Rapid detection of Lactobacillus kefiranofaciens in kefir grain and kefir milk using newly developed real-time PCR.

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Kim, Dong-Hyeon; Chon, Jung-Whan; Kim, Hong-Seok; Yim, Jin-Hyeok; Kim, Hyunsook; Seo, Kun-Ho

2015-04-01

Lactobacillus kefiranofaciens is an indicator microorganism for kefir and a key factor in kefir grain formation and kefiran production. We designed a novel real-time PCR primer and probe set, LKF_KU504, for the rapid detection of L. kefiranofaciens. In inclusivity and exclusivity tests, only 14 L. kefiranofaciens strains were positive among 61 microorganisms, indicating 100 % sensitivity and specificity. The LKF_KU504 set also differentiated kefir milk from 30 commercial nonkefir yogurts. The levels of L. kefiranofaciens in kefir grain and kefir milk were significantly different, indicating L. kefiranofaciens was more concentrated in kefir grain than in kefir milk.

The water kefir grain inoculum determines the characteristics of the resulting water kefir fermentation process.

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Laureys, D; De Vuyst, L

2017-03-01

To investigate the influence of the water kefir grain inoculum on the characteristics of the water kefir fermentation process. Three water kefir fermentation processes were started with different water kefir grain inocula and followed as a function of time regarding microbial species diversity, community dynamics, substrate consumption profile and metabolite production course. The inoculum determined the water kefir grain growth, the viable counts on the grains, the time until total carbohydrate exhaustion, the final metabolite concentrations and the microbial species diversity. There were always 2-10 lactic acid bacterial cells for every yeast cell and the majority of these micro-organisms was always present on the grains. Lactobacillus paracasei, Lactobacillus hilgardii, Lactobacillus nagelii and Saccharomyces cerevisiae were always present and may be the key micro-organisms during water kefir fermentation. Low water kefir grain growth was associated with small grains with high viable counts of micro-organisms, fast fermentation and low pH values, and was not caused by the absence of exopolysaccharide-producing lactic acid bacteria. The water kefir grain inoculum influences the microbial species diversity and characteristics of the fermentation process. A select group of key micro-organisms was always present during fermentation. This study allows a rational selection of a water kefir grain inoculum. © 2016 The Society for Applied Microbiology.

The evaluation of kefir pure culture starter: Liquid-core capsule entrapping microorganisms isolated from kefir grains.

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Wang, Liang; Zhong, Hao; Liu, Keying; Guo, Aizhen; Qi, Xianghui; Cai, Meihong

2016-10-01

The main purpose of this study was to develop a pure culture starter for producing kefir. In order to accomplish starter recycling, yeasts (Kluyveromyces marxianus strain, Pichia kudriavzevii clone), lactic acid bacteria (Lactobacillus kefiri strain F4Aa, Lactobacillus kefiri strain NM131-7, Lactobacillus kefiri strain NM132-3, Lactobacillus kefiri strain NM180-3, respectively), and acetic acid bacteria (Acetobacter lovaniensis strain) were entrapped in liquid core capsules based on the distribution ratio in kefir grains. The microbiological, antimicrobial, and chemical properties of kefir made with capsules (M) and kefir grains (K) were measured and compared. According to the results of plate counts in different selective medium, the number of yeasts and bacteria in the liquid core capsules gradually increased and stabilized after eight fermentation cycles. The results of gas chromatography-mass spectrometry showed that almost all the aroma components existed in the two type of kefir, except the ethyl lactate. There was no significant difference in alcohol content, protein content, and fat content, except the acidity and sugar content. Water holding capacity of kefir K was higher than kefir M. There were 14 same free amino acids in kefir M and kefir K, and the content of most free amino acids was similar. In antimicrobial test, there was no significant difference in both kefirs. © The Author(s) 2016.

Microbiological and chemical properties of kefir manufactured by entrapped microorganisms isolated from kefir grains.

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Chen, T-H; Wang, S-Y; Chen, K-N; Liu, J-R; Chen, M-J

2009-07-01

In this study, various yeasts (Kluyveromyces marxianus, Saccharomyces turicensis, Pichia fermentans) and lactic acid bacteria (Lactobacillus kefiranofaciens, Lactobacillus kefiri, Leuconostoc mesenteroides) were entrapped in 2 different microspheres using an entrapment ratio for the strains that was based on the distribution ratio of these organisms in kefir grains. The purpose of this study was to develop a new technique to produce kefir using immobilized starter cultures isolated from kefir grains. An increase in cell counts with fermentation cycles was observed for both the lactic acid bacteria (LAB) and yeasts, whereas the cell counts of kefir grains were very stable during cultivation. Scanning electron microscopy showed that the short-chain lactobacilli and lactococci occupied the surface of the LAB microspheres, whereas the long-chain lactobacilli were inside the microspheres. When the yeasts were analyzed, cells at a high density were entrapped in cracks on the surface and within the microspheres, where they were surrounded by the short-chain lactobacilli. The distribution of the LAB and yeast species in kefir produced from grains and microspheres showed that there was no significant difference between the kefirs produced by the 2 methods; moreover, Leu. mesenteroides and K. marxianus were the predominating microflora in both types of kefir. There was no significant difference in the ethanol and exopolysaccharide contents between the 2 kefirs, although the acidity was different.

"Petit suisse" cheese from kefir: an alternative dessert with microorganisms of probiotic activity

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Thanise Sabrina Souza Santos

2012-09-01

Full Text Available "Petit Suisse" is a creamy cheese. Kefir is a symbiotic mixture of lactic acid bacteria and yeasts with probiotic activity including immunomodulation and balance of intestinal microflora. The present study aims to develop "Petit Suisse" cheese from kefir. Kefir grains were grown in pasteurized cow milk, and after the separation of kefir the serum was discarded and the "Petit Suisse" cheese was prepared using strawberry, mangaba, herbs, and dried tomatoes. The acceptance of the different preparations was evaluated using a nine-point hedonic scale followed by ANOVA. The sweet and salty products were compared by the Student's t-test. Purchase intent was evaluated by the means test and frequency distribution. All products were well accepted by the judges. The product was characterized by low yield, but it can be prepared at home at low cost. The nutritional composition analyses and the variety of flavors as well as the range of age of the judges are alternatives for further studies.

Microbiota of kefir grains

OpenAIRE

Tomislav Pogačić; Sanja Šinko; Šimun Zamberlin; Dubravka Samaržija

2013-01-01

Kefir grains represent the unique microbial community consisting of bacteria, yeasts, and sometimes filamentous moulds creating complex symbiotic community. The complexity of their physical and microbial structures is the reason that the kefir grains are still not unequivocally elucidated. Microbiota of kefir grains has been studied by many microbiological and molecular approaches. The development of metagenomics, based on the identification without cultivation, is opening new possibilities f...

Kefir ve Kefir Kullanılarak Yapılan Bazı Ürünler

OpenAIRE

ESMEK, Emel; GÜZELER, Nuray

2018-01-01

Kefir, bakteri ve mayaların etkileriyle kefir daneleri içinde simbiyotik birleşmesi ile oluşan fermente bir süt ürünüdür. Kefir, ağızda hissedilen köpürücü etkisi, tipik maya tadı ve kendisine has belirli aromaları ile bilinir. Kefir fermentasyonun ana ürünleri içeceğin vizkozitesini, asitliğini ve düşük alkol içeriğini gösteren laktik asit, etanol ve karbondioksittir. İkincil bileşenler ise aroma kompozisyonuna katkıda bulunan, diasetil, asetaldehit, etil alkol ve aminoasittir. Kefir, vücudu...

Microbes of fermented kefir-like using combination of kefir grains and Bifidobacterium longum

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Sri Usmiati

2005-03-01

Full Text Available The objectives of research were to find out physico-chemical characters and to detect flavor volatile compound of kefir-like. Material used was skim milk TS 9.5% which was heated at 85oC for 30 minutes and cooled at 22oC before innoculation of the starter. Microorganisms used were (a Lactobacillus acidophilus P155110, (b Lactobacillus delbrueckii subsp. Bulgaricus NCIMB 11778, (c Lactococcus lactis P155610, (d Leuconostoc mesenteroides subsp. dextranicum NCIMB 3350, (e Acetobacter aceti P154810, (f Bifidobacterium longum BF1, and (g Saccharomyces cerevisiae P156252. The treatments consist of P1 = without (b; P2 = without (a; and P3= used (a until (g. The physico-chemical characters identified were lactic acid and lactose percentages, pH, viscosity, organoleptic test for intensity of kefir-like sensory attributes. Results indicated that B. longum was potential bacterium use for starter combination on kefir-like making. The use starter P1 combination has high acidity and viscosity, low pH and lactose percentage, and high intensity on attribute creamy-white color, soft and curdle consistency, and kefir specific aroma on kefir-like. Volatile compound acid group were dominate by high acidity character on kefir-like resulted from starter P1 combination. Compound of 3-hydroxi-2-butanone (acetoin was affecting butter-like of P3 character. This compound resulted from which is a character of fermented milk flavor was not detected on P1 kefir-like.

Kefir and health: a contemporary perspective.

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Ahmed, Zaheer; Wang, Yanping; Ahmad, Asif; Khan, Salman Tariq; Nisa, Mehrun; Ahmad, Hajra; Afreen, Asma

2013-01-01

Kefir and its related products are renowned nutraceutical dairy products produced through fermentation of yeasts and bacteria naturally present in grains of kefir. The nutritional attributes of this self-carbonated beverage are due to presence of vital nutrients such as carbohydrates, proteins, minerals, vitamins, and some nutraceutical components. Antimicrobial activity, better gut health, anticarcinogenic activity, control on serum glucose and cholesterol, control on lactose intolerance and better immune system can be achieved through its regular consumption. Moreover, on the one side kefir is good dietetic beverage, and of particular interest of athletes, and on the other side the whole kefir is good for feeding small babies and pre-schoolers for good tolerance against disease and quick weight gain. Lots of works have been done on kefir from a health point of view. This study summarizes all the data that have been compiled to date. The purpose of this review is to gather information about microbiological, chemical, nutritional, and therapeutic aspects of kefir and kefir-like products to provide justification for its consumption. This review leads us to conclude that kefir begins a new dawn of food for the mankind.

Investigation of the instability and low water kefir grain growth during an industrial water kefir fermentation process.

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Laureys, David; Van Jean, Amandine; Dumont, Jean; De Vuyst, Luc

2017-04-01

A poorly performing industrial water kefir production process consisting of a first fermentation process, a rest period at low temperature, and a second fermentation process was characterized to elucidate the causes of its low water kefir grain growth and instability. The frozen-stored water kefir grain inoculum was thawed and reactivated during three consecutive prefermentations before the water kefir production process was started. Freezing and thawing damaged the water kefir grains irreversibly, as their structure did not restore during the prefermentations nor the production process. The viable counts of the lactic acid bacteria and yeasts on the water kefir grains and in the liquors were as expected, whereas those of the acetic acid bacteria were high, due to the aerobic fermentation conditions. Nevertheless, the fermentations progressed slowly, which was caused by excessive substrate concentrations resulting in a high osmotic stress. Lactobacillus nagelii, Lactobacillus paracasei, Lactobacillus hilgardii, Leuconostoc mesenteroides, Bifidobacterium aquikefiri, Gluconobacter roseus/oxydans, Gluconobacter cerinus, Saccharomyces cerevisiae, and Zygotorulaspora florentina were the most prevalent microorganisms. Lb. hilgardii, the microorganism thought to be responsible for water kefir grain growth, was not found culture-dependently, which could explain the low water kefir grain growth of this industrial process.

Manufacture and characterization of kefir made from cow and buffalo milk, using kefir grain and starter culture.

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Gul, O; Mortas, M; Atalar, I; Dervisoglu, M; Kahyaoglu, T

2015-03-01

The microbiological and chemical characteristics as well as organic and amino acid profiles of kefir samples made from cow and buffalo milks fermented by kefir grains and starter culture were investigated during storage for 21 d at 4°C. After incubation, lactic, acetic, and citric acid concentrations showed a difference among the samples due to milk type and production methods. Storage time had little effect on the organic acid values of kefir samples. As compared with cow milk kefir, buffalo milk kefir had higher numbers of microorganisms, except lactobacilli, at the end of storage. Whereas pH and titratable acidity exhibited similar changes during storage in all kefir samples, ethanol levels were significantly increased in buffalo milk kefir samples. Glutamic acid was the major amino acid at all sampling times for all samples. Tyrosine, serine, histidine, alanine, methionine, and lysine concentrations were determined to be different in all samples depending on milk type. In general, due to the higher microbial population (especially yeast), kefir made from buffalo milk may be preferred. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Structural characterization of the exopolysaccharides from water kefir.

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Fels, Lea; Jakob, Frank; Vogel, Rudi F; Wefers, Daniel

2018-06-01

Water kefir is a beverage which is produced by initiating fermentation of a fruit extract/sucrose solution with insoluble kefir grains. Exopolysaccharides that are formed from sucrose play a major role in the kefir grain formation, but the exopolysaccharides in the kefir beverage and the detailed structural composition of the whole kefir grains have not been studied yet. Therefore, kefir grains and the corresponding kefir beverage were analyzed for exopolysaccharides by multiple chromatographic approaches and two-dimensional NMR spectroscopy. Furthermore, different fractionation techniques were applied to obtain further information about the exopolysaccharides. The exopolysaccharide-fraction of the investigated kefir beverage was predominantly composed of O3- and O2-branched dextrans as well as lower amounts of levans. The insoluble dextrans from the kefir grains were mostly O3-branched and contained an elevated portion of 1,3-linked glucose units compared to the soluble dextrans. The structurally different exopolysaccharides in water kefir suggest the involvement of multiple bacteria. Copyright © 2018 Elsevier Ltd. All rights reserved.

Kefir: a powerful probiotics with anticancer properties.

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Sharifi, Mohammadreza; Moridnia, Abbas; Mortazavi, Deniz; Salehi, Mahsa; Bagheri, Marzieh; Sheikhi, Abdolkarim

2017-09-27

Probiotics and fermented milk products have attracted the attention of scientists from various fields, such as health care, industry and pharmacy. In recent years, reports have shown that dietary probiotics such as kefir have a great potential for cancer prevention and treatment. Kefir is fermented milk with Caucasian and Tibet origin, made from the incubation of kefir grains with raw milk or water. Kefir grains are a mixture of yeast and bacteria, living in a symbiotic association. Antibacterial, antifungal, anti-allergic and anti-inflammatory effects are some of the health beneficial properties of kefir grains. Furthermore, it is suggested that some of the bioactive compounds of kefir such as polysaccharides and peptides have great potential for inhibition of proliferation and induction of apoptosis in tumor cells. Many studies revealed that kefir acts on different cancers such as colorectal cancer, malignant T lymphocytes, breast cancer and lung carcinoma. In this review, we have focused on anticancer properties of kefir.

Milk kefir: ultrastructure, antimicrobial activity and efficacy on aflatoxin B1 production by Aspergillus flavus.

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Ismaiel, Ahmed A; Ghaly, Mohamed F; El-Naggar, Ayman K

2011-05-01

The association of kefir microbiota was observed by electron microscopic examination. Scanning electron microscopic (SEM) observations revealed that kefir grain surface is very rough and the inner portions had scattered irregular holes on its surface. The interior of the grain comprised fibrillar materials which were interpreted as protein, lipid and a soluble polysaccharide, the kefiran complex that surrounds yeast and bacteria in the grain. Yeast was observed more clearly than bacteria on the outer portion of the grain. Transmission electron microscopic (TEM) observations of kefir revealed that the grain comprised a mixed culture of yeast and bacteria growing in close association with each other. Microbiota is dominated by budded and long-flattened yeast cells growing together with lactobacilli and lactococci bacteria. Bacterial cells with rounded ends were also observed in this mixed culture. Kefir grains, kefir suspensions, and kefiran were tested for antimicrobial activities against several bacterial and fungal species. The highest activity was obtained against Streptococcus faecalis KR6 and Fusarium graminearum CZ1. Growth of Aspergillus flavus AH3 producing for aflatoxin B1 for 10 days in broth medium supplemented with varying concentrations of kefir filtrate (%, v/v) showed that sporulation was completely inhibited at the higher concentrations of kefir filtrate (7-10%, v/v). The average values of both mycelial dry weights and aflatoxin B1 were completely inhibited at 10% (v/v). This is the first in vitro study about the antifungal characteristics of kefir against filamentous fungi which was manifested by applying its inhibitory effect on the productivity of aflatoxin B1 by A. flavus AH3.

Milk kefir: nutritional, microbiological and health benefits.

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Rosa, Damiana D; Dias, Manoela M S; Grześkowiak, Łukasz M; Reis, Sandra A; Conceição, Lisiane L; Peluzio, Maria do Carmo G

2017-06-01

Kefir is fermented milk produced from grains that comprise a specific and complex mixture of bacteria and yeasts that live in a symbiotic association. The nutritional composition of kefir varies according to the milk composition, the microbiological composition of the grains used, the time/temperature of fermentation and storage conditions. Kefir originates from the Caucasus and Tibet. Recently, kefir has raised interest in the scientific community due to its numerous beneficial effects on health. Currently, several scientific studies have supported the health benefits of kefir, as reported historically as a probiotic drink with great potential in health promotion, as well as being a safe and inexpensive food, easily produced at home. Regular consumption of kefir has been associated with improved digestion and tolerance to lactose, antibacterial effect, hypocholesterolaemic effect, control of plasma glucose, anti-hypertensive effect, anti-inflammatory effect, antioxidant activity, anti-carcinogenic activity, anti-allergenic activity and healing effects. A large proportion of the studies that support these findings were conducted in vitro or in animal models. However, there is a need for systematic clinical trials to better understand the effects of regular use of kefir as part of a diet, and for their effect on preventing diseases. Thus, the present review focuses on the nutritional and microbiological composition of kefir and presents relevant findings associated with the beneficial effects of kefir on human and animal health.

Properties and benefits of kefir -A review

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Stephen Moses John

2015-06-01

Full Text Available Kefir is becoming increasingly popular as a result of new research into its health benefits. It is a fermented milk drink which has its origin in the Caucasus Mountains of Russia. Kefir is prepared by inoculating milk with kefir grains which are a combination of bacteria and yeasts in a symbiotic matrix. The common microorganisms present are non-pathogenic bacteria, especially Lactobacillus sp. and yeasts. Kefir has a long history of health benefits in Eastern European countries. It is believed that kefir has therapeutic effects, thus it is important to study the various properties contained in, and exhibited by it. This review includes a critical revision of the antimicrobial, anti-carcinogenic, probiotic and prebiotic properties of kefir. Other health benefits, like reducing cholesterol and improving lactose tolerance are also discussed.

Determination of lactic microflora of kefir grains and kefir beverage by using culture-dependent and culture-independent methods.

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Kesmen, Zülal; Kacmaz, Nazife

2011-01-01

In this study, we investigated the bacterial compositions of kefir grains and kefir beverages collected from different regions of Turkey by using culture-independent and culture-dependent methods. In the culture-independent detection, 10 different species of bacteria were detected in total by using the polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analysis of the 16S rRNA gene V3 region. Among these species, Lactobacillus kefiranofaciens was the most dominant one in the kefir grains, while Lactococcus lactis was found to be significantly prevalent in the kefir beverages. In the culture-dependent detection, the primary differentiation and grouping of the isolates from kefir beverages and kefir grains were performed using repetitive sequence-based PCR (rep-PCR) fingerprinting, and the results were validated by 16S rDNA full-length sequencing. According to the results of culture-dependent methods, the most frequently isolated species were L. lactis, Leuconostoc mesenteroides, and Lactobacillus kefiri, respectively. Only 3 species, which are L. lactis, Lactobacillus acidophilus, and Streptococcus thermophilus, were detected with both culture-dependent and culture-independent methods. This study showed that the combination of both methods is necessary for a detailed and reliable investigation of microbial communities in kefir grains and kefir beverages. Due to their artisan- and region-dependent microflora, kefir products can be a source of interesting lactic acid bacteria, either new taxa or strains with specific functional properties, which might be used for the development of new starter cultures and innovative food products. Therefore, an increasing demand exists for new strains that show desirable effects on the product characteristics Artisan dairy products are a candidate source of such microorganisms. For this reason, in this study, the bacterial compositions of kefir grains and kefir beverages obtained from

Peptide profiling of bovine kefir reveals 236 unique peptides released from caseins during its production by starter culture or kefir grains.

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Ebner, Jennifer; Aşçı Arslan, Ayşe; Fedorova, Maria; Hoffmann, Ralf; Küçükçetin, Ahmet; Pischetsrieder, Monika

2015-03-18

Kefir has a long tradition in human nutrition due to its presupposed health promoting effects. To investigate the potential contribution of bioactive peptides to the physiological effects of kefir, comprehensive analysis of the peptide profile was performed by nano-ESI-LTQ-Orbitrap MS coupled to nano-ultrahigh-performance liquid chromatography. Thus, 257 peptides were identified, mainly released from β-casein, followed by αS1-, κ-, and αS2-casein. Most (236) peptides were uniquely detected in kefir, but not in raw milk indicating that the fermentation step does not only increase the proteolytic activity 1.7- to 2.4-fold compared to unfermented milk, but also alters the composition of the peptide fraction. The influence of the microflora was determined by analyzing kefir produced from traditional kefir grains or commercial starter culture. Kefir from starter culture featured 230 peptide sequences and showed a significantly, 1.4-fold higher proteolytic activity than kefir from kefir grains with 127 peptides. A match of 97 peptides in both varieties indicates the presence of a typical kefir peptide profile that is not influenced by the individual composition of the microflora. Sixteen of the newly identified peptides were previously described as bioactive, including angiotensin-converting enzyme (ACE)-inhibitory, antimicrobial, immunomodulating, opioid, mineral binding, antioxidant, and antithrombotic effects. The present study describes a comprehensive peptide profile of kefir comprising 257 sequences. The peptide list was used to identify 16 bioactive peptides with ACE-inhibitory, antioxidant, antithrombotic, mineral binding, antimicrobial, immunomodulating and opioid activity in kefir. Furthermore, it was shown that a majority of the kefir peptides were not endogenously present in the raw material milk, but were released from milk caseins by proteases of the microbiota and are therefore specific for the product. Consequently, the proteolytic activity and the

POTENSI KEFIR SEBAGAI ANTIBAKTERI Propionibacterium acnes

OpenAIRE

., Michael

2015-01-01

Jerawat merupakan suatu keadaan dimana pori-pori kulit tersumbat oleh kotoran dan adanya bakteri Propionibacterium acnes yang berkembang biak di daerah sumbatan tersebut. Di Indonesia, masyarakat mulai melirik suatu produk minuman yang dipercaya secara empiris dapat mengatasi masalah jerawat, yaitu produk minuman fermentasi kefir. Kefir merupakan produk fermentasi yang memiliki cita rasa asam dan sedikit beralkohol. Kefir dapat difermentasi dengan air maupun dengan susu. Kan...

BIOTECHNOLOGY FOR KEFIR WITH NEW QUALITIES

Directory of Open Access Journals (Sweden)

A. N. Ponomarev

2014-01-01

Full Text Available Summary. Modern kefir production is based on the milk acidification process with the use of kefir grains by alcohol and lactic acid fermentation. Casein large molecules are fermented by sourdough’ microorganisms, and as a result they are digested much more effectively by the body. Thanks to a special composition of the sourdough’ microbiota, which composed of yeast, lactic acid and acetic acid bacteria, kefir is especially useful for a person of any age, helps to restore energy balance of human body, beneficial effects on the nervous system and metabolic processes. On the basis of the traditional technology of kefir production, which includes processes of normalization, homogenization, pasteurization, cooling to a temperature of fermentation, injection of sourdough, has been developed kefir production technology with the introduction of the ferment transglyutaminase that provides the generation of its own lactoferrin by the composition of microorganisms in kefir grains. Lactoferrin content ranges from 500 to 1100 mg/l, which is considerably higher than in the control group (300 mg/l. Lactoferrin is natural antioxidant that prevents the effect of early aging of the organism, contributes to the preservation of a healthy gastrointestinal tract. In many ways lactoferrin contributes to the preservation of health and fully supports the active longevity.

Kefir: a multifaceted fermented dairy product.

Science.gov (United States)

Nielsen, Barbara; Gürakan, G Candan; Unlü, Gülhan

2014-12-01

Kefir is a fermented dairy beverage produced by the actions of the microflora encased in the "kefir grain" on the carbohydrates in the milk. Containing many bacterial species already known for their probiotic properties, it has long been popular in Eastern Europe for its purported health benefits, where it is routinely administered to patients in hospitals and recommended for infants and the infirm. It is beginning to gain a foothold in the USA as a healthy probiotic beverage, mostly as an artisanal beverage, home fermented from shared grains, but also recently as a commercial product commanding shelf space in retail establishments. This is similar to the status of yogurts in the 1970s when yogurt was the new healthy product. Scientific studies into these reported benefits are being conducted into these health benefits, many with promising results, though not all of the studies have been conclusive. Our review provides an overview of kefir's structure, microbial profile, production, and probiotic properties. Our review also discusses alternative uses of kefir, kefir grains, and kefiran (the soluble polysaccharide produced by the organisms in kefir grains). Their utility in wound therapy, food additives, leavening agents, and other non-beverage uses is being studied with promising results.

Acquisition of the yeast Kluyveromyces marxianus from unpasteurised milk by a kefir grain enhances kefir quality.

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Gethins, Loughlin; Rea, Mary C; Stanton, Catherine; Ross, R Paul; Kilcawley, Kieran; O'Sullivan, Maurice; Crotty, Suzanne; Morrissey, John P

2016-08-01

Kefir is a fermented milk beverage consumed for nutritional and health tonic benefits in many parts of the world. It is produced by the fermentation of milk with a consortium of bacteria and yeast embedded within a polysaccharide matrix. This consortium is not well defined and can vary substantially between kefir grains. There are little data on the microbial stability of kefir grains, nor on interactions between microbes in the grain and in the milk. To study this, a grain was split, with one half of each stored at -20°C and the other half passaged repeatedly in whole unpasteurised milk. Grains passaged in the unpasteurised milk recovered vigour and acquired the yeast Kluyveromyces marxainus from the milk which was confirmed to be the same strain by molecular typing. Furthermore, these passaged grains produced kefir that was distinguished chemically and organoleptically from the stored grains. Some changes in ultrastructure were also observed by scanning electron microscopy. The study showed that kefir grains can acquire yeast from their environment and the final product can be influenced by these newly acquired yeasts. Kluyveromyces marxianus is considered to be responsible for some of the most important characteristics of kefir so the finding that this yeast is part of the less stable microbiota is significant. © FEMS 2016. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Formation of volatile compounds in kefir made of goat and sheep milk with high polyunsaturated fatty acid content.

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Cais-Sokolińska, D; Wójtowski, J; Pikul, J; Danków, R; Majcher, M; Teichert, J; Bagnicka, E

2015-10-01

This article explored the formation of volatile compounds during the production of kefir from goat and sheep milks with high polyunsaturated fatty acids (PUFA) as a result of feeding animals forage supplemented with maize dried distillers grains with solubles (DDGS). The increased PUFA content of the goat and sheep milks resulted in significant changes to the fermentation process. In particular, apart from an increase in the time taken to ferment sheep milk, fermentation yielded less 2,3-butanedione. The highest quantities of this compound were assayed in kefir produced from goat milk with an increased content of PUFA. An increase of PUFA significantly elevated ethanal synthesis during lactose-alcohol fermentation of sheep milk. Neither the origin of milk (sheep or goat) nor the level of PUFA had any statistical effect on the amount of ethanal assayed during the fermentation of milk and within the finished product. The proportion of l(+)-lactic acid was higher in kefirs produced using goat milk compared with sheep milk and did not depend on the content of PUFA in milk fat. The content of PUFA had a significant effect on the aroma profile of the resulting kefirs. An increase in PUFA content resulted in the loss of whey aroma in goat milk kefirs and the animal odor in sheep milk kefirs, and a creamy aroma became more prevalent in kefirs made from sheep milk. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effects of kefir on ischemia-reperfusion injury.

Science.gov (United States)

Yener, A U; Sehitoglu, M H; Ozkan, M T A; Bekler, A; Ekin, A; Cokkalender, O; Deniz, M; Sacar, M; Karaca, T; Ozcan, S; Kurt, T

2015-01-01

We aimed to investigate the effect of kefir on Ischemia-Reperfusion (I/R) injury on rats. 24 male Sprague-Dawley rats between 250-350 g were selected. Rats were divided into three groups, and there were eight rats in each group. Rats were fed for 60 days. All of the rats were fed with the same diet for the first 30 days. In the second thirty days, kefir [10 cc/kg/day body weight (2 x 109 cfu/kg/day)] was added to the diet of the study group by gavage method. In all groups, lung and kidney tissues were removed after the procedure and rats were sacrificed. The biochemical and histopathological changes were observed in the lung and kidney within the samples. Serum urea, creatinine and tumor necrosis factor (TNF-α) were determined. Kefir + I/R groups was compared with I/R groups, a significant decrease (p Kefir + I/R groups of renal tissues were significantly (p Kefir reduced the levels of serum urea, creatinine and TNF-α significantly.   This would be useful in this model against ischemia/reperfusion, and shows the protective effect of kefir in tissue and serum functions.

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

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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.

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

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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

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

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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.

Kefir treatment ameliorates dextran sulfate sodium-induced colitis in rats.

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Senol, Altug; Isler, Mehmet; Sutcu, Recep; Akin, Mete; Cakir, Ebru; Ceyhan, Betul M; Kockar, M Cem

2015-12-14

To investigate the preventive effect of kefir on colitis induced with dextran sulfate sodium (DSS) in rats. Twenty-four male Wistar-albino rats were randomized into four groups: normal control, kefir-control, colitis, and kefir-colitis groups. Rats in the normal and kefir-control groups were administered tap water as drinking water for 14 d. Rats in the colitis and kefir-colitis groups were administered a 3% DSS solution as drinking water for 8-14 d to induce colitis. Rats in the kefir-control and kefir-colitis groups were administered 5 mL kefir once a day for 14 d while rats in the normal control and colitis group were administered an identical volume of the placebo (skim milk) using an orogastric feeding tube. Clinical colitis was evaluated with reference to the disease activity index (DAI), based on daily weight loss, stool consistency, and presence of bleeding in feces. Rats were sacrificed on the 15(th) day, blood specimens were collected, and colon tissues were rapidly removed. Levels of myeloperoxidase (MPO), tumor necrosis factor (TNF)-α, interleukin (IL)-10, malondialdehyde, and inducible nitric oxide synthase (iNOS) were measured in colon tissue. The DAI was lower in the kefir-colitis group than in the colitis group (on the 3(rd) and 5(th) days of colitis induction; P < 0.01). The DAI was also significantly higher in the colitis group between days 2 and 6 of colitis induction when compared to the normal control and kefir-control groups. The DAI was statistically higher only on the 6(th) day in the kefir-colitis group when compared to that in the normal control groups. Increased colon weight and decreased colon length were observed in colitis-induced rats. Mean colon length in the colitis group was significantly shorter than that of the kefir-control group. Kefir treatment significantly decreased histologic colitis scores (P < 0.05). MPO activity in the colitis group was significantly higher than in the kefir-control group (P < 0.05). Kefir treatment

Production and quality of kefir cultured butter

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Yaşar Karaca

2018-01-01

Full Text Available Cream is the main raw material for the butter production and reflects its properties into butter quality. Maturation of cream with appropriate starter culture is important for butter quality, sensory properties and shelf life of the end product. Kefir grains contain important probiotics for healthy nutrition including lactic acid bacteria, acetic acid bacteria, and yeasts in high numbers. The aim of this research was to determine the properties of butter produced using natural kefir culture during a 21-day cold storage. Determination of microbial, chemical and sensory properties of butter samples was carried out. Control sample (KOTE had 6.64 log CFU g-1 Lactococcus spp. while kefir cultured butter samples had 8.58 log CFU g-1. Kefir cultured butter contained 5.24 log CFU g-1 L. acidophilus at Day 1, while control samples did not have L. acidophilus. Acetaldehyde content of kefir cultured butter was significantly higher from the uncultured butter. According to sensory evaluation performed by 12 panelists, KKTE samples had better sensory properties than those observed in the KOTE samples.

STUDY OF GUSTATORY AND STRUCTURAL PROPERTIES OF KEFIR PRODUCT

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MILENA H. MOMCHILOVA

2012-06-01

Full Text Available The subject of the study is the improvement of Kefir culture. For this investigation it was used Kefir culture and two series of experiments were carried out. Yeasts from probiotic strain Saccharomyces boulardii were added in the first series and the lactic acid bacteria (LAB of Streptococcus thermophilus strain, with a polysaccharide activity were added to Kefir culture in the second series. The fermentation conditions were 30°C, duration 16 hours and cooling 4 hours up to 4°C. The characteristics of Kefir were analyzed by determination of: pH, acidity, qualitative reaction for existence of diacetyl, cell number of LAB and yeasts. The structural properties of Kefir were evaluated by microscopic study.

Kefir induces apoptosis and inhibits cell proliferation in human acute erythroleukemia.

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Jalali, Fatemeh; Sharifi, Mohammadreza; Salehi, Rasoul

2016-01-01

Acute erythroleukemia is an uncommon subtype of acute myeloid leukemia which has been considered to be a subtype of AML with a worse prognosis. Intensive chemotherapy is the first line of treatment. In recent years, the effect of kefir on some malignancies has been experimented. Kefir is a kind of beverage, which obtained by incubation of kefir grains with raw milk. Kefir grains are a symbiotic complex of different kinds of yeasts and bacteria, especially lactic acid bacteria which gather in a mostly carbohydrate matrix, named kefiran. We investigated the effect of kefir on acute erythroleukemia cell line (KG-1) and peripheral blood mononuclear cells (PBMCs). The cell line and PBMCs were treated with different doses of kefir and milk and incubated for three different times. We used Polymixin B to block the lipopolysaccharide and NaOH (1 mol/l) to neutralize the acidic media. Viability was detected by MTT assay. Apoptosis and necrosis were assessed by annexin-propidium iodide staining. Our results showed that kefir induced apoptosis and necrosis in KG-1 cell line. It was revealed that kefir decreased proliferation in erythroleukemia cell line. We did not observe a remarkable effect of kefir on PBMCs. Our study suggested that kefir may have potential to be an effective treatment for erythroleukemia.

KAJIAN PENGGUNAAN EKSTRAK SUSU KEDELAI TERHADAP KUALITAS KEFIR SUSU KAMBING

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M. E Sawitri

2012-04-01

Full Text Available ABSTRAK Tujuan penelitian untuk mengkaji kualitas kefir susu kambing yang telah diberi perlakuan penggunaan ekstrak susu kedelai ditinjau dari nilai pH, viskositas, kadar protein,kadar lemak dan kadar isoflavon. Hasil penelitian diharapkan dapat memberikan informasi bagi praktisi dan industri tentang kualitas kefir susu kambing sebagai bahan pangan yang dapat menunjang kesehatan. Materi penelitian adalah kefir susu kambing  yang diberi perlakuan penambahan ekstrak susu kedelai sebesar 10% (K1,20%(K2 dan 30%(K3 dari volume kefir susu kambing. Metode penelitian menggunakan metode percobaan dengan Rancangan Acak Kelompok (RAK. Parameter yang dikaji adalah nilai pH, viskositas, kadar protein,kadar lemak dan kadar isoflavon kefir susu kambing. Hasil penelitian menunjukkan bahwa  penambahan ekstrak susu kedelai tidak memberikan perbedaan pengaruh yang nyata (P>0,05  terhadap nilai pH, memberikan perbedaan pengaruh yang sangat nyata (P0,05 on pH and that each treatments were given highly significant effect (P<0,01 on protein,fat and isoflavon content of goat milk kefir. The conclusion of this research was addition of soymilk extract had increase quality of goat milk kefir.   Keywords : goat milk kefir, soymilk extract

Administration of kefir-fermented milk protects mice against Giardia intestinalis infection.

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Franco, Mariana Correa; Golowczyc, Marina A; De Antoni, Graciela L; Pérez, Pablo F; Humen, Martín; Serradell, María de los Angeles

2013-12-01

Giardiasis, caused by the protozoan Giardia intestinalis, is one of the most common intestinal diseases worldwide and constitutes an important problem for the public health systems of various countries. Kefir is a probiotic drink obtained by fermenting milk with 'kefir grains', which consist mainly of bacteria and yeasts that coexist in a complex symbiotic association. In this work, we studied the ability of kefir to protect mice from G. intestinalis infection, and characterized the host immune response to this probiotic in the context of the intestinal infection. Six- to 8-week-old C75BL/6 mice were separated into four groups: controls, kefir mice (receiving 1 : 100 dilution of kefir in drinking water for 14 days), Giardia mice (infected orally with 4×10(7) trophozoites of G. intestinalis at day 7) and Giardia-kefir mice (kefir-treated G. intestinalis-infected mice), and killed at 2 or 7 days post-infection. Kefir administration was able to significantly reduce the intensity of Giardia infection at 7 days post-infection. An increase in the percentage of CD4(+) T cells at 2 days post-infection was observed in the Peyer's patches (PP) of mice belonging to the Giardia group compared with the control and kefir groups, while the percentage of CD4(+) T cells in PP in the Giardia-kefir group was similar to that of controls. At 2 days post-infection, a reduction in the percentage of B220-positive major histocompatibility complex class II medium cells in PP was observed in infected mice compared with the other groups. At 7 days post-infection, Giardia-infected mice showed a reduction in RcFcε-positive cells compared with the control group, suggesting a downregulation of the inflammatory response. However, the percentages of RcFcε-positive cells did not differ from controls in the kefir and Giardia-kefir groups. An increase in IgA-positive cells was observed in the lamina propria of the kefir group compared with controls at 2 days post-infection. Interestingly, the

Analysis of Proximate and Protein Profile of Kefir from Fermented Goat and Cow Milk

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Erwin Hidayat

2015-09-01

Full Text Available This research aims to analyze the characteristics of proximate and protein profile in kefir from fermented goat milk and cow milk with different concentration of kefir grains. The research design was true experimental with Completely Randomized Design (CRD of 3 repetitions. The research procedures consisted of kefir production, proximate analysis and protein profile characterization. Proximate assay result was analyzed by using LSD, whereas the protein profile was analyzed by descriptive qualitative method. Based on the analysis of kefir proximate levels, the kefir grain (5% showed the highest proximate level of both kefirs from goat milk and cow milk. The analysis of protein profile of cow milk kefir showed 75 kDa of protein ribbon, while the goat milk kefir showed 48 kDa, 60 kDa and 75 kDa. Therefore it can be concluded that the proximate level of goat and cow milk kefir with different concentration of kefir grains showed significant differences in the nutrition content as well as its protein profiles.Tujuan dari penelitian ini adalah menganalisis karakteristik proksimat dan profil protein pada kefir hasil fermentasi susu kambing dan susu sapi dengan konsentrasi biji kefir yang berbeda-beda. Penelitian ini adalah eksperimen murni, dengan Rancangan Acak Lengkap (RAL 3 kali ulangan. Prosedur penelitian meliputi pembuatan kefir, analisis proksimat dan profil protein. Data hasil proksimat dianalisi uji BNT, sedangkan profil protein dianalisis deskriptif kualitatif. Berdasarkan analisis kadar proksimat kefir, kefir grains 5% menunjukan kadar proksimat paling tinggi baik pada kefir susu kambing dan susu sapi. Sedangkan analisis profil protein kefir susu sapi menunjukan pita protein 75 kDa, pada kefir susu kambing yaitu 48 kDa, 60 kDa dan 75 kDa. Simpulan dari penelitian ini bahwa kadar proksimat kefir susu kambing dan susu sapi dengan konsentrasi kefir grains yang berbeda menunjukan perbedaan kandungan yang berbeda secara signifikan dengan

Effect of kefir on Fusobacterium nucleatum in potentially preventing intestinal cancer

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Zeynep Banu Guzel-Seydim

2016-07-01

Full Text Available Background: Fusobacterium spp. are known to be part of mouth and intestinal microbiota. Fusobacterium nucleatum is an obligate anaerobe, Gram negative, non-spore forming pleomorphic bacillus that can cause diseases not only in the mouth and teeth but also in the brain, pleura, lungs and liver. It was noted that F. nucleatum induces fetal death (fetal demise in pregnant women. Recent studies indicate that F. nucleatum could lead to colon cancer by binding to the epithelial tissue. Kefir is produced from kefir grains that are a source of probiotics. Fermented dairy products and especially kefir and yogurt are significant for functional nutrition. In kefir grains, lactic acid bacteria, acetic acid bacteria and yeasts are embedded in a polysaccharide matrix, called kefiran. When kefir grains are added to milk and incubated for approximately 22 h at 25°C, microorganisms in the grains continue to proliferate in milk with the production of functional metabolic compounds. While yogurt has mainly two bacteria, authentic kefir has its characteristic Lactobacillus kefiranofaciens, Lactobacillus kefir and Lactobacillus kefirgranum, in addition to many other types of lactic acid bacteria (LAB. Previous studies have indicated that fermented dairy products can cause probiotic effects such as improvement in digestive system health, reduction in serum cholesterol, improvement in lactose tolerance, improvement in immune function, control of irritable bowel symptoms, and anticarcinogenic properties. Objective: The aim of this research was to report the effects of fermented dairy products in vitro on the growth of F. nucleatum. Milk, kefir made from natural kefir grains, commercial kefir produced from kefir starter culture, yogurt produced from natural yogurt starter culture and commercial yogurt produced from yogurt starter culture were used against F. nucleatum. Methods: F. nucleatum (ATCC 25586 was grown in Fluid Thioglycollate Medium at 37°C for 3 days under

Kefir and Cancer: A Systematic Review of Literatures.

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Rafie, Nahid; Golpour Hamedani, Sahar; Ghiasvand, Reza; Miraghajani, Maryam

2015-12-01

Some studies have suggested chemopreventive effects of kefir, a fermented milk product, on carcinogenesis. The aim of this review study was to evaluate the scientific evidence for effects of kefir on cancer prevention and treatment. We systematically searched for all relevant studies published before June 2015, using PubMed, Google scholar, Cochrane and Science Direct, SID, MedLib and Srlst databases. Relevant studies were reviewed based on systematic review (PRISMA) guidelines. From a total of 2208 papers obtained at the initial database search, 11 publications including 7 in vitro and 4 experimental studies were eligible. In vitro studies on breast, colon, skin and gastric cancers and leukemia cell lines and experimental studies on different sarcomas consistently showed beneficial effects of kefir on cancer prevention and treatment. The results of this systematic review suggest that kefir may be associated with cancer prevention and it also has beneficial effects in cancer treatment. This protection may be associated with kefir bioactive components including peptides, polysaccharides and sphingolipids.

Microbiological, technological and therapeutic properties of kefir: a natural probiotic beverage

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Analy Machado de Oliveira Leite

2013-01-01

Full Text Available Kefir is a fermented milk beverage produced by the action of bacteria and yeasts that exist in symbiotic association in kefir grains. The artisanal production of the kefir is based on the tradition of the peoples of Caucasus, which has spread to other parts of the world, from the late 19th century, and nowadays integrates its nutritional and therapeutic indications to the everyday food choices of several populations. The large number of microorganisms present in kefir and their microbial interactions, the possible bioactive compounds resulting of microbial metabolism, and the benefits associated with the use this beverage confers kefir the status of a natural probiotic, designated as the 21th century yoghurt. Several studies have shown that kefir and its constituents have antimicrobial, antitumor, anticarcinogenic and immunomodulatory activity and also improve lactose digestion, among others. This review includes data on the technological aspects, the main beneficial effects on human health of kefir and its microbiological composition. Generally, kefir grains contain a relatively stable and specific microbiota enclosed in a matrix of polysaccharides and proteins. Microbial interactions in kefir are complex due to the composition of kefir grains, which seems to differ among different studies, although some predominant Lactobacillus species are always present. Besides, the specific populations of individual grains seem to contribute to the particular sensory characteristics present in fermented beverages. This review also includes new electron microscopy data on the distribution of microorganisms within different Brazilian kefir grains, which showed a relative change in its distribution according to grain origin.

Microbiological, technological and therapeutic properties of kefir: a natural probiotic beverage

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de Oliveira Leite, Analy Machado; Miguel, Marco Antonio Lemos; Peixoto, Raquel Silva; Rosado, Alexandre Soares; Silva, Joab Trajano; Paschoalin, Vania Margaret Flosi

2013-01-01

Kefir is a fermented milk beverage produced by the action of bacteria and yeasts that exist in symbiotic association in kefir grains. The artisanal production of the kefir is based on the tradition of the peoples of Caucasus, which has spread to other parts of the world, from the late 19th century, and nowadays integrates its nutritional and therapeutic indications to the everyday food choices of several populations. The large number of microorganisms present in kefir and their microbial interactions, the possible bioactive compounds resulting of microbial metabolism, and the benefits associated with the use this beverage confers kefir the status of a natural probiotic, designated as the 21th century yoghurt. Several studies have shown that kefir and its constituents have antimicrobial, antitumor, anticarcinogenic and immunomodulatory activity and also improve lactose digestion, among others. This review includes data on the technological aspects, the main beneficial effects on human health of kefir and its microbiological composition. Generally, kefir grains contain a relatively stable and specific microbiota enclosed in a matrix of polysaccharides and proteins. Microbial interactions in kefir are complex due to the composition of kefir grains, which seems to differ among different studies, although some predominant Lactobacillus species are always present. Besides, the specific populations of individual grains seem to contribute to the particular sensory characteristics present in fermented beverages. This review also includes new electron microscopy data on the distribution of microorganisms within different Brazilian kefir grains, which showed a relative change in its distribution according to grain origin. PMID:24294220

Microbiological, technological and therapeutic properties of kefir: a natural probiotic beverage.

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de Oliveira Leite, Analy Machado; Miguel, Marco Antonio Lemos; Peixoto, Raquel Silva; Rosado, Alexandre Soares; Silva, Joab Trajano; Paschoalin, Vania Margaret Flosi

2013-01-01

Kefir is a fermented milk beverage produced by the action of bacteria and yeasts that exist in symbiotic association in kefir grains. The artisanal production of the kefir is based on the tradition of the peoples of Caucasus, which has spread to other parts of the world, from the late 19(th) century, and nowadays integrates its nutritional and therapeutic indications to the everyday food choices of several populations. The large number of microorganisms present in kefir and their microbial interactions, the possible bioactive compounds resulting of microbial metabolism, and the benefits associated with the use this beverage confers kefir the status of a natural probiotic, designated as the 21(th) century yoghurt. Several studies have shown that kefir and its constituents have antimicrobial, antitumor, anticarcinogenic and immunomodulatory activity and also improve lactose digestion, among others. This review includes data on the technological aspects, the main beneficial effects on human health of kefir and its microbiological composition. Generally, kefir grains contain a relatively stable and specific microbiota enclosed in a matrix of polysaccharides and proteins. Microbial interactions in kefir are complex due to the composition of kefir grains, which seems to differ among different studies, although some predominant Lactobacillus species are always present. Besides, the specific populations of individual grains seem to contribute to the particular sensory characteristics present in fermented beverages. This review also includes new electron microscopy data on the distribution of microorganisms within different Brazilian kefir grains, which showed a relative change in its distribution according to grain origin.

Exploring the influence of culture conditions on kefir's anticancer properties.

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Hatmal, Ma'mon M; Nuirat, Abeer; Zihlif, Malek A; Taha, Mutasem O

2018-05-01

Cancer is a major health problem in many parts of the world. Conventional anticancer treatments are painful, expensive, and unsafe. Therefore, demand is increasing for cancer treatments preferentially in the form of functional foods or nutritional supplements. Kefir, a traditional fermented milk dairy product, has significant antimutagenic and antitumor properties. This research addresses the hypothesis that kefir's anticancer properties are affected by fermentation conditions. Initially, kefir extracts prepared under standard conditions were screened against 7 cancer cell lines using the tetrazolium dye 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric assay. Colon cancer and chronic myelogenous leukemia cells were found to be most susceptible to kefir extracts. Subsequently, a factorial design was implemented to assess the effects of 3 fermentation times (24, 48, and 72 h), 3 kefir-to-milk ratios (2, 5, and 10% wt/vol), and 3 fermentation temperatures (4, 25, and 40°C) on kefir's anticancer properties. Remarkably, exploration of the fermentation conditions allowed the anticancer properties of kefir to be enhanced by 5- to 8-fold against susceptible cell lines. Overall, these results demonstrate the possibility of optimizing the anticancer properties of kefir as a functional food in cancer therapy. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Milk kefir: composition, microbial cultures, biological activities, and related products.

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Prado, Maria R; Blandón, Lina Marcela; Vandenberghe, Luciana P S; Rodrigues, Cristine; Castro, Guillermo R; Thomaz-Soccol, Vanete; Soccol, Carlos R

2015-01-01

In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir's exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir's microflora and the importance of kefiran as a beneficial health substance.

Effects of different fermentation parameters on quality characteristics of kefir.

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Kök-Taş, Tuğba; Seydim, Atif C; Ozer, Barbaros; Guzel-Seydim, Zeynep B

2013-02-01

The main objective of the study was to determine the effects of different fermentation parameters on kefir quality. Kefir samples were produced using kefir grains or natural kefir starter culture, and fermentation was carried out under normal or modified atmosphere (10% CO(2)) conditions. The microbiological (lactobacilli, lactococci, Lactobacillus acidophilus, Bifidobacterium spp., and yeasts), chemical (pH, lactic acid, total solids, protein, ethanol, exopolysaccharide contents), rheological, and sensory properties of kefir samples were investigated during a 21-d storage period. The use of different fermentation parameters or the choice of grain versus natural kefir starter culture did not significantly affect the content of microorganisms. Lactobacilli, lactococci, and yeast contents of kefir samples varied between 9.21 and 9.28, 9.23 and 9.29, and 4.71 and 5.53 log cfu/mL, respectively, on d 1 of storage. Contents of L. acidophilus and Bifidobacterium spp. were between 5.78 and 6.43 and between 3.19 and 6.14 log cfu/mL, respectively, during 21 d of storage. During the storage period, pH, lactic acid (%), total solids (%), protein (%), acetaldehyde, and ethanol contents of kefir samples ranged from 4.29 to 4.53, from 0.81 to 0.95%, from 7.81 to 8.21%, from 3.09 to 3.48%, from 3.8 to 23.6 mg/L, and from 76.5 to 5,147 mg/L, respectively. The exopolysaccharide contents of the samples decreased during 21 d of cold storage; the samples fermented under modified atmosphere had relatively higher exopolysaccharide contents, indicating higher potential therapeutic properties. The kefir samples exhibited non-Newtonian pseudoplastic flow behavior according to the power law model. According to the sensory results, kefir produced from natural kefir starter culture under CO(2) atmosphere had the highest overall evaluation score at d 1. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Karakteristik Kimiawi dan Mikrobiologi Kefir Susu Sapi dengan Penambahan Susu Kedelai

OpenAIRE

Julianto, Budi; Rossi, Evy; ', Yusmarini

2016-01-01

The purpose of this research was to observe chemical and microbiology characteristic of three kind of kefir, made from cow milk with addition of soymilk. Observed kefirs were kefir whey (KW), kefir optima (KO), and kefir prima (KP). A Completely Randomized Design (CRD) was used in this research with six treatments and three replications treatment consists of KW1 (100% cow milk), KW2 (50% cow milk: soymilk 50%), KO1 (100% cow milk), KO2 (50% cow milk: 50% soymilk), KP1 (100% cow milk), and KP2...

Russian Kefir Grains Microbial Composition and Its Changes during Production Process.

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Kotova, I B; Cherdyntseva, T A; Netrusov, A I

2016-01-01

By combining DGGE-PCR method, classical microbiological analysis and light- and electron microscopic observations, it was found that the composition of microbial communities of central Russia regions kefir grains, starter and kefir drink include bacteria of the genera Lactobacillus, Leuconostoc and Lactococcus, and yeast anamorphs of the genera Saccharomyces, Kazachstania and Gibellulopsis. Fifteen prokaryotic and four eukaryotic pure cultures of microorganisms were isolated and identified from kefir grains. It has been shown that members of the genus Lactobacillus prevailed in kefir grains, whereas strains Leuconostoc pseudomesenteroides and Lactococcus lactis dominated in the final product - kefir drink. Yeasts contained in kefir grains in small amounts have reached a significant number of cells in the process of development of this dairy product. The possibility of reverse cell aggregation has been attempted in a mixed cultivation of all isolated pure cultures, but full formation kefir grains is not yet observed after 1.5 years of observation and reinoculations.

Kefir milk enhances intestinal immunity in young but not old rats.

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Thoreux, K; Schmucker, D L

2001-03-01

The adjuvant effect of kefir fermented milk on the mucosal and systemic immune systems was examined in young (6 mo old) and old (26 mo old) rats. Kefir-fed rats consisted of young or old rats consuming kefir-fermented milk ad libitum on a daily basis in addition to the standard diet, for 28 d. Control rats consumed only the standard diet. The rats were immunized intraduodenally with cholera toxin (CT) on d 7 and 21 and killed on d 28. The nonspecific serum immunoglobulin (Ig)A titers in kefir-fed and control rats did not differ in either age group. The serum anti-CT IgA antibody concentrations were significantly higher in the kefir-fed young rats compared with their age-matched controls (+86%, P: 120%, P: kefir-fed rats compared with their respective controls. Nevertheless, these results demonstrate that a kefir-supplemented diet affects the intestinal mucosal and systemic immune responses to intraduodenal CT differently in young and old rats. Most importantly, our data suggest that orally administered kefir enhances the specific intestinal mucosal immune response against CT in young adult, but not in senescent rats.

Antimicrobial Activity of Kefir against Various Food Pathogens and Spoilage Bacteria.

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Kim, Dong-Hyeon; Jeong, Dana; Kim, Hyunsook; Kang, Il-Byeong; Chon, Jung-Whan; Song, Kwang-Young; Seo, Kun-Ho

2016-01-01

Kefir is a unique fermented dairy product produced by a mixture of lactic acid bacteria, acetic acid bacteria, and yeast. Here, we compared the antimicrobial spectra of four types of kefirs (A, L, M, and S) fermented for 24, 36, 48, or 72 h against eight food-borne pathogens. Bacillus cereus , Staphylococcus aureus , Listeria monocytogenes , Enterococcus faecalis , Escherichia coli , Salmonella Enteritidis , Pseudomonas aeruginosa , and Cronobacter sakazakii were used as test strains, and antibacterial activity was investigated by the spot on lawn method. The spectra, potencies, and onsets of activity varied according to the type of kefir and the fermentation time. The broadest and strongest antimicrobial spectrum was obtained after at least 36-48 h of fermentation for all kefirs, although the traditional fermentation method of kefir is for 18-24 h at 25℃. For kefir A, B. cereus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited, while B. cereus , S. aureus , E. coli , S . Enteritidis, P. aeruginosa , and C. sakazakii were inhibited to different extents by kefirs L, M, and S. Remarkably, S. aureus , S . Enteritidis, and C. sakazakii were only inhibited by kefirs L, M, and S, and L. monocytogenes by kefir M after fermentation for specific times, suggesting that the antimicrobial activity is attributable not only to a low pH but also to antimicrobial substances secreted during the fermentation.

Comparison of antioxidant capacity of cow and ewe milk kefirs.

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Yilmaz-Ersan, Lutfiye; Ozcan, Tulay; Akpinar-Bayizit, Arzu; Sahin, Saliha

2018-05-01

This research aimed to evaluate the effects of using either grain or commercial starter culture on the antioxidative capacity of cow and ewe milk kefirs. The antioxidant capacity of kefir samples during fermentation and 21 d of storage was assessed by using 3 assays: 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical cation decolorization; 2,2-diphenyl-1-picrylhydrazyl (DPPH • ) radical scavenging activity assay; and Fe +3 -reducing power (ferric reducing antioxidant power assay, FRAP). Vitamin E and β-carotene contents were also quantified. All kefir samples exhibited varying values for DPPH, ABTS, and FRAP assays depending on the starter culture and milk type. Vitamin E and β-carotene contents were similar in all kefir samples during storage. The results of this study suggest that milk type (cow or ewe) and culture type (kefir grains or commercial starter) were the significant parameters for the antioxidative activity of kefir. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Antimicrobial and healing activity of kefir and kefiran extract.

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Rodrigues, Kamila Leite; Caputo, Lucélia Rita Gaudino; Carvalho, Jose Carlos Tavares; Evangelista, João; Schneedorf, Jose Maurício

2005-05-01

Kefir and its insoluble polysaccharide, kefiran, were both tested for antimicrobial and cicatrizing activities against several bacterial species and Candida albicans using an agar diffusion method. Comparator antimicrobials were also tested. Cicatrizing experiments were carried out on Wistar rats with induced skin lesions and Staphylococcus aureus inoculation, using a topical application of a 70% kefir gel. Both kefir and kefiran showed some activity against all organisms tested; the highest activity was against Streptococcus pyogenes. Cicatrizing experiments using 70% kefir gel had a protective effect on skin connective tissue and 7 days treatment enhanced wound healing compared with 5 mg/kg of neomycin-clostebol emulsion.

Antifungal effect of kefir fermented milk and shelf life improvement of corn arepas.

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Gamba, Raúl Ricardo; Caro, Carlos Andrés; Martínez, Olga Lucía; Moretti, Ana Florencia; Giannuzzi, Leda; De Antoni, Graciela Liliana; León Peláez, Angela

2016-10-17

Fungal contamination negatively affects the production of cereal foods such as arepa loaf, an ancient corn bread consumed daily in several countries of Latin-America. Chemical preservatives such as potassium sorbate are applied in order to improve the arepa's shelf life and to reduce the health risks. The use of natural preservatives such as natural fermented products in food commodities is a common demand among the consumers. Kefir is a milk fermented beverage obtained by fermentation of kefir grains. Its antibacterial and probiotic activity has been exhaustively demonstrated. Our objectives were to determine the antifungal effect of kefir fermented milk on Aspergillus flavus AFUNL5 in vitro and to study if the addition of kefir fermented milk to arepas could produce shelf life improvement. We determined the antifungal effect on solid medium of kefir cell-free supernatants (CFS) obtained under different fermentation conditions. Additionally, we compared the antifungal effect of kefir CFS with that obtained with unfermented milk artificially acidified with lactic plus acetic acids (lactic and acetic acids at the same concentration determined in kefir CFS) or with hydrochloric acid. Finally, kefir was added to the corn products either in the loaf recipe (kefir-baked arepas) or sprayed onto the baked-loaf surface (kefir-sprayed arepas). The loaves' resistance to natural and artificial fungal contamination and their organoleptic profiles were studied. The highest fungal inhibition on solid medium was achieved with kefir CFS produced by kefir grains CIDCA AGK1 at 100 g/L, incubated at 30 °C and fermented until pH 3.3. Other CFS obtained from different fermentation conditions achieved less antifungal activity than that mentioned above. However, CFS of milk fermented with kefir grains, until pH 4.5 caused an increase of growth rates. Additionally, CFS produced by kefir grains CIDCA AGK1 at 100 g/L, incubated at 30 °C and fermented until pH 3.3 achieved higher

"Petit suisse" cheese from kefir: an alternative dessert with microorganisms of probiotic activity Queijo "Petit suisse" de kefir: uma alternativa de sobremesa com microorganismos de ação probiótica

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Thanise Sabrina Souza Santos

2012-09-01

Full Text Available "Petit Suisse" is a creamy cheese. Kefir is a symbiotic mixture of lactic acid bacteria and yeasts with probiotic activity including immunomodulation and balance of intestinal microflora. The present study aims to develop "Petit Suisse" cheese from kefir. Kefir grains were grown in pasteurized cow milk, and after the separation of kefir the serum was discarded and the "Petit Suisse" cheese was prepared using strawberry, mangaba, herbs, and dried tomatoes. The acceptance of the different preparations was evaluated using a nine-point hedonic scale followed by ANOVA. The sweet and salty products were compared by the Student's t-test. Purchase intent was evaluated by the means test and frequency distribution. All products were well accepted by the judges. The product was characterized by low yield, but it can be prepared at home at low cost. The nutritional composition analyses and the variety of flavors as well as the range of age of the judges are alternatives for further studies.Petit suisse é um queijo de consistência pastosa. O kefir é um produto resultante da simbiose entre bactérias ácido-láticas e leveduras, e apresenta ação probiótica, como imunomodulação e balanço da microbiota intestinal. O presente estudo buscou desenvolver petit suisse de kefir. Os grãos foram cultivados no leite de vaca pasteurizado e, após separação do kefir, seguiu-se para dessoragem e preparo do petit suisse nos sabores morango, mangaba, ervas e tomate seco. Com escala hedônica estruturada de nove pontos, avaliou-se aceitação pela ANOVA. As amostras doces e salgadas foram comparadas por meio do teste t de Student e a intenção de compra foi avaliada por meio do teste de médias e de distribuição das frequências. As amostras apresentaram boa aceitação pelos julgadores. O produto pronto apresentou baixo rendimento, mas pode ser reproduzido em nível domiciliar com baixo custo. A análise da composição nutricional e a variação dos sabores e

Microbial Species Diversity, Community Dynamics, and Metabolite Kinetics of Water Kefir Fermentation

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Laureys, David

2014-01-01

Water kefir is a sour, alcoholic, and fruity fermented beverage of which the fermentation is started with water kefir grains. These water kefir grains consist of polysaccharide and contain the microorganisms responsible for the water kefir fermentation. In this work, a water kefir fermentation process was followed as a function of time during 192 h to unravel the community dynamics, the species diversity, and the kinetics of substrate consumption and metabolite production. The majority of the water kefir ecosystem was found to be present on the water kefir grains. The most important microbial species present were Lactobacillus casei/paracasei, Lactobacillus harbinensis, Lactobacillus hilgardii, Bifidobacterium psychraerophilum/crudilactis, Saccharomyces cerevisiae, and Dekkera bruxellensis. The microbial species diversities in the water kefir liquor and on the water kefir grains were similar and remained stable during the whole fermentation process. The major substrate, sucrose, was completely converted after 24 h of fermentation, which coincided with the production of the major part of the water kefir grain polysaccharide. The main metabolites of the fermentation were ethanol and lactic acid. Glycerol, acetic acid, and mannitol were produced in low concentrations. The major part of these metabolites was produced during the first 72 h of fermentation, during which the pH decreased from 4.26 to 3.45. The most prevalent volatile aroma compounds were ethyl acetate, isoamyl acetate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate, which might be of significance with respect to the aroma of the end product. PMID:24532061

Microbial species diversity, community dynamics, and metabolite kinetics of water kefir fermentation.

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Laureys, David; De Vuyst, Luc

2014-04-01

Water kefir is a sour, alcoholic, and fruity fermented beverage of which the fermentation is started with water kefir grains. These water kefir grains consist of polysaccharide and contain the microorganisms responsible for the water kefir fermentation. In this work, a water kefir fermentation process was followed as a function of time during 192 h to unravel the community dynamics, the species diversity, and the kinetics of substrate consumption and metabolite production. The majority of the water kefir ecosystem was found to be present on the water kefir grains. The most important microbial species present were Lactobacillus casei/paracasei, Lactobacillus harbinensis, Lactobacillus hilgardii, Bifidobacterium psychraerophilum/crudilactis, Saccharomyces cerevisiae, and Dekkera bruxellensis. The microbial species diversities in the water kefir liquor and on the water kefir grains were similar and remained stable during the whole fermentation process. The major substrate, sucrose, was completely converted after 24 h of fermentation, which coincided with the production of the major part of the water kefir grain polysaccharide. The main metabolites of the fermentation were ethanol and lactic acid. Glycerol, acetic acid, and mannitol were produced in low concentrations. The major part of these metabolites was produced during the first 72 h of fermentation, during which the pH decreased from 4.26 to 3.45. The most prevalent volatile aroma compounds were ethyl acetate, isoamyl acetate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate, which might be of significance with respect to the aroma of the end product.

Effects of kefir fractions on innate immunity.

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Vinderola, Gabriel; Perdigon, Gabriela; Duarte, Jairo; Thangavel, Deepa; Farnworth, Edward; Matar, Chantal

2006-01-01

Innate immunity that protects against pathogens in the tissues and circulation is the first line of defense in the immune reaction, where macrophages have a critical role in directing the fate of the infection. We recently demonstrated that kefir modulates the immune response in mice, increasing the number of IgA+ cells in the intestinal and bronchial mucosa and the phagocytic activity of peritoneal and pulmonary macrophages. The aim of this study was to further characterize the immunomodulating capacity of the two fractions of kefir (F1: solids including bacteria and F2: liquid supernatant), by studying the cytokines produced by cells from the innate immune system: peritoneal macrophages and the adherent cells from Peyer's patches. BALB/c mice were fed either kefir solid fraction (F1) or kefir supernatant (F2) for 2, 5 or 7 consecutive days. The number of cytokine (IL-1alpha, IFNgamma, TNFalpha, IL-6 and IL-10) producing cells was determined on peritoneal macrophages and adherent cells from Peyer's patches. Both kefir fractions (F1 and F2) induced similar cytokine profiles on peritoneal macrophages (only TNFalpha and IL-6 were up-regulated). All cytokines studied on adherent cells from Peyer's patches were enhanced after F1 and F2 feeding, except for IFNgamma after F2 administration. Moreover, the percentage of IL-10+cells induced by fraction F2 on adherent cells from Peyer's patches was significantly higher than the one induced by fraction F1. Different components of kefir have an in vivo role as oral biotherapeutic substances capable of stimulating immune cells of the innate immune system, to down-regulate the Th2 immune phenotype or to promote cell-mediated immune responses against tumours and also against intracellular pathogenic infections.

Evaluation of the subchronic toxicity of kefir by oral administration in Wistar rats.

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Diniz Rosa, Damiana; Gouveia Peluzio, Maria do Carmo; Pérez Bueno, Tania; Vega Cañizares, Ernesto; Sánchez Miranda, Lilian; Mancebo Dorbignyi, Betty; Chong Dubí, Dainé; Espinosa Castaño, Ivette; Marcin Grzes Kowiak, Lukasz; Fortes Ferreira, Célia Lucia de Luces

2014-06-01

Kefir is obtained by fermentation of milk with complex microbial populations present in kefir grains. Several health-promoting benefits have been attributed to kefir consumption. The objective of this work was to conduct a subchronic toxicity study, offering the rats normal or high-doses of kefir and evaluating growth, hematology and blood chemistry, as well as assessing bacterial translocation and the integrity of the intestinal mucosa of animals. Wistar rats were randomly divided into three groups (n = 6/group): control group received 0.7 mL of water, kefir group received 0.7 mL/day of kefir, (normodose), and Hkefir group received 3.5 mL/day of kefir (fivefold higher dose). Feeding was carried out by gavage. The animals were housed in individual cages and maintained under standard conditions for 4 weeks. The normodose and high-dose of kefir supplementation did not harm the animals since growth, hematology and blood chemistry in rats, as well as the potential pathogenicity in tissues were within normal limits, demonstrating that consumption of normodose and highdose of kefir are safe. In addition, administration of the normodose of kefir reduced cholesterol levels and improved the intestinal mucosa of the rats. These results demonstrate that the consumption of kefir is safe. Importantly, while damages are not seen for the high-dose, the normodose consumption is recommended due to the pronounced beneficial effects, as safety is concerned. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

The antiallergic effect of kefir Lactobacilli.

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Hong, Wei-Sheng; Chen, Yen-Po; Chen, Ming-Ju

2010-10-01

This study demonstrated that oral feeding of heat-inactivated Lactobacillus (L b.) kefiranofaciens M1 from kefir grains effectively inhibited immunoglobulin (Ig) E production in response to ovalbumin (OVA) in vivo. The pattern of cytokine production by splenocyte cells revealed that the levels of cytokines produced by T helper (Th) 1 cells increased, and those of cytokines produced by Th2 cells decreased in the heat-inactivated M1 feeding group. These findings indicated that Lactobacillus kefiranofaciens M1 in the kefir played an important role in antiallergic activities. By additional analysis using flow cytometry and microarray, the mechanism of suppression of IgE production by oral feeding of the heat-inactivated M1 probably occurs because of upregulation of the expression of Cd2, Stat4, and Ifnr leading to skewing the Th1/Th2 balance toward Th1 dominance, elevation of the CD4(+)CD25(+) regulatory T (Treg) percentage, and reduction of activated CD19(+) B cells. Downregulation of complement system and components was also involved in suppression of IgE production. Practical Application: Kefir has long been considered good for health. Its health benefits include immunoregulatory effects. However, there is a lack of knowledge concerning the immunoregulatory effects induced by kefir lactic acid bacteria (LAB). Our data clearly demonstrated the antiallergic activity of kefir LAB, Lactobacillus (L b.) kefiranofaciens M1. By additional analysis using flow cytometry and microarray, the possible mechanism of suppression of IgE production by oral feeding of the heat-inactivated M1 was also elucidated. Our findings indicated that Lactobacillus kefiranofaciens M1 may have a great potential for utilization in functional food products.

The Antimetastatic and Antiangiogenesis Effects of Kefir Water on Murine Breast Cancer Cells.

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Zamberi, Nur Rizi; Abu, Nadiah; Mohamed, Nurul Elyani; Nordin, Noraini; Keong, Yeap Swee; Beh, Boon Kee; Zakaria, Zuki Abu Bakar; Nik Abdul Rahman, Nik Mohd Afizan; Alitheen, Noorjahan Banu

2016-12-01

Kefir is a unique cultured product that contains beneficial probiotics. Kefir culture from other parts of the world exhibits numerous beneficial qualities such as anti-inflammatory, immunomodulation, and anticancer effects. Nevertheless, kefir cultures from different parts of the world exert different effects because of variation in culture conditions and media. Breast cancer is the leading cancer in women, and metastasis is the major cause of death associated with breast cancer. The antimetastatic and antiangiogenic effects of kefir water made from kefir grains cultured in Malaysia were studied in 4T1 breast cancer cells. 4T1 cancer cells were treated with kefir water in vitro to assess its antimigration and anti-invasion effects. BALB/c mice were injected with 4T1 cancer cells and treated orally with kefir water for 28 days. Kefir water was cytotoxic toward 4T1 cells at IC 50 (half-maximal inhibitory concentration) of 12.5 and 8.33 mg/mL for 48 and 72 hours, respectively. A significant reduction in tumor size and weight (0.9132 ± 0.219 g) and a substantial increase in helper T cells (5-fold) and cytotoxic T cells (7-fold) were observed in the kefir water-treated group. Proinflammatory and proangiogenic markers were significantly reduced in the kefir water-treated group. Kefir water inhibited tumor proliferation in vitro and in vivo mainly through cancer cell apoptosis, immunomodulation by stimulating T helper cells and cytotoxic T cells, and anti-inflammatory, antimetastatic, and antiangiogenesis effects. This study brought out the potential of the probiotic beverage kefir water in cancer treatment. © The Author(s) 2016.

Pengaruh pati ganyong (Cannaedulis, Ker modifikasi terhadap kualitas kefir

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Imam Thohari

2014-07-01

Full Text Available The purpose of the research was to determine the effect of using various concentration of modification starch on pH, water content, viscosity and fat content. The research material were kefir made from cow's milk with kefir grains derived from animal product technology laboratory of Animal Husbandry Brawijaya University. The research method was an experimental research with randomized block design. The treatments were the addition of canna starch modification 0% (G0, 0.2% (G1, 0.4% (G2, 0.6% (G3, 0.8% (G4 and 1.0% (G5 of the milk volume. Each treatment was replicated 3 times. The result showed that the addition of modified canna starch provided highly significant effect (p<0.01 on pH, water content, viscosity and fat content. The study concluded that addition of canna starch modification could improve the quality of kefir in terms of pH, water content, and viscosity, protein and lactic acid bacteria. The addition of 1% of canna starch modification had the best kefir quality. Keywords: Kefir, canna starch modification, STTP

Kefir: a New Role as Nutraceuticals

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Setyowati, Hanny; setyani, Wahyuning

2016-01-01

Nutraceutical is the fusion of “nutrition” and pharmaceutical”. This products, in broad, are food or part of food that provides medical or health benefits including the prevention and or treatment of a disease. Kefir is renowned nutraceutical dairy products produced through fermentation of bacteria and yeasts and naturally present in grains of kefir. The nutritional attributes are due to presence of vital nutrients such as carbohydrates, amino acids, proteins, minerals, phosphorus, vitamin, c...

Kefir prevented excess fat accumulation in diet-induced obese mice.

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Choi, Jae-Woo; Kang, Hye Won; Lim, Won-Chul; Kim, Mi-Kyoung; Lee, In-Young; Cho, Hong-Yon

2017-05-01

Excessive body fat accumulation can result in obesity, which is a serious health concern. Kefir, a probiotic, has recently shown possible health benefits in fighting obesity. This study investigated the inhibitory effects of 0.1 and 0.2% kefir powder on fat accumulation in adipose and liver tissues of high-fat diet (HFD)-induced obese mice. Kefir reduced body weight and epididymal fat pad weight and decreased adipocyte diameters in HFD-induced obese mice. This was supported by decreased expression of genes related to adipogenesis and lipogenesis as well as reduced proinflammatory marker levels in epididymal fat. Along with reduced hepatic triacylglycerol concentrations and serum alanine transaminase and aspartate transaminase activities, genes related to lipogenesis and fatty acid oxidation were downregulated and upregulated, respectively, in liver tissue. Kefir also decreased serum triacylglycerol, total cholesterol, and low-density lipoprotein-cholesterol concentrations. Overall, kefir has the potential to prevent obesity.

Kandungan beta karoten, polifenol total dan aktifitas ”merantas” radikal bebas kefir susu kacang hijau (Vigna radiata oleh pengaruh jumlah starter (Lactobacillus bulgaricus dan Candida kefir dan konsentrasi glukosa

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Teguh Supriyono

2014-06-01

Full Text Available Background: Kefir is a well known fermented dairy milk product which is functional for gut health. However kefir can also be made from vegetable milk such as soy or mungbean milk. Objective: To study the chemical  and functional property of Mungbean milk (MBM Kefir Methods:Mungbean milk was fermented into MBM Kefir using Lactobacillus bulgaricus and Candida kefir. Three levels of cultures and glucose concentration were tested and a complete randomized design experiment was employed. The resulting MBM Kefir were tested for β-carotene level, total polyphenol content, and free radical scavenging activity. Beta carotene level, total polyphenols and free radicals scavenging activity were determined by spectrophotometry, Folin-Ciocalteu method, and DPPH radical scavenging assay respectively. The data were analyzed by ANOVA and when the result of ANOVA was significant, Tukey’s multiple comparison was conducted. Results: Culture concentration increased  β-carotene level (p = 0.049, total polyphenol (p = 0.015 and free radical scavenging activity (p = 0,000 of MBM kefir. Glucose concentration increased total polyphenol (p = 0.002, but had no effect on free radical scavenging activity and β-carotene level. However, there were no interaction among treatments at 0.05 significance level. Total acid level ranged from 1.57 to 2.54%, with the highest and level at 15% cultures concentration and 15% glucose concentration. Alcohol level ranged from 0.26 to 0.90% which was in accordance with the maximum standard for kefir (1%. Conclusion: An optimal product of mungbean milk kefir with highest free radical scavenging activity can be obtained using 15% cultures (Lactobacillus bulgaricus and Candida kefir and 10% glucose concentration.

The Microbiota and Health Promoting Characteristics of the Fermented Beverage Kefir.

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Bourrie, Benjamin C T; Willing, Benjamin P; Cotter, Paul D

2016-01-01

Kefir is a complex fermented dairy product created through the symbiotic fermentation of milk by lactic acid bacteria and yeasts contained within an exopolysaccharide and protein complex called a kefir grain. As with other fermented dairy products, kefir has been associated with a range of health benefits such as cholesterol metabolism and angiotensin-converting enzyme (ACE) inhibition, antimicrobial activity, tumor suppression, increased speed of wound healing, and modulation of the immune system including the alleviation of allergy and asthma. These reports have led to increased interest in kefir as a focus of research and as a potential probiotic-containing product. Here, we review those studies with a particular emphasis on the microbial composition and the health benefits of the product, as well as discussing the further development of kefir as an important probiotic product.

Peptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins.

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Dallas, David C; Citerne, Florine; Tian, Tian; Silva, Vitor L M; Kalanetra, Karen M; Frese, Steven A; Robinson, Randall C; Mills, David A; Barile, Daniela

2016-04-15

The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins. Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species. The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases. Copyright © 2015 Elsevier Ltd. All rights reserved.

Peptidomic analysis reveals proteolytic activity of kefir microorganisms on bovine milk proteins

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Dallas, David C.; Citerne, Florine; Tian, Tian; Silva, Vitor L. M.; Kalanetra, Karen M.; Frese, Steven A.; Robinson, Randall C.; Mills, David A.; Barile, Daniela

2015-01-01

Scope The microorganisms that make up kefir grains are well known for lactose fermentation, but the extent to which they hydrolyze and consume milk proteins remains poorly understood. Peptidomics technologies were used to examine the proteolytic activity of kefir grains on bovine milk proteins. Methods and results Gel electrophoresis revealed substantial digestion of milk proteins by kefir grains, with mass spectrometric analysis showing the release of 609 protein fragments and alteration of the abundance of >1,500 peptides that derived from 27 milk proteins. Kefir contained 25 peptides identified from the literature as having biological activity, including those with antihypertensive, antimicrobial, immunomodulatory, opioid and anti-oxidative functions. 16S rRNA and shotgun metagenomic sequencing identified the principle taxa in the culture as Lactobacillus species. Conclusion The model kefir sample contained thousands of protein fragments released in part by kefir microorganisms and in part by native milk proteases. PMID:26616950

The Microbiota and health promoting characteristics of the fermented beverage Kefir.

Directory of Open Access Journals (Sweden)

Benjamin C.T. Bourrie

2016-05-01

Full Text Available Kefir is a complex fermented dairy product created through the symbiotic fermentation of milk by lactic acid bacteria and yeasts contained within an exopolysaccharide and protein complex called a kefir grain. As with other fermented dairy products, kefir has been associated with a range of health benefits such as cholesterol metabolism and angiotensin-converting enzyme (ACE inhibition, antimicrobial activity, tumor suppression, increased speed of wound healing, and modulation of the immune system including the alleviation of allergy and asthma. These reports have led to increased interest in kefir as a focus of research and as a potential probiotic-containing product. Here, we review those studies with a particular emphasis on the microbial composition and the health benefits of the product, as well as discussing the further development of kefir as an important probiotic product.

The Microbiota and Health Promoting Characteristics of the Fermented Beverage Kefir

Science.gov (United States)

Bourrie, Benjamin C. T.; Willing, Benjamin P.; Cotter, Paul D.

2016-01-01

Kefir is a complex fermented dairy product created through the symbiotic fermentation of milk by lactic acid bacteria and yeasts contained within an exopolysaccharide and protein complex called a kefir grain. As with other fermented dairy products, kefir has been associated with a range of health benefits such as cholesterol metabolism and angiotensin-converting enzyme (ACE) inhibition, antimicrobial activity, tumor suppression, increased speed of wound healing, and modulation of the immune system including the alleviation of allergy and asthma. These reports have led to increased interest in kefir as a focus of research and as a potential probiotic-containing product. Here, we review those studies with a particular emphasis on the microbial composition and the health benefits of the product, as well as discussing the further development of kefir as an important probiotic product. PMID:27199969

Microbiological, biochemical, and functional aspects of sugary kefir fermentation - A review.

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Fiorda, Fernanda Assumpção; de Melo Pereira, Gilberto Vinicius; Thomaz-Soccol, Vanete; Rakshit, Sudip Kumar; Pagnoncelli, Maria Giovana Binder; Vandenberghe, Luciana Porto de Souza; Soccol, Carlos Ricardo

2017-09-01

Sugary kefir beverage is produce by fermenting raw sugar solution with kefir grains, the latter consisting of polysaccharide and microorganisms. This beverage, with great consumption in countries such as USA, Japan, France, and Brazil, represents a promising market to functional cultured drinks. This paper reviews the microbial diversity and interaction, kinetics, safety, and bioactivities of sugary kefir fermentation. The literature reviewed here demonstrates that sugary kefir possesses a similar microbial association relative to traditional milk kefir fermentation, especially among lactic acid bacteria and yeast species, such as Lactobacillus, Leuconostoc, Kluyveromyces, Pichia, and Saccharomyces. However, a selective pressure at species level is generally observed, as, for example, the stimulation of Saccharomyces species metabolism, leading to a high content of alcohol in the final product. This also seems to stimulate the growth of acetic acid bacteria that benefit of increased ethanol production to acetic acid metabolism. Existing reports have suggested important bioactivities associated with sugary kefir beverage consumption, such as antimicrobial, antiedematogenic, anti-inflammatory, antioxidant, cicatrizing, and healing activities. Other alternative non-dairy substrates, such as fruits, vegetables, and molasses, have also been tested for adaptation of kefir grains and production of functional beverages with distinct sensory characteristics. This diversification is of crucial importance for the production of new probiotic products to provide people with special needs (lactose intolerance) and vegan consumers. Copyright © 2017 Elsevier Ltd. All rights reserved.

KARAKTERISTIK FISIK, KIMIA, MIKROBIOLOGI WHEY KEFIR DAN AKTIVITASNYA TERHADAP PENGHAMBATAN ANGIOTENSIN CONVERTING ENZYME (ACE [Physical, Chemical and Microbiological Characteristics of Whey Kefir and Its Angiotensin Converting Enzyme (ACE Inhibitory Activity

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Andi Febrisiantosa*

2013-12-01

Full Text Available This study was conducted to evaluate the characteristics of whey-based kefir products and their activity to inhibit the angiotensin converting enzyme (ACE. Kefir was produced by using many types of whey, namely SK: skim milk based kefir (control; WK: gouda cheese whey based kefir; and WKB: commercial whey powder based kefir. The experimental design was a completely randomized design. Each treatment was conducted in triplicates. Kefirs were evaluated for physical and chemical properties (pH, total titratable acidity, viscosity, protein, fat, lactose, and alcohol, microbiological (lactic acid bacteria and yeast population, peptide concentration, ACE inhibition, IC50 and Inhibition Efficiency Ratio (IER. The results showed that the types of whey used for kefir productions significantly affected the physical and chemical characteristics of the products (p0.05. The peptide concentration and ACE inhibitory activity of WK, 1.54±0.02 mg/mL and 73.07±0.91%, was significantly higher (p0.05 from the control (47.19±0.09% per mg/mL but was significantly higher (p<0.05 than that of WKB (45.75±0.18% per mg/mL. This research indicated that whey kefir is a potential source of bioactive peptide for antihypertention agent.

Identification of some kefir microorganisms and optimization of their production in sugarcane juice

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Blanca Cecilia Salazar Alzate

2016-07-01

Full Text Available Kefir grains are a consortium of bacteria and yeasts grouped in a polysaccharide called kefirano. They ferment sugar substrates to produce organic acids, CO2, vitamins and ethanol. They also have positive effects on health. This research project aimed to optimize the fermentation process of sugarcane concentrate using kefir grains. The microorganisms were first identified morphologically and biochemically, then isolated and purified in selective media. Optimization was conducted using the response surface methodology with a composite central design. The independent variables were: temperature, time and percentage of kefir grains added. As for dependent variables, we considered the following: increase in kefir grains (also measured as a percentage, acidity and microbial growth. Additionally, our study identified populations of Lactobacillus curvatus and the following yeasts: Candida famata, Can. magnoliae, Can. krusei/incospicua and Can. sphaerica in the kefir grains. The optimal conditions were 33.5 °C, 30 h and 6% w/w of added kefir grains. The increase in kefir grains reached was of 193 ± 12%. The lactobacilli, lactococci and yeast counts were 1.57x108, 8.63x107 and 2.05x107 CFU mL-1 respectively. Experimental optimization was an effective tool for the fermentation of kefir grains in sugarcane concentrate.

Performance of Holstein calves fed whole milk with or without kefir.

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Fouladgar, S; Shahraki, A D Foroozandeh; Ghalamkari, G R; Khani, M; Ahmadi, F; Erickson, P S

2016-10-01

A growing body of evidence suggests health-promoting effects of kefir consumption on different nonruminant species, leading to the speculation that kefir may act as a probiotic and benefit calf performance and health. Our objectives were to determine effects of feeding kefir on performance and health of calves in the first 70d of life. Thirty 3-d-old female Holstein calves (body weight=38.2±3.1kg) were blocked by initial body weight and assigned randomly to 1 of 3 treatments (1 calf per pen; 10 pens per treatment). Kefir was added to whole milk (vol/vol) at 0:1 (control; KF0), 1:3 (KF1), or 1:1 (KF2) and fed twice per day (0800 and 1600h) from d3 through 45 and then once per day until weaning, which occurred on d50. Pre- and postweaning intake of starter, daily body weight gain, and gain-to-feed ratio exhibited no difference among treatments. Adding kefir to whole milk fed directly to calves had no effect on concentration of blood metabolites collected on d20, 40, and 70. Body length on d50 (weaning) and 70 was greater in kefir-fed calves. Kefir intake improved fecal scores and reduced days with diarrhea during the first 2wk of life. Apparent digestibility of organic matter, ether extract, crude protein, and neutral detergent fiber remained unaffected by treatment. Overall, it appears that directly feeding kefir to calves during the preweaning period did not improve the performance of calves under the conditions of the current study; however, its consumption marginally improved body length and fecal consistency in the first weeks of life, which is an important concern in intensive calf-rearing systems. Feeding kefir to neonatal calves may be a viable approach to improve the health of calves in commercial calf-rearing operations, although to validate its health-promoting effects additional research is needed to investigate its effects under different calf-rearing conditions. Copyright © 2016 American Dairy Science Association. Published by Elsevier Inc. All rights

The effect of kefir starter on Thai fermented sausage product

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Marisa Jatupornpipat

2007-07-01

Full Text Available The effect of kefir starter from Wilderness Family Naturals Company on the initial formulation of Thai fermented sausage were evaluated. The differences found among batches in the main microbial populations and pH were not significant. Only, the total acid of batch D (added the kefir starter 15 ml was significantly higher (P0.05. It is concluded that the addition of kefir starter (7 ml could be useful to improve the final quality of Thai fermented sausages. The addition of kefir starter that initiates rapid acidification of the raw meat and that leads to a desirable sensory quality of the end-product are used for the production of fermented sausages, and represents a way of improving and optimizing the sausage fermentation process and achieving tastier, safer, and healthier products.

Growth Inhibition of Cronobacter sakazakii in Experimentally Contaminated Powdered Infant Formula by Kefir Supernatant.

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Kim, Dong-Hyeon; Chon, Jung-Whan; Kang, Il-Byeong; Kim, Hyunsook; Kim, Hong-Seok; Song, Kwang-Young; Seo, Kun-Ho

2015-09-01

Kefir is a type of fermented milk containing lactic and acetic acid bacteria and yeast. In this study, we evaluated the antimicrobial activity of kefir supernatant against Cronobacter sakazakii in powdered infant formula (PIF). In a spot-on-lawn test, the growth of 20 C. sakazakii strains, including 10 clinical and 10 food isolates, was completely inhibited in the presence of kefir supernatant. Significant differences in the diameters of inhibition zones were observed upon treatment with kefir compared with the results for Lactobacillus kefiri and Candida kefyr culture supernatants or solutions of lactic and acetic acid and ethyl alcohol in the agar well diffusion test (P < 0.05). The addition of 100 μl of kefir supernatant to 1 ml of nutrient broth completely inhibited the growth of C. sakazakii, as evaluated by spectrophotometry. The antimicrobial activity of kefir supernatant in experimentally contaminated PIF was also tested; we found no viable C. sakazakii cells remaining in PIF rehydrated with 30% kefir supernatant solution for 1 h, demonstrating that the antimicrobial activity of kefir supernatant against C. sakazakii could be applied in real food samples.

Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

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Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

2011-01-01

Background: Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. Conclusion: In conclusion, kefir is

Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

International Nuclear Information System (INIS)

Maalouf, Katia; Baydoun, Elias; Rizk, Sandra

2011-01-01

Adult lymphoblastic leukemia (ALL) is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer. The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1)-negative malignant T-lymphocytes. Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α), transforming growth factor- beta1 (TGF-β1), matrix metalloproteinase-2 (MMP-2), and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR). Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA) and flow cytometry. The maximum cytotoxicity recorded after 48-hours treatment with 80 μg/μL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF-β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG 1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was further confirmed by Cell Death Detection ELISA. However, kefir did not affect the mRNA expression of metalloproteinases needed for the invasion of leukemic cell lines. In conclusion, kefir is effective in inhibiting proliferation and inducing

An innovative approach: cow/oat milk based kefir

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Nayil Dinkçi

2015-07-01

Full Text Available The aim of this study was to evaluate the potential of kefir production using cow-oat milk mixture. Therefore kefir samples with 20, 40 and 60 % of oat milk were produced. The effect of oat-milk ratio on physicochemical, rheological, microbiological and sensory characteristics of the kefir samples was studied during 21 days storage at refrigerated conditions. Increasing oat milk concentration affected the whey-off and apparent viscosity by higher whey off and lower viscosity results. Also the proteolytic activity of the samples was decreased by raising the oat milk concentrations. Increase of the oat milk concentration leaded to a decrease of pH of the samples. Statistical analysis showed that the lactococci and lactobacilli viable cell counts differed among the samples while the highest count was detected in sample with the highest amount of oat milk. The control sample (without oat milk had higher yeast count during the storage period. The final product with 20 % of oat-milk and without addition of flavour was found to be the most acceptable by the sensory panellists. The results indicate the possibility for a new cow/oat milk based kefir.

KEFIRS MANUFACTURED FROM CAMEL (CAMELUS DRAMEDARIUS MILK AND COW MILK: COMPARISON OF SOME CHEMICAL AND MICROBIAL PROPERTIES

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G. Kavas

2015-09-01

Full Text Available This study examined the production possibilities of kefir from fresh camel milk fermented with grain. The findings were then compared with kefir manufactured from cow’s milk. Cow’s milk was fermented with 2.5% grains. The 1% (v/w glucose enriched camel’s milk was fermented with 10% grains and left in an incubator at 25°C. Physical-chemical and sensorial analyses of the kefir sampleswere measured on day one (18 hours of storage and microbiological analyses were measured on days one, three and five. Some physical-chemical parameters were found to be higherin camel milk and its kefir than in cow milk and its kefir, some were found to be close and some were found to be lower. Addition of 1% glucose and 10% grains to the camel milk affected the titrationacidity and viscosity of kefir to significant levels. The kefir produced from camel milk was perceived as sourer, whereas its other properties were found to be close to those of cow milk. Thecholesterol levels of camel milk and its kefir were detected to be higher when compared to those of cow milk and its kefir, but the cholesterol level decreased in both examples after the productionof kefir. In terms of the composition of fatty acids, it was determined that SFA and the small, medium chain fatty acids ratio was low in camel milk and its kefir, but MUFA and the long chainfatty acids ratio was high. PUFA ratio was high in camel milk but low in its kefir. In microbiological analysis, yeast levels increased in kefir samples with the Lactobacillus ssp. strains, and theincrease in the number of yeasts was higher than in the cow milk kefir. In kefir samples, Lactobacillus ssp. strains increased on day one and three of storage, but diminished after day three.

Fermentation process for production of apple-based kefir vinegar: microbiological, chemical and sensory analysis

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Roberta Oliveira Viana

Full Text Available Abstract The aim of this study was to develop a kefir apple-based vinegar and evaluate this fermentation process using new methodology with Biospeckle Laser. Brazilian kefir grains were inoculated in apple must for vinegar production. In this study, the microbial community present in kefir, and correspondent vinegar, was investigated using Matrix Assisted Laser Desorption/Ionization - Time of Flight Mass Spectrometry (MALDI-TOF MS technique. Saccharomyces cerevisiae, Lactobacillus paracasei, Lactobacillus plantarum, Acetobacter pasteurianus and Acetobacter syzygii were the microbial species identified. S. cerevisiae, L. plantarum, A. pasteurianus and A. syzygii were found in smaller quantities at the beginning of the alcoholic fermentation, but were found throughout the alcoholic and acetic fermentation. Kefir grains were able to utilize apple must as substrate to produce ethanol, and acetic acid. Acetate, volatile alcohols and aldehydes in the vinegar-based kefir were also produced. The yield of acetic acid in the kefir vinegars was ∼79%. The acetic acid concentration was ∼41 g L-1, reaching the required standard for the Brazilian legislation accepts it as vinegar (4.0% acetic acid. Kefir vinegar showed good acceptance in the sensory analysis. The technology proposed here is novel by the application of immobilized-cell biomass (kefir grains providing a mixed inocula and eliminating the use of centrifuge at the end of the fermentative process. This step will save energy demand and investment. This is the first study to produce apple vinegar using kefir grains.

Fermentation process for production of apple-based kefir vinegar: microbiological, chemical and sensory analysis.

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Viana, Roberta Oliveira; Magalhães-Guedes, Karina Teixeira; Braga, Roberto Alves; Dias, Disney Ribeiro; Schwan, Rosane Freitas

The aim of this study was to develop a kefir apple-based vinegar and evaluate this fermentation process using new methodology with Biospeckle Laser. Brazilian kefir grains were inoculated in apple must for vinegar production. In this study, the microbial community present in kefir, and correspondent vinegar, was investigated using Matrix Assisted Laser Desorption/Ionization - Time of Flight Mass Spectrometry (MALDI-TOF MS) technique. Saccharomyces cerevisiae, Lactobacillus paracasei, Lactobacillus plantarum, Acetobacter pasteurianus and Acetobacter syzygii were the microbial species identified. S. cerevisiae, L. plantarum, A. pasteurianus and A. syzygii were found in smaller quantities at the beginning of the alcoholic fermentation, but were found throughout the alcoholic and acetic fermentation. Kefir grains were able to utilize apple must as substrate to produce ethanol, and acetic acid. Acetate, volatile alcohols and aldehydes in the vinegar-based kefir were also produced. The yield of acetic acid in the kefir vinegars was ∼79%. The acetic acid concentration was ∼41gL -1 , reaching the required standard for the Brazilian legislation accepts it as vinegar (4.0% acetic acid). Kefir vinegar showed good acceptance in the sensory analysis. The technology proposed here is novel by the application of immobilized-cell biomass (kefir grains) providing a mixed inocula and eliminating the use of centrifuge at the end of the fermentative process. This step will save energy demand and investment. This is the first study to produce apple vinegar using kefir grains. Copyright © 2017. Published by Elsevier Editora Ltda.

Biological activity of the non-microbial fraction of kefir: antagonism against intestinal pathogens.

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Iraporda, Carolina; Abatemarco Júnior, Mário; Neumann, Elisabeth; Nunes, Álvaro Cantini; Nicoli, Jacques R; Abraham, Analía G; Garrote, Graciela L

2017-08-01

Kefir is a fermented milk obtained by the activity of kefir grains which are composed of lactic and acetic acid bacteria, and yeasts. Many beneficial health effects have been associated with kefir consumption such as stimulation of the immune system and inhibition of pathogenic microorganisms. The biological activity of kefir may be attributed to the presence of a complex microbiota as well as the microbial metabolites that are released during fermentation. The aim of this work was to characterise the non-microbial fraction of kefir and to study its antagonism against Escherichia coli, Salmonella spp. and Bacillus cereus. During milk fermentation there was a production of organic acids, mainly lactic and acetic acid, with a consequent decrease in pH and lactose content. The non-microbial fraction of kefir added to nutrient broth at concentrations above 75% v/v induced a complete inhibition of pathogenic growth that could be ascribed to the presence of un-dissociated lactic acid. In vitro assays using an intestinal epithelial cell model indicated that pre-incubation of cells with the non-microbial fraction of kefir did not modify the association/invasion of Salmonella whereas pre-incubation of Salmonella with this fraction under conditions that did not affect their viability significantly decreased the pathogen's ability to invade epithelial cells. Lactate exerted a protective effect against Salmonella in a mouse model, demonstrating the relevance of metabolites present in the non-microbial fraction of kefir produced during milk fermentation.

MILK KEFIR: COMPOSITION, MICROBIAL CULTURES, BIOLOGICAL ACTIVITIES AND RELATED PRODUCTS

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Maria Rosa Prado

2015-10-01

Full Text Available In recent years, there has been a strong focus on beneficial foods with probiotic microorganisms and functional organic substances. In this context, there is an increasing interest in the commercial use of kefir, since it can be marketed as a natural beverage that has health promoting bacteria. There are numerous commercially available kefir based-products. Kefir may act as a matrix in the effective delivery of probiotic microorganisms in different types of products. Also, the presence of kefir’s exopolysaccharides, known as kefiran, which has biological activity, certainly adds value to products. Kefiran can also be used separately in other food products and as a coating film for various food and pharmaceutical products. This article aims to update the information about kefir and its microbiological composition, biological activity of the kefir’s microflora and the importance of kefiran as a beneficial health substance.

Gastroprotective effect of kefir on ulcer induced in irradiated rats.

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Fahmy, Hanan A; Ismail, Amel F M

2015-03-01

The current study was designed to investigate the protective effect of kefir milk on ethanol-induced gastric ulcers in γ-irradiated rats. The results of the present study revealed that treatment with γ-irradiation and/or ethanol showed a significant increase in ulcers number, total acidity, peptic, H(+)K(+)ATPase, MMP-2 and MMP-9 activities and MDA level, which were accompanied by a significant decrease in the mucus content, the stomach GSH level, the GSH-Px activity and DNA damage. Pre-treatment with kefir milk exert significant improvement in all the tested parameters. Kefir milk exerts comparable effect to that of the antiulcer drug ranitidine. In conclusion, the present study revealed that oral administration of kefir milk prevents ethanol-induced gastric ulcer in γ-irradiated rats that could attribute to its antioxidant, anti-apoptotic and radio-protective activities. Copyright © 2015 Elsevier B.V. All rights reserved.

Comparative study of microbiological, chemical and sensory properties of kefirs produced in Estonia, Latvia and Lithuania.

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Anton, Dea; Raudsepp, Piret; Roasto, Mati; Meremäe, Kadrin; Kuusik, Sirje; Toomik, Peeter; Elias, Priit; Laikoja, Katrin; Kaart, Tanel; Lepiku, Martin; Püssa, Tõnu

2016-02-01

In the current study the microbiological, sensory and chemical properties of 24 kefirs (12 producers) from Estonian, Latvian and Lithuanian retail market were determined using gas chromatography (GC), high performance liquid chromatography (HPLC-MS/MS-Q-TOF and LC-ion trap MS/MS), spectrophotometry and other methods. Antihypertensive, angiotensin-converting enzyme (ACE) inhibiting, antioxidant and antibacterial peptides were found in the kefir samples. According to the results of principal component analysis of 200 most abundant compounds obtained with HPLC-MS/MS-Q-TOF analysis, Estonian kefirs differed from the rest. Kefirs of Latvian and Lithuanian origin showed similarities in several characteristics, probably related to the starter cultures and technological processes. The fatty acids composition of all Baltic kefirs was uniform. The antioxidant capacity of the kefirs varied slightly, whereas intermediate positive correlation (r = 0.32, P kefirs. Only one third of analysed kefirs met the requirements of the minimum sum of viable microorganisms, indicated in the Codex Standard for Fermented Milks.

Antidiabetic Potential of Kefir Combination from Goat Milk and Soy Milk in Rats Induced with Streptozotocin-Nicotinamide

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Harmayani, Eni; Sunarti

2015-01-01

The study aimed to evaluate the effect of kefir combination from goat milk and soy milk on lipid profile, plasma glucose, glutathione peroxidase (GPx) activity and the improvement of pancreatic β-cell in diabetic rats. Male rats were divided into five treatments: normal control, diabetic control, goat milk kefir, combination of goat milk-soy milk kefir and soy milk kefir. All rats were induced by streptooztocin-nicotinamide (STZ-NA), except for normal control. After 35 d experiment, the rats were sampled for blood, sacrificed and sampled for pancreatic tissues. Results showed that diabetic rats fed kefir combination had higher (p<0.05) triglyceride than the rats fed goat milk or soy milk kefir. Decreasing of plasma glucose in diabetic rats fed kefir combination was higher (p<0.05) than rats fed goat millk kefir. The activity of GPx in diabetic rats fed three kinds of kefir were higher (p<0.01) than untreated diabetic rats. The average number of Langerhans and β-cells in diabetic rats fed kefir combination was the same as the normal control, but it was higher than diabetic control. It was concluded that kefir combination can be used as antidiabetic through maintaining in serum triglyceride, decreasing in plasma glucose, increasing in GPx activity and improving in pancreatic β-cells. PMID:26877646

Kefir induces cell-cycle arrest and apoptosis in HTLV-1-negative malignant T-lymphocytes

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Katia Maalouf

2011-02-01

Full Text Available Katia Maalouf1, Elias Baydoun2, Sandra Rizk11Department of Natural Sciences, Lebanese American University, Beirut, Lebanon; 2Department of Biology, American University of Beirut, Beirut, LebanonBackground: Adult lymphoblastic leukemia (ALL is a malignancy that occurs in white blood cells. The overall cure rate in children is 85%, whereas it is only 40% in adults. Kefir is an important probiotic that contains many bioactive ingredients, which give it unique health benefits. It has been shown to control several cellular types of cancer.Purpose: The present study investigates the effect of a cell-free fraction of kefir on CEM and Jurkat cells, which are human T-lymphotropic virus type I (HTLV-1-negative malignant T-lymphocytes.Methods: Cells were incubated with different kefir concentrations. The cytotoxicity of the compound was evaluated by determining the percentage viability of cells. The effect of all the noncytotoxic concentrations of kefir on the proliferation of CEM and Jurkat cells was then assessed. The levels of transforming growth factor-alpha (TGF-α, transforming growth factor- beta1 (TGF-β1, matrix metalloproteinase-2 (MMP-2, and MMP-9 mRNA upon kefir treatment were then analyzed using reverse transcriptase polymerase chain reaction (RT-PCR. Finally, the growth inhibitory effects of kefir on cell-cycle progression/apoptosis were assessed by Cell Death Detection (ELISA and flow cytometry.Results: The maximum cytotoxicity recorded after 48-hours treatment with 80 µg/µL kefir was only 42% and 39% in CEM and Jurkat cells, respectively. The percent reduction in proliferation was very significant, and was dose-, and time-dependent. In both cell lines, kefir exhibited its antiproliferative effect by downregulating TGF-α and upregulating TGF- β1 mRNA expression. Upon kefir treatment, a marked increase in cell-cycle distribution was noted in the preG1 phase of CEM and Jurkat cells, indicating the proapoptotic effect of kefir, which was

Development and characterization of a soymilk Kefir-based functional beverage

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Camilla Fernanda Godinho da SILVA

2018-03-01

Full Text Available Abstract Kefir is a fermented beverage that deserves special attention, since it has probiotic activity and unique sensory, nutritional, and therapeutic properties. Given that both kefir and soymilk are beneficial to human health, this study aimed to assess the physicochemical characteristics and acceptability of soymilk Kefir-based functional beverages (SKB properly inoculated with lactobacilli strain after 16h of incubation at 37 °C. It was monitored lactobacilli cell viability, yeasts count, pH, titratable acidity, lipids, proteins, ash, total solid, carbohydrates, caloric values and acceptability of the products. Additionally was conducted a shelf-life study of SKB added of peach-flavor. The lactobacilli cell count ranged from 7.0 to 8.0 Log10 CFUmL-1 and pH values from 4.5 to 4.6. SKB samples with higher soymilk kefir percent presented higher lactobacilli cell count and lower lipid, ash, total solid, carbohydrate and caloric value. Results showed similar preferential rates for the SKB up to 30% of added soymilk kefir. The functional peach-flavored beverage presented appropriate pH value (4.3 and high viable cells count (7.0 Log10 CFUmL-1 up to the 28th day of cold storage, showed high acceptability (94.5% and positive purchase intention (83.4% among consumers.

Characterization of pomegranate juice and whey based novel beverage fermented by kefir grains.

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Sabokbar, Nayereh; Khodaiyan, Faramarz

2015-06-01

Mixture of pomegranate juice and whey was evaluated as a potential substrate for production of a novel probiotic beverage by kefir grains. Different fermentation conditions were used as viz: two fermentation temperature (19 ºC and 25 ºC) and two levels of kefir grains inoculum (5 % and 8%w/v). pH, acidity, lactose consumption as well as organic acids formation were determined during 32 hours of fermentation. Results showed that kefir grains were able to utilize lactose and decrease pH, increase acidity, produce lactic acid and acetic acid, while the level of citric acid decreased. It was observed these change depended on temperature and level of kefir grains with the highest changes at the temperature of 25 ºC and kefir grains inoculum of 8%w/v. Pomegranate juice and whey mixture therefore may serve as a suitable substrate for the production of novel probiotic dairy-fruit juice beverage by kefir grains and the sensory characteristics of this beverage were shown desirable results.

Effects of kefir as a probiotic source on the performance of goat kids ...

African Journals Online (AJOL)

The aim of this study was to investigate the effect of kefir as a probiotic on the performance of goat kids during the pre- (45 days) and post-weaning (45 days) periods. Forty eight kids were randomly allocated to four treatment groups: Control, Kefir, Auto-Kefir (autoclaved) and Probiotic (a commercial probiotic). The kids were ...

Microbiological study of lactic acid bacteria in kefir grains by culture-dependent and culture-independent methods.

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Chen, Hsi-Chia; Wang, Sheng-Yao; Chen, Ming-Ju

2008-05-01

Lactic acid bacteria (LAB) in different original kefir grains were first assessed using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) by a culture-dependent way, and were further confirmed by DNA sequencing techniques. Results indicated that a combined method of cultivation with PCR-DGGE and subsequent DNA sequencing could successfully identify four LAB strains from three kefir grains from Taiwan (named Hsinchu, Mongolia and Ilan). Lactobacillus kefiri accounted, in the three kefir grains, for at least half of the isolated colonies while Lb. kefiranofaciens was the second most frequently isolated species. Leuconostoc mesenteroides was less frequently found but still in the three kefir grains conversely to Lactococcus lactis which based on culture-dependent isolation was only found in two of the kefir grains. It was interesting to find that all three kefir grains contain similar LAB species. Furthermore, the DGGE as a culture-independent method was also applied to detect the LAB strains. Results indicated that Lb. kefiranofaciens was found in all three kefir grains, whereas Lb. kefiri was only observed in Hsinchu kefir grain and Lc. lactis was found in both Mongolia and Ilan samples. Two additional strains, Pseudomonas spp. and E. coli, were also detected in kefir grains.

Pengaruh Jenis Susu dan Persentase Starter yang Berbeda terhadap Kualitas Kefir

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Yusdar Zakaria

2009-04-01

Full Text Available Effect of different milk and starter percentage on kefir quality ABSTRACT. The objective of this study is to study the quality of kefir with different amount of starter added and different kind of milk. The quality of kefir was evaluated by measuring lactic acid level, syneresis, crude protein, crude fat and amount of active microorganism. The result showed that the different percentage of starter and kind of milk has a high significant on syneresis and Lactic Acid level (P < 0,01. The best interaction was resulted from the combination of 10% starter and UHT milk. The result also indicated that the different percentage of starter and kind of milk has no effect on crude protein, crude fat and the amount of active microorganism. The combination of 10% Starter and UHT milk, produces the best quality of kefir

[The effect of kefir consumption on human immune system: a cytokine study].

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Adiloğlu, Ali Kudret; Gönülateş, Nurettin; Işler, Mehmet; Senol, Altuğ

2013-04-01

The systemic effects of bioactive peptides which are produced by the fermentation of milk via the microorganisms found in kefir have been the subject of interest in recent years. Bioactive peptides activate innate immunity by stimulating macrophages, increasing phagocytosis, augmenting NO and cytokine production and boosting the lumen levels of IgG and IgA+ B-lymphocytes. The aim of the present study was to determine the serum cytokine profiles of healthy volunteers after kefir consumption to evaluate helper T (TH) cell polarization and to bring out the effects on native and allergic immune responses. The study was designed as a prospective and self-controlled study. A total of 18 healthy volunteers (age range: 20-40 yrs, mean age: 35.5 ± 7.38 yrs) from a university hospital staff were recruited to the study, with the approval of ethical board and informed consent. The body mass indices of all participants were between normal range (20.10-25.70 kg/m2). After two weeks of a diet free from fermented products, the participants consumed 200 mL kefir daily, for six weeks. Kefir product was prepared by using kefir starter culture (Danisco Biolacta Sp - 05223B 10001, Poland) which contains Lactobacillus spp., Leuconostoc spp., Lactococcus lactis ssp. lactis and Streptococcus termophilus, an overnight incubation at 26°C, and consumed freshly. Fasting blood samples of subjects were collected just before kefir use (0th week), at the end of the 3rd and 6th weeks of kefir consumption, and three weeks after cessation of kefir usage (9th week). Serum TNF-a, IL-1, IL-5, IL-8 and TGF-β levels were measured by using commercial ELISA kits (BioSource, Belgium and Invitrogen, USA). Hemoglobin, serum creatinine and ALT levels of all subjects were also determined for follow-up. All volunteers completed the study period without any problem and declared no complaint. Hemoglobin, creatinine and ALT levels did not change with kefir consumption. Serum IL-8 levels were decreased at 3rd and

Kefir improves bone mass and microarchitecture in an ovariectomized rat model of postmenopausal osteoporosis.

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Chen, H-L; Tung, Y-T; Chuang, C-H; Tu, M-Y; Tsai, T-C; Chang, S-Y; Chen, C-M

2015-02-01

Kefir treatment in ovariectomized (OVX) rats could significantly decrease the levels of bone turnover markers and prevent OVX-induced bone loss, deterioration of trabecular microarchitecture, and biomechanical dysfunction that may be due to increase intracellular calcium uptake through the TRPV6 calcium channel. Osteoporosis is a disease characterized by low bone mass and structural deterioration of bone tissue, leading to an increased fracture risk. The incidence of osteoporosis increases with age and occurs most frequently in postmenopausal women due to estrogen deficiency, as the balance between bone resorption and bone formation shifts towards increased levels of bone resorption. Among various methods of prevention and treatment for osteoporosis, an increase in calcium intake is the most commonly recommended preventive measure. Kefir is a fermented milk product made with kefir grains that degrade milk proteins into various peptides with health-promoting effects, including immunomodulating-, antithrombotic-, antimicrobial-, and calcium-absorption-enhancing bioactivities. The aim of this study is to investigate the effect of kefir on osteoporosis prophylaxis in an ovariectomized rat model. A total of 56 16-week-old female Sprague-Dawley (SD) rats were divided into 7 experimental groups: sham (normal), OVX/Mock, OVX/1X kefir (164 mg/kg BW/day), OVX/2X kefir (328 mg/kg BW/day), OVX/4X kefir (656 mg/kg BW/day), OVX/ALN (2.5 mg/kg BW/day), and OVX/REBONE (800 mg/kg BW/day). After 12-week treatment with kefir, the bone physiology in the OVX rat model was investigated. Accordingly, the aim of this study was to investigate the possible transport mechanism involved in calcium absorption using the Caco-2 human cell line. A 12-week treatment with kefir on the OVX-induced osteoporosis model reduced the levels of C-terminal telopeptides of type I collagen (CTx), bone turnover markers, and trabecular separation (Tb. Sp.). Additionally, treatment with kefir increased

Chronic administration of the probiotic kefir improves the endothelial function in spontaneously hypertensive rats.

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Friques, Andreia G F; Arpini, Clarisse M; Kalil, Ieda C; Gava, Agata L; Leal, Marcos A; Porto, Marcella L; Nogueira, Breno V; Dias, Ananda T; Andrade, Tadeu U; Pereira, Thiago Melo C; Meyrelles, Silvana S; Campagnaro, Bianca P; Vasquez, Elisardo C

2015-12-30

The beverage obtained by fermentation of milk with kefir grains, a complex matrix containing acid bacteria and yeasts, has been shown to have beneficial effects in various diseases. However, its effects on hypertension and endothelial dysfunction are not yet clear. In this study, we evaluated the effects of kefir on endothelial cells and vascular responsiveness in spontaneously hypertensive rats (SHR). SHR were treated with kefir (0.3 mL/100 g body weight) for 7, 15, 30 and 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Vascular endothelial function was evaluated in aortic rings through the relaxation response to acetylcholine (ACh). The balance between reactive oxygen species (ROS) and nitric oxide (NO) synthase was evaluated through specific blockers in the ACh-induced responses and through flow cytometry in vascular tissue. Significant effects of kefir were observed only after treatment for 60 days. The high blood pressure and tachycardia exhibited by the SHR were attenuated by approximately 15 % in the SHR-kefir group. The impaired ACh-induced relaxation of the aortic rings observed in the SHR (37 ± 4 %, compared to the Wistar rats: 74 ± 5 %), was significantly attenuated in the SHR group chronically treated with kefir (52 ± 4 %). The difference in the area under the curve between before and after the NADPH oxidase blockade or NO synthase blockade of aortic rings from SHR were of approximately +90 and -60 %, respectively, when compared with Wistar rats. In the aortic rings from the SHR-kefir group, these values were reduced to +50 and -40 %, respectively. Flow cytometric analysis of aortic endothelial cells revealed increased ROS production and decreased NO bioavailability in the SHR, which were significantly attenuated by the treatment with kefir. Scanning electronic microscopy showed vascular endothelial surface injury in SHR, which was partially protected following administration of kefir for 60 days. In addition, the

Administration of probiotic kefir to mice with Clostridium difficile infection exacerbates disease.

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Spinler, Jennifer K; Brown, Aaron; Ross, Caná L; Boonma, Prapaporn; Conner, Margaret E; Savidge, Tor C

2016-08-01

Lifeway(®) kefir, a fermented milk product containing 12 probiotic organisms, is reported to show promise as an alternative to fecal microbiota transplantation for recurrent Clostridium difficile infection (CDI). We employed a murine CDI model to study the probiotic protective mechanisms and unexpectedly determined that kefir drastically increased disease severity. Our results emphasize the need for further independent clinical testing of kefir as alternative therapy in recurrent CDI. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microbial Succession and Flavor Production in the Fermented Dairy Beverage Kefir.

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Walsh, Aaron M; Crispie, Fiona; Kilcawley, Kieran; O'Sullivan, Orla; O'Sullivan, Maurice G; Claesson, Marcus J; Cotter, Paul D

2016-01-01

Kefir is a putatively health-promoting dairy beverage that is produced when a kefir grain, consisting of a consortium of microorganisms, is added to milk to initiate a natural fermentation. Here, a detailed analysis was carried out to determine how the microbial population, gene content, and flavor of three kefirs from distinct geographic locations change over the course of 24-h fermentations. Metagenomic sequencing revealed that Lactobacillus kefiranofaciens was the dominant bacterial species in kefir during early stages of fermentations but that Leuconostoc mesenteroides became more prevalent in later stages. This pattern is consistent with an observation that genes involved in aromatic amino acid biosynthesis were absent from L. kefiranofaciens but were present in L. mesenteroides . Additionally, these shifts in the microbial community structure, and associated pathways, corresponded to changes in the levels of volatile compounds. Specifically, Acetobacter spp. correlated with acetic acid; Lactobacillus spp. correlated with carboxylic acids, esters and ketones; Leuconostoc spp. correlated with acetic acid and 2,3-butanedione; and Saccharomyces spp. correlated with esters. The correlation data suggest a causal relationship between microbial taxa and flavor that is supported by observations that addition of L. kefiranofaciens NCFB 2797 increased the levels of esters and ketones whereas addition of L. mesenteroides 213M0 increased the levels of acetic acid and 2,3-butanedione. Finally, we detected genes associated with probiotic functionalities in the kefir microbiome. Our results illustrate the dynamic nature of kefir fermentations and microbial succession patterns therein and can be applied to optimize the fermentation processes, flavors, and health-related attributes of this and other fermented foods. IMPORTANCE Traditional fermented foods represent relatively low-complexity microbial environments that can be used as model microbial communities to understand

Comparative in vitro efficacy of kefir produced from camel, goat, ewe and cow milk on Haemonchus contortus.

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Alimi, D; Rekik, M; Akkari, H

2018-04-18

One of the great challenges of veterinary parasitology is the search for alternative methods for controlling gastrointestinal parasites in small ruminants. Milk kefir is a traditional source of probiotic, with great therapeutic potential. The objective of this study was to investigate the anthelmintic effects of kefir on the abomasal nematode Haemonchus contortus from sheep. The study used camel, goat, ewe and cow milk as a starting material, to produce camel, goat, cow and ewe milk kefir. All kefirs showed a significant concentration-dependent effect on H. contortus egg hatching at all tested concentrations. The highest inhibition (100%) of eggs was observed with camel milk kefir at a concentration 0.125 mg/ml. In relation to the effect of kefirs on the survival of adult parasites, all kefirs induced concentration-dependent mortality in adults, with variable results. The complete mortality (100%) of adults of H. contortus occurred at concentrations in the range 0.25-2 mg/ml. The highest inhibition of motility (100%) of worms was observed after 8 h post exposure with camel milk kefir at 0.25 mg/ml. These findings indicate that kefir can be considered a potential tool to control haemonchosis in sheep. Further investigations are needed to assess the active molecules in kefir responsible for its anthelmintic properties and to investigate similar in vivo effects.

AVALIAÇÃO DA ADIÇÃO DO KEFIR EM DIETA HOSPITALAR

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Joice de Fátima Laureano Martins

2012-06-01

Full Text Available Os grãos de kefir são utilizados na elaboração de um produto lácteo fermentado o qual denominamos kefir. Sua introdução em dietas hospitalares promove vários benefícios aos pacientes e possui grande capacidade de estimular o sistema imunológico. Objetivou-se verificar a aceitação de diferentes formulações tendo como ingrediente o kefir. Os grãos de kefir (5 % foram cultivados por 24 horas à temperatura de 22º C. Em seguida, foram preparadas quatro formulações. Formulação 1 - 50 % de kefir cultivado em leite de vaca integral com 50 % de polpa de morango e adoçante (0,2 mL/100 mL; formulação 2 - 50 % de kefir cultivado em leite de vaca desnatado com 50 % de polpa de morango e adoçante (0,2 mL/100 mL; formulação 3 - 50 % de kefir cultivado em leite de vaca integral com 50 % de polpa de morango e 10 % de sacarose e formulação 4 - 50 % de kefir cultivado em leite de vaca desnatado com 50 % de polpa de morango e 10 % de sacarose. A análise sensorial foi realizada em um hospital do município de Viçosa-MG, tendo como provadores acompanhantes de pacientes internados e funcionários. Verificou-se a aceitação das formulações e utilizouse a escala hedônica de nove pontos. Todas as formulações apresentaram considerável aceitação enquadrando-se com maior frequência entre os escores «gostei moderadamente» a «gostei muito». Estes formulados apresentaram grande potencial para serem introduzidos em dietoterapia e poderão atuar tanto como adjunto ao tratamento de patologias gastrintestinais, como no controle glicêmico e hipercolesterolêmico.

Kefir: composition and evaluation of in situ antagonistic activity against Staphylococcus aureus and Escherichia coli.

Directory of Open Access Journals (Sweden)

Simone Weschenfelder

Full Text Available ABSTRACT The aim of this study was to investigate whether produced kefir meets the identity and quality standards for fermented milks, to check the possibility of assigning a nutrition declaration, and to evaluate the antagonistic activity of the fermented milk against Staphylococcus aureus and Escherichia coli. Two different formulations of kefir (Kefir 1 and Kefir 2 were prepared to determine the percentage composition, minerals, pH, total lactic acid bacteria, and antagonistic activity against Staphylococcus aureus and Escherichia coli. The results of the physicochemical evaluation indicated a statistically significant difference between the formulations, except for the percentage of lipids, Ca, K, Mg and Na. The formulations met the parameters of identity and quality in the fermented milks under evaluation. Possible nutrition declarations for Kefir 1 are 'source of proteins' and 'reduced calorie', and for Kefir 2, 'high protein content' and 'high zinc content'. The fermented milks showed significant antagonistic activity against the tested microorganisms (> 24 h, with no activity seen after this period. Further studies involving kefir are suggested, exploring its potential as a probiotic food, and its inclusion in the diet of the population.

Antidiabetic Potential of Kefir Combination from Goat Milk and Soy Milk in Rats Induced with Streptozotocin-Nicotinamide.

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Nurliyani; Harmayani, Eni; Sunarti

2015-01-01

The study aimed to evaluate the effect of kefir combination from goat milk and soy milk on lipid profile, plasma glucose, glutathione peroxidase (GPx) activity and the improvement of pancreatic β-cell in diabetic rats. Male rats were divided into five treatments: normal control, diabetic control, goat milk kefir, combination of goat milk-soy milk kefir and soy milk kefir. All rats were induced by streptooztocin-nicotinamide (STZ-NA), except for normal control. After 35 d experiment, the rats were sampled for blood, sacrificed and sampled for pancreatic tissues. Results showed that diabetic rats fed kefir combination had higher (pkefir. Decreasing of plasma glucose in diabetic rats fed kefir combination was higher (pkefir. The activity of GPx in diabetic rats fed three kinds of kefir were higher (pkefir combination was the same as the normal control, but it was higher than diabetic control. It was concluded that kefir combination can be used as antidiabetic through maintaining in serum triglyceride, decreasing in plasma glucose, increasing in GPx activity and improving in pancreatic β-cells.

Sequence-based analysis of the microbial composition of water kefir from multiple sources.

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Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D

2013-11-01

Water kefir is a water-sucrose-based beverage, fermented by a symbiosis of bacteria and yeast to produce a final product that is lightly carbonated, acidic and that has a low alcohol percentage. The microorganisms present in water kefir are introduced via water kefir grains, which consist of a polysaccharide matrix in which the microorganisms are embedded. We aimed to provide a comprehensive sequencing-based analysis of the bacterial population of water kefir beverages and grains, while providing an initial insight into the corresponding fungal population. To facilitate this objective, four water kefirs were sourced from the UK, Canada and the United States. Culture-independent, high-throughput, sequencing-based analyses revealed that the bacterial fraction of each water kefir and grain was dominated by Zymomonas, an ethanol-producing bacterium, which has not previously been detected at such a scale. The other genera detected were representatives of the lactic acid bacteria and acetic acid bacteria. Our analysis of the fungal component established that it was comprised of the genera Dekkera, Hanseniaspora, Saccharomyces, Zygosaccharomyces, Torulaspora and Lachancea. This information will assist in the ultimate identification of the microorganisms responsible for the potentially health-promoting attributes of these beverages. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

Effects of Kefir on the Cardiac Autonomic Tones and Baroreflex Sensitivity in Spontaneously Hypertensive Rats.

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Klippel, Brunella F; Duemke, Licia B; Leal, Marcos A; Friques, Andreia G F; Dantas, Eduardo M; Dalvi, Rodolfo F; Gava, Agata L; Pereira, Thiago M C; Andrade, Tadeu U; Meyrelles, Silvana S; Campagnaro, Bianca P; Vasquez, Elisardo C

2016-01-01

It has been previously shown that the probiotic kefir (a symbiotic matrix containing acid bacteria and yeasts) attenuated the hypertension and the endothelial dysfunction in spontaneously hypertensive rats (SHR). In the present study, the effect of chronic administration of kefir on the cardiac autonomic control of heart rate (HR) and baroreflex sensitivity (BRS) in SHR was evaluated. SHR were treated with kefir (0.3 mL/100 g body weight) for 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Cardiac autonomic vagal (VT) and sympathetic (ST) tones were estimated through the blockade of the cardiac muscarinic receptors (methylatropine) and the blockade of β1-adrenoceptor (atenolol). The BRS was evaluated by the tachycardia and bradycardia responses to vasoactive drug-induced decreases and increases in arterial blood pressure (BP), respectively. Additionally, spontaneous BRS was estimated by autoregressive spectral analysis. Kefir-treated SHR exhibited significant attenuation of basal BP, HR, and cardiac hypertrophy compared to non-treated SHR (12, 13, and 21%, respectively). Cardiac VT and ST were significantly altered in the SHR (~40 and ~90 bpm) compared with Wistar rats (~120 and ~30 bpm) and were partially recovered in SHR-kefir (~90 and ~25 bpm). SHR exhibited an impaired bradycardic BRS (~50%) compared with Wistar rats, which was reduced to ~40% in the kefir-treated SHR and abolished by methylatropine in all groups. SHR also exhibited a significant impairment of the tachycardic BRS (~23%) compared with Wistar rats and this difference was reduced to 8% in the SHR-kefir. Under the action of atenolol the residual reflex tachycardia was smaller in SHR than in Wistar rats and kefir attenuated this abnormality. Spectral analysis revealed increased low frequency components of BP (~3.5-fold) and pulse interval (~2-fold) compared with Wistar rats and these differences were reduced by kefir-treatment to ~1.6- and ~1.5-fold, respectively

Effects of Kefir on the Cardiac Autonomic Tones and Baroreflex Sensitivity in Spontaneously Hypertensive Rats

Science.gov (United States)

Klippel, Brunella F.; Duemke, Licia B.; Leal, Marcos A.; Friques, Andreia G. F.; Dantas, Eduardo M.; Dalvi, Rodolfo F.; Gava, Agata L.; Pereira, Thiago M. C.; Andrade, Tadeu U.; Meyrelles, Silvana S.; Campagnaro, Bianca P.; Vasquez, Elisardo C.

2016-01-01

Aims: It has been previously shown that the probiotic kefir (a symbiotic matrix containing acid bacteria and yeasts) attenuated the hypertension and the endothelial dysfunction in spontaneously hypertensive rats (SHR). In the present study, the effect of chronic administration of kefir on the cardiac autonomic control of heart rate (HR) and baroreflex sensitivity (BRS) in SHR was evaluated. Methods: SHR were treated with kefir (0.3 mL/100 g body weight) for 60 days and compared with non-treated SHR and with normotensive Wistar-Kyoto rats. Cardiac autonomic vagal (VT) and sympathetic (ST) tones were estimated through the blockade of the cardiac muscarinic receptors (methylatropine) and the blockade of β1−adrenoceptor (atenolol). The BRS was evaluated by the tachycardia and bradycardia responses to vasoactive drug-induced decreases and increases in arterial blood pressure (BP), respectively. Additionally, spontaneous BRS was estimated by autoregressive spectral analysis. Results: Kefir-treated SHR exhibited significant attenuation of basal BP, HR, and cardiac hypertrophy compared to non-treated SHR (12, 13, and 21%, respectively). Cardiac VT and ST were significantly altered in the SHR (~40 and ~90 bpm) compared with Wistar rats (~120 and ~30 bpm) and were partially recovered in SHR-kefir (~90 and ~25 bpm). SHR exhibited an impaired bradycardic BRS (~50%) compared with Wistar rats, which was reduced to ~40% in the kefir-treated SHR and abolished by methylatropine in all groups. SHR also exhibited a significant impairment of the tachycardic BRS (~23%) compared with Wistar rats and this difference was reduced to 8% in the SHR-kefir. Under the action of atenolol the residual reflex tachycardia was smaller in SHR than in Wistar rats and kefir attenuated this abnormality. Spectral analysis revealed increased low frequency components of BP (~3.5-fold) and pulse interval (~2-fold) compared with Wistar rats and these differences were reduced by kefir-treatment to ~1

Removal of cadmium by Lactobacillus kefir as a protective tool against toxicity.

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Gerbino, Esteban; Carasi, Paula; Tymczyszyn, E Elizabeth; Gómez-Zavaglia, Andrea

2014-08-01

The aim of this work was to evaluate the capacity of Lactobacillus kefir strains to remove cadmium cations and protect eukaryotic cells from cadmium toxicity. Lb. kefir CIDCA 8348 and JCM 5818 were grown in a 1/2 dilution of MRS broth supplemented with Cd(NO3)2 ranging 0 to 1 mM. Growth kinetics were followed during 76 h at 30 °C by registering optical density at 600 nm every 4-10 h. The accumulated concentration of cadmium was determined on cultures in the stationary phase by atomic absorption. The viability of a human hepatoma cell line (HepG2) upon exposure to (a) free cadmium and (b) cadmium previously incubated with Lb. kefir strains was evaluated by determining the mitochondrial dehydrogenase activity. Lb. kefir strains were able to grow and tolerate concentrations of cadmium cations up to 1 mM. The addition of cadmium to the culture medium increased the lag time in all the concentrations used. However, a decrease of the total biomass (maximum Absorbance) was observed only at concentrations above 0.0012 and 0.0011 mM for strains CIDCA 8348 and JCM 5818, respectively. Shorter and rounder lactobacilli were observed in both strains upon microscopic observations. Moreover, dark precipitates compatible with intracellular precipitation of cadmium were observed in the cytoplasm of both strains. The ability of Lb. kefir to protect eukaryotic cells cultures from cadmium toxicity was analysed using HepG2 cells lines. Concentrations of cadmium greater than 3×10(-3) mM strongly decreased the viability of HepG2 cells. However, when the eukaryotic cells were exposed to cadmium pre-incubated 1 h with Lb. kefir the toxicity of cadmium was considerably lower, Lb. kefir JCM 5818 being more efficient. The high tolerance and binding capacity of Lb. kefir strains to cadmium concentrations largely exceeding the tolerated weekly intake (TWI) of cadmium for food (2.5 μg per kg of body weight) and water (3 μg/l) addressed to human consumption, is an important added value when

Anti–odor activity of milk kefir on organosulphur polysulfide cyclic compounds in petai (parkia speciosa hassk)

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Kurniati, T.; Windayani, N.; Listiawati, M.

2018-05-01

This study aims to assess the activity of milk kefir whey in neutralizing odor-causing cyclic polysulfide compounds in petai (Parkia speciosa Hassk.). RAL designs used to determine the optimum fermentation conditions. The data obtained were processed using SPSS 20. Results showed the characteristics of the microbes in the kefir grains include lactic acid bacteria consisting of genus Lactobacillus and yeast of the genus Candida and Saccharomyces. The optimum fermentation conditions using cow’s milk kefir grain starter obtained in the fermentation time of 24 hours at a concentration of 5% kefir grain. Whey kefir which is produced have high levels of fat, protein, carbohydrates, fiber and lactic acid respectively 1.81; 4.35; 5.59; 0.26 and 0.16%, pH 4.4; a density of 1.0628 g/mL and 7.9368 cP viscosity. Kefir milk whey actively reduced the level of petai smell significantly different at the level of α = 0.05.

Kefir Mikroflorası Üzerinde Araştırma

OpenAIRE

Erol Ergüllü; Mustafa Üçüncü

2015-01-01

Çalışmada, çeşitli yörelerden sağlanmış 7 kefir örneğinin mikroflorası araştırılmış ve elde edilen bulgulara göre, kefir mikroflorasında süt asidi bakterileri (Streptokok ve Laktobasiller) ile mayaların çoğunlukta olduğu belirlenmiştir. Bu bakteri türlerinden her birinin kefir oluşumunda ayrı bir yeri bulunmaktadır. Süt asidi bakterileri sütü pıhtılaştırmakta ve bunlardan bazıları da ayrıca uçucu asitler oluşturarak, kefirin tat ve kokusunun meydana gelmesine katkıda bulunmaktadırlar. Mayalar...

Kefir Mikroflorası Üzerinde Araştırma

OpenAIRE

Ergüllü, Erol; Üçüncü, Mustafa

2014-01-01

  Çalışmada, çeşitli yörelerden sağlanmış 7 kefir örneğinin mikroflorası araştırılmış ve elde edilen bulgulara göre, kefir mikroflorasında süt asidi bakterileri (Streptokok ve Laktobasiller) ile mayaların çoğunlukta olduğu belirlenmiştir. Bu bakteri türlerinden her birinin kefir oluşumunda ayrı bir yeri bulunmaktadır. Süt asidi bakterileri sütü pıhtılaştırmakta ve bunlardan bazıları da ayrıca uçucu asitler oluşturarak, kefirin tat ve kokusunun meydana gelmesine katkıda bulunmaktadırlar. Mayal...

Kefir Mikroflorası Üzerinde Araştırma

OpenAIRE

Ergüllü, Erol; Üçüncü, Mustafa

2015-01-01

  Çalışmada, çeşitli yörelerden sağlanmış 7 kefir örneğinin mikroflorası araştırılmış ve elde edilen bulgulara göre, kefir mikroflorasında süt asidi bakterileri (Streptokok ve Laktobasiller) ile mayaların çoğunlukta olduğu belirlenmiştir. Bu bakteri türlerinden her birinin kefir oluşumunda ayrı bir yeri bulunmaktadır. Süt asidi bakterileri sütü pıhtılaştırmakta ve bunlardan bazıları da ayrıca uçucu asitler oluşturarak, kefirin tat ve kokusunun meydana gelmesine katkıda bulunmaktadırlar. Mayal...

Chronic administration of the soluble, nonbacterial fraction of kefir attenuates lipid deposition in LDLr-/- mice.

Science.gov (United States)

Santanna, Adriélly F; Filete, Placielle F; Lima, Ewelyne M; Porto, Marcella L; Meyrelles, Silvana S; Vasquez, Elisardo C; Endringer, Denise C; Lenz, Dominik; Abdalla, Dulcineia S P; Pereira, Thiago M C; Andrade, Tadeu U

2017-03-01

Kefir is obtained by the action of acidic bacteria and yeasts that exist in symbiotic association in kefir grains. Recently, this fermented milk drink has been recommended for the treatment of several clinical conditions, such as inflammatory, gastrointestinal, or cardiovascular-related diseases, or a combination of these diseases. However, its effects on atherosclerosis are not yet clear. The aim of this study was to prove that chronic treatment with a soluble, nonbacterial fraction of kefir could reduce the progression of atherosclerosis in low-density lipoprotein receptor-deficient (LDLr -/- ) mice. LDLr -/- mice were divided into four groups as follows: RESULTS: The soluble, nonbacterial fraction of kefir reduced lipid deposition (P < 0.05) independent of hypercholesterolemia. Moreover, kefir was capable of diminishing the circulating proinflammatory intereukin (IL)-6 level and the ratio of tumor necrosis factor-α to IL-10 (50% and 42%, P < 0.05, respectively) and augmenting the antiinflammatory IL-10 level by approximately 74% (P < 0.05). Chronic treatment with a soluble nonbacterial fraction of kefir was able to decrease the lipid deposition in LDLr -/- hypercholesteremic mice, at least in part through modifying the circulating cytokine profile. The beneficial effects of kefir provide new perspectives for its use as an adjuvant in the prevention of atherosclerosis. Copyright © 2016 Elsevier Inc. All rights reserved.

Kefir protective effects against nicotine cessation-induced anxiety and cognition impairments in rats.

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Noori, Negin; Bangash, Mohammad Yasan; Motaghinejad, Majid; Hosseini, Pantea; Noudoost, Behshad

2014-01-01

Nicotine as one of the potent psychostimulant drugs is characterized by its parasympathomimetic activity. Upon the abrupt discontinuation of nicotine intake, a number of symptoms such as anxiety, depression and cognition impairment develop. Kefir as a food supplement is rich in tryptophan. In this study, we have evaluated the effects of Kefir on nicotine cessation-induced anxiety, depression and cognition impairment. Forty adult male rats were divided into four groups. All the groups received 6 mg/kg/day of nicotine for 17 days and then the negative control groups got 5 mg/kg/day of normal saline. The positive control groups were given 40 mg/kg/day of Sertraline HCl for 7 days. The group treated with Cow Milk Kefir (CMK) and Soy Milk Kefir (SMK) received 5 mg/kg/day for 7 days. On the 25(th) day, Elevated Plus Maze (EPM), Open Field Test (OFT) and Forced Swim Test (FST) were used to investigate anxiety and depression. In addition, Moris Water Maze was applied to evaluate learning and memory in the animals between the 20(th) and 25(th) days. The results showed that administration of CMK, SMK and Sertraline had higher anti-depression and anxiolytic effects on nicotine withdrawal-induced depression and anxiety in rats (P Kefir had a potential effect on the treatment of nicotine cessation-induced depression, anxiety and cognition impairment in the animal model. Kefir may be useful for adjunct therapy for nicotine abandonment treatment protocols.

Selection of lactic acid bacteria from Brazilian kefir grains for potential use as starter or probiotic cultures.

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Zanirati, Débora Ferreira; Abatemarco, Mário; Sandes, Sávio Henrique de Cicco; Nicoli, Jacques Robert; Nunes, Álvaro Cantini; Neumann, Elisabeth

2015-04-01

Brazilian kefir is a homemade fermented beverage that is obtained by incubating milk or a brown sugar solution with kefir grains that contribute their different microbiological compositions. It is highly important to isolate and characterize microorganisms from Brazilian kefir grains to obtain starter cultures for the industrial production of a standardized commercial kefir. Thus, the present study aimed to isolate lactic acid bacteria from eight kefir grains that were propagated in milk or sugar solutions from five different locations in Brazil and to select Lactobacillus isolates based on desirable in vitro probiotic properties. One hundred eight isolates from both substrates were identified by amplified ribosomal DNA restriction analysis and/or 16S rRNA gene sequencing and were determined to belong to the following 11 species from the genera: Lactococcus, Leuconostoc, Lactobacillus (L.), and Oenococcus. Leuconostoc mesenteroides, Lactobacillus kefiri, and Lactobacillus kefiranofaciens were isolated only from milk grains, whereas Lactobacillus perolens, Lactobacillus parafarraginis, Lactobacillus diolivorans, and Oenococcus oeni were isolated exclusively from sugar water grains. When the microbial compositions of four kefir grains were evaluated with culture-independent analyses, L. kefiranofaciens was observed to predominant in milk grains, whereas Lactobacillus hilgardii was most abundant in sugar water kefir. Unfortunately, L. hilgardii was not isolated from any grain, although this bacteria was detected with a culture-independent methodology. Fifty-two isolated Lactobacilli were tested for gastric juice and bile salt tolerance, antagonism against pathogens, antimicrobial resistance, and surface hydrophobicity. Three Lactobacillus strains (L. kefiranofaciens 8U, L. diolivorans 1Z, and Lactobacillus casei 17U) could be classified as potential probiotics. In conclusion, several lactic acid bacteria that could be used in combination with yeasts as starter

Kefir protective effects against nicotine cessation-induced anxiety and cognition impairments in rats

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Negin Noori

2014-01-01

Conclusion: This study revealed that Kefir had a potential effect on the treatment of nicotine cessation-induced depression, anxiety and cognition impairment in the animal model. Kefir may be useful for adjunct therapy for nicotine abandonment treatment protocols.

Sequencing-based analysis of the bacterial and fungal composition of kefir grains and milks from multiple sources.

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Alan J Marsh

Full Text Available Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists.

Sequencing-Based Analysis of the Bacterial and Fungal Composition of Kefir Grains and Milks from Multiple Sources

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Marsh, Alan J.; O’Sullivan, Orla; Hill, Colin; Ross, R. Paul; Cotter, Paul D.

2013-01-01

Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists. PMID:23894461

Sequencing-based analysis of the bacterial and fungal composition of kefir grains and milks from multiple sources.

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Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D

2013-01-01

Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists.

Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells.

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Yamane, Takuya; Sakamoto, Tatsuji; Nakagaki, Takenori; Nakano, Yoshihisa

2018-03-27

The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis , Lactococcus . lactis subsp. Cremoris , Lactococcus. Lactis subsp. Lactis biovar diacetylactis , Lactobacillus plantarum , Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei . In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma) increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity.

The protective effects of fermented kefir milk on azoxymethane-induced aberrant crypt formation in mice colon.

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Melo, Aline Freitas de Paula; Mendonça, Monique Culturato Padilha; Rosa-Castro, Raquel de Mendonça

2018-06-01

Kefir is a probiotic fermented milk product produced from grains with a complex composition of bacteria and yeasts that live in a symbiotic association. Anti-proliferative, anti-inflammatory, and anti-mutagenic effects are some of the health beneficial properties of kefir grains. The present study was conducted to evaluate whether regular consumption of kefir milk would be capable of preventing the development of pre-neoplastic lesions induced by azoxymethane (AOM). Aberrant crypt foci were induced in BALB-c mice via 2 subcutaneous injections of azoxymethane (15 mg/kg) and kefir was administered by daily gavage for 8 weeks (5 ml/kg). Additionally, bacterial growth was monitored in pasteurized and ultra-high temperature (UHT) treated milk to compare different fermentation conditions. Our results showed that UHT milk presented better growth of Lactobacillus acidophilus colonies. The aberrant crypt foci were attenuated by approximately 43% (height) and 20% (width) in the kefir group compared to AOM group, suggesting that kefir treatment may contribute to prevent and control the growth of intestinal neoplastic cells. Copyright © 2018 Elsevier Ltd. All rights reserved.

The protective effect of fermented milk kefir on radiation-induced apoptosis in colonic crypt cells of rats

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Matsuu, Mutsumi; Shichijo, Kazuko; Okaichi, Kumio

2003-01-01

To evaluate the effect of fermented milk kefir on X-ray-induced apoptosis in the colon of rats, we examined the apoptotic index, the mean number of apoptotic cells detected by H and E staining per crypt in the colon, in control rats and kefir-pretreated rats drinking kefir for 12 days before irradiation. Apoptotic cells were confirmed by TUNEL staining, and active caspase-3 expression was studied by immunohistochemistry. The cell position of apoptotic cells and active caspase-3 positive cells were examined. The apoptotic index of kefir-treated rats was significantly (p<0.05) decreased 2 h after 1 Gy irradiation in comparison with control rats at crypt cell positions 1-3, 5-7, 13, and 15. Active caspase-3 expression in the kefir-treated rats was also significantly (p<0.05) reduced in comparison with control rats 2 h after 1 Gy irradiation at crypt cell positions 1-4, 13, and 15. This study indicated that kefir protects colonic crypt cells against radiation-induced apoptosis, which was most pronounced in the stem cell region of the crypt. The antiapoptotic effect of fermented milk kefir was due to the inhibition of caspase-3 activation. (author)

Investigation of the Protective Effect of Kefir against Isoproterenol Induced Myocardial Infarction in Rats

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Mert, Handan; Yılmaz, Hikmet; Irak, Kıvanç; Yıldırım, Serkan; Mert, Nihat

2018-01-01

Abstract This study aims to investigate the protective effects of kefir against myocardial infarction induced by isoproterenol (ISO). The rats were randomly divided into 4 groups, each group consisting of 8 rats. The control group, the kefir group (5 mL/kg/d kefir administered to rats as intra-gastric gavage for 60 d), the ISO group (100 mg/kg ISO was administered to rats, s.c. on 61. and 62. d), and kefir+ISO group (5 mL/kg/d kefir was administered to rats intra gastric gavage for 60 days prior to ISO, 100 mg/kg in two doses on day 61 and 62). 12 h after the last ISO dose, all rats were decapitated and their blood samples were collected. Cardiac tissue was reserved for histopathological examination. creatine kinase (CK), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), triglycerides, total cholesterol,very low density lipoprotein (VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL) and glucose were measured by autoanalyzer, whole blood malondialdehyde (MDA), glutathione (GSH) and plasma advanced oxidation protein products (AOPP) levels were measured spectrophotometrically. It was determined that in the group of kefir+ISO, the levels of AST (pkefir in myocardial infarction induced by ISO can protect the heart with its antioxidant characteristic and minimize the toxic damage created by ISO. PMID:29805276

Caracterização físico-química e sensorial de kefir tradicional e derivados

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S. Weschenfelder

2011-04-01

Full Text Available Avaliaram-se diferentes populações de grãos de kefir tradicional e de seus derivados, o kefir, o kefir leban e o soro de kefir, quanto às características físico-químicas e sensoriais, quando inoculados em diferentes concentrações de leite padronizado, levando-se em consideração as variáveis tempo/temperatura de incubação, maturação e filtração. A manipulação da população de grãos de kefir foi eficaz na obtenção de produtos com características físico-químicas semelhantes. O volume de leite utilizado na incubação influenciou significativamente as características dos derivados. A avaliação sensorial de antepastos elaborados a partir de kefir leban, condimentados, apresentou boa aceitabilidade.

Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells

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Takuya Yamane

2018-03-01

Full Text Available The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis, Lactococcus. lactis subsp. Cremoris, Lactococcus. Lactis subsp. Lactis biovar diacetylactis, Lactobacillus plantarum, Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei. In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity.

Modelling of aflatoxin G1 reduction by kefir grain using response surface methodology.

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Ansari, Farzaneh; Khodaiyan, Faramarz; Rezaei, Karamatollah; Rahmani, Anosheh

2015-01-01

Aflatoxin G1 (AFG1) is one of the main toxic contaminants in pistachio nuts and causes potential health hazards. Hence, AFG1 reduction is one of the main concerns in food safety. Kefir-grains contain symbiotic association of microorganisms well known for their aflatoxin decontamination effects. In this study, a central composite design (CCD) using response surface methodology (RSM) was applied to develop a model in order to predict AFG1 reduction in pistachio nuts by kefir-grain (already heated at 70 and 110°C). The independent variables were: toxin concentration (X1: 5, 10, 15, 20 and 25 ng/g), kefir-grain level (X2: 5, 10, 20, 10 and 25%), contact time (X3: 0, 2, 4, 6 and 8 h), and incubation temperature (X4: 20, 30, 40, 50 and 60°C). There was a significant reduction in AFG1 (p kefir-grain used. The variables including X1, X3 and the interactions between X2-X4 as well as X3-X4 have significant effects on AFG1 reduction. The model provided a good prediction of AFG1 reduction under the assay conditions. Optimization was used to enhance the efficiency of kefir-grain on AFG1 reduction. The optimum conditions for the highest AFG1 reduction (96.8%) were predicted by the model as follows: toxin concentration = 20 ng/g, kefir-grain level = 10%, contact time = 6 h, and incubation temperature = 30°C which validated practically in six replications.

The Neuroprotective Effect of Kefir on Spinal Cord Ischemia/Reperfusion Injury in Rats

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Akman, Tarik; Yener, Ali Umit; Sehitoglu, Muserref Hilal; Yuksel, Yasemin; Cosar, Murat

2015-01-01

Objective The main causes of spinal cord ischemia are a variety of vascular pathologies causing acute arterial occlusions. We investigated neuroprotective effects of kefir on spinal cord ischemia injury in rats. Methods Rats were divided into three groups : 1) sham operated control rats; 2) spinal cord ischemia group fed on a standard diet without kefir pretreatment; and 3) spinal cord ischemia group fed on a standard diet plus kefir. Spinal cord ischemia was performed by the infrarenal aorta cross-clamping model. The spinal cord was removed after the procedure. The biochemical and histopathological changes were observed within the samples. Functional assessment was performed for neurological deficit scores. Results The kefir group was compared with the ischemia group, a significant decrease in malondialdehyde levels was observed (pkefir group were significantly higher than ischemia group (pkefir group is compared with ischemia group, there was a significant decrease in numbers of dead and degenerated neurons (pkefir group compared with ischemia group (pkefir group were significantly higher than ischemia group at 24 h (pkefir pretreatment in spinal cord ischemia/reperfusion reduced oxidative stress and neuronal degeneration as a neuroprotective agent. Ultrastructural studies are required in order for kefir to be developed as a promising therapeutic agent to be utilized for human spinal cord ischemia in the future. PMID:26113960

The Neuroprotective Effect of Kefir on Spinal Cord Ischemia/Reperfusion Injury in Rats.

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Guven, Mustafa; Akman, Tarik; Yener, Ali Umit; Sehitoglu, Muserref Hilal; Yuksel, Yasemin; Cosar, Murat

2015-05-01

The main causes of spinal cord ischemia are a variety of vascular pathologies causing acute arterial occlusions. We investigated neuroprotective effects of kefir on spinal cord ischemia injury in rats. Rats were divided into three groups : 1) sham operated control rats; 2) spinal cord ischemia group fed on a standard diet without kefir pretreatment; and 3) spinal cord ischemia group fed on a standard diet plus kefir. Spinal cord ischemia was performed by the infrarenal aorta cross-clamping model. The spinal cord was removed after the procedure. The biochemical and histopathological changes were observed within the samples. Functional assessment was performed for neurological deficit scores. The kefir group was compared with the ischemia group, a significant decrease in malondialdehyde levels was observed (pkefir group were significantly higher than ischemia group (pkefir group is compared with ischemia group, there was a significant decrease in numbers of dead and degenerated neurons (pkefir group compared with ischemia group (pkefir group were significantly higher than ischemia group at 24 h (pkefir pretreatment in spinal cord ischemia/reperfusion reduced oxidative stress and neuronal degeneration as a neuroprotective agent. Ultrastructural studies are required in order for kefir to be developed as a promising therapeutic agent to be utilized for human spinal cord ischemia in the future.

Investigation of microorganisms involved in biosynthesis of the kefir grain.

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Wang, Sheng-Yao; Chen, Kun-Nan; Lo, Yung-Ming; Chiang, Ming-Lun; Chen, Hsi-Chia; Liu, Je-Ruei; Chen, Ming-Ju

2012-12-01

The purpose of this study was to understand the significance of each microorganism in grain formation by evaluating their microbial aggregation and cell surface properties during co-aggregation of LAB and yeasts together with an investigation of biofilm formation. Non-grain forming strains from viili were also evaluated as a comparison. Results indicated that the kefir grain strains, Lactobacillus kefiranofaciens and Saccharomyces turicensis possess strong auto-aggregation ability and that Lactobacillus kefiri shows significant biofilm formation properties. Significant co-aggregation was noted when S. turicensis and kefir LAB strains (Lb. kefiranofaciens and Lb. kefiri) were co-cultured. Most of the tested LAB strains are hydrophilic and had a negative charge on their cell surface. Only the kefir LAB strains, Lb. kefiranofaciens HL1 and Lb. kefiri HL2, possessed very high hydrophobicity and had a positive cell surface charge at pH 4.2. In contrast, the LAB and yeasts in viili did not show any significant self-aggregation or biofilm formation. Based on the above results, we propose that grain formation begins with the self-aggregation of Lb. kefiranofaciens and S. turicensis to form small granules. At this point, the biofilm producer, Lb. kefiri, then begins to attach to the surface of granules and co-aggregates with other organisms and components in the milk to form the grains. On sub-culturing, more organisms attach to the grains resulting in grain growth. When investigated by scanning electron microscopy, it was found that short-chain lactobacilli such as Lb. kefiri occupy the surface, while long-chain lactobacilli such as Lb. kefiranofaciens have aggregated towards the center of the kefir grains. These findings agree with the above hypothesis on the formation of grains. Taken together, this study demonstrates the importance of cell surface properties together with fermentation conditions to the formation of grains in kefir. Copyright © 2012 Elsevier Ltd. All

Short communication: The effects of frozen storage on the survival of probiotic microorganisms found in traditionally and commercially manufactured kefir.

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O'Brien, K V; Aryana, K J; Prinyawiwatkul, W; Ordonez, K M Carabante; Boeneke, C A

2016-09-01

Kefir is a fermented milk traditionally made from a unique starter culture, which consists of numerous bacteria and yeast species bound together in an exopolysaccharide matrix produced by certain lactic acid bacteria. Many health benefits are associated with traditionally produced kefir; however, bulging and leaking packaging, caused by secondary yeast fermentation during storage, has limited large-scale manufacture. Commercial kefir products have been designed to reduce these effects by using a pure starter culture consisting of a mixture of bacteria and yeast species that give a flavor similar to traditional kefir, but some health benefits may be lost in commercial production due to reduced microbial diversity and lack of beneficial exopolysaccharides. In this study, traditional and commercial kefir was frozen to study the effects of frozen storage on the viability of probiotic bacteria over time. Traditional kefir was prepared by inoculating 1L of pasteurized whole goat milk with approximately 30g of kefir grains. Commercial kefir was prepared by inoculating 1L of full-fat, pasteurized goat milk with a commercial kefir starter. The milk was allowed to ferment at room temperature (24-28°C) until pH 4.6 was reached. Samples were frozen (-8 to -14°C) immediately following the completion of fermentation and were thawed and plated for lactobacilli, lactococci, and yeasts on d 0, 7, 14, and 30 of frozen storage. Lactobacilli, lactococci, and yeasts were significantly reduced in number during frozen storage; however, the traditionally produced kefir was shown to have significantly higher counts of bacteria and yeast at each sampling. We concluded that frozen storage and the development of frozen kefir products could eliminate most packaging concerns associated with the large-scale manufacture of traditionally produced kefir, resulting in increased production and marketability of this healthful product. Copyright © 2016 American Dairy Science Association. Published

Kefir Peptides Prevent Hyperlipidemia and Obesity in High-Fat-Diet-Induced Obese Rats via Lipid Metabolism Modulation.

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Tung, Yu-Tang; Chen, Hsiao-Ling; Wu, Hsin-Shan; Ho, Mei-Hsuan; Chong, Kowit-Yu; Chen, Chuan-Mu

2018-02-01

Obesity has reached epidemic proportions worldwide. Obesity is a complex metabolic disorder that is linked to numerous serious health complications with high morbidity. The present study evaluated the effects of kefir peptides on high fat diet (HFD)-induced obesity in rats. Kefir peptides markedly improved obesity, including body weight gain, inflammatory reactions and the formation of adipose tissue fat deposits around the epididymis and kidney, and adipocyte size. Treating high fat diet (HFD)-induced obese rats with kefir peptides significantly reduced the fatty acid synthase protein and increased the p-acetyl-CoA carboxylase protein to block lipogenesis in the livers. Kefir peptides also increased fatty acid oxidation by increasing the protein expressions of phosphorylated AMP-activated protein kinase, peroxisome proliferator-activated receptor-α, and hepatic carnitine palmitoyltransferase-1 in the livers. In addition, administration of kefir peptides significantly decreased the inflammatory response (TNF-α, IL-1β, and TGF-β) to modulate oxidative damage. These results demonstrate that kefir peptides treatment improves obesity via inhibition of lipogenesis, modulation of oxidative damage, and stimulation of lipid oxidation. Therefore, kefir peptides may act as an anti-obesity agent to prevent body fat accumulation and obesity-related metabolic diseases. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Reduction of Aflatoxin M1 in Milk Using Kefir Starter

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Siavash Kamyar

2017-11-01

Full Text Available Background: Mycotoxins naturally occur in foods. Aflatoxins can cause serious health problems in consumers. Nowadays, biological detoxification method is considered to decrease the aflatoxins level in foods. The aim of this study was to evaluate the effect of kefir starter microorganisms to decrease the aflatoxin M1 (AFM1 levels in milk. Methods: The study was carried out at Shabestar branch, Islamic Azad University in 2016. AFM1 at three levels 150, 200 and 250 ng/L was added to milk samples. Then a pool of lactic acid bacteria (LAB, yeasts and full kefir starter culture was added to milk samples. After cool storage of samples in 4 °C for 7 d, all samples were collected and the level of AFM1 determined by HPLC method. All samples were prepared in triplicate. Results: The highest reduction percentage of AFM1 was observed in yeast (65.33%-68.89% and LAB pool (65%. Samples with full kefir starter showed the reduction percent range of 11.67-34.66% that was lower in compare with other treatment groups. Conclusion: These findings support the ability of LAB and yeasts to bind to aflatoxins in foods. Kefir drink in countries with high contamination by AFM1 in milk can be a safe dairy product choice for consumers.

Evaluation of Kefir as a New Anodic Biocatalyst Consortium for Microbial Fuel Cell.

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Silveira, Gustavo; Schneedorf, José Maurício

2018-02-21

Kefir, a combined consortium of bacteria and yeast encapsulated by a polymeric matrix of exopolysaccharides, was used as anodic biocatalyst in a two-chamber microbial fuel cell (MFC). Fermentation was followed during 72 h and polarization curves were obtained from linear sweep voltammetry. The effect of methylene blue as charge-transfer mediator in the kefir metabolism was evaluated. UV/Vis spectrophotometry and cyclic voltammetry were applied to evaluate the redox state of the mediator and to characterize the electrochemical activity, whereas current interruption was used for internal resistance determination. Aiming to establish a relationship between the microbial development inside the anodic chamber with the generated power in the MFC, total titratable acidity, pH, viscosity, carbohydrate assimilation, and microbial counting were assayed. The kefir-based MFC demonstrated a maximum power density of 54 mW m -2 after 24 h fermentation, revealing the potential use of kefir as a biocatalyst for microbial fuel cells.

Investigation of the Protective Effect of Kefir against Isoproterenol Induced Myocardial Infarction in Rats.

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Mert, Handan; Yılmaz, Hikmet; Irak, Kıvanç; Yıldırım, Serkan; Mert, Nihat

2018-04-01

This study aims to investigate the protective effects of kefir against myocardial infarction induced by isoproterenol (ISO). The rats were randomly divided into 4 groups, each group consisting of 8 rats. The control group, the kefir group (5 mL/kg/d kefir administered to rats as intra-gastric gavage for 60 d), the ISO group (100 mg/kg ISO was administered to rats, s.c. on 61. and 62. d), and kefir+ISO group (5 mL/kg/d kefir was administered to rats intra gastric gavage for 60 days prior to ISO, 100 mg/kg in two doses on day 61 and 62). 12 h after the last ISO dose, all rats were decapitated and their blood samples were collected. Cardiac tissue was reserved for histopathological examination. creatine kinase (CK), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), triglycerides, total cholesterol,very low density lipoprotein (VLDL), low density lipoprotein (LDL), high density lipoprotein (HDL) and glucose were measured by autoanalyzer, whole blood malondialdehyde (MDA), glutathione (GSH) and plasma advanced oxidation protein products (AOPP) levels were measured spectrophotometrically. It was determined that in the group of kefir+ISO, the levels of AST ( p <0.001), CK ( p <0.001), LDH ( p <0.001), MDA ( p <0.001) and AOPP ( p <0.001) were decreased, while the GSH ( p <0.05) increased, compared to ISO group. There were no significant changes in lipid profile and glucose levels between these two groups. In conclusion, by examining cardiac enzymes and histopathological changes in cardiac tissue, it can be concluded that the administration of kefir in myocardial infarction induced by ISO can protect the heart with its antioxidant characteristic and minimize the toxic damage created by ISO.

Kefir exhibits anti‑proliferative and pro‑apoptotic effects on colon adenocarcinoma cells with no significant effects on cell migration and invasion.

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Khoury, Nathalie; El-Hayek, Stephany; Tarras, Omayr; El-Sabban, Marwan; El-Sibai, Mirvat; Rizk, Sandra

2014-11-01

Kefir, a fermented milk product, exhibits anti‑tumoral activity in vivo; yet its mechanism of action remains elusive. Recent studies have focused on the mechanism of action of kefir on cancer cells in vitro. The current study aims at examining the effect of kefir on cell survival, proliferation, and motility of colorectal cancer (CRC) cells. Kefir's anti‑cancer potential was tested on CRC cell lines, Caco‑2 and HT‑29, through cytotoxicity, proliferation, and apoptotic assays. The expression of certain genes involved in proliferation and apoptosis was measured using reverse transcriptase‑polymerase chain reaction (RT‑PCR) and western blotting. To assess the effect of kefir on cancer metastasis, wound‑healing and time‑lapse movies, in addition to collagen‑based invasion assay, were used. The results show that cell‑free fractions of kefir exhibit an anti‑proliferative effect on Caco‑2 and HT‑29 cells. Analysis of DNA content by flow cytometry revealed the ability of kefir to induce cell cycle arrest at the G1 phase. Kefir was also found to induce apoptosis, as seen by cell death ELISA. Results from RT‑PCR showed that kefir decreases the expression of transforming growth factor α (TGF‑α); and transforming growth factor‑β1 (TGF‑β1) in HT‑29 cells. Western blotting results revealed an upregulation in Bax:Bcl‑2 ratio, confirming the pro‑apoptotic effect of kefir, and an increase in p53 independent‑p21 expression upon kefir treatment. MMP expression was not altered by kefir treatment. Furthermore, results from time‑lapse motility movies, wound‑healing, and invasion assays showed no effect on the motility of colorectal as well as breast (MCF‑7 and MB‑MDA‑231) cancer cells upon kefir treatment. Our data suggest that kefir is able to inhibit the proliferation and induce apoptosis in HT‑29 and Caco‑2 CRC cells, yet it does not exhibit a significant effect on the motility and invasion of these cells in vitro.

PENGARUH PEMBERIAN KEFIR BENING TERHADAP KADAR GLUKOSA DARAH PADA TIKUS WISTAR HIPERGLIKEMIA YANG DIINDUKSI STREPTOZOTOCIN (STZ

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Judiono Judiono

2012-11-01

Full Text Available ABSTRACT Background: Hyperglycemia in diabetes caused by excessive free-radicals, which in turn increases reactive oxygen species, reduced immune function and antioxidant, the beta cell damage. Objective: To validate the effects of plain kefir probiotic on blood glucose level in streptozotocin (STZ induced hyperglycemia Wistar rats. Methods: The experiment using randomized pretest-posttest control group design was carried-out on 48 male hyperglycemia Wistar rats induced by 40 mg/kg body-weight of STZ. Rats were divided randomly into four groups: (1 negative control fed ad libitum standard diet, (2 positive control induced by STZ, (3 insulin treated 0.76 UI/200 g body weight, and (4 plain kefir 3.6 cc per day. Kefir is prepared by the use of pasteurized skim milk fermented by kefir commercial inoculums. Blood glucose was measured with Super Glucocard II meter (Arkray, Kyoto, Japan. Results Kefir supplementation 3.6 cc per day had significantly effect on blood glucose reduction after… days. Results showed that blood glucose levels before and after the treatment in each group as follows: in negative control group, before and after the treatment were 92.7 ± 6.6 mgdL and 89.4 ± 5.3 mgdL, respectively; in positive control group, before and after treatment were 263.9 ± 61.7 mgdL and 290.9 ± 99.8 mgdL; in insulin group, before and after the treatment were 286.9 ± 73.2 mgdL and 168.3 ± 53.3 mgdL; and in kefir group, before and after the treatment were 234.0 ± 61.1 mgdL and 147.8 ± 52.6 mgdL. Conclusion: Kefir supplementation significantly reduced blood glucose in vivo. Isolation and identification of probiotic involved on biomolecular and to find out the role of specific probiotic originated from kefir in diabetes mellitus are very challenging to be implemented in clinical application. [Penel Gizi Makan 2009, 32(2: 129-136] Key words: probiotic, kefir, diabetes mellitus, hyperglicemia, streptozotocin

Rheological, texture and sensory properties of kefir from mare’s milk and its mixtures with goat and sheep milk

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Dorota Cais-Sokolińska

2016-11-01

Full Text Available The aim of this study was to conduct lactic acid-alcoholic fermentation using mesophilic lactic acid bacteria (LAB for mare’s milk and its mixture with goat and sheep milk, followed by instrumental and sensory characteristic of the texture profile in the produced kefirs. It was shown that kefirs made from a mixture of goat and sheep milk are firmer, have greater values of consistency and the viscosity index than those produced from mare’s milk alone. Kefir storage for 3 weeks causes changes in their mechanical properties. Exceptions are found for firmness of kefirs made from both mixtures and the viscosity index of kefir made from sheep milk, which remained stable. The most divergent texture profile of the tested kefirs was reflected in the sensory examined descriptors of prickling, dense and mouth-coating sensation.

Thermal analysis of dry eye subjects and the thermal impulse perturbation model of ocular surface.

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Zhang, Aizhong; Maki, Kara L; Salahura, Gheorghe; Kottaiyan, Ranjini; Yoon, Geunyoung; Hindman, Holly B; Aquavella, James V; Zavislan, James M

2015-03-01

In this study, we explore the usage of ocular surface temperature (OST) decay patterns to distinguished between dry eye patients with aqueous deficient dry eye (ADDE) and meibomian gland dysfunction (MGD). The OST profiles of 20 dry eye subjects were measured by a long-wave infrared thermal camera in a standardized environment (24 °C, and relative humidity (RH) 40%). The subjects were instructed to blink every 5 s after 20 ∼ 25 min acclimation. Exponential decay curves were fit to the average temperature within a region of the central cornea. We find the MGD subjects have both a higher initial temperature (p model, referred to as the thermal impulse perturbation (TIP) model. We conclude that long-wave-infrared thermal imaging is a plausible tool in assisting with the classification of dry eye patient. Copyright © 2015 Elsevier Ltd. All rights reserved.

Short communication: Sensory analysis of a kefir product designed for active cancer survivors.

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O'Brien, K; Boeneke, C; Prinyawiwatkul, W; Lisano, J; Shackelford, D; Reeves, K; Christensen, M; Hayward, R; Ordonez, K Carabante; Stewart, L K

2017-06-01

Kefir is a fermented milk product that is a good source of protein and health-promoting bacteria. It has the potential to improve recovery from exercise and the health and well-being of cancer survivors. The purpose of this study was to explore cancer survivor attitudes about and acceptance of a kefir recovery beverage made from cultured milk, whole fruit, natural sweeteners, and other natural ingredients. Kefir was made by inoculating and fermenting milk with kefir grains. The kefir was then mixed with a fruit base and given to cancer survivors (n = 52) following a bout of exercise. Participants evaluated the acceptability of the beverage samples (overall appearance, aroma, taste, mouthfeel, and overall liking) using a 9-point hedonic scale, and they evaluated the smoothness using a 3-category just-about-right scale (not enough, just about right, and too much). They also expressed their physical and psychological feelings about the beverage using a 5-point scale (1 = not at all to 5 = extremely) and indicated their purchase intent using a binomial (yes/no) response. The health benefits of kefir were then explained, and participants sampled a second beverage (the same product), answering the same questions related to overall liking, feeling, and intent to purchase. We used a paired Student's t-test to compare beverage liking and emotion scores before and after participants learned about the health benefits of kefir. Data are presented as mean ± standard deviations. The beverage scored significantly higher for overall liking after the health benefits were explained (6.5 ± 1.8 and 7.0 ± 1.7 out of 9 before and after the explanation of health benefits, respectively). Participants showed a high intent to purchase before they learned about the health benefits (75% of participants indicated an intent to purchase, and 89% after they learned about the health benefits). The beverage received high scores overall and, except for an improvement in overall liking, we

Characterization and stability of lactobacilli and yeast microbiota in kefir grains.

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Vardjan, T; Mohar Lorbeg, P; Rogelj, I; Čanžek Majhenič, A

2013-05-01

Characterization and stability of lactobacilli and yeasts from kefir grains using culture-dependent and culture-independent methods were investigated in this study. Culture-dependent analysis, followed by sequencing of 16S ribosomal DNA for bacteria and 26S rRNA gene for yeasts, revealed 3 different species of lactobacilli and yeasts, respectively. The most frequently isolated bacterial species were Lactobacillus kefiranofaciens ssp. kefirgranum, Lb. parakefiri, and Lb. kefiri, whereas yeasts belonged to Kluyveromyces marxianus, Kazachstania exigua, and Rhodosporidium kratochvilovae. This study is the first to report on the presence of R. kratochvilovae in kefir grains. On the other hand, PCR-denaturing gradient gel electrophoresis in the culture-independent method showed that the dominant microorganisms were Lb. kefiranofaciens ssp. kefirgranum, Kl. marxianus and Ka. exigua, but did not reveal bands corresponding to Lb. parakefiri, Lb. kefiri, or R. kratochvilovae. Our results support the necessity of combining more techniques for detailed and reliable study of microbial communities in kefir grains. Another interesting finding confirmed that the detected dominant microbiota of kefir grains is very stable and did not change over experimental time. This finding is important to ensure consistent product quality. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Pengaruh suhu dan lama pemeraman pada inkubator terhadap kualitas fisik kefir

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Herly Evanuarini

2014-08-01

Full Text Available The objective of the research was to find out the optimum temperature and ripening duration in incubator to produce kefir which had physical quality that met the standard of fermented milk quality. The method of experiment was factorial randomized block design. The first factor was temperature that consisted of 25oC, 30oC and 35oC. The second factor was ripening duration that consisted of 12 hours, 18 hours and 24 hours. The result showed that the temperature and duration of ripening gave a highly significant effect (P<0.01 on pH and viscosity. The combination of temperature (30oC and ripening duration (24 hours produced kefir which met the standard of Indonesian industry fermented milk such as pH (3.86 and viscosity 157.6 cps. Keywords: Temperature, ripening duration, kefir

Water Kefir grain as a source of potent dextran producing lactic acid bacteria

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Davidović Slađana Z.

2015-01-01

Full Text Available Water kefir is abeverage fermented by a microbial consortium captured in kefir grains. The kefir grains matrix is composed of polysaccharide, primarily dextran, whichis produced by members of the microbial consortium. In this study, we have isolated lactic acid bacteria (LAB from non-commercial water kefir grains (from Belgrade, Serbia and screened for dextran production. Among twelve Lisolates threeproduced slime colonies on modified MRS (mMRS agar containing sucrose instead of glucoseand were presumed to produce dextran. Three LABwere identified based on morphological, physiological and biochemical characteristics and 16S rRNA sequencing as Leuconostoc mesenteroides(strains T1 and T3 and Lactobacillus hilgardii (strain T5. The isolated strains were able to synthesize a substantial amount of dextran in mMRS broth containing 5% sucrose. Maximal yields (11.56, 18.00 and 18.46 g/l were obtained after 16h, 20h and 32h for T1, T3 and T5, respectively. Optimal temperature for dextran production was 23oC for two Leuconostoc mesenteroides strains and 30oC for Lactobacillus hilgardii strain. The produced dextrans were identified based on paper chromatography while the main structure characteristics of purified dextranwere observed by FT-IR spectroscopy. Our study shows that water kefir grains are a natural source of potent dextranproducing LAB. [Projekat Ministarstva nauke Republike Srbije, br. TR 31035

Effects of thermal drying on phosphorus availability from iron-precipitated sewage sludge

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Lemming, Camilla; Scheutz, Charlotte; Bruun, Sander

2017-01-01

Thermal drying of sewage sludge implies sanitation and improves practical handling options of the sludge prior to land application. However, it may also affect its value as a fertilizer. The objective of this study was to assess whether thermal drying of sewage sludge, as well as drying temperature...

Characterization of lactic acid bacteria from local cow´s milk kefir

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Ismail, YS; Yulvizar, C.; Mazhitov, B.

2018-03-01

One of products from milk fermentation is kefir. It is made by adding kefir grains which are composed of lactic acid bacteria and yeast into milk. The lactic acid bacteria are a group of bacteria that produce antimicrobial substances and able to inhibit the growth of pathogenic bacteria. In this research, the lactic acid bacteria were isolated from Aceh local cow`s milk kefir to determine the genus of the isolates. The methods used in the characterization of lactic acid bacteria are colony morphology, cell morphology, and biochemical tests which includes a catalase test; 5%, 6.5%, and 10% salt endurance tests; 37°C and 14°C temperature endurance tests, SIM test, TSIA test, MR-VP test, and O/F test. Of the four isolates found from the cow’s milk kefir, two isolates were confirmed as lactic acid bacteria (isolates SK-1 and SK-4). Both isolates are Gram positive bacteria, and have negative catalase activity. From the observations of colony morphology, cell morphology, and biochemical tests, it was found that the genus of SK-1 is Lactobacillus and the genus of SK-4 is Enterococcus.

Donkey milk kefir induces apoptosis and suppresses proliferation of Ehrlich ascites carcinoma by decreasing iNOS in mice.

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Esener, Obb; Balkan, B M; Armutak, E I; Uvez, A; Yildiz, G; Hafizoglu, M; Yilmazer, N; Gurel-Gurevin, E

2018-04-12

Donkey milk and donkey milk kefir exhibit antiproliferative, antimutagenic and antibacterial effects. We investigated the effects of donkey milk and donkey milk kefir on oxidative stress, apoptosis and proliferation in Ehrlich ascites carcinoma (EAC) in mice. Thirty-four adult male Swiss albino mice were divided into four groups as follows: group 1, administered 0.5 ml water; group 2, administered 0.5 ml water + EAC cells; group 3, administered 0.5 ml donkey milk + EAC cells; group 4, administered 0.5 ml donkey milk kefir + EAC cells. We introduced 2.5 x 10 6 EAC cells into each animal by subcutaneous injection. Tap water, donkey milk and donkey milk kefir were administered by gavage for 10 days. Animals were sacrificed on day 11. After measuring the short and long diameters of the tumors, tissues were processed for histology. To determine oxidative stress, cell death and proliferation iNOS and eNOS, active caspase-3 and proliferating cell nuclear antigen were assessed using immunohistochemistry. A TUNEL assay also was used to detect apoptosis. Tumor volume decreased in the donkey milk kefir group compared to the control and donkey milk groups. Tumor volume increased in the donkey milk group compared to the control group. Proliferating cell nuclear antigen levels were higher in the donkey milk kefir group compared to the control and donkey milk groups. The number of apoptotic cells was less in the donkey milk group, compared to the control, whereas it was highest in the donkey milk kefir group. Donkey milk administration increased eNOS levels and decreased iNOS levels, compared to the control group. In the donkey milk kefir group, iNOS levels were significantly lower than those of the control and donkey milk groups, while eNOS levels were similar to the control group. Donkey milk kefir induced apoptosis, suppressed proliferation and decreased co-expression of iNOS and eNOS. Donkey milk promoted development of the tumors. Therefore, donkey milk kefir appears to

Kefir fermented milk and kefiran promote growth of Bifidobacterium bifidum PRL2010 and modulate its gene expression.

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Serafini, Fausta; Turroni, Francesca; Ruas-Madiedo, Patricia; Lugli, Gabriele Andrea; Milani, Christian; Duranti, Sabrina; Zamboni, Nicole; Bottacini, Francesca; van Sinderen, Douwe; Margolles, Abelardo; Ventura, Marco

2014-05-16

Bifidobacteria constitute one of the dominant groups of microorganisms colonizing the human gut of infants. Their ability to utilize various host-derived glycans as well as dietary carbohydrates has received considerable scientific attention. However, very little is known about the role of fermented foods, such as kefir, or their constituent glycans, such as kefiran, as substrates for bifidobacterial growth and for the modulation of the expression of bifidobacterial host-effector molecules. Here, we show that Bifidobacterium bifidum PRL2010 exhibits high growth performance among the bifidobacterial strains tested when cultivated on kefir and/or kefiran polymer. Furthermore, a 16S rRNA metagenomic approach revealed that the microbiota of kefir is modified upon the addition of PRL2010 cells to the kefir matrix. Finally, our results show that kefir and kefiran are able to influence the transcriptome of B. bifidum PRL2010 causing increased transcription of genes involved in the metabolism of dietary glycans as well as genes that act as host-microbe effector molecules such as pili. Altogether, these data support the use of kefir as a valuable means for the delivery of effective microbial cells in probiotic therapy. Copyright © 2014 Elsevier B.V. All rights reserved.

Coffee Flower Honey (Coffea sp. Addition to Kefir Quality Based on Microbiology Characteristic

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Astri Wulandari

2017-11-01

Full Text Available The Objective of this research was to determine the best concentration of addition coffee flower honey to kefir based on total plate count, lactic acid bacteria, acidity, and pH value. The materials used in this research were honey kefir made from cow’s milk, kefir grains, and coffee flowers honey. The method used in this research was experimental with Completely Randomized Design by 4 treatments and 4 replications and continued by using Duncan’s Multiple Range Test. The result showed that the effect of addition coffee flowers honey was not significantly different (P>0.05 on total plate count, lactic acid bacteria, acidity, give highly significant different (P<0.01 on pH value. Addition 20% of  coffee flower honey was the best treatment with quality of total plate count 6.21 ± 0.60 log CFU/mL, total lactic acid bacteria 6.16 ± 0.14 log CFU/mL, acidity 0.76 ± 0.11 % and pH value 3.596 ± 0.021. Further study is needed to figure the storability of honey kefir.

Stability Emulsion and Sensory Characteristics Low Fat Mayonnaise Using Kefir as Emulsifier Replacer

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Herly Evanuarini

2017-03-01

Full Text Available Mayonnaise is a kind of semi solid oil in water (o/w emulsion which containing pasteurized egg yolk as an emulsifier. The consumers have demanded that the use of egg yolk be reduced. Kefir was used to develop a low fat mayonnaise as emulsifier replacer to egg yolk. The objective of this research was to observe the emulsion stability, sensory characteristics of low fat mayonnaise prepare during kefir as emulsifier replacer. The research method was using experimental design. The result showed that formulation of low fat mayonnaise by using Rice bran oil 40%, kefir 20% produces the optimal low fat mayonnaise in emulsion stability and accepted by the panelist.

Influence of Different Growth Conditions on the Kefir Grains Production, used in the Kefiran Synthesis

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Carmen Rodica Pop

2014-11-01

Full Text Available The purpose of this study was to optimize the kefir grains biomass production, using milk as culture media. The kefir grains were cultured at different changed conditions (temperature, time, shaker rotating speed, culture media supplemented to evaluate their effects. Results showed that optimal culture conditions were using the organic skim milk, incubated at 25°C for 24 hours with a rotation rate of 125 rpm. According to results, the growth rate was 38.9 g/L for 24 h, at 25°C using the organic milk - OSM, 36.87 g/L during 24 hours, optimal time for propagation process gave 37.93 g/L kefir grains biomass when the effect of temperature level was tested. The homogenization of medium with shaker rotating induced a greater growth rate, it was obtained 38.9 g/L for 24 h, at 25°C using rotation rate at 125 rpm. The growing medium (conventional milk supplemented with different minerals and vitamins may lead to improve the growth conditions of kefir grains biomass. The optimization of the growth environment is very important for achieving the maximum production of kefir grains biomass, substrate necessary to obtain the polysaccharide kefiran

Identification and Relative Quantification of Bioactive Peptides Sequentially Released during Simulated Gastrointestinal Digestion of Commercial Kefir.

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Liu, Yufang; Pischetsrieder, Monika

2017-03-08

Health-promoting effects of kefir may be partially caused by bioactive peptides. To evaluate their formation or degradation during gastrointestinal digestion, we monitored changes of the peptide profile in a model of (1) oral, (2) gastric, and (3) small intestinal digestion of kefir. Matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy analyses revealed clearly different profiles between digests 2/3 and kefir/digest 1. Subsequent ultraperformance liquid chromatography-electrospray ionization-tandem mass spectrometry identified 92 peptides in total (25, 25, 43, and 30, partly overlapping in kefir and digests 1, 2, and 3, respectively), including 16 peptides with ascribed bioactivity. Relative quantification in scheduled multiple reaction monitoring mode showed that many bioactive peptides were released by simulated digestion. Most prominently, the concentration of angiotensin-converting enzyme inhibitor β-casein 203-209 increased approximately 10 000-fold after combined oral, gastric, and intestinal digestion. Thus, physiological digestive processes may promote bioactive peptide formation from proteins and oligopeptides in kefir. Furthermore, bioactive peptides present in certain compartments of the gastrointestinal tract may exert local physiological effects.

Bolo de "chocolate" produzido com pó de cupuaçu e kefir "Chocolate" pound cake with cupuassu and kefir

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Mauricio Sergio Esteller

2006-09-01

Full Text Available Nos últimos anos vem ocorrendo a valorização dos recursos e produtos naturais. Cresce em todo o mundo a preocupação com a conservação do meio ambiente e a valorização dos recursos da flora e fauna. É forte a demanda por tecnologias de processo, de produto e de aplicação. Neste estudo foi utilizada formulação padronizada para bolo tipo inglês, substituindo cacau em pó por cupuaçu em pó e com adição de kefir, mantendo-se o total de sólidos. O tempo e a temperatura de assamento foram fixados em 50 minutos e 180 ºC. Foram avaliados a porosidade do miolo, o perfil de textura, cor, umidade, volume específico e densidade da massa. Os resultados mostraram que a adição de pó de cupuaçu não altera as características do bolo padrão elaborado com cacau e que a adição de kefir modifica a textura e a porosidade do miolo.In the last years, natural resources and products have gained the attention of consumers. The concern with the conservation of the environment and the importance of the flora and fauna increases in the whole world. The demand for application, product, and process technologies is strong. In this study, a control chocolate pound cake formula was used changing cocoa powder from the original formula to cupuassu powder and adding kefir, keeping the amounts of total solids. The time and temperature were fixed in 50 minutes and 180 ºC. Crumb porosity, texture profile analysis (TPA, color, moisture, specific volume, and dough density were evaluated. The results showed that cupuassu powder can be used as a cocoa replacer in "chocolate" cake production and that kefir changed the texture and crumb porosity of the cake.

The Effect of Heating and Postfermentation on Lactoferrin of Fresh and Kefir Goat Milk

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Erfan Kustiawan

2012-02-01

Full Text Available The aim of this study was determinated of lactoferrin profile in goat milk and kefir. The samples were collected from whey raw milk, pasteurized and kefir. Lactoferrin profile in this study consisted of concentration and molecule weight of lactoferrin. Goat lactoferrin was isolated from whey by fractionation on sephadex     G-100 column, it was eluted at 0.1 M phosphate buffer pH 6.8. Characterization of goat lactoferrin by electrophoretic SDS-PAGE techniques detected molecule weight of goat lactoferrin that the isolate of the fractions from fractionation on sephadex G-100 column. Result of the research  showed that pasteurization during storage after fermentation process were influenced by concentration of lactoferrin significant (P<0.05. The molecule weights of lactoferrin in goat milk and kefir were estimated at 84 kDa and 80 kDa. The average concentration of goat lactoferrin at 1.915 mg/ml (without pasteurized, 1.579 mg/ml (pasteurized at 65oC, 0.954 mg/ml (pasteurized at 73oC and 0.322 mg/ml (pasteurized at 83oC. The average concentration of goat lactoferrin in kefir during storage at 0.663 mg/ml (0 day, 0.448 mg/ml (3  day, 0.249 mg/ml (6 day, 0.142 mg/ml (9 day dan 0.048 mg/ml (12 day.  Pasteurization at temperature 65oC 30’’ can defend concentration of lactoferrin higher than temperature 73oC 15’’  and temperature 83oC 2’’. Concentration of lactoferrin in kefir were defended until 12 day storage.   Keywords : Lactoferrin, goat milks, kefir

Short communication: Evaluation of the microbiota of kefir samples using metagenetic analysis targeting the 16S and 26S ribosomal DNA fragments.

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Korsak, N; Taminiau, B; Leclercq, M; Nezer, C; Crevecoeur, S; Ferauche, C; Detry, E; Delcenserie, V; Daube, G

2015-06-01

Milk kefir is produced by fermenting milk in the presence of kefir grains. This beverage has several benefits for human health. The aim of this experiment was to analyze 5 kefir grains (and their products) using a targeted metagenetic approach. Of the 5 kefir grains analyzed, 1 was purchased in a supermarket, 2 were provided by the Ministry of Agriculture (Namur, Belgium), and 2 were provided by individuals. The metagenetic approach targeted the V1-V3 fragment of the 16S ribosomal (r)DNA for the grains and the resulting beverages at 2 levels of grain incorporation (5 and 10%) to identify the bacterial species population. In contrast, the 26S rDNA pyrosequencing was performed only on kefir grains with the aim of assessing the yeast populations. In parallel, pH measurements were performed on the kefir obtained from the kefir grains using 2 incorporation rates. Regarding the bacterial population, 16S pyrosequencing revealed the presence of 20 main bacterial species, with a dominance of the following: Lactobacillus kefiranofaciens, Lactococcus lactis ssp. cremoris, Gluconobacter frateurii, Lactobacillus kefiri, Acetobacter orientalis, and Acetobacter lovaniensis. An important difference was noticed between the kefir samples: kefir grain purchased from a supermarket (sample E) harbored a much higher proportion of several operational taxonomic units of Lactococcus lactis and Leuconostoc mesenteroides. This sample of grain was macroscopically different from the others in terms of size, apparent cohesion of the grains, structure, and texture, probably associated with a lower level of Lactobacillus kefiranofaciens. The kefir (at an incorporation rate of 5%) produced from this sample of grain was characterized by a lower pH value (4.5) than the others. The other 4 samples of kefir (5%) had pH values above 5. Comparing the kefir grain and the kefir, an increase in the population of Gluconobacter in grain sample B was observed. This was also the case for Acetobacter orientalis

The effects of postexercise consumption of a kefir beverage on performance and recovery during intensive endurance training.

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O'Brien, K V; Stewart, L K; Forney, L A; Aryana, K J; Prinyawiwatkul, W; Boeneke, C A

2015-11-01

This study was designed to determine whether kefir accentuates the positive health benefits assessed by measures in fitness, body composition, or both, as a measure of cardiovascular disease risk as well as the biomarker C-reactive protein (CRP). Sixty-seven adult males and females aged 18 to 24 yr were assigned to 1 of 4 groups: (1) endurance training + control beverage, (2) endurance training +kefir beverage,(3) active control + control beverage, or (4) active control + kefir beverage. The exercise groups completed 15 wk of structured endurancetraining while the active control groups maintained their usual exercise routine. Additionally, each group was assigned to either a kefir or a calorie/macronutrient matched placebo beverage that was consumed twice per week. No significant interactions were found among groups with respect to outcome variables with the exception of serum CRP. The endurance training was effective in improving 1.5-mile (2.41 km) times and kefir supplementation may have been a factor in attenuating the increase in CRP that was observed over the course of the intervention period. This preliminary study suggests that kefir may be involved in improving the risk profile for cardiovascular disease as defined by CRP. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Thermal fluctuation based study of aqueous deficient dry eyes by non-invasive thermal imaging.

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Azharuddin, Mohammad; Bera, Sumanta Kr; Datta, Himadri; Dasgupta, Anjan Kr

2014-03-01

In this paper we have studied the thermal fluctuation patterns occurring at the ocular surface of the left and right eyes for aqueous deficient dry eye (ADDE) patients and control subjects by thermal imaging. We conducted our experiment on 42 patients (84 eyes) with aqueous deficient dry eyes and compared with 36 healthy volunteers (72 eyes) without any history of ocular surface disorder. Schirmer's test, Tear Break-up Time, tear Meniscus height and fluorescein staining tests were conducted. Ocular surface temperature measurement was done, using an FL-IR thermal camera and thermal fluctuation in left and right eyes was calculated and analyzed using MATLAB. The time series containing the sum of squares of the temperature fluctuation on the ocular surface were compared for aqueous deficient dry eye and control subjects. Significant statistical difference between the fluctuation patterns for control and ADDE was observed (p eyes are significantly correlated in controls but not in ADDE subjects. The possible origin of such correlation in control and lack of correlation in the ADDE subjects is discussed in the text. Copyright © 2014 Elsevier Ltd. All rights reserved.

Anti-inflammatory and angiogenic activity of polysaccharide extract obtained from Tibetan kefir.

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Prado, Maria Rosa Machado; Boller, Christian; Zibetti, Rosiane Guetter Mello; de Souza, Daiany; Pedroso, Luciana Lopes; Soccol, Carlos Ricardo

2016-11-01

The search for new bioactive molecules is a driving force for research pharmaceutical industries, especially those molecules obtained from fermentation. The molecules possessing angiogenic and anti-inflammatory attributes have attracted attention and are the focus of this study. Angiogenic activity from kefir polysaccharide extract, via chorioallantoic membrane assay, exhibited a pro-angiogenic effect compared with vascular endothelial factor (pro-angiogenic) and hydrocortisone (anti-angiogenic) activity as standards with an EC50 of 192ng/mL. In terms of anti-inflammatory activity determined via hyaluronidase enzyme assay, kefir polysaccharide extract inhibited the enzyme with a minimal activity of 2.08mg/mL and a maximum activity of 2.57mg/mL. For pharmaceutical purposes, kefir polysaccharide extract is considered to be safe because it does not inhibit VERO cells in cytotoxicity assays. Copyright © 2016 Elsevier Inc. All rights reserved.

Microbial profile of a kefir sample preparations: grains in natura and lyophilized and fermented suspension

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Rafaela Strada de Oliveira Bergmann

2010-12-01

Full Text Available Probiotics are supplementary foods developed by microbial strains that improve animal health beyond basic nutrition. Probiotics are consumed orally, regardless of being considered as normal inhabitants of the intestines, able to survive in enzimatic and biliary secretions. Kefir is a probiotic originated from the old continent, fermented by several bacteria and yeasts, encapsulated in a polyssacharide matrix, and resembles jelly grains. Kefir is also presented as its sourish product both in sugary or milky suspensions containing vitamins, aminoacids, peptides, carbohydrates, ethanol, and volatile compounds. Kefir is known to have a diverse microbial content depending on the country and fermentative substrates, which cause distinct probiotic effects. In this sense, the purpose of this work was to isolate, identify, and quantify the microbial content of a native sugary kefir sample (fermented suspension and lyophilized natural grains. Serial dilutions were plated on Rogosa agar (AR and De Man, Rogosa and Sharpe (MRS, for Lactobacillus; Brain Heart Infusion (BHI, for total bacteria; Sabouraud-Dextrose-Agar (SDA, for yeasts and filamentous fungi; Thioglycolate Agar (TA, for Streptococcus, Acetobacteria and Leuconostoc; and Coconut Water Agar (CWA, and CWA supplemented with yeast extract (CWAY, for various genera. Genera and species for all strains were identified through biochemical reactions and specific API systems. The microbial profile of kefir was different from other sources of grains despite the presence of similar microorganisms and others which have not been reported yet. The data obtained with the CWA and CWAE media suggest that both substrates are alternative and salutary media for culture of kefir strains.

Effect of Safflower Oil on Concentration of Conjugated Linoleic Acid of Kefir Prepared by Low-fat Milk.

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Farsad-Naeimi, Alireza; Imani, Saeid; Arefhosseini, Seyed R; Alizadeh, Mohammad

2015-01-01

Conjugated linoleic acid (CLA) is a special fatty acid in dairy products with unique antioxidant and anti-cancerous effects. Kefir, a milk product, comprises normalized homogenized cow's milk, the fructose and lactulose syrup as well as a symbiotic starter which has improved probiotic characteristics. The study was aimed to discuss patents and to examine the effect of different safflower oil concentrations on CLA content of the kefir drink prepared by low-fat milk. Safflower oil was added at 0.1, 0.3 and 0.5% (V/V) to low-fat cow's milk and six formulations of kefir samples were prepared. The CLA content of the kefir products was measured at pH=6.0 and pH=6.8 by gas chromatography. Acid and bile tolerance of bacterial microenvironment in the products were also determined. Substitution of natural fat content of milk with safflower oil resulted in proportional increase in the CLA contents of kefir in a dose dependent manner. The highest concentration of CLA was found under 0.5% (V/V) of safflower oil at pH 6.0 and temperature of 37 °C. Adding the Safflower oil into milk used for kefir production, increased CLA content from 0.123 (g/100 g) in pure safflower free samples to 0.322 (g/100 g) in samples with 0.5% (V/V) of safflower oil. The current study revealed that substitution of safflower oil with natural fat of cow's milk may help the production of kefir samples with remarkable increase in CLA content of final product.

Thermal Analysis of a Dry Storage Concept for Capsule Dry Storage Project

International Nuclear Information System (INIS)

JOSEPHSON, W.S.

2003-01-01

There are 1,936 cesium (Cs) and strontium (Sr) capsules stored in pools at the Waste Encapsulation and Storage Facility (WESF). These capsules will be moved to dry storage on the Hanford Site as an interim measure to reduce risk. The Cs/Sr Capsule Dry Storage Project is conducted under the assumption that the capsules will eventually be moved to the repository at Yucca Mountain, and the design criteria include requirements that will facilitate acceptance at the repository. The storage system must also permit retrieval of capsules in the event that vitrification of the capsule contents is pursued. The Capsule Advisory Panel (CAP) was created by the Project Manager for the Hanford Site Capsule Dry Storage Project (CDSP). The purpose of the CAP is to provide specific technical input to the CDSP; to identify design requirements; to ensure design requirements for the project are conservative and defensible; to identify and resolve emerging, critical technical issues, as requested; and to support technical reviews performed by regulatory organizations, as requested. The CAP will develop supporting and summary documents that can be used as part of the technical and safety bases for the CDSP. The purpose of capsule dry storage thermal analysis is to: (1) Summarize the pertinent thermal design requirements sent to vendors, (2) Summarize and address the assumptions that underlie those design requirements, (3) Demonstrate that an acceptable design exists that satisfies the requirements, (4) Identify key design features and phenomena that promote or impede design success, (5) Support other CAP analyses such as corrosion and integrity evaluations, and (6) Support the assessment of proposed designs. It is not the purpose of this report to optimize or fully analyze variations of postulated acceptable designs. The present evaluation will indicate the impact of various possible design features, but not systematically pursue design improvements obtainable through analysis

Kefir reduces insulin resistance and inflammatory cytokine expression in an animal model of metabolic syndrome.

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Rosa, Damiana D; Grześkowiak, Łukasz M; Ferreira, Célia L L F; Fonseca, Ana Carolina M; Reis, Sandra A; Dias, Mariana M; Siqueira, Nathane P; Silva, Leticia L; Neves, Clóvis A; Oliveira, Leandro L; Machado, Alessandra B F; Peluzio, Maria do Carmo G

2016-08-10

There is growing evidence that kefir can be a promising tool in decreasing the risk of many diseases, including metabolic syndrome (MetS). The aim of the present study was to evaluate the effect of kefir supplementation in the diet of Spontaneously Hypertensive Rats (SHR) in which MetS was induced with monosodium glutamate (MSG), and to determine its effect on metabolic parameters, inflammatory and oxidation marker expression and glycemic index control. Thirty animals were used in this experiment. For the induction of MetS, twenty two-day-old male SHR received five consecutive intradermal injections of MSG. For the Negative Control, ten newborn male SHR received intradermal injections of saline solution (0.9% saline solution). After weaning, animals received standard diet and water ad libitum until reaching 3 months old, for the development of MetS. They were then divided into three groups (n = 10): negative control (NC, 1 mL saline solution per day), positive control (PC, 1 mL saline solution per day) and the Kefir group (1 mL kefir per day). Feeding was carried out by gavage for 10 weeks and the animals received standard food and water ad libitum. Obesity, insulin resistance, pro- and anti-inflammatory markers, and the histology of pancreatic and adipose tissues were among the main variables evaluated. Compared to the PC group, kefir supplementation reduced plasma triglycerides, liver lipids, liver triglycerides, insulin resistance, fasting glucose, fasting insulin, thoracic circumference, abdominal circumference, products of lipid oxidation, pro-inflammatory cytokine expression (IL-1β) and increased anti-inflammatory cytokine expression (IL-10). The present findings indicate that kefir has the potential to benefit the management of MetS.

Efficacy of Kefir on the Release of Lysosomal Proteases After Expremintal Spinal Cord Trauma

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Emre Delen

2015-11-01

Full Text Available Aim: Prevention of secondary injury developing as a result of spinal cord injury will reduce significantly neurological deficits which may occur after trauma. These are focused in experimental studies and many agents are being tested. In our study, we have invesitigated the effects of kefir, which is a a probiotic, associated with life prolongation, whose antioxidant and lipid peroxidation effects were revealed on despite the scientific studies were limited, on lipid peroxidation and lysosomal proteases which play important roles in spinal cord. Material and Method: In the study, female Sprague Dawley rats weighing 200 to 250 g were used. The study was conducted on five groups with a total of 40 rats including the control, trauma, trauma treatment, trauma treatment kefir and trauma kefir groups. The high-dose methylprednisolone was used as the therapy. Spinal cord trauma was performed with clip compression method at the level of T10. Kefir was given to rats via orogastric ways, prior to trauma for 7 days at a dose of 2 * 1cc/100g. All rats were sacrificed 48 hours after treatment. The changes in the value of tissue cathepsins B and L, MDA and histopathological changes were examined. Results: It has been found in our study according to the review of biochemical values that; kefir did not reduce significantly cathepsin B values compared to the treatment group (p> 0.05, did reduce significantly MDA value compared to treatment group (p

Modern perspectives on the health benefits of kefir in next generation sequencing era: Improvement of the host gut microbiota.

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Kim, Dong-Hyeon; Jeong, Dana; Kim, Hyunsook; Seo, Kun-Ho

2018-01-16

Kefir is a natural complex fermented milk product containing more than 50 species of probiotic bacteria and yeast, and has been demonstrated to have multiple properties conferring health benefits, including antiobesity, anti-hepatic steatosis, antioxidative, antiallergenic, antitumor, anti-inflammatory, cholesterol-lowering, constipation-alleviating, and antimicrobial properties. To better understand the underlying mechanisms of these benefits, we here review research on the effect of kefir (and kefir microorganisms) consumption to modulate the host gut microbiota. Owing to its excellent gastrointestinal resistance and colonization ability and wide ranges of microbial interaction, kefir has shown significant and wide-spectrum modulatory effects on the host gut microbiota. In particular, as a bacteria- and yeast-containing food, kefir can modulate both the gut microbiota and mycobiota. Since the association of this modulation with health benefit has only been addressed in a small number of recent studies thus far, further studies are needed to determine the precise mechanisms of the beneficial effects of kefir in relation to the modulation of the gut microbiota and mycobiota. Gaining this insight will surely help to take full advantage of this unique probiotic food.

Increasing thermal drying temperature of biosolids reduced nitrogen mineralisation and soil N2O emissions

DEFF Research Database (Denmark)

Case, Sean; Gomez Muñoz, Beatriz; Magid, Jakob

2016-01-01

Previous studies found that thermally dried biosolids contained more mineralisable organic nitrogen (N) than the raw or anaerobically digested (AD) biosolids they were derived from. However, the effect of thermal drying temperature on biosolid N availability is not well understood. This will be o......Previous studies found that thermally dried biosolids contained more mineralisable organic nitrogen (N) than the raw or anaerobically digested (AD) biosolids they were derived from. However, the effect of thermal drying temperature on biosolid N availability is not well understood...

Kefir Grains Change Fatty Acid Profile of Milk during Fermentation and Storage

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Vieira, C. P.; Álvares, T. S.; Gomes, L. S.; Torres, A. G.; Paschoalin, V. M. F.; Conte-Junior, C. A.

2015-01-01

Several studies have reported that lactic acid bacteria may increase the production of free fatty acids by lipolysis of milk fat, though no studies have been found in the literature showing the effect of kefir grains on the composition of fatty acids in milk. In this study the influence of kefir grains from different origins [Rio de Janeiro (AR), Viçosa (AV) e Lavras (AD)], different time of storage, and different fat content on the fatty acid content of cow milk after fermentation was investigated. Fatty acid composition was determined by gas chromatography. Values were considered significantly different when pkefir relatively to fermented kefir leading to possible increase of antimutagenic and anticarcinogenic potential and improvement of nutritional quality of lipids in storage milk. Only high-lipidic matrix displayed increase polyunsaturated fatty acids after fermentation. These findings open up new areas of study related to optimizing desaturase activity during fermentation in order to obtaining a fermented product with higher nutritional lipid quality. PMID:26444286

Kefir administration reduced progression of renal injury in STZ-diabetic rats by lowering oxidative stress.

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Punaro, Giovana R; Maciel, Fabiane R; Rodrigues, Adelson M; Rogero, Marcelo M; Bogsan, Cristina S B; Oliveira, Marice N; Ihara, Silvia S M; Araujo, Sergio R R; Sanches, Talita R C; Andrade, Lucia C; Higa, Elisa M S

2014-02-15

This study aimed at assessing the effects of Kefir, a probiotic fermented milk, on oxidative stress in diabetic animals. The induction of diabetes was achieved in adult male Wistar rats using streptozotocin (STZ). The animals were distributed into four groups as follows: control (CTL); control Kefir (CTLK); diabetic (DM) and diabetic Kefir (DMK). Starting on the 5th day of diabetes, Kefir was administered by daily gavage at a dose of 1.8 mL/day for 8 weeks. Before and after Kefir treatment, the rats were placed in individual metabolic cages to obtain blood and urine samples to evaluate urea, creatinine, proteinuria, nitric oxide (NO), thiobarbituric acid reactive substances (TBARS) and C-reactive protein (CRP). After sacrificing the animals, the renal cortex was removed for histology, oxidative stress and NOS evaluation. When compared to CTL rats, DM rats showed increased levels of glycemia, plasmatic urea, proteinuria, renal NO, superoxide anion, TBARS, and plasmatic CRP; also demonstrated a reduction in urinary urea, creatinine, and NO. However, DMK rats showed a significant improvement in most of these parameters. Despite the lack of differences observed in the expression of endothelial NO synthase (eNOS), the expression of inducible NO synthase (iNOS) was significantly lower in the DMK group when compared to DM rats, as assessed by Western blot analysis. Moreover, the DMK group presented a significant reduction of glycogen accumulation within the renal tubules when compared to the DM group. These results indicate that Kefir treatment may contribute to better control of glycemia and oxidative stress, which is associated with the amelioration of renal function, suggesting its use as a non-pharmacological adjuvant to delay the progression of diabetic complications. Copyright © 2014 Elsevier Inc. All rights reserved.

Análise da fermentação alcoólica do kefir em biorreator

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Renata Ferreira Miranda

2015-09-01

Full Text Available A cana-de-açúcar é a principal matéria-prima utilizada no Brasil para fermentação alcoólica. Neste trabalho, objetivou-se avaliar o efeito do kefir quanto à sua viabilidade para produção de etanol por meio da fermentação alcoólica. Os grãos de kefir se constituem de uma associação simbiótica de leveduras, bactérias ácido-láticas e bactérias ácido-acéticas tradicionalmente utilizadas para a produção de leites fermentados de baixo teor alcoólico, o que gera uma bebida associada à longevidade e considerada terapêutica. A partir de fermentação conduzida em biorreator piloto verificou-se o consumo de açúcar e produção de etanol com os grãos de kefir. O estudo realizado apresentou resultados satisfatórios para fermentação do kefir na produção de etanol.

Therapeutic effect of lyophilized, Kefir-fermented milk on constipation among persons with mental and physical disabilities.

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Maki, Rumiko; Matsukawa, Mayumi; Matsuduka, Atsuko; Hashinaga, Masahiko; Anai, Hirofumi; Yamaoka, Yoshio; Hanada, Katsuhiro; Fujii, Chieko

2017-11-06

Constipation is a serious problem for persons with mental and physical disabilities in Japan. However, prophylaxis is extremely difficult because the major causes of constipation in these individuals are related to their mental and physical disabilities. Constipation can be successfully treated with glycerol enemas (GEs) and other aperients. As constipation is a lifetime issue for these persons, dietary regimens to prevent constipation can be important. This study evaluated the probiotic effects of kefir-fermented milk for preventing constipation in 42 persons with mental and physical disabilities. The participants were administered 2 g of lyophilized kefir with each meal for 12 weeks and their bowel movements, the administration of GE and other aperients, and stool shape were recorded. The intake of kefir significantly reduced constipation, compared with the baseline status. Some individuals showed complete relief of constipation, whereas others showed no effect. Despite individual variations, consuming kefir daily could prevent constipation. © 2017 Japan Academy of Nursing Science.

Evaluation of kefir as a potential probiotic on growth performance, serum biochemistry and immune responses in broiler chicks.

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Toghyani, Majid; Mosavi, Seyed Kazem; Modaresi, Mehrdad; Landy, Nasir

2015-12-01

This experiment was conducted to evaluate the effect of milk or molasses kefir as a probiotic on growth performance, carcass traits, serum biochemistry and humoral immune responses in broiler chickens. A total of 192 one-d-old as hatched broiler chicks (Ross 308) were randomly allotted to 4 treatments, each with 4 replicate pens of 12 chicks. The following treatments were applied: 1) a basal diet (C) and normal drinking water, 2) 2% milk kefir in drinking water, 3) 2% molasses kefir in drinking water, and 4) the diet C supplemented with commercial probiotic. At d 42, eight birds per treatment were killed for determination of carcass traits. Broilers at 28 days of age were bled for measuring antibody titers against Newcastle disease virus (NDV) and avian influenza virus (AIV), at 30 days of age for antibody titers against sheep red blood cell (SRBC), and at 42 days of age for biochemical analysis. Supplementing 2% milk kefir increased body weight of broilers at 28 and 42 days of age ( P   0.05) influenced. Broilers supplemented with molasses kefir, had a significantly lower concentration of serum total cholesterol, low density lipoprotein cholesterol and elevated high density lipoprotein cholesterol at 42 days of age ( P  < 0.05). In conclusion, the results indicated that inclusion of 2% milk kefir in drinking water would improve growth performance of broiler chickens.

Evaluation of kefir as a potential probiotic on growth performance, serum biochemistry and immune responses in broiler chicks

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Majid Toghyani

2015-12-01

Full Text Available This experiment was conducted to evaluate the effect of milk or molasses kefir as a probiotic on growth performance, carcass traits, serum biochemistry and humoral immune responses in broiler chickens. A total of 192 one-d-old as hatched broiler chicks (Ross 308 were randomly allotted to 4 treatments, each with 4 replicate pens of 12 chicks. The following treatments were applied: 1 a basal diet (C and normal drinking water, 2 2% milk kefir in drinking water, 3 2% molasses kefir in drinking water, and 4 the diet C supplemented with commercial probiotic. At d 42, eight birds per treatment were killed for determination of carcass traits. Broilers at 28 days of age were bled for measuring antibody titers against Newcastle disease virus (NDV and avian influenza virus (AIV, at 30 days of age for antibody titers against sheep red blood cell (SRBC, and at 42 days of age for biochemical analysis. Supplementing 2% milk kefir increased body weight of broilers at 28 and 42 days of age (P  0.05 influenced. Broilers supplemented with molasses kefir, had a significantly lower concentration of serum total cholesterol, low density lipoprotein cholesterol and elevated high density lipoprotein cholesterol at 42 days of age (P < 0.05. In conclusion, the results indicated that inclusion of 2% milk kefir in drinking water would improve growth performance of broiler chickens.

Biosurfactant production by Pseudomonas aeruginosain kefir and fish meal.

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Kaskatepe, Banu; Yildiz, Sulhiye; Gumustas, Mehmet; Ozkan, Sibel A

2015-01-01

The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM) and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956). The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production.

Biosurfactant production by Pseudomonas aeruginosain kefir and fish meal

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Banu Kaskatepe

2015-09-01

Full Text Available The aim of this study was to increase rhamnolipid production by formulating media using kefir and fish meal for Pseudomonas aeruginosa strains isolated from different environmental resources. The strains, named as H1, SY1, and ST1, capable of rhamnolipid production were isolated from soil contaminated with wastes originating from olive and fish oil factories. Additionally, P. aeruginosa ATCC 9027 strain, which is known as rhamnolipid producer, was included in the study. Initially, rhamnolipid production by the strains was determined in Mineral Salt Medium (MSM and then in media prepared by using kefir and fish meal. The obtained rhamnolipids were purified and quantified according to Dubois et al. (1956. The quantity of rhamnolipids of ATCC, H1 and SY1 strains in kefir media were determined as 11.7 g/L, 10.8 g/L and 3.2 g/L, respectively, and in fish meal media as 12.3 g/L, 9.3 g/L and 10.3 g/L, respectively. In addition, effect of UV light exposure on rhamnolipid production was also investigated but contrary a decrease was observed. The results indicate that P. aeruginosa strains isolated from various environmental resources used in this study can be important due to their rhamnolipid yield, and fish meal, which is obtained from waste of fish, can be an alternative source in low cost rhamnolipid production.

Spray freeze-dried nanofibrillated cellulose aerogels with thermal superinsulating properties.

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Jiménez-Saelices, Clara; Seantier, Bastien; Cathala, Bernard; Grohens, Yves

2017-02-10

Nanofibrillated cellulose (NFC) aerogels were prepared by spray freeze-drying (SFD). Their structural, mechanical and thermal insulation properties were compared to those of NFC aerogels prepared by conventional freeze-drying (CFD). The purpose of this investigation is to develop superinsulating bioaerogels by reducing their pore size. Severe reduction of the aerogel pore size and skeleton architecture were observed by SEM, aerogels prepared by SFD method show a fibril skeleton morphology, which defines a mesoporous structure. BET analyses confirm the appearance of a new organization structure with pores of nanometric sizes. As a consequence, the thermal insulation properties were significantly improved for SFD materials compared to CFD aerogel, reaching values of thermal conductivity as low as 0.018W/(mK). Moreover, NFC aerogels have a thermal conductivity below that of air in ambient conditions, making them one of the best cellulose based thermal superinsulating material. Copyright © 2016 Elsevier Ltd. All rights reserved.

Kualitas Mikrobiologis dan Kimiawi Kefir Susu Kambing dengan Penambahan Lactobacillus acidophilus FNCC 0051 dan Tepung Kulit Pisang Kepok (Musa Paradisiaca

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Dwitiya Martharini

2017-03-01

Full Text Available This experiment was carried out to investigate the effect of  plantain peel flour and Lactobacillus acidophilus FNCC 0051 on the microbiological and chemical quality of goat milk kefir. Kefir was made from goat’s milk with 3 % of kefir grain (w/v and  Lactobacillus acidophilus FNCC 0051 (0, 1 and 3 % (v/v and  plantain peel flour (0, 1 and 2 % (w/v. All treatments were  incubated at room temperature (± 28.5 °C for 10 hours, until the pH dropped to 4.2-4.6.The quality of Kefir was evaluated by  microbiological analysis (total of lactic acid bacteria, probiotics  viability, total yeast and chemical analysis (pH, lactose content,  alcohol content, fat content and dietary fiber. The data of total lactic acid bacteria, probiotics viability, total yeast, pH, lactose  content, alcohol content, fat content were evaluated by analysis of variance and followed by Duncan’s New Multiple Range Test  (DMRT. Data of dietary fiber was evaluated by descriptive analysis. The research result showed that the addition of  Lactobacillus acidophilus FNCC 0051 had a significant effect (p ≤  0.05 on decreasing pH, alcohol content and increasing total lactic  acid bacteria and probiotic viability. Plantain peel flour had  significantl effect (p ≤ 0.05 on increasing alcohol content and  total lactic acid bacteria. Kefir had 9.51 log cfu mL-1 of lactic acid  bacteria total; 8.65 log cfu mL-1 of probiotic viability; 6.13 log cfu  mL-1 of total yeast; 4.85 of pH; 3.14 % of lactose content; 0.096 % of alcohol content; 5.33 % of fat content; and 10.49 % of dietary fiber. This research concluded that kefir quality for all  treatments kefir were complied with Codex Standard 234-2003  while the best treatment was the kefir with the addition of 3 %  Lactobacillus acidophilus FNCC 0051 and 1 % flour banana peel.   ABSTRAK Penelitian ini bertujuan untuk mengetahui pengaruh penambahan tepung kulit pisang dan Lactobacillus acidophilus FNCC 0051  terhadap

Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells

OpenAIRE

Takuya Yamane; Tatsuji Sakamoto; Takenori Nakagaki; Yoshihisa Nakano

2018-01-01

The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis, Lactococcus. lactis subsp. Cremoris, Lactococcus. Lactis subsp. Lactis biovar diacetylactis, Lactobacillus plantarum, Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei. In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cell...

STUDI EFFEKTIVITAS KEFIR BENING DAN MENIRAN (Philanthus niruri TERHADAP PENURUNAN KADAR GLUKOSA DARAH PADA HEWAN TIKUS WISTAR HIPERGLIKEMIA DIINDUKSI STREPTOZOTOCIN

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Judiono .

2014-09-01

were given feed refers to the AIN 93. Fasting glucose levels before and after treatment were measured by Super (Glucocard II enzimatic method. The results showed that body weight increased in all treatments, except meniran, however the increaments were not differ significantly. Changes in body weight of insulin group were 13.800 + 16.104 g, kefir treatment amounted to 13.812 + 21.294, and meniran increased about 18.394 + 16.225. Changes in blood glucose in the insulin group about -118.571+55.815 mg/dL, kefir treatment at -102.875+60.454, while meniran group -66,625+37,784. In contrast, the positive control group tended to increase glucose levels. Conclusion In vitro, plain kefir and meniran potentially lowered blood glucose levels. However, kefir showed lowered glucose level better than meniran. Futher research needs to study bio- molecular mechanisms of the decline in the future. Key words: diabetes mellitus, meniran, plain kefir, streptozotocin (STZ, hyperglycemic rat

Evaluation of quality of kefir from milk obtained from goats supplemented with a diet rich in bioactive compounds.

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Cais-Sokolińska, Dorota; Pikul, Jan; Wójtowski, Jacek; Danków, Romualda; Teichert, Joanna; Czyżak-Runowska, Grażyna; Bagnicka, Emilia

2015-04-01

The composition of bioactive components in dairy products depends on their content in raw milk and the processing conditions. The experimental material consisted of the milk of dairy goats supplemented with 120 g d(-1) per head of false flax cake. The aim of the study was to evaluate the quality of kefir produced from goat's milk with a higher content of bioactive components resulting from supplementation of the goats' diet with false flax cake. The administration of false flax cake to goats had a positive effect on the fatty acid profile of the raw milk, causing an increase in the proportion of polyunsaturated fatty acids (PUFA), including conjugated linoleic acid (CLA) and n-3 fatty acids. Their increased percentage was detected in the kefir after production as well as after storage. The processing value of the harvested milk did not differ from the qualitative characteristics of milk from goats of the control group. Increasing the proportion of bioactive components in goat's milk did not result in changes in the acidity, texture, colour, flavour, aroma or consistency of the kefir obtained. Milk and kefir obtained after the administration of false flax cake to goats contain bioactive components (PUFA including CLA, n-3 and monoenic trans fatty acids) in significant amounts. Kefir from experimental goat's milk did not differ in quality from kefir made from the milk of the control group. © 2014 Society of Chemical Industry.

Enhanced Thermal Management System for Spent Nuclear Fuel Dry Storage Canister with Hybrid Heat Pipes

International Nuclear Information System (INIS)

Jeong, Yeong Shin; Bang, In Cheol

2016-01-01

Dry storage uses the gas or air as coolant within sealed canister with neutron shielding materials. Dry storage system for spent fuel is regarded as relatively safe and emits little radioactive waste for the storage, but it showed that the storage capacity and overall safety of dry cask needs to be enhanced for the dry storage cask for LWR in Korea. For safety enhancement of dry cask, previous studies of our group firstly suggested the passive cooling system with heat pipes for LWR spent fuel dry storage metal cask. As an extension, enhanced thermal management systems for the spent fuel dry storage cask for LWR was suggested with hybrid heat pipe concept, and their performances were analyzed in thermal-hydraulic viewpoint in this paper. In this paper, hybrid heat pipe concept for dry storage cask is suggested for thermal management to enhance safety margin. Although current design of dry cask satisfies the design criteria, it cannot be assured to have long term storage period and designed lifetime. Introducing hybrid heat pipe concept to dry storage cask designed without disrupting structural integrity, it can enhance the overall safety characteristics with adequate thermal management to reduce overall temperature as well as criticality control. To evaluate thermal performance of hybrid heat pipe according to its design, CFD simulation was conducted and previous and revised design of hybrid heat pipe was compared in terms of temperature inside canister

Increase of calcium and reduction of lactose concentration in milk by treatment with kefir grains and eggshell.

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Fina, Brenda L; Brun, Lucas R; Rigalli, Alfredo

2016-01-01

Dairy products are the main source of calcium (Ca), but the loss of the consumption habit contributes to low consumption in adulthood, which leads to osteoporosis and increased fracture risk. Domestic use of kefir is straightforward and the eggshell is a natural discarded source of Ca. This paper proposes the development of an enriched Ca reduced lactose milk using eggshell and kefir. During the in vitro preparation, the pH, Ca and lactose contents were measured. Ca intestinal absorption of untreated milk and milk with kefir was compared. Finally, human volunteers consumed this dairy product and 24-h urine Ca was measured. Results showed that the beverage has lower lactose and higher Ca than untreated milk and milk with kefir. Intestinal Ca absorption was not different between both milks and an increase in urinary Ca excretion was observed in humans. This study provides a methodology to prepare at home a dairy product that could contribute to improve the Ca intake in adults.

Functional Resilience and Response to a Dietary Additive (Kefir in Models of Foregut and Hindgut Microbial Fermentation In Vitro

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Gabriel de la Fuente

2017-06-01

Full Text Available Stability in gut ecosystems is an important area of study that impacts on the use of additives and is related with several pathologies. Kefir is a fermented milk drink made with a consortium of yeast and bacteria as a fermentation starter, of which the use as additive in companion and livestock animals has increased in the last few years. To investigate the effect of kefir milk on foregut and hindgut digestive systems, an in vitro approach was followed. Either rumen fluid or horse fecal contents were used as a microbial inoculate and the inclusion of kefir (fresh, autoclaved, or pasteurized was tested. Gas production over 72 h of incubation was recorded and pH, volatile fatty acids (VFAs, lactate and ammonia concentration as well as lactic acid (LAB and acetic acid bacteria, and yeast total numbers were also measured. Both direct and indirect (by subtracting their respective blanks effects were analyzed and a multivariate analysis was performed to compare foregut and hindgut fermentation models. Addition of kefir boosted the fermentation by increasing molar concentration of VFAs and ammonia and shifting the Acetate to Propionate ratio in both models but heat processing techniques like pasteurization or autoclaving influenced the way the kefir is fermented and reacts with the present microbiota. In terms of comparison between both models, the foregut model seems to be less affected by the inclusion of Kefir than the hindgut model. In terms of variability in the response, the hindgut model appeared to be more variable than the foregut model in the way that it reacted indirectly to the addition of different types of kefir.

Functional Resilience and Response to a Dietary Additive (Kefir) in Models of Foregut and Hindgut Microbial Fermentation In Vitro.

Science.gov (United States)

de la Fuente, Gabriel; Jones, Eleanor; Jones, Shann; Newbold, Charles J

2017-01-01

Stability in gut ecosystems is an important area of study that impacts on the use of additives and is related with several pathologies. Kefir is a fermented milk drink made with a consortium of yeast and bacteria as a fermentation starter, of which the use as additive in companion and livestock animals has increased in the last few years. To investigate the effect of kefir milk on foregut and hindgut digestive systems, an in vitro approach was followed. Either rumen fluid or horse fecal contents were used as a microbial inoculate and the inclusion of kefir (fresh, autoclaved, or pasteurized) was tested. Gas production over 72 h of incubation was recorded and pH, volatile fatty acids (VFAs), lactate and ammonia concentration as well as lactic acid (LAB) and acetic acid bacteria, and yeast total numbers were also measured. Both direct and indirect (by subtracting their respective blanks) effects were analyzed and a multivariate analysis was performed to compare foregut and hindgut fermentation models. Addition of kefir boosted the fermentation by increasing molar concentration of VFAs and ammonia and shifting the Acetate to Propionate ratio in both models but heat processing techniques like pasteurization or autoclaving influenced the way the kefir is fermented and reacts with the present microbiota. In terms of comparison between both models, the foregut model seems to be less affected by the inclusion of Kefir than the hindgut model. In terms of variability in the response, the hindgut model appeared to be more variable than the foregut model in the way that it reacted indirectly to the addition of different types of kefir.

Functional Resilience and Response to a Dietary Additive (Kefir) in Models of Foregut and Hindgut Microbial Fermentation In Vitro

Science.gov (United States)

de la Fuente, Gabriel; Jones, Eleanor; Jones, Shann; Newbold, Charles J.

2017-01-01

Stability in gut ecosystems is an important area of study that impacts on the use of additives and is related with several pathologies. Kefir is a fermented milk drink made with a consortium of yeast and bacteria as a fermentation starter, of which the use as additive in companion and livestock animals has increased in the last few years. To investigate the effect of kefir milk on foregut and hindgut digestive systems, an in vitro approach was followed. Either rumen fluid or horse fecal contents were used as a microbial inoculate and the inclusion of kefir (fresh, autoclaved, or pasteurized) was tested. Gas production over 72 h of incubation was recorded and pH, volatile fatty acids (VFAs), lactate and ammonia concentration as well as lactic acid (LAB) and acetic acid bacteria, and yeast total numbers were also measured. Both direct and indirect (by subtracting their respective blanks) effects were analyzed and a multivariate analysis was performed to compare foregut and hindgut fermentation models. Addition of kefir boosted the fermentation by increasing molar concentration of VFAs and ammonia and shifting the Acetate to Propionate ratio in both models but heat processing techniques like pasteurization or autoclaving influenced the way the kefir is fermented and reacts with the present microbiota. In terms of comparison between both models, the foregut model seems to be less affected by the inclusion of Kefir than the hindgut model. In terms of variability in the response, the hindgut model appeared to be more variable than the foregut model in the way that it reacted indirectly to the addition of different types of kefir. PMID:28702019

Protective effects of the fermented milk Kefir on X-ray irradiation-induced intestinal damage in B6C3F1 mice

International Nuclear Information System (INIS)

Teruya, Kiichiro; Nakamichi, Noboru; Shirahata, Sanetaka; Myojin-Maekawa, Yuki; Shimamoto, Fumio; Watanabe, Hiromitsu; Tokumaru, Koichiro; Tokumaru, Sennosuke

2013-01-01

Gastrointestinal damage associated with radiation therapy is currently an inevitable outcome. The protective effect of Kefir was assessed for its usefulness against radiation-induced gastrointestinal damage. A Kefir supernatant was diluted by 2- or 10-fold and administered for 1 week prior to 8 Gray (Gy) X-ray irradiation at a dose rate of 2 Gy/min, with an additional 15d of administration post-irradiation. The survival rate of control mice with normal drinking water dropped to 70% on days 4 through 9 post-irradiation. On the other hand, 100% of mice in the 10- and 2-fold-diluted Kefir groups survived up to day 9 post-irradiation (p<0.05 and p<0.01, respectively). Examinations for crypt regeneration against 8, 10 and 12 Gy irradiation at a dose rate of 4 Gy/min revealed that the crypt number was significantly increased in the mice administered both diluted Kefir solutions (p<0.01 for each). Histological and immunohistochemical examinations revealed that the diluted Kefir solutions protected the crypts from radiation, and promoted crypt regeneration. In addition, lyophilized Kefir powder was found to significantly recover the testis weights (p<0.05), but had no effects on the body and spleen weights, after 8 Gy irradiation. These findings suggest that Kefir could be a promising candidate as a radiation-protective agent. (author)

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

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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.

Kefir improves fatty liver syndrome by inhibiting the lipogenesis pathway in leptin-deficient ob/ob knockout mice.

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Chen, H-L; Tung, Y-T; Tsai, C-L; Lai, C-W; Lai, Z-L; Tsai, H-C; Lin, Y-L; Wang, C-H; Chen, C-M

2014-09-01

Fatty liver disease is commonly associated with obesity, insulin resistance and diabetes. Severe fatty liver is sometimes accompanied by steatohepatitis and may lead to the development of hepatocellular carcinoma. At present, there is no effective treatment for non-alcoholic fatty liver disease (NAFLD); thus, recent investigations have focused on developing effective therapeutics to treat this condition. This study aimed to evaluate the effects of kefir on the hepatic lipid metabolism of ob/ob mice, which are commonly used to model fatty liver disease. In this study, we used leptin receptor-deficient ob/ob mice as an animal disease model of NAFLD. Six-week-old ob/ob mice were orally administered the dairy product kefir (140 mg kg(-1) of body weight (BW) per day) for 4 weeks. The data demonstrated that kefir improved fatty liver syndrome on BW, energy expenditure and basal metabolic rate by inhibiting serum glutamate oxaloacetate transaminase (GOT) and glutamate pyruvate transaminase (GPT) activities (Pkefir administration also significantly reduced the macrovesicular fat quantity in liver tissue. In addition, kefir markedly decreased the expression of the genes sterol regulatory element-binding protein 1 (SREBP1), fatty acid synthase (FAS) and acetyl-CoA carboxylase (ACC) (Pkefir improves NAFLD on BW, energy expenditure and basal metabolic rate by inhibiting the lipogenesis pathway and that kefir may have the potential for clinical application to the prevention or treatment of NAFLD.

Nutrition Quality and Microbiology of Goat Milk Kefir Fortified with Vitamin B12 and Vitamin D3 during Storage

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Dianti, EP; Anjani, G.; Afifah, DN; Rustanti, N.; Panunggal, B.

2018-02-01

Goat milk kefir fortified vitamin B12 and vitamin D3 can be an alternative to improve insulin resistance. Fortification of vitamin B12 and vitamin D3 could affect the balance of complex ecosystems of bacteria and yeasts in goat milk kefir. We analyzed the nutritional quality and microbiology of goat milk kefir during storage. This experiment was done with completely randomized design consisted of five treatments, ie storage day 0, 3rd, 6th, 9th, and 15th. Vitamin B12, vitamin D3, protein were analyzed using spectrophotometric, fat using babcock method, total lactic acid bacteria using total plate count, pH with pH meter, and viscosity using ostwald method. During 15 days in refrigerated storage, there was no significant difference (p>0,05) of vitamin B12 concentration, protein, fat, and viscosity of kefir. Storage time of the final product caused the decrease of vitamin D3 concentration between day 9 and 15 (p=0,038), pH (p=0,023), and total lactic acid of kefir (p=0,0001). Total lactic acid bacteria increased until 9 days of storage (6161 ± 1.296x107cfu / ml), but decreased to 24% on day 15 (150 ±7.78x107cfu/ml). pH kefir tends to fluctuate during storage with the highest pH value of 4,38 on day-3, and lowest 4.13 on day-9.

In vitro digestibility of goat milk and kefir with a new standardised static digestion method (INFOGEST cost action) and bioactivities of the resultant peptides.

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Nehir El, Sedef; Karakaya, Sibel; Simsek, Sebnem; Dupont, Didier; Menfaatli, Esra; Eker, Alper Tolga

2015-07-01

The hydrolysis degrees of goat milk and kefir during simulated gastrointestinal digestion and some bioactivities of the resulting peptides after fermentation and digestion were studied. A static in vitro digestion method by the COST FA1005 Action INFOGEST was used and goat milk and kefir were partially hydrolyzed during the gastric phase and had above 80% hydrolysis after duodenal digestion. There were no differences between the digestibility of goat milk and kefir (p > 0.05). Goat milk and kefir displayed about 7-fold antioxidant activity after digestion (p 0.05), however, after in vitro digestion calcium-binding capacity of the goat milk and kefir increased 2 and 5 fold, respectively (p < 0.05). Digested goat milk and kefir showed a higher dose-dependent inhibitory effect on α-amylase compared to undigested samples (p < 0.05). α-Glucosidase inhibitory activities and in vitro bile acid-binding capacities of the samples were not determined at the studied concentrations.

Short-Term Effects of Kefir-Fermented Milk Consumption on Bone Mineral Density and Bone Metabolism in a Randomized Clinical Trial of Osteoporotic Patients.

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Tu, Min-Yu; Chen, Hsiao-Ling; Tung, Yu-Tang; Kao, Chao-Chih; Hu, Fu-Chang; Chen, Chuan-Mu

2015-01-01

Milk products are good sources of calcium that may reduce bone resorption and help prevent bone loss as well as promote bone remodeling and increase bone formation. Kefir is a product made by kefir grains that degrade milk proteins into various peptides with health-promoting effects, including antithrombotic, antimicrobial and calcium-absorption enhancing bioactivities. In a controlled, parallel, double-blind intervention study over 6 months, we investigated the effects of kefir-fermented milk (1,600 mg) supplemented with calcium bicarbonate (CaCO3, 1,500 mg) and bone metabolism in 40 osteoporosis patients, and compared them with CaCO3 alone without kefir supplements. Bone turnover markers were measured in fasting blood samples collected before therapy and at 1, 3, and 6 months. Bone mineral density (BMD) values at the spine, total hip, and hip femoral neck were assessed by dual-energy x-ray absorptiometry (DXA) at baseline and at 6 months. Among patients treated with kefir-fermented milk, the relationships between baseline turnover and 6 months changes in DXA-determined BMD were significantly improved. The serum β C-terminal telopeptide of type I collagen (β-CTX) in those with T-scores > -1 patients significantly decreased after three months treatment. The formation marker serum osteocalcin (OC) turned from negative to positive after 6 months, representing the effect of kefir treatment. Serum parathyroid hormone (PTH) increased significantly after treatment with kefir, but decreased significantly in the control group. PTH may promote bone remodeling after treatment with kefir for 6 months. In this pilot study, we concluded that kefir-fermented milk therapy was associated with short-term changes in turnover and greater 6-month increases in hip BMD among osteoporotic patients. ClinicalTrials.gov NCT02361372.

Short-Term Effects of Kefir-Fermented Milk Consumption on Bone Mineral Density and Bone Metabolism in a Randomized Clinical Trial of Osteoporotic Patients.

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Min-Yu Tu

Full Text Available Milk products are good sources of calcium that may reduce bone resorption and help prevent bone loss as well as promote bone remodeling and increase bone formation. Kefir is a product made by kefir grains that degrade milk proteins into various peptides with health-promoting effects, including antithrombotic, antimicrobial and calcium-absorption enhancing bioactivities. In a controlled, parallel, double-blind intervention study over 6 months, we investigated the effects of kefir-fermented milk (1,600 mg supplemented with calcium bicarbonate (CaCO3, 1,500 mg and bone metabolism in 40 osteoporosis patients, and compared them with CaCO3 alone without kefir supplements. Bone turnover markers were measured in fasting blood samples collected before therapy and at 1, 3, and 6 months. Bone mineral density (BMD values at the spine, total hip, and hip femoral neck were assessed by dual-energy x-ray absorptiometry (DXA at baseline and at 6 months. Among patients treated with kefir-fermented milk, the relationships between baseline turnover and 6 months changes in DXA-determined BMD were significantly improved. The serum β C-terminal telopeptide of type I collagen (β-CTX in those with T-scores > -1 patients significantly decreased after three months treatment. The formation marker serum osteocalcin (OC turned from negative to positive after 6 months, representing the effect of kefir treatment. Serum parathyroid hormone (PTH increased significantly after treatment with kefir, but decreased significantly in the control group. PTH may promote bone remodeling after treatment with kefir for 6 months. In this pilot study, we concluded that kefir-fermented milk therapy was associated with short-term changes in turnover and greater 6-month increases in hip BMD among osteoporotic patients.ClinicalTrials.gov NCT02361372.

Effect of kefir and low-dose aspirin on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet.

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Kanbak, Güngör; Uzuner, Kubilay; Kuşat Ol, Kevser; Oğlakçı, Ayşegül; Kartkaya, Kazım; Şentürk, Hakan

2014-01-01

Abstract We aim to study the effect of low-dose aspirin and kefir on arterial blood pressure measurements and renal apoptosis in unhypertensive rats with 4 weeks salt diet. Forty adult male Sprague-Dawley rats were divided into five groups: control, high-salt (HS) (8.0% NaCl), HS+aspirin (10 mg/kg), HS+kefir (10.0%w/v), HS+aspirin +kefir. We measured sistolic blood pressure (SBP), mean arterial pressure (MAP), diastolic pressure, pulse pressure in the rats. Cathepsin B, L, DNA fragmentation and caspase-3 activities were determined from rat kidney tissues and rats clearance of creatinine calculated. Although HS diet increased significantly SBP, MAP, diastolic pressure, pulse pressure parameters compared the control values. They were not as high as accepted hypertension levels. When compared to HS groups, kefir groups significantly decrease Cathepsin B and DNA fragmentation levels. Caspase levels were elevated slightly in other groups according to control group. While, we also found that creatinine clearance was higher in HS+kefir and HS+low-dose aspirin than HS group. Thus, using low-dose aspirin had been approximately decreased of renal function damage. Kefir decreased renal function damage playing as Angiotensin-converting enzyme inhibitor. But, low-dose aspirin together with kefir worsened rat renal function damage. Cathepsin B might play role both apoptosis and prorenin-processing enzyme. But not caspase pathway may be involved in the present HS diet induced apoptosis. In conclusion, kefir and low-dose aspirin used independently protect renal function and renal damage induced by HS diet in rats.

Improvement of viability of probiotic bacteria, organoleptic qualities and physical characteristics in kefir using transglutaminase and xanthan.

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Sabooni, Pooria; Pourahmad, Rezvan; Adeli, Hamid Reza Mahdavi

2018-01-01

Using kefir as a probiotic food carrier has many benefits. At the same time, it is considered an appropriate product for the dairy industry. The aim of this study was to evaluate the effect of xanthan gum and transglutaminase enzyme on the viability of probiotics and the organoleptic qualities and physicochemical characteristics of kefir. Three levels of transglutaminase enzyme (50, 100 and 150 ppm), and xanthan gum (0.05%, 0.1% and 0.2%) were used. Sensory and physicochemical properties and viability of probiotic bac- teria were measured over 2 weeks of storage at 4°C. By increasing the amounts of xanthan gum and transglutaminase, the viscosity of the samples was increased and syneresis was reduced significantly (P < 0.05). The kefir sample containing 150 ppm enzyme and 0.2% gum had the highest number of probiotic bacteria. Moreover, the highest organoleptic scores were found for this sample. It can be concluded that adding 150 ppm transglutaminase and 0.2% xanthan improved the vi- ability of probiotics and the physical and organoleptic characteristics of kefir.

Experimental research of solid waste drying in the process of thermal processing

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Bukhmirov, V. V.; Kolibaba, O. B.; Gabitov, R. N.

2015-10-01

The convective drying process of municipal solid waste layer as a polydispersed multicomponent porous structure is studied. On the base of the experimental data criterial equations for calculating heat transfer and mass transfer processes in the layer, depending on the humidity of the material, the speed of the drying agent and the layer height are obtained. These solutions are used in the thermal design of reactors for the thermal processing of multicomponent organic waste.

Thermal stability study of crystalline and novel spray-dried amorphous nilotinib hydrochloride.

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Herbrink, Maikel; Vromans, Herman; Schellens, Jan; Beijnen, Jos; Nuijen, Bastiaan

2018-01-30

The thermal characteristics and the thermal degradation of crystalline and amorphous nilotinib hydrochloride (NH) were studied. The spray drying technique was successfully utilized for the amorphization of NH and was evaluated by spectroscopic techniques and differential scanning calorimetry (DSC). The ethanolic spray drying process yielded amorphous NH with a glass transition temperature (T g ) of 147°C. Thermal characterization of the amorphous phase was performed by heat capacity measurements using modulated DSC (mDSC). Thermal degradation was studied by thermogravimetric analysis (TGA). The derived thermodynamic properties of the amorphous NH indicate fragile behaviour and a low crystallization tendency. NH was found to be molecularly stable up to 193°C. After which, the thermal degradation displayed two phases. The values of the thermal degradation parameters were estimated using the Ozawa-Flynn-Wall and Friedman non-isothermal, model-free, isoconversional methods The results indicate the two phases to be single-step reactions. The examination of the physical stability of amorphous NH during storage and at elevated temperatures showed stability at 180°C for at least 5h and at 20-25°C/60% RH for at least 6 months. During these periods, no crystallization was observed. This study is the first to report the thermal characteristics of NH. Additionally, it is also the first to describe the full thermal analysis of a spray-dried amorphous drug. The thermal data may be used in the projection of future production processes and storage conditions of amorphous NH. Copyright © 2017 Elsevier B.V. All rights reserved.

Microstructure of oxides in thermal barrier coatings grown under dry/humid atmosphere

International Nuclear Information System (INIS)

Zhou Zhaohui; Guo Hongbo; Wang Juan; Abbas, Musharaf; Gong Shengkai

2011-01-01

Graphical abstract: The presence of water vapor promoted the formation of spinels in the TBC. Highlights: → Thermal barrier coatings are produced by electron beam physical vapour deposition. → Oxidation behaviour of the coatings at 1100 deg. C has been investigated in dry/humid O 2 . → Thermally grown oxides formed in the coatings are characterized. → The presence of water vapour promotes the formation of spinel in the TBCs. - Abstract: The microstructure of thermally grown oxide (TGO) in thermal barrier coatings (TBCs) oxidized under dry/humid atmosphere at 1100 deg. C has been characterized by transmission electron microscopy. A thin and continuous oxide layer is formed in the as-deposited TBCs produced by electron beam physical vapor deposition. The TGO formed in dry atmosphere consists of an outer layer of fine α-alumina, zirconia grains and an inner layer of columnar α-alumina grains. However, a small amount of spinel is observed in the TGO under humid atmosphere. The presence of water vapour promotes the formation of spinel.

Identification by PCR and evaluation of probiotic potential in yeast strains found in kefir samples in the city of Santa Maria, RS, Brazil

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Daniela CASSANEGO

2017-10-01

Full Text Available Abstract Kefir is a product elaborated from the symbiotic fermentation of different microorganisms. The Kluyveromyces and Saccharomyces genera are the major representatives of the yeasts found in kefir microbiota. The only pobiotic yeast commercialized as an oral medication, is the Saccharomyces boulardii. The present work involved the microbiological quality examination of six kefir samples in the city of Santa Maria/RS, the yeasts isolation present in the samples and the identification of them by PCR (Polymerase chain reaction. Then, their probiotic potential was evaluated by in vitro technique. After that, microbiological analysis confirmed that kefir samples were suitable for consumption once the microbiological quality was established. Nineteen yeast strains were isolated from six different kefir samples; it was identified, by PCR analysis, but only three species were identified from these microorganisms in the present article: Saccharomyces cerevisiae, Hanseniospora uvarum and Kazachstania unispora. Nevertheless, by simulating the passage of isolated strains through the gastrointestinal environment, it was observed that they could not be considered probiotics. The results indicate that, in an isolated way, the yeast presents in kefir samples, in the city of Santa Maria, RS, can´t be considered probiotics according to the tests performed.

Thermal modelling of a dry revolving vane compressor

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Ooi, K. T.; Aw, K. T.

2017-08-01

The lubricant used in compressors serves to lubricate, to seal the gaps to reduce internal leakage and to a certain extent, to cool. However, a lubricant free compressor is attractive if lubricants become a source of contaminant, or in areas where the compressor needs be placed under any orientation, such as those in military or portable computing. In this paper, a thermal model for a dry revolving vane compressor is presented. This thermal model sets out to predict the steady-state operating temperatures of the compressor components. The lumped thermal conductance method was employed. The results of the components temperature will be presented and discussed. A high potential for overheating is observed at the shaft bearings.

EVALUATION OF THERMAL EFFICIENCY OF THE TECHNOLOGICAL SCHEME OF APPLE CHIPS AND DRIED FRUITS PRODUCTION

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G. V. Kalashnikov

2014-01-01

Full Text Available The estimation of thermodynamic perfection of separate technological processes is executed at heat-moisture of handling of fruit and a line of manufacture of fruit apple chips and dried fruits. The technological scheme of a line of processing of fruits and manufactures of fruit chips on the basis of convection and the microwave-dryings suggested resource-saving. The technique is made and results of calculation of thermal expenses for various schemes of manufacture of apple chips are resulted. For the offered scheme material, thermal and power streams on the basis of balance parities of technological processes are certain. The comparative thermal production efficiency of apple chips for a base foreign variant and the offered technological scheme with the closed cycle of use of the heat-carrier and the combined convection-microwave-drying is shown. In this paper we define the thermal and energy flows for the processes of convective drying, pre-microwave drying, hydrothermal treatment and final microwave drying plant material, which are one of the main stages of the production of all kinds of fruit and vegetable concentrates, including fruit apple chips. Resource-saving ways moisture-heat of handling (hydration, blanching, drying, etc. produce raw materials in the production of food concentrates suggested a reduced water flow with a high degree of use of its potential power and microwave sources. To assess the thermal efficiency of the various processes and production schemes used as indicators of thermal efficiency and proposed value of specific heat (kJ / kg given mass productivity per unit of feedstock and translational moisture. The values of the mass fraction of the heat of material flows for the base and the proposed resource-saving production scheme fruit chips, for example, apple, based on a combination of convection-microwave drying each control surface.

[Immune regulation activity and mechanism of Tibetan Kefir exopolysaccharide fractions].

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Meng, Li; Zhang, Lanwei

2009-12-01

To investigate the effects and mechanism on immune regulation activity in mice of two Tibetan Kefir exoploysaccharides (EPS) with different molecular weight of 0.1 x 10(5) - 3 x 10(5) (fraction 1) and 1.8 x 10(3) (fraction 2). The immune regulation activity experiment was carried out in vitro based on the Functional Assessment Procedure and Test Methods of Health Food, which was issued by Ministry of Health of China. First, we treated mice subjects with EPS at doses of 40 mg/kg, 80 mg/kg, 120 mg/kg through ig. Then we detected the index of immune organs, the ability of antibody production (tested by HC50), activity of NK cell, delayed type hypersensitivity (DTH) and phagocytosis of macrophage in mice. Finally, we examined the expression of Erk protein in Macrophages by Western Blot assay. Fraction 1 could promote HC50, activity of NK cell and DTH in mice which low dose showed better. Fraction 2 could promote DTH, phagocytosis of macrophage which high dose showed better. The expression of Erk and COX-2 had the same trend with Phagocytic index. We verified the two fractions of Tibetan Kefir EPS could enhance immune functions in mice. Fraction 1 regulated immune function through NK cell and B cell while fraction 2 through macrophage cell and T cell. The effects to macrophage of Tibetan Kefir EPS in mice may realize through extra cellular signal-regulated kinase Erk pathway.

Production of fermented cheese whey-based beverage using kefir grains as starter culture: evaluation of morphological and microbial variations.

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Magalhães, Karina Teixeira; Pereira, Maria Alcina; Nicolau, Ana; Dragone, Giuliano; Domingues, Lucília; Teixeira, José António; de Almeida Silva, João Batista; Schwan, Rosane Freitas

2010-11-01

Whey valorization concerns have led to recent interest on the production of whey beverage simulating kefir. In this study, the structure and microbiota of Brazilian kefir grains and beverages obtained from milk and whole/deproteinised whey was characterized using microscopy and molecular techniques. The aim was to evaluate its stability and possible shift of probiotic bacteria to the beverages. Fluorescence staining in combination with Confocal Laser Scanning Microscopy showed distribution of yeasts in macro-clusters among the grain's matrix essentially composed of polysaccharides (kefiran) and bacteria. Denaturing gradient gel electrophoresis displayed communities included yeast affiliated to Kluyveromyces marxianus, Saccharomyces cerevisiae, Kazachatania unispora, bacteria affiliated to Lactobacillus kefiranofaciens subsp. Kefirgranum, Lactobacillus kefiranofaciens subsp. Kefiranofaciens and an uncultured bacterium also related to the genus Lactobacillus. A steady structure and dominant microbiota, including probiotic bacteria, was detected in the analyzed kefir beverages and grains. This robustness is determinant for future implementation of whey-based kefir beverages.

Kefir Grains Change Fatty Acid Profile of Milk during Fermentation and Storage.

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Vieira, C P; Álvares, T S; Gomes, L S; Torres, A G; Paschoalin, V M F; Conte-Junior, C A

2015-01-01

Several studies have reported that lactic acid bacteria may increase the production of free fatty acids by lipolysis of milk fat, though no studies have been found in the literature showing the effect of kefir grains on the composition of fatty acids in milk. In this study the influence of kefir grains from different origins [Rio de Janeiro (AR), Viçosa (AV) e Lavras (AD)], different time of storage, and different fat content on the fatty acid content of cow milk after fermentation was investigated. Fatty acid composition was determined by gas chromatography. Values were considered significantly different when p<0.05. The highest palmitic acid content, which is antimutagenic compost, was seen in AV grain (36.6g/100g fatty acids), which may have contributed to increasing the antimutagenic potential in fermented milk. Higher monounsaturated fatty acid (25.8 g/100g fatty acids) and lower saturated fatty acid (72.7 g/100g fatty acids) contents were observed in AV, when compared to other grains, due to higher Δ9-desaturase activity (0.31) that improves the nutritional quality of lipids. Higher oleic acid (25.0 g/100g fatty acids) and monounsaturated fatty acid (28.2g/100g fatty acids) and lower saturated fatty acid (67.2g/100g fatty acids) contents were found in stored kefir relatively to fermented kefir leading to possible increase of antimutagenic and anticarcinogenic potential and improvement of nutritional quality of lipids in storage milk. Only high-lipidic matrix displayed increase polyunsaturated fatty acids after fermentation. These findings open up new areas of study related to optimizing desaturase activity during fermentation in order to obtaining a fermented product with higher nutritional lipid quality.

Total phenolic content and antioxidant activities of pomegranate juice and whey based novel beverage fermented by kefir grains.

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Sabokbar, Nayereh; Khodaiyan, Faramarz

2016-01-01

Mixture of pomegranate juice and whey was evaluated as a potential substrate for production of a novel beverage by kefir grains. The effects of two different variables, fermentation, temperature (19 and 25 °C) and kefir grain amount (5 %w/v and 8 %w/v), on total phenolic content (TPC) and antioxidant activities of beverage were examined during a fermentation time of 32 h. TPC and antioxidant activities including 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging, reducing power, inhibition effect upon linoleic acid autoxidation and inhibition effect upon ascorbate autoxidation increased significantly (p < 0.05) during fermentation, but metal chelating effect showed no significant difference. The highest increases were observed when the temperature of 25 °C and kefir grain amount of 8 %w/v were applied. Results proved antioxidant activities of beverages were desirable and fermentation by kefir grains has the ability to enhance these antioxidant activities, as compared with unfermented beverage. Also pomegranate juice and whey were suitable media for producing a novel dairy-juice beverage.

Microbiological Characteristic and Nutrition Quality of Goat Milk Kefir Based on Vitamin D3 Fortification Time

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Fauziyyah, F.; Panunggal, B.; Afifah, D. N.; Rustanti, N.; Anjani, G.

2018-02-01

Goat milk kefir fortified with vitamin D3 is expected to benefit individual with insulin resistance. Different vitamin D3 fortification time allegedly effect microbiological characteristic and nutrition quality of goat milk kefir due to its microbial growth curve, thus this study aimed to analyze those parameters. This study was an experimental research. This study contains five treatments (vitamin D3 fortification at 0, 6, 12, 18, or 24 hours of fermentation) and a group of control. Total lactic acid bacteria, vitamin D3, protein level, fat contain, crude fiber, viscosity, and pH was analyzed by Total Plate Count, spectrophotometry, Bradford method, Babcock method, gravimetric analysis, Ostwald method, and pH meter respectively. Time of vitamin D3 fortification significantly effect vitamin D3 content (p=0,021), fat content (p=0,001), crude fiber (p=0,0001), viscosity (p=0,010), and total lactic acid bacteria (p=0,048). The highest vitamin D3 content was found on the group fortified at 6 hours of fermentation. All treatment groups has lower fat content and crude fiber content than control group. Total LAB in all group meet the Codex standard (≥ 107 CFU/ml). Control group and fortification group at 24 hours of fermentation have higher viscosity than other groups. There was no significant difference found in goat milk kefir protein level (p=0,262) and pH (p=0,056) despite the difference of fortification time. Vitamin D3 fortification time effect vitamin D3 content, fat content, crude fiber, viscosity, and total lactic acid bacteria of goat milk kefir, but did not effect protein content and pH of goat milk kefir.

Metallized compliant 3D microstructures for dry contact thermal conductance enhancement

Science.gov (United States)

Cui, Jin; Wang, Jicheng; Zhong, Yang; Pan, Liang; Weibel, Justin A.

2018-05-01

Microstructured three-dimensional (3D) materials can be engineered to enable new capabilities for various engineering applications; however, microfabrication of large 3D structures is typically expensive due to the conventional top-down fabrication scheme. Herein we demonstrated the use of projection micro-stereolithography and electrodeposition as cost-effective and high-throughput methods to fabricate compliant 3D microstructures as a thermal interface material (TIM). This novel TIM structure consists of an array of metallized micro-springs designed to enhance the dry contact thermal conductance between nonflat surfaces under low interface pressures (10s-100s kPa). Mechanical compliance and thermal resistance measurements confirm that this dry contact TIM can achieve conformal contact between mating surfaces with a nonflatness of approximately 5 µm under low interface pressures.

Bacteria and yeast microbiota in milk kefir grains from different Italian regions.

Science.gov (United States)

Garofalo, Cristiana; Osimani, Andrea; Milanović, Vesna; Aquilanti, Lucia; De Filippis, Francesca; Stellato, Giuseppina; Di Mauro, Simone; Turchetti, Benedetta; Buzzini, Pietro; Ercolini, Danilo; Clementi, Francesca

2015-08-01

Kefir grains are a unique symbiotic association of different microrganisms, mainly lactic acid bacteria, yeasts and occasionally acetic acid bacteria, cohabiting in a natural polysaccharide and a protein matrix. The microbial composition of kefir grains can be considered as extremely variable since it is strongly influenced by the geographical origin of the grains and by the sub-culturing method used. The aim of this study was to elucidate the bacteria and yeast species occurring in milk kefir grains collected in some Italian regions by combining the results of scanning electron microscopy analysis, viable counts on selective culture media, PCR-DGGE and pyrosequencing. The main bacterial species found was Lactobacillus kefiranofaciens while Dekkera anomala was the predominant yeast. The presence of sub-dominant species ascribed to Streptococcus thermophilus, Lactococcus lactis and Acetobacter genera was also highlighted. In addition, Lc. lactis, Enterococcus sp., Bacillus sp., Acetobacter fabarum, Acetobacter lovaniensis and Acetobacter orientalis were identified as part of the cultivable community. This work further confirms both the importance of combining culture-independent and culture-dependent approaches to study microbial diversity in food and how the combination of multiple 16S rRNA gene targets strengthens taxonomic identification using sequence-based identification approaches. Copyright © 2015 Elsevier Ltd. All rights reserved.

Microbiological and chemical characteristics of Brazilian kefir during fermentation and storage processes.

Science.gov (United States)

Leite, A M O; Leite, D C A; Del Aguila, E M; Alvares, T S; Peixoto, R S; Miguel, M A L; Silva, J T; Paschoalin, V M F

2013-07-01

The microbial community composition and chemical characteristics of a Brazilian milk kefir sample produced during its manufacturing and refrigerated storage were investigated by culture-dependent and -independent methods and HPLC. Lactococcus lactis ssp. cremoris and ssp. lactis, Leuconostoc mesenteroides, Acetobacter lovaniensis, and Saccharomyces cerevisiae were isolated, whereas the detected bands on denaturing gel gradient electrophoresis corresponded to Lactobacillus kefiranofaciens, Lactobacillus kefiri, Lactobacillus parakefiri, and S. cerevisiae. After fermentation, lactic acid bacteria were present at levels of 10 log units, whereas acetic acid bacteria and yeast were present at levels of 7.8 and 6 log units, respectively. The lactic acid bacteria and yeast counts remained constant, whereas acetic acid bacteria counts decreased to 7.2 log units during storage. From fermentation to final storage, the pH, lactose content and citric acid of the kefir beverage decreased, followed by an increase in the concentrations of glucose, galactose, ethanol, and lactic, acetic, butyric, and propionic acids. These microbiological and chemical characteristics contribute to the unique taste and aroma of kefir. This research may serve as a basis for the future industrial production of this beverage in Brazil. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Thermal analysis of cold vacuum drying of spent nuclear fuel

Energy Technology Data Exchange (ETDEWEB)

Piepho, M.G.

1998-07-20

The thermal analysis examined transient thermal and chemical behavior of the Multi canister Overpack (MCO) container for a broad range of cases that represent the Cold Vacuum Drying (CVD) processes. The cases were defined to consider both normal and off-normal operations at the CVD Facility for an MCO with Mark IV N, Reactor spent fuel in four fuel baskets and one scrap basket. This analysis provides the basis for the MCO thermal behavior at the CVD Facility for its Phase 2 Safety Analysis Report (revision 4).

Thermal stability study of crystalline and novel spray-dried amorphous nilotinib hydrochloride

NARCIS (Netherlands)

Herbrink, Maikel; Vromans, Herman; Schellens, Jan Hm; Beijnen, Jos H; Nuijen, Bastiaan

2018-01-01

The thermal characteristics and the thermal degradation of crystalline and amorphous nilotinib hydrochloride (NH) were studied. The spray drying technique was successfully utilized for the amorphization of NH and was evaluated by spectroscopic techniques and differential scanning calorimetry (DSC).

Brazilian kefir: structure, microbial communities and chemical composition

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Karina Teixeira Magalhães

2011-06-01

Full Text Available Microbial ecology and chemical composition of Brazilian kefir beverage was performed. The microorganisms associated with Brazilian kefir were investigated using a combination of phenotypic and genotypic methods. A total of 359 microbial isolates were identified. Lactic acid bacteria (60.5% were the major isolated group identified, followed by yeasts (30.6% and acetic acid bacteria (8.9%. Lactobacillus paracasei (89 isolates, Lactobacillus parabuchneri (41 isolates, Lactobacillus casei (32 isolates, Lactobacillus kefiri (31 isolates, Lactococcus lactis (24 isolates, Acetobacter lovaniensis (32 isolates, Kluyveromyces lactis (31 isolates, Kazachstania aerobia (23 isolates, Saccharomyces cerevisiae (41 isolates and Lachancea meyersii (15 isolates were the microbial species isolated. Scanning electron microscopy showed that the microbiota was dominated by bacilli (short and curved long cells growing in close association with lemon-shaped yeasts cells. During the 24 h of fermentation, the protein content increased, while lactose and fat content decreased. The concentration of lactic acid ranged from 1.4 to 17.4 mg/ml, and that of acetic acid increased from 2.1 to 2.73 mg/ml. The production of ethanol was limited, reaching a final mean value of 0.5 mg/ml.

Brazilian kefir: structure, microbial communities and chemical composition

Science.gov (United States)

Magalhães, Karina Teixeira; de Melo Pereira, Gilberto Vinícius; Campos, Cássia Roberta; Dragone, Giuliano; Schwan, Rosane Freitas

2011-01-01

Microbial ecology and chemical composition of Brazilian kefir beverage was performed. The microorganisms associated with Brazilian kefir were investigated using a combination of phenotypic and genotypic methods. A total of 359 microbial isolates were identified. Lactic acid bacteria (60.5%) were the major isolated group identified, followed by yeasts (30.6%) and acetic acid bacteria (8.9%). Lactobacillus paracasei (89 isolates), Lactobacillus parabuchneri (41 isolates), Lactobacillus casei (32 isolates), Lactobacillus kefiri (31 isolates), Lactococcus lactis (24 isolates), Acetobacter lovaniensis (32 isolates), Kluyveromyces lactis (31 isolates), Kazachstania aerobia (23 isolates), Saccharomyces cerevisiae (41 isolates) and Lachancea meyersii (15 isolates) were the microbial species isolated. Scanning electron microscopy showed that the microbiota was dominated by bacilli (short and curved long) cells growing in close association with lemon-shaped yeasts cells. During the 24 h of fermentation, the protein content increased, while lactose and fat content decreased. The concentration of lactic acid ranged from 1.4 to 17.4 mg/ml, and that of acetic acid increased from 2.1 to 2.73 mg/ml. The production of ethanol was limited, reaching a final mean value of 0.5 mg/ml. PMID:24031681

Thermal Transport Properties of Dry Spun Carbon Nanotube Sheets

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Heath E. Misak

2016-01-01

Full Text Available The thermal properties of carbon nanotube- (CNT- sheet were explored and compared to copper in this study. The CNT-sheet was made from dry spinning CNTs into a nonwoven sheet. This nonwoven CNT-sheet has anisotropic properties in in-plane and out-of-plane directions. The in-plane direction has much higher thermal conductivity than the out-of-plane direction. The in-plane thermal conductivity was found by thermal flash analysis, and the out-of-plane thermal conductivity was found by a hot disk method. The thermal irradiative properties were examined and compared to thermal transport theory. The CNT-sheet was heated in the vacuum and the temperature was measured with an IR Camera. The heat flux of CNT-sheet was compared to that of copper, and it was found that the CNT-sheet has significantly higher specific heat transfer properties compared to those of copper. CNT-sheet is a potential candidate to replace copper in thermal transport applications where weight is a primary concern such as in the automobile, aircraft, and space industries.

Thermal aspects of open sun drying of various crops

Energy Technology Data Exchange (ETDEWEB)

Jain, D.; Tiwari, G.N. [Indian Inst. of Technology, Center for Energy Studies, New Delhi (India)

2003-01-01

Open sun drying (OSD) is the most common method of crop drying in developing countries. Despite several disadvantages, it is widely practiced because it is a simple way of drying. Crop temperature, temperature around the crop, solar temperature, and rate of moisture evaporation are the important parameters in OSD. The thermal behavior of OSD of green chillies, green pea, white gram (kabuli chana), onions, potatoes, and cauliflower was studied. The heat transfer analysis which is mainly dependent on the rate of moisture transfer has also been extended during drying process. A mathematical model has been developed to predict the crop temperature, rate of moisture removal, and solar temperature for a steady state condition. The rate of moisture transfer for potato slices and cauliflower was significantly higher than that in other crops. A fair agreement was observed between predicted and experimental results with coefficient of correlations ranging from 0.8936 to 0.7520, 0.9792-0.4172, and 0.9986-0.9942 for crop temperature, temperature above the crop surface, and rate of the moisture removal during drying, respectively except potato slices. (Author)

The thermal insulation difference of clothing ensembles on the dry and perspiration manikins

International Nuclear Information System (INIS)

Xiaohong, Zhou; Chunqin, Zheng; Yingming, Qiang; Holmér, Ingvar; Gao, Chuansi; Kuklane, Kalev

2010-01-01

There are about a hundred manikin users around the world. Some of them use the manikin such as 'Walter' and 'Tore' to evaluate the comfort of clothing ensembles according to their thermal insulation and moisture resistance. A 'Walter' manikin is made of water and waterproof breathable fabric 'skin', which simulates the characteristics of human perspiration. So evaporation, condensation or sorption and desorption are always accompanied by heat transfer. A 'Tore' manikin only has dry heat exchange by conduction, radiation and convection from the manikin through clothing ensembles to environments. It is an ideal apparatus to measure the thermal insulation of the clothing ensemble and allows evaluation of thermal comfort. This paper compares thermal insulation measured with dry 'Tore' and sweating 'Walter' manikins. Clothing ensembles consisted of permeable and impermeable clothes. The results showed that the clothes covering the 'Walter' manikin absorbed the moisture evaporated from the manikin. When the moisture transferred through the permeable clothing ensembles, heat of condensation could be neglected. But it was observed that heavy condensation occurred if impermeable clothes were tested on the 'Walter' manikin. This resulted in a thermal insulation difference of clothing ensembles on the dry and perspiration manikins. The thermal insulation obtained from the 'Walter' manikin has to be modified when heavy condensation occurs. The modified equation is obtained in this study

Antibacterial Effects of a Cell-Penetrating Peptide Isolated from Kefir.

Science.gov (United States)

Miao, Jianyin; Guo, Haoxian; Chen, Feilong; Zhao, Lichao; He, Liping; Ou, Yangwen; Huang, Manman; Zhang, Yi; Guo, Baoyan; Cao, Yong; Huang, Qingrong

2016-04-27

Kefir is a traditional fermented milk beverage used throughout the world for centuries. A cell-penetrating peptide, F3, was isolated from kefir by Sephadex G-50 gel filtration, DEAE-52 ion exchange, and reverse-phase high-performance liquid chromatography. F3 was determined to be a low molecular weight peptide containing one leucine and one tyrosine with two phosphate radicals. This peptide displayed antimicrobial activity across a broad spectrum of organisms including several Gram-positive and Gram-negative bacteria as well as fungi, with minimal inhibitory concentration (MIC) values ranging from 125 to 500 μg/mL. Cellular penetration and accumulation of F3 were determined by confocal laser scanning microscopy. The peptide was able to penetrate the cellular membrane of Escherichia coli and Staphylococcus aureus. Changes in cell morphology were observed by scanning electron microscopy (SEM). The results indicate that peptide F3 may be a good candidate for use as an effective biological preservative in agriculture and the food industry.

EFFECTS OF ORAL CLEAR KEFIR PROBIOTICS ON GLYCEMIC STATUS, LIPID PEROXIDATION, ANTIOXIDATIVE PROPERTIES OF STREPTOZOTOCIN INDUCED HYPERGLYCEMIA WISTAR RATS

Directory of Open Access Journals (Sweden)

Judiono .

2014-09-01

group as a positive control (ad libitum, (4 normal animals group as a negative control (ad libitum.Blood glucose was measured by enzymatic method. Lipid peroxidation measured of MDA-TBARs by spectrophotometry. SOD and GPX Antioxidants were measured by ELISA. Catalase was measured by spectrophotometry. Probiotics Clear kefir characterization was done by microbiology identification. Data were analyzed by One Way Anova, Kruskall Walis, Duncan, Mann Whitneytest with significance level p <0.05. The result showed that clear kefir supplementation 3.6 cc / day for 30 days administration, affected on blood glucose, MDA and increased antioxidant capacity. Statistical analysis showed that there were respectively decreased of glucose (p<0.001, MDA (p<0.001. SOD antioxidant capacity was increased (<0,05, in addition GPx and Cat were also inceased(p<0,001, except in control groups. Probiotics kefir was found as many as 10(6-10(9 cfu / mL and declined to 10(5 as the decrease in pH during storage, four species of probiotics were detected, such as: Lactobacillus Sp, Sp Lactococcus and Acetobacter and Saccharomyces Sp.In conclusion, kefir supplementation significantlydecreased the blood glucose level, level of MDA and increased of antioxidants capacity. The number of probiotics declined during storage.It is interesting to identify a potential clear kefir probiotics in a pathogenesis of the β cells pancreatic repair and stability product during storage for future study. Keywords: probiotic, hyperglycemia, free radicals, lipid peroxidation, antioxidant

Whey permeate fermented with kefir grains shows antifungal effect against Fusarium graminearum.

Science.gov (United States)

Gamba, Raúl Ricardo; De Antoni, Graciela; Peláez, Angela León

2016-05-01

The objective of the work reported here was to study the antifungal capability of cell-free supernatants obtained from whey permeates after fermentation by the kefir grains CIDCA AGK1 against Fusarium graminearum growth and zearalenone (ZEA) production. The assays were performed in order to study the conidial germination inhibition -in liquid media- and the effect on fungal growth rate and the Latency phase -in solid media. We observed that fermented supernatants of pH 3·5 produced the highest percentages of inhibition of conidial germination. The dilution and, particularly, alkalinisation of them led to the gradual loss of antifungal activity. In the fungal inhibition assays on plates we found that only the highest proportion of supernatant within solid medium had significant antifungal activity, which was determined as fungicidal. There was no ZEA biosynthesis in the medium with the highest proportion of supernatant, whereas at lower concentrations, the mycotoxin production was strain-dependent. From the results obtained we concluded that kefir supernatants had antifungal activity on the F. graminearum strains investigated and inhibited mycotoxin production as well, but in a strain-dependent fashion. The present work constitutes the first report of the effect of the products obtained from the kefir-grain fermentation of whey permeates - a readily available by-product of the dairy industry - on F. graminearum germination, growth, and toxin production.

Air-Lubricated Thermal Processor For Dry Silver Film

Science.gov (United States)

Siryj, B. W.

1980-09-01

Since dry silver film is processed by heat, it may be viewed on a light table only seconds after exposure. On the other hand, wet films require both bulky chemicals and substantial time before an image can be analyzed. Processing of dry silver film, although simple in concept, is not so simple when reduced to practice. The main concern is the effect of film temperature gradients on uniformity of optical film density. RCA has developed two thermal processors, different in implementation but based on the same philosophy. Pressurized air is directed to both sides of the film to support the film and to conduct the heat to the film. Porous graphite is used as the medium through which heat and air are introduced. The initial thermal processor was designed to process 9.5-inch-wide film moving at speeds ranging from 0.0034 to 0.008 inch per second. The processor configuration was curved to match the plane generated by the laser recording beam. The second thermal processor was configured to process 5-inch-wide film moving at a continuously variable rate ranging from 0.15 to 3.5 inches per second. Due to field flattening optics used in this laser recorder, the required film processing area was plane. In addition, this processor was sectioned in the direction of film motion, giving the processor the capability of varying both temperature and effective processing area.

Mathematical model for solar drying of potato cylinders with thermal conductivity radially modulated

Science.gov (United States)

Trujillo Arredondo, Mariana

2014-05-01

A mathematical model for drying potato cylinders using solar radiation is proposed and solved analytically. The model incorporates the energy balance for the heat capacity of the potato, the radiation heat transfer from the potato toward the drying chamber and the solar radiation absorbed by the potato during the drying process. Potato cylinders are assumed to exhibit a thermal conductivity which is radially modulated. The method of the Laplace transform, with integral Bromwich and residue theorem will be applied and the analytic solutions for the temperature profiles in the potato cylinder will be derived in the form of an infinite series of Bessel functions, when the thermal conductivity is constant; and in the form of an infinite series of Heun functions, when the thermal conductivity has a linear radial modulation. All computations are performed using computer algebra, specifically Maple. It is expected that the analytical results obtained will be useful in food engineering and industry. Our results suggest some lines for future investigations such as the adoption of more general forms of radial modulation for the thermal conductivity of potato cylinders; and possible applications of other computer algebra software such as Maxima and Mathematica.

Evaluation of a potentially probiotic non-dairy beverage developed with honey and kefir grains: Fermentation kinetics and storage study.

Science.gov (United States)

Fiorda, Fernanda A; de Melo Pereira, Gilberto V; Thomaz-Soccol, Vanete; Rakshit, Sudip K; Soccol, Carlos R

2016-12-01

The aim of this work was to study the fermentation process of honey with kefir grains through a comprehensive understanding of its rheological properties, probiotic cell viability, instrumental color parameters and kinetic aspects in a batch bioreactor and during storage. The results showed that kefir grains were well adapted to bioreactor conditions, reaching high levels of cell viability (over 10 6 CFU mL -1 for total yeast and bacteria), phenolic compounds content (190 GAE/100 g) and acidification after 24 h of fermentation at 30 ℃. Colorimetric analysis showed that lightness (L*) and redness (a*) remained constant, while yellowness intensities (b*) decreased during fermentation time. After 35 days of storage, honey kefir beverage maintained its chemical characteristics and microbial viability as required to be classified as a probiotic product. The Ostwald-de-Waele (R 2  ≥ 0.98) and Herschel-Bulkley (R 2  ≥ 0.99) models can be used to predict the behavior of honey kefir beverage. The parameters analyzed in this study should be taken into account for industrial production of this novel non-dairy beverage. © The Author(s) 2016.

Effects of Microbial Transglutaminase on Physicochemical, Microbial and Sensorial Properties of Kefir Produced by Using Mixture Cow's and Soymilk.

Science.gov (United States)

Temiz, Hasan; Dağyıldız, Kübra

2017-01-01

The objective of this research was to investigate the effects microbial transglutaminase (m-TGs) on the physicochemical, microbial and sensory properties of kefir produced by using mix cow and soymilk. Kefir batches were prepared using 0, 0.5, 1 and 1.5 Units m-TGs for per g of milk protein. Adding m-TGs to milk caused an increase in the pH and viscosity and caused a decrease in titratable acidity and syneresis in the kefir samples. Total bacteria, lactobacilli and streptococci counts decreased, while yeast counts increased in all the samples during storage. Alcohols and acids compounds have increased in all the samples except in the control samples, while carbonyl compounds have decreased in all the samples during storage (1-30 d). The differences in the percentage of alcohols, carbonyl compounds and acids in total volatiles on the 1st and the 30th d of storage were observed at 8.47-23.52%, 6.94-25.46% and 59.64-63.69%, respectively. The consumer evaluation of the kefir samples showed that greater levels of acceptability were found for samples which had been added 1.5 U m-TGs for per g of milk protein.

Thermal-Hydraulic Results for the Boiling Water Reactor Dry Cask Simulator.

Energy Technology Data Exchange (ETDEWEB)

Durbin, Samuel [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Lindgren, Eric R. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2017-09-01

The thermal performance of commercial nuclear spent fuel dry storage casks is evaluated through detailed numerical analysis. These modeling efforts are completed by the vendor to demonstrate performance and regulatory compliance. The calculations are then independently verified by the Nuclear Regulatory Commission (NRC). Carefully measured data sets generated from testing of full sized casks or smaller cask analogs are widely recognized as vital for validating these models. Recent advances in dry storage cask designs have significantly increased the maximum thermal load allowed in a cask in part by increasing the efficiency of internal conduction pathways and by increasing the internal convection through greater canister helium pressure. These same canistered cask systems rely on ventilation between the canister and the overpack to convect heat away from the canister to the environment for both aboveground and belowground configurations. While several testing programs have been previously conducted, these earlier validation attempts did not capture the effects of elevated helium pressures or accurately portray the external convection of aboveground and belowground canistered dry cask systems. The purpose of this investigation was to produce validation-quality data that can be used to test the validity of the modeling presently used to determine cladding temperatures in modern vertical dry casks. These cladding temperatures are critical to evaluate cladding integrity throughout the storage cycle. To produce these data sets under well-controlled boundary conditions, the dry cask simulator (DCS) was built to study the thermal-hydraulic response of fuel under a variety of heat loads, internal vessel pressures, and external configurations. An existing electrically heated but otherwise prototypic BWR Incoloy-clad test assembly was deployed inside of a representative storage basket and cylindrical pressure vessel that represents a vertical canister system. The symmetric

Selected Lactobacillus strains isolated from sugary and milk kefir reduce Salmonella infection of epithelial cells in vitro.

Science.gov (United States)

Zavala, L; Golowczyc, M A; van Hoorde, K; Medrano, M; Huys, G; Vandamme, P; Abraham, A G

2016-09-01

The isolation of potentially probiotic strains and the subsequent study of their properties are very important steps to gain insight in the health benefits ascribed to sugary and milk kefir. The aim of the present study was to characterise fifteen Lactobacillus strains isolated from these beverages by determining some surface properties and their ability to antagonise enterocyte cell damage after Salmonella infection in vitro. Lactobacillus surface properties were determined by hydrophobicity, autoaggregation, and coaggregation assays with Salmonella. In addition, lactobacilli adhesion to Caco-2/TC-7 cells and the effect on Salmonella invasion were evaluated. Finally, the disassembly of F-actin cytoskeleton on intestinal epithelial cells was assayed in vitro when Salmonella infection was performed in the presence of selected Lactobacillus strains. Ten out of the 15 strains showed a high adhesion capacity to Caco-2/TC-7 cells. Most of the strains were hydrophilic and non-autoaggregating. Strains isolated from sugary kefir were non-coaggregating with Salmonella, while strains Lactobacillus paracasei CIDCA 83120, 83121, 83123, 83124, 8339, 83102 isolated from milk kefir were able to coaggregate after 1 h. L. paracasei CIDCA 8339 and Lactobacillus kefiri CIDCA 83102 were able to diminish Salmonella invasion to the enterocytes. An antagonistic effect on cytoskeleton disruption elicited by the pathogen was also demonstrated. Our results suggest that both strains isolated from milk kefir could be considered as appropriate probiotic candidates.

Numerical Simulation of the Thermal Performance of a Dry Storage Cask for Spent Nuclear Fuel

Directory of Open Access Journals (Sweden)

Heui-Yung Chang

2018-01-01

Full Text Available In this study, the heat flow characteristics and thermal performance of a dry storage cask were investigated via thermal flow experiments and a computational fluid dynamics (CFD simulation. The results indicate that there are many inner circulations in the flow channel of the cask (the channel width is 10 cm. These circulations affect the channel airflow efficiency, which in turn affects the heat dissipation of the dry storage cask. The daily operating temperatures at the top concrete lid and the upper locations of the concrete cask are higher than those permitted by the design specification. The installation of the salt particle collection device has a limited negative effect on the thermal dissipation performance of the dry storage cask.

The Effect of Combination Carrot Juice (Daucus carota L. and Hunkwee Flour in Manufacturing Kefir Ice Cream on Physical and Chemical Quality of Kefir Ice Cream

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Ilma Mahdiana

2017-03-01

Full Text Available The purpose of this research was to determine the best combination of carrot juice (CJ and hunkwee flour (HF on manufacturing of kefir ice cream. The method of this research was experiment with Completely Randomized Design, 4 treatments and 4 replication, the treatments were without carrot juice + HF 5% (P0, CJ 1.5% + HF 3.5% (P1, CJ 3% + HF 2% (P2, CJ 4.5% + HF 0.5% (P3, the presentage based on Ice Cream Mix (ICM. The variables measured were antioxidant activity, viscosity, total solid and organoleptic (textur, taste and aroma. The data was analized by using Analysis Of Variance (ANOVA continued by Honestly Significance Difference (HSD test. The result of this research showed that the combination of carrot juice and hunkwee flour gave highly significant difference effect (P0.05 on aroma. Conclusion: the combination of carrot juice 1.5% + hunkwee flour 3.5% (P1 in kefir ice cream gave the best result.

Kefir peptides prevent high-fructose corn syrup-induced non-alcoholic fatty liver disease in a murine model by modulation of inflammation and the JAK2 signaling pathway.

Science.gov (United States)

Chen, H L; Tsai, T C; Tsai, Y C; Liao, J W; Yen, C C; Chen, C M

2016-12-12

In recent years, people have changed their eating habits, and high-fructose-containing bubble tea has become very popular. High-fructose intake has been suggested to be a key factor that induces non-alcoholic fatty liver disease (NAFLD). Kefir, a fermented milk product composed of microbial symbionts, has demonstrated numerous biological activities, including antibacterial, antioxidant and immunostimulating effects. The present study aims to evaluate the effects of kefir peptides on high-fructose-induced hepatic steatosis and the possible molecular mechanism. An animal model of 30% high-fructose-induced NAFLD in C57BL/6J mice was established. The experiment is divided into the following six groups: (1) normal: H 2 O drinking water; (2) mock: H 2 O+30% fructose; (3) KL: low-dose kefir peptides (50 mg kg -1 )+30% fructose; (4) KM: medium-dose kefir peptides (100 mg kg -1 )+30% fructose; (5) KH: high-dose kefir peptides (150 mg kg -1 )+30% fructose; and (6) CFM: commercial fermented milk (100 mg kg -1 )+30% fructose. The results show that kefir peptides improve fatty liver syndrome by decreasing body weight, serum alanine aminotransferase, triglycerides, insulin and hepatic triglycerides, cholesterol, and free fatty acids as well as the inflammatory cytokines (TNF-α, IL-6 and IL-1β) that had been elevated in fructose-induced NAFLD mice. In addition, kefir peptides markedly increased phosphorylation of AMPK to downregulate its targeted enzymes, ACC (acetyl-CoA carboxylase) and SREBP-1c (sterol regulatory element-binding protein 1), and inhibited de novo lipogenesis. Furthermore, kefir peptides activated JAK2 to stimulate STAT3 phosphorylation, which can translocate to the nucleus, and upregulated several genes, including the CPT1 (carnitine palmitoyltransferase-1) involved in fatty acid oxidation. Our data have demonstrated that kefir peptides can improve the symptoms of NAFLD, including body weight, energy intake, inflammatory reaction and the

Kefir peptides prevent high-fructose corn syrup-induced non-alcoholic fatty liver disease in a murine model by modulation of inflammation and the JAK2 signaling pathway

Science.gov (United States)

Chen, H L; Tsai, T C; Tsai, Y C; Liao, J W; Yen, C C; Chen, C M

2016-01-01

Objective: In recent years, people have changed their eating habits, and high-fructose-containing bubble tea has become very popular. High-fructose intake has been suggested to be a key factor that induces non-alcoholic fatty liver disease (NAFLD). Kefir, a fermented milk product composed of microbial symbionts, has demonstrated numerous biological activities, including antibacterial, antioxidant and immunostimulating effects. The present study aims to evaluate the effects of kefir peptides on high-fructose-induced hepatic steatosis and the possible molecular mechanism. Results: An animal model of 30% high-fructose-induced NAFLD in C57BL/6J mice was established. The experiment is divided into the following six groups: (1) normal: H2O drinking water; (2) mock: H2O+30% fructose; (3) KL: low-dose kefir peptides (50 mg kg−1)+30% fructose; (4) KM: medium-dose kefir peptides (100 mg kg−1)+30% fructose; (5) KH: high-dose kefir peptides (150 mg kg−1)+30% fructose; and (6) CFM: commercial fermented milk (100 mg kg−1)+30% fructose. The results show that kefir peptides improve fatty liver syndrome by decreasing body weight, serum alanine aminotransferase, triglycerides, insulin and hepatic triglycerides, cholesterol, and free fatty acids as well as the inflammatory cytokines (TNF-α, IL-6 and IL-1β) that had been elevated in fructose-induced NAFLD mice. In addition, kefir peptides markedly increased phosphorylation of AMPK to downregulate its targeted enzymes, ACC (acetyl-CoA carboxylase) and SREBP-1c (sterol regulatory element-binding protein 1), and inhibited de novo lipogenesis. Furthermore, kefir peptides activated JAK2 to stimulate STAT3 phosphorylation, which can translocate to the nucleus, and upregulated several genes, including the CPT1 (carnitine palmitoyltransferase-1) involved in fatty acid oxidation. Conclusion: Our data have demonstrated that kefir peptides can improve the symptoms of NAFLD, including body weight, energy intake

Evaluation of antagonistic activity of milk fermented with kefir grains of different origins

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João Paulo Victorino Santos

2013-10-01

Full Text Available In this study, the potential of kefir grains, obtained from three different towns/cities in the Southeast Region of Brazil to inhibit the growth of the five pathogenic microorganisms was evaluated. The samples showed the growth inhibition from 42.80-69.15 for Staphylococcus aureus ATCC 6538, 30.73-59.89 for Escherichia coli ATCC 11229, 44.99-73.05 for Salmonela typhi ATCC 6539, 41.45-54.18 for Listeria monocytogenes ATCC 15313 and 70.38-86.80 for Bacillus cereus RIBO 1222-173-S4. These results indicated that the kefir grains evaluated had antagonistic activity toward the different pathogens tested. The ability to inhibit, although differently depending on the regional microbiota, indicated a potential for their use as a functional food.

Study on effectiveness of continuous solar dryer integrated with desiccant thermal storage for drying cocoa beans

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Sari Farah Dina

2015-03-01

Full Text Available The main objective is to assess effectiveness of continuous solar dryer integrated with desiccant thermal storage for drying cocoa beans. Two type of desiccants were tested, molecular sieve 13× (Na86 [(AlO286·(SiO2106]·264H2O as an adsorbent type and CaCl2 as an absorbent type. The results revealed that during sunshine hours, the maximum temperature within the drying chamber varied from 40 °C to 54 °C. In average, it was 9–12 °C higher than ambient temperature. These temperatures are very suitable for drying cocoa beans. During off-sunshine hours, humidity of air inside the drying chamber was lower than ambient because of the desiccant thermal storage. Drying times for intermittent directs sun drying, solar dryer integrated with adsorbent, and solar dryer integrated with absorbent were 55 h, 41 h, and 30 h, respectively. Specific energy consumptions for direct sun drying, solar dryer integrated with adsorbent, and solar dryer integrated with absorber were 60.4 MJ/kg moist, 18.94 MJ/kg moist, and 13.29 MJ/kg moist, respectively. The main conclusion can be drawn here is that a solar dryer integrated with desiccant thermal storage makes drying using solar energy more effective in term of drying time and specific energy consumption.

Thermal safety analysis of a dry storage cask for the Korean standard spent fuel - 16159

International Nuclear Information System (INIS)

Cha, Jeonghun; Kim, S.N.; Choi, K.W.

2009-01-01

A conceptual dry storage facility, which is based on a commercial dry storage facility, was designed for the Korea standard spent nuclear fuel (SNF) and preliminary thermal safety analysis was performed in this study. To perform the preliminary thermal analysis, a thermal analysis method was proposed. The thermal analysis method consists of 2 parts. By using the method, the surface temperature of the storage canister corresponding to the SNF clad temperature was calculated and the adequate air duct area was decided using the calculation result. The initial temperature of the facility was calculated and the fire condition and half air duct blockage were analyzed. (authors)

Effects of Starter Culture and Storage Temperature on Functional, Microbial and Sensory Characteristics of Kefir during Storage

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Tayyebeh Sarlak

2017-03-01

Full Text Available The aim of this study was to investigate the effects of starters and storage temperature (4 ºC, 25 ºC on microbiological and physicochemical properties, volatile compounds and sensory evaluation of kefir. Kefirs produced by KFA and Chr. Hansen starters were stored at 4 ºC and 25 ºC for 40 days. pH and acidity at 4 ºC did not change (p ≥ 0.05, while at 25 ºC pH and total solid decreased as well as acidity. Concentrations of acetaldehyde and ethanol increased (p < 0.05. No significant differences (p ≥ 0.05 were observed in protein and non-protein-nitrogen for both samples. Sensory evaluation revealed that storage did not affect texture and color of samples at 4 ºC. Kefir produced by Chr. Hansen starter stored at 4 ºC had the highest acceptability until 40-day storage and was preferred by the panelists.

Cna 1 spent fuel element interim dry storage system thermal analysis

International Nuclear Information System (INIS)

Hilal, R. E; Garcia, J. C; Delmastro, D. F

2006-01-01

At the moment, the Atucha I Nuclear Power Plant (Cnea-I) located in the city of Lima, has enough room to store its spent fuel (Sf) in their two pools spent fuel until about 2015.In case of life extension a spend fuel element interim dry storage system is needed.Nucleolectrica Argentina S.A. (N A-S A) and the Comision Nacional de Energia Atomica (Cnea), have proposed different interim dry storage systems.These systems have to be evaluated in order to choose one of them.The present work's objective is the thermal analysis of one dry storage alternative for the Sf element of Cna 1.In this work a simple model was developed and used to perform the thermal calculations corresponding to the system proposed by Cnea.This system considers the store of sealed containers with 37 spent fuels in concrete modules.Each one of the containers is filled in the pool houses and transported to the module in a transference cask with lead walls.Fulfill the maximum cladding temperature requirement ( [es

The influence of the dose of calcium bisglycinate on physicochemical properties, sensory analysis and texture profile of kefirs during 21 days of cold storage.

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Pawlos, Małgorzata; Znamirowska, Agata; Szajnar, Katarzyna; Kalicka, Dorota

2016-01-01

In the process of enrichment of dairy products a priority element is the proper selection of compounds that are a mineral carrier. Calcium bisglycinate is better absorbed by the body than inorganic forms of calcium. Moreover, the lactic acid which is produced in kefir fermentation and the presence of lactose have also a positive effect on the improvement of absorption of calcium. The aim of the present study was to determine the influence of the applied dose of calcium in the form of calcium bisglycinate on the physicochemical and sensory properties and texture of kefirs during 21-day period of cold storage. Processed cow milk was enriched with 0, 5, 10, 15, 20, 25 and 30 mg of calcium (for 100 g of milk), repasteurized (72°C, 1 min), cooled down (26°C), inoculated with Commercial VITAL kefir culture (Danisco, Poland) and fermented for 16 hours (26°C). The assessment of the influence of addition   of calcium bisglycinate on acidity, syneresis, texture and sensory characteristics (1-9 points) of kefirs was conducted at four fixed dates (after 1 day, 7 days, 14 days and 21 days of storage). During successive weeks of cold storage in all experimental groups there was observed a tendency to decrease general acidity. On the 1st and 7th days of cold storage reduced whey leakage was observed in kefirs enriched with 25 mg and 30 mg Ca/100 g of milk. With increasing doses of enrichment with calcium both the hardness, adhesiveness and gumminess of kefirs decreased. The applied doses of calcium did not cause changes in the sensory characteristics such as colour and consistency of the fermented beverages. Calcium bisglycinate may be used to enrich kefirs with calcium even with 30 mg of calcium in 100 g of milk without the modification of the product's parameters.

High-pressure treatment of wood - combination of mechanical and thermal drying in the ''I/D process''

Energy Technology Data Exchange (ETDEWEB)

Stahl, M. [Bundesforschungsanstalt fuer Ernaehrung, Institut fuer Verfahrenstechnik, Haid-und-Neu-Str. 9, D-76131 Karlsruhe (Germany); Bentz, M. [Institut fuer Mechanische Verfahrenstechnik und Mechanik, Universitaet Karlsruhe (T.H.), D-76128 Karlsruhe (Germany)

2004-11-01

Thermal drying of materials with internal pores is always a time-consuming and energy-intensive step within a production process. For chemical and pharmaceutical mass products and, in particular, for wood as an important raw material it is desirable to reduce the water content before thermal treatment by mechanical operations. The wood-processing industry, facing a rising stress of competition, is forced more than ever to offer high-quality products at lowest prices. Today, drying of timber is mostly done by air drying or by technical drying in kiln dryers. In any case, drying is necessary to prevent deterioration in quality by shrinkage, formation of cracks, discoloration or infestation. A new process of dewatering wood by combining mechanical and thermal means has been developed at the University of Karlsruhe. Compared to conventional drying processes, short drying times and a low residual moisture content can be achieved and, thus, energy consumption and costs can be reduced. In industrial wood drying only thermal processes (e.g., convective kiln drying, vacuum drying, etc.) have been established because so far no method has been known for removing liquid by mechanical force without significant change in wood structure. With the new I/D process chances for alternatives to conventional thermal drying or for mechanothermal applications are offered. (Abstract Copyright [2004], Wiley Periodicals, Inc.)

Effects of Kefir as a Probiotic Source on the Performance and Health of Young Dairy Calves

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Sema Satık

2017-02-01

Full Text Available The aim of this study was to investigate the effect of kefir as a probiotic on the performance and health status of calves. Thirty Holstein female calves with 3-day-old were randomly allocated to three treatment groups: Control (without any probiotic, probiotic (a commercial probiotic mixture-3 g/d/calf bacteria-based and 2 g/d/calf yeast-based and kefir (20 ml/d/calf. The calves were weaned at 56 days of age. The experiment was performed in 70 days. Treatment had no effect (P>0.05 on weaning and final body weight and starter intake. Although differences in weight gain were not significant (P>0.05, there were trend to increase by probiotic treatments during 0-14 days. Probiotic treatments tended to have a positive effect on the population of the fecal lactic acid bacteria at 14 days. The results of the study indicated that kefir as a natural probiotic in calf nutrition may be beneficial during the first weeks of life.

Use of JAR-Based Analysis for Improvement of Product Acceptance: A Case Study on Flavored Kefirs.

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Gere, Attila; Szabó, Zsófia; Pásztor-Huszár, Klára; Orbán, Csaba; Kókai, Zoltán; Sipos, László

2017-05-01

A common question of dairy product developments is the possible success of the new product. Several publications reported successful results using just-about-right (JAR) scales; although there is some debate about their advantages/disadvantages. This study highlights the limitations and opportunities of JAR scales and penalty analysis of fruit flavored kefirs. The first question is whether penalty analysis results help to improve the product and thus its overall liking (OAL)? The second question is what happens to those who rated the products "ideal" (JAR) before product development when evaluating the new products? Fruit flavored live-flora stirred-type kefir samples were formulated and evaluated by 92 consumers before and after the JAR-based product development. The OAL of two products significantly increased after product development. A new visualization tool is introduced, which shows what happens to those who rated the attribute as JAR but the attribute has been modified. A general product development scheme is also introduced for JAR-based kefir product development. © 2017 Institute of Food Technologists®.

Thermal Analysis of Cold Vacuum Drying (CVD) of Spent Nuclear Fuel (SNF)

International Nuclear Information System (INIS)

PIEPHO, M.G.

2000-01-01

The thermal analysis examined transient thermal and chemical behavior of the Multi-Canister Overpack (MCO) container for a broad range of cases that represent the Cold Vacuum Drying (CVD) processes. The cases were defined to consider both normal and off-normal operations at the CVD Facility for an MCO with N Reactor spent fuel. This analysis provides the basis for the MCO thermal behavior at the CVD Facility in support of the safety basis documentation

Mathematical model of CO2 release during milk fermentation using natural kefir grains.

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Goršek, Andreja; Ritonja, Jožef; Pečar, Darja

2018-03-12

Milk fermentation takes place in the presence of various micro-organisms, producing a variety of dairy products. The oldest of them is kefir, which is usually produced by the fermentation of milk with kefir grains. Carbon dioxide (CO 2 ), as one of the process products, also contributes to the characteristic flavor of kefir. The amount of CO 2 generated during fermentation depends on bioprocessing conditions and may change, which is not desirable at the industrial level. In this study we developed a simplified mathematical model of CO 2 release in the milk-fermentation process. An intuitive approach based on superposition and experimental analysis was used for the modeling. The chemical system studied was considered as a two-input (temperature, rotational frequency of the stirrer) one-output (CO 2 concentration) dynamic system. Based on an analysis of CO 2 release transients in the case of non-simultaneous stepwise changed input quantities, two differential equations were defined that describe the influence of the two input quantities on the output quantity. The simulation results were verified by experiments. The proposed model can be used for a comprehensive analysis of the process that is being studied and for the design and synthesis of advanced control systems, which will ensure a controlled CO 2 release at the industrial level. © 2018 Society of Chemical Industry. © 2018 Society of Chemical Industry.

Comparison of biotransformation of inorganic selenium by Lactobacillus and Saccharomyces in lactic fermentation process of yogurt and kefir.

Science.gov (United States)

Alzate, A; Fernández-Fernández, A; Pérez-Conde, M C; Gutiérrez, A M; Cámara, C

2008-09-24

The aim of the present study was to characterize, quantify, and compare the different selenium species that are produced when lactic fermentation with two different types of microorganisms, bacteria (Lactobacillus) and yeast (Saccharomyces), take place to produce yogurt and kefir, respectively, and to study the transformation process of these species as a function of time. These two dairy products were chosen for the study because they are highly consumed in different cultures. Moreover, the microorganisms present in the fermentation processes are different. While the bacteria Lactobacillus is the one responsible for yogurt fermentation, a partnership between bacteria and the yeast Saccharomyces causes kefir fermentation. A comparative study has been carried out by fermenting Se(IV) enriched milk in the presence of both types of microorganisms, where the concentration range studied was from 0.5 to 20 microg g (-1). Enzymatic extraction enabled selenium speciation profiles, obtained by anionic exchange and ion-pairing reversed phase high performance liquid chromatography (IP-RP-HPLC) with inductively coupled plasma mass spectrometry (ICP-MS) detection. Scanning electron microscopy (SEM) applied to the enriched samples showed segregated Se (0), at added concentrations higher than 5 microg g (-1). The main Se species formed depended on the type of microorganism involved in the fermentation process, SeCys 2 and MeSeCys being the main species generated in yogurt and SeMet in kefir. The results obtained are different for both kinds of samples. Lactic fermentation for yogurt produced an increment in selenocystine (SeCys 2) and Se-methylselenocysteine (MeSeCys), while fermentation to produce kefir also incremented the selenomethionine (SeMet) concentration. The Se species are stable for at least 10 and 15 days for kefir and yogurt, respectively. After this period, selenocystine concentration decreased, and the concentration of Se-methylselenocysteine was found to

Basic Considerations for Dry Storage of Spent Nuclear Fuels and Revisited CFD Thermal Analysis on the Concrete Cask

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Noh, Jae Soo [ACT Co. Ltd., Daejeon (Korea, Republic of); Park, Younwon; Song, Sub Lee [BEES Inc., Daejeon (Korea, Republic of); Kim, Hyeun Min [KAIST, Daejeon (Korea, Republic of)

2016-10-15

The integrity of storage facility and also of the spent nuclear fuel itself is considered very important. Storage casks can be located in a designated area on a site or in a designated storage building. A number of different designs for dry storage have been developed and used in different countries. Dry storage system was classified into two categories by IAEA. One is container including cask and silo, the other one is vault. However, there is various way of categorization for dry storage system. Dry silo and cask are usually classified separately, so the dry storage system can be classified into three different types. Furthermore, dry cask storage can be categorized into two types based on the type of the materials, concrete cask and metal cask. In this paper, the design characteristics of dry storage cask are introduced and computational fluid dynamics (CFD) based thermal analysis for concrete cask is revisited. Basic principles for dry storage cask design were described. Based on that, thermal analysis of concrete dry cask was introduced from the study of H. M. Kim et al. From the CFD calculation, the temperature of concrete wall was maintained under the safety criteria. From this fundamental analysis, further investigations are expected. For example, thermal analysis on the metal cask, thermal analysis on horizontally laid spent nuclear fuel assemblies for transportation concerns, and investigations on better performance of natural air circulation in dry cask can be promising candidates.

Basic Considerations for Dry Storage of Spent Nuclear Fuels and Revisited CFD Thermal Analysis on the Concrete Cask

International Nuclear Information System (INIS)

Noh, Jae Soo; Park, Younwon; Song, Sub Lee; Kim, Hyeun Min

2016-01-01

The integrity of storage facility and also of the spent nuclear fuel itself is considered very important. Storage casks can be located in a designated area on a site or in a designated storage building. A number of different designs for dry storage have been developed and used in different countries. Dry storage system was classified into two categories by IAEA. One is container including cask and silo, the other one is vault. However, there is various way of categorization for dry storage system. Dry silo and cask are usually classified separately, so the dry storage system can be classified into three different types. Furthermore, dry cask storage can be categorized into two types based on the type of the materials, concrete cask and metal cask. In this paper, the design characteristics of dry storage cask are introduced and computational fluid dynamics (CFD) based thermal analysis for concrete cask is revisited. Basic principles for dry storage cask design were described. Based on that, thermal analysis of concrete dry cask was introduced from the study of H. M. Kim et al. From the CFD calculation, the temperature of concrete wall was maintained under the safety criteria. From this fundamental analysis, further investigations are expected. For example, thermal analysis on the metal cask, thermal analysis on horizontally laid spent nuclear fuel assemblies for transportation concerns, and investigations on better performance of natural air circulation in dry cask can be promising candidates

Effect of deposition temperature and thermal annealing on the dry etch rate of a-C: H films for the dry etch hard process of semiconductor devices

International Nuclear Information System (INIS)

Lee, Seung Moo; Won, Jaihyung; Yim, Soyoung; Park, Se Jun; Choi, Jongsik; Kim, Jeongtae; Lee, Hyeondeok; Byun, Dongjin

2012-01-01

The effect of deposition and thermal annealing temperatures on the dry etch rate of a-C:H films was investigated to increase our fundamental understanding of the relationship between thermal annealing and dry etch rate and to obtain a low dry etch rate hard mask. The hydrocarbon contents and hydrogen concentration were decreased with increasing deposition and annealing temperatures. The I(D)/I(G) intensity ratio and extinction coefficient of the a-C:H films were increased with increasing deposition and annealing temperatures because of the increase of sp 2 bonds in the a-C:H films. There was no relationship between the density of the unpaired electrons and the deposition temperature, or between the density of the unpaired electrons and the annealing temperature. However, the thermally annealed a-C:H films had fewer unpaired electrons compared with the as-deposited ones. Transmission electron microscopy analysis showed the absence of any crystallographic change after thermal annealing. The density of the as-deposited films was increased with increasing deposition temperature. The density of the 600 °C annealed a-C:H films deposited under 450 °C was decreased but at 550 °C was increased, and the density of all 800 °C annealed films was increased. The dry etch rate of the as-deposited a-C:H films was negatively correlated with the deposition temperature. The dry etch rate of the 600 °C annealed a-C:H films deposited at 350 °C and 450 °C was faster than that of the as-deposited film and that of the 800 °C annealed a-C:H films deposited at 350 °C and 450 °C was 17% faster than that of the as-deposited film. However, the dry etch rate of the 550 °C deposited a-C:H film was decreased after annealing at 600 °C and 800 °C. The dry etch rate of the as-deposited films was decreased with increasing density but that of the annealed a-C:H films was not. These results indicated that the dry etch rate of a-C:H films for dry etch hard masks can be further decreased by

Kefir consumption does not alter plasma lipid levels or cholesterol fractional synthesis rates relative to milk in hyperlipidemic men: a randomized controlled trial [ISRCTN10820810

Science.gov (United States)

St-Onge, Marie-Pierre; Farnworth, Edward R; Savard, Tony; Chabot, Denise; Mafu, Akier; Jones, Peter JH

2002-01-01

Background Fermented milk products have been shown to affect serum cholesterol concentrations in humans. Kefir, a fermented milk product, has been traditionally consumed for its potential health benefits but has to date not been studied for its hypocholesterolemic properties. Methods Thirteen healthy mildly hypercholesterolemic male subjects consumed a dairy supplement in randomized crossover trial for 2 periods of 4 wk each. Subjects were blinded to the dairy supplement consumed. Blood samples were collected at baseline and after 4 wk of supplementation for measurement of plasma total, low-density lipoprotein, and high-density lipoprotein cholesterol and triglyceride concentrations, as well as fatty acid profile and cholesterol synthesis rate. Fecal samples were collected at baseline and after 2 and 4 wk of supplementation for determination of fecal short chain fatty acid level and bacterial content. Results Kefir had no effect on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglyceride concentrations nor on cholesterol fractional synthesis rates after 4 wk of supplementation. No significant change on plasma fatty acid levels was observed with diet. However, both kefir and milk increased (p < 0.05) fecal isobutyric, isovaleric and propionic acids as well as the total amount of fecal short chain fatty acids. Kefir supplementation resulted in increased fecal bacterial content in the majority of the subjects. Conclusions Since kefir consumption did not result in lowered plasma lipid concentrations, the results of this study do not support consumption of kefir as a cholesterol-lowering agent. PMID:11825344

Identification and assessment of kefir yeast potential for sugar/ethanol-resistance

Science.gov (United States)

Miguel, M.G.C.P.; Cardoso, P.G.; Magalhães-Guedes, K.T.; Schwan, R.F.

2013-01-01

Biochemical and molecular analysis was used for identification of different kefir yeasts species from Brazil, Canada and the United States of America. The sugar/ethanol-resistant activity of the yeasts was evaluated. Saccharomyces cerevisiae and Kluyveromyces marxianus had the highest growth rates, suggesting biotechnological applications possible for these strains. PMID:24159292

Kefir alleviates obesity and hepatic steatosis in high-fat diet-fed mice by modulation of gut microbiota and mycobiota: targeted and untargeted community analysis with correlation of biomarkers.

Science.gov (United States)

Kim, Dong-Hyeon; Kim, Hyunsook; Jeong, Dana; Kang, Il-Byeong; Chon, Jung-Whan; Kim, Hong-Seok; Song, Kwang-Young; Seo, Kun-Ho

2017-06-01

Kefir is a probiotic beverage containing over 50 species of lactic acid bacteria and yeast. In this study, the anti-obesity and anti-non-alcoholic fatty liver disease (NAFLD) effects of kefir were comprehensively addressed along with targeted and untargeted community analysis of the fecal microbiota in a high-fat diet (HFD)-induced obese mouse model. HFD-fed C57BL/6 mice were orally administrated either kefir or milk (control) once a day for 12 weeks, and body and organ weight, fecal microbiota and mycobiota, histopathology, blood cholesterol and cytokines and gene expressions were analyzed. Compared to the control, mice in the kefir group exhibited a significantly lower body weight (34.18 g vs. 40.24 g; p=0.00004) and histopathological liver lesion score (1.13 vs. 3.25; p=0.002). Remarkably, the kefir-fed mice also harbored more Lactobacillus/Lactococcus (7.01 vs. 6.32 log CFU/g), total yeast (6.07 vs. 5.01 log CFU/g) and Candida (5.56 vs. 3.88 log CFU/g). Kefir administration also up-regulated genes related to fatty acid oxidation, PPARα and AOX, in both the liver and adipose tissue (PPARα, 2.95- and 2.15-fold; AOX, 1.89- and 1.9-fold, respectively). The plasma concentration of IL-6, a proinflammatory marker, was significantly reduced following kefir consumption (50.39 pg/ml vs. 111.78 pg/ml; p=0.03). Strikingly, the populations of Lactobacillus/Lactococcus, total yeast and Candida were strongly correlated with PPARα gene expression in adipose and hepatic tissue (r=0.599, 0.580 and 0.562, respectively). These data suggest that kefir consumption modulates gut microbiota and mycobiota in HFD-fed mice, which prevents obesity and NAFLD via promoting fatty acid oxidation. Copyright © 2017 Elsevier Inc. All rights reserved.

The benefits of soluble non-bacterial fraction of kefir on blood pressure and cardiac hypertrophy in hypertensive rats are mediated by an increase in baroreflex sensitivity and decrease in angiotensin-converting enzyme activity.

Science.gov (United States)

Brasil, Girlandia Alexandre; Silva-Cutini, Mirian de Almeida; Moraes, Flávia de Souza Andrade; Pereira, Thiago de Melo Costa; Vasquez, Elisardo Corral; Lenz, Dominik; Bissoli, Nazaré Souza; Endringer, Denise Coutinho; de Lima, Ewelyne Miranda; Biancardi, Vinícia Campana; Maia, June Ferreira; de Andrade, Tadeu Uggere

We aimed to evaluate whether long-term treatment with the soluble non-bacterial fraction of kefir affects mean arterial pressure (MAP) and cardiac hypertrophy through the modulation of baroreflex sensitivity, ACE activity, and the inflammatory-to-anti-inflammatory cytokine ratio in spontaneously hypertensive rats (SHRs). SHRs were treated with the soluble non-bacterial kefir fraction (SHR-kefir) or with kefir vehicle (SHR-soluble fraction of milk). Normotensive control Wistar Kyoto animals received the soluble fraction of milk. All treatments were administered by gavage (0.3 mL/100g/body weight), once daily for eight weeks. At the end, after basal MAP and Heart Rate (HT) measurement, barorreflex sensitivity was evaluated through in bolus administrations of sodium nitroprusside and phenylephrine (AP 50 [arterial pressure 50%], the lower plateau, and HR range were measured). ACE activity and cytokines (TNF-α and IL-10) were evaluated by ELISA. Cardiac hypertrophy was analysed morphometrically. Compared to SHR control, SHR-kefir exhibited a significant decrease in both MAP (SHR: 184 ± 5; SHR-Kefir: 142 ± 8 mmHg), and HR (SHR: 360 ± 10; SHR-kefir: 310 ± 14 bpm). The non-bacterial fraction of kefir also reduced cardiac hypertrophy, TNF-α-to-IL10 ratio, and ACE activity in SHRs. SHR-kefir baroreflex sensitivity, resulted in a partial but significant recovery of baroreflex gain, as demonstrated by improvements in AP 50 , the lower plateau, and HR range. In summary, our results indicate that long-term administration of the non-bacterial fraction of kefir promotes a significant decrease in both MAP and HR, by improving baroreflex, and reduces cardiac hypertrophy in SHRs, likely via ACE inhibition, and reduction of the TNF-α-to-IL10 ratio. Copyright © 2018 Elsevier Inc. All rights reserved.

Draft Genome Sequence of Corynebacterium kefirresidentii SB, Isolated from Kefir.

Science.gov (United States)

Blasche, Sonja; Kim, Yongkyu; Patil, Kiran R

2017-09-14

The genus Corynebacterium includes Gram-positive species with a high G+C content. We report here a novel species, Corynebacterium kefirresidentii SB, isolated from kefir grains collected in Germany. Its draft genome sequence was remarkably dissimilar (average nucleotide identity, 76.54%) to those of other Corynebacterium spp., confirming that this is a unique novel species. Copyright © 2017 Blasche et al.

Outcomes of Thermal Pulsation Treatment for Dry Eye Syndrome in Patients With Sjogren Disease.

Science.gov (United States)

Godin, Morgan R; Stinnett, Sandra S; Gupta, Preeya K

2018-04-26

To evaluate the clinical outcomes of thermal pulsation treatment in patients with meibomian gland dysfunction (MGD) and dry eye secondary to Sjogren disease. Twenty-four eyes from 13 patients with previously diagnosed Sjogren disease who presented to our institution with dry eye symptoms and had thermal pulsation treatment were prospectively followed up. Patients underwent comprehensive slit-lamp examination, including MGD grading, gland oil flow, corneal and conjunctival staining scores, and tear break-up time (TBUT). Tear osmolarity was tested before and after treatment. The average patient age was 62.4 years (range, 31-78 yrs); 12 were women and 1 a man. The average meibomian gland oil flow score showed an increase from pretreatment 0.71 to 1.75 at 1 year posttreatment (range 9-15 months) (P = 0.001). The average corneal staining score decreased from a pretreatment grade of 1.04 to a posttreatment grade of 0.36 (P dry eye disease in patients with Sjogren disease and should not be overlooked when considering treatment options. Thermal pulsation is a therapeutic option for patients with Sjogren disease who have MGD and dry eye symptoms. After a single treatment, patients exhibited increased oil flow and tear break-up time with an associated decrease in corneal and conjunctival staining.

Effects of Microbial Transglutaminase on Physicochemical, Microbial and Sensorial Properties of Kefir Produced by Using Mixture Cow’s and Soymilk

Science.gov (United States)

2017-01-01

The objective of this research was to investigate the effects microbial transglutaminase (m-TGs) on the physicochemical, microbial and sensory properties of kefir produced by using mix cow and soymilk. Kefir batches were prepared using 0, 0.5, 1 and 1.5 Units m-TGs for per g of milk protein. Adding m-TGs to milk caused an increase in the pH and viscosity and caused a decrease in titratable acidity and syneresis in the kefir samples. Total bacteria, lactobacilli and streptococci counts decreased, while yeast counts increased in all the samples during storage. Alcohols and acids compounds have increased in all the samples except in the control samples, while carbonyl compounds have decreased in all the samples during storage (1-30 d). The differences in the percentage of alcohols, carbonyl compounds and acids in total volatiles on the 1st and the 30th d of storage were observed at 8.47-23.52%, 6.94-25.46% and 59.64-63.69%, respectively. The consumer evaluation of the kefir samples showed that greater levels of acceptability were found for samples which had been added 1.5 U m-TGs for per g of milk protein. PMID:28943774

Analog kefir production with a low phenylalanine for Phenylketonuria

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Amir Yari

2017-06-01

Full Text Available Phenylketonuria (PKU is one of the most prevalent types of hereditary metabolic disorders which is caused due to an absence or reduction of the activity of the Phenylalanine hydroxylase enzyme in the liver which in turn, inhibits the transformation of phenylalanine (Phe to tyrosine. In clinical terms, this disorder is displayed with severe, permanent and irreversible mental retardation. This research was aimed at development of a highly nutrient and acceptable suitable analogue Kefir drink for these patients. The mentioned drink is based on milk permeate, cream powder and includes glycomacropeptide (GMP as a source of protein, starter as a fermentation source, the trance glutamines (TG enzyme, dough stabilizer and modified corn starch as tissue maker, salt and water. The GMP used in this analogue drink is intended for enrichment of the product and therefore it was added by 3% to one formula. The aforementioned sample had a lower calculated amount of pH and alcohol percentage in comparison with the 16 samples which did not have GMP. The results of this study showed that the analog kefir has a low level of phenylalanine (30.40 mg/100g and in that regard, it can be considered to be useful for patients with PKU.

The Study of the Probiotic Potential of the Beneficial Bacteria Isolated from Kefir Grains

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Englerová K.

2017-03-01

Full Text Available The aim of this study was to identify beneficial bacteria with probiotic potential from kefir grains. The lactobacilli isolated from kefir grains were characterised as: Lactobacillus plantarum, Lactobacillus paraplantarum, Lactobacillus paracasei, and Lactobacillus kefiri. The strains Lb. plantarum 1Ž, Lb. paraplantarum S10, and Lb. paracasei 2Ž tolerated better the test gastric juice at pH 2 and 2.6 during 120 min of incubation in comparison with the strains Lb. kefiri. On the other hand, the strains Lb. kefiri were resistant to 0.3 % bile acid salts. The Lb. paracasei 2Ž showed the significantly highest survival (P < 0.001 at pH 2 in comparison with all other strains tested and was also able to tolerate 0.3 % concentration of the bile salts. All strains produced medium to strong biofilms on abiotic surfaces and inhibited the growth of selected potential pathogens with varying intensity. All kefir isolates were susceptible to the antibiotics tested and exhibited positive β-galactosidase activity with the exception of Lb. paracasei 2Ž which did not show any activity of undesirable enzymes, such as β-glucosidase and β-glucuronidase. Additional testing and validation of the biological properties and safety of the strain Lb. paracasei 2Ž under in vivo conditions are needed to confirm the prospective use of this strain in practice.

Níveis séricos de cortisol basal em ratos sob tratamento oral com kefir

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Bárbara de Oliveira Prado

2013-08-01

Full Text Available A via de metabolismo do kefir ainda é desconhecida em muitas funções, pois há poucos estudos que a evidenciam. Assim a proposta do presente estudo é avaliar o efeito do kefir sobre os níveis séricos de cortisol basal. Um Estudo experimental em que foram utilizados 60 ratos, machos, wistar, peso de 180±30g, sendo 20 animais de experimento por 07, 14 e 21dias, divididos em Kefir 20g/200ml (GK; Dexametasona 0,125mg/kg (GD; Ranitidina 0,85mg/kg (GR; Omeprazol 0,68mg/kg (GO; Controle água ad libitum (GCO. Os resultados foram avaliados pelo Software BioEstat 5.0, e para verificação do nível de significância (α<5% usou-se a ANOVA com o teste Tukey-kramer e Bartlett’s test. Os resultados obtidos revelaram que o cortisol basal (µg/dL do sangue de 60 ratos (Rattus norvegicus submetidos ao tratamento, com D7 (P<0.05, evidenciou no GR uma média representativa sobre os demais grupos com 2.2075 μg/dl, e desvio padrão (SD de 0.4329 μg/dl. Já em D14, as alterações evidenciadas foram relativamente mínimas e pouco representativas, com D21 quando relacionado o GO e GR (P<0.01, ao que tange a relação entre o GK e o GD apresentou diferenças significativas (P< 0,001. A média no GK foi de 3,4 μg/dl com um SD de 0,3238 μg/dl sobre os demais grupos experimentais, o GD apresentou níveis muito baixos de cortisol com 0,0275μg/dl e o SD de 0,009574 μg/dl. Conclui-se que o Kefir, quando consumido em doses contínuas e diariamente, repercutiu na elevação dos níveis séricos de cortisol. Não foi possível estabelecer a via de mecanismo que tenha contribuído para tal, entretanto, esse aumento ocorreu sem que os animais sofressem qualquer tipo de dano, ou seja, os animais submetidos ao tratamento com kefir mostraram-se mais vistosos, pelagem firme e com brilho, esboçando aspecto saudável.

Analog kefir production with a low phenylalanine for Phenylketonuria

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Amir Yari; Yousef Ramezan

2017-01-01

Phenylketonuria (PKU) is one of the most prevalent types of hereditary metabolic disorders which is caused due to an absence or reduction of the activity of the Phenylalanine hydroxylase enzyme in the liver which in turn, inhibits the transformation of phenylalanine (Phe) to tyrosine. In clinical terms, this disorder is displayed with severe, permanent and irreversible mental retardation. This research was aimed at development of a highly nutrient and acceptable suitable analogue Kefir drink ...

Kefir consumption does not alter plasma lipid levels or cholesterol fractional synthesis rates relative to milk in hyperlipidemic men: a randomized controlled trial [ISRCTN10820810

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Mafu Akier

2002-01-01

Full Text Available Abstract Background Fermented milk products have been shown to affect serum cholesterol concentrations in humans. Kefir, a fermented milk product, has been traditionally consumed for its potential health benefits but has to date not been studied for its hypocholesterolemic properties. Methods Thirteen healthy mildly hypercholesterolemic male subjects consumed a dairy supplement in randomized crossover trial for 2 periods of 4 wk each. Subjects were blinded to the dairy supplement consumed. Blood samples were collected at baseline and after 4 wk of supplementation for measurement of plasma total, low-density lipoprotein, and high-density lipoprotein cholesterol and triglyceride concentrations, as well as fatty acid profile and cholesterol synthesis rate. Fecal samples were collected at baseline and after 2 and 4 wk of supplementation for determination of fecal short chain fatty acid level and bacterial content. Results Kefir had no effect on total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglyceride concentrations nor on cholesterol fractional synthesis rates after 4 wk of supplementation. No significant change on plasma fatty acid levels was observed with diet. However, both kefir and milk increased (p Conclusions Since kefir consumption did not result in lowered plasma lipid concentrations, the results of this study do not support consumption of kefir as a cholesterol-lowering agent.

Brazilian Kefir-Fermented Sheep's Milk, a Source of Antimicrobial and Antioxidant Peptides.

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de Lima, Meire Dos Santos Falcão; da Silva, Roberto Afonso; da Silva, Milena Fernandes; da Silva, Paulo Alberto Bezerra; Costa, Romero Marcos Pedrosa Brandão; Teixeira, José António Couto; Porto, Ana Lúcia Figueiredo; Cavalcanti, Maria Taciana Holanda

2017-12-28

Fermented milks are a source of bioactive peptides and may be considered as functional foods. Among these, sheep's milk fermented with kefir has not been widely studied and its most relevant properties need to be more thoroughly characterized. This research study is set out to investigate and evaluate the antioxidant and antimicrobial properties of peptides from fermented sheep's milk in Brazil when produced by using kefir. For this, the chemical and microbiological composition of the sheep's milk before and after the fermentation was evaluated. The changes in the fermented milk and the peptides extracted before the fermentation and in the fermented milk during its shelf life were verified. The antimicrobial and antioxidant activities of the peptides from the fermented milk were evaluated and identified according to the literature. The physicochemical properties and mineral profile of the fermented milk were like those of fresh milk. The peptide extract presented antimicrobial activity and it was detected that 13 of the 46 peptides were able to inhibit the growth of pathogenic microorganisms. A high antioxidant activity was observed in the peptides extracted from fermented milk (3.125 mg/mL) on the 28th day of storage. Two fractions displayed efficient radical scavenging properties by DPPH and ABTS methods. At least 11 peptides distributed in the different fractions were identified by tandem mass spectrometry. This sheep's milk fermented by Brazilian kefir grains, which has antioxidant and antimicrobial activities and probiotic microorganisms, is a good candidate for further investigation as a source for bioactive peptides. The fermentation process was thus a means by which to produce potential bioactive peptides.

Adsorption of aflatoxin B1, zearalenone and ochratoxin A by microorganisms isolated from Kefir grains.

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Taheur, Fadia Ben; Fedhila, Kais; Chaieb, Kamel; Kouidhi, Bochra; Bakhrouf, Amina; Abrunhosa, Luís

2017-06-19

A strategy to reduce the deleterious effects of mycotoxins is to use dietary supplements that contain microorganisms that bind mycotoxins and decrease their gastrointestinal absorption. Novel strains were isolated from a Kefir culture and assessed for their mycotoxin adsorption and biotransformation ability. The most active strains were identified using DNA sequencing, and the stability of microorganism/mycotoxin complexes was evaluated using buffer solutions to simulate the pH conditions in the gastrointestinal tract. Our results showed that the microorganism consortium of Kefir grains adsorbed 82 to 100% of aflatoxin B1 (AFB1), zearalenone (ZEA) and ochratoxin A (OTA) when cultivated in milk. The main strains that were capable of mycotoxin adsorption were identified as Lactobacillus kefiri, Kazachstania servazzii and Acetobacter syzygii. The strain L. kefiri KFLM3 was the most active, adsorbing 80 to 100% of the studied mycotoxins when cultivated in milk. Nonetheless, the strain K. servazzii KFGY7 retained more mycotoxin after the desorption experiments (65, 69 and 67% for AFB1, OTA and ZEA, respectively). These findings suggest that Kefir consumption may help to reduce gastrointestinal absorption of these mycotoxins and consequently reduce their toxic effects. The isolated strains may be of interest for the development of fermented dairy products for human consumption that have a new probiotic characteristic, the adsorption of mycotoxins. Copyright © 2017 Elsevier B.V. All rights reserved.

Kefir drink leads to a similar weight loss, compared with milk, in a dairy-rich non-energy-restricted diet in overweight or obese premenopausal women: a randomized controlled trial.

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Fathi, Yasamin; Faghih, Shiva; Zibaeenezhad, Mohammad Javad; Tabatabaei, Sayed Hamid Reza

2016-02-01

Controversy exists regarding whether increasing dairy intake without energy restriction would lead to weight loss. We aimed to compare the potential weight-reducing effects of kefir drink (a probiotic dairy product) and milk in a dairy-rich non-energy-restricted diet in overweight or obese premenopausal women. One hundred and forty-four subjects were assessed for eligibility in this single-center, multi-arm, parallel-group, randomized controlled trial. Of these, seventy-five eligible women aged 25-45 years were randomly assigned to three groups, labeled as control, milk, and kefir, to receive an outpatient dietary regimen for 8 weeks. Subjects in the control group received a diet providing a maintenance level of energy intake, containing 2 servings/day of low-fat dairy products, while those in the milk and kefir groups received a weight maintenance diet, containing 2 additional servings/day (a total of 4 servings/day) of dairy products from low-fat milk or commercial kefir drink, respectively. Anthropometric outcomes including weight, body mass index (BMI), and waist circumference (WC) were measured every 2 weeks. Fifty-eight subjects completed the study. Using analysis of covariance models in the intention-to-treat population (n = 75), we found that at 8 weeks, subjects in the kefir and milk groups had significantly greater reductions in weight, BMI, and WC compared to those in the control group (all p < 0.01). However, no such significant differences were found between the kefir and milk groups. Kefir drink leads to a similar weight loss, compared with milk, in a dairy-rich non-energy-restricted diet in overweight or obese premenopausal women. However, further studies are warranted.

Atividade antiinflamatória de carboidrato produzido por fermentação aquosa de grãos de quefir Anti-inflammatory activity of carbohydrate produced from aqueous fermentation of kefir

OpenAIRE

Maria E. C. Moreira; Marcelo H. Santos; Ivan O. Pereira; Vany Ferraz; Luiz C. A. Barbosa; José M. Schneedorf

2008-01-01

Kefir, a symbiont microorganism suspension, presents benefic effects to health. Some kefir grains were cultivated in brown sugar, allowing to isolate a substance named CSQ. This was evaluated on a biologic essay of mouse foot edema, presenting an inhibitory activity of 30+4 % against carrageenan after the stimulus. It was observed that a cultivation mean containing sucrose, and not the milky mean, lead to the production of different sugar polymeric chains of kefir. The results in vivo suggest...

Differences on nitrogen availability in a soil amended with fresh, composted and thermally-dried sewage sludge.

Science.gov (United States)

Tarrasón, D; Ojeda, G; Ortiz, O; Alcañiz, J M

2008-01-01

Anaerobically-digested sludge called fresh sludge (F), composted sludge (C) and thermally-drying sludge (T), all from the same batch, were applied to the surface of a calcareous Udic Calciustept with loamy texture. Dosage equivalent was 10 t ha(-1) of dry matter. The concentration of mineral nitrogen (ammonium and nitrate) in the soil was measured in order to estimate the effects of the post-treatments to which the different kinds of sewage sludge are subjected in relation to the availability of N in the surface layer of the soil. The most significant differences in NH(4)-N and NO(3)-N concentrations due to the transformation of the organic matter were observed during the first three weeks following soil amendment. Thermally-dried and composted sludge initially displayed higher concentrations of ammonium and nitrate in soil. Five months after the amendment, soil applied with fresh sludge showed the highest concentrations of NH(4)-N and NO(3)-N (6.1 and 36.6 mg kg(-1), respectively). It is clear that the processes of composting and thermal-drying influence the bioavailability of nitrogen from the different types of sewage sludge.

Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women: A randomized controlled trial.

Science.gov (United States)

Fathi, Yasamin; Ghodrati, Naeimeh; Zibaeenezhad, Mohammad-Javad; Faghih, Shiva

Controversy exists as to whether the lipid-lowering properties of kefir drink (a fermented probiotic dairy product) in animal models could be replicated in humans. To assess and compare the potential lipid-lowering effects of kefir drink with low-fat milk in a dairy-rich diet in overweight or obese premenopausal women. In this 8-week, single-center, multiarm, parallel-group, outpatient, randomized controlled trial, 75 eligible Iranian women aged 25 to 45 years were randomly allocated to kefir, milk, or control groups. Women in the control group received a weight-maintenance diet containing 2 servings/d of low-fat dairy products, whereas subjects in the milk and kefir groups received a similar diet containing 2 additional servings/d (a total of 4 servings/d) of dairy products from low-fat milk or kefir drink, respectively. At baseline and study end point, serum levels/ratios of total cholesterol (TC), low- and high-density lipoprotein cholesterol (LDLC and HDLC), triglyceride, Non-HDLC, TC/HDLC, LDLC/HDLC, and triglyceride/LDLC were measured as outcome measures. After 8 weeks, subjects in the kefir group had significantly lower serum levels/ratios of lipoproteins than those in the control group (mean between-group differences were -10.4 mg/dL, -9.7 mg/dL, -11.5 mg/dL, -0.4, and -0.3 for TC, LDLC, non-HDLC, TC/HDLC, and LDLC/HDLC, respectively; all P < .05). Similar results were observed in the milk group. However, no such significant differences were found between the kefir and milk groups. Kefir drink causes a significant yet similar improvement in serum lipid profile, compared with low-fat milk, in a dairy-rich diet in overweight or obese premenopausal women. Copyright © 2016 National Lipid Association. Published by Elsevier Inc. All rights reserved.

Evaluation of the isoflavone and total phenolic contents of kefir-fermented soymilk storage and after the in vitro digestive system simulation.

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da Silva Fernandes, Meg; Sanches Lima, Fernando; Rodrigues, Daniele; Handa, Cintia; Guelfi, Marcela; Garcia, Sandra; Ida, Elza Iouko

2017-08-15

This study aimed to evaluate the isoflavone and total phenolic contents in kefir-fermented soymilk storage and after the in vitro digestive system simulation (DSS). Soymilk was fermented with kefir culture (0.02UC/L) at 25°C for 15h and stored at 4°C for 4days. After the fermentation and storage, the isoflavone and total phenolic contents were quantified by high performance liquid chromatography and spectrophotometry, respectively. The cell viability of lactic acid bacteria and yeast was evaluated. Fermentation promoted an increase of approximately 3log CFU/g cycles of the microorganisms and the storage process did not alter the aglycone isoflavones and total phenolic contents. The content of aglycone isoflavones increased 2-fold, and the total phenolic content increased 9-fold. Therefore, kefir-fermented soymilk is a good source of aglycone isoflavones and phenolics, since the content of these substances was increased significantly after the in vitro digestive system simulation of the product. Copyright © 2017 Elsevier Ltd. All rights reserved.

Aceitação e perfil sensorial das cachaças produzidas com Kefir e Saccharomyces cerevisae Acceptance and sensory profile of cachaça produced using Kefir and Saccharomyces cerevisae

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Anita Saraiva Dornelles

2009-09-01

Full Text Available A levedura Saccharomyces cerevisae é o microrganismo mais utilizado industrialmente nas destilarias, mas outros microrganismos também são capazes de produzir etanol utilizando matérias-primas açucaradas como substrato. O objetivo deste trabalho foi determinar o perfil sensorial e a aceitação da aguardente de cana produzida através da fermentação alcoólica com grânulos de Kefir, comparando-a ao produto obtido tradicionalmente. Pelo método de ADQ, 8 provadores treinados avaliaram os seguintes descritores: aroma alcoólico e de cachaça, sabor alcoólico e de cachaça, gosto amargo e ardência. O teste de aceitação foi realizado por 57 consumidores de aguardente, utilizando-se uma escala hedônica estruturada de nove pontos para avaliar a aceitação do aroma e a aceitação global. A cachaça com Kefir apresentou maior intensidade de aroma alcoólico e gosto amargo, obtendo menor aceitação global que a cachaça de levedura. Dessa forma, o produto foi considerado de grande potencial visto que apresentou satisfatório percentual de aprovação entre os consumidores.Saccharomyces cerevisae is the main industrially used yeast to produce sugar cane spirits (cachaça. However, other microorganisms are able to produce ethanol using sugar as substrate. This work aimed at determining the sensory profile of cachaça produced through the alcoholic fermentation with Kefir's granules and its acceptance. The acceptance analysis was performed by 57 consumers using a 9 point structured hedonic scale to evaluate the aroma and the general acceptance of the product. The QDA method, with 8 trained tasters, was used to evaluate the following product descriptors: alcoholic aroma, alcoholic flavor, and burning and bitter taste. The evaluated samples did not presented statistical differences (p < 0.05 among each other regarding the aroma acceptance. However, the cachaça produced using bakery yeast presented higher acceptance scores. On the other hand

Characterization of lactococci isolated from homemade kefir

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Kojić M.

2007-01-01

Full Text Available Five bacteriocin-producing lactococci isolates from traditionally prepared kefir were determined as Lactococcus lactis subsp. lactis. The analyzed isolates showed different plasmid profiles and no cross inhibition between them was detected. Moreover, natural isolate BGKF26 was resistant to the antimicrobial activity of nisin producing strain NP45. Plasmid curing experiments revealed that the genes encoding bacteriocin and proteinase production are located on separate genetic elements, except in BGKF26. Production of the tested bacteriocins depends on the concentration of casitone or triptone in the medium. Higher concentrations of casitone or triptone induce bacteriocin activity. Our DNA-DNA hybridization analyses suggest that the analyzed antimicrobial compounds probably are lactococcin-like bacteriocins.

Atividade antiinflamatória de carboidrato produzido por fermentação aquosa de grãos de quefir Anti-inflammatory activity of carbohydrate produced from aqueous fermentation of kefir

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Maria E. C. Moreira

2008-01-01

Full Text Available Kefir, a symbiont microorganism suspension, presents benefic effects to health. Some kefir grains were cultivated in brown sugar, allowing to isolate a substance named CSQ. This was evaluated on a biologic essay of mouse foot edema, presenting an inhibitory activity of 30+4 % against carrageenan after the stimulus. It was observed that a cultivation mean containing sucrose, and not the milky mean, lead to the production of different sugar polymeric chains of kefir. The results in vivo suggest that the CSQ exerted an anti-inflammatory activity.

The effects of dietary kefir and low molecular weight sodium alginate on serum immune parameters, resistance against Streptococcus agalactiae and growth performance in Nile tilapia (Oreochromis niloticus).

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Van Doan, Hien; Hoseinifar, Seyed Hossein; Tapingkae, Wanaporn; Khamtavee, Pimporn

2017-03-01

The present study evaluates the effects of dietary kefir and low molecular weight sodium alginate (LWMSA) (singular or combined) on non-specific immune response, disease resistance and growth performance of Nile tilapia (Oreochromis niloticus). Fish with average weight of 18.60 ± 0.04 g were supplied and randomly stocked in sixteen glass tanks (150 L) at density of 20 fish per tank. Fish were fed experimental diets as follows: 0 g kg -1 LMWSA (Control, Diet 1), 10 g kg -1 LMWSA (Diet 2), 40 g kg -1 kefir (Diet 3), and 10 g kg -1 LMWSA + 40 g kg -1 kefir (Diet 4) for 50 days. At the end of the feeding trial, serum lysozyme (SL), phagocytosis (PI), respiratory burst (RB), and alternative complement (ACH50) activities as well as growth performance were measured. Singular and combined administration of kefir and low molecular weight sodium alginate (LMWSA) significantly increased serum SL, PI, RB, and ACH50 activities compared control group (P < 0.05); the highest innate immune responses were observed in fish fed combinational diet (kefir + LMWSA) (P < 0.05). The results of experimental challenge revealed significantly higher resistance against Streptococcus agalactiae in fish fed supplemented diets and the highest post challenge survival rate was observed in synbiotic diet (P < 0.05). Similar results obtained in case of growth parameters. Feeding on supplemented diet significantly improved SGR and FCR and the highest growth parameters was observed in fish fed synbiotic diet (P < 0.05). These finding revealed that combined administration of dietary kefir and LMWSA can be considered for improving immune response, disease resistance and growth performance of Nile tilapia. Copyright © 2017 Elsevier Ltd. All rights reserved.

Characteristics of ammonia emission during thermal drying of lime sludge for co-combustion in cement kilns.

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Liu, Wei; Xu, Jingcheng; Liu, Jia; Cao, Haihua; Huang, Xiang-Feng; Li, Guangming

2015-01-01

Thermal drying was used to reduce sludge moisture content before co-combustion in cement kilns. The characteristics of ammonia (NH3) emission during thermal drying of lime sludge (LS) were investigated in a laboratory-scale tubular dry furnace under different temperature and time conditions. As the temperature increased, the NH3 concentration increased in the temperature range 100-130°C, decreased in the temperature range 130-220°C and increased rapidly at >220°C. Emission of NH3 also increased as the lime dosage increased and stabilized at lime dosages>5%. In the first 60 min of drying experiments, 55% of the NH3 was released. NH3 accounted for about 67-72% of the change in total nitrogen caused by the release of nitrogen-containing volatile compounds (VCs) from the sludge. X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy revealed that the main forms of nitrogen in sludge were amides and amines. The addition of lime (CaO) could cause conversion of N-H, N-O or C-N containing compounds to NH3 during the drying process.

Characterization of an exopolysaccharide produced by Lactobacillus plantarum YW11 isolated from Tibet Kefir.

Science.gov (United States)

Wang, Ji; Zhao, Xiao; Tian, Zheng; Yang, Yawei; Yang, Zhennai

2015-07-10

An exopolysaccharide (EPS)-producing strain YW11 isolated from Tibet Kefir was identified as Lactobacillus plantarum, and the strain was shown to produce 90 mgL(-1) of EPS when grown in a semi-defined medium. The molecular mass of the EPS was 1.1 × 10(5)Da. The EPS was composed of glucose and galactose in a molar ratio of 2.71:1, with possible presence of N-acetylated sugar residues in the polysaccharide as confirmed by NMR spectroscopy. Rheological studies showed that the EPS had higher viscosity in skim milk, at lower temperature, or at acidic pH. The viscous nature of the EPS was confirmed by observation with scanning electron microscopy that demonstrated a highly branched and porous structure of the polysaccharide. The atomic force microscopy of the EPS further revealed presence of many spherical lumps, facilitating binding with water in aqueous solution. The EPS had a higher degradation temperature (287.7°C), suggesting high thermal stability of the EPS. Copyright © 2015 Elsevier Ltd. All rights reserved.

Kefir ve Sağlık

OpenAIRE

DAYISOYLU, Kenan Sinan; KÖROĞLU, Özge; BAKIR, Esra; ULUDAĞ, Günsel; KÖROĞLU, Sedat

2015-01-01

Özet: Son yıllarda toplumlar beslenme konusunda giderek daha bilinçli hale gelmektedir. Beslenme konusunda temel talep olan sağlıklı ve güvenli gıdalar tüketebilme isteğinin yanında; insan sağlığına ek faydalar sağlayan, hastalıklardan koruma potansiyeli olan ve fonksiyonel gıda olarak adlandırılan ürünlere ulaşma isteği de giderek artmaktadır. Kefir, fonksiyonel gıdalardan probiyotikler alt kolunun önemli bir üyesi olup, içeriğinde birçok faydalı maya ve bakteri bulunduran, son yıllarda popü...

Immunohistochemical examination of effects of kefir, koumiss and commercial probiotic capsules on platelet derived growth factor-c and platelet derived growth factor receptor-alpha expression in mouse liver and kidney.

Science.gov (United States)

Bakir, B; Sari, E K; Aydin, B D; Yildiz, S E

2015-04-01

We investigated using immunohistochemistry the effects of kefir, koumiss and commercial probiotic capsules on the expression of platelet derived growth factor-c (PDGF-C) and platelet derived growth factor receptor-alpha (PDGFR-α) in mouse liver and kidney. Mice were assigned to four groups: group 1 was given commercial probiotic capsules, group 2 was given kefir, group 3 was given koumiss and group 4 was untreated. After oral administration for 15 days, body weights were recorded and liver and kidney tissue samples were obtained. Hematoxylin and eosin staining was used to examine histology. PDGF-C and PDGFR-α in liver and kidney were localized using the streptavidin-biotin peroxidase complex method (ABC). We found that the weights of the mice in the kefir, koumiss and commercial probiotic capsules groups increased compared to the control group. No differences in liver and kidney histology were observed in any of the experimental groups. Kefir, koumiss and the commercial probiotic preparation increased PDGF-C and PDGFR-α expression.

Goat Milk Kefir Supplemented with Porang Glucomannan Improves Lipid Profile and Haematological Parameter in Rat Fed High Fat and High Fructose Diet

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Nurliyani

2018-03-01

Full Text Available Background and Aims: Diet with a high fat and high sugar is associated with an increased incindence of the metabolic syndrome. Kefir has been known as a natural probiotic, while glucomannan from porang (Amorphophallus oncophyllus tuber was demonstrated as prebiotic in vivo. Probiotics and prebiotics can be used adjuvant nutritional therapy for metabolic syndrome. The aim of this study was to evaluate the effect of goat milk kefir supplemented with porang glucomannan on the lipid profile and haematological parameters in rats fed with a high-fat/high-fructose (HFHF diet.

Optimization of processing conditions to improve antioxidant activities of apple juice and whey based novel beverage fermented by kefir grains.

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Sabokbar, Nayereh; Khodaiyan, Faramarz; Moosavi-Nasab, Marzieh

2015-06-01

A central composite design (CCD) was used to evaluate the effects of fermentation temperature (20-30 ºC) and kefir grains amount (2-8%w/v) on total phenolic content and antioxidant activities of apple juice and whey based novel beverage fermented by kefir grains. The response surface methodology (RSM) showed that the significant second-order polynomial regression equation with high R(2) (>0.86) was successfully fitted for all response as function of independent variable. The overall optimum region was found to be at the combined level of 7.56%w/v kefir grains and temperature of 24.82 ºC with the highest value for total phenolic content (TPC) and antioxidant activities. At this optimum point TPC, 1, 1-Diphenyl-2-picrylhydrazyl radical scavenging, metal chelating effect, reducing power, inhibition of linoleic acid autoxidation and inhibition of ascorbate autoxidation were 165.02 mgGA/l, 0.38 ml/1 ml, 0.757 (absorbance at 700 nm), 46.12 %, 65.33 % and 21 %, respectively. No significant difference (p < 0.05) was found between actual values and predicated values.

Combined Thermal Management and Power Generation Concept for the Spent Fuel Dry Storage Cask

International Nuclear Information System (INIS)

Kim, In Guk; Bang, In Cheol

2017-01-01

The management of the spent nuclear fuel generated by nuclear power plants is a major issue in Korea due to insufficient capacity of the wet storage pools. Therefore, it is considered that dry storage system is the one possible solution for storing spent fuel. A dual-purpose metal cask (transportation and storage) is currently developing in Korea. This cask has 21 of fuel assemblies and 16.8 kW of maximum decay heat. To evaluate the critical safety in normal/off normal and accident conditions, critical stabilities were conducted by using CSAS 6.0. The experimental investigation of heat removal of a concrete storage cask was also conducted under normal, off normal and accident conditions. The results of the evaluation showed a good safety of the dry storage cask. The results showed the enhanced thermal performance according to modification of flow rate. To verify combined thermal management and power generation concept, a new type of test facility for dry storage cask was designed in 1/10 scale of concrete dry storage cask. The experimental study involved the cooling methods that are an integrated system on the top of the dry cask and air flow path on the canister wall. The results showed the temperature distribution of the wall and inside of the dry cask at the normal condition. The influence of the change of the heat load and cooling system were investigated. The heat removal by the integrated system is approximately 20% of the total heat removal of the dry cask with reduced wall temperature. In these tests, economic analysis is conducted by applying the concept of the cost and efficiency. Under different decay power cases, the energy efficiency of the heat pipe and Stirling engine are determined and compared based on experimental results. The average efficiencies of the Stirling engine were the range of 2.375 to 3.247% under the power range of 35– 65W. These results showed that advanced dry storage concept had a better cooling performance in comparison with

Thermal modeling of the forced convection Sandwich Greenhouse drying system for rubber sheets

International Nuclear Information System (INIS)

Tanwanichkul, B.; Thepa, S.; Rordprapat, W.

2013-01-01

Highlights: • Sandwich Greenhouse is designed for better quality and efficiency of rubber sheet drying. • Thermal models are developed to predict the convection heat transfer coefficient. • The models are validated and show good agreement with the actual experimental data. • The proposed greenhouse can maintain 40–60 °C, suitable for rubber sheet drying. • This greenhouse can bring down the moisture content to 2.8% in fewer than 2 days. - Abstract: In this paper, a novel “Sandwich Greenhouse” for rubber sheet drying is proposed. Using solar energy as the only heat source instead of traditional smoke house that requires firewood, it eliminates shortcomings such as skilled labor monitoring requirement, possible fire hazard, and darken-color rubber sheets due to soot particle contamination. Our greenhouse is specially designed to retain solar energy within, while minimizing the heat loss to the outside environment. The mathematical models are developed to predict the convection mass transfer coefficient and to study the thermal behavior during the drying of rubber sheets under our proposed greenhouse design. Validated with experimental observations, the models show good agreement with the actual experimental data. The experiment demonstrates an effectiveness of our proposed Sandwich Greenhouse, as the temperature of the rubber sheet is 15 °C and 5 °C higher than the ambient temperature during the daytime and nighttime, respectively. As a result, the moisture content of the rubber sheets can decrease from 36.4% to 2.8% in fewer than 2 days

IDENTIFICAÇÃO PRESUNTIVA DE LEVEDURAS DE INTERESSE BIOTECNOLÓGICO EM GRÃOS DE KEFIR

Directory of Open Access Journals (Sweden)

Fernanda Mincev ANTONIASSI

2017-12-01

Full Text Available Os grãos de Kefir são constituídos por uma matriz de polissacarídeos, ricos em micro-organismos simbióticos, gerando após a fermentação de açúcares, uma bebida probiótica que recebe o mesmo nome. A vasta população microbiana presente nestes grãos, incluindo leveduras e bactérias, oferece diversas características únicas à bebida. Estudos apontam que esta possui efeitos antitumorais, anti-inflamatórios, antimicrobiano, modulatório do sistema imune, anticolesterolêmico, dentre outros, devido as moléculas secretadas pelas células microbianas presente no microambiente dos grãos de Kefir. Diante disso, o objetivo deste estudo foi isolar e identificar, presuntivamente, leveduras presentes nos grãos de Kefir, possíveis produtoras de produtos de interesse biotecnológico. Para tanto, foram utilizados grãos da região de Bauru/SP, mantidos em fermentação em água/açúcar mascavo e em leite. Em seguida, os grãos foram triturados e semeados em ágar Sabouraud com cloranfenicol. Os isolados com características macroscópicas leveduriformes foram analisados por exame direto, prova do tubo germinativo e prova da ureia. Os dados obtidos foram comparados com atlas micológicos e chaves de identificação. No total foram isoladas seis colônias diferentes com presença de leveduras como Candida sp. e Saccharomyces sp., que possuem grande relevância para os processos biotecnológicos.

Desarrollo de un alimento funcional deshidratado constituido por microorganismos aislados de Kefir

OpenAIRE

Bolla, Patricia Araceli

2011-01-01

A pesar de los numerosos estudios sobre probióticos que encontramos en la actualidad, poco se conoce respecto a complejos multicepas. En este trabajo de tesis se propuso: 1- Desarrollar una mezcla microbiana constituida por microorganismos aislados de kefir. 2- Estudiar sus características tecnológicas y potencialmente probióticas. 3- Determinar la capacidad inhibitoria frente a Shigella y Clostridium difficile. 4- Estudiar la capacidad de la mezcla mic...

Spent fuel dry storage technology development: report of consolidated thermal data

International Nuclear Information System (INIS)

Lundberg, W.L.

1980-09-01

Experiments indicate that PWR fuel with decay heat levels in excess of 2 kW could be stored in isolated drywells in Nevada Test Site soil without exceeding the current fuel clad temperature limit (715 0 F). The document also assesses the ability to thermally analyze near-surface drywells and above-ground storage casks and it identifies analysis development areas. It is concluded that the required analysis procedures, computer programs, etc., are already developed and available. Analysis uncertainties, however, still exist but they lie mainly in the numerical input area. Soil thermal conductivity, of primary importance in analysis, requires additional study to better understand the soil drying mechanism and effects of moisture. Work is also required to develop an internal canister subchannel model. In addition, the ability of the overall drywell thermal model to accommodate thermal interaction effects between adjacent drywells should be confirmed. In the experimental area, tests with two BWR spent fuel assemblies encapsulated in a single canister should be performed to establish the fuel clad and canister temperature relationship. This is needed to supplement similar experimental work which has already been completed with PWR fuel

Draft Genome Sequences of Three Novel Low-Abundance Species Strains Isolated from Kefir Grain.

Science.gov (United States)

Kim, Yongkyu; Blasche, Sonja; Patil, Kiran R

2017-09-28

We report here the genome sequences of three novel bacterial species strains- Bacillus kefirresidentii Opo, Rothia kefirresidentii KRP, and Streptococcus kefirresidentii YK-isolated from kefir grains collected in Germany. The draft genomes of these isolates were remarkably dissimilar (average nucleotide identities, 77.80%, 89.01%, and 92.10%, respectively) to those of the previously sequenced strains. Copyright © 2017 Kim et al.

Kaybolmuş bir İçecek Kefir

OpenAIRE

Zekâi Varnacı

2015-01-01

Kafkasya’da bir parça dana veya koyun şirdeni keçi tulumlarında inek sütüyle maserasyona bırakılarak hazırlanır. Süt çabuk ve spontan olarak koagüle olur. Bundan sonra tulum yeniden doldurularak yeni bir işleme geçilir. Birkaç hafta sonra tulumun iç cidarlarında yavaş yavaş süngerimsi bir kabuk tabakası oluşur. İşte bu kabuk tabakası bölünüp veya kasılıp, sonra kurutularak kefir daneleri meydana getirilir. Danelerin görünüşü sarımsı, küçük, tomurcuğumsudur. Bu daneler kefirin hazırlanmasında ...

Kaybolmuş bir İçecek Kefir

OpenAIRE

Varnacı, Zekai

1980-01-01

Kafkasya’da bir parça dana veya koyun şirdeni keçi tulumlarında inek sütüyle maserasyona bırakılarak hazırlanır. Süt çabuk ve spontan olarak koagüle olur. Bundan sonra tulum yeniden doldurularak yeni bir işleme geçilir. Birkaç hafta sonra tulumun iç cidarlarında yavaş yavaş süngerimsi bir kabuk tabakası oluşur. İşte bu kabuk tabakası bölünüp veya kasılıp, sonra kurutularak kefir daneleri meydana getirilir. Danelerin görünüşü sarımsı, küçük, tomurcuğumsudur. Bu daneler kefirin hazırlanmasınd...

Long-term (12-month) improvement in meibomian gland function and reduced dry eye symptoms with a single thermal pulsation treatment.

Science.gov (United States)

Greiner, Jack V

2013-08-01

To determine the 1-year post-treatment dry eye status of subjects with meibomian gland dysfunction and dry eye symptoms after receiving a single LipiFlow Thermal Pulsation System treatment. Single-centre, prospective, observational, open-label, 1-month-registered clinical trial with a 1-year follow-up examination. Patients with evaporative dry eye disease with meibomian gland dysfunction and dry eye symptoms who had participated in the registered 1-month clinical trial. Eighteen of 30 subjects initially enrolled were able to return for a 1-year follow-up. Both eyes of all patients were treated with a single 12-min treatment using the LipiFlow Thermal Pulsation System. Meibomian gland function, tear break-up time and dry eye symptoms were measured. Data are presented for pretreatment (baseline), and 1-month and 1-year post-treatment. Meibomian gland secretion scores, and tear break-up time and dry eye symptoms. Significant improvement in meibomian gland secretion scores from baseline measurements (4.0 ± 3.4) to 1-month post-treatment (11.3 ± 4.7; P treatment (6.0 ± 4.4). The significant improvement in symptom scores on Ocular Surface Disease Index and Standard Patient Evaluation of Eye Dryness questionnaires observed at 1-month (P Eye Dryness [P treatment with the Lipi Flow Thermal Pulsation System offers an effective treatment for evaporative dry eye and meibomian gland dysfunction resulting in significant and sustained improvement in signs and symptoms for up to 1 year. © 2012 The Author. Clinical and Experimental Ophthalmology © 2012 Royal Australian and New Zealand College of Ophthalmologists.

Thermal drying of sewage plant sludge and its disposal; El secado termico de fangos de EDAR y su disposicion

Energy Technology Data Exchange (ETDEWEB)

Elias, X.

2002-07-01

Thermal drying is one more link in the sludge treatment chain. The thickeners transfer the wastes water contaminant to the primary sludge, which contains around 5% of dry matter (DM). Mechanical dehydration brings the proportion of DM up to between 20% and 40%. Thermal drying raises the proportion of DM to between 85% and 95%. These are the solutions that have been adopted in most of the European Union. The next step consists in eliminating the organic fraction, which makes up from 40% to 60% of the DM, from the sludge. This can be done by pyrolysis-gasification or incineration. Although incineration provides the energy needed to dry the sludge and also complies with the Directive that limits the disposal of fermentable matter on dumps, it inevitably leaves behind the inorganic waste presents in the sludge. Vitrification is a simple, complementary technology for making the inorganic fraction inert while allowing it to be valorized. It thus closes the cycle and achieves zero dumping. (Author) 28 refs.

Comparison of Thermal Stability of Dry High-strength Concrete and Wet High-strength Concrete

Science.gov (United States)

Musorina, Tatiana; Katcay, Aleksandr; Selezneva, Anna; Kamskov, Victor

2018-03-01

High-strength concrete is a modern material, which occupies it`s own niche on the construction material market. It is applicable in a large-scale high-rise construction, particularly an underground construction is a frequently used solution for a space saving. Usually underground structure is related to a wet usage environment. Though not all properties of the high-strength concrete are investigated to the full extent. Under adverse climatic conditions of the Russian Federation one of the most important properties for constructional materials is a thermal capacity. Therefore, the main purpose of the paper is to compare a thermal capacity of the high-strength concrete in humid conditions and a thermal capacity of the high-strength concrete in dry operational condition. During the study dependency between thermal capacity and design wall thickness and ambient humidity has to be proven with two experiments. As a result the theoretical relation between thermal capacity characteristic - thermal inertia and wall thickness and ambient humidity was confirmed by the experimental data. The thermal capacity of a building is in direct ratio to the construction thickness. It follows from the experiments and calculations that wet high-strength concrete has less thermal stability.

Kaybolmuş bir İçecek Kefir

Directory of Open Access Journals (Sweden)

Zekâi Varnacı

2015-02-01

Full Text Available Kafkasya’da bir parça dana veya koyun şirdeni keçi tulumlarında inek sütüyle maserasyona bırakılarak hazırlanır. Süt çabuk ve spontan olarak koagüle olur. Bundan sonra tulum yeniden doldurularak yeni bir işleme geçilir. Birkaç hafta sonra tulumun iç cidarlarında yavaş yavaş süngerimsi bir kabuk tabakası oluşur. İşte bu kabuk tabakası bölünüp veya kasılıp, sonra kurutularak kefir daneleri meydana getirilir. Danelerin görünüşü sarımsı, küçük, tomurcuğumsudur. Bu daneler kefirin hazırlanmasında maya olarak kullanılmak üzere ticarete arzedilir.

Drying of Rhinacanthus nasutus (Linn. Kurz. using a solar dryer incorporated with a backup thermal energy storage from wood combustion

Directory of Open Access Journals (Sweden)

Perapong Tekasakul

2006-05-01

Full Text Available An indirect, natural convection, solar cabinet dryer incorporated with a backup thermal energy storage from wood combustion was designed and tested with the Thai herb, Rhinacanthus nasutus (Linn. Kurz. Most of Thai herbs are widely used as traditional medicine and drying is an initial step in the production process. Solar dryer with a biomass backup heating system is the most feasible solution to drying in Thailand. In this work, a 4 m x 5 m solar collector was used to absorb solar radiation for heating the incoming air during the daytime, while a biomass burner was used to supply heat when solar energy was not possible. Heat from fuelwood combustion was accumulated in the thermal storage system made of bricks, and was used to heat up the incoming air. Results showed that the herb was dried uniformly and the temperature inside the drying cabinet could be maintained above 50ºC for more than 10 hours. Thermal efficiency when using solar energy was 10.5%, but the value was less than 1% when using the heat from biomass burning. This resulted from the low moisture content of the products after being dried by the solar energy. The dryer is beneficial to the operators, particularly in southern Thailand, where continuous drying is required. This dryer is by no means limited to drying of the herb. Currently, four dryers of the same model have been used by farmer groups in southern Thailand for drying bananas, several types of herbs, fish, and other products. In economic consideration, its payback period is 5.5 years when compared with the LPG-equipped dryer. When the total cost and production capacity are considered, its payback period is about 6 years.

A simplified computational scheme for thermal analysis of LWR spent fuel dry storage and transportation casks

International Nuclear Information System (INIS)

Kim, Chang Hyun

1997-02-01

A simplified computational scheme for thermal analysis of the LWR spent fuel dry storage and transportation casks has been developed using two-step thermal analysis method incorporating effective thermal conductivity model for the homogenized spent fuel assembly. Although a lot of computer codes and analytical models have been developed for application to the fields of thermal analysis of dry storage and/or transportation casks, some difficulties in its analysis arise from the complexity of the geometry including the rod bundles of spent fuel and the heat transfer phenomena in the cavity of cask. Particularly, if the disk-type structures such as fuel baskets and aluminium heat transfer fins are included, the thermal analysis problems in the cavity are very complex. To overcome these difficulties, cylindrical coordinate system is adopted to calculate the temperature profile of a cylindrical cask body using the multiple cylinder model as the step-1 analysis of the present study. In the step-2 analysis, Cartesian coordinate system is adopted to calculate the temperature distributions of the disk-type structures such as fuel basket and aluminium heat transfer fin using three- dimensional conduction analysis model. The effective thermal conductivity for homogenized spent fuel assembly based on Manteufel and Todreas model is incorporated in step-2 analysis to predict the maximum fuel temperature. The presented two-step computational scheme has been performed using an existing HEATING 7.2 code and the effective thermal conductivity for the homogenized spent fuel assembly has been calculated by additional numerical analyses. Sample analyses of five cases are performed for NAC-STC including normal transportation condition to examine the applicability of the presented simplified computational scheme for thermal analysis of the large LWR spent fuel dry storage and transportation casks and heat transfer characteristics in the cavity of the cask with the disk-type structures

A single LipiFlow® Thermal Pulsation System treatment improves meibomian gland function and reduces dry eye symptoms for 9 months.

Science.gov (United States)

Greiner, Jack V

2012-04-01

To evaluate the effect of a single treatment with the LipiFlow(®) Thermal Pulsation System on signs of meibomian gland dysfunction (MGD) and dry eye symptoms over a 9-month period. Patients (n = 42 eyes, 21 subjects) diagnosed with MGD and dry eye symptoms were recruited for a non-significant risk, prospective, open-label, 1-month clinical trial. Patients received a single 12-minute treatment using the LipiFlow(®) Thermal Pulsation System on each eye. The LipiFlow(®) device applies heat to the conjunctival surfaces of the upper and lower inner eyelids while simultaneously applying pulsatile pressure to the outer eyelid surfaces to express the meibomian glands. Patient symptoms were evaluated using the Ocular Surface Disease Index (OSDI) and Standard Patient Evaluation for Eye Dryness (SPEED) dry eye questionnaires; tear break-up time was measured with the dry eye test (DET™); and meibomian gland function was evaluated using a standardized diagnostic expression technique. Data are presented for patient's pre-treatment (baseline) and at 1-month and 9-month post-treatment. Meibomian gland secretion scores improved significantly from baseline (4.4 ± 4.0) to 1-month post-treatment (11.3 ± 6.2; p dry eye disease, the LipiFlow(®) Thermal Pulsation System offers a technological advancement for the treatment of dry eye disease secondary to meibomian gland dysfunction. A single 12-minute LipiFlow(®) treatment results in up to 9 months of sustained improvement of meibomian gland function, tear break-up time and dry eye symptoms that are unparalleled with current dry eye treatments.

Investigating the Plasma-Assisted and Thermal Catalytic Dry Methane Reforming for Syngas Production: Process Design, Simulation and Evaluation

Directory of Open Access Journals (Sweden)

Evangelos Delikonstantis

2017-09-01

Full Text Available The growing surplus of green electricity generated by renewable energy technologies has fueled research towards chemical industry electrification. By adapting power-to-chemical concepts, such as plasma-assisted processes, cheap resources could be converted into fuels and base chemicals. However, the feasibility of those electrified processes at large scale has not been investigated yet. Thus, the current work strives to compare, for first time in the literature, plasma-assisted production of syngas, from CH4 and CO2 (dry methane reforming, with thermal catalytic dry methane reforming. Specifically, both processes are conceptually designed to deliver syngas suitable for methanol synthesis (H2/CO ≥ 2 in mole. The processes are simulated in the Aspen Plus process simulator where different process steps are investigated. Heat integration and equipment cost estimation are performed for the most promising process flow diagrams. Collectively, plasma-assisted dry methane reforming integrated with combined steam/CO2 methane reforming is an effective way to deliver syngas for methanol production. It is more sustainable than combined thermal catalytic dry methane reforming with steam methane reforming, which has also been proposed for syngas production of H2/CO ≥ 2; in the former process, 40% more CO2 is captured, while 38% less H2O is consumed per mol of syngas. Furthermore, the plasma-assisted process is less complex than the thermal catalytic one; it requires higher amount of utilities, but comparable capital investment.

Technological functional properties of soy, oat and wheat fibers and soy products with added fibers and fermented with kefir culturePropriedades funcionais tecnológicas das fibras de soja, aveia e trigo e produtos de soja com adição de fibras e fermentados com cultura de kefir

Directory of Open Access Journals (Sweden)

Elza Iouko Ida

2012-02-01

Full Text Available The objective of this study was to characterize the technological functional properties of soy, oats and wheat fibers and evaluate soy products with added fiber and fermented with kefir. The fibers were characterized with regard to pH, water adsorption capacity, water and oil absorption capacity and swelling volume. Soy products were developed with the addition of 3% soy fiber, oat and wheat and fermented with kefir. The fermented products were characterized for pH, acidity, syneresis, viscosity and firmness, Lactococcus lactis counts and analysis of sanitary conditions. The soy fiber showed a higher content of protein and lipids, pH, water adsorption and adsorption capacity. The wheat fiber showed a higher oil absorption capacity. The addition of soy, oat and wheat fibers influence pH, acidity, syneresis, viscosity and firmness of fermented soy products with kefir. The lowest syneresis and highest viscosity and firmness were obtained with the soy fermented products with soy fiber. The addition of soy fiber stimulated Lactococcus lactis growth. The fermented soy products had enough Lactococcus lactis counts to be considered probiotics. The products presented satisfactory hygienic sanitary conditions.O objetivo deste trabalho foi caracterizar as propriedades funcionais tecnológicas das fibras de soja, aveia e trigo e avaliar os produtos de soja com adição de fibras e fermentados com cultura de kefir. As fibras foram caracterizadas quanto a composição química, pH, capacidade de adsorção e absorção de água, capacidade de absorção de óleo e volume de intumescimento. Foram desenvolvidos produtos de soja com adição de 3% de fibra de soja, aveia e trigo e fermentados com cultura de kefir. Os produtos fermentados foram caracterizados quanto o pH, acidez, sinerese, viscosidade e firmeza, contagem de Lactococcus lactis e análise das condições higiênico-sanitárias. A fibra de soja apresentou maior teor de proteínas e lipídios, p

Simulating thermal behavior of AECL's spent fuel dry storage system with CATHENA

International Nuclear Information System (INIS)

Sabourin, G.

1998-01-01

This paper documents the comparisons between CATHENA predictions and temperature measurements taken at the Gentilly-2 NPP spent fuel dry storage facility and in a mock--up of a storage basket placed inside a storage cylinder. It also presents CATHENA temperature predictions related to the storage of spent fuel in MACSTOR modules as planned for Ignalina NPP, Lithuania. CATHENA has been chosen because it can simulate many noncondensable gases including air and helium, and because of its great flexibility in the representation of the MACSTOR module geometry. The results of the simulations show good agreement with the experimental measurements. The two comparisons indicate that CATHENA can be used to simulate heat transfer from the fuel to the external air circuit of the spent fuel dry storage system. For the Ignalina MACSTOR module, containing RBMK fuel having higher heat release than typical CANDU fuel, CATHENA predicts that the maximum fuel temperature is expected to be around 240 deg C, giving an acceptable margin below the maximum allowed temperature of 300 deg C. In conclusion, this paper shows that the thermalhydraulic code CATHENA can accurately predict the thermal behavior AECL's air cooled spent fuel dry storage system. (author)

ANÁLISE SENSORIAL E MICROBIOLÓGICA DE KEFIR ARTESANAL PRODUZIDO A PARTIR DE LEITE DE CABRA E DE LEITE DE VACA

Directory of Open Access Journals (Sweden)

Felipe Alves de Almeida

2011-02-01

Full Text Available O kefir vem sendo considerado como um alimento funcional, produzido através da fermentação lática e alcoólica do leite por bactérias e leveduras, possuindo consistência semelhante à de um iogurte, mas de valor nutricional e terapêutico muito maior. É originário das montanhas dos Cáucaso e da Ásia Central tendo sido consumido por milhares de anos pela população das montanhas que relacionam seu uso diário com a longevidade e saúde. O objetivo deste trabalho foi elaborar um kefir a base de leite de vaca e outro a base de leite de cabra e avaliar suas características microbiológicas e a aceitabilidade de cada um dos produtos.

Dynamics of acoustic-convective drying of sunflower cake

Science.gov (United States)

Zhilin, A. A.

2017-10-01

The dynamics of drying sunflower cake by a new acoustic-convective method has been studied. Unlike the conventional (thermal-convective) method, the proposed method allows moisture to be extracted from porous materials without applying heat to the sample to be dried. Kinetic curves of drying by the thermal-convective and acoustic-convective methods were obtained and analyzed. The advantages of the acoustic-convective extraction of moisture over the thermal-convective method are discussed. The relaxation times of drying were determined for both drying methods. An intermittent drying mode which improves the efficiency of acoustic-convective extraction of moisture is considered.

Using Simplified Thermal Inertia to Determine the Theoretical Dry Line in Feature Space for Evapotranspiration Retrieval

Directory of Open Access Journals (Sweden)

Sujuan Mi

2015-08-01

Full Text Available With the development of quantitative remote sensing, regional evapotranspiration (ET modeling based on the feature space has made substantial progress. Among those feature space based evapotranspiration models, accurate determination of the dry/wet lines remains a challenging task. This paper reports the development of a new model, named DDTI (Determination of Dry line by Thermal Inertia, which determines the theoretical dry line based on the relationship between the thermal inertia and the soil moisture. The Simplified Thermal Inertia value estimated in the North China Plain is consistent with the value measured in the laboratory. Three evaluation methods, which are based on the comparison of the locations of the theoretical dry line determined by two models (DDTI model and the heat energy balance model, the comparison of ET results, and the comparison of the evaporative fraction between the estimates from the two models and the in situ measurements, were used to assess the performance of the new model DDTI. The location of the theoretical dry line determined by DDTI is more reasonable than that determined by the heat energy balance model. ET estimated from DDTI has an RMSE (Root Mean Square Error of 56.77 W/m2 and a bias of 27.17 W/m2; while the heat energy balance model estimated ET with an RMSE of 83.36 W/m2 and a bias of −38.42 W/m2. When comparing the coeffcient of determination for the two models with the observations from Yucheng, DDTI demonstrated ET with an R2 of 0.9065; while the heat energy balance model has an R2 of 0.7729. When compared with the in situ measurements of evaporative fraction (EF at Yucheng Experimental Station, the ET model based on DDTI reproduces the pixel scale EF with an RMSE of 0.149, much lower than that based on the heat energy balance model which has an RMSE of 0.220. Also, the EF bias between the DDTI model and the in situ measurements is 0.064, lower than the EF bias of the heat energy balance model

Novel technology development through thermal drying of encapsulated Kluyveromyces marxianus in micro- and nano-tubular cellulose in lactose fermentation and its evaluation for food production.

Science.gov (United States)

Papapostolou, Harris; Servetas, Yiannis; Bosnea, Loulouda A; Kanellaki, Maria; Koutinas, Athanasios A

2012-12-01

A novel technology development based on the production of a low-cost starter culture for ripening of cheeses and baking is reported in the present study. The starter culture comprises thermally dried cells of Kluyveromyces marxianus encapsulated in micro- and nano-tubular cellulose. For production of a low-cost and effective biocatalyst, whey was used as raw material for biomass production and thermal drying methods (convective, conventional, and vacuum) were applied and evaluated at drying temperatures ranging from 35 to 60 °C. The effect of drying temperature of biocatalysts on fermentability of lactose and whey was evaluated. Storage stability and suitability of biocatalysts as a commercial starter cultures was also assessed and evaluated. All thermally dried biocatalysts were found to be active in lactose and whey fermentation. In all cases, there was sugar conversion ranging from 92 to 100 %, ethanol concentration of up to 1.47 % (v/v), and lactic acid concentrations ranged from 4.1 to 5.5 g/l. However, convective drying of the encapsulated cells of K. marxianus in micro- and nano-tubular cellulose was faster and a more effective drying method while drying at 42 °C appear to be the best drying temperature in terms of cell activity, ethanol, and lactic acid formation. Storage of the biocatalysts for 3 months at 4 °C proved maintenance of its activity even though fermentation times increased by 50-100 % compared with the fresh dried ones.

Thermal-hydraulic experiment and analysis for interim dry storage of spent nuclear fuel

International Nuclear Information System (INIS)

Yoo, Seung Hun

2011-02-01

The experimental and numerical studies of interim storages for nuclear spent fuels have been performed to investigate thermal-hydraulic characteristics of the dry storage systems and to propose new methodologies for the analysis and the design. Three separate researches have been performed in the present study: (a) Development of a scaling methodology and thermal-hydraulic experiment of a single spent fuel assembly simulating a dry storage cask: (b) Full-scope simulation of a dry storage cask by the use of Computational Fluid Dynamics (CFD) code: (c) Thermal-hydraulic design of a tunnel-type interim storage facility. In the first study, a scaling methodology has been developed to design a scaled-down canister. The scaling was performed in two steps. For the first step, the height of a spent fuel assembly was reduced from full height to half height. In order to consider the effect of height reduction on the natural convection, the scaling law of Ishii and Kataoka (1984) was employed. For the second step, the quantity of spent fuel assemblies was reduced from multiple assemblies to a single assembly. The scaling methodology was validated through the comparison with the experiment of the TN24P cask. The Peak Cladding Temperature (PCT), temperature gradients, and the axial and radial temperature distribution in the nondimensional forms were in good agreement with the experimental data. Based on the developed methodology, we have performed a single assembly experiment which was designed to simulate the full scale of the TN24P cask. The experimental data was compared with the CFD calculations. It turns out that their PCTs were less than the maximum allowable temperature for the fuel cladding and that the differences of their PCTs were agreed within 3 .deg. C, which was less than measurement uncertainty. In the second study, the full-scope simulations of the TN24P cask were performed by FLUENT. In order to investigate the sensitivity of the numerical and physical

Nitrogen behaviour during thermal drying of mechanically dewatered biosludge from pulp and paper industry.

Science.gov (United States)

Mustonen, Kati; Deviatkin, Ivan; Havukainen, Jouni; Horttanainen, Mika

2018-04-01

An ongoing call to implement a circular economy is underway in the European Union, and a specific attention has been placed on the forest industry, which seeks additional recycling routes for its side streams, including biosludge. Biosludge is often dried and incinerated, thus wasting the nitrogen contained therein. This paper describes a study in which the release of nitrogen during thermal drying, the impact of the drying temperatures of 130°C, 180°C, and 210°C on the mass of ammonia released, and the potential for recovery of nitrogen from biosludge were examined. The results indicate that 1310-1730 mg kgTS -1 of nitrogen was released, which corresponded to 56-74% of the soluble nitrogen in biosolids or 4.0-5.3% of the total nitrogen. Of this released nitrogen, 83-85% was identified in condensate and absorbing water, thus indicating a high potential for recovering nitrogen from biosludge.

Scalable, "Dip-and-Dry" Fabrication of a Wide-Angle Plasmonic Selective Absorber for High-Efficiency Solar-Thermal Energy Conversion.

Science.gov (United States)

Mandal, Jyotirmoy; Wang, Derek; Overvig, Adam C; Shi, Norman N; Paley, Daniel; Zangiabadi, Amirali; Cheng, Qian; Barmak, Katayun; Yu, Nanfang; Yang, Yuan

2017-11-01

A galvanic-displacement-reaction-based, room-temperature "dip-and-dry" technique is demonstrated for fabricating selectively solar-absorbing plasmonic-nanoparticle-coated foils (PNFs). The technique, which allows for facile tuning of the PNFs' spectral reflectance to suit different radiative and thermal environments, yields PNFs which exhibit excellent, wide-angle solar absorptance (0.96 at 15°, to 0.97 at 35°, to 0.79 at 80°), and low hemispherical thermal emittance (0.10) without the aid of antireflection coatings. The thermal emittance is on par with those of notable selective solar absorbers (SSAs) in the literature, while the wide-angle solar absorptance surpasses those of previously reported SSAs with comparable optical selectivities. In addition, the PNFs show promising mechanical and thermal stabilities at temperatures of up to 200 °C. Along with the performance of the PNFs, the simplicity, inexpensiveness, and environmental friendliness of the "dip-and-dry" technique makes it an appealing alternative to current methods for fabricating selective solar absorbers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Perbandingan Susu Kambing dan Susu Kedelai dalam Pembuatan Kefir

Directory of Open Access Journals (Sweden)

E. Rossi

2016-02-01

Full Text Available Tujuan dari penelitian ini adalah untuk mendapatkan rasio terbaik susu kambing dengan susu kedelai untuk menghasilkan kualitas kefir tertinggi. Rancangan Acak Lengkap (RAL digunakan dalam penelitian ini dengan lima perlakuan dan empat ulangan. Perlakuannya adalah MS1 (susu kambing 100: susu kedelai 0, MS2 (susu kambing 75: susu kedelai 25, MS3 (susu kambing 50: susu kedelai 50, MS4 (susu kambing 25: susu kedelai 75, dan MS5 (susu kambing 0: susu kedelai 100. Parameter yang diamati adalah tingkat keasaman (pH, total bakteri asam laktat, padatan total dan kadar alkohol. Hasil penelitian menunjukkan bahwa rasio susu kambing dan susu kedelai berpengaruh nyata (P <0,05 terhadap pH, jumlah bakteri asam laktat, padatan total dan kadar alkohol. Perlakuan terbaik dalam penelitian ini adalah MS2.

Chemical, Physiochemical, and Microstructural Properties, and Probiotic Survivability of Fermented Goat Milk Using Polymerized Whey Protein and Starter Culture Kefir Mild 01.

Science.gov (United States)

Wang, Hao; Wang, Cuina; Wang, Mu; Guo, Mingruo

2017-11-01

A set-type fermented goat milk (FGM) using polymerized whey protein (PWP) as main thickening agent and Kefir Mild 01 as starter culture was developed. The FGM with PWP (0.3%, w/v) and pectin (0.2%, w/v) had low syneresis (5.44 ± 0.92%), desirable viscosity (952.86 ± 61.52 mPa⋅s), and hardness (112.57 ± 3.23 g), which were comparable to a fermented cow milk. Sensory evaluation data showed that the FGM with PWP and pectin had higher scores of both flavor (4.41 ± 0.39) and taste (3.72 ± 0.34) than the sample without PWP. Chemical composition of both fermented goat and cow milk were analyzed. The protein content of goat and cow milk samples were 3.50% ± 0.12% and 3.28% ± 0.09% (w/w), respectively. Lactobacillus acidophilus population in both FGM samples remained above 10 6 CFU/g during the 1st 4-wk storage. There was a slight but no significant (P > 0.05) decrease in pH and TA during storage. Scanning electron microscopy micrographs displayed a compact and homogeneous protein network of the FGM with PWP and pectin. Polymerized whey protein may be a novel protein-based thickening agent for formulation of a set-type FGM with starter culture Kefir Mild 01. Fermented goat milk is an increasingly popular dairy product in the world. However, it is difficult to make set type fermented goat milk due to the smaller size and lower content of casein micelles in goat milk. A fermented goat milk with PWP (0.3%, w/v) and pectin (0.2%, w/v) was successfully developed in this study. The product fermented by Kefir Mild 01 starter culture had a similar taste with Kefir but no yeast or alcoholic exists. The new product would be a promising food in the market. © 2017 Institute of Food Technologists®.

Bifidobacterium aquikefiri sp. nov., isolated from water kefir.

Science.gov (United States)

Laureys, David; Cnockaert, Margo; De Vuyst, Luc; Vandamme, Peter

2016-03-01

A novel Bifidobacterium , strain LMG 28769 T , was isolated from a household water kefir fermentation process. Cells were Gram-stain-positive, non-motile, non-spore-forming, catalase-negative, oxidase-negative and facultatively anaerobic short rods. Analysis of its 16S rRNA gene sequence revealed Bifidobacterium crudilactis and Bifidobacterium psychraerophilum (97.4 and 97.1 % similarity towards the respective type strain sequences) as nearest phylogenetic neighbours. Its assignment to the genus Bifidobacterium was confirmed by the presence of fructose 6-phosphate phosphoketolase activity. Analysis of the hsp60 gene sequence revealed very low similarity with nucleotide sequences in the NCBI nucleotide database. The genotypic and phenotypic analyses allowed the differentiation of strain LMG 28769 T from all recognized Bifidobacterium species. Strain LMG 28769 T ( = CCUG 67145 T  = R 54638 T ) therefore represents a novel species, for which the name Bifidobacterium aquikefiri sp. nov. is proposed.

Saccharomyces cerevisiae from Brazilian kefir-fermented milk: An in vitro evaluation of probiotic properties.

Science.gov (United States)

Lima, Meire Dos Santos Falcão de; Souza, Karoline Mirella Soares de; Albuquerque, Wendell Wagner Campos; Teixeira, José António Couto; Cavalcanti, Maria Taciana Holanda; Porto, Ana Lúcia Figueiredo

2017-09-01

The therapeutic use of probiotics for supporting the antibiotic action against gastrointestinal disorders is a current trend and emerging applications have gained popularity because of their support for various microbiological activities in digestive processes. Microorganisms isolated from kefir with great probiotic properties, in addition to high resistance to harsh environmental conditions, have been widely researched. Administration of probiotic yeasts offers a number of advantages, when compared to bacteria, because of particular characteristics as their larger cell size. In the present study, 28 strains of Saccharomyces cerevisiae were isolated, after in vitro digestion of kefir-fermented milk, and identified by molecular based approaches. A screening was performed to determine important quality requirements for probiotics including: antagonistic and antioxidant activities, β-galactosidase synthesis, autoaggregation, surface hydrophobicity and adhesion to epithelial cells. The results showed strains: with antagonistic activity against microbial pathogens such as Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis; able to produce β-galactosidase; with antioxidant activity levels higher than 90%; with hydrophobicity activity and autoaggregation ability (evaluated by adhesion test, where all the strains presented adhesion to mice ileal epithelial cells). These findings are relevant and the strains are recommended for further in vivo studies as well as for potential therapeutic applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

SLUDGE TREATMENT PROJECT KOP DISPOSITION - THERMAL AND GAS ANALYSIS FOR THE COLD VACUUM DRYING FACILITY

International Nuclear Information System (INIS)

Swenson, J.A.; Crowe, R.D.; Apthorpe, R.; Plys, M.G.

2010-01-01

The purpose of this document is to present conceptual design phase thermal process calculations that support the process design and process safety basis for the cold vacuum drying of K Basin KOP material. This document is intended to demonstrate that the conceptual approach: (1) Represents a workable process design that is suitable for development in preliminary design; and (2) Will support formal safety documentation to be prepared during the definitive design phase to establish an acceptable safety basis. The Sludge Treatment Project (STP) is responsible for the disposition of Knock Out Pot (KOP) sludge within the 105-K West (KW) Basin. KOP sludge consists of size segregated material (primarily canister particulate) from the fuel and scrap cleaning process used in the Spent Nuclear Fuel process at K Basin. The KOP sludge will be pre-treated to remove fines and some of the constituents containing chemically bound water, after which it is referred to as KOP material. The KOP material will then be loaded into a Multi-Canister Overpack (MCO), dried at the Cold Vacuum Drying Facility (CVDF) and stored in the Canister Storage Building (CSB). This process is patterned after the successful drying of 2100 metric tons of spent fuel, and uses the same facilities and much of the same equipment that was used for drying fuel and scrap. Table ES-l present similarities and differences between KOP material and fuel and between MCOs loaded with these materials. The potential content of bound water bearing constituents limits the mass ofKOP material in an MCO load to a fraction of that in an MCO containing fuel and scrap; however, the small particle size of the KOP material causes the surface area to be significantly higher. This relatively large reactive surface area represents an input to the KOP thermal calculations that is significantly different from the calculations for fuel MCOs. The conceptual design provides for a copper insert block that limits the volume available to

SLUDGE TREATMENT PROJECT KOP DISPOSITION - THERMAL AND GAS ANALYSIS FOR THE COLD VACUUM DRYING FACILITY

Energy Technology Data Exchange (ETDEWEB)

SWENSON JA; CROWE RD; APTHORPE R; PLYS MG

2010-03-09

The purpose of this document is to present conceptual design phase thermal process calculations that support the process design and process safety basis for the cold vacuum drying of K Basin KOP material. This document is intended to demonstrate that the conceptual approach: (1) Represents a workable process design that is suitable for development in preliminary design; and (2) Will support formal safety documentation to be prepared during the definitive design phase to establish an acceptable safety basis. The Sludge Treatment Project (STP) is responsible for the disposition of Knock Out Pot (KOP) sludge within the 105-K West (KW) Basin. KOP sludge consists of size segregated material (primarily canister particulate) from the fuel and scrap cleaning process used in the Spent Nuclear Fuel process at K Basin. The KOP sludge will be pre-treated to remove fines and some of the constituents containing chemically bound water, after which it is referred to as KOP material. The KOP material will then be loaded into a Multi-Canister Overpack (MCO), dried at the Cold Vacuum Drying Facility (CVDF) and stored in the Canister Storage Building (CSB). This process is patterned after the successful drying of 2100 metric tons of spent fuel, and uses the same facilities and much of the same equipment that was used for drying fuel and scrap. Table ES-l present similarities and differences between KOP material and fuel and between MCOs loaded with these materials. The potential content of bound water bearing constituents limits the mass ofKOP material in an MCO load to a fraction of that in an MCO containing fuel and scrap; however, the small particle size of the KOP material causes the surface area to be significantly higher. This relatively large reactive surface area represents an input to the KOP thermal calculations that is significantly different from the calculations for fuel MCOs. The conceptual design provides for a copper insert block that limits the volume available to

Treatment for meibomian gland dysfunction and dry eye symptoms with a single-dose vectored thermal pulsation: a review.

Science.gov (United States)

Blackie, Caroline A; Carlson, Alan N; Korb, Donald R

2015-07-01

Meibomian gland dysfunction (MGD) is understood to be a highly prevalent, chronic progressive disease and the leading cause of dry eye. All available published peer-reviewed results of the novel vectored thermal pulsation therapy for patients with MGD are investigated. The PubMed and meeting abstract search revealed a total of 31 peer-reviewed reports on vectored thermal pulsation therapy at the time of the search (eight manuscripts and 23 meeting abstracts). All manuscripts evidence a significant increase in meibomian gland function (∼3×) and symptom improvement post a single 12-min treatment. Additional reported objective measures such as osmolarity, tear break-up time, or lipid layer thickness also increased as a result of the therapy; however, not all findings were statistically significant. The randomized controlled studies evidence sustained gland function and symptom relief lasting out to 12 months. The uncontrolled case series evidence significantly longer duration of effect. A single 12 minute vectored thermal pulsation treatment allows for reducing dry eye symptoms, improving meibomian gland function and other correlates of the ocular surface health.

Farklı Isıl İşlem Görmüş İnek Sütlerinden Kefir Kültürü ve Tanesi ile Üretilen Kefirlerin Nitelikleri ve Dayanıklılığı Üzerine Araştırmalar

Directory of Open Access Journals (Sweden)

Ergin Oktar

2015-02-01

Full Text Available Kaynatılmış, pastörize ve sterilize inek sütlerine ayrı ayrı kefir tanesi ve kefir kültürü aşılanarak üretilen kefirlerin depolamanın 1., 6 ve 9. günlerinde fiziksel, kimyasal ve duyusal analizleri yapılmıştır. Kefir örneklerinin depolama süresince pH’ları düşmüş, asitlikleri yükselmiştir. Kefir üretiminde yağ, protein ve laktoz miktarlarında azalma görülmüştür. Depolamada yağ miktarı değişmezken protein ve laktoz miktarında az da olsa azalma görülmüştür. Serbest yağ asitleri gerek üretim gerekse depolama boyunca artış göstermiştir. Tane ile üretilen kefirlerde maya miktarı kültür ile üretilenlere göre daha fazladır. Alkol, asetaldehit ve aseton kefir üretimi sırasında oluşmuş, depolama sırasında artış göstermiştir. Tüm kefir örnekleri depolama süresince duyusal değerlendirmede beğeni kazanmıştır. Kefir kalitesinin; tane ve kültürü aşılama oranına, inkübasyon sıcaklığı ve süresine, katılan sütün bileşim ve uygulanan ısıl işleme bağlı olduğu belirlenmiştir.

Effects of Clear Kefir on Biomolecular Aspects of Glycemic Status of Type 2 Diabetes Mellitus (T2DM Patients in Bandung, West Java [Study on Human Blood Glucose, c Peptide and Insulin

Directory of Open Access Journals (Sweden)

Judiono J

2014-08-01

Full Text Available Background: Diabetes Mellitus (DM triggers an excessive reaction of free-radicals. It increases reactive oxygen species and reduces antioxidants status as well as the β cell damage. Clear kefir was used for DM therapies, however it limited biomolecular exploration of its bioactive roles. Research aimed to investigate the effects of clear kefir on the biomolecular nature of the glycemic status of T2DM in Bandung. Methods: The randomized pretest-posttest control group was conducted by 106 T2DM patients. Research was done in several hospitals in Bandung and Cimahi, West Java from 2012–2013. Samples were divided randomly into three groups: (1 T2DM with HbA1c 7 fed standard diet and supplemented 200 ml/day by clear kefir, (3 T2DM with HbA1c was fed a standard diet as a control group. Dose response was obtained from a preeliminary vivo study, and then converted to human dosage by year 2011. Intervention was effectively done for 30 days. HbA1c was measured by HPLC. Fasting blood glucose (FBG and Postprandial blood glucose levels (PBG were measured by enzymes levels. C Peptide and insulin were measured by Elisa. Data was analyzed by a statictics programme by significance p<0,05. Study was approved by ethic committee. Results : HbA1c was significantly reduced in delta level (p<0.01 and FBG (p<0.015 among kefir groups. PBG was not significantly reduced among groups. C-Peptide was significantly increased in delta level, except in control group (p<0.014. Insulin was reduced significantly, except in control group (p<0.003. Conclusions : Supplementation of clear kefir reduced blood glucose levels (HbA1c, FBG, PBG and increased c-peptide. Clear kefir’s biomolecular mechanisms and chemistry characterization is a challenge for future studies.

Nuclear thermal source transfer unit, post-blast soil sample drying system

Energy Technology Data Exchange (ETDEWEB)

Wiser, Ralph S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Valencia, Matthew J [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

2017-01-03

Los Alamos National Laboratory states that its mission is “To solve national security challenges through scientific excellence.” The Science Undergraduate Laboratory Internship (SULI) programs exists to engage undergraduate students in STEM work by providing opportunity to work at DOE facilities. As an undergraduate mechanical engineering intern under the SULI program at Los Alamos during the fall semester of 2016, I had the opportunity to contribute to the mission of the Laboratory while developing skills in a STEM discipline. I worked with Technology Applications, an engineering group that supports non-proliferation, counter terrorism, and emergency response missions. This group specializes in tool design, weapons engineering, rapid prototyping, and mission training. I assisted with two major projects during my appointment Los Alamos. The first was a thermal source transportation unit, intended to safely contain a nuclear thermal source during transit. The second was a soil drying unit for use in nuclear postblast field sample collection. These projects have given me invaluable experience working alongside a team of professional engineers. Skills developed include modeling, simulation, group design, product and system design, and product testing.

Nuclear thermal source transfer unit, post-blast soil sample drying system

International Nuclear Information System (INIS)

Wiser, Ralph S.; Valencia, Matthew J

2017-01-01

Los Alamos National Laboratory states that its mission is ''To solve national security challenges through scientific excellence.'' The Science Undergraduate Laboratory Internship (SULI) programs exists to engage undergraduate students in STEM work by providing opportunity to work at DOE facilities. As an undergraduate mechanical engineering intern under the SULI program at Los Alamos during the fall semester of 2016, I had the opportunity to contribute to the mission of the Laboratory while developing skills in a STEM discipline. I worked with Technology Applications, an engineering group that supports non-proliferation, counter terrorism, and emergency response missions. This group specializes in tool design, weapons engineering, rapid prototyping, and mission training. I assisted with two major projects during my appointment Los Alamos. The first was a thermal source transportation unit, intended to safely contain a nuclear thermal source during transit. The second was a soil drying unit for use in nuclear postblast field sample collection. These projects have given me invaluable experience working alongside a team of professional engineers. Skills developed include modeling, simulation, group design, product and system design, and product testing.

Effect of pre-irradiation on thermal inactivation of B. pumilus E 601 dry spores irradiated with EB and. gamma. -rays

Energy Technology Data Exchange (ETDEWEB)

Watanabe, Yuhei; Ito, Hitoshi; Ishigaki, Isao [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

1989-11-01

The survival fraction of B. pumilus spores irradiated with {gamma} -rays and electron beams in vacuum were increased when the spores were heated or allowed to stand in vacuum for a long time at room temperature. The survival curves of the spores thus treated after irradiation might give apparent radiation sensitivities which were lower than true ones obtained just after irradiation. On the contrary, the radiation sensitivities of the spores irradiated in dry air and then heated or allowed to stand in dry air became high. To elucidate the characteristics of th spores, the effect of heating on the radiation sensitivity of the B. pumilus spores has been studied. By heating the pre-irradiated spores in vacuum, its survival fraction was increased, in other words, the spores inactivated with radiation were recovered. However, the thermal sensitivity of the recovered spores was found to be high compared with that of the original spores. On the other hand, when B. pumilus spores were irradiated in dry air and then heated in dry air, the survival curves of the spores were found to be composed of two exponential curves, suggesting that two kinds of thermal inactivation mechanism existed. From Arrhenius plots of unirradiated B. pumilus spores, the activation energies of the thermal inactivation in the range of 90degC to 120degC in vacuum and in air were found to be about 38 kcal/mol and 29 kcal/mol, respectively. The activation energy of the spores at a temperature of higher than 120degC, however increased to give the same value (about 38 kcal/mol) as found in vacuum. This fact suggests the main mechanism of the thermal inactivation of the spores varies near 120degC. Arrhenius plots of irradiated spores in vacuum was similar to that of unirradiated ones. Thermal inactivation rates of the irradiated spores in the presence of air will also be discussed as compared with those of unirradiated ones. (author).

Thermal analysis of dry concrete canister storage system for CANDU spent fuel

International Nuclear Information System (INIS)

Ryu, Yong Ho

1992-02-01

This paper presents the results of a thermal analysis of the concrete canisters for interim dry storage of spent, irradiated Canadian Deuterium Uranium(CANDU) fuel. The canisters are designed to contain 6-year-old fuel safely for periods of 50 years in stainless steel baskets sealed inside a steel-lined concrete shield. In order to assure fuel integrity during the storage, fuel rod temperature shall not exceed the temperature limit. The contents of thermal analysis include the following : 1) Steady state temperature distributions under the conservative ambient temperature and insolation load. 2) Transient temperature distributions under the changes in ambient temperature and insolation load. Accounting for the coupled heat transfer modes of conduction, convection, and radiation, the computer code HEATING5 was used to predict the thermal response of the canister storage system. As HEATING5 does not have the modeling capability to compute radiation heat transfer on a rod-to-rod basis, a separate calculating routine was developed and applied to predict temperature distribution in a fuel bundle. Thermal behavior of the canister is characterized by the large thermal mass of the concrete and radiative heat transfer within the basket. The calculated results for the worst case (steady state with maximum ambient temperature and design insolation load) indicated that the maximum temperature of the 6 year cooled fuel reached to 182.4 .deg. C, slightly above the temperature limit of 180 .deg. C. However,the thermal inertia of the thick concrete wall moderates the internal changes and prevents a rise in fuel temperature in response to ambient changes. The maximum extent of the transient zone was less than 75% of the concrete wall thickness for cyclic insolation changes. When transient nature of ambient temperature and insolation load are considered, the fuel temperature will be a function of the long term ambient temperature as opposed to daily extremes. The worst design

Ambient Dried Aerogels

Science.gov (United States)

Jones, Steven M.; Paik, Jong-Ah

2013-01-01

A method has been developed for creating aerogel using normal pressure and ambient temperatures. All spacecraft, satellites, and landers require the use of thermal insulation due to the extreme environments encountered in space and on extraterrestrial bodies. Ambient dried aerogels introduce the possibility of using aerogel as thermal insulation in a wide variety of instances where supercritically dried aerogels cannot be used. More specifically, thermoelectric devices can use ambient dried aerogel, where the advantages are in situ production using the cast-in ability of an aerogel. Previously, aerogels required supercritical conditions (high temperature and high pressure) to be dried. Ambient dried aerogels can be dried at room temperature and pressure. This allows many materials, such as plastics and certain metal alloys that cannot survive supercritical conditions, to be directly immersed in liquid aerogel precursor and then encapsulated in the final, dried aerogel. Additionally, the metalized Mylar films that could not survive the previous methods of making aerogels can survive the ambient drying technique, thus making multilayer insulation (MLI) materials possible. This results in lighter insulation material as well. Because this innovation does not require high-temperature or high-pressure drying, ambient dried aerogels are much less expensive to produce. The equipment needed to conduct supercritical drying costs many tens of thousands of dollars, and has associated running expenses for power, pressurized gasses, and maintenance. The ambient drying process also expands the size of the pieces of aerogel that can be made because a high-temperature, high-pressure system typically has internal dimensions of up to 30 cm in diameter and 60 cm in height. In the case of this innovation, the only limitation on the size of the aerogels produced would be in the ability of the solvent in the wet gel to escape from the gel network.

Effect of milk fermentation by kefir grains and selected single strains of lactic acid bacteria on the survival of Mycobacterium bovis BCG.

Science.gov (United States)

Macuamule, C L S; Wiid, I J; van Helden, P D; Tanner, M; Witthuhn, R C

2016-01-18

Mycobacterium bovis that causes Bovine tuberculosis (BTB) can be transmitted to humans thought consumption of raw and raw fermented milk products from diseased animals. Lactic acid bacteria (LAB) used in popular traditional milk products in Africa produce anti-microbial compounds that inhibit some pathogenic and spoilage bacteria. M. bovis BCG is an attenuated non-pathogenic vaccine strain of M. bovis and the aim of the study was to determine the effect of the fermentation process on the survival of M. bovis BCG in milk. M. bovis BCG at concentrations of 6 log CFU/ml was added to products of kefir fermentation. The survival of M. bovis BCG was monitored at 12-h intervals for 72 h by enumerating viable cells on Middlebrook 7H10 agar plates enriched with 2% BD BACTEC PANTA™. M. bovis BCG was increasingly reduced in sterile kefir that was fermented for a period of 24h and longer. In the milk fermented with kefir grains, Lactobacillus paracasei subsp. paracasei or Lactobacillus casei, the viability of M. bovis BCG was reduced by 0.4 logs after 24h and by 2 logs after 48 h of fermentation. No viable M. bovis BCG was detected after 60 h of fermentation. Results from this study show that long term fermentation under certain conditions may have the potential to inactivate M. bovis BCG present in the milk. However, to ensure safety of fermented milk in Africa, fermentation should be combined with other hurdle technologies such as boiling and milk pasteurisation. Copyright © 2015 Elsevier B.V. All rights reserved.

Cultivating conditions effects on kefiran production by the mixed culture of lactic acid bacteria imbedded within kefir grains.

Science.gov (United States)

Zajšek, Katja; Goršek, Andreja; Kolar, Mitja

2013-08-15

The influence of fermentation temperature, agitation rate, and additions of carbon sources, nitrogen sources, vitamins and minerals on production of kefiran by kefir grains lactic acid bacteria was studied in a series of experiments. The main aim of the work was to increase the exopolysaccharide (EPS) production where customised milk was used as fermentation medium. It was proved that the controlling of culturing conditions and the modifying of fermentation medium conditions (i.e., carbon, nitrogen, mineral sources and vitamins) can dramatically enhance the production of the EPS. The temperature and agitation rate were critical for kefiran production during the 24 h cultivation of grains; our optimised conditions being 25°C and 80 rpm, respectively. In addition, when optimising the effects of additional nutrition, it was found that 5% (w/v) lactose, 0.1% (w/v) thiamine, and 0.1% (w/v) FeCl3 led to the maximal production of EPS. The results indicate that nutrients can be utilised to improve the production of EPS and that good kefir grains growth does not appear to be a determining factor for a high production yield of EPS. Copyright © 2013 Elsevier Ltd. All rights reserved.

Stabilization of Live Attenuated Influenza Vaccines by Freeze Drying, Spray Drying, and Foam Drying.

Science.gov (United States)

Lovalenti, Phillip M; Anderl, Jeff; Yee, Luisa; Nguyen, Van; Ghavami, Behnaz; Ohtake, Satoshi; Saxena, Atul; Voss, Thomas; Truong-Le, Vu

2016-05-01

The goal of this research is to develop stable formulations for live attenuated influenza vaccines (LAIV) by employing the drying methods freeze drying, spray drying, and foam drying. Formulated live attenuated Type-A H1N1 and B-strain influenza vaccines with a variety of excipient combinations were dried using one of the three drying methods. Process and storage stability at 4, 25 and 37°C of the LAIV in these formulations was monitored using a TCID50 potency assay. Their immunogenicity was also evaluated in a ferret model. The thermal stability of H1N1 vaccine was significantly enhanced through application of unique formulation combinations and drying processes. Foam dried formulations were as much as an order of magnitude more stable than either spray dried or freeze dried formulations, while exhibiting low process loss and full retention of immunogenicity. Based on long-term stability data, foam dried formulations exhibited a shelf life at 4, 25 and 37°C of >2, 1.5 years and 4.5 months, respectively. Foam dried LAIV Type-B manufactured using the same formulation and process parameters as H1N1 were imparted with a similar level of stability. Foam drying processing methods with appropriate selection of formulation components can produce an order of magnitude improvement in LAIV stability over other drying methods.

Simulating thermal behavior of AECL's spent fuel dry storage system with CATHENA

Energy Technology Data Exchange (ETDEWEB)

Sabourin, G. [Atomic Energy of Canada Limited, Montreal, PQ (Canada)

1998-07-01

This paper documents the comparisons between CATHENA predictions and temperature measurements taken at the Gentilly-2 NPP spent fuel dry storage facility and in a mock--up of a storage basket placed inside a storage cylinder. It also presents CATHENA temperature predictions related to the storage of spent fuel in MACSTOR modules as planned for Ignalina NPP, Lithuania. CATHENA has been chosen because it can simulate many noncondensable gases including air and helium, and because of its great flexibility in the representation of the MACSTOR module geometry. The results of the simulations show good agreement with the experimental measurements. The two comparisons indicate that CATHENA can be used to simulate heat transfer from the fuel to the external air circuit of the spent fuel dry storage system. For the Ignalina MACSTOR module, containing RBMK fuel having higher heat release than typical CANDU fuel, CATHENA predicts that the maximum fuel temperature is expected to be around 240 deg C, giving an acceptable margin below the maximum allowed temperature of 300 deg C. In conclusion, this paper shows that the thermalhydraulic code CATHENA can accurately predict the thermal behavior AECL's air cooled spent fuel dry storage system. (author)

Oxygen isotopic exchange occurring during dry thermal oxidation of 6H SiC

Energy Technology Data Exchange (ETDEWEB)

Vickridge, I.C. E-mail: vickridge@gps.jussieu.fr; Tromson, D.; Trimaille, I.; Ganem, J.-J.; Szilagyi, E.; Battistig, G

2002-05-01

SiC is a large band gap semiconductor, promising for high power and high frequency devices. The thermal oxide is SiO{sub 2} however the growth rates of thermal oxide on SiC are substantially slower than on Si, and different along the polar directions (<0 0 0 1-bar> and <0 0 0 1> in the hexagonal polytypes). Thorough understanding of the oxide growth mechanisms may give us new insights into the nature of the SiO{sub 2}/SiC interface, crucial for device applications. We have determined growth kinetics for ultra-dry thermal oxidation of 6H SiC at 1100 deg. C for pressures from 3 to 200 mbar. At 3 mbar, the lowest pressure studied, the oxide growth rates along the two polar directions are virtually the same. At higher pressures growth is faster on the carbon-terminated (0 0 0 1-bar) face. After consecutive oxidations at 1100 deg. C and 100 mbar in {sup 18}O{sub 2} and {sup 16}O{sub 2} gases, {sup 18}O depth profiles show significant isotopic exchange and oxygen movement within the oxide during oxidation.

A Parameterization of Dry Thermals and Shallow Cumuli for Mesoscale Numerical Weather Prediction

Science.gov (United States)

Pergaud, Julien; Masson, Valéry; Malardel, Sylvie; Couvreux, Fleur

2009-07-01

For numerical weather prediction models and models resolving deep convection, shallow convective ascents are subgrid processes that are not parameterized by classical local turbulent schemes. The mass flux formulation of convective mixing is now largely accepted as an efficient approach for parameterizing the contribution of larger plumes in convective dry and cloudy boundary layers. We propose a new formulation of the EDMF scheme (for Eddy DiffusivityMass Flux) based on a single updraft that improves the representation of dry thermals and shallow convective clouds and conserves a correct representation of stratocumulus in mesoscale models. The definition of entrainment and detrainment in the dry part of the updraft is original, and is specified as proportional to the ratio of buoyancy to vertical velocity. In the cloudy part of the updraft, the classical buoyancy sorting approach is chosen. The main closure of the scheme is based on the mass flux near the surface, which is proportional to the sub-cloud layer convective velocity scale w *. The link with the prognostic grid-scale cloud content and cloud cover and the projection on the non- conservative variables is processed by the cloud scheme. The validation of this new formulation using large-eddy simulations focused on showing the robustness of the scheme to represent three different boundary layer regimes. For dry convective cases, this parameterization enables a correct representation of the countergradient zone where the mass flux part represents the top entrainment (IHOP case). It can also handle the diurnal cycle of boundary-layer cumulus clouds (EUROCSARM) and conserve a realistic evolution of stratocumulus (EUROCSFIRE).

Thermal drying of the solid fraction from biogas digestate

DEFF Research Database (Denmark)

Pantelopoulos, Athanasios; Magid, Jakob; Jensen, Lars Stoumann

2016-01-01

Drying of solids produced from digestate is prone to N losses through NH3 volatilisation. The applicability of acidification as an NH3 emission mitigation technique during the drying of solids from digestate was assessed in a drying experiment. Operating conditions comprised four drying temperatu...

Antiobesity Effect of Exopolysaccharides Isolated from Kefir Grains.

Science.gov (United States)

Lim, Juha; Kale, Madhuvanti; Kim, Dong-Hyeon; Kim, Hong-Seok; Chon, Jung-Whan; Seo, Kun-Ho; Lee, Hyeon Gyu; Yokoyama, Wallace; Kim, Hyunsook

2017-11-22

Physiological properties of water-soluble exopolysaccharides (EPS) and residues after EPS removal (Res) from the probiotic kefir were determined in high-fat (HF) diet-fed C57BL/6J mice. EPS solutions showed rheological properties and lower viscosity compared to those of β-glucan (BG). EPS significantly suppressed the adipogenesis of 3T3-L1 preadipocytes in a dose-dependent manner. Mice were fed HF diets containing 5% EPS, 5% BG, 8% Res, or 5% microcrystalline cellulose (control) for 4 weeks. Compared with the control, EPS supplementation significantly reduced HF diet-induced body weight gain, adipose tissue weight, and plasma very-low-density lipoprotein cholesterol concentration (P < 0.05). Res and BG significantly reduced body weight gain; however, reduction in adipose tissue weight was not statistically significant, suggesting that the antiobesity effect of EPS occurs due to viscosity and an additional factor. EPS supplementation significantly enhanced abundance of Akkermansia spp. in feces. These data indicate that EPS shows significant antiobesity effects possibly via intestinal microbiota alterations.

Kefir Kültürünün Beyaz Peynir Yapımında Kullanılması Üzerine bir Araştırma

Directory of Open Access Journals (Sweden)

Hasan Yaygın

2015-02-01

Full Text Available Beyaz peynir yapımında kullanılacak saf kültürde yer alması gereken mikroorganizmaları saptamak amacı ile bazı çalışmalar yapılmıştır. Araştırıcıların çoğunluğu saf kültürde S. lactis, S. cremoris ve L. casei’ nin bulunması gerektiğini belirtmişlerdir. Bu çalışmada beyaz peynir yapımında saf kültür olarak kefir kültürü kullanılmıştır. Kefir kültüründe söz konusu bakterilerle beraber bazı maya ve bakteriler de bulunmaktadır. Araştırma sonuçları kefir kültürü katılan sütten yapılan beyaz peynirde asitlik gelişiminin istenilen düzeyde olduğu; tat ve aroma ile yapının tüketiciler tarafından beğenildiğini ortaya çıkarmıştır.

Thermal comfort in air-conditioned mosques in the dry desert climate

Energy Technology Data Exchange (ETDEWEB)

Al-ajmi, Farraj F. [Department of Civil Engineering, College of Technological Studies, Shuwaikh 70654 (Kuwait)

2010-11-15

In Kuwait, as in most countries with a typical dry desert climate, the summer season is long with a mean daily maximum temperature of 45 C. Centralized air-conditioning, which is generally deployed from the beginning of April to the end of October, can have tremendous impact on the amount of electrical energy utilized to mechanically control the internal environment in mosque buildings. The indoor air temperature settings for all types of air-conditioned buildings and mosque buildings in particular, are often calculated based on the analytical model of ASHRAE 55-2004 and ISO 7730. However, a field study was conducted in six air-conditioned mosque buildings during the summers of 2007 to investigate indoor climate and prayers thermal comfort in state of Kuwait. The paper presents statistical data about the indoor environmental conditions in Kuwait mosque buildings, together with an analysis of prayer thermal comfort sensations for a total of 140 subjects providing 140 sets of physical measurements and subjective questionnaires were used to collect data. Results show that the neutral temperature (T{sub n}) of the prayers is found to be 26.1 C, while that for PMV is 23.3 C. Discrepancy of these values is in fact about 2.8 C higher than those predicted by PMV model. Therefore, thermal comfort temperature in Kuwait cannot directly correlate with ISO 7730 and ASHRAE 55-2004 standards. Findings from this study should be considered when designing air conditioning for mosque buildings. This knowledge can contribute towards the development of future energy-related design codes for Kuwait. (author)

THERMAL POWER LOSS COMPENSATION IN THE PRODUCTION OF COOKED AND DRIED GRAINS WITH HEAT PUMPS USING

Directory of Open Access Journals (Sweden)

S. A. Shevtsov

2015-01-01

Full Text Available Using scientificand practical experience and analysis of recent innovative activity on modernization of food concentrates production, a new variant of the energy-efficient processing of cereal crops using superheated steam and direct involvement in the cooking and drying process waste energy using the vapor compression heat pump was suggested. A method for production of cereal concentrates, which is realized using microprocessor control of technological parameters. According to the information on the processes of cereals washing, cooking, drying and cooling microprocessor provides regime parameters control under the restrictions due to both yield of cooked and dried cereal of high quality and economic feasibility. At the same time the amount of moisture is continuously determined in the recirculation loop formed by the evaporation from the cereals in the drying process. To implement the proposed method of cooked and dried cereals production it is offered to use refrigerationand compressor unit operating in a heat pump mode. The refrigerant to be used is khladon 12V1 CF2ClBr with a boiling point in the evaporator of 4°C and the condensing temperature of 153.7 °C. The use of the heat pump in the heat supply system of cooked and dried cereals production instead of electric heaters will reduce power costs by 1.72 times. The proposed method for the production and control of technological parameters in the field of the product acceptable technological properties will provide high quality cooked and dried cereals; an increase in thermal efficiency by making full use of the waste heat of superheated steam; the reduction of specific energy consumption by 25-30 %; the creation of waste-free and environmentally friendly technologies for cereal production.

An Overt Chemical Protective Garment Reduces Thermal Strain Compared with a Covert Garment in Warm-Wet but Not Hot-Dry Environments

Directory of Open Access Journals (Sweden)

Matthew J. Maley

2017-11-01

Full Text Available Objectives: A commercial chemical, biological, radiological and nuclear (CBRN protective covert garment has recently been developed with the aim of reducing thermal strain. A covert CBRN protective layer can be worn under other clothing, with equipment added for full chemical protection when needed. However, it is unknown whether the covert garment offers any alleviation to thermal strain during work compared with a traditional overt ensemble. Therefore, the aim of this study was to compare thermal strain and work tolerance times during work in an overt and covert ensemble offering the same level of CBRN protection.Methods: Eleven male participants wore an overt (OVERT or covert (COVERT CBRN ensemble and walked (4 km·h−1, 1% grade for a maximum of 120 min in either a wet bulb globe temperature [WBGT] of 21, 30, or 37°C (Neutral, WarmWet and HotDry, respectively. The trials were ceased if the participants' gastrointestinal temperature reached 39°C, heart rate reached 90% of maximum, walking time reached 120 min or due to self-termination.Results: All participants completed 120 min of walking in Neutral. Work tolerance time was greater in OVERT compared with COVERT in WarmWet (P < 0.001, 116.5[9.9] vs. 88.9[12.2] min, respectively, though this order was reversed in HotDry (P = 0.003, 37.3[5.3] vs. 48.4[4.6] min, respectively. The rate of change in mean body temperature and mean skin temperature was greater in COVERT (0.025[0.004] and 0.045[0.010]°C·min−1, respectively compared with OVERT (0.014[0.004] and 0.027[0.007]°C·min−1, respectively in WarmWet (P < 0.001 and P = 0.028, respectively. However, the rate of change in mean body temperature and mean skin temperature was greater in OVERT (0.068[0.010] and 0.170[0.026]°C·min−1, respectively compared with COVERT (0.059[0.004] and 0.120[0.017]°C·min−1, respectively in HotDry (P = 0.002 and P < 0.001, respectively. Thermal sensation, thermal comfort, and ratings of perceived

Full scale experimental study of a small natural draft dry cooling tower for concentrating solar thermal power plant

International Nuclear Information System (INIS)

Li, Xiaoxiao; Duniam, Sam; Gurgenci, Hal; Guan, Zhiqiang; Veeraragavan, Anand

2017-01-01

Highlights: • A 20 m high natural draft dry cooling tower is designed and tested. • The cooling tower model is refined and validated with the experimental data. • The performance of the cooling tower utilized in a CST power plant is investigated. • Ambient temperature effect on Rankine cycle and Brayton cycle is discussed. - Abstract: Concentrating solar thermal power system can provide low carbon, renewable energy resources in countries or regions with strong solar irradiation. For this kind of power plant which is likely to be located in the arid area, natural draft dry cooling tower is a promising choice. To develop the experimental studies on small cooling tower, a 20 m high natural draft dry cooling tower with fully instrumented measurement system was established by the Queensland Geothermal Energy Centre of Excellence. The performance of this cooling tower was measured with the constant heat input of 600 kW and 840 kW and with ambient temperature ranging from 20 °C to 32 °C. The cooling tower numerical model was refined and validated with the experimental data. The model of 1 MW concentrating solar thermal supercritical CO_2 power cycle was developed and integrated with the cooling tower model. The influences of changing ambient temperature and the performance of the cooling tower on efficiency of the power system were simulated. The differences of the mechanism of the ambient temperature effect on Rankine cycle and supercritical CO_2 Brayton cycle were analysed and discussed.

All-dry transferred single- and few-layer MoS2 field effect transistor with enhanced performance by thermal annealing

Science.gov (United States)

Islam, Arnob; Lee, Jaesung; Feng, Philip X.-L.

2018-01-01

We report on the experimental demonstration of all-dry stamp transferred single- and few-layer (1L to 3L) molybdenum disulfide (MoS2) field effect transistors (FETs), with a significant enhancement of device performance by employing thermal annealing in moderate vacuum. Three orders of magnitude reduction in both contact and channel resistances have been attained via thermal annealing. We obtain a low contact resistance of 22 kΩ μm after thermal annealing of 1L MoS2 FETs stamp-transferred onto gold (Au) contact electrodes. Furthermore, nearly two orders of magnitude enhancement of field effect mobility are also observed after thermal annealing. Finally, we employ Raman and photoluminescence measurements to reveal the phenomena of alloying or hybridization between 1L MoS2 and its contacting electrodes during annealing, which is responsible for attaining the low contact resistance.

Thermal inactivation of H5N2 high-pathogenicity avian influenza virus in dried egg white with 7.5% moisture.

Science.gov (United States)

Thomas, Colleen; Swayne, David E

2009-09-01

High-pathogenicity avian influenza viruses (HPAIV) cause severe systemic disease with high mortality in chickens. Isolation of HPAIV from the internal contents of chicken eggs has been reported, and this is cause for concern because HPAIV can be spread by movement of poultry products during marketing and trade activity. This study presents thermal inactivation data for the HPAIV strain A/chicken/PA/1370/83 (H5N2) (PA/83) in dried egg white with a moisture content (7.5%) similar to that found in commercially available spray-dried egg white products. The 95% upper confidence limits for D-values calculated from linear regression of the survival curves at 54.4, 60.0, 65.5, and 71.1 degrees C were 475.4, 192.2, 141.0, and 50.1 min, respectively. The line equation y = [0.05494 x degrees C] + 5.5693 (root mean square error = 0.0711) was obtained by linear regression of experimental D-values versus temperature. Conservative predictions based on the thermal inactivation data suggest that standard industry pasteurization protocols would be very effective for HPAIV inactivation in dried egg white. For example, these calculations predict that a 7-log reduction would take only 2.6 days at 54.4 degrees C.

Method and apparatus for in-situ drying investigation and optimization of slurry drying methodology

Science.gov (United States)

Armstrong, Beth L.; Daniel, Claus; Howe, Jane Y.; Kiggans, Jr, James O.; Sabau, Adrian S.; Wood, III, David L.; Kalnaus, Sergiy

2016-05-10

A method of drying casted slurries that includes calculating drying conditions from an experimental model for a cast slurry and forming a cast film. An infrared heating probe is positioned on one side of the casted slurry and a thermal probe is positioned on an opposing side of the casted slurry. The infrared heating probe may control the temperature of the casted slurry during drying. The casted slurry may be observed with an optical microscope, while applying the drying conditions from the experimental model. Observing the casted slurry includes detecting the incidence of micro-structural changes in the casted slurry during drying to determine if the drying conditions from the experimental model are optimal.

Application of culture-dependent and culture-independent methods for the identification of Lactobacillus kefiranofaciens in microbial consortia present in kefir grains.

Science.gov (United States)

Hamet, Maria Fernanda; Londero, Alejandra; Medrano, Micaela; Vercammen, Elisabeth; Van Hoorde, Koenraad; Garrote, Graciela L; Huys, Geert; Vandamme, Peter; Abraham, Analía G

2013-12-01

The biological and technological characteristics of kefiran as well as its importance in grain integrity led us to analyze the microbial kefir grain consortium with focus on Lactobacillus kefiranofaciens. The presence of L. kefiranofaciens in the nine kefir grains studied was demonstrated by denaturing gradient gel electrophoresis. By culture dependent methods applying a methodology focused on the search of this species, 22 isolates with typical morphology were obtained and identified applying a combination of SDS-PAGE of whole cell proteins, (GTG)5-PCR and sequence analysis of the housekeeping gene encoding the α-subunit of bacterial phenylalanyl-tRNA synthase (pheS). This polyphasic approach allowed the reliable identification of 11 L. kefiranofaciens, 5 Lactobacillus paracasei, 4 Lactobacillus kefiri and 2 Lactobacillus parakefiri isolates. Isolated L. kefiranofaciens strains produced polysaccharide in strain-dependent concentrations and EPS produced by them also differed in the degree of polymerization. The isolation and accurate identification of L. kefiranofaciens is relevant taking into account the important role of this microorganism in the grain ecosystem as well as its potential application as starter in food fermentations. Copyright © 2013 Elsevier Ltd. All rights reserved.

Dry process potentials

International Nuclear Information System (INIS)

Faugeras, P.

1997-01-01

Various dry processes have been studied and more or less developed in order particularly to reduce the waste quantities but none of them had replaced the PUREX process, for reasons departing to policy errors, un-appropriate demonstration examples or too late development, although realistic and efficient dry processes such as a fluoride selective volatility based processes have been demonstrated in France (CLOVIS, ATILA) and would be ten times cheaper than the PUREX process. Dry processes could regain interest in case of a nuclear revival (following global warming fears) or thermal wastes over-production. In the near future, dry processes could be introduced in complement to the PUREX process, especially at the end of the process cycle, for a more efficient recycling and safer storage (inactivation)

Microwave wood strand drying: energy consumption, VOC emission and drying quality

Energy Technology Data Exchange (ETDEWEB)

Wang, S.; Du, G.; Zhang, Y. [Tennessee Univ., Knoxville, TN (United States). Dept. of Forestry, Wildlife and Fisheries

2005-07-01

The objective of this research was to develop microwave drying technology for wood strand drying for oriented strand board (OSB) manufacturing. The advantages of microwave drying included a reduction in the drying time of wood strands and a reduction in the release of volatile organic compounds (VOC) through a decrease in the thermal degradation of the wood material. Temperature and moisture content changes under different microwave drying conditions were investigated. The effects of microwave drying on VOC emissions were evaluated and analyzed using gas chromatography and mass spectrometry. Microwave power input and the mass of drying materials in the microwave oven were found to have a dominant effect on drying quality. Results indicated that an increase in microwave power input and a decrease in sample weights resulted in high drying temperatures, short drying times and a high drying rate. The effect of microwave drying on the strand surfaces was also investigated. Different strand geometries and initial moisture content resulted in varying warm-up curves, but did not influence final moisture content. VOC emissions were quantified by comparing alpha-pinene concentrations. The microwave drying resulted in lower VOC emissions compared with conventional drying methods. It was concluded that the microwave drying technique provided faster strand drying and reduced energy consumption by up to 50 per cent. In addition, the surface wettability of wood strands dried with microwaves was better than with an industrial rotary drum drier. 12 refs., 3 tabs., 5 figs.

Effect of baking and steaming on physicochemical and thermal properties of sweet potato puree preserved by freezing and freeze-drying

Directory of Open Access Journals (Sweden)

Bernarda Svrakačić

2016-01-01

Full Text Available Thermal treatments could be one of the hurdles in applications of sweet potato purees for food different products formulation. Sweet potato purees (SPP were prepared from raw, baked and steamed roots and they were preserved by freezing and freeze-drying. The effects of baking and steaming on thermal properties (melting temperature-Tm, melting transition energy - ΔH, and glass transition temperatures - Tg of sweet potato (cultivar Beauregard, were measured by means of a Differential scanning calorimetry (DSC. The SPP made from baked roots had higher total and soluble solids (20.32 and 18.95%, respectively than SPP made from raw and steamed roots. It can be also noticed that starch content was reduced by steaming and baking which reflected on amount of total and reducing sugars. The increase of reducing sugars level in baked SPP for 3.78% and steamed for 0.86% SPP was the result of yielding the maltose. The chemical changes of SPP also influenced the thermal behavior such that SPP prepared from baked sweet potato roots had the lowest initial freezing point (-2.80 °C followed by SPP prepared from steamed (-2.63 °C and raw (-0.71 °C roots. The highest energy for melting (transition was needed for SPP prepared from raw potato roots followed by steamed and baked roots, -103.79, -103.63, and -102.90 J/g, respectively. The glass transition in freeze-dried SPP prepared from raw roots was not detected. However, in the freeze-dried SPP prepared from baked and steamed roots the glass transition was detected in the range of 39 and 42 °C but with no significant difference (p > 0.05.

Physicochemical properties of exopolysaccharide produced by Lactobacillus kefiranofaciens ZW3 isolated from Tibet kefir.

Science.gov (United States)

Wang, Yanping; Ahmed, Zaheer; Feng, Wu; Li, Chao; Song, Shiying

2008-10-01

An exopolysaccharide (EPS) producing strain, ZW3, was isolated from Tibet kefir grain and was identified as Lactobacillus kefiranofaciens. FT-IR spectroscopy revealed the presence of carboxyl, hydroxyl, and amide groups, which correspond to a typical heteropolymeric polysaccharide. The GC analysis of ZW3 EPS revealed that it was glucogalactan in nature. Exopolymer showed similar flocculation stability like xanthan gum but better than guar gum with a melting point of 93.38 degrees C which is lower than xanthan gum (153.4 degrees C) and guar gum (490.11 degrees C). Compared with other commercially available hydrocolloids like xanthan gum, guar gum and locust gum ZW3 EPS showed much better emulsifying capability.

Heat and mass transfer models to understand the drying mechanisms of a porous substrate.

Science.gov (United States)

Songok, Joel; Bousfield, Douglas W; Gane, Patrick A C; Toivakka, Martti

2016-02-01

While drying of paper and paper coatings is expensive, with significant energy requirements, the rate controlling mechanisms are not currently fully understood. Two two-dimensional models are used as a first approximation to predict the heat transfer during hot air drying and to evaluate the role of various parameters on the drying rates of porous coatings. The models help determine the structural limiting factors during the drying process, while applying for the first time the recently known values of coating thermal diffusivity. The results indicate that the thermal conductivity of the coating structure is not the controlling factor, but the drying rate is rather determined by the thermal transfer process at the structure surface. This underlines the need for ensuring an efficient thermal transfer from hot air to coating surface during drying, before considering further measures to increase the thermal conductivity of porous coatings.

Validation study of FLUENT for the application of dry-storage system thermal analysis

International Nuclear Information System (INIS)

Tseng Yungshin; Wang Jongrong; Cheng Yihsiang; Shih Chunkuan

2009-01-01

In this study, the commercial CFD code, FLUENT, has been selected to evaluate the accuracy of the temperature prediction for nuclear fuel dry storage system (DSS). The experimental results of VSC-17 DSS were employed for such purposes. Through a minimal assumptions and necessary simplifications (e.g., the lumped model of fuel), a high integrity geometry model with about 4.0 million meshes was employed to solve the conjugate heat transfer coupled with thermal radiation problem. First, the general scheme validation indicates that FLUENT can provide a result which agrees well with analytical solution. It means that the numerical scheme included in FLUENT is reliable and accurate. The comparisons with VSC-17 further points out that the maximum temperature difference between simulation and experimental solution is less than 10degC and the maximum deviation for whole DSS is less than 5%. Those findings mentioned above imply that FLUENT can be a highly accurate thermal analysis tool for d DSS design. Through a series modeling and scheme selecting, this code can be an efficient tool for the new DSS development in the future. (author)

Measurements of thermal properties of rocks

International Nuclear Information System (INIS)

Kumada, Toshiaki

2001-02-01

The report concerns the measurement of thermal conductivity and specific heat of supplied sedimental rock B and Funyu rock. The method of measurement of these properties was done with the method which was developed at 1997 and improved much in its accuracy by the present author et al. The porosity of sedimental rock B is 0.55, which is deduced from the density of rock (the porosity deduced from the difference between dry and water filled conditions is 0.42) and the shape and size of pores in rock are much different. Its thermal conductivity is 0.238 W/mK in dry and 1.152 W/mK in water filled conditions respectively, while the thermal conductivity of bentonite is 0.238 W/mK in dry and 1.152 W/mK in water saturated conditions. The difference of thermal conductivity between dry and water saturated conditions is little difference in sedimental rock B and bentonite at same porosity. The porosity of Funyu rock is 0.26 and the shape and size of pores in the rock are uniform. Its thermal conductivity is 0.914 W/mK in dry and 1.405 W/mK in water saturated conditions, while the thermal conductivity of bentonite is 0.606 W/mK in dry and 1.591 W/mK in water saturated conditions respectively. The correlation estimating thermal conductivity of rocks was derived based on Fricke correlation by presuming rocks as a suspension. (author)

Mechanical performance and thermal stability of glass fiber reinforced silica aerogel composites based on co-precursor method by freeze drying

Science.gov (United States)

Zhou, Ting; Cheng, Xudong; Pan, Yuelei; Li, Congcong; Gong, Lunlun; Zhang, Heping

2018-04-01

In order to maintain the integrity, glass fiber (GF) reinforced silica aerogel composites were synthesized using methltrimethoxysilane (MTMS) and water glass co-precursor by freeze drying method. The composites were characterized by scanning electron microscopy, Brunauer-Emmett-Teller analysis, uniaxial compressive test, three-point bending test, thermal conductivity analysis, contact angle test, TG-DSC analysis. It was found that the molar ratio of MTMS/water glass could significantly affect the properties of composites. The bulk density and thermal conductivity first decreased and then increased with the increasing molar ratio. The composites showed remarkable mechanical strength and flexibility compared with pure silica aerogel. Moreover, when the molar ratio is 1.8, the composites showed high specific surface area (870.9 m2/g), high contact angle (150°), great thermal stability (560 °C) and low thermal conductivity (0.0248 W/m·K). These outstanding properties indicate that GF/aerogels have broad prospects in the field of thermal insulation.

Solar thermal drum drying performance of prune and tomato pomaces

Science.gov (United States)

Fruit and vegetable pomaces are co-products of the food processing industry; they are underutilized in part because their high water activity (aw) renders them unstable. Drum drying is one method that can dry/stabilize pomaces, but current drum drying methods utilize conventional, high-environmental...

Fine structure of Tibetan kefir grains and their yeast distribution, diversity, and shift.

Directory of Open Access Journals (Sweden)

Man Lu

Full Text Available Tibetan kefir grains (TKGs, a kind of natural starter for fermented milk in Tibet, China, host various microorganisms of lactic acid bacteria, yeasts, and occasionally acetic acid bacteria in a polysaccharide/protein matrix. In the present study, the fine structure of TKGs was studied to shed light on this unusual symbiosis with stereomicroscopy and thin sections. The results reveal that TKGs consist of numerous small grain units, which are characterized by a hollow globular structure with a diameter between 2.0 and 9.0 mm and a wall thickness of approximately 200 µm. A polyhedron-like net structure, formed mainly by the bacteria, was observed in the wall of the grain units, which has not been reported previously to our knowledge. Towards the inside of the grain unit, the polyhedron-like net structures became gradually larger in diameter and fewer in number. Such fine structures may play a crucial role in the stability of the grains. Subsequently, the distribution, diversity, and shift of yeasts in TKGs were investigated based on thin section, scanning electron microscopy, cloning and sequencing of D1/D2 of the 26S rRNA gene, real-time quantitative PCR, and in situ hybridization with specific fluorescence-labeled oligonucleotide probes. These show that (i yeasts appear to localize on the outer surface of the grains and grow normally together to form colonies embedded in the bacterial community; (ii the diversity of yeasts is relatively low on genus level with three dominant species--Saccharomyces cerevisiae, Kluyveromyces marxianus, and Yarrowia lipolytica; (iii S. cerevisiae is the stable predominant yeast species, while the composition of Kluyveromyces and Yarrowia are subject to change over time. Our results indicate that TKGs are relatively stable in structure, and culture conditions to some extent shape the microbial community and interaction in kefir grains. These findings pave the way for further study of the specific symbiotic

Fine Structure of Tibetan Kefir Grains and Their Yeast Distribution, Diversity, and Shift

Science.gov (United States)

Lu, Man; Wang, Xingxing; Sun, Guowei; Qin, Bing; Xiao, Jinzhou; Yan, Shuling; Pan, Yingjie; Wang, Yongjie

2014-01-01

Tibetan kefir grains (TKGs), a kind of natural starter for fermented milk in Tibet, China, host various microorganisms of lactic acid bacteria, yeasts, and occasionally acetic acid bacteria in a polysaccharide/protein matrix. In the present study, the fine structure of TKGs was studied to shed light on this unusual symbiosis with stereomicroscopy and thin sections. The results reveal that TKGs consist of numerous small grain units, which are characterized by a hollow globular structure with a diameter between 2.0 and 9.0 mm and a wall thickness of approximately 200 µm. A polyhedron-like net structure, formed mainly by the bacteria, was observed in the wall of the grain units, which has not been reported previously to our knowledge. Towards the inside of the grain unit, the polyhedron-like net structures became gradually larger in diameter and fewer in number. Such fine structures may play a crucial role in the stability of the grains. Subsequently, the distribution, diversity, and shift of yeasts in TKGs were investigated based on thin section, scanning electron microscopy, cloning and sequencing of D1/D2 of the 26S rRNA gene, real-time quantitative PCR, and in situ hybridization with specific fluorescence-labeled oligonucleotide probes. These show that (i) yeasts appear to localize on the outer surface of the grains and grow normally together to form colonies embedded in the bacterial community; (ii) the diversity of yeasts is relatively low on genus level with three dominant species – Saccharomyces cerevisiae, Kluyveromyces marxianus, and Yarrowia lipolytica; (iii) S. cerevisiae is the stable predominant yeast species, while the composition of Kluyveromyces and Yarrowia are subject to change over time. Our results indicate that TKGs are relatively stable in structure, and culture conditions to some extent shape the microbial community and interaction in kefir grains. These findings pave the way for further study of the specific symbiotic associations between S

Thermoelectrical and thermal analyses of copper(II) acetate monohydrate ZnO-matrix composite powder obtained by freeze-drying

International Nuclear Information System (INIS)

Bellini, Jusmar Valentin; Pineda, Edgardo Alfonso Gomez; Rocha, Raquel de Almeida; Ponzoni, Andre Luis de Lima; Paesano, Andrea

2006-01-01

The thermal history of freeze-dried mixtures of composite powders containing ZnO-matrix and (CH 3 COO) 2 Cu.H 2 O (copper(II) acetate monohydrate) was undertaken by thermal analysis (TA) coupled to thermoelectrical analysis (TEA). Experiments were carried out on compacted samples, under non-isothermal conditions, in air, up to 350 deg. C, by measuring the electrical resistance during heating, called thermoelectrical resistometry (TER), and by differential scanning calorimetry (DSC). Activation energy (E a ) for exothermal events related to the decomposition of (CH 3 COO) 2 Cu (copper(II) acetate, CuAc 2 ), observed within the range 225-325 deg. C, was estimated according to ASTM E 698 method. Values of E a equal to 154 and 155 kJ/mol were obtained by TER and DSC, respectively. TER showed that the thermal decomposition of CuAc 2 involves the liberation of electrons. Results also indicated that TER may be used as an alternative or complementary method for the study of the thermal decomposition mechanisms of transition metal(II) acetates

Latest Apple Drying Technologies: A Review

OpenAIRE

ÖZDEMİR, Yasin; SAYIN, Emir Olcay; KURULTAY, Şefik

2009-01-01

Drying is known as one of the oldest preservation methods and can be applicable to many fruits. Sun drying of apple has been known from ancient times. However, this technique is weather-dependent and has contamination problems such as dust, soil, sand particles and insects. Hot air drying of apples has low energy efficiency and requires longer drying period. The desire to eliminate these problems, prevent quality loss, and achieve fast and effective thermal processing has resulted in an incre...

Drying effects on the antioxidant properties of tomatoes and ginger.

Science.gov (United States)

Gümüşay, Özlem Aktürk; Borazan, Alev Akpınar; Ercal, Nuran; Demirkol, Omca

2015-04-15

In this study, the effects of four different drying processes, sun drying (SD), oven drying (OD), vacuum oven drying (VOD) and freeze drying (FD) for tomatoes (Solanum lycopersicum) and ginger (Zingiber officinale) in terms of thiolic and phenolic contents have been studied. Thiol content, total phenolic content (TPC), ascorbic acid (AA) content, and cupric ion reducing antioxidant capacity (CUPRAC) were determined in fresh and dried samples. Glutathione (GSH) and cysteine (Cys) were determined as the thiol contents of tomatoes and ginger. Significant losses were observed in the contents of TPC, AA, GSH and Cys and CUPRAC values in all samples that were dried using the thermal method. There was a statistically significant difference in the losses of the TPC, AA, and thiol contents between the use of thermal drying and freeze drying (except Cys in tomatoes) methods. Freeze dried tomato and ginger samples have been found to have better antioxidant properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

Absence of storage effects on radiation damage after thermal neutron irradiation of dry rice seeds

Energy Technology Data Exchange (ETDEWEB)

Kowyama, Y. [Mie Univ., Tsu (Japan); Saito, M.; Kawase, T.

1987-09-15

Storage effects on dry rice seeds equilibrated to 6.8% moisture content were examined after irradiation with X-rays of 5, 10, 20 and 40 kR and with thermal neutrons of 2.1, 4.2, 6.3 and 8.4×10{sup 13}N{sub th}/cm{sup 2}. Reduction in root growth was estimated from dose response curves after storage periods of 1 hr to 21 days. The longer the storage period, the greater enhancement of radiation damages in X-irradiated seeds. There were two components in the storage effect, i. e., a rapid increase of radiosensitivity within the first 24 hr and a slow increase up to 21 days. An almost complete absence of a storage effect was observed after thermal neutron exposure, in spite of considerably high radioactivities of the induced nuclides, {sup 56}Mn, {sup 42}K and {sup 24}Na, which were detected from gamma-ray spectrometry of the irradiated seeds. The present results suggest that the contributions of gamma-rays from the activated nuclides and of inherent contaminating gamma-rays are little or negligible against the neutron-induced damage, and that the main radiobiological effects of thermal neutrons are ascribed to in situ radiations, i, e., heavy particles resulting from neutron-capture reaction of atom. A mechanism underlying the absence of storage effect after thermal neutron irradiation was briefly discussed on the basis of radical formation and decay. (author)

A Radiochemical Biotechnological Approach: Preliminary Study of Lactose Uptake Rate by Kefir Cells, Using 14C-labeled Lactose, in Anaerobic Fermentation

Science.gov (United States)

Golfinopoulos, A.; Soupioni, M.; Kanellaki, M.; Koutinas, A. A.

2008-08-01

The effect of initial lactose concentration on lactose uptake rate by kefir free cells, during the lactose fermentation, was studied in this work. For the investigation 14C-labelled lactose was used due to the fact that labeled and unlabeled molecules are fermented in the same way. The results illustrated lactose uptake rates are about up to two fold higher at lower initial ∘Bé densities as compared with higher initial ∘Bé densities.

A full size test rig of dry and dry-wet towers

International Nuclear Information System (INIS)

Fesson, J.-P.

1981-01-01

In order to test the various systems submitted by French companies, with a view to their application to the 900 MW and 1300 MW nuclear units, the tower is divided into two parts, each permitting the evacuation of an identical thermal charge. The first part includes a cross-current wet zone in which the water flows vertically and the air horizontally, connected to a set of vertical dry batteries. The second part includes bands of packing along the counter-current system, alternating with horizontal dry exchangers [fr

Investigation of pre-drying lignite in an existing Greek power plant

Directory of Open Access Journals (Sweden)

Agraniotis Michalis

2012-01-01

Full Text Available The application of lignite pre-drying technologies in next generation of lignite power plants by utilizing low pressure steam as a drying medium instead of hot recirculated flue gas - combined with thermal utilization of the vaporized coal moisture - is expected to bring efficiency increase of 2-4 percentage points in future lignite power plants compared with today’s state of the art. The pre-drying concept is of particular importance in Greek boilers firing lignite with a high water and ash content. The combustion of Greek predried lignite has been investigated experimentally and via numerical simulations in our previous research. This study focuses on the potential integration of a lignite pre-drying system in an existing Greek power plant with dry lignite co-firing thermal share of up to 30%. The radiative and convective heat fluxes to the boiler and the overall boiler heat balance is calculated for reference and dry lignite co-firing conditions by an in-house calculation code. The overall plant’s thermal cycle is then simulated using commercial thermal cycle calculation software. The net plant efficiency is in this way determined for reference and dry coal co-firing conditions. According to the simulation results the integration of a pre-drying system and the implementation of dry lignite co-firing may bring an efficiency increase of about 1.5 percentage points in existing Greek boilers. It is therefore considered as an important measure towards improving plant efficiency and reducing specific CO2 emissions in existing plants.

Synthesis of platinum nanoparticles using dried Anacardium occidentale leaf and its catalytic and thermal applications.

Science.gov (United States)

Sheny, D S; Philip, Daizy; Mathew, Joseph

2013-10-01

An environment friendly approach for the synthesis of Pt nanoparticles (NPs) using dried leaf powder of Anacardium occidentale is reported. The formation of Pt NPs is monitored using UV-Vis spectrophotometer. FTIR spectra reveal that proteins are bound to Pt nanoparticles. TEM images show irregular rod shaped particles which are crystalline. The quantity of leaf powder plays a vital role in determining the size of particles. Synthesized NPs exhibit good catalytic activity in the reduction of aromatic nitrocompound. The effective thermal conductivity of synthesized Pt/water nanofluid has been measured and found to be enhanced to a good extent. Copyright © 2013 Elsevier B.V. All rights reserved.

Rodigo Uno (Italy) geothermal thermal energy for crop drying

International Nuclear Information System (INIS)

Facchini, U.; Sordelli, C.; Magnoni, S.; Cantadori, M.

1992-01-01

This paper outlines the chief design and performance features of a forage drying installation which makes use of locally available geothermal energy. The heat exchange is accomplished through a water-air exchanger directly fed by 59 degrees C geothermal springs. Two 80,000 cubic meter/hour ventilators, making use of this energy (58 to 38 degrees C heat exchange), raise the drying air temperature by 16 degrees C, while providing an overall drying capacity of 43,200 kg/day. The balance of available 38 degrees C geothermal energy is being employed by a local aquaculture farm. The paper comments on the economic and environmental benefits being derived from this direct utilization of geothermal energy

Dry-type cooling systems in electric power production

International Nuclear Information System (INIS)

Li, K.W.

1973-01-01

This study indicates that the dry-type cooling tower could be adopted in this country as an alternative method for removing waste heat from power plants. The use of dry cooling towers would not only lead to a change of cooling system design, but also to a change of overall thermal design in a power generating system. The principal drawbacks to using dry cooling towers in a large steam-turbine plant are the generating capacity loss, increased fuel consumption and the high capital cost of the dry cooling towers. These economic penalties must be evaluated in each specific case against the benefits that may result from the use of dry cooling towers. The benefits are principally these: (1) Fewer constraints in the selection of power plant sites, (2) No thermal discharge to the natural water bodies, (3) Elimination of vapor plumes and water evaporation loss, and (4) Freedom of adding new units to an existing facility where inadequate water supply may otherwise rule out this possibility

A Radiochemical Biotechnological Approach: Preliminary Study of Lactose Uptake Rate by Kefir Cells, Using 14C-labeled Lactose, in Anaerobic Fermentation

International Nuclear Information System (INIS)

Golfinopoulos, A.; Soupioni, M.; Kanellaki, M.; Koutinas, A. A.

2008-01-01

The effect of initial lactose concentration on lactose uptake rate by kefir free cells, during the lactose fermentation, was studied in this work. For the investigation 14 C-labelled lactose was used due to the fact that labeled and unlabeled molecules are fermented in the same way. The results illustrated lactose uptake rates are about up to two fold higher at lower initial (convolution sign)Be densities as compared with higher initial (convolution sign)Be densities

Lactobacillus kefiranofaciens M1 isolated from milk kefir grains ameliorates experimental colitis in vitro and in vivo.

Science.gov (United States)

Chen, Y P; Hsiao, P J; Hong, W S; Dai, T Y; Chen, M J

2012-01-01

Lactobacillus kefiranofaciens M1, isolated from and identified in Taiwanese milk kefir grain, has demonstrated immune-modulating activity. In the present study, we further investigated the effects of Lb. kefiranofaciens M1 on intestinal epithelial cells in vitro and on dextran sodium sulfate (DSS)-induced colitis in vivo. The possible mechanisms regarding the cytokine products and intestinal epithelial barrier restoration as well as the putative receptor for the protective effects of Lb. kefiranofaciens M1 were investigated. In vitro results indicated that Lb. kefiranofaciens M1 could strengthen the epithelial barrier function in vitro by increasing the transepithelial electrical resistance (TEER) and significantly upregulated the level of the chemokine CCL-20 at both the apical and basolateral sites. The in vivo effects of Lb. kefiranofaciens M1 on the regulation of intestinal physiology indicate that this strain could ameliorate DSS-induced colitis with a significant attenuation of the bleeding score and colon length shortening. Production of proinflammatory cytokines was decreased and that of the antiinflammatory cytokine IL-10 was increased in the DSS-treated mice given Lb. kefiranofaciens M1. The putative receptor for the protective effects of Lb. kefiranofaciens M1 was toll-like receptor 2 (TLR2), which was involved in probiotic-induced cytokine production in vitro and in attenuation of the bleeding score and colon length shortening in vivo. In this study, the kefir lactobacillus Lb. kefiranofaciens M1 clearly demonstrated an anticolitis effect. Based on these results, Lb. kefiranofaciens M1 has the potential to be applied in fermented dairy products as an alternative therapy for intestinal disorders. Copyright © 2012 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Effect of drying methods on total antioxidant capacity of bitter gourd (momordica charantia) fruit

Science.gov (United States)

Tan, Ee Shian; Abdullah, Aminah; Maskat, Mohammad Yusof

2013-11-01

The effect of thermal and non-thermal drying methods on hydrophilic and lipophilic antioxidant capacities of bitter gourd fruit was investigated in this study. The bitter gourd fruits were dried by following methods: (i) oven drying 40°C, (ii) oven drying 50°C, (iii) oven drying 60°C, (iv) microwave drying (medium low power), (v) microwave drying (medium power) and (vi) freeze drying. Pure acetone and hexane were used to extract the hydrophilic and lipophilic antioxidant compounds from dried bitter gourd fruits. Freeze dried extracts reported to have highest values in DPPH scavenging activity (hydrophilic and lipophilic fractions), FRAP (lipophilic fraction) and TPC (hydrophilic and lipophilic fraction). Thermal drying slightly increased the values of DPPH scavenging activity, FRAP and TPC assays for hydrophilic extracts. Results concluded bitter gourd fruit is a good source of natural antioxidants and its total antioxidant quality was most preserved by freeze drying. Additionally, the higher value reported in DPPH scavenging activity, FRAP and TPC assays for lipophilic extracts than the hydrophilic extracts suggested that the lipophilic antioxidant compounds of bitter gourd fruit might possess stronger antioxidant power than its counterpart.

Study of Energy Consumption of Potato Slices During Drying Process

Directory of Open Access Journals (Sweden)

Hafezi Negar

2015-06-01

Full Text Available One of the new methods of food drying using infrared heating under vacuum is to increase the drying rate and maintain the quality of dried product. In this study, potato slices were dried using vacuum-infrared drying. Experiments were performed with the infrared lamp power levels 100, 150 and 200 W, absolute pressure levels 20, 80, 140 and 760 mmHg, and with three thicknesses of slices 1, 2 and 3 mm, in three repetitions. The results showed that the infrared lamp power, absolute pressure and slice thickness have important effects on the drying of potato. With increasing the radiation power, reducing the absolute pressure (acts of vacuum in the dryer chamber and also reducing the thickness of potato slices, drying time and the amount of energy consumed is reduced. In relation to thermal utilization efficiency, results indicated that with increasing the infrared radiation power and decreasing the absolute pressure, thermal efficiency increased.

Effects of Lactobacillus kefiranofaciens M1 isolated from kefir grains on enterohemorrhagic Escherichia coli infection using mouse and intestinal cell models.

Science.gov (United States)

Chen, Y P; Lee, T Y; Hong, W S; Hsieh, H H; Chen, M J

2013-01-01

A potential probiotic strain, Lactobacillus kefiranofaciens M1, was previously isolated from kefir grains, which are used to manufacture the traditional fermented drink kefir. The aim of this study was to investigate the effects of Lb. kefiranofaciens M1 on enterohemorrhagic Escherichia coli (EHEC) infection, using mice and intestinal cell models. BALB/c mice were daily administrated with either phosphate buffered saline or Lb. kefiranofaciens M1 at 2×10(8) cfu/mouse per day intragastrically for 7 d. Intragastric challenges with EHEC (2×10(9) cfu/mouse) were conducted on d 0, 4, and 7 after treatment. Administration of Lb. kefiranofaciens M1 was able to prevent EHEC infection-induced symptoms, intestinal damage, renal damage, bacterial translocation, and Shiga toxin penetration. Furthermore, the mucosal EHEC-specific IgA responses were increased after Lb. kefiranofaciens M1 administration in the EHEC-infected mouse system. Additionally, in vitro, Lb. kefiranofaciens M1 was shown to have a protective effect on Caco-2 intestinal epithelial cells and Caco-2 intestinal epithelial cell monolayers; the bacteria limited EHEC-induced cell death and reduced the loss of epithelial integrity. These findings support the potential of Lb. kefiranofaciens M1 treatment as an approach to preventing EHEC infection and its effects. Copyright © 2013 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

Assessment of thermal load on transported goats administered with ascorbic acid during the hot-dry conditions

Science.gov (United States)

Minka, N. S.; Ayo, J. O.

2012-03-01

The major factor in the induction of physiological stress during road transportation of livestock is the complex fluctuations of the thermal transport microenvironment, encountered when animals are transported across different ecological zones. Recommended guidelines on optimum "on-board" conditions in which goats should be transported are lacking, and there are no acceptable ranges and limits for the thermal loads to which goats may be subjected during long-distance road transportation in hot-dry conditions. Panting score (PS), rectal temperature (RT), heart rate (HR) and respiratory rate (RR) were employed as reliable stress indices to assess the effects of different thermal loads, measured as temperature humidity index (THI), encountered in the vehicle during 12 h of road transportation of 40 goats, and to suggest the administration of 100 mg/kg body weight of ascorbic acid (AA) as an ameliorating agent. The results obtained showed that the PS, RT, HR and RR rose above normal reference values with increase in the THI and journey duration. The rise in PS value, which is a visual indicator of the severity of thermal load, was the most pronounced. The results suggest that values of THI in the vehicle up to 94.6 constitute no risk, while at of 100 it presents a moderate risk and above 100 may result in severe stress. The relationships between the thermal load and the physiological variables were positive and significant ( P goats. The results demonstrated that administration of 100 mg/kg body weight of AA before road transportation mitigated the risk of adverse effects of high THI values and other stress factors due to road transportation in goats.

Drying characteristics and engineering properties of fermented ...

African Journals Online (AJOL)

STORAGESEVER

2009-03-06

Mar 6, 2009 ... fermented ground cassava. J. T. Nwabanne ... The drying characteristics of fermented ground local variety of ... effect of variety on the drying and engineering properties of fermented .... Figure 2 shows that the bulk density of each cultivar ... very close thermal conductivities as depicted in the shape of Figure ...

Recent advances in fluidized bed drying

Science.gov (United States)

Haron, N. S.; Zakaria, J. H.; Mohideen Batcha, M. F.

2017-09-01

Fluidized bed drying are very well known to yield high heat and mass transfer and hence adopted to many industrial drying processes particularly agricultural products. In this paper, recent advances in fluidized bed drying were reviewed and focus is given to the drying related to the usage of Computational Fluid Dynamics (CFD). It can be seen that usage of modern computational tools such as CFD helps to optimize the fluidized bed dryer design and operation for lower energy consumption and thus better thermal efficiency. Among agricultural products that were reviewed in this paper were oil palm frond, wheat grains, olive pomace, coconut, pepper corn and millet.

A mathematical model for DRY-OUT

International Nuclear Information System (INIS)

Mariy, A.; Khattab, M.; Olama, H.

1989-01-01

In this study a model has been developed for describing the thermal surface conditions at dry out in a vertical channel with uniform heat flux. The use of droplet generation rate and vapor-droplet-wall heat transfer relations together with the dry and wet side energy equations lead to evaluation of the wall surface temperature and heat transfer distributions before and after dry out. Comparison with the previous theoretical and experimental results are presented. The steady state approach developed showed to be in good agreement with the experimental results

Refuge behaviour from outdoor thermal environmental stress and seasonal differences of thermal sense in tropical urban climate

Science.gov (United States)

Kurazumi, Y.; Ishii, J.; Fukagawa, K.; Kondo, E.; Aruninta, A.

2017-12-01

Thermal sensation affects body temperature regulation. As a starting point for behavioral body temperature regulation taken to improve from a poor thermal environment to a more pleasant environment, thermal sense of thermal environment stimulus is important. The poupose of this sutudy is to use the outdoor thermal environment evaluation index ETFe to quantify effects on thermal sensations of the human body of a tropical region climate with small annual temperature differences, and to examine seasonal differences in thermal sensation. It was found temperature preferences were lower in the winter season than in the dry season, and that a tolerance for higher temperatures in the dry season than in the winter season. It was found effects of seasonal differences of the thermal environment appear in quantitative changes in thermal sensations. It was found that effects of seasonal differences of the thermal environment do not greatly affect quantitative changes in thermal comfort.

Influence of drying method on the material properties of nanocellulose I: thermostability and crystallinity

Science.gov (United States)

Yucheng Peng; Douglas J. Gardner; Yousoo Han; Alper Kiziltas; Zhiyong Cai; Mandla A. Tshabalala

2013-01-01

The effect of drying method on selected material properties of nanocellulose was investigated. Samples of nanofibrillated cellulose (NFC) and cellulose nanocrystals (CNC) were each subjected to four separate drying methods: air-drying, freeze-drying, spray-drying, and supercritical-drying. The thermal stability and crystallinity of the dried nanocellulose were...

DECIPHERING THERMAL PHASE CURVES OF DRY, TIDALLY LOCKED TERRESTRIAL PLANETS

Energy Technology Data Exchange (ETDEWEB)

Koll, Daniel D. B.; Abbot, Dorian S., E-mail: dkoll@uchicago.edu [Department of the Geophysical Sciences, University of Chicago, Chicago, IL 60637 (United States)

2015-03-20

Next-generation space telescopes will allow us to characterize terrestrial exoplanets. To do so effectively it will be crucial to make use of all available data. We investigate which atmospheric properties can, and cannot, be inferred from the broadband thermal phase curve of a dry and tidally locked terrestrial planet. First, we use dimensional analysis to show that phase curves are controlled by six nondimensional parameters. Second, we use an idealized general circulation model to explore the relative sensitivity of phase curves to these parameters. We find that the feature of phase curves most sensitive to atmospheric parameters is the peak-to-trough amplitude. Moreover, except for hot and rapidly rotating planets, the phase amplitude is primarily sensitive to only two nondimensional parameters: (1) the ratio of dynamical to radiative timescales and (2) the longwave optical depth at the surface. As an application of this technique, we show how phase curve measurements can be combined with transit or emission spectroscopy to yield a new constraint for the surface pressure and atmospheric mass of terrestrial planets. We estimate that a single broadband phase curve, measured over half an orbit with the James Webb Space Telescope, could meaningfully constrain the atmospheric mass of a nearby super-Earth. Such constraints will be important for studying the atmospheric evolution of terrestrial exoplanets as well as characterizing the surface conditions on potentially habitable planets.

Effect of steam thermal treatment on the drying process of Eucalyptus dunnii variables

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Elias Taylor Durgante Severo

2013-12-01

Full Text Available The aim of this study was to evaluate the effect of steam treatment prior to drying on the initial moisture content, moisture gradient, and drying rate in Eucalyptus dunnii Maiden wood. Boards were steamed at 100ºC for 3 h after 1 h of heating-up. Part of these boards was dried in a drying electric oven at 50ºC, and part was dried at kiln. The results showed that the steaming prior to drying of wood: (1 significantly reduced by 9.2% the initial moisture content; (2 significantly increased by 6.2% the drying rate; (3 significantly decreased by 15.6 and 14.8% the moisture gradient between the outer layer and the center of boards and between the outer and intermediate layers of boards, respectively. Steamed boards when dried in an oven showed drying rate of 0.007065 whereas in kiln were 0.008200 and 0.034300 from green to 17 and 17 to 12% moisture content, respectively. It was demonstrated that the steaming prior to drying can be suitable for reduces the drying times of this kind of wood.

Avaliação do consumo crônico de leite e kefir sobre os níveis pressóricos, parâmetros bioquímicos e renais de ratos SHR (Spontaneously Hypertensive Rats) induzidos à síndrome metabólica

OpenAIRE

Gontijo, Luciana Nogueira

2014-01-01

Objetivo: Avaliar a influência do consumo crônico de leite e kefir sobre os níveis pressóricos, parâmetros bioquímicos e renais de ratos machos SHR induzidos à SM. Metodologia: Inoculou-se 5 g de grãos de kefir em 100 mL de leite de vaca pasteurizado com diferentes teores de lipídeos (5,5 % e 3,5 %), a 4 oC. As amostras foram incubadas em estufa a temperatura controlada de 25 + 2 oC, por 24 horas. Nessas amostras foram determinadas a umidade, o teor de cinzas, proteínas, carboidratos, lipídeo...

[Thermal energy utilization analysis and energy conservation measures of fluidized bed dryer].

Science.gov (United States)

Xing, Liming; Zhao, Zhengsheng

2012-07-01

To propose measures for enhancing thermal energy utilization by analyzing drying process and operation principle of fluidized bed dryers,in order to guide optimization and upgrade of fluidized bed drying equipment. Through a systematic analysis on drying process and operation principle of fluidized beds,the energy conservation law was adopted to calculate thermal energy of dryers. The thermal energy of fluidized bed dryers is mainly used to make up for thermal consumption of water evaporation (Qw), hot air from outlet equipment (Qe), thermal consumption for heating and drying wet materials (Qm) and heat dissipation to surroundings through hot air pipelines and cyclone separators. Effective measures and major approaches to enhance thermal energy utilization of fluidized bed dryers were to reduce exhaust gas out by the loss of heat Qe, recycle dryer export air quantity of heat, preserve heat for dry towers, hot air pipes and cyclone separators, dehumidify clean air in inlets and reasonably control drying time and air temperature. Such technical parameters such air supply rate, air inlet temperature and humidity, material temperature and outlet temperature and humidity are set and controlled to effectively save energy during the drying process and reduce the production cost.

Effect of different drying techniques on the volatile compounds ...

African Journals Online (AJOL)

Purpose: To examine the volatile compounds, thermal stability and morphological characteristics of stevia (Stevia rebaudiana Bertoni) leaves after sun, oven and microwave drying. Methods: Gas chromatography-mass spectrometry with a spectral analysis manager was used to separate the volatile compounds. Dried stevia ...

Thermal insulation

International Nuclear Information System (INIS)

Pinsky, G.P.

1977-01-01

Thermal insulation for vessels and piping within the reactor containment area of nuclear power plants is disclosed. The thermal insulation of this invention can be readily removed and replaced from the vessels and piping for inservice inspection, can withstand repeated wettings and dryings, and can resist high temperatures for long periods of time. 4 claims, 3 figures

Symbiosis between microorganisms from kombucha and kefir: Potential significance to the enhancement of kombucha function.

Science.gov (United States)

Yang, Zhiwei; Zhou, Feng; Ji, Baoping; Li, Bo; Luo, Yangchao; Yang, Li; Li, Tao

2010-01-01

Gluconacetobacter sp. A4 (G. sp. A4), which had strong ability to produce d-saccharic acid 1, 4 lactone (DSL), was the key functional bacteria isolated from the kombucha preserved. This paper investigated the interaction between G. sp. A4 and ten different strains of lactic acid bacteria (LAB) obtained from kefir. The result suggested that the LAB promoted DSL production of G. sp. A4 to different extents, ranging from 4.86% to 86.70%. Symbiosis between G. sp. A4 and LAB was studied. LAB's metabolites, xylitol, and acetic acid, were utilized by G. sp. A4, and it promoted the growth of G. sp. A4 and yield of DSL. Therefore, in developing starter cultures for kombucha fermentation process, a mixed flora of LAB and G. sp. A4 would be the optimal combination.

Thermal comfort requirements in hot dry regions with special reference to Riyadh Part 2: for Friday prayer

Energy Technology Data Exchange (ETDEWEB)

Saeed, S.A.R. [King Saud University, Riyadh (Saudi Arabia). Dept. of Architecture and Building Science

1996-01-01

This study is an attempt to define thermal comfort requirements for Friday prayer during the hot season of Riyadh, Saudi Arabia. According to Islam, a Muslim should perform his prayers five times a day. The obligatory five prayers are Subuh prayer immediately before dawn, Thohor prayer in the afternoon, Assor prayer in late afternoon, Maghreb prayer immediately after sunset, and Ishaa prayer early evening. Generally, Muslims are encouraged to perform all five prayers in a mosque. Friday prayer that replaces Thohor prayer once a week, should take place in one of the main mosques of the neighbourhood. The mosque where Friday prayer could be performed is known as Friday mosque. Usually Friday prayer is attended by hundreds of worshippers and takes place in the afternoon. Since the summer of Riyadh is characterised by a very high temperature and a very low relative humidity, the indoor climate of the Friday mosque (Al-Masjed Al-Gamae) need a special study. This is the second part of a series of field investigations dealing with thermal comfort requirements in the hot-dry region of Saudi Arabia. (author)

Heat transfer modelling in a spent-fuel dry storage system

International Nuclear Information System (INIS)

Ritz, J.B.; Le Bonhomme, S.

2001-01-01

The purpose of this paper is to present a numerical modelling of heat transfers in a Spent-Fuel horizontal dry storage. The horizontal dry storage is an interesting issue to momentary store spent fuel containers before the final storage. From a thermal point of view, the cooling of spent fuel container by natural convection is a suitable and inexpensive process but it necessitates to well define the dimensions of the concept due to the difficulty to control the thermal environment. (author)

EXPERIMENTAL STUDY OF THERMAL EFFECT OF DRYING, HEATING, BLOWING MACHINE WITH DIFFERENT STAGE

OpenAIRE

Aditya Pratap Singh; Disha Dinesh Sahni; Arpit Dubey

2016-01-01

Drying is the oldest method of preserving food. The early American settlers dried foods such as corn, apple slices, currants, grapes, and meat. Compared with other methods, drying is quite simple. In fact, you may already have most of the equipment on hand. Dried foods keep well because the moisture content is so low that spoilage organisms cannot grow. Drying will never replace canning and freezing because these methods do a better job of retaining the taste, appearance, and nutritive va...

Kefir and champagne vinegar to defeat bacterial vaginosis in woman, avoiding oral metronidazole, clindamycin and bothersome douchings

Directory of Open Access Journals (Sweden)

Piotr Brzezinski

2018-02-01

Full Text Available Scope ouf our study is to treat with natural remedies vaginitis in woman, when it has been detected the disease originates from bacterical assault (Gardnerella vaginalis and/or Streptococca spp. in order to avoid the administration of perilous antibiotics and elicit sexual desire and eliminate pain during urination in the woman who has suffered from this disease after 4-5 days only. We have to proceed with the preliminary phase of a simplest test (the ammin whiff test and determine the type of vaginitis and thus treat it using champagne or cider vinegar to adjust mucosal pH and kefir, a fermented beverage, that is extremely rich in mesophyllic bacteria, apt to reveal an important and suggestive function regard vaginal microbes.

Non-thermal plasma treatment as a new biotechnology in relation to seeds, dry fruits, and grains

Science.gov (United States)

Božena, ŠERÁ; Michal, ŠERÝ

2018-04-01

Non-thermal plasma (NTP) technology offers wide potential use in the food technology, the same as in the unconventional agriculture. Some seeds, dry fruits, grains and their sprouts gain popularity in the culinary industry as ‘raw seeds’. This review paper draws the current research and trends in NTP pre-treatment of selected seeds/fruits that are useable as ‘raw seeds’. The main applications are connected with activation of seed germination, early growth of seedlings, microbial inactivation of seed/fruit surface, and possibility of increasing quantity of biological active compounds in sprouting seeds. The paper presents a list of plant species that are able to be used as ‘raw seed’ including current information about main type of NTP treatment implemented.

Effects of annealing on the physical properties of therapeutic proteins during freeze drying process.

Science.gov (United States)

Lim, Jun Yeul; Lim, Dae Gon; Kim, Ki Hyun; Park, Sang-Koo; Jeong, Seong Hoon

2018-02-01

Effects of annealing steps during the freeze drying process on etanercept, model protein, were evaluated using various analytical methods. The annealing was introduced in three different ways depending on time and temperature. Residual water contents of dried cakes varied from 2.91% to 6.39% and decreased when the annealing step was adopted, suggesting that they are directly affected by the freeze drying methods Moreover, the samples were more homogenous when annealing was adopted. Transition temperatures of the excipients (sucrose, mannitol, and glycine) were dependent on the freeze drying steps. Size exclusion chromatography showed that monomer contents were high when annealing was adopted and also they decreased less after thermal storage at 60°C. Dynamic light scattering results exhibited that annealing can be helpful in inhibiting aggregation and that thermal storage of freeze-dried samples preferably induced fragmentation over aggregation. Shift of circular dichroism spectrum and of the contents of etanercept secondary structure was observed with different freeze drying steps and thermal storage conditions. All analytical results suggest that the physicochemical properties of etanercept formulation can differ in response to different freeze drying steps and that annealing is beneficial for maintaining stability of protein and reducing the time of freeze drying process. Copyright © 2017 Elsevier B.V. All rights reserved.

DESIGN AND THERMAL PERFORMANCE OF THE SOLAR BIOMASS HYBRID DRYER FOR CASHEW DRYING

Directory of Open Access Journals (Sweden)

Saravanan Dhanuskodi

2014-12-01

Full Text Available Drying of Cashew nut to remove testa is one of the most energy-intensive processes of cashew nut process industry. For this reason a hybrid dryer consisting of a solar flat plate collector, a biomass heater and a drying chamber is designed and fabricated. 40 kg of Cashew nut with initial moisture of 9 % is used in the experiment. The performance test of the dryer is carried out in two modes of operation: hybrid-forced convection and hybrid-natural convection. Drying time and drying efficiency during these two modes of operation are estimated and compared with the sun drying. The system is capable of attaining drying temperature between 50º and 70ºC. In the hybrid forced drying, the required moisture content of 3% is achieved within 7 hours and the average system efficiency is estimated as 5.08%. In the hybrid natural drying, the required moisture content is obtained in 9 hours and the average system efficiency is 3.17%. The fuel consumption during the drying process is 0.5 kg/hr and 0.75 kg/hr for forced mode and natural mode, respectively. The drying process in the hybrid forced mode of operation is twice faster than the sun drying. The dryer can be operated in any climatic conditions: as a solar dryer on normal sunny days, as a biomass dryer at night time and as a hybrid dryer on cloudy days. Based on the experimental study, it is concluded that the developed hybrid dryer is suitable for small scale cashew nut farmers in rural areas of developing countries.

Characterization of Wet and Dry Deposition in the Downwind of Industrial Sources in a Dry Tropical Area

Directory of Open Access Journals (Sweden)

Raj K. Singh

2001-01-01

Full Text Available An atmospheric deposition study was conducted in the downwind of Shaktinagar Thermal Power Plant (STPP, Renusagar Thermal Power Plant (RTPP, and Anpara Thermal Power Plant (ATPP, at Singrauli region, Uttar Pradesh (UP, India to characterize dry and wet deposition in relation to different pollution loading. During the study period, dry and wet depositions and levels of gaseous pollutants (SO2 and NO2 were estimated across the sites. Dry deposition was collected on a monthly basis and wet deposition on an event basis. Depositions were analyzed for pH, nitrate (NO3�, ammonium (NH4+, and sulphate (SO42� contents. Dry deposition rate both collected as clearfall and throughfall varied between 0.15 to 2.28 and 0.33 to 3.48 g m�2 day�1, respectively, at control and maximally polluted sites. The pH of dry deposition varied from 5.81 to 6.89 during winter and 6.09 to 7.02 during summer across the sites. During the rainy season, the mean pH of clear wet deposition varied from 6.56 to 7.04 and throughfall varied from 6.81 to 7.22. The concentrations of NO2 and SO2 pollutants were highest during the winter season. Mean SO2 concentrations varied from 18 to 75 �g m�3 at control and differently polluted sites during the winter season. The variation in NO2 concentrations did not show a pattern similar to that of SO2. The highest NO2 concentration during the winter season was 50 �g m�3, observed near RTPP. NO2 concentration did not show much variation among different sites, suggesting that the sources of NO2 emission are evenly distributed along the sites. The concentrations of NH4+, NO3�, and SO42� ions in dry deposition were found to be higher in summer as compared to the winter season. In dry deposition (clearfall the concentrations of NH4+, NO3�, and SO42� varied from 0.13 to 1.0, 0.81 to 1.95, and 0.82 to 3.27 mg l�1, respectively, during winter. In wet deposition (clearfall, the above varied from 0.14 to 0.74, 0.81 to 1.82, and 0

Characterization of wet and dry deposition in the downwind of industrial sources in a dry tropical area.

Science.gov (United States)

Singh, R K; Agrawal, M

2001-12-19

An atmospheric deposition study was conducted in the downwind of Shaktinagar Thermal Power Plant (STPP), Renusagar Thermal Power Plant (RTPP), and Anpara Thermal Power Plant (ATPP), at Singrauli region, Uttar Pradesh (UP), India to characterize dry and wet deposition in relation to different pollution loading. During the study period, dry and wet depositions and levels of gaseous pollutants (SO2 and NO2) were estimated across the sites. Dry deposition was collected on a monthly basis and wet deposition on an event basis. Depositions were analyzed for pH, nitrate (NO3-), ammonium (NH4+), and sulphate (SO4(2-)) contents. Dry deposition rate both collected as clearfall and throughfall varied between 0.15 to 2.28 and 0.33 to 3.48 g m(-2) day(-1), respectively, at control and maximally polluted sites. The pH of dry deposition varied from 5.81 to 6.89 during winter and 6.09 to 7.02 during summer across the sites. During the rainy season, the mean pH of clear wet deposition varied from 6.56 to 7.04 and throughfall varied from 6.81 to 7.22. The concentrations of NO2 and SO2 pollutants were highest during the winter season. Mean SO2 concentrations varied from 18 to 75 g m(-3) at control and differently polluted sites during the winter season. The variation in NO2 concentrations did not show a pattern similar to that of SO2. The highest NO2 concentration during the winter season was 50 g m(-3), observed near RTPP. NO2 concentration did not show much variation among different sites, suggesting that the sources of NO2 emission are evenly distributed along the sites. The concentrations of NH4+, NO3-, and SO4(2-) ions in dry deposition were found to be higher in summer as compared to the winter season. In dry deposition (clearfall) the concentrations of NH4+, NO3-, and SO4(2-) varied from 0.13 to 1.0, 0.81 to 1.95, and 0.82 to 3.27 mg l(-1), respectively, during winter. In wet deposition (clearfall), the above varied from 0.14 to 0.74, 0.81 to 1.82, and 0.67 to 2.70 mg l(-1

Oxidation kinetics of Si and SiGe by dry rapid thermal oxidation, in-situ steam generation oxidation and dry furnace oxidation

Science.gov (United States)

Rozé, Fabien; Gourhant, Olivier; Blanquet, Elisabeth; Bertin, François; Juhel, Marc; Abbate, Francesco; Pribat, Clément; Duru, Romain

2017-06-01

The fabrication of ultrathin compressively strained SiGe-On-Insulator layers by the condensation technique is likely a key milestone towards low-power and high performances FD-SOI logic devices. However, the SiGe condensation technique still requires challenges to be solved for an optimized use in an industrial environment. SiGe oxidation kinetics, upon which the condensation technique is founded, has still not reached a consensus in spite of various studies which gave insights into the matter. This paper aims to bridge the gaps between these studies by covering various oxidation processes relevant to today's technological needs with a new and quantitative analysis methodology. We thus address oxidation kinetics of SiGe with three Ge concentrations (0%, 10%, and 30%) by means of dry rapid thermal oxidation, in-situ steam generation oxidation, and dry furnace oxidation. Oxide thicknesses in the 50 Å to 150 Å range grown with oxidation temperatures between 850 and 1100 °C were targeted. The present work shows first that for all investigated processes, oxidation follows a parabolic regime even for thin oxides, which indicates a diffusion-limited oxidation regime. We also observe that, for all investigated processes, the SiGe oxidation rate is systematically higher than that of Si. The amplitude of the variation of oxidation kinetics of SiGe with respect to Si is found to be strongly dependent on the process type. Second, a new quantitative analysis methodology of oxidation kinetics is introduced. This methodology allows us to highlight the dependence of oxidation kinetics on the Ge concentration at the oxidation interface, which is modulated by the pile-up mechanism. Our results show that the oxidation rate increases with the Ge concentration at the oxidation interface.

Lactobacillus plantarum CIDCA 8327: An α-glucan producing-strain isolated from kefir grains.

Science.gov (United States)

Gangoiti, M V; Puertas, A I; Hamet, M F; Peruzzo, P J; Llamas, M G; Medrano, M; Prieto, A; Dueñas, M T; Abraham, A G

2017-08-15

Lactobacillus plantarum CIDCA 8327 is an exopolysaccharide (EPS)-producer strain isolated from kefir with promising properties for the development of functional foods. The aim of the present study was to characterize the structure of the EPS synthesized by this strain grown in skim milk or semidefined medium (SDM). Additionally, genes involved in EPS synthesis were detected by PCR. L. plantarum produces an EPS with a molecular weight of 10 4 Da in both media. When grown in SDM produce an heteropolysaccharide composed mainly of glucose, glucosamine and rhamnose meanwhile the EPS produced in milk was composed exclusively of glucose indicating the influence of the sugar source. FTIR spectra of this EPS showed signals attributable to an α-glucan. Both by 1 H NMR and methylation analysis it was possible to determine that this polysaccharide is a branched α-(1→4)-d-glucan composed of 80% linear α-(1→4)-d-glucopyranosyl units and 19% (1→4)-d-glucopyranosyl units substituted at O-3 by single α-d-glucopyranosil residues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Steam atmosphere drying concepts using steam exhaust recompression

Energy Technology Data Exchange (ETDEWEB)

DiBella, F.A. (TECOGEN, Inc., Waltham, MA (United States))

1992-08-01

In the US industrial drying accounts for approximately 1.5 quads of energy use per year. Annual industrial dryer expenditures are estimated to be in the $500 million range. Industrial drying is a significant energy and monetary expense. For the thermal drying processes in which water is removed via evaporation from the feedstock, attempts have been made to reduce the consumption of energy using exhaust waste heat recovery techniques, improved dryer designs, or even the deployment of advanced mechanical dewatering techniques. Despite these efforts, it is obvious that a large amount of thermal energy is often still lost if the latent heat of evaporation from the evaporated water cannot be recovered and/or in some way be utilized as direct heat input into the dryer. Tecogen Inc. is conducting research and development on an industrial drying concept. That utilizes a directly or indirectly superheated steam cycle atmosphere with exhaust steam recompression to recover the latent heat in the exhaust that would otherwise be lost. This approach has the potential to save 55 percent of the energy required by a conventional air dryer. Other advantages to the industrial dryer user include: A 35-percent reduction in the yearly cost per kg[sub evap] to dry wet feedstock, Reduced airborne emissions, Reduced dry dust fire/explosion risks, Hot product not exposed to oxygen thus, the product quality is enhanced, Constant rate drying in steam atmosphere, Reduced dryer size and cost, Reduced dryer heat losses due to lower dryer inlet temperatures. Tecogen has projected that the steam atmosphere drying system is most suitable as a replacement technology for state-of-the-art spray, flash, and fluidized bed drying systems. Such systems are utilized in the food and kindred products; rubber products; chemical and allied products; stone, clay, and glass; textiles; and pulp and paper industrial sectors.

Steam atmosphere drying concepts using steam exhaust recompression

Energy Technology Data Exchange (ETDEWEB)

DiBella, F.A. [TECOGEN, Inc., Waltham, MA (United States)

1992-08-01

In the US industrial drying accounts for approximately 1.5 quads of energy use per year. Annual industrial dryer expenditures are estimated to be in the $500 million range. Industrial drying is a significant energy and monetary expense. For the thermal drying processes in which water is removed via evaporation from the feedstock, attempts have been made to reduce the consumption of energy using exhaust waste heat recovery techniques, improved dryer designs, or even the deployment of advanced mechanical dewatering techniques. Despite these efforts, it is obvious that a large amount of thermal energy is often still lost if the latent heat of evaporation from the evaporated water cannot be recovered and/or in some way be utilized as direct heat input into the dryer. Tecogen Inc. is conducting research and development on an industrial drying concept. That utilizes a directly or indirectly superheated steam cycle atmosphere with exhaust steam recompression to recover the latent heat in the exhaust that would otherwise be lost. This approach has the potential to save 55 percent of the energy required by a conventional air dryer. Other advantages to the industrial dryer user include: A 35-percent reduction in the yearly cost per kg{sub evap} to dry wet feedstock, Reduced airborne emissions, Reduced dry dust fire/explosion risks, Hot product not exposed to oxygen thus, the product quality is enhanced, Constant rate drying in steam atmosphere, Reduced dryer size and cost, Reduced dryer heat losses due to lower dryer inlet temperatures. Tecogen has projected that the steam atmosphere drying system is most suitable as a replacement technology for state-of-the-art spray, flash, and fluidized bed drying systems. Such systems are utilized in the food and kindred products; rubber products; chemical and allied products; stone, clay, and glass; textiles; and pulp and paper industrial sectors.

Analysis of metabolic activity of lactic acid bacteria and yeast in model kefirs made from goat’s milk and mixtures of goat’s milk with mare’s milk based on changes in electrical conductivity and impedance

Directory of Open Access Journals (Sweden)

Dorota Cais-Sokolińska

2017-01-01

Full Text Available The aim of this study was to analyse the metabolic activity of lactic acid bacteria and yeast based of changes in electrical conductivity and electrical impedance during fermentation of goat milk and mixtures of goat’s milk and mare’s milk (1:1, 1:2. As a result of fermentation, conductivity increased 1.4-fold. The conductivity of kefir prepared from goat and mare milk mixed at a ratio of 1:2 (6.210 Ω-3∙cm-1 was lower than that of the 1:1 mixture or of goat milk alone (7.242 Ω-3∙cm-1. A significant dependence of electrical conductivity and pH (0.970 ≤ r ≤ 0.993 was recorded during fermentation. The addition of mare milk to goat milk significantly slowed down the growth of LAB (Δλ = 0.8 h and yeasts during kefir production.

Thermophysiological Properties of Dry and Wet Functional Sportswear Made of Synthetic Fibres

Directory of Open Access Journals (Sweden)

Monika Bogusławska – Bączek

2017-12-01

Full Text Available In recent times, knitted fabrics made from synthetic fibres are being used increasingly for sportswear. This type of clothing should ensure thermal comfort in all weather conditions, regardless of the activity of the wearer. The most important thermal properties include thermal conductivity and resistance, as well as water vapour permeability. Sportswear often becomes wet (from sweat or due to a humid environment, which can have a signifi cant effect on thermal properties, while most testing methods only perform measurements in a dry state. This paper therefore presents our study of the thermal properties of different types of knitted fabrics in both dry and wet states. The presented research proved that wet knitwear results in a signifi cant loss of thermal comfort. This phenomenon is exacerbated when the moisture content of a material increases, and depends on the structure and filling of tested materials.

PULSE DRYING EXPERIMENT AND BURNER CONSTRUCTION

Energy Technology Data Exchange (ETDEWEB)

Robert States

2006-07-15

Non steady impingement heat transfer is measured. Impingement heating consumes 130 T-BTU/Yr in paper drying, but is only 25% thermally efficient. Pulse impingement is experimentally shown to enhance heat transfer by 2.8, and may deliver thermal efficiencies near 85%. Experimental results uncovered heat transfer deviations from steady theory and from previous investigators, indicating the need for further study and a better theoretical framework. The pulse burner is described, and its roll in pulse impingement is analyzed.

Accelerated storage testing of freeze-dried Pseudomonas ...

African Journals Online (AJOL)

Accelerated storage testing of freeze-dried Pseudomonas fluorescens BTP1, ... of all P. fluorescens strains were not significantly different and thermal inactivation ... useful to the development of improved reference materials and samples held ...

Charging-discharging characteristics of macro-encapsulated phase change materials in an active thermal energy storage system for a solar drying kiln

Directory of Open Access Journals (Sweden)

Kumar Shailendra

2017-01-01

Full Text Available The present study explores suitability of two phase change materials (PCM for development of an active thermal storage system for a solar drying kiln by studying their melting and solidification behaviors. A double glass glazing prototype solar kiln was used in the study. The storage system consisted of a water storage tank with PCM placed inside the water in high density polyethylene containers. The water in the tank was heated with help of solar energy using an evacuated tube collector array. The melting and solidification temperature curves of PCM were obtained by charging and discharging the water tank. The study illustrated the utility of the PCM in using the stored thermal energy during their discharge to enhance the temperature inside the kiln. The rate of temperature reduction was found to be higher for paraffin wax as compared to a fatty acid based PCM. The water temperature during the discharge of the PCM showed dependence on the discharge characteristics of each PCM suggesting their suitability in designing active thermal storage systems.

The Effect of Passive Design Strategies on Thermal Performance of Female Secondary School Buildings during Warm Season in Hot Dry Climate

Directory of Open Access Journals (Sweden)

Sahar eZahiri

2016-03-01

Full Text Available This paper describes a series of field studies and simulation analysis to improve the thermal performance of school buildings in the city of Tehran in Iran during warm season. The field studies used on-site measurement and questionnaire-based survey in the warm spring season in a typical female secondary school building. The on-site monitoring assessed the indoor air temperature and humidity levels of six classrooms while the occupants completed questionnaires covering their thermal sensations and thermal preferences. Moreover, thermal simulation analysis was also carried out to evaluate and improve the thermal performance of the classrooms based on the students’ thermal requirements and passive design strategies. In this study, the environmental design guidelines for female secondary school buildings were introduced for the hot and dry climate of Tehran, using passive design strategies. The study shows that the application of passive design strategies including south and south-east orientation, 10cm thermal insulation in wall and 5cm in the roof, and the combination of 30cm side fins and overhangs as a solar shading devices, as well as all-day ventilation strategy and the use of thermal mass materials with 25cm-30cm thickness, has considerable impact on indoor air temperatures in warm season in Tehran and keeps the indoor environment in an acceptable thermal condition. The results of the field studies also indicated that most of the occupants found their thermal environment not to be comfortable and the simulation results showed that passive design techniques had a significant influence on the indoor air temperature and can keep it in an acceptable range based on the female students’ thermal requirement. Therefore, in order to enhance the indoor environment and to increase the learning performance of the students, it is necessary to use the appropriate passive design strategies, which also reduce the need for mechanical systems and

Thermal/moisture-related stresses and fracture behaviour in solid wood members during forced drying

DEFF Research Database (Denmark)

Larsen, Finn

, in particular the stress and cracking that takeplace during kiln-drying. Both experimental and numerical work was carried out so as to obtain knowledge regarding stress, strain, mechano-sorption and crackbehaviours in wood during drying.The investigations aimed also at revealing how drying damagecan best...... of wood without injury to the timber itself. When solid wood products are dried from a green condition down to an average moisture content level close to the service life conditions of the final product, significant moisture-induced stresses and related fracturing can occur. The drying stresses arise...... with a drying history that was generated, to verify a model that was used to simulate disc samples of the same type. The stresses were analyzed so as to clarify whether and when critical stress stateswere encountered during the drying process. The reversibility of the mechano-sorptive strains, i...

Effect of drying temperatures on starch-related functional and thermal properties of acorn flours.

Science.gov (United States)

Correia, P R; Beirão-da-Costa, M L

2011-03-01

The application of starchy flours from different origins in food systems depends greatly on information about the chemical and functional properties of such food materials. Acorns are important forestry resources in the central and southern regions of Portugal. To preserve these fruits and to optimize their use, techniques like drying are needed. The effects of different drying temperatures on starch-related functional properties of acorn flours obtained from dried fruits of Quercus rotundifolia (QR) and Quercus suber (QS) were evaluated. Flours were characterized for amylose and resistant starch (RS) contents, swelling ability, and gelatinization properties. Drying temperature mainly affected amylose content and viscoamylographic properties. Amylograms of flours from fruits dried at 60 °C displayed higher consistency (2102 B.U. and 1560 B.U., respectively, for QR and QS). The transition temperatures and enthalpy were less affected by drying temperature, suggesting few modifications in starch structure during drying. QR flours presented different functional properties to those obtained from QS acorn flours. The effect of drying temperatures were more evident in QR.

Geochemistry of thermal/mineral waters in the Clear Lake region, California, and implications for hot dry rock geothermal development

Energy Technology Data Exchange (ETDEWEB)

Goff, F.; Adams, A.I.; Trujillo, P.E.; Counce, D.; Mansfield, J.

1993-02-01

Thermal/mineral waters of the Clear Lake region are broadly classified as thermal meteoric and connote types based on chemical and isotopic criteria. Ratios of conservative components such as B/Cl are extremely different among all thermal/mineral waters of the Clear Lake region except for clusters of waters emerging from specific areas such as the Wilbur Springs district and the Agricultural Park area south of Mt. Konocti. In contrast, ratios of conservative components in large, homogeneous geothermal reservoirs are constant. Stable isotope values of Clear Lake region waters show a mixing trend between thermal meteoric and connote end-members. The latter end-member has enriched [delta]D as well as enriched d[sup l8]O, very different from typical high-temperature geothermal reservoir waters. Tritium data and modeling of ages indicate most Clear Lake region waters are 500 to > 10,000 yr., although mixing of old and young components is implied by the data. The age of end-member connate water is probably > 10,000 yr. Subsurface equilibration temperature of most thermal/mineral waters of the Clear Lake region is [le] 150[degrees]C based on chemical geothermometers but it is recognized that Clear Lake region waters are not typical geothermal fluids and that they violate rules of application of many geothermometers. The combined data indicate that no large geothermal reservoir underlies the Clear Lake region and that small localized reservoirs have equilibration temperatures [le] 150[degrees]C (except for Sulphur Bank Mine). Hot dry rock technologies are the best way to commercially exploit the known high temperatures existing beneath the Clear Lake region, particularly within the main Clear Lake volcanic field.

Rehydration kinetics of freeze-dried carrots

NARCIS (Netherlands)

Vergeldt, F.J.; Dalen, van G.; Duijster, A.J.; Voda, A.; Khalloufi, S.; Vliet, van L.J.; As, van H.; Duynhoven, van J.P.M.; Sman, van der R.G.M.

2014-01-01

Rehydration kinetics by two modes of imbibition is studied in pieces of freeze-dried winter carrot, after different thermal pre-treatments. Water ingress at room temperature is measured in real time by in situ MRI and NMR relaxometry. Blanched samples rehydrate substantially faster compared to

Standard guide for drying behavior of spent nuclear fuel

CERN Document Server

American Society for Testing and Materials. Philadelphia

2008-01-01

1.1 This guide is organized to discuss the three major components of significance in the drying behavior of spent nuclear fuel: evaluating the need for drying, drying spent nuclear fuel, and confirmation of adequate dryness. 1.1.1 The guide addresses drying methods and their limitations in drying spent nuclear fuels that have been in storage at water pools. The guide discusses sources and forms of water that remain in SNF, its container, or both, after the drying process and discusses the importance and potential effects they may have on fuel integrity, and container materials. The effects of residual water are discussed mechanistically as a function of the container thermal and radiological environment to provide guidance on situations that may require extraordinary drying methods, specialized handling, or other treatments. 1.1.2 The basic issue in drying is to determine how dry the SNF must be in order to prevent issues with fuel retrievability, container pressurization, or container corrosion. Adequate d...

Spray drying egg using either maltodextrin or nopal mucilage as stabilizer agents.

Science.gov (United States)

Medina-Torres, L; Calderas, F; Nuñez Ramírez, D M; Herrera-Valencia, E E; Bernad Bernad, M J; Manero, O

2017-12-01

In this work, a comparative study between spray drying (SD) of fresh egg by either maltodextrin (MD) or nopal-mucilage (MN) as stabilizing vectors was made. The powders obtained were characterized for drying performance, moisture content, chemical proximate analysis, thermal analysis (TGA), chemical composition (FTIR), microscopy (SEM) and rheology (viscoelasticity and steady state simple shear viscosity). Infrared analysis showed that MN has the effect of a thickening agent rather than an encapsulating one. Results indicated that SD egg with MN produced a high thermal and mechanical stable product and rendered the highest drying performance, producing a more uniform and defined sphere-shaped morphology in comparison to egg SD either alone and with MD.

Effects of the oral administration of the products derived from milk fermentation by kefir microflora on immune stimulation.

Science.gov (United States)

Vinderola, Gabriel; Perdigón, Gabriela; Duarte, Jairo; Farnworth, Edward; Matar, Chantal

2006-11-01

Nutritional status has a major impact on the immune system. Probiotic effects ascribed to fermented dairy products arise not only from whole microorganisms but also from metabolites (peptides, exopolysaccharides) produced during the fermentation. We recently demonstrated the immunomodulating capacity of kefir in a murine model. We now aimed at studying the immunomodulating capacity in vivo of the products derived from milk fermentation by kefir microflora (PMFKM) on the gut. BALB/c mice received the PMFKM for 2, 5 or 7 consecutive days. IgA+ and IgG+ cells were determined on histological slices of the small and large intestine. IL-4, IL-6, IL-10, IL-12, IFNgamma and TNFalpha were determined in the gut, intestinal fluid and blood serum. IL-6 was also determined in the supernatant of a primary culture of small intestine epithelial cells challenged with PMFKM. PMFKM up-regulated IL-6 secretion, necessary for B-cell terminal differentiation to IgA secreting cells in the gut lamina propria. There was an increase in the number of IgA+ cells in the small and large intestine. The increase in the number of IgA+ cells was accompanied by an increase in the number of IL-4+, IL-10+ and IL-6+ cells in the small intestine. Effects of PMFKM in the large intestine were less widely apparent than the ones observed at the small intestine lamina propria. All cytokines that increased in the small intestine lamina propria, also did so in blood serum, reflecting here the immunostimulation achieved in the gut mucosa. We observed that the PMFKM induced a mucosal response and it was able to up and down regulate it for protective immunity, maintaining the intestinal homeostasis, enhancing the IgA production at both the small and large intestine level. The opportunity exists then to manipulate the constituents of the lumen of the intestine through dietary means, thereby enhancing the health status of the host.

Studies and research concerning BNFP: spent fuel dry storage studies at the Barnwell Nuclear Fuel Plant

International Nuclear Information System (INIS)

Anderson, K.J.

1980-09-01

Conceptual designs are presented utilizing the Barnwell Nuclear Fuel Plant for the dry interim storage of spent light water reactor fuel. Studies were conducted to determine feasible approaches to storing spent fuel by methods other than wet pool storage. Fuel that has had an opportunity to cool for several years, or more, after discharge from a reactor is especially adaptable to dry storage since its thermal load is greatly reduced compared to the thermal load immediately following discharge. A thermal analysis was performed to help in determining the feasibility of various spent fuel dry storage concepts. Methods to reject the heat from dry storage are briefly discussed, which include both active and passive cooling systems. The storage modes reviewed include above and below ground caisson-type storage facilities and numerous variations of vault, or hot cell-type, storage facilities

Thermal separation of soil particles from thermal conductivity measurement under various air pressures.

Science.gov (United States)

Lu, Sen; Ren, Tusheng; Lu, Yili; Meng, Ping; Zhang, Jinsong

2017-01-05

The thermal conductivity of dry soils is related closely to air pressure and the contact areas between solid particles. In this study, the thermal conductivity of two-phase soil systems was determined under reduced and increased air pressures. The thermal separation of soil particles, i.e., the characteristic dimension of the pore space (d), was then estimated based on the relationship between soil thermal conductivity and air pressure. Results showed that under both reduced and increased air pressures, d estimations were significantly larger than the geometrical mean separation of solid particles (D), which suggested that conductive heat transfer through solid particles dominated heat transfer in dry soils. The increased air pressure approach gave d values lower than that of the reduced air pressure method. With increasing air pressure, more collisions between gas molecules and solid surface occurred in micro-pores and intra-aggregate pores due to the reduction of mean free path of air molecules. Compared to the reduced air pressure approach, the increased air pressure approach expressed more micro-pore structure attributes in heat transfer. We concluded that measuring thermal conductivity under increased air pressure procedures gave better-quality d values, and improved soil micro-pore structure estimation.

Simultaneous application of microwave energy and hot air to whole drying process of apple slices: drying kinetics, modeling, temperature profile and energy aspect

Science.gov (United States)

Horuz, Erhan; Bozkurt, Hüseyin; Karataş, Haluk; Maskan, Medeni

2018-02-01

Drying kinetics, modeling, temperature profile and energy indices were investigated in apple slices during drying by a specially designed microwave-hot air domestic hybrid oven at the following conditions: 120, 150 and 180 W microwave powers coupled with 50, 60 and 70 °C air temperatures. Both sources of energy were applied simultaneously during the whole drying processes. The drying process continued until the moisture content of apple slices reached to 20% from 86.3% (wet basis, w.b). Drying times ranged from 330 to 800 min and decreased with increasing microwave power and air temperatures. The constant rate period was only observed at low microwave powers and air temperatures. Two falling rate periods were observed. Temperature of apple slices sharply increased within the first 60 min, then reached equilibrium with drying medium and finally increased at the end of the drying process. In order to describe drying behavior of apple slices nine empirical models were applied. The Modified Logistic Model fitted the best our experimental data ( R 2 = 0.9955-0.9998; χ 2 = 3.46 × 10-5-7.85 × 10-4 and RMSE = 0.0052-0.0221). The effective moisture and thermal diffusivities were calculated by Fick's second law and ranged from 1.42 × 10-9 to 3.31 × 10-9 m2/s and 7.70 × 10-9 to 12.54 × 10-9 m2/s, respectively. The activation energy ( Ea) values were calculated from effective moisture diffusivity ( Deff), thermal diffusivity ( α) and the rate constant of the best model ( k). The Ea values found from these three terms were similar and varied from 13.04 to 33.52 kJ/mol. Energy consumption and specific energy requirement of the hybrid drying of apple slices decreased and energy efficiency of the drying system increased with increasing microwave power and air temperature. Apples can be dried rapidly and effectively by use of the hybrid technique.

Practical use of solar heating-dehumidification dry kiln

Energy Technology Data Exchange (ETDEWEB)

Kobayashi, Yoshinori

1988-06-01

In order to decrease the energy cost for drying, a solar-dehumidification dry kiln which used the dehumidification dry process together with the solar thermal drier was developed and tested. In the daytime the drying temperature rose up to 60/sup 0/C in summer and 40/sup 0/C in winter, and it was kept higher by 15 to 20/sup 0/C than the outside temperature at night. Owing to the adoption of the combination of direct solar heating and exhausting highly humid air, it was not necessary to operate the dry kiln in the day time. Average electrical energy consumption which was consumed to 15% moisture content from the raw lumber was about 73kWh/m/sup 3/ in summer which was lowest, about 87kWh/m/sup 3/ in winter. Energy cost required for the solar dehumidification dry kiln is 1/2 to 2/3 of that of the conventional dehumidification dry kiln. The solar-dehumidification dry kiln has a merit of cheaper operating cost in the low energy cost and reduced drying time. (7 figs, 1 tab, 6 refs)

Novel hybridized drying methods for processing of apple fruit: Energy conservation approach

International Nuclear Information System (INIS)

Hazervazifeh, Amin; Nikbakht, Ali M.; Moghaddam, Parviz A.

2016-01-01

Strategic outlook of apple cultivation and its significant post-processing challenges have been the leading factors for energy and time saving research approaches in apple processing. In this research, apple slices were subjected to hot air flow, microwave radiation and combined microwave-hot air flow drying. Drying time, energy consumption and thermal efficiency at different microwave power levels (500 W, 1000 W, 1500 W and 2000 W), hot air temperatures (40 °C, 50 °C, 60 °C and 70 °C) and inlet air velocities (0.5 ms"−"1, 1 ms"−"1, 1.5 ms"−"1 and 2 ms"−"1) were studied and compared. The minimum time of processing was 17 min when integrated hot air flow and microwave radiation was applied with 2000 W power at the temperature of 70 °C and air velocity of 2 ms"−"1. Furthermore, the minimum value of total energy consumption during entire process of apple slices drying was 2684 kJ which belonged to microwave drying with 2000 W power. - Highlights: • Microwave radiation is implemented to reduce the energy demand for drying. • Simultaneous impact of microwave and hot air on energy and time consumption was analyzed. • Minimum drying time occurs with combined utilization of microwave and hot air. • Thermal efficiency was desirable in low air velocities and high temperatures. • Thermal efficiency of microwave radiation increased by 200% compared to single hot air method.

The sustained effect (12 months) of a single-dose vectored thermal pulsation procedure for meibomian gland dysfunction and evaporative dry eye.

Science.gov (United States)

Blackie, Caroline A; Coleman, Christy A; Holland, Edward J

2016-01-01

To evaluate the sustained effect (up to 1 year) of a single, 12-minute vectored thermal pulsation (VTP) treatment in improving meibomian gland function and dry eye symptoms in patients with meibomian gland dysfunction and evaporative dry eye. The prospective, multicenter, open-label clinical trial included 200 subjects (400 eyes) who were randomized to a single VTP treatment (treatment group) or twice-daily, 3-month, conventional warm compress and eyelid hygiene therapy (control group). Control group subjects received crossover VTP treatment at 3 months (crossover group). Effectiveness measures of meibomian gland secretion (MGS) and dry eye symptoms were evaluated at baseline and 1, 3, 6, 9, and 12 months. Subjects with inadequate symptom relief could receive additional meibomian gland dysfunction therapy after 3 (treatment group) and 6 months (crossover group). At 3 months, the treatment group had greater mean improvement in MGS (Pdry eye symptoms (P=0.0068), compared to controls. At 12 months, 86% of the treatment group had received only one VTP treatment, and sustained a mean improvement in MGS from 6.4±3.7 (baseline) to 17.3±9.1 (Pdry eye symptoms from 44.1±20.4 to 21.6±21.3 (Pdry eye symptoms from 49.1±21.0 to 24.0±23.2 (Pdry eye symptoms, over 12 months. A single VTP treatment provides significantly greater mean improvement in meibomian gland function and dry eye symptoms as compared to a conventional, twice-daily, 3-month regimen. Early VTP intervention for meibomian gland dysfunction is associated with improved treatment outcomes.

Understanding the performance and mechanism of Mg-containing oxides as support catalysts in the thermal dry reforming of methane.

Science.gov (United States)

Khairudin, Nor Fazila; Sukri, Mohd Farid Fahmi; Khavarian, Mehrnoush; Mohamed, Abdul Rahman

2018-01-01

Dry reforming of methane (DRM) is one of the more promising methods for syngas (synthetic gas) production and co-utilization of methane and carbon dioxide, which are the main greenhouse gases. Magnesium is commonly applied in a Ni-based catalyst in DRM to improve catalyst performance and inhibit carbon deposition. The aim of this review is to gain better insight into recent developments on the use of Mg as a support or promoter for DRM catalysts. Its high basicity and high thermal stability make Mg suitable for introduction into the highly endothermic reaction of DRM. The introduction of Mg as a support or promoter for Ni-based catalysts allows for good metal dispersion on the catalyst surface, which consequently facilitates high catalytic activity and low catalyst deactivation. The mechanism of DRM and carbon formation and reduction are reviewed. This work further explores how different constraints, such as the synthesis method, metal loading, pretreatment, and operating conditions, influence the dry reforming reactions and product yields. In this review, different strategies for enhancing catalytic activity and the effect of metal dispersion on Mg-containing oxide catalysts are highlighted.

Chemical and physical pretreatments of fruits and vegetables: Effects on drying characteristics and quality attributes - a comprehensive review.

Science.gov (United States)

Deng, Li-Zhen; Mujumdar, Arun S; Zhang, Qian; Yang, Xu-Hai; Wang, Jun; Zheng, Zhi-An; Gao, Zhen-Jiang; Xiao, Hong-Wei

2017-12-20

Pretreatment is widely used before drying of agro-products to inactivate enzymes, enhance drying process and improve quality of dried products. In current work, the influence of various pretreatments on drying characteristics and quality attributes of fruits and vegetables is summarized. They include chemical solution (hyperosmotic, alkali, sulfite and acid, etc.) and gas (sulfur dioxide, carbon dioxide and ozone) treatments, thermal blanching (hot water, steam, super heated steam impingement, ohmic and microwave heating, etc), and non-thermal process (ultrasound, freezing, pulsed electric field, and high hydrostatic pressure, etc). Chemical pretreatments effectively enhance drying kinetics, meanwhile, it causes soluble nutrients losing, trigger food safety issues by chemical residual. Conventional hot water blanching has significant effect on inactivating various undesirable enzymatic reactions, destroying microorganisms, and softening the texture, as well as facilitating drying rate. However, it induces undesirable quality of products, e.g., loss of texture, soluble nutrients, pigment and aroma. Novel blanching treatments, such as high-humidity hot air impingement blanching, microwave and ohmic heat blanching can reduce the nutrition loss and are more efficient. Non-thermal technologies can be a better alternative to thermal blanching to overcome these drawbacks, and more fundamental researches are needed for better design and scale up.

Degradation Characterization of Thermal Interface Greases

Energy Technology Data Exchange (ETDEWEB)

Major, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Narumanchi, Sreekant V [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Paret, Paul P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Blackman, Gregory [DuPont; Wong, Arnold [DuPont; Meth, Jeffery [DuPont

2018-02-12

Thermal interface materials (TIMs) are used in power electronics packaging to minimize thermal resistance between the heat generating component and the heat sink. Thermal greases are one such class. The conformability and thin bond line thickness (BLT) of these TIMs can potentially provide low thermal resistance throughout the operation lifetime of a component. However, their performance degrades over time due to pump-out and dry-out during thermal and power cycling. The reliability performance of greases through operational cycling needs to be quantified to develop new materials with superior properties. NREL, in collaboration with DuPont, has performed thermal and reliability characterization of several commercially available thermal greases. Initial bulk and contact thermal resistance of grease samples were measured, and then the thermal degradation that occurred due to pump-out and dry-out during temperature cycling was monitored. The thermal resistances of five different grease materials were evaluated using NREL's steady-state thermal resistance tester based on the ASTM test method D5470. Greases were then applied, utilizing a 2.5 cm x 2.5 cm stencil, between invar and aluminum plates to compare the thermomechanical performance of the materials in a representative test fixture. Scanning Acoustic microscopy, thermal, and compositional analyses were performed periodically during thermal cycling from -40 degrees C to 125 degrees C. Completion of this characterization has allowed for a comprehensive evaluation of thermal greases both for their initial bulk and contact thermal performance, as well as their degradation mechanisms under accelerated thermal cycling conditions.

Determination of thermal-diffusive properties of lyophilized food products

International Nuclear Information System (INIS)

Kaplon, J.; Kramkowski, R.; Berdzik, M.

1998-01-01

Experimental results of vacuum freeze drying were presented. Water solutions of skim milk were dried under various pressures and distribution of temperature and moisture as a function of drying time were determined. Unilateral radiant heating of the material was applied. On the basis of experiment results and URIF model of vacuum freeze drying the thermal conductivity and vapour diffusion coefficients in dry layer were determined

Sewage sludge drying process integration with a waste-to-energy power plant.

Science.gov (United States)

Bianchini, A; Bonfiglioli, L; Pellegrini, M; Saccani, C

2015-08-01

Dewatered sewage sludge from Waste Water Treatment Plants (WWTPs) is encountering increasing problems associated with its disposal. Several solutions have been proposed in the last years regarding energy and materials recovery from sewage sludge. Current technological solutions have relevant limits as dewatered sewage sludge is characterized by a high water content (70-75% by weight), even if mechanically treated. A Refuse Derived Fuel (RDF) with good thermal characteristics in terms of Lower Heating Value (LHV) can be obtained if dewatered sludge is further processed, for example by a thermal drying stage. Sewage sludge thermal drying is not sustainable if the power is fed by primary energy sources, but can be appealing if waste heat, recovered from other processes, is used. A suitable integration can be realized between a WWTP and a waste-to-energy (WTE) power plant through the recovery of WTE waste heat as energy source for sewage sludge drying. In this paper, the properties of sewage sludge from three different WWTPs are studied. On the basis of the results obtained, a facility for the integration of sewage sludge drying within a WTE power plant is developed. Furthermore, energy and mass balances are set up in order to evaluate the benefits brought by the described integration. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of a functional soy product with addition of soy fiber and fermented with probiotic kefir culture

Directory of Open Access Journals (Sweden)

Tahis Regina Baú

2014-06-01

Full Text Available The objective of this study was to evaluate the chemical, sensory properties and stability of a functional soy product with soy fiber and fermented with probiotic kefir culture. The product was characterized by the chemical composition, color and sensory analysis. The stability of the product was evaluated by pH, acidity, viscosity, firmness, syneresis measurements and cells counts. The functional soy product presented better chemical composition and difference in color compared to the fermented product without fiber. Sensory analysis showed that the functional soy product had good acceptance and had better firmness and reduced syneresis compared to fermented product without fiber. The lactic acid bacteria counts decreased slightly during 28 days at 4°C of the storage and the product showed good microbiological stability. The functional soy product due to high Lactococcus lactis counts could be considered as a probiotic for the entire storage period.

Phenolic products of radiation-thermal degradation of lignin as inhibitors for thermal polymerization of styrene

International Nuclear Information System (INIS)

Shalyminova, D.P.; Cherezova, E.N.; Ponomarev, A.V.; Tananaev, I.G.

2008-01-01

Fast 8-MeV electrons were used for the heating and dry distillation of hydrolytic lignin. The resulting tar differed in composition from that of the conventional dry distillation and was composed primarily of methoxyphenols. Guaiacol and creosol were the prevalent components in the fraction with the boiling range 80-235 deg C. It was shown that the tar effectively inhibits the thermal polymerization of styrene, with the inhibiting activity being higher than that of the commercial inhibitors Agidol 1 and Agidol 2. In the presence of 0.025 wt % tar, the induction period of the thermal polymerization of styrene at 120 deg C was at least 120 min [ru

Porcelain tiles by the dry route

International Nuclear Information System (INIS)

Melchiades, F. G.; Daros, M. T.; Boschi, A. O.

2010-01-01

In Brazil, the second largest tile producer of the world, at present, 70% of the tiles are produced by the dry route. One of the main reasons that lead to this development is the fact that the dry route uses approximately 30% less thermal energy them the traditional wet route. The increasing world concern with the environment and the recognition of the central role played by the water also has pointed towards privileging dry processes. In this context the objective of the present work is to study the feasibility of producing high quality porcelain tiles by the dry route. A brief comparison of the dry and wet route, in standard conditions industrially used today to produce tiles that are not porcelain tiles, shows that there are two major differences: the particle sizes obtained by the wet route are usually considerably finer and the capability of mixing the different minerals, the intimacy of the mixture, is also usually better in the wet route. The present work studied the relative importance of these differences and looked for raw materials and operational conditions that would result in better performance and glazed porcelain tiles of good quality. (Author) 7 refs.

Hot dry rock heat mining

International Nuclear Information System (INIS)

Duchane, D.V.

1992-01-01

Geothermal energy utilizing fluids from natural sources is currently exploited on a commercial scale at sites around the world. A much greater geothermal resource exists, however, in the form of hot rock at depth which is essentially dry. This hot dry rock (HDR) resource is found almost everywhere, but the depth at which usefully high temperatures are reached varies from place to place. The technology to mine the thermal energy from HDR has been under development for a number of years. Using techniques adapted from the petroleum industry, water is pumped at high pressure down an injection well to a region of usefully hot rock. The pressure forces open natural joints to form a reservoir consisting of a small amount of water dispensed in a large volume of hot rock. This reservoir is tapped by second well located at some distance from the first, and the heated water is brought to the surface where its thermal energy is extracted. The same water is then recirculated to mine more heat. Economic studies have indicated that it may be possible to produce electricity at competitive prices today in regions where hot rock is found relatively close to the surface

Freeze-drying-induced changes in the properties of graphene oxides

International Nuclear Information System (INIS)

Ham, Heon; Van Khai, Tran; Gil Na, Han; Jung Kwon, Yong; Yeon Cho, Hong; Woo Kim, Hyoun; Park, No-Hyung; So, Dae Sup; Lee, Joon-Woo

2014-01-01

We have characterized and evaluated changes in graphene oxide (GO) induced by means of freeze-drying. In order to evaluate these changes, we investigated the effects of freeze-drying and chemical reduction processes on the structure, morphology, chemical composition, and Raman properties of GO and reduced GO. The freeze-dried GO had a pore structure, maintaining a pored morphology even after thermal annealing. The freeze-dried samples were composed of a single folded nanosheet or a few nanosheets stacked and folded. The oxygen-containing functional groups were removed not only during the freeze-drying but also during the reduction processes, with an accompanying decrease in the average size of the sp 2 carbon domain (i.e. an increase in the I D /I G value). (papers)

Hot Dry Rock Geothermal Energy Development Program

Energy Technology Data Exchange (ETDEWEB)

Smith, M.C.; Hendron, R.H.; Murphy, H.D.; Wilson, M.G.

1989-12-01

During Fiscal Year 1987, emphasis in the Hot Dry Rock Geothermal Energy Development Program was on preparations for a Long-Term Flow Test'' of the Phase II'' or Engineering'' hot dry rock energy system at Fenton Hill, New Mexico. A successful 30-day flow test of the system during FY86 indicated that such a system would produce heat at a temperature and rate that could support operation of a commercial electrical power plant. However, it did not answer certain questions basic to the economics of long-term operation, including the rate of depletion of the thermal reservoir, the rate of water loss from the system, and the possibility of operating problems during extended continuous operation. Preparations for a one-year flow test of the system to answer these and more fundamental questions concerning hot dry rock systems were made in FY87: design of the required surface facilities; procurement and installation of some of their components; development and testing of slimline logging tools for use through small-diameter production tubing; research on temperature-sensitive reactive chemical tracers to monitor thermal depletion of the reservoir; and computer simulations of the 30-day test, extended to modeling the planned Long-Term Flow Test. 45 refs., 34 figs., 5 tabs.

Grapes ( Vitis vinifera) drying by semitransparent photovoltaic module (SPVM) integrated solar dryer: an experimental study

Science.gov (United States)

Tiwari, Sumit; Tiwari, G. N.

2018-06-01

In present research paper, semi-transparent photovoltaic module (SPVM) integrated greenhouse solar drying system has been used for grapes ( Vitis vinifera) drying. Based on hourly experimental information namely solar intensity, moisture evaporated, ambient air temperature, grape surface temperatures, relative humidity and greenhouse air temperature etc. heat and mass transfer coefficient for the SPVM drying system have been evaluated. It has been seen that the convective heat transfer coefficients for grapes found between 3.1-0.84 W/m2 K. Also, there is a fair agreement between theoretical and practical mass transfer (moisture evaporated) during drying of grapes with a correlation coefficient (r) and root mean square percentage deviation (e) of 0.88 and 11.56 respectively. Further, nonlinear regression procedure has been used to fit various drying models namely Henderson and Pabis model, Newton's model, and Page's model. From the analysis, it was found that Page's model is best fitted for grapes drying in SPV greenhouse as well as open sun drying. Further, net electrical energy, thermal energy and equivalent thermal energy were found to be 3.61, 17.66 and 27.15 kWh during six days of drying respectively.

Grapes (Vitis vinifera) drying by semitransparent photovoltaic module (SPVM) integrated solar dryer: an experimental study

Science.gov (United States)

Tiwari, Sumit; Tiwari, G. N.

2017-12-01

In present research paper, semi-transparent photovoltaic module (SPVM) integrated greenhouse solar drying system has been used for grapes (Vitis vinifera) drying. Based on hourly experimental information namely solar intensity, moisture evaporated, ambient air temperature, grape surface temperatures, relative humidity and greenhouse air temperature etc. heat and mass transfer coefficient for the SPVM drying system have been evaluated. It has been seen that the convective heat transfer coefficients for grapes found between 3.1-0.84 W/m2 K. Also, there is a fair agreement between theoretical and practical mass transfer (moisture evaporated) during drying of grapes with a correlation coefficient (r) and root mean square percentage deviation (e) of 0.88 and 11.56 respectively. Further, nonlinear regression procedure has been used to fit various drying models namely Henderson and Pabis model, Newton's model, and Page's model. From the analysis, it was found that Page's model is best fitted for grapes drying in SPV greenhouse as well as open sun drying. Further, net electrical energy, thermal energy and equivalent thermal energy were found to be 3.61, 17.66 and 27.15 kWh during six days of drying respectively.

A numerical analysis method on thermal and shrinkage stress of concrete

International Nuclear Information System (INIS)

Takiguchi, Katsuki; Hotta, Hisato

1991-01-01

Thermal stress often causes cracks in large scale concrete such as that for dam construction. The drying shrinkage of concrete causes cracks in concrete structures. These thermal stress and drying shrinkage stress may be the main reasons cracks occur in concrete, however there is few research which dealt with both stresses together. The problems on the thermal stress and the drying shrinkage are not independent, and should be dealt with together, because both temperature and water content of concrete affect hydration reaction, and the degree of hydration determines all the characteristics of concrete at early age. In this study, the degree of hydration is formulated experimentally, and a numerical stress analysis method taking the hydration reaction in consideration is presented. The formulation of the rate of hydration reaction, the method of analyzing thermal and drying shrinkage stresses, the analytical results for a concrete column and the influence that continuous load exerted to the tensile strength of concrete are reported. The relatively high stress nearly equal to the tensile strength of concrete arises near the surface. (K.I.)

Effect of solar radiation on drying house performance

International Nuclear Information System (INIS)

Rachmat, R.

2000-01-01

Solar drying is one of thermal utilization where radiation energy can be utilized efficiently. Solar drying of all sorts of agricultural products have been thoroughly studied and reported in literature, but brown rice drying system has not yet done as many as other products. The aim of the present study is to investigate the effect of solar radiation on drying house performance and brown rice drying characteristics. A construction of drying house is made from FRP sheets with 30 deg. of root slope faces southern part and inside the drying house is installed a flat bed dryer. The site of construction has 136 deg. 31.4'E in longitude and 34 deg. 43.8N in latitude with 3 m in elevation from sea level. The investigated parameters are global solar radiation, absorbed and net radiation and brown rice drying characteristics. The results showed that in unload condition, the air temperature inside drying house was higher (10 deg. C - 12 deg. C) than ambient air when there was not collector and temperature rise become higher (16 deg. C) when there was a black FRP collector inside drying house. The effect of solar radiation on temperature rise has the trend as a linear function. The heat collection efficiency of drying house with black FRP collector was two times higher (36.9 percent) than that without collector (16.3 percent). These phenomena exhibited significant result of collector utilization to the advantageous condition for a drying purpose [in

Dimensioning, construction and commissioning of a coffee beans drying system with use of solar collectors

International Nuclear Information System (INIS)

Mora Vindas, Allan Gerardo

2014-01-01

A system of low-cost solar drying of coffee beans is dimensioned, built and commissioned by using solar collectors based on recycled aluminum cans. The information is collected from literature about the drying of coffee, types of drying and the various types of solar dryers.The coffee beans drying system is conceptualized and sized based on a solar collector constructed of aluminum cans as solar radiation absorbing material. The grain drying system is then built in coffee benefit CoopeTarrazu to all provided by the company and help materials and labor facilities. A guide to implementation of solar drying technology with general information is tailored to implement, select, build and maintain a solar grain dryer in Central America. The launch of the drying system was made by checking the proper functioning of the system and measurement instruments variables selected to calculate the efficiency of the system. The drying system is tested with a load of 45 kg of coffee bean, using a flow of air through natural convection to operate the system with the exclusive use of renewable energy. The grain is drying from a humidity of 50% (b.n), up to a humidity between 11% and 13% (b.n), which is the range generally used for the safe storage of grain. Facts of solar radiation, temperature, air velocity, relative humidity and grain humidity were taken to determine the behavior of the sized system. The maximum thermal efficiency achieved by the solar collector is determined constructed of 18%, with an air flow of 0.013 kg/s and a solar radiation 1138 W/m 2 . The average drying efficiency during experimentation was 17.8%, which is among the range of efficiencies for the type of drying equipment. Best thermal efficiencies were obtained from the solar collector built that the commercial solar collector compared. Controlling the flow of air into the equipment is recommended in order to improve the thermal efficiency and drying equipment, using blowers, fans or induced draft chimney

Spray-Dried Cellulose Nanofibril-Reinforced Polypropylene Composites for Extrusion-Based Additive Manufacturing: Nonisothermal Crystallization Kinetics and Thermal Expansion

Directory of Open Access Journals (Sweden)

Lu Wang

2018-02-01

Full Text Available Isotactic polypropylene (iPP is a versatile polymer. It accounts for the second-largest polymer consumption worldwide. However, iPP is difficult to 3D print via extrusion-based processing. This is attributable to its rapid crystallization rate. In this study, spray-dried cellulose nanofibrils (SDCNF and maleic anhydride polypropylene (MAPP were investigated to reveal their effects on the nonisothermal crystallization kinetics and thermal expansion of iPP. SDCNF at 3 wt % and 30 wt % accelerated the crystallization rate of iPP, while SDCNF at 10 wt % retarded the crystallization rate by restricting crystal growth and moderately increasing the nucleation density of iPP. Additionally, adding MAPP into iPP/SDCNF composites accelerated the crystallization rate of iPP. The effective activation energy of iPP increased when more than 10 wt % SDCNF was added. Scanning electron microscopy and polarized light microscopy results indicated that high SDCNF content led to a reduced gap size among SDCNF, which hindered the iPP crystal growth. The coefficient of thermal expansion of iPP/SDCNF10% was 11.7% lower than the neat iPP. In summary, SDCNF, at 10 wt %, can be used to reduce the warping of iPP during extrusion-based additive manufacturing.

Comparison of different drying methods on the physical properties, bioactive compounds and antioxidant activity of raspberry powders.

Science.gov (United States)

Si, Xu; Chen, Qinqin; Bi, Jinfeng; Wu, Xinye; Yi, Jianyong; Zhou, Linyan; Li, Zhaolu

2016-04-01

Dehydration has been considered as one of the traditional but most effective techniques for perishable fruits. Raspberry powders obtained after dehydration can be added as ingredients into food formulations such as bakery and dairy products. In this study, raspberry powders obtained by hot air drying (HAD), infrared radiation drying (IRD), hot air and explosion puffing drying (HA-EPD), infrared radiation and microwave vacuum drying (IR-MVD) and freeze drying (FD) were compared on physical properties, bioactive compounds and antioxidant activity. Drying techniques affected the physical properties, bioactive compounds and antioxidant activity of raspberry powders greatly. FD led to significantly higher (P drying methods. However, thermal drying techniques, especially combined drying methods, were superior to FD in final total polyphenol content, total flavonoid content and antioxidant activity. The combined drying methods, especially IR-MVD, showed the highest total polyphenol content (123.22 g GAE kg(-1) dw) and total flavonoid content (0.30 g CAE kg(-1) dw). Additionally, IR-MVD performed better in antioxidant activity retention. Overall, combined drying methods, especially IR-MVD, were found to result in better quality of raspberry powders among the thermal drying techniques. IR-MVD could be recommended for use in the drying industry because of its advantages in time saving and nutrient retention. © 2015 Society of Chemical Industry.

Thermal conductivity of compacted bentonite as a buffer material for a high-level radioactive waste repository

International Nuclear Information System (INIS)

Lee, Jae Owan; Choi, Heuijoo; Lee, Jong Youl

2016-01-01

Highlights: • The thermal conductivities were measured under various disposal conditions. • They were significantly influenced by the water content and dry density. • They were not sensitive to the temperature and the anisotropic structure. • A new model of thermal conductivity was proposed for the thermal analysis. - Abstract: Bentonite buffer is one of the major barrier components of a high-level radioactive waste (HLW) repository, and the thermal conductivity of the bentonite buffer is a key parameter for the thermal performance assessment of the HLW repository. This study measured the thermal conductivity of compacted bentonite as a buffer material and investigated its dependence upon various disposal conditions: the dry density, water content, anisotropic structure of the compacted bentonite, and temperature. The measurement results showed that the thermal conductivity was significantly influenced by the water content and dry density of the compacted bentonite, while there was not a significant variation with respect to the temperature. The anisotropy of the thermal conductivity had a negligible variation for an increasing dry density. The present study also proposed a geometric mean model of thermal conductivity which best fits the experimental data.

The postirradiation examination of the DC [Dry Capsule] melt dynamics experiments

International Nuclear Information System (INIS)

Fryer, C.P.; Hitchcock, J.T.

1988-07-01

The Dry Capsule experiment series investigates the coolability of dry fast reactor core debris through nuclear heating of actual reactor materials in order to obtain the thermal properties of dry debris, the nature of the transition from a debris bed to a molten pool, and the thermal and kinetic behavior of molten pools. The purpose is to develop a data base in support of model development. The work is jointly sponsored by the US Nuclear Regulatory Commission (USNRC), the Power Reactor and Nuclear Fuel Development Corporation (PNC, Japan), and Joint Research Centre, Ispra (EURATOM). This report provides a brief description of the two experiments in the Dry Capsule series and presents the results of the postirradiation examination. These tests investigated dry debris beds (/approximately/2kg) composed of pure UO 2 and mixed UO 2 and stainless steel. The beds were taken into melt to observe the growth of a molten pool in the UO 2 bed and the agglomeration and migration of steel in a composite bed. The peak measured temperature in the UO 2 bed was above 3100/degree/C. Approximately 50 percent of the urania formed a molten pool. Surrounding the molten pool and an overlying void was a high density urania crust. Lenticular pore formation and migration caused by urania vapor transport in the strong thermal gradient were seen in the urania crust. In the mixed UO 2 and steel bed, the peak measured temperature was 2600/degree/ C. All of the steel had been molten. Steel and urania migration were observed; both were thought to be caused by vapor transport mechanisms

Characterization of dextransucrase from Leuconostoc mesenteroides T3, water kefir grains isolate

Directory of Open Access Journals (Sweden)

Miljković Miona G.

2017-01-01

Full Text Available The production of dextransucrase (DS by Leuconostoc mesenteroides T3, novel isolate from water kefir grain, was studied and optimized. Bacterial supernatant reached activity of 3.1 U/ml when the culture was grown at 23 C and under static culture condition using classical Tsuchiya medium for DS production. The increase of sucrose concentration to 7% led to an increase of DS activity by 52% compared to the control. Medium with 2% beef extract and 1% yeast extract resulted in 4.52 U/ml, which was 47% higher than in the control (with 2% yeast extract. Finally, the increase of K2HPO4 concentration from 2 to 3% resulted in the increased enzyme activity by 28%. Enzyme purified by polyethylene glycol 400 fractionation displayed maximum activity at 30°C and pH 5.4. Zymogram analysis confirmed the presence of DS of approximately 180 kDa. The addition of divalent cations Ca2+, Mg2+, Fe2+ and Co2+ led to a minor increase of DS activity, while the addition of Mn2+ was the most prominent with 73% increase. These findings classify dextransucrase from Leuconostoc mesenteroides T3 as promising candidate for production of dextran, which has numerous applications in various industries. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. TR 31035