucine, respectively. DMDS came from the methionine catabolism due to Brev. linens. Styrene production was attributed to Pen. camemberti. 2-Pentanone evolution was associated with Pen. camemberti spores and G. candidum. 2-Heptanone changes were not directly related to flora activities while 2-octanone production was essentially due to G. candidum. This study also demonstrates the determining role of volatile component diffusion.

  5. Decline in Mycobacterium bovis and Brucella abortus populations during the maturation of experimentally contaminated parmesan-type cheese

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    Karina Ramirez Starikoff

    2016-11-01

    Full Text Available Brazilian legislation allows the manufacture of raw milk cheese with a maturation exceeding 60 days at room temperature above 5°C, but there is a lack of solid scientific evidence on the efficacy of this maturation process in inactivating important pathogens that may be present in milk, such as Mycobacterium bovis and Brucella abortus. Thus, the objectives of this study were to produce parmesan-type cheese experimentally contaminated with M. bovis and B. abortus and evaluate the survival of these pathogens along 2-month maturation. Parmesan-type cheese was manufactured in the laboratory using whole pasteurized milk with or without inoculation with M. bovis (SB1033 or B. abortus (1119-3 and matured at 18°C for up to 63 days. M. bovis was inoculated in Stonebrink-Leslie medium supplemented with antibiotics and incubated at 37°C for 45 days, and B. abortus was incubated in Farrel medium at 36°C for 3 days. The average D18°C value, weighted by variance, was 37.5 ± 5.3 days for M. bovis and 5.9 ± 0.7 days for B. abortus. The average physicochemical parameters in the cheese at the end of the study were as follows: pH = 4.89, water activity = 0.976, and moisture percentage = 43.1%. The pH might have contributed to the reduction in the population of B. abortus but seems not to have influenced the population of M. bovis. We conclude that the duration of the maturation process influences the size of the surviving populations of M. bovis and B. abortus, and that the shortening of the maturation duration might not ensure a decline in pathogen levels to safe levels. Thus, complementary studies considering the effect of several other technological aspects on the survival of these pathogens are required, including the effect of the lactic acid bacterial population, salt content, and temperature of maturation.

  6. Carrageenan type effect on soybean oil/soy protein isolate emulsion employed as fat replacer in panela-type cheese

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    Rojas-Nery, E.

    2015-12-01

    Full Text Available In order to modify the fatty acid profile of panela-type cheese (a Mexican fresh cheese, emulsified soybean oil with soy protein isolate and different carrageenan (iota, kappa or lambda was employed as fat replacer. The replacement of milk fat in panela-type cheese resulted in higher cheese yield values and moisture content, besides a concomitant lower fat phase and higher protein content, due to a soy protein isolate in emulsified soybean oil. Fat replacement resulted in a harder but less cohesive, spring and resilient texture, where differences in texture could be attributed to the specific carrageenan-casein interactions within the rennet coagulated cheese matrix. The FTIR analysis showed that the milk fat replacement changed the fatty acid profile, also in function of the type of carrageenan employed. Lambda carrageenan containing emulsions improved moisture retention and maintained the textural properties of panela-type cheese.Para modificar el perfil de ácidos grasos de los quesos tipo panela (queso fresco popular en México, se utilizó aceite de soja emulsionado con aislado de proteína de soja y diferentes carrageninas (iota, kappa o lambda como sustituto de la grasa. Reemplazar la grasa de la leche en el queso tipo panela resultó en mayor rendimiento quesero y mayor contenido de humedad, además de una concomitante menor fase grasa y mayor contenido de proteína, debido al aislado de proteína de soja en el aceite de soja emulsionado. La sustitución de la grasa dio como resultado una textura más dura, pero menos cohesiva, elástica y resiliente, donde estas diferencias podrían ser atribuidas a la interacción especifica entre carrageninas-caseinas en la matriz coagulada del queso. El análisis de FTIR muestra que reemplazar la grasa de la leche cambia el perfil de ácidos grasos, también en función del tipo de carragenina empleado. Las emulsiones con lambda carrageninas mejoraron la retención de humedad y mantuvieron las

  7. The formation of fat-derived flavour compounds during the ripening of Gouda-type cheese

    NARCIS (Netherlands)

    Alewijn, M.

    2006-01-01

    Cheese flavour is an important quality attribute, and is mainly formed during cheese ripening. Besides compounds that are formed from protein and carbohydrates, milk fat-derived compounds are essential for cheese flavour. Before, but mainly during ripening, free fatty acids, lactones, ketones,

  8. Retrospective study on the hygienic quality of fresh ricotta cheeses produced in Sicily, Italy

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    Maria Luisa Scatassa

    2018-04-01

    Full Text Available The present work was carried out to investigate the microbiological profile of Sicilian ewes’ ricotta cheeses during fifteen years of investigations (2002-2016. The samples were collected between those conferred to the Istituto Zooprofilattico Sperimentale della Sicilia (IZSSi Adelmo Mirri, Palermo (Italy, by the competent authority during official control, by food business operator in HACCP systems and in research projects. Enterobacteriaceae, Escherichia coli and coagulase-positive staphylococci (CPS were found only in some samples. Bacillus cereus was detected in c.a. 16% of samples but the level of contaminations did not reach the threshold that leads to significant toxin production. Pathogenic bacteria such as Listeria monocytogenes, Salmonella spp. and Brucella spp. were never detected. Furthermore, a total of 47 of lactic acid bacteria (LAB strains were identified at species level by sequencing the 16S rRNA gene, resulting in the identification of 10 species belonging to four genera Enterococcus, Lactobacillus, Lactococcus and Leuconostoc, commonly employed as starter and non starter cultures in different traditional cheese. Results of this study highlighted an improvement of the hygienic conditions of the Sicilian ewes’ ricotta cheeses during the last ten years of investigation. This observation was confirmed from reduction of undesired microorganisms such as Enterobacteriaceae, E.coli and CPS, used to define the process hygiene criteria. However, in order to improve the final quality of this product are needed further strategy such as the dairy makers training, with the aim to apply a good hygienic practices during the production.

  9. CHARACTERIZATION OF AUTOCHTHONUS LACTIC FLORA OF A CAMPANIAN CHILLI CHEESE PRODUCED FROM RAW SHEEP MILK

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    A. Mormile

    2012-08-01

    Full Text Available The natural lactic flora of the artisanal chilli “Tramonti” cheese, a typical product manufactured in the “Lattari mountains”, area of Salerno province (Italy, was investigated. Particular attention was paid to the growth dynamics assessment and to the molecular identification of the indigenous lactic acid bacteria involved in the ripening of this cheese made with raw sheep milk without starter cultures. One batch was monitored taking 4 sample on 0, 30, 50 and 105 ripening days. Lactobacillus and Lactococcus were enumerated and randomly isolated on MRS and LM17 agar (32ºC x 48h -mesophilic flora- and 42°C x 48h -thermophilic flora, respectively. N. 66 presumptive lactic acid bacteria isolates, gram positive and catalase negative, were genotipically identified by Ribotyping. Mesophilic Lactobacillus remained at levels of 107 cfu/g during whole maturation time and thermophilic Lactobacillus, from initial values of 105 cfu/g, reached concentratios of 106 cfu/g at the end of maturation. Mesophilic and thermophilic Lactococcus showed, on average, levels of 106 since the beginning of the ripening. Ribotyping allowed to detect 4 lactic acid bacteria species: Enterococcus faecium (65,15%, Lactococcus lactis spp. cremoris (24,24%, Enterococcus faecalis (6,06% and Enterococcus durans (4,54%, showing the diversity of indigenous lactic acid bacteria of chilli “Tramonti” cheese.

  10. Diversity and dynamic of lactic acid bacteria strains during aging of a long ripened hard cheese produced from raw milk and undefined natural starter.

    Science.gov (United States)

    Pogačić, Tomislav; Mancini, Andrea; Santarelli, Marcela; Bottari, Benedetta; Lazzi, Camilla; Neviani, Erasmo; Gatti, Monica

    2013-12-01

    The aim of this study was to explore diversity and dynamic of indigenous LAB strains associated with a long ripened hard cheese produced from raw milk and undefined natural starter such as PDO Grana Padano cheese. Samples of milk, curd, natural whey culture and cheeses (2nd, 6th, 9th and 13th months of ripening) were collected from 6 cheese factories in northern Italy. DNA was extracted from each sample and from 194 LAB isolates. tRNA(Ala)-23S rDNA-RFLP was applied to identify isolates. Strain diversity was assessed by (GTG)5 rep-PCR and RAPD(P1)-PCR. Finally, culture-independent LH-PCR (V1-V2 16S-rDNA), was considered to explore structure and dynamic of the microbiota. Grana Padano LAB were represented mainly by Lactobacillus rhamnosus, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus delbrueckii, Lactobacillus helveticus and Pediococcus acidilactici, while the structure and dynamic of microbiota at different localities was specific. The strength of this work is to have focused the study on isolates coming from more than one cheese factories rather than a high number of isolates from one unique production. We provided a valuable insight into inter and intraspecies diversity of typical LAB strains during ripening of traditional PDO Grana Padano, contributing to the understanding of specific microbial ecosystem of this cheese. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Application of culture dependent and cultural-independent techniques to investigate the dynamics of microorganisms during industrial cheese making of a Gouda type cheese

    OpenAIRE

    Perolari, Alessandra

    2012-01-01

    The aim of this work was to study the microbial dynamic in a Gouda type cheese applying a comparison between culture-dependent technique, plate count, and culture-independent technique as PCR-DGGE. The study was also focus on the analyse of the efficiency of the pasteurizer, and its cleaning steps. The study was conducted analysing 4 batches for each of the two days of production, Monday and Friday. Between batch 16 and 17 there was a quick cleaning, and between batch 32 and batch 1, of th...

  12. Temperature and relative humidity influence the ripening descriptors of Camembert-type cheeses throughout ripening.

    Science.gov (United States)

    Leclercq-Perlat, M-N; Sicard, M; Perrot, N; Trelea, I C; Picque, D; Corrieu, G

    2015-02-01

    Ripening descriptors are the main factors that determine consumers' preferences of soft cheeses. Six descriptors were defined to represent the sensory changes in Camembert cheeses: Penicillium camemberti appearance, cheese odor and rind color, creamy underrind thickness and consistency, and core hardness. To evaluate the effects of the main process parameters on these descriptors, Camembert cheeses were ripened under different temperatures (8, 12, and 16°C) and relative humidity (RH; 88, 92, and 98%). The sensory descriptors were highly dependent on the temperature and RH used throughout ripening in a ripening chamber. All sensory descriptor changes could be explained by microorganism growth, pH, carbon substrate metabolism, and cheese moisture, as well as by microbial enzymatic activities. On d 40, at 8°C and 88% RH, all sensory descriptors scored the worst: the cheese was too dry, its odor and its color were similar to those of the unripe cheese, the underrind was driest, and the core was hardest. At 16°C and 98% RH, the odor was strongly ammonia and the color was dark brown, and the creamy underrind represented the entire thickness of the cheese but was completely runny, descriptors indicative of an over ripened cheese. Statistical analysis showed that the best ripening conditions to achieve an optimum balance between cheese sensory qualities and marketability were 13±1°C and 94±1% RH. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  13. Consumers’ attitude and opinion towards different types of fresh cheese: an exploratory study

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    Cássia Pereira de BARROS

    2016-01-01

    Full Text Available Abstract Fresh cheese stands out for its tradition and widespread consumption in Brazil. However, there is a lack of information on motivation towards the consumption of available fresh cheeses in the Brazilian market. Focus group sessions were used to explore consumers’ attitude and opinion about fresh cheese. Products with different characteristics were used to stimulate discussion among participants including cheese with “no added salt”, the claim “contains probiotic microorganisms” and products processed with goat milk. The salt content played an important role on the consumer intention to purchase of fresh cheese. Participants stated that they would consume cheese without salt only by following a medical prescription. However, the subjects declared that they would buy reduced salt cheese if such reduction would not compromise the flavor. The meaning of the claim “contains probiotic microorganisms” was often declared as unknown during the discussion. However, they would buy a probiotic product. In addition, it was mentioned that a premium price would be paid for such functional cheese. Participants declared that would buy goat cheese. Nevertheless, to pay a higher price over the conventional one was a controversial and debatable issue among consumers. Results revealed important implications for the development of marketing strategies for fresh cheese.

  14. Physical, chemical and texture characteristics of Aro cheese

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    González, M.L.

    2017-10-01

    Full Text Available In 2016, Mexico’s total annual production of cheese was 375,181 tons. Cheese is widely consumed among all socioeconomic groups, and the decision to purchase this product is based on income, with a wide variety of cheeses, brands, and styles available. The fresco cheese is the most popular type and is mostly produced according to traditional or artisanal methods in small family businesses, and small and medium-sized enterprises. It is made with the milk of the producers' livestock, giving it an added value. In Mexico, however, there is not enough scientific information related to the characterization of various dairy products of artisanal production, for example, Aro cheese. The aim of the present study was to define the physical, chemical, and rheological characteristics of the Aro cheese that is commercialized in Teotitlán de Flores Magón, Oaxaca, Mexico. Twenty-four samples of Aro cheese were collected in four establishments with high sales in Teotitlán de Flores Magón, Oaxaca, for analysis physical (Diameter, weight, height and color, chemical (pH, acidity, aw, chlorides, moisture, ashes, protein and fat, and texture (hardness, springiness, adhesiveness and cohesiveness. No difference was found in weight, diameter, height, and color (L* and b*. However, differences in hardness and cohesiveness were found. Although Aro cheese is characterized as an enzymatically coagulated cheese, pH values of 5.82 to 6.08 were recorded, and the data relating to moisture, protein, fat, and chlorides are similar to other Mexican fresh cheeses. The cheese of Aro that is commercialized in Teotitlán de Flores Magón, presents similar physical, chemical and texture characteristics to other fresh cheeses of artisanal production.

  15. BIOCHEMICAL CHARACTERISTICS OF LACTIC ACID PRODUCING BACTERIA AND PREPARATION OF CAMEL MILK CHEESE BY USING STARTER CULTURE

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    T. Ahmed and R. Kanwal

    2004-04-01

    Full Text Available Lactic acid bacteria (LAB were isolated from camel milk by culturing the milk on specific media and pure culture was obtained by sub-culturing. Purification of culture was confirmed by Gram’s staining and identified by different biochemical tests. Camel milk contained lactic acid producing bacteria like Streptococci such as S. cremoris and S. lactis and Lactobacilli such as L. acidophilus. L. acidophilus grew more rapidly in camel milk than others as its growth was supported by camel milk. Ability of each strain was tested to convert lactose of milk into lactic acid. It was observed that 66% lactose was converted by S. lactis 20, whereas S. cremoris 22 and L. acidophilus 23 converted 56 and 74% lactose into lactic acid, respectively. Effect of freeze-drying was also recorded and the results showed that in all cases there was a slight decrease in the cell count before and after the freeze-drying. The decrease was approximately 0.47, 0.078 and 0.86% for S. lactis 20, S. cremoris 22 and L. acidophilus 23, respectively. Starter culture was prepared from strains isolated from camel milk. Camel and buffalo milk cheese was prepared by using starter culture. The strains isolated from camel milk were best for acid production and coagulated the milk in less time. It is concluded that cheese can be prepared successfully from camel milk and better results can be obtained by coagulating milk with starter culture.

  16. Microbiological and biochemical aspects of Camembert-type cheeses depend on atmospheric composition in the ripening chamber.

    Science.gov (United States)

    Leclercq-Perlat, M-N; Picque, D; Riahi, H; Corrieu, G

    2006-08-01

    Camembert-type cheeses were prepared from pasteurized milk seeded with Kluyveromyces lactis, Geotrichum candidum, Penicillium camemberti, and Brevibacterium aurantiacum. Microorganism growth and biochemical dynamics were studied in relation to ripening chamber CO(2) atmospheric composition using 31 descriptors based on kinetic data. The chamber ripening was carried out under 5 different controlled atmospheres: continuously renewed atmosphere, periodically renewed atmosphere, no renewed atmosphere, and 2 for which CO(2) was either 2% or 6%. All microorganism dynamics depended on CO(2) level. Kluyveromyces lactis was not sensitive to CO(2) during its growth phases, but its death did depend on it. An increase of CO(2) led to a significant improvement in G. candidum. Penicillium camemberti mycelium development was enhanced by 2% CO(2). The equilibrium between P. camemberti and G. candidum populations was disrupted in favor of the yeast when CO(2) was higher than 4%. Growth of B. aurantiacum depended more on O(2) than on CO(2). Two ripening progressions were observed in relation to the presence of CO(2) at the beginning of ripening: in the presence of CO(2), the ripening was fast-slow, and in the absence of CO(2), it was slow-fast. The underrind was too runny if CO(2) was equal to or higher than 6%. The nitrogen substrate progressions were slightly related to ripening chamber CO(2) and O(2) levels. During chamber ripening, the best atmospheric condition to produce an optimum between microorganism growth, biochemical dynamics, and cheese appearance was a constant CO(2) level close to 2%.

  17. Maltaricin CPN, a new class IIa bacteriocin produced by Carnobacterium maltaromaticum CPN isolated from mould-ripened cheese.

    Science.gov (United States)

    Hammi, I; Delalande, F; Belkhou, R; Marchioni, E; Cianferani, S; Ennahar, S

    2016-11-01

    The purpose of this study was to isolate, characterize and determine the structure and the antibacterial activities of a bacteriocin produced by Carnobacterium maltaromaticum CPN, a strain isolated from unpasteurized milk Camembert cheese. This bacteriocin, termed maltaricin CPN, was produced at higher amounts in MRS broth at temperatures between 15°C and 25°C. It was purified to homogeneity from culture supernatant by using a simple method consisting of cation-exchange and reversed-phase chromatographies. Mass spectrometry showed that maltaricin was a 4427·29 Da bacteriocin. Its amino acid sequence was determined by Edman degradation which showed that it had close similarity with bacteriocins of the class IIa. Maltaricin CPN consisted in fact of 44 unmodified amino acids including two cysteine residues at positions 9 and 14 linked by a disulphide bond. The antimicrobial activity of maltaricin CPN covered a range of bacteria, with strong activity against many species of Gram-positive bacteria, especially the food-borne pathogen Listeria monocytogenes, but no activity against Gram-negative ones. In the studied conditions, C. maltaromaticum CPN produced a new class IIa bacteriocin with strong anti-Listeria activity. The study covers the purification and the structural characterization of a new bacteriocin produced by strain C. maltaromaticum CPN isolated from Camembert cheese. Its activity against strains of L. monocytogenes and higher production rates at relatively low temperatures show potential technological applications to improve the safety of refrigerated food. © 2016 The Society for Applied Microbiology.

  18. Microstructure of industrially produced reduced and low fat Turkish white cheese as influenced by the homogenization of cream

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    Karaman, A. D.

    2012-09-01

    Full Text Available The microstructure and fat globule distribution of reduced and low fat Turkish white cheese were evaluated. Reduced and low fat cheeses were manufactured from 1.5% and 0.75% fat milk respectively which were standardized unhomogenized and homogenized cream in a dairy plant. Homogenized and non-homogenized creams and cheese whey were analyzed for fat globule distribution and cheese samples were also analyzed for microstructure characteristics. According to the results, the homogenization of cream decreased the size of fat globules; and showed that a large number of fat particles were dispersed in the in matrix and improved the lubrication of cheese microstructure. According to the micrographs for the fat, which was not removed, they exhibited a more extended matrix with a few small fat globules compared to the defatted micrographs. Homogenization of cream produces small fat globules and unclustured fat globules were found in the resulting whey. These results are important for dairy processors for using cream homogenization as a processing tool at the industrial level.

    Se estudia la microestructura y distribución de los glóbulos de grasa de quesos blancos turcos bajos en grasa. Quesos con reducida y baja cantidad en grasa fueron fabricados conteniendo entre el 1,5% y 0,75% de grasa de leche, respectivamente, y con cremas homogeneizadas y no homogeneizadas, en una planta de lácteos. Las cremas homogeneizadas y no homogeneizadas y el suero de los quesos se analizaron para determinar la distribución de los glóbulos de grasa y también se analizaron las características de la microestructura de muestras de queso. De acuerdo con los resultados, la homogeneización de la crema reduce el tamaño de los glóbulos de grasa, mostrando un gran número de partículas de grasa dispersa en la matriz de caseína que mejoró la lubricación de la microestructura del queso. De acuerdo con las micrografías de la grasa que no se elimina, estas exhiben

  19. Growth inhibition of Listeria spp. on Camembert cheese by bacteria producing inhibitory substances.

    Science.gov (United States)

    Sulzer, G; Busse, M

    1991-12-01

    Bacterial strains exhibiting antimicrobial activity towards other bacteria are quite common in nature. During the past few years several genera have been shown to exert inhibitory action against Listeria. spp. In the present work strains of Enterococcus, Lactobacillus and Lactococcus were tested for their influence on the development of Listeria spp. on Camembert cheese. Partial or complete inhibition of growth of Listeria spp. was observed using various inhibitory bacteria. Complete inhibition occurred when the inhibitory strain was used as a starter culture and there was a low level of contamination with Listeria spp. during the first stage of ripening. Very little inhibition occurred if the inhibitory strain was added together with the starter culture.

  20. Ability of 3 tanniferous forage legumes to modify quality of milk and Gruyère-type cheese.

    Science.gov (United States)

    Girard, M; Dohme-Meier, F; Wechsler, D; Goy, D; Kreuzer, M; Bee, G

    2016-01-01

    Condensed tannins (CT) may affect ruminal biohydrogenation of dietary polyunsaturated fatty acids. A feeding experiment was conducted with 24 Holstein cows to evaluate whether diets containing CT from different forage legumes can increase polyunsaturated fatty acids, especially n-3 fatty acid content in milk and cheese, without affecting negatively their physicochemical and sensorial properties. Cows were assigned to 4 treatment groups (n=6) for 52 d, divided into 2 periods: a control period (CoP) and an experimental period (ExP). During the CoP, cows received a basal diet composed of hay, corn silage, ExtruLin (Trinova Handel & Marketing AG, Wangen, Switzerland), concentrate, and alfalfa (AF) in a ratio of 45:25:5:7:18. In the ExP, in 3 of the 4 groups AF was replaced by either sainfoin (SF; 19% CT in dry matter) or 1 of 2 cultivars of birdsfoot trefoil [Polom (BP), 3% CT; Bull (BB), 5% CT]. At the end of each period, milk was collected on 3 consecutive days and analyzed for milk gross composition and fatty acid profile and was processed to Gruyère-type cheese. A trained panel assessed the sensory quality of raw milk and cheese using discriminative and descriptive tests. This experimental design consisting of AF in both the CoP and ExP allowed us to quantify effects due to lactation stage and experimental diets. In both the CoP and ExP, dry matter intake and milk yield did not differ among treatment groups. From the CoP to the ExP, milk urea content was reduced by 23% with SF, remained unchanged with BP, and tended to increase with AF and BB. The odor of the raw BB milk was judged to be different from AF milk. With SF, switching from the CoP to the ExP resulted in a 17% increase of the 18:3n-3 proportion in milk and cheese lipids. In BP cheese, the increase was 3%, whereas it tended to decrease in BB cheese. Additionally, the 20:5n-3 and 22:5n-3 proportions tended to increase in SF cheese from the CoP to the ExP. Compared with the AF cheeses, cheeses from cows

  1. COTTAGE CHEESE PRODUCTS FUNCTIONALITY

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    L. V. Golubeva

    2015-01-01

    Full Text Available Cottage cheese products holds a significant place among the dairy and milk-containing products. The range of products includes cheese: cheese, pastes, creams, cakes, etc. Such diversity can be attributed to their popularity among the population and benefit brought by the body from regular use. Curd protein is much better and easier to digest by the body than protein fish, meat or milk. Rich curd products lysine and methionine. Minerals contained in cheese products have a positive effect on bone formation and structure of tissues. The composition of curd products, in addition to cheese and dairy ingredients may include non-dairy ingredients origin. Today, for the production of cheese products use the most advanced technologies to further enrich its structure and significantly improve the nutritional value. Pine nut is widely used in the manufacture of many dairy products. But, in most cases, the production of dairy products as a filler used pine nut cake, which deprives the finished product valuable cedar oil. The authors proposed a technology for producing curd product with the addition of pine nuts and honey (pine nuts and fructose. Compatible with cream cheese filling insertion determined sensory organoleptic point scale. he optimum dosage of components: pine nuts – 5 %, honey – 10 % fructose – 7 %. Technological process of cottage cheese product is different from the traditional operations training components and their introduction into the finished cheese. Identify indicators of quality of the new product. Production of curd products thus expanding the range of dairy products functional orientation.

  2. Effect of lupine as cheese base substitution on technological and nutritional properties of processed cheese analogue.

    Science.gov (United States)

    Awad, Rezik Azab; Salama, Wafaa Mohammed; Farahat, Azza Mahmoud

    2014-01-01

    Healthy foods have been met with marked success in the last two decades. Lupine flours, protein concentrates, and isolates can be applied as a substance for enriching different kinds of food systems such as bakery products, lupine pasta, ice cream, milk substitutes. Imitation processed cheese is made from mixtures of dairy and/or non dairy proteins and fat/oils and is variously labeled analogue, artificial, extruded, synthetic and/or filled. Processed cheese can be formulated using different types of cheese with different degree of maturation, flavorings, emulsifying, salts, and/or several ingredients of non-dairy components. Non-dairy ingredients have been used in processed cheese for many dietary and economic reasons. In this study, lupine paste was used to substitute 25, 50, 75 and 100% of cheese in base formula of processed cheese analogue (PCA). Matured Ras cheese (3 months old) was manufactured using fresh cow milk. Soft cheese curd was manufactured using fresh buffalo skim milk. Emulsifying salts S9s and Unsalted butter were used. Lupine termis paste was prepared by soaking the seeds in tap water for week with changing the water daily, and then boiled in water for 2 hrs, cooled and peeled. The peeled seeds were minced, blended to get very fine paste and kept frozen until used. Lupine paste was used to substitute 25, 50, 75 and 100% of cheese in base formula of processed cheese analogue (PCA). The obtained PCA were analysed when fresh and during storage up to 3 months at 5±2°C for chemical composition, physical and sensory properties. The histopathological effect of lupines on alloxan diabetic albino rats and nutritional parameters were also investigated. Incorporation of lupine paste in PCA increased the ash and protein contents while meltability and penetration values of resultant products were decreased. Adding lupine in PSA formula had relatively increased the oil index and firmness of products. Feeding rats a balanced diet containing processed cheese

  3. Determination of endogenous concentrations of nitrites and nitrates in different types of cheese in the United States: method development and validation using ion chromatography.

    Science.gov (United States)

    Genualdi, Susan; Jeong, Nahyun; DeJager, Lowri

    2018-04-01

    Nitrites and nitrates can be present in dairy products from both endogenous and exogenous sources. In the European Union (EU), 150 mg kg - 1 of nitrates are allowed to be added to the cheese milk during the manufacturing process. The CODEX General Standard for Food Additives has a maximum permitted level of 50 mg kg - 1 residue in cheese, while in the United States (U.S.) nitrates are unapproved for use as food additives in cheese. In order to be able to investigate imported cheeses for nitrates intentionally added as preservatives and the endogenous concentrations of nitrates and nitrites present in cheeses in the U.S. marketplace, a method was developed and validated using ion chromatography with conductivity detection. A market sampling of cheese samples purchased in the Washington DC metro area was performed. In 64 samples of cheese, concentrations ranged from below the method detection limit (MDL) to 26 mg kg - 1 for nitrates and no concentrations of nitrites were found in any of the cheese samples above the MDL of 0.1 mg kg - 1 . A majority of the samples (93%) had concentrations below 10 mg kg - 1 , which indicate the presence of endogenous nitrates. The samples with concentrations above 10 mg kg - 1 were mainly processed cheese spread, which can contain additional ingredients often of plant-based origin. These ingredients are likely the cause of the elevated nitrate concentrations. The analysis of 12 additional cheese samples that are liable to the intentional addition of nitrates, 9 of which were imported, indicated that in this limited study, concentrations of nitrate in the U.S.-produced cheeses did not differ from those in imported samples.

  4. Enterocin 96, a novel class II bacteriocin produced by Enterococcus faecalis WHE 96, isolated from Munster cheese.

    Science.gov (United States)

    Izquierdo, Esther; Wagner, Camille; Marchioni, Eric; Aoude-Werner, Dalal; Ennahar, Saïd

    2009-07-01

    Enterococcus faecalis WHE 96, a strain isolated from soft cheese based on its anti-Listeria activity, produced a 5,494-Da bacteriocin that was purified to homogeneity by ultrafiltration and cation-exchange and reversed-phase chromatographies. The amino acid sequence of this bacteriocin, named enterocin 96, was determined by Edman degradation, and its structural gene was sequenced, revealing a double-glycine leader peptide. After a comparison with other bacteriocins, it was shown that enterocin 96 was a new class II bacteriocin that showed very little similarity with known structures. Enterocin 96 was indeed a new bacteriocin belonging to class II bacteriocins. The activity spectrum of enterocin 96 covered a wide range of bacteria, with strong activity against most gram-positive strains but very little or no activity against gram-negative strains.

  5. Growth and Survival of Acid-Resistant and Non-Acid-Resistant Shiga-Toxin-Producing Escherichia coli Strains during the Manufacture and Ripening of Camembert Cheese.

    Science.gov (United States)

    Montet, M P; Jamet, E; Ganet, S; Dizin, M; Miszczycha, S; Dunière, L; Thevenot, D; Vernozy-Rozand, C

    2009-01-01

    Growth and survival of acid-resistant (AR) and non-acid-resistant (NAR) Shiga-toxin-producing Escherichia coli (STEC) strains were investigated during the manufacture and ripening of microfiltered milk Camembert cheeses. The induction of acid resistance of the STEC strains in cheeses was also studied. Six different mixtures of AR and/or NAR STEC strains were inoculated separately into microfiltered milk at a level of 10(3) CFU mL(-1). The STEC counts (AR and NAR) initially increased by 1 to 2 log(10) CFU g(-1) during cheese-making. Thereafter, the populations stabilized during salting/drying and then decreased during the early stages of ripening. Exposing the STEC strains in artificially inoculated cheeses to simulated gastric fluid (SGF - pH: 2.0) reduced the number of NAR strains to undetectable levels within 40 minutes, versus 120 minutes for the AR STEC strains. AR and NAR STEC were able to survive during the manufacture and ripening of Camembert cheese prepared from microfiltered milk with no evidence of induced acid tolerance in NAR STEC strains.

  6. Growth and Survival of Acid-Resistant and Non-Acid-Resistant Shiga-Toxin-Producing Escherichia coli Strains during the Manufacture and Ripening of Camembert Cheese

    Directory of Open Access Journals (Sweden)

    M. P. Montet

    2009-01-01

    Full Text Available Growth and survival of acid-resistant (AR and non-acid-resistant (NAR Shiga-toxin-producing Escherichia coli (STEC strains were investigated during the manufacture and ripening of microfiltered milk Camembert cheeses. The induction of acid resistance of the STEC strains in cheeses was also studied. Six different mixtures of AR and/or NAR STEC strains were inoculated separately into microfiltered milk at a level of 103 CFU mL−1. The STEC counts (AR and NAR initially increased by 1 to 2 log⁡10 CFU g−1 during cheese-making. Thereafter, the populations stabilized during salting/drying and then decreased during the early stages of ripening. Exposing the STEC strains in artificially inoculated cheeses to simulated gastric fluid (SGF - pH: 2.0 reduced the number of NAR strains to undetectable levels within 40 minutes, versus 120 minutes for the AR STEC strains. AR and NAR STEC were able to survive during the manufacture and ripening of Camembert cheese prepared from microfiltered milk with no evidence of induced acid tolerance in NAR STEC strains.

  7. Physical characterization and sanitary conditions of cheese type cabacinha market places in three municipalities of the Jequitinhonha Valley, MG, Brazil

    Directory of Open Access Journals (Sweden)

    Adair da Silva Santos Filho

    2017-09-01

    Full Text Available Cheese type cabacinha from Vale do Jequitinhonha is obtained by curd heating in a similar process made to Mozzarella, but the raw milk is unpasteurized and the final product is stored unpackaged and at room temperature. This milk derivative may contribute to the increase the income of the local population, especially the residents of the edges of roads, due to the flow of vehicles and possible buyers. The purpose of this work was to identify the physical and sanitary conditions of cheese type cabacinha market places present in three municipalities of the Vale do Jequitinhonha, MG, Brazil. Previously the investigation was detected the number of marketplaces that sell these cheese in the Medina, Cachoeira de Pajeú and Pedra Azul, municipalities of the state of Minas Gerais, Brazil, located on the surrounding area of the highways BR 251 and BR 116. Afterward as developed a physical and sanitary checklist and it were filled in loco. It was observed that most market places were not provided of masonry walls, piped water or toilet and sink. It is also common to the presence of possible contamination vectors in surroundings, such as dogs and insects. It is verified that most of these cheese is exposed in pairs held by string and unpackaged. This study demonstrated the precariousness of the physical structures and consequently the lack of adequate sanitary conditions in the cheese type cabacinha market places. Because it is an artisanal product from family farming, which generates income and employment in the field deserve more attention of competent state and municipal authorities.

  8. The Microbiology of Traditional Hard and Semihard Cooked Mountain Cheeses.

    Science.gov (United States)

    Beuvier, Eric; Duboz, Gabriel

    2013-10-01

    Traditional cheeses originate from complex systems that confer on them specific sensory characteristics. These characteristics are linked to various factors of biodiversity such as animal feed, the use of raw milk and its indigenous microflora, the cheese technology, and the ripening conditions, all in conjunction with the knowledge of the cheesemaker and affineur. In Europe, particularly in France, the preservation of traditional cheesemaking processes, some of which have protected designation of origin, is vital for the farming and food industry in certain regions. Among these cheeses, some are made in the Alps or Jura Mountains, including Comté, Beaufort, Abondance, and Emmental, which are made from raw milk. The principle of hard or semihard cooked cheese, produced in the Alps and Jura Mountains, was to make a product during the summer-a period during which the animals feed more and milk production is high-with a shelf life of several months that could be consumed in winter. Today, these traditional cheeses are produced according to a specific approach combining science and tradition in order to better understand and preserve the elements that contribute to the distinctiveness of these cheeses. To address this complex problem, a global approach to the role of the raw milk microflora in the final quality of cheeses was initially chosen. The modifications resulting from the elimination of the raw milk microflora, either by pasteurization or by microfiltration, to the biochemistry of the ripening process and ultimately the sensory quality of the cheeses were evaluated. This approach was achieved mainly with experimental hard cooked cheeses. Other types of traditional cheese made with raw and pasteurized milk are also considered when necessary. Besides the native raw milk microflora, traditional lactic starters (natural or wild starters) also participate in the development of the characteristics of traditional hard and semihard cooked mountain cheeses. After an

  9. Effects of atmospheric composition on respiratory behavior, weight loss, and appearance of Camembert-type cheeses during chamber ripening.

    Science.gov (United States)

    Picque, D; Leclercq-Perlat, M-N; Corrieu, G

    2006-08-01

    Respiratory activity, weight loss, and appearance of Camembert-type cheeses were studied during chamber ripening in relation to atmospheric composition. Cheese ripening was carried out in chambers under continuously renewed, periodically renewed, or nonrenewed gaseous atmospheres or under a CO(2) concentration kept constant at either 2 or 6% throughout the chamber-ripening process. It was found that overall atmospheric composition, and especially CO(2) concentration, of the ripening chamber affected respiratory activity. When CO(2) was maintained at either 2 or 6%, O(2) consumption and CO(2) production (and their kinetics) were higher compared with ripening trials carried out without regulating CO(2) concentration over time. Global weight loss was maximal under continuously renewed atmospheric conditions. In this case, the airflow increased exchanges between cheeses and the atmosphere. The ratio between water evaporation and CO(2) release also depended on atmospheric composition, especially CO(2) concentration. The thickening of the creamy underrind increased more quickly when CO(2) was present in the chamber from the beginning of the ripening process. However, CO(2) concentrations higher than 2% negatively influenced the appearance of the cheeses.

  10. Comparison of performance and quantitative descriptive analysis sensory profiling and its relationship to consumer liking between the artisanal cheese producers panel and the descriptive trained panel.

    Science.gov (United States)

    Ramírez-Rivera, Emmanuel de Jesús; Díaz-Rivera, Pablo; Guadalupe Ramón-Canul, Lorena; Juárez-Barrientos, José Manuel; Rodríguez-Miranda, Jesús; Herman-Lara, Erasmo; Prinyawiwatkul, Witoon; Herrera-Corredor, José Andrés

    2018-04-25

    The aim of this research was to compare the performance and sensory profiling of a panel of artisanal cheese producers against a trained panel and their relationship to consumer liking (external preference mapping). Performance was analyzed statistically at an individual level using the Fisher's test (F) for discrimination, the mean square error for repeatability, and Manhattan plots for visualizing the intra-panel homogeneity. At group level, performance was evaluated using ANOVA. External preference mapping technique was applied to determine the efficiency of each sensory profile. Results showed that the producers panel was discriminant and repetitive with a performance similar to that of the trained panel. Manhattan plots showed that the performance of artisanal cheese producers was more homogeneous than trained panelists. The correlation between sensory profiles (Rv = 0.95) demonstrated similarities in the generation and use of sensory profiles. The external preference maps generated individually with the profiles of each panel were also similar. Recruiting individuals familiar with the production of artisanal cheeses as panelists is a viable strategy for sensory characterization of artisanal cheeses within their context of origin because their results were similar to those from the trained panel and can be correlated with consumer liking data. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  11. An application in cheddar cheese manufacture for a strain of Lactococcus lactis producing a novel broad-spectrum bacteriocin, lacticin 3147.

    Science.gov (United States)

    Ryan, M P; Rea, M C; Hill, C; Ross, R P

    1996-01-01

    Lactococcus lactis DPC3147, a strain isolated from an Irish kefir grain, produces a bacteriocin with a broad spectrum of inhibition. The bacteriocin produced is heat stable, particularly at a low pH, and inhibits nisin-producing (Nip+) lactococci. On the basis of the observation that the nisin structural gene (nisA) does not hybridize to DPC3147 genomic DNA, the bacteriocin produced was considered novel and designated lacticin 3147. The genetic determinants which encode lacticin 3147 are contained on a 63-kb plasmid, which was conjugally mobilized to a commercial cheese starter, L. lactis subsp. cremoris DPC4268. The resultant transconjugant, DPC4275, both produces and is immune to lacticin 3147. The ability of lacticin 3147-producing lactococci to perform as cheddar cheese starters was subsequently investigated in cheesemaking trials. Bacteriocin-producing starters (which included the transconjugant strain DPC4275) produced acid at rates similar to those of commercial strains. The level of lacticin 3147 produced in cheese remained constant over 6 months of ripening and correlated with a significant reduction in the levels of nonstarter lactic acid bacteria. Such results suggest that these starters provide a means of controlling developing microflora in ripened fermented products. PMID:8593062

  12. The Effects of the Types of Milk (Cow, Goat, Soya and Enzymes (Rennet, Papain, Bromelain Toward Cheddar Cheese Production

    Directory of Open Access Journals (Sweden)

    Ariestya Arlene

    2015-04-01

    Full Text Available The objectives of this research are to study the effects of different types of milk and enzymes toward the yield and quality (moisture, ash, protein, fat content, and texture of cheddar cheese and the interaction between those two variables during the process. The types of milk are cow, goat, and soya milk, while the types of enzymes are rennet, papain, and bromelain enzymes. Regarding the procedure, the milk is first pasteurized before CaCl2 and Lactobacillus lactis that acts as the acidifier starter as much as 0.2% (w/v and 0.5% of the milk volume are added respectively. The amount of enzyme added is appropriate for the determination of enzyme dose. The curd is separated from the whey and then 2.5 grams of salt is added to 100 grams of curd. Afterwards, the curd is pressed until the water content decreases (cheese, then ripened for 1 month. The analyses conducted are moisture, ash, protein, fat content, and texture (hardness. The conclusion is the goat milk and the rennet enzyme are the suitable raw material for cheddar cheese production. Furthermore, different types of milk and enzymes affect the yield. However, there is no interaction between the types of milk and enzymes to the yield.

  13. In vitro evaluation of bacteriocin-like inhibitory substances produced by lactic acid bacteria isolated during traditional Sicilian cheese making

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    Giusi Macaluso

    2016-02-01

    Full Text Available Bacteriocins are antimicrobial proteins produced by bacteria that inhibit the growth of other bacteria with a bactericidal or bacteriostatic mode of action. Many lactic acid bacteria (LAB produce a high diversity of different bacteriocins. Bacteriocinogenic LAB are generally recognised as safe (GRAS and useful to control the frequent development of pathogens and spoilage microorganisms. For this reason they are commonly used as starter cultures in food fermentations. In this study, the authors describe the results of a screening on 699 LAB isolated from wooden vat surfaces, raw milk and traditional Sicilian cheeses, for the production of bacteriocin-like inhibitory substances, by comparing two alternative methods. The antagonistic activity of LAB and its proteinaceous nature were evaluated using the spot-on-the-lawn and the well-diffusion assay (WDA and the sensitivity to proteolytic (proteinase K, protease B and trypsin, amylolytic (α-amylase and lipolytic (lipase enzymes. The indicator strains used were: Listeria monocytogenes, Staphylococcus aureus, Escherichia coli, Salmonella enteritidis. A total of 223 strains (belonging to the species Enterococcus spp., Lactobacillus spp., Pediococcus spp., Streptococcus spp., Leuconostoc spp. and Lactococcus lactis were found to inhibit the growth of Listeria monocytogenes by using the spot-on-the-lawn method; only 37 of these were confirmed by using the WDA. The direct addition of bacteriocin-producing cultures into dairy products can be a more practical and economic option for the improvement of the safety and quality of the final product.

  14. Enterotoxin Producing Ability And Antimicrobial Susceptibility Of Coagulase-Negative Staphylococci Isolated From Goat Milk Cheese And Salted Yoghurt In Turkey

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    S. Pehlivanlar Onen

    2017-10-01

    Full Text Available The aim of this study was to determine enterotoxin producing ability and antimicrobial susceptibility of coagulase negative staphylococci CNS in goats bulk milk cheese and salted yoghurt. CNS strains were identified by using GP card in VITEK 2 system. The presence of enterotoxins was determined by enzyme immunoassay test by using RIDASCREEN test kit. Antibiotic susceptibility in CNS strains was detected by using AST-P640 card in VITEK 2 system. A total of 100 CNS strains were isolated in 22 55 bulk milk samples and in 23 57.5 cheese samples. Staphylococcus spp. could not be isolated from salted yoghurt samples. The most encountered species were S. caprae 51.9 S. chromogenes 11.5 and S. xylosus 9.6 from milk samples and S. saprophyticus 60.4 S. xylosus 12.5 and S. haemolyticus 8.3 from cheese samples. Four CNS strains 4 isolated from samples were capable of producing enterotoxin. While all isolates were resistant to at least one antibiotic 74 of CNS strains showed resistance to two or more antibiotics. Enterotoxin production ability and high antibiotic resistance of the CNS strains isolated from goat bulk milk and cheese can lead to a risk for public health.

  15. Temperature and relative humidity influence the microbial and physicochemical characteristics of Camembert-type cheese ripening.

    Science.gov (United States)

    Leclercq-Perlat, M-N; Sicard, M; Trelea, I C; Picque, D; Corrieu, G

    2012-08-01

    To evaluate the effects of temperature and relative humidity (RH) on microbial and biochemical ripening kinetics, Camembert-type cheeses were prepared from pasteurized milk seeded with Kluyveromyces marxianus, Geotrichum candidum, Penicillium camemberti, and Brevibacterium aurantiacum. Microorganism growth and biochemical changes were studied under different ripening temperatures (8, 12, and 16°C) and RH (88, 92, and 98%). The central point runs (12°C, 92% RH) were both reproducible and repeatable, and for each microbial and biochemical parameter, 2 kinetic descriptors were defined. Temperature had significant effects on the growth of both K. marxianus and G. candidum, whereas RH did not affect it. Regardless of the temperature, at 98% RH the specific growth rate of P. camemberti spores was significantly higher [between 2 (8°C) and 106 times (16°C) higher]. However, at 16°C, the appearance of the rind was no longer suitable because mycelia were damaged. Brevibacterium aurantiacum growth depended on both temperature and RH. At 8°C under 88% RH, its growth was restricted (1.3 × 10(7) cfu/g), whereas at 16°C and 98% RH, its growth was favored, reaching 7.9 × 10(9) cfu/g, but the rind had a dark brown color after d 20. Temperature had a significant effect on carbon substrate consumption rates in the core as well as in the rind. In the rind, when temperature was 16°C rather than 8°C, the lactate consumption rate was approximately 2.9 times higher under 88% RH. Whatever the RH, temperature significantly affected the increase in rind pH (from 4.6 to 7.7 ± 0.2). At 8°C, an increase in rind pH was observed between d 6 and 9, whereas at 16°C, it was between d 2 and 3. Temperature and RH affected the increasing rate of the underrind thickness: at 16°C, half of the cheese thickness appeared ripened on d 14 (wrapping day). However, at 98% RH, the underrind was runny. In conclusion, some descriptors, such as yeast growth and the pH in the rind, depended solely on

  16. Characterization and Application of Autochthonous Starter Cultures for Fresh Cheese Production

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    Andreja Leboš Pavunc

    2012-01-01

    Full Text Available The use of commercial starter cultures in fresh cheese production from pasteurized milk results in the loss of typical characteristics of artisan fresh cheese due to the replacement of complex native microbiota with a defined starter culture. Hence, the aim of this research is to isolate and characterize dominant lactic acid bacteria (LAB in artisan fresh cheese and to evaluate their capacity as autochthonous starter cultures for fresh cheese production. Fifteen most prevalent Gram-positive, catalase-negative and asporogenous bacterial strains were selected for a more detailed characterization. Eleven lactic acid bacterial strains were determined to be homofermentative cocci and four heterofermentative lactobacilli. Further phenotypic and genotypic analyses revealed that those were two different LAB strains with high acidifying and proteolytic activity, identified as Lactobacillus fermentum A8 and Enterococcus faecium A7. These two autochthonous strains, alone or in combination with commercial starter, were used to produce different types of fresh cheese, which were evaluated by a panel. Conventional culturing, isolation, identification and PCR-denaturing gradient gel electrophoresis (PCR-DGGE procedures, applied to the total fresh cheese DNA extracts, were employed to define and monitor the viability of the introduced LAB strains and their effect on the final product characteristics. Production of fresh cheese using a combination of commercial starter culture and selected autochthonous strains resulted in improved sensorial properties, which were more similar to the ones of spontaneously fermented fresh cheese than to those of cheese produced with only starter culture or selected strains. After 10 days of storage, that cheese retained the best sensorial properties in comparison with all other types of cheese. The presence of inoculated autochthonous and starter cultures and their identification was demonstrated by DGGE analysis. The obtained

  17. Growth and enterotoxin production of Staphylococcus aureus during the manufacture and ripening of Camembert-type cheeses from raw goats' milk.

    Science.gov (United States)

    Meyrand, A; Boutrand-Loei, S; Ray-Gueniot, S; Mazuy, C; Gaspard, C E; Jaubert, G; Perrin, G; Lapeyre, C; Vernozy-Rozand, C

    1998-09-01

    Tests were carried out to determine the effect of manufacturing procedures for a Camembert-type cheese from raw goats' milk on the growth and survival of Staphylococcus aureus organisms added to milk at the start of the process, and to study the possible presence of staphylococcal enterotoxin A in these cheeses. The initial staphylococcal counts were, respectively, 2, 3, 4, 5 and 6 log cfu ml-1. Cheese was prepared following the industrial specifications and ripened for 41 d. Detection of enterotoxins was done by the Vidas SET test and by an indirect double-sandwich ELISA technique using antienterotoxin monoclonal antibodies. Generally, numbers of microbes increased at a similar rate during manufacture in all cheeses until salting. During the ripening period, the aerobic plate count population and Staph. aureus levels remained stable and high. There was an approximately 1 log reduction of Staph. aureus in cheeses made with an initial inoculum of Staph. aureus greater than 10(3) cfu ml-1 at the end of the ripening period (41 d) compared with the count at 22 h. The level of staphylococcal enterotoxin A recovered varied from 1 to 3.2 ng g-1 of cheese made with an initial population of 10(3)-10(6) cfu ml-1. No trace of enterotoxin A was detected in cheeses made with the lowest Staph. aureus inoculum used in this study.

  18. Cheddar cheese ripening affects plasma nonesterified fatty acids and serum insulin concentrations in growing pigs

    DEFF Research Database (Denmark)

    Thorning, Tanja Kongerslev; Bendsen, Nathalie Tommerup; Jensen, Søren Krogh

    2015-01-01

    BACKGROUND: Meta-analyses of observational studies found cheese consumption to be inversely associated with risk of type 2 diabetes and metabolic syndrome. This may be attributed to the bioactive compounds produced during cheese ripening. OBJECTIVE: The objective of this study was to investigate ...

  19. Description of two Enterococcus strains isolated from traditional Peruvian artisanal-produced cheeses with a bacteriocin-like inhibitory activity

    Directory of Open Access Journals (Sweden)

    Aguilar Galvez A.

    2009-01-01

    Full Text Available The aim of this work was to isolate and to characterize strains of lactic acid bacteria (LAB with bacteriocin-like inhibitory activity from 27 traditional cheeses artisanal-produced obtained from different Peruvian regions. Twenty Gram+ and catalasenegative strains among 2,277 isolates exhibited bacteriocin-like inhibitory activity against Listeria monocytogenes CWBIB2232 as target strain. No change in inhibitory activity was observed after organic acid neutralization and treatment with catalase of the cell-free supernatant (CFS. The proteinic nature of the antimicrobial activity was confirmed for the twenty LAB strains by proteolytic digestion of the CFS. Two strains, CWBI-B1431 and CWBI-B1430, with the best antimicrobial activity were selected for further researches. These strains were taxonomically identified by phenotypic and genotypic analyses as Enterococcus mundtii (CWBI-B1431 and Enterococcus faecium (CWBI-B1430. The two strains were sensitive to vancomycin (MIC 2 μg.ml-1 and showed absence of haemolysis.

  20. A novel enterocin T1 with anti-Pseudomonas activity produced by Enterococcus faecium T1 from Chinese Tibet cheese.

    Science.gov (United States)

    Liu, Hui; Zhang, Lanwei; Yi, Huaxi; Han, Xue; Gao, Wei; Chi, Chunliang; Song, Wei; Li, Haiying; Liu, Chunguang

    2016-02-01

    An enterocin-producing Enterococcus faecium T1 was isolated from Chinese Tibet cheese. The enterocin was purified by SP-Sepharose and reversed phase HPLC. It was identified as unique from other reported bacteriocins based on molecular weight (4629 Da) and amino acid compositions; therefore it was subsequently named enterocin T1. Enterocin T1 was stable at 80-100 °C and over a wide pH range, pH 3.0-10.0. Protease sensitivity was observed to trypsin, pepsin, papain, proteinase K, and pronase E. Importantly, enterocin T1 was observed to inhibit the growth of numerous Gram-negative and Gram-positive bacteria including Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhimurium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Listeria monocytogenes. Take together, these results suggest that enterocin T1 is a novel bacteriocin with the potential to be used as a bio-preservative to control Pseudomonas spp. in food.

  1. The changes of flavour and aroma active compounds content during production of Edam cheese

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    Eva Vítová

    2011-01-01

    Full Text Available This work deals with the problem of flavour of Edam cheeses, i.e. natural hard cheese with low heat curd. The cheese samples were produced in dairy MILTRA B, Ltd., Městečko Trnávka.A number of volatile substances contribute to flavour of cheese including alcohols, aldehydes, ketones, fatty acids, esters, lactones, terpenes etc. The development of these components during production was monitored in chosen Edam cheese (fat 30% w/w using headspace-SPME-GC method. The samples were taken from cheesemilk up to technologically ripe cheese. In total 37 various organic compounds belonging to five chemical groups were identified in milk and cheese samples. Their total content increased during production. The first increase was observed after pressing and then especially in last part of ripening. Ethanol (185.8 ± 15.85 mg.kg−1, acetoin (97.7 ± 3.78 mg.kg−1, 2-methylpropanol (71.2 ± 5.23 mg.kg−1, acetic acid (54.4 ± 1.70 mg.kg−1 and acetaldehyde (36.4 ± 10.17 mg.kg−1 were the most abundant in ripened cheeses. The flavour and other organoleptic properties (appearance, texture of Edam cheese samples were also sensorially evaluated during ripening. The five point ordinal scale and profile tests were used for evaluation. The sensory quality was improved during ripening, until the final marked flavour characteristic for these cheese types.

  2. Partial purification and characterization of a bacteriocin produced by Enterococcus faecium 130 isolated from mozzarella cheese

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    Fabrício Luiz Tulini

    2011-03-01

    Full Text Available Lactic acid bacteria are important in foods as potential probiotics and also due to the ability to produce antimicrobial compounds that can contribute for biopreservation. In this work, the bacteriocin produced by the food isolate Enterococcus faecium 130 was partially purified and characterized. The compound was active against Gram-positive bacteria, including Listeria monocytogenes. It was produced after 4 days of storage at a broad temperature range (4 to 37 °C; it was stable at pH ranging from 2 to 10 with no loss of activity after heating at 100 °C for 15 minutes. Bacteriocin was partially purified by the adsorption-desorption technique, and the analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE showed a molecular mass of 3.5 to 6.5 kDa. These data encourage studies on application of this bacteriocin in food systems as an additional hurdle to microbial growth.

  3. Community dynamics of complex starter cultures for Gouda-type cheeses and its functional consequences

    NARCIS (Netherlands)

    Erkus, O.

    2014-01-01

    Lactic acid bacteria (LAB) are used as starter and adjunct cultures for the production of artisanal and industrial fermented milk products such as yoghurt and cheese. Artisanal fermentations is propagated with the transfer of an inoculum from old batch of fermented food to the new batch

  4. Characterization of non-starter lactic acid bacteria in traditionally produced home-made Radan cheese during ripening

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    Jokovic Natasa

    2011-01-01

    Full Text Available Two hundred thirteen non-starter lactic acid bacteria isolated from Radan cheese during ripening were identified with both a classical biochemical test and rep-PCR with (GTG5 primer. For most isolates, which belong to the Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides, Lactobacillus plantarum, Lactobacillus paraplantarum and Enterococcus faecium, a phenotypic identification was in good agreement with rep-PCR identification. Lactococeus lactis subsp. lactis, Enterococcus faecium and subspecies from the Lenconostoc mesenteroides group were the dominant population of lactic acid bacteria in cheese until 10 days of ripening and only one Streptococcus thermophilus strain was isolated from the 5-day-old cheese sample. As ripening progressed, Lactobacillus plantarum became the predominant species together with the group of heterofermentative species of lactobacilli that could not be precisely identified with rep-PCR.

  5. Use of artichoke (Cynara scolymus) flower extract as a substitute for bovine rennet in the manufacture of Gouda-type cheese: characterization of aspartic proteases.

    Science.gov (United States)

    Llorente, Berta E; Obregón, Walter David; Avilés, Francesc X; Caffini, Néstor O; Vairo-Cavalli, Sandra

    2014-09-15

    Artichoke (Cynara scolymus L.) flower extract was assayed with the aim of replacing animal rennet in the manufacture of Gouda-type cheeses from bovine milk. Floral extract coagulated milk within a suitable time for use on an industrial scale, while the yield of cheese obtained was equal to that achieved with bovine abomasum. Five proteolytic fractions with milk-clotting activity were isolated in a two-step purification protocol, three belonging to the cardosin group. Cheeses made with C. scolymus proteases must be brined for a longer period (40 h) to prevent overproteolysis and avoid the development of a background flavor. The type of coagulant (bovine or vegetable) had no significant effect on the cheeses' chemical parameters analyzed throughout ripening, and no significant organoleptic differences were detected between those manufactured with C. scolymus or animal rennet. The results indicate that C. scolymus flower extract is suitable for replacing animal rennet in the production of Gouda-type cheeses. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Controlled production of Camembert-type cheeses. Part I: Microbiological and physicochemical evolutions.

    Science.gov (United States)

    Leclercq-Perlat, Marie-Noëlle; Buono, Frédéric; Lambert, Denis; Latrille, Eric; Spinnler, Henry-Eric; Corrieu, Georges

    2004-08-01

    A holistic approach of a mould cheese ripening is presented. The objective was to establish relationships between the different microbiological and biochemical changes during cheese ripening. Model cheeses were prepared from pasteurized milk inoculated with Kluyveromyces lactis, Geotrichum candidum, Penicillium camemberti and Brevibacterium linens under aseptic conditions. Two cheese-making trials with efficient control of environmental parameters were carried out and showed similar ripening characteristics. K. lactis grew rapidly between days 1 and 6 (generation time around 48 h). G. candidum grew exponentially between days 4 and 10 (generation time around 4.6 d). Brevi. linens also grew exponentially but after day 6 when Pen. camemberti mycelium began developing and the pH of the rind was close to 7. Its exponential growth presented 3 phases in relation to carbon and nitrogen substrate availability. Concentrations of Pen. camemberti mycelium were not followed by viable cell count but they were evaluated visually. The viable microorganism concentrations were well correlated with the carbon substrate concentrations in the core and in the rind. The lactose concentrations were negligible after 10 d ripening, and changes in lactate quantities were correlated with fungi flora. The pH of the inner part depended on NH3. Surface pH was significantly related to NH3 concentration and to fungi growth. The acid-soluble nitrogen (ASN) and non-protein nitrogen (NPN) indexes and NH3 concentrations of the rind were low until day 6, and then increased rapidly to follow the fungi concentrations until day 45. The ASN and NPN indexes and NH3 concentrations in the core were lower than in the rind and they showed the same evolution. G. candidum and Pen. camemberti populations have a major effect on proteolysis; nevertheless, K. lactis and Brevi. linens cell lysis also had an impact on proteolysis. Viable cell counts of K. lactis, G. candidum, Pen. camemberti and Brevi. linens were

  7. Relating the effects of protein type and content in increased-protein cheese pies to consumers' perception of satiating capacity.

    Science.gov (United States)

    Marcano, J; Varela, P; Fiszman, S

    2015-02-01

    Since proteins have been shown to have the highest satiation-inducing effects of all the macronutrients, increasing the protein level is one of the main strategies for designing foods with enhanced satiating capacity. However, few studies analyze the effect that protein addition has on the texture and flavor characteristics of the target food item to relate it to the expected satiating capacity it elicits. The present work studied cheese pies with three levels of soy and whey proteins. Since the protein level altered the rheological behavior of the batters before baking and the texture of the baked pies, the feasibility of adding several protein levels for obtaining a range of final products was investigated. A check-all-that-apply questionnaire containing 32 sensory and non-sensory characteristics of the samples was given to consumers (n = 131) who also scored the perceived samples' satiating capacity. The results showed that the type and content of protein contributed distinctive sensory characteristics to the samples that could be related to their satiating capacity perception. Harder and drier samples (high protein levels) were perceived as more satiating with less perceptible sweet and milky cheese pie characteristic flavors. Soy contributed an off-flavour. These results will contribute to a better understanding of the interrelation of all these factors, aiding the development of highly palatable solid foods with enhanced satiating capacities.

  8. Selection of dairy culture and changes of Podravec cheese acidity during production

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    Slavko Kirin

    2002-06-01

    Full Text Available The selection and characteristics of dairy culture play a basic role in all types of cheese production process. The most important characteristic is acidification ability i.e. lactic acid formation, which regulates manufacturing and maturing conditions of cheese, thus affecting its organoleptic characteristics as well. In this work the results on control of acidity increase in Podravec cheeseproduction are presented. In the production process, a technical culture as well as identical frozen and concentrated culture, with and without auxiliary Streptococcus thermophilus for direct milk inoculation, were used. It was established that the acidity, expressed as pH value, is more intensively developed in cheeses produced with culture for direct inoculation. This was especially evident in the first phases of production i.e. before cheese salting. During salting the acidity of cheeses, in both cases, was almoust identical. Cheeses produced with identical frozen culture and auxiliary Streptococcus thermophilus culture had more pronounced acidity before salting and lower after salting in comparison with cheeses with the mentioned two cultures. Organoleptic and other characteristics of mature cheeses were identical.

  9. Microbial Diversity of a Camembert-Type Cheese Using Freeze-Dried Tibetan Kefir Coculture as Starter Culture by Culture-Dependent and Culture-Independent Methods

    Science.gov (United States)

    Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

    2014-01-01

    The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates). Meanwhile, Kazachstania servazzii (51 isolates) represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates). However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved) cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese. PMID:25360757

  10. Microbial diversity of a Camembert-type cheese using freeze-dried Tibetan kefir coculture as starter culture by culture-dependent and culture-independent methods.

    Directory of Open Access Journals (Sweden)

    Jun Mei

    Full Text Available The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR-denaturing gradient gel electrophoresis (DGGE analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates. Meanwhile, Kazachstania servazzii (51 isolates represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates. However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese.

  11. Microbial diversity of a Camembert-type cheese using freeze-dried Tibetan kefir coculture as starter culture by culture-dependent and culture-independent methods.

    Science.gov (United States)

    Mei, Jun; Guo, Qizhen; Wu, Yan; Li, Yunfei

    2014-01-01

    The biochemical changes occurring during cheese ripening are directly and indirectly dependent on the microbial associations of starter cultures. Freeze-dried Tibetan kefir coculture was used as a starter culture in the Camembert-type cheese production for the first time. Therefore, it's necessary to elucidate the stability, organization and identification of the dominant microbiota presented in the cheese. Bacteria and yeasts were subjected to culture-dependent on selective media and culture-independent polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) analysis and sequencing of dominant bands to assess the microbial structure and dynamics through ripening. In further studies, kefir grains were observed using scanning electron microscopy (SEM) methods. A total of 147 bacteria and 129 yeasts were obtained from the cheese during ripening. Lactobacillus paracasei represents the most commonly identified lactic acid bacteria isolates, with 59 of a total of 147 isolates, followed by Lactococcus lactis (29 isolates). Meanwhile, Kazachstania servazzii (51 isolates) represented the mainly identified yeast isolate, followed by Saccharomyces cerevisiae (40 isolates). However, some lactic acid bacteria detected by sequence analysis of DGGE bands were not recovered by plating. The yeast S. cerevisiae and K. servazzii are described for the first time with kefir starter culture. SEM showed that the microbiota were dominated by a variety of lactobacilli (long and curved) cells growing in close association with a few yeasts in the inner portion of the grain and the short lactobacilli were observed along with yeast cells on the exterior portion. Results indicated that conventional culture method and PCR-DGGE should be combined to describe in maximal detail the microbiological composition in the cheese during ripening. The data could help in the selection of appropriate commercial starters for Camembert-type cheese.

  12. Current knowledge of soft cheeses flavor and related compounds.

    Science.gov (United States)

    Sablé, S; Cottenceau, G

    1999-12-01

    Cheese aroma is the result of the perception of a large number of molecules belonging to different chemical classes. The volatile compounds involved in the soft cheese flavor have received a great deal of attention. However, there has been less work concerning the volatile compounds in the soft smear-ripened cheeses than in the mold-ripened cheeses. This paper reviews the components that contribute to the characteristic flavor in the soft cheeses such as surface-ripened, Camembert-type, and Blue cheeses. The sensory properties and quantities of the molecules in the different cheeses are discussed.

  13. The quality of processed cheeses and cheese analogues the same brand domestic and foreign production

    Directory of Open Access Journals (Sweden)

    Jana Bezeková

    2015-08-01

    Full Text Available Processed cheeses belong to Slovakia favorite dairy products. Processed cheeses are made from natural cheeses. In recent years the trend is to replace natural cheeses with other raw materials of non-dairy nature. The composition of the processed cheese analogues is not in many countries defined by legislation. The objective of this study was to determine and compare chemical properties (fat, dry matter, fat in dry matter, NaCl two samples of processed cheeses (C, D - Veselá krava and two samples cheese analogues (A, B - Kiri the same brand domestic and foreign production. The evaluated was taste of processed cheeses and cheese analogues, too. Chemical analysis and sensory analysis were repeated four times. The results of chemical analysis shows that all rated samples processed cheeses made on Slovakia fulfilled demands declared (dry matter and fat in dry matter as producers provided on the label. The most commonly fluctuate content of NaCl from 1 to 1.24 g.100g-1. The higher coefficient of variation in the determination of NaCl (3.88% was found in processed cheeses made in France. Processed cheese and cheese analogues made in France had not specified parameters for dry matter and fat in dry matter on the label. For production cheese analogues Kiri made in Slovakia was used different raw material than Kiri made in France. The taste of products was determined by descriptors - salty, slightly sweet, milky, buttery-creamy, fatty, sour, bitter, and unknown. The interesting that Kiri made in Slovakia had stronger milky and buttery-creamy taste than cheese analogue Kiri made in France. Significant differences were found in the slighty sweet taste of processed cheeses, the most points won processed cheese Veselá krava made in Slovakia.

  14. The effect of quality properties on Tulum cheese using different ...

    African Journals Online (AJOL)

    Cheese samples produced from pasteurized milk were found to have higher dry matter, fat and protein contents and acidity values than cheese samples produced from raw milk. No significant difference was found in the sensory properties of cheese produced from raw and pasteurized milk. In view of these findings, the use ...

  15. Cheese powder as an ingredient in emulsion sausages

    DEFF Research Database (Denmark)

    Chen, Xiang; Ruiz Carrascal, Jorge; Petersen, Mikael Agerlin

    2017-01-01

    Different types of cheese powder were added to meat emulsion sausages in order to address its influence on chemical composition, volatile compounds profile and sensory properties, and its potential to reduce salt content through boosting saltiness. Addition of cheese powder to emulsion sausages...... modified their profile of volatile compounds. Blue cheese increased some ketones, alcohols, and esters, while brown cheese brought typical Maillard reaction compounds. Overall, addition of cheese powders to sausages enhanced the intensity of flavour traits. A mixture of hard and blue cheese powder showed...... the highest effect on boosting saltiness, while brown cheese powder showed the strongest umami and meat flavour boosting effect, and sausages with added blue cheese powder showed a more intense aftertaste. Hardness significantly increased due to the addition of blue cheese powder. Addition of cheese powder...

  16. Dominance of rumen microorganisms during cheese whey acidification: acidogenesis can be governed by a rare Selenomonas lacticifex-type fermentation.

    Science.gov (United States)

    Ntougias, Spyridon; Tsiamis, George; Soultani, Despoina; Melidis, Paraschos

    2015-11-01

    The microbial basis of acidification process during spontaneous cheese whey wastewater fermentation was decrypted by implementing both culture-dependent and culture-independent techniques. Lac tobacillus and Bifidobacterium were the predominant taxa among the microbiota growing on MRS (deMan, Rogosa, and Sharpe), while Kazachstania unispora and Dekkera anomala yeast species were also isolated. Almost all Lactobacillus isolates were heterofermentative that could ferment glucose and lactose, with most of them being related to Lactobacillus hilgardii (99.0-100 % similarity). By employing fluorescence techniques, the dominance of long crescent-shaped bacteria in the acidogenic sludge was observed. Temperature gradient gel electrophoresis (TGGE), clone library, and next-generation sequencing techniques revealed the dominance of Selenomonas lacticifex. Based on Illumina data, Selenomonas in the continuous stirred-tank reactor (CSTR) represented 70.13 ± 4.64 % of the bacterial reads, while other Veillonellaceae taxa (Megasphaera and Pectinatus) represented a notable proportion (6.54 %). Prevotella was only detected by Illumina sequencing as an important constituent of the microbial population (14.97 ± 1.71 %). Budding yeasts represented 97 % of the fungal population in the CSTR, with Yarrowia strains representing 88.85 ± 5.52 % of the fungal reads. Spontaneous cheese whey acidification can favor the dominance of rumen bacteria and here was driven by the rarely reported S. lacticifex-type fermentation, which should be taken into consideration during evaluation of acidogenesis in process simulation and modelling. Moreover, the important nervonic acid content detected indicates that acidogenic sludge can be used as a source for the production of high value-added biomedical substrates.

  17. Formation of acrylamide in cheese bread

    DEFF Research Database (Denmark)

    Hedegaard, Rikke Susanne Vingborg; Sobrinho, Luis Gualberto De Andrade; Granby, Kit

    2008-01-01

    Low addition of grated Mozzarella cheese (13.4 g/100 g dough) resulted after baking for 20 min at 200 degrees C in a moderate increase of acrylamide from 4 ppb in buns without cheese to 7 ppb in the cheese buns as analyzed by a LCMS/MS technique. The effect was strongly dependent on the amount...... of cheese added, and addition of 23.7 g cheese resulted in 958 ppb acrylamide. For an o/w rapeseed oil emulsion as a food model heated under conditions similar to those persisting inside bread during baking, it was further shown that acrylamide formation also occurred in absence of reducing sugars....... In contrast, acrylamide was not observed in Pao de queijo a traditional Brazilian bread product made from fermented cassava flour, fresh eggs and a mixture of Brazilian Gouda type cheese and Mozzarella cheese pointing towards a role of eggs in protection against acrylamide formation....

  18. Bacteriocinogenic Lactococcus lactis subsp. lactis DF04Mi isolated from goat milk: Application in the control of Listeria monocytogenes in fresh Minas-type goat cheese

    Directory of Open Access Journals (Sweden)

    Danielle N. Furtado

    2015-03-01

    Full Text Available Listeria monocytogenes is a pathogen frequently found in dairy products. Its control in fresh cheeses is difficult, due to the psychrotrophic properties and salt tolerance. Bacteriocinogenic lactic acid bacteria (LAB with proven in vitro antilisterial activity can be an innovative technological approach but their application needs to be evaluated by means of in situ tests. In this study, a novel bacteriocinogenic Lactococcus lactis strain (Lc. lactis DF4Mi, isolated from raw goat milk, was tested for control of growth of L. monocytogenes in artificially contaminated fresh Minas type goat cheese during storage under refrigeration. A bacteriostatic effect was achieved, and counts after 10 days were 3 log lower than in control cheeses with no added LAB. However, this effect did not differ significantly from that obtained with a non-bacteriocinogenic Lc. lactis strain. Addition of nisin (12.5 mg/kg caused a rapid decrease in the number of viable L. monocytogenes in the cheeses, suggesting that further studies with the purified bacteriocin DF4Mi may open new possibilities for this strain as biopreservative in dairy products.

  19. Identification of a particular cheese production by trace analysis with nuclear techniques

    Science.gov (United States)

    Salvini, A.; Stroppa, A.; Cagnazzo, M.; Pappalardo, P.; Borio, A.; Manera, S.

    2006-05-01

    The counterfeit of a product, in this case a type of cheese, is an economic damage for the trade-mark product. An identification of the product itself by quantification of trace elements could be done. Nuclear techniques are useful and give good results. Some elements are connected to the process so different productions could be identified. Thirty elements and 160 spectrums are analysed. The samples of the same kind of cheese come from different countries and different Italian producers (15 different productions).

  20. Identification of a particular cheese production by trace analysis with nuclear techniques

    International Nuclear Information System (INIS)

    Salvini, A; Stroppa, A; Cagnazzo, M; Pappalardo, P; Borio, A; Manera, S

    2006-01-01

    The counterfeit of a product, in this case a type of cheese, is an economic damage for the trade-mark product. An identification of the product itself by quantification of trace elements could be done. Nuclear techniques are useful and give good results. Some elements are connected to the process so different productions could be identified. Thirty elements and 160 spectrums are analysed. The samples of the same kind of cheese come from different countries and different Italian producers (15 different productions)

  1. A New Probiotic Cheddar Cheese with High ACE-Inhibitory Activity and γ-Aminobutyric Acid Content Produced with Koumiss-Derived Lactobacillus casei Zhang

    Directory of Open Access Journals (Sweden)

    Hai Kuan Wang

    2010-01-01

    Full Text Available Cheddar cheese has been manufactured with Lactobacillus casei Zhang as the dairy starter adjunct. L. casei Zhang had previously been isolated from koumiss collected from Xilin Guole in Inner Mongolia and characterized in detail with regard to their probiotic potential. The addition of L. casei Zhang to Cheddar cheese had no adverse effects on sensory criteria. The cheese made with 0.1, 1 and 2 % of the probiotic strain L. casei Zhang adjuncts contained high levels of the Lactobacillus after 6 months of ripening with final counts of 9.6·10^7, 7.7·10^7 and 1.02·10^8 CFU/g, respectively. In the ripe control cheese, without the addition of probiotic strain L. casei Zhang, the number of Lactobacillus reached 5.7·107 CFU/g. Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR analysis was used to distinguish the added L. casei Zhang from the natural flora of the cheese and to determine whether L. casei Zhang grew in the cheese. ACE-inhibitory activity and γ-aminobutyric acid (GABA concentrations in the cheese were measured. Compared with control cheese, experimental cheese with 0.1, 1 and 2 % of probiotic strain L. casei Zhang revealed some increase in ACE-inhibitory activity and GABA mass fraction. In the present study, the production of both ACE-inhibitory activity and GABA in the probiotic cheese with the L. casei Zhang adjunct isolated from koumiss has been found for the first time. The results suggest that cheese with the probiotic strain L. casei Zhang showed good potential for application in the management of hypertension.

  2. Characteristics of cheeses manufactured using pepsin from adult ...

    African Journals Online (AJOL)

    Log in or Register to get access to full text downloads. ... (VP) was assessed using three types of cheeses namely Alpine, Tilister and Pastafilata (Pasta). ... pepsin waa an apprqpriate renner substitute for the small scale cheese processors.

  3. Reduced-fat Gouda-type cheese enriched with vitamin D3 effectively prevents vitamin D deficiency during winter months in postmenopausal women in Greece.

    Science.gov (United States)

    Manios, Yannis; Moschonis, George; Mavrogianni, Christina; van den Heuvel, Eghm; Singh-Povel, Cécile M; Kiely, Mairead; Cashman, Kevin D

    2017-10-01

    The primary aim of the present study was to examine the effectiveness of daily consumption of vitamin D 3 -enriched, reduced-fat Gouda-type cheese on 25-hydroxyvitamin D (25(OH)D) concentration in postmenopausal women. Health-related quality of life (HRQL) indices were examined as secondary outcomes. This is a single-blinded (i.e., to study participants), randomized, controlled food-based dietary intervention study. A sample of 79 postmenopausal women (55-75 years old) was randomized either to a control group (CG: n = 39) or an intervention group (IG: n = 40) that consumed, as part of their usual diet, 60 g of either non-enriched or vitamin D 3 enriched Gouda-type cheese, respectively, for eight consecutive weeks (i.e., from January to March 2015). Sixty grams of enriched cheese provided a daily dose of 5.7 μg of vitamin D 3 . There was a differential response of mean (95 % CI) serum 25(OH)D levels in the IG and CG, with the former increasing and the latter decreasing significantly over the eight weeks of the trial [i.e., by 5.1 (3.4, 6.9) nmol/L vs. -4.6 (-6.4, -2.8) nmol/L, P D levels  0.1). Consumption of 60 g of vitamin D 3 -enriched, reduced-fat Gouda-type cheese provided a daily dose of 5.7 μg of additional vitamin D 3 and was effective in increasing mean serum 25(OH)D concentration and in counteracting vitamin D deficiency during winter months in postmenopausal women in Greece.

  4. Influence of selected factors on browning of Camembert cheese.

    Science.gov (United States)

    Carreira, Alexandra; Dillinger, Klaus; Eliskases-Lechner, Frieda; Loureiro, Virgílio; Ginzinger, Wolfgang; Rohm, Harald

    2002-05-01

    Experimental Camembert cheeses were made to investigate the effects on browning of the following factors: inoculation with Yarrowia lipolytica, the use of Penicillium candidum strains with different proteolytic activity, the addition of tyrosine, and the addition of Mn2+ thus leading to 16 different variants of cheese. Two physical colour parameters were used to describe browning, depending on the location in the cheeses: a whiteness index for the outside browning (mould mycelium), and a brownness index for the inside browning (surface of the cheese body). Mn2+ promoted a significant increase of browning at both locations, whereas Yar. lipolytica had the opposite effect. Outside browning was significantly more intense when using the Pen. candidum strain with higher proteolytic activity. A significant interaction was found between Yar. lipolytica and Pen. candidum. The yeast had no effect in combination with a low proteolytic strain of Pen. candidum, but significantly reduced proteolysis and browning in combination with a high proteolytic strain of Pen. candidum. We further confirmed that both strains of Pen. candidum were able to produce brown pigments from tyrosine and thus both are presumably responsible for the browning activity in this type of cheese.

  5. Impact of heating on sensory properties of French Protected Designation of Origin (PDO) blue cheeses. Relationships with physicochemical parameters.

    Science.gov (United States)

    Bord, Cécile; Guerinon, Delphine; Lebecque, Annick

    2016-07-01

    The aim of this study was to measure the impact of heating on the sensory properties of blue-veined cheeses in order to characterise their sensory properties and to identify their specific sensory typology associated with physicochemical parameters. Sensory profiles were performed on a selection of Protected Designation of Origin (PDO) cheeses representing the four blue-veined cheese categories produced in the Massif Central (Fourme d'Ambert, Fourme de Montbrison, Bleu d'Auvergne and Bleu des Causses). At the same time, physicochemical parameters were measured in these cheeses. The relationship between these two sets of data was investigated. Four types of blue-veined cheeses displayed significantly different behaviour after heating and it is possible to discriminate these cheese categories through specific sensory attributes. Fourme d'Ambert and Bleu d'Auvergne exhibited useful culinary properties: they presented good meltability, stretchability and a weak oiling-off. However, basic tastes (salty, bitter and sour) are also sensory attributes which can distinguish heated blue cheeses. The relationship between the sensory and physicochemical data indicated a correlation suggesting that some of these sensory properties may be explained by certain physicochemical parameters of heated cheeses. © The Author(s) 2015.

  6. [Formation of nitrosamines in cheese products].

    Science.gov (United States)

    Klein, D; Keshavarz, A; Lafont, P; Hardy, J; Debry, G

    1980-01-01

    Several strains of micromycetes used as fermentation agents in the cheese industry or having led to accidents during cheese making are able to favor the formation of nitrosamines in 60% of the cases. The concentrations observed are similar to those found by other authors with other microorganisms. The results obtained in a semi-synthetic medium are checked during the ripening of experimental camembert type cheese made from milk containing nitrates and cultured with a strain of Penicillium camemberti, which favors very much the synthesis of nitrosamines. The amount of nitrosodimethylamine formed in this cheese increases from 5 to 20 ppb during ripening. A tentative explanation of the mechanism of formation is outlined.

  7. 21 CFR 133.190 - Spiced cheeses.

    Science.gov (United States)

    2010-04-01

    ... contains spices, in a minimum amount of 0.015 ounce per pound of cheese, and may contain spice oils. If the... lactic acid-producing bacterial culture. One or more of the clotting enzymes specified in paragraph (b)(2..., spices are added so as to be evenly distributed throughout the finished cheese. One or more of the other...

  8. 21 CFR 133.184 - Roquefort cheese, sheep's milk blue-mold, and blue-mold cheese from sheep's milk.

    Science.gov (United States)

    2010-04-01

    ..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE... cheese having the same physical and chemical properties. It is characterized by the presence of bluish... section may be warmed and is subjected to the action of a lactic acid-producing bacterial culture. One or...

  9. ComDim for explorative multi-block data analysis of Cantal-type cheeses: Effects of salts, gentle heating and ripening.

    Science.gov (United States)

    Loudiyi, M; Rutledge, D N; Aït-Kaddour, A

    2018-10-30

    Common Dimension (ComDim) chemometrics method for multi-block data analysis was employed to evaluate the impact of different added salts and ripening times on physicochemical, color, dynamic low amplitude oscillatory rheology, texture profile, and molecular structure (fluorescence and MIR spectroscopies) of five Cantal-type cheeses. Firstly, Independent Components Analysis (ICA) was applied separately on fluorescence and MIR spectra in order to extract the relevant signal source and the associated proportions related to molecular structure characteristics. ComDim was then applied on the 31 data tables corresponding to the proportion of ICA signals obtained for spectral methods and the global analysis of cheeses by the other techniques. The ComDim results indicated that generally cheeses made with 50% NaCl or with 75:25% NaCl/KCl exhibit the equivalent characteristics in structural, textural, meltability and color properties. The proposed methodology demonstrates the applicability of ComDim for the characterization of samples when different techniques describe the same samples. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Evaluation of using edible coating and ripening on Dangke, a traditional cheese of Indonesia

    Directory of Open Access Journals (Sweden)

    Malaka, R.

    2017-03-01

    Full Text Available Dangke is a traditional soft cheese from Enrekang, South Sulawesi Indonesia which is produced through heat denaturation at 85°C and enzymatic coagulation using papaya latex. The quality, microstructure and storage life of the cheese are affected by several factors such as denaturation temperature, enzyme concentration, moulding pressure, coating, and ripening. The objective of this study was to evaluated of using edible coating and ripening on Dangke cheese. The experiment was conducting using factorial design with five replications. The experimental variables were the type of edible coating used (agar, CMC and bee wax and the length of ripening (10, 20 and 30 days. Parameter was measured hardness, microstructure, and sensory evaluation. The overall result indicated that the use of edible coating can extend the shelf life, increase hardness, and more compact microstructure. Sensory evaluation also indicated that the cheese coated with film forming edible materials had had white color, more milk like smell (smelly milk, and smoother texture.

  11. Improved Properties and Microbiological Safety of Novel Cottage Cheese Containing Spices

    Directory of Open Access Journals (Sweden)

    Zvonimira Medverec Knežević

    2015-01-01

    Full Text Available The study focuses on developing novel cott age cheese containing spices with acceptable sensory properties, increased biological value and extended shelf life. Thirty types of cheese with added fresh or dried parsley, dill, pepper, garlic and rosemary were produced. Characterisation of phenolic compounds, antioxidant capacity and antibacterial activity of spices and cheese samples were evaluated. The cheese containing fresh pepper and fresh and dried herbs showed excellent sensory properties, with the best results obtained with fresh sweet red pepper. Dry rosemary had the highest antioxidant and antibacterial activity due to high mass fractions of caffeic and rosmarinic acids as well as high mass fractions of flavones and phenolic diterpenes. The plant extracts examined in vitro and in situ effectively reduce numbers of foodborne pathogens like Salmonella typhimurium, Escherichia coli, Staphylococcus aureus and Listeria monocytogenes, and therefore have potential as natural preservatives and antioxidants.

  12. Chemometrics approach to substrate development, case: semisyntetic cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose; Hansen, Birgitte Vedel

    1998-01-01

    from food production facilities.The Chemometrics approach to substrate development is illustrated by the development of a semisyntetic cheese substrate. Growth, colour formation and mycotoxin production of 6 cheese related fungi were studied on 9 types of natural cheeses and 24 synthetic cheese......, the most frequently occurring contaminant on semi-hard cheese. Growth experiments on the substrate were repeatable and reproducible. The substrate was also suitable for the starter P. camemberti. Mineral elements in cheese were shown to have strong effect on growth, mycotoxin production and colour...... formation of fungi. For P. roqueforti, P. discolor, P. verrucosum and Aspergillus versicolor the substrate was less suitable as a model cheese substrate, which indicates great variation in nutritional demands of the fungi. Substrates suitable for studies of specific cheese types was found for P. roqueforti...

  13. Cheese Classification, Characterization, and Categorization: A Global Perspective.

    Science.gov (United States)

    Almena-Aliste, Montserrat; Mietton, Bernard

    2014-02-01

    Cheese is one of the most fascinating, complex, and diverse foods enjoyed today. Three elements constitute the cheese ecosystem: ripening agents, consisting of enzymes and microorganisms; the composition of the fresh cheese; and the environmental conditions during aging. These factors determine and define not only the sensory quality of the final cheese product but also the vast diversity of cheeses produced worldwide. How we define and categorize cheese is a complicated matter. There are various approaches to cheese classification, and a global approach for classification and characterization is needed. We review current cheese classification schemes and the limitations inherent in each of the schemes described. While some classification schemes are based on microbiological criteria, others rely on descriptions of the technologies used for cheese production. The goal of this review is to present an overview of comprehensive and practical integrative classification models in order to better describe cheese diversity and the fundamental differences within cheeses, as well as to connect fundamental technological, microbiological, chemical, and sensory characteristics to contribute to an overall characterization of the main families of cheese, including the expanding world of American artisanal cheeses.

  14. A decision-making tool to determine economic feasibility and break-even prices for artisan cheese operations.

    Science.gov (United States)

    Durham, Catherine A; Bouma, Andrea; Meunier-Goddik, Lisbeth

    2015-12-01

    Artisan cheese makers lack access to valid economic data to help them evaluate business opportunities and make important business decisions such as determining cheese pricing structure. The objective of this study was to utilize an economic model to evaluate the net present value (NPV), internal rate of return, and payback period for artisan cheese production at different annual production volumes. The model was also used to determine the minimum retail price necessary to ensure positive NPV for 5 different cheese types produced at 4 different production volumes. Milk type, cheese yield, and aging time all affected variable costs. However, aged cheeses required additional investment for aging space (which needs to be larger for longer aging times), as did lower yield cheeses (by requiring larger-volume equipment for pasteurization and milk handling). As the volume of milk required increased, switching from vat pasteurization to high-temperature, short-time pasteurization was necessary for low-yield cheeses before being required for high-yield cheeses, which causes an additional increase in investment costs. Because of these differences, high-moisture, fresh cow milk cheeses can be sold for about half the price of hard, aged goat milk cheeses at the largest production volume or for about two-thirds the price at the lowest production volume examined. For example, for the given model assumptions, at an annual production of 13,608kg of cheese (30,000 lb), a fresh cow milk mozzarella should be sold at a minimum retail price of $27.29/kg ($12.38/lb), whereas a goat milk Gouda needs a minimum retail price of $49.54/kg ($22.47/lb). Artisan cheese makers should carefully evaluate annual production volumes. Although larger production volumes decrease average fixed cost and improve production efficiency, production can reach volumes where it becomes necessary to sell through distributors. Because distributors might pay as little as 35% of retail price, the retail price needs

  15. Physical properties of pizza Mozzarella cheese manufactured under different cheese-making conditions.

    Science.gov (United States)

    Banville, V; Morin, P; Pouliot, Y; Britten, M

    2013-08-01

    The effect of manufacturing factors on the shreddability and meltability of pizza Mozzarella cheese was studied. Four experimental cheeses were produced with 2 concentrations of denatured whey protein added to milk (0 or 0.25%) and 2 renneting pH values (6.4 or 6.5). The cheeses were aged 8, 22, or 36d before testing. Shreddability was assessed by the presence of fines, size of the shreds, and adhesion to the blade after shredding at 4, 13, or 22°C. A semi-empirical method was developed to measure the matting behavior of shreds by simulating industrial bulk packaging. Rheological measurements were performed on cheeses with and without a premelting treatment to assess melt and postmelt cheese physical properties. Lowering the pH of milk at renneting and aging the cheeses generally decreased the fines production during shredding. Adding whey protein to the cheeses also altered the fines production, but the effect varied depending on the renneting and aging conditions. The shred size distribution, adhesion to the blade, and matting behavior of the cheeses were adversely affected by increased temperature at shredding. The melting profiles obtained by rheological measurements showed that better meltability can be achieved by lowering the pH of milk at renneting or aging the cheese. The premelted cheeses were found to be softer at low temperatures (50°C) compared with the cheeses that had not undergone the premelting treatment. Understanding and controlling milk standardization, curd acidification, and cheese aging are essential for the production of Mozzarella cheese with desirable shreddability and meltability. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. 21 CFR 133.155 - Mozzarella cheese and scamorza cheese.

    Science.gov (United States)

    2010-04-01

    ... Section 133.155 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... procedure which produces a finished cheese having the same physical and chemical properties. It may be... culture. One or more of the clotting enzymes specified in paragraph (b)(2) of this section is added to set...

  17. [Subchronic toxicity testing of mold-ripened cheese].

    Science.gov (United States)

    Schoch, U; Lüthy, J; Schlatter, C

    1984-08-01

    The biological effects of known mycotoxins of Penicillium roqueforti or P. camemberti and other still unknown, but potentially toxic metabolites in mould ripened cheese (commercial samples of Blue- and Camembert cheese) were investigated. High amounts of mycelium (equivalents of 100 kg cheese/man and day) were fed to mice in a subchronic feeding trial. The following parameters were determined: development of body weight, organ weights, hematology, blood plasma enzymes. No signs of adverse effects produced by cheese mycotoxins could be detected after 28 days. No still unknown toxic metabolites could be demonstrated. From these results no health hazard from the consumption of mould ripened cheese, even in high amounts, appears to exist.

  18. Persistence of wild Streptococcus thermophilus strains on wooden vat and during the manufacture of a traditional Caciocavallo type cheese.

    Science.gov (United States)

    Settanni, L; Di Grigoli, A; Tornambé, G; Bellina, V; Francesca, N; Moschetti, G; Bonanno, A

    2012-04-02

    The present work was undertaken to evaluate the influence of the wooden dairy plant equipment on the microbiological characteristics of curd to be transformed into Caciocavallo Palermitano cheese. Traditional raw milk productions were performed concomitantly with standard cheese making trials carried out in stainless steel vat inoculated with a commercial starter. Milk from two different farms (A and B) was separately processed. The wooden vat was found to be a reservoir of lactic acid bacteria (LAB), while unwanted (spoilage and/or pathogenic) microorganisms were not hosted or were present at very low levels. All microbial groups were numerically different in bulk milks, showing higher levels for the farm B. LAB, especially thermophilic cocci, dominated the whole cheese making process of all productions. Undesired microorganisms decreased in number or disappeared during transformation, particularly after curd stretching. LAB were isolated from the wooden vat surface and from all dairy samples, subjected to phenotypic and genetic characterization and identification. Streptococcus thermophilus was the species found at the highest concentration in all samples analyzed and it also dominated the microbial community of the wooden vat. Fourteen other LAB species belonging to six genera (Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Streptococcus and Weissella) were also detected. All S. thermophilus isolates were genetically differentiated and a consortium of four strains persisted during the whole traditional production process. As confirmed by pH and the total acidity after the acidification step, indigenous S. thermophilus strains acted as a mixed starter culture. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Factors affecting consumers' preferences for and purchasing decisions regarding pasteurized and raw milk specialty cheeses.

    Science.gov (United States)

    Colonna, A; Durham, C; Meunier-Goddik, L

    2011-10-01

    Eight hundred ninety consumers at a local food festival were surveyed about their specialty cheese purchasing behavior and asked to taste and rate, through nonforced choice preference, 1 of 4 cheese pairs (Cheddar and Gouda) made from pasteurized and raw milks. The purpose of the survey was to examine consumers' responses to information on the safety of raw milk cheeses. The associated consumer test provided information about specialty cheese consumers' preferences and purchasing behavior. Half of the consumers tested were provided with cheese pairs that were identified as being made from unpasteurized and pasteurized milk. The other half evaluated samples that were identified only with random 3-digit codes. Overall, more consumers preferred the raw milk cheeses than the pasteurized milk cheeses. A larger portion of consumers indicated preferences for the raw milk cheese when the cheeses were labeled and thus they knew which samples were made from raw milk. Most of the consumers tested considered the raw milk cheeses to be less safe or did not know if raw milk cheeses were less safe. After being informed that the raw milk cheeses were produced by a process approved by the FDA (i.e., 60-d ripening), most consumers with concerns stated that they believed raw milk cheeses to be safe. When marketing cheese made from raw milk, producers should inform consumers that raw milk cheese is produced by an FDA-approved process. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  20. Enterocin HZ produced by a wild Enterococcus faecium strain isolated from a traditional, starter-free pickled cheese.

    Science.gov (United States)

    Yildirim, Zeliha; Bilgin, Harun; Isleroglu, Hilal; Tokatli, Kader; Sahingil, Didem; Yildirim, Metin

    2014-05-01

    Bacteriogenic Enterococcus faecium HZ was identified by using biochemical (Strep-API 20, API-50 CHL, fatty acid profile) and 16S rRNA analysis (99·99 %). Ent. faecium HZ was sensitive to clinically important antibiotics such as vancomycin, and did not have gelatinase and haemolysis activities. Enterocin HZ, a bacteriocin from Ent. faecium HZ, was sensitive to papain and tyripsin, but resistant to pepsin, lipase, catalase, α-amylase, organic solvents, detergents, ß-mercaptoethanol, and heat treatment (90 °C/30 min). It was biologically active at pH 2·0-9·0 and synthesised at the highest level in MRS or M17 broth at 32 or 37 °C with an inoculum amount of 0·1-0·5 % and an initial pH of 6·0-7·0. Enterocin HZ production reached maximum level at middle and late logarithmic phase and its molecular weight was ∼4·5 kDa. It was active against some Gram-positive foodborne bacteria. Ent. faecium HZ or its bacteriocin enterocin HZ is a good candidate to be studied as a food biopreservative since enterocin HZ showed strong bactericidal activity against Listeria monocytogenes in UHT milk and also Ent. faecium HZ grew very well in milk and produced enterocin HZ at maximum level.

  1. Characterization of different native american physalis species and evaluation of their processing potential as jelly in combination with brie-type cheese

    Directory of Open Access Journals (Sweden)

    Paula Nogueira CURI

    Full Text Available Abstract Faced with the need for greater knowledge of the different physalis species, the aim of this study was to characterize different Native American physalis species (Physalis peruviana L., Physalis pubescens L., Physalis angulata L., Physalis mínimos L. and Physalis ixocarpa Brot as to their physicochemical characteristics, bioactive compounds and antioxidant activity. Besides that, in order to increase their use and add even more value to this fruit, we also evaluate the influence of these different species on the physicochemical, rheological and sensory characteristics of physalis jelly. In addition, this study evaluated the sensory acceptance of the combination of physalis jellies obtained from different species with brie-type cheese. The Peruviana, Pubences and Angulata, are highlighted for being the nutritionally richest species, with the highest levels of phenolic compounds, vitamin C and antioxidant. Moreover, they stand out for originating the most widely sensory accepted jellies, either in pure form or in combination with brie-type cheese.

  2. Cheese / Eero Epner

    Index Scriptorium Estoniae

    Epner, Eero, 1978-

    2004-01-01

    Fotoajakirjast "Cheese". Fotograafia uurimisest, fotoajaloo läbikirjutatusest Eestis. Samas "Cheese'i" toimetaja Tiit Lepp ajakirja erainitsiatiivil väljaandmisest, Eesti Kultuurkapitali ebapiisavast ja määramatust toetusest

  3. Winter feeding systems and dairy cow breed have an impact on milk composition and flavour of two Protected Designation of Origin French cheeses.

    Science.gov (United States)

    Hurtaud, C; Peyraud, J L; Michel, G; Berthelot, D; Delaby, L

    2009-09-01

    This study investigates the effects of two feeding systems and two dairy cow breeds on milk yield and composition, physical and sensorial properties of Camembert and Pont-l'Evêque cheeses. The experiment consisted of a 2 × 2 factorial arrangement of treatments. A low energy grass diet with only 15% of concentrate (LowGS) was compared with a high-energy maize silage diet with 30% concentrate (HighMS). Thirty-four Holstein (Ho) and 34 Normande (No) cows in early lactation were assigned to one of two feeding systems for a 6-week period. Cows on the LowGS feeding system had lower milk yield, fat and protein content. In both feeding systems, No cows had lower milk yields but higher milk protein contents than Ho cows. The LowGS feeding system altered milk fatty acid (FA) composition by reducing saturated FA. Breed had only a small impact on milk FA. Concerning milk coagulating properties, only the firmness was reduced by the LowGS feeding and the Ho breed. The effects of breed and feeding system on the protein content of cheeses were more marked in Camembert cheese than in Pont-l'Evêque cheese. However, the Camembert cheese from Ho-LowGS was, in fact, characterized especially by lower protein content. LowGS feeding system and No breed produced more yellow cheeses. Feeding systems had limited effects on the firmness of Camembert and Pont-l'Evêque cheeses measured by penetrometry. In sensory analysis, Ho breed and LowGS feeding produced a Camembert cheese with a more melting texture in the mouth due to the increase of spreadability index and of proteolysis. The type of cheese also had an influence: the effects were more important on Camembert cheese than on Pont-l'Evêque cheese. Only the Ho-LowGS treatment produced a very specific Camembert cheese different from the others. The feeding systems and breed of dairy cow have no determinant effect on PDO (protected designation of origin) Camembert and Pont-l'Evêque cheeses, especially regarding taste. In this kind of

  4. Use of a genetically enhanced, pediocin-producing starter culture, Lactococcus lactis subsp. lactis MM217, to control Listeria monocytogenes in cheddar cheese

    NARCIS (Netherlands)

    Buyong, N; Kok, J; Luchansky, JB

    1998-01-01

    Cheddar cheese was prepared with Lactococcus lactis subsp, lactis MM217, a starter culture which contains pMC117 coding for pediocin PA-1, About 75 liters of pasteurized milk (containing ca, 3.6% fat) was inoculated with strain MM217 (ca, 10(6) CFU per ml) and a mixture of three Listeria

  5. Major defects in artisanal Minas cheese: a review

    Directory of Open Access Journals (Sweden)

    Denise Sobral

    2018-02-01

    Full Text Available The consumer’s preference for artisanal raw milk cheeses has been growing steadily, because of its taste intensity and variation compared to pasteurized cheese. The development of flavor and aroma in raw milk cheese is governed mainly by diversified endogenous microbiota and naturals milk enzymes. The weather, altitude, native pasture and others regional characteristics allow the artisanal Minas cheese to have a typical and unique flavor. However, most of artisanal cheeses are manufactured in a rudimentary way, following technologies used by their ancestor, and this fact can cause defects in cheeses, thus resulting in economic losses for producers. Many defects may be originated from the quality of milk for manufacture, as well as quality and quantity of the ingredients used, manufacturing and ripening procedures. In this review will be presented the major defects that arise specifically in artisanal cheeses, as well as their origins, prevention and repair.

  6. The science of cheese

    Science.gov (United States)

    The book describes the science of cheese in everyday language. The first chapters cover milk, mammals, and principles of cheesemaking and aging, along with lactose intolerance and raw milk cheese. Succeeding chapters deal with a category of cheese along with a class of compounds associated with it...

  7. Development of parmesan cheese production from local cow milk

    Science.gov (United States)

    Aliwarga, Lienda; Christianti, Elisabeth Novi; Lazarus, Chrisella

    2017-05-01

    Parmesan cheese is one of the dairy products which is used in various foods, such as pasta, bakery product, and pizza. It has a hard texture due to aging process for at least two years. Long aging period inhibited the production of parmesan cheese while consumer demands were increasing gradually. This research was conducted to figure out the effect of starter culture and rennet dose to the production of parmesan cheese. This research consists of (1) pasteurization of 1,500 ml milk at 73°C; and (2) main cheese making process that comprised of fermentation process and the addition of rennet. In latter stage, milk was converted into curd. Variations were made for the dose of bacteria culture and rennet. Both variables correlated to the fermentation time and characteristics of the produced cheese. The analysis of the produced cheese during testing stage included measured protein and cheese yield, whey pH, water activity, and moisture content. Moreover, an organoleptic test was done in a qualitative manner. The results showed that the dose of bacteria culture has a significant effect to the fermentation time, protein yield, and cheese yield. Meanwhile, rennet dose significantly affected cheese yield, pH of whey, and water activity. The highest protein yield (93.1%) was obtained at 0.6 ml of culture and 0.5 ml of rennet while the maximum cheese yield (6.81%) was achieved at 0.4 ml of culture and 0.1 ml of rennet. The water activity of produced cheeses was lower compared to the water activity of common parmesan cheese (ca. 0.6). For the organoleptic test, 0.4 ml of bacterial culture and 0.5 ml of rennet produced the most preferred cheese flavor compared to other variations.

  8. Proteolytic Activity in Reduced-Fat Cheddar Cheese Made with Lactic Acid Bacteria and Camel Chymosin

    DEFF Research Database (Denmark)

    Børsting, Mette Winther

    be the need of an extended ripening period to reach a similar cheese structure as in cheeses produced with BC. The aim of this project was to compensate for the lower proteolytic activity in cheese produced with CC compared to BC. Selection of dairy lactic acid bacteria (LAB) for cheese production with high....... lactis subsp lactis, 10 thermophilic Lactobacillus strains and 15 frozen direct vat set strains of thermopholic Lactobacillus) to hydrolyse αS1-CN, candidates were selected for cheese-making experiments. None of the selected proteolytic strains contributed significantly to softening the cheese structure...

  9. Toward the integration of expert knowledge and instrumental data to control food processes: application to Camembert-type cheese ripening.

    Science.gov (United States)

    Sicard, M; Perrot, N; Leclercq-Perlat, M-N; Baudrit, C; Corrieu, G

    2011-01-01

    Modeling the cheese ripening process remains a challenge because of its complexity. We still lack the knowledge necessary to understand the interactions that take place at different levels of scale during the process. However, information may be gathered from expert knowledge. Combining this expertise with knowledge extracted from experimental databases may allow a better understanding of the entire ripening process. The aim of this study was to elicit expert knowledge and to check its validity to assess the evolution of organoleptic quality during a dynamic food process: Camembert cheese ripening. Experiments on a pilot scale were carried out at different temperatures and relative humidities to obtain contrasting ripening kinetics. During these experiments, macroscopic evolution was evaluated from an expert's point of view and instrumental measurements were carried out to simultaneously monitor microbiological, physicochemical, and biochemical kinetics. A correlation of 76% was established between the microbiological, physicochemical, and biochemical data and the sensory phases measured according to expert knowledge, highlighting the validity of the experts' measurements. In the future, it is hoped that this expert knowledge may be integrated into food process models to build better decision-aid systems that will make it possible to preserve organoleptic qualities by linking them to other phenomena at the microscopic level. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. VIABILIDADE DE Escherichia coli PRODUTORA DE TOXINA SHIGA (STEC NÃO-O157 EM QUEIJO TIPO MINAS FRESCAL. VIABILITY OF NON-O157 SHIGA TOXIN-PRODUCING Escherichia coli (STEC IN MINAS FRESCAL CHEESE

    Directory of Open Access Journals (Sweden)

    Tammy Priscila Chioda

    2009-07-01

    Full Text Available Escherichia coli, produtora de toxina Shiga (STEC, um patógeno emergente capaz de causar diarreia, colite hemorrágica e síndrome hemolítica urêmica em humanos, representa um grave problema de saúde pública em todo o mundo. O principal reservatório de STEC são os bovinos. STEC são transmitidas aos humanos, principalmente através de alimentos contaminados, destacando-se aqueles de origem bovina como carne, leite e seus derivados. O objetivo deste trabalho foi avaliar a viabilidade de STEC não-O157 em queijo minas frescal preparado com leite artificialmente contaminado com diferentes cepas dessas bactérias. Os queijos foram mantidos a 4°C e analisados no 1º, 2º, 4º, 6º e 10º dias de estocagem. As cepas de STEC mantiveram-se viáveis em 100% (32/32 dos queijos mantidos sob refrigeração por até dez dias. Os resultados mostram que o queijo minas pode ser veículo de transmissão de STEC. Recomenda-se a adoção de métodos higiênicos e sanitários desde a ordenha até o processo de produção do queijo para reduzir a possibilidade de contaminação com STEC.

    PALAVRAS-CHAVES: PCR, queijo minas, segurança alimentar, STEC.

    Shiga toxin-producing Escherichia coli (STEC an emergent foodborne pathogen that cause diarrhea, hemorrhagic colitis and haemolytic uremic syndrome in humans, represents a public health problem all over the world. Cattle are the main source of STEC. STEC are transmitted to humans by contaminated food, mainly those of bovine origin as meat and dairy products. This study aimed evaluates the non-O157 STEC viability of artificially inoculated in the milk used for the Minas Frescal cheese’s production. The cheese was kept at 4°C and analyzed at 1st, 2nd, 4th, 6th and 10th days after its production. 100% (32/32 of the cheese storad under refrigeration during 10 days had been the STEC strains viable. These results show that minas frescal cheese can transmit STEC. The adoption of good

  11. Processamento do queijo coalho regional empregando leite pasteurizado e cultura lática endógena Manufacture of regional coalho type cheese by using pasteurized and standardized cow milk added with endogenous lactic acid culture

    Directory of Open Access Journals (Sweden)

    José Fernando Mourão Cavalcante

    2007-03-01

    Full Text Available O objetivo deste trabalho foi estabelecer uma proposta para o processamento do queijo Coalho regional seguindo-se os procedimentos adequados para a obtenção de um produto final de qualidade. Empregou-se leite de vaca padronizado e pasteurizado e culturas láticas endógenas. Foram isoladas, identificadas e caracterizadas culturas láticas endógenas de leite de vaca cru e de queijos Coalho artesanais. Algumas culturas foram avaliadas para a fabricação do queijo Coalho, seguindo-se o fluxograma de fabricação estabelecido neste estudo. O produto final foi submetido a análises físico-químicas, teste de aceitação e teste de fritura. Os resultados obtidos mostraram que é viável a padronização do produto tradicional, proporcionando redução de custos, qualidade microbiológica e a manutenção das características sensoriais do queijo Coalho regional, com o uso de culturas láticas nacionais.The main objective of this work is to propose a manufacturing procedure to make a safe artisan Coalho type cheese. Pasteurized and standardized cow´s milk added with endogenous lactic acid culture was used in the procedure. Endogenous lactic cultures were identified and characterized after being isolated from raw cow´s milk and artisan cheeses. The selected cultures were used in the manufacturing procedure designed for Coalho type cheese. Cheese made with added endogenous lactic acid culture underwent physic-chemical analysis, sensory acceptance and fritter tests. Results showed that it is feasible to make such cheese in a standardized process, with improved microbiological quality, keeping sensory properties of traditional cheese made with raw milk and a reduced cost using suppression on imports of starter cultures.

  12. LACTIC ACID BACTERIA FLORA OF KONYA KUFLU CHEESE: A TRADITIONAL CHEESE FROM KONYA PROVINCE IN TURKEY

    Directory of Open Access Journals (Sweden)

    Ziba Guley

    2014-12-01

    Full Text Available The aim of this study was to characterize the lactic acid bacteria flora of mature Konya Kuflu cheese. Konya Kuflu cheese is a traditional blue cheese which is produced from raw milk without starter culture addition and mould growth occurs in uncontrolled conditions during its ripening. Lactic acid bacteria (LAB isolated from 9 mature Konya Kuflu cheese samples were investigated using a combination of conventional biochemical tests, API test kits, and molecular approaches. For some isolates, different results were obtained according to the identification technique. The overall LAB profile of Konya Kuflu cheese samples revealed that Lactobacillus brevis, Lactobacillus paracasei/Lactobacillus casei, Lactobacillus plantarum, Enterococcus faecium, and Enterococcus faecalis are the predominant species. In addition, 1 Pediococcus parvulus and 1 Enterococcus durans were also identified.

  13. Major defects in artisanal Minas cheeses manufactured in the Canastra region

    Directory of Open Access Journals (Sweden)

    Denise Sobral

    2017-08-01

    been proposed and described in this article. It has also been verified that most of the cheese producers did not follow the minimum maturation period of 22 days required by de legislation and marketed the cheese still fresh.

  14. Determination of lactic acid bacteria in Kaºar cheese and ...

    African Journals Online (AJOL)

    Lactic acid bacteria (LAB) arise in Kaşar cheese, an artisanal pasta filata cheese produced in Turkey from raw milk without starter addition or pasteurized milk with starter culture. In this study, 13 samples of Kaşar cheese that were produced from raw milk were used as reference materials. LAB were characterized by using ...

  15. Artisanal Sonoran cheese (Cocido cheese): an exploration of its production process, chemical composition and microbiological quality.

    Science.gov (United States)

    Cuevas-González, Paúl F; Heredia-Castro, Priscilia Y; Méndez-Romero, José I; Hernández-Mendoza, Adrián; Reyes-Díaz, Ricardo; Vallejo-Cordoba, Belinda; González-Córdova, Aarón F

    2017-10-01

    The objective of this study was to explore and document the production process of artisanal Cocido cheese and to determine its chemical composition and microbiological quality, considering samples from six dairies and four retailers. Cocido cheese is a semi-hard (506-555 g kg -1 of moisture), medium fat (178.3-219.1 g kg -1 ), pasta filata-type cheese made from raw whole cow's milk. The production process is not standardized and therefore the chemical and microbiological components of the sampled cheeses varied. Indicator microorganisms significantly decreased (P pasteurize milk. Nevertheless, since Cocido cheese is a non-ripened, high-moisture product, it is a highly perishable product that could present a health risk if not properly handled. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. Marketing of the autochthonous dried cheese in Zagreb region

    Directory of Open Access Journals (Sweden)

    Marija Radman

    2004-04-01

    Full Text Available The demand for specific, value added food products is constantlyincreasing. In order to prepare such products for the market it is necessary to understand consumers’ attitudes and preferences towards food products. Dried cheese, one of the traditional products of wider Zagreb region is produced nowadays exclusively on the family farms without proper control of the used inputs and final product, and without any marketing activities. It is possible to add value and to increase the control of dried cheese production bydeveloping county brand of the cheese. The introduction of county brand of dried cheese in the market requires very good preparation in terms of fulfilling consumers’ needs and wishes. In this paper the results of the consumer survey are presented and could be used for the determination of the technological parameters of production and especially for marketing of the cheese and its distribution. The results showed that majority of the consumers prefer harder, compact, bright yellow cheese, with less intensive odour, packed in transparent plastic foil. Certain number of the respondents confused dried cheese with other cheeses sold in the market and therefore it is necessary to educate consumers about dried cheese and its characteristics compared to other cheeses.

  17. Bioconversion of Cheese Waste (Whey)

    Energy Technology Data Exchange (ETDEWEB)

    Bohnert, G.W.

    1998-03-11

    The US dairy industry produces 67 billion pounds of cheese whey annually. A waste by-product of cheese production, whey consists of water, milk sugar (lactose), casein (protein), and salts amounting to about 7% total solids. Ultrafiltration is used to concentrate cheese whey into a protein-rich foodstuff; however, it too produces a waste stream, known as ''whey permeate,'' (rejected water, lactose, and salts from the membrane). Whey permeate contains about 4.5% lactose and requires treatment to reduce the high BOD (biological oxygen demand) before disposal. Ab Initio, a small business with strong chemistry and dairy processing background, desired help in developing methods for bioconversion of whey permeate lactose into lactic acid. Lactic acid is an organic acid primarily used as an acidulant in the food industry. More recently it has been used to produce polylactic acid, a biodegradable polymer and as a new method to treat meat carcasses to combat E. coli bacteria. Conversion of whey permeate to lactic acid is environmentally sound because it produces a valued product from an otherwise waste stream. FM&T has expertise in bioconversion processes and analytical techniques necessary to characterize biomass functions. The necessary engineering and analytical services for pilot biomass monitoring, process development, and purification of crude lactic acid were available at this facility.

  18. Bioconversion of Cheese Waste (Whey)

    International Nuclear Information System (INIS)

    Bohnert, G.W.

    1998-01-01

    The US dairy industry produces 67 billion pounds of cheese whey annually. A waste by-product of cheese production, whey consists of water, milk sugar (lactose), casein (protein), and salts amounting to about 7% total solids. Ultrafiltration is used to concentrate cheese whey into a protein-rich foodstuff; however, it too produces a waste stream, known as ''whey permeate,'' (rejected water, lactose, and salts from the membrane). Whey permeate contains about 4.5% lactose and requires treatment to reduce the high BOD (biological oxygen demand) before disposal. Ab Initio, a small business with strong chemistry and dairy processing background, desired help in developing methods for bioconversion of whey permeate lactose into lactic acid. Lactic acid is an organic acid primarily used as an acidulant in the food industry. More recently it has been used to produce polylactic acid, a biodegradable polymer and as a new method to treat meat carcasses to combat E. coli bacteria. Conversion of whey permeate to lactic acid is environmentally sound because it produces a valued product from an otherwise waste stream. FM and T has expertise in bioconversion processes and analytical techniques necessary to characterize biomass functions. The necessary engineering and analytical services for pilot biomass monitoring, process development, and purification of crude lactic acid were available at this facility

  19. Cheese and cardiovascular health

    DEFF Research Database (Denmark)

    Hjerpsted, Julie Bousgaard

    Cardiovascular diseases (CVDs) are the number one cause of mortality worldwide. Low-density lipoprotein (LDL) cholesterol is a well-known risk factor of CVD which increases after the intake of saturated fatty acids (SFA). Cheese is a dietary product commonly consumed in Western countries and known...... to contain high amounts of SFA. However, cheese also contributes with several nutrients in the diet such as essential amino acids and calcium. The aim of this thesis was to examine the effect of cheese intake on CVD risk through evidence from both observational, intervention and explorative studies....... By reviewing results from published observational studies it was concluded that cheese does not seem to increase CVD risk, despite of the high SFA content of most cheeses. A human cross-over intervention study was conducted with the purpose of investigating the effect of hard cheese intake on risk markers...

  20. Functional genomics provides insights into the role of Propionibacterium freudenreichii ssp. shermanii JS in cheese ripening.

    Science.gov (United States)

    Ojala, Teija; Laine, Pia K S; Ahlroos, Terhi; Tanskanen, Jarna; Pitkänen, Saara; Salusjärvi, Tuomas; Kankainen, Matti; Tynkkynen, Soile; Paulin, Lars; Auvinen, Petri

    2017-01-16

    Propionibacterium freudenreichii is a commercially important bacterium that is essential for the development of the characteristic eyes and flavor of Swiss-type cheeses. These bacteria grow actively and produce large quantities of flavor compounds during cheese ripening at warm temperatures but also appear to contribute to the aroma development during the subsequent cold storage of cheese. Here, we advance our understanding of the role of P. freudenreichii in cheese ripening by presenting the 2.68-Mbp annotated genome sequence of P. freudenreichii ssp. shermanii JS and determining its global transcriptional profiles during industrial cheese-making using transcriptome sequencing. The annotation of the genome identified a total of 2377 protein-coding genes and revealed the presence of enzymes and pathways for formation of several flavor compounds. Based on transcriptome profiling, the expression of 348 protein-coding genes was altered between the warm and cold room ripening of cheese. Several propionate, acetate, and diacetyl/acetoin production related genes had higher expression levels in the warm room, whereas a general slowing down of the metabolism and an activation of mobile genetic elements was seen in the cold room. A few ripening-related and amino acid catabolism involved genes were induced or remained active in cold room, indicating that strain JS contributes to the aroma development also during cold room ripening. In addition, we performed a comparative genomic analysis of strain JS and 29 other Propionibacterium strains of 10 different species, including an isolate of both P. freudenreichii subspecies freudenreichii and shermanii. Ortholog grouping of the predicted protein sequences revealed that close to 86% of the ortholog groups of strain JS, including a variety of ripening-related ortholog groups, were conserved across the P. freudenreichii isolates. Taken together, this study contributes to the understanding of the genomic basis of P. freudenreichii

  1. Food safety hazards in Georgian Tushuri Guda cheese

    Directory of Open Access Journals (Sweden)

    Avtandil Korakhashvili

    2016-09-01

    Full Text Available Scientific-research work provides a timely and valuable review of the progress being made in the greater understanding of the factors contributing to Tushuri Guda cheese making and how this experience may be applied to producing better and more consistent products with food safety HACCP system requirements. The HACCP study in this variety of cheese covers all types of food safety hazards, like biological, chemical and physical, but unfortunately it needs a more precise definition. It did not include clarification of cleaning and sanitation operations in accordance with modern standards, sanitation of grasslands and meadows. All of that are covered by the plant Good Manufacturing Practices (GMPs procedures and Good Hygiene Practices (GHPs for the obtaining of maximal food safety results.

  2. A 100-Year Review: Cheese production and quality.

    Science.gov (United States)

    Johnson, M E

    2017-12-01

    In the beginning, cheese making in the United States was all art, but embracing science and technology was necessary to make progress in producing a higher quality cheese. Traditional cheese making could not keep up with the demand for cheese, and the development of the factory system was necessary. Cheese quality suffered because of poor-quality milk, but 3 major innovations changed that: refrigeration, commercial starters, and the use of pasteurized milk for cheese making. Although by all accounts cold storage improved cheese quality, it was the improvement of milk quality, pasteurization of milk, and the use of reliable cultures for fermentation that had the biggest effect. Together with use of purified commercial cultures, pasteurization enabled cheese production to be conducted on a fixed time schedule. Fundamental research on the genetics of starter bacteria greatly increased the reliability of fermentation, which in turn made automation feasible. Demand for functionality, machinability, application in baking, and more emphasis on nutritional aspects (low fat and low sodium) of cheese took us back to the fundamental principles of cheese making and resulted in renewed vigor for scientific investigations into the chemical, microbiological, and enzymatic changes that occur during cheese making and ripening. As milk production increased, cheese factories needed to become more efficient. Membrane concentration and separation of milk offered a solution and greatly enhanced plant capacity. Full implementation of membrane processing and use of its full potential have yet to be achieved. Implementation of new technologies, the science of cheese making, and the development of further advances will require highly trained personnel at both the academic and industrial levels. This will be a great challenge to address and overcome. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  3. Ripening-induced changes in microbial groups of artisanal Sicilian goats’ milk cheese

    Directory of Open Access Journals (Sweden)

    Vincenzo Di Marco

    2010-01-01

    Full Text Available Changes in the microbial flora of “Caprino dei Nebrodi”, a raw goat’s milk cheese produced in Sicily, were studied during ripening. From 2 batches of cheese, 4 samples were taken at day 0, 2, 15, and 30 of ripening. Also, samples of curd and milk used in the manufacturing process were analyzed. By the end of the ripening process (day 30, high log10 cfu/g were found for Lactobacilli (7.20, Lattococci (7.10, and Enterococci (7.00, whereas counts of Enterobacteriaceae (3.91, Escherichia coli (3.30, and Staphylococcus (3.89 were found to be lower. The study provides useful information on the microbiological properties of “Caprino dei Nebrodi” cheese, and the results obtained suggest that in order to increase the quality of this artisanal product, it is necessary to improve the sanitary conditions of milking and cheese-making. The study was intended as a preliminary step towards the isolation and identification of bacterial species found in this type of goat’s cheese.

  4. 60-day aging requirement does not ensure safety of surface-mold-ripened soft cheeses manufactured from raw or pasteurized milk when Listeria monocytogenes is introduced as a postprocessing contaminant.

    Science.gov (United States)

    D'Amico, Dennis J; Druart, Marc J; Donnelly, Catherine W

    2008-08-01

    Because of renewed interest in specialty cheeses, artisan and farmstead producers are manufacturing surface-mold-ripened soft cheeses from raw milk, using the 60-day holding standard (21 CFR 133.182) to achieve safety. This study compared the growth potential of Listeria monocytogenes on cheeses manufactured from raw or pasteurized milk and held for > 60 days at 4 degrees C. Final cheeses were within federal standards of identity for soft ripened cheese, with low moisture targets to facilitate the holding period. Wheels were surface inoculated with a five-strain cocktail of L. monocytogenes at approximately 0.2 CFU/ cm2 (low level) or 2 CFU/cm2 (high level), ripened, wrapped, and held at 4 degrees C. Listeria populations began to increase by day 28 for all treatments after initial population declines. From the low initial inoculation level, populations in raw and pasteurized milk cheese reached maximums of 2.96 +/- 2.79 and 2.33 +/- 2.10 log CFU/g, respectively, after 60 days of holding. Similar growth was observed in cheese inoculated at high levels, where populations reached 4.55 +/- 4.33 and 5.29 +/- 5.11 log CFU/g for raw and pasteurized milk cheeses, respectively. No significant differences (P milk types. Independent of the milk type, cheeses held for 60 days supported growth from very low initial levels of L. monocytogenes introduced as a postprocess contaminant. The safety of cheeses of this type must be achieved through control strategies other than aging, and thus revision of current federal regulations is warranted.

  5. Biogenic amines in Italian Pecorino cheese

    Directory of Open Access Journals (Sweden)

    Maria eSchirone

    2012-05-01

    Full Text Available The quality of distinctive artisanal cheeses is closely associated with the territory of production and its traditions. Pedoclimatic characteristics, genetic autochthonous variations and anthropic components create an environment so specific that it would be extremely difficult to reproduce elsewhere. Pecorino cheese is included in this sector of the market and is widely diffused in Italy (approximately 53.727t of production. Pecorino is a common name given to indicate Italian cheeses made exclusively from pure ewes' milk characterized by a high content of fat matter and it is mainly produced in the middle and south of Italy by traditional procedures from raw or thermized milk. The microbiota plays a major role in the development of the organoleptic characteristics of the cheese but it can also be responsible for the accumulation of undesirable substances, such as biogenic amines (BA. Several factors can contribute to the qualitative and quantitative profiles of BA’s in Pecorino cheese such as environmental hygienic conditions, pH, salt concentration, aw, fat content, pasteurization of milk, decarboxylase microorganisms, starter cultures, temperature and time of ripening, storage, part of the cheese (core, edge and the presence of cofactor. Generally, the total content of BA’s can range from about 100-2400 mg/kg, with a prevalence of toxicologically important BA’s, tyramine and histamine. The presence of BA in Pecorino cheeses is becoming increasingly important to consumers and cheese-maker alike, due to the potential threats of toxicity to humans and consequent trade implications.

  6. Queijo gorgonzola fabricado com leite pasteurizado por ejetor de vapor e HTST: parâmetros físico-químicos e sensoriais Gorgonzola type cheese manufactured with milk pasteurized by the HTST and steam ejector systems: physic-chemical and sensory parameters

    Directory of Open Access Journals (Sweden)

    Cristiane Gattini Sbampato

    2000-01-01

    Full Text Available Este trabalho teve como objetivo avaliar a influência de dois sistemas de pasteurização (High Temperature Short Time ¾ HTST¾ e ejetor de vapor nas características físico-químicas e sensoriais do queijo tipo Gorgonzola. As coletas de amostras de queijo e análises foram realizadas aos 5, 25, 45, 65 e 85 dias de maturação. Durante o período de maturação ocorreu aumento gradual de pH, sal/umidade e índice de acidez nos dois tratamentos. Os queijos fabricados com leite pasteurizado pelo sistema HTST obtiveram valores médios de pH superiores aos dos queijos fabricados com leite pasteurizado pelo sistema ejetor de vapor; os queijos fabricados com leite pasteurizado pelo sistema ejetor de vapor, obtiveram teores de índice de acidez e metilcetonas superiores aos dos queijos fabricados com leite pasteurizado pelo sistema HTST, indicando maior atividade lipolítica nesses queijos. Pela análise sensorial realizada aos 65 dias de maturação, pode se observar que não houve diferença significativa entre os tratamentos em relação à aparência, cor, consistência, textura e sabor. Porém foi observada diferença significativa com relação ao desenvolvimento do mofo e aroma. Os queijos fabricados com leite pasteurizado pelo sistema ejetor de vapor apresentaram maior atividade lipolítica e massa mais macia e fechada.The objective of this work was to evaluate the influence of two pasteurization systems (HTST and steam ejector on the physic-chemical and sensory characteristics of Gorgonzola type cheese. Sampling and analysis were conducted at 5, 25, 45, 65 and 85 days of ripening. Along the maturation period, pH, acidity index, salt/humidity, gradually increased. Cheeses manufactured with milk pasteurized by the HTST system had average values of pH higher than those manufactured with milk pasteurized by the steam ejector system. Milk pasteurized by the steam ejector system produced cheeses with higher acidity index (lipolysis and

  7. Cheese milk low homogenization enhanced early lipolysis and volatiles compounds production in hard cooked cheeses.

    Science.gov (United States)

    Vélez, María A; Hynes, Erica R; Meinardi, Carlos A; Wolf, Verónica I; Perotti, María C

    2017-06-01

    Homogenization applied to cheese milk has shown to increase lipolysis but its use is not spread as it can induce detrimental effects. The aim of this work was to assess the effect of low-pressure homogenization of the cream followed by pre-incubation of cheese milk on the composition, ripening index, lipolysis and volatile profiles of hard cooked cheeses. For that, control and experimental miniature Reggianito cheeses were made and analyzed during ripening (3, 45 and 90days). Homogenization had no impact on composition and proteolysis. An acceleration of the lipolysis reaction was clearly noticed in cheeses made with homogenized milk at the beginning of ripening, while both type of cheeses reached similar levels at 90days. We found the level of several compounds derived from fatty acid catabolism were noticeably influenced by the treatment applied: straight-chain aldehydes such as hexanal, heptanal and nonanal and methylketones from C 5 to C 9 were preferentially formed in experimental cheeses. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. 21 CFR 133.140 - Gammelost cheese.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... other procedure which produces a finished cheese having the same physical and chemical properties. The...) The dairy ingredients are subjected to the action of a lactic acid-producing bacterial culture. The...

  9. 21 CFR 133.141 - Gorgonzola cheese.

    Science.gov (United States)

    2010-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... produces a finished cheese having the same physical and chemical properties. It is characterized by the... this section may be warmed and is subjected to the action of a lactic acid-producing bacterial culture...

  10. 21 CFR 133.162 - Neufchatel cheese.

    Science.gov (United States)

    2010-04-01

    ... and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR... which produces a finished cheese having the same physical and chemical properties. The milkfat content... this section is subjected to the action of a harmless lactic acid-producing bacterial culture, with or...

  11. 21 CFR 133.181 - Provolone cheese.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... other method which produces a finished cheese having the same physical and chemical properties. It has a..., and is subjected to the action of a lactic acid-producing bacterial culture. One or more of the...

  12. Major advances in concentrated and dry milk products, cheese, and milk fat-based spreads.

    Science.gov (United States)

    Henning, D R; Baer, R J; Hassan, A N; Dave, R

    2006-04-01

    Advances in dairy foods and dairy foods processing since 1981 have influenced consumers and processors of dairy products. Consumer benefits include dairy products with enhanced nutrition and product functionality for specific applications. Processors convert raw milk to finished product with improved efficiencies and have developed processing technologies to improve traditional products and to introduce new products for expanding the dairy foods market. Membrane processing evolved from a laboratory technique to a major industrial process for milk and whey processing. Ultra-filtration and reverse osmosis have been used extensively in fractionation of milk and whey components. Advances in cheese manufacturing methods have included mechanization of the making process. Membrane processing has allowed uniform composition of the cheese milk and starter cultures have become more predictable. Cheese vats have become larger and enclosed as well as computer controlled. Researchers have learned to control many of the functional properties of cheese by understanding the role of fat and calcium distribution, as bound or unbound, in the cheese matrix. Processed cheese (cheese, foods, spreads, and products) maintain their importance in the industry as many product types can be produced to meet market needs and provide stable products for an extended shelf life. Cheese delivers concentrated nutrients of milk and bio-active peptides to consumers. The technologies for the production of concentrated and dried milk and whey products have not changed greatly in the last 25 yr. The size and efficiencies of the equipment have increased. Use of reverse osmosis in place of vacuum condensing has been proposed. Modifying the fatty acid composition of milkfat to alter the nutritional and functional properties of dairy spread has been a focus of research in the last 2 decades. Conjugated linoleic acid, which can be increased in milkfat by alteration of the cow's diet, has been reported to have

  13. Ripening for improving the quality of inoculated cheese Rhizopus oryzae

    Directory of Open Access Journals (Sweden)

    ARTINI PANGASTUTI

    2010-01-01

    Full Text Available Estikomah SA, Sutarno, Pangastuti A 2010. Ripening for improving the quality of inoculated cheese Rhizopus oryzae. Nusantara Bioscience 2: 1-6. Cheese is dairy product resulted from fermented milk in which the fermentation process can be done by lactic acid bacteria or fungus. Rhizopus oryzae is able to produce lactic acid, protease and lipase. The ripening process changes the taste and texture. The purpose of this study is ripening to improve the quality of inoculated cheese R. oryzae. In this research the ripening was conducted the concentration variation of temperature (5oC, 10oC, 15oC, and time (7 days, 14 days. The procedure of research consisted of two steps, namely un-ripened cheese preparation followed by ripening cheese preparation. Cheese produced in this study analyzed the value of pH, fat content, protein content, amino acid levels and identification of microbe with ANOVA then followed by DMRT at 5% level of significance. Data results were analyzed with the like’s nonparametric statistical test, followed by Fridman Wilcoxon Signed Rank Test (WSRT at 5% level significance. The results showed that the preferred ripened cheese panelist was at a temperature of 15oC for 14 days. Ripening conditions affect pH, fat content, protein content and do not affect the levels of amino acids that formed ripened cheese. The best quality ripened cheese i.e. at a temperature of 15°C for 14 days, had a pH value of 4.40, the highest protein content of 9.78%, and fat content of 35.02%. The results of identified microbe in un-ripened cheese and ripened cheese include Enterococcus hirae (Enterococcus faecalis, Bacillus subtilis, and Aspergillus sp.

  14. Occurrence of Listeria monocytogenes in cheese and ice cream produced in the State of Paraná, Brazil Ocorrência de Listeria monocytogenes em queijos e sorvetes produzidos no Estado do Paraná, Brasil

    Directory of Open Access Journals (Sweden)

    Wanda Moscalewski Abrahão

    2008-06-01

    Full Text Available The occurrence of Listeria monocytogenes in Brazilian ice cream and in some soft and semi-soft cheeses produced and sold in the State of Paraná, Brazil was evaluated. Ninety samples of cheese and sixty samples of ice creams were analyzed following the guidelines outlined by the official institutes, AOAC and FDA. In the ice cream samples no isolation of Listeria spp. was found. The percentage of these ninety samples of cheeses positive for Listeria spp. was 12.20%. Listeria monocytogenes was detected in six (6.70% of the same samples. The presence of Listeria innocua was five (5.50% in the samples analyzed was also observed. According to the results of the work it is possible to presume that there is a potential health risk to the brazilian population, heightened by aging and the increase in immunodepressed. These results indicate the need for the implementation of monitoring of these microorganisms as much by producers as by health inspectors. The results also show that the VIP (visual immunoprecipitation assay is a viable triage method of contaminated samples for the liberation of products for commercialization, as it is quick, reliable and does not require additional equipment other than that normally found in production labs, while presenting reliable results.A ocorrência de Listeria monocytogenes em sorvetes e alguns tipos de queijos macios e semi-macios produzidos e vendidos no Estado do Paraná Brasil foram avaliados. Noventa amostras de queijo e sessenta amostras de sorvete foram analisadas seguindo os protocolos da AOAC e FDA. Nas amostras de sorvete, não ocorreu o isolamento de Listeria spp. Foi detectada Listeria spp em 12,20% de amostras de queijo, das quais 6 (6,70% foram positivas para Listeria monocytogenes. Foi também observada a presença de Listeria innocua em 5 amostras (5,50% das mesmas amostras. Pelos resultados deste trabalho pode-se pressupor que existe um risco potencial à saúde da população brasileira com o

  15. Methane production from cheese whey

    Energy Technology Data Exchange (ETDEWEB)

    Yan, J Q; Liao, P H; Lo, K V

    1988-01-01

    Cheese whey was treated in a 17.5-litre laboratory-scale up-flow anaerobic sludge blanket reactor operated over a range of hydraulic retention times and organic loading rates. The reactor performance was determined in terms of methane production, volatile fatty acids conversion and chemical oxygen demand (COD) reduction. At a constant influent strength, the methane production rate decreased with decreasing hydraulic retention time. At constant hydraulic retention time the methane production rate increased as the influent strength was increased up to a concentration of 28.8 g COD litre/sup -1/. The methane production rate was similar for two influent concentrations studied at hydraulic retention times longer than 10 days. The effect of short hydraulic retention times on methane production rate was more pronounced for the higher influent concentration than for the lower influent concentration. The highest methane production rate of 9.57 litres CH/sub 4/ litre/sup -1/ feed day/sup -1/ was obtained at a loading rate of 5.96 g/sup -1/ COD litre/sup -1/ and an influent concentration of 28.8 g COD litre/sup -1/. A high treatment efficiency in terms of chemical oxygen demand reduction was obtained. In general, over 98% removal of chemical oxygen demand was achieved. The results indicated that anaerobic digestion of cheese whey using an upflow sludge blanket reactor could reduce pollution strength and produce energy for a cheese plant.

  16. Effect of temperature, pH, and water activity on Mucor spp. growth on synthetic medium, cheese analog and cheese.

    Science.gov (United States)

    Morin-Sardin, Stéphanie; Rigalma, Karim; Coroller, Louis; Jany, Jean-Luc; Coton, Emmanuel

    2016-06-01

    The Mucor genus includes a large number of ubiquitous fungal species. In the dairy environment, some of them play a technological role providing typical organoleptic qualities to some cheeses while others can cause spoilage. In this study, we compared the effect of relevant abiotic factors for cheese production on the growth of six strains representative of dairy technological and contaminant species as well as of a non cheese related strain (plant endophyte). Growth kinetics were determined for each strain in function of temperature, water activity and pH on synthetic Potato Dextrose Agar (PDA), and secondary models were fitted to calculate the corresponding specific cardinal values. Using these values and growth kinetics acquired at 15 °C on cheese agar medium (CA) along with three different cheese types, optimal growth rates (μopt) were estimated and consequently used to establish a predictive model. Contrarily to contaminant strains, technological strains showed higher μopt on cheese matrices than on PDA. Interestingly, lag times of the endophyte strain were strongly extended on cheese related matrices. This study offers a relevant predictive model of growth that may be used for better cheese production control but also raises the question of adaptation of some Mucor strains to the cheese. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Short communication: Little change takes place in Camembert-type cheese water activities throughout ripening in terms of relative humidity and salt.

    Science.gov (United States)

    Leclercq-Perlat, M-N; Hélias, A; Corrieu, G

    2013-01-01

    Water activity (a(w)) affects the growth and activity of ripening microorganisms. Moreover, it is generally accepted that a(w) depends on relative humidity (RH) and salt content; these 3 variables were usually measured on a given day in a cheese without the microorganism layer and without accounting for a distinction between the rind, the underrind, and the core. However, a(w) dynamics have never been thoroughly studied throughout cheese ripening. Experimental Camembert cheeses were ripened under controlled and aseptic conditions (temperature, gaseous atmosphere, and RH) for 14 d. In this study, only RH was varied. Samples were taken from the cheese (microorganism layer)-air interface, the rind, and the core. The aw of the cheese-air interface did not change over ripening when RH varied between 91 and 92% or between 97 and 98%. However, on d 5, we observed a small but significant increase in a(w), which coincided with the beginning of growth of Penicillium camemberti mycelia. After d 3, no significant differences were found between the a(w) of the cheese-air interface, the rind, and the core. From d 0 to 3, cheese rind a(w) increased from 0.94 to 0.97, which was probably due to the diffusion of salt from the rind to the core: NaCl content in the rind decreased from 3.7 to 1.6% and NaCl content in the core increased from 0.0 to 1.6%. Nevertheless, aw did not significantly vary in the core, raising questions about the real effect of salt on a(w).

  18. Overexpression of Lactobacillus casei D-hydroxyisocaproic acid dehydrogenase in cheddar cheese.

    Science.gov (United States)

    Broadbent, Jeffery R; Gummalla, Sanjay; Hughes, Joanne E; Johnson, Mark E; Rankin, Scott A; Drake, Mary Anne

    2004-08-01

    Metabolism of aromatic amino acids by lactic acid bacteria is an important source of off-flavor compounds in Cheddar cheese. Previous work has shown that alpha-keto acids produced from Trp, Tyr, and Phe by aminotransferase enzymes are chemically labile and may degrade spontaneously into a variety of off-flavor compounds. However, dairy lactobacilli can convert unstable alpha-keto acids to more-stable alpha-hydroxy acids via the action of alpha-keto acid dehydrogenases such as d-hydroxyisocaproic acid dehydrogenase. To further characterize the role of this enzyme in cheese flavor, the Lactobacillus casei d-hydroxyisocaproic acid dehydrogenase gene was cloned into the high-copy-number vector pTRKH2 and transformed into L. casei ATCC 334. Enzyme assays confirmed that alpha-keto acid dehydrogenase activity was significantly higher in pTRKH2:dhic transformants than in wild-type cells. Reduced-fat Cheddar cheeses were made with Lactococcus lactis starter only, starter plus L. casei ATCC 334, and starter plus L. casei ATCC 334 transformed with pTRKH2:dhic. After 3 months of aging, the cheese chemistry and flavor attributes were evaluated instrumentally by gas chromatography-mass spectrometry and by descriptive sensory analysis. The culture system used significantly affected the concentrations of various ketones, aldehydes, alcohols, and esters and one sulfur compound in cheese. Results further indicated that enhanced expression of d-hydroxyisocaproic acid dehydrogenase suppressed spontaneous degradation of alpha-keto acids, but sensory work indicated that this effect retarded cheese flavor development.

  19. Morphological, molecular, and mycotoxigenic identification of dominant filamentous fungi from moldy civil cheese.

    Science.gov (United States)

    Cakmakci, Songul; Cetin, Bulent; Gurses, Mustafa; Dagdemir, Elif; Hayaloglu, Ali Adnan

    2012-11-01

    Moldy Civil is a mold-ripened variety of cheese produced mainly in eastern Turkey. This cheese is produced with Civil cheese and whey curd cheese (Lor). Civil cheese has had a geographical presence since 2009 and is manufactured with skim milk. In the production of Moldy Civil cheese, Civil cheese or a mixture of Civil and Lor cheese is pressed into goat skins or plastic bags and ripened for 3 months or longer. During the ripening period, natural contaminating molds grow on the surface of and inside the cheese. In this study, 186 mold strains were isolated from 41 samples of Moldy Civil cheese, and 165 of these strains were identified as Penicillium roqueforti. Identification and mycotoxicologic analyses were conducted using morphotypic and molecular methods. PCR amplicons of the ITS1-5.8S-ITS4 region were subjected to sequence analysis. This research is the first using molecular methods on Moldy Civil cheese. Mycotoxicologic analyses were conducted using thin-layer chromatography, and random amplified polymorphic DNA genotypes were determined using the ari1 primer. Of 165 isolates, only 28 produced no penicillic acid, P. roqueforti toxin, or roquefortine.

  20. 21 CFR 133.146 - Grated cheeses.

    Science.gov (United States)

    2010-04-01

    ... Products § 133.146 Grated cheeses. (a) Description. Grated cheeses is the class of foods prepared by..., and skim milk cheese for manufacturing may not be used. All cheese ingredients used are either made... ___ cheese”, the name of the cheese filling the blank. (ii) If only parmesan and romano cheeses are used and...

  1. Acceptance and storage of fresh cheese made with essential oils

    Directory of Open Access Journals (Sweden)

    Joelmir Grassi Presente

    2017-08-01

    Full Text Available The aim of this work was to evaluate the acceptance and conservation of Minas fresh cheese with essential oils added of oregano and ginger in its formulation. The quality of the milk used as raw material was evaluated for pH, acidity, alizarol, total solids, density, and total microbial load. The cheeses produced were characterized as pH, acidity, moisture, lipids, proteins and ashes. The cheeses were also evaluated by sensorial affective tests using hedonic and attitude scales, in order to determine the acceptance and purchase intention by judges. The count of total aerobic mesophilic microorganisms was used to estimate the shelf-life of cheeses. The milk used as raw material is presented within the quality standards required by legislation. The cheeses made with essential oils showed pH and acidity around 6.9 and 0.87%, respectively, 57.6% moisture, 31.3% lipids, 11.4% protein and 0.9% ash. The cheese added essential oil of oregano and the control cheese were those given by the judges the best values for acceptance (7.5 and 7.6, respectively and purchase intention (4.2 and 4.4 respectively. Regarding the estimated shelf-life, the cheeses added essential oil of oregano and ginger had lower overall microbial load values compared to the control (no oil and mixed (two oils addition, presented counts values with up 106 UFC/g only from the 28th day of storage.

  2. 21 CFR 133.164 - Nuworld cheese.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... cheese having the same physical and chemical properties. It is characterized by the presence of creamy... this section may be warmed and is subjected to the action of a lactic acid-producing bacterial culture...

  3. 21 CFR 133.152 - Limburger cheese.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... a finished cheese having the same physical and chemical properties. The minimum milkfat content is... acid-producing bacterial culture. One or more of the clotting enzymes specified in paragraph (b)(2) of...

  4. 21 CFR 133.113 - Cheddar cheese.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... cheese having the same physical and chemical properties. The minimum milkfat content is 50 percent by... a lactic acid-producing bacterial culture. One or more of the clotting enzymes specified in...

  5. 21 CFR 133.133 - Cream cheese.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... a finished cheese having the same physical and chemical properties. The minimum milkfat content is... and is subjected to the action of lactic acid-producing bacterial culture. One or more of the clotting...

  6. 21 CFR 133.185 - Samsoe cheese.

    Science.gov (United States)

    2010-04-01

    ... Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN... cheese having the same physical and chemical properties. It has a small amount of eye formation of... this section may be warmed and is subjected to the action of a lactic acid-producing bacterial culture...

  7. 21 CFR 133.118 - Colby cheese.

    Science.gov (United States)

    2010-04-01

    ... coloring may be added. Sufficient rennet, or other safe and suitable milk-clotting enzyme that produces... of enzymes of animal or plant origin capable of aiding in the curing or development of flavor of.../catalase as provided in § 133.113(a)(3). (d)(1) Colby cheese in the form of slices or cuts may have added...

  8. Probiotic white cheese production using coculture with Lactobacillus species isolated from traditional cheeses

    Directory of Open Access Journals (Sweden)

    A. Ehsani

    2018-05-01

    Full Text Available Aim: The aim of the present study was to investigate the viability of lactic acid bacteria isolated from traditional cheeses and cocultured in Iranian white cheese during ripening. Materials and Methods: A total of 24 samples were isolated from 8 types of traditional cheeses in West Azerbaijan, Iran. Isolated species were cocultured with starter bacteria during the production of Iranian white cheese, and their viability was investigated up to 60 days of the refrigerated storage. Results: Of 118 isolates of Lactobacillus, 73 isolates (62% were confirmed as facultative heterofermentative and 45 isolates (38% as obligate homofermentative. Of the facultative heterofermentatives, 28 isolates (24% were Lactobacillus plantarum, 24 isolates (20% were Lactobacillus casei, and 21 isolates (18% were Lactobacillus agilis. Obligate homofermentatives were Lactobacillus delbrueckii (21%, Lactobacillus helveticus (14%, and Lactobacillus salivarius (3%. L. plantarum, L. casei and L. helveticus were found in high enough levels (106 CFU/g. Conclusion: According to the obtained data, it is recommended that complex starters such as L. helveticus, L. plantarum, and L. casei can be used in industrial productions of cheese to obtain exclusive properties of traditional cheeses.

  9. Fluorometric determination of histamine in cheese.

    Science.gov (United States)

    Chambers, T L; Staruszkiewicz, W F

    1978-09-01

    Thirty-one samples of cheese obtained from retail outlets were analyzed for histamine, using an official AOAC fluorometric method. The types of cheese analyzed and the ranges of histamine found were: colby, 0.3--2.8; camembert, 0.4--4.2; cheddar, 1.2--5.8; gouda, 1.3--2.4; provolone, 2.0--23.5; roquefort, 1.0--16.8; mozzarella 1.6--5.0; and swiss, 0.4--250 mg histamine/100 g. Ten of the 12 samples of swiss cheese contained less than 16 mg histamine/100 g. The remaining 2 samples which contained 116 and 250 mg histamine/100 g were judged organoleptically to be of poor quality. An investigation of one processing facility showed that the production of histamine in swiss cheese may have been a result of a hydrogen peroxide/low temperature treatment of the milk supply. Recovery of histamine added to methanol extracts of cheese ranged from 93 to 105%. Histamine content was confirmed by high pressure liquid chromatographic analysis of the methanol extracts.

  10. 21 CFR 133.169 - Pasteurized process cheese.

    Science.gov (United States)

    2010-04-01

    ...) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized Cheese and Related Products § 133.169 Pasteurized process cheese. (a)(1) Pasteurized process cheese is... two or more varieties, except cream cheese, neufchatel cheese, cottage cheese, lowfat cottage cheese...

  11. Increasing stringiness of low-fat mozzarella string cheese using polysaccharides.

    Science.gov (United States)

    Oberg, E N; Oberg, C J; Motawee, M M; Martini, S; McMahon, D J

    2015-07-01

    When fat content of pasta filata cheese is lowered, a loss of fibrous texture occurs and low-fat (LF) mozzarella cheese loses stringiness, making it unsuitable for the manufacture of string cheese. We investigated the use of various polysaccharides that could act as fat mimetics during the stretching and extruding process to aid in protein strand formation and increase stringiness. Low-fat mozzarella cheese curd was made, salted, and then 3.6-kg batches were heated in hot (80°) 5% brine, stretched, and formed into a homogeneous mass. Hot (80°C) slurries of various polysaccharides were then mixed with the hot cheese and formed into LF string cheese using a small piston-driven extruder. Polysaccharides used included waxy corn starch, waxy rice starch, instant tapioca starch, polydextrose, xanthan gum, and guar gum. Adding starch slurries increased cheese moisture content by up to 1.6% but was not effective at increasing stringiness. Xanthan gum functioned best as a fat mimetic and produced LF string cheese that most closely visually resembled commercial string cheese made using low-moisture part skim (LMPS) mozzarella cheese without any increase in moisture content. Extent of stringiness was determined by pulling apart the cheese longitudinally and observing size, length, and appearance of individual cheese strings. Hardness was determined using a modified Warner-Bratzler shear test. When LF string cheese was made using a 10% xanthan gum slurry added at ~1%, increased consumer flavor liking was observed, with scores after 2wk of storage of 6.44 and 6.24 compared with 5.89 for the LF control cheese; although this was lower than an LMPS string cheese that scored 7.27. The 2-wk-old LF string cheeses containing xanthan gum were considered still slightly too firm using a just-about-right (JAR) test, whereas the LMPS string cheese was considered as JAR for texture. With further storage up to 8wk, all of the LF string cheeses softened (JAR score was closer to 3

  12. Effect of Filling Type and Heating Method on Prevalence of Listeria species and Listeria monocytogenes in Dumplings Produced in Poland.

    Science.gov (United States)

    Szymczak, Barbara; Dąbrowski, Waldemar

    2015-05-01

    The count of Listeria monocytogenes was determined, before and after heat treatment, in 200 samples of dumplings of 9 brands and with different types of stuffing. Analyses were conducted according to ISO 11290-1 standard and with real-time PCR method. The highest count of L. monocytogenes was found in meat dumplings (10(2) to 10(4) CFU/g), whereas products with white cheese-potato stuffing and vegetable-mushroom stuffing contained significantly less Listeria, 20 to 80 and 5 to 32 CFU/g, respectively. In cooled meat dumplings the extent of contamination depended significantly on the producer. In addition, a significant (P monocytogenes in meat dumplings. In contrast, the microwave heating applied for 2 min at 600 W only reduced the count of L. monocytogenes by 1 to 2 logs. Hence, the microwave heating failed to reduce the risk of infection with this pathogen below the level permissible in the EU regulation, especially in the most contaminated samples. In this case, the efficacy of microwave heating was significantly (P monocytogenes (rho = 0.626), then by meat content in the stuffing (0.476), and to the lowest extent--by the type of meat (0.415 to 0.425). However, no Listeria sp. and L. monocytogenes were isolated from cooked dumplings with fruits (strawberries or blueberries). © 2015 Institute of Food Technologists®

  13. Selection of Leuconostoc strains isolated from artisanal Serrano Catarinense cheese for use as adjuncts in cheese manufacture.

    Science.gov (United States)

    Seixas, Felipe Nael; Rios, Edson Antônio; Martinez de Oliveira, André Luiz; Beloti, Vanerli; Poveda, Justa Maria

    2018-08-01

    Serrano Catarinense cheese is a raw bovine milk cheese produced in the region of Santa Catarina, Brazil. Twelve representative strains of Leuconostoc isolated from 20 samples of this artisanal cheese were selected and submitted for evaluation of the acidifying, proteolytic, autolytic, aminopeptidase and lipolytic activities, NaCl and acid resistance, production of dextran and biogenic amines and antimicrobial activity. The aim was to genetically and technologically characterize the Leuconostoc strains in order to use them in mixed starter cultures for cheese manufacture. Leuconostoc mesenteroides subsp. mesenteroides was the species that accounted for the largest proportion of isolates of Leuconostoc genus. Two leuconostoc isolates stood out in the acidifying activity, with reduction in pH of 1.12 and 1.04 units. The isolates showed low proteolytic and autolytic activity. Most of the isolates were dextran producers, presented good resistance to the salt and pH conditions of the cheese and showed antimicrobial activity against cheese pathogen bacteria, and none of them produced biogenic amines. These results allowed the selection of five strains (UEL 04, UEL 12, UEL 18, UEL 21 and UEL 28) as good candidates for use as adjunct cultures for cheese manufacture. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

  14. Minas-type fresh cheese developed from buffalo milk with addition of L. acidophilus Desenvolvimento de queijo minas frescal de leite de búfala com adição de L. acidophilus

    Directory of Open Access Journals (Sweden)

    Bruna Marcatti

    2009-08-01

    Full Text Available Effective incorporation of a probiotic into foods requires the culture to remain viable all along processing and storage, without adverse alterations to sensory characteristics. The objective of this work was developing Minas-type fresh cheese with probiotic properties from buffalo milk. Four batches of Minas-type fresh cheese were prepared using buffalo milk: batch T1 in which neither culture nor lactic acid added; batch T3 in which only lactic acid added; batches T2 and T4 , both added of Lactobacillus acidophilus LAC 4, but T4 was also acidified. Resulting cheeses were evaluated for probiotic culture stability, texture profile, sensory acceptance, and changes in pH. The T4 probiotic cheese presented hardness, gumminess, and chewiness significantly lower than the other treatments. However, values for springiness and cohesiveness did not differ between all cheeses, and no sensory differences (p > 0.05 were found between treatments for texture, taste, and overall acceptance. The addition of probiotic to the acidified cheese (T4 yielded best aroma. The populations of L. acidophilus were greater than 10(6 CFU g-1 after 28 days of storage all products. Minas-type fresh cheese from buffalo milk is a suitable food for the delivery of L. acidophilus, since the culture remained viable during the shelf life of the products and did not negative affect analysed parameters.Para incorporação efetiva de probióticos em alimentos é imprescindível que a cultura mantenha-se viável durante todo o processamento e a estocagem e que não ocorram alterações adversas nas características sensoriais do produto. O objetivo deste trabalho foi desenvolver queijo Minas frescal com propriedades probióticas a partir do leite de búfala. Foram avaliados quatro tratamentos (T1 a T4, sendo T1 e T3 controles, sem e com acidificação, respectivamente em T2 e T4 foram adicionados da cultura probiótica Lactobacillus acidophilus (LAC 4, porém T4 foi também acidificado

  15. Consensus categorization of cheese based on water activity and pH-A rational approach to systemizing cheese diversity.

    Science.gov (United States)

    Trmčić, A; Ralyea, R; Meunier-Goddik, L; Donnelly, C; Glass, K; D'Amico, D; Meredith, E; Kehler, M; Tranchina, N; McCue, C; Wiedmann, M

    2017-01-01

    been defined, these categories would represent safe havens for cheesemakers, which would allow cheesemakers to safely and legally produce raw milk cheeses that meet appropriate science-based safety requirements (e.g., risk to human health equivalent to pasteurized milk cheeses). Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. Producing infectious enterovirus type 71 in a rapid strategy

    Directory of Open Access Journals (Sweden)

    Qin E-De

    2010-06-01

    Full Text Available Abstract Background Enterovirus 71 (EV71 is an etiologic agent of hand-foot-and-mouth disease (HFMD, and recent HFMD epidemics worldwide have been associated with a severe form of brainstem encephalitis associated with pulmonary edema and high case-fatality rates. EV71 contains a positive-sense single-stranded genome RNA of approximately 7400 bp in length which encodes a polyprotein with a single open reading frame (ORF, which is flanked by untranslated regions at both the 5' and 3' ends. Results A long distance RT-PCR assay was developed to amplify the full length genome cDNA of EV71 by using specific primes carrying a SP6 promoter. Then the in vitro synthesized RNA transcripts from the RT-PCR amplicons were then transfected into RD cells to produce the rescued virus. The rescued virus was further characterized by RT-PCR and indirect fluorescent-antibody (IFA assay in comparison with the wild type virus. The rescued viruses were infectious on RD cells and neurovirulent when intracerebrally injected into suckling mice. Conclusions Thus, we established a rapid method to produce the infectious full length cDNA of EV71 directly from RNA preparations and specific mutations can be easily engineered into the rescued enterovirus genome by this method.

  17. Physicochemical and hygienic effects of Lactobacillus acidophilus in Iranian white cheese

    Directory of Open Access Journals (Sweden)

    Razzaqh Mahmoudi

    2012-09-01

    Full Text Available Increasing incidence of food-borne disease along with its social and economic consequences have led to conducting extensive research in order to produce safer food and develop new antimicrobial agents; among them, extensive use of probiotics and bacteriocins as biological additives is of significant importance. The aim of the present study was to evaluate the interactions (growth behavior and survival of Listeria monocytogenes and Lactobacillus acidophilus in various stages of production, ripening and storage of Iranian white cheese. Changes in pH values at different stages of cheese ripening, along with changes in organoleptic properties of cheese were also assessed. Compared to other treatments, in the treatment of cheese with probiotic agent without starter, the most significant decrease in Listeria monocytogenes count at the end of ripening stage was observed (3.16 Log per gram cheese compared with the control group (p < 0.05. Survival of probiotic bacteria in control samples of cheese were significantly higher when compared to cheese sample contaminated with Listeria (p < 0.05. White probiotic cheese with starter had the highest of sensory acceptability (p < 0.05. Listeria Monocytogenes count decreased during ripening period of probiotic white cheese but the bacteria survived in probiotic white cheese. Lactobacillus acidophilus count decreased during ripening period of white cheese but it did not lower to less than 106 CFU per g at the end of ripening and storage periods.

  18. Proteolysis in soft cheese, studied on Meshanger cheese and cheese models

    NARCIS (Netherlands)

    Noomen, A.

    1978-01-01

    Enzymes predominantly responsible for the primary degradation of protein in soft cheese and for the related changes in consistency were studied. Reconstructed Noordhollandse Meshanger cheese and preserved simulated soft cheeses of different composition were used as models in the

  19. Production and characterization of a functional Iranian white brined cheese by replacement of dairy fat with vegetable oils.

    Science.gov (United States)

    Achachlouei, B Fathi; Hesari, J; Damirchi, S Azadmard; Peighambardoust, Sh; Esmaiili, M; Alijani, S

    2013-10-01

    Full-fat cheese usually contains high amounts of saturated fatty acids and cholesterol, which may have negative health effects. In this study, full-fat white brined cheese, as a control sample, and experimental cheeses with olive and canola oils (T1, white brined cheese containing 50% canola oil, T2, white brined cheese containing 50% olive oil, T3, white brined cheese containing 100% canola oil and T4, white brined cheese containing 100% olive oil) were prepared from bovine milk. Physicochemical properties, lipolysis, proteolysis patterns and sensorial properties in the prepared samples were determined during 80 days of storage at 20-day intervals. Cheese incorporating vegetable oils showed lower amounts of saturated fatty acids and higher amounts of unsaturated fatty acids compared with the full-fat cheese (control) samples. Moisture, pH, lipolysis value, as assessed by the acid-degree value, and proteolysis values (pH 4.6 SN/TN% and NPN/TN%) significantly (p titrable acidity decreased during 40 days of ripening but then increased slightly. Sensory properties of white brined cheese incorporating with vegetable oils were different from those of full-fat cheese samples. White brined cheese containing olive and canola oils (100% fat substitution) received better sensory scores compared to other samples. The results showed that it is possible to replace dairy fat with olive and canola oils, which can lead to produce a new healthy and functional white brined cheese.

  20. Effect of wild strains used as starter cultures and adjunct cultures on the volatile compounds of the Pecorino Siciliano cheese.

    Science.gov (United States)

    Randazzo, C L; Pitino, I; De Luca, S; Scifò, G O; Caggia, C

    2008-03-20

    The effect of six wild strains on the volatile profile of the PS cheese was investigated and compared to that generated from industrial starters generally used to produce PS cheese. All cheeses were subjected to microbiological, physicochemical, and volatile compounds analyses. The DGGE of the 16S rDNA analysis was also applied. The volatile compounds generated during ripening were studied through the SPME and the GC-MS methods. No difference was detected between the experimental and control cheeses throughout chemical and microbiological analyses, while the DGGE results showed the presence of Streptococcus thermophilus in all cheeses, and the dominance of Enterococcus durans, Lactobacillus rhamnosus, and Lactobacillus casei in most of the experimental cheeses. Moreover, the presence of Lactococcus lactis species as in the control and in the experimental P2 and P4 cheeses was also revealed. The SPME results showed more pronounced volatile compounds in the experimental cheese samples than in the control ones.

  1. Performance of microbial fuel cell double chamber using mozzarella cheese whey substrate

    Science.gov (United States)

    Darmawan, M. D.; Hawa, L. C.; Argo, B. D.

    2018-03-01

    Nowadays the availability of electric energy is decreasing, hence there is a need for innovation of electric energy producer alternative; one of them is microbial fuel cell (MFC). MFC is a bioelectrochemical system generated by bacterial metabolism that utilizes organic substrate. One of the substrates that can be used is whey, a waste generated from cheese production. Therefore, this study aimed to determine the power of potential current and voltage generated from the use of whey cheese as a substrate for bacterial metabolism. In this research, double chamber system was used in microbial fuel cell reactor by using cheese whey as substrate at anode and potassium permanganate as cathode and utilizing membrane nafion 212 as membrane of proton exchange. The variable of experiment was bacteria type. The types of bacteria used in this study were Lactobacillus bulgaricus, Streptococcus thermophillus and Lactobacillus casei. While the operating time used was 100 hours. The highest current produced was 74.6 μA and the highest voltage was 529.3 mV produced by Lactobacillus bulgaricus bacteria. In this study, it was also found that the death phase of the three bacteria was at 70-80 hours.

  2. Production of Mozzarella Cheese Using Rennin Enzyme from Mucor miehei Grown at Rice Bran Molasses Medium

    Science.gov (United States)

    Rusdan, I. H.; Kusnadi, J.

    2017-04-01

    The research aimed to study the characteristic and yield of Mozzarella cheese produced by using rennin enzyme from Mucor miehei which is grown at rice bran and molasses medium. The popularity of Mozzarella cheese in Indonesia is increased caused by the spreading of western foods in Indonesia such as pizza and spaghetti that use Mozzarella cheese for ingredient. In Italy, Mozzarella and pizza cheeses are dominating 78% of the total Italian Cheese products. In producing Mozzarella cheese, rennin enzyme is always used as milk coagulant. Even now, Indonesia has not produced the rennin enzyme yet. The rennin enzyme from Mucor miehei growing at rice bran and molases medium which have the availability can be managed purposively within short period of time. The completly randomized design methode used to get the best crude extracts of Mucor miehei rennin enzyme, then is employed to produce mozzarella cheese. The result of Mozzarella cheese has various characteristics such as the yield’s weight is 9.1%, which consists of 50% moisture content, 36.64% peotein levels, 0.1 melting ability and 82.72% stretch ability or 0.79/N. With that characteristic it is concluded that rennin enzyme from Mucor miehei grown at rice bran molasses medium has the potential to alternatively subtitute calf rennin to produce Mozzarella cheese, and the characteristics fulfill the standart.

  3. Antioxidant activity and nutrient release from polyphenol-enriched cheese in a simulated gastrointestinal environment.

    Science.gov (United States)

    Lamothe, Sophie; Langlois, Ariane; Bazinet, Laurent; Couillard, Charles; Britten, Michel

    2016-03-01

    Green tea polyphenols are recognized for their antioxidant properties and their effects on lipid digestion kinetics. Polyphenols are sensitive to degradation in the intestinal environment. Interactions with dairy proteins could modulate the stability and biological activity of polyphenols during digestion. The objective of this study was to evaluate the release of nutrients (polyphenols, fatty acids and peptides) and the antioxidant activity in polyphenol-enriched cheese containing different levels of calcium in a simulated gastrointestinal environment. The relationship between cheese matrix texture, matrix degradation and nutrient release during digestion was also studied. Green tea extract was added to milk at 0% or 0.1%, and cheeses were produced on a laboratory scale. The level of available calcium was adjusted to low (Ca(low)), regular (Ca(reg)) or high (Ca(high)) during the salting step of the cheese-making process. Cheeses were subjected to simulated digestion. The rate and extent of fatty acid release were 21% lower for Ca(low) cheese than for Ca(reg) and Ca(high) cheeses. The greater adhesiveness of Ca(low) cheese, which resulted in lower rates of matrix degradation and proteolysis, contributed to the reduced rate of lipolysis. The presence of green tea extract in cheese reduced the release of free fatty acids at the end of digestion by 7%. The addition of green tea extract increased cheese hardness but did not influence matrix degradation or proteolysis profiles. The formation of complexes between tea polyphenols and proteins within the cheese matrix resulted in a more than twofold increase in polyphenol recovery in the intestinal phase compared with the control (tea polyphenol extract incubated with polyphenol-free cheese). Antioxidant activity was 14% higher in the digest from polyphenol-enriched cheese than in the control. These results suggest that cheese is an effective matrix for the controlled release of nutrients and for the protection of green

  4. Comparison of six commercial DNA extraction kits for detection of Brucella neotomae in Mexican and Central American-style cheese and other milk products.

    Science.gov (United States)

    Lusk, Tina S; Strain, Errol; Kase, Julie A

    2013-05-01

    Raw or inadequately pasteurized milk from infected animals and cheese made with such milk are a frequent vehicle for human brucellosis infection. Also, biological terrorism is a concern with certain Brucella spp. Due to matrix-associated real-time polymerase chain reaction (qPCR) inhibitors, robust sample preparations are crucial. We compared six commercial nucleic acid extraction kits using nine Mexican and Central American-style soft cheeses or creams and three liquid milk products inoculated with Brucella neotomae, a surrogate for pathogenic Brucella spp. Kits were evaluated by purity and quantity of DNA as determined by qPCR Ct values, reproducibility across cheese and milk types, and cost. At 10(7) CFU/g in four different cheeses, Qiagen statistically outperformed all other kits. When two cheese styles were inoculated at dual levels, Qiagen and High Pure kit extracted samples at 1.5 × 10(5) CFU/g produced average Ct values of 34-39, while PrepSEQ and MagMAX kit extracted samples exhibited higher or no Ct values. High Pure and Qiagen kits excelled also with liquid milk products. Considering matrices, inoculation levels, and kits evaluated, High Pure and Qiagen products produced Brucella DNA of high quality and quantity indicated by the lowest Ct values and were the least expensive. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Optimized enrichment for the detection of Escherichia coli O26 in French raw milk cheeses.

    Science.gov (United States)

    Savoye, F; Rozand, C; Bouvier, M; Gleizal, A; Thevenot, D

    2011-06-01

    Our main objective was to optimize the enrichment of Escherichia coli O26 in raw milk cheeses for their subsequent detection with a new automated immunological method. Ten enrichment broths were tested for the detection of E. coli O26. Two categories of experimentally inoculated raw milk cheeses, semi-hard uncooked cheese and 'Camembert' type cheese, were initially used to investigate the relative efficacy of the different enrichments. The enrichments that were considered optimal for the growth of E. coli O26 in these cheeses were then challenged with other types of raw milk cheeses. Buffered peptone water supplemented with cefixim-tellurite and acriflavin was shown to optimize the growth of E. coli O26 artificially inoculated in the cheeses tested. Despite the low inoculum level (1-10 CFU per 25 g) in the cheeses, E. coli O26 counts reached at least 5.10(4) CFU ml(-1) after 24-h incubation at 41.5 °C in this medium. All the experimentally inoculated cheeses were found positive by the immunological method in the enrichment broth selected. Optimized E. coli O26 enrichment and rapid detection constitute the first steps of a complete procedure that could be used in routine to detect E. coli O26 in raw milk cheeses. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  6. Microbial ecology of artisanal italian cheese: Molecular microbial characterization by culture-independent method

    International Nuclear Information System (INIS)

    Colombo, E.; Scarpellini, M.; Franzatti, L.; Dioguardi, L.

    2009-01-01

    Present study will treat the next topics: ecology of the natural and man made environments and functional diversity of bacteria. The microbial communities in artisanal goat cheeses produced in mountain pastures (typical farms) in Piemonte mountain (North of Italy) change a lot during precessing and ripening time. Moreover cheese microbial ecosystems are different in each small dairy because adventitious microflora can come from the environment and contamination the milk before the cheese making process and the product during manufacture and ripening. (Author)

  7. Microbial ecology of artisanal italian cheese: Molecular microbial characterization by culture-independent method

    Energy Technology Data Exchange (ETDEWEB)

    Colombo, E.; Scarpellini, M.; Franzatti, L.; Dioguardi, L.

    2009-07-01

    Present study will treat the next topics: ecology of the natural and man made environments and functional diversity of bacteria. The microbial communities in artisanal goat cheeses produced in mountain pastures (typical farms) in Piemonte mountain (North of Italy) change a lot during precessing and ripening time. Moreover cheese microbial ecosystems are different in each small dairy because adventitious microflora can come from the environment and contamination the milk before the cheese making process and the product during manufacture and ripening. (Author)

  8. Cardiometabolic Effects of Cheese Intake

    DEFF Research Database (Denmark)

    Thorning, Tanja Kongerslev

    In several countries, the dietary guidelines for preventing CVD focus on reducing the intake of saturated fat. A high cheese intake in particular may however not be associated with CVD risk, despite a high content of saturated fat. This could be due to a reduced digestibility of fat in cheese....... The aim of this PhD thesis was to investigate how the fat content of the cheese-matrix and the cheese ripening duration affect cardiometabolic risk markers and fecal fat excretion. The thesis is based on three intervention studies, two in pigs and one in humans. The results suggested that fat content...... of cheese-matrix may influence the HDL-cholesterol response, while the ripening duration may affect the level of free fatty acids and insulin in the blood. Furthermore the results showed that a diet with saturated fat in cheese or meat caused a higher HDL-cholesterol, but not LDL-cholesterol, compared...

  9. Bitter taste – cheese failure

    Directory of Open Access Journals (Sweden)

    Slavko Kirin

    2001-10-01

    Full Text Available Bitter taste is serous and very often cheese failure in modern cheesemaking process. In this paper the sources and bitter taste development in cheese will be presented. Bitterness in cheese is linked to bitter compounds development during cheese ripening. Most of the bitter compounds come from bitter peptides, the mechanism of theirs development being due to proteasepeptidase system of the cured enzymes and the milk cultures as well as other proteases present in cheese. By the action of curd enzymes, the milk protein - casein - is firstly degraded into high molecular weight compounds possessing no bitter taste. Those compounds are then degraded, by milk protease cultures, to hydrophobic bitter peptides of low molecular weight further degraded, by bacterial endopeptidase during cheese ripening, to bitter peptides and amino acids. In the case when no balance exists, between bitter compounds development and breakdown by lactic acid bacteria peptidase, an accumulation of bitter peptides occurs thus having an influence on cheese bitterness. During cheese ripening naturally occurring milk protease – plasmin, and thermostable proteases of raw milk microflora are also involved in proteolytic process. Fat cheese lipases, initiated by lipase originating from psychrotrophic bacteria in raw milk as well as other cheese lipases, are also associated with bitter taste generation. The other sources of bitterness come from the forages, the medicament residues as well as washing and disinfecting agents. In order to eliminate these failures a special care should be taken in milk quality as well as curd and milk culture selection. At this point technological norms and procedures, aimed to maintain the proteolysis balance during cheese ripening, should be adjusted, thus eliminating the bitter taste of the cheese.

  10. Manufacture and sensory analysis of reduced- and low-sodium Cheddar and Mozzarella cheeses.

    Science.gov (United States)

    Ganesan, Balasubramanian; Brown, Kelly; Irish, David A; Brothersen, Carl; McMahon, Donald J

    2014-01-01

    High sodium intake negatively affects consumer health, thus there is active interest in lowering sodium levels in dairy foods. Cheddar and low-moisture, part-skim Mozzarella cheeses were made with total salt levels of 0.7, 1.0, 1.25, 1.35, and 1.8% (wt/wt) in triplicate, thus reducing sodium by 25 to 60%. Multiple manufacturing protocols for salt reduction were used to produce cheeses with similar postpress moisture and pH, independent of the final salt levels in cheese, in order to study the role of salt in cheese acceptability. Cheese flavor was evaluated by a descriptive taste panel on a 15-point intensity scale. Consumer acceptance was evaluated by a consumer panel on a 9-point hedonic scale. Taste panels conducted with cubed Cheddar cheese (at 3 and 6mo) and cold shredded Mozzarella cheese (at 3wk) showed that consumer liking for cheese was low at 0.7 and 0.9% salt, but all cheeses containing higher salt levels (1.25, 1.35, and 1.8% salt) were comparably preferred. The cheeses had acceptable liking scores (≥6) when served as quesadilla or pizza toppings, and consumers were able to differentiate cheeses at alternate salt levels; for example, 1.8 and 1.5% salt cheeses scored similarly, as did cheeses with 1.5% and 1.35% salt, but 1.35% salt cheese scored lower than and was discernible from 1.8% salt cheese. Descriptive panelists perceived salty, sour, umami, bitter, brothy, lactone/fatty acid, and sulfur attributes as different across Mozzarella cheeses, with the perception of each significantly increasing along with salt level. Salty and buttery attributes were perceived more with increasing salt levels of Cheddar cheese by the descriptive panel at 3mo, whereas bitter, brothy, and umami attributes were perceived less at the higher salt levels. However, this trend reversed at 6mo, when perception of salty, sour, bitter, buttery, lactone/fatty acid, and umami attributes increased with salt level. We conclude that consumers can distinguish even a 30% salt

  11. Volatile compounds and sensory properties of Montasio cheese made from the milk of Simmental cows grazing on alpine pastures.

    Science.gov (United States)

    Bovolenta, S; Romanzin, A; Corazzin, M; Spanghero, M; Aprea, E; Gasperi, F; Piasentier, E

    2014-12-01

    The aim of this study was to analyze the volatile compounds, physicochemical characteristics, and sensory properties of Montasio, a semicooked pressed cheese, produced from the milk of the dual-purpose Italian Simmental cows grazing on alpine pastures. A total of 72 cows grazing on 2 pastures, which differed in botanical composition (nutrient-rich pasture vs. nutrient-poor pasture), received 2 different levels of supplementation (3.0 vs 1.5 kg/head per day). The experimental cheeses were produced from whole, raw milk and ripened for 60 d. Sixty-one volatile compounds, including alcohols (11), aldehydes (6), ketones (10), lactones (2), esters (6), hydrocarbons (3), carboxylic acids (6), phenolic compounds (4), monoterpenes (7), sesquiterpenes (1), sulfur compounds (4), and amines (1), were detected. The main families in terms of relative weight appeared to be carboxylic acids, esters, and alcohols. A panel of trained assessors described the experimental cheeses as having an intense color; small and evenly distributed eyes; an intense odor and flavor of milk-sour, milk, and cow; and a tender and creamy texture. The pasture type affected the volatile fraction, particularly ketones, phenolic compounds, and terpenes, which are overall higher in nutrient-poor pastures. A slight effect on the sensory analyses, in particular the effect of the cow attribute on odor and flavor, was perceived by the panelists. The cheeses produced on nutrient-rich pasture had higher b* (yellowness) index. These results were consistent with the color evaluation of the sensory panel. In addition, the pasture affected some textural attributes (adhesivity, creaminess, and granules) as perceived by the panelists. Concentrate supplementation, which is required to meet the feeding requirements of grazing cows, had no clear effect on either the volatile compounds or the sensory properties of the cheeses. Thus, at least within levels of integration adopted, it is expected not to alter the organoleptic

  12. Prevalence, types, and geographical distribution of Listeria monocytogenes from a survey of retail Queso Fresco and associated cheese processing plants and dairy farms in Sonora, Mexico.

    Science.gov (United States)

    Moreno-Enriquez, R I; Garcia-Galaz, A; Acedo-Felix, E; Gonzalez-Rios, I H; Call, J E; Luchansky, J B; Diaz-Cinco, M E

    2007-11-01

    In the first part of this study, samples were collected from farms, cheese processing plants (CPPs), and retail markets located in various geographical areas of Sonora, Mexico, over a 12-month period during the summer of 2004 and winter of 2005. Four (all Queso Fresco [QF] from retail markets) of 349 total samples tested positive for Listeria monocytogenes (Lm). Of these four positive samples, three were collected in the northern region and one in the southern region of Sonora. Additionally, two were collected during the winter months, and two were collected during the summer months. For the second part of the study, a total of 39 samples from a farm, a CPP, and retail markets were collected and processed according to a combination of the Norma Oficial Mexicana NOM-143-SSA1-1995.10 method (NOM) and the U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual method, and 27 samples from these same locations were collected and processed according to the U.S. Department of Agriculture Food Safety and Inspection Service method (USDA-FSIS). The NOM-FDA method recovered the pathogen from 6 (15%) of 39 samples (one cheese and five product contact surfaces), while the USDA-FSIS method recovered the pathogen from 5 (18.5%) of 27 samples (all product contact surfaces). In addition, the 40 isolates recovered from the 15 total samples that tested positive for Lm grouped into five distinct pulsotypes that were ca. 60% related, as determined by pulsed-field gel electrophoresis analysis. The results of this study confirmed a 3.4% prevalence of Lm in QF collected from retail markets located in Sonora and no appreciable difference in the effectiveness of either the NOM-FDA or USDA-FSIS method to recover the pathogen from cheese or environmental samples.

  13. Shifted excitation Raman difference spectroscopy for authentication of cheese and cheese analogues

    Science.gov (United States)

    Sowoidnich, Kay; Kronfeldt, Heinz-Detlef

    2016-04-01

    Food authentication and the detection of adulterated products are recent major issues in the food industry as these topics are of global importance for quality control and food safety. To effectively address this challenge requires fast, reliable and non-destructive analytical techniques. Shifted Excitation Raman Difference Spectroscopy (SERDS) is well suited for identification purposes as it combines the chemically specific information obtained by Raman spectroscopy with the ability for efficient fluorescence rejection. The two slightly shifted excitation wavelengths necessary for SERDS are realized by specially designed microsystem diode lasers. At 671 nm the laser (optical power: 50 mW, spectral shift: 0.7 nm) is based on an external cavity configuration whereas an emission at 783 nm (optical power: 110 mW, spectral shift: 0.5 nm) is achieved by a distributed feedback laser. To investigate the feasibility of SERDS for rapid and nondestructive authentication purposes four types of cheese and three different cheese analogues were selected. Each sample was probed at 8 different positions using integration times of 3-10 seconds and 10 spectra were recorded at each spot. Principal components analysis was applied to the SERDS spectra revealing variations in fat and protein signals as primary distinction criterion between cheese and cheese analogues for both excitation wavelengths. Furthermore, to some extent, minor compositional differences could be identified to discriminate between individual species of cheese and cheese analogues. These findings highlight the potential of SERDS for rapid food authentication potentially paving the way for future applications of portable SERDS systems for non-invasive in situ analysis.

  14. Industrial-scale application of Lactobacillus reuteri coupled with glycerol as a biopreservation system for inhibiting Clostridium tyrobutyricum in semi-hard ewe milk cheese.

    Science.gov (United States)

    Ávila, Marta; Gómez-Torres, Natalia; Delgado, David; Gaya, Pilar; Garde, Sonia

    2017-09-01

    The suitability of the biopreservation system formed by reuterin-producing L. reuteri INIA P572 and glycerol (required for reuterin production) to prevent late blowing defect (LBD) was evaluated in industrial sized semi-hard ewe milk cheese contaminated with Clostridium tyrobutyricum INIA 68, a wild strain isolated from a LBD cheese. For this purpose, six batches of cheese were made (three with and three without clostridial spores): control cheeses with lactococci starter, cheeses with L. reuteri as adjunct, and cheeses with L. reuteri and 30 mM glycerol. Spores of C. tyrobutyricum INIA 68 germinated during pressing of cheese curd, causing butyric acid fermentation in cheese after 30 d of ripening. The addition of L. reuteri, without glycerol, enhanced the symptoms and the formation of volatile compounds associated with LBD. When glycerol was added to cheese milk contaminated with C. tyrobutyricum, L. reuteri was able to produce reuterin in cheese resulting in cheeses with a uniform cheese matrix and a volatile profile similar to cheese made with L. reuteri and glycerol (without spores). Accordingly, L. reuteri INIA P572 coupled with glycerol seems a novel biopreservation system to inhibit Clostridium growth and prevent LBD by means of in situ reuterin production. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. The use of sanitation products in milk and cheese production

    Directory of Open Access Journals (Sweden)

    Samir Kalit

    2001-06-01

    Full Text Available Considering hygienic conditions in cheese production the aim of thispaper was to investigate the influence of using some sanitation* products in milk and cheese production on family farms. This investigation was a part of the project “Improving the quality of Tounj cheese produced on family farms”. By use of the sanitation products, during milk production, significant (P<0.01 decrease of geometrical mean of total bacterial count from 3.54 x 105 to 8 x 103 in mL of milk, as well as significant (P<0.01 decrease of geometric mean of somatic cell count from 3.1 x 105 to 2.4 x 105 in mL of milk was observed. The ratio of hygienically unacceptable cheeses, according to the Regulations of microbial standards for foods (NN 46/94., significantly (P<0.01 decreased as well. Because of the new requests and standards, the sanitation products are more in use in both milk and cheese production on family farms. Investigated sanitation products were suitable for use in milk and Tounj cheese production.

  16. Potential of anticlostridial Lactobacillus isolated from cheese to prevent blowing defects in semihard cheese

    DEFF Research Database (Denmark)

    Christiansen, Pia; Vogensen,, F. K.; Nielsen, E. W

    2010-01-01

    Five anticlostridial Lactobacillus strains isolated from cheese were selected for a mixed adjunct culture. Cheese with the mixed adjunct culture (experimental) and without (control) was made in triplicate and ripened as vacuum-packed and surface-ripened cheese. Cheese gross composition was similar....... Excessive gas formation occurred only in control cheeses. In contrast to control cheeses, the experimental cheeses were dominated by the added adjunct Lactobacillus strains (repetitive-PCR). Casein breakdown was not influenced, however, the total amount of amino acids and pH was slightly lower...... in the experimental cheeses. Anticlostridial nonstarter Lactobacillus strains have potential as protective adjunct cultures against blowing defects in cheese....

  17. Efficacy of UV-C irradiation for inactivation of food-borne pathogens on sliced cheese packaged with different types and thicknesses of plastic films.

    Science.gov (United States)

    Ha, Jae-Won; Back, Kyeong-Hwan; Kim, Yoon-Hee; Kang, Dong-Hyun

    2016-08-01

    In this study, the efficacy of using UV-C light to inactivate sliced cheese inoculated with Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes and, packaged with 0.07 mm films of polyethylene terephthalate (PET), polyvinylchloride (PVC), polypropylene (PP), and polyethylene (PE) was investigated. The results show that compared with PET and PVC, PP and PE films showed significantly reduced levels of the three pathogens compared to inoculated but non-treated controls. Therefore, PP and PE films of different thicknesses (0.07 mm, 0.10 mm, and 0.13 mm) were then evaluated for pathogen reduction of inoculated sliced cheese samples. Compared with 0.10 and 0.13 mm, 0.07 mm thick PP and PE films did not show statistically significant reductions compared to non-packaged treated samples. Moreover, there were no statistically significant differences between the efficacy of PP and PE films. These results suggest that adjusted PP or PE film packaging in conjunction with UV-C radiation can be applied to control foodborne pathogens in the dairy industry. Copyright © 2016. Published by Elsevier Ltd.

  18. Impact of fat reduction on flavor and flavor chemistry of Cheddar cheeses.

    Science.gov (United States)

    Drake, M A; Miracle, R E; McMahon, D J

    2010-11-01

    A current industry goal is to produce a 75 to 80% fat-reduced Cheddar cheese that is tasty and appealing to consumers. Despite previous studies on reduced-fat cheese, information is critically lacking in understanding the flavor and flavor chemistry of reduced-fat and nonfat Cheddar cheeses and how it differs from its full-fat counterpart. The objective of this study was to document and compare flavor development in cheeses with different fat contents so as to quantitatively characterize how flavor and flavor development in Cheddar cheese are altered with fat reduction. Cheddar cheeses with 50% reduced-fat cheese (RFC) and low-fat cheese containing 6% fat (LFC) along with 2 full-fat cheeses (FFC) were manufactured in duplicate. Cheeses were ripened at 8°C and samples were taken following 2 wk and 3, 6, and 9 mo for sensory and instrumental volatile analyses. A trained sensory panel (n=10 panelists) documented flavor attributes of cheeses. Volatile compounds were extracted by solid-phase microextraction or solvent-assisted flavor evaporation followed by separation and identification using gas chromatography-mass spectrometry and gas chromatography-olfactometry. Selected compounds were quantified using external standard curves. Sensory properties of cheeses were distinct initially but more differences were documented as cheeses aged. By 9 mo, LFC and RFC displayed distinct burnt/rosy flavors that were not present in FFC. Sulfur flavor was also lower in LFC compared with other cheeses. Forty aroma-active compounds were characterized in the cheeses by headspace or solvent extraction followed by gas chromatography-olfactometry. Compounds were largely not distinct between the cheeses at each time point, but concentration differences were evident. Higher concentrations of furanones (furaneol, homofuraneol, sotolon), phenylethanal, 1-octen-3-one, and free fatty acids, and lower concentrations of lactones were present in LFC compared with FFC after 9 mo of ripening. These

  19. Prevalence of Listeria monocytogenes in European cheeses

    DEFF Research Database (Denmark)

    Martinez Rios, Veronica; Dalgaard, Paw

    2017-01-01

    , respectively, pasteurized or un-pasteurized milk. Data from a total of 130,604 samples were analysed. Mean prevalence for presence during 2005-2015 estimated from scientific literature (2.3% with confidence interval (CI): 1.4-3.8%) was more than three times higher than results from EFSA reports (0.7%; CI: 0.......05) for cheeses produced from pasteurized (0.9%; CI: 0.4-1.9%) or un-pasteurized (1.0%; CI: 0.4-2.2%) milk. For cheese samples reported by EFSA 0.2% CI: 0.1-0.4% had concentration of L. monocytogenes above the critical European limits of 100 cfu/g. In addition, this systematic review focused on groups...

  20. 21 CFR 133.102 - Asiago fresh and asiago soft cheese.

    Science.gov (United States)

    2010-04-01

    ... finished cheese having the same physical and chemical properties as the cheese produced when the procedure... purified calcium chloride in a quantity not more than 0.02 percent (calculated as anhydrous calcium... benzoyl peroxide with potassium alum, calcium sulfate, and magnesium carbonate; but the weight of the...

  1. Extra Cheese, Please! Mozzarella's Journey from Cow to Pizza [and] Teaching Guide.

    Science.gov (United States)

    Peterson, Chris

    This book traces Annabelle the dairy cow's milk from the farm to the top of a Friday night pizza. The book relates that when Annabelle gives birth to her calf she also begins to produce milk; the milk is then processed into cheese, and from the cheese, pizza is made (recipe included). The book features color photographs of the entire process which…

  2. Bacteriological studies on Limburger cheese

    NARCIS (Netherlands)

    El-Erian, A.F.M.

    1969-01-01

    A study has been made of the ripening process of Limburger cheese, including microbiological investigations of the surface flora and chemical analyses of the cheese during the different stages of ripening. The microbial flora was studied both qualitatively and quantitatively. In addition to the

  3. Lipolysis and proteolysis profiles of fresh artisanal goat cheese made with raw milk with 3 different fat contents.

    Science.gov (United States)

    Sánchez-Macías, D; Morales-Delanuez, A; Moreno-Indias, I; Hernández-Castellano, L E; Mendoza-Grimón, V; Castro, N; Argüello, A

    2011-12-01

    The objective of this study was to describe the proteolysis and lipolysis profiles in goat cheese made in the Canary Islands (Spain) using raw milk with 3 different fat contents (0.5, 1.5, and 5%) and ripened for 1, 7, 14, and 28 d. β-Casein was the most abundant protein in all cheeses and at all ripening times. Quantitative analysis showed a general decrease in caseins as ripening progressed, and degradation rates were higher for α(S1)-casein than for β-casein and α(S2)-casein. Furthermore, the degradation rate during the experimental time decreased with lower fat contents. The α(S2)-casein and α(S1)-casein levels that remained in full-fat and reduced-fat cheeses were less than those in low-fat cheese. In contrast, β-casein also showed degradation along with ripening, but differences in degradation among the 3 cheese types were not significant at 28 d. The degradation products increased with the ripening time in all cheeses, but they were higher in full-fat cheese than in reduced-fat and low-fat cheeses. The free fatty acid concentration per 100g of cheese was higher in full-fat cheese than in reduced- and low-fat cheese; however, when the results were expressed as milligrams of free fatty acids per gram of fat in cheese, then lipolysis occurred more rapidly in low-fat cheese than in reduced- and full-fat cheeses. These results may explain the atypical texture and off-flavors found in low-fat goat cheeses, likely the main causes of non-acceptance. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  4. Biodiversity of bacterial ecosystems in traditional Egyptian Domiati cheese.

    Science.gov (United States)

    El-Baradei, Gaber; Delacroix-Buchet, Agnès; Ogier, Jean-Claude

    2007-02-01

    Bacterial biodiversity occurring in traditional Egyptian soft Domiati cheese was studied by PCR-temporal temperature gel electrophoresis (TTGE) and PCR-denaturing gradient gel electrophoresis (DGGE). Bands were identified using a reference species database (J.-C. Ogier et al., Appl. Environ. Microbiol. 70:5628-5643, 2004); de novo bands having nonidentified migration patterns were identified by DNA sequencing. Results reveal a novel bacterial profile and extensive bacterial biodiversity in Domiati cheeses, as reflected by the numerous bands present in TTGE and DGGE patterns. The dominant lactic acid bacteria (LAB) identified were as follows: Leuconostoc mesenteroides, Lactococcus garvieae, Aerococcus viridans, Lactobacillus versmoldensis, Pediococcus inopinatus, and Lactococcus lactis. Frequent non-LAB species included numerous coagulase-negative staphylococci, Vibrio spp., Kocuria rhizophila, Kocuria kristinae, Kocuria halotolerans, Arthrobacter spp./Brachybacterium tyrofermentans. This is the first time that the majority of these species has been identified in Domiati cheese. Nearly all the dominant and frequent bacterial species are salt tolerant, and several correspond to known marine bacteria. As Domiati cheese contains 5.4 to 9.5% NaCl, we suggest that these bacteria are likely to have an important role in the ripening process. This first systematic study of the microbial composition of Domiati cheeses reveals great biodiversity and evokes a role for marine bacteria in determining cheese type.

  5. Improvement in melting and baking properties of low-fat Mozzarella cheese.

    Science.gov (United States)

    Wadhwani, R; McManus, W R; McMahon, D J

    2011-04-01

    Low-fat cheeses dehydrate too quickly when baked in a forced air convection oven, preventing proper melting on a pizza. To overcome this problem, low-fat Mozzarella cheese was developed in which fat is released onto the cheese surface during baking to prevent excessive dehydration. Low-fat Mozzarella cheese curd was made with target fat contents of 15, 30, 45, and 60 g/kg using direct acidification of the milk to pH 5.9 before renneting. The 4 portions of cheese curd were comminuted and then mixed with sufficient glucono-δ-lactone and melted butter (45, 30, 15, or 0 g/kg, respectively), then pressed into blocks to produce low-fat Mozzarella cheese with about 6% fat and pH 5.2. The cheeses were analyzed after 15, 30, 60, and 120 d of storage at 5°C for melting characteristics, texture, free oil content, dehydration performance, and stretch when baked on a pizza at 250°C for 6 min in a convection oven. Cheeses made with added butter had higher stretchability compared with the control cheese. Melting characteristics also improved in contrast to the control cheese, which remained in the form of shreds during baking and lacked proper melting. The cheeses made with added butter had higher free oil content, which correlated (R2≥0.92) to the amount of butterfat added, and less hardness and gumminess compared with the control low fat cheese. Copyright © 2011 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  6. Dominant lactic acid bacteria in artisanal Pirot cheeses of different ripening period

    Directory of Open Access Journals (Sweden)

    Terzić-Vidojević Amarela

    2009-01-01

    Full Text Available In this study two raw cow's milk cheeses of a different ripening period were examined. The cheeses were taken from a country household in the region of mountain Stara Planina and manufactured without adding of starter culture. A total 106 lactic acid bacteria (LAB strains were isolated from both cheeses. They are tested by classical physiological tests as well as by API 50 CH tests. Proteolytic and antimicrobial activities were done too. Identification of LAB isolates was done by repetitive extragenic palindromic-polimerase chain reaction (rep-PCR with (GTG5 primer. The LAB isolates from cheese BGPT9 (four days old belonged to the eight species of LAB (Lactobacillus plantarum, Lactobacillus paracasei subsp. paracasei, Lactobacillus delbrueckii, Lactobacillus brevis, Enterococcus faecium, Enterococcus faecalis, Enterococcus durans and Leuconostoc garlicum, while in the BGPT10 cheese (eight months old only two species were present (Lactobacillus plantarum and Enterococcus faecium. Proteolytic activity showed 30 LAB from BGPT9 cheese, mainly enterococci. From BGPT10 cheese only one isolate (which belonged to the Lactobacillus plantarum species possessed partial ability to hydrolyze β-casein. Seven enterococci from BGPT9 cheese and four enterococci from BGPT10 cheese produced antimicrobial compounds.

  7. Antimicrobial activity of essential oils against Staphylococcus aureus in fresh sheep cheese

    Directory of Open Access Journals (Sweden)

    Simonetta Amatiste

    2014-08-01

    Full Text Available Essential oils (EOs are aromatic oily liquids extracted from different parts of specific plants, well known especially for their aromatic and antibacterial properties. Nowadays, EOs are exploited in the food sector mainly for their aromatic properties. Thanks to their antimicrobial activity, however, they could also be used as additives to increase the safety and the shelf-life of food products. Aim of this study was to assess the antimicrobial activity of Thymus vulgaris L. oil and of Origanum vulgare L. oil against Staphylococcus aureus both in vitro and on fresh cheese, and to determine whether the use of EOs can modify the microbiological and/or chemical-physical properties of the products. The antimicrobial activity against S. aureus in vitro was assessed by preparation of the aromatogram (diffusion in agar test, minimum inhibitory concentration test and minimum bactericidal concentration assessment. Raw sheep milk was experimentally contaminated with a strain of S. aureus ATCC 25922 and was used to produce three types of fresh cheese: without EOs, with thyme and oregano EOs (both EOs at a concentration of 1:1000. The samples were analysed on the day of production, after three and seven days. The results obtained from the tests showed that the concentration of S. aureus and the counts of lactic flora remained unchanged for all types of cheese. Even the chemical-physical parameters were constant. The results of inhibition tests on the cheese disagree with those relating to the in vitro tests. Most likely this is due to the ability of EOs to disperse in the lipids the food: the higher the fat content is, the lower the oil fraction will be able to exert the antimicrobial activity.

  8. Antimicrobial Activity of Essential Oils Against Staphylococcus aureus in Fresh Sheep Cheese.

    Science.gov (United States)

    Amatiste, Simonetta; Sagrafoli, Daniele; Giacinti, Giuseppina; Rosa, Giulia; Carfora, Virginia; Marri, Nicla; Tammaro, Andreana; Bovi, Emanuela; Rosati, Remo

    2014-08-28

    Essential oils (EOs) are aromatic oily liquids extracted from different parts of specific plants, well known especially for their aromatic and antibacterial properties. Nowadays, EOs are exploited in the food sector mainly for their aromatic properties. Thanks to their antimicrobial activity, however, they could also be used as additives to increase the safety and the shelf-life of food products. Aim of this study was to assess the antimicrobial activity of Thymus vulgaris L. oil and of Origanum vulgare L. oil against Staphylococcus aureus both in vitro and on fresh cheese, and to determine whether the use of EOs can modify the microbiological and/or chemical-physical properties of the products. The antimicrobial activity against S. aureus in vitro was assessed by preparation of the aromatogram (diffusion in agar test), minimum inhibitory concentration test and minimum bactericidal concentration assessment. Raw sheep milk was experimentally contaminated with a strain of S. aureus ATCC 25922 and was used to produce three types of fresh cheese: without EOs, with thyme and oregano EOs (both EOs at a concentration of 1:1000). The samples were analysed on the day of production, after three and seven days. The results obtained from the tests showed that the concentration of S. aureus and the counts of lactic flora remained unchanged for all types of cheese. Even the chemical-physical parameters were constant. The results of inhibition tests on the cheese disagree with those relating to the in vitro tests. Most likely this is due to the ability of EOs to disperse in the lipids the food: the higher the fat content is, the lower the oil fraction will be able to exert the antimicrobial activity.

  9. Prion-Specific Antibodies Produced in Wild-Type Mice

    DEFF Research Database (Denmark)

    Heegaard, Peter M. H.; Bergström, Ann-Louise; Andersen, Heidi Gertz

    2015-01-01

    Peptide-specific antibodies produced against synthetic peptides are of high value in probing protein structure and function, especially when working with challenging proteins, including not readily available, non-immunogenic, toxic, and/or pathogenic proteins. Here, we present a straightforward...... method for production of mouse monoclonal antibodies (MAbs) against peptides representing two sites of interest in the bovine prion protein (boPrP), the causative agent of bovine spongiform encephalopathy ("mad cow disease") and new variant Creutzfeldt-Jakob's disease (CJD) in humans, as well......-peptide antibodies, even against peptides very homologous to murine protein sequences. In general, using the strategies described here for selecting, synthesizing, and conjugating peptides and immunizing 4-5 mice with 2-3 different peptides, high-titered antibodies reacting with the target protein are routinely...

  10. Large volume axionic Swiss cheese inflation

    Science.gov (United States)

    Misra, Aalok; Shukla, Pramod

    2008-09-01

    Continuing with the ideas of (Section 4 of) [A. Misra, P. Shukla, Moduli stabilization, large-volume dS minimum without anti-D3-branes, (non-)supersymmetric black hole attractors and two-parameter Swiss cheese Calabi Yau's, arXiv: 0707.0105 [hep-th], Nucl. Phys. B, in press], after inclusion of perturbative and non-perturbative α corrections to the Kähler potential and (D1- and D3-) instanton generated superpotential, we show the possibility of slow roll axionic inflation in the large volume limit of Swiss cheese Calabi Yau orientifold compactifications of type IIB string theory. We also include one- and two-loop corrections to the Kähler potential but find the same to be subdominant to the (perturbative and non-perturbative) α corrections. The NS NS axions provide a flat direction for slow roll inflation to proceed from a saddle point to the nearest dS minimum.

  11. Large volume axionic Swiss cheese inflation

    International Nuclear Information System (INIS)

    Misra, Aalok; Shukla, Pramod

    2008-01-01

    Continuing with the ideas of (Section 4 of) [A. Misra, P. Shukla, Moduli stabilization, large-volume dS minimum without anti-D3-branes, (non-)supersymmetric black hole attractors and two-parameter Swiss cheese Calabi-Yau's, (arXiv: 0707.0105 [hep-th]), Nucl. Phys. B, in press], after inclusion of perturbative and non-perturbative α ' corrections to the Kaehler potential and (D1- and D3-) instanton generated superpotential, we show the possibility of slow roll axionic inflation in the large volume limit of Swiss cheese Calabi-Yau orientifold compactifications of type IIB string theory. We also include one- and two-loop corrections to the Kaehler potential but find the same to be subdominant to the (perturbative and non-perturbative) α ' corrections. The NS-NS axions provide a flat direction for slow roll inflation to proceed from a saddle point to the nearest dS minimum

  12. 21 CFR 133.127 - Cook cheese, koch kaese.

    Science.gov (United States)

    2010-04-01

    ... Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... other procedure which produces a finished cheese having the same physical and chemical properties. The... the action of a lactic acid-producing bacterial culture. One or more of the clotting enzymes specified...

  13. 21 CFR 133.160 - Muenster and munster cheese.

    Science.gov (United States)

    2010-04-01

    ....160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... any other procedure which produces a finished cheese having the same physical and chemical properties... lactic acid-producing bacterial culture. One or more of the clotting enzymes specified in paragraph (b)(2...

  14. 21 CFR 133.144 - Granular and stirred curd cheese.

    Science.gov (United States)

    2010-04-01

    ... 133.144 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... this section or by any other procedure which produces a finished cheese having the same physical and... hydrogen peroxide/catalase, and is subjected to the action of a lactic acid-producing bacterial culture...

  15. Microbiological quality of soft, semi-hard and hard cheeses during the shelf-life

    Directory of Open Access Journals (Sweden)

    Josip Vrdoljak

    2016-03-01

    Full Text Available Cheeses as ready-to-eat food should be considered as a potential source of foodborne pathogens, primarily Listeria monocytogenes. The aim of present study was to determine the microbiological quality of soft, semi-hard and hard cheeses during the shelf-life, with particular reference to L. monocytogenes. Five types of cheeses were sampled at different timepoints during the cold storage and analyzed for presence of Salmonella and L. monocytogenes, as well as lactic acid bacteria, Escherichia coli, coagulase-positive staphylococci, yeasts, molds, sulfite-reducing clostridia and L. monocytogenes counts. Water activity, pH and NaCl content were monitored in order to evaluate the possibility of L. monocytogenes growth. Challenge test for L. monocytogenes was performed in soft whey cheese, to determine the growth potential of pathogen during the shelf-life of product. All analyzed cheeses were compliant with microbiological criteria during the shelf-life. In soft cheeses, lactic acid bacteria increased in the course of the shelf-life period (1.2-2.6 log increase, while in semi-hard and hard cheeses it decreased (1.6 and 5.2 log decrease, respectively. Soft cheeses support the growth of L. monocytogenes according to determined pH values (5.8-6.5, water activity (0.99-0.94, and NaCl content (0.3-1.2%. Challenge test showed that L. monocytogenes growth potential in selected soft cheese was 0.43 log10 cfu/g during 8 days at 4°C. Water activity in semi-hard and hard cheeses was a limiting factor for Listeria growth during the shelf-life. Soft, semi-hard and hard cheeses were microbiologically stable during their defined shelf-life. Good manufacturing and hygienic practices must be strictly followed in the production of soft cheeses as Listeria-supporting food and be focused on preventing (recontamination.

  16. Effect of curd washing on the properties of reduced-calcium and standard-calcium Cheddar cheese.

    Science.gov (United States)

    Hou, Jia; McSweeney, Paul L H; Beresford, Thomas P; Guinee, Timothy P

    2014-10-01

    Washed (W) and nonwashed (NW) variants of standard (SCa) and reduced-calcium (RCa) Cheddar cheeses were made in triplicate, ripened for a 270-d period, and analyzed for composition and changes during maturation. Curd washing was applied to cheeses to give a target level of lactose plus lactic acid in cheese moisture of 3.9 g/100 g in the W cheese, compared with a value of 5.3 g/100 g of lactose plus lactic acid in cheese moisture in the control NW cheeses. The 4 cheese types were denoted standard calcium nonwashed (SCaNW), standard calcium washed (SCaW), reduced-calcium nonwashed (RCaNW), and reduced-calcium washed (RCaW). The mean calcium level was 760 mg/100 g in the SCaNW and SCaW and 660 mg/100 g in the RCaNW and RCaW cheeses. Otherwise the gross composition of all cheeses was similar, each with protein, fat, and moisture levels of ~26, 32, and 36 g/100 g, respectively. Curd washing significantly reduced the mean level of lactic acid in the SCaW cheese and residual lactose in both SCaW and RCaW cheeses. The mean pH of the standard-calcium cheese over the 270-d ripening period increased significantly with curd washing and ripening time, in contrast to the reduced-calcium cheese, which was not affected by the latter parameters. Otherwise curd washing had little effect on changes in populations of starter bacteria or nonstarter lactic acid bacteria, proteolysis, rheology, or color of the cheese during ripening. Descriptive sensory analysis at 270 d indicated that the SCaW cheese had a nuttier, sweeter, less fruity, and less rancid taste than the corresponding SCaNW cheese. In contrast, curd washing was not as effective in discriminating between the RCaW and RCaNW cheeses. The RCaW cheese had a more buttery, caramel odor and flavor, and a more bitter, less sweet, and nutty taste than the SCaW cheese, whereas the RCaNW had a more pungent and less fruity flavor, a less fruity odor, a saltier, more-bitter, and less acidic taste, and a more astringent mouthfeel than

  17. Characterization of a Panela cheese with added probiotics and fava bean starch

    Science.gov (United States)

    Twenty Lactobacillus spp. and eight Bifidobacterium spp. were screened for their ability to ferment fava bean starch. B. breve ATCC 15700 and L. rhamnosus GG ATCC 53103 were selected as probiotics for use in fresh style Panela cheese. Two types of fresh cheese (with and without 3% fava bean starch) ...

  18. Consumer preferences for mild cheddar cheese flavors.

    Science.gov (United States)

    Drake, S L; Gerard, P D; Drake, M A

    2008-11-01

    Flavor is an important factor in consumer selection of cheeses. Mild Cheddar cheese is the classification used to describe Cheddar cheese that is not aged extensively and has a "mild" flavor. However, there is no legal definition or age limit for Cheddar cheese to be labeled mild, medium, or sharp, nor are the flavor profiles or flavor expectations of these cheeses specifically defined. The objectives of this study were to document the distinct flavor profiles among commercially labeled mild Cheddar cheeses, and to characterize if consumer preferences existed for specific mild Cheddar cheese flavors or flavor profiles. Flavor descriptive sensory profiles of a representative array of commercial Cheddar cheeses labeled as mild (n= 22) were determined using a trained sensory panel and an established cheese flavor sensory language. Nine representative Cheddar cheeses were selected for consumer testing. Consumers (n= 215) assessed the cheeses for overall liking and other consumer liking attributes. Internal preference mapping, cluster analysis, and discriminant analysis were conducted. Mild Cheddar cheeses were diverse in flavor with many displaying flavors typically associated with more age. Four distinct consumer clusters were identified. The key drivers of liking for mild Cheddar cheese were: color, cooked/milky, whey and brothy flavors, and sour taste. Consumers have distinct flavor and color preferences for mild Cheddar cheese. These results can help manufacturers understand consumer preferences for mild Cheddar cheese.

  19. Recovering traditional raw-milk Tetilla cheese flavour and sensory attributes by using Kocuria varians and Yarrowia lipolytica adjunct cultures.

    Science.gov (United States)

    Centeno, J A; Garabal, J I; Docampo, F; Lorenzo, J M; Carballo, J

    2017-06-19

    The rationale of the present study was to evaluate the potential of microbial adjunct cultures including Kocuria varians and/or Yarrowia lipolytica strains in the recovery of the typical sensory profile of traditional (raw-milk) Tetilla cheese. Four batches of Tetilla cheese, a short ripened cows' milk cheese produced in Galicia (NW Spain), were made in duplicate from pasteurized milk inoculated with different microbial cultures. A control batch was manufactured by adding a mesophilic commercial D-starter only. The other three batches were made with the same starter after a cheese-milk pre-ripening step carried out with (i) an adjunct culture of K. varians, (ii) an adjunct culture of Y. lipolytica, or (iii) a combination of both adjunct cultures. The highest pH and water activity values, associated with softer textures were determined in the cheeses manufactured with the Y. lipolytica adjunct after 21days of ripening. The contents of the volatile compounds 3-methylbutanol, dimethyl disulfide and dimethyl trisulfide were higher in the cheeses made with only the K. varians adjunct than in the cheeses made with the only yeast adjunct and in the control cheeses. The contents of hexanoic and octanoic acids were highest in the cheeses made with the Y. lipolytica adjunct, and levels of ethyl hexanoate, ethyl octanoate and ethyl decanoate were higher in the cheeses made with only the yeast adjunct than in the other batches of cheese. The cheeses manufactured with both adjunct cultures were awarded the highest scores for flavour and overall sensory parameters (considering the standards of the traditional product) and were considered very similar to 'good quality' artisanal raw-milk cheeses. We conclude that use of selected Micrococcaceae and Y. lipolytica strains as adjunct cultures would differentiate the sensory properties and contribute to the quality and typicality of the short-ripened rennet-curd Galician Tetilla and Arzúa-Ulloa cheeses. Copyright © 2017 Elsevier B

  20. Traditional Cheese Production and an EU Labeling Scheme: The Alpine Cheese Producers’ Opinion

    Directory of Open Access Journals (Sweden)

    Alessandro Bonadonna

    2017-08-01

    Full Text Available In 2012, the European Union introduced two optional quality terms (OQT as new tools for the enhancement of food products. Two years later, the requirements for the use of the OQT “mountain product” were defined to enhance agricultural production in harsh environments, such as mountain areas. This new tool aimed at promoting local development, maintaining the economic activities in mountain areas and redistributing wealth. The present research aims at understanding if farmers perceived this tool as useful and evaluates their level of awareness. To this aim, a sample of 68 traditional cheese producers from the North West Alpine Arch was interviewed. The results show that some cheese producers have a positive attitude towards the concepts set out in the OQT “mountain product” and consider it a useful tool to promote and enhance their products. Some critical elements are also discussed.

  1. Transfer of Orally Administered Terpenes in Goat Milk and Cheese

    Directory of Open Access Journals (Sweden)

    I. Poulopoulou

    2012-10-01

    Full Text Available The objective of the present study was to investigate the relationships between terpenes’ intake and their presence in animal tissues (blood and milk as well as in the final product (cheese. Eight dairy goats were divided in two balanced groups, representing control (C and treatment (T group. In T group oral administration of a mixture of terpenes (α-pinene, limonene and β-caryophyllene was applied over a period of 18 d. Cheese was produced, from C and T groups separately, on three time points, twice during the period of terpenes’ oral administration and once after the end of experiment. Terpenes were identified in blood by extraction using petroleum ether and in milk and cheese by the use of solid phase micro-extraction (SPME method, followed by GC-MS analysis. Chemical properties of the milk and the produced cheeses were analyzed and found not differing between the two groups. Limonene and α-pinene were found in all blood and milk samples of the T group after a lag-phase of 3 d, while β-caryophyllene was determined only in few milk samples. Moreover, none of the terpenes were traced in blood and milk of C animals. In cheese, terpenes’ concentrations presented a more complicated pattern implying that terpenes may not be reliable feed tracers. We concluded that monoterpenes can be regarded as potential feed tracers for authentification of goat milk, but further research is required on factors affecting their transfer.

  2. Sex in Cheese: Evidence for Sexuality in the Fungus Penicillium roqueforti

    Science.gov (United States)

    Ropars, Jeanne; Dupont, Joëlle; Fontanillas, Eric; Rodríguez de la Vega, Ricardo C.; Malagnac, Fabienne; Coton, Monika; Giraud, Tatiana; López-Villavicencio, Manuela

    2012-01-01

    Although most eukaryotes reproduce sexually at some moment of their life cycle, as much as a fifth of fungal species were thought to reproduce exclusively asexually. Nevertheless, recent studies have revealed the occurrence of sex in some of these supposedly asexual species. For industrially relevant fungi, for which inoculums are produced by clonal-subcultures since decades, the potentiality for sex is of great interest for strain improvement strategies. Here, we investigated the sexual capability of the fungus Penicillium roqueforti, used as starter for blue cheese production. We present indirect evidence suggesting that recombination could be occurring in this species. The screening of a large sample of strains isolated from diverse substrates throughout the world revealed the existence of individuals of both mating types, even in the very same cheese. The MAT genes, involved in fungal sexual compatibility, appeared to evolve under purifying selection, suggesting that they are still functional. The examination of the recently sequenced genome of the FM 164 cheese strain enabled the identification of the most important genes known to be involved in meiosis, which were found to be highly conserved. Linkage disequilibria were not significant among three of the six marker pairs and 11 out of the 16 possible allelic combinations were found in the dataset. Finally, the detection of signatures of repeat induced point mutations (RIP) in repeated sequences and transposable elements reinforces the conclusion that P. roqueforti underwent more or less recent sex events. In this species of high industrial importance, the induction of a sexual cycle would open the possibility of generating new genotypes that would be extremely useful to diversify cheese products. PMID:23185400

  3. Virulence factors and genetic variability of Staphylococcus aureus strains isolated from raw sheep's milk cheese.

    Science.gov (United States)

    Spanu, Vincenzo; Spanu, Carlo; Virdis, Salvatore; Cossu, Francesca; Scarano, Christian; De Santis, Enrico Pietro Luigi

    2012-02-01

    Contamination of dairy products with Staphylococcus aureus can be of animal or human origin. The host pathogen relationship is an important factor determining genetic polymorphism of the strains and their potential virulence. The aim of the present study was to carry out an extensive characterization of virulence factors and to study the genetic variability of S. aureus strains isolated from raw ewe's milk cheese. A total of 100 S. aureus strains isolated from cheese samples produced in 10 artisan cheese factories were analyzed for the presence of enterotoxins (sea-see) and enterotoxins-like genes (seh, sek, sel, sem, seo, sep), leukocidins, exfoliatins, haemolysins, toxic shock syndrome toxin 1 (TSST-1) and the accessory gene regulator alleles (agr). Strains were also typed using pulsed-field gel electrophoresis (PFGE). AMOVA analysis carried out on PFGE and PCR data showed that the major component explaining genetic distance between strains was the dairy of origin. Of the total isolates 81% had a pathogenicity profile ascribable to "animal" biovar while 16% could be related to "human" biovar. The biovar allowed to estimate the most likely origin of the contamination. Minimum inhibitory concentrations (MICs) of nine antimicrobial agents and the presence of the corresponding genes coding for antibiotic resistance was also investigated. 18 strains carrying blaZ gene showed resistance to ampicillin and penicillin and 6 strains carrying tetM gene were resistant to tetracycline. The presence of mecA gene and methicillin resistance, typical of strains of human origin, was never detected. The results obtained in the present study confirm that S. aureus contamination in artisan cheese production is mainly of animal origin. Copyright © 2011. Published by Elsevier B.V.

  4. Production and characterisation of reduced-fat and PUFA-enriched Burrata cheese.

    Science.gov (United States)

    Trani, Antonio; Gambacorta, Giuseppe; Gomes, Tommaso F; Loizzo, Pasqua; Cassone, Angela; Faccia, Michele

    2016-05-01

    Burrata is an Italian fresh 'pasta filata' cheese made from cow's milk and cream that is rapidly spreading in Europe. It has very high caloric content, and a technological protocol was developed for producing a reduced-fat type and fortifying it with polyunsaturated fatty acids (PUFA) of vegetable origin. A satisfactory reduced-fat prototype was obtained by using a 14% fat cream, which was specifically developed by diluting double cream with a suspension of carob seed flour. The composition of the new cheese changed with respect to the control, but the sensory characteristics were not impaired. Moisture increased from 62·6 to 68·4%, fat on dry matter decreased from 59·1 to 34·7%, and the caloric content decreased from 1060·8 to 718 J/100 g. Proteolysis and lipolysis were not affected by the technological modifications: after 7 d storage, the electrophoretic pattern of caseins and the free fatty acids profile of experimental and control cheeses were not significantly different. Fortification of reduced-fat Burrata with PUFA was obtained by using two commercial formulates available at a compatible price with the current economic values of the cheese. The two formulates derived from flaxseeds and Carthamus tinctorius oil and allowed enrichment in C18 :3 : n3 (α-linolenic acid, ALA), and 9cis,11trans- and 10trans,12cis- conjugated linoleic acid (CLA), respectively. Fortification was easy to perform under a technical point of view, but the negative sensory impact limited fortification at a maximum of 7·0 mg g-1 fat ALA and 6·8 g-1 fat CLA.

  5. Influence of calcium and phosphorus, lactose, and salt-to-moisture ratio on Cheddar cheese quality: changes in residual sugars and water-soluble organic acids during ripening.

    Science.gov (United States)

    Upreti, P; McKay, L L; Metzger, L E

    2006-02-01

    Cheddar cheese ripening involves the conversion of lactose to glucose and galactose or galactose-6-phosphate by starter and nonstarter lactic acid bacteria. Under ideal conditions (i.e., where bacteria grow under no stress of pH, water activity, and salt), these sugars are mainly converted to lactic acid. However, during ripening of cheese, survival and growth of bacteria occurs under the stressed condition of low pH, low water activity, and high salt content. This forces bacteria to use alternate biochemical pathways resulting in production of other organic acids. The objective of this study was to determine if the level and type of organic acids produced during ripening was influenced by calcium (Ca) and phosphorus (P), residual lactose, and salt-to-moisture ratio (S/M) of cheese. Eight cheeses with 2 levels of Ca and P (0.67 and 0.47% vs. 0.53 and 0.39%, respectively), lactose at pressing (2.4 vs. 0.78%), and S/M (6.4 vs. 4.8%) were manufactured. The cheeses were analyzed for organic acids (citric, orotic, pyruvic, lactic, formic, uric, acetic, propanoic, and butyric acids) and residual sugars (lactose, galactose) during 48 wk of ripening using an HPLC-based method. Different factors influenced changes in concentration of residual sugars and organic acids during ripening and are discussed in detail. Our results indicated that the largest decrease in lactose and the largest increase in lactic acid occurred between salting and d 1 of ripening. It was interesting to observe that although the lactose content in cheese was influenced by several factors (Ca and P, residual lactose, and S/M), the concentration of lactic acid was influenced only by S/M. More lactic acid was produced in low S/M treatments compared with high S/M treatments. Although surprising for Cheddar cheese, a substantial amount (0.2 to 0.4%) of galactose was observed throughout ripening in all treatments. Minor changes in the levels of citric, uric, butyric, and propanoic acids were observed during

  6. Variability of Bacterial Biofilms of the “Tina” Wood Vats Used in the Ragusano Cheese-Making Process▿

    OpenAIRE

    Licitra, G.; Ogier, J. C.; Parayre, S.; Pediliggieri, C.; Carnemolla, T. M.; Falentin, H.; Madec, M. N.; Carpino, S.; Lortal, S.

    2007-01-01

    Ragusano cheese is a “protected denomination of origin” cheese made in the Hyblean region of Sicily from raw milk using traditional wooden tools, without starter. To explore the Ragusano bacterial ecosystem, molecular fingerprinting was conducted at different times during the ripening and biofilms from the wooden vats called “tinas” were investigated. Raw milks collected at two farm sites, one on the mountain and one at sea level, were processed to produce Ragusano cheese. Raw milk, curd befo...

  7. Identification of the risk factors associated with cheese production to implement the hazard analysis and critical control points (HACCP) system on cheese farms.

    Science.gov (United States)

    Carrascosa, Conrado; Millán, Rafael; Saavedra, Pedro; Jaber, José Raduán; Raposo, António; Sanjuán, Esther

    2016-04-01

    The purpose of this paper was to evaluate, by statistical analyses, risk factors on cheese farms that can influence the microbial contamination of their products. Various assessment tools, such as cheese production questionnaires, food handlers' knowledge testing, and hygiene assessment system surveys, were used on 39 cheese farms on the island of Gran Canaria, Spain. The microbiological status of 773 raw milk and cheese samples from the cheese farms was assessed by enumerating total viable counts and 4 pathogens: Escherichia coli, Staphylococcus aureus, Listeria monocytogenes, and Salmonella spp. The results revealed that the highest contamination by Staph. aureus (4.39%, >10(5)cfu/mL) was found in milk, and the highest contamination by E. coli (5.18%, >10(3) cfu/mL) was found in cheese. Very few samples (0.52%) were contaminated by L. monocytogenes or Salmonella spp. The factors associated with any tested microorganism were "handling," "knowledge," and "type of milk." Subsequently, multidimensional logistic analysis for contamination by E. coli showed an independent association for factors "cleaning and disinfection test" and "type of milk." The probability of total aerobic contamination of milk increased with lower hygiene assessment system survey scores. These results emphasize the need to apply and maintain good hygiene practices, and to study risk factors to prevent contamination and bacterial growth. Further research is required in other areas with different cheese farm types to reinforce the validity of these results. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Complexity and Uniqueness of the Aromatic Profile of Smoked and Unsmoked Herreño Cheese

    Directory of Open Access Journals (Sweden)

    Gemma Palencia

    2014-06-01

    Full Text Available In this work, the volatile fraction of unsmoked and smoked Herreño cheese, a type of soft cheese from the Canary Islands, has been characterized for the first time. In order to evaluate if the position in the smokehouse could influence the volatile profile of the smoked variety, cheeses smoked at two different heights were studied. The volatile components were extracted by Solid Phase Microextraction using a divinylbenzene/carboxen/ polydimethylsiloxane fiber, followed by Gas Chromatography/Mass Spectrometry. In total, 228 components were detected. The most numerous groups of components in the unsmoked Herreño cheese were hydrocarbons, followed by terpenes and sesquiterpenes, whereas acids and ketones were the most abundant. It is worth noticing the high number of aldehydes and ketones, and the low number of alcohols and esters in this cheese in relation to others, as well as the presence of some specific unsaturated hydrocarbons, terpenes, sesquiterpenes and nitrogenated derivatives. The smoking process enriches the volatile profile of Herreño cheese with ketones and diketones, methyl esters, aliphatic and aromatic aldehydes, hydrocarbons, terpenes, nitrogenated compounds, and especially with ethers and phenolic derivatives. Among these, methylindanones or certain terpenes like α-terpinolene, have not been detected previously in other types of smoked cheese. Lastly, the results obtained suggest a slightly higher smoking degree in the cheeses smoked at a greater height.

  9. Microbiota of an unpasteurised cellar-stored goat cheese from northern Sweden

    Directory of Open Access Journals (Sweden)

    Klara Båth

    2012-06-01

    Full Text Available This qualitative study reports on lactic acid bacteria (LAB, yeasts and moulds isolated from three artisanal Swedish cellar-stored goat cheeses aged for 1, 3 and 5 months. Starter culture LAB dominated in the younger cheeses, and Leuconostoc pseudomesenteroides, common in raw goats’ milk, had persisted from the unpasteurised milk into all the cheeses. Non-starter LAB dominated in the 5 month cheese, in particular, Lactobacillus sakei, a meat-associated LAB not previously isolated from cheese. Debaryomyces hansenii, and Penicillium and Mucor species were dominant among the yeasts and moulds, respectively. The cheese rind was not formed primarily from Penicillium species as in traditional cheeses such as Camembert – rather, mycelium from Mucor mucedo contributed to rind formation. Mould species known to produce sterigmatocystin, aflatoxins or ochratoxin A in cheese were not isolated in this study; growth of mycotoxigenic Aspergilli may have been inhibited by the cool conditions in the earth-cellar (4–6 °C.

  10. Survival of bioluminescent Listeria monocytogenes and Escherichia coli O157:H7 in soft cheeses.

    Science.gov (United States)

    Ramsaran, H; Chen, J; Brunke, B; Hill, A; Griffiths, M W

    1998-07-01

    Pasteurized and raw milks that had been inoculated at 10(4) cfu/ml with bioluminescent strains of Listeria monocytogenes and Escherichia coli O157:H7 were used in the manufacture of Camembert and Feta cheeses with or without nisin-producing starter culture. Survival of both organisms was determined during the manufacture and storage of Camembert and Feta cheeses at 2 +/- 1 degree C for 65 and 75 d, respectively. Bacterial bioluminescence was used as an indicator to enumerate the colonies plated on selective Listeria agar and on MacConkey agar. Escherichia coli O157:H7 survived the manufacturing process of both cheeses and was present at the end of the storage period in greater numbers than in the initial inoculum. At the end of 75 d of storage, E. coli O157:H7 was found in the brine of Feta cheese. The counts of L. monocytogenes increased as the pH of the Camembert cheese increased, and there were significant differences between the counts from samples taken from the inside and the counts from samples obtained near the surface of the cheese. The Feta cheese that contained nisin was the only cheese in which L. monocytogenes was at the level of the initial inoculum after 75 d of storage.

  11. MINERAL COMPONENTS OF BLOOD SERUM AND QUALITY PARAMETERS OF MILK AND CHEESE OF SHEEP

    Directory of Open Access Journals (Sweden)

    Amina Hrković-Porobija

    2013-02-01

    Full Text Available Plan of research included two Pramenka sheep-breeding family farms producing Livno and Travnik cheese in the traditional ways. The experiment included 117 animals of the Pramenka strain. The serum concentrations of the minerals (calcium, phosphorus and magnesium were followed over time. Based on the physical-chemical analysis of the sheep milk, we evaluated the milk parameters (milk fat, protein and lactose and cheese parameters (dry matter, moisture, grease and pH that can be indicative of the cheese milk quality. The aim of the study was to determine the effect of the serum minerals to the sheep milk quality, and the Livno and Travnik cheese quality, being the final products. Blood, milk and cheese samples were taken in the summer during the summer grazing of sheep. The results were analyzed using the software package/Program SPSS 15.00. Differences were considered statistically significant at p <0.05. Influence of serum minerals on the quality of milk and cheese was determined by calculating the correlation factor.Analysis of mineral blood components and basic milkand cheese parameters showed variations, wich may be acceptable considering the influence of lactation, climate and botanic quality.Keywords: sheep, mineral components of serum, milk, cheese, correlation

  12. Influence of starter culture on total free aminoacids concentration during ripening of Krk cheese

    Directory of Open Access Journals (Sweden)

    Biljana Radeljević

    2013-03-01

    Full Text Available The aim of this study was to determine the influence of microbial (commercial starter culture on concentration of total free amino groups (amino acids in cheeses in different ripening stages. Free amino groups were determined by reaction with ninhydrin with cadmium (Cd in the water soluble cheese extract, and were expressed as the concentration of leucine in cheese dry matter. Changes in concentration of total free amino acids during cheese ripening (0th, 30th, 60th, 90th and 120th day were monitored. In water soluble extracts of cheese, the presence of free NH2 groups in all ripening stages was detected, which means smaller peptides and amino acids, whose concentration significantly (P<0.01 increased during ripening. Cheeses produced with and without microbial culture resulted in statistically significant differences (P<0.01 in content amino acids free on the 90th and 120th day of ripening. Cd - ninhydrin method was found to be suitable for cheese ripening monitoring, as well as for determination of the differences in mature characteristics of cheeses, depending on the production process.

  13. Characterization of volatiles in Beaten cheeses (bieno sirenje by SPME/GC-MC: Influence of geographical origin

    Directory of Open Access Journals (Sweden)

    Sulejmani Erhan

    2014-01-01

    Full Text Available In this study, the volatile profiles of a type of economically important cheeses for the FYR Macedonian dairy sector were characterized. A total of eighteen samples belonged to 6 different geographical regions of Beaten cheese, including cheeses from Kumanovo, Tetovo, Struga, Resen, Veles and Radovish were comparatively studied for their volatile profiles. Sixty two volatile compounds were identified in the cheeses by solid-phase microextraction combined with gas chromatography-mass spectrometry and the results are discussed based on their chemical classes (18 esters, 13 ketones, 10 acids, 8 alcohols, 5 terpenes, and 8 miscellaneous compounds. Acids, esters and alcohols were the most abundant classes identified and were highly dependent on the geographical origin of cheeses. Beaten cheese from Struga had the highest levels of carboxylic acids, ketones, alcohols, esters and terpenes. The Beaten cheese from other geographical origin had low levels of volatiles probably from the effect of variable characteristics of used milk and different cheese making process which affects the biochemical processes. The results suggest that each cheese from different geographical regions had different volatiles profile and the manufacturing technique as well as the ripening stage of the cheeses played a major role on the volatile compounds’ distribution.

  14. 21 CFR 133.111 - Caciocavallo siciliano cheese.

    Science.gov (United States)

    2010-04-01

    ... properties as the cheese produced when the procedure set forth in paragraph (b) of this section is used. It... purified calcium chloride in a quantity not more than 0.02 percent, calculated as anhydrous calcium... of benzoyl peroxide with potassium alum, calcium sulfate, and magnesium carbonate; but the weight of...

  15. Interactions between yeasts and bacteria in the smear surface-ripened cheeses.

    Science.gov (United States)

    Corsetti, A; Rossi, J; Gobbetti, M

    2001-09-19

    In the initial phase of ripening, the microflora of bacterial smear surface-ripened cheeses such as Limburger, Taleggio, Brick, Münster and Saint-Paulin and that of surface mould-ripened cheeses such as Camembert and Brie may be similar, but at the end of the ripening, bacteria such as Brevibacterium spp., Arthrobacter spp., Micrococcus spp., Corynebacterium spp. and moulds such as Penicillium camemberti are, respectively, the dominant microorganisms. Yeasts such as Candida spp., Cryptococcus spp., Debaryomyces spp., Geotrichum candidum, Pichia spp., Rhodotorula spp., Saccharomyces spp. and Yarrowia lipolytica are often and variably isolated from the smear surface-ripened cheeses. Although not dominant within the microorganisms of the smear surface-ripened cheeses, yeasts establish significant interactions with moulds and especially bacteria, including surface bacteria and lactic acid bacteria. Some aspects of the interactions between yeasts and bacteria in such type of cheeses are considered in this paper.

  16. Real Deal or No Deal? A Comparative Analysis of Raw Milk Cheese Regulation in Australia and France

    Directory of Open Access Journals (Sweden)

    William van Caenegem

    2017-04-01

    cheeses, the new standard is rigid and does not encourage new entrants into the emerging raw milk cheese consumer market. This article compares the Australian system with the French raw milk cheese regulation and production system, and argues that its approach in encouraging and supporting small farmhouse artisanal traditional raw milk cheese is beneficial to both producer and consumer, and has not resulted in any significant health risks. The Australian approach amounts to a missed opportunity to encourage the emergence of a value-added industry with local and export potential, and is at odds with important movements in food policy, such as recognition of the value of localism and terroir.

  17. Screening and selection of Lactobacillus strains for use as adjunct cultures in production of semi-hard cheese.

    Science.gov (United States)

    Antonsson, Martin; Ardö, Ylva; Nilsson, Bengt Frans; Molin, Göran

    2002-08-01

    Thirty-three Lactobacillus strains were tested as adjuncts in a cheese model system. Eighteen strains originated from cheese (nine Lactobacillus spp. and nine Lb. paracasei/casei) and 15 from human intestinal mucosa (11 Lb. rhamnosus; three Lb. paracasei; one Lb. plantarum). Model cheeses weighing 120 g were made of cheese grains from full-scale production of washed curd semi-hard cheese (Herrgård). The model system was reproducible and similar to full-scale production with respect to moisture, salt content, pH and microbial flora. The model cheeses were sampled for aerobic and anaerobic plate count and viable counts of Lactobacillus and Lactococcus. The presence of adjuncts in the model cheeses was confirmed by typing isolates with Randomly Amplified Polymorphic DNA (RAPD). The sensory properties of model cheeses were described. In a first trial 23 of the 33 adjuncts were re-isolated from the corresponding model cheeses after 9 or 13 weeks. Adjuncts of Lb. paracasei were re-isolated more frequently than adjuncts of Lb. rhamnosus. Nine strains were selected, on the basis of their ability to grow and be a dominating part of the microflora of model cheese with interesting sensory properties. These strains were further studied together with two commercial cultures. The sensory influences on model cheeses of six of the adjuncts were confirmed, and flavour scores were in the range of 2.9-7.1 for model cheeses with different adjuncts while the control had a flavour score of 5.6 (0-10 scale). Survival and growth of seven out of the nine strains correlated with the results of the first trial. Growth and influence on flavour of four adjunct cultures were confirmed in experimental cheese manufactured in a 400-1 open vat.

  18. Szekeres Swiss-cheese model and supernova observations

    International Nuclear Information System (INIS)

    Bolejko, Krzysztof; Celerier, Marie-Noeelle

    2010-01-01

    We use different particular classes of axially symmetric Szekeres Swiss-cheese models for the study of the apparent dimming of the supernovae of type Ia. We compare the results with those obtained in the corresponding Lemaitre-Tolman Swiss-cheese models. Although the quantitative picture is different the qualitative results are comparable, i.e., one cannot fully explain the dimming of the supernovae using small-scale (∼50 Mpc) inhomogeneities. To fit successfully the data we need structures of order of 500 Mpc size or larger. However, this result might be an artifact due to the use of axial light rays in axially symmetric models. Anyhow, this work is a first step in trying to use Szekeres Swiss-cheese models in cosmology and it will be followed by the study of more physical models with still less symmetry.

  19. Microbiological quality of retail cheeses made from raw, thermized or pasteurized milk in the UK.

    Science.gov (United States)

    Little, C L; Rhoades, J R; Sagoo, S K; Harris, J; Greenwood, M; Mithani, V; Grant, K; McLauchlin, J

    2008-04-01

    Two studies of retail fresh, ripened and semi-hard cheeses made from raw, thermized or pasteurized milk were undertaken in the UK during 2004 and 2005 to determine the microbiological quality of these products. Using microbiological criteria in European Commission Recommendations 2004/24/EC and 2005/175/EC, 2% of both raw, thermized (37/1819 samples) and pasteurized (51/2618 samples) milk cheeses were of unsatisfactory quality. Raw or thermized milk cheeses were of unsatisfactory quality due to levels of Staphylococcus aureus at 10(4)cfu g(-1), Escherichia coli at 10(5)cfu g(-1), and/or Listeria monocytogenes at 10(2)cfu g(-1), whereas pasteurized milk cheeses were of unsatisfactory quality due to S. aureus at 10(3)cfu g(-1) and/or E. coli at 10(3)cfu g(-1). Salmonella was not detected in any samples. Cheeses were of unsatisfactory quality more frequently when sampled from premises rated as having little or no confidence in management and control systems, and stored/displayed at above 8 degrees C. Raw or thermized milk cheeses were also more likely to be of unsatisfactory quality when they were unripened types, and pasteurized milk cheeses when they were: semi-hard types; from specialist cheese shops or delicatessens; cut to order. These results emphasize the need for applying and maintaining good hygiene practices throughout the food chain to prevent contamination and/or bacterial growth. Labelling of cheeses with clear information on whether the cheese was prepared from raw milk also requires improvement.

  20. We tasted a genetically modified cheese - and we like it!

    DEFF Research Database (Denmark)

    Bech-Larsen, Tino; Grunert, Klaus G.; Scholderer, Joachim

    This paper presents the preliminary results of a conjoint study of 750 Danish, Swedish, Norwegian and Finnish consumers´ preferences for genetically modified and conventional cheese with different types of benefits. The results showed homogeneity in preferences within as well as across countries...

  1. Distribution and stability of Aflatoxin M1 during processing and ripening of traditional white pickled cheese.

    Science.gov (United States)

    Oruc, H H; Cibik, R; Yilmaz, E; Kalkanli, O

    2006-02-01

    The distribution of aflatoxin M(1) (AFM(1)) has been studied between curd, whey, cheese and pickle samples of Turkish white pickled cheese produced according to traditional techniques and its stability studied during the ripening period. Cheeses were produced in three cheese-making trials using raw milk that was artificially contaminated with AFM(1) at the levels of 50, 250 and 750 ng/l and allowed to ripen for three months. AFM(1) determinations were carried out at intervals by LC with fluorescence detection after immunoaffinity column clean-up. During the syneresis of the cheese a proportionately high concentration of AFM(1) remained in curd and for each trial the level was 3.6, 3.8 and 4.0 times higher than levels in milk. At the end of the ripening, the distribution of AFM(1) for cheese/whey + brine samples was 0.9, 1.0 and 1.3 for first, second and third spiking respectively indicating that nearly half of the AFM(1) remained in cheese. It has been found that only 2-4% of the initial spiking of AFM(1) transferred into the brine solution. During the ripening period AFM(1) levels remained constant suggesting that AFM(1) was quite stable during manufacturing and ripening.

  2. Debaryomyces hansenii strains differ in their production of flavor compounds in a cheese-surface model

    DEFF Research Database (Denmark)

    Gori, Klaus; Sørensen, Louise Marie; Petersen, Mikael Agerlin

    2012-01-01

    Flavor production among12 strains of Debaryomyces hansenii when grown on a simple cheese model mimicking a cheese surface was investigated by dynamic headspace sampling followed by gas chromatography-mass spectrometry. The present study confirmed that D. hansenii possess the ability to produce...

  3. Preliminary Discrimination of Cheese Adulteration by FT-IR Spectroscopy

    Directory of Open Access Journals (Sweden)

    Lucian Cuibus

    2014-11-01

    Full Text Available The present work describes a preliminary study to compare some traditional Romanian cheeses and adulterated cheeses using Attenuated Total Reflectance-Fourier transform infrared spectroscopy (ATR-FTIR. For PLS model calibration (6 concentration levels and validation (5 concentration levels sets were prepared from commercial Dalia Cheese from different manufacturers by spiking it with palm oil at concentrations ranging 2-50 % and 5-40 %, respectively. Fifteen Dalia Cheese were evaluated as external set. The spectra of each sample, after homogenization, were acquired in triplicate using a FTIR Shimatsu Prestige 21 Spectrophotometer, with a horizontal diamond ATR accessory in the MIR region 4000-600 cm-1. Statistical methods as PLS were applied using MVC1 routines written for Matlab R2010a. As first step the optimal condition for PLS model were obtained using cross-validation on the Calibration set. Spectral region in 3873-652 cm-1, and 3 PLS-factors were stated as the best conditions and showed an R2 value of 0.9338 and a relative error in the calibration of 17.2%. Then validation set was evaluated, obtaining good recovery rates (108% and acceptable dispersion of the data (20%. The curve of actual vs. predicted values shows slope near to 1 and origin close to 0, with an R2 of 0.9695. When the external sample set was evaluated, samples F19, F21, F22 and F24, showed detectable levels of palm fats. The results proved that FTIR-PLS is a reliable non-destructive technique for a rapid quantification the level of adulteration in cheese.  The spectroscopic methods could assist the quality control authority, traders and the producers to discriminate the adulterated cheeses with palm oil.

  4. Antimicrobial properties of lactic acid bacteria isolated from uruguayan artisan cheese

    Directory of Open Access Journals (Sweden)

    Martín Fraga Cotelo

    2013-12-01

    Full Text Available Uruguayan artisan cheese is elaborated with raw milk and non-commercial starters. The associated native microbiota may include lactic acid bacteria and also potentially pathogenic bacteria. Lactic acid bacteria were isolated from artisan cheese, raw milk, and non-commercial starter cultures, and their potential bacteriocin production was assessed. A culture collection of 509 isolates was obtained, and five isolates were bacteriocin-producers and were identified as Enterococcus durans,Lactobacillus casei, and Lactococcus lactis. No evidence of potential virulence factors were found in E. durans strains. These are promising results in terms of using these native strains for cheese manufacture and to obtain safe products.

  5. Texture of low-fat Iranian White cheese as influenced by gum tragacanth as a fat replacer.

    Science.gov (United States)

    Rahimi, J; Khosrowshahi, A; Madadlou, A; Aziznia, S

    2007-09-01

    The effect of different concentrations of gum tragacanth on the textural characteristics of low-fat Iranian White cheese was studied during ripening. A batch of full-fat and 5 batches of low-fat Iranian White cheeses with different gum tragacanth concentrations (without gum or with 0.25, 0.5, 0.75, or 1 g of gum/kg of milk) were produced to study the effects of fat content reduction and gum concentration on the textural and functional properties of the product during ripening. Cheese samples were analyzed with respect to chemical, color, and sensory characteristics, rheological parameters (uniaxial compression and small-amplitude oscillatory shear), and microstructure. Reducing the fat content had an adverse effect on cheese yield, sensory characteristics, and the texture of Iranian White cheese, and it increased the instrumental hardness parameters (i.e., fracture stress, elastic modulus, storage modulus, and complex modulus). However, increasing the gum tragacanth concentration reduced the values of instrumental hardness parameters and increased the whiteness of cheese. Although when the gum concentration was increased, the low-fat cheese somewhat resembled its full-fat counterpart, the interaction of the gum concentration with ripening time caused visible undesirable effects on cheese characteristics by the sixth week of ripening. Cheeses with a high gum tragacanth concentration became very soft and their solid texture declined somewhat.

  6. Efecto de la Adición de dos Tipos de Almidones en las Propiedades Texturales de Queso Análogo / Effect of the Addition of Two Types of Starch in the Textural Properties of Analogue Cheese

    Directory of Open Access Journals (Sweden)

    Jacqueline Agudelo Chaparro

    2014-12-01

    Full Text Available Resumen. Se estudió el efecto que tienen dos tipos de almidónmodificado, maíz ceroso y papa, en las propiedades texturalesde un queso análogo con fibra prebiótica soluble. Se elaboraronquesos semiblandos, con humedad de 48%, reemplazando el10% de proteína por los almidones modificados, dando lugar atres tratamientos: Formulación control (FC, formulación maízceroso (FMC y formulación papa (FP. Se observó que la adiciónde los almidones afecta significativamente (P<0,05 la dureza, laadhesividad, la gomosidad, la elasticidad y la masticabilidad delproducto. /  Abstract. The effect they have two types of modified starch (waxycorn and potato in the textural properties of an analogue cheesewas studied. Semi-soft cheeses were made with 48% moisture,replacing the 10% protein by modified starches, resulting in threetreatments: Control formulation (CF, waxy corn formulation(WCF and potato formulation (PF. The study allowed note thatthe addition of starches significantly affect (P<0.05 the hardness,adhesiveness, gumminess, elasticity and chewiness of the product

  7. Biodiversity and γ-aminobutyric acid production by lactic acid bacteria isolated from traditional alpine raw cow's milk cheeses.

    Science.gov (United States)

    Franciosi, Elena; Carafa, Ilaria; Nardin, Tiziana; Schiavon, Silvia; Poznanski, Elisa; Cavazza, Agostino; Larcher, Roberto; Tuohy, Kieran M

    2015-01-01

    "Nostrano-cheeses" are traditional alpine cheeses made from raw cow's milk in Trentino-Alto Adige, Italy. This study identified lactic acid bacteria (LAB) developing during maturation of "Nostrano-cheeses" and evaluated their potential to produce γ-aminobutyric acid (GABA), an immunologically active compound and neurotransmitter. Cheese samples were collected on six cheese-making days, in three dairy factories located in different areas of Trentino and at different stages of cheese ripening (24 h, 15 days, and 1, 2, 3, 6, and 8 months). A total of 1,059 LAB isolates were screened using Random Amplified Polymorphic DNA-PCR (RAPD-PCR) and differentiated into 583 clusters. LAB strains from dominant clusters (n = 97) were genetically identified to species level by partial 16S rRNA gene sequencing. LAB species most frequently isolated were Lactobacillus paracasei, Streptococcus thermophilus, and Leuconostoc mesenteroides. The 97 dominant clusters were also characterized for their ability in producing GABA by high-performance liquid chromatography (HPLC). About 71% of the dominant bacteria clusters evolving during cheeses ripening were able to produce GABA. Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus. No Enterococcus faecalis or Sc. macedonicus isolates produced GABA. The isolate producing the highest amount of GABA (80.0±2.7 mg/kg) was a Sc. thermophilus.

  8. Application of UHPLC for the determination of free amino acids in different cheese varieties.

    Science.gov (United States)

    Mayer, Helmut K; Fiechter, Gregor

    2013-10-01

    A rapid ultra-high performance liquid chromatography (UHPLC) protocol for the determination of amino acids as their respective 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate (AQC) derivatives was successfully applied for assessing free amino acid levels in commercial cheese samples representing typical product groups (ripening protocols) in cheesemaking. Based on the Waters AccQ.Tag™ method as a high performance liquid chromatography (HPLC) amino acid solution designed for hydrolyzate analyses, method adaptation onto UHPLC was performed, and detection of AQC derivatives was changed from former fluorescence (λ(Ex) 250 nm/λ(Em) 395 nm) to UV (254 nm). Compared to the original HPLC method, UHPLC proved to be superior by facilitating excellent separations of 18 amino acids within 12 min only, thus demonstrating significantly shortened runtimes (>35 min for HPLC) while retaining the original separation chemistry and amino acid elution pattern. Free amino acid levels of the analyzed cheese samples showed a high extent of variability depending on the cheese type, with highest total amounts found for original Italian extra-hard cheeses (up to 9,000 mg/100 g) and lowest for surface mold- or bacterial smear-ripened soft cheeses (200-600 mg/100 g). Despite the intrinsic variability in both total and specific concentrations, the established UHPLC method enabled reliable and interference-free amino acid profiling throughout all cheese types, thus demonstrating a valuable tool to generate high quality data for the characterization of cheese ripening.

  9. Effects of highly ripened cheeses on HL-60 human leukemia cells: antiproliferative activity and induction of apoptotic DNA damage.

    Science.gov (United States)

    Yasuda, S; Ohkura, N; Suzuki, K; Yamasaki, M; Nishiyama, K; Kobayashi, H; Hoshi, Y; Kadooka, Y; Igoshi, K

    2010-04-01

    To establish cheese as a dairy product with health benefits, we examined the multifunctional role of cheeses. In this report, we clarify whether different types of commercial cheeses may possess antiproliferative activity using HL-60 human promyelocytic leukemia cell lines as a cancer model. Among 12 cheese extracts tested, 6 (Montagnard, Pont-l'Eveque, Brie, Camembert, Danablue, and Blue) revealed strong growth inhibition activity and induction of DNA fragmentation in HL-60 cells. Based on the quantification of nitrogen contents in different cheese samples, a positive correlation between the ripeness of various cheeses and their antiproliferative activity tested in HL-60 cells was displayed. Four varieties of Blue cheese ripened for 0, 1, 2, or 3 mo demonstrated that the Blue cheese ripened for a long term was capable of causing the strong suppression of the cell growth and the induction of apoptotic DNA damage as well as nucleic morphological change in HL-60 cells. Collectively, these results obtained suggest a potential role of highly ripened cheeses in the prevention of leukemic cell proliferation. Copyright (c) 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  10. Movement as Spatial Practices and Economic Strategies in Cheese Production at Family Farms in Bohinj

    Directory of Open Access Journals (Sweden)

    Jaka Repič

    2014-07-01

    Full Text Available The article explores dairy and cheese production at family farms in Bohinj, their economical and organisational strategies (variations between family and cooperative organisation of farming and the connection of cheese production with different modes of spatial movement. In the past decade, several family farms have started producing cheese and milk products, which is an economic activity closely linked to traditional forms of cooperatives, and pasture rights of agricultural societies. These farms have revitalised traditional forms of cheese production and established new economic strategies, especially through the plurality of their activities – work outside of the farm, tourism, marketing of their products, etc. The article first presents a development of cheese production in Bohinj, changes in family and cooperative farming and explores movement and the meshwork of paths, tracks, roads and places that are fundamental to cheese economy. Further, the article connects different movements, e.g. daily pastures close to the villages, transhumance in mountain pasturelands, selling products in markets, etc. Modes of movement (walk, cattle herding, driving to markets are basic practices behind economic strategies of dairy and cheese farms, as well as organisations and use of space, in particular mountain paths and pasturelands.

  11. Potential of nisin-incorporated sodium caseinate films to control Listeria in artificially contaminated cheese.

    Science.gov (United States)

    Cao-Hoang, Lan; Chaine, Aline; Grégoire, Lydie; Waché, Yves

    2010-10-01

    A sodium caseinate film containing nisin (1000 IU/cm(2)) was produced and used to control Listeria innocua in an artificially contaminated cheese. Mini red Babybel cheese was chosen as a model semi-soft cheese. L. innocua was both surface- and in-depth inoculated to investigate the effectiveness of the antimicrobial film as a function of the distance from the surface in contact with the film. The presence of the active film resulted in a 1.1 log CFU/g reduction in L. innocua counts in surface-inoculated cheese samples after one week of storage at 4 degrees C as compared to control samples. With regard to in-depth inoculated cheese samples, antimicrobial efficiency was found to be dependent on the distance from the surface in contact with the active films to the cheese matrix. The inactivation rates obtained were 1.1, 0.9 and 0.25 log CFU/g for distances from the contact surface of 1 mm, 2 mm and 3 mm, respectively. Our study demonstrates the potential application of sodium caseinate films containing nisin as a promising method to overcome problems associated with post-process contamination, thereby extending the shelf life and possibly enhancing the microbial safety of cheeses. 2010 Elsevier Ltd. All rights reserved.

  12. Action of the ionization treatment on the soft cheeses made from unpasteurized milk

    International Nuclear Information System (INIS)

    Chincholle, R.

    1991-01-01

    The works made on cheeses manufactured with unpasteurized milk, camembert type, have shown that it is possible to use irradiation for their sanitation. The treatment by ionization from 2 to 3 kGy of a cheese made from unpasteurized milk permits the reduction from 10 3 to 10 5 of the bacteria: faecal coliforms, staphylococcus and other indesirable bacteria. The works made by the scientists, J.F. Diell, C. Hauchmann, D. Rilcast, proved that ionization of food has no bad consequences in the nutritional field. Regarding the cheeses made with raw milk this technic brings to the consumer a higher bacteriological security

  13. Quantification of pizza baking properties of different cheeses, and their correlation with cheese functionality.

    Science.gov (United States)

    Ma, Xixiu; Balaban, Murat O; Zhang, Lu; Emanuelsson-Patterson, Emma A C; James, Bryony

    2014-08-01

    The aim of this study is to quantify the pizza baking properties and performance of different cheeses, including the browning and blistering, and to investigate the correlation to cheese properties (rheology, free oil, transition temperature, and water activity). The color, and color uniformity, of different cheeses (Mozzarella, Cheddar, Colby, Edam, Emmental, Gruyere, and Provolone) were quantified, using a machine vision system and image analysis techniques. The correlations between cheese appearance and attributes were also evaluated, to find that cheese properties including elasticity, free oil, and transition temperature influence the color uniformity of cheeses. © 2014 Institute of Food Technologists®

  14. Avaliação sensorial e reológica de uma bebida achocolatada elaborada a partir de extrato hidrossolúvel de soja e soro de queijo =Sensorial and rheologic evaluation of a chocolate-based drink produced with water-soluble soybean extract and cheese whey

    Directory of Open Access Journals (Sweden)

    Ricardo Wagner Mori Moreira

    2010-10-01

    Full Text Available A soja é um alimento rico em proteínas e seu custo é menor quandocomparado à proteína animal. No entanto, ainda é pouco consumida, principalmente no Ocidente. O soro de queijo é um subproduto da indústria de laticínios, originado a partir da produção de queijos. É muito prejudicial ao meio ambiente quando descartado de forma inadequada, por ser um poluente em potencial. Seu tratamento, geralmente, é dispendioso e a sua composição é rica em nutrientes necessários para a dieta humana. Nesse contexto, foram elaboradas diferentes formulações de bebida achocolatada, contendo extratohidrossolúvel de soja (EHS e/ou soro de queijo com a finalidade de se verificar a aceitação sensorial das formulações em relação aos atributos cor, sabor e consistência. Foi também realizada a caracterização reológica das amostras, nas temperaturas de 10 e 20°C. Os resultados mostraram que a formulação elaborada somente com soro apresentou maior aceitação sensorial em relação aos atributos sabor e consistência. Em contrapartida, nessa mesma formulação, foi verificado menor índice de consistência do fluido e pseudoplasticidade.Soy is a food rich in proteins and its cost is lower when compared to animal protein. However, it is still underconsumed, especially in the Western world. Cheese whey is a byproduct of the dairy industry originated from the production of cheese, and is very harmful to the environment when disposed improperly, given that it then might become a pollutant. Its treatment is usually expensive, but its composition is quite rich in nutrients needed in the human diet. In this context, five different formulations of a chocolate-based drink were produced using soybean and/or cheese whey, with the purpose of assessing the sensorial acceptance of the formulations regarding attributes like color, flavor and consistency. For the prepared samples, rheological characterizations were also performed in the temperatures of 10

  15. Impact of selected coagulants and starters on primary proteolysis and amino acid release related to bitterness and structure of reduced-fat Cheddar cheese

    DEFF Research Database (Denmark)

    Børsting, Mette Winther; Qvist, Karsten Bruun; Rasmussen, Morten

    2012-01-01

    Despite substantial research, it is still difficult to produce high quality reduced-fat Cheddar cheese. The objective of this study was to investigate how two coagulants, bovine chymosin (BC) and camel chymosin (CC) having different proteolytic activities and two starter cultures, an O-culture (O...... cheeses with BC had a higher amount of peptides released by chymosin, e. g. the bitter peptide beta-casein (f193-209) or by starter proteases from the chymosin-produced peptide alpha(s1)-CN (f1-23). BC cheeses were also judged to be softer by the sensory panel. Cheeses containing the OLb-culture had...

  16. Cheese and cardiovascular disease risk

    DEFF Research Database (Denmark)

    Hjerpsted, Julie Bousgaard; Tholstrup, Tine

    2016-01-01

    Abstract Currently, the effect of dairy products on cardiovascular risk is a topic with much debate and conflicting results. The purpose of this review is to give an overview of the existing literature regarding the effect of cheese intake and risk of cardiovascular disease (CVD). Studies included...

  17. Multi-detection of preservatives in cheeses by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Fuselli, Fabio; Guarino, Chiara; La Mantia, Alessandro; Longo, Lucia; Faberi, Angelo; Marianella, Rosa Maria

    2012-10-01

    The incorrect use of preservatives in cheeses may compromise food safety and damage consumers. According to the law, more than one preservative may be contemporarily used in cheeses. So a method for their contemporary detection may be useful for both manufacturers and control agencies quality control. In this research a liquid chromatography-tandem mass spectrometric with electrospray ionization method for the multi-determination of seven preservatives (benzoic acid, citric acid, hexamethylenetetramine, lysozyme, natamycin, nisin and sorbic acid) in cheese was developed. The preservatives were contemporarily extracted from cheese by a single procedure, and analyzed by RP-LC/ESI-MS/MS (Ion Trap) in positive ionization mode, with single reaction monitoring (SRM) acquisition. Three sample types (hard, pasta filata and fresh cheese) were used for method evaluation. Recoveries were mostly higher than 90%; MDLs ranged from 0.02 to 0.26 mgkg(-1), and MQLs were included between 0.07 and 0.88 mgkg(-1). Due to matrix effect, quantitation was performed by referring to a matrix matched calibration curve, for each cheese typology. This method was also applied to commercial cheese samples, with good results. It appears fast, reliable and suitable for both screening and confirmation of the presence and quantitation of the preservatives in a single, multi-detection analysis. Copyright © 2012 Elsevier B.V. All rights reserved.

  18. Formation of early and advanced Maillard reaction products correlates to the ripening of cheese.

    Science.gov (United States)

    Spanneberg, Robert; Salzwedel, Grit; Glomb, Marcus A

    2012-01-18

    The present study deals with the characterization of the ripening of cheese. A traditional German acid curd cheese was ripened under defined conditions at elevated temperature, and protein and amino acid modifications were investigated. Degree of proteolysis and analysis of early [Amadori compound furosine (6)] and advanced [N(ε)-carboxymethyllysine (4), N(ε)-carboxyethyllysine (5)] Maillard reaction products confirmed the maturation to proceed from the rind to the core of the cheese. Whereas 6 was decreased, 4 and 5 increased over time. Deeper insight into the Maillard reaction during the ripening of cheese was achieved by the determination of selected α-dicarbonyl compounds. Especially methylglyoxal (2) showed a characteristic behavior during storage of the acid curd cheese. Decrease of this reactive structure was directly correlated to the formation of 5. To extend the results of experimental ripening to commercial cheeses, different aged Gouda types were investigated. Maturation times of the samples ranged from 6 to 8 weeks (young) to more than 1 year (aged). Again, increase of 5 and decrease of 2 were able to describe the ripening of this rennet coagulated cheese. Therefore, both chemical parameters are potent markers to characterize the degree of maturation, independent of coagulation.

  19. Molecular Identification and Quantification of Tetracycline and Erythromycin Resistance Genes in Spanish and Italian Retail Cheeses

    Directory of Open Access Journals (Sweden)

    Ana Belén Flórez

    2014-01-01

    Full Text Available Large antibiotic resistance gene pools in the microbiota of foods may ultimately pose a risk for human health. This study reports the identification and quantification of tetracycline- and erythromycin-resistant populations, resistance genes, and gene diversity in traditional Spanish and Italian cheeses, via culturing, conventional PCR, real-time quantitative PCR (qPCR, and denaturing gradient gel electrophoresis (DGGE. The numbers of resistant bacteria varied widely among the antibiotics and the different cheese varieties; in some cheeses, all the bacterial populations seemed to be resistant. Up to eight antibiotic resistance genes were sought by gene-specific PCR, six with respect to tetracycline, that is, tet(K, tet(L, tet(M, tet(O, tet(S, and tet(W, and two with respect to erythromycin, that is, erm(B and erm(F. The most common resistance genes in the analysed cheeses were tet(S, tet(W, tet(M, and erm(B. The copy numbers of these genes, as quantified by qPCR, ranged widely between cheeses (from 4.94 to 10.18log⁡10/g. DGGE analysis revealed distinct banding profiles and two polymorphic nucleotide positions for tet(W-carrying cheeses, though the similarity of the sequences suggests this tet(W to have a monophyletic origin. Traditional cheeses would therefore appear to act as reservoirs for large numbers of many types of antibiotic resistance determinants.

  20. Secondary metabolites from Penicillium roqueforti, a starter for the production of Gorgonzola cheese

    Directory of Open Access Journals (Sweden)

    Lisa Vallone

    2014-09-01

    Full Text Available The presence of mold in food, although necessary for production, can involve the presence of secondary metabolites, which are sometimes toxic. Penicillium roqueforti is a common saprophytic fungus but it is also the essential fungus used in the production of Roquefort cheese and other varieties of blue cheese containing internal mold. The study was conducted on industrial batches of Penicillium roqueforti starters used in the production of the Gorgonzola cheese, with the aim to verify the production of secondary metabolites. Nine Penicillium roqueforti strains were tested. The presence of roquefortine C, PR toxin and mycophenolic acid was tested first in vitro, then on bread-like substrate and lastly in vivo in nine cheese samples produced with the same starters and ready to market. In vitro, only Penicillium out of nine produced roquefortine C, four starters showed mycophenolic acid production, while no significant amounts of PR toxin were detected. In the samples grown on bread-like substrate, Penicillium did not produce secondary metabolites, likewise with each cheese samples tested. To protect consumers’ health and safety, the presence of mycotoxins needs to be verified in food which is widely consumed, above all for products protected by the protected denomination of origin (DOP label (i.e. a certificate guaranteeing the geographic origin of the product, such as Gorgonzola cheese.

  1. PRODUCTION UNDER CONTROLLED CONDITIONS OF “CASU MARZU” CHEESE: EFFECT OF THE Piophila Casei COLONIZATION ON MICROBIAL AND CHEMICAL COMPOSITION OF THE CHEESES

    Directory of Open Access Journals (Sweden)

    M Coinu

    2013-02-01

    Full Text Available The aim of the present study was to evaluate the effect of the Piophila casei colonization under controlled conditions on “casu marzu”, a typical Sardinian sheep milk cheese. Three batches of two different kind of cheese (PO, holed paste and PC, firm paste were produced in duplicate (test and control. Test cheeses were exposed to the Piophila casei colonization in a conditioned store room, while control cheeses were suitably protected. All the samples were analyzed at 0, 10, 30, 60 and 90 days from the production. The pH and aw, the chemical composition and the microbiological parameters (food safety and process hygiene criteria were determined. The colonization was unhomogeneous between the batches: PO cheeses were more easily colonized and showed more intense proteolysis and lipolysis respect to PC cheeses. The microbiological parameters were strongly affected by the experimental process conditions. The authors discuss about the opportunity of a controlled production of “casu marzu” and the implications to the health of consumers.

  2. Bacteriophage biocontrol of Listeria monocytogenes on soft ripened white mold and red-smear cheeses.

    Science.gov (United States)

    Guenther, Susanne; Loessner, Martin J

    2011-03-01

    Soft-ripened cheeses belong to the type of food most often contaminated with Listeria monocytogenes, and they have been implicated in several outbreaks of listeriosis. Bacteriophages represent an attractive way to combat foodborne pathogens without affecting other properties of the food. We used the broad host range, virulent Listeria phage A511 for control of L. monocytogenes during the production and ripening phases of both types of soft-ripened cheeses, white mold (Camembert-type) cheese, as well as washed-rind cheese with a red-smear surface (Limburger-type). The surfaces of young, unripened cheese were inoculated with 10(1)-10(3) cfu/cm(2)L. monocytogenes strains Scott A (serovar 4b) or CNL 10(3)/2005 (serovar 1/2a). Phage was applied at defined time points thereafter, in single or repeated treatments, at 3 × 10(8) or 1 × 10(9) pfu/cm(2). With Scott A (10(3) cfu/cm(2)) and a single dose of A511 (3 × 10(8) pfu/cm(2)) on camembert-type cheese, viable counts dropped 2.5 logs at the end of the 21 day ripening period. Repeated phage application did not further inhibit the bacteria, whereas a single higher dose (1 × 10(9) pfu/cm(2)) was found to be more effective. On red-smear cheese ripened for 22 days, Listeria counts were down by more than 3 logs. Repeated application of A511 further delayed re-growth of Listeria, but did not affect bacterial counts after 22 days. With lower initial Listeria contamination (10(1)-10(2) cfu/cm(2)), viable counts dropped below the limit of detection, corresponding to more than 6 logs reduction compared to the control. Our data clearly demonstrate the potential of bacteriophage for biocontrol of L. monocytogenes in soft cheese.

  3. Complete genome sequence of Corynebacterium variabile DSM 44702 isolated from the surface of smear-ripened cheeses and insights into cheese ripening and flavor generation

    Directory of Open Access Journals (Sweden)

    Trost Eva

    2011-11-01

    Full Text Available Abstract Background Corynebacterium variabile is part of the complex microflora on the surface of smear-ripened cheeses and contributes to the development of flavor and textural properties during cheese ripening. Still little is known about the metabolic processes and microbial interactions during the production of smear-ripened cheeses. Therefore, the gene repertoire contributing to the lifestyle of the cheese isolate C. variabile DSM 44702 was deduced from the complete genome sequence to get a better understanding of this industrial process. Results The chromosome of C. variabile DSM 44702 is composed of 3, 433, 007 bp and contains 3, 071 protein-coding regions. A comparative analysis of this gene repertoire with that of other corynebacteria detected 1, 534 predicted genes to be specific for the cheese isolate. These genes might contribute to distinct metabolic capabilities of C. variabile, as several of them are associated with metabolic functions in cheese habitats by playing roles in the utilization of alternative carbon and sulphur sources, in amino acid metabolism, and fatty acid degradation. Relevant C. variabile genes confer the capability to catabolize gluconate, lactate, propionate, taurine, and gamma-aminobutyric acid and to utilize external caseins. In addition, C. variabile is equipped with several siderophore biosynthesis gene clusters for iron acquisition and an exceptional repertoire of AraC-regulated iron uptake systems. Moreover, C. variabile can produce acetoin, butanediol, and methanethiol, which are important flavor compounds in smear-ripened cheeses. Conclusions The genome sequence of C. variabile provides detailed insights into the distinct metabolic features of this bacterium, implying a strong adaption to the iron-depleted cheese surface habitat. By combining in silico data obtained from the genome annotation with previous experimental knowledge, occasional observations on genes that are involved in the complex

  4. Comparison of Antibacterial Activity of Lactobacillus plantarum Strains Isolated from Two Different Kinds of Regional Cheeses from Poland: Oscypek and Korycinski Cheese

    Directory of Open Access Journals (Sweden)

    Aleksandra Ołdak

    2017-01-01

    Full Text Available Oscypek and korycinski are traditional Polish cheeses, exclusively produced in Tatra and in Podlasie region, respectively, produced from raw, unpasteurized milk. The 29 Lactobacillus plantarum strains were isolated on MRS agar from 12 cheese samples and used as a material for study. The main purpose of the work was to assess the antimicrobial properties and recognition of selected strains for the unique antagonistic activity and preservation role in food. It has been found that the highest antimicrobial activity was observed in the case of L. monocytogenes strains; however, the level of that activity was different depending on the Lb. plantarum strain. Strains from oscypek produced broad spectrum, and a few strains isolated from korycinski cheese produced a narrow spectrum of antimicrobial compounds, other than organic acids and hydrogen peroxide. Moreover, the antagonistic activity shown by Lb. plantarum strains is connected with the source from which a given strain was isolated. Strains isolated from oscypek cheese represented stronger activity against L. monocytogenes, whereas strains isolated from korycinski cheese were more active against E. coli. Strains Lb. plantarum Os13 and Kor14 could be considered as good candidates for protective cultures to extend durability of food products.

  5. Comparison of Antibacterial Activity of Lactobacillus plantarum Strains Isolated from Two Different Kinds of Regional Cheeses from Poland: Oscypek and Korycinski Cheese

    Science.gov (United States)

    Ołdak, Aleksandra; Rzepkowska, Anna

    2017-01-01

    Oscypek and korycinski are traditional Polish cheeses, exclusively produced in Tatra and in Podlasie region, respectively, produced from raw, unpasteurized milk. The 29 Lactobacillus plantarum strains were isolated on MRS agar from 12 cheese samples and used as a material for study. The main purpose of the work was to assess the antimicrobial properties and recognition of selected strains for the unique antagonistic activity and preservation role in food. It has been found that the highest antimicrobial activity was observed in the case of L. monocytogenes strains; however, the level of that activity was different depending on the Lb. plantarum strain. Strains from oscypek produced broad spectrum, and a few strains isolated from korycinski cheese produced a narrow spectrum of antimicrobial compounds, other than organic acids and hydrogen peroxide. Moreover, the antagonistic activity shown by Lb. plantarum strains is connected with the source from which a given strain was isolated. Strains isolated from oscypek cheese represented stronger activity against L. monocytogenes, whereas strains isolated from korycinski cheese were more active against E. coli. Strains Lb. plantarum Os13 and Kor14 could be considered as good candidates for protective cultures to extend durability of food products. PMID:28626762

  6. Irradiation of 'minas frescal' cheese: physical-chemical aspects

    International Nuclear Information System (INIS)

    Gurgel, Maria Sylvia de C.C. do Amaral; Spoto, Marta H.F.; Domardo, Raquel E.; Gutierrez, Erica Maria Roel

    2000-01-01

    The present work studied the viability of gamma radiation as alternative method of conservation 'minas frescal' cheese through by determining its effect on the physical-chemical properties of this product after irradiation. Cheese elaborated in the Laboratory of Food Irradiation CENA/USP, were exposed to doses of 0 (it controls); 1; 2; 3 and 4 kGy and stored under refrigeration (±5 deg C). The analysis were accomplished in the 1st, 7th and 14th day of storage considered the following parameters: acidity, pH, moisture and level of proteolysis according to methodology of Association of Official Analytical Chemists (A.O.A.C.),1995. The results revealed that the dose of 2 kGy was the most indicated for irradiation of that type of cheese, because after this treatment, the product maintained in good conditions for consumption after 14 days of storage. It was concluded that gamma radiation can be used as a method of conservation of 'minas frescal' cheese, without causing alterations in its physical-chemical characteristics. (author)

  7. Mycotoxicogenic fungal inhibition by innovative cheese cover with aromatic plants.

    Science.gov (United States)

    Moro, Armando; Librán, Celia M; Berruga, M Isabel; Zalacain, Amaya; Carmona, Manuel

    2013-03-30

    The use of aromatic plants and their extracts with antimicrobial properties may be compromised in the case of cheese, as some type of fungal starter is needed during its production. Penicillium verrucosum is considered a common cheese spoiler. The aim of this study was to evaluate the innovative use of certain aromatic plants as natural cheese covers in order to prevent mycotoxicogenic fungal growth (P. verrucosum). A collection of 12 essential oils (EOs) was obtained from various aromatic plants by solvent-free microwave extraction technology, and volatile characterisation of the EOs was carried out by gas chromatography/mass spectrometry. The most effective EOs against P. verrucosum were obtained from Anethum graveolens, Hyssopus officinalis and Chamaemelum nobile, yielding 50% inhibition of fungal growth at concentration values lower than 0.02 µL mL⁻¹. All EOs showed high volatile heterogeneity, with α-phellandrene, pinocamphone, isopinocamphone, α-pinene, camphene, 1,8-cineole, carvacrol and trans-anethole being found to be statistically significant in the antifungal model. The use of these aromatic plants as natural covers on cheese can satisfactorily inhibit the growth of some mycotoxicogenic fungal spoilers. Among the volatile compounds present, α- and β-phellandrene were confirmed as the most relevant in the inhibition. © 2012 Society of Chemical Industry.

  8. Modeling the growth of Listeria monocytogenes in soft blue-white cheese

    DEFF Research Database (Denmark)

    Rosshaug, Per Sand; Detmer, Ann; Ingmer, Hanne

    2012-01-01

    The aim of this study was to develop a predictive model simulating growth over time of the pathogenic bacterium Listeria monocytogenes in a soft blue-white cheese. The physicochemical properties in a matrix such as cheese are essential controlling factors influencing the growth of L. monocytogenes....... We developed a predictive tertiary model of the bacterial growth of L. monocytogenes as a function of temperature, pH, NaCl, and lactic acid. We measured the variations over time of the physicochemical properties in the cheese. Our predictive model was developed based on broth data produced...... production and retail conditions showed that the number of L. monocytogenes cells increases 3 to 3.5 log within the shelf life of the cheese....

  9. Development of selective medium for IMP-type carbapenemase-producing Enterobacteriaceae in stool specimens.

    Science.gov (United States)

    Yamamoto, Norihisa; Kawahara, Ryuji; Akeda, Yukihiro; Shanmugakani, Rathina Kumar; Yoshida, Hisao; Hagiya, Hideharu; Hara, Naohiro; Nishi, Isao; Yukawa, Satomi; Asada, Rumiko; Sasaki, Yumi; Maeda, Kazuhiro; Sakamoto, Noriko; Hamada, Shigeyuki; Tomono, Kazunori

    2017-03-24

    Identification of carbapenemase-producing Enterobacteriaceae (CPE) in faecal specimens is challenging. This fact is particularly critical because low-level carbapenem-resistant organisms such as IMP-producing CPE are most prevalent in Japan. We developed a modified selective medium more suitable for IMP-type CPE. Fifteen reference CPE strains producing different types of β-lactamases were used to evaluate the commercially available CHROMagar KPC and chromID CARBA as well as the newly prepared MC-ECC medium (CHROMagar ECC supplemented with meropenem, cloxacillin, and ZnSO 4 ) and M-ECC medium (CHROMagar ECC supplemented with meropenem and ZnSO 4 ). A total of 1035 clinical samples were then examined to detect CPE using chromID CARBA and M-ECC medium. All tested strains producing NDM-, KPC-, and OXA-48-carbapenemases were successfully cultured in the media employed. Although most of the IMP-positive strains did not grow in CHROMagar KPC, chromID CARBA, or MC-ECC, all tested strains grew on M-ECC. When faecal samples were applied to the media, M-ECC medium allowed the best growth of IMP-type CPE with a significantly higher sensitivity (99.3%) than that of chromID CARBA (13.9%). M-ECC medium was determined as the most favourable selective medium for the detection of IMP-type CPE as well as other types of CPE.

  10. Improvements in the Flavour of Soy Cheese

    Directory of Open Access Journals (Sweden)

    Naveed Ahmad

    2008-01-01

    Full Text Available A review of biochemical and technological similarities and dissimilarities between soy cheese and Cheddar cheese is presented to provide guidelines for the improvements in the flavour of soy cheese. Processing technology as well as the final product of soy cheese have many similarities with Cheddar in terms of appearance, texture, mouth feel, chemical nature, biochemical processes, etc. Soy protein has many useful amino acids like Asp, Ile, Leu, Met, Phe, Trp, Tyr, Val, etc., which are precursors of flavouring compounds and the right choice of microbial cultures is necessary to benefit from them. Using low levels of sodium chloride, without the use of ethanol, and introducing new milk cheese starter and non-starter cultures like Lactococcus lactis ssp. lactis (formerly L. lactis ssp. lactis biovar. diacetylactis, Lactobacillus helveticus, Lactobacillus casei, Streptococcus lactis var. maltigenes and Lactococcus lactis ssp. cremoris that enhance flavour will be helpful to improve the flavour of soy cheese.

  11. Transference of lutein during cheese making, color stability, and sensory acceptance of prato cheese

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    Mirian Tiaki Kaneiwa Kubo

    2013-02-01

    Full Text Available The consumption of lutein is associated with the prevention and reduction of age-related macular degeneration. Its incorporation into Prato cheese as a yellowish food coloring is a valid alternative to increase the daily intake of this compound. However, part of the lutein added may be lost in the whey during the cheese making, or it can be degraded by light during storage, resulting in color changes reducing the sensory acceptance of the cheese. The objectives of this study were to determine the transference of the lutein (dye, added to the milk, in the whey, and cheese, to evaluate the effect of the lutein addition, light exposure, and storage time on the cheese color, and to verify the sensory acceptance of Prato cheese with addition of lutein. The lutein recovery of cheese was 95.25%. Color saturation (chrome increased during storage time resulting in a cheese with more intense color, but there were no changes in the hue of the cheese. Adjusting the amount of lutein added to Prato cheese may lead to greater acceptance. The high recovery of lutein in the cheese and the fact that the hue remained unchanged during storage under light showed that the incorporation of lutein into Prato cheese is feasible from a technical point of view.

  12. Evaluation of biogenic amines and microbial counts throughout the ripening of goat cheeses from pasteurized and raw milk.

    Science.gov (United States)

    Novella-Rodríguez, Sonia; Veciana-Nogués, M Teresa; Roig-Sagués, Artur X; Trujillo-Mesa, Antonio J; Vidal-Carou, M Carmen

    2004-05-01

    The effect of the hygienic quality of milk on changes in microbial counts and biogenic amine content was evaluated during ripening of goat cheeses manufactured from pasteurized and raw milks at 1, 14, 30, 60 and 90 d. The original milk, rennet, curd and whey were also included in the study. The pH, salt content and extent of proteolysis in the cheese were also evaluated. Spermidine and spermine were the main amines in raw milk, while they were minor amines in cheeses. Other amines increased markedly during ripening, tyramine being the main amine in cheese made from raw milk and cadaverine and putrescine in those produced from pasteurized milk. Enterobacteriaceae counts decreased during ripening whereas those of lactic acid bacteria increased, especially lactobacilli and enterococci. Cheese made from raw milk showed higher microbial counts during ripening than those made from pasteurized milk, especially for Enterobacteriaceae and enterococci, counts being 2 or 3 log units higher. Raw milk cheese showed remarkably higher biogenic amines compared with pasteurized milk cheeses. Therefore, pasteurization of milk causes a decrease in final biogenic amine content of cheese as a result of the reduction of its microbial counts.

  13. Evaluation of hygiene and safety criteria in the production of a traditional Piedmont cheese

    Directory of Open Access Journals (Sweden)

    Sara Astegiano

    2014-08-01

    Full Text Available Traditional products and related processes must be safe to protect consumers’ health. The aim of this study was to evaluate microbiological criteria of a traditional Piedmont cheese, made by two different cheese producers (A and B. Three batches of each cheese were considered. The following seven samples of each batch were collected: raw milk, milk at 38°C, curd, cheese at 7, 30, 60, 90 days of ripening. During cheese making process, training activities dealing with food safety were conducted. Analyses regarding food safety and process hygiene criteria were set up according to the EC Regulation 2073/2005. Other microbiological and chemical-physical analyses [lactic streptococci, lactobacilli, pH and water activity (Aw] were performed as well. Shiga-toxin Escherichia coli, aflatoxin M1 and antimicrobial substances were considered only for raw milk. All samples resulted negative for food safety criteria; Enterobacteriaceae, E.coli and coagulase-positive staphylococci (CPS were high in the first phase of cheese production, however they decreased at the end of ripening. A high level of CPS in milk was found in producer A, likewise in some cheese samples a count of >5 Log CFU/g was reached; staphylococcal enterotoxins resulted negative. The pH and Aw values decreased during the cheese ripening period. The competition between lactic flora and potential pathogen microorganisms and decreasing of pH and Aw are considered positive factors in order to ensure safety of dairy products. Moreover, training activities play a crucial role to manage critical points and perform corrective action. Responsible application of good manufacturing practices are considered key factors to obtain a high hygienic level in dairy products.

  14. Evaluation of Hygiene and Safety Criteria in the Production of a Traditional Piedmont Cheese.

    Science.gov (United States)

    Astegiano, Sara; Bellio, Alberto; Adriano, Daniela; Bianchi, Daniela Manila; Gallina, Silvia; Gorlier, Alessandra; Gramaglia, Monica; Lombardi, Giampiero; Macori, Guerrino; Zuccon, Fabio; Decastelli, Lucia

    2014-08-28

    Traditional products and related processes must be safe to protect consumers' health. The aim of this study was to evaluate microbiological criteria of a traditional Piedmont cheese, made by two different cheese producers (A and B). Three batches of each cheese were considered. The following seven samples of each batch were collected: raw milk, milk at 38°C, curd, cheese at 7, 30, 60, 90 days of ripening. During cheese making process, training activities dealing with food safety were conducted. Analyses regarding food safety and process hygiene criteria were set up according to the EC Regulation 2073/2005. Other microbiological and chemical-physical analyses [lactic streptococci, lactobacilli, pH and water activity (A w )] were performed as well. Shiga-toxin Escherichia coli , aflatoxin M1 and antimicrobial substances were considered only for raw milk. All samples resulted negative for food safety criteria; Enterobacteriaceae , E.coli and coagulase-positive staphylococci (CPS) were high in the first phase of cheese production, however they decreased at the end of ripening. A high level of CPS in milk was found in producer A, likewise in some cheese samples a count of >5 Log CFU/g was reached; staphylococcal enterotoxins resulted negative. The pH and A w values decreased during the cheese ripening period. The competition between lactic flora and potential pathogen microorganisms and decreasing of pH and A w are considered positive factors in order to ensure safety of dairy products. Moreover, training activities play a crucial role to manage critical points and perform corrective action. Responsible application of good manufacturing practices are considered key factors to obtain a high hygienic level in dairy products.

  15. Bioaccessibility of essential elements from white cheese, bread, fruit and vegetables.

    Science.gov (United States)

    Khouzam, Rola Bou; Pohl, Pawel; Lobinski, Ryszard

    2011-10-30

    Bioaccessibility of five essential micronutrients (iron, zinc, copper, manganese and molybdenum) from the Lebanese food basket including bread, different varieties of white cheese, fruit and vegetables was evaluated using the in vitro gastrointestinal digestion model. Only very small fraction of Fe and Zn (ca. 10%) was found bioaccessible from bread, squash and cucumber. Iron in apple was not bioaccessible either (50%) in cheese was found to be bioaccessible but only one type of cheese, double crème, contained readily bioaccessible zinc. More than 50% of copper and molybdenum was found bioaccessible regardless of the investigated food. High bioaccessibility (>50%) was also observed for manganese in fruit and vegetables whereas that from bread and cheese was fair (25-30%). Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Type II textured molybdenum disulphide films produced by direct vapour transport and rf-magnetron sputtering

    International Nuclear Information System (INIS)

    Bohlken, S.F.; Lemon, K.D.; Jakovidis, G.; Taheri, E.H.

    1999-01-01

    Full text: Molybdenum disulphide (MoS 2 ) is one of the few naturally occurring Layered Transition Metal Dichalcogenides and is the primary source for elemental molybdenum. It displays exceptional lubrication performance in both vacuum and atmospheric conditions over a wide temperature range. An important emerging application of MoS 2 and related materials is photovoltaics. Films of MoS 2 exhibit several morphologies described by the orientation of platelets with respect to the substrate. Films with platelets perpendicular or parallel to the substrate are referred to by their morphology, which is type-I or type-II respectively. Production of exclusive type-II films is highly desirable in applications involving lubrication and photovoltaics. For example, type-II morphology reduces friction and minority carrier recombination centres, thus improving tribological and photovoltaic performance. We have successfully produced type-II films using both direct vapour transport and rf-magnetron sputtering Continuous polycrystalline films (∼ 10 μm thick) grown in our laboratory using vapour transport have typical areas 1000 mm 2 . A novel ejecta filtration technique was applied to rf-magnetron sputtering. Films produced using this approach retain exclusive type-II morphology at thicknesses where type-I would normally be observed (∼ 200nm)

  17. Cheese consumption and prevalence of overweight and obesity in a Basque adult population: a cross-sectional study.

    Science.gov (United States)

    Alegría-Lertxundi, Iker; Rocandio Pablo, Ana; Arroyo-Izaga, Marta

    2014-02-01

    Studies have reported a negative association between dairy product consumption and weight status. However, not as much research has focused on cheese; therefore, the aim of this study was to study the association between cheese intake and overweight and obesity in a representative Basque adult population. A food frequency questionnaire (FFQ) was obtained from a random sample of 1081 adults (530 males and 551 females, 17-96 years old). Cheese consumption data were expressed as g/1000 kcal/day. The prevalence of overweight/obesity was higher in men (55.1%) than in women (35.4%) (p processed cheese demonstrated a higher prevalence of excess weight, compared with those with higher consumption. The confounding variables selected in multivariate analysis were: occupational status and age in both genders; and place of residence in men. In conclusion, negative associations were found between consumption of some types of cheese and overweight and obesity in this population.

  18. Effect of starters and ripening time on the physicochemical, nitrogen fraction and texture profile of goat's cheese coagulated with a vegetable coagulant (Cynara cardunculus).

    Science.gov (United States)

    García, Víctor; Rovira, Silvia; Boutoial, Khalid; Ferrandini, Eduardo; López Morales, María B

    2014-02-01

    The increase in the demand for goat's cheese throughout the world has encouraged research into the development of new related products with different textural characteristics. The aim of this work was to study the effect of three commercial starter cultures through the assessment of physicochemical and textural characteristics of goat's milk cheeses made with vegetable coagulant (Cynara cardunculus) during ripening. Use of the different starter cultures produced a significant effect (P starters ensures the correct acidification rate and produced cheeses with lower pH values and greater hardness. Use of thermophilic starter cultures produces cheeses with less instrumental hardness and the use of mixed cultures produced less proteolysis. These results are found useful for selecting the most suitable starter for the development of new goat's cheeses. © 2013 Society of Chemical Industry.

  19. Varying occurrence of extended-spectrum beta-lactamase bacteria among three produce types

    KAUST Repository

    Toh, Benjamin E. W.

    2017-07-07

    A monitoring effort that spanned across 1.5 years was conducted to examine three types of produce-associated microbiota. The average amount of antibiotic-resistant bacteria recovered from lettuce, tomato, and cucumber was 1.02 × 1010, 2.05 × 107, and 4.78 × 109 cells per 50 g of each produce, respectively. A total of 480 bacterial isolates were obtained and identified from their 16S rRNA genes, revealing isolates that were ubiquitously recovered from all three types of produce. However, sporadic presence of Klebsiella pneumoniae and Acinetobacter baumannii was detected on lettuce and cucumbers but not tomatoes. End-point PCR revealed that the K. pneumoniae and A. baumannii isolates were positive for genes encoding extended spectrum beta-lactamase. Whole genome sequencing of two of the K. pneumoniae isolates further suggested the presence of the blaCTX-M-15 gene in a conjugative plasmid, as well as other antibiotic resistance genes and virulence-associated traits in either conjugative plasmids or the chromosomal genome. Quantitative microbial risk assessment indicated varying levels of ingestion risk associated with different types of produce. In particular, the risk arising from ESBL-positive K. pneumoniae in lettuce, but not in cucumbers or tomatoes, was higher than the acceptable annual risk of 10−4. Practical applications Three types of vegetables were sampled and evaluated over 1.5 years to determine differences in their associated bacterial isolates. Particular emphasis was placed on identifying pathogenic strains that were positive for extended spectrum beta-lactamase (ESBL). Quantitative estimates of the microbial risk associated with the ESBL-positive pathogens showed that different produce types may incur varying levels of ingestion risk. Most of the currently reported ESBL-positive bacterial isolates have been identified in nosocomial environments. However, the carriage of such drug-resistant bacteria in vegetables suggests a possible connection

  20. Mycotoxin production capability of Penicillium roqueforti in strains isolated from mould-ripened traditional Turkish civil cheese.

    Science.gov (United States)

    Cakmakci, Songul; Gurses, Mustafa; Hayaloglu, A Adnan; Cetin, Bulent; Sekerci, Pinar; Dagdemir, Elif

    2015-01-01

    Mould-ripened civil is a traditional cheese produced mainly in eastern Turkey. The cheese is produced with a mixture of civil and whey curd cheeses (lor). This mixture is pressed into goat skins or plastic bags and is ripened for more than three months. Naturally occurring moulds grow on the surface and inside of the cheese during ripening. In this research, 140 Penicillium roqueforti strains were isolated from 41 samples of mould-ripened civil cheese collected from Erzurum and around towns in eastern Turkey. All strains were capable of mycotoxin production and were analysed using an HPLC method. It was established that all the strains (albeit at very low levels) produced roquefortine C, penicillic acid, mycophenolic acid and patulin. The amounts of toxins were in the ranges 0.4-47.0, 0.2-43.6, 0.1-23.1 and 0.1-2.3 mg kg(-1), respectively. Patulin levels of the samples were lower than the others. The lowest level and highest total mycotoxin levels were determined as 1.2 and 70.1 mg kg(-1) respectively. The results of this preliminary study may help in the choice of secondary cultures for mould-ripened civil cheese and other mould-ripened cheeses.

  1. Situation and problems in the supply chains of traditional cheeses in Croatia

    Directory of Open Access Journals (Sweden)

    Željka Mesić

    2015-07-01

    Full Text Available Croatian producers of traditional cheeses often do not have the financial and/or organizational ability to act independently on the market, Thusit is important to get involved in supply chains in order to improve the competitiveness of their products. The main objective of this study was to determine the status and the problems related to the supply chains of traditional cheeses in Croatia. The survey was conducted on 36 chain members (including 12 milk suppliers, 12 cheese producers and 12 customers. In the first stage of the study cheese producers were selected for interviews. During the interviews, each cheese producer was asked to identify the most important suppliers and customers, which were subsequently forwarded the questionnaire depending on their role in the supply chain. According tothe obtained results the key problems in supply chains of traditional cheeseswere the imbalance in bargaining power within the chain, especially between producers and customers, the high logistics’ costs, the lack of transparency in contractual relations, low rates of charge realisation, and the poor communication and information sharing among supply chain members. Results of this study might be used as theoretical basis to all respondents whose companies participated in the survey and could encourage them to improve the performance of their supply chains based on the identified problems.

  2. The role of the canonical biplot method in the study of volatile compounds in cheeses of variable composition

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez Martin, M.I.; Vicente Tavera, S.; Revilla Martin, I.; Vivar Quintana, A.M.; Gonzalez Perez, C.; Hernandez Hierro, J.M.; Lobos Ortega, I.A.

    2016-07-01

    The canonical biplot method (CB) is used to determine the discriminatory power of volatile chemical compounds in cheese. These volatile compounds were used as variables in order to differentiate among 6 groups or populations of cheeses (combinations of two seasons (winter and summer) with 3 types of cheese (cow, sheep and goat’s milk). We analyzed a total of 17 volatile compounds by means of gas chromatography coupled with mass detection. The compounds included aldehydes and methyl-aldehydes, alcohols (primary, secondary and branched chain), ketones, methyl-ketones and esters in winter (WC) and summer (SC) cow’s cheeses, winter (WSh) and summer (SSh) sheep’s cheeses and in winter (WG) and summer (SG) goat’s cheeses. The CB method allows differences to be found as a function of the elaboration of the cheeses, the seasonality of the milk, and the separation of the six groups of cheeses, characterizing the specific volatile chemical compounds responsible for such differences. (Author)

  3. Cheese whey management: a review.

    Science.gov (United States)

    Prazeres, Ana R; Carvalho, Fátima; Rivas, Javier

    2012-11-15

    Cheese whey is simultaneously an effluent with nutritional value and a strong organic and saline content. Cheese whey management has been focused in the development of biological treatments without valorization; biological treatments with valorization; physicochemical treatments and direct land application. In the first case, aerobic digestion is reported. In the second case, six main processes are described in the literature: anaerobic digestion, lactose hydrolysis, fermentation to ethanol, hydrogen or lactic acid and direct production of electricity through microbial fuel cells. Thermal and isoelectric precipitation, thermocalcic precipitation, coagulation/flocculation, acid precipitation, electrochemical and membrane technologies have been considered as possible and attractive physicochemical processes to valorize or treat cheese whey. The direct land application is a common and longstanding practice, although some precautions are required. In this review, these different solutions are analyzed. The paper describes the main reactors used, the influence of the main operating variables, the microorganisms or reagents employed and the characterizations of the final effluent principally in terms of chemical oxygen demand. In addition, the experimental conditions and the main results reported in the literature are compiled. Finally, the comparison between the different treatment alternatives and the presentation of potential treatment lines are postulated. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Antimicrobial susceptibility of microflora from ovine cheese.

    Science.gov (United States)

    Kmeť, V; Drugdová, Z

    2012-07-01

    Strains identified in ovine cheese and bryndza by matrix-assisted laser desorption/ionization time-of-flight analysis belonged to ten species of non-enterococcal lactic acid bacteria and included Lactobacillus casei/Lactobacillus paracasei, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactobacillus helveticus, Lactobacillus delbrueckii, Lactobacillus fermentum, Lactobacillus brevis, Lactococcus lactis, Pediococcus pentosaceus and Pediococcus acidilactici. The susceptibility toward antibiotics was determined in lactobacilli, lactococci and pediococci and also in Escherichia coli for comparison. Analysis of L. fermentum and pediococci revealed the presence of non-wild-type epidemiological cut-offs in streptomycin, clindamycin or gentamicin. E. coli were resistant to ampicillin, tetracycline, enrofloxacin and florfenicol. No extended spectrum β-lactamases were detected.

  5. Impact of NaCl reduction in Danish semi-hard Samsoe cheeses on proliferation and autolysis of DL-starter cultures.

    Science.gov (United States)

    Søndergaard, Lise; Ryssel, Mia; Svendsen, Carina; Høier, Erik; Andersen, Ulf; Hammershøj, Marianne; Møller, Jean R; Arneborg, Nils; Jespersen, Lene

    2015-11-20

    Reduction of sodium chloride (NaCl) in cheese manufacturing is a challenge for the dairy industry. NaCl has a profound role on microbial development influencing cheese sensory and technological properties. The purpose of this work was to investigate how proliferation, distribution and autolysis of two commercial DL-starter cultures (C1 and C2) used in the production of Danish semi-hard Samsoe cheeses were affected by reduced NaCl levels. Cheeses containing autolysis were monitored during ripening, as well as the impact of NaCl content and autolysis on the formation of free amino acids (FAA). Reduction of NaCl resulted in higher LAB counts at the early stages of ripening, with differences between the two DL-starter cultures. The unsalted cheeses produced with C1 had retained a significantly higher number of the initial LAB counts (cfu/g) after 1 and 2 weeks of ripening (i.e. 58% and 71%), compared to the normal-salted cheeses (i.e. 22% and 21%), whereas no significant difference was found between the reduced-salt (i.e. 31% and 35%) and normal-salted cheeses. At the later stages of ripening (i.e. 7 and 11 weeks) NaCl had no significant influence. For cheeses produced with C2, a significant influence of NaCl was only found in cheeses ripened for 7 weeks, where the unsalted and reduced-salt cheeses had retained a significantly higher number of the initial LAB counts (cfu/g) (i.e. 39% and 38%), compared to the normal-salted cheeses (i.e. 21%). In the Samsoe cheeses, bacteria were organized as single cells, in groups of 2-3 cells or in groups of ≥4 cells. During ripening the decrease in the number of viable bacteria was mainly due to a reduction in the number of viable bacteria organized in groups of ≥4 cells. A negative correlation between NaCl content and PepX activity was observed. At the end of ripening the total FAA content was lower in the unsalted cheeses, compared to the reduced- and normal-salted cheeses. In conclusion, NaCl had a significant influence on

  6. First isolate of KPC-2-producing Klebsiella pneumonaie sequence type 23 from the Americas.

    Science.gov (United States)

    Cejas, Daniela; Fernández Canigia, Liliana; Rincón Cruz, Giovanna; Elena, Alan X; Maldonado, Ivana; Gutkind, Gabriel O; Radice, Marcela A

    2014-09-01

    KPC-2-producing Klebsiella pneumoniae isolates mainly correspond to clonal complex 258 (CC258); however, we describe KPC-2-producing K. pneumoniae isolates belonging to invasive sequence type 23 (ST23). KPC-2 has scarcely been reported to occur in ST23, and this report describes the first isolation of this pathogen in the Americas. Acquisition of resistant markers in virulent clones could mark an evolutionary step toward the establishment of these clones as major nosocomial pathogens. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  7. Microstructure and physicochemical properties reveal differences between high moisture buffalo and bovine Mozzarella cheeses.

    Science.gov (United States)

    Nguyen, Hanh T H; Ong, Lydia; Lopez, Christelle; Kentish, Sandra E; Gras, Sally L

    2017-12-01

    Mozzarella cheese is a classical dairy product but most research to date has focused on low moisture products. In this study, the microstructure and physicochemical properties of both laboratory and commercially produced high moisture buffalo Mozzarella cheeses were investigated and compared to high moisture bovine products. Buffalo and bovine Mozzarella cheeses were found to significantly differ in their microstructure, chemical composition, organic acid and proteolytic profiles but had similar hardness and meltability. The buffalo cheeses exhibited a significantly higher ratio of fat to protein and a microstructure containing larger fat patches and a less dense protein network. Liquid chromatography mass spectrometry detected the presence of only β-casein variant A2 and a single β-lactoglobulin variant in buffalo products compared to the presence of both β-casein variants A1 and A2 and β-lactoglobulin variants A and B in bovine cheese. These differences arise from the different milk composition and processing conditions. The differences in microstructure and physicochemical properties observed here offer a new approach to identify the sources of milk used in commercial cheese products. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Cesium-134 and cesium-137 in honey bees and cheese samples collected in the U. S. after the Chernobyl accident

    Energy Technology Data Exchange (ETDEWEB)

    Ford, B C; Jester, W A; Griffith, S M; Morse, R A; Zall, R R; Lisk, D J; Burgett, D M; Bodyfelt, F W

    1988-01-01

    As a result of the Chernobyl accident on April 25, 1986, possible radioactive contamination of honey bees and cheese sampled in several areas of the United States were measured. Of bees collected in May and June of 1986 in both Oregon and New York, only those from Oregon showed detectable levels of cesium-134 (T1/2 = 2.05 years), a radionuclide which would have originated from the Chernobyl incident. Cheese produced in Oregon and New York before the accident showed only cesium-137 (T1/2 = 30.23 years) but cheese produced afterwards (May and September, 1986) in Oregon contained cesium-134. Cheese produced in Ohio and California at the time of the accident and thereafter contained only cesium-137. In general, the levels of radioactivity were higher in the West coast samples as compared to those taken in the East. The levels of radioactivity detected were considered to be toxicologically of no consequence.

  9. Comparison of the acidifying activity of Lactococcus lactis subsp. lactis strains isolated from goat's milk and Valdeteja cheese.

    Science.gov (United States)

    Alonso-Calleja, C; Carballo, J; Capita, R; Bernardo, A; García-López, M L

    2002-01-01

    This work was carried out to study the acid production by Lactococcus lactis subsp. lactis strains isolated from goat's milk and goat cheese (Valdeteja variety) in order to select a suitable starter culture for industrial goat cheese manufacturing. The titrable acidity of 45 Lactococcus lactis subsp. lactis strains isolated from a home-made batch of Valdeteja cheese with excellent sensory characteristics was measured over a period of 18 h. The strains were divided into two groups depending on the acid production rate: 20 fast acid producer (F) strains and 25 slow acid producer (S) strains. The kinetic parameters (lag phase, maximum acid production rate and value of upper asymptote curve) of the acid production curves for F and S strains were significantly (P titrable acidity of F and S strains were observed after the second hour of incubation. An F strain acetoin producer (Lactococcus lactis subsp. lactis 470Ch2) was selected as autochthonous starter culture for industrial Valdeteja goat cheese manufacturing.

  10. A 'Slice of Cheese'

    DEFF Research Database (Denmark)

    Holtermann, Jakob von Holderstein

    2010-01-01

    Over the last decade, theorists have persistently criticised the assumption that the International Criminal Court (ICC) can produce a noteworthy deterrent effect. Consequently, consensus has emerged that we should probably look for different ways to justify the ICC or else abandon the prestigious...

  11. The effects spicing on quality of mozzarella cheese

    Directory of Open Access Journals (Sweden)

    G. Akarca

    2016-03-01

    Full Text Available In this study, 3 different spice mixes were added just after blanching to mozzarella cheese produced by high moisture production method. The dough was kneaded and filled into to fibrous cases. After filling process, cheeses were stored for 28 days at 4 °C and 85 % of relative humidity. The following characteristics were measured: color parameters, milk acidity, total dry matter, maturation index, total aerobic mesophilic bacteria, coliform bacteria, coagulase positive staphylococci, lactic acid bacteria, species of Lactococcus bacteria, proteolytic bacteria, lipolytic bacteria and mold /yeast count were examined on 0, 5, 15,21 and 28 days after storage. Although L* (lightness and a* (redness values decreased during storage period, while moreover b* (yellowness values increased. In addition acidity, dry matter and maturation index values increased during storage. Total aerobic mesophilic bacteria, lactic acid bacteria, Lactococcus spp., lipolytic bacteria and mold/ yeast counts decreased, but proteolytic bacteria count increased.

  12. Efficient lactulose production from cheese whey using sodium carbonate.

    Science.gov (United States)

    Seo, Yeong Hwan; Park, Gwon Woo; Han, Jong-In

    2015-04-15

    An economical method of lactulose production from cheese whey was developed using sodium carbonate (Na2CO3). Three parameters such as temperature, reaction time, and Na2CO3 concentration were identified as experimental factors, and yield was selected as a response parameter. The experimental factors were optimised employing Response Surface Methodology (RSM). Maximum yield of 29.6% was obtained at reaction time of 20.41 min, Na2CO3 of 0.51% at 90 °C. To overcome this limited lactulose yield, due to the conversion of lactulose to galactose, fed batch system was applied using dried cheese whey as lactose source. By this system, limit was broken, and 15.8 g/L of lactulose is produced in hour. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Varying occurrence of extended-spectrum beta-lactamase bacteria among three produce types

    KAUST Repository

    Toh, Benjamin E. W.; Bokhari, Osama Mohammed; Kutbi, Abdullah; Haroon, Mohamed; Mantilla-Calderon, David; Zowawi, Hosam; Hong, Pei-Ying

    2017-01-01

    Three types of vegetables were sampled and evaluated over 1.5 years to determine differences in their associated bacterial isolates. Particular emphasis was placed on identifying pathogenic strains that were positive for extended spectrum beta-lactamase (ESBL). Quantitative estimates of the microbial risk associated with the ESBL-positive pathogens showed that different produce types may incur varying levels of ingestion risk. Most of the currently reported ESBL-positive bacterial isolates have been identified in nosocomial environments. However, the carriage of such drug-resistant bacteria in vegetables suggests a possible connection between our daily diet and human health.

  14. Diversity, Dynamics and Activity of Bacterial Communities during Production of an Artisanal Sicilian Cheese as Evaluated by 16S rRNA Analysis

    NARCIS (Netherlands)

    Randazzo, C.L.; Torriani, S.; Akkermans, A.D.L.; Vos, de W.M.; Vaughan, E.E.

    2002-01-01

    The diversity and dynamics of the microbial communities during the manufacturing of Ragusano cheese, an artisanal cheese produced in Sicily (Italy), were investigated by a combination of classical and culture-independent approaches. The latter included PCR, reverse transcriptase-PCR (RT-PCR), and

  15. Proteolysis and consistency of Meshanger cheese

    NARCIS (Netherlands)

    Jong, de L.

    1978-01-01

    Proteolysis in Meshanger cheese, estimated by quantitative polyacrylamide gel electrophoresis is discussed. The conversion of α s1 -casein was proportional to rennet concentration in the cheese. Changes in consistency, after a maximum, were correlated to breakdown of

  16. Lactobacillus plantarum as a Probiotic Potential from Kouzeh Cheese (Traditional Iranian Cheese) and Its Antimicrobial Activity.

    Science.gov (United States)

    Jabbari, Vahid; Khiabani, Mahmoud Sowti; Mokarram, Reza Rezaei; Hassanzadeh, Azad Mohammad; Ahmadi, Elham; Gharenaghadeh, Sasan; Karimi, Nayyer; Kafil, Hossein Samadi

    2017-06-01

    The aim of this study is to isolate and identify Lactobacillus plantarum isolates from traditional cheese, Kouzeh, and evaluate their antimicrobial activity against some food pathogens. In total, 56 lactic acid bacteria were isolated by morphological and biochemical methods, 12 of which were identified as Lactobacillus plantarum by biochemical method and 11 were confirmed by molecular method. For analyzing the antimicrobial activity of these isolates properly, diffusion method was performed. The isolates were identified by 318 bp band dedicated for L. plantarum. The isolated L. plantarum represented an inhibitory activity against four of the pathogenic bacteria and showed different inhibition halos against each other. The larger halos were observed against Staphylococcus aureus and Staphylococcus epidermidis (15 ± 0.3 and 14.8 ± 0.7 mm, respectively). The inhibition halo of Escherichia coli was smaller than that of other pathogen and some L. plantarum did not show any inhibitory activity against E. coli, which were resistant to antimicrobial compounds produced by L. plantarum. The isolated L. plantarum isolates with the antimicrobial activity in this study had strong probiotic properties. These results indicated the nutritional value of Kouzeh cheese and usage of the isolated isolates as probiotic strains.

  17. Novel Alkyd-Type Coating Resins Produced Using Cationic Polymerization [PowerPoint

    Energy Technology Data Exchange (ETDEWEB)

    Chisholm, Bret; Kalita, Harjyoti; Alam, Samim; Jayasooriyamu, Anurad; Fernando, Shashi; Samanata, Satyabrata; Bahr, James; Selvakumar, Sermadurai; Sibi, Mukund; Vold, Jessica; Ulven, Chad

    2014-04-07

    Novel, partially bio-based poly(vinyl ether) copolymers derived from soybean oil and cyclohexyl vinyl ether (CHVE) were produced by cationic polymerization and investigated for application as alkyd-type surface coatings. Compared to conventional alkyd resins, which are produced by high temperature melt condensation polymerization, the poly(vinyl ether)s provide several advantages. These advantages include miler, more energy efficient polymer synthesis, elimination of issues associated with gelation during polymer synthesis, production of polymers with well-defined composition and relatively narrow molecular weight distribution, and elimination of film formation and physical property issues associated with entrained monomers, dimers, trimmers, etc. The results of the studied showed that the thermal, mechanical, and physical properties of the coatings produced from these novel polymers varied considerable as a function of polymer composition and cure temperature. Overall, the results suggest a good potential for these novel copolymers to be used for coatings cured by autoxidation.

  18. Kinetic Behavior of on Various Cheeses under Constant and Dynamic Temperature

    Directory of Open Access Journals (Sweden)

    K. Kim

    2014-07-01

    Full Text Available In this study, we developed kinetic models to predict the growth of pathogenic Escherichia coli on cheeses during storage at constant and changing temperatures. A five-strain mixture of pathogenic E. coli was inoculated onto natural cheeses (Brie and Camembert and processed cheeses (sliced Mozzarella and sliced Cheddar at 3 to 4 log CFU/g. The inoculated cheeses were stored at 4, 10, 15, 25, and 30°C for 1 to 320 h, with a different storage time being used for each temperature. Total bacteria and E. coli cells were enumerated on tryptic soy agar and MacConkey sorbitol agar, respectively. E. coli growth data were fitted to the Baranyi model to calculate the maximum specific growth rate (μmax; log CFU/g/h, lag phase duration (LPD; h, lower asymptote (log CFU/g, and upper asymptote (log CFU/g. The kinetic parameters were then analyzed as a function of storage temperature, using the square root model, polynomial equation, and linear equation. A dynamic model was also developed for varying temperature. The model performance was evaluated against observed data, and the root mean square error (RMSE was calculated. At 4°C, E. coli cell growth was not observed on any cheese. However, E. coli growth was observed at 10°C to 30°C with a μmax of 0.01 to 1.03 log CFU/g/h, depending on the cheese. The μmax values increased as temperature increased, while LPD values decreased, and μmax and LPD values were different among the four types of cheese. The developed models showed adequate performance (RMSE = 0.176–0.337, indicating that these models should be useful for describing the growth kinetics of E. coli on various cheeses.

  19. Kinetic Behavior of Escherichia coli on Various Cheeses under Constant and Dynamic Temperature.

    Science.gov (United States)

    Kim, K; Lee, H; Gwak, E; Yoon, Y

    2014-07-01

    In this study, we developed kinetic models to predict the growth of pathogenic Escherichia coli on cheeses during storage at constant and changing temperatures. A five-strain mixture of pathogenic E. coli was inoculated onto natural cheeses (Brie and Camembert) and processed cheeses (sliced Mozzarella and sliced Cheddar) at 3 to 4 log CFU/g. The inoculated cheeses were stored at 4, 10, 15, 25, and 30°C for 1 to 320 h, with a different storage time being used for each temperature. Total bacteria and E. coli cells were enumerated on tryptic soy agar and MacConkey sorbitol agar, respectively. E. coli growth data were fitted to the Baranyi model to calculate the maximum specific growth rate (μ max; log CFU/g/h), lag phase duration (LPD; h), lower asymptote (log CFU/g), and upper asymptote (log CFU/g). The kinetic parameters were then analyzed as a function of storage temperature, using the square root model, polynomial equation, and linear equation. A dynamic model was also developed for varying temperature. The model performance was evaluated against observed data, and the root mean square error (RMSE) was calculated. At 4°C, E. coli cell growth was not observed on any cheese. However, E. coli growth was observed at 10°C to 30°C with a μ max of 0.01 to 1.03 log CFU/g/h, depending on the cheese. The μ max values increased as temperature increased, while LPD values decreased, and μ max and LPD values were different among the four types of cheese. The developed models showed adequate performance (RMSE = 0.176-0.337), indicating that these models should be useful for describing the growth kinetics of E. coli on various cheeses.

  20. Detection, Characterization and Typing of Shiga toxin-producing Escherichia coli.

    OpenAIRE

    Brendon David Parsons; Nathan eZelyas; Byron M Berenger; Linda eChui; Linda eChui

    2016-01-01

    Shiga toxin-producing Escherichia coli (STEC) are responsible for gastrointestinal diseases reported in numerous outbreaks around the world. Given the public health importance of STEC, effective detection, characterization and typing is critical to any medical laboratory system. While non-O157 serotypes account for the majority of STEC infections, frontline microbiology laboratories may only screen for STEC using O157-specific agar-based methods. As a result, non-O157 STEC infections are sign...

  1. Use of potassium chloride and flavor enhancers in low sodium Cheddar cheese.

    Science.gov (United States)

    Grummer, J; Bobowski, N; Karalus, M; Vickers, Z; Schoenfuss, T

    2013-03-01

    We investigated use of potassium chloride (KCl) to maintain both the salty flavor and to replace the preservative effects of salt when reducing the sodium content in natural cheese. Because salt replacers can affect flavor because of inherent off-flavors, such as bitter and metallic, we examined the use of flavor enhancers for their ability to modulate some of these undesirable sensory effects. Stirred-curd Cheddar-style cheese was manufactured using 2 cheese-making procedures (different curd knife sizes and target salting titratable acidities), in duplicate. Curd was salted with sodium chloride (NaCl) or 60% reduced sodium blends of NaCl and KCl (2 different sources). Curd was also salted at a 60% reduced sodium rate with NaCl and KCl with added flavor enhancers. A hydrolyzed vegetable protein/yeast extract blend, a natural "potassium-blocking type" flavor, disodium inosinate, or disodium guanylate were each blended with the reduced sodium salt blend and added to curd at the salting step. The resulting blocks of cheese were aged for 5 mo and evaluated monthly for chemical, microbial, and sensory differences. At 5 mo of aging, we measured liking for the cheeses using a consumer panel. Overall, cheeses were well liked by the consumer panel, and the scores of reduced sodium cheese with 2 different KCl sources were not different from those of the full-sodium control. The addition of flavor enhancers to Cheddar curd had mixed results, with one improving the consumer flavor liking only slightly over KCl, and one (disodium inosinate) significantly reducing consumer flavor liking scores, presumably due to the amount of umami flavor it contributed. Potassium chloride replacement salts sourced from different manufacturers affected the chemical and flavor properties of cheese, and changes to pH and temperature targets may be necessary to yield cheese with the moisture and pH targets desired. The cheese-making procedure used also influenced flavors observed, which resulted in

  2. Growth of Pseudomonas spp. in cottage cheese

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Dalgaard, Paw

    Cottage cheese is a mixture of cheese curd with pH 4.5-4.8 and an uncultured or cultured cream dressing with a pH as high as 7.0. This results in a final product with microenvironments and a bulk pH of about 4.8 to 5.5. As for other lightly preserved foods microbial contamination and growth...... of spoilage microorganisms in cottage cheese can cause undesirable alterations in flavour, odour, appearance and texture. Contamination and growth of psychrotolerant pseudomonads including Pseudomonas fragi and Pseudomonas putida has been reported for cottage cheese but the influence of these bacteria...... on product spoilage and shelf-life remains poorly described. The present study used a quantitative microbial ecology approach to model and predict the effect of product characteristics and storage conditions on growth of psychrotolerant pseudomonads in cottage cheese. The effect of temperature (5-15˚C) and p...

  3. SURVIVING OF COMMERCIAL PROBIOTIC STRAIN Lactobacillus rhamnosus GG IN SLOVAK COW LUMP CHEESE EXPERIMENTALLY INOCULATED WITH Listeria innocua

    Directory of Open Access Journals (Sweden)

    Andrea Lauková

    2014-08-01

    Full Text Available Cow lump cheese represents a traditional Slovak cheese. It belongs to fresh types of cheeses. The aim of this study was to test surviving of commercial probiotic strain Lactobacillus rhamnosus GG in cow lump cheese experimentally infected with L. innocua; (listeriae are contaminants and to check the suitability of GG strain as additive for this product. The counts of GG strain in cow lump cheeses were well balanced during whole experiment. It was found in the counts from 5.48 ± 0.15 to 7.77 ±1.50 log10 cfu/g. Its maximum in cheese was 7.77 ± 1.30 log10 cfu/g on day 7 with stability up to day 14. The identity of GG strain isolated from cheeses was confirmed by PCR. The counts of other lactic acid bacteria were also well balanced during the whole experiment in the experimental cheeses with stability up to day 14. Only in E1/GG cheese, the highest number of LAB was detected (10.60 ±1.26 log10 cfu/g. The count of L. innocua LMG 13568 was not influenced. The pH and lactic acid values were not negatively influenced. Visually, the GG cheese provided a good structure (consistency.It can be disputed that shelf-life of the product could be maintained by this way and/or the product itself with GG strain can be consumed as afunctional food or to serve as a probiotic strain carrier.

  4. 21 CFR 133.124 - Cold-pack cheese food.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Cold-pack cheese food. 133.124 Section 133.124 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD... Cheese and Related Products § 133.124 Cold-pack cheese food. (a)(1) Cold-pack cheese food is the food...

  5. Identification of human-pathogenic strains of Shiga toxin-producing Escherichia coli from food by a combination of serotyping and molecular typing of Shiga toxin genes.

    Science.gov (United States)

    Beutin, Lothar; Miko, Angelika; Krause, Gladys; Pries, Karin; Haby, Sabine; Steege, Katja; Albrecht, Nadine

    2007-08-01

    We examined 219 Shiga toxin-producing Escherichia coli (STEC) strains from meat, milk, and cheese samples collected in Germany between 2005 and 2006. All strains were investigated for their serotypes and for genetic variants of Shiga toxins 1 and 2 (Stx1 and Stx2). stx(1) or variant genes were detected in 88 (40.2%) strains and stx(2) and variants in 177 (80.8%) strains. Typing of stx genes was performed by stx-specific PCRs and by analysis of restriction fragment length polymorphisms (RFLP) of PCR products. Major genotypes of the Stx1 (stx(1), stx(1c), and stx(1d)) and the Stx2 (stx(2), stx(2d), stx(2-O118), stx(2e), and stx(2g)) families were detected, and multiple types of stx genes coexisted frequently in STEC strains. Only 1.8% of the STEC strains from food belonged to the classical enterohemorrhagic E. coli (EHEC) types O26:H11, O103:H2, and O157:H7, and only 5.0% of the STEC strains from food were positive for the eae gene, which is a virulence trait of classical EHEC. In contrast, 95 (43.4%) of the food-borne STEC strains carried stx(2) and/or mucus-activatable stx(2d) genes, an indicator for potential high virulence of STEC for humans. Most of these strains belonged to serotypes associated with severe illness in humans, such as O22:H8, O91:H21, O113:H21, O174:H2, and O174:H21. stx(2) and stx(2d) STEC strains were found frequently in milk and beef products. Other stx types were associated more frequently with pork (stx(2e)), lamb, and wildlife meat (stx(1c)). The combination of serotyping and stx genotyping was found useful for identification and for assignment of food-borne STEC to groups with potential lower and higher levels of virulence for humans.

  6. Microbial Assessment and Prevalence of Foodborne Pathogens in Natural Cheeses in Japan

    Directory of Open Access Journals (Sweden)

    Firew Kassa Esho

    2013-01-01

    Full Text Available The production and consumption of domestic natural cheese in Japan is increasing year by year. More than ninety percent of domestic natural cheese is produced in Hokkaido region of Japan, while information on its quality and safety related to foodborne pathogens is limited. To assess the microbiological safety of domestic natural cheese, a total of 126 natural cheese samples produced in Hokkaido were collected from December, 2012, to July, 2013. In addition to standard plate count (SPC and coliform counts, the prevalence study of three pathogens (Listeria monocytogenes, pathogenic Escherichia coli, and Salmonella spp. was performed on each sample. Real-time PCR and matrix-assisted laser desorption-ionization time-of-flight mass spectrometer methods were employed for identification of presumptive pathogens. Coliform was detected in 25 samples (19.8% with a minimum of 25 cfu/g and a maximum of more than 3.0 × 106 cfu/g. Salmonella spp. and L. monocytogenes were not isolated from any of the samples. Only one sample (0.80% showed positive PCR amplification for ipaH gene suggesting possible contamination of enteroinvasive E. coli or Shigella in this product. Overall results indicate that natural cheeses produced in Hokkaido region were satisfactory microbiological quality according to existing international standards.

  7. Biodiversity of Lactobacillus helveticus bacteriophages isolated from cheese whey starters.

    Science.gov (United States)

    Zago, Miriam; Bonvini, Barbara; Rossetti, Lia; Meucci, Aurora; Giraffa, Giorgio; Carminati, Domenico

    2015-05-01

    Twenty-one Lactobacillus helveticus bacteriophages, 18 isolated from different cheese whey starters and three from CNRZ collection, were phenotypically and genetically characterised. A biodiversity between phages was evidenced both by host range and molecular (RAPD-PCR) typing. A more detailed characterisation of six phages showed similar structural protein profiles and a relevant genetic biodiversity, as shown by restriction enzyme analysis of total DNA. Latent period, burst time and burst size data evidenced that phages were active and virulent. Overall, data highlighted the biodiversity of Lb. helveticus phages isolated from cheese whey starters, which were confirmed to be one of the most common phage contamination source in dairy factories. More research is required to further unravel the ecological role of Lb. helveticus phages and to evaluate their impact on the dairy fermentation processes where whey starter cultures are used.

  8. The Lactose and Galactose Content of Cheese Suitable for Galactosaemia: New Analysis.

    Science.gov (United States)

    Portnoi, P A; MacDonald, A

    2016-01-01

    The UK Medical Advisory Panel of the Galactosaemia Support Group report the lactose and galactose content of 5 brands of mature Cheddar cheese, Comte and Emmi Emmental fondue mix from 32 cheese samples. The Medical Advisory Panel define suitable cheese in galactosaemia to have a lactose and galactose content consistently below 10 mg/100 g. A total of 32 samples (5 types of mature Cheddar cheese, Comte and "Emmi Swiss Fondue", an emmental fondue mix) were analysed by high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) technology used to perform lactose and galactose analysis. Cheddar cheese types: Valley Spire West Country, Parkham, Lye Cross Vintage, Lye Cross Mature, Tesco West Country Farmhouse Extra Mature and Sainsbury's TTD West Country Farmhouse Extra Mature had a lactose and galactose content consistently below 10 mg/100 g (range <0.05 to 12.65 mg). All Comte samples had a lactose content below the lower limit of detection (<0.05 mg) with galactose content from <0.05 to 1.86 mg/100 g; all samples of Emmi Swiss Fondue had lactose below the lower limit of detection (<0.05 mg) and galactose between 2.19 and 3.04 mg/100 g. All of these cheese types were suitable for inclusion in a low galactose diet for galactosaemia. It is possible that the galactose content of cheese may change over time depending on its processing, fermentation time and packaging techniques.

  9. Sampling and farm stories prompt consumers to buy specialty cheeses

    OpenAIRE

    Reed, Barbara A.; Bruhn, Christine M.

    2003-01-01

    California specialty cheese makers need information on what drives product sales so they can effectively market their products. Focus group and telephone research revealed that specialty cheese consumers have a strong preference for sampling cheese before making a purchase. Consumers also rely heavily on staff recommendations to select cheese. They appreciate unlimited sampling in an unhurried, low-pressure environment. Specialty cheese consumers consider themselves “food experimenters”; they...

  10. The use of spices in the production of traditional cheeses

    OpenAIRE

    Renata Josipović; Ksenija Markov; Jadranka Frece; Damir Stanzer; Ante Cvitković; Jasna Mrvčić

    2016-01-01

    Cheese is a highly valued dairy product worldwide, with a special focus on traditional cheeses, not only for their basic nutritive purposes but also as a part of the culture and characteristics of a certain country. Owing to the geographical location as well as the climate and vegetation diversity, in certain regions of Croatia the production of various traditional cheeses using spices was developed. Spices are either added to the cheese curd which is then formed, or cheese is wrapped into pl...

  11. Characterization of Volatile Compounds of Bulgur (Antep Type Produced from Durum Wheat

    Directory of Open Access Journals (Sweden)

    Saad Ibrahim Yousif

    2018-01-01

    Full Text Available Bulgur is enjoyed and rediscovered by many people as a stable food because of its color, flavor, aroma, texture, and nutritional and economical values. There is more than one type of bulgur overall the world according to production techniques and raw materials. The volatile compounds of bulgur have not been explored yet. In this study, Headspace Solid Phase Microextraction (HS-SPME and Gas Chromatography–Mass Spectroscopy (GS-MS methods were used to determine the volatile flavor compounds of bulgur (Antep type, produced from Durum wheat. Approaching studies were used and the results were optimized to determine the ideal conditions for the extraction and distinguish the compounds responsible for the flavor of bulgur. Approximately, 47 and 37 important volatile compounds were determined for Durum wheat and bulgur, respectively. The study showed that there was a great diversity of volatiles in bulgur produced using Durum wheat and Antep type production method. These can lead to a better understanding of the combination of compounds that give a unique flavor with more researches.

  12. Yield and quality of brine-ripened cheeses, production from the milk of jersey and Simmental cows

    Directory of Open Access Journals (Sweden)

    Zh.T. Chitchyan

    2016-06-01

    Full Text Available Research has been conducted in Lusadzor community of Tavoush province in Armenia to determine the processability of milk samples collected from Jersey and Simmental cows for cheese manufacturing. The chemical composition as well as physical–chemical and technological parameters of the milk samples have been analyzed experimentally. In addition, the researchers estimated physical, chemical and organoleptic parameters as well as the yield of the cheese produced from the bulk milk collected from Jersey and Simmental cows. The results of the research proved that the milk samples collected from Jersey and Simmental cows possess the necessary physical–chemical and technological properties and can be used as high-quality raw material for manufacturing brine-ripened (pickled cheese. The highest content of dry matter, observed in the milk collected from Jersey cows, stemmed from the high contents of fat, protein and minerals. The content of lactose (milk sugar and physical characteristics (density, freezing temperature did not vary significantly across the samples. The rennet clots formed in the milk collected from Jersey cows were characterized by higher structural–mechanical parameters and syneresis. Jersey milk possesses the qualitative characteristics that best contribute to high cheese yield, which allows for the most efficient cheese production. Cheese manufactured from Jersey milk is distinguished by less water content, higher fat and protein contents and higher organoleptic indicators, which all together improve the quality of cheese turning it into a highly competitive product.

  13. Preliminary findings on the effect of light-oxidation on Asiago d’allevo vecchio protected designation of origin cheese

    Directory of Open Access Journals (Sweden)

    Stefania Balzan

    2013-10-01

    Full Text Available Food is exposed to light during processing, packaging, distribution and retail storage, resulting in deterioration of the product quality. Milk and other dairy products are among the most sensitive due to the high content of riboflavin, vitamin B2, which is an efficient photosensitizer for oxidative processes. Photooxidation in cheese induces degradation of nutritional quality such as proteins, lipids, and vitamins. Moreover, it causes formation of off-flavours, off-odours and gradual bleaching. The objective of this study was to evaluate the effect of light exposition on sliced Asiago d’allevo cheese (lowland vs alpine aerobically packaged stored for 336 h under both fluorescent light and in the dark. Alpine cheese showed higher b* (P<0.001 and a* indexes (P<0.001 and also a higher lipid oxidation (P<0.01 than lowland one. Riboflavin content was significantly higher (P<0.001 in lowland cheese. Cheese samples exposed to the light were significantly lighter (P<0.001 than those exposed in the dark and they also showed a decrease in yellowness (P<0.001 and redness (P<0.001 as well as in riboflavin content (P<0.001. Lipid oxidation did not produce statistically significant change. Storage time significantly affected riboflavin content (P<0.001, TBARs (P<0.001 and cheese colour (P<0.001. Results suggest that light exposition had a pronounced effect on cheese characteristics.

  14. Evaluation of quality measurement of Olomouc cake of cheese (Olomoucké tvarůžky during ripening

    Directory of Open Access Journals (Sweden)

    Daniela Strnadová

    2012-01-01

    Full Text Available Olomouc cake of cheese (Olomoucké tvarůžky is smear-ripened cheese, which is produced from sour industrial curd. Brevibacterium linens, which are added during the production process, are reproducing and make gold-yellow smear cover. The aim of this work was to assess the chemical analysis of the quality of Olomouc cake of cheese. Changes in chemical composition were evaluated during different stages of production and at the same time it was detected whether changes in chemical composition during the manufacturing process are same in spring as well as in summer, without statistically significant differences. Dry matter of Olomouc cake of cheese was ranged from 35 % to 39 %. The increase of dry matter during production is evident, but these changes were in the most cases not statistically signifiant (P > 0.05. The value of titratable acidity of the cheese considerably changes during the manufacturing process, it has a decreasing tendency. Titratable acidity of cheese after shaping was 106.64 (136.12 SH and at the end of life it was 49.91 (65.06 SH. These changes were very highly statistically significant (P 0.05 in cheese from summer period. Content of salt is increased from 5.30 % to 5.98 %, respectively 6.10 %. In spring period the oposite changes in most cases occured (P 0.05.

  15. Sequencing of the Cheese Microbiome and Its Relevance to Industry

    Directory of Open Access Journals (Sweden)

    Bhagya. R. Yeluri Jonnala

    2018-05-01

    Full Text Available The microbiota of cheese plays a key role in determining its organoleptic and other physico-chemical properties. It is essential to understand the various contributions, positive or negative, of these microbial components in order to promote the growth of desirable taxa and, thus, characteristics. The recent application of high throughput DNA sequencing (HTS facilitates an even more accurate identification of these microbes, and their functional properties, and has the potential to reveal those microbes, and associated pathways, responsible for favorable or unfavorable characteristics. This technology also facilitates a detailed analysis of the composition and functional potential of the microbiota of milk, curd, whey, mixed starters, processing environments, and how these contribute to the final cheese microbiota, and associated characteristics. Ultimately, this information can be harnessed by producers to optimize the quality, safety, and commercial value of their products. In this review we highlight a number of key studies in which HTS was employed to study the cheese microbiota, and pay particular attention to those of greatest relevance to industry.

  16. Functional properties of Mozzarella cheese for its end use application.

    Science.gov (United States)

    Ah, Jana; Tagalpallewar, Govind P

    2017-11-01

    Cheese is an extremely versatile food product that has a wide range of flavor, textures and end uses. The vast majority of cheese is eaten not by itself, but as part of another food. As an ingredient in foods, cheese is required to exhibit functional characteristics in the raw as well as cooked forms. Melting, stretching, free-oil formation, elasticity and browning are the functional properties considered to be significant for Mozzarella cheese. When a cheese is destined for its end use, some of its unique characteristics play a significant role in the products acceptability. For instance pH of cheese determines the cheese structure which in turn decides the cheese shredability and meltability properties. The residual galactose content in cheese mass determines the propensity of cheese to brown during baking. Development of 'tailor-made cheese' involves focusing on manipulation of such unique traits of cheese in order to obtain the desired characteristics for its end use application suiting the varied consumer's whims and wishes. This comprehensive review paper will provide an insight to the cheese maker regarding the factors determining the functional properties of cheese and also for the pizza manufacturers to decide which age of cheese to be used which will perform well in baking applications.

  17. Cheese whey: A cost-effective alternative for hyaluronic acid production by Streptococcus zooepidemicus.

    Science.gov (United States)

    Amado, Isabel R; Vázquez, José A; Pastrana, Lorenzo; Teixeira, José A

    2016-05-01

    This study focuses on the optimisation of cheese whey formulated media for the production of hyaluronic acid (HA) by Streptococcus zooepidemicus. Culture media containing whey (W; 2.1g/L) or whey hydrolysate (WH; 2.4 g/L) gave the highest HA productions. Both W and WH produced high yields on protein consumed, suggesting cheese whey is a good nitrogen source for S. zooepidemicus production of HA. Polysaccharide concentrations of 4.0 g/L and 3.2g/L were produced in W and WH in a further scale-up to 5L bioreactors, confirming the suitability of the low-cost nitrogen source. Cheese whey culture media provided high molecular weight (>3000 kDa) HA products. This study revealed replacing the commercial peptone by the low-cost alternative could reduce HA production costs by up to a 70% compared to synthetic media. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Prevalence of Listeria monocytogenes in European cheeses: A systematic review and meta-analysis

    DEFF Research Database (Denmark)

    Martinez Rios, Veronica; Dalgaard, Paw

    -ripened and brined) and for cheeses produced using pasteurized or un-pasteurized milk. Data from a total of 177428 samples were analysed. The mean prevalence during 2005-2013 and estimated from scientific literature (2.3%; CI: 1.4-3.8%) was more than two times higher than results from EFSA reports (0.9%; CI: 0...... not significantly different (P > 0.05) for cheeses produced from pasteurized (1.0%; CI: 0.7-1.5%) or un-pasteurized (1.4%; CI: 0.9-2.1%) milk. Furthermore, this systematic review focused on groups/species of microorganisms suitable as indicator organisms for L. monocytogenes in cheeses to reflect the level...

  19. Production optimization of probiotic soft cheese made from goat's and cow's milk

    Directory of Open Access Journals (Sweden)

    Ida Drgalić

    2006-07-01

    Full Text Available The aim of this study was to determine optimal rennet share and fat content in milk for probiotic soft cheeseproduction made from goat's and cow's milk using DVS mixed probiotic culture ABT-4 (Lactobacillus acidophilus, Bifidobacterium spp. and Streptococcus thermophilus, with desirable sensory properties, which will be acceptable by consumers. The best sensory scores had samples of probiotic soft cheese produced in laboratory conditions from milk with 1% of milk fat, pasteurized at 65°C/30 min., fermented at 38°C with 2% culture. To achieve characteristic consistency of traditional soft cheese, 0.01% of rennet was added to goat's milk. Probiotic soft cheese made from cow's and goat's milk, produced under optimal conditions, were 100% acceptable by the tested consumers.

  20. Use of cheese whey for biomass production and spray drying of probiotic lactobacilli.

    Science.gov (United States)

    Lavari, Luisina; Páez, Roxana; Cuatrin, Alejandra; Reinheimer, Jorge; Vinderola, Gabriel

    2014-08-01

    The double use of cheese whey (culture medium and thermoprotectant for spray drying of lactobacilli) was explored in this study for adding value to this wastewater. In-house formulated broth (similar to MRS) and dairy media (cheese and ricotta whey and whey permeate) were assessed for their capacity to produce biomass of Lactobacillus paracasei JP1, Lb. rhamnosus 64 and Lb. gasseri 37. Simultaneously, spray drying of cheese whey-starch solution (without lactobacilli cells) was optimised using surface response methodology. Cell suspensions of the lactobacilli, produced in in house-formulated broth, were spray-dried in cheese whey-starch solution and viability monitored throughout the storage of powders for 2 months. Lb. rhamnosus 64 was able to grow satisfactorily in at least two of the in-house formulated culture media and in the dairy media assessed. It also performed well in spray drying. The performance of the other strains was less satisfactory. The growth capacity, the resistance to spray drying in cheese whey-starch solution and the negligible lost in viability during the storage (2 months), makes Lb. rhamnosus 64 a promising candidate for further technological studies for developing a probiotic dehydrated culture for foods, utilising wastewaters of the dairy industry (as growth substrate and protectant) and spray drying (a low-cost widely-available technology).

  1. A comparative study of the fatty acid profiles in commercial sheep cheeses

    Directory of Open Access Journals (Sweden)

    Aguilar, C.

    2014-12-01

    Full Text Available The present study was carried out to characterize the FA profile of sheep cheese marketed in Chile. Fifty-eight cheeses were collected from supermarkets of 5 different Chilean cities including 34 sheep cheeses, 7 from goat’s milk, 11 from cow’s milk, 4 from a mixture of sheep, goat and cow’s milk and 2 from a mixture of sheep and cow’s milk. Compared to the cow and goat cheese (3.4 and 2.5 g·100g−1, the sheep cheese (3.8 g·100g−1 contained higher contents of C18:1t. The saturated and polyunsatured FA contents were greater in goat cheese than in sheep and cow cheese. The n6/n3 ratio was greater in goat (6.1 cheese than in sheep and cow cheese (3.8 and 5.2. The atherogenicity index was unaffected by cheese type, however, the thrombogenic index was lower in sheep cheese (2.8 than in goat and cow cheese (3.1 and 2.9. The n6/n3 ratio and thrombogenic index were lower in Chilean sheep cheese than in those imported from Europe. The fatty acid profile of cheese can be used to differentiate animal species from which the cheese is made and to some extent the geographical origin that may give some insight as to animal feed and production management.Este estudio fue llevado a cabo para caracterizar el perfil de AG de quesos de oveja que se comercializan en Chile. Cincuenta y ocho quesos fueron recogidos de supermercados de 5 ciudades de Chile de los cuales 34 fueron de oveja, 7 de cabra, 11 de vaca, 4 de mezcla de leche de oveja, cabra y vaca y 2 de mezcla de leche de oveja y vaca. Comparado con quesos de vaca y cabra (3.4 y 2.5 g·100g−1, los quesos de oveja (3.8 g·100g−1 presentaron mayor contenido de C18:1t. Los AG saturados y poliinsaturados tuvieron concentraciones más altas en los quesos de cabra que en los quesos de oveja y vaca. La relación n6/n3 fue más alta en quesos de cabra (6.1 que en quesos de oveja y vaca (3.8 y 5.2. El índice aterogénico no fue afectado por el tipo de queso, sin embargo, el índice trombogénico fue

  2. Transference of lutein during cheese making, color stability, and sensory acceptance of Prato cheese

    OpenAIRE

    Kubo, MTK; Maus, D; Xavier, AAO; Mercadante, AZ; Viotto, WH

    2013-01-01

    The consumption of lutein is associated with the prevention and reduction of age-related macular degeneration. Its incorporation into Prato cheese as a yellowish food coloring is a valid alternative to increase the daily intake of this compound. However, part of the lutein added may be lost in the whey during the cheese making, or it can be degraded by light during storage, resulting in color changes reducing the sensory acceptance of the cheese. The objectives of this study were to determine...

  3. A study on the chemical characteristics changes throughout the manufacture and ripening of Lighvan cheese

    Directory of Open Access Journals (Sweden)

    H Mirzae

    2011-08-01

    Full Text Available Lighvan cheese is one of the traditional cheeses which have the most high quantity of use in Iran. It is produced in South East of Tabriz in North West of Iran. The raw milk of ewe together with 20% -30% of goat's milk, without yeast, are used for its production. Its taste is mild salty and its scent is pleasant. The purpose of this study was to investigate the chemical indexes changes including salt percentage, the degree of acidity, pH, dry mater, ashes, and protein during the production and ripening. For this purpose, after coordinating with 10 local cheese producers, one batch from each producer and from each batch 20 tins, weighing 1 kg, which in total was 200 newly packaged cheese were purchased randomly. The tins were kept in special caves for 30 days in the region and then 60 days in refrigerator. In each batch sample of the raw milk, clot after rising and before salting, the cheese during the package time in tin and the cheese sample on 15th, 30th, 60th, and 90th days of ripining was analyzed chemically. The results of the study from the initial days of production to the end of the ripening period indicated the following changes: the rate of fat from 6.8 ± 0.25 in milk to 24.55±0.95 in samples, pH from 5.94± 0.06 in milk to 4.4±0.11 in samples, acidity from 39.4 ± 5.99 D° in milk to 119.4±5.38 in samples, rate of ash from 1.77±0.23 in milk to 8.09±2.32 in samples, the percentage of dry mater from 16.52±0.74 in milk to 43.57±1.34 in samples, and finally the percentage of protein from 4.45±1/12 in milk to 14.2±1.4 in samples. This result suggests that Lighvan cheese has unique characteristics in terms of its alteration procedure and chemical characteristics and based on the standard criterion in Iran, 2344-1, it is white cheese ripened brine in terms of chemical characteristics and fatty cheese in terms of the percentage of fat.

  4. Use of egg white protein powder based films fortified with sage and lemon balm essential oils in the storage of lor cheese

    Directory of Open Access Journals (Sweden)

    Gökhan Kavas

    2016-03-01

    Full Text Available Edible film was produced by adding 3 % sorbitol (w/v to egg white protein powder (EWPP. The first group of lor cheese samples was coated with a film fortified by sage essential oil (SEO and the second group of samples was coated with films enriched by adding lemon balm essential oil (BEO at various concentrations [0.5 %, 1 %, 2 % (v/v]. The films were labeled as EWPPSEO(0.5, EWPPSEO(1, EWPPSEO(2, EWPPBEO(0.5, EWPPBEO(1, EWPPBEO(2 to indicate the type and the concentration of the additive. The third batch of the lor cheese samples was coated exclusively with non-fortified EWPP and the fourth batch was uncoated. All of the cheese samples were artificially contaminated with Escherichia coli O157:H7 (E. coli O157:H7, Listeria monocytogenes (L. monocytogenes and Staphylococcus aureus (S. aureus. Viable cell counts of these species, yeasts and moulds were determined after the cheese production. All the samples were stored at +4 °C. Their physicochemical and microbiological properties were examined on the 1st, 7th, 15th and 30th day of the storage. Thereat significant (P0.05. Physicochemical and antibacterial properties were more significant in SEO at all concentrations compared to BEO. However, the antifungal effect of BEO was higher than that of SEO. The antifungal effect of BEO was the same at 1 % (v/v and 2 % (v/v concentrations. E. coli O157:H7 was the most resistant microorganism to the essential oils while L. monocytogenes was the most sensitive. EWPP showed a bacteriostatic effect on the microorganisms and bactericidal effects were determined on the 30th day of the storage against L. monocytogenes and yeast-moulds.

  5. THE PRODUCTION OF THE CHEESE IN SERTÃO SERGIPANO EXCHANGE OF HANDS: A MATTER OF GENDER

    Directory of Open Access Journals (Sweden)

    Sônia de Souza Mendonça MENEZES

    2008-12-01

    Full Text Available Our aim in this study is to present the changes in rural areas of the Sertão Sergipano of San Francisco under the food system, highlighting the issue of gender in the process of the production of cheese. With the inclusion of public policies were introduced new practices providing a rapid deforestation of the original vegetation caatinga. Introduce itself grasses resistant to estiagem reducing itself agricultural activities as the production of foods: beans, cassava and maize. Expands to livestock by building financial resources released by the "state" in incessant search to achieve the modernization of agriculture. Alongside the changes in the environment, changes occur in the context of social relations and cultural practices. Traditionally the family farmers had to produce milk intended for self-consumption in the form in natura or producing derivatives such as cheese and homemade butter on the responsibility of women. With the advancement of livestock this activity becomes going to be the responsibility of the males in unique spaces, there are new types of networks are built and marketing. Keywords: cultural identity, gender, livestock, public policies.

  6. Hydrogen production by Escherichia coli {delta}hycA {delta}lacI using cheese whey as substrate

    Energy Technology Data Exchange (ETDEWEB)

    Rosales-Colunga, Luis Manuel; Ordonez, Leandro G.; De Leon-Rodriguez, Antonio (Division de Biologia Molecular, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Col. Lomas 4a secc. CP 78216, San Luis Potosi, SLP. Mexico); Razo-Flores, Elias; Alatriste-Mondragon, Felipe (Division de Ciencias Ambientales, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la Presa San Jose 2055, Col. Lomas 4a secc. CP 78216, San Luis Potosi, SLP. Mexico)

    2010-01-15

    This study reports a fermentative hydrogen production by Escherichia coli using cheese whey as substrate. To improve the biohydrogen production, an E. coli {delta}hycA {delta}lacI strain (WDHL) was constructed. The absence of hycA and lacI genes had a positive effect on the biohydrogen production. The strain produced 22% more biohydrogen in a shorter time than the wild-type (WT) strain. A Box-Behnken experimental design was used to optimize pH, temperature and substrate concentration. The optimal initial conditions for biohydrogen production by WDHL strain were pH 7.5, 37 C and 20 g/L of cheese whey. The specific production rate was improved from 3.29 mL H{sub 2}/optical density at 600 nm (OD{sub 600nm}) unit-h produced by WDHL under non-optimal conditions to 5.88 mL H{sub 2}/OD{sub 600nm} unit-h under optimal conditions. Using optimal initial conditions, galactose can be metabolized by WDHL strain. The maximum yield obtained was 2.74 mol H{sub 2}/mol lactose consumed, which is comparable with the yield reached in other hydrogen production processes with Clostridium sp. or mixed cultures. (author)

  7. Characterization of microflora in Latin-style cheeses by next-generation sequencing technology

    Directory of Open Access Journals (Sweden)

    Lusk Tina S

    2012-11-01

    Full Text Available Abstract Background Cheese contamination can occur at numerous stages in the manufacturing process including the use of improperly pasteurized or raw milk. Of concern is the potential contamination by Listeria monocytogenes and other pathogenic bacteria that find the high moisture levels and moderate pH of popular Latin-style cheeses like queso fresco a hospitable environment. In the investigation of a foodborne outbreak, samples typically undergo enrichment in broth for 24 hours followed by selective agar plating to isolate bacterial colonies for confirmatory testing. The broth enrichment step may also enable background microflora to proliferate, which can confound subsequent analysis if not inhibited by effective broth or agar additives. We used 16S rRNA gene sequencing to provide a preliminary survey of bacterial species associated with three brands of Latin-style cheeses after 24-hour broth enrichment. Results Brand A showed a greater diversity than the other two cheese brands (Brands B and C at nearly every taxonomic level except phylum. Brand B showed the least diversity and was dominated by a single bacterial taxon, Exiguobacterium, not previously reported in cheese. This genus was also found in Brand C, although Lactococcus was prominent, an expected finding since this bacteria belongs to the group of lactic acid bacteria (LAB commonly found in fermented foods. Conclusions The contrasting diversity observed in Latin-style cheese was surprising, demonstrating that despite similarity of cheese type, raw materials and cheese making conditions appear to play a critical role in the microflora composition of the final product. The high bacterial diversity associated with Brand A suggests it may have been prepared with raw materials of high bacterial diversity or influenced by the ecology of the processing environment. Additionally, the presence of Exiguobacterium in high proportions (96% in Brand B and, to a lesser extent, Brand C (46%, may

  8. Equilibrium moisture content of OSB panels produced with veneer inclusion and different types of adhesive

    Directory of Open Access Journals (Sweden)

    Lourival Marin Mendes

    2014-03-01

    Full Text Available The aim of this study was to evaluate different statistical models to estimate the equilibrium moisture content of OSB panels exposed to different conditions of air temperature and relative humidity, And also to evaluate the influence of the adhesive and veneer inclusion in the equilibrium moisture content. The panels were produced with three different adhesive types (phenol-formaldehyde - FF, melamine-urea-formaldehyde - MUF, and phenol-melamine-urea-formaldehyde - PMUF and with and without veneer inclusion. The evaluation of the equilibrium moisture content of the panels was carried out at temperatures of 30, 40 and 50°C and relative humidity of 40, 50, 60, 70, 80 and 90%. The modeling of equilibrium moisture content was performed using the statistical non-linear and polynomial models. In general, the polynomial models are most indicated for determining the equilibrium moisture content of OSB. The models adjusted only with air relative humidity presented the best precision measurements. The type of adhesive affected the equilibrium moisture content of the panels, being observed for adhesives PMUF and FF the same trend of variation, and the highest values obtained for the panels produced with adhesive MUF. The veneer inclusion decreased the equilibrium moisture content only in the panels with MUF adhesive.

  9. Use of various types of carbon-containing raw materials to produce thermal energy

    Directory of Open Access Journals (Sweden)

    В. Б. Кусков

    2016-08-01

    Full Text Available Many types of carbon-containing organic compounds and all possible carbon-containing products or wastes in low demand can be used to produce thermal energy. A technology has been developed for producing highly flammable briquettes on the basis of bituminous coal. These briquettes have a special incendiary layer. It is easily ignites from low energy heat sources (e.g. matches, and then flame spreads to the rest of briquette. Use of coal slacks and paper wastes as carbon-containing components playing the role of binders provides an opportunity to get a fuel briquette easy in terms of production and plain in composition while at the same time dispose of coal and paper wastes. Such briquettes may also have a special incendiary layer. Technology for fuel briquettes production from wood and slate wastes employed no binding agents, as wood products acted as binders. Thus technologies have been developed to produce fuel briquettes from various carbon-containing materials in low demand. The briquettes are intended for household boilers, fireplaces, different ovens in order to cook food, heat residential and utility premises, cabins, etc.

  10. Breed of cow and herd productivity affect milk nutrient recovery in curd, and cheese yield, efficiency and daily production.

    Science.gov (United States)

    Stocco, G; Cipolat-Gotet, C; Gasparotto, V; Cecchinato, A; Bittante, G

    2018-02-01

    Little is known about cheese-making efficiency at the individual cow level, so our objective was to study the effects of herd productivity, individual herd within productivity class and breed of cow within herd by producing, then analyzing, 508 model cheeses from the milk of 508 cows of six different breeds reared in 41 multi-breed herds classified into two productivity classes (high v. low). For each cow we obtained six milk composition traits; four milk nutrient (fat, protein, solids and energy) recovery traits (REC) in curd; three actual % cheese yield traits (%CY); two theoretical %CYs (fresh cheese and cheese solids) calculated from milk composition; two overall cheese-making efficiencies (% ratio of actual to theoretical %CYs); daily milk yield (dMY); and three actual daily cheese yield traits (dCY). The aforementioned phenotypes were analyzed using a mixed model which included the fixed effects of herd productivity, parity, days in milk (DIM) and breed; the random effects were the water bath, vat, herd and residual. Cows reared in high-productivity herds yielded more milk with higher nutrient contents and more cheese per day, had greater theoretical %CY, and lower cheese-making efficiency than low-productivity herds, but there were no differences between them in terms of REC traits. Individual herd within productivity class was an intermediate source of total variation in REC, %CY and efficiency traits (10.0% to 17.2%), and a major source of variation in milk yield and dCY traits (43.1% to 46.3%). Parity of cows was an important source of variation for productivity traits, whereas DIM affected almost all traits. Breed within herd greatly affected all traits. Holsteins produced more milk, but Brown Swiss cows produced milk with higher actual and theoretical %CYs and cheese-making efficiency, so that the two large-framed breeds had the same dCY. Compared with the two large-framed breeds, the small Jersey cows produced much less milk, but with greater actual

  11. Friction produced by types of elastomeric ligatures in treatment mechanics with the preadjusted appliance.

    Science.gov (United States)

    Baccetti, Tiziano; Franchi, Lorenzo

    2006-03-01

    The objective was to compare the frictional forces generated by new nonconventional passive elastomeric ligatures (NCL) and conventional elastomeric ligatures (CL) under dry conditions. An experimental model reproducing the right buccal segment of the upper arch and consisting of five stainless steel 0.022-inch preadjusted brackets (from the second premolar through the central incisor) was used to assess both static and kinetic frictional forces produced by NCL and CL. The frictional forces generated by the 0.019 x 0.025-inch stainless steel wire with the two types of elastomeric ligatures were recorded by sliding the wire into the aligned brackets. The friction produced by the 0.014-inch superelastic nickel titanium wire was evaluated both in the presence of aligned brackets and of three-mm misaligned canine bracket. The amount of both static and kinetic frictions were minimal (<10 g) in the NCL group in the presence of aligned brackets with both types of wires, whereas it ranged from a minimum of 95.6 g for the 0.014-inch superelastic nickel titanium wire to a maximum of 590.7 g for the 0.019 x 0.025-inch stainless steel wire when using CL. The amount of both static and kinetic frictions in the presence of a misaligned canine bracket in the NCL group were less than half of that shown by the CL group. A recently developed passive ligature system is able to produce significantly lower levels of frictional forces in vitro when compared with conventional elastomeric modules.

  12. Improved traceability of Shiga-toxin-producing Escherichia coli using CRISPRs for detection and typing.

    Science.gov (United States)

    Delannoy, Sabine; Beutin, Lothar; Fach, Patrick

    2016-05-01

    Among strains of Shiga-toxin-producing Escherichia coli (STEC), seven serogroups (O26, O45, O103, O111, O121, O145, and O157) are frequently associated with severe clinical illness in humans. The development of methods for their reliable detection from complex samples such as food has been challenging thus far, and is currently based on the PCR detection of the major virulence genes stx1, stx2, and eae, and O-serogroup-specific genes. However, this approach lacks resolution. Moreover, new STEC serotypes are continuously emerging worldwide. For example, in May 2011, strains belonging to the hitherto rarely detected STEC serotype O104:H4 were identified as causative agents of one of the world's largest outbreak of disease with a high incidence of hemorrhagic colitis and hemolytic uremic syndrome in the infected patients. Discriminant typing of pathogens is crucial for epidemiological surveillance and investigations of outbreaks, and especially for tracking and tracing in case of accidental and deliberate contamination of food and water samples. Clustered regularly interspaced short palindromic repeats (CRISPRs) are composed of short, highly conserved DNA repeats separated by unique sequences of similar length. This distinctive sequence signature of CRISPRs can be used for strain typing in several bacterial species including STEC. This review discusses how CRISPRs have recently been used for STEC identification and typing.

  13. Effect of commercial grape extracts on the cheese-making properties of milk.

    Science.gov (United States)

    Felix da Silva, Denise; Matumoto-Pintro, Paula T; Bazinet, Laurent; Couillard, Charles; Britten, Michel

    2015-03-01

    Grape extracts can be added to milk to produce cheese with a high concentration of polyphenols. Four commercial extracts from whole grape, grape seed, and grape skin (2 extracts) were characterized and added to milk at concentrations of 0, 0.1, 0.2, and 0.3% (wt/vol). The effect of grape extracts on the kinetics of milk clotting, milk gel texture, and syneresis were determined, and model cheeses were produced. Whole grape and grape seed extracts contained a similar concentration of polyphenolic compounds and about twice the amount found in grape skin extracts. Radical scavenging activity was directly proportional to the phenolic compounds content. When added to milk, grape extracts increased rennet-induced clotting time and decreased the clotting rate. Although differences were observed between the extracts, the concentration added to milk was the main factor influencing clotting properties. With increasing concentrations of grape extracts, milk gels showed increased brittleness and reduced firmness. In addition, syneresis of milk gels decreased with increasing concentrations of grape extracts, which resulted in cheeses with a higher moisture content. The presence of grape extracts in milk slightly increased protein recovery in cheese but had no effect on fat recovery. With whole grape or grape seed extracts added to milk at 0.1% (wt/vol), the recovery coefficient for polyphenols was about 0.63, and decreased with increasing extract concentration in milk. Better polyphenol recovery was observed for grape seed extracts (0.87), with no concentration effect. Commercial extracts from whole grape, grape seed, or grape skin can be added to milk in the 0.1 to 0.3% (wt/vol) concentration range to produce cheese with potential health benefits, without a negative effect on cheese yield. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  14. Discriminating aging and protein-to-fat ratio in Cheddar cheese using sensory analysis and a potentiometric electronic tongue.

    Science.gov (United States)

    Lipkowitz, Jackie B; Ross, Carolyn F; Diako, Charles; Smith, Denise M

    2018-03-01

    The objectives of this study were to evaluate the flavor and taste attributes of full-fat Cheddar cheeses with different protein-to-fat ratios (PFR) over aging time using a descriptive sensory analysis panel and a consumer panel, and to correlate these attributes with instrumental parameters obtained by the potentiometric electronic tongue. Three Cheddar cheese formulations (PFR of 0.74, 0.85, and 1.01) were produced in triplicate and composition was verified. Cheese was aged at 7.2°C and evaluated at 2, 5, 8, 10, 11, and 12 mo by a trained panel (n = 10) for 8 flavor and 5 taste attributes and using an electronic tongue for 7 nonvolatile taste attributes. Cheese aged for 12 mo was also evaluated by a consumer sensory panel for liking and intensity attributes. Principal component analysis was performed to discriminate cheese based on aging time and PFR, whereas correlation between sensory and instrumental attributes was assessed using partial least squares regression. Descriptive sensory analysis of flavor and taste attributes differentiated Cheddar cheeses over aging time, but not among PFR formulations. The electronic tongue distinguished changes among cheese samples due to PFR formulation and aging time. The electronic tongue proved successful in characterizing the nonvolatile flavor components in Cheddar cheese and correlated with taste perceptions measured by descriptive sensory analysis. Consumer evaluations showed distinctive attribute profiles for the 3 PFR Cheddar cheese formulations. Overall, higher fat content was associated with increased flavor intensities in Cheddar cheese and drove consumer acceptability and purchase intent ratings. The electronic tongue detected smaller changes in tastes (bitter, metallic, salty, sour, spicy, sweet, and umami) of the 3 PFR formulations over time when compared with the trained panelists, who detected no differences, suggesting that the electronic tongue may be more sensitive to tastants than humans and may have the

  15. Impact of vitamin E and selenium on antioxidant capacity and lipid oxidation of cheddar cheese in accelerated ripening.

    Science.gov (United States)

    Batool, Maryam; Nadeem, Muhammad; Imran, Muhammad; Gulzar, Nabila; Shahid, Muhammad Qamar; Shahbaz, Muhammad; Ajmal, Muhammad; Khan, Imran Taj

    2018-04-11

    protein content of cheddar cheese. After 6 weeks of ripening, total antioxidant capacity of T 1 , T 2 , T 3 , T 4 , T 5 , T 6 , T 7 and standard cheese were 29.61%, 44.7%, 53.6%, 42.5%, 41.4%, 64.1%, 85.1% and 25.4%. After 6 weeks of ripening, reducing power of T 1 , T 2 , T 3 , T 4 , T 5 , T 6 , T 7 and SC cheese were 14.7%, 18.1%, 26.3%, 19.2%, 25.3%, 33.4%, 40.3% and 11.6%. After 6 weeks of ripening, 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of T 6 and T 7 were 54.2% and 66.9%. While, DPPH free radical scavenging activity of T 1 and standard cheese after 6 weeks of ripening were, 19.1 and 18.5%, respectively. Free fatty acids of vitamin E and selenium supplemented, non-supplemented and standard cheese were not significantly influenced from each other in 0, 6 and 12 weeks old cheddar cheese. Peroxide values of T 1 , T 2 , T 3 , T 4 , T 5 , T 6 , T 7 and standard cheese after 6 weeks of accelerated ripening were 1.19, 1.05, 0.88, 1.25, 0.29, 0.25, 0.24 and 0.28 (MeqO 2 /kg). After 6 weeks of ripening, anisidine value of T 6 and T 7 were 6.55 and 6.14. Conjugated dienes of T 1 , T 2 , T 3 , T 4 , T 5 , T 6 , T 7 and standard cheese, after 6 weeks of accelerated ripening were 0.61, 0.55, 0.42, 0.77, 0.65, 0.17, 0.15 and 0.19. After 6 weeks of accelerated ripening, concentrations unsaturated fatty acids in T 1 , T 2 , T 3 , T 4 , T 5 , T 6 , T 7 and standard cheese decreased by18.19%, 17.45%, 16.82%, 16.19%, 12.71%, 8.48%, 6.92% and 14.71%. After 12 weeks of accelerated ripening, concentration of unsaturated fatty acids in T 1 , T 2 , T 3 , T 4 , T 5 , T 6 and T 7 and standard cheese decreased by 26.2%, 21.2%, 18.7%, 14.2%, 10.4%, 4.84%, 1.03% and 6.78%. Cheddar cheese samples added with vitamin E, selenium and their combinations produced more organic acids during the ripening period of 12 weeks. After 6 and 12 weeks of ripening, flavor score of T 6 and T 7 was better than standard ripened cheddar cheese. After 6 weeks of

  16. Detection, Characterization, and Typing of Shiga Toxin-Producing Escherichia coli.

    Science.gov (United States)

    Parsons, Brendon D; Zelyas, Nathan; Berenger, Byron M; Chui, Linda

    2016-01-01

    Shiga toxin-producing Escherichia coli (STEC) are responsible for gastrointestinal diseases reported in numerous outbreaks around the world. Given the public health importance of STEC, effective detection, characterization and typing is critical to any medical laboratory system. While non-O157 serotypes account for the majority of STEC infections, frontline microbiology laboratories may only screen for STEC using O157-specific agar-based methods. As a result, non-O157 STEC infections are significantly under-reported. This review discusses recent advances on the detection, characterization and typing of STEC with emphasis on work performed at the Alberta Provincial Laboratory for Public Health (ProvLab). Candidates for the detection of all STEC serotypes include chromogenic agars, enzyme immunoassays (EIA) and quantitative real time polymerase chain reaction (qPCR). Culture methods allow further characterization of isolates, whereas qPCR provides the greatest sensitivity and specificity, followed by EIA. The virulence gene profiles using PCR arrays and stx gene subtypes can subsequently be determined. Different non-O157 serotypes exhibit markedly different virulence gene profiles and a greater prevalence of stx1 than stx2 subtypes compared to O157:H7 isolates. Finally, recent innovations in whole genome sequencing (WGS) have allowed it to emerge as a candidate for the characterization and typing of STEC in diagnostic surveillance isolates. Methods of whole genome analysis such as single nucleotide polymorphisms and k-mer analysis are concordant with epidemiological data and standard typing methods, such as pulsed-field gel electrophoresis and multiple-locus variable number tandem repeat analysis while offering additional strain differentiation. Together these findings highlight improved strategies for STEC detection using currently available systems and the development of novel approaches for future surveillance.

  17. Detection, Characterization and Typing of Shiga toxin-producing Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Brendon David Parsons

    2016-04-01

    Full Text Available Shiga toxin-producing Escherichia coli (STEC are responsible for gastrointestinal diseases reported in numerous outbreaks around the world. Given the public health importance of STEC, effective detection, characterization and typing is critical to any medical laboratory system. While non-O157 serotypes account for the majority of STEC infections, frontline microbiology laboratories may only screen for STEC using O157-specific agar-based methods. As a result, non-O157 STEC infections are significantly under-reported. This review discusses recent advances on the detection, characterization and typing of STEC with emphasis on work performed at the Alberta Provincial Laboratory for Public Health (ProvLab. Candidates for the detection of all STEC serotypes include chromogenic agars, enzyme immunoassays (EIA and real-time polymerase chain reaction (qPCR. Culture methods allow further characterization of isolates, whereas qPCR provides the greatest sensitivity and specificity, followed by EIA. The virulence gene profiles using PCR arrays and stx gene subtypes can subsequently be determined. Different non-O157 serotypes exhibit markedly different virulence gene profiles and a greater prevalence of stx1 than stx2 subtypes compared to O157:H7 isolates. Finally, recent innovations in whole genome sequencing (WGS have allowed it to emerge as a candidate for the characterization and typing of STEC in diagnostic surveillance isolates. Methods of whole genome analysis such as single nucleotide polymorphisms and k-mer analysis are concordant with epidemiological data and standard typing methods, such as pulsed-field gel electrophoresis and multiple-locus variable number tandem repeat analysis while offering additional strain differentiation. Together these findings highlight improved strategies for STEC detection using currently available systems and the development of novel approaches for future surveillance.

  18. Biotechnological Utilization with a Focus on Anaerobic Treatment of Cheese Whey: Current Status and Prospects

    Directory of Open Access Journals (Sweden)

    Aspasia A. Chatzipaschali

    2012-09-01

    Full Text Available Cheese whey utilization is of major concern nowadays. Its high organic matter content, in combination with the high volumes produced and limited treatment options make cheese whey a serious environmental problem. However, the potential production of biogas (methane, hydrogen or other marketable products with a simultaneous high COD reduction through appropriate treatment proves that cheese whey must be considered as an energy resource rather than a pollutant. The presence of biodegradable components in the cheese whey coupled with the advantages of anaerobic digestion processes over other treatment methods makes anaerobic digestion an attractive and suitable treatment option. This paper intends to review the most representative applications of anaerobic treatment of cheese whey currently being exploited and under research. Moreover, an effort has been made to categorize the common characteristics of the various research efforts and find a comparative basis, as far as their results are concerned. In addition, a number of dairy industries already using such anaerobic digestion systems are presented.

  19. Rapid assessment of selected free amino acids during Edam cheese ripening by near infrared spectroscopy

    Directory of Open Access Journals (Sweden)

    Jiří Mlček

    2013-01-01

    Full Text Available The study focuses on rapid determination of free amino acids produced during the ripening of cheese, by using near infrared spectroscopy. Analyses of 96 samples of Edam cheese (30% and 45% of fat in dry matter were performed at monthly intervals up to the ripening age of 6 months. In total, 19 amino acids were analysed with infrared spectrometer using two different methods, either in the regime of reflectance in the integrating sphere of the apparatus or using a fibre optic apparatus with the fibre optic probe. Reference data based on high-performance liquid chromatography were used for calibration of the spectrophotometer. Calibration models were developed using a partial least square algorithm and tested by means of cross-validation. When measured with the integrating sphere and with the probe, the values of correlation coefficients ranged from 0.835 to 0.993 and from 0.739 to 0.995, respectively. Paired t-test did not show significant differences between the reference and predicted values (P < 0.05. The results of this new calibration method showed the possibility of near infrared technology for fast determination of free amino acids, which occur during the ripening of Edam cheese. The content of free amino acids allow us to prepare Edam cheese quickly and efficiently for sale or to prepare the material for processed cheese.

  20. "A little information excites us." Consumer sensory experience of Vermont artisan cheese as active practice.

    Science.gov (United States)

    Lahne, Jacob; Trubek, Amy B

    2014-07-01

    This research is concerned with explaining consumer preference for Vermont artisan cheese and the relationship between that preference and sensory experience. Artisan cheesemaking is increasingly an important part of Vermont's dairy sector, and this tracks a growing trend of artisan agricultural practice in the United States. In popular discourse and academic research into products like artisan cheese, consumers explain their preferences in terms of intrinsic sensory and extrinsic - supposedly nonsensory - food qualities. In laboratory sensory studies, however, the relationship between preference, intrinsic, and extrinsic qualities changes or disappears. In contrast, this study explains this relationship by adopting a social theory of sensory perception as a practice in everyday life. This theory is applied to a series of focus group interviews with Vermont artisan cheese consumers about their everyday perceptions. Based on the data, a conceptual framework for the sensory perception of Vermont artisan cheese is suggested: consumers combine information about producer practice, social context, and the materiality of the product through an active, learned practice of sensory perception. Particular qualities that drive consumer sensory experience and preference are identified from the interview data. Many of these qualities are difficult to categorize as entirely intrinsic or extrinsic, highlighting the need for developing new approaches of sensory evaluation in order to fully capture everyday consumer sensory perception. Thus, this research demonstrates that social theory provides new and valuable insights into consumer sensory preference for Vermont artisan cheese. Copyright © 2014 Elsevier Ltd. All rights reserved.

  1. Whey cheese: membrane technology to increase yields.

    Science.gov (United States)

    Riera, Francisco; González, Pablo; Muro, Claudia

    2016-02-01

    Sweet cheese whey has been used to obtain whey cheese without the addition of milk. Pre-treated whey was concentrated by nanofiltration (NF) at different concentration ratios (2, 2.5 and 2.8) or by reverse osmosis (RO) (2-3 times). After the concentration, whey was acidified with lactic acid until a final pH of 4.6-4.8, and heated to temperatures between 85 and 90 °C. The coagulated fraction (supernatant) was collected and freely drained over 4 h. The cheese-whey yield and protein, fat, lactose and ash recoveries in the final product were calculated. The membrane pre-concentration step caused an increase in the whey-cheese yield. The final composition of products was compared with traditional cheese-whey manufacture products (without membrane concentration). Final cheese yields found were to be between 5 and 19.6%, which are higher than those achieved using the traditional 'Requesón' process.

  2. Crystallization and preliminary crystallographic analysis of an octaketide-producing plant type III polyketide synthase

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Hiroyuki [Mitsubishi Kagaku Institute of Life Sciences (MITILS), 11 Minamiooya, Machida, Tokyo 194-8511 (Japan); Kondo, Shin; Kato, Ryohei [Innovation Center Yokohama, Mitsubishi Chemical Corporation, 1000 Kamoshida, Aoba, Yokohama, Kanagawa 227-8502 (Japan); Wanibuchi, Kiyofumi; Noguchi, Hiroshi [School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8526 (Japan); Sugio, Shigetoshi, E-mail: sugio.shigetoshi@mw.m-kagaku.co.jp [Innovation Center Yokohama, Mitsubishi Chemical Corporation, 1000 Kamoshida, Aoba, Yokohama, Kanagawa 227-8502 (Japan); Abe, Ikuro, E-mail: sugio.shigetoshi@mw.m-kagaku.co.jp [School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka 422-8526 (Japan); PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Kohno, Toshiyuki, E-mail: sugio.shigetoshi@mw.m-kagaku.co.jp [Mitsubishi Kagaku Institute of Life Sciences (MITILS), 11 Minamiooya, Machida, Tokyo 194-8511 (Japan)

    2007-11-01

    Octaketide synthase from A. arborescens has been overexpressed in E. coli, purified and crystallized. Diffraction data have been collected to 2.6 Å. Octaketide synthase (OKS) from Aloe arborescens is a plant-specific type III polyketide synthase that produces SEK4 and SEK4b from eight molecules of malonyl-CoA. Recombinant OKS expressed in Escherichia coli was crystallized by the hanging-drop vapour-diffusion method. The crystals belonged to space group I422, with unit-cell parameters a = b = 110.2, c = 281.4 Å, α = β = γ = 90.0°. Diffraction data were collected to 2.6 Å resolution using synchrotron radiation at BL24XU of SPring-8.

  3. A new type of EPR experiment using light quanta produced by nonlinear optical process

    International Nuclear Information System (INIS)

    Shih, Y.H.; Alley, C.O.

    1989-01-01

    A pair of correlated light quanta of 532 nm wavelength with the same linear polarization but divergent directions of propagation was produced by non-linear optical parametric down conversion in a crystal of deuterated potassium di-hydrogen phosphate from a 100 ps duration laser pulse of 266 nm wavelength. Each light quantum was converted to a circular polarization state or a linear polarization state (orthogonal) and was reflected by a turning mirror to superpose with the other at a beam splitter to produce a two-quanta superposition state. For coincident detection of the two light quanta at separated detectors, correlations of the Einstein-Podolsky-Rosen type for the polarizations have been observed as predicted by our analysis. In preliminary runs with limited data we have measured a violation of Bell's inequality by three standard deviations. We are planning to extend our experiments to include a truly random delayed choice between two analyser settings at each detector while maintaining a spacelike separation between the detections. (orig.)

  4. Functional analysis of truncated and site-directed mutagenesis dextransucrases to produce different type dextrans.

    Science.gov (United States)

    Wang, Chao; Zhang, Hong-Bin; Li, Meng-Qi; Hu, Xue-Qin; Li, Yao

    2017-07-01

    Dextrans with distinct molecular size and structure are increasingly being used in the food and pharmaceutical industries. Dextran is produced by dextransucrase (DSR, EC2.4.5.1), which is produced by Leuconostoc mesenteroides. DSR belongs to glycosyl hydrolase family (GH70) and synthesizes branched α-glucan (dextran) with both 5% α(1-3) and 95% α(1-6) glycosidic linkages. The DSR gene dex-YG (Genebank, Accession No. DQ345760) was cloned from the wild strain Leuconostoc mesenteroides 0326. This study generated a series of C-terminally truncated variants of dextransucrase and substituting the amino-acid residues in the active site of DSR. With shorter length of DSR, its polysaccharide-synthesizing capability was impaired heavily, whereas oligosaccharide (acting as prebiotics)-synthesizing capability increased significantly, efficiently producing special sizes of dextran. All truncated mutant enzymes were active. Results demonstrated that the catalytic domain dextransucrase was likely in 800 aa or less. Based on the three-dimensional structure model of dextransucrase built through homology modeling methods, the DSR and its mutants with the acceptor substrate of maltose and donor substrate of sucrose were studied by molecular-docking method. Substituting these amino-acid residues significantly affected enzyme activities. Compared with the wild-type dextran, mutant enzymes catalyzed the synthesis of a-glucan with 1-9% α(1-3) and 90-98% α(1-6) branching linkages. Some mutants introduced a small amount of α(1-4) linkages and α(1-2) linkages. This strategy can be effectively used for the rational protein design of dextransucrase. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Application of common packaging materials in the probiotic fresh cheese production

    Directory of Open Access Journals (Sweden)

    Mirela Iličić

    2016-03-01

    Full Text Available The aim of this work was to investigate the application of common packaging materials polypropylene (PP and polystyrene (PS in the probiotic fresh cheese production packaging. Probiotic and traditional cheeses were produced from milk with standardized milk fat content of 2.3 g/100 g including the application of two cultures (probiotic and traditional. The samples were packed in the PP and PS cups and stored at 4 ºC for 30 days. The observed permeability of gases through the two applied packaging materials was significantly different. Cheese samples were analysed for microbiological properties whereby lactic acid bacteria, Bifidobacterium sp. and aerobic mesophilic bacteria (AMB were determined. Packaging materials showed no significant effect on the content of ascorbic acid which is known to be sensitive to the presence of oxygen.

  6. A high-throughput cheese manufacturing model for effective cheese starter culture screening

    NARCIS (Netherlands)

    Bachmann, H.; Kruijswijk, Z.; Molenaar, D.; Kleerebezem, M.; Hylckama Vlieg, van J.E.T.

    2009-01-01

    Cheese making is a process in which enzymatic coagulation of milk is followed by protein separation, carbohydrate removal, and an extended bacterial fermentation. The number of variables in this complex process that influence cheese quality is so large that the developments of new manufacturing

  7. Compressibility and resiliency properties of wilton type woven carpets produced with different fiber blend ratio

    Science.gov (United States)

    Osman, B.; Esin, S.; Sıdıka Ziba, O.

    2017-10-01

    Carpet is a textile structure that composed of three components: warp (stuffer and chain warp), weft and pile yarns. These textile products are used for areas which will stand up to the use of home, hotel, work place etc. Furthermore, the capable of carpets are related to it’s especially pile performance during use in various areas. During usage, carpets made from various type of raw materials of pile yarn also acts differently that these differentiate determines carpet performance, as well.This study was focused on the compression and resilience behaviour of carpet composed of 100% viscose and 100% acrylic pile yarns and blended pile yarns of blend ratios, 80%/20%, 50%/50% and 20%/80% viscose/acrylic. During the yarn production process, all spinning conditions were kept constant in order to eliminate the yarn production parameters. Five different types of wilton face to face carpet samples were produced from these yarns at the same pile height and pile density on Van de Wiele carpet weaving machine at 110 picks/min machine speed and 1/1 V carpet construction. Compressibility properties of carpets were examined whether blend ratio was statistically significant on carpet resilience or not. The behaviour of pile yarns under pressure is important that leads to understand the growth characteristic which is exposed to decrease and increase loadings during usage of carpet made from these yarns. Results indicated that blend ratio of pile yarns have significance effect on compression behaviour of carpet samples.

  8. Redox regulation of stress signals: possible roles of dendritic stellate TRX producer cells (DST cell types).

    Science.gov (United States)

    Yodoi, Junji; Nakamura, Hajime; Masutani, Hiroshi

    2002-01-01

    Thioredoxin (TRX) is a 12 kDa protein with redox-active dithiol (Cys-Gly-Pro-Cys) in the active site. TRX is induced by a variety of stresses including viral infection and inflammation. The promoter sequences of the TRX gene contain a series of stress-responsive elements including ORE, ARE, XRE, CRE and SP-1. TRX promotes DNA binding of transcription factors such as NF-kappaB, AP-1 and p53. TRX interacts with target proteins modulating the activity of those proteins. We have identified TRX binding protein-2 (TBP-2), which was identical to vitamin D3 up-regulated protein 1 (VDUP1). Potential action of TBP-2/VDUP1 as a redox-sensitive tumor suppressor will be discussed. There is accumulating evidence for the involvement of TRX in the protection against infectious and inflammatory disorders. We will discuss the role of TRX-dependent redox regulation of the host defense mechanism, in particular its relation to the emerging concept of constitutive and/or inducible TRX on special cell types with dendritic and stellate morphology in the immune, endocrine and nervous systems, which we provisionally designate as dendritic stellate TRX producer cells (DST cell types).

  9. 21 CFR 133.136 - Washed curd and soaked curd cheese.

    Science.gov (United States)

    2010-04-01

    ... Section 133.136 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... this section or by any other procedure which produces a finished cheese having the same physical and... bacterial culture. One or more of the clotting enzymes specified in paragraph (b)(2) of this section is...

  10. 21 CFR 133.156 - Low-moisture mozzarella and scamorza cheese.

    Science.gov (United States)

    2010-04-01

    ....156 Section 133.156 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... this section, or by any other procedure which produces a finished cheese having the same physical and... bacterial culture. One or more of the clotting enzymes specified in paragraph (b)(2) of this action is added...

  11. Biogenic amines degradation by microorganisms isolated from cheese

    Directory of Open Access Journals (Sweden)

    Irena Butor

    2017-01-01

    Full Text Available The aim of this study was the isolation and characterization of microorganisms able to degrade biogenic amines and their identification. Individual microorganisms were obtained by isolation from commercially available foodstuffs and food produced in the technological laboratories of Faculty of Technology, Tomas Bata University in Zlín and subsequently identified by MALDI-TOF MS. The results of MALDI-TOF MS identification were verified by 16S rRNA sequenation. In this work was studied the ability of 5 bacterial strains positive to biogenic amines degradation isolated from dairy products to decrease biogenic amines content in vitro and quantified reduction in the concentration of biogenic amines tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine and tyramine. The level of degradation (decrease of biogenic amines was determined on the base of the ability to grow in media with biogenic amines as the sole source carbon and nitrogen. The isolated strains with the ability of degradation of one or more biogenic amines were cultured in medium supplemented with relevant biogenic amines, the media derivatized with dansyl chloride and these amines separated by HPLC at a wavelength of 254 nm. From five tested strains identified as Bacillus subtilis, Bacillus pumilus, Enterobacter cloacae, Rhizobium radiobacter and Acinetobacter pitii, isolated from gouda type cheese, the greatest ability of degradation was observed in Bacillus subtilis, which was capable to degrade almost all amount of histamine, cadaverine and putrescine. Other four strains showed a lower rate of degradation than Bacillus subtilis, but the ability to degrade biogenic amines with these microorganisms was still significant.

  12. Assessment of workers' exposure to bioaerosols in a French cheese factory.

    Science.gov (United States)

    Simon, Xavier; Duquenne, Philippe

    2014-07-01

    Hundreds of different cheeses are produced in France, where 23.9kg of cheese were consumed per inhabitant in 2009, when it was ranked the second cheese-consuming nation. To meet this considerable demand, a large number of cheese factories exist where many workers, especially cheese washers, may be exposed to fungal bioaerosols that can lead to adverse toxinic and allergic effects. Airborne bacteria, fragments, or microbial by-products (endotoxins) are also found and contribute to total worker exposure. However, there is almost no published data concerning worker exposure or characteristics of bioaerosols emitted during these activities. Here, we measured the parameters (concentrations, species present, and size distribution) of the culturable fungal bioaerosol emitted in a French natural-rind cheese-maturing cellar. Concentrations of airborne bacteria and endotoxins were also measured. The main tasks were investigated using stationary or personal sampling over three consecutive days. Depending on the work area, high concentrations of culturable mesophilic microorganisms were measured (using closed-face cassettes): from 10(4) to 2×10(8) CFU m(-3) for fungi and from 10(3) to 10(6) CFU m(-3) for bacteria. These concentrations are 10- to 100000-fold higher than those measured at two reference points (indoor and outdoor) that are assumed not to be contaminated by the plant's activities. Endotoxin concentrations were between 10 and 300 EU m(-3) in the plant. Exposure was further assessed by identifying the predominant culturable fungi (allergenic Mucor fuscus and Penicillium sp.) and by measuring particle size distributions (cascade impactor). Airborne fungal entities (spores, mycelium strands and fragments, agglomerates, etc.) were found with aerodynamic diameters from 3 to over 20 µm. A metrological approach was used to fully characterize the culturable fungal aerosols generated during cheese maturing in this plant. The results show that workers are exposed to

  13. Investigation of the activity of the microorganisms in a Reblochon-style cheese by metatranscriptomic analysis

    Directory of Open Access Journals (Sweden)

    Christophe eMonnet

    2016-04-01

    Full Text Available The microbial communities in cheeses are composed of varying bacteria, yeasts, and molds, which contribute to the development of their typical sensory properties. In situ studies are needed to better understand their growth and activity during cheese ripening. Our objective was to investigate the activity of the microorganisms used for manufacturing a surface-ripened cheese by means of metatranscriptomic analysis. The cheeses were produced using two lactic acid bacteria (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus, one ripening bacterium (Brevibacterium aurantiacum, and two yeasts (Debaryomyces hansenii and Geotrichum candidum. RNA was extracted from the cheese rinds and, after depletion of most ribosomal RNA, sequencing was performed using a short-read sequencing technology that generated approximately 75 million reads per sample. Except for Brevibacterium aurantiacum, which failed to grow in the cheeses, a large number of CDS reads were generated for the inoculated species, making it possible to investigate their individual transcriptome over time. From day 5 to day 35, G. candidum accounted for the largest proportion of CDS reads, suggesting that this species was the most active. Only minor changes occurred in the transcriptomes of the lactic acid bacteria. For the two yeasts, we compared the expression of genes involved in the catabolism of lactose, galactose, lactate, amino acids and free fatty acids. During ripening, genes involved in ammonia assimilation and galactose catabolism were down-regulated in the two species. Genes involved in amino acid catabolism were up-regulated in G. candidum from day 14 to day 35, whereas in D. hansenii, they were up-regulated mainly at day 35, suggesting that this species catabolized the cheese amino acids later. In addition, after 35 days of ripening, there was a down-regulation of genes involved in the electron transport chain, suggesting a lower cellular activity. The

  14. Biogas - a contribution to the solution of the problem of energy supply for cheese factories

    Energy Technology Data Exchange (ETDEWEB)

    Favre, R; Bachmann, M

    1985-01-01

    During a two years period the energy consumption of four different cheese factories has been analysed. The whey of the four cheese factories is used for fattening pigs in an attached piggery. All four factories are equipped with biogas-digesters which use the slurry from the piggeries for methane production. The overall energy consumption per ton of milk transformed varies from 600 and 885 MJ. This includes the energy used for heating the fermentation rooms and the cheese maker's flat as well as the energy used for the piggery. 10 to 40% of the total energy is being consumed in form of electricity. Three of the four digesters are working at temperatures of 30 to 35/sup 0/C. One is run in the psychrophilic range, i.e. without heating system. The heated systems use 20 to 40% of the total gas production for heating the digesters. The net gas production of all four systems is of the same order of magnitude. The necessary energy for milk transformation depends on the type of installation used and on the skill of the cheese maker to use his installation economically. Between 30 and 60% of the total energy demand of the four factories has been covered by biogas. Economic problems regarding the use of biogas in cheese factories are discussed.

  15. Tracing and inhibiting growth of Staphylococcus aureus in barbecue cheese production after product recall.

    Science.gov (United States)

    Johler, S; Zurfluh, K; Stephan, R

    2016-05-01

    Staphylococcal food poisoning is one of the most prevalent causes of foodborne intoxication worldwide. It is caused by ingestion of enterotoxins formed by Staphylococcus aureus during growth in the food matrix. Following a recall of barbecue cheese due to the detection of staphylococcal enterotoxins in Switzerland in July 2015, we analyzed the production process of the respective dairy. Although most cheese-making processes involve acidification to inhibit the growth of pathogenic bacteria, barbecue cheese has to maintain a pH >6.0 to prevent undesired melting of the cheese. In addition, the dairy decided to retain the traditional manual production process of the barbecue cheese. In this study, therefore, we aimed to (1) trace Staph. aureus along the barbecue cheese production process, and (2) develop a sustainable strategy to inhibit growth of Staph. aureus and decrease the risk of staphylococcal food poisoning without changing the traditional production process. To this end, we traced Staph. aureus in a step-wise blinded process analysis on 4 different production days using spa (Staphylococcus protein A gene) typing, DNA microarray profiling, and pulsed-field gel electrophoresis analysis. We subsequently selected a new starter culture and used a model cheese production including a challenge test assay to assess its antagonistic effect on Staph. aureus growth, as well as its sensory and technological implications. We detected Staph. aureus in 30% (37/124) of the collected samples taken from the barbecue cheese production at the dairy. This included detection of Staph. aureus in the final product on all 4 production days, either after enrichment or using quantitative detection. We traced 2 enterotoxigenic Staph. aureus strains (t073/CC45 and t282/CC45) colonizing the nasal cavity and the forearms of the cheesemakers to the final product. In the challenge test assay, we were able to show that the new starter culture inhibited growth of Staph. aureus while meeting

  16. Feasibility of extending storage life of sheep-milk cheese using ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Krcal, Z; Prekoppova, J; Slottova, A [Vyskumny Ustav Mliekarensky, Zilina (Czechoslovakia)

    1978-12-01

    3 types of winter full-fat sheep cheese were /sup 60/Co gamma irradiated with doses of 75, 100, 200, and 500 krads, this 48 hours after production. Within a week-long storage the organoleptic properties of the cheeses were repeatedly evaluated. The irradiation was found to significantly reduce all microorganism groups. Doses above 100 krads were found to be unsuitable; cheese taste deteriorated and was defined as ''scorched, strange, impure''. Although during storage these defects disappear, the individual main components of proteins and lipids decompose due to enzyme activity, which results in a rapid deterioration of the product. The dose of 75 krads did not cause any taste defects and storage life was extended by four days as against the stated guarantee period.

  17. Concerns about the microbiological quality of traditional raw milk cheeses: a worldwide issue

    Directory of Open Access Journals (Sweden)

    Erica Tirloni

    2014-11-01

    Full Text Available Six types of unripened raw milk fresh (Robiola, Crescenza, Primo sale and Formaggella and  “pasta filata” cheeses (Mozzarella and Burrata were evaluated for microbiological parameters. No Listeria monocytogenes or Salmonella spp. were detected, but high microbial counts were revealed. Significantly higher Total Viable Counts (TVC and Enterobacteriaceae counts were observed in “fresh cheese” than in “pasta filata” samples. Values > 6 Log CFU/g were found in 81.3% of fresh vs 50% in pasta filata for TVC and 65.6% vs 12.5% for Enterobacteriaceae, respectively. An evident contamination by Escherichia coli, Coagulase-positive Staphylococci and Pseudomonas spp. was detected in all the cheeses: the causes could be the improper hygiene of the artisanal production practices and the permanence of the cheeses on the refrigerated shelves. A careful attention to the respect of the good manufacturing practices is suggested to avoid the presence of initial high bacterial loads.

  18. Feasibility of extending storage life of sheep-milk cheese using ionizing radiation

    International Nuclear Information System (INIS)

    Krcal, Z.; Prekoppova, J.; Slottova, A.

    1978-01-01

    3 types of winter full-fat sheep cheese were 60 Co gamma irradiated with doses of 75, 100, 200, and 500 krads, this 48 hours after production. Within a week-long storage the organoleptic properties of the cheeses were repeatedly evaluated. The irradiation was found to significantly reduce all microorganism groups. Doses above 100 krads were found to be unsuitable; cheese taste deteriorated and was defined as ''scorched, strange, impure''. Although during storage these defects disappear, the individual main components of proteins and lipids decompose due to enzyme activity, which results in a rapid deterioration of the product. The dose of 75 krads did not cause any taste defects and storage life was extended by four days as against the stated guarantee period. (B.S.)

  19. Pseudomonas sp. BUP6, a novel isolate from Malabari goat produces an efficient rhamnolipid type biosurfactant.

    Science.gov (United States)

    Priji, Prakasan; Sajith, Sreedharan; Unni, Kizhakkepowathial Nair; Anderson, Robin C; Benjamin, Sailas

    2017-01-01

    This study describes the characteristics of a biosurfactant produced by Pseudomonas sp. BUP6, a rumen bacterium, and optimization of parameters required for its production. Initial screening of five parameters (pH, temperature, agitation, incubation, and substrate concentration) was carried out employing Plackett-Burman design, which reduced the number of parameters to 3 (pH, temperature, and incubation) according to their significance on the yield of biosurfactant. A suitable statistical model for the production of biosurfactant by Pseudomonas sp. BUP6 was established according to Box-Behnken design, which resulted in 11% increase (at pH 7, 35 °C, incubation 75 h) in the yield (2070 mg L -1 ) of biosurfactant. The biosurfactant was found stable at a wide range of pH (3-9) with 48 mg L -1 critical micelle concentration; and maintained over 90% of its emulsification ability even after boiling and in presence of sodium chloride (0.5%). The highest cell hydrophobicity (37%) and emulsification (69%) indices were determined with groundnut oil and kerosene, respectively. The biosurfactant was found to inhibit the growth and adhesion of E. coli and S. aureus significantly. From the phytotoxicity studies, the biosurfactant did not show any adverse effect on the germinating seeds of rice and green gram. The structural characterization of biosurfactant employing orcinol method, thin layer chromatography and FT-IR indicated that it is a rhamnolipid (glycolipid). Thus, Pseudomonas sp. BUP6, a novel isolate from Malabari goat is demonstrated as a producer of an efficient rhamnolipid type biosurfactant suitable for application in various industries. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. 21 CFR 133.186 - Sap sago cheese.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Sap sago cheese. 133.186 Section 133.186 Food and... Products § 133.186 Sap sago cheese. (a) Description. (1) Sap sago cheese is the food prepared by the... method described in § 133.5. Sap sago cheese is not less than 5 months old. (2) One or more of the dairy...

  1. Hepatic Flavin-Containing Monooxygenase 3 Enzyme Suppressed by Type 1 Allergy-Produced Nitric Oxide.

    Science.gov (United States)

    Tanino, Tadatoshi; Bando, Toru; Komada, Akira; Nojiri, Yukie; Okada, Yuna; Ueda, Yukari; Sakurai, Eiichi

    2017-11-01

    Flavin-containing monooxygenases (FMOs) are major mammalian non-cytochrome P450 oxidative enzymes. T helper 2 cell-activated allergic diseases produce excess levels of nitric oxide (NO) that modify the functions of proteins. However, it remains unclear whether allergy-induced NO affects the pharmacokinetics of drugs metabolized by FMOs. This study investigated alterations of hepatic microsomal FMO1 and FMO3 activities in type 1 allergic mice and further examined the interaction of FMO1 and FMO3 with allergy-induced NO. Imipramine (IMP; FMO1 substrate) N- oxidation activity was not altered in allergic mice with high serum NO and immunoglobulin E levels. At 7 days after primary sensitization (PS7) or secondary sensitization (SS7), benzydamine (BDZ; FMO1 and FMO3 substrate) N- oxygenation was significantly decreased to 70% of individual controls. The expression levels of FMO1 and FMO3 proteins were not significantly changed in the sensitized mice. Hepatic inducible NO synthase (iNOS) mRNA level increased 5-fold and 15-fold in PS7 and SS7 mice, respectively, and hepatic tumor necrosis factor- α levels were greatly enhanced. When a selective iNOS inhibitor was injected into allergic mice, serum NO levels and BDZ N- oxygenation activity returned to control levels. NO directly suppressed BDZ N- oxygenation, which was probably related to FMO3-dependent metabolism in comparison with IMP N- oxidation. In hepatic microsomes from PS7 and SS7 mice, the suppression of BDZ N- oxygenation was restored by ascorbate. Therefore, type 1 allergic mice had differentially suppressed FMO3-dependent BDZ N- oxygenation. The suppression of FMO3 metabolism related to reversible S- nitrosyl modifications of iNOS-derived NO. NO is expected to alter FMO3-metabolic capacity-limited drug pharmacokinetics in humans. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  2. Investigation on the Protein Degradation, Free Fatty Acid Content and Area Fraction of Poosti Cheese, Iranian Traditional Cheese Ripened in Skin

    Directory of Open Access Journals (Sweden)

    Mojgan Hemmatian

    2015-03-01

    Full Text Available Background and Objectives: In this study, the proteolysis and lipolysis of Poosti cheese produced from raw sheep milk in mountainous eastern regions of Iran were investigated during 90 days of ripening. Materials and Methods: Sodium dodecyl sulfate polyacrylamide gel electrophoresis for proteolysis (SDS-PAGE and gas chromatography (GC for free fatty acids (FFAs were applied to investigate the intensity of lipid degradation. To evaluate the Poosti cheese microstructural changes, the area fraction parameter of the scanning electron microscopy (SEM micrographs was also calculated by the Image J software. Results: The most alteration in protein profile was occurred in the first month of aging for high activity of the proteolytic microorganisms in this period. The amount of free fatty acids was depended on their length due to the variety of involved mechanisms. In addition, the microstructural parameter was considerably affected by the aging as a consequence of the effect of salt on the activity of raw milk and skin micro flora. Conclusions: The decline in proteolysis rate during the last stage of aging could be correlated with the inhibitory effects of salt on the engaged microorganisms, and increase in the pore fraction of the microstructure during the first month of Poosti cheese aging could be due to casein rearrangement and gas release by the fermentative activity of microorganisms. Keywords: Proteolysis, Lipolysis, Poosti cheese, Raw sheep milk.

  3. Comparison of friction produced by two types of orthodontic bracket protectors.

    Science.gov (United States)

    de Lima Mendonça, Steyner; Praxedes Neto, Otávio José; de Oliveira, Patricia Teixeira; dos Santos, Patricia Bittencourt Dutra; de Sá Leitão Pinheiro, Fábio Henrique

    2014-01-01

    Fixed orthodontic appliances have been regarded as a common causative factor of oral lesions. To manage soft tissue discomfort, most orthodontists recommend using a small amount of utility wax over the brackets in order to alleviate trauma. This in vitro study aimed at evaluating friction generated by two types of bracket protectors (customized acetate protector [CAP] and temporary resin protector [TRP]) during the initial stages of orthodontic treatment. An experimental model (test unit) was used to assess friction. In order to measure the friction produced in each test, the model was attached to a mechanical testing machine which simulated maxillary canines alignment. Intergroup comparison was carried out by one-way ANOVA with level of significance set at 5%. The friction presented by the TRP group was statistically higher than that of the control group at 6 mm. It was also higher than in the control and CAP groups in terms of maximum friction. The customized acetate protector (CAP) demonstrated not to interfere in friction between the wire and the orthodontic bracket slot.

  4. Search for singly produced vector-like down-type quarks with ATLAS

    Energy Technology Data Exchange (ETDEWEB)

    Rehnisch, Laura; Dietrich, Janet; Lacker, Heiko [Humboldt-Universitaet zu Berlin (Germany)

    2016-07-01

    Vector-like quarks are predicted in several models, e.g. composite Higgs models. Due to relatively high mass limits from previous searches and the limited phase space for pair-produced heavy quarks, it is indicated to investigate single production of these particles. A search for down-type vector-like quarks decaying to a W boson and a top quark, conducted on the 8 TeV dataset recorded in 2012 with the ATLAS detector, is presented. Two models, a vector-like quark, B, and an excited quark with vector-like couplings, b{sup *}, have been investigated. The presented and recently published results were obtained using single-lepton and dilepton final states, while the presentation focuses on single-lepton events in which boosted decay topologies of the heavy quarks are used. This increases the sensitivity, as jets from hadronically decaying W's and tops are likely to be merged. In the absence of a significant excess of the data over the expected background, cross-section limits were set. Excited vector-like quarks with masses below 1.5 TeV are excluded.

  5. Cheesemaking in highland pastures: Milk technological properties, cream, cheese and ricotta yields, milk nutrients recovery, and products composition.

    Science.gov (United States)

    Bergamaschi, M; Cipolat-Gotet, C; Stocco, G; Valorz, C; Bazzoli, I; Sturaro, E; Ramanzin, M; Bittante, G

    2016-12-01

    Summer transhumance of dairy cows to high Alpine pastures is still practiced in many mountainous areas. It is important for many permanent dairy farms because the use of highland pastures increases milk production and high-priced typical local dairy products often boost farm income. As traditional cheese- and ricotta-making procedures in Alpine pastures are central to this dairy system, the objective of this study was to characterize the quality and efficiency of products and their relationships with the quality and availability of grass during the grazing season. The milk from 148 cows from 12 permanent farms reared on a temporary farm located in Alpine pastures was processed every 2wk during the summer (7 cheesemakings from late June to early September). During each processing, 11 dairy products (4 types of milk, 2 by-products, 3 fresh products, and 2 ripened cheeses) were sampled and analyzed. In addition, 8 samples of fresh forage from the pasture used by the cows were collected and analyzed. At the beginning of the pasture season the cows were at 233±90d in milk, 2.4±1.7 parities, and produced 23.6±5.7kg/d of milk. The milk yield decreased with the move from permanent to temporary farms and during the entire summer transhumance, but partly recovered after the cows returned to the permanent farms. Similar trends were observed for the daily yields of fat, protein, casein, lactose, and energy, as we found no large variations in the quality of the milk, with the exception of the first period of Alpine pasture. The somatic cell counts of milk increased during transhumance, but this resulted from a concentration of cells in a lower quantity of milk rather than an increase in the total number of cells ejected daily from the udder. We noted a quadratic trend in availability of forage (fresh and dry matter weight per hectare), with a maximum in late July. The quality of forage also varied during the summer with a worsening of chemical composition. The evening milk

  6. Cheese from ultrafiltered milk : whey proteins and chymosin activity

    NARCIS (Netherlands)

    Buijsse, C.A.P.

    1999-01-01

    The manufacture of (semi-)hard cheese from ultrafiltered milk (UF-cheese) enables the partial incorporation of whey proteins in the cheese, thereby increasing its yield. The transfer of whey proteins in curd from (UF-)milk was studied in relation to the degree of ultrafiltration of the milk

  7. 21 CFR 133.173 - Pasteurized process cheese food.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Pasteurized process cheese food. 133.173 Section 133.173 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific...

  8. 21 CFR 133.147 - Grated American cheese food.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Grated American cheese food. 133.147 Section 133.147 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION CHEESES AND RELATED CHEESE PRODUCTS Requirements for Specific Standardized...

  9. Factors affecting proteolytic action of Lactococcus lactis in cheese

    NARCIS (Netherlands)

    Youssef, Y.B.

    1992-01-01

    Model cheeses were developed to study the behaviour of proteolytic agents involved in cheese maturation under conditions that closely resemble those in normal cheese. The models were applied to study protein breakdown by Lactococcus lactis ssp. cremoris HP , as a

  10. Viscoelasticity of Edam cheese during its ripening

    Directory of Open Access Journals (Sweden)

    Šárka Nedomová

    2010-01-01

    Full Text Available Series of the indentation of the ball (10 mm in diameter by the constant speed into blocks of Edam cheese has been conducted. The indentation tests were performed at different speeds (1, 5, 10, 20 and 100 mm/min, and the corresponding force–displacement responses were fitted with an analytical solution to obtain the time-dependent constants and the instantaneous force–displacement response. The measurement has been performed for the cheeses of different stages of their maturity. The dependence of the indentation force on the penetration depth has been evaluated. This dependence can be fitted by a polynom. The indentation force decreases with cheese fat content. It increases with the loading rate. Its value also decreases with the time of the cheese ripening. The recently proposed method for the indenation of the ball into viscoelastic solids has been used for our data analysis. This procedure, which needs the use of the numeric methods, enables to obtain stress relaxation moduli, which describe the viscoelasticity of the tested materials. The obtained moduli describe the stage of the cheese maturity.

  11. Quality of Milk for Cheese Production on Registered Agricultural Holdings in Vojvodina

    Directory of Open Access Journals (Sweden)

    Popović Vranješ Anka

    2017-12-01

    Full Text Available Currently, milk producers in Vojvodina on registered agricultural holdings (RAHs have great experience and knowledge in managing their farms, including primary production, processing and sales. However, for a smaller number of manufacturers, there is still room for organizational and technological improvement of production. Nowadays, goat breeding is a very important part of sustainable production, rural development, and represents a very important part of rural development and employment of people. The course of goat breeding in our country is milk-meat, where milk is usually a priority. For the successful production of cheese, the quality of raw milk plays a critical role. It affects the quality of cheese in terms of a chemical composition, microbiological quality, the presence of chemical residues and organoleptic properties. Cheese is mostly made from cow, goat and sheep milk. The valuable components of milk are proteins and fats. These can also be defined as parameters of utilization, since they indicate how much cheese can be obtained from milk. On average, cow milk contains 3.64% fat, 3.22% protein, and 8.52% non-fat dry matter (NFDM. Higher differences in milk fat content (minimum 3.25%, maximum 4.36% were found in milk from RAHs. Recently, the production of milk with higher fat content has become important, since in Serbian milk there is not enough milk fat, so some processors are obliged to import it in the form of butter and cream. In addition to the chemical composition, the microbiological quality of milk is important to maintain successful cheese production. Regarding our findings, the standard plate count (SPC and the somatic cell count (SCC in samples from most RAHs did not exceed the values specified in Regulation (EC 853/2004. Moreover, goat and sheep milk was in agreement with the technological quality of milk for cheese production, in terms of chemical composition.

  12. Quality of milk used in informal artisanal production of coalho and butter cheeses

    Directory of Open Access Journals (Sweden)

    Natália Cristina de Medeiros

    2017-08-01

    Full Text Available Artisanal cheeses such as coalho and butter participate in the socio-cultural identity of people and deserve recognition. Like many artisanal cheeses, it is common to produce coalho and butter cheeses from raw milk. For this reason, it is essential that the raw material from dairies is of good quality to minimize risks to consumers. Thus, this study aimed to evaluate the quality of milk in artisanal cheese factories in Rio Grande do Norte, Brazil. Fifty samples were collected from areas that stand out in dairy production in the state. These samples underwent microbiological and physical–chemical analysis, as well as antibiotic residue and fraud searches. Viable strict and facultative mesophilic bacteria were surveyed, in addition to total and thermotolerant coliforms, Salmonella sp., and Staphylococcus aureus; titratable acidity in Dornic degrees, density, cryoscopy, stability to alizarol, and percentages of protein, lactose, and fat contents were also measured, and tests for residues and recurrent fraud in milk were conducted. In general, all samples exceeded the limit established by law for mesophilic bacteria counting; Salmonella sp. was found in one sample. Given this contamination, the acidity of 76% of the samples was higher than allowed by the legislation. Regarding fat and protein parameters, 14% and 10% of the samples were below the required values by the legislation, respectively. Furthermore, there is suspicion of fraud by adding water in 24% of samples. Chlorides were found in 16% and antimicrobial residues in 46% of samples. Therefore, the quality of the milk used in informal artisanal cheese making in the state of Rio Grande do Norte is poor and may pose a risk to consumers, with the loss of quality of coalho and butter cheeses.

  13. Habit Formation in Natural Cheese Consumption An Approach Based on Dynamic Demand Analysis

    OpenAIRE

    WAKABAYASHI, Katsufumi

    2010-01-01

    In expectation of growing cheese consumption, natural cheese production is being increased to reduce surplus milk and create high added value in raw milk. Other studies found positive trends in cheese consumption. However, those studies neither clarified recent trends, nor distinguished natural cheese from processed cheese. The purpose of this paper is to discuss the structure of natural cheese consumption, focusing on habit formation. We test structural changes in cheese demand using dynamic...

  14. Dissemination of NDM-1-Producing Enterobacteriaceae Mediated by the IncX3-Type Plasmid

    Science.gov (United States)

    Fu, Ying; Du, Xiaoxing; Shen, Yuqin; Yu, Yunsong

    2015-01-01

    The emergence and spread of NDM-1-producing Enterobacteriaceae have resulted in a worldwide public health risk that has affected some provinces of China. China is an exceptionally large country, and there is a crucial need to investigate the epidemic of bla NDM-1-positive Enterobacteriaceae in our province. A total of 186 carbapenem-resistant Enterobacteriaceae isolates (CRE) were collected in a grade-3 hospital in Zhejiang province. Carbapenem-resistant genes, including bla KPC, bla IMP, bla VIM, bla OXA-48 and bla NDM-1 were screened and sequenced. Ninety isolates were identified as harboring the bla KPC-2 genes, and five bla NDM-1-positive isolates were uncovered. XbaI-PFGE revealed that three bla NDM-1-positive K. pneumoniae isolates belonged to two different clones. S1-PFGE and southern blot suggested that the bla NDM-1 genes were located on IncX3-type plasmids with two different sizes ranging from 33.3 to 54.7 kb (n=4) and 104.5 to 138.9 kb (n=1), respectively, all of which could easily transfer to Escherichia coli by conjugation and electrotransformation. The high-throughput sequencing of two plasmids was performed leading to the identification of a smaller 54-kb plasmid, which had high sequence similarity with a previously reported pCFNDM-CN, and a larger plasmid in which only a 7.8-kb sequence of a common gene environment around bla NDM-1 (bla NDM-1-trpF- dsbC-cutA1-groEL-ΔInsE,) was detected. PCR mapping and sequencing demonstrated that four smaller bla NDM-1 plasmids contained a common gene environment around bla NDM-1 (IS5-bla NDM-1-trpF- dsbC-cutA1-groEL). We monitored the CRE epidemic in our hospital and determined that KPC-2 carbapenemase was a major risk to patient health and the IncX3-type plasmid played a vital role in the spread of the bla NDM-1 gene among the CRE. PMID:26047502

  15. The language of cheese-ripening cultures

    DEFF Research Database (Denmark)

    Gori, Klaus; Jespersen, Lene

    2010-01-01

    Microbial interactions are of importance for the establishment and growth of cheese ripening cultures. An interesting aspect of microbial interactions is cell-cell communication, often referred to as quorum sensing; the process in which micro-organisms communicate with signalling molecules and co......-ordinate gene expression in a cell density dependent manner. Little is known about quorum sensing in foods. However, as quorum sensing is expected to be a general phenomenon in micro-organisms, it is likely to be of importance for micro-organisms in foods. An example of a food product where quorum sensing could...... be of importance is surface ripened cheeses. The present review focuses on our findings on quorum sensing systems in cheese ripening cultures. The main focus is on the group of bacterial non-species-specific signalling molecules referred to as autoinducer-2 (AI-2) in smear bacteria as well as alcohol...

  16. Identification and characterization of wild lactobacilli and pediococci from spontaneously fermented Mountain cheese.

    Science.gov (United States)

    Carafa, Ilaria; Nardin, Tiziana; Larcher, Roberto; Viola, Roberto; Tuohy, Kieran; Franciosi, Elena

    2015-06-01

    The Traditional Mountain Malga (TMM) cheese is made from raw cow's milk by spontaneously fermentation in small farms called "Malga" located in Trentino region. This study was designed to characterize the lactic acid bacteria (LAB) growing on MRS medium, of TMM-cheese at the end of the ripening. Ninety-five LAB were isolated and genotypically characterized by Randomly Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR) with two primers, species-specific PCR and partial sequencing of 16S rRNA gene. The 95 LAB clustered in 70 biotypes. Pediococcus pentosaceus and Lactobacillus paracasei were the dominant species. Isolates were tested for their growth properties, carbohydrate metabolism, acidifying ability, proteolytic and lipolytic activities, acetoin production, amino-peptidase (AP) activity, biogenic amines production, bile salts hydrolysis, conjugated linoleic acid and γ-aminobutyric acid production. Lb. paracasei isolates resulted to be well adapted to Malga environment and to show the best AP activity and acetoin production. TMM-cheese related LAB showed also interesting health promoting properties and produced bioactive substances. In particular, one Lb. brevis biotype produced a GABA mean value of 129 mg/L that is considered a high concentration. The results confirmed that TMM-cheese resident LAB could be exploited for dairy production. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Acceptability of genetically modified cheese presented as real product alternative

    DEFF Research Database (Denmark)

    Lähteenmäki, Liisa; Grunert, Klaus G.; Ueland, Øydis

    2002-01-01

    alternatives. Consumers in Denmark, Finland, Norway and Sweden (n=738) assessed two cheeses: one was labelled as genetically modified (preferred in an earlier product test) and the other as conventional (neutral in an ealier product test). A smaller control group received two cheeses with blind codes....... Labelling decreased consumers' intentions to buy the originally preferred gm-labelled cheese, but still the intentions were at the same level with the conventionally labelled buy gm cheese could best be explained by respondents' attitudes towards gene technology and perceived taste benefits. General health...... interest was also a reinforcer of intentions for gm cheese with reduced fat content....

  18. Fungal growth and the presence of sterigmatocystin in hard cheese.

    Science.gov (United States)

    Northolt, M D; van Egmond, H P; Soentoro, P; Deijll, E

    1980-01-01

    Molds isolated from visibly molded cheeses in shops, households, and warehouses have been identified. Mold flora of cheeses in shops and households consisted mainly of Penicillium verrucosum var. cyclopium. On cheeses ripening in warehouses, Penicillium verrucosum var. cyclopium, Aspergillus versicolor, Aspergillus repens, and Enicillium verrucosum var. verrucosum were the dominant mold species. Cheese ripening in warehouses and molded with A. versicolor were examined for sterigmatocystin. Nine of 39 cheese samples contained sterigmatocystin in the surface layer in concentrations ranging from 5 to 600 micrograms/kg.

  19. Findings of Escherichia coli and Enterococcus spp. in homemade cheese

    Directory of Open Access Journals (Sweden)

    Tambur Zoran

    2007-01-01

    Full Text Available During the period from February until March 2004, 108 samples of soft cheese originating from markets of Pancevo, Subotica and Belgrade were examined. Microbiological analyses of the cheese samples to the presence of Escherichia coli was performed using methods described in the Regulations on methods for performing microbiological analyses and super analyses of consumer articles, while the presence of bacteria Enteroccocus spp. was performed on the dexter agar. From 108 samples of soft cheese from the territories of Pancevo, Belgrade and Subotica were isolated: Enterococcus spp. from 96% and Escherichia coli from 69%, cheese samples. Verocytotoxic E.coli was not isolated from any of the taken cheese samples.

  20. Presença de Staphylococcus spp. produtores de enterotoxinas e da toxina da síndrome do choque tóxico em manipuladores de queijo de cabra Presence of Staphylococcus strains producer of enterotoxins and toxic shock toxin syndrome isolated from goat's cheese handlers

    Directory of Open Access Journals (Sweden)

    L.S. Rapini

    2005-12-01

    Full Text Available Agruparam-se 167 cepas de Staphylococcus, isoladas de diferentes sítios (fossas nasais, orofaringe, palma das mãos e leitos subungueais, de dois manipuladores de queijos de leite de cabra, em pools (45, de acordo com a similaridade da espécie e o local de origem, e testou-se o seu potencial de produção de enterotoxinas (SE A, B, C e D, e da toxina da síndrome do choque tóxico (TSST-1. Constatou-se que 62,2% dos pools foram capazes de produzir, de forma individual ou associada, SEA (33,3%; SEB (46,7%; SEC (8,9%; SED (4,4% e TSST-1 (4,4%. Dos pools enterotoxigênicos, 96,4% corresponderam a espécies coagulase negativa (Staphylococcus epidermidis e Staphylococcus cohnii. A capacidade de produção de SE e de TSST-1 pelas cepas de Staphylococcus spp. isoladas dos manipuladores, além de reafirmar sua importância na transmissão de intoxicações de origem alimentar, enfatiza a necessidade imprescindível da adoção de condutas higiênicas e sanitárias durante a manipulação do alimento.A total of 167 strains of Staphylococcus isolated from nasal cavities, oropharynx, palm of hands and subunguial of two goat's cheese handlers were collected. The strains were pooled (45 according to the species similarity and place of origin and tested for the production of enterotoxins (SE A, B, C, D and toxic shock toxin syndrome (TSST-1. It was observed that 62.2% of the pools presented the capacity to produce, individually or in association, SEA (33.3%; SEB (46.7%; SEC (8.9%; SED (4.4% and TSST-1 (4.4%. From the enterotoxigenic pools, 96.4% corresponded to species negative coagulase (Staphylococcus epidermidis and Staphylococcus cohnii. The capacity to produce SE and TSST-1 by Staphylococcus spp. strains isolated from food handlers reaffirms its hole on the transmission of food poisoning, beyond emphasizing the indispensable necessity of the adoption of satisfactory hygienic and sanitary procedures during the food manufacture.

  1. Influence of vegetable coagulant and ripening time on the lipolytic and sensory profile of cheeses made with raw goat milk from Canary breeds.

    Science.gov (United States)

    Rincón, Arturo A; Pino, Verónica; Fresno, María R; Jiménez-Abizanda, Ana I; Álvarez, Sergio; Ayala, Juan H; Afonso, Ana M

    2017-04-01

    Free fatty acids and sensory profiles were obtained for cheeses made with raw goat milk and vegetable coagulant, derived from the cardoon flower ( Cynara cardunculus), at different ripening times (7 and 20 days). A solid-liquid phase extraction method followed by solid-phase extraction and gas chromatography was used. Profiles were also obtained with cheeses made with commercial coagulant, traditional kid rennet paste, and mixture coagulant (vegetable coagulant-kid rennet). The use of vegetable coagulant and vegetable coagulant-kid rennet is common in traditional Protected Designation of Origin cheeses such as " Queso Flor de Guía" and " Queso Media Flor de Guía" (Spain). Contents of short-chain free fatty acids (7.5-22.5 mmol·kg -1 ), medium-chain free fatty acids (0.4-3.7 mmol·kg -1 ), and long-chain free fatty acids (0.2-2.1 mmol·kg -1 ) varied depending on the coagulant type and the ripening time. Vegetable coagulant cheeses present odour intensity and flavour intensity much higher than commercial coagulant cheeses in the sensory analysis for cheeses obtained with seven days of ripening, but the values decrease when increasing the ripening time. Multivariate analysis allowed us to differentiate cheese samples according to the ripening time when using lipolytic profile and according to the coagulant type using the sensory profile.

  2. Probiotic Properties of Lactic Acid Bacteria Isolated from Croatian Fresh Soft Cheese and Serbian White Pickled Cheese

    Directory of Open Access Journals (Sweden)

    Ksenija Uroić

    2014-01-01

    Full Text Available The aim of this study is to gain insight into the probiotic potential of autochthonous lactic acid bacteria (LAB isolated from artisanal fresh soft and white pickled cheeses. Eleven out of 86 LAB isolates from traditionally produced artisanal fresh soft and white pickled cheeses which survived the most rigorous simulated gastrointestinal tract conditions and did not show resistance to antibiotics were subjected to further evaluation for functional probiotic properties. The ability of the examined strains to assimilate cholesterol in the presence of bile salts was strain dependent, with the highest percentage of cholesterol assimilated by strain Lactobacillus brevis BGGO7-28 possessing S-layer proteins on its cell surface. The growth of strains with mannitol or lactulose as the only carbon source was better than with fructooligosaccharides (FOS and inulin as prebiotic substrates, which should be considered in the production of synbiotics. Moreover, the results demonstrated that the strains were highly adhesive to human enterocyte-like Caco-2 cells and to a lesser extent to HT29-MTX cells, with the exception of strain Lb. brevis BGGO7-28, which showed similar percentage of adhesion to both cell lines. This strain was the only one with the acidic cell surface, while other examined strains have the cell surfaces with electron donor and basic properties. In addition, all selected strains decreased the proliferation of gut-associated lymphoid tissue (GALT cells, suggesting possible immunomodulatory potential of the isolates. Finally, the number of viable cells in dry active preparations after lyophilisation depended on the lyoprotectant used (inulin, FOS or skimmed milk, as well as on the strain subjected to lyophilisation. In conclusion, the results obtained in this study demonstrate that particular dairy LAB isolates exhibit strain-specific probiotic properties. Thus, they could be further examined as part of mixed autochthonous starter cultures for

  3. Impact of thistle rennet from Carlina acanthifolia All. subsp. acanthifolia on bacterial diversity and dynamics of a specialty Italian raw ewes' milk cheese.

    Science.gov (United States)

    Cardinali, Federica; Osimani, Andrea; Taccari, Manuela; Milanović, Vesna; Garofalo, Cristiana; Clementi, Francesca; Polverigiani, Serena; Zitti, Silvia; Raffaelli, Nadia; Mozzon, Massimo; Foligni, Roberta; Franciosi, Elena; Tuohy, Kieran; Aquilanti, Lucia

    2017-08-16

    Caciofiore della Sibilla is an Italian specialty soft cheese manufactured with Sopravissana raw ewes' milk and thistle rennet prepared with young fresh leaves and stems of Carlina acanthifolia All. subsp. acanthifolia, according to an ancient tradition deeply rooted in the territory of origin (mountainous hinterland of the Marche region, Central Italy). In this study, the impact of thistle rennet on the bacterial dynamics and diversity of Caciofiore della Sibilla cheese was investigated by applying a polyphasic approach based on culture and DNA-based techniques (Illumina sequencing and PCR-DGGE). A control cheese manufactured with the same batch of ewes' raw milk and commercial animal rennet was analyzed in parallel. Overall, a large number of bacterial taxa were identified, including spoilage, environmental and pro-technological bacteria, primarily ascribed to Lactobacillales. Thistle rennet was observed clearly to affect the early bacterial dynamics of Caciofiore della Sibilla cheese with Lactobacillus alimentarius/paralimentarius and Lactobacillus plantarum/paraplantarum/pentosus being detected in the phyllosphere of C. acanthifolia All., thistle rennet and curd obtained with thistle rennet. Other bacterial taxa, hypothetically originating from the vegetable coagulant (Enterococcus faecium, Lactobacillus brevis, Lactobacillus delbrueckii, Leuconostoc mesenteroides/pseudomesenteroides), were exclusively found in Caciofiore della Sibilla cheese by PCR-DGGE. At the end of the maturation period, Illumina sequencing demonstrated that both cheeses were dominated by Lactobacillales; however curd and cheese produced with thistle rennet were co-dominated by Lactobacillus and Leuconostoc, whereas Lactoccous prevailed in curd and cheese produced with commercial animal rennet followed by Lactobacillus. Differences in the bacterial composition between the two cheeses at the end of their maturation period were confirmed by PCR-DGGE analysis. Copyright © 2017 Elsevier B

  4. COMPARISON OF EEG CHANGES PRODUCED BY CARBARYL (CARBAMATE), PERMETHRIN (TYPE I PYRETHROID), AND DELTAMETHRIN (TYPE II PYRETHROID)

    Science.gov (United States)

    We have reported that treatment with carbaryl may alter Theta activity in the EEG (Lyke et al., Toxicologist, 108(S-1):441, 2009). In this study, we examined the ability to detect changes in EEG activity produced by pesticides with different modes of action. Long Evans rats were ...

  5. Implementation of HACCP system in production of Paški cheese

    Directory of Open Access Journals (Sweden)

    Šime Gligora

    2007-06-01

    Full Text Available Since August 2006 all participants in Republic of Croatia dealing with the food have an obligation to introduce Hazard Analysis of Critical Control Point (HACCP system. Therefore, all producers of dairy products, as well as registered producers of Paški cheese have to implement HACCP system in their facilities. The aim of this work is to describe implementation and use of HACCP system in «Sirena - mala sirana» which is a small-scale cheese factory situated in a place Kolan on the island of Pag. For this reason, EU and Croatian legislative related to HACCP system is firstly described. After that, procedure of certification is presented, as well as prerequisite programsof the system which are the base for successful implementation of the HACCP system. Furthermore, appliance of HACCP in Paški cheese production through system’s documentation is described. Flow diagram is presented, analysis of hazardous and determination of critical control points is described trough defined production processes. Next, control, monitoring and corrective measures for production processes are described. Finally, HACCP plan and Standard Sanitation Operative Procedures (SSOP are presented. Besides that, traceability system and training plan are shown, as well as all required record lists and other documentation for HACCP system. With implementation of the HACCP system in «Sirena» cheese facility, general hygiene was improved as well as hygiene of equipment and personnel. Risk of product contamination is reduced to a minimum level. With effective management of control measures and records, quality of produced Paški cheese was also improved

  6. Water mobility and thermal properties of smoked soft cheese

    Directory of Open Access Journals (Sweden)

    Hanna Maria Baranowska

    2017-01-01

    Full Text Available The main goal of the present study was to characterize the functional parameters of smoked soft cheese, with the emphasis on the behavior of water and milk fat, as analyzed by DSC, which was used to directly measure the melting/freezing phase transitions in the cheese. This study was complemented by NMR measurements of the organization and distribution of the aqueous phase within the emulsions constituting the cheese. The smoked and unsmoked cheeses were characterized by similar compositions in terms of protein (19.08-19.12 g∙100 g-1, fat (18.86-19.02 g∙100 g-1, and water content (59.86-60.27 g∙100 g-1. The water activity was higher in the unsmoked cheese (aw = 0.9736 than in the smoked cheese (aw = 0.9615. This result was confirmed by DSC (higher ice melting enthalpy and NMR (higher T1 value measurements. The smoking process led to differences in the distribution and binding of water to the lipid-protein matrix of the cheese. There was more non-freezed bound water in the smoked cheese which resulted in a more fragile and loosened structure in the smoked cheese than the unsmoked, which manifested in lower values of stretching and meltability. The meltability of the mozzarella smoked cheese was 1.5 times less than that of the unsmoked cheese (tube test and Schreiber test.

  7. Emulsifying salt increase stability of cheese emulsions during holding

    DEFF Research Database (Denmark)

    Hougaard, Anni Bygvrå; Sijbrandij, Anna G.; Varming, Camilla

    2015-01-01

    In cheese powder production, cheese is mixed and melted with water and emulsifying salt to form an emulsion (cheese feed) which is required to remain stable at 60°C for 1h and during further processing until spray drying. Addition of emulsifying salts ensures this, but recent demands for reduction...... of sodium and phosphate in foods makes production of cheese powder without or with minimal amounts of emulsifying salts desirable. The present work uses a centrifugation method to characterize stability of model cheese feeds. Stability of cheese feed with emulsifying salt increased with holding time at 60°C......, especially when no stirring was applied. No change in stability during holding was observed in cheese feeds without emulsifying salt. This effect is suggested to be due to continued exerted functionality of the emulsifying salt, possibly through reorganizations of the mineral balance....

  8. Survival of foot-and-mouth disease virus in cheese.

    Science.gov (United States)

    Blackwell, J H

    1976-09-01

    Persistence of foot-and-mouth disease virus during the manufacture of Cheddar, Mozzarella, Camembert cheese prepared from milk of cows experimentally infected with the virus was studied. Cheese samples were made on a laboratory scale with commercial lactic acid starter cultures and the microbial protease MARZYME as a coagulant. Milk was heated at different temperatures for different intervals before it was made into cheese. Food-and-mouth disease virus survived the acidic conditions of Cheddar and Camembert cheese processing but not that of Mozzarella. Foot-and-mouth disease virus survived processing but not curing for 30 days in Cheddar cheese preparaed from heated milk. However, the virus survived curing for 60 days but not for 120 days in cheese (pH 5) prepared from unheated milk. Foot-and-mouth disease virus survived in Camembert cheese (pH 5) for 21 days at 2 C but not for 35 days.

  9. Protein substitution to produce a processed cheese with high ...

    African Journals Online (AJOL)

    Multiple studies report the beneficial effects of BCAAs supplementation to improve plasma amino acids imbalance, several neurologic diseases, protein energy malnutrition, and subsequently the survival rate of cirrhotic patients. Methods: In the present study we used a protein substitution technique to synthesize a new ...

  10. Protein substitution to produce a processed cheese with high ...

    African Journals Online (AJOL)

    Hoida A.M. El-Shazly

    for liver enzymes; serum total and differential cholesterol profile, serum albumin, globulin and total protein along with .... Colorimetric method was used to determine AST and ALT ..... Studies on inter-organ ammonia exchange in liver cirrhosis ...

  11. H, C, N and S stable isotopes and mineral profiles to objectively guarantee the authenticity of grated hard cheeses

    International Nuclear Information System (INIS)

    Camin, Federica; Wehrens, Ron; Bertoldi, Daniela; Bontempo, Luana; Ziller, Luca; Perini, Matteo; Nicolini, Giorgio; Nocetti, Marco; Larcher, Roberto

    2012-01-01

    Graphical abstract: Random Forest model based on δ 13 C, δ 2 H, δ 15 N, δ 34 S and the content of Sr, Cu, Mo, Re, Na, U, Bi, Ni, Fe, Mn, Ga, Se, Er, Dy, Pb, Li, usable for the protection of PDO Parmigiano Reggiano cheese from mislabelling. The correct classification rate in cross-validation is 98.6%. Highlights: ► The isotopic and elemental profile of over 260 hard cheese samples are discussed. ► Two validated and immediately applicable statistical models are presented. ► One model is able to predict the origin of seven types of European hard cheeses. ► The other one allows to discriminate the PDO Parmigiano Reggiano cheese from imitators. ► The most significant variables are δ 13 C, δ 2 H, δ 15 N, δ 34 S and the content of 16 elements. - Abstract: In compliance with the European law (EC No. 510/2006), geographical indications and designations of origin for agricultural products and foodstuffs must be protected against mislabelling. This is particularly important for PDO hard cheeses, as Parmigiano Reggiano, that can cost up to the double of the no-PDO competitors. This paper presents two statistical models, based on isotopic and elemental composition, able to trace the origin of cheese also in grated and shredded forms, for which it is not possible to check the logo fire-marked on the rind. One model is able to predict the origin of seven types of European hard cheeses (in a validation step, 236 samples out of 240 are correctly recognised) and the other specifically to discriminate the PDO Parmigiano Reggiano cheese from 9 European and 2 extra-European imitators (260 out of 264 correct classifications). Both models are based on Random Forests. The most significant variables for cheese traceability common in both models are δ 13 C, δ 2 H, δ 15 N, δ 34 S and Sr, Cu, Mo, Re, Na, U, Bi, Ni, Fe, Mn, Ga, Se, and Li. These variables are linked not only to geography, but also to cow diet and cheese making processes.

  12. Action of the ionization treatment on the soft cheeses made from unpasteurized milk. Action des rayonnements ionisants sur les fromages a pate molle fabriques au lait cru

    Energy Technology Data Exchange (ETDEWEB)

    Chincholle, R.

    1991-01-01

    The works made on cheeses manufactured with unpasteurized milk, camembert type, have shown that it is possible to use irradiation for their sanitation. The treatment by ionization from 2 to 3 kGy of a cheese made from unpasteurized milk permits the reduction from 10{sup 3} to 10{sup 5} of the bacteria: faecal coliforms, staphylococcus and other indesirable bacteria. The works made by the scientists, J.F. Diell, C. Hauchmann, D. Rilcast, proved that ionization of food has no bad consequences in the nutritional field. Regarding the cheeses made with raw milk this technic brings to the consumer a higher bacteriological security.

  13. Effect of irradiation on the texture of a soft cheese like Camembert

    International Nuclear Information System (INIS)

    Louhichi, Mohamed

    2008-01-01

    The properties texturales and rheological of a cheese of the Camembert cheese type irradiated by gamma radiation with amounts 1, 3, and 5kGy were studied using three mechanical tests with knowing test of penetrometry, test of simple compression and test of compression-relieving using a texturometer of the type TA-XT2i. The parameter textural obtained, for each amount of irradiation, starting from the test of penetrometry is the force with the threshold of rupture (Fsr), whereas starting from the simple test of compression we determined with each amount the maximum compressive force and the Young modulus for a weak deformation (< 0.5 mm). The index of relieving and the time of half-relieving were given starting from the test of compression relieving. One also determined the average maximum compressive force (Fmax moy) to have a deformation of 10%. A statistical study us A makes it possible to conclude that, only that on the level of the test of compression-relieving, the amount of irradiation is regarded as being a significant factor influencing the variation of Fmax moy which can modify the cheese texture. The physico-chemical studies were carried out as well on the crust as on the internal part of cheese do not express any direct relationship to the amount of irradiation used because of the limited number of the repetitions. (Author)

  14. Deproteinization: an integrated-solution approach to increase efficiency in β-galactosidase production using cheese whey powder (CWP solution

    Directory of Open Access Journals (Sweden)

    Leandro Freire dos Santos

    2017-08-01

    Full Text Available Whey is the liquid that results from the coagulation of milk during cheese manufacture. Cheese whey is also an important environmental pollution source. The present experiment sought to compare β-galactosidase (EC 3.2.1.23 production by Aspergillus oryzae from deproteinized and un-deproteinized CWP solutions. β-galactosidase was produced by submerged fermentation in deproteinized or un-deproteinized CWP solutions. To determine the activity of the enzyme, a reaction mixture containing cell-free extract and ortho Nitrophenyl β galactoside (ONPG was used. The results indicated that β-galactosidase induction was greater when using deproteinized CWP solution compared to the un deproteinized CWP solution. These results may enable an alternative management of cheese whey, thereby decreasing its impact on the environment and producing value-added biomacromolecules.

  15. Metagenomic Analysis of Slovak Bryndza Cheese Using Next-Generation 16S rDNA Amplicon Sequencing

    Directory of Open Access Journals (Sweden)

    Planý Matej

    2016-06-01

    Full Text Available Knowledge about diversity and taxonomic structure of the microbial population present in traditional fermented foods plays a key role in starter culture selection, safety improvement and quality enhancement of the end product. Aim of this study was to investigate microbial consortia composition in Slovak bryndza cheese. For this purpose, we used culture-independent approach based on 16S rDNA amplicon sequencing using next generation sequencing platform. Results obtained by the analysis of three commercial (produced on industrial scale in winter season and one traditional (artisanal, most valued, produced in May Slovak bryndza cheese sample were compared. A diverse prokaryotic microflora composed mostly of the genera Lactococcus, Streptococcus, Lactobacillus, and Enterococcus was identified. Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris were the dominant taxons in all tested samples. Second most abundant species, detected in all bryndza cheeses, were Lactococcus fujiensis and Lactococcus taiwanensis, independently by two different approaches, using different reference 16S rRNA genes databases (Greengenes and NCBI respectively. They have been detected in bryndza cheese samples in substantial amount for the first time. The narrowest microbial diversity was observed in a sample made with a starter culture from pasteurised milk. Metagenomic analysis by high-throughput sequencing using 16S rRNA genes seems to be a powerful tool for studying the structure of the microbial population in cheeses.

  16. [Bacteriological evaluation of goat milk and cheese distributed in the Metropolitan Area of San José, Costa Rica].

    Science.gov (United States)

    Araya, Viviana; Gallo, Leslie; Quesada, Carlos; Chaves, Carolina; Arias, María Laura

    2008-06-01

    In the last years, there has been an increase in the production, industrialization and consumption of goat's milk and derivate products, including cheese, worldwide. Nevertheless, in Costa Rica there is no study of these products, reason why the objective of this work was to determine the microbiological characteristics of goat's milk and fresh cheese distributed in the Metropolitan Area of San José, Costa Rica, in order to evaluate its impact in the economical field and as a potential risk for Public Health. A total of 25 raw goat's milk samples, obtained by manual milking from 5 different producers tested in five different dates and 15 cheese samples, elaborated with pasteurized milk, commercially available and coming from three different producers were analyzed. The study included the analysis of spoilage bacteria (total aeobic count and lactic bacteria count), indicators of hygiene (total coliforms), fecal contamination (fecal coliforms), manipulation (Staphylococcus aureus) and pathogens (Listeria monocytogenes and Salmonella spp). High results were obtained for the total aerobic count and lactic bacteria count of the milk and cheese samples, showing a reduced shelf life. Total coliforms, in limits beyond the established ones by the Costa Rican legislation for human consumption raw milk, were found in 100% of milk samples, as well as for fecal coliforms in 76% of them. All cheese samples, except one, were negative for these indicators, suggesting good manufacturing practices. S. aureus counts were low and both Salmonella spp. and L. monocytogenes were not isolated from samples analyzed.

  17. Packaging conditions hindering fungal growth on cheese

    DEFF Research Database (Denmark)

    Nielsen, Per Væggemose; Haasum, Iben

    1997-01-01

    Fungal contamination is one of the most important quality deteriorating factors on cheese. During the last 5 years we have studied in detail the underlying factors controlling these unwanted processes in a collaborative project financed by the Danish Dairy Board and the Ministry of Agriculture...

  18. CMB seen through random Swiss Cheese

    Energy Technology Data Exchange (ETDEWEB)

    Lavinto, Mikko; Räsänen, Syksy, E-mail: mikko.lavinto@helsinki.fi, E-mail: syksy.rasanen@iki.fi [Physics Department, University of Helsinki and Helsinki Institute of Physics, P.O. Box 64, FIN-00014, University of Helsinki (Finland)

    2015-10-01

    We consider a Swiss Cheese model with a random arrangement of Lemaȋtre-Tolman-Bondi holes in ΛCDM cheese. We study two kinds of holes with radius r{sub b}=50 h{sup −1} Mpc, with either an underdense or an overdense centre, called the open and closed case, respectively. We calculate the effect of the holes on the temperature, angular diameter distance and, for the first time in Swiss Cheese models, shear of the CMB . We quantify the systematic shift of the mean and the statistical scatter, and calculate the power spectra. In the open case, the temperature power spectrum is three orders of magnitude below the linear ISW spectrum. It is sensitive to the details of the hole, in the closed case the amplitude is two orders of magnitude smaller. In contrast, the power spectra of the distance and shear are more robust, and agree with perturbation theory and previous Swiss Cheese results. We do not find a statistically significant mean shift in the sky average of the angular diameter distance, and obtain the 95% limit |Δ D{sub A}/ D-bar {sub A}|∼< 10{sup −4}. We consider the argument that areas of spherical surfaces are nearly unaffected by perturbations, which is often invoked in light propagation calculations. The closed case is consistent with this at 1σ, whereas in the open case the probability is only 1.4%.

  19. Lipase in milk, curd and cheese

    NARCIS (Netherlands)

    Geurts, T.J.; Lettink, F.J.; Wouters, J.T.M.

    2003-01-01

    Presence of lipase in milk, curd, whey and cheese was studied. A small amount of the product was added to a large volume of lipase-free whole milk that had been made sensitive to lipolysis by homogenization. Increase of the acidity of the fat in the mixture, determined after incubation, was

  20. Carriage of Escherichia coli Producing CTX-M-Type Extended-Spectrum β-Lactamase in Healthy Vietnamese Individuals.

    Science.gov (United States)

    Bui, Thi Mai Huong; Hirai, Itaru; Ueda, Shuhei; Bui, Thi Kim Ngan; Hamamoto, Kouta; Toyosato, Takehiko; Le, Danh Tuyen; Yamamoto, Yoshimasa

    2015-10-01

    Healthy carriage of CTX-M-type extended-spectrum β-lactamase (ESBL)-producing Escherichia coli was examined by thrice collecting fecal samples from the same 199 healthy Vietnamese subjects every 6 months. Using pulsed-field gel electrophoresis (PFGE), identical PFGE patterns throughout the three samplings were not observed, although prevalence of E. coli in the subjects was around 50% in the three samplings. Our results suggested a short carriage period of the CTX-M-type ESBL-producing E. coli in healthy Vietnamese subjects. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. Short communication: Chemical and sensory characteristics of Canestrato di Moliterno cheese manufactured in spring.

    Science.gov (United States)

    Trani, A; Gambacorta, G; Loizzo, P; Cassone, A; Faccia, M

    2016-08-01

    Canestrato di Moliterno is an Italian Protected Geographical Indication hard cheese, made in winter and spring from a mixture of ewe and goat milks, that has been poorly investigated. The present study was aimed at characterizing the cheese made in the warm season. Two series of samples, ripened in traditional rooms called fondaco as indicated in the official protocol of production, were taken from the main certified producers. The cheeses were analyzed for gross composition; proteolysis and lipolysis; volatile fraction; and organoleptic features. Gross composition was not completely homogeneous among the samples, but primary proteolysis and lipolysis were quite uniform. We observed variations in secondary proteolysis, likely caused by fluctuations in environmental conditions in the fondaco. The sensory profiles of the samples were homogeneous: the cheese was soluble, greasy, and adhesive, with a sheepfold and buttery odor. The main taste attributes were fermented, pungent, and bitter. Overall, the results of this study provide an initial contribution to the characterization of Canestrato di Moliterno, and could be used to improve marketing strategies. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  2. Effect of different concentrations of nisin on starter culture of model Cheeses manufactured from ultrafiltrated milk

    Directory of Open Access Journals (Sweden)

    Kh Mohammadi

    2013-05-01

    Full Text Available Nisin is a natural preservative produced by strains of Lactococcuslactis subsp. Lactis, has been approved for use in food by the Joint Food and Agricultural Organization/World Health Organization (FAO/WHO Committee on Food Additives and has been awarded generally recognized as safe (GRAS. It remains the only bacteriocin allowed in food as an addedpreservative. Nisin has a broad spectrum of antimicrobial activity againstgram-positive bacteria, thus one of the problems associated with nisin application is inhibition of starter culture and prevention of ripening, which is required for development of cheese characteristics during ripening. In the current study, the effects of different concentrations of nisin and temperature on growth and activity of lactic acid bacteria in model cheeses manufactured from ultrafiltrated milk was evaluated. Cheese samples were supplemented with nisin at concentrations of 0, 2, 4 and 6 µg/g and stored at 8 and 25 °C up to 60 days. Microbiological and physico-chemical properties of the cheese samples were analyzedat 0, 1, 8, 15, 30, 45 and 60 days. Results showed that addition of nisin at concentrations of 4 and 6 µg/g affects (p

  3. Effect of adjuncts on sensory properties and consumer liking of Scamorza cheese.

    Science.gov (United States)

    Braghieri, A; Piazzolla, N; Romaniello, A; Paladino, F; Ricciardi, A; Napolitano, F

    2015-03-01

    The present study aimed to evaluate the effect of a peptidolytic adjunct (Lactococcus lactis, Lactobacillus helveticus, and Lactobacillus paracasei), as a tool to accelerate ripening, on sensory properties and acceptability of Scamorza cheese obtained using 2 types of milk (Friesian and Friesian+Jersey) and Streptococcus thermophilus as primary starter. A 10-member panel was trained using a specific frame of references and used a specific vocabulary to assess cheese sensory properties through quantitative descriptive analysis (QDA), whereas 87 consumers were used to evaluate product acceptability. Analysis of variance showed that milk type did not markedly alter cheese sensory properties. Conversely, panelists perceived higher intensities of butter, saltiness, and sweetness flavors in cheese without adjunct culture (ST), whereas the addition of the adjunct culture (ST+A) induced higher and sourness flavors, oiliness and grainy textures, and lower adhesiveness, moisture, springiness, and tenderness. Principal component analysis showed positive relationships between pH and tenderness, sweetness and saltiness and a negative correlation between pH and grainy, oiliness, color and structure uniformity, sourness, and milk. Most of the differences observed in QDA and most of the relationships observed in the principal component analysis were linked to the higher microbial activity induced by the adjunct culture. Independently of milk and starter types, consumers perceived Scamorza cheese as characterized by a good eating quality (mean liking scores were all above the neutral point of the hedonic scale). Although ST cheeses showed higher values for overall liking, 2 homogeneous groups of consumers were identified using partial least squares regression analysis. One group preferred ST cheeses with higher levels of tenderness, adhesiveness, springiness, and moisture in terms of texture, butter in terms of flavor, and sweetness in terms of taste, whereas a second group

  4. Physicochemical and Sensory Properties of Whey Cheese with Pine Nuts

    Directory of Open Access Journals (Sweden)

    Cristina Anamaria Semeniuc

    2015-11-01

    Full Text Available This study aimed to develop a value-added whey cheese through addition of pine nuts. Therefore, different concentrations of pine nuts [2, 4, 6 and 8% (w/w] were added to whey cheese. The study was designed to evaluate the influence of pine nuts on physicochemical and sensory properties of whey cheese. The addition of pine nuts resulted in an increase in fat content and total solids and a decrease in moisture content. However, no statistically significant difference was found in pH values. Sensory analysis was performed using the 9-point hedonic scale, with selected assessors. The whey cheese sample with 4% pine nuts was the most appreciated (7.6 points, followed by the classic whey cheese, whey cheese with 6 and 8% pine nuts (7.4 points, and whey cheese with 2% pine nuts (7.3 points. Nevertheless, the sensory characteristics of whey cheese were not significantly influenced by the addition of pine nuts. Whey cheese sensory profiling was successful in differential characterization of whey cheese samples.

  5. Microbial hazards reduction during creamy cream cheese production

    Directory of Open Access Journals (Sweden)

    Dorota Miarka

    2015-03-01

    Full Text Available The purpose of the work was to identify the hazards relevant to the production of safe food and to assess the effects of a possible infection. The paper presents the microbiological hazards that can occur throughout the production of creamy cream cheese and indicates the means to their minimization or elimination. The analysis of microbiological hazards showed that in the manufacturing process of the type of cheese mentioned, there are a few critical steps that should be specifically overseen. In order to acquire a high quality product it is important to monitor a quality of raw material, the parameters of pasteurization and souring, temperature of product packaging, storage conditions of the finished product and maintain hygiene throughout the production. The process of heat treatment, which is pasteurization, is a critical step (critical control points - CCP for the whole process. Monitoring this stage and consistent adherence to Operational Pre-Condition Programs at the thermisation and centrifuging and later packaging, guarantees a safe product and its long shelf life.

  6. Use of Protease and Lipase Enzymes by Different Methods to Accelerate Kaşar Cheese Ripening 1. The Effect on Cheese Physical and Chemical Properties (Turkish with English Abstract

    Directory of Open Access Journals (Sweden)

    2015-02-01

    Full Text Available In this study, pasteurized cow milk was used for Kaşar cheese processing. One lipase (Palatase M, one protease (Neutrase, and combination of both enzymes were added to milk which was processed into cheese. Three different enzymes with the levels (based on raw milk amount of 0.0001% Palatese M. 0.004% Neutrase and 0.0001% Palatase M + 0.004% Neutrase were evaluated for physical and chemical properties at 2nd, 30th, 60th and 90th day of the ripening periods. Enzyme added cheese samples were compared with the Control-I (from fresh milk and Control-II (from pasteurized and starter added cheese samples. The 1% starter composed of Lactococcus lactis and Streptococcus cremoris (1:1 was added into the milk. Experiment was set up according to random block design with factorial arrangement, and the analysis were carried out in duplicate. Cheese yields of all the cheese samples produced with the enzyme addition were lower than the control groups. But, 0.0001% Palatase M(Mik-L added with microencapsulation technique gave the higher cheese yield which is closer to the control groups. With the enzyme addition, dry-matter; fat, protein, salt, acidity, fat in dry-matter, salt in dry-matter and the ripening degree; with the ripening period dry-matter, fat, protein, ash, salt, acidity, salt in dry-matter and the ripening degree gave statistically (P<0.01 significant results. It was determined that the interaction of enzyme addition x ripened period had an significant influence on dry-matter, fat, protein, acidity, fat in dry-matter and ripening degree of the cheeses produced in this research (P<0.01. The best ripened condition was achieved by adding lipase+protease enzymes together into milk with direct technique (Di-L+P. The same ripened state in the cheeses was reached in 30-60 days ripened period with the direct incorporation of lipase + protease enzymes together (Di+L+P or protease only (Di-P, but in 90 days in control groups containing no enzymes.

  7. Fixed differences in the paralytic gene define two lineages within the Lutzomyia longipalpis complex producing different types of courtship songs.

    Directory of Open Access Journals (Sweden)

    Rachel M M A Lins

    Full Text Available The sand fly Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae, the most important vector of American visceral leishmaniasis, is widely distributed in Latin America. There is currently a consensus that it represents a species complex, however, the number and distribution of the different siblings is still uncertain. Previous analyses have indicated that Brazilian populations of this vector can be divided into two main groups according to the type of courtship song (Burst vs. Pulse males produce during copulation. Nevertheless, no diagnostic differences have been observed between these two groups with most molecular markers used to date. We analyzed the molecular divergence in a fragment of the paralytic (para gene, a locus involved in the control of courtship songs in Drosophila, among a number of Lu. longipalpis populations from Brazil producing Burst and Pulse-type songs. Our results revealed a very high level of divergence and fixed differences between populations producing the two types of songs. We also compared Lu. longipalpis with a very closely related species, Lutzomyia cruzi, which produces Burst-type songs. The results indicated a higher number of fixed differences between Lu. cruzi and the Pulse-type populations of Lu. longipalpis than with those producing Burst-type songs. The data confirmed our previous assumptions that the presence of different sibling species of the Lu. longipalpis complex in Brazil can be divided into two main groups, one representing a single species and a second more heterogeneous group that probably represents a number of incipient species. We hypothesize that para might be one of the genes directly involved in the control of the courtship song differences between these two groups or that it is linked to other loci associated with reproductive isolation of the Brazilian species.

  8. Fixed Differences in the paralytic Gene Define Two Lineages within the Lutzomyia longipalpis Complex Producing Different Types of Courtship Songs

    Science.gov (United States)

    Lins, Rachel M. M. A.; Souza, Nataly A.; Brazil, Reginaldo P.; Maingon, Rhayza D. C.; Peixoto, Alexandre A.

    2012-01-01

    The sand fly Lutzomyia longipalpis (Diptera: Psychodidae: Phlebotominae), the most important vector of American visceral leishmaniasis, is widely distributed in Latin America. There is currently a consensus that it represents a species complex, however, the number and distribution of the different siblings is still uncertain. Previous analyses have indicated that Brazilian populations of this vector can be divided into two main groups according to the type of courtship song (Burst vs. Pulse) males produce during copulation. Nevertheless, no diagnostic differences have been observed between these two groups with most molecular markers used to date. We analyzed the molecular divergence in a fragment of the paralytic (para) gene, a locus involved in the control of courtship songs in Drosophila, among a number of Lu. longipalpis populations from Brazil producing Burst and Pulse-type songs. Our results revealed a very high level of divergence and fixed differences between populations producing the two types of songs. We also compared Lu. longipalpis with a very closely related species, Lutzomyia cruzi, which produces Burst-type songs. The results indicated a higher number of fixed differences between Lu. cruzi and the Pulse-type populations of Lu. longipalpis than with those producing Burst-type songs. The data confirmed our previous assumptions that the presence of different sibling species of the Lu. longipalpis complex in Brazil can be divided into two main groups, one representing a single species and a second more heterogeneous group that probably represents a number of incipient species. We hypothesize that para might be one of the genes directly involved in the control of the courtship song differences between these two groups or that it is linked to other loci associated with reproductive isolation of the Brazilian species. PMID:22970200

  9. Biodiversity and γ-Aminobutyric Acid Production by Lactic Acid Bacteria Isolated from Traditional Alpine Raw Cow’s Milk Cheeses

    Directory of Open Access Journals (Sweden)

    Elena Franciosi

    2015-01-01

    Full Text Available “Nostrano-cheeses” are traditional alpine cheeses made from raw cow’s milk in Trentino-Alto Adige, Italy. This study identified lactic acid bacteria (LAB developing during maturation of “Nostrano-cheeses” and evaluated their potential to produce γ-aminobutyric acid (GABA, an immunologically active compound and neurotransmitter. Cheese samples were collected on six cheese-making days, in three dairy factories located in different areas of Trentino and at different stages of cheese ripening (24 h, 15 days, and 1, 2, 3, 6, and 8 months. A total of 1,059 LAB isolates were screened using Random Amplified Polymorphic DNA-PCR (RAPD-PCR and differentiated into 583 clusters. LAB strains from dominant clusters (n=97 were genetically identified to species level by partial 16S rRNA gene sequencing. LAB species most frequently isolated were Lactobacillus paracasei, Streptococcus thermophilus, and Leuconostoc mesenteroides. The 97 dominant clusters were also characterized for their ability in producing GABA by high-performance liquid chromatography (HPLC. About 71% of the dominant bacteria clusters evolving during cheeses ripening were able to produce GABA. Most GABA producers were Lactobacillus paracasei but other GABA producing species included Lactococcus lactis, Lactobacillus plantarum, Lactobacillus rhamnosus, Pediococcus pentosaceus, and Streptococcus thermophilus. No Enterococcus faecalis or Sc. macedonicus isolates produced GABA. The isolate producing the highest amount of GABA (80.0±2.7 mg/kg was a Sc. thermophilus.

  10. Biogas - a contribution to solving the energy supply problem of cheese factories. Biogas - ein Beitrag zur Loesung des Energieversorgungsproblems der gewerblichen Kaesereien

    Energy Technology Data Exchange (ETDEWEB)

    Favre, R

    1984-01-01

    During a 2-years-monitoring period different types of biogas-plants installed in the cheese factories 'Giessen', 'Steinenbrugg', 'Niederstetten' and 'Bodmen' have been investigated. Piggeries with 400 to 700 finishing places were attached to these cheese factories. These four milk processing plants are representative of an average Swiss cheese factory processing 800,000 to 1,500,000 liters of milk a year. The investigations showed that the energy-demand of the cheese-factories is ideal for the use of biogas. The capacities of gas- and hot-water-storage can be planned with a minimum reserve because in most cases cheese fabrication takes place daily. Apart from the fabrication process, the residence of the cheese maker, the cheese cellar, the feed-preparation, the finishing building and the hot-water supply need heat. There are no longtime peak-demands. The swine manure, well qualified for biogas production, is digested during a retention time of 2 to 10 weeks. The plants are heated with biogas excepted the one installed in 'Bodmen'. The gas yield of the mesophilic working flow-plants reaches 0.4 (Nm/sup 3//kgOS), which means the double value of the psychrophilic working storage plant 'Bodmen'. The plants in 'Giessen' and 'Steinenbrugg' need 20 to 40 (%) of the gas-production for their reactor-heating. Therefore the net gas-production of all four plants remained nearly identic. In all cheese-factories the biogas is burned for the heat-supply. The biogas covered of the total energy demand in the average 40 (%) in 'Steinenbrugg', 60 (%) in 'Niederstetten' and 33 (%) in 'Bodmen'. In 'Giessen' the rate was lower due to biogas-tests. An imaginary cheese-factory in the size of 'Giessen' equipped with a total energy-modul (gas-motor, generator, heat-pump) was tested by ENSIM. The result proofed that an energy autarcy is possible due to an enormeous technical installation.

  11. Pneumococcal infections in humans are associated with increased apoptosis and trafficking of type 1 cytokine-producing T cells

    DEFF Research Database (Denmark)

    Kemp, Kåre; Bruunsgaard, Helle; Skinhøj, Peter

    2002-01-01

    , little is known regarding the T-cell response during in vivo infections in humans. The purpose of this study was to test the hypothesis that activated T cells producing type 1 cytokines were engaged in the host response to pneumococcal infections. The phenotype and function of T cells were studied in 22...

  12. Production of farmstead lactose-free Pecorino di Osilo and ricotta cheeses from sheep’s milk

    Directory of Open Access Journals (Sweden)

    Luisa Pulinas

    2017-02-01

    Full Text Available The present work was aimed to define and validate farmstead production of lactose- free Pecorino di Osilo cheese, fresh ricotta cheese, and salted and smoked ricotta cheese (Ricotta mustia. The enzymatic activity of the commercial preparation containing lactase (1.1 g/mL, preliminarily tested using a spectrophotometric titration, showed activity equal to 4950±40 neutral lactase unit/g. The amount of lactase required to obtain the lactose-free milk was then established in triplicate laboratory trials, by adding the enzyme at concentrations of 0.7, 0.9 and 1.1 g/L in flasks containing 160 mL of raw sheep’s milk. Samples were incubated under conditions expected during milk storage and cheese-making. The residual lactose content in milk was determined by enzymatic method. The addition of lactase at concentration of 1.1 g/L of milk reduced the lactose concentration below the limit of detection (LOD of 0.06 g/L. The procedure was validated at a dairy farm, using three different batches of bulk raw sheep’s lactose-free milk that were transformed into Pecorino di Osilo cheese. The resulting whey was used to produce fresh ricotta and Ricotta mustia cheese. Raw milk and whey samples were always below lactose detection limit. The residual lactose was measured in Pecorino di Osilo cheese, after 24 hours and 30 days from production; in fresh ricotta cheese, after 48 hours; in Ricotta mustia cheese after 7 days. The determination of lactose content in cheese samples was conducted by a gas chromatography- flame ionization detection method, which showed a LOD and limit of quantification respectively of 1.8 and 5.6 mg/kg for cheese, and 1.35 and 4.2 mg/kg for both ricotta cheeses. The lactose concentration was always below the relevant LOD values in all samples. The mean concentration of galactose and glucose were respectively 13,000±2000 and 11,000±2000 mg/kg in fresh Pecorino di Osilo, 1100±300 and 1200±300 mg/kg in fresh ricotta, and 950±400 and 750

  13. Can pions created in high-energy heavy-ion collisions produce a Centauro-type effect?

    International Nuclear Information System (INIS)

    Martinis, M.; Mikuta-Martinis, V.; Crnugelj, J.

    1995-01-01

    We study a Centauro-type phenomenon in high-energy heavy-ion collisions by assuming that pions are produced semiclassically both directly and in pairs through the isovector channel. The leading-particle effect and the factorization property of the scattering amplitude in the impact-parameter space are used to define the classical pion field. We show that the Centauro-type effect is strongly suppressed if a large number of pions are produced in isovector pairs. Our conclusion is supported through the calculation of two pion correlation parameters, f 2 0- and f 2 00 , as well as f 2, n - 0 and the average number of neutral pions (left-angle n 0 right-angle n- ) a a function of negative pions (n - ) produced

  14. Antimicrobial effects of pepper, parsley, and dill and their roles in the microbiological quality enhancement of traditional Egyptian Kareish cheese.

    Science.gov (United States)

    Wahba, Nahed M; Ahmed, Amany S; Ebraheim, Zedan Z

    2010-04-01

    This study was designed to assess the application of some edible plants including cayenne, green pepper, parsley, and dill to Kareish cheese and to evaluate the antimicrobial activity of these plant materials against natural microflora, coliforms, molds, and Staphylococcus aureus. Twelve different concentrations of ethanol extract of the plants were prepared for determination of the minimal inhibitory concentration. Cayenne and green pepper extracts showed highest activity followed by dill and parsley against S. aureus. Addition of cayenne or green pepper to Kareish cheese during manufacture revealed that both plants were able reduce the S. aureus population to undetectable level within the first and second days of storage. To study the effect of combining plant materials on the microbiological quality of ready-to-eat Kareish cheese, the total bacterial count, coliform count, and yeast and molds counts were determined. It has been found that addition of plant materials to Kareish cheese reduced the total bacterial and coliform populations. All concentrations of cayenne, green pepper, dill, and parsley (9%) completely reduced the yeast count within 2 hours. Cayenne and green pepper completely reduced the mold count within 2 days, whereas parsley and dill were found to be less effective. Kareish cheese prepared with 1% cayenne pepper and 3% and 6% each of green pepper, dill, and parsley were found strongly acceptable to the consumer and considered the most preferable type. Therefore, this study revealed that pepper, parsley, and dill exhibited antibacterial activity against natural microflora, coliforms, yeast and molds, and S. aureus in Kareish cheese, and the addition of these plants is acceptable to the consumer and may contribute to the development of new and safe varieties of Kareish cheese.

  15. Development of technology for production of reduced fat processed cheese

    Directory of Open Access Journals (Sweden)

    Adriana Torres Silva e Alves

    2015-09-01

    Full Text Available An increasing share of foods with reduced fat has been observed in the diet of the Brazilian population, a trend also seen in many other countries. In this context, our-aim was to study the manufacturing parameters and to develop a process to produce a spreadable processed cheese (requeijão cremoso with reduced fat content. In the first stage of this study, modifications were performed in the traditional manufacturing process of requeijão cremoso with regular fat content to produce a reduced fat product. During the second stage of this study, two reduced fat cheeses, with and withoutthe addition of whey protein concentrate (WPC were developed, both using JOHA S9 and JOHA PZ as emulsifying salts, resulting in four different formulations. The amounts of cream and water used in both products were calculated in order to obtain a final product with 10% fat and 33% total solids. The product which presented the best results was produced with curd obtained by direct acidification of skimmed milk heated at 68-70 ºC, using 1,3% emulsifying salt JOHA S9 in the melting process and 2% WPC 34% as a partial fat substitute, both calculated as a percentage of the amountof curd used as raw material. It was also important to add WPC 34% to the product at the first cooking step of the process (70 ºC, in order to obtain a final product withthe typical spreadable texture of the traditional requeijão cremoso.

  16. Locally Reinforcement TiC-Fe Type Produced in Situ in Castings

    Directory of Open Access Journals (Sweden)

    Olejnik E.

    2016-09-01

    Full Text Available Refinement is one of the most energy consuming technological process, aimed at obtaining mineral raw materials of the proper grain size. Cast structural elements such as jaws or hammers in crushing machines operate under conditions of an intensive wear. The data indicate that 80 % of failures of machines and devices is caused by wearing of rubbing surfaces. This problem became the subject of several scientific and industrial investigations carried out in the whole world in order to produce materials ultra- wear resistant. Methods allowing to obtain wear resistant composite castings are discussed in the hereby paper. Within the performed research microstructures of the produced composite zones were presented and the comparative analysis with regard to mechanical and functional properties of local composite reinforcements in relation to the commercial alloys of increased wear resistance was performed. The results show almost twenty five times increase in wear resistance compared to manganese cast steel containing 18 % Mn.

  17. Producing p-type conductivity in self-compensating semiconductor material

    International Nuclear Information System (INIS)

    Vechten, J.A. van; Woodall, J.M.

    1981-01-01

    This relates to compound type semiconductor materials that exhibit self-compensated n-type conductivity. The process described imparts p-type conductivity to a body of normally n-conductivity self-compensated compound semiconductor material by bombarding it with charged particles, either electrons, protons or ions. Other possible steps include introducing an acceptor impurity and applying a coating onto the crystal body. This technique will allow new semiconductor structures to be made. For example, there are some compound semiconductor materials that exhibit n-conductivity only that have energy gap widths that would permit electrical to light conversion at frequency and colours not readily achieved in semiconductor devices. (U.K.)

  18. Effect of Persian and almond gums as fat replacers on the physicochemical, rheological, and microstructural attributes of low-fat Iranian White cheese.

    Science.gov (United States)

    Jooyandeh, Hossein; Goudarzi, Mostafa; Rostamabadi, Hadis; Hojjati, Mohammad

    2017-05-01

    The effect of Persian and almond gums (0, 0.1 and 0.2% (w/w)) as fat replacers and milk fat (0.4, 0.9, and 1.4% (w/w)) on physicochemical and rheological characteristics and microstructure of low-fat Iranian White cheese was studied. Persian and almond gums both effectively increased moisture-to-protein (M:P) ratio of low-fat cheese samples which in turn led to a significant reduction in the hardness parameters fracture stress and Young's and storage (G') moduli ( p  Persian gum was more pronounced ( p  Persian gum and 0.12% almond gum would result in a low-fat cheese with textural properties similar to its full-fat counterpart. Scanning electron microscopy revealed that the fat replacers produced full-fat-like structure in the low-fat Iranian White cheese, when incorporated at the optimum levels.

  19. Analysis of neutral volatile aroma components in Tilsit cheese using a combination of dynamic headspace technique, capillary gas chromatography and mass spectrometry

    International Nuclear Information System (INIS)

    Dillinger, K.H.

    2000-03-01

    Tilsit cheese is made by the influence of lab ferment and starter cultures on milk. The ripening is done by repeated inoculation of the surface of the Tilsit cheese with yeasts and read smear cultures. This surface flora forms the typical aroma of the Tilsit cheese during the ripening process. The aim of the work was to receive general knowledge about the kind and amount of the neutral volatile aroma components of Tilsit cheese. Beyond this the ability of forming aroma components by read smear cultures and the dispersion of these components in cheese was to be examined. The results were intended to evaluate the formation of aroma components in Tilsit cheese. The semi-quantitative analyses of the aroma components of all samples were done by combining dynamic headspace extraction, gas chromatography and mass spectrometry. In this process the neutral volatile aroma components were extracted by dynamic headspace technique, adsorbed on a trap, thermally desorbed, separated by gas chromatography, detected and identified by mass spectrometry. 63 components belonging to the chemical classes of esters, ketones, aldehydes, alcohols and sulfur containing substances as well as aromatic hydrocarbons, chlorinated hydrocarbons and hydrocarbons were found in the analysed cheese samples of different Austrian Tilsit manufacturing plants. All cheese samples showed a qualitative equal but quantitative varied spectrum of aroma components. The cultivation of pure cultures on a cheese agar medium showed all analysed aroma components to be involved in the biochemical metabolism of these cultures. The ability to produce aroma components greatly differed between the strains and it was not possible to correlate this ability with the taxonomic classification of the strains. The majority of the components had a non-homogeneous concentration profile in the cheese body. This was explained by effects of diffusion and temporal and spatial different forming of components by the metabolism of the

  20. Amino acid catabolism by Lactobacillus helveticus in cheese

    DEFF Research Database (Denmark)

    Kananen, Soila Kaarina

    Amino acid catabolism is the final step in the conversion of caseins to flavour compounds and a part of a complex combination of biochemical pathways in cheese flavour formation. Lactobacillus helveticus is a thermophilic lactic acid bacterium that is used in cheese manufacture as a primary starter...... culture or as an adjunct culture. It has shown high proteolytic activities in conversion of caseins to peptides and further to amino acids and flavour compounds. Better understanding of the enzyme activity properties and the influence of different properties on final cheese flavour is favourable...... for developing new cheese products with enhanced flavour. The aim of this Ph.D. study was to investigate the importance of strain variation of Lb. helveticus in relation flavour formation in cheese related to amino acid catabolism. Aspects of using Lb. helveticus as starter as well as adjunct culture in cheese...

  1. Response of Edam cheese to non-destructive impact

    Directory of Open Access Journals (Sweden)

    Šárka Nedomová

    2009-01-01

    Full Text Available The behaviour of the Edam cheese during its maturation under dynamic loading has been studied. The block of tested cheese has been loaded by the impact of an aluminium bar. The force between bar and cheese has been recorded. The surface displacements as well as the surface velocities have been obtained at the different points from the point of the bar impact using of the laser vibrometers. Response functions have been evaluated both in the time and frequency domains. It has been found that the degree of the cheese maturity is well characterized by the attenuation of the surface displacement maximum. This maturation is also described by the maximum of the impact force. The spectral analysis of the response functions revealed that there was a dominant frequency, which depends only on the degree of the cheese maturity. The developed method represents a promising procedure for the continuous recording of the cheese ripening.

  2. An assessment of iodine in cheese in Macedonia

    International Nuclear Information System (INIS)

    Bogdanov, Bogdan; Gonev, Mihail; Tadzher, Isak S.

    1998-01-01

    We assessed some products in Macedonian food containing iodine: milk, bread, eggs, iodized salt. These nutritional items are deficient in iodine compared to western technology of,food preparation. Cheese prepared as white cheese from sheep and cow's milk is a much-used nutritional product. According to the Central Macedonian Statistical Bureau at the. Ministry of Health the laboratory measured iodine dosage in order to have an estimation of what the contribution of cheese is in the daily Macedonian diet. The collection of cheese was independently performed by the food inspectors in all regions of Macedonia. In June 1998 all specimens were in the laboratory. Macedonian white cheese has 57 micro g/dl iodine. In comparison to other nutritional items as milk, eggs and bread with a low contingent of iodine, the Macedonian cheese covers a good part of daily iodine necessity. We present our results with a brief comment on iodine metabolism. (Original)

  3. Microbiological quality of sliced and block mozzarella cheese

    Directory of Open Access Journals (Sweden)

    Mariana Fontanetti Marinheiro

    2015-06-01

    Full Text Available The aim of this study was to verify the microbiological quality of mozzarella cheese sold in retail markets of Pelotas, Rio Grande do Sul, Brazil. Forty samples of mozzarella cheese were analyzed, comprising 20 samples of block cheese and 20 of sliced cheese. The cheese samples were analyzed for thermotolerant coliform counts and coagulase positive staphylococci counts, and presence of Salmonella spp and Listeria monocytogenes. The percentage of 12,5% and 5% of the sliced and block cheese samples analyzed, respectively, exceeded the microbiological standards accepted by Brazilian legislation. These results indicate the need for a better product monitoring and more concern with hygiene and sanitary practices during industrial process.

  4. Forecasting fluid milk and cheese demands for the next decade.

    Science.gov (United States)

    Schmit, T M; Kaiser, H M

    2006-12-01

    Predictions of future market demands and farm prices for dairy products are important determinants in developing marketing strategies and farm-production planning decisions. The objective of this report was to use current aggregate forecast data, combined with existing econometric models of demand and supply, to forecast retail demands for fluid milk and cheese and the supply and price of farm milk over the next decade. In doing so, we can investigate whether projections of population and consumer food-spending patterns will extend or alter current consumption trends and examine the implications of future generic advertising strategies for dairy products. To conduct the forecast simulations and appropriately allocate the farm milk supply to various uses, we used a partial equilibrium model of the US domestic dairy sector that segmented the industry into retail, wholesale, and farm markets. Model simulation results indicated that declines in retail per capita demand would persist but at a reduced rate from years past and that retail per capita demand for cheese would continue to grow and strengthen over the next decade. These predictions rely on expected changes in the size of populations of various ages, races, and ethnicities and on existing patterns of spending on food at home and away from home. The combined effect of these forecasted changes in demand levels was reflected in annualized growth in the total farm-milk supply that was similar to growth realized during the past few years. Although we expect nominal farm milk prices to increase over the next decade, we expect real prices (relative to assumed growth in feed costs) to remain relatively stable and show no increase until the end of the forecast period. Supplemental industry model simulations also suggested that net losses in producer revenues would result if only nominal levels of generic advertising spending were maintained in forthcoming years. In fact, if real generic advertising expenditures are

  5. Sensory shelf life of mantecoso cheese using accelerated testing

    OpenAIRE

    Sánchez-González, Jesús A.; Pérez, Joel A.

    2016-01-01

    The aim of this research was to estimate sensory shelf life of "huacariz" and "cefop" mantecoso cheese, vacuum packaging: "cefop" and packaging to the atmospheric pressure: "huacariz"; brands marketed in Cajamarca, using accelerated shelf life testing. For this purpose, "huacariz" cheese was stored at 20, 28, 35 y 40 °C, while it was set at 20, 28, 35 °C storage for "cefop" cheese, performing acceptability sensory tests according to time storage with both 41 consumers constants. The results f...

  6. 7 CFR 58.439 - Cheese from unpasteurized milk.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Cheese from unpasteurized milk. 58.439 Section 58.439... Procedures § 58.439 Cheese from unpasteurized milk. If the cheese is labeled as “heat treated”, “unpasteurized,” “raw milk”, or “for manufacturing” the milk may be raw or heated at temperatures below...

  7. Cheese Consumption and Risk Factors for Cardiovascular Disease and the Metabolic Syndrome

    DEFF Research Database (Denmark)

    Raziani, Farinaz

    -fat cheese for 12 weeks did not modify LDL-C concentrations or MetS risk factors differently than equal amounts of reduced-fat cheese. The same was true when regular-cheese was compared with carbohydrate-rich foods, although regular-fat cheese tended to increase HDL-C concentrations compared...... that lipoprotein response is gender-specific. In men, regular-fat cheese intake reduced total LDL particle number compared with reduced-fat cheese, whereas regular-fat cheese consumption tended to increase total LDL particle number compared with reduced-fat cheese in women. Overall, the data from the large human...

  8. Aping expressions? Chimpanzees produce distinct laugh types when responding to laughter of others.

    Science.gov (United States)

    Davila-Ross, Marina; Allcock, Bethan; Thomas, Chris; Bard, Kim A

    2011-10-01

    Humans have the ability to replicate the emotional expressions of others even when they undergo different emotions. Such distinct responses of expressions, especially positive expressions, play a central role in everyday social communication of humans and may give the responding individuals important advantages in cooperation and communication. The present work examined laughter in chimpanzees to test whether nonhuman primates also use their expressions in such distinct ways. The approach was first to examine the form and occurrence of laugh replications (laughter after the laughter of others) and spontaneous laughter of chimpanzees during social play and then to test whether their laugh replications represented laugh-elicited laugh responses (laughter triggered by the laughter of others) by using a quantitative method designed to measure responses in natural social settings. The results of this study indicated that chimpanzees produce laugh-elicited laughter that is distinct in form and occurrence from their spontaneous laughter. These findings provide the first empirical evidence that nonhuman primates have the ability to replicate the expressions of others by producing expressions that differ in their underlying emotions and social implications. The data further showed that the laugh-elicited laugh responses of the subjects were closely linked to play maintenance, suggesting that chimpanzees might gain important cooperative and communicative advantages by responding with laughter to the laughter of their social partners. Notably, some chimpanzee groups of this study responded more with laughter than others, an outcome that provides empirical support of a socialization of expressions in great apes similar to that of humans.

  9. Survival of probiotic adjunct cultures in cheese and challenges in their enumeration using selective media.

    Science.gov (United States)

    Oberg, C J; Moyes, L V; Domek, M J; Brothersen, C; McMahon, D J

    2011-05-01

    Various selective media for enumerating probiotic and cheese cultures were screened, with 6 media then used to study survival of probiotic bacteria in full-fat and low-fat Cheddar cheese. Commercial strains of Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus paracasei, or Bifidobacterium lactis were added as probiotic adjuncts. The selective media, designed to promote growth of certain lactic acid bacteria (LAB) over others or to differentiate between LAB, were used to detect individual LAB types during cheese storage. Commercial strains of Lactococcus, Lactobacillus, and Bifidobacterium spp. were initially screened on the 6 selective media along with nonstarter LAB (NSLAB) isolates. The microbial flora of the cheeses was analyzed during 9 mo of storage at 6°C. Many NSLAB were able to grow on media presumed selective for Lactococcus, Bifidobacterium spp., or Lb. acidophilus, which became apparent after 90 d of cheese storage, Between 90 and 120 d of storage, bacterial counts changed on media selective for Bifidobacterium spp., suggesting growth of NSLAB. Appearance of NSLAB on Lb. casei selective media [de man, Rogosa, and Sharpe (MRS)+vancomycin] occurred sooner (30 d) in low-fat cheese than in full-fat control cheeses. Differentiation between NSLAB and Lactococcus was achieved by counting after 18 to 24h when the NSLAB colonies were only pinpoint in size. Growth of NSLAB on the various selective media during aging means that probiotic adjunct cultures added during cheesemaking can only be enumerated with confidence on selective media for up to 3 or 4 mo. After this time, growth of NSLAB obfuscates enumeration of probiotic adjuncts. When adjunct Lb. casei or Lb. paracasei cultures are added during cheesemaking, they appear to remain at high numbers for a long time (9 mo) when counted on MRS+vancomycin medium, but a reasonable probability exists that they have been overtaken by NSLAB, which also grow readily on this medium. Enumeration using multiple

  10. Growth, survival, and peptidolytic activity of Lactobacillus plantarum I91 in a hard-cheese model.

    Science.gov (United States)

    Bergamini, C V; Peralta, G H; Milesi, M M; Hynes, E R

    2013-09-01

    In this work, we studied the growth, survival, and peptidolytic activity of Lactobacillus plantarum I91 in a hard-cheese model consisting of a sterile extract of Reggianito cheese. To assess the influence of the primary starter and initial proteolysis level on these parameters, we prepared the extracts with cheeses that were produced using 2 different starter strains of Lactobacillus helveticus 138 or 209 (Lh138 or Lh209) at 3 ripening times: 3, 90, and 180 d. The experimental extracts were inoculated with Lb. plantarum I91; the control extracts were not inoculated and the blank extracts were heat-treated to inactivate enzymes and were not inoculated. All extracts were incubated at 34°C for 21 d, and then the pH, microbiological counts, and proteolysis profiles were determined. The basal proteolysis profiles in the extracts of young cheeses made with either strain tested were similar, but many differences between the proteolysis profiles of the extracts of the Lh138 and Lh209 cheeses were found when riper cheeses were used. The pH values in the blank and control extracts did not change, and no microbial growth was detected. In contrast, the pH value in experimental extracts decreased, and this decrease was more pronounced in extracts obtained from either of the young cheeses and from the Lh209 cheese at any stage of ripening. Lactobacillus plantarum I91 grew up to 8 log during the first days of incubation in all of the extracts, but then the number of viable cells decreased, the extent of which depended on the starter strain and the age of the cheese used for the extract. The decrease in the counts of Lb. plantarum I91 was observed mainly in the extracts in which the pH had diminished the most. In addition, the extracts that best supported the viability of Lb. plantarum I91 during incubation had the highest free amino acids content. The effect of Lb. plantarum I91 on the proteolysis profile of the extracts was marginal. Significant changes in the content of free

  11. In vitro screening of potential probiotic activities of selected lactobacilli isolated from unpasteurized milk products for incorporation into soft cheese.

    Science.gov (United States)

    Coeuret, Valérie; Gueguen, Micheline; Vernoux, Jean Paul

    2004-11-01

    The aim was to select potentially probiotic lactobacilli from 88 strains isolated from unpasteurized milk and cheese products, and to incorporate these bacteria in a viable state into a soft cheese, without changing its quality. The survival of these bacteria was assessed in acidic and bile conditions, after freezing at -80 degrees C. Four strains from unpasteurized Camembert--two Lactobacillus plantarum strains and two Lb. paracasei/casei strains--were identified and typed by PCR and PFGE and were found to display potentially probiotic characteristics in addition to resistance to low pH and bile. These characteristics were resistance to lysozyme, adhesion to CACO-2 cells, antimicrobial effects against common foodborne pathogens (Listeria monocytogenes, Staphylococcus aureus, Salmonella spp., Escherichia coli, innocuity following the ingestion of high doses by mice and appropriate antibiotic susceptibility profiles. The potential of Lb. plantarum strain UCMA 3037 for incorporation into a soft cheese (Pont-l'Eveque registered designation of origin (RDO)) was investigated. This strain grew well and survived in sufficient numbers (more than 10(7) cfu/g throughout the shelf-life of the product) in the cheese. This strain did not change the quality score of the product until the best before date (75 days after manufacture). Thus, unpasteurized Camembert is a natural source of potentially probiotic lactobacilli, which could be used as an additive in the development of potentially probiotic soft cheeses. Further work is required to demonstrate the persistence and efficacy of these strains in the human host upon ingestion.

  12. Technical Appraisal of Continuous Destilator Type as Alternative Fuel Producer from Basic Materials of Arak Bali

    Directory of Open Access Journals (Sweden)

    Sukadana -

    2012-11-01

    Full Text Available Arrack Bali which is produced from traditional process has low quality (<40%. With controlling of operational variable such as evaporation temperature, will improve arrack Bali quality. Arrack Bali with quality more than 80 % has octane number more than 108,6, higher then petroleum octane number (80 until 90, easy burning and evaporation, very good to be alternative fuel to engine. In order to product height quality any operational variables like temperature, step, and sprayer models should be noticed. This experiment is to obtain operational variables of distillatory to product arrack Bali as an alternative fuel and it is tested in motor cycle engine at speed and compression ratio variables toward performance like emission. The higher evaporation temperature is the higher capacity of product to be obtained, on the other hand, the lower quality to be reached. Generally, comparing with petroleum, arrack Bali yields lower emission.

  13. cis-fumagillin, a new methionine aminopeptidase (type 2) inhibitor produced by Penicillium sp. F2757.

    Science.gov (United States)

    Kwon, J Y; Jeong, H W; Kim, H K; Kang, K H; Chang, Y H; Bae, K S; Choi, J D; Lee, U C; Son, K H; Kwon, B M

    2000-08-01

    Selective inhibition against the yeast MetAP2 (methionine aminopeptidase type 2) was detected in the fermentation broth of a fungus F2757 that was later identified as Penicillium janczewskii. A new compound cis-fumagillin methyl ester (1) was isolated from the diazomethane treated fermentation extracts together with the known compound fumagillin methyl ester (2). The cis-fumagillin methyl ester, a stereoisomer of fumagillin methyl ester at the C2'-C3' position of the aliphatic side chain, selectively inhibited growth of the map1 mutant yeast strain (MetAP1 deletion strain) at a concentration as low as 1 ng. However, the wild type yeast w303 and the mutant map2 (MetAP2 deleted) strains were resistant up to 10 microg of the compound. In enzyme experiments, compound 1 inhibited the MetAP2 with an IC50 value of 6.3 nM, but it did not inhibit the MetAP1 (IC50 >200 microM). Compound 2 also inhibited the MetAP2 with an IC50 value of 9.2 nM and 105 microM against MetAP1.

  14. PPAR-δ Agonist With Mesenchymal Stem Cells Induces Type II Collagen-Producing Chondrocytes in Human Arthritic Synovial Fluid.

    Science.gov (United States)

    Heck, Bruce E; Park, Joshua J; Makani, Vishruti; Kim, Eun-Cheol; Kim, Dong Hyun

    2017-08-01

    Osteoarthritis (OA) is an inflammatory joint disease characterized by degeneration of articular cartilage within synovial joints. An estimated 27 million Americans suffer from OA, and the population is expected to reach 67 million in the United States by 2030. Thus, it is urgent to find an effective treatment for OA. Traditional OA treatments have no disease-modifying effect, while regenerative OA therapies such as autologous chondrocyte implantation show some promise. Nonetheless, current regenerative therapies do not overcome synovial inflammation that suppresses the differentiation of mesenchymal stem cells (MSCs) to chondrocytes and the expression of type II collagen, the major constituent of functional cartilage. We discovered a synergistic combination that overcame synovial inflammation to form type II collagen-producing chondrocytes. The combination consists of peroxisome proliferator-activated receptor (PPAR) δ agonist, human bone marrow (hBM)-derived MSCs, and hyaluronic acid (HA) gel. Interestingly, those individual components showed their own strong enhancing effects on chondrogenesis. GW0742, a PPAR-δ agonist, greatly enhanced MSC chondrogenesis and the expression of type II collagen and glycosaminoglycan (GAG) in hBM-MSC-derived chondrocytes. GW0742 also increased the expression of transforming growth factor β that enhances chondrogenesis and suppresses cartilage fibrillation, ossification, and inflammation. HA gel also increased MSC chondrogenesis and GAG production. However, neither GW0742 nor HA gel could enhance the formation of type II collagen-producing chondrocytes from hBM-MSCs within human OA synovial fluid. Our data demonstrated that the combination of hBM-MSCs, PPAR-δ agonist, and HA gel significantly enhanced the formation of type II collagen-producing chondrocytes within OA synovial fluid from 3 different donors. In other words, the novel combination of PPAR-δ agonist, hBM-MSCs, and HA gel can overcome synovial inflammation to form

  15. Differentiation and distribution of three types of exfoliative toxin produced by Staphylococcus hyicus from pigs with exudative epidermitis

    DEFF Research Database (Denmark)

    Andresen, Lars Ole

    1998-01-01

    were antigenically distinct. The three toxins were designated ExhA, ExhB and ExhC. From 60 diseased pigs, each representing an outbreak of exudative epidermitis, a total of 584 isolates of S. hl icus were phage typed and tested for production of exfoliative toxin. ExhA-, ExhB- and ExhC-producing S....... hyicus isolates were found in 12 (20%), 20 (33%) and 11 (18%); respectively, of the 60 pig herds investigated. Production of the different types of exfoliative toxin was predominantly associated with certain phage groups. However. toxin production was found in all of the six phage groups defined...

  16. Development of a typing system for epidemiological studies of porcine toxin-producing Pasteurella multocida ssp. multocida in Denmark

    DEFF Research Database (Denmark)

    Fussing, V.; Nielsen, Jens; Bisgaard, M.

    1999-01-01

    The aim of the present study was to evaluate capsular-typing, plasmid-profiling, phage-typing and ribotyping for epidemiological studies of toxin-producing Pasteurella multocida ssp. multocida in Denmark. The evaluation of methods was based on 68 strains from nasal swabs and 14 strains from...... by HindIII ribotyping, as 85% of isolates from all herds were assigned to one ribotype. In conclusion, HindIII ribotyping seems to represent a useful tool for epidemiological studies of toxigenic P. multocida ssp. multocida....

  17. Outbreak of OXA-48-Producing Klebsiella pneumoniae Involving a Sequence Type 101 Clone in Batna University Hospital, Algeria.

    Science.gov (United States)

    Loucif, Lotfi; Kassah-Laouar, Ahmed; Saidi, Mahdia; Messala, Amina; Chelaghma, Widad; Rolain, Jean-Marc

    2016-12-01

    Seven nonredundant ertapenem-resistant Klebsiella pneumoniae isolates were collected between May 2014 and 19 January 2015 in the nephrology and hematology units of Batna University Hospital in Algeria. All strains coproduced the bla OXA-48 , bla CTX-M-15 , bla SHV-1 , and bla TEM-1D genes. Six of these isolates belonged to the pandemic clone sequence type 101 (ST101). The bla OXA-48 gene was located on a conjugative IncL/M-type plasmid. This is the first known outbreak of OXA-48-producing K. pneumoniae isolates involving an ST101 clone in Batna University Hospital. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  18. Crystallization and preliminary crystallographic analysis of an acridone-producing novel multifunctional type III polyketide synthase from Huperzia serrata

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Hiroyuki [Mitsubishi Kagaku Institute of Life Sciences (MITILS), 11 Minamiooya, Machida, Tokyo 194-8511 (Japan); Kondo, Shin; Kato, Ryohei [Innovation Center Yokohama, Mitsubishi Chemical Corporation, 1000 Kamoshida, Aoba, Yokohama, Kanagawa 227-8502 (Japan); Wanibuchi, Kiyofumi; Noguchi, Hiroshi [School of Pharmaceutical Sciences, University of Shizuoka and the COE21 Program, Shizuoka 422-8526 (Japan); Sugio, Shigetoshi [Innovation Center Yokohama, Mitsubishi Chemical Corporation, 1000 Kamoshida, Aoba, Yokohama, Kanagawa 227-8502 (Japan); Abe, Ikuro [School of Pharmaceutical Sciences, University of Shizuoka and the COE21 Program, Shizuoka 422-8526 (Japan); PRESTO, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012 (Japan); Kohno, Toshiyuki [Mitsubishi Kagaku Institute of Life Sciences (MITILS), 11 Minamiooya, Machida, Tokyo 194-8511 (Japan)

    2007-07-01

    An acridone-producing novel type III polyketide synthase from H. serrata has been overexpressed in E. coli, purified and crystallized. Diffraction data have been collected to 2.0 Å. Polyketide synthase 1 (PKS1) from Huperzia serrata is a plant-specific type III polyketide synthase that shows an unusually versatile catalytic potential, producing various aromatic tetraketides, including chalcones, benzophenones, phlorogulucinols and acridones. Recombinant H. serrata PKS1 expressed in Escherichia coli was crystallized using the hanging-drop vapour-diffusion method. The crystals belonged to space group I222 or I2{sub 1}2{sub 1}2{sub 1}, with unit-cell parameters a = 73.3, b = 85.0, c = 137.7 Å, α = β = γ = 90.0°. Diffraction data were collected to 2.0 Å resolution using synchrotron radiation at BL24XU of SPring-8.

  19. Produce of seedlings of cedar in function of types of container and fertilization sources

    Directory of Open Access Journals (Sweden)

    Osmar Henrique de Castro Pias

    2015-06-01

    Full Text Available The aim of this study was to evaluate the production of cedar seedlings according to the size of containers and nutrient sources. It was tested three types of containers (Root trainers, plastic bag and plastic vase, three sources of fertilization (Conventional, Kimcoat® and Osmocote® in seven evaluations. The cedar seedlings in root trainers, fertilized with source Osmocote® presented the greatest increments in height and stem diameter when compared to another sources of fertilization. The plastic bag and plastic vase containers promoted similar seedlings height growth. However the seedlings grown in plastic vase presented greatest growth in stem diameter when compared with the ones in plastic bag.

  20. A unique cabling designed to produce Rutherford-type superconducting cable for the SSC project

    International Nuclear Information System (INIS)

    Grisel, J.; Royet, J.M.; Scanlan, R.M.; Armer, R.

    1988-08-01

    Up to 25,000 Km of keystoned flat cable must be produced for the SSC project. Starting from a specification developed by Lawrence Berkeley Laboratory (LBL), a special cabling machine has been designed by Dour Metal. It has been designed to be able to run at a speed corresponding to a maximum production rate of 10 m/min. This cabling machine is the key part of the production line which consists of a precision Turkshead equipped with a variable power drive, a caterpillar, a dimensional control bench, a data acquisition system, and a take-up unit. The main features of the cabling unit to be described are a design with nearly equal path length between spool and assembling point for all the wires, and the possibility to run the machine with several over- or under-twisting ratios between cable and wires. These requirements led Dour Metal to the choice of an unconventional mechanical concept for a cabling machine. 4 refs., 2 figs

  1. Paenibacillus polymyxa PKB1 produces variants of polymyxin B-type antibiotics.

    Science.gov (United States)

    Shaheen, Mohamed; Li, Jingru; Ross, Avena C; Vederas, John C; Jensen, Susan E

    2011-12-23

    Polymyxins are cationic lipopeptide antibiotics active against many species of Gram-negative bacteria. We sequenced the gene cluster for polymyxin biosynthesis from Paenibacillus polymyxa PKB1. The 40.8 kb gene cluster comprises three nonribosomal peptide synthetase-encoding genes and two ABC transporter-like genes. Disruption of a peptide synthetase gene abolished all antibiotic production, whereas deletion of one or both transporter genes only reduced antibiotic production. Computational analysis of the peptide synthetase modules suggested that the enzyme system produces variant forms of polymyxin B (1 and 2), with D-2,4-diaminobutyrate instead of L-2,4-diaminobutyrate in amino acid position 3. Two antibacterial metabolites were resolved by HPLC and identified by high-resolution mass spectrometry and MS/MS sequencing as the expected variants 3 and 4 of polymyxin B(1) (1) and B(2) (2). Stereochemical analysis confirmed the presence of both D-2,4-diaminobutyrate and L-2,4-diaminobutyrate residues. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Fenofibrate plus Metformin Produces Cardioprotection in a Type 2 Diabetes and Acute Myocardial Infarction Model

    Directory of Open Access Journals (Sweden)

    Víctor Hugo Oidor-Chan

    2016-01-01

    Full Text Available We investigated whether fenofibrate, metformin, and their combination generate cardioprotection in a rat model of type 2 diabetes (T2D and acute myocardial infarction (AMI. Streptozotocin-induced diabetic- (DB- rats received 14 days of either vehicle, fenofibrate, metformin, or their combination and immediately after underwent myocardial ischemia/reperfusion (I/R. Fenofibrate plus metformin generated cardioprotection in a DBI/R model, reported as decreased coronary vascular resistance, compared to DBI/R-Vehicle, smaller infarct size, and increased cardiac work. The subchronic treatment with fenofibrate plus metformin increased, compared with DBI/R-Vehicle, total antioxidant capacity, manganese-dependent superoxide dismutase activity (MnSOD, guanosine triphosphate cyclohydrolase I (GTPCH-I expression, tetrahydrobiopterin : dihydrobiopterin (BH4 : BH2 ratio, endothelial nitric oxide synthase (eNOS activity, nitric oxide (NO bioavailability, and decreased inducible NOS (iNOS activity. These findings suggest that PPARα activation by fenofibrate + metformin, at low doses, generates cardioprotection in a rat model of T2D and AMI and may represent a novel treatment strategy to limit I/R injury in patients with T2D.

  3. The cooling time of white dwarfs produced from type Ia supernovae

    International Nuclear Information System (INIS)

    Meng Xiangcun; Yang Wuming; Li Zhongmu

    2010-01-01

    Type Ia supernovae (SNe Ia) play a key role in measuring cosmological parameters, in which the Phillips relation is adopted. However, the origin of the relation is still unclear. Several parameters are suggested, e.g. the relative content of carbon to oxygen (C/O) and the central density of the white dwarf (WD) at ignition. These parameters are mainly determined by the WD's initial mass and its cooling time, respectively. Using the progenitor model developed by Meng and Yang, we present the distributions of the initial WD mass and the cooling time. We do not find any correlation between these parameters. However, we notice that as the range of the WD's mass decreases, its average value increases with the cooling time. These results could provide a constraint when simulating the SN Ia explosion, i.e. the WDs with a high C/O ratio usually have a lower central density at ignition, while those having the highest central density at ignition generally have a lower C/O ratio. The cooling time is mainly determined by the evolutionary age of secondaries, and the scatter of the cooling time decreases with the evolutionary age. Our results may indicate that WDs with a long cooling time have more uniform properties than those with a short cooling time, which may be helpful to explain why SNe Ia in elliptical galaxies have a more uniform maximum luminosity than those in spiral galaxies. (research papers)

  4. Levels of cystathionine gamma lyase production by Geotrichum candidum in synthetic media and correlation with the presence of sulphur flavours in cheese.

    Science.gov (United States)

    Gente, Stéphanie; La Carbona, Stéphanie; Guéguen, Micheline

    2007-03-10

    Geotrichum candidum is a cheese-ripening agent with the potential to produce sulphur flavour compounds in soft cheeses. We aimed to develop an alternative test for predicting the aromatic (sulphur flavours) potential of G. candidum strains in soft cheese. Twelve strains of G. candidum with different levels of demethiolase activity (determined by a chemical method) in YEL-met (yeast extract, lactate methionine) medium were studied. We investigated cgl (cystathionine gamma lyase) gene expression after culture in three media - YEL-met, casamino acid and curd media - and then carried out sensory analysis on a Camembert cheese matrix. We found no correlation between demethiolase activity in vitro and cgl gene expression. Sensory analysis (detection of sulphur flavours) identified different aromatic profiles linked to cgl expression, but not to demethiolase activity. The RT-PCR technique described here is potentially useful for predicting the tendency of a given strain of G. candidum to develop sulphur flavours in cheese matrix. This is the first demonstration that an in vitro molecular approach could be used as a predictive test for evaluating the potential of G. candidum strains to generate sulphur compounds in situ (Camembert cheese matrix).

  5. Acute hyperglycemia produces transient improvement in glucose transporter type 1 deficiency.

    Science.gov (United States)

    Akman, Cigdem I; Engelstad, Kristin; Hinton, Veronica J; Ullner, Paivi; Koenigsberger, Dorcas; Leary, Linda; Wang, Dong; De Vivo, Darryl C

    2010-01-01

    Glucose transporter type 1 deficiency syndrome (Glut1-DS) is characterized clinically by acquired microcephaly, infantile-onset seizures, psychomotor retardation, choreoathetosis, dystonia, and ataxia. The laboratory signature is hypoglycorrhachia. The 5-hour oral glucose tolerance test (OGTT) was performed to assess cerebral function and systemic carbohydrate homeostasis during acute hyperglycemia, in the knowledge that GLUT1 is constitutively expressed ubiquitously and upregulated in the brain. Thirteen Glut1-DS patients completed a 5-hour OGTT. Six patients had prolonged electroencephalographic (EEG)/video monitoring, 10 patients had plasma glucose and serum insulin measurements, and 5 patients had repeated measures of attention, memory, fine motor coordination, and well-being. All patients had a full neuropsychological battery prior to OGTT. The glycemic profile and insulin response during the OGTT were normal. Following the glucose load, transient improvement of clinical seizures and EEG findings were observed, with the most significant improvement beginning within the first 30 minutes and continuing for 180 minutes. Thereafter, clinical seizures returned, and EEG findings worsened. Additionally, transient improvement in attention, fine motor coordination, and reported well-being were observed without any change in memory performance. This study documents transient neurological improvement in Glut1-DS patients following acute hyperglycemia, associated with improved fine motor coordination and attention. Also, systemic carbohydrate homeostasis was normal, despite GLUT1 haploinsufficiency, confirming the specific role of GLUT1 as the transporter of metabolic fuel across the blood-brain barrier. The transient improvement in brain function underscores the rate-limiting role of glucose transport and the critical minute-to-minute dependence of cerebral function on fuel availability for energy metabolism.

  6. The Effect of Different Methods of Fermentation on the Detection of Milk Protein Residues in Retail Cheese by Enzyme-Linked Immunosorbent Assay (ELISA).

    Science.gov (United States)

    Ivens, Katherine O; Baumert, Joseph L; Hutkins, Robert L; Taylor, Steve L

    2017-11-01

    Milk and milk products are among the most important allergenic food ingredients, both in the United States and throughout the world; cheeses are among the most important of these milk products. Milk contains several major antigenic proteins, each with differing susceptibilities to proteolytic enzymes. The extent of proteolysis in cheese varies as a result of conditions during manufacture and ripening. Proteolysis has the potential to degrade antigenic and allergenic epitopes that are important for residue detection and elicitation of allergic reactions. Commercial enzyme-linked immunosorbent assays (ELISAs) are not currently validated for use in detecting residues in hydrolyzed or fermented food products. Eighteen retail cheeses produced using 5 different styles of fermentation were investigated for detectable milk protein residues with 4 commercial ELISA kits. Mozzarella, Swiss, Blue, Limburger, and Brie cheeses were assessed. The Neogen Veratox® Casein and Neogen Veratox® Total Milk kits were capable of detecting milk residues in most cheeses evaluated, including blue-veined cheeses that exhibit extensive proteolysis. The other 2 ELISA kits evaluated, r-Biopharm® Fast Casein and ELISA Systems™ Casein, can detect milk residues in cheeses other than blue-veined varieties. ELISA results cannot be quantitatively compared among kits. The quantitative reliability of ELISA results in detection of cheese residues is questionable, but some methods are sufficiently robust to use as a semi-quantitative indication of proper allergen control for the validation of cleaning programs in industry settings. Many commercially available enzyme-linked immunosorbent assays (ELISAs) are not validated for detection of allergenic residues in fermented or hydrolyzed products. This research seeks to determine if commercial milk ELISAs can detect milk residues in varieties of cheese that have undergone different styles of fermentation and different degrees of proteolysis. Only certain

  7. Yields of base damage products in crystalline DNA produced by the direct-type effect

    International Nuclear Information System (INIS)

    Gilbert, D.C.; Bernhard, W.A.; Swarts, S.G.

    2003-01-01

    Our aim is to determine the yields of base damage products due to direct-type effects in well-defined DNA samples. The sample, crystalline d(GCACGCGTGC) 2 , which contains Co(III), has been structurally characterized by others using X-ray crystallography and the free radical yields measured by our laboratory using EPR spectroscopy. Polycrystalline samples were x-irradiated (70 KeV) at room temperature (RT) to doses up to 150 kGy. Following dissolution under air, the base products were identified and quantified using GC-MS. 7,8-dihydro-8-oxoguanine (8-oxo-G) is the primary base damage product found, with a yield of ∼0.09 μmoles/J, whereas 2,6-diamino-4-oxo-5-formamidopyrimidine (FpyG) was below the limits of detection of the GC-MS assay. Radiation yields for 5,6-dihydrothymine (DHT) and 5-hydroxymethyluracil of 0.0017 and 0.0042 μmoles/J, respectively, were also observed. These results differ from those obtained in a previous study of solid-state hydrated DNA irradiated at RT (Swarts et al., Radiat. Res. 145: 304-14, 1996), where the yields of FpyG and DHT were approximately 11% and 20% that of 8-oxo-G, respectively. Our working hypothesis is that Co(III) in crystalline d(GCACGCGTGC) 2 modifies the product distribution. Based on the EPR data, the influence of Co(III) on the initial distribution of radical trapping is negligible. This suggests that electron transfer from the pyrimidines to Co(III) occurs either upon annealing and/or upon solvation, thereby competing with dihydropyrimidine formation. While strand break (sb) yields for d(GCACGCGTGC) 2 are not yet completed, in earlier work on crystals of other oligomers, we obtained sb yields of 0.06-0.16 μmoles/J. We anticipate, therefore, that the stoichiometry between 8-oxo-G and sb formation will be about 1:1

  8. Dynamics of lactose changes during ripening of Edam cheese

    Directory of Open Access Journals (Sweden)

    Lenka Vorlová

    2017-01-01

    lactose-free product whenever buying this type of cheese

  9. Physico-chemical and rheological properties of prato cheese during ...

    African Journals Online (AJOL)

    Aghomotsegin

    2015-06-17

    Jun 17, 2015 ... African Journal of Biotechnology. Full Length Research ... consumer usually evaluates the colour and aroma prior to ... parameters influence the texture of cheeses because the ... Quality of refrigerated milk used to process prato cheese ... Centre for Food Research of the School of Veterinary and Animal.

  10. Conditions allowing the formation of biogenic amines in cheese

    NARCIS (Netherlands)

    Joosten, H.M.L.J.

    1988-01-01

    A study was undertaken to reveal the conditions that allow the formation of biogenic amines in cheese.

    The starters most commonly used in the Dutch cheese industry do not have decarboxylative properties. Only if the milk or curd is contaminated with non-starter bacteria, amine

  11. Physiological characterization of common fungi associated with cheese

    DEFF Research Database (Denmark)

    Haasum, Iben; Nielsen, Per Væggemose

    1998-01-01

    A multivariate statistical method (PLS) was used for a physiological characterization of fungi associated with the cheese environment. The combined effects of pH, salt content, oxygen and carbon dioxide levels on growth and sporulation were studied. Significant factors affecting growth were salt...... may aid in eliminating unwanted fungal growth during cheese production....

  12. [Yeast microbiota in artisanal cheeses from Corrientes, Argentina].

    Science.gov (United States)

    Cardozo, Marina C; Fusco, Ángel J V; Carrasco, Marta S

    The artisanal cheese from Corrientes (from the Spanish acronym QAC-Queso Artesanal de Corrientes/Artisanal Cheese from Corrientes) is a soft cheese elaborated with raw cow milk and an artisanal coagulant agent. Lactic bacteria contitute the main flora of this cheese although yeasts are also present in high quantities as secondary microbiota and might play a relevant role in cheese ripening. The aim of this work was to evaluate yeast occurrence during QAC elaboration and ripening, and the effect of seasonal variation. Yeasts were isolated and purified from raw materials and cheese at different ripening stagesl elaborated during the different seasons. Yeast sample counts were in the order of 10 3 - 10 7 UFC/ml o UFC/g. Ninety yeast strains were classified: 9 from milk, 28 from the coagulant agent, 10 from curd and 43 from cheese. Candida predominated in milk samples while other yeast genera had low incidence. Candida also predominated in the coagulant agent samples, followed by genera Myxozyma and Debaryomyces. The isolates obtained from cheese belonged to the same genera predominating in the coagulant agent, and showed the same order of prevalence. Copyright © 2017 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  13. Comparative Evaluation of Cheese samples treated with Honey and ...

    African Journals Online (AJOL)

    The control treatment (A) was cheese kept in the whey, while Treatments B and C were cheese samples kept in Thyme and Honey solutions respectively. ... The crude protein was significantly higher (p<0.05) for Treatment B, then treatment A and least for treatment C. The ether extract followed the same trend as crude ...

  14. The use of spices in the production of traditional cheeses

    Directory of Open Access Journals (Sweden)

    Renata Josipović

    2016-01-01

    Full Text Available Cheese is a highly valued dairy product worldwide, with a special focus on traditional cheeses, not only for their basic nutritive purposes but also as a part of the culture and characteristics of a certain country. Owing to the geographical location as well as the climate and vegetation diversity, in certain regions of Croatia the production of various traditional cheeses using spices was developed. Spices are either added to the cheese curd which is then formed, or cheese is wrapped into plant leaves. Sometimes spices are also applied onto the surface of the cheese, and only in rare cases spices are added into the curd. Spices added to cheese improve sensory characteristics, increase the stability and shelf life but also increase the nutritional value. The chemical composition of spices is very complex and every spice has a specific and dominant ingredient that contributes to the flavour of the product and/or its antimicrobial and antioxidant activity. This paper provides an overview of spices and aromatic herbs as natural preservatives that are used in the production of traditional cheeses.

  15. PROTEIN & SENSORY ANALYSIS TO CHARACTERIZE MEXICAN CHIHUAHUA CHEESES

    Science.gov (United States)

    It has been established that native microflora in raw milk cheeses, including Queso Chihuahua, a Mexican cheese variety, contributes to the development of unique flavors through degradation of milk proteins resulting in the release of free amino acids and short peptides that influence the taste and ...

  16. Iron effect on the fermentative metabolism of Clostridium acetobutylicum ATCC 824 using cheese whey as substrate

    Directory of Open Access Journals (Sweden)

    Victoria Rosalía Durán-Padilla

    2014-12-01

    Full Text Available Butanol is considered a superior liquid fuel that can replace gasoline in internal combustion engines. It is produced by acetone-butanol-ethanol (ABE fermentation using various species of solventogenic clostridia. Performance of ABE fermentation process is severely limited mostly by high cost of substrate, substrate inhibition and low solvent tolerance; leading to low product concentrations, low productivity, low yield, and difficulty in controlling culture metabolism. In order to decrease the cost per substrate and exploit a waste generated by dairy industry, this study proposes using cheese whey as substrate for ABE fermentation. It was observed that the addition of an iron source was strictly necessary for the cheese whey to be a viable substrate because this metal is needed to produce ferredoxin, a key protein in the fermentative metabolism of Clostridium acetobutylicum serving as a temporary electron acceptor. Lack of iron in the cheese whey impedes ferredoxin synthesis and therefore, restricts pyruvate-ferredoxin oxidoreductase activity leading to the production of lactic acid instead of acetone, butanol and ethanol. Moreover, the addition of FeSO4 notably improved ABE production performance by increasing butanol content (7.13 ± 1.53 g/L by 65% compared to that of FeCl3 (4.32 ± 0.94 g/L under the same fermentation conditions.

  17. Microbial background flora in small-scale cheese production facilities does not inhibit growth and surface attachment of Listeria monocytogenes.

    Science.gov (United States)

    Schirmer, B C T; Heir, E; Møretrø, T; Skaar, I; Langsrud, S

    2013-10-01

    The background microbiota of 5 Norwegian small-scale cheese production sites was examined and the effect of the isolated strains on the growth and survival of Listeria monocytogenes was investigated. Samples were taken from the air, food contact surfaces (storage surfaces, cheese molds, and brine) and noncontact surfaces (floor, drains, and doors) and all isolates were identified by sequencing and morphology (mold). A total of 1,314 isolates were identified and found to belong to 55 bacterial genera, 1 species of yeast, and 6 species of mold. Lactococcus spp. (all of which were Lactococcus lactis), Staphylococcus spp., Microbacterium spp., and Psychrobacter sp. were isolated from all 5 sites and Rhodococcus spp. and Chryseobacterium spp. from 4 sites. Thirty-two genera were only found in 1 out of 5 facilities each. Great variations were observed in the microbial background flora both between the 5 producers, and also within the various production sites. The greatest diversity of bacteria was found in drains and on rubber seals of doors. The flora on cheese storage shelves and in salt brines was less varied. A total of 62 bacterial isolates and 1 yeast isolate were tested for antilisterial activity in an overlay assay and a spot-on-lawn assay, but none showed significant inhibitory effects. Listeria monocytogenes was also co-cultured on ceramic tiles with bacteria dominating in the cheese production plants: Lactococcus lactis, Pseudomonas putida, Staphylococcus equorum, Rhodococcus spp., or Psychrobacter spp. None of the tested isolates altered the survival of L. monocytogenes on ceramic tiles. The conclusion of the study was that no common background flora exists in cheese production environments. None of the tested isolates inhibited the growth of L. monocytogenes. Hence, this study does not support the hypothesis that the natural background flora in cheese production environments inhibits the growth or survival of L. monocytogenes. Copyright © 2013 American

  18. Prevalence, molecular characterization of Staphylococcus aureus isolated from cheese and in vitro antibacterial activity of silver nanoparticles against such strains

    Directory of Open Access Journals (Sweden)

    Karima G. Abdel Hameed

    2015-07-01

    Full Text Available Aim: The aim was to investigate cheese samples for the prevalence of Staphylococcus aureus, evaluate multiplex polymerase chain reaction (PCR methods for S. aureus identification, as well as to determine the antibacterial activity of silver nanoparticles against such strains. Materials and Methods: Total of 100 random locally manufactured cheese samples were collected from Qena dairy markets, Egypt, and examined conventionally for the prevalence of S. aureus then, confirmation of these isolates were done using multiplex PCR. The antibacterial activity of silver nanoparticles against such isolates was also checked. Results: Lower prevalence of S. aureus in Damietta cheese (54% than in Kareish cheese (62% was recorded. As well lower frequency distribution for both S. aureus (36% and CNS (8% was also reported for Damietta cheese. Using of multiplex PCR method for S. aureus identification have been confirmed all 58 S. aureus stains that were identified conventionally by detection of two PCR products on agarose gel: The 791 bp and the 638 bp. The correlation coefficient between conventional and multiplex PCR method was 0.91 and was significant at p≤0.001. Regarding antibacterial activity of silver nanoparticles using disk diffusion method on Baird Parker agar it was found that inhibition zone of silver nanoparticles against S. aureus, was 19.2±0.91 mm and it was higher than that produced by gentamicin (400 units/ml 15.2±0.89 mm. Conclusions: The present study illustrated the higher prevalence of S. aureus in cheese samples that may constitute a public health hazard to consumers. According to the results, it can be concluded that silver nanoparticles can be used as an effective antibacterial against S. aureus. Thereby, there is a need for an appropriate study for using silver nanoparticles in cleaning and disinfection of equipment and in food packaging.

  19. Effects produced by different types of laser in cornea of Guinea pigs: Identification of a laser capable of producing superficial lesions without leaving scars.

    Science.gov (United States)

    Suárez, A C; Suárez, M F; Crim, N; Monti, R; Urrets-Zavalía, J A; Serra, H M

    2015-10-01

    Climatic droplets keratopathy (CDK) is closely associated with superficial corneal erosions and lack of protective mechanisms against the harmful effects of ultraviolet radiation (UVR) during a prolonged period of time. One of the difficulties in studying the pathogenic mechanisms involved in this human disease is the lack of an experimental animal model. In this paper, a study is conducted on the effects of 4 types of lasers at various powers and time conditions on the normal guinea pig corneas in order to select only one laser condition that reversibly injures the epithelium and superficial stroma, without leaving scarring. Damage was induced in the cornea of Guinea pigs using different powers and exposure times of 4 types of laser: argon, CO2, diode and Nd-Yag, and any injuries were evaluated by biomicroscopy (BM) and optical microscopy. Corneas from other normal animals were exposed to argon laser (350 mW, 0.3s, 50 μm of diameter), and the induced alterations were studied at different times using BM, optical coherence tomography (OCT) and transmission electron microscopy (TEM). Only argon laser at 350 mW, 0.3s, 50 μm of diameter produced epithelium and superficial stroma lesions. Some leukomas were observed by BM, and they disappeared by day 15. Corneal thickness measured by OCT decreased in the eyes treated with argon laser during the first week. Using TEM, different ultra structural alterations in corneal epithelium and stroma were observed during the early days, which disappeared by day 15. It was possible to develop reproducible corneal epithelium and anterior stroma injuries using Argon laser at 350 mW, 0.3s, 50 μm of diameter. In vivo and in vitro studies showed that injured corneas with these laser conditions did not leave irreversible microscopic or ultra structural alterations. This protocol of corneal erosion combined with exposure to UVR and partial deficiency of ascorbate in the diets of the animals for an extended period of time has been used in

  20. Staphylococcus aureus entrance into the dairy chain: Tracking S. aureus from dairy cow to cheese

    Directory of Open Access Journals (Sweden)

    Judith Kümmel

    2016-10-01

    Full Text Available Staphylococcus aureus is one of the most important contagious mastitis pathogens in dairy cattle. Due to its zoonotic potential, control of S. aureus is not only of great economic importance in the dairy industry but also a significant public health concern. The aim of this study was to decipher the potential of bovine udder associated S. aureus as reservoir for S. aureus contamination in dairy production and processing. From 18 farms, delivering their milk to an alpine dairy plant for the production of smeared semi-hard and hard cheese. 1176 quarter milk (QM samples of all cows in lactation (n = 294 and representative samples form bulk tank milk (BTM of all farms were surveyed for coagulase positive (CPS and coagulase negative Staphylococci (CNS. Furthermore, samples from different steps of the cheese manufacturing process were tested for CPS and CNS. As revealed by chemometric-assisted FTIR spectroscopy and molecular subtyping (spa typing and multi locus sequence typing, dairy cattle represent indeed an important, yet underreported, entrance point of S. aureus into the dairy chain. Our data clearly show that certain S. aureus subtypes are present in primary production as well as in the cheese processing at the dairy plant. However, although a considerable diversity of S. aureus subtypes was observed in QM and BTM at the farms, only certain S. aureus subtypes were able to enter and persist in the cheese manufacturing at the dairy plant and could be isolated from cheese until day fourteen of ripening. Farm strains belonging to the FTIR cluster B1 and B3, which show genetic characteristics (t2953, ST8, enterotoxin profile: sea/sed/sej of the recently described S. aureus genotype B, most successfully contaminated the cheese production at the dairy plant. Thus our study fosters the hypothesis that genotype B S. aureus represent a specific challenge in control of S. aureus in the dairy chain that requires effective clearance strategies and hygienic

  1. Effect of Allium sativum and fish collagen on the proteolytic and angiotensin-I converting enzyme-inhibitory activities in cheese and yogurt.

    Science.gov (United States)

    Shori, A B; Baba, A S; Keow, J N

    2012-12-15

    There is an increasing demand of functional foods in developed countries. Yogurt plays an important role in the management of blood pressure. Several bioactive peptides isolated from Allium sativum or fish collagen have shown antihypertensive activity. Thus, in the present study the effects of A. sativum and/or Fish Collagen (FC) on proteolysis and ACE inhibitory activity in yogurt (0, 7 and 14 day) and cheese (0, 14 and 28 day) were investigated. Proteolytic activities were the highest on day 7 of refrigerated storage in A. sativum-FC-yogurt (337.0 +/- 5.3 microg g(-1)) followed by FC-yogurt (275.3 +/- 2.0 microg g(-1)), A. sativum-yogurt (245.8 +/- 4.2 microg g(-1)) and plain-yogurt (40.4 +/- 1.2 microg g(-1)). On the other hand, proteolytic activities in cheese ripening were the highest (p sativum-cheeses (411.4 +/- 4.3 and 528.7 +/- 1.6 microg g(-1), respectively). However, the presence of FC increased the