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Impact of a Non-Saccharomyces Yeast Isolated in the Equatorial Region in the Acceptance of Wine Aroma  [PDF]
Mariana Oliveira Assis, Adriana Pereira Coelho Santos, Carlos Augusto Rosa, Maria Eugênia de Oliveira Mamede
Food and Nutrition Sciences (FNS) , 2014, DOI: 10.4236/fns.2014.59086
Abstract:

The aim of this work was to isolate and identify the yeasts prevalent in fresh grapes cultivated in the “São Francisco Valley” region (Brazil), as well as evaluating the cell growth of these indigenous yeasts during the fermentation of grape musts and their contribution to the improvement of wine aroma. The Chenin Blanc grape must fermented by H. opuntiae presented higher acceptance means at the three points analyzed (6.74, 6.78 and 7.30) and in the fermentation carried out by the yeasts H. opuntiae and S. cerevisiae, the highest mean acceptance (7.22) was observed after 120 hours, with no statistical difference from the sample fermented by H. opuntiae alone. Since these samples that showed higher acceptance means also receiving higher scores for purchasing intention, corresponding to the concepts of “definitely would buy” and “probably would buy”. The present study suggests that the fermentations of grape musts carried out by the yeast H. opuntiae and mixed cultures of H. opuntiae and Saccharomyces cerevisiae, positively influenced the sensory qualities of the wines and showed greater potential to increase the aroma of the musts and to develop specific wine styles.

INFLUENCE OF DIFFERENT OAK CHIPS ON AROMA COMPOUNDS IN WINE  [PDF]
Jana Návojská,Walter Brandes,Stefan Nauer,Reinhard Eder
Journal of Microbiology, Biotechnology and Food Sciences , 2012, DOI: 13385178
Abstract: Oak wood has considerable influence on amount of aroma compounds in wine. During the time, when wine is in contact with oak wood, compounds typical for wood diffuse into wine and enrich its aromatic complexity. Concentration of diffused aroma compounds in wine depends on several factors as contact time, storage conditions, wine properties, geographical origin and toasting degree of oak wood. Because of very small quantities of volatile aroma compounds in wine, it is necessary to use sensitive method as gas chromatography with appropriate sample preparation, to concentrate and analyse the relevant volatiles. In our work, four different wines and eight chips samples with different geographic origin and degree of toasting were used. With GC-MS following substances were determined in wines after 30 days of maceration with oak chips: furfural, 5-methylfurfural, guaiacol, 4-ethylguaiacol, eugenol, isoeugenol, cis- and trans-whiskey lactones, 4-ethylphenol. Our results show, that the degree of toasting influences the concentration of furfural, guaiacol and cis- and trans- whiskeylactone. Higher toasting leads to an increase of furfural and guaiacol and a decrease of cis- and trans-whiskeylactone in wine. The highest increase of volatile aroma compounds was determined in wine samples with French oak chips with intense toasting. We did not find any specific, definite differences among chips with different geographic origin.
Introducing a New Breed of Wine Yeast: Interspecific Hybridisation between a Commercial Saccharomyces cerevisiae Wine Yeast and Saccharomyces mikatae  [PDF]
Jennifer R. Bellon, Frank Schmid, Dimitra L. Capone, Barbara L. Dunn, Paul J. Chambers
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0062053
Abstract: Interspecific hybrids are commonplace in agriculture and horticulture; bread wheat and grapefruit are but two examples. The benefits derived from interspecific hybridisation include the potential of generating advantageous transgressive phenotypes. This paper describes the generation of a new breed of wine yeast by interspecific hybridisation between a commercial Saccharomyces cerevisiae wine yeast strain and Saccharomyces mikatae, a species hitherto not associated with industrial fermentation environs. While commercially available wine yeast strains provide consistent and reliable fermentations, wines produced using single inocula are thought to lack the sensory complexity and rounded palate structure obtained from spontaneous fermentations. In contrast, interspecific yeast hybrids have the potential to deliver increased complexity to wine sensory properties and alternative wine styles through the formation of novel, and wider ranging, yeast volatile fermentation metabolite profiles, whilst maintaining the robustness of the wine yeast parent. Screening of newly generated hybrids from a cross between a S. cerevisiae wine yeast and S. mikatae (closely-related but ecologically distant members of the Saccharomyces sensu stricto clade), has identified progeny with robust fermentation properties and winemaking potential. Chemical analysis showed that, relative to the S. cerevisiae wine yeast parent, hybrids produced wines with different concentrations of volatile metabolites that are known to contribute to wine flavour and aroma, including flavour compounds associated with non-Saccharomyces species. The new S. cerevisiae x S. mikatae hybrids have the potential to produce complex wines akin to products of spontaneous fermentation while giving winemakers the safeguard of an inoculated ferment.
QTL mapping of the production of wine aroma compounds by yeast  [cached]
Steyer Damien,Ambroset Chloe,Brion Christian,Claudel Patricia
BMC Genomics , 2012, DOI: 10.1186/1471-2164-13-573
Abstract: Background Wine aroma results from the combination of numerous volatile compounds, some produced by yeast and others produced in the grapes and further metabolized by yeast. However, little is known about the consequences of the genetic variation of yeast on the production of these volatile metabolites, or on the metabolic pathways involved in the metabolism of grape compounds. As a tool to decipher how wine aroma develops, we analyzed, under two experimental conditions, the production of 44 compounds by a population of 30 segregants from a cross between a laboratory strain and an industrial strain genotyped at high density. Results We detected eight genomic regions explaining the diversity concerning 15 compounds, some produced de novo by yeast, such as nerolidol, ethyl esters and phenyl ethanol, and others derived from grape compounds such as citronellol, and cis-rose oxide. In three of these eight regions, we identified genes involved in the phenotype. Hemizygote comparison allowed the attribution of differences in the production of nerolidol and 2-phenyl ethanol to the PDR8 and ABZ1 genes, respectively. Deletion of a PLB2 gene confirmed its involvement in the production of ethyl esters. A comparison of allelic variants of PDR8 and ABZ1 in a set of available sequences revealed that both genes present a higher than expected number of non-synonymous mutations indicating possible balancing selection. Conclusions This study illustrates the value of QTL analysis for the analysis of metabolic traits, and in particular the production of wine aromas. It also identifies the particular role of the PDR8 gene in the production of farnesyldiphosphate derivatives, of ABZ1 in the production of numerous compounds and of PLB2 in ethyl ester synthesis. This work also provides a basis for elucidating the metabolism of various grape compounds, such as citronellol and cis-rose oxide.
Saliva from Obese Individuals Suppresses the Release of Aroma Compounds from Wine  [PDF]
Paola Piombino, Alessandro Genovese, Silvia Esposito, Luigi Moio, Pier Paolo Cutolo, Angela Chambery, Valeria Severino, Elisabetta Moneta, Daniel P. Smith, Sarah M. Owens, Jack A. Gilbert, Danilo Ercolini
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0085611
Abstract: Background Recent evidence suggests that a lower extent of the retronasal aroma release correspond to a higher amount of ad libitum food intake. This has been regarded as one of the bases of behavioral choices towards food consumption in obese people. In this pilot study we investigated the hypothesis that saliva from obese individuals could be responsible for an alteration of the retro-nasal aroma release. We tested this hypothesis in vitro, by comparing the release of volatiles from a liquid food matrix (wine) after its interaction with saliva from 28 obese (O) and 28 normal-weight (N) individuals. Methods and Findings Amplicon sequencing of the 16S rRNA V4 region indicated that Firmicutes and Actinobacteria were more abundant in O, while Proteobacteria and Fusobacteria dominated in N. Streptococcaceae were significantly more abundant in the O subjects and constituted 34% and 19% on average of the saliva microbiota of O and N subjects, respectively. The Total Antioxidant Capacity was higher in O vs N saliva samples. A model mouth system was used to test whether the in-mouth wine aroma release differs after the interaction with O or N saliva. In O samples, a 18% to 60% significant decrease in the mean concentration of wine volatiles was detected as a result of interaction with saliva, compared with N. This suppression was linked to biochemical differences in O and N saliva composition, which include protein content. Conclusion Microbiological and biochemical differences were found in O vs N saliva samples. An impaired retronasal aroma release from white wine was detected in vitro and linked to compositional differences between saliva from obese and normal-weight subjects. Additional in vivo investigations on diverse food matrices could contribute to understanding whether a lower olfactory stimulation due to saliva composition can be a co-factor in the development/maintenance of obesity.
Improving the Performance of an Electronic Nose by Wine Aroma Training to Distinguish between Drip Coffee and Canned Coffee  [PDF]
Kouki Fujioka,Yasuko Tomizawa,Nobuo Shimizu,Keiichi Ikeda,Yoshinobu Manome
Sensors , 2015, DOI: 10.3390/s150101354
Abstract: Coffee aroma, with more than 600 components, is considered as one of the most complex food aromas. Although electronic noses have been successfully used for objective analysis and differentiation of total coffee aromas, it is difficult to use them to describe the specific features of coffee aroma ( i.e., the type of smell). This is because data obtained by electronic noses are generally based on electrical resistance/current and samples are distinguished by principal component analysis. In this paper, we present an electronic nose that is capable of learning the wine related aromas using the aroma kit “Le Nez du Vin,” and the potential to describe coffee aroma in a similar manner comparable to how wine experts describe wine aroma. The results of our investigation showed that the aromas of three drip coffees were more similar to those of pine and honey in the aroma kit than to the aromas of three canned coffees. Conversely, the aromas of canned coffees were more similar to the kit coffee aroma. In addition, the aromatic patterns of coffees were different from those of green tea and red wine. Although further study is required to fit the data to human olfaction, the presented method and the use of vocabularies in aroma kits promise to enhance objective discrimination and description of aromas by electronic noses.
A sensory and chemical approach to the aroma of wooden aged Lourinh? wine brandy
Caldeira,Ilda; Sousa,R. Bruno de; Belchior,A. Pedro; Clímaco,M. Cristina;
Ciência e Técnica Vitivinícola , 2008,
Abstract: the maturation of wine brandies in wooden barrels origin many sensory and physical-chemical changes in these alcoholic beverages. this work studies the odorants in different aged brandies from lourinh?. these brandies were analysed by gas chromatography coupled to olfactometry (gc-o). a panel taster profiled these brandies and the identified odorants were also quantified by gas chromatography coupled to a flame ionization detector (gc-fid). the gc-o results showed 29 identified odorants (alcohols, esters, acids and phenols). some of them are proceeding from the distillate while others are extracted from the wood. the analysis of correlation between the sensory profiles and the odorant quantification pointed out the relevance of several wood compounds for the brandy aroma, namely the vanillin, volatile phenols and furanic aldehydes. these compounds presented important correlations with several olfactory attributes like vanilla, smoke, toasted, dried fruits, woody, which influence positively the quality of the brandies.
Fungicide residues in grapes determined the dynamics of Saccharomyces cerevisiae strains during spontaneous wine fermentation  [PDF]
?u? Franc,?ade? Ne?a J.,Raspor Peter I.
Zbornik Matice Srpske za Prirodne Nauke , 2011, DOI: 10.2298/zmspn1121085c
Abstract: Impact of three fungicides against B. cinerea (iprodione, pyrimethanil and f ludioxonil plus cyprodinil) on the population of Saccharomyces cerevisiae strains during the spontaneous alcoholic fermentation was studied. With regard to the use of fungicides in the vineyard at two stages of the grapevine growth we followed four different spontaneous fermentations: control, iprodione, pyrimethanil and f ludioxonil plus cyprodinil. The fungicide residues in the grapes were determined by GC/MS system and the fermentations were followed by changes in yeast, sugar, and ethanol concentrations using colony counting and HPLC. The karyotype analysis of 473 isolates was done by pulsed-field gel electrophoresis. The fungicide residues in the grapes at the harvest were below the maximum residue limits. Isolates of S. cerevisiae were classified into 15 karyotype groups. The duration of the processes and the populations of the karyotypes differed between the fermentations. The iprodione and control fermentations lasted 36 days with the prevalence of karyotype A while the fludioxonil plus cyprodinil fermentation lasted 50 days and karyotype D led the process. In the pyrimethanil fermentation, none of the karyotypes prevailed in the must and the fermentation lasted much longer than others did (68 days). The results showed that the fungicide residues have an influence on the fermentation kinetics and selection of S. cerevisiae strains during the spontaneous alcoholic fermentation and therefore should be considered as an important factor that may indirectly influence the formation of fermentation aroma in the wine produced by such process.
Investigation of the retronasal perception of palm wine (Elaeis Guineensis) aroma by application of sensory analysis and exhaled odorant measurement (exom).
O Lasekan, A Buettner, M Christlbauer
African Journal of Food, Agriculture, Nutrition and Development , 2009,
Abstract: The headspace profile of palm wine was evaluated by time-resolved sensory analysis showing significant changes of the diverse odour attributes with time after swallowing. Fruity and citrusy were the most intense aroma qualities perceived upon sample introduction into the mouth, while swallowing of the palm wine elicited a more acidic impression followed by citrusy and fruity nuances respectively. After swallowing, panelists described an increase in the nutty and popcorn-like aroma impressions. Based on these sensory observations, the retronasal aroma perception of palm wine was investigated by application of the modified Exhaled Odorant Measurement (EXOM)-approach. In EXOM analysis, odorants that are exhaled through the nose during food consumption and swallowing are collected and analysed by high resolution gas chromatography-olfactometry and mass spectrometry, respectively. EXOM results revealed an initial 24 odor-active compounds in the \'swallow\' breath with 23 of these odorants being identified on the basis of their odor qualities and intensities, as well as chromatographic and mass spectral data. Only 14 compounds were detectable in the exhaled breath 20 s after swallowing the palm wine and 11 of these were subsequently identified. Generally, the identified odorants belonged to very diverse odorant substance classes such as heteroaromatic compounds, esters, alcohols, carbonyl and thio compounds and many more. Among these, higher persistence intervals in the exhalation breath were obtained for the buttery smelling compounds butan-2,3-dione and 3-hydroxy-butan-2-one (acetoine), 3-isobutyl 2- methoxypyrazine with bell pepper-like aroma impression, the malty smelling 2- and 3-methylbutanols, and the coconut-like smelling γ-dodecalactone. The popcorn-like smelling 2-acetyl 1-pyrroline, the fresh flowery linalool and two unknown compounds with citrusy and buttery aroma impressions were only detectable at 20 s after swallowing. Dynamic changes were also observed in retronasal sensory evaluations that were attributed to specific palm wine odorants. Accordingly, both sensory and analytical data on retronasal aroma perception of palm wine monitored the dynamic flavour changes during palm wine consumption.
Metabolic Flux Analysis during the Exponential Growth Phase of Saccharomyces cerevisiae in Wine Fermentations  [PDF]
Manuel Quirós, Rubén Martínez-Moreno, Joan Albiol, Pilar Morales, Felícitas Vázquez-Lima, Antonio Barreiro-Vázquez, Pau Ferrer, Ramon Gonzalez
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0071909
Abstract: As a consequence of the increase in global average temperature, grapes with the adequate phenolic and aromatic maturity tend to be overripe by the time of harvest, resulting in increased sugar concentrations and imbalanced C/N ratios in fermenting musts. This fact sets obvious additional hurdles in the challenge of obtaining wines with reduced alcohols levels, a new trend in consumer demands. It would therefore be interesting to understand Saccharomyces cerevisiae physiology during the fermentation of must with these altered characteristics. The present study aims to determine the distribution of metabolic fluxes during the yeast exponential growth phase, when both carbon and nitrogen sources are in excess, using continuous cultures. Two different sugar concentrations were studied under two different winemaking temperature conditions. Although consumption and production rates for key metabolites were severely affected by the different experimental conditions studied, the general distribution of fluxes in central carbon metabolism was basically conserved in all cases. It was also observed that temperature and sugar concentration exerted a higher effect on the pentose phosphate pathway and glycerol formation than on glycolysis and ethanol production. Additionally, nitrogen uptake, both quantitatively and qualitatively, was strongly influenced by environmental conditions. This work provides the most complete stoichiometric model used for Metabolic Flux Analysis of S. cerevisiae in wine fermentations employed so far, including the synthesis and release of relevant aroma compounds and could be used in the design of optimal nitrogen supplementation of wine fermentations.
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