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1

2-acetyl-1-pyrroline - key aroma compound in Mediterranean dried sausages  

In a study characterising sausage types from various parts of Europe, ten Mediterranean and Northern European fermented, dried sausages were compared using static headspace gas chromatography-olfactometry and a sniffing panel of five members. The greatest difference between the Northern and Southern types were attributed to a burned coffee odour from smoke in the smoked sausages and a popcorn note in the Mediterranean products covered with mould. The two compounds were 2-furfurylthiol and 2-acetyl-1-pyrroline, respectively. An analysis of five dried, moulded sausages showed that the surface edge of the sausages contained higher amounts of 2-acetyl-1-pyrroline than the core, indicating that the mould growing on the surface of Mediterranean products produces 2-acetyl-1-pyrroline.

2

Influence of Endogenous Ferulic Acid in Whole Wheat Flour on Bread Crust Aroma.  

The influence of wheat flour type (refined (RWF)/whole (WWF)) on bread crust aroma was investigated. Differences were characterized by aroma extract dilution analysis and quantified utilizing stable isotope surrogate standards. For RWF breads, five aroma compounds were higher in concentration, 2-acetyl-1-pyrroline, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 2-phenylethanol, 2-acetyl-2-thiazoline, and 2,4-dihyroxy-2,5-dimethyl-3(2H)-furanone, by 4.0-, 3.0-, 2.1-, 1.7-, and 1.5-fold, respectively, whereas three compounds were lower, 2-ethyl-3,5-dimethylpyrazine, (E,E)-2,4-decadienal, and (E)-2-nonenal by 6.1-, 2.1-, and 1.8-fold, respectively. A trained sensory panel reported the perceived aroma intensity of characteristic fresh refined bread crust aroma was significantly higher in RWF compared to WWF crust samples. Addition of 2-acetyl-1-pyrroline, 4-hydroxy-2,5-dimethyl-3(2H)-furanone, 2-phenylethanol, 2-acetyl-2-thiazoline, and 2,4-dihyroxy-2,5-dimethyl-3(2H)-furanone to the WWF crust (at concentrations equivalent to those in the RWF crust) increased the intensity of the fresh refined bread crust aroma attribute; no significant difference was reported when compared to RWF crust. The liberation of ferulic acid from WWF during baking was related to the observed reduction in these five aroma compounds and provides novel insight into the mechanisms of flavor development in WWF bread. PMID:23106092

3

Characterization of dried whey protein concentrate and isolate flavor.  

The flavor of whey protein concentrates (WPC 80) and whey protein isolates (WPI) was studied using instrumental and sensory techniques. Four WPC 80 and 4 WPI, less than 3 mo old, were collected in duplicate from 6 manufacturers in the United States. Samples were rehydrated and evaluated in duplicate by descriptive sensory analysis. Duplicate samples with internal standards were extracted with diethyl ether. Extracts were then distilled to remove nonvolatile material using high vacuum distillation. Volatile extracts were analyzed using gas chromatography/olfactometry with post peak intensity analysis and aroma extract dilution analysis. Compounds were identified by comparison of retention indices, odor properties, and gas chromatography/mass spectrometry against reference standards. Whey proteins exhibited sweet aromatic, cardboard/wet paper, animal/wet dog, soapy, brothy, cucumber, and cooked/milky flavors, along with the basic taste bitter, and the feeling factor astringency. Key volatile flavor compounds in WPC 80 and WPI were butanoic acid (cheesy), 2-acetyl-1-pyrroline (popcorn), 2-methyl-3-furanthiol (brothy/burnt), 2,5-dimethyl-4-hydroxy-3-(2H)-furanone (maple/spicy), 2-nonenal (fatty/old books), (E,Z)-2,6-nonadienal (cucumber), and (E,Z)-2,4-decadienal (fatty/oxidized). This baseline data on flavor and flavor sources in whey proteins will aid ongoing and future research and will help to identify the most appropriate whey ingredients to use to control or minimize flavor variability in whey enhanced products. PMID:16230688

4

Variation of 2-Acetyl-1-Pyrroline Concentration in Aromatic Rice Grains Collected in the Same Region in Japan and Factors Affecting Its Concentration  

Aroma strength of aromatic rice varies with the genetic and environmental conditions. We determined the concentration of 2-acetyl-1-pyrroline (2AP), a key compound of the aroma of aromatic rice, in 62 samples of rice grains (brown rice) from 'Hieri' produced by 17—24 farmers in 3 years in the Kubokawa area of Kochi Prefecture, Japan. Many of them showed similar values and the standard deviations were 27—31%. However, a few samples showed extremely high (200%) or low (60%) 2AP concentrations compared to the individual year averages (100%). The influence of harvest time and temperature during ripening on the 2AP concentration in the brown rice was also examined using two cultivars. During grain development in an early-heading cultivar 'Miyakaori' , the 2AP concentration in the brown rice reached a peak at 4 or 5 weeks after heading (WAH) and then decreased rapidly to 20% of the maximum at 7 or 8 WAH. In a late-heading cultivar 'Hieri', the 2AP concentration peaked at 4 WAH then gradually decreased to 40% of the maximum at 8 WAH. The 2AP concentration was higher in brown rice ripened at a low temperature (day : 25°C/night : 20°C) than that ripened at a high temperature (day: 35°C/night: 30°C) in both a short-grain cultivar 'Hieri' and a long-grain cultivar 'Sari Queen'.   

5

Sensory characteristics of European, dried, fermented sausages and the correlation to volatile profile  

In the European FAIR-project: Control of Bioflavour and Safety in Northern and Mediterranean Fermented Meat Products (FAIR-CT97-3227) four different sausage types were manufactured in five replicates and characterised by sensory and analytical means. The objective of the present study was to characterise the flavour pattern of the FAIR sausages with regards to sensory perceived compounds and volatile/sensory profiles. According to gas chromatography-olfactometry the greatest differences between the Northern and Mediterranean sausages were attributed to coffee/roasted, phenolic and vinegar odours in the smoked sausages and a popcorn note in the Mediterranean products covered with mould. The compounds were 2-furfurylthiol, guaiacol, acetic acid and 2-acetyl-1-pyrroline, respectively. Sausages added garlic contained two specific odours with salami/onion-like notes. The odours were attributed to allylmercaptane and methylthiirane. Correlation of sensory and volatile profile showed that garlic flavour correlated with sulphur compounds from garlic, smoked flavour with most of the cyclic compounds (furanes, phenols etc.), acid flavour with the acids (acetic, butanoic and hexanoic acid), spice and piquante flavour with the terpenes, rancid flavour with hexanal, octanal, nonanal and decanal and maturity with ethyl esters and methyl-ketones.

6

Identification of Elite Population of Pandanus amaryllifolius Roxb. for Higher 2-Acetyl-1-pyrroline and Other Volatile Contents by HS-SPME/GC-FID from Peninsular India  

The clonal populations of Pandanus amaryllifolius Roxb. from the western and eastern coastal regions of India were screened for 2-acetyl-1-pyrroline (2AP) and other volatile contents by HS-SPME/GC-FID. The analyses revealed that irrespective of locality, 19 volatile compounds were always detected in all population. 2AP, nonanal, phytol, 2-hexenal, 2,6-nonadienal and hexanal were found to be the major contributors. The Palghar locality from Maharashtra state was found to harbour the highest amount of 2AP (12.25 ppm), nonanal (2.97 ppm) and 2-hexenal (25.70 ppm). Phytol, 2,6-nonadienal and hexanal were highest in the Alibag locality (13.96 ppm), Chiplun locality (6.47 ppm) of Maharashtra state and the Bailhongal locality (6.25 ppm) of Karnataka state, respectively. Minor components acc...

7

Inhibitory Effect of Aroma on the Bitterness of Branched-Chain Amino Acid Solutions  

Nutritional products for patients with liver failure available on the Japanese market contain many branched-chain amino acids (BCAAs) such as L-leucine, L-isoleucine, and L-valine, which not only have a bitter taste but also strong, unpleasant odours, leading to low palatability. The palatability of these nutritional products can be significantly improved by the addition of flavoured powders containing various kinds of tastants (sucrose, citric acid, etc.) and odourants (fruit, coffee aromas, etc.). The specific effects of the aroma of flavoured powders have not yet been clearly evaluated. In the present article, the inhibitory effect of aroma on the bitterness of BCAA solutions was examined. The bitterness intensity of a BCAA solution at the same concentration as Aminoleban® EN was defined as 3.5 (measured by a previously described gustatory sensation method). The bitterness threshold of a BCAA standard solution without added aroma was estimated to be 1.87, while those of BCAA solutions containing green-tea, coffee, apple, vanilla, or strawberry aromas were 2.02, 1.98, 2.35, 2.40 and 2.87, respectively, when evaluated by the probit method. This shows that the addition of an aroma can elevate the bitterness threshold in human volunteers. The green-tea and coffee aromas predominantly evoked bitterness, while the vanilla aroma predominantly evoked sweetness. Apple and strawberry aromas evoked both sweetness and sourness, with the apple aroma having stronger sourness and the strawberry aroma stronger sweetness. Thus, a ‘sweet’ aroma suppresses the bitterness of BCAA, with coexisting sourness also participating in the bitterness inhibition.   

8

Media components and amino acid supplements influencing the production of fruity aroma by Geotrichum candidum/ Influência da composição do meio de cultivo e da suplementação com aminoácidos na produção de aroma frutal por Geotrichum candidum  

Abstract in portuguese Geotrichum candidum foi cultivado em diversos meios de cultura contendo sacarose ou melaço e milhocina ou peptona e a produção de aroma frutal foi verificada através de avaliação sensorial e cromatografia gasosa acoplada a espectrometria de massas. Os meios contendo melaço, peptona e leucina, valina ou alanina apresentaram os melhores resultados e a presença de diversos ésteres foi consistente com a formação de aroma frutal. Abstract in english The ability of Geotrichum candidum to produce fruity aroma in food grade sucrose, molasses, corn steep liquor and peptone based culture media was tested by sensory evaluation and analyzed by gas chromatography mass spectrometry. A strong and sweet fruity aroma was produced from molasses, with peptone or corn steep liquor stimulating aroma production. Molasses with peptone supplemented with leucine, valine, or alanine yielded better fruity aroma production and the presence of many esters was consistent with the fruity aroma production.

9

Fruity aromas production in solid state fermentation by the fungus Ceratocystis fimbriata International training course on solid state fermentation  

Solid state fermentation (SSF) has been studied for enzymes, antibiotics, alcohol production or for protein enrichment, but few papers report the production of aromas by such a process. In this work, the study of the production of fruity aromas in SSF by the fungus #Ceratocystis fimbriata$ is presen...

10

Biochemical and enzymatic study of rice BADH wild-type and mutants: an insight into fragrance in rice.  

Betaine aldehyde dehydrogenase 2 (BADH2) is believed to be involved in the accumulation of 2-acetyl-1-pyrroline (2AP), one of the major aromatic compounds in fragrant rice. The enzyme can oxidize ?-aminoaldehydes to the corresponding ?-amino acids. This study was carried out to investigate the function of wild-type BADHs and four BADH2 mutants: BADH2_Y420, containing a Y420 insertion similar to BADH2.8 in Myanmar fragrance rice, BADH2_C294A, BADH2_E260A and BADH2_N162A, consisting of a single catalytic-residue mutation. Our results showed that the BADH2_Y420 mutant exhibited less catalytic efficiency towards ?-aminobutyraldehyde but greater efficiency towards betaine aldehyde than wild-type. We hypothesized that this point mutation may account for the accumulation of ?-aminobutyraldehyde/?(1)-pyrroline prior to conversion to 2AP, generating fragrance in Myanmar rice. In addition, the three catalytic-residue mutants confirmed that residues C294, E260 and N162 were involved in the catalytic activity of BADH2 similar to those of other BADHs. PMID:21959793

11

Delta1-pyrroline-5-carboxylic acid formed by proline dehydrogenase from the Bacillus subtilis ssp. natto expressed in Escherichia coli as a precursor for 2-acetyl-1-pyrroline.  

Proline dehydrogenase (PRODH) catalyzes the biosynthesis of Delta1-pyrroline-5-carboxylic acid (P5C). The Bacillus subtilis subsp. natto gene for the proline dehydrogenase (BnPRODH) was cloned and expressed in Escherichia coli. Nucleotide sequence analysis of the clone revealed an open-reading frame that encodes 302 amino acid polypeptide with a calculated molecular mass of 34.5 kDa. The deduced amino acid sequence showed sequence similarity to bacterial PRODH and PutA of E. coli. The BnPRODH gene was cloned into pET21b and was expressed at a high level in E. coli BL21(DE3). The expressed protein was purified by using nickel ion affinity column chromatography to homogeneity before characterization. The purified recombinant BnPRODH was used to produce P5C. Model system composed of P5C and methylglyoxal was set up to study the formation of 2-acetyl-1-pyrroline. Our data showed that P5C, derived from the conversion of l-proline by the purified recombinant PRODH, might react directly with methylglyoxal to form 2-AP. P5C/methylglyoxal pathway represents the first report of a biological mechanism by which 2-AP may be synthesized in vitro by PRODH. PMID:17536821

12

Cloning and Inactivation of a Branched-Chain-Amino-Acid Aminotransferase Gene from Staphylococcus carnosus and Characterization of the Enzyme  

Staphylococcus carnosus and Staphylococcus xylosus are widely used as aroma producers in the manufacture of dried fermented sausages. Catabolism of branched-chain amino acids (BCAAs) by these strains contributes to aroma formation by production of methyl-branched aldehydes and carboxy acids. The fir...

13

Sensory profile of breast meat from broilers reared in an organic niche production system and conventional standard broilers  

BACKGROUND: Breast meat from broilers produced in very different production systems may vary considerable in sensory profile, which may affect consumer interests. In this study the aim was to evaluate differences in the sensory profiles of breast meat from five broiler products: two conventional standard products (A and B) and three organic niche genotypes (I657, L40 and K8) reared in an apple orchard. RESULTS: Thirteen out of 22 sensory attributes differed significantly between the products. The aroma attributes ‘chicken’, ‘bouillon’ and ‘fat’ scored highest and the ‘iron/liver’ aroma lowest for the niche products. The meat was more ‘tender’, ‘short’ and ‘crumbly’ and less ‘hard’ and ‘stringy’ in the standard products than in one or more of the niche products. Product ‘I 657’ was less ‘juicy’ than the rest. Products ‘I 657’ and ‘L 40’ were more ‘cohesive’ and tasted more ‘sourish’ and less of ‘sweet/maize’ than the standard products. The ‘overall liking’ score was significantly higher for the ‘K 8’ product than for the ‘Standard A’ and ‘L 40’ products. The ‘overall liking’ score was significantly correlated with the scores for aroma and taste of ‘chicken’, ‘umami/bouillon’, ‘iron/liver’ and ‘fat’ aroma. CONCLUSION: The sensory profiles differed particularly between conventional standard broilers and organic niche broilers, although differences were also found between breeds. The present study indicates that aroma and taste attributes were more important for the assessors than meat ‘tenderness’ for the overall liking of broiler meat.

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Effect of the Variables Time and Temperature on Volatile Compounds Extraction of Salami by Solid Phase Microextraction  

The aim of this study was to determine the experimental conditions for extracting volatile compounds present in the headspace of a salami sample by solid phase microextraction (Carboxen/PDMS fiber), monitoring the individual aromas of the extracts directly in order to maintain the original aroma of the product. Additionally, extracts were analyzed in gas chromatograph equipped with flame ionization detector and mass spectrometer (GC-FID and GC/MS). Volatile compounds were separated in polar phase capillary column (DB-Wax). Response Surface Methodology was used to explain the effects of both time and temperature on the salami aroma and on the instrumental measurements. Trained judges analyzed the intensity of a characteristic aroma from 12 salami extracts directly in olfactometer coupled wi...

15

[The composition of volatile components of cepe (Boletus edulis) and oyster mushrooms (Pleurotus ostreatus)].  

The composition of aroma compounds in cooked and canned cepe (Boletus edulis) and in cooked oyster mushrooms (Pleurotus ostreatus) is studied using capillary gas chromatography and chromatography-mass spectrometry. It is found that unsaturated alcohols and ketones containing eight atoms of carbon determine the aroma of raw mushrooms and take part in the formation of the aroma of cooked mushrooms as well. The content of these compounds was the highest in canned cepes. In oyster mushrooms, the concentration of these alcohols and ketones was lower in comparison with cepes. The content of aliphatic and aromatic aldehydes was much higher in oyster mushrooms. Volatile aliphatic and heterocyclic Maillard reaction products and isomeric octenols and octenones formed the aroma of cooked and canned mushrooms. PMID:19382709

16

The composition of volatile components of cepe (Boletus edulis) and oyster mushrooms (Pleurotus ostreatus)  

The composition of aroma compounds in cooked and canned cepe (Boletus edulis) and in cooked oyster mushrooms (Pleurotus ostreatus) is studied using capillary gas chromatography and chromatographymass spectrometry. It is found that unsaturated alcohols and ketones containing eight atoms of carbon determine the aroma of raw mushrooms and take part in the formation of the aroma of cooked mushrooms as well. The content of these compounds was the highest in canned cepes. In oyster mushrooms, the concentration of these alcohols and ketones was lower in comparison with cepes. The content of aliphatic and aromatic aldehydes was much higher in oyster mushrooms. Volatile aliphatic and heterocyclic Maillard reaction products and isomeric octenols and octenones formed the aroma of cooked and canned mu...

17

Desenvolvimento do perfil sensorial e avaliação sensorial/instrumental de suco de maracujá/ Sensory profile development and sensory/instrumental passion fruit juice evaluation  

Abstract in portuguese As mais importantes frutas tropicais na categoria de sucos são maracujá e manga, especialmente desejadas por sua impressão aromática e intensa. O aroma e o sabor são resultados da presença de numerosos constituintes que se encontram em concentrações variáveis, extremamente sensíveis às mudanças durante o tratamento térmico na produção de suco. Há a necessidade do desenvolvimento dos perfis sensorial e de cor, que podem ser alterados durante o processamento (more) do suco. O objetivo deste trabalho foi desenvolver esses perfis e avaliar os sucos de maracujá entamborado: despolpado, pasteurizado, entamborado e congelado); pronto para beber (formulado com açúcar e água); e pasteurizado. Treze atributos compuseram o perfil sensorial. O experimento de Análise Descritiva Quantitativa foi delineado com 2 fatores, sucos e provadores. Os resultados foram também submetidos a uma análise de componentes principais. Houve diferença significativa entre os três sucos nos atributos sensoriais, exceto para aromas de maracujá e doce. O aroma artificial, e os aromas e os sabores de cozido e fermentado aumentaram significativamente no suco processado. Os dois primeiros componentes principais concentraram 57% da variação nos atributos sensoriais. Os parâmetros de cor, à exceção do turbidez, apresentaram variações significativas entre os sucos. O suco entamborado foi o mais escuro. A intensidade de vermelho nos sucos entamborado e formulado foi similar, menos acentuada no pasteurizado, enquanto a intensidade de amarelo foi mais acentuada no formulado, decrescendo nos pasteurizado e entamborado. Abstract in english The most important tropical fruits used in juice production are passion fruit and mango. They are especially liked due to their intense aromas. Aroma and flavor are results of many constituents that are present in different concentrations, which are very sensitive to changes during thermal treatment used in the juice production. This work aimed at developing the sensory profile and evaluating the changes that may occur during the passion fruit juice processing. Three pass (more) ion fruit juices were analyzed: the raw material (pulp), which was pasteurized, kept in tambour and frozen; the ready-to-drink (formulated with sugar and water); and the pasteurized at 98 ºC, 30s. The sensory profile was composed of 13 attributes The quantitative descriptive analysis design comprised two factors, i.e. type of juice and panelists. The results were also analyzed using principal components analysis. Significant differences were found among the three juices except for the attribute passion fruit aroma and sweet aroma. the artificial aroma, cooked aroma, fermented aroma and fermented flavor were significantly higher (p

18

?-carotene biotransformation to obtain aroma compounds/ Biotransformação de ?-caroteno para obtenção de compostos de aroma  

Abstract in portuguese Carotenoides são importantes constituintes de alimentos por sua coloração e por seus produtos de degradação gerarem compostos voláteis em alimentos. Compostos de aromas derivados de carotenoides estão distribuídos na natureza, constituem precursores de aromas importantes em alimentos como frutas e em flores. Apresentam alto potencial aromático e, por isso, são de grande interesse para as indústrias de aromas e fragrâncias. Neste trabalho, mais de 300 microrgan (more) ismos foram selecionados pelo método da placa, de acordo com sua capacidade de degradar carotenoides presentes no meio de cultura. Cerca de 80 linhagens apresentaram capacidade de produção de aromas e 7 cepas apresentaram descritores e intensidades de aromas de interesse, segundo um painel não treinado de provadores, sendo selecionadas e submetidas à fermentação submersa para produção de compostos aromas derivados de ?-caroteno. ?-Ionona foi o principal produto obtido da degradação de ?-caroteno, encontrado em maiores concentrações nas linhagens CS1 (34,0 mg.L-1) e CF9 (42,4 mg.L-1) em 72 e 24 horas de fermentação nos meios de cultura sem e com pré-inóculo, respectivamente. Os compostos ?-damascona e pseudoionona foram encontrados em baixas concentrações, 1,1,6-trimetil-1,2,3,4-tetraidronaftaleno (TTN) foi tentativamente identificado e apocarotenoides, provavelmente obtidos da clivagem da parte central do carotenoide, foram detectados. Abstract in english Carotenoids are important constituents of food due to their color and because their degradation products generate important volatile compounds in foods. Aroma compounds derived from carotenoids are widely distributed in nature, and they are precursors of many important aromas in foods such as fruits and in flowers as well. They present high aromatic potential and are therefore of great interest to the industries of aromas and fragrances. In this study, more than 300 previ (more) ously isolated microorganisms with potential for biotransformation of ?-carotene present in the culture medium were selected using the plate method; about 80 strains presented capacity to produce aroma compounds and 7 strains were selected by an untrained panel of tasters to generate aroma compounds. The ?-ionone was the main compound produced by CS1 (34.0 mg.L-1) and CF9 (42.4 mg.L-1) microorganisms at 72 and 24 hours of fermentation, cultured with and without pre-inoculation, respectively. The ?-damascone and pseudoionone were found in low concentrations, 1,1,6-trimethyl-1,2,3,4-tetrahydronaphthalen (TTN) was tentatively identified and other compounds such as apocarotenoids, apparently obtained from the cleavage of the central part of the carotenoid, were detected.

19

Retenção de aroma na secagem em atmosferas normal e modificada: desenvolvimento do sistema de estudo/ Aroma retention in drying with normal and modified atmosphere: development of a study system  

Abstract in portuguese Na secagem de determinados alimentos, como frutas, juntamente com a água há também a evaporação de outras substâncias voláteis presentes em quantidades menores. Por isso, torna-se interessante considerar nos estudos de secagem a evaporação, além da água, desses outros componentes voláteis. A modificação da atmosfera tem sido utilizada em armazenamento, principalmente de vegetais, mas pode também ser estendida à secagem, pois pode influenciar a perda de vol (more) áteis responsáveis pelas características sensoriais do produto final. No presente trabalho, é apresentado um sistema de secagem previamente desenvolvido, no qual a atmosfera de secagem pode ser modificada pela adição de gases ou líquidos. Desenvolveu-se um sistema-modelo a partir da composição química básica do abacaxi e da adição de outros compostos, contendo um dos principais componentes do aroma desta fruta (hexanoato de etila). Além disso, também foi desenvolvida a metodologia analítica de determinação do aroma no sistema-modelo e no abacaxi, a partir dos estudos de extração de aromas e de análise cromatográfica gasosa. O aroma presente no sistema-modelo foi extraído em hexano e os componentes voláteis do aroma do abacaxi foram extraídos em éter etílico Abstract in english In the drying of some foods such as fruits, besides water there is also the evaporation of other volatile substances present in lesser amounts. Therefore, it is interesting to consider the evaporation of volatile components other than water in drying studies. The modification of atmosphere has been used for storage only, especially for vegetables, but it can be extended to drying since it can influence the loss of volatile components responsible for the sensorial characte (more) ristics of the final product. In the present study, a drying system previously developed, in which the drying atmosphere can be modified by the addition of gases or liquids, was presented. A model-system was developed from the basic chemical composition of pineapple and the addition of other compounds containing one of the main aroma components (ethyl hexanoate). An analytical methodology for determing the aroma components present in the model-system and in the pineapple was developed from the studies of aroma extraction and gas chromatography. The aroma present in the model-system was extracted with hexane, and the volatile aroma components of the pineapple were extracted with ethylic ether

20

Identification of characteristic aroma-active compounds in steamed mangrove crab (Scylla serrata)  

Mangrove crab (Scylla serrata) has delicate texture and flavor, high economic value, and is relatively easy to grow. With its total production reaching 177 million kg in 2008, mangrove crab has become one of the most important marine commercial crustaceans in China. The objective of this study was to evaluate the potent aroma-active compounds in steamed mangrove crab. Odorants of steamed crabmeat extracted by simultaneous steam distillation?solvent extraction were investigated by MS hyphenated to the GC?Olfactometry system with two olfactometric methods: detection frequency method and aroma extract dilution analysis. A total of 53 compounds were identified in steamed mangrove crab meat. 38 aroma-active components were further detected and 31 identified. The following 5 were the most import...

 
 
 
 
21

Evaluation of pervaporation process of kiwifruit juice by SPME-GC/Ion Trap Mass Spectrometry  

The processing of kiwifruit for obtaining products with a higher sensory quality, to be used in the food industry, is associated with the use of techniques which can limit the physical and chemical losses of aroma compounds. Pervaporation (PV) represents an alternative to the techniques based on distillation/evaporation or partial condensation to concentrate the aroma compounds preserving the molecule integrity (mild operational conditions used), having a high selectivity towards the organic volatile compounds, and respecting also the environment. The most representative volatile compounds of the kiwifruit aroma was chosen for evaluating the pervaporation process. SPME GC/ion trap mass spectrometry method was exploited to determine the amounts of these compounds. The approach was based on ...

22

Effects of fermentation temperature on the formation of aroma components in awamori mash. Awamori moromi no koki ni oyobosu hakko ondo no eikyo  

All materials for awamori are malt and the fermentation temperature of awamori mash is controlled at 25-30 centigrade, but the concentration of iso-butyl alcohol of the obtained product is higher than that of shochu. In this report, aiming at improvement of aroma composition of awamori, a study was made on synthetic media containing, as a nitrogen source, ammonium sulfate, L-valine and L-leucine, etc., and generation of aroma when culture temperature of awamori mash was changed. As a result, such information was obtained that, when awamori yeast was fermented at a low temperature (15 centigrade), the concentration of iso-butyl alcohol decreased considerably, thereby by producing low temperature mash, the concentration of iso-butyl alcohol of awamori could be controlled and this could be useful for improving its aroma composition. 14 refs., 2 figs., 1 tab.

23

Effects of Production Locations and Plucking Intervals on Clonal Tea Fatty Acids Levels in the Kenya Higlands  

Tea leaves contain unsaturated fatty acids which are precursors of aroma compounds. Despite uniform plucking practices in Kenya, plain black tea quality varies with locations. Variations in tea aroma and/or precursors with production area have not been established in a single cultivar under same agronomic input at different locations. Trials were conducted in five locations using clone BBK 35, harvested at varying intervals. The fatty acids varied (P ? 0.05) with locations and increased (P ? 0.05) with long plucking intervals, demonstrating leaf of same standard plucked at varying intervals contains different levels of fatty acids even in one location. The different increase rates in various locations might be in part the reason of the differences in aroma of black tea from different locations even when agronomic inputs are similar. Results demonstrate that harvesting at shorter intervals and developing region-specific plucking policies may improve tea quality.   

24

Impact of different malolactic fermentation inoculation scenarios on Riesling wine aroma  

During malolactic fermentation (MLF), lactic acid bacteria influence wine aroma and flavour by the production of volatile metabolites and the modification of aroma compounds derived from grapes and yeasts. The present study investigated the impact of different MLF inoculation strategies with two different Oenococcus oeni strains on cool climate Riesling wines and the volatile wine aroma profile. Four different timings were chosen for inoculation with bacteria to conduct MLF in a Riesling must/wine with a high acidity (pH 2.9?3.1). Treatments with simultaneous inoculation showed a reduced total fermentation time (alcoholic and malolactic) compared to the sequential inoculations. No negative impact of simultaneous alcoholic and malolactic fermentation on fermentation success and on the final...

25

Irradiation and fumigation effects on flavor, aroma and composition of grapefruit products  

Effects were evaluated on grapefruit treated to meet quarantine restrictions against Caribbean fruit fly infestation. Differences were found in flavor of fresh sections, fresh juice, and aroma of peel oil when obtained from fruit irradiated with x-rays, as compared with products from nonirradiated fruit. Flavor differences were found in all pasteurized juices from fruit irradiated at 50-60 krad. Vitamin C levels were significantly lower in juice from most irradiated fruit. Flavor differences were found in fresh and pasteurized juice from fruit treated with methyl bromide, and in pasteurized juice from fruit treated with ethylene dibromide. Aroma differences were found in peel oil from fruit treated with phosphine.

26

Climate change associated effects on grape and wine quality and production  

Climate change is exerting an increasingly profound influence on vine phenology and grape composition, and ultimately affects vinifications, wine microbiology and chemistry, and sensory aspects. Among the most important climate change-related effects are advanced harvest times and temperatures, increased grape sugar concentrations that lead to high wine alcohol levels, lower acidities and modification of varietal aroma compounds. Under extremely hot temperatures, which are already being experienced in some regions, vine metabolism may be inhibited leading to reduced metabolite accumulations, which may affect wine aroma and color. Musts with high sugar concentrations cause a stress response in yeast, which leads to increased formation of fermentation co-products, such as acetic acid. If not...

27

Comparative metabolic profiling to investigate the contribution of O. oeni MLF starter cultures to red wine composition  

In this research work we investigated changes in volatile aroma composition associated with four commercial Oenococcus oeni malolactic fermentation (MLF) starter cultures in South African Shiraz and Pinotage red wines. A control wine in which MLF was suppressed was included. The MLF progress was monitored by use of infrared spectroscopy. Gas chromatographic analysis and capillary electrophoresis were used to evaluate the volatile aroma composition and organic acid profiles, respectively. Significant strain-specific variations were observed in the degradation of citric acid and production of lactic acid during MLF. Subsequently, compounds directly and indirectly resulting from citric acid metabolism, namely diacetyl, acetic acid, acetoin, and ethyl lactate, were also affected depending on t...

28

Characterization of woody odorant contributors in copaiba oil (Copaifera multijuga Hayne)  

Abstract in portuguese Copaifera multijuga Hayne é uma das espécies do gênero Copaifera da qual se extrai o óleo de copaíba. Além do uso como antiinflamatório e anti-séptico, o óleo de copaíba é utilizado na indústria de fragrâncias como fixador para perfumes, cosméticos e sabões. A fim de identificar as substâncias ativas no aroma do óleo de C. multijuga, CG-O-EM utilizando AEDA foi aplicada após a quantificação dos compostos por CG-DIC. Os resultados obtidos apontaram para (more) delta-cadineno (1,9%, FD 64), delta-cadinol (0,9%, FD 128), óxido de cariofileno (0,2%, FD 64), (Z)-alfa-santalol (0,2%, FD 128), alfa-cadinol (0,1%, FD 128) e tau-muurolol (0,1%, FD 128) como as substâncias de odor mais ativo no aroma deste óleo de copaíba. Quanto à contribuição aromática dos enanciômeros do delta-cadineno analisada por CG-EM-O-quiral, somente o enanciômero (+)-delta-cadineno foi encontrado no óleo e apresentou aroma adocicado, verde e refrescante. Abstract in english Copaifera multijuga Hayne is one of the Copaifera species from which copaiba oil is extracted. Employed in the composition of anti-inflammatory and antiseptic products used in phytotherapy, it is also used by the fragrance industry as a fixative in perfumes, cosmetics and in products such as soaps. To identify the active aroma compounds in C. multijuga oil bouquet, GC-O-MS using AEDA (Aroma Extract Dilution Analysis) was used after the quantification of the components by (more) GC-FID. The results obtained pointed to minor compounds such as delta-cadinene (1.9%, FD 64), delta-cadinol (0.9%, FD 128), (Z)-alpha-santalol (0.2%, FD 128) caryophyllene oxide (0.2%, FD 64), alpha-cadinol (0.1%, FD 128) and tau-muurolol (0.1%, FD 128) as the most intense compounds in the odor of the copaiba oil studied. Chiral GC-O-MS showed (+)-delta-cadinene as the only enantiomer present in the oil, with a sweet, green and refreshing aroma.

29

Crescimento do morangueiro: influência da cultivar e da posição da planta no canteiro/ Strawberry growth: effect of cultivar and plant position in the bed  

Abstract in portuguese O objetivo deste trabalho foi avaliar o crescimento de cultivares de morangueiro em sistema de cultivo orgânico, observando a influência da posição da planta no canteiro sobre a produção acumulada e a partição de massa seca entre os órgãos aéreos das plantas. O experimento foi realizado na Embrapa Clima Temperado, Estação Experimental Cascata, Pelotas, RS. Os tratamentos constaram da combinação de dois fatores experimentais: cultivar ('Albion', 'Aromas', 'C (more) amarosa' e 'Camino Real') e a posição das plantas no canteiro (Central e Bordadura). O delineamento experimental adotado foi o de blocos completos casualizados com parcelas divididas e quatro repetições. A cultivar 'Camarosa' apresentou maior produção de massa seca dos órgãos aéreos das plantas (62,3; 27,5 e 88,0g planta-1 para folha, coroa e frutos, respectivamente) e, juntamente com a 'Aromas', maior produtividade (64,2 e 59,1Mg ha-1, respectivamente). A cultivar 'Aromas' apresentou a maior contribuição proporcional dos frutos para a composição do total de massa seca da planta (60,6%) e o maior índice de colheita (88%). A posição das plantas não influenciou o crescimento e a produtividade, indicando ausência de efeito de bordadura para as cultivares 'Albion', 'Aromas', 'Camarosa' e 'Camino Real'. Abstract in english The aim of this research was to evaluate the growth of strawberry cultivars growing in organic crop system observing the influence of plant position in the bed on accumulated dry matter production and its partitioning among the aboveground plant organs. The experiment was conducted in Embrapa Clima Temperado, Estação Experimental Cascata, Pelotas, RS. The treatments were compose by the combination of two experimental factors: cultivar ('Aromas', 'Albion', 'Camarosa' and (more) 'Camino Real') and plant position in the bed (Central and Border). The experimental design used was randomized blocks with split-plots and four replications. 'Camarosa' cultivar presented highest dry mass production of aboveground organs (62.3; 27.5 and 88.0g plant-1 for leaves, crown and fruits, respectively), and together 'Aromas', highest yield (64.2 and 59.1Mg ha-1, respectively). 'Aromas' cultivar presented highest fruit dry mass contribution for the total aboveground dry mass production (60.6%) and the highest harvest index (88%). The plant position in the bed did not influence the growth and yield of the plants, which indicate no border effect for the 'Albion', 'Aromas', 'Camarosa' and 'Camino Real' strawberry cultivars.

30

Tea in promotion of human health  

Because of its special aroma, taste and low cost, next to water, tea has been the most common beverage consumed by humans.Tea leaves are primarily manufactured as black, green, or oolong, with black tea representing approximately 80% of tea products consumed worldwide. Even though health beneficial ...

31

Application of E-nose technology for ultra-high temperature processed partly skimmed milk production batches monitoring  

In our work we present a case study of the capability of one electronic nose (P.E.N. 2 sensor array by Airsense Analytics, Germany) in discriminating different qualities of milk samples by sensing their aroma. All the analyzed milk samples, belonging both to different production batches and to diffe...

32

Production of Sulfur Flavors by Ten Strains of Geotrichum candidum  

Ten strains of Geotrichum candidum were studied on a liquid cheese model medium for the production of sulfur compounds which contribute to the aroma of cheeses. The volatile components produced by each cultured strain were extracted by dynamic headspace extractions, separated and quantified by gas c...

33

CLONING AND FUNCTIONAL EXPRESSION OF AN (E,E)-ALPHA-FARNESENE SYNTHASE CDNA FROM APPLE FRUIT  

Increased production of terpenes and many other aroma-related volatiles occurs with the onset of ripening in apple fruit. The gaseous plant hormone ethylene plays a key role in the induction of volatile synthesis, but the mechanism is not yet understood. Using a degenerate primer based on a short co...

34

CLONING AND FUNCTIONAL EXPRESSION OF AN (E)-NEROLIDOL SYNTHASE CDNA FROM PEEL TISSUE OF APPLE FRUIT  

Increased production of terpenes and many other aroma-related volatiles occurs with the onset of ripening in apple fruit. The gaseous plant hormone ethylene plays a key role in the induction of volatile synthesis, but the mechanism is not yet understood. Using a degenerate primer based on a short co...

35

Enhancing safety and aroma appealing of fresh-cut fruits and vegetables using the antimicrobial and aromatic power of essential oils.  

Microbial and aroma attributes are within the most decisive factors limiting safety and sensory appealing of fresh-cut fruits and vegetables. Alternatively, several plant essential oils (EOs) are constituted of several volatile active compounds and most of them present antimicrobial potential and had different aroma profile. Considering these premises, this hypothesis article states that safety and aroma appealing of fresh-cut produce could be improved with EO treatment. EOs could prevent fresh-cut fruit decay; however, their volatile constituents could be sorbed by the produce, and according to the aroma notes of the antimicrobial oil, sensorial appealing of odor, and flavor of the treated produce might be affected positively or negatively. Specifically, garlic oil is a natural antimicrobial constituted by sulfur compounds, which are responsible for its odor and antimicrobial properties. Besides, fresh-cut tomato is a highly perishable product that needs antimicrobial agents to preserve its quality and safety for a longer period of time. From the sensorial point of view, aroma combination of garlic and tomato is a common seasoning practice in Europe and America and well accepted by consumers. Once the right combination of flavors between the EOs and the fresh-cut produce has been selected, safety and quality of the treated fruit could be improved by adding antimicrobial protection and extra aroma. Therefore, other combinations between EOs and fresh-cut produce are discussed. This approximation could reinforce the trends of natural food preservation, accomplishing the demands of the increasing sector of consumers demanding tasty and convenient fresh-cut produce, containing only natural ingredients. PMID:19895494

36

Análise sensorial de músculo de mapará com e sem tratamento osmótico/ Sensorial evaluation of mapará muscle with and without osmotic treatment  

Abstract in portuguese O objetivo deste trabalho foi avaliar sensorialmente o mapará in natura e com pré-tratamento osmótico antes da secagem. Para o teste de aceitabilidade do bolinho de músculo de mapará, foram utilizados peixes in natura e desidratados osmoticamente, nas melhores condições de processo, em soluções de NaCl, NaCl + sacarose e em solução de NaCl + xarope de milho e secos. Foram utilizados 25 provadores não treinados, de ambos os sexos, com idade variando de 20 a 60 (more) anos. Os atributos sensoriais avaliados foram aparência, aroma, sabor, textura e impressão global. O aroma e a textura das amostras com e sem pré-tratamento osmótico foram os atributos que obtiveram maior aceitação por parte dos consumidores. Pôde-se concluir que as amostras tratadas com soluções osmóticas, com exceção das tratadas com solução de NaCl + xarope de milho, proporcionaram produtos com textura, sabor e aroma mais agradáveis. Abstract in english The objective of this work was the sensorial evaluation of mapará meat, in natura and without osmotic pre-treatment before drying. For the acceptability test of the mapará fish muscle bisquit, the in natura fish samples were used and dried under optimum osmotic dehydration conditions, in solutions of NaCl, NaCl + sucrose and in solution of NaCl + corn syrup solution before drying. 25 not trained testers were used, of both sex, ages ranging from 20 to 60 years. The evalu (more) ated sensorial attributes of the samples were appearance, aroma, flavor, texture and overall impression. The aroma and texture of the samples with and without osmotic pre-treatment were the ones most widely accepted by the consumers. It is concluded that the samples treated with osmotic solutions, with the exception of those processed with NaCl + corn syrup solution, provided products with better texture, flavor and a more pleasant aroma.

37

Analysis of glycosidically bound aroma precursors in tea leaves. 3. Change in the glycoside content of tea leaves during the oolong tea manufacturing process.  

A direct qualitative and quantitative determination of the glycosides of tea aroma compounds at the four stages of the oolong tea manufacturing process (plucking, solar withering, indoor withering, and oolong tea product) was carried out by a capillary gas chromatographic-mass spectrometric analysis after trifluoroacetyl derivatization of the glycosidic fractions. Sixteen glucosides and primeverosides were identified and quantified in cv. Chin-shin-oolong and cv. Chinhsuan-oolong. A comparison of the glycosides in dried fresh leaves between the two cultivars showed significant differences. During the manufacturing process, the amounts of most of these glycosides increased from the solar-withering stage, reaching the highest level at the final stage of oolong tea production. It was noted that no glycoside decreased in its content during the manufacturing process, this being quite different from the manufacture of black tea. In addition, the contents of these alcoholic aroma compounds in the free aroma concentrate from each cultivar remained almost unchanged or slightly decreased, and they constituted only about 12 and 17% in amount of the whole oolong tea aroma compounds. However, jasmine lactone and indole were markedly higher in the final oolong tea products. PMID:11714333

38

Volatile profile and physical, chemical, and biochemical changes in fresh cut watermelon during storage/ Perfil volátil e alterações físicas, químicas e bioquímicas na melancia minimamente processada durante o armazenamento  

Abstract in portuguese Existe pouca informação a respeito do aroma de melancia minimamente processada e das alterações metabólicas que ocorrem com o processamento mínimo. Sabendo-se que há estreita relação entre aroma característico, textura e qualidade torna-se necessário o conhecimento a respeito das alterações do perfil volátil e textura deste produto, que é intensamente comercializado nas redes de supermercados do Brasil. Diante disso, o objetivo deste trabalho foi analisar o (more) perfil volátil utilizando a técnica de microextração em fase sólida (SPME) e as modificações relacionadas à textura de melancia minimamente processada armazenada a 5 °C, por dez dias. A cromatografia associada com análise sensorial ('sniffing') permitiu concluir que os álcoois e aldeídos com nove carbonos (C9) são os principais compostos responsáveis pelo sabor e aroma de melancia minimamente processada armazenada a 5 ± 1 °C/90 ± 5% UR, durante dez dias e que a intensidade desse aroma diminui com o armazenamento, porém, sem comprometer a qualidade final do produto. Observou-se que o teor de líquido drenado, pectina solúvel e perda de massa aumentaram ao longo do armazenamento com concomitante diminuição da firmeza. A atividade de pectinametilesterase permaneceu constante e a de poligalacturonase não foi detectada. Abstract in english Existing data about the aroma of fresh-cut watermelon and the metabolic changes that occur with minimal processing are scarce. Given the close relationship that exists between aroma, texture, and quality characteristics, it is necessary to investigate the changes in the volatile profile and texture of watermelon, a fruit extensively sold in supermarket chains throughout Brazil. The objective of this work was to analyze the volatile profile using solid phase microextractio (more) n (SPME) as well as texture changes in fresh-cut watermelon stored at 5 °C for ten days. Chromatography associated with sensory analysis (sniffing) led us to conclude that 9-carbon (C9) alcohols and aldehydes are the major responsible for the flavor and aroma of minimally processed watermelon stored at 5 ± 1 °C/90 ± 5% RH for ten days, and also that the aroma diminishes in intensity with storage, but it does not affect the final quality of the product. It was noted that the amount of drained liquid, soluble pectin, and weight loss increased during storage concurrently with a reduction in firmness and a structural breakdown of the cells. Pectin methyl esterase activity remained constant and polygalacturonase activity was not detected.

39

Bioconversion of lutein using a microbial mixture--maximizing the production of tobacco aroma compounds by manipulation of culture medium.  

The generation of aroma compounds by carotenoid cleavage in the 9-10 position was studied, due to the importance of these compounds in the flavor and fragrance industry. The bioconversion of the carotenoid lutein to C(13) norisoprenoids utilizing a microbial mixture composed of Trichosporon asahii and Paenibacillus amylolyticus was carried out by a fermentation process. Applying an experimental design methodology, the effects of nutritional factors on the production of aroma compounds present in the tobacco profile were studied. After an assessment of the significance of each nutritional factor, the levels of the variables yielding the maximum response were calculated. Glucose, tryptone, and yeast extract exerted a strong negative effect over the objective function, with glucose being the strongest. Lutein possessed a positive effect over the tobacco aroma production, while sodium chloride and trace elements showed no influence over the process. The yield attained after culture medium manipulation was almost ten-fold higher, compared with the base medium; and the aroma mixture was characterized as: 7,8-dihydro-beta-ionol (95.2%), 7,8-dihydro-beta-ionone (3.7%), and beta-ionone (1.1%). PMID:15660215

40

Impact of different malolactic fermentation inoculation scenarios on Riesling wine aroma.  

During malolactic fermentation (MLF), lactic acid bacteria influence wine aroma and flavour by the production of volatile metabolites and the modification of aroma compounds derived from grapes and yeasts. The present study investigated the impact of different MLF inoculation strategies with two different Oenococcus oeni strains on cool climate Riesling wines and the volatile wine aroma profile. Four different timings were chosen for inoculation with bacteria to conduct MLF in a Riesling must/wine with a high acidity (pH 2.9-3.1). Treatments with simultaneous inoculation showed a reduced total fermentation time (alcoholic and malolactic) compared to the sequential inoculations. No negative impact of simultaneous alcoholic and malolactic fermentation on fermentation success and on the final wine volatile aroma composition was observed. Compared to sequential inoculation, wines with co-inoculation tended to have higher concentrations of ethyl and acetate esters, including acetic acid phenylethylester, acetic acid 3-methylbutylester, butyric acid ethylester, lactic acid ethylester and succinic acid diethylester. Results of this study provide some alternatives to diversify the number of wine styles by safely conducting MLF in low-pH, cool-climate white musts with potential high alcohol content. PMID:22805835

 
 
 
 
41

Hot and cold water infusion aroma profiles of Hibiscus sabdariffa: fresh compared with dried.  

Calyxes from the Roselle plant (Hibiscus sabdariffa L.) were used to prepare cold (22 °C for 4 h) and hot (98 °C for 16 min) infusions/teas from both fresh and dried forms. Aroma volatiles were extracted using static headspace SPME and analyzed using GC-MS and GC-O with 2 different columns (DB-5 and DB-Wax). Totals of 28, 25, 17, and 16 volatiles were identified using GC-MS in the dried hot extract (DHE), dried cold extract (DCE), fresh hot extract (FHE), and fresh cold extract (FCE) samples, respectively. In terms of total GC-MS peak areas DHE ? DCE > FHE ? FCE. Nonanal, decanal, octanal, and 1-octen-3-ol were among the major volatiles in all 4 beverage types. Thirteen volatiles were common to all 4 teas. Furfural and 5-methyl furfural were detected only in dried hibiscus beverages whereas linalool and 2-ethyl-1-hexanol were detected only in beverages from fresh hibiscus. In terms of aroma active volatiles, 17, 16, 13, and 10 aroma active volatiles were detected for DHE, DCE, FHE, and FCE samples, respectively. The most intense aroma volatiles were 1-octen-3-one and nonanal with a group of 4 aldehydes and 3 ketones common to all samples. Dried samples contained dramatically higher levels of lipid oxidation products such as hexanal, nonanal, and decanal. In fresh hibiscus extracts, linalool (floral, citrus) and octanal (lemon, citrus) were among the highest intensity aroma compounds but linalool was not detected in any of the dried hibiscus extracts. PRACTICAL APPLICATION: Hibiscus teas/infusions are one of the highest volume specialty botanical products in international commerce. The beverage is consumed for both sensory pleasure and health attributes and is prepared a number of ways throughout the world. Although color and taste attributes have been examined, little information is known about its aroma volatiles and no other study has compared extractions from both fresh and dried as well as extraction temperature differences. This is also, apparently, the first study to identify the aroma active volatiles in hibiscus beverages using GC-olfactometry. Manufacturers and consumers will now have a better understanding of why hibiscus teas prepared in different ways from either fresh or dried forms have a different flavor quality and intensity. PMID:21535737

42

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

Abstract in portuguese 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 (more) 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. Abstract in english 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 acceptan (more) ce 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

43

Volatile characterization by multivariate optimization of headspace-solid phase microextraction and sensorial evaluation of chardonnay base wines  

Abstract in portuguese Pouco é conhecido sobre o aroma dos vinhos produzidos na região sul do Brasil, que é responsável por 90% da produção brasileira de vinho. Um método baseado na microextração em fase sólida no modo "headspace" (HS-SPME) foi desenvolvido para a extração de compostos voláteis e semivoláteis relacionados ao aroma de vinhos base, de cinco diferentes vinícolas do estado do Rio Grande do Sul (Brasil). A relação entre a composição volátil, qualidade aromática (more) e avaliação sensorial dos vinhos Chardonnay foi investigada neste estudo. As condições otimizadas do método de HS-SPME foram: utilização da fibra DVB-CAR-PDMS, 1 mL de amostra, 30% de NaCl, 45 min de extração a 55 ºC, sem o uso de diluição e agitação da amostra. Dezoito compostos foram identificados e catorze foram tentativamente identificados. Os ésteres foram os compostos majoritários (56%) e os outros compostos minoritários pertencem à classe dos álcoois e ácidos. Os vinhos do Vale dos Vinhedos e de Pinto Bandeira apresentaram a mais alta pontuação em relação aos parâmetros sensorais avaliados. Estes vinhos foram caracterizados por altas concentrações de ésteres etílicos, o que contribui para o aroma frutado dos vinhos Abstract in english Very little is known about the aroma of wines produced in the South part of Brazil, a region that is responsible for 90% of the Brazilian wine production. A headspace solid phase micro extraction (HS-SPME) method was developed for the extraction of volatile and semivolatile compounds related to the aroma of base wines of five different wineries of the state of Rio Grande do Sul (Brazil). The relationships among volatile composition, aroma quality and sensory evaluation of (more) Chardonnay base wines were performed in this study. Optimum conditions for HS-SPME included use of DVB?CAR?PDMS coating, wine samples without further dilution, no stirring, sample volume of 1 mL, 30% of NaCl, extraction time and temperature of 45 min and 55 ºC, respectively. Eighteen compounds were identified and fourteen were tentatively identified in the samples. The majority (56%) of them was esters and other minor components were alcohols and acids. The sensory analysis of Vale dos Vinhedos and Pinto Bandeira samples showed the highest quality scores, characterized by higher concentrations of ethyl esters, which contributes to the fruity aroma of these wines.

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Flavor retention of peppermint (Mentha piperita L.) essential oil spray-dried in modified starches during encapsulation and storage  

The effect of different commercial modified food starch carrier materials on the flavor retention of the essential oil (EO) of peppermint (Mentha piperita L.) during spray drying and storage was evaluated. The obtained results revealed that the emulsification and encapsulation efficiencies of peppermint EO were higher for all n-octenyl succinic anhydride (OSAN)-modified starches as compared to those of hydrolyzed starches (dextrins). The compositions of pure, emulsified, and encapsulated peppermint EOs in different matrices were quite similar; however, some changes in the percentages of some individual compounds were observed. Larger differences in the compositions of surface oils from various encapsulation products were obtained. Flavor components were released at different rates by each of the encapsulated products. The aroma binding capacity of different modified starch matrices to lock EO droplets depends on the water activity, and the leakage of aromas from encapsulated powder products during storage increased with increasing water activity.

45

Caracterización anatómica del leño y evolución del crecimiento en ejemplares de Acacia aroma y Acacia furcatispina en la Región Chaqueña, Argentina/ Wood anatomical description and growth in individuals of Acacia aroma and Acacia furcatispina in Chaco region, Argentina  

Abstract in spanish La madera de Acacia aroma y Acacia furcatispina se emplea para usos de escaso valor como postes, mangos de herramientas o combustible. Los objetivos de este trabajo fueron estudiar los caracteres anatómicos del leño de ambas especies y analizar el crecimiento de ejemplares aislados con la finalidad de determinar su potencialidad para usos de mayor valor. Se determinó que la madera de estas especies es dura, pesada y de porosidad difusa con tendencia a semicircular. Aca (more) cia furcatispina posee un leño con mayor porcentaje de elementos lignificados, mejores cualidades estéticas y mejor estado fitosanitario que el de A. aroma. Los defectos más frecuentes en estas especies fueron la formación de leño decolorado y pudriciones en la zona del duramen por ataque de hongos, asociados a la presencia de cicatrices de fuego. El espesor promedio de los anillos de crecimiento fue 2,1 mm (DE = 0,47 mm) en A. aroma y 1,9 mm, (DE = 0,74 mm) en A. furcatispina. Las curvas de incremento medio anual e incremento corriente anual del diámetro en A. aroma se interceptan a los 24 años mientras que las de A. furcatispina lo hacen a la edad de 10 años. Los resultados indicaron que A. furcatispina es una especie interesante para manejar en plantaciones debido a las cualidades de su madera, aunque permitiría obtener escuadrías menores. Su madera podría destinarse a usos particulares como parquets, tallas artísticas, entre otros. Acacia aroma es una especie apropiada para manejar con el objetivo de producción de leña debido a la capacidad de producir fustes y ramas de mayor diámetro y a que su estado fitosanitario limita su empleo para otros usos de mayor valor. Abstract in english The wood of Acacia aroma and Acacia furcatispina is employed for uses of little value such us posts, tools and firewood. The objectives of this work were to study anatomical characters of wood and to analyze the growth of isolated individuals with the purpose of determining their potential for uses of greater value. We determined that these species have high density and heavy wood, with diffuse porosity and tendency to semicircular. The wood of Acacia furcatispina has gre (more) ater percentage of ligneous elements, better aesthetics qualities and health state than A. aroma. The most frequent defects in these species are rots within heartwood due to fungi attack, and discolorated wood formation, both related to fire scars. The mean width of the growth rings was 2.1 mm (DE = 0.47 mm) in A. aroma and 1.9 mm (DE = 0.74 mm) in A. furcatispina. In A. aroma, the curve of mean annual increment (IMA) intercepted the curve of current annual increment (ICA) for diameter at an age of 24 years, while in A. furcatispina it happened at 10 years. The results show that A. furcatispina is an interesting species to manage in plantations due to its wood qualities, although it would only allow small sized timber. This wood could be allocated for others uses such us parquets and artistic sculpture. Acacia aroma is a species suitable to manage for firewood production due to its capacity to produce greater diameter boles and branches, and to frequent wood decay that reduces its use for others more valuables uses.

46

Freeze Concentration of Black Currant Juice  

Freeze concentration is a method used to remove pure water from juice, wine, or beer by means of crystallization. The closed and fully filled liquid system completely preserves the quality of the fresh juice while operating at subzero Celsius temperatures. The aroma (including the volatile aroma that characterizes freshly squeezed juice), color, and flavor remain in the concentrated juice. Another advantage of this proven technology is the low operating temperature used that allows concentration of heat sensitive products such as black currant juice. The quality of freeze concentrated products cannot be achieved by any other technology. The solid concentration of the freeze concentrated black currant juice was increased to 39 Degrees Brix (Bx). It will be shown that the quality of this jui...

47

Volatile ester-synthesising capacity throughout on-tree maturation of 'Golden Reinders' apples  

Volatile compounds emitted by apple (Malusxdomestica Borkh.) fruit change during maturation and ripening, and hence maturity stage at harvest is a key factor determining fruit aroma. In this work, production of aroma volatile compounds and some related enzyme activities were monitored weekly in 'Golden Reinders' apples during 7 weeks prior to commercial harvest. Three maturity stages (immature, mature unripe and ripe) could be defined by the variables studied. Esters were quantitatively prominent among the compounds identified in the volatile fraction, and in most cases their production was higher at later stages of fruit maturation. Hexyl acetate, hexyl propanoate and hexyl 2-methylbutanoate, together with ethyl 2-methylbutanoate, 2-methylbutyl acetate and butyl 2-methylbutanoate, were fo...

48

Expression of genes associated with aroma formation derived from the fatty acid pathway during peach fruit ripening.  

Changes in characteristic aroma volatiles, levels of fatty acids as aroma precursors, and expression patterns of related genes, including lipoxygenase (LOX), hydroperoxide lyase (HPL), alcohol dehydrogenase (ADH), alcohol acyltransferase (AAT), and fatty acid desaturase (FAD), were studied in peach ( Prunus persica L. Batsch., cv. Yulu) fruit during postharvest ripening at 20 degrees C. Concentrations of n-hexanal, (E)-2-hexenal, (E)-2-hexenol, and (Z)-3-hexenol decreased, whereas the production of (Z)-3-hexenyl acetate, gamma-hexalactone, gamma-octalactone, gamma-decalactone, and delta-decalactone increased with fruit ripening. Lactones showed a clear pattern concomitant with the climacteric rise in ethylene production, with gamma-decalactone being the principal volatile compound at the late ripening stage. Of the LOX family genes, PpLOX2 and PpLOX3 had relatively high transcript levels initially followed by a decline with fruit ripening, while levels of PpLOX1 and PpLOX4 transcripts were upregulated by accumulated ethylene production. Expression of PpHPL1, PpADH1, PpADH2, and PpADH3 showed similar decreasing patterns during ripening. Expression levels of PpAAT1 showed a rapid increase during the first 2 days of postharvest ripening followed by a gradual decrease. Contents of polyunsaturated linoleic and linolenic acids increased, and saturated palmitic acid levels tended to decline as the fruit ripened. The increased levels of unsaturated fatty acids closely paralleled increasing expression of PpFAD1 and PpFAD2. The significance of gene expression changes in relation to aroma volatile production is discussed. PMID:20415420

49

True cooking aroma or artefact. {sup 15}N gives the answer; Veritable arome de cuisson ou artefact. {sup 15}N fournit la reponse  

In order to determine the respective contributions of the various nitrous precursor families in aroma preparations, the usually added amino acids were substituted with {sup 15}N isotope labelled homologous components. Results concerning isotope ratios for the volatile fraction nitrous components collected from poultry meat aromatic preparations, are presented. Terminal product labelling appears to allow for a better determination of the substrate and functional additive contributions. 4 figs., 6 refs.

50

Sensory and instrumental analysis of food aromas  

Food aromas are generally perceived as unitary aromas, i.e. fried potatoes smell like fried potatoes and roasted coffee smells like roasted coffee. Nonetheless, nearly all food aromas are produced by a multitude of volatile components that contribute to an extensive collection of aromas in various c...

51

Influência da torra sobre a aceitação da bebida café/ Sensory study of the roast type about acceptance of the coffee beverage  

Abstract in portuguese O café é um dos poucos produtos agrícolas valorizado com base em parâmetros qualitativos, em que quanto melhor for a qualidade maior será o preço obtido. Essa qualidade, contudo, é dependente de diversos fatores que se relacionam em todas as etapas da sua produção, desde a escolha da variedade ou de cultivar a ser plantada até o preparo da bebida. A torração é uma etapa muito importante para a qualidade do café, estando diretamente relacionada à aceitação (more) da bebida. O presente trabalho teve por objetivo avaliar a aceitação ou preferência das bebidas tipo mole, dura e rio de café submetidas a três diferentes tipos de torra (clara, expresso e escura). Foi realizado um teste de aceitação com 65 consumidores de café, utilizando-se uma escala hedônica de nove pontos, sendo avaliados separadamente a cor, o aroma, o sabor e a impressão global. Os resultados foram avaliados por meio do Mapa de Preferência Interno (MDPREF). As amostras de torra escura, independentemente do tipo de bebida, foram de maior preferência dos consumidores em relação aos atributos cor, aroma, sabor e impressão global. As de torra clara, rio/expresso e dura/expresso, de acordo com os consumidores, tiveram menor preferência quanto à cor. Para os atributos aroma, sabor e impressão global as amostras de torra clara e rio/expresso foram menos aceitas. Abstract in english The coffee is one of the few agricultural products that it is valued with base in qualitative parameters, in that as better the larger quality will be the obtained price. This quality, however, it is dependent of several factors that link in all the stages of the production of the coffee, from the choice of the variety or cultivars to be planted until the preparation of the beverage. The roasting is a very important stage for the quality of the coffee being directly relat (more) ed the acceptance of the beverage. The present work had for objective to evaluate the acceptance of the drink coffee of the type's soft, hard and "rio" was submitted to three different types of roast (light, express and dark). An acceptance test was accomplished with 65 consumers of coffee using a hedonic scale of nine points, being evaluated the color, the aroma, the flavor and the global impression. The results obtained were analyzed by Internal Preference Map (PREFMD). The samples of roast dark independent of the class were of the consumers larger preference in relation to the attributes color, aroma, flavor and overall. The samples of roast light, "rio"/express and hard/express, in agreement with the consumers they had smaller preference? as the color. For the attributes aroma, flavor and overall the samples of roast light and "rio"/express were less accept.

52

Desempenho produtivo de mudas nacionais e importadas de morangueiro/ Agronomic performance of national and imported strawberry plants  

Abstract in portuguese O objetivo deste trabalho foi avaliar o desempenho produtivo de mudas nacionais e importadas de morangueiro das cultivares Aromas e Camarosa, nas condições climáticas de Pelotas. O experimento foi realizado utilizando sistema de produção sob túnel, irrigação por gotejamento e adubação fornecida via água de irrigação. O transplantio das mudas foi realizado em junho de 2005, num espaçamento de 35 cm entre linhas e entre plantas. Utilizaram-se mudas de duas cul (more) tivares (Aromas e Camarosa) e de três procedências (Chile, Serra Gaúcha e região de Pelotas). Os tratamentos foram dispostos em delineamento de blocos ao acaso, em esquema fatorial com quatro repetições. As unidades experimentais foram constituídas por 20 plantas. Semanalmente, de agosto a dezembro, foram analisadas as variáveis número e massa fresca de frutos. A cv. Camarosa (569,6 g planta-1) foi mais produtiva do que a 'Aromas' (510,4 g planta-1). Independentemente da cultivar, as mudas importadas do Chile proporcionaram maior produção de frutos comerciais (724,5 g planta-1) e frutos de maior massa (15,5 g) do que as mudas produzidas na região de Pelotas (493,3 planta-1 e 12,6 g fruto-1) e na Serra Gaúcha (402,3 g planta-1 e 11,7 g fruto-1). Abstract in english The aim of this work was to compare the agronomic performance of national and imported strawberry plants, using Aromas and Camarosa cultivars at the climatic conditions of Rio Grande do Sul. The experiment was carried out in Pelotas, using tunnel system and fertirrigation. In June of 2005, the strawberry plants from three regions (Chile, Serra Gaúcha and Pelotas) and two cultivars (Aromas and Camarosa) were transplanted at the distance of 35 cm between lines and between (more) plants. The treatments were disposed according to a randomized complete block design and a factorial arrangement with four replications. The experimental units were composed by 20 plants. Weekly, from August to December, the variables fruit fresh weight and number of fruits produced in each experimental unit were studied. Camarosa cultivar (569,6 g plant-1) was more productive than Aromas (510,4 g plant-1). Independently of the cultivar, the imported plants from Chile showed greater production of commercial fruits (724,5 g plant-1) and fruits of bigger average weight (15,5 g) than those produced in Pelotas region (493,3 g plant-1 and 12,6 g fruit-1) and in Serra Gaúcha (402,3 g plant-1 and 11,7 g fruit-1).

53

Real-time sensing of roses' aroma using an odor sensor of quartz crystal resonaotors  

In order to detect plant aroma in a natural environment, we have investigated roses' aroma using an odor sensor of quartz crystal resonator (QCR).In present work, we describe experimental setup for real-time sensing of roses' aroma and feature extraction of roses' aroma sensed by QCR sensors. This method can distinguish as different aroma as human sense of smell judged for two kinds of roses. We measured one rose's aroma 3 times repeatedly in first day, second day and third day, respectively, and the result shows that rose aroma of first day is different from the ones of the other two days.   

54

The performance of pervaporative aroma recovery units: Process simulations  

Pervaporation is an emerging membrane-based separation technique which is very promising, for instance, for aroma recovery. Computer simulations of the behavior of large-scale pervaporation units for aroma recovery indicated that aroma concentrates can be produced by using this technique. For four of the five aroma compounds investigated, the degrees of recovery were high. The simulations showed that some process parameters, e.g., temperature, degree of aroma folding, and membrane material, strongly affect the performance of the process.

55

Gas Chromatography/Olfactometry and Electronic Nose Analyses of Retronasal Aroma of Espresso and Correlation with Sensory Evaluation by an Artificial Neural Network  

Abstract: To develop a method for evaluating and designing the retronasal aroma of espresso, sensory evaluation data was correlated with data obtained from gas chromatography/olfactometry (GC/O, CharmAnalysis ) and from an electronic nose system FOX4000 (E nose). The volatile compounds of various kinds of espresso (arabica coffee beans from 6 production countries: Brazil, Ethiopia, Guatemala, Colombia, Indonesia, and Tanzania; 3 roasting degrees for each country: L values, 18, 23, and 26) were collected with a retronasal aroma simulator (RAS) and examined by GC/O and E nose. In addition, sensory descriptive analysis using a 7 point scale for RAS effluent gas was performed by 5 trained flavorists using sensory descriptors selected based on the frequency in use and coefficient of correlation...

56

Quality evaluation of mixed brewed perries based on PCA and sensory evaluation  

In order to improve the sensory quality of Yali perry and choose fruits specially suitable for mixed fermentation with Yali pear, 11 kinds of fruits were selected and contrasted, including hawthorn, kiwifruit, Kyoho grape, Brown plum, Fuji apple, Nanguo pear, Dongzao jujube, Mopan persimmon, Korla pear, and Chi pear. These fruits were mixed separately with Yali pear, thus turning out 64 different types of mixed perries. The assessment on products was made based on the physiochemical indexes, aroma components via gas chromatography-mass spectrometry (GC-MS), and comparison between the qualities of the mixed perries via sensory evaluation and principal component analysis (PCA). Based on the PCA on the physiochemical indexes of 39 mixed perries and aroma components of 7 mixed perries, the mod...

57

Sensory acceptance tests of red beet (Beta vulgaris ssp. vulgaris L.), cv. Early Wonder, minimally processed and irradiated; Testes sensoriais de aceitacao da beterraba vermelha (Beta vulgaris ssp. vulgaris L.), cv. Early Wonder, minimamente processada e irradiada  

Red beet (Early Wonder) was cultivated in an experimental area of the Department of Fitotecnia at the Institute of Agronomy at the Rural Federal University of Rio de Janeiro. After harvest, the roots were minimally processed; packed; exposed to different doses of gamma radiation (0; 0.5; 1.0 and 1.5 kGy) and stored for 20 days at 8.0 deg C. Sensory evaluations were performed 1; 9; 13 and 20 days after irradiation by 12 testers who rated the overall appearance and aroma on a hedonic scale. The results indicated that the irradiated samples remained within the limit of acceptance for 20 days. In addition, the aroma was found to be a more sensitive indicator of the effect of different doses of radiation to the acceptance of the product. (author)

58

Role of the fermentation process in off-odorant formation in white pepper: on-site trial in Thailand.  

In white pepper samples, directly taken from a retting batch at a pepper production plant in Thailand, 3-methylindole, 4-methylphenol, 3-methylphenol, and butanoic acid, recently confirmed to be responsible for the characteristic fecal off-odor frequently detected in white pepper powders, were quantified by stable isotope dilution analyses. The results clearly showed that, in particular, 3-methylindole (fecal, swine-manure-like), 4-methylphenol (fecal, horse-like), and butanoic acid (cheese-like) were biochemically formed during retting, thus indicating that fermentation is the crucial step for off-odorant formation during white pepper processing. Model fermentation experiments performed with different manufacturing regimens revealed that white pepper, containing no substantial amounts of these odorants, can be produced from ripe starting material by a short fermentation under water and with frequent exchange of water. The overall aroma of such pepper was superior as compared to the aroma of white pepper produced according to the traditional procedure. PMID:16028995

59

Glucose exerts a negative effect over a peroxidase from Trichosporon asahii, with carotenoid cleaving activity  

Tobacco aroma compounds were generated via lutein cleavage by the combined action of a yeast and a bacterium identified as Trichosporon asahii and Paenibacillus amylolyticus, respectively. In this study, an inverse relationship between glucose concentration and the generation of three compounds, present in the tobacco aroma profile, was observed in mixed cultures. In order to identify the organism sensitive to the sugar effect, both were grown separately. The presence of glucose suppressed ?-ionone production by T. asahii grown with lutein. However, the biotransformation of the ionone into its reduced derivatives (7,8-dihydro-?-ionone and 7,8-dihydro-?-ionol) by P. amylolyticus was not affected by the sugar . This pointed to the cleavage of lutein, a step within the process necessary for t...

60

Characterization of kinetic parameters and the formation of volatile compounds during the tequila fermentation by wild yeasts isolated from agave juice  

The production of aroma compounds during tequila fermentation using four native yeast strains isolated from agave juice was quantified at controlled (35??C) and uncontrolled temperatures (room temperature) by gas chromatography (FID). Three of the four strains were identified as Saccharomyces cerevisiae (MTLI 1, MALI 1 and MGLI 1) and one as Kloeckera apiculata (MALI 2). Among the aroma compounds produced, acetaldehyde has the highest accumulation at the controlled temperature and before 50% of sugar was consumed. The S. cerevisiae strains produced ethyl acetate in almost the same quantity at a concentration of 5?mg/L and the K. apiculata produced six-times more (30?mg/L) than the S. cerevisiae strains, independent of the fermentation temperature. The rate and amount of 1-propanol, amyl al...

 
 
 
 
61

Formation of flavor of dry champignons (Agaricus bisporus L.)  

The composition of aroma compounds of dry champignons (Agaricus bisporus L.) were identified using capillary gas chromatography and chromatography-mass spectrometry. In total, 56 compounds were identified. It was found that the flavor of dry mushrooms was formed by the volatile compounds produced as a result of enzymatic and oxidative conversion of unsaturated fatty acids as well as in the Maillard reaction. Unsaturated alcohols and ketones containing eight carbon atoms determined the mushroom note of the product. The specific aroma of dry mushrooms was determined by a complex composition of substituted sul- fur-, oxygen-, and nitrogen-containing heterocyclic compounds as well as by aliphatic carbonyl compounds and methional. It was found that the concentrations of volatile carbonylic and ...

62

Modulation of volatile sulfur compounds by wine yeast  

Sulfur compounds in wine can be a ?double-edged sword?. On the one hand, certain sulfur-containing volatile compounds such as hydrogen sulfide, imparting a rotten egg-like aroma, can have a negative impact on the perceived quality of the wine, and on the other hand, some sulfur compounds such as 3-mercaptohexanol, imparting fruitiness, can have a positive impact on wine flavor and aroma. Furthermore, these compounds can become less or more attractive or repulsive depending on their absolute and relative concentrations. This presents an interesting challenge to the winemaker to modulate the concentrations of these quality-determining compounds in wine in accordance with consumer preferences. The wine yeast Saccharomyces cerevisiae plays a central role in the production of volatile sulfur co...

63

The composition of volatile components of dry cepe and oyster mushroom  

The composition of aroma compounds in dry cepe mushroom (Boletis edulis Fr.) and oyster mushroom (Pleurotus ostreatus Fr.) was studied using capillary gas chromatography and chromatography?mass spectrometry. In dry cepe, 53 volatile compounds were identified, and in dry oyster mushroom 41 compounds were identified. Volatile organic substances with various functional groups formed the flavor of dry mushrooms. Unsaturated alcohols and ketones with eight carbon atoms were responsible for the mushroom notes of products. Their content in dry cepe was much higher than in dry oyster mushroom. The specific aroma of dry cepe was formed by the complex mixture of methional, substituted furans, pyrazines, and pyrroles. The content of these compounds was higher in dry cepe than in dry oyster mushroom. ...

64

Effect of Oxidized Arachidonic Acid and Hexanal on the Mouse Taste Perception of Bitterness and Umami  

The oxidization of fatty acids generates many volatile compounds forming an aroma, but little is known whether mammals use gustatory sense to detect the oxidized products as a taste or only use olfactory sense to detect as an aroma. We examined in this study the effect of aqueous extracts of the compounds from autoxidized arachidonic acid (AA) ethyl ester or hexanal which is the predominant component generated from oxidized AA by the anosmic mouse licking performance to a tastant. The addition of the water extract from oxidized AA or hexanal to a quinine hydrochloride (QHCl) solution decreased the anosmic mice licking frequency at several concentrations of QHCl. Hexanal also reduced the licking frequency of anosmic mice conditioned to avoid MSG at several concentrations of monosodium glutamate (MSG). These results suggest that hexanal would affect mouse taste perception to QHCl and MSG via the gustatory sensation.   

65

Sensory quality of turnip greens and turnip tops grown in northwestern Spain  

In Galicia (northwestern Spain), Brassica rapa var. rapa L. includes turnip greens and turnip tops as vegetable products that are characterized by a particular sulfurous aroma, pungent flavor, and a bitter taste. In this work, 12 local varieties grown as turnip greens and turnip tops were evaluated to define the sensory attributes, to relate them with secondary metabolites, and to select those sensorial traits that better describe these crops. Results showed differences in the sensory profiles of B. rapa varieties. Turnip greens were significantly different regarding aroma intensity, leaf color, and salty taste, while turnip tops were for color and firmness of leaves, moistness and fibrosity in mouth, sharpness, and bitter taste. Secondary metabolites as glucosinolates in turnip greens and...

66

Characterization of the volatile profile of Brazilian Merlot wines through comprehensive two dimensional gas chromatography time-of-flight mass spectrometric detection  

Wine aroma is an important characteristic and may be related to certain specific parameters, such as raw material and production process. The complexity of Merlot wine aroma was considered suitable for comprehensive two-dimensional gas chromatography (GCxGC), as this technique offers superior performance when compared to one-dimensional gas chromatography (1D-GC). The profile of volatile compounds of Merlot wine was, for the first time, qualitatively analyzed by HS-SPME-GCxGC with a time-of-flight mass spectrometric detector (TOFMS), resulting in 179 compounds tentatively identified by comparison of experimental GCxGC retention indices and mass spectra with literature 1D-GC data and 155 compounds tentatively identified only by mass spectra comparison. A set of GCxGC experimental retention ...

67

DESCRIPTIVE PROFILE OF PEACH NECTAR SWEETENED WITH SUCROSE AND DIFFERENT SWEETENERS  

ABSTRACT Consumers are looking even more for food with pleasant characteristics in terms of flavor, appearance, aroma and texture. Thanks to technological advances, it is possible to find low-calorie products with these characteristics, with competitive prices when compared with similar products containing sucrose. In this study, peach nectar samples containing sucrose and the sweeteners aspartame, cyclamate/saccharin 2:1 blend, stevia, sucralose and acesulfame-K, were evaluated by Descriptive Quantitative Analysis. This methodology is the most complete and sophisticated technique for the sensory characterization of a product, because it allows a complete description of all the attributes existent in such product. Eleven consumers were selected by their discriminative capacity, repeatabili...

68

Introduction  

Consumers prefer food products that are tasty, healthy and convenient. Encapsulation, a process to entrap active agents into particles, is an important way to meet these demands by delivering food ingredients at the right time and place. For example, this technology may allow taste and aroma differentiation, mask bad tasting or bad smelling components, stabilize food ingredients and/or increase their bioavailability. Encapsulation may also be used to immobilize cells or enzymes in the production of food materials or products, as in fermentation or metabolite production.

69

Organic waste utilization by means of thermal cracking  

A processing technology of oil slime, tires, and polyethylene terephthalate has been investigated and suggested for use. In addition, the paths of its utilization have been found. It has been proven that the cracking of mixtures of wastes is more efficient, since it is possible to increase the key product output and to extract some specific products. Namely, the cracking of oil slime together with tires results in an increase of the output of liquid products and the content of aroma compounds by two times. By means of the cracking of polyethylene terephthalate, a profitable commercial product is extracted.

70

Coffee residues as substrates for aroma production by Ceratocystis fimbriata in solid state fermentation/ Produção de aromas por Ceratocystis fimbriata em fermentação no estado sólido utilizando resíduos da agroindústria do café como substratos  

Abstract in portuguese Neste trabalho duas diferentes cepas de Ceratocystis fimbriata foram testadas para a produção de aromas frutais em fermentação no estado sólido (FES) utilizando como substratos casca e polpa de café, suplementados com glicose. Os experimentos foram realizados em frascos Erlenmeyer de 250 mL. As condições experimentais foram: umidade inicial de 70%, adição de 20% de glicose e pH 6,0. Os frascos foram cobertos com gaze e a aeração ocorreu por difusão passiva. A (more) análise do "headspace"da cultura foi feita por cromatografia gasosa e 12 compostos foram detectados utilizando a casca de café. A análise respirométrica foi realizada para o acompanhamento do crescimento do microrganismo pela determinação do dióxido de carbono produzido. A produção de ésteres caracterizou o aroma frutal da cultura. A concentração máxima de voláteis totais foi alcançada após 72 h de cultivo em casca de café (28 µmol.L-1.g-1). Os principais compostos produzidos foram acetato de etila, etanol e acetaldeído, representando 84,7%, 7,6% and 2,0% dos voláteis totais, respectivamente. Abstract in english The ability of two different strains of Ceratocystis fimbriata for fruity aroma production by solid state fermentation (SSF) was tested on coffee pulp and coffee husk complemented with glucose as substrates. Experiments were carried out in 250 mL Erlenmeyer flasks and the experimental conditions were: 70% of initial moisture, 20% of glucose addition and pH 6.0. Aeration was made by passive diffusion through the gauze covering the flasks. Headspace analysis of the culture (more) by gas chromatography (GC) showed that 12 compounds were produced with coffee husk. Maximum total volatiles (TV) concentration was reached after 72 h of culture with coffee husk as substrate (28 µmol.L-1.g-1). Ethyl acetate, ethanol and acetaldehyde were the major compounds produced, representing 84.7%, 7.6% and 2.0% of TV, respectively. A pre-treatment with heat (100ºC/ 40 min) of substrates did not improve TV production. Respirometry analysis was used to determine the growth of the culture by measuring carbon dioxide produced. Results showed that the CO2 production follows the aroma production. This result shows the great potential for the use coffee pulp and coffee husk as substrates to microbial aroma production by solid state fermentation.

71

Antioxidants and shelf life of whole wheat bread  

Industrially produced bread normally operates with a shelf life of several weeks at room temperature and indications of storage-related off-flavour development as a consequence of lipid oxidation have been suggested. The present study has tested enrichment of whole wheat bread with alpha-tocopherol or commercially used rosemary extracts for production of bread loaves with higher oxidative stability and hence better overall sensory quality. Bread quality was evaluated by sensory profiling, determination of antioxidative capacity, determination of lipid hydroperoxides as primary oxidation products, and analysis of volatile compounds including secondary lipid oxidation products. Enrichment of bread with alpha-tocopherol resulted in higher degrees of rancid aroma and flavour in fresh samples, ...

72

Heavy flavour production at HERA. Simulation with a new Monte Carlo event generator  

The production of heavy flavours at HERA has been investigated with a new Monte Carlo generator, which describes the heavy quark production in e-p scattering via boson-gluon fusion. The program has been developed in the framework of the HERWIG Monte Carlo and, different from the existing generator AROMA from the Lund package, takes account of the initial state radiation associated with higher order QCD corrections. The banti b production at HERA energies has been studied in the two different approaches. As expected, large differences for the particle and energy flows have been found. (orig.).

73

Heavy flavour production at HERA. Simulation with a new Monte Carlo event generator  

The production of heavy flavours at HERA has been investigated with a new Monte Carlo generator, which describes the heavy quark production in e - p scattering via boson-gluon fusion. The program has been developed in the framework of the HERWIG Monte Carlo and, different from the existing generator AROMA from the Lund package, takes account of the initial state radiation associated with higher order QCD corrections. The banti b production at the HERA energies has been studied in the two different approaches. As expected, large differences for the particle and energy flows have been found. (orig.).

74

Characterization of the interaction between two food aroma components, alpha-pinene and ethyl butyrate, and ethylene-vinyl alcohol copolymer (EVOH) packaging films as a function of environmental humidity.  

The ethylene-vinyl alcohol copolymers (EVOHs) are well-known high oxygen barrier materials that are being used successfully in the design of packaging structures for oxygen-sensitive food or pharmaceutical products. Recently, there has been increasing interest in using EVOH materials to provide a high barrier to organic compounds as a means to reduce food aroma scalping. However, the barrier function of this family of materials diminishes significantly in humid environments, and it is supposed that so does the organic vapor barrier. In this work, a new sorption-based method to characterize the interaction between food aroma and polymer films for packaging as a function of relative humidity is presented and is used to determine the barrier to ethyl butyrate and alpha-pinene of EVOH at 23 degrees C. The results show that although EVOH is an excellent barrier to food aroma when dry, a property that even improves at low relative humidity (RH), the solubility and diffusivity of the compounds tested increase dramatically with humidity at medium to high water activities. However, even in the worst case (100% RH), EVOH outperforms low-density polyethylene (LDPE) as a barrier to organic vapors at least 500,000-fold. PMID:16131132

75

The chemical interactions underlying tomato flavor preferences.  

Although human perception of food flavors involves integration of multiple sensory inputs, the most salient sensations are taste and olfaction. Ortho- and retronasal olfaction are particularly crucial to flavor because they provide the qualitative diversity so important to identify safe versus dangerous foods. Historically, flavor research has prioritized aroma volatiles present at levels exceeding the orthonasally measured odor threshold, ignoring the variation in the rate at which odor intensities grow above threshold. Furthermore, the chemical composition of a food in itself tells us very little about whether or not that food will be liked. Clearly, alternative approaches are needed to elucidate flavor chemistry. Here we use targeted metabolomics and natural variation in flavor-associated sugars, acids, and aroma volatiles to evaluate the chemistry of tomato fruits, creating a predictive and testable model of liking. This nontraditional approach provides novel insights into flavor chemistry, the interactions between taste and retronasal olfaction, and a paradigm for enhancing liking of natural products. Some of the most abundant volatiles do not contribute to consumer liking, whereas other less abundant ones do. Aroma volatiles make contributions to perceived sweetness independent of sugar concentration, suggesting a novel way to increase perception of sweetness without adding sugar. PMID:22633806

76

Batchwise ethanol fermentation with shochu distillery waste  

In order to produce a shochu with a mild aroma, a new vacuum distillation precedure at low temperature of 35 to 40 centigrade was applied to shochu distillation. The resulting rice shochu distillery waste contained a large amount of viable yeast glucoamylase activity, acid protease activity, and neutral protease activity. About 10% of ethanol was produced in the fermented mash at 30 centigrade within three days. In contrast, distillery waste discharged by conventional distillation at high temperature of 55 to 60 centigrade could not be used for secondary ethanol fermentation at all. It was provided that the filtrate of secondarily-fermented distillery waste, which is containing ethanol and possessing a fine aroma fortified with higher alcohols and volatile esters during ethanol fermentation, can be useful for the production of a mirin-like liquor for cooking, Akazake,'' a characteristic red-colored, sweet alcoholic beverage produced in Kumamoto prefecture only, and a bath additive containing ethanol, a fine aroma, and enzymes. 15 refs, 2 figs., 3 tabs.

77

[The composition of volatile components of dry cepe and oyster mushroom].  

The composition of aroma compounds in dry cepe mushroom (Boletis edulis Fr.) and oyster mushroom (Pleurotus ostreatus Fr.) was studied using capillary gas chromatography and chromatography-mass spectrometry. In dry cepe, 53 volatile compounds were identified, and in dry oyster mushroom 41 compounds were identified. Volatile organic substances with various functional groups formed the flavor of dry mushrooms. Unsaturated alcohols and ketones with eight carbon atoms were responsible for the mushroom notes of products. Their content in dry cepe was much higher than in dry oyster mushroom. The specific aroma of dry cepe was formed by the complex mixture of methional, substituted furans, pyrazines, and pyrroles. The content of these compounds was higher in dry cepe than in dry oyster mushroom. The content of aromatic and aliphatic aldehydes with six, nine, and ten carbon atoms was higher in dry oyster mushroom. The differences in the qualitative and quantitative composition of volatile compounds are responsible for more intensive and pleasant aroma of dry cepe in comparison to that of dry oyster mushroom. PMID:19845295

78

Volatiles produced by Staphylococcus xylosus and Staphylococcus carnosus during growth in sausage minces : Part II. The influence of growth parameters  

Aseptic model minces inoculated with commercial samples of either Staphylococcus xylosus or Staphylococcus carnosus were prepared in accordance with an experimental design investi-gating the effect of seven parameters: fermentation temperature, pH, salt, nitrate, glucose, ascorbate and the access of air. Volatiles produced by the cultures were collected during growth, identified and quantified. The data were analysed by partial least squares regression. The results showed that oxygen in general had more influence on the aroma producing capacity of Staphylococcus xylosus than of Staphylococcus carnosus which was more affected by nitrate and glucose. The two strains differed mostly with regards to pH. Aroma production by both strains was strongly related to growth - either positively or negatively depending on compound. Potent aroma compounds such as methyl-branched aldehydes and acids arising from degradation of leucine, isoleucine and valine, and aromatic compounds arising from phenylalanine were produced in lower amounts when the bacteria grew well, i.e. produced cell mass, whereas the opposite was the case for compounds such as sulfides and ketones.

79

Sensory evaluation of rice fortified with iron/ Análise sensorial de arroz fortificado com ferro  

Abstract in portuguese O objetivo deste trabalho foi verificar diferenças sensoriais entre o arroz convencional e o arroz fortificado com ferro e determinar a aceitação deste pelo consumidor. As diferenças entre os dois tipos de arroz foram analisadas por meio do teste Duo-Trio, com 37 julgadores não treinados. O Teste de Aceitação avaliou aparência geral, cor, aroma e sabor do arroz fortificado com 43 julgadores não treinados, utilizando escala hedônica de sete pontos, com extremos " (more) desgostei muitíssimo" e "gostei muitíssimo". Não houve diferenças significativas entre as amostras analisadas pelo Teste Duo-Trio. Os valores médios obtidos no Teste de Aceitação para os atributos avaliados (aparência geral, cor, aroma e sabor) foram entre 5,6 e 5,9; correspondentes a "gostei" e "gostei muito" de acordo com a escala hedônica. O ferro não causou alterações às características sensoriais do produto final, e o arroz fortificado foi bem aceito. Abstract in english The objective of this study was to examine sensory differences between conventional rice and iron-fortified Ultra Rice rice (UR) and determine consumer acceptance. Differences between both types of rice were analyzed using the Duo-Trio Test on 37 non-trained judges. The Acceptance Test evaluated general rice appearance, color, aroma and taste by 43 non-trained judges, using a 7-point hedonic scale with extremes ranging from "really disliked" and "really liked." There were (more) no significant differences between the analyzed samples of conventional rice and UR rice using Duo-Trio Test. Mean values from the Acceptance Test for the evaluated attributes (general appearance, color, aroma e taste) were 5.6 and 5.9, corresponding to "liked" and "really liked" according to the hedonic scale, respectively. The iron did not alter the sensory characteristics of the final product, and the iron-fortified rice was well accepted.

80

Influence of thermal treatment of wood on the aroma of a sugar cane spirit (cachaça) model-solution/ Influência do termotratamento da madeira no aroma de uma solução-modelo de cachaça  

Abstract in portuguese As bebidas alcoólicas são, geralmente, envelhecidas em tonéis de madeira fabricados a partir de espécies do gênero Quercus sp. Devido ao alto custo de aquisição e necessidade de importação, existe demanda por alternativas de uso de outras espécies nativas e da incorporação de novas tecnologias que aumentem a competitividade da cachaça brasileira. Sabe-se que, com a aplicação de termotratamento, vários compostos são alterados, desenvolvem-se aromas, altera (more) -se a coloração e as bebidas adquirem gostos mais agradáveis. Este trabalho mostra a diferença significativa entre soluções-modelo hidroalcoólicas de cachaça, envelhecidas em diferentes espécies de madeira, em suas formas termotratadas e não termotratadas, avaliadas em relação a seu aroma. O teste de aceitação aplicado verificou as soluções preferidas pelos provadores, nas condições determinadas do teste. Abstract in english The aging process of alcoholic beverages is generally conducted in wood barrels made with species from Quercus sp. Due to the high cost and the lack of viability of commercial production of these trees in Brazil, there is demand for new alternatives to using other native species and the incorporation of new technologies that enable greater competitiveness of sugar cane spirit aged in Brazilian wood. The drying of wood, the thermal treatment applied to it, and manufacturin (more) g techniques are important tools in defining the sensory quality of alcoholic beverages after being placed in contact with the barrels. In the thermal treatment, several compounds are changed by the application of heat to the wood and various studies show the compounds are modified, different aromas are developed, there is change in color, and beverages achieve even more pleasant taste, when compared to non-treated woods. This study evaluated the existence of significant differences between hydro-alcoholic solutions of sugar cane spirits elaborated from different species of thermo-treated and non-treated wood in terms of aroma. An acceptance test was applied to evaluate the solutions preferred by tasters under specific test conditions.

 
 
 
 
81

Análise sensorial de diferentes marcas comerciais de café (Coffea arabica L.) orgânico/ Sensory evaluation of differents comercial marks of the organic coffee (Coffea arabica l.)  

Abstract in portuguese Produtos orgânicos são polêmicos quanto a sua qualidade sensorial. Neste estudo foi realizado um teste de aceitação em relação a um conjunto de atributos: cor, aroma, sabor e impressão global, no qual sessenta e seis consumidores avaliaram quatro amostras de café orgânico e uma amostra de café convencional de quatro diferentes marcas comerciais. Para a realização desse teste utilizou-se uma escala hedônica de nove pontos e os resultados obtidos foram avaliad (more) os por meio de Mapa de Preferência Interno (MDPREF). O MDPREF demonstrou que a amostra de café orgânico ORG-4 obteve maior aceitação pelos consumidores em relação aos quatro atributos avaliados, mostrando que nessa marca de café os atributos em conjunto torna-a bem mais apreciada. A marca de café orgânico ORG-1 foi menos preferida quanto aos atributos cor, sabor e impressão global. A amostra de café CON foi menos aceita quanto ao atributo aroma. Abstract in english Organic products are controversial in relation to sensory quality. In that study an acceptance test was accomplished in relation to a group of attributes: color, aroma, flavor and overall impression, where sixty six consumers evaluated four samples of organic coffee and a sample of conventional coffee of four different commercial marks. For the accomplishment of that test a hedonic scale of nine points was used and the obtained results were analyzed by Internal Preference (more) Map (PREFMD). PREFMD demonstrated that the sample of organic coffee ORG-4 obtained larger acceptance for the consumers in relation to the four attributes, showing that in that mark of coffee the attributes together turn it well appreciated. The mark of organic coffee ORG-1 was less accepted by the consumers in relation to the attributes color, flavor and overall impression. For the attribute aroma, the coffee CON was the one of smaller preference.

82

High-cell-density fermentation of Saccharomyces cerevisiae for the optimisation of mead production.  

Mead is a traditional drink that contains 8%-18% (v/v) of ethanol, resulting from the alcoholic fermentation of diluted honey by yeasts. Mead fermentation is a time-consuming process and the quality of the final product is highly variable. Therefore, the present investigation had two main objectives: first, to determine the adequate inoculum size of two commercial wine-making strains of Saccharomyces cerevisiae for the optimisation of mead fermentation; and second, to determine if an increase in yeast pitching rates in batch fermentations altered the resulting aroma profiles. Minor differences were detected in the growth kinetics between the two strains at the lowest pitching rate. With increasing pitching rates net growth of the strain ICV D47 progressively decreased, whereas for the QA23 the increasing inoculum size had no influence on its net growth. The time required to reach the same stage of fermentation ranged from 24 to 96 h depending on the inoculum size. The final aroma composition was dependent on the yeast strain and inoculum size. Fourteen of the twenty-seven volatile compounds quantified could contribute to mead aroma and flavour because their concentrations rose above their respective thresholds. The formation of these compounds was particularly pronounced at low pitching rates, except in mead fermented by strain ICV D47, at 10(6) CFUs/mL. The esters isoamyl acetate, ethyl octanoate and ethyl hexanoate were the major powerful odourants found in the meads. The results obtained in this study demonstrate that yeast strain and inoculum size can favourably impact mead's flavour and aroma profiles. PMID:23122509

83

ESTUDO DO PROCESSO DA EXTRAÇÃOSUPERCRÍTICA DE ÓLEOS ESSENCIAIS DE PRODUTOS NATURAIS  

Abstract in portuguese A desterpenação do óleo essencial de laranja é uma preocupação da indústria cítrica. Esta consiste em concentrar os componentes oxigenados do óleo, que são os maiores responsáveis pelo sabor e aroma deste, reduzindo a fração terpênica que se degrada facilmente promovendo a formação de compostos com sabores e aroma indesejáveis. Esta fração oleosa rica em compostos oxigenados pode ser empregada em bebidas e outros alimentos como aromatizante mais agradá (more) vel. Um dos métodos em estudo para a concentração dos compostos oxigenados do óleo essencial de laranja é a adsorção na sílica gel, seguida da dessorção fracionada com dióxido de carbono pressurizado. Este processo permite a obtenção de frações oleosas mais concentradas em compostos oxigenados que outros métodos convencionais. Neste trabalho foi utilizado o modelo de difusão em sólido aplicado em leito fixo, empregando a solução analítica proposta por Rosen em 1952, para o estudo do modelamento do processo de dessorção do óleo essencial de laranja com dióxido de carbono supercrítico. Abstract in english The desterpenation of the orange essential oil is a concern of the citric industry. The process consists of concentrating the oxygenated components of the oil which are the substances responsible for the oil flavor and aroma, by reducing the terpenic fraction that easily degrades promoting the formation of compounds with undesirable flavors and aroma. This fraction rich in oxygenated substances can be used as an additive in the food industry. One of the methods for concen (more) tration of oxygenated compounds is the adsorption of the oil in silica gel, followed by desorption with pressurized carbon dioxide. This process allows to obtain a product more concentrated on oxygenated compounds than conventional methods. In this work the diffusion model in solid applied to a fixed-bed was used, with the analytic solution proposed by Rosen in 1952, to model the process of desorption of orange essential oil from a silica gel bed with supercritical carbon dioxide.

84

O aroma ambiental e sua relação com as avaliações e intenções do consumidor no varejo/ Ambient scent and its relationship with consumer evaluations and intentions in retail/ El aroma ambiental y su relación con las evaluaciones e intenciones del consumidor en el comercio minorista  

Abstract in portuguese A atmosfera de uma loja é capaz de provocar emoções e comportamentos que estimulam a compra. Entre as suas dimensões, está o aroma ambiental, adicionado artificialmente ao ambiente. Este artigo investiga a relação entre a presença de aroma ambiental no varejo e as avaliações de loja, ambiente de loja e produtos, além das intenções comportamentais relativas ao retorno e ao tempo gasto na loja. A pesquisa teve uma etapa exploratória, exame de publicações em (more) fisiologia, psicologia e comportamento do consumidor, para construção do referencial teórico e formulação das hipóteses, e outra causal, quase experimento, para identificar as relações de causa e efeito na presença de aroma. O estudo foi conduzido em uma butique de frutos do mar, e os instrumentos de coleta de dados, escalas de diferencial semântico, basearam-se em pesquisas similares. As análises incluíram técnicas de estatística descritiva e teste de hipóteses. Os resultados revelaram que a presença de aroma ambiental não aumentou as avaliações nem a intenção de retorno, mas reteve o consumidor por mais tempo na loja. Abstract in spanish La atmósfera de un negocio es capaz de generar emociones y comportamientos que estimulan la compra. Entre sus dimensiones, está el aroma ambiental, adicionado de modo artificial al ambiente. Este artículo averigua la relación entre la presencia de aroma ambiental en el comercio minorista y las evaluaciones de negocio, ambiente de negocio y productos, además de las intenciones de comportamiento con respecto al retorno y al tiempo dedicado al negocio. La investigación (more) tuvo una etapa exploratoria, examen de publicaciones en fisiología, psicología y comportamiento del consumidor, para construcción del referencial teórico y formulación de las hipótesis, y otra causal, casi-experimento, para identificar las relaciones de causa y efecto en la presencia del aroma. El estudio fue conducido en una especie de boutique para frutos del mar y, los instrumentos de colecta de datos, escalas de diferencial semántico, basaranse en investigaciones similares. Los análisis han incluido técnicas de estadística descriptiva y teste de hipótesis. Los resultados han revelado que la presencia de aroma ambiental no aumentó las evaluaciones ni la intención del retorno, pero mantuvo el consumidor por más tiempo en el negocio. Abstract in english The atmosphere of a store can be used to produce specific emotions that enhance purchase probability, and the ambient scent, artificially added, is among its dimensions. This article investigates the relationship between the presence of an ambient scent in a retail store, and customers' evaluation of the store, its environment and products, as well as the behavioral intentions related to return and time spent in the store. The research design included an exploratory stage (more) , examination of publications in the fields of physiology, psychology and consumer behavior, to provide the conceptual background and to formulate research hypothesis; and a causal stage, quasi-experiment, to verify the effects of scent presence. Semantic differential scales were employed for data collection. Descriptive statistics and hypothesis test were performed for data analysis and the results revealed that the scent presence did not improve the evaluations or the intent to return but retained the consumer longer in the store.

85

Avaliação química de substitutos de cacau e estudo sensorial de achocolatados formulados/ Chemical evaluation of cocoa substitutes and study of formulated chocolate drink powder  

Abstract in portuguese O cacau em pó é obtido a partir da pasta de cacau preparada com sementes que passaram pelos processos de fermentação, secagem, torrefação, moagem e prensa (para separação da manteiga de cacau), podendo ser utilizado em formulações de achocolatados que além de cacau em pó são produzidos com: açúcar, aroma e outros ingredientes constantes da formulação. Nos países líderes de produção, o preço do cacau é afetado pelo clima, pragas e fatores políticos. (more) Substitutos de cacau são substâncias que podem entrar na formulação de produtos que utilizam cacau em pó para substituí-lo parcial ou totalmente, com a finalidade de diminuição do preço do produto final, garantia de qualidade dos produtos dependentes de cacau na entressafra ou mesmo na possível ausência do cacau em pó no mercado. Os substitutos escolhidos para avaliação foram: farinha tostada de alfarroba, cupuaçu em pó, composto da semente de cacau e aromas. Os objetivos foram: avaliar quimicamente (composição centesimal e teor de metilxantinas) os substitutos de cacau e sensorialmente, sob a forma de achocolatados. Concluiu-se que os produtos analisados apresentam diferentes propriedades químicas daquelas do cacau, sendo que os aromas foram preferidos nos testes sensoriais. Abstract in english Cocoa powder is obtained from cocoa paste. It is prepared with fermented, dried, toasted, grinded and pressed beans (to separate cocoa butter). It can be used to produce chocolate powders, which contains cocoa powder, sugar, chocolate flavor and other ingredients. In the major producing countries, the price of cocoa by-product is affected by the climate, plagues and political factors. Cocoa substitutes are substances that can total or partially substitute cocoa powder in (more) the formulation of different products with the purpose of reducing the final price, guaranteeing the quality in the off season or even during a possible short availability of cocoa powder in the market. The substitutes chosen for evaluation include toasted carob powder, cupuaçu powder, cocoa seed compounds and aroma. The objectives of this study were evaluate chemical parameters (centesimal composition and methylxanthines) of the cocoa powder substitutes and carry out a sensorial evaluation of chocolate drink powders formulated with the substitutes. As results, the substitutes showed different chemical properties from those of cocoa, and the sensorial tests showed preference to the aroma.

86

Saccharomyces cerevisiae: a potential stereospecific reduction tool for biotransformation of mono- and sesquiterpenoids  

Abstract Terpenes and terpenoids are among the key impact substances in the food and fragrance industries. Equipped with pharmacological properties and applications as ideal precursors for the biotechnological production of natural aroma chemicals, interests in these compounds have been escalating. Hence, the syntheses of new derivatives that can show improved properties are often called for. Stereoselective biotransformation offers several benefits to increase the rate of production, in terms of both the percentage yield and its enantiomeric excesses. Baker's yeast (Saccharomyces cerevisiae) is broadly used as a whole cell stereospecific reduction biocatalyst, due to its capability in reducing carbonyls and carbon-carbon double bonds, which also extends its functionality as a versatile bi...

87

Combination of newly developed high quality Fuqu with traditional Daqu for Luzhou-flavor liquor brewing  

Application of a compound starter composed of traditional Daqu, high quality Fuqu developed previously in our lab, and alcohol-producing and aroma-producing yeasts in the brewing of Luzhou-flavor liquor was investigated. Compared with traditional Daqu, the compound starter demonstrated apparently higher starch utilization and alcohol productivity both in flasks and in pits. Flavor ingredient analyses showed that the flavor ingredient compositions of liquors produced with the compound starter were similar to those obtained with the traditional process. With appropriate after treatments, the compound starter may be applied in distilleries for elevating the productivity of traditional liquor or producing high quality new-style distilled liquor. As starch utilization can be increased significa...

88

Physicochemical and sensory profile of rice bran roasted in microwave/ Perfil físico-químico e sensorial de farelos de arroz torrados em micro-ondas  

Abstract in portuguese Este trabalho objetivou avaliar as mudanças físicas, químicas e sensoriais de farelos de três cultivares de arroz em função do tempo de torra em micro-ondas. Foram estudados 3 cultivares de arroz, BRS Sertaneja (S), BRS Primavera (P) e Irga 417 (I), determinando-se os parâmetros de cor (L*, a* e b*) aos 6, 9, 12, 15 e 18 minutos de torração. Após aplicação do teste de diferença do controle, selecionaram-se farelos de arroz com características de sabor e arom (more) a distintas: S e P torrados por 9 e 15 minutos e I torrado por 9, 12 e 15 minutos. Essas amostras foram caracterizadas pela análise sensorial descritiva de Perfil Livre e quanto composição química. Quanto mais longa a torração, mais intenso o aroma e sabor de torrado dos farelos, apresentando sabor e aroma mais doce o da IRGA 417 torrado por 12 minutos. Após a torração, o farelo continuou um alimento rico em proteínas e lipídios, aumentou o conteúdo de fibra e diminuiu o teor de açúcares redutores e ácido fítico. O farelo de arroz torrado por 12 minutos em micro-ondas pode ser uma opção viável para melhorar as características sensoriais, funcionais e nutricionais do farelo de arroz. Abstract in english The purpose of this study was to evaluate the physical, chemical, and sensory changes in bran from three rice cultivars according to microwave roasting time. This study analyzed three rice cultivars, BRS Sertaneja (S), BRS Primavera (P), and IRGA 417 (I) determining the color parameters (L*, a*, and b *) at 6, 9, 12, 15, and 18 minutes of roasting time. After applying the difference from control test, the rice brans with different characteristics aroma and flavor were sel (more) ected: S and P roasted for 9 and 15 minutes and IRGA 417 roasted for 9, 12, and 15 minutes. These samples were characterized by Free-Choice Profile descriptive sensory analysis, and their chemical composition was also determined. The longer the roasting process, the higher the roasted flavor intensity and aroma. The IRG 417 cultivar roasted for 12 minutes showed a sweeter flavor and aroma. After roasting, the brans remained rich in protein and lipid and presented higher fiber content and lower reducing sugar and phytic acid content. Microwave roasting for 12 minutes can be a viable option for improving the sensory functional and nutritional characteristics of the rice bran considering its use in food products.

89

Retention of short chain fatty acids under drying and storage conditions/ Retençao de ácidos graxos de cadeia curta sob secagem e condições de estocagem  

Abstract in portuguese Permeado de soro de queijo foi usado como um substrato para a fermentação de Propionibacterium freudenreichi PS1 para produção de ácidos graxos de cadeia curta, constituintes do bioaroma de queijo suíço. O bioaroma líquido foi encapsulado por secagem por atomização sob diferentes condições de temperatura de entrada de ar e vazão de alimentação. Um estudo foi realizado sobre a estabilidade do bioaroma durante estocagem em embalagens laminadas a 30 °C por 90 (more) dias, usando o produto que mostrou maior retenção de ácido acético e propiônico. Os resultados mostraram que a melhores condições de secagem foram uma temperatura do ar de entrada de 180 °C e taxa de alimentação de 24 g/min, resultando em partículas com superfície lisa e poucas invaginações e microfissuras. No entanto, 72% do ácido acético e 80% do ácido propiônico foram perdidos durante a estocagem, mostrando que o material de parede usado foi inadequado para garantir a estabilidade do produto. Abstract in english Cheese whey permeate was used as a substrate for the fermentation of Propionibacterium freudenreichi PS1 for the production of short chain fatty acids, components of the bio-aroma of Swiss cheese. The liquid bio-aroma was encapsulated by spray drying under different conditions of air inlet temperature and feed rate. A study was carried out on the stability of the bio-aroma during storage in laminated packages at 30 °C for 96 days using the product showing the greatest re (more) tention of acetic and propionic acids. The results showed that the best drying conditions were an air entrance temperature of 180 °C and a feed rate of 24 g/min resulting in particles with a smooth surface and few invaginations and micro-fissures. However, 72% of the acetic acid and 80% of the propionic acid were lost during storage showing that the wall material used was inadequate to guarantee product stability.

90

A Comparison of the Volatile Compounds in Several Green Teas  

Differences in the aromas of steamed green teas are due to the cultivars, the climate and the production process. We compare the volatile compounds found in steamed green tea of the same cultivar (cv. Yabukita (Camellia sinensis var. sinensis)) but produced in different places (Saitama, Shizuoka, Mie, Nara, Kyoto, Saga and Miyazaki prefectures). A total of 75 volatile compounds were identified by GC and GC/MS. The results showed observed differences in the quantities of these compounds. Principal component analysis (PCA) was performed for the GC data to investigate the relationship between green teas from different places. Each green tea was found to contain certain characteristic compounds.   

91

Aromatic components of the leaves of the New Zealand lemonwood tree Pittosporum eugenioides.  

The major aromatic components of the essential leaf oil of the New Zealand lemonwood tree Pittosporum eugenioides are octyl acetate (33%), terpinen-4-ol (13%), decanol (6%) and (Z)-hex-3-enol (5%). These products are responsible for the characteristic Citrus-like aroma which is detected when the leaves are crushed, a phenomenon which provided the species with its common name. The major component of the oil, octyl acetate is also an abundant component of the essential oils of Heracleum and Boswellia species. PMID:15018048

92

Metabolic engineering in strawberry fruit uncovers a dormant biosynthetic pathway  

Wild strawberry (Fragaria vesca) fruit contains several important phenylpropene aroma compounds such as eugenol, but cultivated varieties are mostly devoid of them. We have redirected the carbon flux in cultivated strawberry (Fragaria×ananassa) fruit from anthocyanin pigment biosynthesis to the production of acetates of hydroxycinnamyl alcohols, which serve as the precursors of the phenylpropenes, by downregulating the strawberry chalcone synthase (CHS) via RNAi-mediated gene silencing and, alternatively, by an antisense CHS construct. Simultaneous heterologous overexpression of a eugenol (EGS) and isoeugenol synthase (IGS) gene in the same cultivated strawberry fruits boosted the formation of eugenol, isoeugenol, and the related phenylpropenes chavicol and anol to concentrations o...

93

Evaluation of sensorial analysis in mate (Ilex Paraguariensis) processed by gamma radiation  

Mate (Ilex paraguariensis) is a native species from South America which is widely consumed as chimarrao (made white hot water) and terere (made white could water) beverages. One of the basic questions for the food area is the relation between the quality observed by the consumers and the presence of compounds responsible for its flavor and aroma, essential parameters of the food quality. The radiation food processing has been demonstrating great effectiveness in the combat of pathogenic agents while little compromising nutritional value and sensorial properties of foods. This boarding affects directly the food industry, which represent quality and aggregate product value. (author)

94

The impact of co-inoculation with Oenococcus oeni on the trancriptome of Saccharomyces cerevisiae and on the flavour-active metabolite profiles during fermentation in synthetic must  

Co-inoculation of commercial yeast strains with a bacterial starter culture at the beginning of fermentation of certain varietal grape juices is rapidly becoming a preferred option in the global wine industry, and frequently replaces the previously dominant sequential inoculation strategy where bacterial strains, responsible for malolactic fermentation, are inoculated after alcoholic fermentation has been completed. However, while several studies have highlighted potential advantages of co-inoculation, such studies have mainly focused on broad fermentation properties of the mixed cultures, and no data exist regarding the impact of this strategy on many oenologically relevant attributes of specific wine yeast strains such as aroma production. Here we investigate the impact of co-inoculation...

95

Molecular Structure of Methyl mercaptan  

Methyl mercaptan is a colorless, flammable and volatile sulfur compound that is responsible for the rotten cabbage or burnt rubber aroma. This substance can be found in the blood, brain, and other tissues of humans and other animals, it is released from animal feces and occurs naturally in foods such as nuts and cheeses. The formation of methyl mercaptan is commonly noted as a problem in the process of the post-fermentation of wine. Despite the repulsive smell methyl mercaptan is used as a gas odorant, as an intermediate in the production of fungicides, as jet fuel additives, flavoring agents, plastics, as well as in the synthesis of methionines, and as catalysts.

96

Production-integrated environmental protection in wood processing with recycling of wood constituents, process water and heat; Produktionsintegrierter Umweltschutz bei der Herstellung von Holzwerkstoffen mit Rueckgewinnung von Holzinhaltsstoffen, Prozesswasser und Waerme  

During wood drying processes, volatile original wood constitutents are released. The most important of these are terpene compounds which are used in the chemical industry as scents or aromas. Steam drying of wood chips in a closed gas loop opens up the economically efficient, production-integrated extraction of terpene compounds from the dried vapours. (orig.) [German] Bei der Trocknung von Holz werden fluechtige originaere Holzinhaltsstoffe freigesetzt. Besondere Bedeutung kommt den Terpenverbindungen zu, da diese als Rohstoffe in der chemischen Industrie (Duft- und Aromastoffherstellung) eingesetzt werden. Mit der Dampftrocknung von Holzspaenen im geschlossenen Gaskreislauf bietet sich erstmals die Moeglichkeit einer wirtschaftlichen produktionsintegrierten Gewinnung von Terpenverbindungen aus den angereicherten Trocknerbrueden. (orig.)

97

Optimization of honey-must preparation and alcoholic fermentation by Saccharomyces cerevisiae for mead production.  

Mead fermentation is a time-consuming process, often taking several months to complete. Despite of the use of starter cultures several problems still persist such as lack of uniformity of the final products, slow or premature fermentation arrest and the production of off-flavors by yeast. Thus the aim of this study was to optimize mead production through the use of an appropriate honey-must formulation to improve yeast performance alcoholic fermentation and thereby obtain a high quality product. Honey-must was centrifuged to reduce insoluble solids, pasteurized at 65°C for 10 min, and then subjected to different conditions: nitrogen supplementation and addition of organic acids. Although the addition of diammonium phosphate (DAP) reduced fermentation length, it did not guarantee the completeness of the fermentation process, suggesting that other factors could account for the reduced yeast activity in honey-must fermentations. Sixteen yeast-derived aroma compounds which contribute to the sensorial quality of mead were identified and quantified. Global analysis of aromatic profiles revealed that the total concentration of aroma compounds in meads was higher in those fermentations where DAP was added. A positive correlation between nitrogen availability and the levels of ethyl and acetate esters, associated to the fruity character of fermented beverages, was observed whereas the presence of potassium tartrate and malic acid decreased, in general, their concentration. This study provides very useful information that can be used for improving mead quality. PMID:20937538

98

Cloning and inactivation of a branched-chain-amino-acid aminotransferase gene from Staphylococcus carnosus and characterization of the enzyme.  

Staphylococcus carnosus and Staphylococcus xylosus are widely used as aroma producers in the manufacture of dried fermented sausages. Catabolism of branched-chain amino acids (BCAAs) by these strains contributes to aroma formation by production of methyl-branched aldehydes and carboxy acids. The first step in the catabolism is most likely a transamination reaction catalyzed by BCAA aminotransferases (IlvE proteins). In this study, we cloned the ilvE gene from S. carnosus by using degenerate oligonucleotides and PCR. We found that the deduced amino acid sequence was 80% identical to that of the corresponding enzyme in Staphylococcus aureus and that the ilvE gene was constitutively expressed as a monocistronic transcript. To study the influence of ilvE on BCAA catabolism, we constructed an ilvE deletion mutant by gene replacement. The IlvE protein from S. carnosus was shown mainly to catalyze the transamination of isoleucine, valine, leucine, and, to some extent, methionine using pyridoxal 5'-phosphate as a coenzyme. The ilvE mutant degraded less than 5% of the BCAAs, while the wild-type strain degraded 75 to 95%. Furthermore, the mutant strain produced approximately 100-fold less of the methyl-branched carboxy acids, 2-methylpropanoic acid, 2-methylbutanoic acid, and 3-methylbutanoic acid, which derived from the BCAA catabolism, clearly emphasizing the role of IlvE in aroma formation. In contrast to previous reports, we found that IlvE was the only enzyme that catalyzed the deamination of BCAAs in S. carnosus. The ilvE mutant strain showed remarkably lower growth rate and biomass yield compared to those of the wild-type strain when grown in rich medium. Normal growth rate and biomass yield were restored by addition of the three BCAA-derived alpha-keto acids, showing that degradation products of BCAAs were essential for optimal cell growth. PMID:12147502

99

Intraspecific genotypic variability determines concentrations of key truffle volatiles  

Summary - Aroma variability in truffles has been attributed to maturation (Tuber borchii), linked to environmental factors (Tuber magnatum), but the involvement of genetic factors has been ignored. We investigated aroma variability in Tuber-uncinatum, a species with wide distribution. Our aim was to assess aroma variability at different spatial scales (i.e. trees, countries) and to quantify how aroma was affected by genotype, fruiting body maturity, and geographical origin. - A volatile fingerprinting method was used to analyze the aroma of 223 T.uncinatum fruiting bodies from seven European countries. Maturity was estimated from spore melanization. Genotypic fingerprinting was performed by amplified fragment length polymorphism (AFLP). - Discriminant analysis revealed that, regardless of ...

100

Concentrado proteico do soro melhora a qualidade sensorial de sobremesa láctea diet/ Whey protein concentrate improves the sensory quality of free-fat dairy desserts  

Abstract in portuguese Alimentos isentos ou de baixo nível de gordura constituem um desafio para a indústria de alimentos. Nesse contexto, este trabalho teve como objetivo estudar o efeito da adição de concentrado proteico de soro (CPS) nas características sensoriais e aceitabilidade de sobremesas lácteas sem gordura. Quatro formulações foram desenvolvidas com diferentes concentrações de CPS (0%, 1,5%, 3,0% e 4,5% m v-1) e caracterizadas sensorialmente por meio da Análise Descritiva. (more) A aceitabilidade das formulações foi avaliada por 94 consumidores que utilizaram escala hedônica de nove pontos. As sobremesas foram caracterizadas por oito atributos sensoriais: cor, firmeza, resistência ao corte, brilho, consistência, gomosidade, aroma e sabor de baunilha. As formulações contendo 3,0 e 4,5% de CPS apresentaram maior intensidade de todos os atributos sensoriais. A adição de CPS foi efetiva na composição da textura das sobremesas lácteas diet, além de realçar a cor, sabor e aroma do produto. As formulações contendo 1,5 e 3,0% de CPS foram as mais aceitas, evidenciando que a utilização do CPS nessas concentrações favoreceu a aceitabilidade do produto, proporcionando características sensoriais agradáveis aos consumidores. Abstract in english Foods free or low-fat constituted are a challenge for the food industry. Thus, the objective of this research was to study the effect of the addition of whey protein concentrate (WPC) in the sensory profile and acceptability of dairy desserts free-fat. Four formulations had been developed with different WPC concentrations (0%, 1.5%, 3.0% or 4.5%, mass%) and sensory characterized by Descriptive Analysis. The acceptability of the formulations was evaluated by 94 consumers w (more) ho had used the nine-point hedonic scale. Dairy desserts were characterized by eight sensory attributes: color, firmness, resistance to cut, brightness, thickness, gumminess, aroma and vanilla flavor. The formulations containing 3.0 and 4.5% of WPC presented greater intensity of all the attributes. The addition of WPC was effective in the composition of the texture of free-fat dairy desserts and enhances color, flavor and aroma of the product. The formulations with 1.5 and 3.0% WPC had been most accepted, showing that the use of WPC in these concentrations favored the acceptability of the product, providing pleasant sensory characteristics to consumers.

 
 
 
 
101

Chemical profile of sugarcane spirits produced by double distillation methodologies in rectifying still/ Aspectos da composição química de aguardente de cana-de-açúcar produzida por metodologias de dupla destilação em alambique retificador  

Abstract in portuguese O objetivo deste trabalho foi determinar o perfil físico-químico da aguardente de cana-de-açúcar produzida por diferentes metodologias de dupla destilação em alambique retificador. Mosto fermentado de caldo de cana-de-açúcar foi destilado seguindo três metodologias de dupla destilação: a empregada para a produção de cognac, a empregada na produção de whisky e a metodologia da proporção porcentual 10-80-10, referente aos volumes das frações cabeça, cora (more) ção e cauda do destilado. Para comparação, também foi produzida uma aguardente monodestilada. Os destilados foram analisados quimicamente quanto às concentrações de etanol, cobre, acidez volátil, furfural e hidroximetilfurfural, aldeídos, ésteres, metanol e álcoois superiores. As aguardentes foram também avaliadas sensorialmente quanto aos atributos de aroma, sabor e preferência. Comparada com a monodestilação, a dupla destilação melhorou a qualidade química das aguardentes, pois proporcionou redução das concentrações de ácidos, de aldeídos, de ésteres, de metanol, de álcoois superiores e, consequentemente, do coeficiente de congêneres das aguardentes. Independentemente da metodologia empregada, as aguardentes produzidas por dupla destilação obtiveram maior aceitação sensorial que a aguardente monodestilada. Dentre as aguardentes duplamente destiladas, a produzida segundo a metodologia do uísque obteve as maiores notas dos provadores quanto aos parâmetros de aroma e sabor e também foi a preferida. Abstract in english The objective of this study was to determine the chemical profile of sugarcane spirits produced by different double distillation methodologies in rectifying still. Fermented sugarcane juice was distilled in rectifying still according to three double distillation methodologies: the methodology used for cognac production; the methodology used for whisky production; and the 10-80-10 percentage composition methodology, referring to the volumes of head, heart and tail of the d (more) istillate fractions from the second distillation. For comparison purposes, a simple distilled spirit was also produced. The distillates were analyzed for concentrations of ethanol, copper, volatile acidity, furfural and hydroxymethylfurfural, aldehydes, esters, methanol and higher alcohols. The spirits were also evaluated on the sensory attributes of aroma, taste and preference. Compared to simple distillation, double distillation improved the chemical quality of the spirits, since it has reduced the concentrations of acids, aldehydes, esters, methanol, higher alcohols and, consequently, their coefficient of congeners. Regardless of the methodology employed, the double distillation improved the sensory quality of the spirits since they obtained higher sensory acceptance in relation to spirits produced by simple distillation. Among double distilled spirits, the one produced according to whisky methodology obtained the best scores from appraisers on the aroma and flavor parameters and it was also the most preferred.

102

Evaluation of aroma active compounds in Tuber fruiting bodies by gas chromatography?olfactometry in combination with aroma reconstitution and omission test  

The aroma active compounds of three Tuber fruiting bodies (i.e., Tuber himalayense, Tuber indicum, and Tuber sinense) were firstly systematically evaluated by instrumental gas chromatography?olfactometry combining with quantitative analysis, aroma reconstitution, and omission tests. Twelve aroma active compounds were characterized by aroma extract dilution analysis, and 3-(methylthio) propanal, 3-methylbutanal, and 1-octen-3-ol with the highest flavor dilution (FD) factor (i.e., 1,024?2,048) were suggested as key contributors to the aroma. Odor activity value (OAV) was employed to determine the relative contribution of each compound to the aroma, and the compound with the highest FD factor also had the highest OAV (i.e., 10,234?242,951). Then, the synthetic blends of odorants (aroma recons...

103

Growth and aroma production by Staphylococcus xylosus, S- carnosus and S-equoum - a comparative study in model systems  

A laboratory medium inoculated with 20 different Staphylococcus strains was prepared in accordance with a full Factorial experimental design investigating the effect of temperature. pH, NaCl and glucose on growth. The 32 strains most suited to growth in a fermented meat environment were inoculated in sausage minces together with Pediococcus pentosaceus, incubated at 25 C for I week and the produced aroma compounds collected. The data were analysed by multiple linear regression and partial least squares regression analysis. The results showed that increasing pH and temperature from 4.6 to 6.0 and 10 to 26 C. respectively, increased growth of all strains with strong synergy between temperature and pH. Increasing salt concentration from 5% to 15% w/v decreased growth of most strains, but the effect of pH and temperature was much stronger than the effect of salt. Strains of S. carnosus were more salt tolerant than strains of S. equorum and S, xylosus, especially at high pH and temperature. Addition of glucose up to 0.5% w/v had no significant influence on growth of any of the strains. With regard to aroma production, species characteristics were detected. S. carnosus and S. xylosus were quite different regarding the overall aroma profiles, whereas the profiles of S. equorum lied somewhere in-between. Contrary to S. carnosus, S. xylosus and S. equorum did not produce 2-methyl-1-butanol. On the other hand, in particular, S. xylosus produced more 3-methyl-1-butanol. Except for one of the strains of S. equorum, S. xylosus and S. equorum formed more diacetyl, 2-butanone and acetoin and also more of the methyl-branched ketones arising from degradation of leucine, isoleucine and valine. S. carnosus produced more methyl-branched aldehydes, acids and corresponding esters from leucine, isoleucine and valine-compounds that have been correlated with fermented sausage maturity in former studies. S. equorum produced the least of the methyl-branched aldehydes.

104

Testes sensoriais de aceitação da beterraba vermelha (Beta vulgaris ssp. vulgaris L.), cv. Early Wonder, minimamente processada e irradiada/ Sensory acceptance tests of red beet (Beta vulgaris ssp. vulgaris L.), cv. Early Wonder, minimally processed and irradiated  

Abstract in portuguese A beterraba vermelha (variedade hortícola, cultivar Early Wonder) foi cultivada na área experimental do Departamento de Fitotecnia do Instituto de Agronomia da Universidade Federal Rural do Rio de Janeiro. Após a colheita, as raízes foram minimamente processadas, embaladas e submetidas a diferentes doses de radiação gama (0; 0,5; 1,0; e 1,5 kGy), sendo em seguida armazenadas, por 20 dias, a 8 ºC. Durante o período de armazenamento, aos: 1, 9, 13 e 20 dias, foram r (more) ealizados testes sensoriais, nos quais 12 avaliadores julgaram a aparência e o aroma segundo uma escala hedônica. Os resultados indicaram que as amostras irradiadas com doses de 1,0 e 1,5 kGy mantiveram-se dentro dos padrões de aceitabilidade por 20 dias. Alem disso, foi também observado que a avaliação do aroma permitiu uma melhor discriminação, dos efeitos das diferentes doses de radiação sobre a aceitação do produto. Abstract in english Red beet (Early Wonder) was cultivated in an experimental area of the Department of Fitotecnia at the Institute of Agronomy at the Rural Federal University of Rio de Janeiro (UFRRJ). After harvest, the roots were minimally processed; packed; exposed to different doses of gamma radiation (0; 0.5; 1.0 and 1.5 kGy) and stored for 20 days at 8.0 ºC. Sensory evaluations were performed 1; 9; 13 and 20 days after irradiation by 12 testers who rated the overall appearance and ar (more) oma on a hedonic scale. The results indicated that the irradiated samples remained within the limit of acceptance for 20 days. In addition, the aroma was found to be a more sensitive indicator of the effect of different doses of radiation to the acceptance of the product.

105

A Solanum lycopersicum catechol-O-methyltransferase involved in synthesis of the flavor molecule guaiacol.  

O-methyltransferases (OMT) are important enzymes that are responsible for the synthesis of many small molecules, which include lignin monomers, flavonoids, alkaloids, and aroma compounds. One such compound is guaiacol, a small volatile molecule with a smoky aroma that contributes to tomato flavor. Little information is known about the pathway and regulation of synthesis of guaiacol. One possible route for synthesis is via catechol methylation. We identified a tomato O-methyltransferase (CTOMT1) with homology to a Nicotiana tabacum catechol OMT. CTOMT1 was cloned from Solanum lycopersicum cv. M82 and expressed in Escherichia coli. Recombinant CTOMT1 enzyme preferentially methylated catechol, producing guaiacol. To validate the in vivo function of CTOMT1, gene expression was either decreased or increased in transgenic S. lycopersicum plants. Knockdown of CTOMT1 resulted in significantly reduced fruit guaiacol emissions. CTOMT1 overexpression resulted in slightly increased fruit guaiacol emission, which suggested that catechol availability might limit guaiacol production. To test this hypothesis, wild type (WT) and CTOMT1 that overexpress tomato pericarp discs were supplied with exogenously applied catechol. Guaiacol production increased in both WT and transgenic fruit discs, although to a much greater extent in CTOMT1 overexpressing discs. Finally, we identified S. pennellii introgression lines with increased guaiacol content and higher expression of CTOMT1. These lines also showed a trend toward lower catechol levels. Taken together, we concluded that CTOMT1 is a catechol-O-methyltransferase that produces guaiacol in tomato fruit. PMID:22103597

106

Estudio del Secado de Anacardo (Anacardium occidentale L.) mediante Secador Solar de Radiación Directa/ Cashew-nut (Anacardium occidentale L.) Drying Study Using a Solar Dryer with Direct Radiation  

Abstract in spanish Se presentan ensayos de secado con radiación solar directa y su modelado matemático, para evaluar la cinética de secado del anacardo (Anacardium occidentale L.) y comparar su eficiencia en relación al secado solar natural en tablero. Los experimentos fueron realizados con rodajas de fruta de 1 cm. y 2 cm. de espesor, obteniendo su contenido acuoso versus tiempo. Con el empleo del secador solar de radiación directa, se redujo el tiempo de secado en relación al secado (more) natural en tablero, agregando valor a los productos. Se obtuvo valores de difusividad de agua en rodajas de frutos del mismo orden de otros datos de la literatura. Los productos secados resultaron tener buenas propiedades organolépticas, tales como sabor, aroma, color y textura crocante. Abstract in english In this work solar drying tests with direct radiation and its mathematical modeling to evaluate the kinetics of cashew-nut (Anacardium occidentale L.) drying comparing their efficiency concerned to natural solar drying board are presented. The experiments were performed using fruit slices with 1 cm and 2 cm of thickness, obtaining its water content versus time. Using a direct solar radiation dryer, the drying time was lower than that of natural drying board, therefore add (more) ing value to products. Diffusivity values obtained from water sliced fruits were similar to other data available in the literature. The dried products had good organoleptic properties, aroma, color and crunchy texture.

107

Extraction of bioproducts with homogeneous membranes  

Product recovery (enrichment, purification) is an essential part of the process design and a major cost factor in biotechnological productions. The economic feasibility of bio-productions is influenced by the real effect of recovery costs and by the tacit effect of a growing acceptance of `natural` products, both advocating development of advanced separation methods. Membrane processes using homogeneous (non-porous) membranes are favorably suited to enrich organic minority species from aqueous-organic mixtures at moderate (ambient) temperature and without the use of solvents. The relevant features of the principal membrane processes will be presented as they relate to bio-separations: Pervaporation, pertraction, vapour permeation. Pervaporation is presented in detail, and application to the recovery of flavours and aroma compounds is illustrated by a number of case studies involving esters, lactones, aldehydes and alcohols, and vanillin. Literature results are summarized, also with a view on competing separation methods. (orig.)

108

Customer knowledge management in the natural cosmetics industry  

Purpose - This paper aims to examine the level of customer knowledge (CK) for natural cosmetic products, namely Bulgarian rose products, in three European countries - Bulgaria, Montenegro and Italy - and to propose appropriate solutions for its management. Design/methodology/approach - The research structure is based on a questionnaire and represents a part of the general investigation about the nature of the Bulgarian rose products. The study includes the responses to priority questions on customers' knowledge about these products. Feedback is received from 236 respondents in 450 distributed inquiries for the whole investigation. Findings - The results of the research indicate that the role of the customers in the cognitive process of knowledge accumulation for the specific and rare aroma...

109

Effects of Different Extraction Methods on Aromatic Composition of Essential Oils of Citrus keraji hort. ex Tanaka ‘Kabuchii’  

Citrus keraji hort. ex Tanaka var. kabuchii (‘Kabuchii’) originates from Okinawa, and has been cultivated in the Okinawa Islands for hundreds of years. However, the components responsible for its characteristic fresh aroma have not been determined. ‘Kabuchii’ is used as a table fruit and also in the production of traditional sweets and juice. At present, the residues produced during the manufacturing process are underutilized. In the present study, we extracted the essential oil from ‘Kabuchii’ peel residues using different extraction methods and characterized its aromatic components by gas-chromatography/mass-spectrometry. We identified 70 aromatic components in the essential oil of ‘Kabuchii’, and found that different extraction methods gave oils with a similar composition. Our results suggest that the residues from citrus processing factories could be used for the manufacture of other products, e.g., aromatherapy, food, flavor, and cosmetic products. The results of present study provide data that could be used by the citrus industry to develop new ‘Kabuchii’ products.   

110

Fruit volatile analysis using an electronic nose.  

Numerous and diverse physiological changes occur during fruit ripening, including the development of a specific volatile blend that characterizes fruit aroma. Maturity at harvest is one of the key factors influencing the flavor quality of fruits and vegetables. The validation of robust methods that rapidly assess fruit maturity and aroma quality would allow improved management of advanced breeding programs, production practices and postharvest handling. Over the last three decades, much research has been conducted to develop so-called electronic noses, which are devices able to rapidly detect odors and flavors. Currently there are several commercially available electronic noses able to perform volatile analysis, based on different technologies. The electronic nose used in our work (zNose, EST, Newbury Park, CA, USA), consists of ultra-fast gas chromatography coupled with a surface acoustic wave sensor (UFGC-SAW). This technology has already been tested for its ability to monitor quality of various commodities, including detection of deterioration in apple; ripeness and rot evaluation in mango; aroma profiling of thymus species; C(6) volatile compounds in grape berries; characterization of vegetable oil and detection of adulterants in virgin coconut oil. This system can perform the three major steps of aroma analysis: headspace sampling, separation of volatile compounds, and detection. In about one minute, the output, a chromatogram, is produced and, after a purging cycle, the instrument is ready for further analysis. The results obtained with the zNose can be compared to those of other gas-chromatographic systems by calculation of Kovats Indices (KI). Once the instrument has been tuned with an alkane standard solution, the retention times are automatically converted into KIs. However, slight changes in temperature and flow rate are expected to occur over time, causing retention times to drift. Also, depending on the polarity of the column stationary phase, the reproducibility of KI calculations can vary by several index units. A series of programs and graphical interfaces were therefore developed to compare calculated KIs among samples in a semi-automated fashion. These programs reduce the time required for chromatogram analysis of large data sets and minimize the potential for misinterpretation of the data when chromatograms are not perfectly aligned. We present a method for rapid volatile compound analysis in fruit. Sample preparation, data acquisition and handling procedures are also discussed. PMID:22491160

111

Determinação do perfil sensorial e parâmetros de qualidade de figos em calda produzidos pela indústria brasileira/ Sensory and instrumental evaluation of canned figs manufactured by Brazilian industries  

Abstract in portuguese Onze provadores selecionados e treinados avaliaram a aparência, aroma, sabor e textura de seis diferentes marcas de figo em calda, comercializadas no mercado brasileiro, utilizando o método de Análise Descritiva Quantitativa (ADQ) adaptado. As amostras foram testadas utilizando-se blocos incompletos balanceados e os resultados estatisticamente analisados por Análise de Variância (ANOVA) e Análise de Componente Principal (ACP). Figos em calda provenientes de indústr (more) ias distintas mostraram uma grande diferença quanto ao perfil sensorial. Dos quinze descriptores desenvolvidos pela equipe sensorial, suculência e aroma doce foram os mais importantes para discriminar as amostras entre si. As medidas de cor obtidas através do colorímetro de Hunter mostraram boa relação com as medidas sensoriais, entretanto, as medidas de textura realizadas pelo aparelho Warner-Bratzler não refletiram as variações de textura encontradas nas amostras pela equipe sensorial. A metodologia desenvolvida no presente estudo demonstrou ser bastante eficiente na caracterização e discriminação de amostras, em função de seus perfis sensoriais. Assim, a presente metodologia pode ser muito útil a laboratórios de Controle de Qualidade e Desenvolvimento de Novos Produtos nas indústrias de alimentos. Abstract in english Eleven selected and trained panelists evaluated the appearance, aroma, flavor and texture of six different brands of Brazilian canned figs by adapted Quantitative Descriptive Analysis. A descriptive ballot and reference material illustrating sensory characteristics of the figs were developed. Samples were tested using a incomplete block design and the results analyzed by Analysis of Variance (ANOVA) and Principal Component Analysis (PCA). The samples sensory profiles show (more) ed large differences. From the fifteen descriptors developed by the panel, juiciness and sweet aroma were the most important for discriminating among samples. Instrumental measurements of color, obtained with a Hunter colorimeter, showed good relation with sensory measurements; but the shear force, obtained with a Warner-Bratzler shear instrument, did not related well with sensory measurements of texture. The methodology developed in this study was very efficient for characterizing and discriminating among the samples as a function of their sensory profiles; furthermore, it can be very useful to the Quality Control and Product Development laboratories of food industries.

112

Percepção de consumidores do Rio Grande do Sul em relação a quesitos de qualidade em frutas/ Perception of Rio Grande do Sul consumers about fruit quality questions  

Abstract in portuguese Objetivando identificar os principais quesitos de qualidade na tomada de decisão para adquirir e consumir frutas e suas possíveis inter-relações com faixa etária, sexo, grau de instrução e renda, foi realizada pesquisa com consumidores de frutas do Estado do Rio Grande do Sul. O experimento foi realizado em seis municípios (Porto Alegre, Pelotas, Santa Maria, Caxias do Sul, Passo Fundo e Santa Rosa). O método utilizado foi o descritivo, e os dados foram coletados (more) através de questionário, entrevistando-se 1.040 pessoas. Os quesitos apresentados (variáveis) foram: preço; aparência, sabor e aroma; embalagem; regularidade de oferta (facilidade para encontrar o produto); marca; vida de prateleira (durabilidade); praticidade (fácil de transportar e utilizar); ausência de resíduos de agrotóxicos; origem; certificação; meio ambiente; valor nutricional; valor funcional; valorização de aspectos socioculturais; outros. De acordo com os consumidores, independentemente de idade, sexo, grau de instrução e renda, os atributos preço; aparência, sabor e aroma; ausência de resíduos de agrotóxicos e identificação da origem são, em ordem decrescente, os principais quesitos para a tomada de decisão para comprar ou não uma determinada fruta. Abstract in english To identify the main quality questions considered for decision to acquire and consume fruits and its possible relation with age, sex, instruction and income category, we carried out this research with consumers of fruits in Rio Grande do Sul State. The experiment was carried out in six cities (Porto Alegre, Pelotas, Santa Maria, Caxias do Sul, Passo Fundo and Santa Rosa). The methodology used was descriptive research for statistical method and the data were collected by q (more) uestionnaire, in the form of personal interview with 1040 people. The attributes (variables) questioned were related with the price; appearance, flavor and aroma; packing; regularity of offers (easiness to find the product); mark; shelf life (durability); practical (easy to carry and to use); without residues of pesticides; origin; certification; environment; nutritional value; functional value; valuation of cultural aspects; others. According to the consumers, independent of the age, sex, instruction and income category, price; appearance, flavor and aroma; absence of residues of pesticides and identification of the origin, in decreasing order of importance, are considered the most important attributes at the purchase.

113

Doces de corte formulados com casca de manga/ Sweets formulated with mango skin  

Abstract in portuguese Na industrialização da manga, a casca é um dos componentes de descarte. No entanto, a mesma pode ser utilizada como fonte de nutrientes, na composição de diversos outros produtos. Logo, este estudo teve como objetivo avaliar a qualidade de doces de corte, formulados com 0% (controle), 25%, 50%, 75% e 100% de cascas, em substituição à polpa de manga (Mangifera indica L. cv. Haden). Os critérios de qualidade utilizados foram: umidade, cinzas, proteínas, lipídios, (more) carboidratos totais, açúcares totais, açúcares redutores, açúcares não redutores, pH, acidez total, acidez titulável e em ácido cítrico, sólidos solúveis totais, fibras (totais, solúveis e insolúveis), antioxidantes, características microbiológicas e aceitabilidade sensorial (aparência, aroma, sabor e cor). Nos doces formulados com casca de manga, foram observados teores significativamente maiores de minerais (cinzas), pH, fibra alimentar, sólidos solúveis e sacarose. O incremento de casca de manga, nas formulações, elevou a atividade antioxidante, permitindo sugerir que a casca da manga é uma fonte alternativa de antioxidantes naturais. Os resultados das análises microbiológicas foram satisfatórios para todos os tratamentos, estando dentro dos padrões estabelecidos. No aspecto sensorial, houve boa aceitação, com notas acima de 7, para aparência, sabor, cor e aroma. Portanto, a substituição parcial ou total da polpa por cascas, na formulação de doce de corte de manga Haden é uma alternativa viável, sob os aspectos nutricional, sensorial e microbiológico. Abstract in english Concerning the mango industrial processing, skin is a disposal component. However, it can be used as a nutrient source in many by-products.The objective of this study was to evaluate the quality of sweets formulated with 0% (control), 25%, 50%, 75%, and 100% of mango skin in substitution to the mango (Mangifera indica L. cv. Haden) pulp. The quality features evaluated were: moisture, ashes, proteins, lipids, total carbohydrates, total sugars, reducing and non-reducing sug (more) ars, pH, total acidity, titratable and citric acid acidity, total soluble solids, fibers (total, soluble, and insoluble), antioxidants, microbiological features, and sensorial acceptability (appearance, aroma, flavor, and color). For the sweets formulated with mango skin, significantly higher levels of minerals (ashes), pH, dietary fiber, soluble solids, and sucrose were observed. Furthermore, the increase of mango skin in the formulations also increased the antioxidant activity, what suggests that the mango skin is an alternative source of natural antioxidants. The microbiological analyses results were satisfactory for all treatments, according to established standards. For the sensorial aspect, there was a good consumer acceptance, with notes above 7, for aspect, flavor, color, and aroma. Therefore, the partial or total substitution of the mango pulp by mango skin, for the formulation of Haden mango sweet is a viable alternative, when considered its nutritional, sensorial, and microbiological aspects.

114

Aceitabilidade de biscoitos e bolos à base de arroz com café extrusados/ Acceptability of biscuits and rice and extruded coffee-based cakes  

Abstract in portuguese O objetivo deste trabalho foi avaliar a granulometria de farinha do trigo e de farinhas pré-cozidas por extrusão obtidas da mistura de arroz com pó de café (15 e 20%), bem como a aceitabilidade de biscoitos e bolos elaborados a partir da adição de 20 e 30% da farinha pré-cozida na mistura da massa (trigo). Os resultados obtidos mostraram que as farinhas extrusadas apresentaram maior granulometria que a farinha de trigo; à medida que se aumentou o percentual de far (more) inha pré-cozida na mistura com o trigo, também aumentou a granulometria. Não houve diferença significativa entre as amostras tratadas com 15 e 20% de farinha pré-cozida quanto à preferência sensorial de aroma, textura, sabor e impressão global avaliados em bolos. Entretanto, os biscoitos elaborados com a farinha pré-cozida com 15% de pó de café na mistura com arroz apresentaram maior preferência para aroma e textura ao serem comparados com aqueles com 20%; a farinha pré-cozida de pó de café com arroz pode ser utilizada como ingrediente na mistura de bolos, biscoitos e outros produtos alimentícios em até 30%. Abstract in english The objective of this study was to evaluate the granulometry of wheat flour and flour precooked by extrusion obtained from the mixture of rice and coffee (15 and 20%), as well as the acceptability of biscuits and cakes prepared with 20 and 30% of precooked flour in the mixture of the dough (wheat). The results obtained show that the extruded flours presented thicker granulometry than the wheat flour. Granulometry increased with the increase of the content of precooked flo (more) ur in the mixture with wheat. There were no significant differences among the samples treated with 15 and 20% of precooked flour as to the sensorial preference of aroma, texture, flavor, and global impression. However, the biscuits made with precooked flour with 15% of coffee in the mixture with rice presented greater preference of aroma and texture if compared with those with 20%. It can be said that up to 30% of rice and coffee-based precooked flours can be used as ingredient in the mixture of cakes and biscuits and other food products.

115

A LEXICON FOR TEXTURE AND FLAVOR CHARACTERISTICS OF FRESH AND PROCESSED TOMATOES  

ABSTRACT A lexicon for describing the sensory flavor and texture characteristics of fresh and processed tomatoes was developed. A six-member highly trained, descriptive sensory panel identified, defined and referenced 33 sensory attributes for fresh and processed tomatoes. Forty products including a variety of raw, canned, concentrated and dried tomatoes, as well as tomato-based products including ketchup and simple pasta sauce, were evaluated in the study. These products represented a wide range of sensory characteristics in raw and processed tomatoes. The lexicon established included 5 aroma attributes, 10 texture attributes and 18 flavor attributes including 6 taste and mouthfeel attributes. The lexicon provides attribute descriptors, definitions and references that often are lacking in...

116

Evaluation of fruit productivity and quality in Hass avocado submitted to {sup 60}Co gamma radiation; Evaluacion de productividad y calidad de fruta en aguacate Hass sometido a radiacion gamma de {sup 60}Co  

Evaluation of productivity, postharvest behavior and fruit quality was performed on four years Hass avocado trees irradiated with {sup 60} Co gamma rays in doses of 5, 10, 15, 20 and 25 Gy, established in the ''La Labor'' Experimental Center of the Centro de Investigaciones Cientificas y Tecnologias del Aguacate en el Estado de Mexico (CICTAMEX) at Temascaltepec Mexico. Productivity had a significant increase in the dose of 15 Gy being the average number of fruits nearly 400 % more than the control at fruit setting, being such difference reduced at fruit harvesting to 300 %. In regard to postharvest performance, the respiration index (mg CO{sub 2}/kg/hr) did not show significant differences among treatments. Also others variables such as physiological weight losses, texture, maturity pattern, and sensorial tests (color, flavor, aroma, texture) were not different in regard to the control. This mean that radiation has altered productivity but not the quality and postharvest behavior of fruits. (Author)

117

Apple Pomace: A Versatile Substrate for Biotechnological Applications  

Apple pomace is the processing waste generated after apple juice manufacturing and represents up to 30% of the original fruit. This solid residue consists of a complex mixture of peel, core, seed, calyx, stem, and soft tissue. This residual material is a poor animal feed supplement because of its extremely low protein content and high amount of sugar. The application of agroindustrial by-products in bioprocesses offers a wide range of alternative substrates, thus helping solve pollution problems related to their disposal. Attempts have been made to use apple pomace to generate several value-added products, such as enzymes, single cell protein, aroma compounds, ethanol, organic acids, polysaccharides, and mushrooms. This article reviews recent developments regarding processes and products t...

118

Apple pomace: a versatile substrate for biotechnological applications.  

Apple pomace is the processing waste generated after apple juice manufacturing and represents up to 30% of the original fruit. This solid residue consists of a complex mixture of peel, core, seed, calyx, stem, and soft tissue. This residual material is a poor animal feed supplement because of its extremely low protein content and high amount of sugar. The application of agroindustrial by-products in bioprocesses offers a wide range of alternative substrates, thus helping solve pollution problems related to their disposal. Attempts have been made to use apple pomace to generate several value-added products, such as enzymes, single cell protein, aroma compounds, ethanol, organic acids, polysaccharides, and mushrooms. This article reviews recent developments regarding processes and products that employed apple pomace as a substrate for biotechnological applications. PMID:18322854

119

Procedural Investigations of the Lautering Process  

Beer production begins in the brewhouse, where milled malt is mixed with water. Relevant ingredients of the malt are converted and dissolved into wort. The solids have to be separated from the remaining liquid. This step is done in the lauter tun and is still a very time-consuming process. Additionally, the procedural knowledge of this production step is still rather poor. Another aim in beer production is the evaporation of unwanted aroma compounds. Usually this is done during wort boiling. The latest research showed that the preliminary steps should be done before boiling. The developed system is the result of these two principles, evaporation of unwanted flavoring substances and prevention of blocking of the filter cake. The approach was the integration of a bubble generator in the laut...

120

Non-target screening of Allura Red AC photodegradation products in a beverage through ultra high performance liquid chromatography coupled with hybrid triple quadrupole/linear ion trap mass spectrometry.  

The study deals with the identification of the degradation products formed by simulated sunlight photoirradiation in a commercial beverage that contains Allura Red AC dye. An UHPLC-MS/MS method, that makes use of hybrid triple quadrupole/linear ion trap, was developed. In the identification step the software tool information dependent acquisition (IDA) was used to automatically obtain information about the species present and to build a multiple reaction monitoring (MRM) method with the MS/MS fragmentation pattern of the species considered. The results indicate that the identified degradation products are formed from side-reactions and/or interactions among the dye and other ingredients present in the beverage (ascorbic acid, citric acid, sucrose, aromas, strawberry juice, and extract of chamomile flowers). The presence of aromatic amine or amide functionalities in the chemical structures proposed for the degradation products might suggest potential hazards to consumer health. PMID:23122105

 
 
 
 
121

Formation of volatile sulfur compounds and metabolism of methionine and other sulfur compounds in fermented food  

The formation of volatile sulfur compounds (VSC) in fermented food is a subject of interest. Such compounds are essential for the aroma of many food products like cheeses or fermented beverages, in which they can play an attractive or a repulsive role, depending on their identity and their concentration. VSC essentially arise from common sulfur-bearing precursors, methionine being the most commonly found. In the first section of this paper, the main VSC found in cheese, wine, and beer are reviewed. It is shown that a wide variety of VSC has been evidenced in these food products. Because of their low odor threshold and flavor notes, these compounds impart essential sensorial properties to the final product. In the second section of this review, the main (bio)chemical pathways leading to VSC...

122

Influence of autochthonous starter cultures on microbial dynamics and chemical-physical features of traditional fermented sausages of Basilicata region  

In this study, a combination of a Lactobacillus sakei strain and a Staphylococcus equorum strain was used as autochthonous starter for an experimental production of Basilicata fermented sausages. The influence of starter addition on the safety and quality parameters and microbiological and chemical-physical properties of the products was investigated. Microbial counts of safety indicators were lower in the samples with the addition of starter culture, and, at the end of ripening, Enterobacteriaceae and Gram negative bacteria were detected only in samples made without the starter addition. The addition of starter led to a final product with better microbiological and chemical-physical features, and a positive effect on flavor and aroma compounds formation by a good proteolytic and lipolytic...

123

Prevalence, concentration, spoilage, and mitigation of Alicyclobacillus spp. in tropical and subtropical fruit juice concentrates.  

The presence of Alicyclobacillus in fruit juices and concentrates poses a serious problem for the juice industry. This study was undertaken to determine the (i) prevalence, concentration, and species of Alicyclobacillus in tropical and subtropical concentrates; (ii) efficacy of aqueous chlorine dioxide in reducing Alicyclobacillus spp. spores on tropical and subtropical fruit surfaces; and (iii) fate of and off-flavor production by Alicyclobacillus acidoterrestris in mango and pineapple juices. One hundred and eighty tropical and subtropical juice concentrates were screened for the presence and concentration of Alicyclobacillus spp. If found, the species of Alicyclobacillus was determined by 16S rDNA sequencing and analysis with NCI BLAST. Of these samples, 6.1% were positive for Alicyclobacillus, and nine A. acidoterrestris strains and two Alicyclobacillus acidocaldarius strains were identified. A five-strain cocktail of Alicyclobacillus spp. was inoculated onto the surface of fruits (grapefruit, guava, limes, mangoes, oranges and pineapple), which were then washed with 0, 50, or 100 ppm aqueous chlorine dioxide. Significant reductions due to chlorine dioxide were only seen on citrus fruits. A five-strain cocktail of A. acidoterrestris was inoculated into mango and pineapple juices. Microbial populations were enumerated over a 16-day period. Aroma compounds in the juice were analyzed by GC-olfactometry (GC-O) and confirmed using GC-MS. GC-O of mango juice identified previously reported medicinal/antiseptic compounds. GC-O of pineapple juice revealed an unexpected "cheese" off-aroma associated with 2-methylbutyric acid and 3-methylbutyric acid. PMID:21356453

124

Maintaining the Anthocyanin Content and Improvement of the Aroma of an Alcoholic Fermented Beverage Produced from Raw Purple-Fleshed Sweet Potato  

We have been developing and studying an alcoholic fermented beverage produced from a raw purple-fleshed sweet potato cultivar (Ipomoea babatas cv. Ayamurasaki) containing high amounts of anthocyanin. In this study, we investigated the relationship between the anthocyanin content and aroma of the beverage and its manufacturing process. When raw sweet potatoes were allowed to stand for 1h at 5°C or 30°C between grinding and the initiation of fermentation, the anthocyanin content of the resulting beverage was considerably lower than that of an otherwise identical beverage produced from sweet potatoes ground immediately before fermentation. With that in mind, we investigated the effect of pH on maintenance of the anthocyanin content of ground sweet potato and found that decreasing the pH to 3.0 with citric or lactic acid made it possible to allow the ground sweet potatoes to stand for 3h at 30°C before starting fermentation, without any loss of anthocyanin. Moreover, the addition of citric acid led to the production of large amounts of higher alcohols such as isoamyl alcohol and isobutyl alcohol. These findings suggest that citric acid has desirable effects on both the color and the aroma of the alcoholic fermented beverage produced from raw purple-fleshed sweet potato.   

125

Primary odorants of naturally soiled laundry : Influence of lipase on the odour profile  

Odorants still attached to laundry soiled with human axillary sweat and sebum, after a mild washing procedure, were extracted and analysed by aroma extract dilution analysis. Esters (ethyl-2-methylpropanoate and ethylbutanoate), ketones (1-hexen-3-one and 1-octen-3-one) and, in particular, aldehydes ((Z)-4-heptenal, octanal, (E)-2-octenal, methional, (Z)-2-nonenal, (E,Z)-2,6-nonadienal, (E,Z)-2,4-nonadienal, (E,E)-2,4-decadienal and 4-methoxybenzaldehyde) were identified as primary odorants. Organic acids, which are dominating, characteristic odorants in human axillary sweat, were, on the other hand, effectively removed during wash. The influence of lipase activity on the odour profile was investigated by analysing selected sets of textile swatches, sampled from the right/left axillary of male runners, washed in the presence/absence of lipase. The swatcheswere examined by a sensory ranking analysis prior to the analytical odour analysis. Swatches selected for the subsequent odour analysis possessed greater odour intensity, when washed in the presence of lipase than the corresponding swatches washed in the absence of lipase. The aroma extract dilution analysis revealed that generally the aldehydes were present in slightly higher concentrations in swatches washed in the presence of lipase. Many of the aldehydes identified are well known lipid oxidation products, which are believed to be formed through oxidative degradation of triglycerides present in human sebum - a process that may be facilitated by lipase.

126

Infección por Leuconostoc en pacientes con síndrome de intestino corto, nutrición parenteral y alimentación enteral continua/ Leuconostoc infcctions in patients with short gut syndrome, parenteral nutrition and continuous enteral feeding  

Abstract in spanish Leuconostoc es una cocácea grampositiva parecida a los Streptococcus, que se encuentra ampliamente distribuida en la naturaleza; es usada en la industria de vinos, productos lácteos y quesos para la producción de aromas y texturas. Leuconostoc causa ocasionalmente infecciones en humanos, puede producir bacteriemia, infección asociada a catéter, síndrome séptico, meningitis, neumonía, infección del tracto urinario, osteomielitis y compromiso hepático, entre otros (more) . Se describen como factores de riesgo para una infección por este agente: el síndrome de intestino corto, uso de catéter venoso central y la alimentación enteral por gastrostomía. Orientan a la presencia de este agente el aislamiento de una cocácea grampositiva, catalasa negativa, PYR y LAP negativas, resistente a vancomicina. El tratamiento de elección es penicilina o ampicilina Abstract in english Leuconostoc is a grampositive cocci, quite ubiquitous in nature. It is used in wine industry, and for aroma and texture of dairy products. Occasionally it has been isolated from humans in cases of bacteremia, catheter associated infections, sepsis, meningitis, pneumonia, UTI, osteomyelitis and hepatic dysfunction. Short bowel syndrome, patients with CVC and patients with gastrostomy undergoing enteral feeding, are described amongst the factors associated with this infecti (more) on. The isolation of a grampositive cocci, that does not hydrolyze arginine and that is resistant to vancomycin leads to this diagnostic possibility. Antibiotic treatment: penicillin or ampicillin

127

Evaluation of noni (Morinda citrifolia) volatile profile by dynamic headspace and gas chromatography-mass spectrometry/ Avaliação do perfil de voláteis em noni (Morinda citrifolia) por headspace dinâmico e cromatografia gasosa-espectrometria de massas  

Abstract in portuguese O noni é um fruto que tem interessado à comunidade científica por sua atividade funcional e medicinal. Já se encontram no mercado diferentes produtos que contêm noni em sua composição, mas seu consumo tem sido prejudicado por seu aroma e sabor desagradáveis. O objetivo deste trabalho foi o de avaliar o perfil de voláteis da polpa de noni pela técnica de headspace dinâmico e cromatografia gasosa-espectrometria de massas. Foram detectados 37 compostos voláteis, sendo os principais: alcoóis (63,3%), ésteres (26,9%), cetonas (7,4%) e ácidos (1,2%). Abstract in english Noni is a fruit that has interested the scientific community due to its medicinal and functional activities. Different products that contain noni are already in the market, but their consumption could be impaired by their distinctive unpleasant aroma and flavor. The aim of this work was to evaluate the noni pulp volatile profile by dynamic headspace and gas chromatography-mass spectrometry. Thirty seven volatile compounds were detected, mainly alcohols (63.3%), esters (26.9%), cetones (7.4%), and acids (1.2%).

128

Glucose exerts a negative effect over a peroxidase from Trichosporon asahii, with carotenoid cleaving activity.  

Tobacco aroma compounds were generated via lutein cleavage by the combined action of a yeast and a bacterium identified as Trichosporon asahii and Paenibacillus amylolyticus, respectively. In this study, an inverse relationship between glucose concentration and the generation of three compounds, present in the tobacco aroma profile, was observed in mixed cultures. In order to identify the organism sensitive to the sugar effect, both were grown separately. The presence of glucose suppressed beta-ionone production by T. asahii grown with lutein. However, the biotransformation of the ionone into its reduced derivatives (7,8-dihydro-beta-ionone and 7,8-dihydro-beta-ionol) by P. amylolyticus was not affected by the sugar. This pointed to the cleavage of lutein, a step within the process necessary for the synthesis of beta-ionone, as the target of the glucose effect. In vitro studies with crude extracts and concentrated cell-free medium derived from T. asahii cultures showed that the carotenoid breakdown activity was located extracellularly and only detected in supernatants from yeast cells grown in the absence of the sugar. Rather than an inhibition or a mechanism affecting the enzyme secretion, the glucose effect on lutein degradation comprised another regulatory level. Further experiments showed that the enzyme responsible for lutein breakdown and susceptible to the sugar effect exhibited a high degree of identity to fungal peroxidases, studied as well, for their involvement in carotenoid cleavage. PMID:19390852

129

Avaliação sensorial de sorvetes à base de xilitol/ Sensory evaluation of ice creams prepared with xylitol  

Abstract in portuguese O presente trabalho objetivou relacionar o poder adoçante de solução de xilitol e sacarose, procurando saber se existe diferença de doçura entre sorvetes de nata, morango e chocolate adicionados destes dois adoçantes, em diferentes concentrações, assim como verificar a qualidade sensorial do produto quanto a aparência, cor, aroma, consistência e sabor. Houve diferenças significativas (p (more) nas concentrações de 100% sacarose versus 50% xilitol. Quanto à qualidade dos sorvetes, pode-se observar que o sorvete de nata e suas 3 concentrações de adoçantes foram as formulações que apresentaram maiores diferenças de qualidade, pois dos 5 atributos avaliados, obteve-se diferença significativa (p Abstract in english The aim of this study was to compare the sweetening power of xylitol and sucrose solutions, verifying differences in sweetness among cream, strawberry and chocolate flavoured ice creams sweetened with these two sweeteners, and also determining the sensory quality of the products with respect to appearance, colour, aroma, consistency and flavour. There were significant differences (p (more) 0% sucrose and 50% xylitol. With respect to quality, the cream flavoured ice creams presented the greatest differences in quality among the three concentrations of sweeteners, since of the five attributes evaluated, significant differences (p

130

Comparative metabolic profiling to investigate the contribution of O. oeni MLF starter cultures to red wine composition.  

In this research work we investigated changes in volatile aroma composition associated with four commercial Oenococcus oeni malolactic fermentation (MLF) starter cultures in South African Shiraz and Pinotage red wines. A control wine in which MLF was suppressed was included. The MLF progress was monitored by use of infrared spectroscopy. Gas chromatographic analysis and capillary electrophoresis were used to evaluate the volatile aroma composition and organic acid profiles, respectively. Significant strain-specific variations were observed in the degradation of citric acid and production of lactic acid during MLF. Subsequently, compounds directly and indirectly resulting from citric acid metabolism, namely diacetyl, acetic acid, acetoin, and ethyl lactate, were also affected depending on the bacterial strain used for MLF. Bacterial metabolic activity increased concentrations of the higher alcohols, fatty acids, and total esters, with a larger increase in ethyl esters than in acetate esters. Ethyl lactate, diethyl succinate, ethyl octanoate, ethyl 2-methylpropanoate, and ethyl propionate concentrations were increased by MLF. In contrast, levels of hexyl acetate, isoamyl acetate, 2-phenylethyl acetate, and ethyl acetate were reduced or remained unchanged, depending on the strain and cultivar evaluated. Formation of ethyl butyrate, ethyl propionate, ethyl 2-methylbutryate, and ethyl isovalerate was related to specific bacterial strains used, indicating possible differences in esterase activity. A strain-specific tendency to reduce total aldehyde concentrations was found at the completion of MLF, although further investigation is needed in this regard. This study provided insight into metabolism in O. oeni starter cultures during MLF in red wine. PMID:22120647

131

Flavour chemistry of methylglyoxal and glyoxal.  

Methylglyoxal (MGO) and glyoxal (GO), known as reactive carbonyl species, can be generated endogenously and exogenously (human body and food system). They are attracting increased attention because of their relationship with diabetes and flavour generation. In this review, their characteristics relating to flavour chemistry are discussed. MGO and GO can be detected in food systems by GC and HPLC after derivatization. MGO and GO formed in the Maillard reaction play important roles as precursors of aroma and colour compounds, especially in Strecker degradation, a major flavour generation reaction. When combined with amino acids they undergo Schiff base formation, decarboxylation and ?-aminoketone condensation leading to heterocyclic aroma compounds such as pyrazines, pyrroles and pyridines. They attack amine groups in amino acids, peptides and proteins to form advanced glycation end products (AGEs) and cause carbonyl stress followed by oxidative stress and tissue damage. Therefore, many studies about scavengers of MGO and GO are seen. The influence of these scavengers on flavour generation is also discussed. PMID:22508009

132

A PTR-MS-Based Protocol for Simulating Bread Aroma During Mastication  

The sampling parameters to simulate retronasal aroma during the mastication of white bread has been optimized using a retronasal aroma simulator (RAS) to compare the retronasal bread aroma with the conventional headspace aroma. The volatile composition in breath was compared with that in the effluent from a RAS using proton transfer reaction mass spectrometry, and the optimized RAS parameters were as follows: 2.5 g of bread sample, 250 mL of buffer, 1 L/min of N2 gas stream, 350 rpm of rotating speed, and 38 °C of water jacket temperature. The increased sensitivity and high reproducibility of RAS enabled detailed measurements of flavor release in the mouth during the mastication of bread. The simulated retronasal aroma was compared with the conventional headspace aromas by gas chroma...

133

Antioxidant activity and characterization of volatile extracts of Capsicum annuum L. and Allium spp.  

Plants that are commonly used in kimchi, a traditional Korean fermented food, include Capsicum annuum L. (green pepper), Allium fistulosum L. (Welsh onion), Allium cepa L. (onion) and Allium scorodoprasm L. (garlic), each of which has its own aroma. Aroma extracts of the plants were isolated by steam distillation under reduced pressure (DRP) and liquid-liquid continuous extraction (LLE). The aroma extracts were identified by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). The major aroma compounds of the plant extracts were sulphides, alcohols and heterocyclic compounds. Antioxidant activities of the aroma extracts were evaluated using two different assays. The aroma extracts isolated from green pepper, Welsh onion, onion and garlic inhibited the oxidation of hexa...

134

Aroma barrier properties of sodium caseinate-based films.  

The mass transport of six different aroma compounds (ethyl acetate, ethyl butyrate, ethyl hexanoate, 2-hexanone, 1-hexanol, and cis-3-hexenol) through sodium caseinate-based films with different oleic acid (OA)/beeswax (BW) ratio has been studied. OA is less efficient than BW in reducing aroma permeability, which can be attributed to its greater polarity. Control film (without lipid) and films prepared with 0:100 OA/BW ratio show the lowest permeability. OA involves a decrease in aroma barrier properties of the sodium caseinate-based films due to its plasticization ability. Preferential sorption and diffusion occurs through OA instead of caseinate matrix and/or BW. The efficiency of sodium caseinate-based films to retain or limit aroma compound transfers depend on the affinity of the volatile compound to the films, which relates physicochemical interaction between volatile compound and film. Specific interactions (aroma compound-hydrocolloid and aroma compound-lipid) induce structural changes during mass transfer. PMID:18361517

135

Use of an Immediate Swallow Protocol to Assess Taste and Aroma Integration in fMRI Studies  

Perception of flavor is a complex process involving the integration of taste and aroma. Few functional magnetic resonance imaging (fMRI) studies have assessed the crossmodal interactions which result in flavor perception, and all previous studies have used a retro-nasal aroma delivery with a delayed swallow, which delays retro-nasal aroma release, and thus, alters taste and aroma integration. In this paper, we assess crossmodal interactions in flavor processing using an immediate swallow fMRI paradigm in 13 healthy volunteers. We compare unimodal taste (sucrose) and unimodal retro-nasal aroma stimuli, with a congruent taste and aroma combination (flavor), to assess crossmodal flavor interactions using an immediate swallow paradigm. Subtraction and conjunction analysis methods are described...

136

Free and bound volatile compounds as markers of aromatic typicalness of Moravia Dulce, Rojal and Tortosi red wines  

Rojal, Moravia Dulce and Tortosi are three red minority grape varieties grown in La Mancha region (Spain). In this work, wines from these grape varieties were elaborated across four harvests (2006-2009). The aroma of wines was studied by instrumental and sensory analysis to determine their typicality and quality. Free and glycosidically-bound aroma compounds were isolated by solid phase extraction (SPE) and analysed using gas chromatography-mass spectrometry (GC-MS). GC-MS analysis of wines identified 75, 78 and 80 free aroma compounds and 59, 62 and 62 bound aroma compounds in Moravia Dulce, Rojal and Tortosi wines, respectively. C6 and benzenic compounds were the major components of free varietal aroma. Bound aroma fraction was characterised by a larger concentration of benzenic and C13-...

137

Development of multipurpose aromatic environmental control system. Tamokutekigata kaori kyokyu system (multipurposeter dot aromater dot system) no kaihatsu  

The multipurpose aromatic environmental control system was outlined which is composed of an aroma feeder, perfumes and a controller for aroma intensity. The aroma feeder for a large space which feeds fine aroma droplets through air conditioners or air ducts was provided together with that installed in rooms for a small space, and the controller adopted mainly a schedule control system by computer program. Various aroma systems adaptable to different usages were outlined, the aroma system for enhancing normal environment, that for shifting thermal sensation, that for providing aromatic time signals together with sonic ones, that for providing aromatic alarms together with sonic ones, that for indicating positions in a subway station for example, that for indicating dangerous places or proofing insects with offensive odor, that for controlling bacteria by fungistatic perfumes, and that for inactivating harmful substances such as ozone and chlorine. 5 refs., 9 figs., 2 tabs.

138

Factors Affecting the Production of a BC1F1 Population and Characterization of the BC1F1 Progenies Obtained from the Interspecific Crosses between a Cultivated Tomato and the peruvianum-complex  

The present study was conducted to evaluate the factors (e.g. cultivar (V), wild species line (L), year (Y) and their interaction) affecting the production of a BC1F1 population (cultivar × F1(cultivar × ‘peruvianum-complex’)), a breeding strategy for using many cultivars as pistillate parents for the production of a BC1F1 population and for the segregation of some characteristics such as sweet aroma of leaf, morphological traits and self-incompatibility in the BC1F1 population. Ovule selection and culture method was used for the production of progenies. The interaction between the cultivar and the wild species line (V × L) was found to be significant. Differences in the number of GOFs (Germinated Ovules per Fruit) among 19 tomato cultivars crossed with F1 (cultivar × L. peruvianum LA1554) were significant. Differences in the number of GOFs among wild species lines (as F1 pollen parents) were also significant and much more pronounced than those of the cultivars. Significant variation was observed within-year and affected the interaction (V × Y) which was variable. The present study suggests that the probability of obtaining a stable, consistent average number of GOFs is high for the production of a BC1F1 population if many cultivars are used at a time as seed parents. The segregation of some characteristics in the BC1F1 population was evaluated. Most of the morphological traits resembled those of the wild species parents. Thirty six percent of the BC1F1 population inherited self-compatibility from the L. esculentum parent. A sensory panel composed of 8 members evaluated the leaf aroma of 100 BC1F1 plants (19 cultivars × F1 derivedfrom LA1554) and two BC1F1 plants were found to have the same sweet aroma as the F1 (pollen parent). In the present study a large BC1F1 population with an expected number of plants was obtained. Sensory attributes of some BC1F1 plants suggested that the expected quantitative trait had successfully been introduced into the BC1F1 population.   

139

Non-target screening of Allura Red AC photodegradation products in a beverage through ultra high performance liquid chromatography coupled with hybrid triple quadrupole/linear ion trap mass spectrometry  

The study deals with the identification of the degradation products formed by simulated sunlight photoirradiation in a commercial beverage that contains Allura Red AC dye. An UHPLC-MS/MS method, that makes use of hybrid triple quadrupole/linear ion trap, was developed. In the identification step the software tool information dependent acquisition (IDA) was used to automatically obtain information about the species present and to build a multiple reaction monitoring (MRM) method with the MS/MS fragmentation pattern of the species considered. The results indicate that the identified degradation products are formed from side-reactions and/or interactions among the dye and other ingredients present in the beverage (ascorbic acid, citric acid, sucrose, aromas, strawberry juice, and extract of c...

140

Biosynthesis of ethyl caproate and other short ethyl esters catalyzed by cutinase in organic solvent  

The main objective of this work was to study the enzymatic synthesis of short chain ethyl esters, a group of relevant aroma molecules, by Fusarium solani pisi cutinase in an organic solvent media (iso-octane), and to assess the influence of different parameters on the reaction yield. Cutinase displayed high initial esterification rates in iso-octane, which amounted to 1.15mmolmin-1mg-1 for ethyl butyrate (C4 acid chain) and 1.06mmolmin-1mg-1 for ethyl valerate (C5 acid chain). High product yields, 84% for ethyl butyrate and 96% for ethyl valerate, were observed after 6h of reaction, for an initial equimolar concentration of substrates (0.1M). The highest product yield (97%) was observed for ethyl caproate (C6) synthesis, a compound which is a part of natural apple and pineapple flavour, fo...

 
 
 
 
141

Combination of Real-Value Smell and Metaphor Expression Aids Yeast Detection  

Background Smell provides important information about the quality of food and drink. Most well-known for their expertise in wine tasting, sommeliers sniff out the aroma of wine and describe them using beautiful metaphors. In contrast, electronic noses, devices that mimic our olfactory recognition system, also detect smells using their sensors but describe them using electronic signals. These devices have been used to judge the freshness of food or detect the presence of pathogenic microorganisms. However, unlike information from gas chromatography, it is difficult to compare odour information collected by these devices because they are made for smelling specific smells and their data are relative intensities. Methodology Here, we demonstrate the use of an absolute-value description method using known smell metaphors, and early detection of yeast using the method. Conclusions This technique may help distinguishing microbial-contamination of food products earlier, or improvement of the food-product qualities.

142

Physical-chemical and sensory properties of pulsed electric field and high hydrostatic pressure treated citrus juices  

The consumers have increasing desire towards fresh, long shelf-life and healthy products by consisting favourable sensory properties. As an ambivalent fact appears that the product should meet all these requirements and should be consumable long time. All these demands lead to the importance of the minimal processing methods. The properties of widely common citrus juices (100% orange, - grapefruit, - and tangerine juice) were analyzed by measuring the possible changes in the physical-chemical parameters (pH, Brix^o, electric conductivity, colour) respectively the aroma and acid content. The applied technology was pulsed electric field (in furthers: PEF) treatment with the parameters of 28kV/cm with 50 pulses; respectively high hydrostatic pressure (HHP) technology with the parameter of 600...

143

The solar drying to the testing ground; Le sechage solaire au banc d`essai  

Three family solar drying, three industrial solar drying and three different methods of drying in the open air have been studied. Several parameters have been observed: temperatures in dryers, ambient temperature, wind, period of sunshine, the evolution of weight of dried products, the water content at the end of the drying, the vitamins content at the beginning and at the end of the drying, the aroma, the taste and the colour of the dried products. The results are given in tables. We can retain that: drying in the open air is more problematic that the drying in a machine, the family dryers get the note: `well`, the professional dryers get the notes from medium to excellent ( for the forced circulation model with photovoltaic supply). (N.C.)

144

Study of drying characteristics of large-cardamom  

India is the largest producer of large-cardamom in the world with a 54% share in world production followed by Nepal (33%) and Bhutan (13%). For long-duration storage of cardamom and in order to bring out its aroma, the fresh cardamom capsules (with 80-85% moisture) has to be dried immediately after harvesting to bring down its moisture content to less than 10% (w.b.) through a curing(drying) process. Still a primitive and inefficient (operating efficiency level of about 5-15%) smoking method (using traditional bhatti) is being used for drying of large- cardamom resulting in huge (estimated 20,000 MT/yr) wastage of fuel wood and poor (charred and blackened ) quality product. This paper gives a brief description of efforts made to obtain basic drying parameters of large- cardamom (which is a pre-requisite for dryer design) under different operating conditions. (Author)

145

Photoproduction of quarkonium from soft color exchanges  

The authors discuss photoproduction of quarkonium states in the models of soft color interactions and the generalized area law for color string reinteractions as implemented in the Monte Carlo program AROMA. The physics of heavy quarks offers many probes for a better understanding of the interplay between perturbative and non-perturbative aspects of quantum chromogynamics. One such question is the production mechanisms for quarkonium states for which a complete understanding is not available presently. The color octet model can describe the large direct production of J/{psi}'s and {psi}'s at the Fermilab Tevatron, which is a factor of {approximately}30 above expectations from the color singlet model, but it does not seem to describe the polarization correctly. In addition, it does not seem to be consistent with data from HERA which agrees quite well with the color singlet model.

146

Response Surface Methodology for Meat-like Odorants from Maillard Reaction with Glutathione I: the Optimization Analysis and the General Pathway Exploration  

Abstract:- This study is about reaction condition optimization and exploration of the general pathway of GSH-participating Maillard reaction. Response surface methodology (RSM) is used to define the reaction condition for optimal meat flavor product generation from synthetic oligopeptides via the Maillard reaction. The optimal reaction condition is: (A) temperature: 131.53 C, (B) reaction time: 94.85 min, (C) volume of 0.2M phosphate buffer: 49.61 mL and (D) initial pH of reactants: 4.79. The priority sequence is: A > D > C > B, and the verification score was 9.1. A preliminarily pathway scheme using CAMOLA has been constructed to suggest a reaction mechanism for meat-like aroma product formation. In addition, a 2-pathway and 3-stage formation scheme of the GSH-participating Maillard react...

147

Synthesis of green note aroma compounds by biotransformation of fatty acids using yeast cells coexpressing lipoxygenase and hydroperoxide lyase  

Green notes are substances that characterize the aroma of freshly cut grass, cucumbers, green apples, and foliage. In plants, they are synthesized by conversion of linolenic or linoleic acid via the enzymes lipoxygenase (LOX) and hydroperoxide lyase (HPL) to short-chained aldehydes. Current processes for production of natural green notes rely on plant homogenates as enzyme sources but are limited by low enzyme concentration and low specificity. In an alternative approach, soybean LOX2 and watermelon HPL were overexpressed in Saccharomyces cerevisiae. After optimization of the expression constructs, a yeast strain coexpressing LOX and HPL was applied in whole cell biotransformation experiments. Whereas addition of linolenic acid to growing cultures of this strain yielded no products, we wer...

148

Thermal and structural study of guava (Psidium guajava L) powders obtained by two dehydration methods  

Abstract in english Two food products (powders) were obtained by hot-air drying or lyophilisation methods on the whole guava fruits. The powders were characterised by sensory and thermal analyses (TGA-DSC), infrared spectroscopy (IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Thermal, morphological and structural characterisations showed a similar behaviour for the two solids. TGA-DSC and IR showed the presence of pectin as the main constituent of solids. A semi-crystal (more) line profile was evidenced by XRD, and lamellar/spherical morphologies were observed by SEM. Sensory analyses revealed an aroma highly related to guava. These value-added food products are an alternative to process guava and avoid loss during postharvest handling.

149

History, Global Distribution, and Nutritional Importance of Citrus Fruits  

Abstract:- Although the mysteries of its history and origin remain unsolved, worldwide cultivation and high-demand production for citrus fruit (genus Citrus in family Rutaceae) make it stand high among fruit crops. Growth of the citrus industry, including rapid development of the processing technology of frozen concentrated orange juice after World War II, has greatly expanded with international trade and steadily increased consumption of citrus fruits and their products during the past several decades. Characterized by the distinct aroma and delicious taste, citrus fruits have been recognized as an important food and integrated as part of our daily diet, playing key roles in supplying energy and nutrients and in health promotion. With low protein and very little fat content, citrus fruits...

150

Furan in coffee: pilot studies on formation during roasting and losses during production steps and consumer handling  

The occurrence of furan in some food products has already been known for a few decades, and it has been reconfirmed in more recent investigations that furan is present in a variety of foodstuffs. This list of products includes roasted coffee, which has been shown to generate furan as a result of the heat treatment at roasting which is applied to achieve the desired aroma and flavour profile of a roasted coffee. The objective of this study is to provide data to allow a better understanding of the available data of furan in coffee, the kinetics of furan generated during roasting, and to estimate the reduction of furan levels afterwards due to subsequent processing steps and consumer handling. Finally, the study is meant as a contribution to establish exposure data on the basis of scientific ...

151

Mapping of Saccharomyces cerevisiae metabolites in fermenting wheat straight-dough reveals succinic acid as pH-determining factor.  

Fermenting yeast does not merely cause dough leavening, but also contributes to the bread aroma and might alter dough rheology. Here, the yeast carbon metabolism was mapped during bread straight-dough fermentation. The concentration of most metabolites changed quasi linearly as a function of fermentation time. Ethanol and carbon dioxide concentrations reached up to 60mmol/100g flour. Interestingly, high levels of glycerol (up to 10mmol/100g flour) and succinic acid (up to 1.6mmol/100g flour) were produced during dough fermentation. Further tests showed that, contrary to current belief, the pH decrease in fermenting dough is primarily caused by the production of succinic acid by the yeast instead of carbon dioxide dissolution or bacterial organic acids. Together, our results provide a comprehensive overview of metabolite production during dough fermentation and yield insight into the importance of some of these metabolites for dough properties. PMID:23122062

152

Pilot-scale evaluation the enological traits of a novel, aromatic wine yeast strain obtained by adaptive evolution  

In the competitive context of the wine market, there is a growing interest for novel wine yeast strains that have an overall good fermentation capacity and that contribute favorably to the organoleptic quality of wine. Using an adaptive evolution strategy based on growth on gluconate as sole carbon source, we recently obtained wine yeasts with improved characteristics in laboratory-scale fermentations. The characteristics included enhanced fermentation rate, decreased formation of acetate and greater production of fermentative aroma. We report an evaluation of the potential value of the evolved strain ECA5(TM) for winemaking, by comparing its fermentation performance and metabolite production to those of the parental strain in pilot-scale fermentation trials, with various grape cultivars a...

153

SPME Technique for Analyzing Headspace Volatiles in Fish Miso, a Japanese Fish Meat-Based Fermented Product  

The optimized conditions were evaluated for solid-phase microextraction (SPME) to investigate the headspace volatiles in fish miso, a Japanese fish meat-based fermented product. The influence on the efficiency for microextraction of such parameters as the sample size, isolation time and temperature, sensitivity and selectivity of several SPME fibers of different liquid phases as well as several extraction techniques was evaluated. Suitable reproducibility and sensitivity of SPME were achieved by combining carbowax/divenylbenzene of 65 ?m thickness as the liquid phase of SPME, 3 g of fish miso, 40 °C of isolation temperature and 40 min of isolation time. The headspace volatiles of fish miso prepared from spotted mackerel were analyzed under the optimized conditions. Although several volatiles contributed to fish miso, certain volatile esters might have played the greatest role in imparting the sweet-fruity aroma to the product.   

154

Identification of aroma-active compounds in â?????wonderfulâ?????? pomegranate fruit using solvent-assisted flavour evaporation and headspace solid-phase micro-extraction methods  

During the last few years, there has been a tremendous increase in consumption of pomegranate fruit and juice. Nevertheless, very little is yet known regarding the volatile constituents that determine the unique aroma of pomegranate fruit. We extracted aroma volatiles from fresh â?????Wonderfulâ?????? pomegranate juice using solvent-assisted flavour evaporation (SAFE) and headspace solid-phase micro-extraction (HS-SPME) methods, and applied gas chromatographyâ??????olfactometry (GCâ??????O) (â?????sniffingâ??????) combined with gas chromatographyâ??????mass spectrometry (GCâ??????MS) analysis, in order to identify volatile aroma-active compounds. In addition, we performed stir bar sorptive extraction (SBSE) of pomegranate aroma volatiles, coupled with GCâ??????MS analysis, in order to assi...

155

Research of fragranced air, environmental aroma, to human and its application. Kankyo hoko no koka to sono oyo  

The effect of lemon, jasmine and lavender aroma on people was studied through environmental aroma experiments by 270 subjects in a meeting room for two months. As a result, the high percentage of positive responses was obtained on the sense of air cleanliness and efficiency of meetings, and a statistical significance was, in particular, obtained in the case of lemon as smoking was permitted. It was suggested that aroma had physiological and phychological effect even under conditions where the subjects were not necessarily aware of aroma. The effect of the same three aromas was also studied through experiments by 13 subjects in a VDT room for one month. As a result, the number of keypunch errors decreased in every aroma although punching speeds decreased slightly, and lemon showed a significant difference among three aromas. Based on these experimental results, the aroma generator was developed, and more than 30 environmental aroma systems combined with air conditioning ducts have been installed in Japan. 20 refs., 5 figs., 6 tabs.

156

Aroma characteristics of cocoa tea (Camellia ptilophylla Chang).  

Three types of Cocoa tea, green, oolong, and black, were prepared from fresh young leaves of Camellia ptilophylla. Their aroma characteristics were compared by a sensory evaluation with corresponding traditional tea samples made from C. sinensis. The aroma profile of Cocoa green tea was quite different from that of traditional green tea, but fermented Cocoa oolong tea and black tea showed aroma profiles similar to those of traditional oolong tea and black tea. Cocoa green tea contained vanillin as the most abundant aroma constituent. Almost the same aroma compounds of jasmine lactone, indole and monoterpene alcohols, which are known as important aroma constituents in commercial oolong tea and black tea, were identified as the main aroma compounds in the fermented Cocoa tea types. The composition of these aroma compounds well explained the aroma profile of each Cocoa tea. The monoterpene alcohols seemed to be released during fermented tea manufacture, because seventeen glycosides consisting of the aglycons of terpene alcohols were identified in Cocoa tea leaves, and hydrolytic activity of crude enzymes in the p-nitrophenol glycoside substrate was also detected. PMID:20460717

157

Gas chromatographic-olfactometric aroma profile and quantitative analysis of volatile carbonyls of grilled beef from different finishing feed systems.  

In this study, the important odor impact volatiles generated in the meat of grilled beef loin muscle were characterized. Animals were finished in 4 different diet systems: T?, pasture (a mixture of Medicago sativa, Trifolium repens, and Festuca arundinacea); T?, pasture supplemented with cracked corn grain (offered at 0.6% live weight, LW); T?, pasture supplemented with cracked corn grain (offered at 1.2% LW); and T?, concentrate (pellets with 85% corn and 12.8% sunflower, on a dry-matter basis) plus alfalfa hay (both ad libitum). Aroma compounds were assessed by dynamic headspace-solid phase extraction (DHS-SPE) and gas chromatographic-olfactometric (GC-O) analysis. Most odorants were carbonyl compounds, some of them reaching high GC-O scores, especially 1-octen-3-one, (E)-2-octenal, methional, and hexanal. A specific quantitative analysis of ketones and aldehydes was conducted through their derivatization with o-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine hydrochloride directly on the headspace trap and analyzed by GC-MS, with the purpose of studying the effect of finishing diet systems. From the 23 carbonyl compounds quantified, 2 were especially affected by the diet system; methional was higher in the treatment based on concentrates, whereas (E,E)-2,4-heptadienal was higher in the treatment based only in pastures. The results are discussed considering previous published productive and quality traits. PRACTICAL APPLICATION: The knowledge of how production factors, such as animal feeding, can affect the flavor of meat is of significant interest toward in achieving a high-quality and differentiated product. The development of more specific and efficient methodologies is necessary to analyze meat aroma compounds, which would be used as routine analysis, that is for product authentication. In the future, the use of this analysis would allow producing and designing specific foods according to different markets. PMID:22591324

158

Monitoring of alcoholic fermentation using near infrared and mid infrared spectroscopies combined with electronic nose and electronic tongue  

Graphical abstract: Application of non destructive methods for the monitoring of red wine fermentation in correlation with the evolution of chemical parameters. Highlights: > We monitored time-related changes in red wine fermentation process. > NIR and MIR spectroscopies, electronic nose and tongue were applied. > Data were kinetically modelled to identify critical points during fermentation. > NIR, MIR electronic nose and tongue were able to follow the fermentation process. > The models agreed with the evolution of chemical parameters. - Abstract: Effective fermentation monitoring is a growing need due to the rapid pace of change in the wine industry, which calls for fast methods providing real time information in order to assure the quality of the final product. The objective of this work is to investigate the potential of non-destructive techniques associated with chemometric data analysis, to monitor time-related changes that occur during red wine fermentation. Eight micro-fermentation trials conducted in the Valtellina region (Northern Italy) during the 2009 vintage, were monitored by a FT-NIR and a FT-IR spectrometer and by an electronic nose and tongue. The spectroscopic technique was used to investigate molecular changes, while electronic nose and electronic tongue evaluated the evolution of the aroma and taste profile during the must-wine fermentation. Must-wine samples were also analysed by traditional chemical methods in order to determine sugars (glucose and fructose) consumption and alcohol (ethanol and glycerol) production. Principal Component Analysis was applied to spectral, electronic nose and electronic tongue data, as an exploratory tool, to uncover molecular, aroma and taste modifications during the fermentation process. Furthermore, the chemical data and the PC1 scores from spectral, electronic nose and electronic tongue data were modelled as a function of time to identify critical points during fermentation. The results showed that NIR and MIR spectroscopies are useful to investigate molecular changes involved in wine fermentation while electronic nose and electronic tongue can be applied to detect the evolution of taste and aroma profile. Moreover, as demonstrated through the modeling of NIR, MIR, electronic nose and electronic tongue data, these non destructive methods are suitable for the monitoring of must-wine fermentation giving crucial information about the quality of the final product in agreement with chemical parameters. Although in this study the measurements were carried out in off-line mode, in future these non destructive techniques could be valid and simple tools, able to provide in-time information about the fermentation process and to assure the quality of wine.

159

Isolamento e seleção de microrganismos pectinolíticos a partir de resíduos provenientes de agroindústrias para produção de aromas frutais/ Screening of fruit flavors producing pectinolitic microorganisms isolated from agroindustrial residues  

Abstract in portuguese As pectinases são enzimas produzidas naturalmente por plantas, fungos, leveduras e bactérias. Estes microrganismos podem ser inoculados em meios contendo resíduos agroindustriais utilizados como fonte de carbono para a produção de compostos de maior valor agregado, como enzimas, etanol, proteínas, aminoácidos e compostos de aroma. Vários microrganismos foram isolados e selecionados quanto à produção de enzimas pectinolíticas pelo método da placa, através de (more) zonas claras de degradação de pectina ao redor da colônia. De 104 linhagens testadas, 18 foram selecionadas para fermentarem em meio líquido, contendo pectina para a determinação de atividade de poligalacturonase (PG) e de pectina liase (PMGL), e em meio frutose/extrato de levedura para produção de aromas. As linhagens 2, 9, 20, 39, 70, 74 e 99 apresentaram unidades de atividade de PG superiores a 80 µmol de ácido galacturônico/mL/min, as linhagens 17, 18, 31, 37, 73, 74 e 125 apresentaram unidades de atividade de PMGL superiores a 1000 etamol de produtos insaturados/mL/min e as linhagens 13, 70, 73, 74, 125 e 144 apresentaram os melhores descritores e as maiores intensidades de aromas percebidos por um painel não treinado de provadores. Abstract in english Pectinases are enzymes used in food industries, produced by plants, fungi, yeasts and bacteria. These microorganisms can be inoculated in a medium containing agro-industrial residues from processing agricultural products, used as a carbon source to produce value-added products such as enzymes, ethanol, proteins, amino acids and flavor compounds. Several microorganisms were isolated and selected due to their capacity to produce pectinolytic enzymes in clear halos around co (more) lonies by plate assay. From 104 strains, 18 were inoculated in a medium containing pectin as a carbon source and the pectinolytic activities of polygalacturonase (PG) and pectin lyase (PMGL) were determined. Strains 2, 9, 20, 39, 70, 74, and 99 showed activity units of PG higher than 80 µmol galacturonic acid/mL/minute. Strains 17, 18, 31, 37, 73, 74 and 125 showed activity units of PMGL higher than 1000 etamol unsaturated products/mL/minute. Strains 13, 70, 73, 74, 125 and 144 showed good signs of flavor noticed in the fructose and yeast extract medium and the most intense flavor according to a non-trained board of tasters.

160

Perfil sensorial e aceitação de presuntos crus produzidos por métodos tradicionais e acelerado/ Sensory profile and acceptance of dry-cured hams produced by traditional and accelerated methods  

Abstract in portuguese Existem muitos tipos de presuntos crus com perfis sensoriais particulares, em decorrência de diferentes matérias-primas e técnicas de processamento, que são apreciados por seus sabores e texturas característicos. Este trabalho objetivou caracterizar o perfil sensorial de presuntos crus através da Análise Descritiva Quantitativa e verificar a aceitação dos produtos pelo consumidor. Foram avaliados dois presuntos crus experimentais, produzidos por processo acelerad (more) o (denominados CTC 3,5 e 5,0% devido ao teor inicial de sal adicionado), e quatro produtos comercializados no Brasil, um Serrano espanhol, um Italiano e dois brasileiros (Tipo Serrano e Tipo Parma). Os produtos diferiram pelos seguintes atributos: CTC 3,5% - sabor mais ácido, menor intensidade de sabor de ranço e aroma de ranço, aparência: menor intensidade de cor vermelha e menor intensidade de suculência; CTC 5,0% - mais fibrosidade, menores intensidade e persistência de sabor e maciez; Serrano - maiores aroma de ranço, cor vermelha, intensidade e persistência de sabor e menor sabor salgado; Tipo Serrano - maior sabor de ranço e menor sabor doce; Italiano - maiores sabor salgado e maciez; Tipo Parma - sabor de carne, marmoreado e amarelo da gordura mais intensos. Todos os produtos obtiveram boa aceitação pelo consumidor. O presunto Tipo Serrano foi o mais aceito e o Serrano foi o menos aceito pelos consumidores brasileiros entrevistados. Os produtos CTC foram considerados de boa qualidade, apresentando características típicas de um presunto cru, apesar do curto período de maturação. Abstract in english There are many types of dry cured hams with particular sensorial profiles resulting from different raw materials and processing techniques, which are appreciated by their characteristic flavors and textures. The objectives of this paper are to characterize the sensorial profile of dry cured hams through a Quantitative Descriptive Analysis, and to verify the products acceptance by the consumer. Two experimental dry cured hams, produced through fast processing (called CTC 3 (more) .5% and 5.0% due the initial added salt content), and four products commercialized in Brazil,: a Spanish Serrano, an Italian one, and two Brazilian ones (Serrano type and Parma type) were evaluated. The products differed in terms of the following attributes: CTC 3.5% - the most acid flavored and the lowest intensity of rancid aroma and flavor, redness and juiciness; CTC 5.0% - the highest fibrousness and the lowest intensity and persistence of flavor, and tenderness; Serrano - the highest rancid aroma, redness, intensity and persistence of flavor and the lowest salty flavor; Serrano type - the highest rancid flavor and the lowest sweet flavor; Italian - the highest salty flavor and tenderness; Parma type - the most intense meat flavor, marbling and fat yellowness. All the products were accepted well by the consumer. The Serrano type was the most accepted and Serrano was the lowest accepted by the Brazilian consumers. The CTC products were considered to be good quality, presenting typical characteristics of a dry cured ham, despite the short maturation period.

 
 
 
 
161

Compuestos volátiles responsables del sabor del tomate/ Volatile compounds resposible of tomato flavor  

Abstract in spanish La producción de frutos de tomate (Lycopersicon esculentum Mill.) con sabor agradable está recibiendo atención especial, porque este atributo se ha convertido en uno de los principales parámetros de calidad en la aceptación de frutas y hortalizas. Aquí se analiza cómo los compuestos volátiles influyen significativamente en el sabor del tomate, por ser responsables de su aroma. Los principales compuestos volátiles del tomate involucran a aldehídos, alcoholes, cet (more) onas y ésteres insaturados de cadenas cortas, los cuales son producidos a partir de ácidos grasos, aminoácidos libres y carotenoides. Entre las principales enzimas involucradas se encuentran lipoxigenasa, hidroperoxidoliasa y alcohol deshidrogenasa para la biosíntesis de volátiles a partir de ácidos grasos; además están las enzimas aminotransferasa, descarboxilasa y alcohol deshidrogenasa, relacionadas con la biosíntesis de volátiles derivados de aminoácidos. La composición y concentración de los compuestos volátiles depende de factores genéticos, así como de las condiciones de cultivo y del almacenamiento. El presente manuscrito compila y analiza la información actual referente a la biosíntesis de los volátiles que definen el aroma del tomate, así como sus rutas metabólicas, enzimas y sustratos involucrados; así mismo analiza los principales factores precosecha, cosecha y poscosecha que afectan su biosíntesis. Abstract in english Production of tomato fruits (Lycopersicon esculentum Mill.) with good flavor is receiving special attention since flavor has become a primary quality parameter in the acceptance of fruits and vegetables. In this manuscript we analyze how volatile compounds play a significant role in flavor perception of tomatoes, as they are responsible of their aroma. The most important volatile compounds in tomato include short-chain unsaturated aldehydes, alcohols, ketones and esters w (more) hich are synthesized from free amino acids, fatty acids and carotenoids. Among the main enzymes involved in the biosynthesis of volatiles derived from fatty acids are lipoxygenase, alcohol dehydrogenase and hydroperoxide lyase, while aminotransferase, decarboxylase and alcohol dehydrogenase are involved in the biosynthesis of volatiles derived from amino acids. This manuscript brings together the current information related to tomato volatiles biosynthesis, including metabolic pathways, enzymes and substrates. In addition, the effects of preharvest conditions and postharvest handling on volatile production are also discussed.

162

Chemical and aroma determination of the pulp and seeds of murici (Byrsonima crassifolia L.)  

Abstract in portuguese O murici (Byrsonima crassifolia L., Malpighiaceae) é uma pequena fruta tropical de intenso aroma frutal e semelhante a queijo rançoso. Aplicando a cromatografia gasosa de alta resolução-olfatometria acoplada a espectrometria de massas e usando técnica de diluição de aroma ("Aroma extract dilution analysis"), as substâncias de maior impacto no aroma do murici foram identificadas como sendo: butanoato de etila (frutal, doce), hexanoato de etila (frutal), 1-octeno-3- (more) ol (odor semelhante a cogumelo), ácido butírico (queijo rançoso), ácido hexanóico (pungente, queijo) e 2-feniletanol (floral). A polpa da fruta é principalmente composta por ésteres etílicos, metílicos e feniletílicos, juntamente com ácidos carboxílicos, terpenos, delta-lactonas e algumas substâncias sulfuradas. As sementes, que apresentaram um aroma semelhante ao de óleo rançoso, também lembrando queijo, tem como componentes majoritários os ácidos linoleico, oleico, esteárico e palmítico. Seu aroma foi associado aos ácidos butírico e hexanóico, ambos minoritários. Abstract in english Murici (Byrsonima crassifolia L., Malpighiaceae), a small, tropical fruit, very popular in Brazil, has a strong fruity, rancid cheese aroma. High resolution gas chromatography-olfactometry-mass spectrometry and aroma extract dilution analysis identified the most potent substances in its aroma as ethyl butanoate (fruity, sweet), ethyl hexanoate (fruity), 1-octen-3-ol (mushroom like), butyric acid (rancid, cheese), hexanoic acid (pungent, cheese) and phenylethyl alcohol (fl (more) oral). Its pulp is mainly composed of ethyl, methyl and phenylethyl esters and by carboxylic acids, terpenoids, delta-lactones and some sulfur compounds. Seed analysis also showed a buttery and oily cheese aroma and GC-MS revealed linoleic, oleic, stearic and palmitic acids as foremost components, while the aroma was associated to the butyric and hexanoic acids present in minor amounts.

163

Production of novel varietal hop aromas by supercritical fluid extraction of hop pellets-Part 2: Preparation of single variety floral, citrus, and spicy hop oil essences by density programmed supercritical fluid extraction  

In this study on the production of novel varietal hop aromas by supercritical fluid extraction of hop pellets we aim at fractionated extraction of hop oil essences by density programmed supercritical fluid extraction (SFE) of hop pellets T90 using carbon dioxide. For that purpose, SFE is performed in two steps. In the first step, the most volatile compounds from hop essential oil are isolated by extracting pellets T90 applying a carbon dioxide density of 0.29g/mL (90atm, 50^oC). Subsequent fractionation of the crude extract from this first SFE step via solid phase extraction (SPE) using octadecylsilica and ethanol/water mixtures, results in flavour-active single variety hop oil essence, highly enriched in 'floral' compounds of total hop essential oil. When added to a non-aromatised pilot l...

164

Fresh Squeezed Orange Juice Odor: A Review  

Fresh orange juice is a highly desirable but unstable product. This review examines analytical findings, odor activity, and variations due to cultivar, sampling methods, manner of juicing, plus possible enzymatic and microbial artifacts. Initial attempts to characterize orange juice odor were based on volatile quantitation and overemphasized the importance of high concentration volatiles. Although over 300 volatiles have been reported from GC-MS analytical studies, this review presents 36 consensus aroma active components from GC-olfactometry studies consisting of 14 aldehydes, 7 esters, 5 terpenes, 6 alcohols, and 4 ketones. Most are trace (? g/L) components. (+)-Limonene is an essential component in orange juice odor although its exact function is still uncertain. Total amounts of ...

165

Comprehensive two-dimensional gas chromatography for fingerprint pattern recognition in olive oils produced by two different techniques in Portuguese olive varieties Galega Vulgar, Cobrancosa e Carrasquenha  

For olive oil production a metal hammer-decanter olive processing line was compared to a traditional metal hammer-press line, a discontinuous method which, if properly used, yields high-quality virgin olive oils. Galega, Carrasquenha and Cobrancosa olives (traditional Portuguese varieties) were studied. The analysis of the aroma compounds was performed after headspace-solid phase micro extraction. The analytical results obtained after comprehensive gas chromatography in tandem with time of flight mass spectrometry (GCxGC/ToFMS) for these three different olive oil varieties, from a single year harvest and processed with two different extraction technologies, were compared using statistical image treatment, by means of ImageJ software, for fingerprint recognitions and compared with principal...

166

Modification of the bitterness of caffeine  

Caffeine is the worlds most consumed psychoactive chemical and as such is a valuable commodity to the food and beverage industry. Caffeine also activates the bitter taste system causing a potential problem for manufacturers wanting to develop products containing caffeine. In the present study both oral peripheral and central cognitive strategies were used in an attempt to suppress the bitterness of caffeine. Subjects (n=33) assessed the influence of sodium gluconate (100mM), zinc lactate (5mM), sucrose (125mM and 250mM), milk (0%, 2% and 4% milk fat), and aromas (coffee, chocolate, mocha) on the bitterness of caffeine (1.5, 3 and 4.5mM). The oral peripheral strategies proved most effective at suppressing the bitterness of caffeine: zinc lactate (-71%, ppp

167

RETENTION OF VOLATILE COMPONENTS OF DURIAN FRUIT LEATHER DURING PROCESSING AND STORAGE  

ABSTRACT A study was conducted to identify the volatile constituents of durian (Durio zibethinus Murr.) of clone D24 and to determine the retention of volatile components of durian fruit leather during processing and storage. Thirty-eight volatile compounds were identified in the fresh durian flesh, of which 11 were esters, 10 alcohols, six carboxylic acids, six sulphurous (S) and nitrogenous (N) compounds and five hydrocarbons. Processed durian fruit leather retained most of the aroma components of fresh durian fruit. During storage, the relative proportion of acids in the product increased, esters, alcohols and aldehydes decreased, while hydrocarbons and phenolic and S and N compounds fluctuated. PRACTICAL APPLICATIONS Development of a new fruit leather from durian (Durio zibethinus Murr...

168

Use of microfungi in the treatment of oak chips: possible effects on wine  

Abstract BACKGROUND: Oak barrels are commonly used in the aging of wines and spirits because of their positive effects on the product. In recent years the addition of oak chips has been used to introduce desirable wood aromas and flavours into wines. In this study, oak chips in saline solution or laboratory medium were inoculated with Penicillium purpurogenum, Aureobasidium pullulans, Phialemonium obovatum, Phanerochaete chrysosporium and a combination of Ph. chrysosporium and A. pullulans. After 12 weeks of incubation, oak chips (2 g L 1) were macerated in a red wine for 17 days. Gas chromatography/mass spectrometry and high performance liquid chromatography were used to evaluate 14 compounds, namely furfural, furfuryl alcohol, guaiacol, syringol, cis methyl octalactone, 2 phenylethanol, ...

169

Purification and Characterization of an ?-D-Xylosidase from Candida utilis IFO 0639  

An intracellular ?-D-xylosidase from Candida utilis IFO 0639 was purified to homogeneity trough four chromatographic steps. The molecular mass of the enzyme was estimated to be 92 kDa by SDS-PAGE. The enzyme had an isoelectric point at 5.6, and was most active at pH 6.0 and at around 40°C. Ethanol at an optimal concentration (10%,v/v) stimulated the initial enzyme activity by 57%. D-Xylose, the product of the ?-D-xylosidase, has no effect on the enzyme activity at 300 mM. The ?-D-xylosidase was highly specific to the ?-D-xylopyranoside configuration. The enzyme hydrolyzed ?-1, 4-linked xylo-oligosaccharides with chain lengths from 2 to 5 by releasing xylose from the non-reducing end. It showed no activity against xylan. The enzyme efficiently released monoterpenols from an aroma precursor extracted from Muscat grape juice. The fermentation of Muscat juice coupled with the enzyme addition produced a small increase in the concentration of monoterpenols.   

170

Anthocyanin-rich sweet potato lacto-pickle: production, nutritional and proximate composition  

Summary Anthocyanin pigment-rich sweet potato (SP) cubes were pickled by lactic fermentation by brining the cut and blanched cubes in common salt (NaCl, 2-10%) solution. They were then inoculated with a strain of Lactobacillus plantarum (MTCC 1407) and incubated for 28 days. Treatment with 8-10% brine solution was found to be organoleptically most acceptable. The final product with 8% and 10% brine solutions had a pH (2.5-2.8), titratable acidity (TA) (1.5-1.7 g kg-1), lactic acid (LA) (1.0-1.3 g kg-1), starch (56-58 g kg-1) and anthocyanin content (390 mg kg-1) on fresh weight basis. Sensory evaluation rated the anthocyanin-rich SP lacto-pickle acceptable based on texture, taste, aroma, flavour and after taste. Principal component analyses reduced the eleven original analytical and proxim...

171

Evaluation of Functional Phytochemicals in Destoned Virgin Olive Oil  

Processing destoned olives by means of extracting adjuvants micronised food talc and depolymerising Cytolase 0 enzyme complex have been studied in the present work. This innovative processing technology increased the plant efficiency (amounts of olives processed per hour) by 20%, as well as the nutritional quality of the end product with respect to functional compounds. The oils showed higher contents of biophenols, aromas, and tocopherols. An intense and balanced flavor and a potentially higher stability and endurance to oxidation (shelf-life) was found. Contents of chloroplast pigments (chlorophylls, pheophytins, carotenes, and xanthophylls) appeared to be lower in comparison to conventional processing. The processing aids allowed to increase significantly the oil yields and to reduce th...

172

Stability of citral in protein- and gum arabic-stabilized oil-in-water emulsions  

Citral is a major flavor component of citrus oils that can undergo chemical degradation leading to loss of aroma and formation of off-flavors. Engineering the interface of emulsion droplets with emulsifiers that inhibit chemical reactions could provide a novel technique to stabilize citral. The objective of this study was to determine if citral was more stable in emulsions stabilized with whey protein isolate (WPI) than gum arabic (GA). Degradation of citral was equal to or less in GA- than WPI-stabilized emulsion at pH 3.0 and 7.0. However, formation of the citral oxidation product, p-cymene was greater in the GA- than WPI-stabilized emulsion at pH 3.0 and 7.0. Emulsions stabilized by WPI had a better creaming stability than those stabilized by GA because the protein emulsifier was able t...

173

Chemical and Physical Stability of Protein and Gum Arabic-Stabilized Oil-in-Water Emulsions Containing Limonene  

ABSTRACT: An important flavor component of citrus oils is limonene. Since limonene is lipid soluble, it is often added to foods as an oil-in-water emulsion. However, limonene-containing oil-in-water emulsions are susceptible to both physical instability and oxidative degradation, leading to loss of aroma and formation of off-flavors. Proteins have been found to produce both oxidatively and physically stable emulsions containing triacylglycerols. The objective of this research was to determine if whey protein isolate (WPI) could protect limonene in oil-in-water emulsion droplets more effectively than gum arabic (GA). Limonene degradation and formation of the limonene oxidation products, limonene oxide and carvone, were less in the WPI- than GA-stabilized emulsions at both pHs 3.0 and 7.0. T...

174

High-cell-density fermentation of Saccharomyces cerevisiae for the optimisation of mead production  

Mead is a traditional drink that contains 8%-18% (v/v) of ethanol, resulting from the alcoholic fermentation of diluted honey by yeasts. Mead fermentation is a time-consuming process and the quality of the final product is highly variable. Therefore, the present investigation had two main objectives: first, to determine the adequate inoculum size of two commercial wine-making strains of Saccharomyces cerevisiae for the optimisation of mead fermentation; and second, to determine if an increase in yeast pitching rates in batch fermentations altered the resulting aroma profiles. Minor differences were detected in the growth kinetics between the two strains at the lowest pitching rate. With increasing pitching rates net growth of the strain ICV D47 progressively decreased, whereas for the QA23...

175

Survival of Lactobacillus acidophilus LMGP-21381 in probiotic ice cream and its influence on sensory acceptability  

Probiotic ice cream was produced by incorporating Lactobacillus acidophilus LMGP-21381 in a standard ice cream mix at initial population above 107-cfu/g. The ice cream mix was inoculated with either freeze-dried or activated cultures of L. acidophilus and a control treatment without probiotic was also prepared. The product was assessed for the survival of the probiotic strain during the freezing process and during 45-weeks of storage at -15C and -25C, and also for its sensory characteristics. The results showed that the freezing process caused a significant decrease in the viability of the freeze-dried culture, but no significant change in the viable counts of L. acidophilus was observed during frozen storage. The sensory attributes of aroma, taste and texture obtained high scores in the s...

176

Dietary Tools To Modulate Glycogen Storage in Gilthead Seabream Muscle: Glycerol Supplementation  

The quality and shelf life of fish meat products depend on the skeletal muscle’s energetic state at slaughter, as meat decomposition processes can be exacerbated by energy depletion. In this study, we tested dietary glycerol as a way of replenishing muscle glycogen reserves of farmed gilthead seabream. Two diets were tested in duplicate (n = 42/tank). Results show 5% inclusion of crude glycerol in gilthead seabream diets induces increased muscle glycogen, ATP levels and firmness, with no deleterious effects in terms of growth, proximate composition, fatty acid profile, oxidative state, and organoleptic properties (aroma and color). Proteomic analysis showed a low impact of glycerol-supplementation on muscle metabolism, with most changes probably reflecting increased stress coping capacity in glycerol-fed fish. This suggests inclusion of crude glycerol in gilthead seabream diets (particularly in the finishing phase) seems like a viable strategy to increase glycogen deposition in muscle without negatively impacting fish welfare and quality.

177

Dietary tools to modulate glycogen storage in gilthead seabream muscle: glycerol supplementation.  

The quality and shelf life of fish meat products depend on the skeletal muscle's energetic state at slaughter, as meat decomposition processes can be exacerbated by energy depletion. In this study, we tested dietary glycerol as a way of replenishing muscle glycogen reserves of farmed gilthead seabream. Two diets were tested in duplicate (n = 42/tank). Results show 5% inclusion of crude glycerol in gilthead seabream diets induces increased muscle glycogen, ATP levels and firmness, with no deleterious effects in terms of growth, proximate composition, fatty acid profile, oxidative state, and organoleptic properties (aroma and color). Proteomic analysis showed a low impact of glycerol-supplementation on muscle metabolism, with most changes probably reflecting increased stress coping capacity in glycerol-fed fish. This suggests inclusion of crude glycerol in gilthead seabream diets (particularly in the finishing phase) seems like a viable strategy to increase glycogen deposition in muscle without negatively impacting fish welfare and quality. PMID:22994592

178

Does ethylene degreening affect internal quality of citrus fruit?  

Citrus fruit are non-climacteric. However, exposure to exogenous ethylene, e.g., during ethylene degreening, stimulates various ripening-related processes in the peel tissue, such as destruction of the green chlorophyll pigments and accumulation of orange/yellow carotenoids. Nonetheless, it is not yet known whether exogenous ethylene affects internal ripening processes in citrus flesh. To address this question, we examined the possible effects of ethylene on taste, aroma, perceived flavor, and nutritional quality of various citrus fruit, including 'Navel' oranges, 'Star Ruby' grapefruit and 'Satsuma' mandarins. Exposure to ethylene enhanced peel color break, and respiration and ethylene production rates in all citrus fruit tested. However, ethylene degreening had no effect on juice total s...

179

Derivatographic investigation of hard coals as a raw material for destructive hydrogenation  

Results of derivatography of Donbass and Kuzbass hard coal at a low stage of metamorphism and with a homogeneous petrographic content of about 80 percent are presented. The coal samples differed only in depth of conversion and yield of products from hydrogenation. Characteristics of the starting coals are given, and the experimental conditions are described. Results of derivatography demonstrated that low metamorphic hard coals which hydrogenated well are characterized by the presence of a narrower and more symmetrical maximum, a faster rate of basic decomposition and by less aroma in comparison with poorly hydrogenating coals. Moisture separation during heating of coal which hydrogenates well is less and occurs at lower temperatures than in poorly hydrogenating coals. (13 refs.) (In Russian)

180

Studying the products of low temperature catalytic hydrogenation of Donbass coals  

Composition and properties of the initial products of low temperature (320-360 C at a hydrogen pressure of 100-105 atmospheres) hydrogenation without a vitrinite solvent are studied: of rank D coal using the nonsulfide catalysts, stannic chloride, nickel chloride and palladium chloride and molybdates of ammonia and nickel; of B, G, Zh and K coals in the presence of stannic chloride. The nature of the coal and catalyst influences the initial and mean temperature of hydrogenation, the quantity of hydrogen absorbed, quantity and composition of the gases separated, yield of volatiles, element composition of the hydrogenates and their solubility in alcohol benzene and methylene chloride. On the basis of element analysis and paramagnetic resonance spectra of solutions in methylene chloride the structural parameters of the hydrogenates were calculated: aroma, degree of aromatic exchange, number of aromatic condensed rings, average length of the aliphatic chains, proportion of aromatic and aliphatic chains. (7 refs.) (In Russian)

 
 
 
 
181

Characterization of Flavor Compounds Released During Grinding of Roasted Robusta Coffee Beans  

The characteristic volatile compounds released during the grinding of roasted coffee beans are as attractive for coffee-flavored products as the aroma of fresh-brewed coffee itself. In this study, the volatile compounds released during the grinding of various roasted robusta coffee beans (originating in Vietnam and Indonesia ; roasting degree L26, L23, and L18) were collected by exposing a solid-phase microextraction (SPME) fiber to nitrogen gas discharged from a glass vessel in which the electronic coffee grinder was enclosed. Identification and characterization of the volatile compounds were achieved using gas chromatography/mass spectrometry (GC/MS) and GC/olfactometry (GC/O), and by applying principal component analysis (PCA) to the GC/O results. The variation in volatile compounds released during grinding, based on origin, roasting degree and species, is described and compared with the results of a previous study on the compounds released during grinding of roasted arabica coffees.   

182

Analysis of a Nicotiana tabacum L. genomic region controlling two leaf surface chemistry traits.  

cis-Abienol and sucrose esters are Nicotiana tabacum leaf surface components that likely influence plant resistance to pests. Their breakdown products also contribute to flavor and aroma characteristics of certain tobacco types. Mapping of genes involved in the biosynthesis of these compounds could permit development of molecular-based tools for generating tobacco types with novel cured leaf chemistry profiles. A doubled haploid mapping population segregating for major genes (Abl and BMVSE) affecting the ability to accumulate cis-abienol and sucrose esters was generated and genotyped with a large set of microsatellite markers. The two genes were found to reside on chromosome A of the N. tabacum genome with a distance of 8.2 cM (centimorgans) between them. Seventeen microsatellite markers were also placed on this linkage group, several of which exhibited complete cosegregation with Abl and BMVSE. Results should aid breeding efforts focused on modification of this aspect of tobacco cured leaf chemistry. PMID:20014852

183

Shelf life extension of sliced wheat bread using either an ethanol emitter or an ethanol emitter combined with an oxygen absorber as alternatives to chemical preservatives  

In the present study, the effect of active packaging [ethanol emitter (EE) or ethanol emitter combined with an oxygen absorber (EE + OA)] on shelf life extension of sliced wheat bread stored at 20 ?C was investigated. Bread containing commercial preservatives (WP) and no preservatives (WOP) were taken as controls. Microbiological, physicochemical and sensory changes occurring in the product as a function of treatment and storage time were monitored for 30 days. Counts for yeasts and molds were 5.1, 3.8, 2.0 and 2.0 log cfu/g and for Bacillus cereus 4.7, 2.5, 2.3 and 2.0 log cfu/g for WOP, WP, EE and EE + OA treatments respectively after 30 days of storage. Initial pH 6.3 and 6.4, for WP and WOP samples remained fairly constant irrespective of specific treatment. Aroma quality deterioration...

184

Mapping of Saccharomyces cerevisiae metabolites in fermenting wheat straight-dough reveals succinic acid as pH-determining factor  

Fermenting yeast does not merely cause dough leavening, but also contributes to the bread aroma and might alter dough rheology. Here, the yeast carbon metabolism was mapped during bread straight-dough fermentation. The concentration of most metabolites changed quasi linearly as a function of fermentation time. Ethanol and carbon dioxide concentrations reached up to 60mmol/100g flour. Interestingly, high levels of glycerol (up to 10mmol/100g flour) and succinic acid (up to 1.6mmol/100g flour) were produced during dough fermentation. Further tests showed that, contrary to current belief, the pH decrease in fermenting dough is primarily caused by the production of succinic acid by the yeast instead of carbon dioxide dissolution or bacterial organic acids. Together, our results provide a compr...

185

Aroma characteristics of fermented Korean soybean paste (Doenjang) produced by Bacillus amyloliquefaciens  

Four strains of Bacillus amyloliquefaciens with high proteolytic, fibrinolytic, and angiotensin converting enzyme (ACE) inhibitory activities were used to make Bacillus-koji suitable for the production of functional doenjang. Volatile compounds in Bacillus-koji doenjang were analyzed by headspace-solid phase microextraction-GC-MS (HS-SPME-GC-MS) to compare the aroma profile with those of commercially produced doenjang made with traditional meju and with modified koji. Extraction temperatures for SPME were adjusted to 30 and 90?C. Commercial samples contained significantly more esters than Bacillus-koji doenjang and demonstrated a more complex volatile compound profile. Pentanoic acid, butanoic acid, or 2/3-methyl butanoic acid, known as off-flavor compounds in doenjang, were not detected i...

186

Terpene production in the peel of sweet orange fruits  

Abstract in english Terpenoids constitute the largest and most diverse class of natural products. They are important factors for aroma and flavor, and their synthesis is basically done from two compounds: isopentenyl diphosphate and dimethylallyl diphosphate. Isopentenyl diphosphate is synthesized through two different pathways, one that occurs in the cytoplasm and one in the plastid. With the sequencing of ESTs from citrus, we were able to perform in silico analyses on the pathways that lea (more) d to the synthesis of terpenes as well as on the terpene synthases present in sweet orange. Moreover, expression analysis using real-time qPCR was performed to verify the expression pattern of a terpene synthase in plants. The results show that all the pathways for isopentenyl diphosphate are present in citrus and a high expression of terpene synthases seems to have an important role in the constitution of the essential oils of citrus.

187

Identification of metabolic pathways involved in the biosynthesis of flavor compound 3-methylbutanal from leucine catabolism by Carnobacterium maltaromaticum LMA 28  

Carnobacterium maltaromaticum strains are widely found in food including fish, meat and some dairy products. Producing a malty/chocolate like aroma due to 3-methylbutanal from the catabolism of leucine is a general characteristic of this species. In this study, we investigated metabolic routes responsible for the biosynthesis of this flavor compound from the catabolism of leucine in C. maltaromaticum LMA 28, a strain isolated from mold ripened soft cheese. Depending on the lactic acid bacterium, leucine can be converted into 3-methylbutanal following two possible metabolic pathways: either directly by a-ketoacid decarboxylase (KADC) pathway or indirectly by a-ketoacid dehydrogenase (KADH) pathway. Both KADC (41.0+/-3.0nmol/mg protein/min) and KADH (1.43+/-0.62nmol/mg protein/min) activitie...

188

Soil analysis reveals the presence of an extended mycelial network in a Tuber magnatum truffle-ground  

Abstract Truffles are hypogeous ectomycorrhizal fungi. They belong to the genus Tuber and are currently considered a hot spot in fungal biology due to their ecological and economic relevance. Among all the species, Tuber magnatum is the most appreciated because of its special taste and aroma. The aim of this work was to set up a protocol to detect T. magnatum in soil and to assess its distribution in a natural truffle-ground. We used the b-tubulin gene as a marker to identify T. magnatum in the soil. This gene allowed us to trace the distribution of the fungus over the entire truffle-ground. Tuber magnatum was found, in one case, 100 m from the productive host plant. This study highlights that T. magnatum mycelium is more widespread than can be inferred from the distribution of truffles an...

189

Changes in aroma-related volatiles and gene expression during low temperature storage and subsequent shelf-life of peach fruit  

Melting flesh peach (Prunus persica L. Batsch., cv. Hujingmilu) fruit were harvested and stored at 0, 5, 8^oC for up to 21 d. Data on emission of characteristic aroma-related volatiles, and expression patterns of related genes, including lipoxygenase (LOX), hydroperoxide lyase (HPL), alcohol dehydrogenase (ADH), and alcohol acyltransferase (AAT), were obtained from fruit at the different low temperatures for 7, 14 and 21 d and a subsequent shelf-life for 3 d after each of those storage times. Production of volatiles was markedly influenced by storage temperature and time. In general, fruit at 5^oC were sensitive to chilling injury (CI) and had the lowest levels of volatile compounds, especially fruity note volatiles such as esters and lactones. An electronic nose (e-nose) was used to evalu...

190

OPTIMIZATION OF CHIPOTLE PEPPER SMOKING PROCESS USING RESPONSE SURFACE METHODOLOGY*  

Abstract Effects of smoking time and temperature on optimal chipotle pepper production were evaluated and optimized using the response surface methodology. Batches of red jalapeo peppers were smoked under different temperatures (65.8, 70, 80, 90, 94.1C) and times (0.96, 2, 4.5, 7, 8-h). Afterward, samples were evaluated for moisture, rheological properties and total phenols. Samples were then dried from 80C to between 0.123 and 0.204-kg H2O/kg dry matter and evaluated for rheological properties, texture, rehydration, color and phenols. Phenol content, rehydration ratio, firmness of peppers, and rheological properties and color of puree were affected (P-PRACTICAL APPLICATIONS Chipotle pepper is highly appreciated by consumers because of their aroma and flavor characteristics. Chipotle peppe...

191

Delivery systems for liquid food products  

One of the present challenges of the food industry is to deliver nutrition and health benefits to the consumer while keeping, or improving the taste and aroma impact. Adding active ingredients to liquid food products for fortification is in most cases not possible or not sufficient to achieve the desired goal, due to the fact that many interesting micronutrients are only hardly soluble in aqueous systems and show (i) a limited stability against chemical or physical degradation, (ii) an incompatibility between the active ingredient and the food matrix, or (iii) reveal an uncontrolled release or bioavailability. Therefore, encapsulation systems, also denoted as 'delivery systems', are typically used to solve these formulation problems. The task to find the appropriate delivery system is espe...

192

Investigation of product quality, sensory profile and ultrastructure of breads made from a range of commercial gluten-free flours compared to their wheat counterparts  

Bread is a major staple food consumed daily in all parts of the world. A significant part of the human population cannot tolerate gluten, a storage protein found in wheat, rye and barley, and therefore, products made from alternative cereals are required. During this study, the bread-making potential of seven gluten-free flours, wheat and wholemeal wheat flour was compared. Fermentation potential of the different flours was determined, showing that dough development height of gluten-free and wholemeal wheat samples was lower than for wheat and oat flour. Apart from standard bread quality parameters such as loaf-specific volume and physical crumb texture, also water activity and shelf life have been determined. The shelf life of gluten-free breads was reduced compared to wheat bread. Aroma ...

193

Determination of total safranal by in situ acid hydrolysis in supercritical fluid media: Application to the quality control of commercial saffron.  

A procedure allowing hydrolysis reactions to be conducted in a dynamic supercritical-CO2 medium was developed for quantifying total safranal (viz. free safranal present in the sample+safranal resulting from picrocrocin hydrolysis), which are the main component of the essential oil and responsible for the characteristic aroma of saffron. The proposed method allows total safranal amounts over the ranges 0.05-1.5 mg mL(-1) to be determined. The standard deviation achieved was 2%. This method was applied to the determination of safranal in natural saffron samples. The results obtained were compared with the "safranal value" total index, which is widely used as a quality measure of saffron products. The comparison revealed that the proposed method provides useful information not contained in the safranal value, based on the fact that, some samples with a high "safranal index" contain low concentrations of safranal. The proposed method is very useful for quality control in commercial saffron samples. PMID:17723702

194

Characterisation of volatile and non-volatile metabolites in etiolated leaves of tea (Camellia sinensis) plants in the dark.  

Aroma is an essential factor affecting the quality of tea (Camellia sinensis) products. While changes of volatile compounds during tea manufacturing have been intensively studied, the effect of environmental factors on volatile contents of fresh tea leaves has received less attention. We found that C. sinensis var. Yabukita kept in darkness by shading treatment for 3weeks developed etiolated leaves with significantly increased levels of volatiles, especially volatile phenylpropanoids/benzenoids (VPBs). Upstream metabolites of VPBs, in particular shikimic acid, prephenic acid, and phenylpyruvic acid, showed lower levels in dark treated than in control leaves, whereas the contents of most amino acids including l-phenylalanine, a key precursor of VPBs, were significantly enhanced. In addition, analysis by ultra performance liquid chromatography-time of flight mass spectrometry, capillary electrophoresis-time of flight mass spectrometry, high performance liquid chromatography, and gas chromatography-mass spectrometry indicated that volatile and non-volatile metabolite profiles differed significantly between dark treated and untreated leaves. PMID:22980801

195

Perfil sensorial e aceitabilidade de diferentes formulações de pão de queijo/ Sensorial profile and acceptability of different formulations of bread of cheese  

Abstract in portuguese Pão de queijo é produto tradicionalmente mineiro. Sua produção vem crescendo muito, expandindo-se inclusive para o mercado externo. Entretanto, ainda não existe um padrão de qualidade. No presente estudo, análise descritiva quantitativa foi aplicada para levantar atributos sensoriais que melhor definem modificações na aparência, aroma, sabor e textura quando alguns ingredientes são variados na formulação do pão de queijo. Sete formulações foram avaliadas p (more) or uma equipe de provadores treinados, dezoito atributos sensoriais foram definidos. Após um período de treinamento, os provadores avaliaram as amostras através de delineamento de blocos incompletos balanceados usando escala não estruturada de 9cm. As mesmas foram também avaliadas em relação a aceitabilidade através da escala hedônica de 9 pontos, por 70 consumidores de pães de queijo. Os resultados foram analisados através da ANOVA, seguida pelo teste de Tukey. As amostras apresentaram diferença significativa (p0,05) entre as amostras que se situaram entre os termos hedônicos "gostei ligeiramente" e "gostei muito". Abstract in english Bread cheese is a traditional product of Minas Gerais-Brazil Its production comes growing a lot, expanding besides for the external market. Despite of this expansion, a trading quality standard was not yet developed. In this work, Quantitative Descriptive analysis was applied to select sensory attributes which best define the changes in appearance, aroma, flavour and texture when different ingredients were used. Seven formulations were evaluated by a selected panel and ei (more) ghteen attributes best describing similarities and differences between then were defined. After a training period panellist evaluated the samples in an incomplete block design using a 9 cm unstructured scale. The developed formulations were also appraised in relation to acceptability through the hedonic scale of 9 points, for 70 consumers of cheese breads. ANOVA and Tukey test (p0,05) was observed between the samples.

196

Chemical and physicochemical characteristics changes during passion fruit juice processing/ Alterações das características químicas e físico-químicas durante as etapas de processamento do suco de maracujá  

Abstract in portuguese O maracujá tem sido bastante consumido devido ao seu aroma e acidez acentuados, tendo grande importância também por seus frutos ricos em sais minerais e vitaminas, sobretudo, A e C. É utilizado em uma série de produtos como sorvetes, mousses e principalmente como suco. Porém, o processamento afeta o conteúdo, a atividade e a biodisponibilidade dos componentes bioativos. Investigações dos efeitos do processamento nos constituintes nutricionais nos sucos são escas (more) sos. Frequentemente, somente as perdas de vitamina C são avaliadas. Este trabalho objetivou investigar como as etapas do processamento (formulação/homogeneização e tratamento térmico) de suco de maracujá afetam as propriedades químicas e físico-químicas deste produto. Os resultados deste estudo indicam que as características químicas e físico-químicas são pouco afetadas pelo processamento, apesar de ter sido verificada diminuição dos teores de vitamina C, antocianinas e carotenoides, estando este último, mesmo após a etapa de pasteurização, em elevadas quantidades. Abstract in english Passion fruit is widely consumed due to its pleasant flavour and aroma acidity, and it is considered very important a source of minerals and vitamins. It is used in many products such as ice-cream, mousses and, especially, juices. However, the processing of passion fruit juice may modify the composition and biodisponibility of the bioactive compounds. Investigations of the effects of processing on nutritional components in tropical juices are scarce. Frequently, only loss (more) es of vitamin C are evaluated. The objective of this paper is to investigate how some operations of passion fruit juice processing (formulation/homogeneization/thermal treatment) affect this product's chemical and physicochemical characteristics. The results showed that the chemical and physicochemical characteristics are little affected by the processing although a reduction in vitamin C contents and anthocyanin, large quantities of carotenoids was verified even after the pasteurization stage.

197

Effects of different roasting temperature on flavor and quality of Oolong tea (Tong-Tin Type)  

The change of liquor color, aroma and taste of oolong tea after roasting have close relation with the change of nonvolatile and volatile compounds. Oolong tea roasted at 8WC still preserved its original golden liquor color, brothy taste, and floral aroma, The high concentrations of linalool, linaloo...

198

Aroma helps to preserve information processing resources of the brain in healthy subjects but not in temporal lobe epilepsy.  

PURPOSE: Inhalation of ylang-ylang aroma has been shown to reduce the auditory P300, an event-related potential thought to reflect higher-order processing. Because olfactory function is sometimes disturbed in temporal lobe epilepsy (TLE), the objective of the present study was to determine whether the effect of ylang-ylang aroma on the auditory P300 was impaired in patients with TLE. METHOD: Fourteen subjects with TLE and 14 healthy controls participated in this study. Electroencephalograms were recorded during an auditory oddball task, and ylang-ylang aroma or odorless air was delivered through a mask. RESULTS: We found that the ylang-ylang aroma prolonged the latencies of P300 in both groups. The ylang-ylang aroma significantly reduced the P300 amplitudes of healthy subjects as described previously. However, in TLE patients, the P300 was unaffected by the aroma. CONCLUSION: The current results show that exposure to the ylang-ylang aroma reduced information processing resources in healthy subjects but had limited effects in patients with TLE. We suggest that impaired higher-order olfactory processing in TLE patients may inhibit the effects of the ylang-ylang aroma on the P300. PMID:23141745

199

Rice aroma and flavor: a literature review.  

The aroma and flavor of cooked rice are major criteria for preference among consumers. Small variations in these sensory properties can make rice highly desired or unacceptable to consumers. Human sensory analyses have identified over a dozen different aromas and flavors in rice. Instrumental ana...

200

Branched-chain and aromatic amino acid catabolism into aroma volatiles in Cucumis melo L. fruit  

The unique aroma of melons (Cucumis melo L., Cucurbitaceae) is composed of many volatile compounds biosynthetically derived from fatty-acids, carotenoids, amino-acids as well as terpenes. Incubation of melon fruit cubes with amino- and a-keto acids led to the enhanced formation of aroma compounds be...

 
 
 
 
201

Characterization of the volatile profile of Brazilian Merlot wines through comprehensive two dimensional gas chromatography time-of-flight mass spectrometric detection.  

Wine aroma is an important characteristic and may be related to certain specific parameters, such as raw material and production process. The complexity of Merlot wine aroma was considered suitable for comprehensive two-dimensional gas chromatography (GC×GC), as this technique offers superior performance when compared to one-dimensional gas chromatography (1D-GC). The profile of volatile compounds of Merlot wine was, for the first time, qualitatively analyzed by HS-SPME-GC×GC with a time-of-flight mass spectrometric detector (TOFMS), resulting in 179 compounds tentatively identified by comparison of experimental GC×GC retention indices and mass spectra with literature 1D-GC data and 155 compounds tentatively identified only by mass spectra comparison. A set of GC×GC experimental retention indices was also, for the first time, presented for a specific inverse set of columns. Esters were present in higher number (94), followed by alcohols (80), ketones (29), acids (29), aldehydes (23), terpenes (23), lactones (16), furans (14), sulfur compounds (9), phenols (7), pyrroles (5), C13-norisoprenoids (3), and pyrans (2). GC×GC/TOFMS parameters were improved and optimal conditions were: a polar (polyethylene glycol)/medium polar (50% phenyl 50% dimethyl arylene siloxane) column set, oven temperature offset of 10 °C, 7s as modulation period and 1.4s of hot pulse duration. Co-elutions came up to 138 compounds in 1D and some of them were resolved in 2D. Among the co-eluted compounds, thirty-three volatiles co-eluted in both 1D and 2D and their tentative identification was possible only due to spectral deconvolution. Some compounds that might have important contribution to aroma notes were included in these superimposed peaks. Structurally organized distribution of compounds in the 2D space was observed for esters, aldehydes and ketones, alcohols, thiols, lactones, acids and also inside subgroups, as occurred with esters and alcohols. The Fischer Ratio was useful for establishing the analytes responsible for the main differences between Merlot and non-Merlot wines. Differentiation among Merlot wines and wines of other grape varieties were mainly perceived through the following components: ethyl dodecanoate, 1-hexanol, ethyl nonanoate, ethyl hexanoate, ethyl decanoate, dehydro-2-methyl-3(2H)thiophenone, 3-methyl butanoic acid, ethyl tetradecanoate, methyl octanoate, 1,4 butanediol, and 6-methyloctan-1-ol. PMID:22277184

202

On the use of Bayesian networks to combine raw data from related studies on sensory satiation  

Bayesian networks were used to combine raw datasets from two independently performed but related studies. Both studies investigated sensory satiation by measuring ad libitum intake of a tomato soup model. The Aroma study varied aroma concentration and aroma duration as the explanatory variables, and the Taste study varied salt intensity. To combine the data from the two studies, the Aroma study needed information on salt aspects for all of its observations. Equally, the Taste study needed information on aroma aspects. This information was used to link the two single networks, each representing one study, into a combined network; therefore, it is referred to as structural linking information. The approach taken is seen as an example for the potential benefit and the challenges when combinin...

203

Temporal Aroma Release Profile of Solid and Liquid Droplet Emulsions  

The release kinetics of four model aroma compounds from coarse (d 32?=?1.0??m) and fine (d 32?=?0.25??m) eicosane and hydrogenated palm stearin (HPS) emulsions prepared with either solid or liquid lipid droplets were measured using a model mouth instrument. For both lipids, the release of aroma compounds from emulsions with solid droplets was higher than from emulsions with liquid droplets. This difference was greater for less polar aroma compounds. The release from solid eicosane droplets increased with particle size but no such effect was observed for HPS emulsions, however, the release from solid eicosane was higher than solid HPS. The initial aroma release profile of the solid droplet emulsion matches that of a similar liquid oil emulsion but requires much less added aroma.

204

How composition and process parameters affect volatile active compounds in biopolymer films  

Active edible films based on chitosan and containing an active aroma compound have been investigated. The influence of the composition of the film forming solution (solvent, plasticizers, nanoparticles, emulsifiers and aroma traps) and process parameters (temperature and viscosity) on drying kinetics, water content, colour, aroma compound retention and partition coefficient was studied. Solvent evaporation rate was increased by addition of ethanol. Water evaporation was delayed by glycerol. The aroma retention during film drying was directly related to the water content. The drying temperature had opposite influences according to the composition of the solvent and additives. Increasing temperature from 20 to 100^oC could increase 3 times the retention of aroma compounds. The viscosity of f...

205

Propiedades funcionales de harinas altas en fibra dietética obtenidas de piña, guayaba y guanábana/ Functional properties of starches with high dietetic fiber content obtained from pineapple, guava and soursop/ Propriedades funcionais de farinhas altas em fibra dietética obtidas de abacaxi, goiaba e graviola  

Abstract in portuguese Compararam-se as propriedades funcionais das farinhas de altos conteúdos de fibra (13,65-65,64%) obtidas de graviola, goiaba e abacaxi desidratadas, com uma fibra comercial (Vitacel®) para avaliar seu potencial de uso em alimentos. A absorção de água nas farinhas (457-525%) foi superior ao do produto comercial (425%); no entanto, a capacidade de absorção de óleo das farinhas (156-195%) foi menor em relação ao Vitacel® (286%). As farinhas de graviola e goiaba ap (more) resentaram propriedades emulsificantes, sendo maiores em agua que em NaCl 1M. A farinha de goiaba, por suas propriedades funcionais, pode ser utilizada como saborizante em produtos tais como o yogurt firme; a farinha de abacaxi, por suas propriedades de hidratação e aroma, pode ser recomendada na elaboração de biscoitos; enquanto que a farinha de graviola, pelas propriedades emulsificantes e seu agradável aroma e sabor, poderia ser utilizada na formulação de sorvetes. As propriedades funcionais e o alto conteúdo de fibra que apresentan estas farinhas permitem seu uso como ingrediente na elaboração de sobremesas. Abstract in spanish Se compararon las propiedades funcionales de las harinas de altos contenidos de fibra (13,65-65,64%) obtenidas de guanábana, guayaba y piña deshidratadas, con una fibra comercial (Vitacel®) para evaluar su potencial uso en alimentos. La absorción de agua en las harinas (457-525%) fue superior que en el producto comercial (425%); no obstante, la capacidad de absorción de aceite de las harinas (156-195%) fue menor en relación al Vitacel® (286%). Las harinas de guaná (more) bana y guayaba presentaron propiedades emulsificantes, siendo mayores en agua que en NaCl 1M. La harina de guayaba, dada sus propiedades funcionales, puede ser utilizada como saborizante en productos tales como el yogurt firme; la harina de piña, por sus propiedades de hidratación y aroma, puede ser recomendada en la elaboración de galletas; mientras que la harina de guanábana, por las propiedades emulsificantes y su agradable aroma y sabor, pudiera ser utilizada en la formulación de helados. Las propiedades funcionales y el alto contenido de fibra que presentan estas harinas permiten su uso como ingrediente en la elaboración de postres. Abstract in english The functional properties of dehydrated soursop, guava and pineapple high fiber content (13.65-65.64%) flours were compared with a commercial fiber (Vitacel®) to assess their potential use in foods. The water absorption of fruit flours (457-525%) was higher than in the commercial product (425%) but the oil absorption was lower (156-195%) than Vitacel® (286%). Guava and soursop flours presented properties of emulsifiers, being greater in water than in NaCl 1M. The guava (more) flour, given its functional properties, can be used as a flavoring agent in various products such as firm yogurt; the pineapple flour, for its hydration properties and flavor, can be recommended in the preparation of crackers; and soursop flour, due to its emulsifier properties and pleasant flavor, could be used in making ice cream. The functional properties and the high fiber content of these flours permit their use as ingredients in desserts.

206

Citrus fruits. Part II. Chemistry, technology, and quality evaluation. B. Technology.  

In Part II of this review on citrus fruits, the literature on chemistry, technology, and quality evaluation are critically considered. Sweet oranges, mandarin, grapefruit, lemon, and lime are generally used for processing. The literature on chemical components of citrus fruit which include sugars, polysaccharides, organic acids, nitrogenous constituents and lipids; carotenoids which contribute to color; vitamins and minerals and flavonoids; limonoids, some of which impart bitterness to the juice; and the volatile components which contribute to aroma were reviewed in section A. Chilled and pasteurized juices, juice concentrates, and beverages are the important products manufactured commercially, and to a limited extent powdered citrus juices, canned segments, and marmalades. The literature on the manufacture of these products also as new types of juice and oil extractors; TASTE and other types of evaporators; tank farms to store juice and concentrate in bulk; aseptic filling in bulk containers and retail packs; alternate flexible and rigid containers other than glass and tin; and recovery of volatile flavoring constituents during juice processing are some of the important technological developments in the recent past and have been discussed in this section. Bitterness in citrus juices and its control, composition of cloud, and its stability and changes during storage have been reviewed. Essential oils, pectin, frozen and dried juice sacs, dried pulp and molasses, flavonoids, seed oil, and meal are the important byproducts, the manufacture of which is given in essential details. Generally, consumers judge the product on the basis of its sensory attributes. The quality of finished product is dependent upon the raw materials used and control of processes. In section C, the U.S. Department of Agriculture (USDA) standards for different products, physicochemical and microbiological parameters prescribed as indices of quality of fruit, juice, concentrate, and other products; composition of essential oils; and aroma concentrates are discussed in relation to sensory quality. Analytical methods for compounds affecting quality, and methods for detection of adulteration in different citrus products are briefly reviewed. The importance of sensorily evaluating quality of citrus products to select and develop quality control indices is emphasized. Areas where further research are required are indicated. A comprehensive bibliography is provided to aid further study and research. PMID:6380950

207

Citrus fruits--varieties, chemistry, technology, and quality evaluation. Part II. Chemistry, technology, and quality evaluation. A. Chemistry.  

In Part 2 of this review on citrus fruits, the literature on chemistry, technology, and quality evaluation are critically considered. Sweet oranges, mandarin, grapefruit, lemon, and lime are generally used for processing. The literature on chemical components of citrus fruit which include sugars, polysaccharides, oraganic acids, nitrogenous constituents and lipids; carotenoids which contribute to color; vitamins and minerals, and flavonoids; limonoids, some of which impart bitterness to the juice; and the volatile components which contribute to aroma have been reviewed. Chilled and pasteurized juices, juice concentrates, and beverages are the important products manufactured commercially, and to a limited extent powdered citrus juices, canned segments, and marmalades. The literature on the manufacture of these products also as new types of juice and oil extractors; TASTE and other types of evaporators; tank farms to store juice and concentrate in bulk; aseptic filling in bulk containers and retail packs; alternate flexible and rigid containers other than glass and tin; and recovery of volatile flavoring constituents during juice processing are some of the important technological developments in the recent past and have been discussed. Bitterness in citrus juices and its control, composition of cloud, and its stability and changes during storage have been reviewed. Essential oils, pectin, frozen and dried juice sacs, dried pulp and molasses, flavonoids, seed oil, and meal are the important byproducts, the manufacture of which is given in essential details. Generally, consumers judge the product on the basis of its sensory attributes. The quality of finished product is dependent upon the raw materials used and control of processes. The U.S. Department of Agriculture (USDA) standards for different products, physicochemical and microbiological parameters prescribed as indices of quality of fruit, juice, concentrate, and other products; composition of essential oils; and aroma concentrates are discussed in relation to sensory quality. Analytical methods for compounds affecting quality, and methods for detection of adulteration in different citrus products are briefly reviewed. The importance of sensorily evaluating quality of citrus products to select and develop quality control indices is emphasized. Areas where further research are required are indicated. A comprehensive bibliography is provided to aid further study and research. PMID:6354594

208

Determinação de marcadores de envelhecimento em cachaças/ Determination of aging marks in sugar cane spirits  

Abstract in portuguese O envelhecimento de bebidas em tonéis de madeira é responsável pela melhoria do sabor e do aroma do produto. Embora o carvalho seja a madeira tradicionalmente utilizada para envelhecimento de bebidas, no Brasil é comum o uso de outras madeiras, como o bálsamo, e madeiras regionais utilizadas por pequenos produtores, fazendo com que o tipo de tonel usado para o envelhecimento possa variar muito. Neste trabalho, é apresentado um estudo da concentração de furanos e f (more) enólicos de baixo peso molecular (ácido gálico, 5-hidroximetilfurfural, furfural, ácido vanílico, ácido siríngico, vanilina, siringaldeído, coniferaldeído, sinapaldeído e cumarina), considerados marcadores de envelhecimento, em cachaças oriundas de pequenos produtores das cinco regiões fabricantes de cachaça do Estado do Ceará. Os resultados obtidos foram comparados com cachaças comerciais consideradas produtos de primeira linha, produzidas nos Estados de Pernambuco, Ceará e Minas Gerais, e apresentaram boa concordância. Abstract in english Alcoholic beverages are usually aged in wooden barrels. This technique improves the taste and the aroma of the product. Although oak is the main wood employed to age beverages, other woods as Balm and local woods are largely employed in Brazil, specially by sugar cane spirits small producers. In this work is presented a study of furans and low molecular weight phenolic compounds (gallic acid, 5-hydroxymethylfurufural, furfural, vanillic acid, syringic acid, vanillin, syri (more) ngaldehyde, coniferaldehyde, sinapaldehyde and coumarin), considered as aging markers in aged sugar cane spirits from small producers of Ceará State (Brazil). The obtained results were compared to reference samples of for export sugar cane spirits and presented good agreement.

209

Headspace solid-phase microextraction-gas chromatography--mass spectrometry analysis of the volatile compounds of Evodia species fruits.  

In this study the investigation of the aroma compounds of dried fruits of Evodia rutaecarpa (Juss.) Benth. and E. rutaecarpa (Juss.) Benth. var. officinalis (Dode) Huang (i.e. E. officinalis Dode) (Rutaceae family) was carried out to identify the odorous target components responsible for the characteristic aroma of these valuable natural products. To avoid the traditional and more time-consuming hydrodistillation, the analyses were carried out by means of headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The SPME headspace volatiles were collected using a divinylbenzene-carboxen-polydimethylsiloxane (DVB-CAR-PDMS) fiber. The extraction conditions were optimized using a response surface experimental design to analyze the effect of three factors: extraction temperature, equilibrium time and extraction time. The best response was obtained when the extraction temperature was around 80 degrees C, equilibrium time near 25 min and extraction time close to 18 min. Analyses were performed by GC-MS with a 5% diphenyl-95% dimethyl polysiloxane (30 m x 0.25 mm I.D., film thickness 0.25 microm) capillary column using He as the carrier gas and a programmed temperature run. The main components of the HS-SPME samples of E. rutaecarpa (concentration >3.0%) were limonene (33.79%), beta-elemene (10.78%), linalool (8.15%), myrcene (5.83%), valencene (4.73%), beta-caryophyllene (4.62%), linalyl acetate (4.13%) and alpha-terpineol (3.99%). As for E. officinalis, the major compounds were myrcene (32.79%), limonene (18.36%), beta-caryophyllene (9.92%), trans-beta-ocimene (6.04%), linalool (5.88%), beta-elemene (7.85%) and valencene (4.62%). PMID:16130723

210

Freeze concentration beats the heat  

This paper reports on freeze concentration (FC) which saves energy and money in packaging, shipping, and storing food products. FC---in contrast to existing heat-evaporation processes---retains volatile flavor and aroma compounds in food products so that no additives are required to restore the taste and smell of the original product. In recent tests on orange, grapefruit, and pineapple juices, reconstituted FC juices were found to be superior in taste to juices produced by evaporation and similar to the original pasteurized juices. The dairy industry, which is the largest user of energy for concentration in the food sector, is looking to FC for new products such as frozen concentrated milk as well as better use of the milk by-products of cheese production. The biggest potential for new FC applications is in those industries that consume large amounts of energy for separation processing, according to a 1987 report prepared for EPRI. In the food industry, this includes milk, vinegar, and beer producers. Potential applications also abound in the pulp and paper, pharmaceutical, chemical, and petroleum industries. FC separates substances via crystallization at substantial energy savings.

211

Report on the survey in fiscal 1998. Basic survey on promotion of joint implementation (scrap and build of Atyrau Refinery in the Republic of Kazakhstan); 1998 nendo chosa hokokusho. Kyodo jisshi nado suishin kiso chosa (Kazakhstan kyowakoku Atyrau seiyusho no scrap and built)  

Discussions were given on the modification plan for Atyrau Refinery in Kazakhstan as a basic survey on promotion of joint implementation based on the COP3. The plan is intended mainly on modernization of overaged refineries, energy conservation, and prevention of pollution. The gists of the plan consist of improvement of quality of diesel oil and gasoline, reduction of production ratio of fuel heavy oil, plant efficiency enhancement, and environmental improvement. The crude oil selected in consideration of the demand in market was the light-gravity Tengiz crude oil whose production increase was attempted. For product quality, a plan was established to modify the facilities to realize improvement in content of light oil, sulfur and aroma, production of non-leaded gasoline, and octane value improvement in consideration of exporting the product into European markets. Since this project is applied to a private corporation, it is necessary that the project is commercially viable. However, the commercially low profitability makes the implementation of the project difficult unless such conditions as crude oil price and product sales price would be improved largely. Effect of the carbon dioxide gas reduction as a result of the implementation would be 180,000 tons annually, but in terms of cost effect, the implementation requires an investment of 500 Dollars per ton of carbon dioxide, thus the effect is low. Reduction in other greenhouse effect gas is not large quantitatively. (NEDO)

212

Marketing de banana: preferências do consumidor quanto aos atributos de qualidade dos frutos/ Marketing of banana: consumer preferences relating to fruit quality attributes  

Abstract in portuguese O Brasil produz aproximadamente seis milhões de toneladas por ano de banana (Musa spp.), com consumo médio da ordem de 35 kg/ habitante / ano. A aceitação da banana deve-se, principalmente, a seus aspectos sensoriais, valor nutricional e conveniência. A identificação das necessidades e desejos dos clientes consiste em uma atividade crítica do marketing. O objetivo deste trabalho foi o de pesquisar as preferências do consumidor de um mercado local (município de C (more) ruz das Almas - Estado da Bahia) considerando os atributos de qualidade dos frutos frescos de banana madura. A metodologia utilizada foi a da pesquisa descritiva por método estatístico. Os dados foram coletados por questionário, na forma de entrevista pessoal com 400 pessoas. Os atributos de qualidade (variáveis) questionados e avaliados foram relacionados com a aparência, cor, textura, aroma, sabor e vida útil esperada dos frutos de banana. De acordo com a preferência dos consumidores entrevistados, o fruto de banana maduro ideal deve apresentar características como: penca contendo 10 a 12 dedos (frutos), dedos de tamanho médio ou grande, diâmetro médio, quina presente, ausência de pintas pretas na casca, cor da polpa amarelo-clara ou média, textura firme, aroma e sabor de intensidade média, mediamente doce e vida útil de 7 a 10 dias em condição ambiente. O sabor, vida útil e aparência dos frutos de banana são considerados os mais importantes atributos na escolha ou compra da banana, segundo os consumidores entrevistados. Abstract in english Brazil has an approximate production of six million annual tons of banana (Musa spp.), with a consumption close to 35 kg / inhabitant / year. The acceptance of the banana fruit is due, mainly, to its sensorial aspects, nutritional value and convenience. The identification of the customers' needs and desires consists of a critical activity of the marketing. The objective of this work was to research the consumer preferences of a local market (Cruz das Almas town, Bahia Sta (more) te) considering the fruit quality attributes of fresh mature banana. The methodology used was descriptive research for statistical method. The data were collected by questionnaire, in the form of personal interview with 400 people. The quality attributes (variables) questioned and appraised were related with the appearance, color, texture, aroma, flavor and shelf-life of the banana fruits. In agreement with the consumers' preference, the fruit of ideal mature banana should present characteristics like hand contends 10 to 12 fingers (fruits), fingers of medium or big size, medium diameter, present angularity, absence of black spots in the peel, color of the pulp light or medium yellow, firm texture, aroma and flavor of medium intensity, medium sweet and shelf-useful of 7 to 10 days in natural conditions. The flavor, shelf-life and appearance of the banana fruits are considered the most important attributes at the purchase, according the consumers.

213

Potencial de multiplicação in vitro de cultivares de morangueiro/ In vitro multiplication potential of strawberry cultivars  

Abstract in portuguese Este trabalho foi realizado com o objetivo de avaliar o potencial de multiplicação in vitro de dez cultivares de morangueiro: Aromas, Bürkley, Camarosa, Campinas, Dover, Milsei-Tudla, Oso Grande, Santa Clara, Sweet Charlie e Vila Nova. Utilizou-se protocolo similar ao dos laboratórios comerciais. A desinfestação dos estolões foi realizada em soluções à base de álcool e hipoclorito de sódio; a cultura dos meristemas em meio semi-sólido MS com 1 mg L-1 BAP, 0,0 (more) 1 mg L-1 ANA e 0,1 mg L-1 AG3; e a multiplicação em meio MS com 1 mg L-1 BAP, à 25 ± 4ºC, 20 µE m-2 s-1 e fotoperíodo de 16 horas. Partiu-se de 10 meristemas de cada cultivar, avaliando-se a taxa de multiplicação e os níveis de contaminação, vitrificação e oxidação durante as fases de estabelecimento (30 dias) e de multiplicação (quatro subcultivos). O número estimado de plântulas obtidas por meristema foi: 559 de 'Aromas'; 569 de 'Bürkley'; 516 de 'Camarosa'; 517 de 'Campinas'; 3.907 de 'Dover'; 1.841 de 'Milsei-Tudla'; 943 de 'Oso Grande'; 350 de 'Santa Clara'; 298 de 'Sweet Charlie', e 1.132 de 'Vila Nova'. A quantificação dessa variabilidade genética é importante para o planejamento da produção de matrizes de cada cultivar nos laboratórios de micropropagação. Abstract in english The objective of this research work was to evaluate the in vitro multiplication potential of ten strawberry cultivars : 'Aromas', 'Bürkley', 'Camarosa', 'Campinas', 'Dover', 'Milsei-Tudla', 'Oso Grande', 'Santa Clara', 'Sweet Charlie', and 'Vila Nova'. The procedures used for this purpose were similar to those found in the protocol observed by commercial micropropagation laboratories. The disinfestation of the scions was made by dipping them in an alcohol and sodium hypo (more) chlorite solution, the meristem culturing in a semisolid medium containing 1 mg of BAP, 0.01 mg of NAA, and 0.1 mg of G3A per liter and the scions multiplication in an MS medium containing 1 mg of BAP at 25° ± 4° C, 20 µE m-2 s-1 and a photoperiod of 16 hours. Each cultivar was represented by 10 scions and for each one the multiplication rate, the levels of contamination, the vitrification and the oxidation were evaluated during the establishment ( 30 days ) and multiplication phases ( 4 subcultures). The estimated number of seedlings per scion from each cultivar was : 559 for 'Aromas', 569 for 'Burkley', 516 for 'Camarosa', 517 for 'Campinas', 3,907 for 'Dover', 1,841 for 'Milsei-Tudla', 943 for 'Oso Grande', 350 for 'Santa Clara', 298 for 'Sweet Charlie', and 1,132 for 'Vila Nova'. The quantification of this genetic variability helps in the planning of the matrical plants production of each cultivar which takes place in commercial micropropagation laboratories.

214

Perfil sensorial de bolos de chocolate formulados com farinha de yacon (Smallanthus sonchifolius)/ Sensorial profile of chocolate cakes formulated with yacon flour (Smallanthus sonchifolius)  

Abstract in portuguese Neste trabalho foi avaliado o uso de farinha de yacon na formulação de bolos de chocolate para se verificar a influência deste constituinte sobre a qualidade sensorial e cromaticidade do produto. Foram analisadas amostras de bolos, formulados com farinha de yacon, denominadas: amostra P (bolo padrão, sem farinha de yacon), amostra A (bolo com 20% de farinha de yacon) e amostra B (bolo com 40% de farinha de yacon). Para a avaliação sensorial, foi realizada a Análise (more) Descritiva Quantitativa (ADQ), utilizando 15 provadores treinados, os quais definiram 9 atributos sensoriais (cor, estrutura do miolo, aroma, gosto doce, sabor de chocolate, sabor residual, umectância, maciez e qualidade global). A análise física dos bolos foi realizada através da caracterização cromática. Os dados sensoriais foram submetidos à análise de variância ANOVA, sendo realizado o teste de Duncan para comparação entre as médias de Duncan, ao nível de 5% de significância. Para verificar as correlações entre as amostras e os atributos, foi realizada a Análise de Componentes Principais (ACP). Na ACP, a soma de componentes principais 1 e 2 foi de 83,3%, ou seja, a variabilidade entre as amostras foi explicada por estes dois componentes. Os resultados obtidos demonstraram que a adição de 40% de farinha de yacon resultou em maiores notas para o aroma (10,16), gosto doce (7,60), sabor de chocolate (10,52), maciez (11,44) e qualidade global (11,64). Com relação ao atributo estrutura não houve diferença significativa entre as notas dos bolos P, A e B. Independente da quantidade de farinha de yacon adicionada, o perfil sensorial dos bolos de chocolate foi influenciado e, em particular, o bolo com maior teor de farinha de yacon apresentou as melhores notas. Abstract in english This study evaluated the use of yacon flour in the formulation of chocolate cakes by investigating its influence on the sensory quality and chromaticity of the product. The following samples were prepared and analyzed: sample P (standard cake without yacon flour), sample A (20% of yacon flour), and sample B (40% of yacon flour). The Quantitative Descriptive Analysis (QDA) was used for the sensory analysis with 15 trained panelists who evaluated 9 sensory attributes (color (more) , crumb structure, aroma, sweet taste, chocolate flavor, residual taste, humectancy, tenderness, and overall quality). The physical analysis of the cake was made by color characterization. The data were subjected to sensory analysis of variance ANOVA and the Duncan's test for comparison between the averages, at 5% level of significance. To verify the correlations between the samples and attributes, the Principal Components Analysis (PCA) was performed. In the PCA, the sum of the principal components 1 and 2 was 83.3%, i.e., the variability between the samples was explained by these two components. The results showed that the addition of 40% of yacon flour resulted in higher scores for aroma (10.16), sweet taste (7.60), chocolate flavor (10.52), tenderness (11.44), and overall quality (11.64). With regard to the attribute crumb structure, there was no significant difference between the scores of cakes P, A, and B. Regardless of the amount of yacon flour added, the sensory profile of the chocolate cakes was influenced. Particularly, the cake with the highest content of yacon flour was attributed the highest scores.

215

Utilization of concentrated cheese whey for the production of protein concentrate fuel alcohol and alcoholic beverages  

The objective of this investigation was to recover the major components of whey and to develop food applications for their incorporation/conversion into acceptable products of commercial value. Reconstituted dried sweet whey with 36% solids was ultrafiltered to yield a protein concentrate (WPC) and a permeate containing 24% lactose and 3.7% ash. Orange juice fortified up to 2.07% and chocolate milks fortified up to 5.88% total protein levels with WPC containing 45% total protein were acceptable to about 90% of a panel of 24 individuals. Fermentation of demineralized permeate at 30/sup 0/C with Kluyveromyces fragilis NRRL Y 2415 adapted to 24% lactose levels, led to 13.7% (v/v) ethanol in the medium at the end of 34 hours. Batch productivity was 3.2 gms. ethanol per liter per hour and conversion efficiency was 84.26% of the theoretical maximum. Alcoholic fermentation of permeate and subsequent distillation produced compounds with desirable aroma characters in such products. This study suggests that there is potential for the production of protein fortified non-alcoholic products and alcoholic beverages of commercial value from whey, thus providing a cost effective solution to the whey utilization problem.

216

Preliminary engineering data for scale up of a biomass vacuum pyrolysis reactor  

The thermal decomposition of wood into charcoal and tar is an old process. One example of the existing technology for wood carbonization is the Lambiotte process. The ATOCHEM plant located in Premery, France, is based on the principle of external gas circulation and is a completely continuous process. The heating gas moves upward in the retort and constantly releases its heat into the wood, which is moving downward. The annual wood charcoal production of this plant is nowadays 20,000 t. The charcoal finds its use in the barbecue and the iron industries. Another example is the Brazilian beehive kiln for charcoal production in a batch mode. In Brazil, charcoal is mainly sold to the iron, the cement and the barbecue industries. In 1986, the total annual production of wood charcoal in Brazil was 7.5 x 10/sup 6/ t. The recovery of by-products is important for the economy of both processes. The French recover high-value chemicals such as food aromas from the pyroligneous liquors. The Brazilians market the wood tar by-product as a bunker fuel oil. However, further studies are still needed and are being conducted by the industry in order to make a greater and a better use of the tar and oil fraction.

217

Contribution of non-volatile and aroma fractions to in-mouth sensory properties of red wines: wine reconstitution strategies and sensory sorting task.  

This work explores to what extent the aroma or the non-volatile fractions of red wines are responsible for the overall flavor differences perceived in-mouth. For this purpose, 14 samples (4 commercial and 10 reconstituted wines), were sorted by a panel of 30 trained assessors according to their sensory in-mouth similarities. Reconstituted wines were prepared by adding the same volatile fraction (coming from a red wine) to the non-volatile fraction of 10 different red wines showing large differences in perceived astringency. Sorting was performed under three different conditions: (a) no aroma perception: nose-close condition (NA), (b) retronasal aroma perception only (RA), and (c) allowing retro- and involuntary orthonasal aroma perception (ROA). Similarity estimates were derived from the sorting and submitted to multidimensional scaling (MDS) followed by hierarchical cluster analysis (HCA). Results have clearly shown that, globally, aroma perception is not the major driver of the in-mouth sensory perception of red wine, which is undoubtedly primarily driven by the perception of astringency and by the chemical compounds causing it, particularly protein precipitable proanthocyanidins (PAs). However, aroma perception plays a significant role on the perception of sweetness and bitterness. The impact of aroma seems to be more important whenever astringency, total polyphenols and protein precipitable PAs levels are smaller. Results also indicate that when a red-black fruit odor nuance is clearly perceived in conditions in which orthonasal odor perception is allowed, a strong reduction in astringency takes place. Such red-black fruit odor nuance seems to be the result of a specific aroma release pattern as a consequence of the interaction between aroma compounds and the non-volatile matrix. PMID:22688035

218

Ingredientes usados na indústria de chocolates/ Ingredients used in chocolate industry  

Abstract in portuguese Chocolate é um produto comumente consumido, sendo que sua produção tem aumentado nos últimos anos. Produzir chocolates requer um entendimento do consumidor. Os tipos preferidos de chocolate variam em cada país. Os diferentes sabores e usos para o chocolate refletem a história da indústria dos diferentes lugares. O sabor do chocolate é parcialmente determinado pela química do produto. O sabor depende da liberação dos compostos aromáticos, enquanto que a textura (more) é uma função da maneira como o material se funde e quebra na boca. Muitos chocolates disponíveis no mercado são elaborados com ingredientes similares, porém apresentam diferentes sabores. Alguns produtores têm aromas específicos, sendo que existem trocas freqüentes nestes devido a variações no processo, acidez e temperatura, ocasionando variações de aroma e sabor no produto final. Por esta razão, as condições de produção do chocolate são mantidas freqüentemente em segredo. Os ingredientes utilizados na produção de chocolates e de seus produtos têm importante papel na aceitação pelo consumidor e na apresentação do produto. Abstract in english Chocolate is a product widely consumed throughout the world that has seen generally increasing production trends over the last years. Making chocolate requires an understanding of how the consumer perceives it. The preferred type of chocolate varies from country to country. The different tastes and uses for chocolate reflect the histories of the industry in different places. The taste of chocolate is partially determined by the chemistry of the product. Taste depends on t (more) he release of flavor compounds in the mouth and nose, while perceived texture is a function of the way in which the material melts and breaks up in the mouth. Most chocolates that are available on the market throughout the world are made from very similar ingredients, yet have very different flavors. Some manufacturers have specific house flavors, and very often this is due to specific changes during the manufacturing process, where changes in holding times, acidity and temperature can give rise to very different flavors in the final chocolate. For this reason, chocolate manufacturing conditions are often kept a closely guarded secret. The ingredients used in chocolate and confectionery products have an important role in consumers acceptance and presentation of the product.

219

Diacetyl levels and volatile profiles of commercial starter distillates and selected dairy foods.  

Starter distillates (SDL) are used as ingredients in the formulation of many food products such as cottage cheese, margarine, vegetable oil spreads, processed cheese, and sour cream to increase the levels of naturally occurring buttery aroma associated with fermentation. This buttery aroma results, in part, from the presence of the vicinal dicarbonyl, diacetyl, which imparts a high level of buttery flavor notes and is a key component of SDL. Diacetyl (2,3-butanedione) is a volatile product of citrate metabolism produced by certain bacteria, including Lactococcus lactis ssp. diacetylactis and Leuconostoc citrovorum. In the United States, SDL are regarded as generally recognized as safe ingredients, whereby usage in food products is limited by good manufacturing practices. Recently, diacetyl has been implicated as a causative agent in certain lung ailments in plant workers; however, little is published about the volatile composition of SDL and the levels of diacetyl or other flavoring components in finished dairy products. The objective of this work was to characterize the volatile compounds of commercial SDL and to quantitate levels of diacetyl and other Flavor and Extract Manufacturers Association-designated high-priority flavoring components found in 18 SDL samples and 24 selected dairy products. Headspace volatiles were assessed using a solid-phase microextraction and analyzed by gas chromatography-mass spectrometry. In addition to diacetyl (ranging from 1.2 to 22,000 ?g/g), 40 compounds including 8 organic acids, 4 alcohols, 3 aldehydes, 7 esters, 3 furans, 10 ketones, 2 lactones, 2 sulfur-containing compounds, and 1 terpene were detected in the SDL. A total of 22 food samples were found to contain diacetyl ranging from 4.5 to 2,700 ?g/100g. Other volatile compounds, including acetaldehyde, acetic acid, acetoin, benzaldehyde, butyric acid, formic acid, furfural, 2,3-heptanedione, 2,3-pentanedione, and propanoic acid, were also identified and quantified in SDL or food samples, or both. The results obtained in this work summarize the volatile composition of commercial SDL and the approximate levels of diacetyl and other Flavor and Extract Manufacturers Association-designated high-priority flavoring components found in SDL and selected dairy foods. PMID:22365196

220

Yeast genes involved in sulfur and nitrogen metabolism affect the production of volatile thiols from Sauvignon Blanc musts.  

Two volatile thiols, 3-mercaptohexan-1-ol (3MH), and 3-mercaptohexyl-acetate (3MHA), reminiscent of grapefruit and passion fruit respectively, are critical varietal aroma compounds in Sauvignon Blanc (SB) wines. These aromatic thiols are not present in the grape juice but are synthesized and released by the yeast during alcoholic fermentation. Single deletion mutants of 67 candidate genes in a laboratory strain of Saccharomyces cerevisiae were screened using gas chromatography mass spectrometry for their thiol production after fermentation of SB grape juice. None of the deletions abolished production of the two volatile thiols. However, deletion of 17 genes caused increases or decreases in production by as much as twofold. These 17 genes, mostly related to sulfur and nitrogen metabolism in yeast, may act by altering the regulation of the pathway(s) of thiol production or altering substrate supply. Deleting subsets of these genes in a wine yeast strain gave similar results to the laboratory strain for sulfur pathway genes but showed strain differences for genes involved in nitrogen metabolism. The addition of two nitrogen sources, urea and di-ammonium phosphate, as well as two sulfur compounds, cysteine and S-ethyl-L: -cysteine, increased 3MH and 3MHA concentrations in the final wines. Collectively these results suggest that sulfur and nitrogen metabolism are important in regulating the synthesis of 3MH and 3MHA during yeast fermentation of grape juice. PMID:22684328

 
 
 
 
221

The microbiology of cocoa fermentation and its role in chocolate quality.  

The first stage of chocolate production consists of a natural, seven-day microbial fermentation of the pectinaceous pulp surrounding beans of the tree Theobroma cacao. There is a microbial succession of a wide range of yeasts, lactic-acid, and acetic-acid bacteria during which high temperatures of up to 50 degrees C and microbial products, such as ethanol, lactic acid, and acetic acid, kill the beans and cause production of flavor precursors. Over-fermentation leads to a rise in bacilli and filamentous fungi that can cause off-flavors. The physiological roles of the predominant micro-organisms are now reasonably well understood and the crucial importance of a well-ordered microbial succession in cocoa aroma has been established. It has been possible to use a synthetic microbial cocktail inoculum of just 5 species, including members of the 3 principal groups, to mimic the natural fermentation process and yield good quality chocolate. Reduction of the amount of pectin by physical or mechanical means can also lead to an improved fermentation in reduced time and the juice can be used as a high-value byproduct. To improve the quality of the processed beans, more research is needed on pectinase production by yeasts, better depulping, fermenter design, and the use of starter cultures. PMID:15462126

222

Kefir Immobilized on Corn Grains as Biocatalyst for Lactic Acid Fermentation and Sourdough Bread Making.  

? The natural mixed culture kefir was immobilized on boiled corn grains to produce an efficient biocatalyst for lactic acid fermentation with direct applications in food production, such as sourdough bread making. The immobilized biocatalyst was initially evaluated for its efficiency for lactic acid production by fermentation of cheese whey at various temperatures. The immobilized cells increased the fermentation rate and enhanced lactic acid production compared to free kefir cells. Maximum lactic acid yield (68.8 g/100 g) and lactic acid productivity (12.6 g/L per day) were obtained during fermentation by immobilized cells at 37 °C. The immobilized biocatalyst was then assessed as culture for sourdough bread making. The produced sourdough breads had satisfactory specific loaf volumes and good sensory characteristics. Specifically, bread made by addition of 60% w/w sourdough containing kefir immobilized on corn was more resistant regarding mould spoilage (appearance during the 11(th) day), probably due to higher lactic acid produced (2.86 g/Kg of bread) compared to the control samples. The sourdough breads made with the immobilized biocatalyst had aroma profiles similar to that of the control samples as shown by headspace SPME GC-MS analysis. PMID:23170776

223

Characterization of Aroma Compounds in Chinese Bayberry (Myrica rubra Sieb. et Zucc.) by Gas Chromatography Mass Spectrometry (GC-MS) and Olfactometry (GC-O)  

Abstract:- The aroma-active compounds in Chinese bayberry were identified using gas chromatography-olfactometry (GC-O) and GC-mass spectrometry techniques. The volatile compounds were extracted using Liquid-liquid extraction, solvent-assisted flavor evaporation and headspace solid-phase microextraction (HS-SPME), respectively. On the basis of odor intensity, the most important aroma compounds in Chinese bayberry samples were caryophyllene, menthol, 4-terpineol, linalool oxide, linalool, benzyl alcohol, -methylbenzyl alcohol, -phenylethanol, 3-methylbutanoic acid and acetic acid, and so on. Moreover, HS-SPME technique was employed to investigate the aroma compounds among immature and mature waxberry fruits. The results showed that terpenes (for example, -caryophyllene) was predominant and i...

224

Aroma components at various stages of litchi juice processing  

BACKGROUND: Considering the importance of flavour on the quality of litchi juice, a study was conducted on how processing and operating stages influence the aroma components of clear litchi juice during processing. RESULTS: The aroma fractions isolated by solid-phase micro-extraction were analysed by capillary gas chromatography-mass spectrometry. According to statistical analyses, the amount of total and seven characteristic aroma compounds (geraniol, citronellol, phenylethyl alcohol, D-limonene, nonanal, geranial and linalool) increased significantly after enzyme hydrolysis, but decreased significantly during the process of enzyme inactivation, ultra-filtration and sterilisation. CONCLUSION: The aromatic fraction of litchi juice decreased greatly during processing. The major losses in ar...

225

Actividad fermentativa de Hanseniaspora uvarum y su importancia en la producción de bebidas fermentadas/ Fermentative activity of Hanseniaspora uvarum and its importance in production of fermented beverages  

Abstract in spanish Se estudió la actividad fermentativa de Hanseniaspora uvarum RIVE 6-2-2 con el objetivo de evaluar su importancia en los procesos de producción de bebidas fermentadas. La cepa se cultivó en frascos Erlenmeyer conteniendo jugo de manzana esterilizado y sin aroma, y se determinaron los compuestos químicos de importancia sensorial producidos durante la fermentación en cultivo agitado (200 min-1) y estático (sin agitación). Los resultados mostraron que la cepa fue capa (more) z de producir etanol hasta 4,02±0,1v/v% en cultivo estático a 28 °C. La agitación del medio de cultivo incrementó la producción de alcoholes superiores (hasta 488,2 mg/L) y ácido acético (468,0±10,2 mg/L) comparado al cultivo estático, mientras que por el contrario, la producción de etil acetato y glicerol (189,0±12,0 mg/L y 3,2±0,3 g/L) resultó ser mayor que en cultivo agitado (142,0±8,0 mg/L y 2,3±0,25 g/L) respectivamente. Cultivos bacth realizados adicionalmente reportaron una tasa de crecimiento (?) de 0,05 h-1 y producción de pequeñas cantidades de compuestos típicamente encontrados en la fermentación alcohólica. Los mejores resultados, en términos de calidad organoléptica (aroma, sabor y olor), se obtuvieron en la fermentación en cultivo estático. El control de la aireación del medio de fermentación es una herramienta importante para controlar la síntesis de compuestos de importancia sensorial en la producción de bebidas fermentadas. Abstract in english The fermentation activity of Hanseniaspora uvarum RIVE 6-2-2 was studied with the purpose of evaluating its importance in the production process of fermented beverages. The strain was cultured in Erlenmeyer flasks, which contained sterilized and odorless apple juice, and the chemical compounds of sensorial importance produced during fermentation in shaken (200 min-1), and static (without shaking) cultures at 28 ºC were determined. The results showed that the strains were (more) capable of producing ethanol up to 4.20±0.1v/v% in static cultures at 28 ºC. Shaking of the culture medium increased the superior alcohol production (up to 488.2 mg/L) and acetic acid (468.0± 10.2 mg/L), when compared with the static culture; on the other hand, the production of ethyl acetate and glycerol (189.0±12.0 mg/L and 3.2±0.3 g/L) was higher in static than in shaken cultures (142.0±8.0 mg/L and 2.3±0.25 g/L), respectively. Additional batch cultures reported a growth rate (µ) of 0.05 h-1 and production of small amounts of compounds typically found in alcoholic fermentation. The best results, in terms of organoleptic qualities (aroma, taste and smell), were found in the static culture fermentation. The aeration control of the fermentation medium is an important tool for controlling the synthesis of sensorial importance compounds in the production of fermented beverages.

226

The fruit ripening-related gene FaAAT2 encodes an acyl transferase involved in strawberry aroma biogenesis.  

Short-chain esters contribute to the blend of volatiles that define the strawberry aroma. The last step in their biosynthesis involves an alcohol acyltransferase that catalyses the esterification of an acyl moiety of acyl-CoA with an alcohol. This study identified a novel strawberry alcohol acyltransferase gene (FaAAT2) whose expression pattern during fruit receptacle growth and ripening is in accordance with the production of esters throughout strawberry fruit ripening. The full-length FaAAT2 cDNA was cloned and expressed in Escherichia coli and its activity was analysed with acyl-CoA and alcohol substrates. The semi-purified FaAAT2 enzyme had activity with C1-C8 straight-chain alcohols and aromatic alcohols in the presence of acetyl-CoA. Cinnamyl alcohol was the most efficient acyl acceptor. When FaAAT2 expression was transiently downregulated in the fruit receptacle by agroinfiltration, the volatile ester production was significantly reduced in strawberry fruit. The results suggest that FaAAT2 plays a significant role in the production of esters that contribute to the final strawberry fruit flavour. PMID:22563120

227

CYP264B1 from Sorangium cellulosum So ce56: a fascinating norisoprenoid and sesquiterpene hydroxylase.  

Many terpenes and terpenoid compounds are known as bioactive substances with desirable fragrance and medicinal activities. Modification of such compounds to yield new derivatives with desired properties is particularly attractive. Cytochrome P450 monooxygenases are potential enzymes for these reactions due to their capability of performing different reactions on a variety of substrates. We report here the characterization of CYP264B1 from Sorangium cellulosum So ce56 as a novel sesquiterpene hydroxylase. CYP264B1 was able to convert various sesquiterpenes including nootkatone and norisoprenoids (?-ionone and ?-ionone). Nootkatone, an important grapefruit aromatic sesquiterpenoid, was hydroxylated mainly at position C-13. The product has been shown to have the highest antiproliferative activity compared with other nootkatone derivatives. In addition, CYP264B1 was found to hydroxylate ?- and ?-ionone, important aroma compounds of floral scents, regioselectively at position C-3. The products, 3-hydroxy-?-ionone and 13-hydroxy-nootkatone, were confirmed by (1)H and (13)C NMR. The kinetics of the product formation was analyzed by high-performance liquid chromatography, and the K ( m ) and k (cat) values were calculated. The results of docking ?-/?-ionone and nootkatone into a homology model of CYP264B1 revealed insights into the structural basis of these selective hydroxylations. PMID:22223101

228

Identification of lactic acid bacteria associated with traditional cachaça fermentations  

Abstract in english During the production of traditional cachaça (alembic´s cachaça), contamination of the fermented must is one of the factors leading to economic losses in the beverage manufacturing industry. The diversity of bacterial populations and the role of these microorganisms during the cachaça production process are still poorly understood in Brazil. In our work, the fermentation process was followed in two distilleries located in the state of Minas Gerais. The objective (more) of this work was to identify the populations of lactic acid bacteria present during cachaça fermentation using physiological and molecular methods. Lactic acid bacteria were isolated in high frequencies during all of the fermentative processes, and Lactobacillus plantarum and L. casei were the most prevalent species. Other lactic acid bacteria were found in minor frequencies, such as L. ferintoshensis, L. fermentum, L. jensenii, L. murinus, Lactococcus lactis, Enterococcus sp. and Weissella confusa. These bacteria could contribute to the increase of volatile acidity levels or to the production of compounds that could influence the taste and aroma of the beverage.

229

Controlled biosynthesis of odd-chain fuels and chemicals via engineered modular metabolic pathways.  

Microbial systems are being increasingly developed as production hosts for a wide variety of chemical compounds. Broader adoption of microbial synthesis is hampered by a limited number of high-yielding natural pathways for molecules with the desired physical properties, as well as the difficulty in functionally assembling complex biosynthetic pathways in heterologous hosts. Here, we address both of these challenges by reporting the adaptation of the butanol biosynthetic pathway for the synthesis of odd-chain molecules and the development of a complementary modular toolkit to facilitate pathway construction, characterization, and optimization in engineered Escherichia coli. The modular feature of our pathway enables multientry and multiexit biosynthesis of various odd-chain compounds at high efficiency. By varying combinations of the pathway and toolkit enzymes, we demonstrate controlled production of propionate, trans-2-pentenoate, valerate, and pentanol, compounds with applications that include biofuels, antibiotics, biopolymers, and aroma chemicals. Importantly, and in contrast to a previously used method to identify limitations in heterologous amorphadiene production, our bypass strategy was effective even without the presence of freely membrane-diffusible substrates. This approach should prove useful for optimization of other pathways that use CoA-derivatized intermediates, including fatty acid ?-oxidation and the mevalonate pathway for isoprenoid synthesis. PMID:23071297

230

Genetic characterization and phenotypic variability in Torulaspora delbrueckii species: Potential applications in the wine industry.  

In this study, several strains of Torulaspora delbrueckii yeast species were evaluated in the laboratory for their enological properties. In a preliminary step, the ability of different molecular methods to discriminate among T.delbrueckii strains was compared. A combination of 7 PCR methods was able to separate 21 strains into 18 groups, while an REA-PFGE method allowed, in one experiment, the separation into 19 groups. The T.delbrueckii strains used presented a wide phenotypic variability in fermentation behaviour, e.g. Lag Phase (LP) duration, T50 parameter (time necessary to ferment half the sugar), and ethanol production. These 3 parameters have to be considered for industrial selection, particularly the LP duration. The majority of T.delbrueckii strains produced 8 to 11% and 7 to 10% ethanol vol. at 17 degrees C and 24 degrees C, respectively, with a maximum ethanol concentration of 12.35 at 17 degrees C and 10.90% vol. at 24 degrees C. The phenotypic variability of this species was also reflected in volatile acidity, glycerol, and aroma production. These experiments confirmed the low volatile acidity and glycerol production of this species and revealed a difference in osmotic stress response, compared to Saccharomyces cerevisiae. T.delbrueckii presented high fermentation purity and produced low levels of undesirable volatile compounds, such as hydrogen sulphide and volatile phenols. PMID:19619911

231

The Fermentative and Aromatic Ability of Kloeckera and Hanseniaspora Yeasts  

Spontaneous alcoholic fermentation from grape, agave and others musts into an alcoholic beverage is usually characterized by the presence of several non-Saccharomyces yeasts. These genera yeasts are dominant in the early stages of the alcoholic fermentation. However the genera Hanseniaspora and Kloeckera may survive at a significant level during fermentation and can influence the chemical composition of the beverage. Several strains belonging to the species Kloeckera api-culata and Hanseniaspora guilliermondii have been extensively studied in relation to the formation of some metabolic compounds affecting the bouquet of the final product. Indeed some apiculate yeast showed positive oenological properties and their use in the alcoholic fermentations has been suggested to enhance the aroma and flavor profiles. The non- Saccharomyces yeasts have the capability to produce and secrete enzymes in the medium, such as ? -glucosidases, which release monoterpenes derived from their glycosylated form. These compounds contribute to the higher fruit-like characteristic of final product. This chapter reviews metabolic activity of Kloeckera and Hanseniaspora yeasts in several aspects: fermentative capability, aromatic compounds production and transformation of aromatic precursor present in the must, also covers the molecular methods for identifying of the yeast

232

Impacto da secagem com microondas sobre o perfil sensorial de amêndoas de noz macadâmia/ Impact of microwave drying on the sensory profile of macadamia nuts  

Abstract in portuguese Avaliou-se o impacto da secagem com microondas sobre o perfil sensorial de noz macadâmia e comparou-se ao perfil sensorial de noz macadâmia seca convencionalmente, através da realização de análise descritiva quantitativa. O estudo ainda compreendeu a análise da alteração desses perfis após seis meses de armazenamento. Foram utilizadas sete amostras de noz macadâmia secas com microondas e uma seca convencionalmente. Os testes conduzidos após o processamento ind (more) icaram que a amêndoa seca convencionalmente apresentou maior gosto de ranço. Para os demais atributos, os tratamentos que utilizaram microondas não diferiram significativamente, em geral, do convencional. As amostras submetidas a microondas não apresentaram diferença estatística entre si, exceto para o atributo aroma de noz. Após seis meses foram observados resultados semelhantes aos encontrados no tempo inicial. Quanto à alteração do perfil sensorial das amostras observou-se perda de intensidade dos atributos sensoriais relativos à textura e intensificação dos atributos relativos à percepção do ranço. Foi possível concluir que, do ponto de vista sensorial, o uso de microondas é viável, pois conduziu a produto semelhante ao convencional. A utilização desta forma de energia conduziu a menores tempos de secagem proporcionando menor impacto, principalmente, na rancificação da noz quando comparado ao produto convencional. Abstract in english The impact caused by microwave drying on the sensory profile of macadamia nuts as opposed to the effects of the conventional drying process was evaluated by means of a quantitative descriptive analysis. Modifications of the sensory profile after a six-month storage period were also analyzed. The study involved seven samples of microwave-dried macadamia nuts and one sample of conventionally dried nuts. Post-processing tests indicated that the conventionally dried nuts tast (more) ed more rancid. As for the other characteristics of the nuts, no significant differences were found between the microwave and conventional drying processes. The microwave-dried samples showed no statistically significant difference from one another except in their aroma. The results after the six-month storage period were similar to those found immediately after processing. As for modifications in the samples? sensory profile, there was a loss of intensity of the sensory attributes of texture and an increase in the sensory attributes of rancidity. From the sensory standpoint, it was concluded that the use of microwave-drying is viable, since the resulting product is similar to the conventionally dried one. The use of this type of energy reduced the drying time and therefore the impact on the product, particularly in terms of rancidity, when compared to the conventionally dried product.

233

Global grape aroma potential and its individual analysis by SBSE-GC-MS  

Among the aroma compounds present within grapes, a significant part is assumed to come from specific odourless precursors found mainly as glycosidic compounds which are known as bound fraction. In this paper, the individual composition of non-aromatic red grape bound fraction has been assayed for first time by SBSE-GC-MS and compared with the global total aroma potential measured spectrophotometrically at the wineries, in which the anthocyanins interferences have been removed. Glycosidic aroma compounds have been extracted by macerating grapes with different extractants (EtOHaq or SO2) at different times and subjected to acidic hydrolysis at 70degreeC for 2h. The best extraction condition, expressed as the higher aroma compounds concentration (terpenes+C13 norisoprenoids+2-phenylethanol+C6...

234

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portion of the Department of La Paz, which includes the provinces of Ingavi, Aroma ... tinental sediments dating back to the Tertiary Period, including sandstone .... mental zones in the fol .... Boreholes were drilled on the basis of the experience ...

235

Characterization of aroma volatiles in tomatoes by sensory analyses.  

Using gas chromatography-olfactometry and aroma extract dilution analysis 34 aroma compounds were found with flavour dilution factors > or = 4. (Z)-3-hexenal, hexanal, 1-octen-3-one, methional, 1-penten-3-one and 3-methylbutanal belonged to the most odour-active aroma volatiles in fresh tomatoes. Smell, taste and aftertaste of different tomato cultivars were evaluated by quantitative descriptive analysis. By applying principal component analysis to both sensory attributes and chemical compounds (odour-active aroma volatiles, titratable acid and reducing sugars) the first three components explained 70% of the total variance. The data set was reduced to the sensory attributes intensive, tomato, sour, fruity, sweet and bitter as well as to important chemical compounds. Relations between chemical compounds and sensory attributes were found. PMID:9881368

236

Enhancing Safety and Aroma Appealing of Fresh-Cut Fruits and Vegetables Using the Antimicrobial and Aromatic Power of Essential Oils  

ABSTRACT: Microbial and aroma attributes are within the most decisive factors limiting safety and sensory appealing of fresh-cut fruits and vegetables. Alternatively, several plant essential oils (EOs) are constituted of several volatile active compounds and most of them present antimicrobial potential and had different aroma profile. Considering these premises, this hypothesis article states that safety and aroma appealing of fresh-cut produce could be improved with EO treatment. EOs could prevent fresh-cut fruit decay; however, their volatile constituents could be sorbed by the produce, and according to the aroma notes of the antimicrobial oil, sensorial appealing of odor, and flavor of the treated produce might be affected positively or negatively. Specifically, garlic oil is a natural ...

237

Carbonyl odorants contributing to the in-oven roast beef top note.  

Among the few papers related to the gas chromatography (GC)-olfactometric determination of important odorants in cooked beef aroma, only one uses roasting conditions, but none of them investigates the appealing aroma during the cooking of the piece of meat. The present paper investigates this top note as perceived from the oven, by analyzing the oven headspace using GC-"SNIF", a GC-olfactometric technique. From the different functional classes of odorants participating in overall in-oven aroma, this first paper focuses only on the role of aldehydes and ketones, as they represent the majority of aroma compounds formed during cooking. To ascertain the identification of these odorants, a microderivatization technique was used, based on (2,3,4,5,6-pentafluorophenyl)hydrazine. The resulting hydrazones exhibit very specific mass spectrometric fragments, leading to a sensitive and specific detection. A total of 23 carbonyl compounds were shown to contribute to the roast beef top note. PMID:16302780

238

Sensory Properties and Color Measurements of Dietary Chocolates with Different Compositions During Storage for Up to 360 Days  

In this work sensory characteristics (appearance – color, brilliance, shape and surface; texture – structure, break, firmness and chewiness; aroma – odor and taste) of dietary chocolates of different compositions were evaluated, in parallel with color parameter measurements. Color was determined ins...

239

Evaluation of Japanese Green Tea Extract Using GC/O with Original Aroma Simultaneously Input to the Sniffing Port Method (OASIS)  

Recent studies of natural aromas have focused on only the lowest odor threshold compounds. In this study, we evaluated the volatile compounds of Japanese green tea, comparing the original aroma simultaneously input to the sniffing port method (OASIS) with the aroma extract dilution analysis method (AEDA). Geraniol, indole and linalool were classified in the low odor threshold by AEDA. Using OASIS, geraniol showed enhancement of the green character and indole showed strengthening the overall green tea odor, but linalool gave the same result as AEDA. On the other hand cis-3-hexenol, decanal and ?-ionone were classified in the high odor threshold by AEDA, OASIS showed enhancement of the green, tea-leafy, and sweet characters respectively. We added these compounds to a Japanese green tea infusion and evaluated it. The results showed great similarity to the OASIS results. In conclusion, OASIS is an effective technique by which to evaluate mixtures of volatile compounds with original aromas.   

240

Dedication and Perspiration Builds The Next Generation Life - Nasa  

Oct 29, 2007 ... The Clean Water Diary ... of the water processor to remove different types of contaminants from the waste water. ... Participants even microwave meals inside the module to generate water vapor and the aroma from the food.

 
 
 
 
241

Print - Nasa  

Oct 29, 2007 ... The Clean Water Diary ... of the water processor to remove different types of contaminants from the waste water. ... Participants even microwave meals inside the module to generate water vapor and the aroma from the food.

242

Volatile constituents of wild citrus Mangshanyegan (Citrus nobilis Lauriro) peel oil.  

Volatiles of a wild mandarin, Mangshanyegan (Citrus nobilis Lauriro), were characterized by GC-MS, and their aroma active compounds were identified by aroma extract dilution analysis (AEDA) and gas chromatography-olfactometry (GC-O). The volatile profile of Mangshanyegan was compared with those of other four citrus species, Kaopan pummelo (Citrus grandis), Eureka lemon (Citrus limon), Huangyanbendizao tangerine (Citrus reticulata), and Seike navel orange (Citrus sinensis). Monoterpene hydrocarbons predominated in Mangshanyegan, in particular d-limonene and ?-myrcene, which accounted for 85.75 and 10.89% of total volatiles, respectively. Among the 12 compounds with flavor dilution factors (FD) = 27, 8 oxygenated compounds, including (Z)- and (E)-linalool oxides, were present only in Mangshanyegan. The combined results of GC-O, quantitative analysis, odor activity values (OAVs), and omission tests revealed that ?-myrcene and (Z)- and (E)-linalool oxides were the characteristic aroma compounds of Mangshanyegan, contributing to the balsamic and floral notes of its aroma. PMID:22352344

243

Development of Conductive Polymer Analysis for the Rapid ...  

Oct 4, 2012 ... Description: Conductive polymer analysis, a type of electronic aroma ... methods, new instrument architecture for sampling, sample preparation, ... The collective output from a 32-sensor array produced unique electronic ...

244

Efeito da castração sobre parâmetros químicos, físico-químicos e sensoriais da carne caprina de animais mestiços/ Effect of castration on chemical, phisico-chemical and sensorial parameters of the "mestiço" goat meat  

Abstract in portuguese Foi estudado o efeito da castração sobre a umidade, cinzas, gordura, proteína, cálcio, ferro, fósforo, valores de pH, atividade de água, aparência, aroma caprino, aroma de carne assada, sabor, suculência, maciez, textura e qualidade total da carne caprina de animais mestiços. Dentre os parâmetros analisados, rigorosamente a castração dos animais teve efeito significativo apenas em relação ao cálcio, cujo teor aumentou em 33%. Abstract in english The effect of castration on moisture, ashes, fat, protein, calcium, iron, phosphorus, pH value, water activity, appearance, "goaty" aroma, roasted meat aroma, flavour, juiciness, tenderness, texture and overall palatability of goat meat from "mestiços" animals were studied. Among the parameters analysed, the castration of animals had a significant effect only on calcium content, whose content increased in 33%.

245

Structural and physical effects of aroma compound binding to native starch granules  

Abstract The interaction and physical/structural effects of aroma compounds, at high concentrations on dry native starch granules were studied using eight selected model compounds: acetaldehyde, dimethyl sulphide, diacetyl, allyl isothiocyanate, ethyl butyrate, citral, octanol and butyric acid. The maize, potato and pea starches used represent different typical structural and chemical starch characteristics. Retention of the different aroma compounds varied from a few to one hundred percent and starch was found to induce as well as reduce aroma evaporation depending on the aroma compound and the starch type. As deduced from DSC, powder XRD and SEM analyses, citral, butyric acid and octanol exerted specific effects on the starch granules manifested in local melting of crystalline layers and...

246

Evolution of yeasts and lactic acid bacteria during fermentation and storage of Bordeaux wines  

It is now well established that wine-related lactic acid bacteria (LAB), especially Oenococcus oeni, possess glycosidase activities that positively contribute to wine aroma through the hydrolysis of grape-derived aroma precursors. In our recent studies, we have identified and characterised several LAB glycosidases with potential in these terms. Here, we report that both a glucosidase and an arabinosidase from O. oeni can release high amounts of monoterpenes from natural substrates under optimal conditions, indicating that these intracellular enzymes might play a significant role in the hydrolysis of aroma precursors during malolactic fermentation. The enzymes from O. oeni exhibited broad substrate specificities (release of both primary/tertiary terpene alcohols) and were even active in grape juice. Further, a sensory panel clearly preferred enzyme-treated Riesling wines over the controls and affirmed that the glycosidases from O. oeni could improve the typical Riesling aroma. PMID:16346661

247

Identification of volatile aroma compounds in processed cheese analogues based on different types of fat  

The simple and rapid solid-phase micro-extraction method using gas chromatography was used for the identification and quantification of volatile aroma compounds in various types of processed cheese analogues produced from different types of fat (butter, butter oil, coconut oil, palm oil, and sunflower oil). In total, 31 organic compounds belonging to five chemical groups were identified, with the alcohols and fatty acids quantitatively predominant. The contents of the aroma compounds (the so-called aroma profiles) of the analogues and corresponding fats used as raw materials were compared. Significant differences (p < 0.05) were found between samples. The highest total content of aroma compounds was found in coconut oil analogue ((547.30 ? 9.82) mg kg?1), the lowest in palm oil analogue ((...

248

Aroma impact components of Brazilian Cabernet Sauvignon wines using detection frequency analysis (GC-olfactometry)  

The aroma profiles of Cabernet Sauvignon wines from a new grape growing region, Santa Catarina State, Brazil, were established for the first time using a Gas-chromatography-olfactometry (GC-O). Two wines were submmited to detection frequency analysis (DFA) (n=8), one having vegetative characteristics (SJA wine) and one with red fruits and jam aromas (BR wine) in a prior sensory analysis. Fourteen impact aroma descriptors were selected for judging by DFA analysis. Among these, nine compounds were identified using GC-MS, chromatographic retention times and characteristic odours: acetic acid, butyric acid, isovalerianic acid, 2-phenylethanol, methional, 2-methoxy-3-isobutylpyrazine (MIBP), b-damascenone, b-ionone and furaneol. In most, furaneol was associated with jam or caramel aroma by GC-O...

249

Contribution of non-volatile and aroma fractions to in-mouth sensory properties of red wines: Wine reconstitution strategies and sensory sorting task  

This work explores to what extent the aroma or the non-volatile fractions of red wines are responsible for the overall flavor differences perceived in-mouth. For this purpose, 14 samples (4 commercial and 10 reconstituted wines), were sorted by a panel of 30 trained assessors according to their sensory in-mouth similarities. Reconstituted wines were prepared by adding the same volatile fraction (coming from a red wine) to the non-volatile fraction of 10 different red wines showing large differences in perceived astringency. Sorting was performed under three different conditions: (a) no aroma perception: nose-close condition (NA), (b) retronasal aroma perception only (RA), and (c) allowing retro- and involuntary orthonasal aroma perception (ROA). Similarity estimates were derived from the s...

250

Taste and aroma of fresh and stored mandarins  

Abstract During the last decade there has been a continuous rise in consumption of fresh easy to peel mandarins. However, mandarins are much more perishable than other citrus fruit, mainly due to rapid deterioration in sensory acceptability after harvest. In the current review we discuss the biochemical components involved in forming the unique flavor of mandarins, and how postharvest storage operations influence taste and aroma and consequently consumer sensory acceptability. What we perceive as mandarin flavor is actually the combination of basic taste, aroma and mouth feel. The taste of mandarins is principally governed by the levels of sugars and acids in the juice sacs and the relative ratios among them, whereas the aroma of mandarins is derived from a mixture of different aroma volat...

251

INDIVIDUAZIONE DI INDICATORI DI QUALITÀ E MIGLIORAMENTO DEL PROCESSO PRODUTTIVO IN DRUPACEE (PESCO) MEDIANTE METODOLOGIE PROTEOMICHE INNOVATIVE  

Fruit ripening is a complex process genetically determined and environmentally regulated that involves drastic changes in various physiological and biochemical aspects. These events include chlorophyll breakdown, increased starch degradation and simple sugar biosynthesis, development of aroma compon...

252

Volatile composition of partially fermented wines elaborated from sun dried Pedro Ximenez grapes  

In this work, we used a cell immobilisation system consisting of Penicillium chrysogenum fungi (GRAS) bound to the osmotolerant yeast strains Saccharomyces cerevisiae X4 and X5 for the partial fermentation of raisin musts. The resulting wines were compared with others obtained by partial fermentation of musts with free yeasts and with a traditionally produced sweet wine (i.e. without fermentation of the must). The analysis of volatile compounds grouped by aroma series showed the partially fermented musts had a more complex aroma than the traditional wine. Specially prominent among aroma series was that of ripe fruit, followed by the milky and chemical series. The volatiles with the greatest impact on wine aroma as assessed in terms of odour activity were ethyl hexanoate, ethyl octanoate, b...

253

Process Optimization for Solid Extraction, Flavor Improvement and Fat Removal in the Production of Soymilk From Full Fat Soy Flakes  

Traditionally soymilk has been made with whole soybeans; however, there are other alternative raw ingredients for making soymilk, such as soy flour or full-fat soy flakes. US markets prefer soymilk with little or no beany flavor. modifying the process or using lipoxygenase-free soybeans can be used to achieve this. Unlike the dairy industry, fat reduction in soymilk has been done through formula modification instead of by conventional fat removal (skimming). This project reports the process optimization for solids and protein extraction, flavor improvement and fat removal in the production of 5, 8 and 12 {sup o}Brix soymilk from full fat soy flakes and whole soybeans using the Takai soymilk machine. Proximate analyses, and color measurement were conducted in 5, 8 and 12 {sup o}Brix soymilk. Descriptive analyses with trained panelists (n = 9) were conducted using 8 and 12 {sup o}Brix lipoxygenase-free and high protein blend soy flake soymilks. Rehydration of soy flakes is necessary to prevent agglomeration during processing and increase extractability. As the rehydration temperature increases from 15 to 50 to 85 C, the hexanal concentration was reduced. Enzyme inactivation in soy flakes milk production (measured by hexanal levels) is similar to previous reports with whole soybeans milk production; however, shorter rehydration times can be achieved with soy flakes (5 to 10 minutes) compared to whole beans (8 to 12 hours). Optimum rehydration conditions for a 5, 8 and 12 {sup o}Brix soymilk are 50 C for 5 minutes, 85 C for 5 minutes and 85 C for 10 minutes, respectively. In the flavor improvement study of soymilk, the hexanal date showed differences between undeodorized HPSF in contrast to triple null soymilk and no differences between deodorized HPSF in contrast to deodorized triple null. The panelists could not differentiate between the beany, cereal, and painty flavors. However, the panelists responded that the overall aroma of deodorized 8 {sup o}Brix triple null and HPSF soymilk are lower than the undeodorized triple null and HPSF soymilk. The triple null soymilk was perceived to be more bitter than the HPSF soymilk by the sensory panel due to oxidation on the triple null soy flakes. This oxidation may produce other aroma that was not analyzed using the GC but noticed by the panelists. The sensory evaluation results did show that the deodorizer was able to reduce the soymilk aroma in HPSF soymilk so it would be similar to triple null soymilk at 8 {sup o}Brix level. Regardless of skimming method and solids levels, the fat from the whole soybean milk was removed less efficiently than soy flake milk (7 to 30% fat extraction in contrast to 50 to 80% fat extraction respectively). In soy flake milk, less fat was removed as the % solid increases regardless of the processing method. In whole soybean milk, the fat was removed less efficiently at lower solids level milk using the commercial dairy skimmer and more efficient at lower solids level using the centrifuge-decant method. Based on the Hunter L, a, b measurement, the color of the reduced fat soy flake milk yielded a darker, greener and less yellow colored milk than whole soymilk ({alpha} < 0.05), whereas no differences were noticed in reduced fat soybean milk ({alpha} < 0.05). Color comparison of whole and skim cow's milk showed the same the same trend as in the soymilk.

254

Componentes voláteis do café torrado. Parte II. Compostos alifáticos, alicíclicos e aromáticos/ Volatile components in roasted coffee. Part II. Aliphatic, alicyclic and aromatic compounds  

Abstract in english This review is about the aliphatic, alicyclic and aromatic compounds (non-heterocyclic compounds) that are present in the volatile fractions of roasted coffees. Herein, the contents, aroma precursors and the sensorial properties of volatile phenols, aldehydes, ketones, alcohols, ethers, hydrocarbons, carboxylic acids, anhydrides, esters, lactones, amines and sulphur compounds are discussed. Special attention is given to the compounds of these groups that are actually important to the final aroma of roasted coffees.

255

Recovery of volatile aroma compounds from black currant juice by vacuum membrane distillation  

This study evaluated the recovery of seven characteristic black currant aroma compounds by vacuum membrane distillation (VMD) carried out at low temperatures (10-45 degreesC) and at varying feed flow rates (100-500 l/h) in a lab scale membrane distillation set tip. VMD at feed flow from 100 to 500 l/h at 30 degreesC gave concentration factors, calculated for each aroma compound as C-permeate/C-feed: from similar to4 to 15. The concentration factors increased with decreased juice temperature during VMD; at 10 degreesC concentration factors of 21-31 were obtained for the highly volatile aroma esters. The recovered levels of the highly volatile aroma compounds ranged from 68 to 83 vol.% with a feed volume reduction of 5 vol.% (10 degreesC, 400 l/h). The theoretically predicted aroma recovery as a function of the feed volume reduction was in accordance with the experimentally obtained values. VMD thus turned out to be a promising technique for gentle stripping of black currant juice aroma compounds.

256

Volatile composition and sensory properties of Vitis vinifera red cultivars from north west Spain: correlation between sensory and instrumental analysis.  

The aroma and volatile composition of wines from five red cultivars from NW Spain (Brancellao, Mencía, Merenzao, Mouratón and Sousón) have been studied by gas chromatography-mass spectrometry (GC-MS) and sensory descriptive analysis (SDA) during three consecutive vintages (2007-2009) in order to characterize these wines. In addition, relationships between the instrumental (volatile) and sensory variables were analyzed through the application of partial least squares regression (PLSR). Results revealed that the effect of "cultivar" was very important as a third of compounds (16 in total) varied significantly (P?0.05) among varieties. Mencía wines presented the highest concentrations of ?-nonalactone, whereas Sousón wines were the richest in monoterpene compounds. On the contrary, no significant difference was observed with respect to the esters content, probably as a consequence of using the same yeast for all vinifications. Twenty out of 51 quantified volatile compounds were present in some samples at concentrations higher than their corresponding odor thresholds (OAV>1), thus contributing to the final wine aroma. Partial least square (PLS) regression was applied to volatile compounds with OAV>0.2 and aroma descriptors with %GM>10. PLSR yielded a satisfactory model for the prediction of four important aroma descriptors in this set of wines--aroma quality, aroma intensity, herbaceous and red fruit--from instrumental analysis data. This work contributes to gaining knowledge about the sensory profiles and its relation to the volatile composition of minority Galician red grape cultivars. PMID:22365127

257

Does olfactory specific satiety take place in a natural setting?  

Olfactory-specific satiety (OSS) is characterized by a specific decrease in the odor pleasantness of a food eaten to satiety or smelled without ingestion. The usual protocol for studying OSS takes place in laboratory, a setting rather removed from the real world. Here, we set out to examine OSS in a natural setting: during a meal in a restaurant. We hypothesized that an aroma contained in a food that is eaten at the beginning of a meal decreases the pleasantness of the flavor of a food with the same aroma eaten at the end of the meal. In the first experiment (Experiment 1), a test group received an appetizer flavored with a test aroma (anise) at the beginning of the meal. After the main dish, they received a dessert flavored with the same aroma. A control group received the same aromatized dessert, but after a non-aromatized appetizer. This experiment was replicated (Experiment 2) using verbena as the test aroma. For both experiments, results revealed that aroma pleasantness, but not intensity or familiarity, significantly decreased in the test groups vs. the control groups. These findings extend the concept of OSS to a realistic eating context. PMID:23079143

258

Comparison of two microalgal diets. 2. Influence on odorant composition and organoleptic qualities of raw oysters (Crassostrea gigas).  

Oyster farming is of real economic interest in France. Oyster farmers attach more and more importance to improving the growth and the quality of their oysters. Some fatty acids known to be aroma precursors originate from microalgae such as Skeletonema costatum and Tahitian isochrysis clone. These microalgae were used to fatten oysters in order to observe their role in the development of oysters' aroma. This study shows that the profile of fatty acids of oysters is influenced by the contribution of fatty acids from the two microalgae (as reported in the first paper in this series: Pennarun, A.-L.; Prost, C.; Haure, J.; Demaimay, M. Comparison of Two Microalgal Diets. 1. Influence on the Biochemical and Fatty Acid Compositions of Raw Oysters (Crassostrea gigas). J. Agric. Food Chem. 2003, 51, 2006-2010 (in this issue)]. As a consequence, a microalgal diet causes changes in oysters' aroma composition. Aroma concentration depends on the content of fatty acids that are aroma precursors in oysters. Some aromas are characteristic of the diet of S. costatum, such as 6-methyl-5-hepten-2-one (ether odor), and others are characteristic of T. isochrysis, such as 3-nonyne (cucumber, marine odor), 6-(E)-nonen-1-ol (green and fresh odor), and 4-ethylbenzaldehyde (aniseed odor). Moreover, the organoleptic qualities (odor, taste, and texture) of oysters are modified by the diet of microalgae. PMID:12643667

259

Caracterização e extração de compostos voláteis de resíduos do processamento de maracujá (Passiflora edulis Sims f. flavicarpa degener)/ Characterization and extraction of volatile compounds from passion fruit (Passiflora edulis Sims f. flavicarpa degener) processing waste  

Abstract in portuguese Este estudo objetivou extrair e identificar compostos voláteis presentes nos resíduos de processo de maracujá. Obtiveram-se destilados a partir de resíduos de maracujá através das técnicas de hidrodestilação simples e hidrodestilação com arraste de gás nitrogênio. Os compostos voláteis presentes nos destilados foram capturados por microextração em fase sólida, empregando-se fibra Carboxen/DVB/DMS, e identificados por cromatografia gasosa acoplada com espe (more) ctrômetro de massa, usando a coluna capilar de sílica fundida CP WAX 52. Foram identificados trinta e um compostos voláteis no extrato obtido pela técnica de hidrodestilação simples, sendo os principais compostos: neral (26,19%), cinamato de metila (18,52%), linalol (16,82%), 1-undecanol (5,60%), cis-óxido de linalol (4,41%), benzaldeído (3,92%) e 1-hexanol (3,48%). Para a hidrodestilação com arraste de gás nitrogênio, trinta compostos foram identificados, sendo que, em maior porcentagem de área, destacaram-se: cinamato de metila (30,41%), neral (24,46%), ?-ionona (13,81%), linalol (4,0%) e acido butanoico (2,19%). O presente estudo revelou que os resíduos de maracujá apresentam compostos voláteis que podem ser extraídos na forma de aromas, apresentando potencial para gerar essências naturais com valor agregado. Abstract in english The aim of this study was to extract and identify volatile compounds from passion fruit residues generated during processing. Distillates of passion fruit residues were obtained from the techniques of simple hydrodistillation and hydrodistillation by passing nitrogen gas. The volatile compounds present in the distillates were captured by solid phase microextraction with Carboxen/DVB/DMS fiber. The volatile compounds were indentified by gas chromatography with mass spectro (more) metry using a fused sillica capillary column with a CP WAX 52 stationary phase. Thirty one compounds were indentified by simple hydrodistillation technique. The main compounds were: neral (26.19%), methyl cinnamate (18.52%), linalool (16.82%), 1-undecanol (5.60%), cis-linalool oxide (4.41%), benzaldehyde (3.92%) and 1-hexanol (3.48%). For the hydrodistillation by passing nitrogen gas, thirty compounds were identified and the ones which presented higher area percentage were: methyl cinnamate (30.41%), neral (24.46%), ?-ionone (13.81%), linalool (4.0%) and butanoic acid (2.19%). The present study revealed that passion fruit waste contained volatile compounds that could be extracted as aromas products, presenting potential for the production of value-added natural essences.

260

Influence of Butter and/or Vegetable oil on Flavors of Roux Prepared from Wheat Flour and Fat/Oil  

To examine the influence of preparation method (white or brown roux prepared by heating to 130°C and 170°C, respectively) and fat/oil ingredients (butter fat, corn oil and salad oil), the flavors of roux prepared from wheat flour were studied by sensory analysis and chemical analyses of the aroma compounds with gas chromatography (GC) and GC-MS, followed by GC-Olfactometry.Sensory evaluation of roux flavors in butter roux, corn oil roux and salad oil roux showed that the butter roux had a strong sweet odor and both the butter roux and the corn oil roux had generally preferable flavor. Then, the various types of roux were subjected to chemical analyses.Through comparisons of each component for the butter roux and the corn oil roux, it was found that the difference in flavor was especially apparent in the amount of carbonyl compounds and Maillard reaction products. That is, the butter roux was composed of largely aliphatic methyl ketones (C7-C11) in both the white roux (heated to 130°C) and the brown roux (heated to 170°C), and mostly furans and somewhat cyclic ketoenols such as maltol in the brown roux, while the corn oil roux included more benzaldehyde in the white roux, and phenylacetaldehyde and (E, E)-2, 4-decadienal in the brown roux. Furthermore, GC-O analysis showed that butanoic acid, which confers a rancid odor, ?-decalactone, which confers a floral odor, and furfuryl alcohol and 2-nonanone with a floral odor, respectively might contribute to the flavor of the butter roux, while (E, E) 2, 4-decadienal with a pungent odor and benzaldehyde with an almond-like odor might affect the flavor of the corn oil roux. Therefore, the difference of flavor of the two roux may originate in the composition of the fatty acids of fat/oil.Mixing various fat/oil in the form of butter and corn oil showed the effect of using proportions of ingredients for aroma of the cooked product, especially in the white roux.   

 
 
 
 
261

REVIEW. BACTERIAS ACIDO LÁCTICAS: PAPEL FUNCIONAL EN LOS ALIMENTOS/ REVIEW LACTIC ACID BACTERIA: FUNCTIONAL ROLE IN THE FOODS/ BACTÉRIAS ÁCIDO LÁCTICAS: PAPEL FUNCIONAL NOS ALIMENTOS  

Abstract in portuguese As bacterias ácido lácticas têm sido importantes nos alimentos por séculos pela sua considerável contribuição ao valor dos produtos. Devido a varias das suas propriedades metabóllcas, as bacterias ácido lácticas desempenham um papel importante na industria alimentar, pela sua contribulção significante ao sabor, cheiro, textura, características sensoriais, propriedades terapêuticas e valor nutrlcional dos produtos alimentar. Este grupo está constituido de um (more) número de gêneros incluindo Lactococcus, Lactobaclllus, Enterococcus, Etreptococcus, Leuconostoc e Pediococcus. Alguns dos metabolltos produzidos por este tipo de bacterias são ácidos orgãnicos, sustãncias preservadoras, poli-sacáridos, vitaminas, adoçantes, cheiros e sabores entre outros. Esta revisão se enfoca em estudar a importãncia das bacterias ácido lácticas nos alimentos. Abstract in spanish Las bacterias ácido lácticas han sido importantes en los alimentos por siglos por su considerable contribución al valor de los productos. Debido a varias de sus propiedades metabólicas, las bacterias ácido lácticas desempeñan un papel importante en la industria alimentaria, por su contribución significante al sabor, olor, textura, características sensoriales, propiedades terapéuticas y valor nutricional de los productos alimentarios. Este grupo está compuesto d (more) e un número de géneros incluyendo Lactococcus, Lactobacillus, Enterococcus, Streptococcus, Leuconostoc y Pediococcus. Algunos de los metabolitos producidos por las este tipo de bacterias son ácidos orgánicos, sustancias preservantes, polisacáridos, vitaminas, endulzantes, olores y sabores entre otros. Esta revisión se enfoca en estudiar la importancia de las bacterias acido lácticas en los alimentos. Abstract in english Lactic acid bacteria have been important in food for centuries for their significant contribution to product value. Because several of its metabolic properties, lactic acid bacteria play an important role in the food industry for his significant contribution to the flavor, aroma, texture, sensory characteristics, therapeutic properties and nutritional value of food products. This group is composed of a number of genera, including Lactococcus, Lactobacillus, Enterococcus, (more) Streptococcus, Leuconostoc and Pediococcus, among others. Some of the metabolites produced by these bacteria are organic acids, preservares substances, polysaccharides, vitamins, sweeteners, aromas and flavors, among others. This review focuses on studying the importance of lactic acid bacteria in food

262

Propriedades físicas de substitutos do cacau/ Physical properties of cocoa substitutes  

Abstract in portuguese O cacau em pó é obtido a partir da pasta de cacau, preparada com sementes que passaram pelos processos de fermentação, secagem, torrefação, moagem e prensa (para separação da manteiga de cacau). Nos últimos anos, houve aumento na oferta de gorduras substitutas à manteiga de cacau, diminuindo a dependência da indústria alimentícia em relação a esta, mas aumentando a demanda por cacau em pó. Nos países líderes de produção, o preço do cacau é afetado pe (more) lo clima, pragas e fatores políticos. Substitutos de cacau são substâncias que podem entrar na formulação de produtos que utilizam cacau em pó para substituí-lo parcial ou totalmente, com a finalidade de reduzir o preço do produto final, garantir a qualidade dos produtos dependentes de cacau na entressafra ou mesmo na possível ausência do cacau em pó no mercado. Os substitutos avaliados foram: farinha tostada de alfarroba, cupuaçu em pó, composto da semente de cacau e aromas. O objetivo neste trabalho foi avaliar fisicamente o cacau e seus substitutos por meio das análises de compactação, densidade, ângulo de repouso, isoterma de adsorção de umidade, tamanho de partícula, molhabilidade e umidade crítica relativa. Concluiu-se que os produtos analisados apresentaram diferentes propriedades físicas daquelas do cacau, sendo estas refletidas nas formulações em que serão aplicados e no melhor tipo de embalagem a ser utilizada. Abstract in english Cocoa powder is obtained from the paste of cocoa prepared with fermented, dried, toasted, grinded, and pressed seeds (to separate cocoa butter). In the last years, there has been more offers of cocoa butter substitutes decreasing the food industry dependence but increasing the demand for cocoa powder. Moreover, in the producing leader countries, the price of cocoa sub-products is affected by the climate, pests, and political issues. Cocoa substitutes are substances that c (more) an substitute, total or partially, the cocoa powder in the formulation of different products with the purpose of reducing the final price, guaranteeing the quality in the off season, or even during a possible short availability of cocoa powder in the market. The chosen substitutes were: toasted carob powder, cupuassu powder, and cocoa seed and aroma compound. The objective of this study was to evaluate cocoa and its substitutes through the analysis of physical parameters such as compaction, density, angle of repose, sorption isotherm, particle size, wettability, and critical relative humidity). As result, the substitutes showed different physical properties from those of cocoa, which can affect the formulations in which they could be applied.

263

Sensory stability of ultra-high temperature milk in polyethylene bottle.  

The objective of this study was to evaluate the sensory stability of ultra-high temperature (UHT) milk subjected to different heat treatments and stored at room temperature in white high density polyethylene bottles (HDPE) pigmented with titanium dioxide. Two lots of 300 units each were processed, respectively, at 135 and 141 degrees C/10 s using indirect heating and subsequently aseptically filled in an ISO class 7 clean room. These experimental lots were evaluated for appearance, aroma, flavor, and overall appreciation and compared to samples of commercial UHT milk purchased from local commercial stores. The time-temperature combinations investigated did not affect either the acceptability or the shelf life of the milk. Despite the limited light barrier properties of HDPE bottles, the product contained in the package tested exhibited good stability, with a shelf life ranging from 4 to 11 wk. Within this time period, the acceptability of the experimental lots was similar to that of the commercial products. The results achieved in this study contribute to turn the low-cost UHT system investigated into a technically viable option for small-size dairy processing plants. PMID:19200121

264

Production of flavour-active methionol from methionine metabolism by yeasts in coconut cream.  

Yeasts Candida kefyr NCYC143, Candida utilis CUM, Kluyveromyces lactis KL71, Saccharomyces bayanus SB1, Saccharomyces cerevisiae EC1118, Saccharomyces chevalieri CCICC1028, Candida famata (previously Torulopsis candida) CCICC1041 and Williopsis saturnus var. saturnus CBS254 were screened for their ability to produce flavour-active methionol (3-methylthio-1-propanol) in coconut cream supplemented with l-methionine. The yeasts varied with their ability to produce methionol from methionine with Saccharomyces cerevisiae EC1118 producing the most, followed by Kluyveromyces lactis KL71. Little methionol was produced by the other yeasts. Methionol production by Kluyveromyces lactis KL71 was subjected to further studies under different conditions of initial pH (4.0-6.3), temperature (20-33 °C), l-methionine concentration (0.05-0.25%) and yeast extract concentration (0-0.50%); optimal conditions were established at pH 5.0, 33.0 °C, 0.15% l-methionine and 0.05% yeast extract. CharmAnalysis™ using SPME-GC-MS was conducted on the coconut cream ferment; methional (3-methylthio-1-propanal), methionol and 2-phenylethyl acetate were found to be the most potent aroma-active compounds. The product of coconut cream fermentation by Kluyveromyces lactis KL71 may be considered as a novel, plant-based, natural and complex flavoring bioingredient in food applications. PMID:20805008

265

Design and performance evaluation of a new hybrid solar dryer for banana  

A hybrid solar dryer was designed and constructed using direct solar energy and a heat exchanger. The dryer consists of solar collector, reflector, heat exchanger cum heat storage unit and drying chamber. The drying chamber was located under the collector. The dryer was operated during normal sunny days as a solar dryer, and during cloudy day as a hybrid solar dryer. Drying was also carried out at night with stored heat energy in water which was collected during the time of sun-shine and with electric heaters located at water tank. The efficiency of the solar dryer was raised by recycling about 65% of the drying air in the solar dryer and exhausting a small amount of it outside the dryer. Under Mid-European summer conditions it can raise up the air temperature from 30 to 40 C above the ambient temperature. The solar dryer was tested for drying of ripe banana slices. The capacity of the dryer was to dry about 30 kg of banana slices in 8 h in sunny day from an initial moisture content of 82% to the final moisture content of 18% (wb). In the same time it reduced to only 62% (wb) moisture content in open sun drying method. The colour, aroma and texture of the solar dried products were better than the sun drying products. (author)

266

Soil analysis reveals the presence of an extended mycelial network in a Tuber magnatum truffle-ground.  

Truffles are hypogeous ectomycorrhizal fungi. They belong to the genus Tuber and are currently considered a hot spot in fungal biology due to their ecological and economic relevance. Among all the species, Tuber magnatum is the most appreciated because of its special taste and aroma. The aim of this work was to set up a protocol to detect T. magnatum in soil and to assess its distribution in a natural truffle-ground. We used the beta-tubulin gene as a marker to identify T. magnatum in the soil. This gene allowed us to trace the distribution of the fungus over the entire truffle-ground. Tuber magnatum was found, in one case, 100 m from the productive host plant. This study highlights that T. magnatum mycelium is more widespread than can be inferred from the distribution of truffles and ectomycorrhizas. Interestingly, a new haplotype - never described from fruiting body material - was identified. The specific detection of T. magnatum in the soil will allow to unravel the ecology of this fungus, following its mycelial network. Moreover, this new tool may have practical importance in projects aimed to increase large-scale truffle production, checking for T. magnatum persistence in plantations. PMID:19780830

267

Quality Characteristics and Acceptability of Bread Produced with Supplementation of Dolichos lab lab Beans  

The viability of production of good quality and acceptable bread with substitution of wheat flour with Dolichos lab lab (Lab lab purpureus) was investigated. The bread was analyzed for protein, moisture, general bread quality and sensory properties. The protein content of bread was elevated by up to about 20% and the moisture content reduced by about 10% without significant changes in bread taste, odor, volume and general bread quality. Substitution levels of up to 10% produced bread with quality characteristics not significantly different from the control. Sensory evaluation showed no significant differences between the control bread and the Dolichos supplemented breads up to 15% in the sensory attributes of aroma, crumb appearance, texture, crust colour, loaf shape, taste and general acceptability (p < 0.05). The crumb colour changed from creamish white to dull brown and a gradual hardening of crumb texture was observed as the addition of Dolichos lab lab bean flour increased. Above 15% substitution levels, the acceptability declined because of the compact texture of the crumb and the strong beany flavor of the product. Results indicate that acceptable breads can be produced by substitution of up to 15% wheat flour with dolichos bean flour.   

268

Molecular interaction between COP1 and HY5 defines a regulatory switch for light control of Arabidopsisdevelopment  

p-Hydroxyphenylbutan-2-one, the characteristic aroma compound of raspberries (Rubus idaeus L.), is synthesized from p-coumaryl-coenzyme A and malonyl-coenzyme A in a two-step reaction sequence that is catalyzed by benzalacetone synthase and benzalacetone reductase (W. Borejsza-Wysocki and G. Hrazdina [1994] Phytochemistry 35: 623-628). Benzalacetone synthase condenses one malonate with p-coumarate to form the pathway intermediate p-hydroxyphenylbut-3-ene-2-one (p-hydroxybenzalacetone) in a reaction that is similar to those catalyzed by chalcone and stilbene synthases. We have obtained an enzyme preparation from ripe raspberries that was preferentially enriched in benzalacetone synthase (approximately 170-fold) over chalcone synthase (approximately 14-fold) activity. This preparation was used to characterize benzalacetone synthase and to develop polyclonal antibodies in rabbits. Benzalacetone synthase showed similarity in its molecular properties to chalcone synthase but differed distinctly in its substrate specificity, response to 2-mercaptoethanol and ethylene glycol, and induction in cell-suspension cultures. The product of the enzyme, p-hydroxybenzalacetone, inhibited mycelial growth of the raspberry pathogen Phytophthora fragariae var rubi at 250 [mu]M. We do not know whether the dual activity in the benzalacetone synthase preparation is the result of a bifunctional enzyme or is caused by contamination with chalcone synthase that was also present. The rapid induction of the enzyme in cell-suspension cultures upon addition of yeast extract and the toxicity of its product, p-hydroxybenzalacetone, to phytopathogenic fungi also suggest that the pathway may be part of a plant defense response. PMID:9659918

269

Use of a Fungal Lipase for Enhancement of Aroma in Black Tea  

Lipases produced extracellularly by bacteria and fungi are being widely used in the food industry for flavour development. During tea processing, the possibility of enhancing the flavour of tea by the exogenous addition of lipase has not been reported. It was therefore considered worthwhile to amend tea leaves with microbial lipases and observe the changes in the flavour profile of the finished product. Among a few fungal lipases screened, the enzyme secreted by Rhizomucor miehei increased the formation of desired flavour compounds. Hence, studies were initiated to achieve enhanced production of this industrially useful enzyme. Under solid-state fermentation R.M. miehei produces an extracellular lipase in copious amounts on a simple solid substrate within 96 h, which is active at lower temperatures and at near-neutral pH. These attributes make this enzyme suitable for use during the manufacturing of tea, where reactions are carried out at temperatures of 15 to 20°C and pH range of 5 to 7. In the present study, exogenous addition of lipase resulted in an increase in flavour volatiles, which contribute to the aroma of tea.   

270

Addition of alpha-ketoglutarate enhances formation of volatiles by Staphylococcus carnosus during sausage fermentation  

The effect of leucine and alpha-ketoglutarate addition on transamination of branched-chain amino acids was studied in model minces inoculated with Pediococcus pentosaceus and Staphylococcus carnosus. Leucine addition changed the ratio of volatile breakdown products of leucine, isoleucine and valine but not the total amount of the volatiles and it was concluded that the amount of free amino acids does not limit transamination of amino acids. The addition of alpha-ketoglutarate resulted in increased levels of methyl-branched aldehydes and insignificant positive changes in methyl-branched acid production. The results were verified in real fermented sausages with no, low (0.09% w/w) and high (0.36% w/w) addition of added alpha-ketoglutarate since the levels of the flavour intensive methyl-branched aldehydes and acids were drastically increased in sausages added a-ketoglutarate. The catabolism of phenylalanine was also induced by alpha-ketoglutarate and there were further indications of increased transamination ofaspartate. A triangular test showed that the flavour of sausages with no and low addition of alpha-ketoglutarate could be clearly distinguished from one another. Altogether the results presented in this paper point to glutamate dehydrogenase, the enzyme catalyzing regeneration of a-ketoglutarate, as a key enzyme in catabolism of amino acids and thereby also in aroma formation during sausage processing.

271

Uso de pulpa de tuna (opuntia boldinghii) en la elaboración de bebidas cítricas pigmentadas  

Abstract in portuguese Opuntia boldinghii Br et R. é uma espécie sem utilidade comercial. No entanto, investigações recentes têm demonstrado seu potencial pigmentario, pela presença de betalaínas. Neste estudo se formularam quatro bebidas cítricas (15% de suco de laranja + 15% de suco de toronja + 65% de água + 5% de polpa O. boldinghii) acondicionadas com 0; 0,5; 0,1% e 0,01% ácido ascórbico (formulações I, II, III e IV, respectivamente). Os sucos pasteurizados se conservaram sob (more) refrigeração a 7,0 ±1ºC em recipientes âmbar. Avaliaram-se semanalmente durante 21 dias bactérias mesófilas, mofos, fermento, NMP/ml de coliformes, pH, ºBrix, acidez tituláveis, betalaínas, carotenóides totais, vitamina C e parâmetros sensoriais (cor, aroma e sabor). A contagem de bactérias mesófilas para todas as formulações no primeiro dia avaliado foi 0,05) nos parâmetros: pH, ºBrix e acidez titulável; no entanto, se determinaram diferenças significativas no conteúdo de betalaínas, carotenóides totais e vitamina C (P Abstract in spanish Opuntia boldinghii Br et R. es una especie sin utilidad comercial. Sin embargo, investigaciones recientes han demostrado su potencial pigmentario por la presencia de betalaínas. En este estudio se formularon cuatro bebidas cítricas (15% de jugo de naranja + 15% de jugo de pomelo + 65% de agua + 5% de pulpa O. boldinghii) acondicionadas con 0; 0,5; 0,1% y 0,01% ácido ascórbico (formulaciones I, II, III y IV, respectivamente). Los jugos pasteurizados se conservaron bajo (more) refrigeración a 7,0 ±1ºC en envases ámbar. Se evaluaron semanalmente durante 21 días bacterias mesófilas, mohos, levaduras, NMP/ml de coliformes, pH, ºBrix, acidez titulable, betalaínas, carotenoides totales, vitamina C y parámetros sensoriales (color, aroma y sabor). El recuento de bacterias mésofilas para todas las formulaciones en el primer día evaluado fue 0,05) en los parámetros: pH, ºBrix y acidez titulable; sin embargo, se determinaron diferencias significativas en el contenido de betalaínas, carotenoides totales y vitamina C (P Abstract in english Opuntia boldinghii Br et R. is a species without commercial use. However, recent research has shown its potential as a colorant, due to the presence of betalains. In this study, four citric beverages (15% orange juice + 15% grape-fruit juice + 65% water + 5% O. boldinghii pulp) formulated with 0, 0.5%, 0.1% 0.01% ascorbic acid (formulations I, II, III and IV, respectively). The products were pasteurized and stored at 7.0 ±1ºC using amber bottles. Mesophilic bacteria, mo (more) lds, yeast, MPN/ml of coliforms, pH, ºBrix, titrable acidity, betalains, total carotenoids, vitamin C and sensorial parameters (color, aroma and flavor) were evaluated weekly during 21 days. The first day, mesophilic bacteria counts were 0.05) in pH, ºBrix and titrable acidity. Significant differences were found (P

272

Electronic nose and SPME-GAS cromatography for the study of the odor profile of whole milk power  

Abstract in spanish El presente estudio combina una nariz electrónica y microextracción en fase sólida por espacio de cabeza-cromatografía gaseosa para el análisis del aroma de leche entera en polvo elaborada en la región central de la Cuenca Lechera Argentina. Diferentes ensayos fueron realizados para definir el protocolo de análisis y la capacidad de discriminación de la nariz electrónica, la cual posee 28 sensores polímeros conductores. Con este fin, distintas muestras fueron an (more) alizadas mientras se producían cambios incrementales en parámetros operacionales de la nariz electrónica. Estos parámetros incluyen tiempo de equilibrio de la muestra y tiempo de llenado, equilibrio e inyección del loop. Microextracción en fase sólida del espacio de cabeza se usó para aislar los compuestos volátiles dimetil sulfide, pentanal, hexanal y ácido butírico, los cuales contribuyen al aroma y el sabor de la leche en polvo. Estos compuestos se caracterizaron y cuantificaron por cromatografía gaseosa con detector de ionización de llama. Se determinaron curvas de extracción, repetitibilidad y linealidad. Los límites de detección se encontraron en el rango de 0.6-400µgKg-1. Aplicando el método de correlación de Spearman se observaron diferencias en la relación lineal entre sensores y compuestos volátiles de acuerdo a la estación climática de elaboración de la leche en polvo. Este estudio muestra que la nariz electrónica puede ser aplicada para caracterizar el aroma de leche en polvo, en combinación con técnicas analíticas tales como microextracción en fase sólida por espacio de cabeza-cromatografía gaseosa. Abstract in english The present study describes the strength of the electronic nose and headspace solid-phase microextraction-gas chromatography (HS-SPME-GC) in food odor analysis. These methodologies were successfully applied to odor characterization of whole milk powder manufactured in a factory of the Central Dairy Area of Argentina. An electronic nose comprised of a set of 28 conducting polymeric sensors was used. Different assays were conducted in order to define the protocol of analysi (more) s and examine the discriminative capability of the E-nose. For that purpose, a series of samples were evaluated while selected E-nose parameters undergone incremental changes in a pre-assigned routine, including sample equilibrium time, loop fill time, loop equilibrium time and inject time. HS-SPME was used to isolate volatiles compounds such as dimethyl sulfide, pentanal, hexanal, and butyric acid, compounds that contribute significantly to describe the odor and flavor acceptance of whole milk powder. Isolated compounds were characterized and quantified by GC with FID detection. Extraction curves, limits of detection, repeatability, and linearity were investigated. Limits of detection ranged between 0.6-400µgKg-1. Applying the Spearman correlation method, differences in the lineal relation between sensors and volatile compounds were observed according to the season of powder production. This study shows that the electronic nose technology can be applied to milk powder odor characterization, complementing analytical techniques like HS-SPME-GC used in food odor research.

273

Caracterização e diversidade genética de cultivares de morangueiro/ Characterization and genetic diversity of strawberry cultivars  

Abstract in portuguese O objetivo deste trabalho foi caracterizar a diversidade genético-molecular, por marcadores RAPD, das dez principais cultivares de morangueiro utilizadas no País: Aromas, Bürkley, Camarosa, Campinas, Dover, Milsei-Tudla, Oso Grande, Santa Clara, Sweet Charlie e Vila Nova. O DNA foi extraído de folhas maduras, as análises RAPD foram realizadas com 26 primers e os produtos de amplificação separados por eletroforese. O coeficiente de Dice foi utilizado para estimar a (more) similaridade genética entre as cultivares e o método UPGMA para gerar o fenograma por meio do NTSYS. Houve amplificação de fragmentos consistentes com 19 primers, tendo sido encontrado polimorfismo em 14. Dos 116 fragmentos gerados, 84 foram polimórficos. As cultivares foram classificadas em dois grupos principais quanto à similaridade genética: cultivares destinadas à industrialização (Bürkley, Santa Clara e Vila Nova) e cultivares destinadas ao mercado in natura (demais cultivares). A similaridade foi menor no grupo das cultivares para consumo in natura (44-74%), o que ocorreu em função dos parentais serem diferentes. A maior similaridade genética ocorreu entre as cultivares de indústria Santa Clara e Vila Nova (98%), ambas obtidas pelo programa de melhoramento da Embrapa Clima Temperado, e provenientes dos mesmos parentais ('Konvoy-Cascata' e 'Lassen'). Padrões RAPD foram estabelecidos para a caracterização genética das dez cultivares de morangueiro estudadas. Abstract in english In this work we characterized the genetic-molecular diversity by RAPD markers of the main ten strawberry cultivars cultivated in Brazil: Aromas, Bürkley, Camarosa, Campinas, Dover, Milsei-Tudla, Oso Grande, Santa Clara, Sweet Charlie and Vila Nova. The DNA was extracted from mature leaves, the RAPD analysis were carried out with 26 primers and the amplification products were separated by electrophoreses. The coefficient of Dice was used to estimate the genetic similarity (more) among the cultivars and the UPGMA method to obtain the phenogram using NTSYS software. Bands were amplified with 19 primers, and showed polymorphism with 14. Out of 116 bands, 84 were polymorphic. The cultivars were classified in two main groups: industry cultivars (Bürkley, Santa Clara and Vila Nova) and fresh fruit market cultivars (other cultivars). The genetic similarity was lesser in the group of cultivars for fresh market (44-74%), in which the different clones were used as parents. The cultivars Santa Clara and Vila Nova, used for processing, showed the higher genetic similarity (98%), both cultivars were obtained at breeding program of Embrapa Clima Temperado, and are originated from the same parental clones ('Konvoy-Cascata' and 'Lassen'). Standard RAPD markers were established to genetic characterization of ten strawberry cultivars.

274

Microextração em fase sólida de 6-pentil-?-pirona produzida por fermentação em estado sólido/ Solid-phase microextraction of 6-pentyl-?-pyrone produced by solid-state fermentation  

Abstract in portuguese A substância 6-pentil-?-pirona (6-PP) é uma lactona com aroma característico de coco e uso aprovado pela agência americana Food and Drug Administration (FDA). O presente trabalho teve como objetivo ajustar as condições de microextração em fase sólida em headspace para a quantificação por cromatografia gasosa de 6-PP produzida pelo fungo Trichoderma harzianum a partir do pó da casca de coco verde. Para isto, foi realizado um estudo em que soluções padron (more) izadas de 6-PP foram adicionadas ao pó da casca de coco verde. A substância foi extraída por uma fibra de polidimetilsiloxano. Agitação e adição de solução de NaCl a 25% (p/v) resultaram em melhor reprodutibilidade nas análises. Um planejamento composto central foi empregado para estudar três fatores: temperatura de extração, tempo de condicionamento e tempo de extração. Boas respostas foram obtidas com a temperatura de 79 °C e tempo de extração de 29 minutos. O efeito da variável tempo de condicionamento não foi significativo e foi fixado em 2 minutos. Após o desenvolvimento do método analítico, este foi empregado para determinar a produção de 6-PP por fermentação em estado sólido realizada por Trichoderma harzianum e com o uso de pó da casca de coco verde como suporte para o processo. Abstract in english The lactone 6-pentyl-a-pyrone (6-PP) is a coconut-like aroma compound approved by the American agency Food and Drug Administration (FDA) for food use. The aim of the present study was to improve the extraction conditions of headspace solid-phase microextraction coupled with gas chromatography to quantify the 6-PP produced by Trichoderma harzianum using green coir dust. To achieve this purpose, standard solutions of 6-PP were added to green coir dust. The compound was extr (more) acted by a polydimethylsiloxane fiber. Agitation and addition of a 25% NaCl solution (w/v) resulted in better reproducibility. A central composite design was applied to study three factors: extraction temperature, conditioning time, and extraction time. Good responses were obtained when the extraction temperature was 79 °C, and the extraction time was 29 minutes. The conditioning time effect was not significant and was established at 2 minutes. After the development of the analytical method, it was employed to determine the 6-PP production by Trichoderma harzianum in solid-state fermentation using green coir dust as the support material for the process.

275

Determination of 2H/1H and 13C/12C isotope ratios of (E)-methyl cinnamate from different sources using isotope ratio mass spectrometry.  

For the authenticity assessment of (E)-methyl cinnamate from different origins, combustion/pyrolysis-isotope ratio mass spectrometry (C/P-IRMS) was used by an elemental analyzer (EA) and on-line capillary gas chromatography coupling (HRGC-C/P-IRMS). For that reason, (E)-methyl cinnamate self-prepared from synthetic, natural, and semisynthetic educts was analyzed in comparison to the commercial synthetic and natural ester. In addition, (E)-methyl cinnamate from basil extract and a number of commercial natural aromas was investigated. The data of self-synthesized synthetic (E)-methyl cinnamate, i.e., delta(13)C(V)(-)(PDB) = -33.8 per thousand and delta(2)H(V)(-)(SMOW) = +349 per thousand, corresponded with that found for the commercial synthetic samples (-29.5 to -31.4 per thousand and +328 to +360 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively). The ester produced from natural educts by acid as well as Candida antarctica catalysis revealed delta(13)C(V)(-)(PDB) = -25.6 and -30.1 per thousand as well as delta(2)H(V)(-)(SMOW) = -162 and -169 per thousand, respectively. Acid-catalyzed semisynthetic products differed in their delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) values depending on the origin of their educts. For the ester from synthetic methanol and natural cinnamic acid, -27.3 and -126 per thousand were determined for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively, whereas for the ester produced from natural methanol and synthetic acid delta(13)C(V)(-)(PDB) = -30.6 per thousand and delta(2)H(V)(-)(SMOW) = +287 per thousand were found. Basil extract showed -28.9 and -133 per thousand for delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW), respectively. Commercial aromas declared to be natural revealed delta(13)C(V)(-)(PDB) and delta(2)H(V)(-)(SMOW) data ranging from -25.7 to -28.5 per thousand as well as -85 to -191 per thousand, respectively, indicating, in part, incorrect declaration. PMID:15137854

276

Avaliação de cultivares de arroz de terras altas sob condições de sequeiro em Cassilândia, MS/ Upland field rice cultivars evaluation under rainfed condition in Cassilândia, MS  

Abstract in portuguese O uso de cultivares selecionadas é uma das tecnologias de mais fácil adoção pelo agricultor, pois além de incrementar a produtividade, é um dos insumos de menor custo na produção agrícola. Assim, é fundamental obter informações sobre o desempenho de novas cultivares, nas mais diversas regiões de cultivo. Objetivou-se, neste trabalho avaliar o comportamento de cultivares de arroz de terras altas (Oryza sativa L.) (BRS Aroma, BRS Bonança, BRS Colosso, BRSMG Co (more) nai, BRSMG Curinga, BRS Soberana, BRS Talento e IAC 202), sob condições de sequeiro, na região de Cassilândia, MS. O delineamento experimental foi o de blocos ao acaso, com quatro repetições. A semeadura foi realizada em 30 de novembro de 2005, no espaçamento de 0,40 m entre linhas e 70 sementes viáveis por metro. As cultivares BRS Talento, IAC 202 e BRS Soberana apresentaram comportamento superior. As cultivares BRS Soberana, BRS Bonança, BRS Colosso, IAC 202 e BRS Talento apresentaram maior rendimento de grãos inteiros. É possível obterse boa produtividade (acima de 3.000 kg ha-1), na cultura do arroz de terras altas sob condições de sequeiro no município de Cassilândia, MS, desde que sejam utilizadas cultivares adequadas. Abstract in english The use of selected cultivars is one of the easiest technologies for adoption by the farmer; besides yield increase, it offers lower cost in the agricultural production. Thus, it is fundamental to obtain information about the performance of new cultivars, from the most diverse cropping regions. The purpose of this study was to evaluate the performance of the upland rice (Oryza sativa L.) (BRS Aroma, BRS Bonança, BRS Colosso, BRSMG Conai, BRSMG Curinga, BRS Soberana, BRS (more) Talento and IAC 202) under rainfed condition in Cassilândia, MS, Brazil. A randomized complete block design, with four replications was used. The seeds were sowed on November 30 2006, with 0.40 m between rows and a density of 70 viable seeds per meter. The results showed that BRS Talento, IAC 202, and BRS Soberana presented better performance. BRS Soberana, BRS Bonança, BRS Colosso, IAC 202, and BRS Talento presented larger whole grain yield. It is possible to obtain good rice grain yield higher than 3,000 kg ha-1, under rainfed condition in Cassilândia, MS, since appropriate cultivars are used.

277

Addition of pasture plant essential oil in milk: influence on chemical and sensory properties of milk and cheese.  

The aim of this experiment was to study the effect of the addition, to milk, of an essential oil (EO) obtained from the hydrodistillation of plants collected from a mountain natural pasture on the milk and cheese sensory properties. The EO was mainly composed of terpenoid compounds (67 of the 95 compounds identified) as well as ketones, aldehydes, alcohols, esters, alkanes, and benzenic compounds. In milk, the addition of this EO at the concentration of 0.1 microL/L did not influence its sensory properties, whereas at 1.0 microL/L, sensory properties were modified. In cheeses, the effect of adding EO into milk was studied in an experimental dairy plant allowing the production of small Cantal-type cheeses (10 kg) in 3 vats processed in parallel. The control (C) vat contained 110 L of raw milk; in the other 2 vats, 0.1 microL/L (EO1) or 3.0 microL/L (EO30) of EO were added to 110 L of the same milk. Six replicates were performed. After 5 mo of ripening, chemical and sensory analyses were carried out on the cheeses, including determination of the volatile compounds by dynamic headspace combined with gas chromatography-mass spectrometry. The EO did not influence the sensory properties of the cheeses at the lower concentration (EO1). However, the EO30 cheeses had a more intense odor and aroma, both characterized as "mint/chlorophyll" and "thyme/oregano." These unusual odors and aromas originated directly from the EO added. In total, 152 compounds desorbing from cheese were found, of which 41 had been added with the EO; in contrast, 54 compounds of the EO were not recovered in the cheese. Few volatile compounds desorbing from cheeses, other than the added compounds, were affected by EO addition. Among them, 2-butanol, propanol, and 3-heptanone suggested a slight effect of the EO on lipid catabolism. The antimicrobial activity of terpenes is not or is only marginally involved in the explanation of the influence of the botanical composition of the meadows on the pressed cheeses sensory properties. PMID:18096925

278

Produção de geléia de jambolão (Syzygium cumini Lamarck): processamento, parâmetros físico - químicos e avaliação sensorial/ Production of jambolan (Syzygium cumini Lamarck) jelly: processing, physical-chemical properties and sensory evaluation  

Abstract in portuguese A fruta jambolão (Syzygium cumini Lamarck) é uma fruta de coloração roxa intensa e sabor agradável. Dado que não há na literatura nenhum relato de seu aproveitamento industrial, a produção de geléia de jambolão tornou-se uma interessante atividade de pesquisa. Este trabalho objetivou a elaboração e a avaliação das características físico-químicas e sensoriais da geléia obtida do jambolão. A fruta apresentou a seguinte composição química: cinzas, 0,34 (more) %; lipídeos, 0,30%; proteínas, 0,67%; carboidratos, 10,07%; fibras, 0,28%; umidade, 87,75%; frutose, 0,4%; glicose, 0,6%; antocianinas totais, 0,276%; substâncias pécticas, 0,245%; acidez titulável, 5,91%; sólidos solúveis, 9,00%; e pH, 3,9. A geléia obtida apresentou a seguinte composição: açúcares redutores, 20,99%; não-redutores, 18,01%; açúcares totais, 39,00%; pH, 3,42; sólidos solúveis, 67ºBrix; acidez titulável, 5,47%; e umidade, 29,63%. A análise sensorial foi realizada por uma equipe de 50 provadores não treinados que avaliaram os atributos cor, aparência, odor, textura, sabor e avaliação global, pelo método de escala hedônica com nove pontos. Os resultados obtidos mostraram que o atributo cor foi o que mais agradou aos provadores, o atributo odor foi o menos apreciado. Em conclusão, o estudo de análise sensorial revelou uma aceitação satisfatória da geléia de jambolão. Abstract in english Jambolan (Syzygium cumini Lamarck) is a purple colored and very tasty fruit. Since there are no reports of its industrial use, the production of this jelly has become a matter of interest for research. The purpose of this work is to develop and evaluate the physical-chemical and sensory characteristics of the jelly made of jambolan. The fruit showed the following chemical composition: ash, 0.34%; lipids, 0.30%; proteins, 0.67%; carbohydrates, 10.07%; fibers, 0.28%; moistu (more) re, 87.75%; fructose, 0.4%; glucose, 0.6%; total anthocyanins, 0.276%; pectic substances, 0.245%; acidity (direct titration), 5.91%; soluble solids, 9.00% and pH 3.9. The jelly showed the following composition: reducing sugars, 20.99%; non-reducing, 18.01%; total sugars, 39.00%; pH, 3.42; soluble solids, 67 °Brix; acidity (direct titration), 5.47% and moisture, 29.63%. The sensory analysis was made by a non-trained-50 member panel who evaluated the color of the attributes, appearance, aroma, texture, taste and overall evaluation on a 9-point hedonic scale. The results showed that color was the most appreciated attribute while aroma was the least appreciated. In conclusion, the sensory analysis study revealed satisfactory acceptance of jambolan jelly.

279

Aroma compound analysis of Piper nigrum and Piper guineense essential oils from Cameroon using solid-phase microextraction-gas chromatography, solid-phase microextraction-gas chromatography-mass spectrometry and olfactometry.  

The investigation of aroma compounds of the essential oils of dried fruits of black pepper (Piper nigrum) and black and white "Ashanti pepper" (Piper guineense) from Cameroon by means of solid-phase microextraction (SPME) was carried out for the first time to identify the odorous target components responsible for the characteristic odor of these valuable spices and food flavoring products. By means of GC-flame ionization detection (FID) and GC-MS (using different polar columns) the main compounds (concentration >3.0%, calculated as area of GC-FID analysis using a non-polar fused-silica open tubular RSL-200 column) of the SPME headspace samples of P. nigrum (black) and P. guineense (black and white) were found to be: P. nigrum (black)--germacrene D (11.01%), limonene (10.26%), beta-pinene (10.02%), alpha-phellandrene (8.56%), beta-caryophyllene (7.29%), alpha-pinene (6.40%) and cis-beta-ocimene (3.19%); P. guineense (black)--beta-caryophyllene (57.59%), beta-elemene (5.10%), bicyclogermacrene (5.05%) and alpha-humulene (4.86%); and P. guineense (white)--beta-caryophyllene (51.75%), cis-beta-ocimene (6.61%), limonene (5.88%), beta-pinene (4.56%), linalool (3.97%) and alpha-humulene (3.29%). The most intense odor impressions of the essential oils of the various dried pepper fruits were given byprofessional perfumers as follows: P nigrum (black)--fine, pleasant black pepper note; P. guineense (black)--black pepper top-note; and P. guineense (white)--pleasant white pepper note. These analytical results for the SPME headspace samples of three different pepper species from Cameroon are in accordance with the olfactoric data of the corresponding essential oils. A GC-sniffing technique was used to correlate the single odor impression of the identified SPME headspace volatiles of the three investigated pepper samples with the following results: themain compounds such as beta-caryophyllene, germacrene D, limonene, beta-pinene, alpha-phellandrene and alpha-humulene, as well as minor constituents such as delta-carene, beta-phellandrene, isoborneol, alpha-guaiene, sarisan, elemicin, calamenene, caryophyllene alcohol, isoelemicin, T-muurolol, cubenol and bulnesol, are of greatest importance for the characteristic pepper odor notes of these three Piper samples. Further aroma impressions can be attributed to mono- and sesquiterpenes, hexane, octane and nonane derivatives. PMID:12462618

280

Vine balance: a study case in Carménère grapevines/ Balance del viñedo: un estudio de caso en un viñedo Carménère  

Abstract in spanish Vitis vinifera cv. Carménère es una variedad vigorosa que requiere alta acumulación de temperaturas y luminosidad para lograr una óptima madurez fenólica y disminuir sus aromas herbáceos lo cual ha implicado retrasar signifcativamente su fecha de cosecha en Chile. Esta investigación se desarrolló bajo la hipótesis que el manejo de follaje, el vigor y la carga podrían modifcar las relaciones vegetativo-productivas para adelantar o atrasar su madurez y conseguir e (more) l balance de viñedo. El objetivo de este estudio fue determinar el balance del viñedo y momento de madurez en viñedos Carménère. Se evaluaron diferentes niveles de vigor, poda y manejo de follaje. El estudio se llevó a cabo en el Valle Central de Chile en vides a pie franco, conducidas con cuatro cargadores, en espaldera simple vertical, localizada en suelos de alto potencial de crecimiento. La madurez pudo atrasarse con alto vigor y alta carga. Bajo estas condiciones se alcanzó una madurez temprana utilizando poda en pitones, bajo vigor y recurriendo también al raleo de racimos. Un adecuado balance de viñedo fue obtenido a partir de vides por bajo vigor y baja carga. Mediante un método gráfco es mostrado el balance de Carménère bajo estas condiciones de manejo. Abstract in english Vitis vinifera cv. Carménère is a vigorous variety of grapevine that requires high temperatures and luminosity for achieving optimal phenolic maturity and herbal aromas, which has been reported to signifcantly delay harvest in Chile. This research was developed under the hypothesis that canopy management, vigor and crop load could modify the productive and vegetative relationships for obtaining early or late ripening and achieving vine balance. The aim of this study was (more) to determine the vine balance and the time of ripeness for Carménère grapevines. Different vigor and canopy managements were evaluated. The study was conducted in the Central Valley of Chile during the 2007 to 2008 season with own-rooted Carménère vines trained to a four-cane vertical shoot position (VSP) located on high growth potential soil. The ripeness was delayed with high vigor and high crop load. In this growing condition, an early ripeness was reached with spur pruning, low vigor and by cluster thinning. In addition, the appropriate vine balance was only obtained in vines with low vigor and 50% cluster thinning. Together, these data demonstrate the vine balance of Carménère under these management conditions.

 
 
 
 
281

Estimativa do filocrono de morangueiro em sistemas consorciado e solteiro em ambientes protegidos/ Phyllochron estimation in intercropped strawberry and monocrop systems in a protected environment  

Abstract in portuguese O filocrono é definido como o tempo necessário para o aparecimento de folhas sucessivas em uma planta, caracterizando o crescimento e o desenvolvimento vegetal e, com isso, a adaptação da planta ao ambiente. Para verificar o desenvolvimento e a adaptação de cultivares de morangueiro consorciadas com a figueira, foi estimado o filocrono nesse sistema e no cultivo solteiro. O trabalho foi realizado em duas estufas agrícolas, na Universidade de Passo Fundo (28º15'41' (more) ' S, 52º24'45'' W e 709 m), no período de 08 de junho a 04 de setembro de 2009, compreendendo o período do transplante à 2ª floração. Avaliaram-se as cultivares Aromas, Camino Real, Albion, Camarosa e Ventana (mudas oriundas do Viveiro Agrícola LLahuen - Chile) e Festival, Camino Real e Earlibrite (mudas oriundas do Viveiro Viansa S.A. - Argentina) produzidas em sacolas de polietileno branco preenchidos com o substrato comercial Tecnomax®. Os tratamentos (cultivares) foram dispostos em delineamento de blocos ao acaso, com quatro repetições. Foi realizada uma regressão linear entre número de folhas (NF) na coroa principal e a soma térmica acumulada (STa). O filocrono (graus Celsius dia folha-1) foi estimado como sendo o inverso do coeficiente angular da regressão linear. Os dados foram submetidos à ANOVA e, quando houve significância, as médias foram comparadas pelo teste de Tukey (p Abstract in english The phyllochron is defined as the time required for the appearance of successive leaves on a plant; this characterises plant growth, development and adaptation to the environment. To check the growth and adaptation in cultivars of strawberry grown intercropped with fig trees, it was estimated the phyllochron in these production systems and in the monocrop. The experiment was conducted in greenhouses at the University of Passo Fundo (28º15'41'' S, 52º24'45'' W and 709 m) (more) from June 8th to September 4th, 2009; this comprised the period of transplant until the 2nd flowering. The cultivars Aromas, Camino Real, Albion, Camarosa and Ventana, which seedlings were originated from the Agrícola LLahuen Nursery in Chile, as well as Festival, Camino Real and Earlibrite, originated from the Viansa S.A. Nursery in Argentina, were grown in white polyethylene bags filled with commercial substrate (Tecnomax®) and evaluated. The treatments were arranged in a randomised block design and four replicates were performed. A linear regression was realized between the leaf number (LN) in the main crown and the accumulated thermal time (ATT). The phyllochron (degree-day leaf-1) was estimated as the inverse of the angular coefficient of the linear regression. The data were submitted to ANOVA, and when significance was observed, the means were compared using the Tukey test (p

282

Correlações entre características físico-químicas e sensoriais em suco de maracujá-amarelo (Passiflora edulis var. flavicarpa) durante o armazenamento/ Correlation between physico-chemical and sensory characteristcs of yellow passin fruit juice over storaging time  

Abstract in portuguese Foram estudadas possíveis correlações entre características físicas, químicas e sensoriais em suco de maracujá-amarelo (Passiflora edulis var. flavicarpa) submetido à pasteurização, durante o armazenamento por 120 dias, sob duas temperaturas (25 ± 5ºC e 5 ± 1ºC). As características físicas e químicas relacionadas a cor, parâmetros "L" (luminosidade), "a" (intensidade de vermelho e verde) e "b" (intensidade de amarelo e azul) de Hunter (more) , os açúcares redutores e não-redutores (sacarose, glucose e frutose), os compostos voláteis (butirato de etila, butirato de hexila, caproato de etila e caproato de hexila) e furfural foram correlacionadas com características sensoriais (homogeneidade da cor, cor laranja, aroma característico, aroma floral, aroma doce, sabor característico, sabor estranho, sabor oxidado, sabor cozido, gosto doce e gosto amargo) obtidas por Análise Descritiva Quantitativa. As correlações entre os parâmetros de cor e as características sensoriais de homogeneidade da cor e cor laranja foram baixas. Entretanto, o aumento da cor laranja foi proporcional ao aumento do valor "a" e inversamente proporcional aos valores "L" e "b". Correlações importantes foram observadas entre os compostos voláteis e sabor característico e aroma característico, aroma floral e aroma doce; furfural e sabor oxidado, sabor cozido e sabor estranho. Quanto aos açúcares redutores e não-redutores, enquanto observaram-se correlações significativas entre os teores de sacarose e o aroma doce, aroma floral, sabor característico e gosto doce, correlações significativas e positivas foram observadas entre os açúcares redutores e o sabor estranho e gosto amargo. De acordo com nossas observações, o uso de métodos instrumentais pode ser indicado, como a avaliação do escurecimento por meio de parâmetros colorimétricos de cor, sendo o valor "a" de Hunter, o melhor indicado. Abstract in english Physical-chemistry and sensory quality characteristics correlations were studied in yellow passion fruit juice (Passiflora edulis flavicarpa) submitted to thermal processing treatment, during 120 days of storage under two different temperatures. The color characteristics, Hunter 'L', 'a'and 'b'values, reducing sugars and non reducing sugars (sucrose, glucose and fructose), volatile compounds (ethyl butyrate, hexyl butyrate, ethyl caproate and hexyl caproate) and furfural (more) were correlated with sensory characteristics (juice homogeneity of color, orange color, characteristic aroma, floral aroma, sweet aroma, characteristic flavor, off flavor, oxidized flavor, cooked flavor, sweet taste and bitter taste) by Quantitative Descriptive Analysis. The color parameters and sensory characteristic correlations such as juice homogeneity of color and orange color, and a-value was proportional, instead ofL and b-values. Important correlations were observed between volatile compounds and characteristics flavor and aroma, sweet and floral aroma; furfural and oxidized, cooked and off flavor. The sucrose levels were statistically correlationated with sweet and floral aroma, characteristic flavor and sweet taste, while the reducing sugars were correlated with off flavor and bitter taste. From the results it can be concluded that the instrumental methods can be indicated, such as the browning color where colorimetric parameters like a-value is the best one.

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CARACTERIZACIÓN DE LOS COMPUESTOS VOLÁTILES ACTIVOS OLFATIVAMENTE EN UCHUVA (Physalisperuviana L.)/ CHARACTERIZATION OF ODOR-ACTIVE VOLATILES IN UCHUVA (Physalis peruviana L.)/ CARACTERIZAÇÃO DE COMPOSTOS VOLÁTEIS ATIVOS OLFATIVAMENTE EM UCHUVA (Physalis peruviana L.)  

Abstract in portuguese Durante o estudo de compostos olfativos ativos no aroma de uchuva (Physalis peruviana L.), foram identificados os compostos voláteis obtidos por três técnicas: extração líquido-líquido com pentano-diclorometano (1:1) (LL), Solvent-Assisted Flavor Evaporation (SAFE) e Heads-pace-Microextração em Fase Sólida (HS-MEFS). Também se acharam diferenças na qualidade do aroma dos extratos por meio de análise de olfatometria. A técnica SAFE permitiu a obtenção de um (more) extrato com um aroma semelhante à fruta fresca. Os compostos que apresentaram os maiores valores de fator de diluição de aroma (FD) foram: hexanal, 3-hidroxi-2-butanona, 2 metilpropanol, octanoato de etilo e 3-hidroxibutanoato de butilo. No extracto LL foram detectados alguns compostos sem atividade olfativa no fruto; em contrapartida, pela técnica de HS-MEFS não foi possível detectar todos os compostos ativos olfativamente, principalmente os de maior polaridade. Estes resultados mostram a utilidade do uso de uma nova abordagem para a análise de química do aroma, que dá mais importância á análise olfativa em estes estudos. Abstract in spanish Durante el estudio de los compuestos activos olfativamente en el aroma de la uchuva (Physalis peruviana L.) se identificaron los compuestos volátiles, obtenidos por 3 técnicas, extracción líquido-líquido con pentano-diclorometano (1:1) (LL), Solvent-Assisted Flavor Evaporation (SAFE) y í/eadspace-Microextracción en fase sólida (HS-MEFS), y se encontraron diferencias en la calidad del aroma de los extractos mediante el análisis olfato-métrico. La técnica SAFE pe (more) rmitió obtener un extracto con un aroma muy semejante al de la fruta fresca. Los compuestos que presentaron los valores más altos de factor de dilución de aroma (FD) fueron: hexanal, 3-hidroxi-2-butanona, 2-metil-propanol, 2-hidroxibutanoato de etilo, octanoato de etilo y 3-hidroxibutanoato de butilo. En el extracto LL se detectaron algunos compuestos sin actividad olfativa en la fruta; en contraste, mediante la técnica de HS-MEFS no fue posible detectar todos los compuestos activos olfativamente, principalmente los de mayor polaridad. Estos resultados muestran la utilidad del nuevo enfoque de análisis en química de aromas, el cual le da más relevancia al análisis olfativo en estos estudios. Abstract in english During the study of odor-active active compounds in the aroma of cape gooseberry (Physalis peruviana L.), volatile compounds obtained by three techniques-liquid liquid extraction with penta-ne-dichloromethane (1:1) (LL), Solvent-Assisted Flavor Evaporation (SAFE) and Headspace-Solid Phase Microextraction (HS-SPME) were identified. Differences in the aroma quality of the extracts were found by olfactometric analyses. The SAFE technique allowed obtain in ganextract with sim (more) ilar aroma to the freshfruit. Thecompounds with highest Flavor Dilution factor (FD) value were hexanal, 3-hydroxy-2-butanone, 2-methylpropanol, ethyl 2-hydroxybutanoate, ethyl octanoate, and butyl 3-hydroxybutanoate. Some compounds without olfactive activity in the fruit aroma were detected in the LL extract; in contrast, it was not possible todetectalloftheodor-activevolatilesby using HS-SPME technique, especially those of the most polarity. These results showtheutilityinusingthenewapproach of flavor chemistry analysis, which gives more relevance to the odor analysis during these studies.

284

QTL analysis of fruit quality in fresh market tomato: a few chromosome regions control the variation of sensory and instrumental traits.  

The organoleptic quality of tomato fruit involves a set of attributes (flavour, aroma, texture) that can be evaluated either by sensory analyses or by instrumental measures. In order to study the genetic control of this characteristic, a recombinant inbred line (RIL) population was developed from an intraspecific cross between a cherry tomato line with a good overall aroma intensity and an inbred line with medium flavour but bigger fruits. A total of 38 traits involved in organoleptic quality were evaluated. Physical traits included fruit weight, diameter, colour, firmness, and elasticity. Chemical traits were dry matter weight, titratable acidity, pH, and the contents of soluble solids, sugars, lycopene, carotene, and 12 aroma volatiles. A panel of trained assessors quantified sensory attributes: flavour (sweetness and sourness), aroma (overall aroma intensity, together with candy, lemon, citrus fruit, and pharmaceutical aromas) and texture (firmness, meltiness, mealiness, juiciness, and skin difficult to swallow). RILs showed a large range of variation. Molecular markers were used to map a total of 130 quantitative trait loci (QTL) for the 38 traits. They were mainly distributed in a few chromosome regions. Major QTLs (R(2) >30%) were detected for fruit weight, diameter, colour, firmness, meltiness, and for six aroma volatiles. The relationships between instrumental measures and sensory traits were analysed with regard to the QTL map. A special insight was provided about the few regions where QTLs are related to multiple traits. A few examples are shown to illustrate how the simultaneous analysis of QTL segregation for related traits may aid in understanding the genetic control of quality traits and pave the way towards QTL characterization. PMID:12324532

285

In vitro and in vivo release of aroma compounds from yellow-fleshed kiwifruit.  

Comparisons were made between the aroma volatiles of the yellow-fleshed kiwifruit, "Hort16A", at two different stages of eating ripeness: firm and soft. The firm fruit contained a small number of aroma compounds that the soft fruit did not contain. In general, however, the largest difference between the two firmness categories was in the levels of esters, with the soft fruit containing higher concentrations and a larger number of esters than the firm fruit. In vitro analysis directly after maceration using atmospheric pressure chemical ionization mass spectrometry (APCI-MS) showed the relative importance of the most intense aromas between fruit at the two different firmness stages and was used to compare the release rates of aromas. A comparison of the aroma concentrations from gas chromatography mass spectrometry (GC-MS) and APCI-MS headspace analyses showed that the APCI-MS headspace showed less bias toward enzymatically generated lipid degradation compounds. A GC-sniffing study showed that many of the most intense compounds, acetaldehyde, hexanal, ethyl butanoate, and (E)-2-hexenal but not ethanol, showed odor activity in macerated fruit. In addition, dimethyl sulfide (DMS), a volatile present at very low levels in the fruit, also appeared to be an important contributor to the odor. In vivo analyses also showed much higher levels of aroma compounds in the soft fruit compared to the firm fruit, with evidence of persistence of some compounds, including DMS. There were a number of similarities between the breath profiles of the two panelists, which confirmed the importance of DMS in "Hort16A" aroma. PMID:17616207

286

Isolation, expression, and characterization of a 13-hydroperoxide lyase gene from olive fruit related to the biosynthesis of the main virgin olive oil aroma compounds.  

A full-length cDNA clone (OepHPL) coding for hydroperoxide lyase was isolated from olive fruit ( Olea europaea cv. Picual). The deduced amino acid sequence shows significant similarity to known plant hydroperoxide lyases and contains a N-terminal sequence that displays structural features of a chloroplast transit peptide. Genomic Southern blot analysis indicates that at least one copy of OepHPL is present in the olive genome. The recombinant hydroperoxide lyase was specific for 13-hydroperoxide derivatives of linolenic and linoleic acids but did not use 9-hydroperoxy isomers as substrates. Analyses of reaction products revealed that this enzyme produces primarily (Z)-hex-3-enal, which partially isomerizes to (E)-hex-2-enal, from 13-hydroperoxylinolenic acid and hexanal from 13-hydroperoxylinoleic acid. Expression levels were measured in different tissues of Picual and Arbequina varieties, including mesocarp and seed during development and ripening of olive fruits. The involvement of this olive hydroperoxide lyase gene in the biosynthesis of virgin olive oil aroma compounds is discussed. PMID:20334343

287

Functional characterization of two 13-lipoxygenase genes from olive fruit in relation to the biosynthesis of volatile compounds of virgin olive oil.  

Two LOX cDNA clones, Oep1LOX2 and Oep2LOX2, have been isolated from olive ( Olea europaea cv. Picual). Both deduced amino acid sequences showed significant similarity to known plant LOX2, and they contain an N-terminal chloroplastic transit peptide. Genomic Southern blot analyses suggest that at least three copies of Oep1LOX2 and one copy of Oep2LOX2 should be present in the olive genome. Linolenic acid proved to be the preferred substrate for both olive recombinant LOXs, and analyses of reaction products revealed that both enzymes produce primarily 13-hydroperoxides from linoleic and linolenic acids. Expression levels of both genes were measured in the mesocarp and seeds during development and ripening of Picual and Arbequina olive fruit along with the level of volatile compounds in the corresponding virgin olive oils. Biochemical and gene expression data suggest a major involvement of the Oep2LOX2 gene in the biosynthesis of virgin olive oil aroma compounds. PMID:19722522

288

Chemical Profiling and Gene Expression Profiling during the Manufacturing Process of Taiwan Oolong Tea “Oriental Beauty”  

Oriental Beauty, which is made from tea leaves infested by the tea green leafhopper (Jacobiasca formosana) in Taiwan, has a unique aroma like ripe fruits and honey. To determine what occurs in the tea leaves during the oolong tea manufacturing process, the gene expression profiles and the chemical profiles were investigated. Tea samples were prepared from Camellia sinensis var. sinensis cv. Chin-shin Dah-pang while the tea leaves were attacked by the insect. The main volatile compounds, such as linalool-oxides, benzyl alcohol, 2-phenylethanol, and 2,6-dimethylocta-3,7-diene-2,6-diol, increased during manufacture. The gene expression profiles during manufacture were analyzed by differential screening between fresh leaves and tea leaves of the first turn over. Many up-regulated transcripts were found to encode various proteins homologous to stress response proteins. Accordingly, the endogenous contents of abscisic acid and raffinose increased during manufacture. Thus the traditional manufacturing method is a unique process that utilizes plant defense responses to elevate the production of volatile compounds and other metabolites.   

289

Effect of the partial replacement of sodium chloride by other salts on the formation of volatile compounds during ripening of dry-cured ham.  

The effect of the partial NaCl replacement by other salts (potassium, calcium, and magnesium chloride) on the formation of volatile compounds through the processing of dry-cured ham was studied using solid-phase microextraction (SPME). Three salt formulations were considered, namely, I (100% NaCl), II (50% NaCl and 50% KCl), and III (55% NaCl, 25% KCl, 15% CaCl(2), and 5% MgCl(2)). There was an intense formation of volatile compounds throughout the processing of dry-cured hams, particularly during the "hot-cellar" stage. The differences between treatments were found to be more remarkable at the end of the curing process. Hams from formulations I and II had significantly higher amounts of lipid-derived volatiles such as hexanal than hams from formulation III, whereas the latter had significantly higher amounts of Strecker aldehydes and alcohols. Plausible mechanisms by which salt replacement may affect the generation of volatile compounds include the influence of such replacement on lipid oxidation and proteolysis phenomena. The potential influence of the volatiles profile on the aroma of the products is also addressed in the present paper. PMID:22804717

290

Effect of the inoculation level of Lactobacillus acidophilus in probiotic cheese on the physicochemical features and sensory performance compared with commercial cheeses.  

The complex metabolism of probiotic bacteria requires several technological options to guarantee the functionally of probiotic dairy foods during the shelf life. This research aimed to evaluate the effect of the supplementation of increasing amounts of Lactobacillus acidophilus (0, 0.4, or 0.8 g/L of milk) on the physicochemical parameters and sensory acceptance of Minas fresh cheese. In addition, the sensory acceptance of probiotic cheeses was assessed using a consumer test and compared with commercial cheeses (conventional and probiotic). High counts (9.11 to 9.42 log cfu/g) of L. acidophilus were observed throughout the shelf life, which contributed to the maintenance of its probiotic status and resulted in lower pH values and greater production of organic acids. The probiotic cheeses presented lower scores for appearance, aroma, and texture compared with conventional cheeses. Internal preference mapping explained almost 60% of the total variation of the data and showed a large number of consumers concentrated near the conventional cheeses, demonstrating greater preference for these samples. The findings indicated that some negative sensory effects could occur when high level of supplementation with L. acidophilus is used in probiotic cheese processing. PMID:21943729

291

Mutagenicity testing in the Salmonella typhimurium assay of phenolic compounds and phenolic fractions obtained from smokehouse smoke condensates  

Smokehouse smoke, which is used for flavouring meat products, was investigated for its mutagenic activity in the Salmonella typhimurium assay. We were chiefly concerned with the fractions free of polycyclic aromatic hydrocarbons but containing phenol compounds, which are responsible for the preservative and aromatizing properties of the smoke. The most abundantly occurring phenol compounds (phenol, cresols, 2,4-dimethylphenol, brenzcatechine, syringol, eugenol, vanilline and guaiacol) gave negative results when they were tested for mutagenicity at five concentrations up to 5000 micrograms/plate, with and without S-9 mix, using five strains of S. typhimurium. Even when phenol was further investigated in a variety of test conditions, no induction of his+ revertants was observed. When smokehouse smoke was condensed and fractionated the majority of the various phenolic fractions also gave negative results when tested at five concentrations using five strains of S. typhimurium. However there was a slight increase in the number of revertants in a few cases. The presence in the phenolic fractions of very small amounts of mutagenic impurities, the nature of which needs further investigation, cannot be excluded. These results support the further development of non-hazardous smoke-aroma preparations, based on the phenolic components of smokehouse smoke.

292

The Nose Knows: Biotechnological Production of Vanillin  

Vanillin, the compound responsible for the well-known vanilla aroma, is almost exclusively produced via a chemical process, with only a small fraction extracted from natural sources, namely, the bean of the orchid "Vanilla planifolia". Research is being done towards a green chemistry process to obtain natural vanillin. A model biotechnological process is described that exposes students to the essentials of a greener, chemoenzymatic synthesis of vanillin in a multiday laboratory experiment. Bacterial expression was utilized to produce the enzyme eugenol oxidase (EUGO), which was purified from cell extracts using inexpensive gravity-flow ion-exchange chromatography, and was highly visual due to the bright yellow color of the enzyme caused by its covalently-bound flavin cofactor. Students evaluated its purity with SDS-PAGE and a purification table and measured its kinetic parameters with UV-vis spectrophotometry. Vanillin was produced by EUGO through the enzymatic oxidation of vanillyl alcohol. Because of its highly visual and olfactory nature, this is an ideal experiment to expose undergraduate students to the basic principles of a biotechnological process, enzyme production and purification and elementary enzyme kinetics. (Contains 1 table and 4 figures.)

293

Changes in the transcriptome of 'Mor' mandarin flesh during storage: emphasis on molecular regulation of fruit flavor deterioration.  

Mandarin sensory acceptability deteriorates rapidly after harvest. To gain a better understanding of the molecular processes that occur in 'Mor' mandarin flesh and contribute to flavor deterioration during storage, we performed genome-wide transcriptional profiling analysis using the Affymetrix Citrus GeneChip. Out of 30,171 probe sets representing citrus transcripts on the microarray, expression of 1,139 probe sets was significantly (q ? 0.01) altered by factors of at least 4 after 6 weeks of cold storage at 5 °C, of which 745 (65%) were downregulated and 394 (35%) upregulated. Overall, storage led to expression arrest of general cellular and metabolic activity, but enhanced lipid and amino acid catabolism, most probably to form substrates for the tricarboxylic acid (TCA) cycle and energy production. In addition, storage enhanced gene expression of pyruvate decarboxylase (PDC), a key enzyme in anaerobic respiration and the ethanol fermentation pathway. Taken together, we propose that induction of amino acids and fatty acids degradation leads to accumulation of volatiles involved in formation of "fruity" (overripe) and "musty" aromas, respectively, whereas induction of ethanol fermentation metabolism leads to formation of "alcohol" flavor, all of which generate off-flavors after harvest. PMID:21401120

294

Implications and trends of siloxanes in landfill and wastewater biogases[General Conference  

The energy value of biogas generated in digesters at wastewater treatment facilities or at sanitary landfills was discussed with particular reference to the presence of siloxane in the biogas. The high methane component of biogas from both sources renders them suitable for energy utilization, including electricity production. However, biogas from these sources contain carbon dioxide and trace compounds such as sulfides and other organic substances that can be harmful to combustion devices and air pollution control equipment. Some of the problem causing substances include volatile methylsiloxanes (VMS) and linear polydimethyls (PDM). As a popular aroma-free environmental cleaner, VMS solvents are widely available from natural sources, and are exempt from volatile organic compounds regulations. Typical uses include skin cream and stick deodorants. Siloxanes are also common components in shampoos, cosmetics, detergents, pharmaceuticals, ink, lubricants and adhesives. Although siloxanes have a high molecular weight, they also have relatively high vapor pressures and low water solubilities. Therefore, they are inclined to move from water to the biogas generated under anaerobic conditions in wastewater digesters and landfills. Wastewater digesters appear to have a higher siloxane content because of the higher temperatures in the digesters. The consequence of burning biogas containing siloxanes is excessive wear on gas motor surfaces due to the abrasive action of the silica ash. This silica ash accelerates the wear of the engine's physical components, and fouls air pollution control equipment.

295

Funcionalidade da oleoresina de páprica microencapsulada em goma-arábica e amido de arroz/gelatina/ Functionality of microencapsulated paprika oleoresin in arabic gum and rice starch/gelatin  

Abstract in portuguese O objetivo deste trabalho foi avaliar a funcionalidade da oleoresina de páprica microencapsulada em goma-arábica e amido de arroz/gelatina, incorporada nos sistemas-modelo bolo e gel de gelatina. Avaliou-se a cor por meio de medida instrumental e aceitação sensorial por atributos de aparência e aceitação global. O pigmento encapsulado solubilizou-se, tingiu e se distribuiu uniformemente nos bolos, os quais apresentaram boa aceitação global. Nos géis, a goma apre (more) sentou desempenho superior ao amido/gelatina quanto à aparência, porém, todos os tratamentos obtiveram baixa aceitação global. A presença da oleoresina microencapsulada não interferiu negativamente no sabor, aroma ou textura dos sistemas analisados. Abstract in english The objective of this work was to evaluate the functionality of microencapsulated paprika oleoresin in arabic gum and rice starch/gelatin incorporated into the model systems: cake and gelatin gel. The systems were evaluated by instrumental color and consumer test based on the appearance and global acceptance attributes. The encapsulated pigment successfully dyed the cakes as well as was uniformly distributed into the products, showing good sensory acceptance. In the gels, (more) a superior performance was obtained when using arabic gum, however all treatments applied for gels showed low global sensory acceptance. The presence of microencapsulated paprika oleoresin had no negative effect on taste, flavor or texture of analyzed systems.

296

Chemical Characteristics and Volatile Profile of Genetically Modified Peanut Cultivars  

Genetic engineering has been used to modify peanut cultivars for improving agronomic performance and pest resistance. Food products developed through genetic engineering have to be assessed for their safety before approval for human consumption. Preservation of desirable chemical, flavor and aroma attributes of the peanut cultivars during the genetic modifications is critical for acceptance of genetically modified peanuts (GMP) by the food industry. Hence, the main objective of this study is to examine chemical characteristics and volatile profile of GMP. The genetically modified peanut cultivars, 188, 540 and 654 were obtained from the USDA-ARS in Stillwater, Oklahoma. The peanut variety Okrun was examined as a control. The volatile analysis was performed using a gas chromatograph/mass spectrometer (GC/MS) equipped with an olfactory detector. The peanut samples were also analyzed for their moisture, ash, protein, sugar and oil compositions. Experimental results showed that the variations in nutritional composition of peanut lines examined in this study were within the values reported for existing cultivars. There were minor differences in volatile profile among the samples. The implication of this study is significant, since it shows that peanut cultivars with greater pest and fungal resistance were successfully developed without major changes in their chemical characteristics.   

297

Design and control of energy efficient food drying processes with specific reference to quality; evaluation of physical and quality changes in foods during drying  

The ultimate goal of the project is to develop procedures, techniques, data and other information that will aid in the design of cost effective and energy efficient drying processes that produce high quality foods. This objective has been sought by performing studies to determine the pertinent properties of food products, by developing models to describe the fundamental phenomena of food drying and by testing the models at laboratory scale. Finally, this information is used to develop recommendations and strategies for improved dryer design and control. This volume emphasizes a detailed literature review and several extensive experimental studies. Since the basic principle of food dehydration is the removal of water from food, the process of removing water causes quality changes which can be categorized as physical, chemical, and nutritional. These changes often have adverse effects on the quality of the resulting dehydrated food. In this work, the types of physical and chemical changes common in food drying and the important factors for them were reviewed. Pertinent kinetic models and kinetic data reported in literature were also collected and compiled as the results of review study. The overall objectives of this study were to identify major quality change in foods caused by drying process and to get the knowledge of the relationship between the quality change and factors known to affect them. The quality parameters reviewed included: browning, lipid oxidation, color loss, shrinkage, solubility, texture, aroma and flavor, vitamin and protein loss and microbiological concerns. 54 refs., 74 figs., 49 tabs.

298

Changes in the Physical and Chemical Properties of Thai Brown Rice Caused by High-Temperature Treatment  

The market for healthy food in Thailand is increasing rapidly due to growing recognition that food ingredients can causes diseases such as cancer and type 2 diabetes. Healthy food from natural products, and especially from whole grains such as brown rice, has become a priority for Thai consumers. Brown rice is rich in nutrients such as fiber and vitamins. However, brown rice has a high glycemic index and is therefore not suitable for patients with type 2 diabetes, since blood sugar and insulin levels increase rapidly after ingestion of this rice. The Khao Dok Mali 105 cultivar of brown rice has a low amylose content (12% to 17% by weight), and is popular in Thailand because of its flavor, aroma, and soft texture. However, cultivars such as Phisanurok 3 and Suphan Buri 1 with high starch amylose contents (23% to 26% by weight) are also in demand. Thai rice varieties normally contain degrees of crystallinity of A-type amylose, with a medium to fast digestion rate. Recently, researchers found that hig-temperature treatment (130 to 150°C) influenced the glycemic index of brown rice. Gelatinization was produced during the processing, and affected physical and chemical properties such as texture and starch digestibility. The processing decreased the degree of crystallinity (i.e., increased the proportion of V-type amylose) and produced amylose-lipid complexes in the brown rice, which slow digestion of the starch. Our study is the first to confirm these previous results for three popular Thai rice cultivars.   

299

Studies on the reconstruction of D{sup *{+-}} mesons in photoproduction at the H1 detector at HERA; Untersuchung zur Rekonstruktion von D{sup *{+-}}-Mesonen in Photoproduktion am H1-Detektor bei HERA  

In electron-proton collisions at the HERA collider ring of DESY charmed particles, especially charged excited D-mesons, are produced via the process of boson gluon fusion, their decay particles being detected in the H1 detector. In this thesis the cross section for the production of these charmed mesons is determined, which leads to a better understanding of the gluon density in the proton. In order to calculate the cross section, the following decay channel is analysed: The charged excited D-Meson decays into an uncharged D-Meson and a slow charged pion. The first decays into an uncharged K-Meson and two pions of opposite charge. The K-Meson itself decays into another pair of pions of opposite charge, so that all together five charged pions are produced. The charged excited D-Meson is reconstructed from these five pions. This analysis is based on the data of the H1 detector collected in the running periods of the years 1997, 1999 and 2000. The data is compared to predictions of the Monte Carlo generator AROMA 2.2, which offers a good description of the underlying generation processes as well as the decay processes.

300

Coke production. [Part of the charge added as briquets to increase the density of the charge and durability of the coke  

Free burning coal less than or equal to 90 percent by weight and greater than or equal to 10 percent binder are combined at a temperature higher than the softening point of the binder. Varying the ratio of the compound's components produces briquets of varying durability. The briquets are added to the burden to be coked in conventional chamber furnaces. High polymeric bituminous material with a high aroma is chosen as the binder. The moisture content of the blended coals should be less than 4 percent by weight. During loading into the coking chamber, the majority of the less-durable briquets disintegrated into pieces of varying size. The blend of the mixture, whole and decomposed briquets, has a high density and makes possible the production of highly durable blast furnace coke. More than 50 percent briquets can be added into the mixture. In the example given, the mixture's density was 758-957 kg/m/sup 3/, while the durability of the DI/sub 15//sup 30/ coke was 92.1 to 93.7 percent.

 
 
 
 
301

The impact of co-inoculation with Oenococcus oeni on the trancriptome of Saccharomyces cerevisiae and on the flavour-active metabolite profiles during fermentation in synthetic must.  

Co-inoculation of commercial yeast strains with a bacterial starter culture at the beginning of fermentation of certain varietal grape juices is rapidly becoming a preferred option in the global wine industry, and frequently replaces the previously dominant sequential inoculation strategy where bacterial strains, responsible for malolactic fermentation, are inoculated after alcoholic fermentation has been completed. However, while several studies have highlighted potential advantages of co-inoculation, such studies have mainly focused on broad fermentation properties of the mixed cultures, and no data exist regarding the impact of this strategy on many oenologically relevant attributes of specific wine yeast strains such as aroma production. Here we investigate the impact of co-inoculation on a commercial yeast strain during alcoholic fermentation by comparing the transcriptome of this strain in yeast-only and in co-inoculated fermentations of synthetic must. The data show that a significant number of genes are differentially expressed in this strain in these two conditions. Some of the differentially expressed genes appear to respond to chemical changes in the fermenting must that are linked to bacterial metabolic activities, whereas others might represent a direct response of the yeast to the presence of a competing organism. PMID:22029926

302

Cloning and characterisation of a cystathionine ?/?-lyase from two Oenococcus oeni oenological strains.  

Sulphur-containing compounds in wine have been extensively studied because of their effect on wine flavour and quality. In this study, an enzyme that degrades sulphur-containing amino acids was cloned and characterised from two Oenococcus oeni strains of oenological origins. The enzyme has features of a cystathionine-?-lyase (EC 4.4.1.1), a pyridoxal-5-phosphate-dependent enzyme catalysing an ?,?-elimination reaction of L: -cystathionine to produce L: -cysteine, ?-ketobutyrate and ammonia. Moreover, it was able to catalyse an ?,?-elimination reaction producing homocysteine, pyruvate and ammonia from L: -cystathionine. An elimination reaction of L: -cysteine and DL: -homocysteine was also efficiently catalysed by the enzyme, resulting in the formation of hydrogen sulphide. Furthermore, the ability to demethiolate methionine into methanethiol, an unfavourable volatile sulphur compound in terms of wine aroma, was observed. The findings of this work suggest that O. oeni seems to play a minor role in the production of volatile sulphur compounds during the vinification process as the optimal conditions were far from the harsh wine environment. PMID:20922375

303

Inhibitory effects of spice essential oils on the growth of Bacillus species.  

A series of essential oils of 11 Turkish plant spices [black thyme, cumin, fennel (sweet), laurel, marjoram, mint, oregano, pickling herb, sage, savory, and thyme], used in foods mainly for their flavor, aromas, and preservation, in herbal tea, in alternative medicines, and in natural therapies, were screened for antibacterial effects at 1:50, 1:100, 1:250, and 1:500 dilutions by the paper disc diffusion method against six Bacillus species (Bacillus amyloliquefaciens ATCC 3842, Bacillus brevis FMC 3, Bacillus cereus FMC 19, Bacillus megaterium DSM 32, Bacillus subtilis IMG 22, and B. subtilis var. niger ATCC 10). All of the tested essential oils (except for cumin) showed antibacterial activity against one or more of the Bacillus species used in this study. Generally, the essential oils at 1:50 and 1:100 levels were more effective. Only one essential oil (laurel) was not found effective against the tested bacteria. The bacterium most sensitive to all of the spice essential oils was B. amyloliquefaciens ATCC 3842. Based on the results of this study, it is likely that essential oils of some spices may be used as antimicrobial agents to prevent the spoilage of food products. PMID:17004909

304

Identification and partial characterization of extracellular aspartic protease genes from Metschnikowia pulcherrima IWBT Y1123 and Candida apicola IWBT Y1384.  

The extracellular acid proteases of non-Saccharomyces wine yeasts may fulfill a number of roles in winemaking, which include increasing the available nitrogen sources for the growth of fermentative microbes, affecting the aroma profile of the wine, and potentially reducing protein haze formation. These proteases, however, remain poorly characterized, especially at genetic level. In this study, two extracellular aspartic protease-encoding genes were identified and sequenced, from two yeast species of enological origin: one gene from Metschnikowia pulcherrima IWBT Y1123, named MpAPr1, and the other gene from Candida apicola IWBT Y1384, named CaAPr1. In silico analysis of these two genes revealed a number of features peculiar to aspartic protease genes, and both the MpAPr1 and CaAPr1 putative proteins showed homology to proteases of yeast genera. Heterologous expression of MpAPr1 in Saccharomyces cerevisiae YHUM272 confirmed that it encodes an aspartic protease. MpAPr1 production, which was shown to be constitutive, and secretion were confirmed in the presence of bovine serum albumin (BSA), casein, and grape juice proteins. The MpAPr1 gene was found to be present in 12 other M. pulcherrima strains; however, plate assays revealed that the intensity of protease activity was strain dependent and unrelated to the gene sequence. PMID:22820332

305

Postharvest temperature influences volatile lactone production via regulation of acyl-CoA oxidases in peach fruit.  

The biosynthesis of volatile compounds in plants is affected by environmental conditions. Lactones are considered to be peach-like aroma volatiles; however, no enzymes or genes associated with their biosynthesis have been characterized. White-fleshed (cv. Hujingmilu) and yellow-fleshed (cv. Jinxiu) melting peach (Prunus persica L. Batsch) fruit were used as materials in two successive seasons and responses measured to four different temperature treatments. Five major lactones accumulated during postharvest peach fruit ripening at 20?°C. Peach fruit at 5?°C, which induces chilling injury (CI), had the lowest lactone content during subsequent shelf life after removal, while 0?°C and a low-temperature conditioning (LTC) treatment alleviated development of CI and maintained significantly higher lactone contents. Expression of PpACX1 and activity of acyl-CoA oxidase (ACX) with C16-CoA tended to increase during postharvest ripening both at 20?°C and during shelf life after removal from cold storage when no CI was developed. There was a positive correlation between ACX and lactones in peach fruit postharvest. Changes in lactone production in response to temperatures are suggested to be a consequence of altered expression of PpACX1 and long-chain ACX activity. PMID:21951070

306

Expression of POX2 gene and disruption of POX3 genes in the industrial Yarrowia lipolytica on the ?-decalactone production.  

The yeast Yarrowia lipolytica growing on methyl ricinoleate can produce ?-decalactone, the worthy aroma compound, which can exhibit fruity and creamy sensorial notes, and recognized internationally as a safe food additive. Unfortunately, the yield is poor because of lactone degradation by enzyme Aox3 (POX3 gene encoded), which was responsible for continuation of oxidation after C(10) level and lactone reconsumption. In this paper, we chose the industrial Y. lipolytica (CGMCC accession number 2.1405), which is the diploid strain as the starting strain and constructed the recombinant strain Tp-12 by targeting the POX3 locus of the wild type, one copy of POX3 was deleted by CRF1+POX2 insertion. The other recombinant strain Tpp-11, which was a null mutant possessing multiple copies of POX2 and disrupted POX3 genes on two chromosomes, was constructed by inserting XPR2+hpt into the other copy of POX3 of Tp-12. The growth ability of the recombinants was changed after genetic modification in the fermentation medium. The production of ?-decalactone was increased, resulting from blocking ?-oxidation at the C(10) Aox level and POX2 overexpression. The recombinant strain Tpp-11 was stable. Because there was no reconsumption of ?-decalactone, the mutant strain could be grown in continuous fermentation of methyl ricinoleate to produce ?-decalactone. PMID:22115771

307

Estudo cinético da obtenção de ésteres utilizando enzima lipozyme TL IM como catalisador/ Kinetic study of the production of the aliphatic ester n-amyl octanoate by direct esterification using the enzyme Lipozyme TL IM as catalyst  

Abstract in portuguese Nesse trabalho foi estudada a produção do éster alifático octanoato de n-pentila por esterificação direta usando a enzima Lipozyme TL IM como catalisador, sendo esse éster usado como aroma na indústria de alimentos. Foi verificada a influência da concentração inicial de substratos na velocidade inicial da reação, sendo esta determinada através do consumo de ácido octanoico ao longo do tempo. Modelos cinéticos clássicos descritos na literatura não se ajus (more) taram bem aos dados experimentais. A máxima velocidade da reação foi alcançada a 40 ºC. A enzima Lipozyme TL IM sofre inibição por substrato Abstract in english In this work, the production of the aliphatic ester n-amyl octanoate by direct esterification using the enzyme Lipozyme TL IM as catalyst was studied. The influence of the initial concentration of the substrate on the initial rate of reaction was verified. The initial rate of the reaction was determined by the octanoic acid consumption over time. The kinetic models described in the literature did not fit to the experimental data. The maximum rate was reached at 40 ºC. Lipozyme TL IM was inhibited by the initial concentration of the substrate

308

New Green Tea Cultivar 'Yumewakaba' which Quality is High on Aroma and Taste by Slight Half Fermentation of Leaves.  

New green tea cultivar‘Yumewakaba’has been bred at the Green Tea and Local Products Laboratory of Saitama Prefectural Agriculture and Forestry Research Center. The clone was crossed between‘Yabukita’and Saitama No.9’in 1968. Local adaptability, tolerance to bark split frost injury, and Blister blight were tested at 17 prefectural tea experiment stations from 1994 to 2002. It was registered as ‘Norin No.53’and named ‘Yumewakaba’in 20The characteristics of the cultivar are as follows The shape of the cultivar is erect type, and spread of tea bush is the same as‘Yabukita’.The size of mature leaves are smaller than those of ‘Yabukita’. Immature leaves are lustrougreen and soft. The rooting ability of nursery plants are high and taking roots after planting is good. The plucking time of the first crop of this cultivar in Saitama is 1 or 2 days later than that of ‘Yabukita’.‘Yumewakaba’is middle budding cultivar. The yield of 1st or 2nd crop is the same that of‘Yabukita. ‘Yumewakaba’is resistance to cold drought and bark split frost injury. Thlevel of resistance to freezing injur y is stronger than that of ‘Yabukita’ The damage Anthracnose is less than that of ‘Yabukita. The appearance is better than that of ‘Yabukita’, and the quality of liquor is the same as ‘Yabukita’. The quality of processed goods from slightly half fermented leaves of this cultivar is high on the aroma and the taste. ‘Yumewakaba’is suitable for northern tea producing areas, and cool semi-mountainousareas.

309

A fermented meat model system for studies of microbial aroma formation  

A fermented meat model system was developed, by which microbial formation of volatiles could be examined The model was evaluated against dry, fermented sausages with respect to microbial growth, pH and volatile profiles. Fast and slowly acidified sausages and models were produced using the starter cultures Pediococcus pentosaceus and Staphylococcus xylosus. Volatiles were collected and analysed by dynamic headspace sampling and GC MS. The analysis was primarily focused on volatiles arising from amino acid degradation and a total of 24 compounds, of which 19 were quantified, were used for multivariate data analysis. Growth of lactic acid bacteria was comparable for model and sausages, whereas survival of S. xylosus was better in the model. Multivariate analysis of volatiles showed that differences between fast and slowly acidified samples were identical for model and sausage. For both sausage and model, fast-acidified samples had a high content of ketones, sulphides and methyl-branched acids, whereas slowly acidified samples had the highest content of methyl-branched alcohols, aldehydes, their ethyl esters, phenylacetaldehyde and methional. Furthermore, model repeatability with respect to pH, microbial growth and volatile profiles was similar to sausage production. Based on these findings, the model system was considered valid for studies of aroma formation of meat cultures for fermented sausage.

310

ACEPTABILIDAD Y CONSUMO DE UNA BEBIDA LÁCTEA CON OMEGA-3 EN EMBARAZADAS Y NODRIZAS DEL PROGRAMA NACIONAL DE ALIMENTACIÓN COMPLEMENTARIA/ ACCEPTABILITY AND CONSUMPTION OF A DAIRY DRINK WITH OMEGA-3 IN PREGNANT AND LACTATING WOMEN OF THE NATIONAL SUPPLEMENTARY FOOD PROGRAM  

Abstract in spanish Antecedentes: el Ministerio de Salud incorporó el año 2008 en el Programa Nacional de Alimentación Complementaria una bebida láctea para embarazadas y mujeres en lactancia, fortificada con EPA y DHA. El producto presentó inicialmente algún grado de rechazo en la población, lo que motivó modificar sus características organolépticas. Objetivo: evaluar en una muestra nacional la aceptabilidad y consumo de la 'Purita Mama" modificada, un año después de iniciar su (more) distribución. Metodología: muestra aleatoria de 1.272 beneficiarías en 62 Consultorios y 21 Postas Rurales, de todo el país. Se aplicó una encuesta semi estructurada para evaluar retiro, aceptabilidad y consumo por las beneficiarías y otros miembros del hogar. Resultados: El 90,7% de las madres retiraba regularmente el producto. Se observaron importantes problemas en la preparación de Purita Mamá, por baja dilución (22%) o excesiva concentración (50,8%). La apreciación global del producto presentó una mediada de 3 en escala de 1 a 5 (regular) en embarazadas y nodrizas, destacando opiniones negativas respecto al excesivo dulzor (19,2%) y aroma fuerte (49,9%). La mediana de consumo de las embarazadas fue 250 mL/día, cercano a lo programado y algo superior en las nodrizas, aunque reciben mayor cantidad. El 86% de las madres valora positivamente las características nutricionales del producto para la madre o su hijo. Cerca del 60% de las madres no comparte la bebida láctea, lo que indica una dilución intrafamiliar relativamente baja. Conclusiones: no hubo un cambio importante en el nivel de aceptabilidad del producto y los niveles de consumo fueron relativamente adecuados. Es importante reforzar la información sobre la forma de preparar el producto, proponer diferentes alternativas de preparación y eventualmente considerar alternativas de sabor. Abstract in english Background: The Ministry of Health incorporated in 2008 in the national supplementary feeding program a milk based drink for pregnant and nursing women fortified with EPA and DHA. The product initially presented some degree of rejection in the population, which led to modify its organoleptic characteristics. Objective: To evaluate in a national sample the acceptability and consumption of the modified product a year after starting distribution. Methodology: Random sample o (more) f1,272 beneficiaries in 62 clinics and 21 rural health posts across the country. A semistructured survey to assess withdrawal, acceptability and consumption by the beneficiary and other household members was applied. Results: Ninety point seven %% of mothers regularly withdrew the product. There were important problems in the preparation of "Purita Mama" by lower dilution (22%) or excessive concentration (50.8%). The overall assessment of the product showed an average of 3 (regular) on a scale of 1 to 5 in pregnant and lactating women, highlighting negative opinions about the excessive s weetness (19.2%) and strong aroma (49.9%). The median overall assessment of the mothers was 3 (regular) on a scale of 1 to 5, without significant differences between pregnant and lactating women. The median consumption of the beneficiaries was 250 ml/day, close to schedule and higher in the nursing women, although they receive more product. Eighty % of mothers appreciate the nutritional benefits of the product to the mother or child. About 60% of mothers do not share the milk drink, which indicates a relatively low domestic dilution. Conclusions: there was no significant change in the level of acceptability of the product and the consumption levels were relatively adequate. It is important to enhance information on how to prepare the product, to propose different alternatives for consumption and eventually to consider alternatives of flavor.

311

Processamento de achocolatado de cupuaçu por spray-dryer/ Cupuassu chocolate drink powder processed by spray-dryer  

Abstract in portuguese O achocolatado de cupuaçu é uma mistura do pó de cupuaçu, açúcar, aroma e outros ingredientes constantes da formulação. Este produto formulado foi processado por spray-dryer, gerando um produto seco, pulverizado e instantaneizado. O achocolatado acrescido de água (concentrado) passa pelo spray-dryer formando glóbulos de pequeno diâmetro que são arrastados por uma corrente de ar quente. A rápida evaporação de líquido permite manter baixa a temperatura do ar (more) na secagem, não afetando o produto. O pó de cupuaçu não dispersa prontamente em água devido ao seu conteúdo de óleo. Conseqüentemente, necessita-se de uma forma desengordurada para se obter instantaneização. A secagem por spray-dryer reúne as melhores condições de rendimento técnico em comparação com outros processos. Obtiveram rendimentos de processo acima de 20% e a instantaneização completa do produto. Abstract in english Cupuassu chocolate drink powder is a mixture of cupuassu powder, sugar, flavour and other ingredients of formulation. The product was processed by spray-dryer, leading a dry, pulverized and instantised product. The chocolate drink powder with water (concentrated) pass through spray-dryer forming small diameter globules that are arrested by a hot air stream. The rapid evaporation allows keeping low temperature at drying air, and no affecting the product. The process is a s (more) et of better conditions of technique and economical efficiency in comparison to other process. Cupuassu powder does not disperse readily in water owing to its oil content. Consequently, a form of cocoa with the oil removed is needed to produce an acceptably instant drink. The results obtained were satisfactory, due to the complete instantisation of the product after processing.

312

Effect of aronia berry honey syrup used for sweetening jams on their quality.  

The effects of sweetening agents on the quality of low sweetened jams were compared with respect to blackcurrant, raspberry, sour cherry, strawberry, and bilberry jams. The sweetening agents were sucrose, aronia berry honey syrup, and sucrose + honey syrup at a ratio of 1:1. The level of physicochemical indices, especially the content of vitamin C and anthocyanins determined directly after production and after 3- and 6-month storage, was used as the quality criterion for the evaluation of jams. Moreover, after 6-month storage the products were subjected to sensorial analysis. According to the accepted method of the investigation the produced jams were characterized by a 32-33% content of extract. During the production and 6-month storage the content of acids slightly and that of pectin considerably (from 26 to 46%) decreased, although the consistency of the jams was not affected thereby. In the case of vitamin C, its pronounced losses concerned raspberry (62-67% of the initial value), strawberry (57-61%), and sour cherry (57-58%), being distinctly smaller in blackcurrant (13-16%) and bilberry (15-35%) jams. With respect to anthocyanins a similar regularity was observed, the losses reaching 49-63% in strawberry jam, 40-56% in raspberry, 33-39% in sour cherry, 30-36% in blackcurrant, and 28-36% in bilberries. In almost all the products the losses of vitamin C and anthocyanins were higher when sweetening agent was aronia berry honey syrup. The organoleptic evaluation showed that the addition of aronia berry honey syrup to raspberry and strawberry jams slightly spoiled their colour but improved the aroma and taste. In the final score the significant differentiation in favour of the addition of aronia berry honey syrup concerned only blackcurrant, sour cherry, and bilberry jams. PMID:11534468

313

Differentiation of sheep milk and cheese based on quality and composition/ Diferenciación de la leche y queso de oveja en base a calidad y composición  

Abstract in spanish La rentabilidad de la producción ovina tradicional entre productores pequeños y medianos es muy baja, razón por la cual es deseable buscar alternativas con mayor valor agregado y diferenciación. Una alternativa de interés es la producción de leche ovina para la elaboración de quesos. El artículo analiza y discute las alternativas para modificar la composición de la leche y quesos de forma de diferenciarlos. Se discute como es posible cuantificar objetivamente dic (more) hos cambios y se mencionan brevemente algunas de las técnicas analíticas disponibles con ese fin. En general, los esfuerzos que se están realizando a nivel mundial se focalizan en la modificación del contenido y perfil de los ácidos grasos, así como la identificación y cuantificación de compuestos volátiles, terpenos, polifenoles y otros que permitirían diferenciar quesos y leche por sabor y olor, y que permiten asegurar la trazabilidad. Abstract in english Traditional sheep production for meat and wool for meat and wool among small and medium-sized Chilean farmers has low profitability. Therefore, there is interest in producing value-added, differentiated products. One alternative is the production of sheep milk and cheese. This arricie analyzes and discusses existing alternatives for modifying milk and cheese compositions with the aim of differentiating these products. Also, analytical techniques that allowthe chemical cha (more) racterization of milk and cheese are briefly mentioned. The main international thrusts are focused on the modification of the content and composition of milk fatty acids and on the identification of volatile compounds, terpenes, polyphenols and other analytes that allow differentiation of cheese types on the basis of aroma, taste and flavor and that would help in ensuring traceability.

314

Genetic analysis of the metabolic pathways responsible for aroma metabolite production by Saccharomyces cerevisiae.  

During alcoholic fermentation, higher alcohols, esters, and acids are formed from amino acids via the Ehrlich pathway by yeast, but many of the genes encoding the enzymes have not yet been identified. When the BAT1/2 genes, encoding transaminases that deaminate amino acids in the first step of the Ehrlich pathway are deleted, higher metabolite formation is significantly decreased. Screening yeast strains with deletions of genes encoding decarboxylases, dehydrogenases, and reductases revealed nine genes whose absence had the most significant impact on higher alcohol production. The seven most promising genes (AAD6, BAT2, HOM2, PAD1, PRO2, SPE1, and THI3) were further investigated by constructing double- and triple-deletion mutants. All double-deletion strains showed a greater decrease in isobutanol, isoamyl alcohol, isobutyric, and isovaleric acid production than the corresponding single deletion strains with the double-deletion strains in combination with ?bat2 and the ?hom2-?aad6 strain revealing the greatest impact. BAT2 is the dominant gene in these deletion strains and this suggests the initial transaminase step of the Ehrlich pathway is rate-limiting. The triple-deletion strains in combination with BAT2 (?bat2-?thi3-?aad6 and ?bat2-?thi3-?hom2) had the greatest impact on the end metabolite production with the exception of isoamyl alcohol and isovaleric acid. The strain deleted for two dehydrogenases and a reductase (?hom2-?pro2-?aad6) had a greater effect on the levels of these two compounds. This study contributes to the elucidation of the Ehrlich pathway and its significance for aroma production by fermenting yeast cells. PMID:23111598

315

Evaluation of Characteristic Aroma Compounds of Citrus natsudaidai Hayata (Natsudaidai) Cold-Pressed Peel Oil  

The characteristic aroma compounds of Citrus natsudaidai Hayata essential oil were evaluated by a combination of instrumental and sensory methods. Sixty compounds were identified and quantified, accounting for 94.08% of the total peel oil constituents. Limonene was the most abundant compound (80.68%), followed by ?-terpinene (5.30%), myrcene (2.25%) and ?-pinene (1.30%). Nineteen compounds which could not be identified in the original oil were identified in the oxygenated fraction. Myrcene, linalool, ?-pinene, ?-pinene, limonene, nonanal, ?-terpinene, germacrene D, and perillyl alcohol were the active aroma components (FD-factor > 36), whereas ?-copaene, cis-sabinene hydrate and 1-octanol were suggested as characteristic aroma compounds, having a Natsudaidai-like aroma in the GC effluent. Three other compounds, heptyl acetate, (E)-limonene oxide and 2,3-butanediol, which each showed a high RFA value (>35) were considered to be important in the reconstruction of the original Natsudaidai oil from pure odor chemicals. The results indicate that 1-octanol was the aroma impact compound of C. natsudaidai Hayata peel oil.   

316

A PCR-based marker for a locus conferring the aroma in Myanmar rice (Oryza sativa L.).  

Aromatic rice is an important commodity for international trade, which has encouraged the interest of rice breeders to identify the genetic control of rice aroma. The recessive Os2AP gene, which is located on chromosome 8, has been reported to be associated with rice aroma. The 8-bp deletion in exon 7 is an aromatic allele that is present in most aromatic accessions, including the most popular aromatic rice varieties, Jasmine and Basmati. However, other mutations associated with aroma have been detected, but the other mutations are less frequent. In this study, we report an aromatic allele, a 3-bp insertion in exon 13 of Os2AP, as a major allele found in aromatic rice varieties from Myanmar. The insertion is in frame and causes an additional tyrosine (Y) in the amino acid sequence. However, the mutation does not affect the expression of the Os2AP gene. A functional marker for detecting this allele was developed and tested in an aroma-segregating F(2) population. The aroma phenotypes and genotypes showed perfect co-segregation of this population. The marker was also used for screening a collection of aromatic rice varieties collected from different geographical sites of Myanmar. Twice as many aromatic Myanmar rice varieties containing the 3-bp insertion allele were found as the varieties containing the 8-bp deletion allele, which suggested that the 3-bp insertion allele originated in regions of Myanmar. PMID:22576235

317

[Characterization of aroma active compounds in blood orange juice by solid phase microextraction and gas chromatography-mass spectrometry-olfactometry].  

Volatile compounds of fresh blood orange juice were analyzed by solid phase microextraction and gas chromatography-mass spectrometry (SPME-GC-MS) and the aroma active compounds were identified by olfactometry. The volatile compounds were extracted by headspace solid phase microextraction (HS-SPME) using a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber for 40 min at 40 degrees C. The analysis was carried out using an HP 6890N GC equipped with an HP-5 column (30 m x 0.25 mm x 0.25 microm ) directly connected to an HP 5975 series mass selective detector and a sniffing port (ODP2, Gerstel) using helium as carrier gas. Compound identifications were made by the comparison of the mass spectra, retention times, retention indices (I(R)) and odor of the volatile components in the extracts with those of the corresponding reference standards. Forty-six compounds were identified by GC-MS and I(R). The major components of the juice were limonene (86.36%), linalool (3.69%), beta-myrcene (1.79%), octanal (1.32%) and valencene (1.27%). GC-MS-olfactometry analysis was performed to determine 34 compounds with aroma activity, of which 23 compounds were identified. The major contributors to orange juice aroma activity are ethyl butanoate, octanal, gamma-terpinene, 4-acetyl-1-methyleyclohexene, decanal, (-)-carvone, geranyl acetate, valencene. These compounds of strong aroma intensity represent 7.22% of the total volatile compounds. Other four unknown compounds (I(R), <800; I(R) = 1020, 1143, 1169, separately) are also the major contributors to the overall aroma. PMID:18959252

318

Initial Volatile Aroma Profiles of Young and Aged Awamori Shochu Determined by GC/MS/Pulsed FPD  

The natural vaporized aroma compounds present in awamori shochu were determined by a three-stage volatile organic compound (VOC) concentration technique consisting of on-line GC combined with MSD and PFPD. Several short-chain esters appear to predominantly contribute to the fruity aroma, including ethyl formate, methyl formate, ethyl propionate, and ethyl butyrate, which are typically contained in the natural vaporized aroma of awamori. Compounds that act as stimulant flavor compounds, including 2-methyl propanal, 3-methyl butanal, pentanal, hexanal, octanal, nonanal, and the ketones 2-butanone, 4-methyl-2-pentanone, 2-heptanone, and 3-octanone, were also detected as minor components. Sulfur compounds that impart strong odor/flavor, such as dimethyl trisulfide, benzothiazole, dimethyl trisulfide, and benzothiazole, were detected initially, but their levels tended to decrease with aging. We also found that ethers, including tetrahydrofuran and 1,1-diethoxyethane, increased in aged awamori. Thus the profiles of these compounds changed during aging, resulting in a milder and sweeter flavor. These results suggest that the natural vaporized aroma would contribute to the initial characteristics of the unique awamori aroma.   

319

Formulação de "chocolate" de cupuaçu e reologia do produto líquido/ Formulation of cupuassu "chocololate" and rheology of liquid product  

Abstract in portuguese O "chocolate" de cupuaçu é um produto cujo processo de fabricação consiste na transformação das amêndoas de cupuaçu (sementes após o beneficiamento) em um derivado com sabor, textura, odor e aparência semelhantes ao do chocolate elaborado com cacau. Este produto pode ser processado nas formas de pó e tabletes (meio amargo, ao leite e branco). O cupuaçu é um fruto cilíndrico, sendo que no seu interior possui sementes recobertas inteiramente por uma massa bran (more) ca e bastante espessa. O presente trabalho apresenta formulações de "chocolates" de cupuaçu (meio amargo, ao leite e branco), em que a fase gordurosa se compõe de mistura de gordura de cupuaçu e manteiga de cacau, juntamente com parâmetros reológicos do produto líquido. Utilizaram-se os sensores vane e cilindro concêntrico para a determinação reológica. Os produtos obtidos apresentaram similaridades com chocolates tradicionais em aroma e nos parâmetros reológicos a 40 ºC, com maior maciez. Abstract in english Cupuassu "chocolate" is a product whose process of manufacture consists to transform cupuassu seeds (after fermentation, toasting and grinding) in derived one with flavour, texture, odor and appearance similar to chocolate elaborated with cocoa. It could be processed as powder and tablets (semi sweet, milk and white types). Cupuassu is a cylindrical fruit, and in its interior there are seeds involved by a white and thick mass. This work intends to show formulations of cup (more) uassu chocolates (semi sweet, milk and white types), where the fatty phase is blends of cupuassu fat and cocoa butter (1 to 5.9 %), and the flow behaviour of the product was evaluated using the vane and coaxial cylinder sensors at 40 ºC. The products obtained were very similar to the tablets of traditional chocolates in flavour and rheological parameters at 40 ºC, with flow properties of soft chocolate.

320

Polymer characterization and optimization of conditions for the enhanced bioproduction of benzaldehyde by Pichia pastoris in a Two-Phase Partitioning Bioreactor.  

Benzaldehyde, with its apricot and almond-like aroma, is the second most abundantly used molecule in the flavour industry, and is most commonly produced via chemical routes, such as by the oxidation of toluene. Biologically produced benzaldehyde, whether by extraction of plant material or via microbial biotransformation, commands a substantial price advantage, and greater consumer acceptance. Methylotrophic yeast, such as Pichia pastoris, contain the enzyme alcohol oxidase (AOX), which, in the presence of alcohols other than methanol, are able to yield aldehydes as dead-end products, for example, benzaldehyde from benzyl alcohol. In this work, we have determined that benzaldehyde, and not benzyl alcohol, is inhibitory to the transformation reaction by P. pastoris, prompting the development of a selection strategy for identifying sequestering polymers for use in a Partitioning Bioreactor that was based on the ratio of partition coefficients (PCs) for the 2 target molecules. Additionally, we have now confirmed for the first time, that the mechanism of solute uptake by amorphous polymers is via absorption, not adsorption. Finally, we have adopted a common strategy used for the production of heterologous proteins by P. pastoris, namely the use of a mixed methanol/glycerol feed for inducing the required AOX enzyme, while reducing the time required for high density biomass generation. All of these components were combined in a final experiment in which 10 % of the polymer Kraton D1102K, whose PC ratio of benzaldehyde to benzyl alcohol was 14.9, was used to detoxify the biotransformation in a 5 L Partitioning Bioreactor, resulting in a 3.4 fold increase in benzaldehyde produced (14.4 g vs. 4.2 g) relative to single phase operation, at more than double the volumetric productivity (97 mg L(-1) h(-1) vs. 41 mg L(-1) h(-1) ). Biotechnol. Bioeng. © 2012 Wiley Periodicals, Inc. PMID:23124524

 
 
 
 
321

Furan in coffee: pilot studies on formation during roasting and losses during production steps and consumer handling.  

The occurrence of furan in some food products has already been known for a few decades, and it has been reconfirmed in more recent investigations that furan is present in a variety of foodstuffs. This list of products includes roasted coffee, which has been shown to generate furan as a result of the heat treatment at roasting which is applied to achieve the desired aroma and flavour profile of a roasted coffee. The objective of this study is to provide data to allow a better understanding of the available data of furan in coffee, the kinetics of furan generated during roasting, and to estimate the reduction of furan levels afterwards due to subsequent processing steps and consumer handling. Finally, the study is meant as a contribution to establish exposure data on the basis of scientific data at the stage of coffee consumption. This paper shows that the formation of furan during roasting is dependent on roasting conditions and is, therefore, directly linked to achieving targeted flavour profiles. Furthermore, it is demonstrated that modifications in process conditions potentially to reduce furan levels may have the opposite effect on other undesired reaction products of the roasting chemistry such as, for example, acrylamide. Due to the high volatility of furan, any subsequent processing step or consumer handling has an impact on the level of furan. As a guidance from this study and in consideration of the identified losses of each process and handling step on the basis of the trial conditions, it is estimated that only approximately 10% of the initially generated furan during roasting gets into the cup of coffee for consumption. PMID:20155535

322

Aroma-impact compounds in Lysimachia foenum-graecum extracts  

Two different extraction methods were used to obtain representative extracts from stems and leaves of Lysimachia foenum-graecum, a Chinese plant with a smoky, spicy, green, woody and caramel aroma. An extract was obtained by steam distillation followed by pentane back-extraction. Plants were also extracted with dichloromethane, and the non-volatile compounds were separated from volatiles by high-vacuum distillation (SAFE). Compared to the steam distillate extract, the SAFE-distilled extract was judged to be more similar to the aroma of the starting materials. The aroma-impact compounds of the SAFE extract were then determined using multidimensional GC. From the detection frequencies and the intensities of the peaks, 47 peaks with odour-activity were determined, using an adaptation of the G...

323

VARIETAL AROMA COMPOUNDS OF VITIS VINIFERA CV. KHAMRI GROWN IN TUNISIA  

ABSTRACT The aroma composition of the grape juice of Khamri, a native variety of Vitis vinifera grown in Tunisia, was investigated for the first time. A total of 27 free and 20 glycosidically bound compounds were identified by gas chromatography-mass spectrometry. According to the obtained results, the aroma compounds were C6 alcohols, benzene compounds, terpenes, acids and norisoprenoids. On the basis of gas chromatography-olfactometry, these compounds were grouped, according to volatiles exhibiting the identical odor quality, into 10 groups of the same character (aromatic series) as a way of establishing an aroma profile for the studied variety. The high glycosidically bound norisoprenoid concentrations and the absence of the bound form of the acids were a positive factor for the Khamri ...

324

Characteristic Odor Components of Citrus reticulata Blanco (Ponkan) Cold-pressed Oil  

Citrus reticulata Blanco (ponkan) cold-pressed oil and its oxygenated fraction were studied by analytical (GC and GC/MS) and sensory analyses. The monoterpene group was predominant, accounting for more than 89.6% (w/w), of which limonene was the most abundant (80.3%). Among the oxygenated compounds, octanal and decanal were the major ones among 12 aldehydes accounting for >1.5%; six alcohols were identified with a total concentration of >0.7%, while oxides, ketones and esters did not quantitatively or qualitatively contribute to the oil. Sniffing the ponkan cold-pressed oil and its oxygenated fraction demonstrated that octanal and decanal were the characteristic odor components of ponkan. Reconstruction of the ponkan aroma model and its sensory evaluation by a hedonic test were performed, showing that, in addition to octanal and decanal which played important roles, (R)-(+)-limonene contributed to the aroma model as a background component, making the aroma model very similar to that of the original.   

325

Aroma therapy and medfly SIT  

A summary of the main findings of the research program on the biological competence of mass-reared, sterile males of the Mediterranean fruit fly (med fly), Ceratitis capitata (Wied.) and the development and implementation of the sterile insect technique (SIT) against this pest is presented. The potential application of aroma therapy to improve the mating success of sterile med fly males is studied. The report assumes a loosely chronological framework as it documents progression along two experimental scales: the number of males simultaneously exposed to ginger root oil, starting with small groups of 25 males and ending with rooms with nearly 200 million males; the experimental arena used to test the effects of aroma therapy, progressing from standard field-cages to large field enclosures to the open field. In addition, brief comments are offered regarding the potential negative effects of GRO exposure, the mechanisms underlying GRO-mediated improvement in male mating success, and the financial costs of GRO aroma therapy. (MAC)

326

Chemical and sensory effects of the freezing process on the aroma profile of black truffles (Tuber melanosporum)  

The aim of this work was to evaluate the effect of freezing black truffles (Tuber melanosporum) on their aroma both in sensory and chemical terms. The truffles were frozen at temperatures of -20 to -80degreeC. Descriptive and discriminative sensory and chemical analyses, based on headspace solid phase microextraction followed by gas chromatography-mass spectrometry analysis (HS-SPME-GC-MS), were carried out after 1, 20, 40 and 60days. Fifteen compounds with high aromatic potential in truffles were determined. Their selective ion peak areas were calculated, summed and expressed as percentage of active odour compound, in order to monitor changes in odour profile. The aroma of frozen truffles differed significantly from the aroma of fresh truffles. Volatile composition data revealed that T. m...

327

SPME-GC-MS detection of volatile compounds in apricot varieties  

Aroma compounds of the eight Malatya apricot cultivars, six cultivars grown in the same breeding conditions from different locations and one hybrid cultivar were determined using SPME-GC-MS technique. In general, total concentration (sum of identified and unidentified peaks) of aroma compounds in Malatya apricot cultivars were lower than those others. Total concentration of aroma compounds were found to be in the range of 514 and 6232mg/kg fresh weight. The main volatiles of apricot cultivars were aldehydes, alcohols, acetates, esters, terpenes and acids. Among these compounds; ethanol, hexanal, hexyl acetate, (Z)-3-hexenyl acetate, (E)-2-hexenyl acetate, 1-hexanol, (Z)-3-hexenol and (E)-2-hexen-1-ol, were present in all cultivars studied at certain levels.

328

A PCR-based marker for a locus conferring the aroma in Myanmar rice (Oryza sativa L.)  

Aromatic rice is an important commodity for international trade, which has encouraged the interest of rice breeders to identify the genetic control of rice aroma. The recessive Os2AP gene, which is located on chromosome 8, has been reported to be associated with rice aroma. The 8-bp deletion in exon 7 is an aromatic allele that is present in most aromatic accessions, including the most popular aromatic rice varieties, Jasmine and Basmati. However, other mutations associated with aroma have been detected, but the other mutations are less frequent. In this study, we report an aromatic allele, a 3-bp insertion in exon 13 of Os2AP, as a major allele found in aromatic rice varieties from Myanmar. The insertion is in frame and causes an additional tyrosine (Y) in the amino acid sequence. However...

329

Comparative Effect of the Addition of -, -, or -Cyclodextrin on Main Sensory and Physico-Chemical Parameters  

Abstract:- Although -, -, and -cyclodextrins (CDs) have been widely used to improve the color of different fruit juices, a comparative study of the effect of these natural CDs on other properties that also influence pear juice quality, such as odor and aroma, have not been reported yet. In this study, the comparative effect of the addition of -, -, and -cyclodextrin, the only CDs authorized to be used in the food industry by U.S. Food and Drug Administration (FDA) and European Union, on the pear juice quality was evaluated for the first time. Several instrumental and sensory properties of this fruit juice, such as color, volatile composition, odor, and aroma have been evaluated in the absence and presence of -, -, and -CD. A study of the aroma profile of pear juice showed that esters, alde...

330

Fast Quantitative Determination of Aroma Volatile Constituents in Melon Fruits by Headspaceâ??Solid-Phase Microextraction and Gas Chromatographyâ??Mass Spectrometry  

Since the aroma is one of the essential factors for evaluating fruit quality, a headspaceâ??solid-phase microextraction and gas chromatographyâ??mass spectrometry method for the identification and quantification of the aroma volatile constituents in melon fruits has been developed. Two different varieties of Cucumis melo L., reticulatus and inodorus, have been analyzed and 66 volatile compounds have been identified and quantified; among these, the impact aroma compounds are included too. The volatile compounds have been identified by linear retention index, mass spectra, standard injection, and reference data; the quantification has been carried out by the standard addition technique. The method proposed showed good linearity within the concentration range tested; the precision, CV was <15...

331

Influence of atmospheric oxygen and ozone on ripening indices of normal (Rin) and ripening inhibited (rin) tomato cultivars  

Ethylene (10 ppm) dependent mediation of normal and mutant (rin) tomato fruit ripening was promoted by 100% oxygen, 3.7 pphm ozone, or their combination. All ripening indices studied (respiration, chlorophyll degradation, carotenoid accumulation, softening, and aroma development) were promoted by oxygen and/or ozone. Ozone also acted independent of ethylene in promoting chlorophyll degradation and aroma development in normal fruit, but did not appreciably affect these quality attributes in mutant fruit. Lycopene accumulation in normal and mutant fruit and aroma formation in normal fruit were promoted to a greater extent by ozone than were other ripening indices. Mutant (rin) fruit contained 27% of the lycopene that was present in normal (Rin) fruit after ripening in O/sub 2/ containing 10ppm ethylene and 3.7 pphm ozone, whereas they contained only 3% of the lycopene in normal fruit after ripening in air containing 10ppm ethylene.

332

Impact of cover crops in vineyard on the aroma compounds of Vitis vinifera L. cv Cabernet Sauvignon wine  

This study compared the influence of different cover crops with clean tillage on wine aroma compounds of 5-year-old Cabernet Sauvignon vines. White clover, alfalfa, and tall fescue were used in the vineyard and compared with clean tillage. Aroma compounds of wine were analysed by solid-phase microextraction gas chromatography-mass spectrometry (SPME-GC/MS). Forty-seven volatile compounds were identified and quantified. Wines made from grapes grown with various cover crops had higher levels of aroma compounds. Ethyl acetate, isoamyl acetate, ethyl octanoate, ethyl hexanoate, phenylethyl acetate, isoamyl alcohol, linalool, citronellol, b-damascenone, a-ionone, and 5-amyl-dihydro-2(3H)-furan were the impact odorants of sample wines. Wines from cover crop also had higher contents of these impa...

333

Aroma WaterLOGSY: a fast and sensitive screening tool for drug discovery.  

One-dimensional NMR spectroscopy has proven to be a powerful technique for screening compound libraries in drug discovery. We report a novel water ligand-observed gradient spectroscopy (WaterLOGSY) pulse sequence, named Aroma WaterLOGSY, that selectively detects aromatic WaterLOGSY signals from compounds or ligands. In the Aroma WaterLOGSY, water magnetization is untouched after water excitation and utilizes the whole period of the remaining pulse sequence to relax back to the +z direction. Due to the phase cycling design, the water magnetization is allowed to relax for the period of two full scans before it gets inverted again. Therefore, the recycle delay can be significantly shortened. Within similar experimental time, Aroma WaterLOGSY shows approximately two times higher sensitivity than the standard scheme. This method also allows the use of non-deuterated reagents, thereby accelerating experimental set-up time for ligand-binding studies. PMID:21038321

334

Aroma WaterLOGSY: a fast and sensitive screening tool for drug discovery  

Abstract One dimensional NMR spectroscopy has proven to be a powerful technique for screening compound libraries in drug discovery. We report a novel water ligand observed gradient spectroscopy (WaterLOGSY) pulse sequence, named Aroma WaterLOGSY, that selectively detects aromatic WaterLOGSY signals from compounds or ligands. In the Aroma WaterLOGSY, water magnetization is untouched after water excitation and utilizes the whole period of the remaining pulse sequence to relax back to the + z direction. Due to the phase cycling design, the water magnetization is allowed to relax for the period of two full scans before it gets inverted again. Therefore, the recycle delay can be significantly shortened. Within similar experimental time, Aroma WaterLOGSY shows approximately two times higher sens...

335

Influence of temperature on membrane permeability during pervaporative aroma recovery  

The influence of operating temperature on membrane permeability was studied and compared with the effect of temperature on the driving force for permeation. A hydrophobic polyoctylmethyl siloxane membrane was used. For the feed mixture, an aqueous solution of aroma compounds containing four alcohols, one aldehyde, and five esters was used. Temperature had a strong effect on mass transfer and selectivity, both of which increased with increasing temperature. However, the selectivity for a component with a high activation energy for permeation increased more with temperature than did a component with a low activation energy for permeation. This caused a variation in the aroma composition of the permeate. The study showed that it is possible to estimate the activation energy for permeation of aroma compounds, and thus the influence of temperature on the internal mass transfer, through their hydrophobicity, size, and a complementary comparison of the activation energies for permeation for some other permeants of the same chemical group.

336

Understanding Darjeeling tea flavour on a molecular basis  

Darjeeling teas are the highest grown teas in the world and preferred for its flavour, aroma and quality. Apart from the genetic makeup of the plant, earlier reports suggest that insect infestation, particularly jassids and thrips triggers the aroma and flavour formation in Darjeeling tea. The present work encompasses the identification of the genes/transcriptomes responsible for the typical flavour of Darjeeling tea, besides understanding the role of jassids and thrips in particular, in producing the best cup character and quality. The quantitative real time PCR analysis was based on a suppression subtractive hybridisation forward library of B157 (tea clone infested with thrips), providing us transcripts related to aroma and flavour formation. We observed the expression of genes like leuc...

337

Analysis of free and glycosidically bound compounds of ash gourd (Benincasa hispida): Identification of key odorants  

Free and glycosidically bound aroma compounds of ash gourd were investigated. Gas chromatography-mass spectrometry (GC/MS) analysis of the free aroma compounds isolated by both steam distillation and high vacuum distillation revealed the presence of acetoin as the major constituent in both the oils. Acetoin was also identified as the major constituent existing as glycosidic conjugate. GC-olfactometry (GC-O) of the volatile oil based on detection frequency (olfactometry global analysis) was further used to characterise odour active compounds of the vegetable. Based on odour activity value (OAV) measurements the potent odorant among these were identified as acetoin (9522.5), octanal (8571) and nonanal (24,000). The region corresponding to the characteristic ash gourd aroma when collected by ...

338

Effect of Sweet Orange Aroma on Experimental Anxiety in Humans  

Abstract Objectives: The objective of this study was to evaluate the potential anxiolytic effect of sweet orange (Citrus sinensis) aroma in healthy volunteers submitted to an anxiogenic situation. Design: Forty (40) male volunteers were allocated to five different groups for the inhalation of sweet orange essential oil (test aroma: 2.5, 5, or 10 drops), tea tree essential oil (control aroma: 2.5 drops), or water (nonaromatic control: 2.5 drops). Immediately after inhalation, each volunteer was submitted to a model of anxiety, the video-monitored version of the Stroop Color-Word Test (SCWT). Outcome measures: Psychologic parameters (state-anxiety, subjective tension, tranquilization, and sedation) and physiologic parameters (heart rate and gastrocnemius electromyogram) were evaluated before...

339

Reduced fat and sugar vanilla ice creams: Sensory profiling and external preference mapping  

The aims of this study were (1) to map sensory attributes of vanilla ice cream with reduced fat and sugar, and (2) to determine drivers of liking by applying external preference mapping and reveal the relationship between descriptive attributes and hedonic judgments using the partial least squares method. Descriptive sensory profiles (n=11) and consumer test (n=117) of 6 samples of vanilla ice cream (3 traditional and 3 with reduced fat and sugar) were determined. The attributes brightness and sweet aftertaste for sample and creaminess (appearance and texture) and sweet aroma contributed positively to the acceptance of ice cream samples. The attributes aeration, powdered milk aroma and flavor, and white chocolate aroma and flavor contributed positively to the acceptance of the ice creams. ...

340

Release of wine monoterpenes from natural precursors by glycosidases from Oenococcus oeni  

It is now well established that wine-related lactic acid bacteria (LAB), especially Oenococcus oeni, possess glycosidase activities that positively contribute to wine aroma through the hydrolysis of grape-derived aroma precursors. In our recent studies, we have identified and characterised several LAB glycosidases with potential in these terms. Here, we report that both a glucosidase and an arabinosidase from O. oeni can release high amounts of monoterpenes from natural substrates under optimal conditions, indicating that these intracellular enzymes might play a significant role in the hydrolysis of aroma precursors during malolactic fermentation. The enzymes from O. oeni exhibited broad substrate specificities (release of both primary/tertiary terpene alcohols) and were even active in gra...

 
 
 
 
341

A comprehensive review on Sauvignon blanc aroma with a focus on certain positive volatile thiols  

Vitis vinifera L. cv. Sauvignon blanc wines have become increasingly popular as it is a cultivar that can be influenced in the vineyard and the cellar to produce a range of wine styles. Although originally from France, Sauvignon blanc is now widely cultivated in the wine growing regions of the world. These wines are usually given aroma descriptors such as green pepper, grassy, asparagus; while other more tropical aromas include passion fruit and guava. Volatile thiols, specifically 4-mercapto-4-methylpentan-2-one, 3-mercaptohexan-1-ol and 3-mercaptohexyl acetate, are a group of chemical compounds contributing to a large extent to the perception of the tropical aroma. A recent influx of new research has given insight into the precursors, development and reactions of volatile thiols in Sauvi...

342

Use of sense masking to study sensory modalities singly: Interest for the understanding of apple in-mouth perception  

The relative contribution of aroma, taste and texture modalities to overall perception, as well as the interactions which can occur between them, were studied during the consumption of natural foods, i.e. apples. Aroma, taste and texture perceptions were masked in that order by employing different masking agents, separately or combined, allowing one or several of these senses to be omitted during various matching tasks. By means of Common Components and Specific Weight Analysis (CCSWA), matching results were compared to those of rating tests performed by a trained panel, without masking agents. Taste was the modality which contributed most to apple discrimination, followed by texture and aroma. While taste did not seem to interact with texture, its perception may have been amplified by odo...

343

Characterization of Aroma Compounds in Chinese Bayberry (Myrica rubra Sieb. et Zucc.) by Gas Chromatography Mass Spectrometry (GC-MS) and Olfactometry (GC-O).  

The aroma-active compounds in Chinese bayberry were identified using gas chromatography-olfactometry (GC-O) and GC-mass spectrometry techniques. The volatile compounds were extracted using Liquid-liquid extraction, solvent-assisted flavor evaporation and headspace solid-phase microextraction (HS-SPME), respectively. On the basis of odor intensity, the most important aroma compounds in Chinese bayberry samples were caryophyllene, menthol, 4-terpineol, linalool oxide, linalool, benzyl alcohol, ?-methylbenzyl alcohol, ?-phenylethanol, 3-methylbutanoic acid and acetic acid, and so on. Moreover, HS-SPME technique was employed to investigate the aroma compounds among immature and mature waxberry fruits. The results showed that terpenes (for example, ?-caryophyllene) was predominant and its concentration represented over 89.9% of the overall compounds, and alcohols, aldehydes, ketones, esters, acids, and others were typically present in lesser amounts. Finally, principal component analysis revealed that there was also significant difference between immature and mature waxberry fruits. PMID:23009608

344

Fruit quality and volatile fraction of `Pink Lady' apple trees in response to rootstock vigor and partial rootzone drying  

BACKGROUND: Partial rootzone drying (PRD) is a novel deficit irrigation technique consisting in the alternated wetting of only one side of the rootzone, which induces partial stomatal closure and increased water use efficiency. The effect of PRD and rootstock vigor on `Pink Lady' apple fruit quality and aroma profile was studied using solid-phase micro-extraction in headspace and gas chromatography/mass spectrometry.RESULTS: PRD irrigation generally did not affect quality attributes, whereas it influenced the aroma of the apple fruit. In particular, PRD improved the aroma of the fruit flesh, while it decreased the volatile fraction in the peel, where most of the compounds are concentrated. Taking into account the relative contribution of the flesh and peel (w/w) to the apple fruit, the vol...

345

Simulation of retronasal aroma of white and red wine in a model mouth system. Investigating the influence of saliva on volatile compound concentrations  

The influence of saliva on aroma release from white and red wines was studied in a model mouth system. Aroma compounds were analysed in the dynamic headspace of wines by solid phase micro extraction/gas chromatography with flame ionization detection. Volatile compounds were identified by solid phase micro extraction/gas chromatography-mass spectrometry, resulting in a total of 43 compounds in white wine and 41 in red wine. The results showed a greater influence of saliva on aroma release in white wine than red wine. In white wine treated with human saliva, esters and fusel alcohols, responsible for fruity and fusel oil odours, were reduced of 32-80%; by contrast, the concentration of 2-phenylethanol and furfural, responsible for rose and toasted almond notes, increased by 27% and by 155%, ...

346

Use of an artificial mouth to study bread aroma  

This work aimed to select artificial mouth extraction conditions to obtain an aroma extract of bread close to that perceived in the human mouth in terms of similarity and intensity. Once the representative extraction conditions were determined, they were used to show the influence of mastication and the effect of saliva on bread aroma release. The significance of mastication was shown by comparing headspace aromatic extracts with artificial mouth extracts. The results showed that headspace extraction, associated with a previous crushing of bread, did not provide an extract similar to that obtained after mastication. The determination of the influence of saliva on bread aroma was done respecting the ratio between saliva and bread in the human oral cavity. The results revealed that bread was...

347

The metabolic responses to aerial diffusion of essential oils.  

Anxiety disorders are the most prevalent psychiatric disorders and affect a great number of people worldwide. Essential oils, take effects through inhalation or topical application, are believed to enhance physical, emotional, and spiritual well-being. Although clinical studies suggest that the use of essential oils may have therapeutic potential, evidence for the efficacy of essential oils in treating medical conditions remains poor, with a particular lack of studies employing rigorous analytical methods that capture its identifiable impact on human biology. Here, we report a comprehensive gas chromatography time-of-flight mass spectrometry (GC-TOFMS) based metabonomics study that reveals the aromas-induced metabolic changes and the anxiolytic effect of aromas in elevated plus maze (EPM) induced anxiety model rats. The significant alteration of metabolites in the EPM group was attenuated by aromas treatment, concurrent with the behavioral improvement with significantly increased open arms time and open arms entries. Brain tissue and urinary metabonomic analysis identified a number of altered metabolites in response to aromas intervention. These metabolic changes included the increased carbohydrates and lowered levels of neurotransmitters (tryptophan, serine, glycine, aspartate, tyrosine, cysteine, phenylalanine, hypotaurine, histidine, and asparagine), amino acids, and fatty acids in the brain. Elevated aspartate, carbohydrates (sucrose, maltose, fructose, and glucose), nucleosides and organic acids such as lactate and pyruvate were also observed in the urine. The EPM induced metabolic differences observed in urine or brain tissue was significantly reduced after 10 days of aroma inhalation, as noted with the loss of statistical significance on many of the metabolites in the aroma-EPM group. This study demonstrates, for the first time, that the metabonomics approach can capture the subtle metabolic changes resulting from exposure to essential oils and provide the basis for pinpointing affected pathways in anxiety-related behavior, which will lead to an improved mechanistic understanding of anxiolytic effect of essential oils. PMID:22984571

348

D-meson production by muons in the COMPASS experiment at CERN  

One of the physics goals of the COMPASS experiment at CERN was to measure the contribution of gluons to the nucleon spin. To achieve this, it was proposed to scatter polarized 160 GeV/c muons on a polarized deuteron target and to detect D mesons in the final state. The underlying process in this D meson production is supposed to be the Photon-Gluon Fusion (PGF), where a virtual photon emitted by the muon interacts with a gluon from the target nucleon, producing a charm-anticharm quark pair. Fragmentation of a charm (anticharm) quark leads with high probability to the creation of a D{sup 0} or D{sup *} meson, which COMPASS detects via the D{sup 0}{yields}K{pi} and D{sup *}{yields}D{sup 0}{pi}{yields}K{pi}{pi} decay modes. From the longitudinal cross section spin asymmetries of the D meson production and theoretical predictions for the PGF cross section, the gluon contribution to the nucleon spin has been measured by the COMPASS experiment. The results presented in the thesis are the following. Based on data from the year 2004 a total visible cross section of 1.8{+-}0.4 nb, for the D{sup *} meson production, has been measured, with the error being dominated by systematic effects. It is validated that the D mesons are indeed produced through the PGF process, by comparison of measured D meson kinematic distributions to the ones predicted by a theory (AROMA generator). A good agreement was found for the distribution shapes, which confirms that PGF plays a major role. However, a 20% difference was found in the number of produced D{sup 0} and D{sup 0} mesons (and for the D{sup *+} and D{sup *-} mesons as well) which is significantly larger than predicted by AROMA. Kinematic distributions of D{sup 0} and D{sup *} mesons were compared with the background and also with the nearby K{sup *}{sub 2}(1430){sup 0} resonance, using all longitudinal data taken in 2002-2006. The particle-antiparticle asymmetry has been studied as a function of several kinematic variables. The 20% excess of mesons decaying into K{sup +}{pi}{sup -} over mesons decaying into K{sup -}{pi}{sup +} was observed for all three mesons. The behavior of the D{sup 0}/D{sup 0} (and D{sup *+}/D{sup *-}) asymmetries as a function of virtual photon energy suggests that associated production of D{sup *-}{lambda}{sup +}{sub c} or D{sup 0}{lambda}{sup +}{sub c} may be responsible for the observed effect. The longitudinal double spin asymmetries have been studied for the D{sup 0}, D{sup *} and K{sup *}{sub 2}(1430){sup 0} mesons separately for particle, antiparticle and for the sum of particle and antiparticle. It was found that the asymmetries extracted for D{sup 0} and D{sup *} mesons are compatible with zero. A 3-sigma deviation from zero asymmetry was observed for the K{sup *}{sub 2}(1430){sup 0} meson. An investigation of the K{sup *}{sub 2}(1430){sup 0} double spin asymmetry reveals a dependence as function of the Bjorken x{sub Bj} variable. (orig.)

349

Relationships among sensory analysis, isoflavone and hexanal contents of soymilk powder  

Abstract in portuguese O trabalho foi conduzido com o objetivo de descrever os atributos sensoriais de bebidas de extratos de soja em pó produzidos a partir de cultivares desprovida de lipoxigenases, convencional e tipo hortaliça e dois extratos comerciais e correlacioná-los com as quantidades de isoflavonas e n-hexanal nos extratos em pó. Os extratos de soja em pó obtidos em laboratório foram caracterizados pelos atributos: aroma de feijão cozido e de algodão doce; sabor de grão cozid (more) o, de malte e gosto doce sugerindo, sabor suave. Os extratos comerciais apresentaram forte aroma de soja tostada, de ranço, de sementes de gergelim e de peixe; sabor de soja tostada, gosto amargo e de sementes de gergelim; gosto amargo (com nariz preso) e consistência de amido. Não foram observadas diferenças sensoriais entre os extratos produzidos em laboratório, indicando a ocorrência da inativação das enzimas lipoxigenases durante o processamento dos produtos. Contudo, diferenças marcantes entre os extratos obtidos em laboratório e os comerciais quanto aos atributos sensoriais estudados foram encontradas provavelmente, devido às técnicas desconhecidas de processamento utilizadas pelos fabricantes dos produtos comerciais. O teor médio de n-hexanal presente nos extratos de soja comerciais e produzidos em laboratório apresentou correlação positiva e significativa com o atributo aroma de grão cozido, já a quantidade de isoflavonas com aroma de grão cozido e de algodão doce, sabor de grão cozido, de malte, gosto doce e consistência de amido. Abstract in english The objective of this work was to study the sensory attributes and their relationships with isoflavones and hexanal contents of soymilks made in laboratory and commercial samples. The laboratory soymilk samples showed cooked grain and cotton candy aroma and cooked grain, malty and sweetness flavor (a mild flavor). The commercial samples presented stronger roasted soy, rancid, sesame seeds and fishy aroma and roasted soy, sesame seeds and bitterness flavor, and bitter tast (more) e (closed nose) and starchy texture. No differences were noted among laboratory soymilks, denoting inactivation of lipoxygenases enzymes in the soymilks process. There were differences between the samples prepared in laboratory and commercial soymilks, which was due to several factors related to processing techniques. The hexanal average content was positively associated with the cooked grain aroma and isoflavones was positively associated with the cooked grain and cotton candy aroma, cooked grain, malty and sweetness flavor and starchy texture.

350

Inclusão do farelo grosso de trigo na dieta e seu efeito sobre as propriedades físicas e sensoriais da carne caprina/ Inclusion of coarse wheat bran in the diet and its effect on physical and sensorial properties of goat meat  

Abstract in portuguese Avaliou-se o efeito de diferentes níveis de inclusão do Farelo Grosso de Trigo (FGT) (0,0; 8,9; 19,8 e 31,7%) na dieta sobre os atributos sensoriais (aroma caprino, aroma estranho, cor, textura, maciez, sabor caprino, suculência e aparência geral) e nas qualidades físico-químicas (pH e perdas de líquido no cozimento e cor da carne), operando no sistema CIE - L*, a* e b* de lombos caprinos em delineamento inteiramente casualizado (4 tratamentos e 4 repetições). A (more) inclusão do FGT não influenciou o aroma da carne, no entanto, houve efeito significativo para a cor da carne e sabor característico caprino. A textura, maciez e aparência geral foram decrescentes. O pH foi quadrático com ponto de máxima de 18,53% e o percentual médio de perdas no cozimento foi de 25,5%. Nos parâmetros de cor a luminosidade (L*) teve efeito linear decrescente variando de 30,2 a 32,2; a cor vermelha (a*) foi intensificada variando de 7,56 a 8,47 com aumento dos níveis, enquanto a cor amarela (b*) apresentou equação quadrática com ponto de máxima de 14,53%. A inclusão de níveis crescentes de FGT na dieta animal alterou todos os atributos da carne caprina, exceto o aroma. De acordo com a avaliação cromática, a coloração da carne caprina apresentou-se mais escura com níveis mais elevados de FGT. Abstract in english The effect of inclusion levels of Coarse Wheat Bran (CWB) (0; 8.9; 19.8 and 31.7%) in the animal diet on sensorial attributes (goat aroma, strange aroma, color, texture, tenderness, goat flavor, juiciness and general appearance) and physical-chemical characteristics (pH, losses during cooking and color of the meat operating in the CIE (L*, a* e b*) system of goat loins were evaluated. A statistical design of four treatments and four replications was used. The inclusion of (more) CWB did not significantly affect goat meat aroma. However, there was a quadratic effect on color and on the characteristic taste of the meat. Texture, tenderness and general appearance decreased linearly. For pH, the behavior was quadratic, with a maximum of 18.53% and the average percentage of losses during cooking was 25.5%. There was a decreasing linear effect on brightness (L*), which varied from 30.2 to 32.2; red color (a*) was intensified with the increase of CWB levels, and varied from 7.56 to 8.47, while yellow color (b*) showed a quadratic behavior (maximum of 14.53%). The increasing inclusion of CWB in the animal diet affected all sensorial attributes, except for aroma. According to the chromatic evaluation, goat meat color was darker with increasing CWB levels.

351

Identification of the Characteristic Volatile Flavor Compounds Formed by Cooking Squid (Todarodes pacificus STEENSTRUP)  

Volatile compounds were isolated from cooked squid (Todarodes pacificus STEENSTRUP) using a porous polymer resin with Tenax TA column chromatography. Aroma extract dilution analysis determined the following six compounds as the main potent odorants of cooked squid: 4,5-dimethylthiazole (green), 2-acetyl-2-thiazoline (nutty), 2,5-dimethylpyrazine (popcorn-like), methional (potato, soy sauce), furaneol (caramel-like) and an unidentified compound (floral). Among them, based on the high concentration and odor characteristics, it is concluded that furaneol was the most important compound contributing to the sweet aroma of cooked squid.   

352

Kiwifruit flavour: A review  

The commercially available kiwifruit species are appreciated for their flavour and distinctive appearance. The aromas of the commercial species Actinidia deliciosa 'Hayward', Actinidia chinensis 'Hort16A' and Actinidia arguta have been studied applying diverse analytical techniques. Major volatile compounds and important odorants have been identified. The effects of ripening and storage have been evaluated. The perception of kiwifruit flavour by consumers has been assessed, also considering the need to identify flavour targets for breeding. The present review in addition gives insights on the new research area concerning gene regulation of the aroma of kiwifruit.

353

Glass transition temperatures and some physical and sensory changes in stored spray-dried encapsulated flavors  

Commercial spray-dried powder flavors (strawberry and orange) encapsulated in different amorphous matrices (maltodextrin and maltodextrin-sucrose) were stored for 20 days under constant relative humidities of 32%, 43%, 58% and 75%. Glass transition temperatures (Tg) of the different powders and maltodextrin DE 12 were measured using differential scanning calorimetry (DSC). Caking/collapse visual observations and aroma strength (measured by a trained sensory panel) were recorded and correlated with the glass transition temperature of the different spary-dried flavors. Glass transition data explained collapse occurrence and loss of aroma strength in encapsulated strawberry and orange flavors after storage at various relative humidities.The presence of sucrose in the carrier formulation negat...

354

The Influence of Molecular Structure on Odor Qualities and Odor Detection Thresholds of Volatile Alkylated Phenols  

The relationship between chemical structure and odor characteristics of aroma compounds is interesting in terms of establishing a fundamental understanding and, in the long term, a perspective for the prediction of odor qualities and intensities of unknown compounds; on the other hand, such studies provide a useful tool to analytically elucidate compounds that are exceptionally potent odor contributors to a specific smell. In this respect, a broad knowledge of compounds with regard to their odor threshold and smell specificities compiled in a comprehensive odor library would drastically simplify the chemoanalytical process in identifying aromas and smells. Whereas numerous odor-active substance classes have been investigated intensively, such relationships and fundamental data have hithert...

355

Lactate and amino acid catabolism in the cheese-ripening yeast Yarrowia lipolytica.  

The consumption of lactate and amino acids is very important for microbial development and/or aroma production during cheese ripening. A strain of Yarrowia lipolytica isolated from cheese was grown in a liquid medium containing lactate in the presence of a low (0.1x) or high (2x) concentration of amino acids. Our results show that there was a dramatic increase in the growth of Y. lipolytica in the medium containing a high amino acid concentration, but there was limited lactate consumption. Conversely, lactate was efficiently consumed in the medium containing a low concentration of amino acids after amino acid depletion was complete. These data suggest that the amino acids are used by Y. lipolytica as a main energy source, whereas lactate is consumed following amino acid depletion. Amino acid degradation was accompanied by ammonia production corresponding to a dramatic increase in the pH. The effect of adding amino acids to a Y. lipolytica culture grown on lactate was also investigated. Real-time quantitative PCR analyses were performed with specific primers for five genes involved in amino acid transport and catabolism, including an amino acid transporter gene (GAP1) and four aminotransferase genes (ARO8, ARO9, BAT1, and BAT2). The expression of three genes involved in lactate transport and catabolism was also studied. These genes included a lactate transporter gene (JEN1) and two lactate dehydrogenase genes (CYB2-1 and CYB2-2). Our data showed that GAP1, BAT2, BAT1, and ARO8 were maximally expressed after 15 to 30 min following addition of amino acids (BAT2 was the most highly expressed gene), while the maximum expression of JEN1, CYB2-1, and CYB2-2 was delayed (>or=60 min). PMID:18776032

356

Chemical and sensory characteristics of pulp and peel 'cajá-manga' (Spondias cytherea Sonn.) jelly/ Caracterização química e sensorial de geléia da casca e polpa de cajá-manga (Spondias cytherea Sonn.)  

Abstract in portuguese O cajá-manga (Spondias cytherea) é uma fruta com aroma intenso e sabor agridoce, sendo, por isto, bastante apreciado. Sua casca, embora mais fibrosa, é tenra e muitas vezes consumida juntamente com a polpa. A casca é uma parte do alimento normalmente desprezada, mas, muitas vezes, é rica em sabor e fibras, representando uma opção na formação de novos alimentos. Em função de não haver na literatura relato do aproveitamento da casca de cajá-manga para a elabora (more) ção de geleia, este trabalho teve por objetivo desenvolver e avaliar este produto. Através dos resultados, constatou-se que as cascas apresentaram maiores teores de proteína, lipídios, cinzas, fibra alimentar, carboidratos totais e pectina e menor teor de umidade em relação à polpa de cajá-manga. A geleia de casca e da polpa (controle) apresentaram as seguintes características físico-químicas: umidade, 29,5 e 34,2%; proteínas, 0,19 e 0,27%; lipídios, 0,11 e 0,16%; açúcares totais, 56,5 e 65,5%; e sólidos solúveis totais, 69 e 66 ºBrix, respectivamente. A análise sensorial indicou que o produto elaborado a partir da casca apresentou aceitação satisfatória para todos os atributos avaliados: aparência, cor, odor, textura, sabor e avaliação global. Conclui-se que a substituição total da polpa por cascas na formulação resulta em produto de bom valor nutricional sem prejuízos sensoriais. Abstract in english Cajá-manga (Spondias cytherea) is a fruit with intense aroma and a sweet sour taste, thus being very appreciated. Its peel, in spite of being more fibrous, is tender and many times consumed with the pulp. The peel is a part of foods normally discarded, but many times, it is rich in taste and fibers, representing an option at the elaboration of new foods. Since there are no reports in the literature on the use of cajá-manga peel for jelly making, this work had the purpos (more) e of developing and evaluating this product. Based on the results, it was noted that the peels presented higher contents of protein, lipids, ashes, food fiber, total carbohydrates and pectin, and lower content of moisture, when compared to the pulp. The peel and the pulp (control) jellies presented the following physical-chemical characteristics: moisture, 29.5 and 34.2%; proteins, 0.19 and 0.27%; lipids, 0.11 and 0.16%; total sugars, 56.5 and 65.5%; and total soluble solids, 69 and 66 ºBrix, respectively. The sensory analysis indicated that the product elaborated from the peel presented satisfactory acceptance for all the assessed attributes: appearance, color, odor, texture, taste and global evaluation. It is concluded that the total substitution of the pulp by the peel in the formulation, results in a product with good nutritional value with no sensory damages.

357

Influência de diferentes agentes de corpo nas características reológicas e sensoriais de chocolates diet em sacarose e light em calorias/ Influence of different bulk agents in the rheological and sensory characteristics of diet and light chocolate  

Abstract in portuguese Foram estudados diferentes agentes de corpo na substituição total da sacarose na formulação de chocolate, buscando-se obter um produto diet em sacarose e light em calorias (25% de redução calórica teórica em relação à formulação padrão, com sacarose) e com boa aceitação sensorial. Os agentes de corpo utilizados neste estudo foram: polidextrose, inulina, frutooligossacarídeos - FOS, lactitol e maltitol; como edulcorante de alta intensidade empregou-se a su (more) cralose. Os chocolates light obtidos foram submetidos às análises de umidade (Karl Fisher), tamanho de partículas (micrômetro digital) e propriedades reológicas (viscosidade plástica - etaca e limite de escoamento de Casson - tauca). O teor de umidade dos chocolates light variou de 1,23 a 2,12%; o tamanho de partículas de 19 a 24 µm; o etaca de 6,60 a 11,00 Pa.s; e o tauca de 0,05 a 1,31 Pa. As formulações com polidextrose, polidextrose e lactitol e polidextrose e maltitol foram selecionadas para análise sensorial por apresentarem boa performance tecnológica e adequada maquinabilidade da massa de chocolate durante as diferentes etapas do processo. A análise sensorial indicou que as três formulações avaliadas não diferiram entre si ao nível de significância de 5% em relação à intensidade do aroma, dureza, derretimento na boca e sabor e, quanto à intenção de compra, as amostras diferiram entre si ao nível de significância de 5%, sendo que a formulação que continha 32,60% de Polidextrose e 15,57% de Maltitol foi a preferida. Abstract in english A study was made of various bulk agents as sucrose substitutes in the formulation of chocolate, aiming to obtain a diet product in terms of sucrose and a light product in terms of calories (25% fewer calories than standard formulations containing sucrose) with good sensorial acceptance. The bulk agents used in this study were polydextrose, inulin, fructo-oligosaccharides - FOS, lactitol and maltitol. Sucralose was used as a high intensity sweetener. The light chocolates w (more) ere analyzed for moisture content (Karl Fischer), particle size (digital micrometer), and rheological properties (Casson plastic viscosity, etaca, and yield strength, tauca). The moisture content of the light chocolate varied from 1.23 to 2.12%, while particle size varied from 19 to 24 µm, etaca from 6.60 to 11.00 Pa.s, and tauca from 0.05 to 1.10 Pa. The formulations containing polydextrose, polydextrose and lactitol, and polydextrose and maltitol were selected for a sensory analysis due to their good technological performance and adequate machinability of the chocolate mass in the different stages of the process. The sensory analysis revealed no statistically significant difference (p > 0.05) in the three evaluated formulations in terms of aroma, hardness, melting in the mouth and flavor. There was no statistically significant difference (p > 0.05) in the intention to purchase the three chocolate formulations, although a preference was shown for the formulation containing polydextrose (32.60%) and maltitol (15.57%).

358

Double Schiff Base Adducts of 2,3-Butanedione with Glycine: Formation of Pyrazine Rings with the Participation of Amino Acid Carbon Atoms.  

The 1,2-dicarbonyl compounds are well-known for their ability to undergo a one-to-one interaction with amino acids and generate aroma-active pyrazines through the Strecker reaction. An earlier publication reported the generation of tetrahydropyrazine moiety from the double addition of amino acids to 1,2-dicarbonyl compounds. To evaluate the potential of this intermediate to undergo oxidation and form pyrazines, a model system composed of glycine and 2,3-butanedione was evaluated under pyrolytic conditions at 250 °C, as well as under pressurized high-temperature conditions at 120 °C. These studies have indicated the unexpected formation of 2,3-dimethylpyrazine and 2,3,5-trimethylpyrazine in addition to the expected tetramethylpyrazine. Isotope-labeling studies using [(13)C-1]glycine (98%), [(13)C-2]glycine (99%), and [(15)N]glycine (98%) have shown that, as expected, tetramethylpyrazine was completely unlabeled, whereas 51% of 2,3-dimethylpyrazine incorporated two (13)C-2 atoms from glycine, 20% incorporated one atom, and 29% was unlabeled. Furthermore, the label incorporation pattern in the major mass spectral fragment at m/z 67 indicated that the C-2 atoms originating from glycine reside in the ring system of 2,3-dimethylpyrazine. The formation of doubly labeled 2,3-dimethylpyrazine was rationalized through proposition of the double addition of glycine to 2,3-butanedione, and the formation of singly labeled isotopomer was justified by sequential Schiff base formation of 2-amino-butan-3-one first with the Strecker aldehyde and then followed by glycine. This pathway can also generate the double-labeled pyrazine. Finally, the unlabeled pyrazine was proposed to form through the Strecker reaction of 2,3-butanedione and its degradation product glyoxal with glycine. The proposed pathways were also consistent with the observed label distribution patterns of 2,3,5-trimethylpyrazine. PMID:23106172

359

Functional characterization of enone oxidoreductases from strawberry and tomato fruit.  

Fragaria x ananassa enone oxidoreductase (FaEO), earlier putatively assigned as quinone oxidoreductase, is a ripening-induced, negatively auxin-regulated enzyme that catalyzes the formation of 4-hydroxy-2,5-dimethyl-3(2H)-furanone (HDMF), the key flavor compound in strawberry fruit by the reduction of the alpha,beta-unsaturated bond of the highly reactive precursor 4-hydroxy-5-methyl-2-methylene-3(2H)-furanone (HMMF). Here we show that recombinant FaEO does not reduce the double bond of straight-chain 2-alkenals or 2-alkenones but rather hydrogenates previously unknown HMMF derivatives substituted at the methylene functional group. The furanones were prepared from 4-hydroxy-5-methyl-3(2H)-furanone with a number of aldehydes and a ketone. The kinetic data for the newly synthesized aroma-active substrates and products are similar to the values obtained for an enone oxidoreductase from Arabidopsis thaliana catalyzing the alpha,beta-hydrogenation of 2-alkenals. HMMF, the substrate of FaEO that is formed during strawberry fruit ripening, was also detected in tomato and pineapple fruit by HPLC-ESI-MSn and became 13C-labeled when d-[6-13C]-glucose was applied to the fruits, which suggested that a similar HDMF biosynthetic pathway occurs in the different plant species. With a database search (http://ted.bti.cornell.edu/ and http://genet.imb.uq.edu.au/Pineapple/), we identified a tomato and pineapple expressed sequence tag that shows significant homology to FaEO. Solanum lycopersicon EO (SlEO) was cloned from cDNA, and the protein was expressed in Escherichia coli and purified. Biochemical studies confirmed the involvement of SlEO in the biosynthesis of HDMF in tomato fruit. PMID:17636940

360

Chemical characterization of sicilian prickly pear (Opuntia ficus indica) and perspectives for the storage of its juice.  

In this work, Sicilian cultivars of prickly pear (Opuntia ficus indica) were partially characterized from a chemical point of view, and the possibility of long-term storage of their juice was investigated. The acidity of the prickly pear juice turned out to be very low (0.02%) and the pH very high (6.4-6.5) if compared with values found in other common fruit juices. In the perspective of processing and storage conditions according to Italian law, the acidity has been corrected by adding the proper amount of tartaric and/or phosphoric acid. The sugar content (mainly glucose and fructose) is very high (11-12%), and also L-ascorbic acid is present in considerable amount (31-38 mg/100 g). Among the transition metals, a high content of manganese(II) (1.7-2.9 ppm) and good amounts of iron(III) (0.6-1.2 ppm) and zinc(II) (0.3-0.4 ppm) were found. In particular, such ions appear to be present mainly in the thick skin of the fruit or "trapped" inside the pulp. Pectin methylesterase (PME) seems to be present in very small amount and/or is not highly active. Furthermore, PME activity decreases considerably after the necessary adjustment of the pH and the thermal treatment requested for long-term storage. After approximately 2 months, none of the juices prepared was affected by noticeable sedimentation of the pulp. Finally, different samples of prickly pear juice were sensorially analyzed, employing descriptors such as color, aroma, viscosity, acidity, sweetness, and off-flavors. The results obtained can be considered very satisfactory, and the juice has been widely appreciated when compared with other products commonly available on the market such as pear and peach juices. PMID:11087496

 
 
 
 
361

Genetic and chemical diversity of citron (Citrus medica L.) based on nuclear and cytoplasmic markers and leaf essential oil composition.  

Native to southeast Asia, the citron (Citrus medica L.) was the first citrus fruit to be introduced to the Mediterranean area, in the third century BC, and remained its only citrus representative until the tenth century. The citron was used for its aroma - stemming from its essential oils in leaves and fruit peels - and as symbols in the Jewish religion. Subsequently, the cultivation of citron was extended significantly, peaking in the nineteenth century, when its fruits were used in cosmetics and confectioneries. The objective of this study was to examine the genetic diversity of the Mediterranean citron with regard to the multiplication and dissemination practices that were related to its uses. We studied the polymorphisms of 27 nuclear and cytoplasmic genetic markers of 24 citron varieties, preserved in the citrus germplasm of INRA-CIRAD, San Giuliano, France. The composition of leaf essential oils was determined to establish varieties and phylogenic relationships between accessions. Other major citrus species were included in the molecular analysis, which demonstrated the existence of 13 genetically linked citrons, differing from other citrus species, based on low heterozygosity and specific alleles; these citrons were considered true-type citrons, confirmed by their convergent chemical profiles. We also detected a polymorphism in the chloroplastic genome in these 13 citrons, which, when combined with allelic diversity of 2.4 alleles per locus, suggests that multiple citrons were introduced to the Mediterranean area in last 2 millennia. We determined the genetic origin and relationships of several varieties, such as Corsican, which could have arisen from the selfing of Poncire Commun. We noted a higher-than-expected polymorphism rate among Mediterranean citron varieties, likely due to crossfecundation. The chemical leaf oil composition of several economical varieties, such as Corsican, is distinct and can increase the quality of specific agriculture products for the cosmetics and candy industries. PMID:22264998

362

Floral Benzenoid Carboxyl Methyltransferases: From in Vitro to in Planta Function  

Benzenoid carboxyl methyltransferases synthesize methyl esters (e.g., methyl benzoate and methyl salicylate), which are constituents of aromas and scents of many plant species and play important roles in plant communication with the surrounding environment. Within the past five years, eleven such carboxyl methyltransferases were isolated and most of them were comprehensively investigated at the biochemical, molecular and structural level. Two types of enzymes can be distinguished according to their substrate preferences: the SAMT-type enzymes isolated from Clarkia breweri, Stephanotis floribunda, Antirrhinum majus, Hoya carnosa, and Petunia hybrida, which have a higher catalytic efficiency and preference for salicylic acid, while BAMT-type enzymes from A. majus, Arabidopsis thaliana, Arabidopsis lyrata, and Nicotiana suaveolens prefer benzoic acid. The elucidation of C. breweri SAMT's three-dimensional structure allowed a detailed modelling of the active sites of the carboxyl methyltransferases and revealed that the SAM binding pocket is highly conserved among these enzymes while the methyl acceptor binding site exhibits some variability, allowing a classification into SAMT-type and BAMT-type enzymes. The analysis of expression patterns coupled with biochemical characterization showed that these carboxyl methyltransferases are involved either in floral scent biosynthesis or in plant defense responses. While the latter can be induced by biotic or abiotic stress, the genes responsible for floral scent synthesis exhibit developmental and rhythmic expression pattern. The nature of the product and efficiency of its formation in plants depend on the availability of substrates, the catalytic efficiency of the enzyme toward benzoic acid and/or salicylic acid, and the transcriptional, translational, and post-translational regulation at the enzyme level. The biochemical properties of benzenoid carboxyl methyltransferases suggest that the genes involved in plant defenses might represent the ancestor for the presently existing floral genes which during evolution gained different expression profiles and encoded enzymes with the ability to accept structurally similar substrates.

363

Bactérias do acido láctico e leveduras associadas com o queijo-de-minas artesanal produzido na região da Serra do Salitre, Minas Gerais/ Lactic acid bacteria and yeasts associated with the artisanal Minas cheese produced in the region of Serra do Salitre, Minas Gerais  

Abstract in portuguese Em 10 fazendas da região da Serra do Salitre, MG, foram coletadas amostras de leite, soro fermentado (pingo), coalhada e queijo frescal para avaliar a microbiota de bactérias láticas e leveduras presentes. Uma diversidade menor de bactérias láticas foi observada durante a produção do queijo quando comparada à de leveduras. As espécies de bactérias láticas mais freqüentes foram Lactococcus lactis, Enterococcus spp., Enterococcus faecalis e Streptococcus agalact (more) iae e de leveduras foram Debaryomyces hansenii e Kluyveromyces lactis. Apenas as populações de Enterococcus spp., Enterococcus faecalis e Leuconostoc mesenteroides apresentaram aumento significativo durante a produção do queijo. As espécies de bactérias láticas e leveduras encontradas nos diferentes substratos estudados podem ser responsáveis pelas características de aroma e sabor do queijo artesanal da Serra do Salitre. Abstract in english Samples of milk, curd, cheese whey, and cheese were collected in 10 farms located at the region of Serra do Salitre, Minas Gerais state. These samples were studied in relation to their lactic acid bacteria and yeast populations. The diversity of lactic acid bacteria species was lower than the diversity of yeasts in these samples. The isolated lactic acid bacteria were Lactococcus lactis, Enterococcus spp., Enterococcus faecalis, and Streptococcus agalactiae; and the yeast (more) s were Debaryomyces hansenii and Kluyveromyces lactis. Only the species Enterococcus spp., Enterococcus faecalis, and Leuconostoc mesenteroides showed an increase in their populations during the production of the artisanal cheese. Lactic acid bacteria and yeasts found in this study could be responsible by the sensorial characteristics of the artisanal cheese produced in the region of Serra do Salitre.

364

Production of ingredient-type cheddar cheese with accelerated flavor development by addition of enzyme-modified cheese powder.  

Fast-ripened Cheddar cheeses for ingredient purposes were produced by addition of a dried enzyme-modified cheese (EMC; 0.25 and 1 g/100 g of milled curd) at the salting stage during a standard Cheddar cheese-making procedure. Populations of starter and nonstarter lactic acid bacteria (NSLAB), levels of proteolysis and lipolysis, volatile analysis, and flavor development (by quantitative descriptive sensory analysis) were monitored over a 6-mo ripening period. Levels of free AA and free fatty acids were elevated in the experimental cheeses on d 1 because of inclusion of the EMC. Counts of NSLAB were also elevated in the experimental cheeses compared with the control cheese from the start of ripening. Levels of free AA were slightly elevated in the experimental cheeses at 1, 2, and 4 mo, but significantly greater accumulations were detected by 6 mo of ripening, with His, Leu, and glutamate reflecting the greatest increases. Levels of long-chain free fatty acids increased up to 2 mo, indicating an initial stimulation of lipolysis, but had decreased by 6 mo, indicating greater catabolism, probably caused by NSLAB and increased starter lysis. Principal component analysis of the volatile compounds showed few differences in the aroma profiles among the cheeses up to 4 mo of ripening, but a large separation of the cheeses supplemented with EMC relative to the control was observed by 6 mo. Sensory analysis of the cheeses with added EMC showed an acceleration of 2 mo in flavor development compared with the control cheese with the addition of 1 g/100 g of EMC developing a flavor profile at 4 mo similar to the control cheese at 6 mo of ripening. However, atypical Cheddar flavors developed on prolonged storage. This study shows the potential of adding EMC during Cheddar production to produce a fast-ripened ingredient-type Cheddar cheese. PMID:16960049

365

Oxidative stability and consumer acceptance of fish oil fortified nutrition bars.  

Oat and soy-based nutrition bars were fortified with 4 levels of fish oil (0, 6, 12, or 18 g per approximately 600 g batch), representing 0%, 20%, 40%, or 60% replacement of canola oil. The commercially available purified fish oil was not emulsified nor encapsulated, and contained tocopherols. Baked nutrition bars were evaluated for proximate composition, water activity, alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic (DHA) content, and consumer acceptance using a 9-point hedonic scale. The bars were sealed in opaque bags and stored in a stability chamber at 25 °C and 50% relative humidity for 10 wk to assess oxidative stability. There were no significant (P > 0.05) differences in proximate composition, water activity, or ALA levels among treatments. EPA and DHA levels were significantly (P Peroxide values were not significantly different except between the control and 60-FO bars. Low values obtained for these analyses suggest negligible oxidation in the bars. Consumer acceptance scores did not differ significantly between the control and lowest fortification level (20-FO), ranging from 6.4 to 6.6 for aroma, texture, flavor, and overall acceptability. These results suggest that nonemulsified, nonencapsulated fish oil can successfully replace canola oil in intermediate moisture nutrition bars to provide EPA and DHA levels as high as 178 mg/serving without affecting consumer acceptability or oxidative stability. PRACTICAL APPLICATION: Omega-3 fatty acid rich fish oil has been shown to have numerous health benefits, but there are limitations to its use in shelf-stable food products. In this study, nutrition bars were successfully fortified with nonencapsulated, nonemulsified fish oil to deliver 178 mg EPA and DHA per 35 g serving. The fortified bars were oxidatively stable over 10 wk and acceptable to consumers. PMID:22957916

366

Main odorants in Jura flor-sherry wines. Relative contributions of sotolon, abhexon, and theaspirane-derived compounds.  

The aromatic profile of Jura flor-sherry wines (also called "yellow wines") has been little studied. Only acetaldehyde, diethoxy-1,1-ethane, and sotolon have been described as key odorants. In the present work, three wines (vintages 2002 and 2003) were investigated by gas chromatography-mass spectrometry and gas chromatography-olfactometry (GC-O) aroma extract dilution analysis. The goal was to assess the relative impact of varietal, fermentation, and oak-barrel compounds by using two complementary extraction procedures. No grape terpenoids were found after the long barrel aging (6 years and 3 months). On the other hand, two candy/fruity esters issued from yeast exhibited high flavor dilution factor (FD) values: ethyl isobutyrate (64-1024) and ethyl isovalerate (128-1024). As expected, many oak-related odorants were found in the XAD 2 flavor extracts, mainly homofuraneol [2-ethyl-4-hydroxy-5-methyl-3(2H)-furanone] (cotton candy, FD = 16-256) and cis-?-methyloctalactone (butter, woody, FD = 256). Most probably issued from oxidation of the grape constituent theaspirane, an exceptional grenadine odor was perceived by GC-O up to dilution 64-1024. Chemical oxidation experiments and GC-high-resolution mass spectrometry (HRMS) allowed us to identify it as 4-hydroxy-7,8-dihydro-?-ionone (RI(CPsil5CB) = 1373), a hydrolysis-derived product of dihydrodehydro-?-ionone. With an extraction dedicated to hydrophilic compounds, the key role of sotolon was confirmed (112-387 ?g/kg; FD = 256-1024). This procedure enabled us to also evidence its ethyl analogue, abhexon (31-74 ?g/kg; FD = 64-256). PMID:22117650

367

Isolation and characterization of two hydroperoxide lyase genes from grape berries : HPL isogenes in Vitis vinifera grapes.  

C6 compounds are the major fraction of the volatile profiles of grape berries, contributing the typical 'green' aroma to the grape and wine. Hydroperoxide lyase (HPL) catalyzes the cleavage of fatty acid hydroperoxides to produce C6 compounds. Two hypothetical genes, VvHPL1 and VvHPL2 were cloned from grape berries (Vitis vinifera L. Cabernet Sauvignon). Bioinformatics analysis revealed that the proteins encoded by these two genes both belong to subfamily of cytochrome P450 and contain typical conserved domains of HPLs, and have high identity with HPLs from other plants. Prokaryotically-expressed VvHPL1 and VvHPL2 with thioredoxin-6xHis-fusion partner were confirmed to have enzymatic activity. VvHPL1 is specific for 13-HPOD (T) producing C6 aldehydes with relatively higher activity and VvHPL2 catalyzes the cleavage of both 9- and 13-hydroperoxides producing C6 aldehydes and C9 aldehydes respectively. Analysis of real time-PCR showed that VvHPL2 was highly expressed in the leaves and the flowers of the grapes, while relatively low transcript abundance was detected in the berries, tendril and stems; VvHPL1 had high expression in all detected tissues. During grape berry development, the expression of these two isogenes presented similar trends with a rapid increase after veraison and a decrease at full-ripen stage, which roughly corresponded to the accumulation of their volatile products. These data lay an essential foundation for further study on the accumulation and control of C6 volatiles in grape berries. PMID:22318551

368

Perfil sensorial e aceitabilidade de méis de abelhas sem ferrão submetidos a processos de conservação/ Sensorial profile and acceptability of stingless bee honey submitted to conservation processes  

Abstract in portuguese O presente trabalho avaliou o perfil sensorial e a aceitabilidade de méis de abelhas sem ferrão submetidos a dois processos de conservação, objetivando obter maior vida de prateleira. Foram utilizadas amostras de méis de Melipona scutellaris e M. quadrifasciata, coletadas no Estado da Bahia entre dezembro de 2005 e janeiro de 2006. As amostras foram submetidas aos processos de pasteurização e desumidificação, passando em seguida por avaliação sensorial. O perfi (more) l sensorial foi determinado no Laboratório de Entomologia do Centro de Ciências Agrárias, Ambientais e Biológicas da Universidade Federal do Recôncavo da Bahia, em Cruz das Almas, Estado da Bahia. Os atributos analisados foram: fluidez, cor, aroma, cristalização, sabor e aceitabilidade. Os resultados mostraram que os processos de conservação utilizados não interferem no perfil sensorial e na aceitabilidade do produto. Abstract in english The present work was conducted to evaluate the sensorial profile and the acceptability of the honey of stingless bees submitted to two conservation processes seeking to obtain longer shelf life. The samples of Melipona scutellaris and M. quadrifasciata honey were collected in the State of Bahia, Brazil, between December 2005 and January 2006. The samples were first submitted to pasteurization and dehumidification processes and then to sensorial evaluation. The sensorial p (more) rofile was determined in the Laboratory of Entomology in the Center for Agrarian, Biological, and Environmental Sciences of the Federal University of Recôncavo Bahiano, in Cruz das Almas, in the state of Bahia. The analyzed attributes were: fluidity, color, scent, crystallization, flavour, and acceptability. The results show that the conservation processes used do not interfere with the sensorial profile and the product acceptability.

369

Manipulating volatile emission in tobacco leaves by expressing Aspergillus nigerbeta-glucosidase in different subcellular compartments.  

Expression of the Aspergillus nigerbeta-glucosidase gene, BGL1, in Nicotiana tabacum plants (cv. Xanthi) had a profound effect on the volatile emissions of intact and crushed leaves. BGL1 was expressed under the control of the cauliflower mosaic virus (CaMV) 35S promoter and targeted to the cytoplasm, cell wall, lytic vacuole (LV), chloroplast or endoplasmic reticulum (ER). Subcellular localization was confirmed by gold immunolabelling, followed by transmission electron microscopy (TEM). Significant beta-glucosidase activity was observed in transgenic plants expressing BGL1 in the cell wall, LV and ER. Compared with controls, all intact transgenic leaves were found to emit increased levels of 2-ethylhexanol, as determined by gas chromatography-mass spectrometry (GC-MS) analysis of the headspace volatiles. Plants expressing BGL1 in the cell wall (Tcw) emitted more trans-caryophyllene than did non-transgenic controls, whereas plants expressing BGL1 in the ER (Ter) and LV (Tvc) emitted more cembrene than did non-transgenic controls. Volatiles released from crushed transgenic leaves and collected with solid-phase microextraction (SPME) polydimethylsiloxane fibre were distinctly enhanced. Significant increases in linalool, nerol, furanoid cis-linalool oxide, 4-methyl-1-pentanol, 6-methyl-hept-5-en-2-ol and 2-ethylhexanol were detected in transgenic plants when compared with wild-type controls. 3-Hydroxyl-beta-ionone levels were increased in crushed Tcw and Ter leaves, but were undetectable in Tvc leaves. The addition of glucoimidazole, a beta-glucosidase inhibitor, abolished the increased emission of these volatiles. These results indicate that the expression of a fungal beta-glucosidase gene in different subcellular compartments has the potential to affect the emission of plant volatiles, and thereby to modify plant-environment communication and aroma of agricultural products. PMID:17134395

370

Stability of fruit bases and chocolate fillings/ Estabilidade de bases de frutas e recheios para chocolates  

Abstract in portuguese Xaropes com alto conteúdo de açúcar e frutas desidratadas podem ser adicionados a recheios de produtos de chocolate a fim de reduzir a necessidade da adição de aromas e corantes, atribuindo um apelo natural ao produto. Foram produzidas bases de frutas e recheios com morango e maracujá liofilizados e casca de laranja in natura. Testes reológicos de oscilação foram usados para determinar a estabilidade do produto e tendência de vida de prateleira. Valores de G´(more) G´´ foram observados para as bases de morango e maracujá, enquanto para a de laranja obtiveram-se valores G´ > G´´ durante 90 dias de armazenamento. Observou-se que valores de tensão de cisalhamento não variaram significantemente, sugerindo a estabilidade dos produtos durante o período estudado. Para todos os recheios, foi obtido comportamento semelhante ao das bases, indicando que estas estabelecem grande influência no comportamento e estabilidade dos recheios. O uso da matriz de açúcar colaborou com um prolongamento da vida de prateleira da base de fruta, que conseguiu manter o produto final armazenado em temperatura ambiente por período acima de um ano. A boa estabilidade e condições de armazenamento permitem o uso das bases de frutas em produções artesanais e industriais. Abstract in english Syrups with high sugar content and dehydrated fruits in its composition can be added to chocolate fillings to reduce the need of artificial flavor and dyes attributing a natural appeal to the product. Fruit bases were produced with lyophilized strawberry, passion fruit, and sliced orange peel. Rheological dynamic oscillatory tests were applied to determine the products stability and tendency of shelf life. Values of G´(more) t flavor, whereas values of G´ > G´´ were found for orange flavor during the 90 days of storage. It was observed that shear stress values did not vary significantly suggesting product stability during the studied period. For all fillings, it was found a behavior similar to the fruit base indicating that it has great influence on the filling behavior and its stability. The use of a sugar matrix in fillings provided good shelf life for the fruit base, which could be kept under room temperature conditions for a period as long as one year. The good stability and storage conditions allow the use of fruit base for handmade products as well as for industrialized products.

371

Estabilidade de pasta de amêndoa de castanha de caju/ Stability of cashew nut butter  

Abstract in portuguese O presente trabalho visou avaliar a estabilidade de pasta de castanha de caju obtida pela moagem de amêndoas quebradas com açúcar, sal e lecitina de soja. A influência de diferentes embalagens (potes de vidro e de polipropileno) e do uso de antioxidantes (BHA, BHT e tocoferóis) na qualidade do produto também foi investigada. Características físico-químicas (atividade de água, índice de acidez, cor e textura instrumentais), microbiológicas (coliformes totais e (more) fecais, Escherichia coli, Salmonella spp., Staphylococcus coagulase positiva e bolores e leveduras) e aceitação sensorial (aparência, aroma, sabor e textura), foram acompanhadas durante 300 dias de armazenamento à temperatura ambiente (28 °C). Foi observado aumento do índice de acidez, redução da maciez e descoloração. No entanto, essas alterações pouco afetaram a aceitação sensorial, que ficou entre "gostei ligeiramente" e "gostei moderadamente", após os 300 dias de armazenamento. As análises microbiológicas demonstraram boa qualidade do produto, estando dentro dos padrões exigidos pela legislação brasileira: contagem de coliformes a 45 °C (fecais) menor que 10 NMP.g -1 e ausência de Salmonella spp. em 25 gramas. Os resultados demonstraram que as pastas podem ser armazenadas nas condições e tempo testados, e que não houve influência dos materiais de embalagem utilizados e nem dos antioxidantes na estabilidade do produto. Abstract in english This work involved an evaluation of the stability of cashew nut butter obtained by grinding up broken cashew kernels with sugar, salt and soy lecithin. The influence of different packaging materials (glass and polypropylene containers) and antioxidants (BHA, BHT and tocopherols) on product quality was also evaluated. Physicochemical (water activity, acidity index, instrumental color and texture) and microbiological characteristics (total and fecal coliforms, Escherichia c (more) oli, Salmonella spp., coagulase-positive staphylococci, yeast and mold) and sensory acceptance (appearance, flavor, taste and texture) were monitored during 300 days of storage at room temperature (28 °C). The findings indicated an increase in the acidity index, a decline in smoothness and discoloration. However, these alterations hardly affected the sensory acceptance, which, after 300 days of storage, was expressed as "I like it a little" and "I like it moderately". The microbiological analyses showed good product quality at the end of the storage period, since the product met the specifications of Brazilian regulations, i.e., a maximum of 10 MPN.g -1 of fecal coliforms (at 45 °C) and absence of Salmonella spp. in 25 g of product. The results indicated that cashew nut butter can be stored for the time period and under the conditions tested here and that the packaging material and antioxidants utilized did not affect the product's stability.

372

Further insights into the floral character of Touriga Nacional wines.  

Higher-quality Touriga Nacional (TN) wines are characterized by a fruity-citric aroma described as sweet and fresh citrus evoking the bergamot fruit (Citrus bergamia). In fact, "bergamot-like" descriptor is currently employed to rate higher quality TN wines. The aim of this work was to identify among volatile compounds present in bergamot fruit extracts (mainly terpenes) which of them contributes the most to the bergamot overall perception, and relate these data with the volatile composition of TN wines. The identification of the most important descriptors was done by sensory analysis. Among 18 descriptors 3 were selected: bergamot-like aroma, orange like, and violet. A GCO of a typical TN wine extract allows the identification of 3 related odorant zones ZO1, ZO2, and ZO3 related with bergamot-like aroma. Using AEDA, ZO2 was confirmed to be one of the most important odorant zones. Using AEDA the presence of linalool and linalyl acetate was confirmed. A similarity test was performed with a non-TN wine added with linalool and linalyl acetate alone or in combinations. The highest similarity value was observed when linalool (SV = 5.9) was added. In fact, results obtained from the analysis of several red wines from different varieties show that terpenols are present in higher amounts in wines coming from TN variety, which proves that these compounds can be the clue to the varietal aroma of TN wines. PMID:17995696

373

Fungi of Mt. Babia Gora. 1: Mycoflora of forests  

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