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Sample records for wine spoilage yeast

  1. Isolation and Identification of Spoilage Yeasts in Wine Samples by MALDI-TOF MS Biotyper

    Directory of Open Access Journals (Sweden)

    Attila Kántor

    2015-05-01

    Full Text Available Many genera and species of microorganisms can be found in grape musts and wines at various times during the winemaking process. For instance, Saccharomyces, Brettanomyces, and Pediococcus can be found together in wine. There are many species of yeast involved in wine spoilage during storage. Aim of this study was to isolate the spoilage yeasts from wine samples with using special selective agar media and identified on species level by Matrix-Assisted Laser Desorption/Ionization-Time of Fly Mass Spectrometry (MALDI-TOF MS. Six red wines used in this study. We identified 10 yeast species from 152 isolates. The most common species in wine samples was Saccharomyces cerevisiae. We also identified four Candida species, two Zygosaccharomyces species and one species from genus Rhodotorula, Saccharomycodes and Dekkera.

  2. Past and Future of Non-Saccharomyces Yeasts: From Spoilage Microorganisms to Biotechnological Tools for Improving Wine Aroma Complexity

    Science.gov (United States)

    Padilla, Beatriz; Gil, José V.; Manzanares, Paloma

    2016-01-01

    It is well established that non-Saccharomyces wine yeasts, considered in the past as undesired or spoilage yeasts, can enhance the analytical composition, and aroma profile of the wine. The contribution of non-Saccharomyces yeasts, including the ability to secret enzymes and produce secondary metabolites, glycerol and ethanol, release of mannoproteins or contributions to color stability, is species- and strain-specific, pointing out the key importance of a clever strain selection. The use of mixed starters of selected non-Saccharomyces yeasts with strains of Saccharomyces cerevisiae represents an alternative to both spontaneous and inoculated wine fermentations, taking advantage of the potential positive role that non-Saccharomyces wine yeast species play in the organoleptic characteristics of wine. In this context mixed starters can meet the growing demand for new and improved wine yeast strains adapted to different types and styles of wine. With the aim of presenting old and new evidences on the potential of non-Saccharomyces yeasts to address this market trend, we mainly review the studies focused on non-Saccharomyces strain selection and design of mixed starters directed to improve primary and secondary aroma of wines. The ability of non-Saccharomyces wine yeasts to produce enzymes and metabolites of oenological relevance is also discussed. PMID:27065975

  3. Control of Native Spoilage Yeast on Dealcoholized Red Wine by Preservatives Alone and in Binary Mixtures.

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    Sánchez-Rubio, Marta; Guerrouj, Kamal; Taboada-Rodríguez, Amaury; López-Gómez, Antonio; Marín-Iniesta, Fulgencio

    2017-09-01

    In order to preserve a commercial dealcoholized red wine (DRW), a study with 4 preservatives and binary mixtures of them were performed against 2 native spoilage yeasts: Rhodotorula mucilaginosa and Saccharomyces cerevisiae. Minimal inhibitory concentration (MIC) and minimal fungicidal concentration (MFC) for potassium sorbate, sodium benzoate, sodium metabisulfite and dimethyl dicarbonate (DMDC) were evaluated in DRW stored at 25 °C. MICs of potassium sorbate and sodium metabisulfite were 250 and 60 mg/kg, respectively for both target strains. However for sodium benzoate, differences between yeasts were found; R. mucilaginosa was inhibited at 125 mg/kg, while S. cerevisiae at 250 mg/kg. Regarding MFC, differences between strains were only found for sodium metabisulfite obtaining a MFC of 500 mg/kg for R. mucilaginosa and a MFC of 250 mg/kg for S. cerevisiae. Potassium sorbate and sodium benzoate showed the MFC at 1000 mg/kg and DMDC at 200 mg/kg. Regarding the effect of binary mixtures the Fractional Fungicidal Concentration Index (FFC i ) methodology showed that binary mixtures of 100 mg/kg DMDC/200 mg/kg potassium sorbate (FFC i = 0.7) and 50 mg/kg DMDC / 400 mg/kg sodium benzoate (FFC i = 0.65) have both synergistic effect against the 2 target strains. These binary mixtures can control the growth of spoilage yeasts in DRW without metabisulfite addition. The results of this work may be important in preserving the health of DRW consumers by eliminating the use of metabisulfite and reducing the risk of growth of R. mucilagosa, recently recognized as an emerging pathogen. © 2017 Institute of Food Technologists®.

  4. Growth inhibitory effect of grape phenolics against wine spoilage yeasts and acetic acid bacteria

    Czech Academy of Sciences Publication Activity Database

    Pastorková, E.; Žáková, T.; Landa, Přemysl; Nováková, J.; Vadlejch, J.; Kokoška, L.

    2013-01-01

    Roč. 161, č. 3 (2013), s. 209-213 ISSN 0168-1605 R&D Projects: GA MŠk(CZ) LD11005 Institutional research plan: CEZ:AV0Z50380511 Keywords : Phenolic compound * Antimicrobial activity * Wine spoilage microorganism Subject RIV: GM - Food Processing Impact factor: 3.155, year: 2013

  5. Heat inactivation of wine spoilage yeast Dekkera bruxellensis by hot water treatment.

    Science.gov (United States)

    Fabrizio, V; Vigentini, I; Parisi, N; Picozzi, C; Compagno, C; Foschino, R

    2015-08-01

    Cell suspensions of four Dekkera bruxellensis strains (CBS 2499, CBS 2797, CBS 4459 and CBS 4601) were subjected to heat treatment in deionized water at four different temperatures (55·0, 57·5, 60·0 and 62·5°C) to investigate their thermal resistance. The decimal reduction times at a specific temperature were calculated from the resulting inactivation curves: the D-values at 55·0°C ranged from 63 to 79·4 s, at 57·5°C from 39·6 to 46·1 s, at 60·0°C from 19·5 to 20·7 s, at 62·5°C from 10·2 to 13·7 s. The z-values were between 9·2 and 10·2°C, confirming that heat resistance is a strain-dependent character. A protocol for the sanitization of 225 l casks by immersion in hot water was set up and applied to contaminated 3-year-old barrels. The heat penetration through the staves was evaluated for each investigated temperature by positioning a thermal probe at 8 mm deep. A treatment at 60°C for an exposure time of 19 min allowed to eliminate the yeast populations up to a log count reduction of 8. Brettanomyces/Dekkera bruxellensis is the main yeast involved in red wine spoilage that occurs during ageing in barrel, generating considerable economic losses. Current sanitization protocols, performed using different chemicals, are ineffective due to the porous nature of the wood. The thermal inactivation of D. bruxellensis cells by hot water treatment proves to be efficacious and easy to perform, provided that the holding time at the killing temperature takes into account the filling time of the vessel and the time for the heat penetration into the wood structure. © 2015 The Society for Applied Microbiology.

  6. The carbon consumption pattern of the spoilage yeast Brettanomyces bruxellensis in synthetic wine-like medium.

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    Smith, Brendan D; Divol, Benoit

    2018-08-01

    The wine matrix contains limited carbon compounds to sustain microbial life. Brettanomyces bruxellensis is one of very few yeast species that has adapted to this environment. Indeed, the presence of growth-inhibiting compounds and conditions do not prevent its proliferation. Literature regarding the nutritional requirements of this yeast is surprisingly poor, given the observation that B. bruxellensis produces biomass with apparently less nutrients than other yeasts. In this study, various carbon sources were screened in a synthetic wine medium, under anaerobic and semi-aerobic growth conditions, in order to determine which compounds B. bruxellensis assimilates. Slight differences were observed between strains but overall, B. bruxellensis produced biomass from limited nutrients consumed in a specific order regardless of the oxygen conditions. Upon initial consumption of the simple sugars, B. bruxellensis was able to remain viable, by concurrently utilising ethanol (only in the presence of oxygen) and malic acid. Although initially beneficial, oxygen was found detrimental in the long term. Formation of volatile phenols occurred during the consumption of the sugars but not as a mechanism to help correct the redox imbalance. The study confirms that B. bruxellensis is able to survive using limited amount of nutrients, making this yeast a challenge for winemakers. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. A differential medium for the enumeration of the spoilage yeast Zygosaccharomyces bailii in wine.

    Science.gov (United States)

    Schuller, D; Côrte-Real, M; Leão, C

    2000-11-01

    A collection of yeasts, isolated mostly from spoiled wines, was used in order to develop a differential medium for Zygosaccharomyces bailii. The 118 selected strains of 21 species differed in their origin and resistance to preservatives and belonged to the genera Pichia, Torulaspora, Dekkera, Debaryomyces, Saccharomycodes, Issatchenkia, Kluyveromyces, Kloeckera, Lodderomyces, Schizosaccharomyces, Rhodotorula, Saccharomyces, and Zygosaccharomyces. The design of the culture medium was based on the different ability of the various yeast species to grow in a mineral medium with glucose and formic acid (mixed-substrate medium) as the only carbon and energy sources and supplemented with an acid-base indicator. By manipulating the concentration of the acid and the sugar it was possible to select conditions where only Z. bailii strains gave rise to alkalinization, associated with a color change of the medium (positive response). The final composition of the mixed medium was adjusted as a compromise between the percentage of recovery and selectivity for Z. bailii. This was accomplished by the use of pure or mixed cultures of the yeast strains and applying the membrane filtration methodology. The microbiological analysis of two samples of contaminated Vinho Verde showed that the new medium can be considered as a differential medium to distinguish Z. bailii from other contaminating yeasts, having potential application in the microbiological control of wines and probably other beverages and foods.

  8. Outlining a future for non-Saccharomyces yeasts: selection of putative spoilage wine strains to be used in association with Saccharomyces cerevisiae for grape juice fermentation.

    Science.gov (United States)

    Domizio, Paola; Romani, Cristina; Lencioni, Livio; Comitini, Francesca; Gobbi, Mirko; Mannazzu, Ilaria; Ciani, Maurizio

    2011-06-30

    The use of non-Saccharomyces yeasts that are generally considered as spoilage yeasts, in association with Saccharomyces cerevisiae for grape must fermentation was here evaluated. Analysis of the main oenological characteristics of pure cultures of 55 yeasts belonging to the genera Hanseniaspora, Pichia, Saccharomycodes and Zygosaccharomyces revealed wide biodiversity within each genus. Moreover, many of these non-Saccharomyces strains had interesting oenological properties in terms of fermentation purity, and ethanol and secondary metabolite production. The use of four non-Saccharomyces yeasts (one per genus) in mixed cultures with a commercial S. cerevisiae strain at different S. cerevisiae/non-Saccharomyces inoculum ratios was investigated. This revealed that most of the compounds normally produced at high concentrations by pure cultures of non-Saccharomyces, and which are considered detrimental to wine quality, do not reach threshold taste levels in these mixed fermentations. On the other hand, the analytical profiles of the wines produced by these mixed cultures indicated that depending on the yeast species and the S. cerevisiae/non-Saccharomyces inoculum ratio, these non-Saccharomyces yeasts can be used to increase production of polysaccharides and to modulate the final concentrations of acetic acid and volatile compounds, such as ethyl acetate, phenyl-ethyl acetate, 2-phenyl ethanol, and 2-methyl 1-butanol. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Probabilistic model for the spoilage wine yeast Dekkera bruxellensis as a function of pH, ethanol and free SO2 using time as a dummy variable.

    Science.gov (United States)

    Sturm, M E; Arroyo-López, F N; Garrido-Fernández, A; Querol, A; Mercado, L A; Ramirez, M L; Combina, M

    2014-01-17

    The present study uses a probabilistic model to determine the growth/no growth interfaces of the spoilage wine yeast Dekkera bruxellensis CH29 as a function of ethanol (10-15%, v/v), pH (3.4-4.0) and free SO2 (0-50 mg/l) using time (7, 14, 21 and 30 days) as a dummy variable. The model, built with a total of 756 growth/no growth data obtained in a simile wine medium, could have application in the winery industry to determine the wine conditions needed to inhibit the growth of this species. Thereby, at 12.5% of ethanol and pH 3.7 for a growth probability of 0.01, it is necessary to add 30 mg/l of free SO2 to inhibit yeast growth for 7 days. However, the concentration of free SO2 should be raised to 48 mg/l to achieve a probability of no growth of 0.99 for 30 days under the same wine conditions. Other combinations of environmental variables can also be determined using the mathematical model depending on the needs of the industry. Copyright © 2013 Elsevier B.V. All rights reserved.

  10. Spoilage potential of brettanomyces bruxellensis strains isolated from Italian wines.

    Science.gov (United States)

    Guzzon, Raffaele; Larcher, Roberto; Guarcello, Rosa; Francesca, Nicola; Settanni, Luca; Moschetti, Giancarlo

    2018-03-01

    Brettanomyces bruxellensis is an important wine spoilage agent. In this study a population of Brettanomyces strains isolated from Italian wines was thoroughly investigated to evaluate adaptability to wine conditions and spoilage potential. The presumptive isolates of Brettanomyces were identified at species level with 26S rRNA gene sequencing and species-specific PCR, and subsequently subjected to analysis of intra-species variability through the study of intron splice sites (ISS-PCR). Although, some strains were tracked in wines from different regions, extensive genetic biodiversity was observed within the B. bruxellensis population investigated. All strains were evaluated for their growth ability in the presence of ethanol, high sugar content, low pH, different temperatures and sulphur dioxide, using optical density and flow cytometry measurement. The ability of yeasts to produce ethyl phenols in red wines with different chemical compositions was evaluated by means of high performance liquid chromatography with electrochemical detection (HPLC-ECD). The results highlighted wide variability in B. bruxellensis in response to wine limiting factors and in terms of the accumulation of ethyl phenols. As regards this last aspect, the differences found among strains were closely related to chemical composition of wine and strain resistance to environmental stress factors, making a priori evaluation of risk of wine alteration quite difficult. These results suggest that strategies for the control of Brettanomyces should be tailored on the basis of strain distribution and wine characteristics. Copyright © 2017. Published by Elsevier Ltd.

  11. Brettanomyces bruxellensis yeasts: impact on wine and winemaking.

    Science.gov (United States)

    Agnolucci, Monica; Tirelli, Antonio; Cocolin, Luca; Toffanin, Annita

    2017-09-21

    Yeasts belonging to the Brettanomyces/Dekkera genus are non-conventional yeasts, which affect winemaking by causing wine spoilage all over the world. This mini-review focuses on recent results concerning the presence of Brettanomyces bruxellensis throughout the wine processing chain. Here, culture-dependent and independent methods to detect this yeast on grapes and at the very early stage of wine production are encompassed. Chemical, physical and biological tools, devised for the prevention and control of such a detrimental species during winemaking are also presented. Finally, the mini-review identifies future research areas relevant to the improvement of wine safety and sensory profiles.

  12. The wine and beer yeast Dekkera bruxellensis.

    Science.gov (United States)

    Schifferdecker, Anna Judith; Dashko, Sofia; Ishchuk, Olena P; Piškur, Jure

    2014-09-01

    Recently, the non-conventional yeast Dekkera bruxellensis has been gaining more and more attention in the food industry and academic research. This yeast species is a distant relative of Saccharomyces cerevisiae and is especially known for two important characteristics: on the one hand, it is considered to be one of the main spoilage organisms in the wine and bioethanol industry; on the other hand, it is 'indispensable' as a contributor to the flavour profile of Belgium lambic and gueuze beers. Additionally, it adds to the characteristic aromatic properties of some red wines. Recently this yeast has also become a model for the study of yeast evolution. In this review we focus on the recently developed molecular and genetic tools, such as complete genome sequencing and transformation, to study and manipulate this yeast. We also focus on the areas that are particularly well explored in this yeast, such as the synthesis of off-flavours, yeast detection methods, carbon metabolism and evolutionary history. © 2014 The Authors. Yeast published by John Wiley & Sons, Ltd.

  13. Analysis of Growth Inhibition and Metabolism of Hydroxycinnamic Acids by Brewing and Spoilage Strains of Brettanomyces Yeast

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    Michael Lentz

    2015-10-01

    Full Text Available Brettanomyces yeasts are well-known as spoilage organisms in both the wine and beer industries, but also contribute important desirable characters to certain beer styles. These properties are mediated in large part by Brettanomyces’ metabolism of hydroxycinnamic acids (HCAs present in beverage raw materials. Here we compare growth inhibition by, and metabolism of, HCAs among commercial brewing strains and spoilage strains of B. bruxellensis and B. anomalus. These properties vary widely among the different strains tested and between the HCAs analyzed. Brewing strains showed more efficient metabolism of ferulic acid over p-coumaric acid, a trait not shared among the spoilage strains.

  14. Analysis of Growth Inhibition and Metabolism of Hydroxycinnamic Acids by Brewing and Spoilage Strains of Brettanomyces Yeast.

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    Lentz, Michael; Harris, Chad

    2015-10-15

    Brettanomyces yeasts are well-known as spoilage organisms in both the wine and beer industries, but also contribute important desirable characters to certain beer styles. These properties are mediated in large part by Brettanomyces ' metabolism of hydroxycinnamic acids (HCAs) present in beverage raw materials. Here we compare growth inhibition by, and metabolism of, HCAs among commercial brewing strains and spoilage strains of B. bruxellensis and B. anomalus . These properties vary widely among the different strains tested and between the HCAs analyzed. Brewing strains showed more efficient metabolism of ferulic acid over p -coumaric acid, a trait not shared among the spoilage strains.

  15. Determination of tritium in wine yeast samples

    International Nuclear Information System (INIS)

    Cotarlea, Monica-Ionela; Paunescu Niculina; Galeriu, D; Mocanu, N.; Margineanu, R.; Marin, G.

    1998-01-01

    Analytical procedures were developed to determine tritium in wine and wine yeast samples. The content of organic compounds affecting the LSC measurement is reduced by fractioning distillation for wine samples and azeotropic distillation/fractional distillation for wine yeast samples. Finally, the water samples were normally distilled with K MO 4 . The established procedures were successfully applied for wine and wine samples from Murfatlar harvests of the years 1995 and 1996. (authors)

  16. Potential spoilage yeasts in winery environments: Characterization and proteomic analysis of Trigonopsis cantarellii.

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    Portugal, Cauré; Pinto, Luís; Ribeiro, Miguel; Tenorio, Carmen; Igrejas, Gilberto; Ruiz-Larrea, Fernanda

    2015-10-01

    Wine microbiota is complex and includes a wide diversity of yeast species. Few of them are able to survive under the restrictive conditions of dry red wines. In our study we detected and identified seven yeast species of the order Saccharomycetales that can be considered potential spoilers of wines due to physiological traits such as acidogenic metabolism and off-odor generation: Arthroascus schoenii, Candida ishiwadae, Meyerozyma guilliermondii, Pichia holstii, Pichia manshurica, Trigonopsis cantarellii, and Trigonopsis variabilis. Based on the prevalence of T. cantarellii isolates in the wine samples of our study, we further characterized this species, determined molecular and phenotypic features, and performed a proteomic analysis to identify differentially expressed proteins at mid-exponential growth phase in the presence of ethanol in the culture broth. This yeast species is shown to be able to grow in the presence of ethanol by expressing heat shock proteins (Hsp70, Hsp71) and a DNA damage-related protein (Rad24), and to be able to confer spoilage characteristics on wine. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Determination of tritium in wine and wine yeast samples

    International Nuclear Information System (INIS)

    Cotarlea, Monica-Ionela; Paunescu, Niculina; Galeriu, D.; Mocanu, N.; Margineanu, R.; Marin, G.

    1997-01-01

    A sensitive method for evaluating the tritium content in wine and wine yeast was applied to estimate tritium impact on the environment in the surrounding area of nuclear power plant Cernavoda, where the vineyards are part of representative agricultural ecosystem. Analytical procedures were developed to determine HTO in wine and wine yeast samples. The content of organic compounds affecting the LSC measurement is reduced by fractionating distillation for wine samples and azeotropic distillation followed by fractional distillation for wine yeast samples. Finally, the water samples obtained after fractional distillation were normally distilled with KMO 4 . The established procedures were successfully applied for wine and wine yeast samples from Mulfatlar harvests of the years 1995 and 1996. (authors)

  18. Not your ordinary yeast: non-Saccharomyces yeasts in wine production uncovered.

    Science.gov (United States)

    Jolly, Neil P; Varela, Cristian; Pretorius, Isak S

    2014-03-01

    Saccharomyces cerevisiae and grape juice are 'natural companions' and make a happy wine marriage. However, this relationship can be enriched by allowing 'wild' non-Saccharomyces yeast to participate in a sequential manner in the early phases of grape must fermentation. However, such a triangular relationship is complex and can only be taken to 'the next level' if there are no spoilage yeast present and if the 'wine yeast' - S. cerevisiae - is able to exert its dominance in time to successfully complete the alcoholic fermentation. Winemakers apply various 'matchmaking' strategies (e.g. cellar hygiene, pH, SO2 , temperature and nutrient management) to keep 'spoilers' (e.g. Dekkera bruxellensis) at bay, and allow 'compatible' wild yeast (e.g. Torulaspora delbrueckii, Pichia kluyveri, Lachancea thermotolerans and Candida/Metschnikowia pulcherrima) to harmonize with potent S. cerevisiae wine yeast and bring the best out in wine. Mismatching can lead to a 'two is company, three is a crowd' scenario. More than 40 of the 1500 known yeast species have been isolated from grape must. In this article, we review the specific flavour-active characteristics of those non-Saccharomyces species that might play a positive role in both spontaneous and inoculated wine ferments. We seek to present 'single-species' and 'multi-species' ferments in a new light and a new context, and we raise important questions about the direction of mixed-fermentation research to address market trends regarding so-called 'natural' wines. This review also highlights that, despite the fact that most frontier research and technological developments are often focussed primarily on S. cerevisiae, non-Saccharomyces research can benefit from the techniques and knowledge developed by research on the former. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  19. Flor Yeast: New Perspectives Beyond Wine Aging

    Science.gov (United States)

    Legras, Jean-Luc; Moreno-Garcia, Jaime; Zara, Severino; Zara, Giacomo; Garcia-Martinez, Teresa; Mauricio, Juan C.; Mannazzu, Ilaria; Coi, Anna L.; Bou Zeidan, Marc; Dequin, Sylvie; Moreno, Juan; Budroni, Marilena

    2016-01-01

    The most important dogma in white-wine production is the preservation of the wine aroma and the limitation of the oxidative action of oxygen. In contrast, the aging of Sherry and Sherry-like wines is an aerobic process that depends on the oxidative activity of flor strains of Saccharomyces cerevisiae. Under depletion of nitrogen and fermentable carbon sources, these yeast produce aggregates of floating cells and form an air–liquid biofilm on the wine surface, which is also known as velum or flor. This behavior is due to genetic and metabolic peculiarities that differentiate flor yeast from other wine yeast. This review will focus first on the most updated data obtained through the analysis of flor yeast with -omic tools. Comparative genomics, proteomics, and metabolomics of flor and wine yeast strains are shedding new light on several features of these special yeast, and in particular, they have revealed the extent of proteome remodeling imposed by the biofilm life-style. Finally, new insights in terms of promotion and inhibition of biofilm formation through small molecules, amino acids, and di/tri-peptides, and novel possibilities for the exploitation of biofilm immobilization within a fungal hyphae framework, will be discussed. PMID:27148192

  20. Occurrence and growth of yeasts in processed meat products - implications for potential spoilage

    DEFF Research Database (Denmark)

    Nielsen, Dennis Sandris; Jacobsen, Tomas; Jespersen, Lene

    2008-01-01

    of the processed meat products. The yeast microflora was complex with 4-12 different species isolated from the different production sites. In general, Candida zeylanoides, Debaryomyces hansenii and the newly described Candida alimentaria were found to be the dominant yeast species. In addition, three putatively......Spoilage of meat products is in general attributed to bacteria but new processing and storage techniques inhibiting growth of bacteria may provide opportunities for yeasts to dominate the microflora and cause spoilage of the product. With the aim of obtaining a deeper understanding of the potential...... role of yeast in spoilage of five different processed meat products (bacon, ham, salami and two different liver patés), yeasts were isolated, enumerated and identified during processing, in the final product and in the final product at the end of shelf life. Yeasts were isolated along the bacon...

  1. The fate of acetic acid during glucose co-metabolism by the spoilage yeast Zygosaccharomyces bailii.

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    Fernando Rodrigues

    Full Text Available Zygosaccharomyces bailii is one of the most widely represented spoilage yeast species, being able to metabolise acetic acid in the presence of glucose. To clarify whether simultaneous utilisation of the two substrates affects growth efficiency, we examined growth in single- and mixed-substrate cultures with glucose and acetic acid. Our findings indicate that the biomass yield in the first phase of growth is the result of the weighted sum of the respective biomass yields on single-substrate medium, supporting the conclusion that biomass yield on each substrate is not affected by the presence of the other at pH 3.0 and 5.0, at least for the substrate concentrations examined. In vivo(13C-NMR spectroscopy studies showed that the gluconeogenic pathway is not operational and that [2-(13C]acetate is metabolised via the Krebs cycle leading to the production of glutamate labelled on C(2, C(3 and C(4. The incorporation of [U-(14C]acetate in the cellular constituents resulted mainly in the labelling of the protein and lipid pools 51.5% and 31.5%, respectively. Overall, our data establish that glucose is metabolised primarily through the glycolytic pathway, and acetic acid is used as an additional source of acetyl-CoA both for lipid synthesis and the Krebs cycle. This study provides useful clues for the design of new strategies aimed at overcoming yeast spoilage in acidic, sugar-containing food environments. Moreover, the elucidation of the molecular basis underlying the resistance phenotype of Z. bailii to acetic acid will have a potential impact on the improvement of the performance of S. cerevisiae industrial strains often exposed to acetic acid stress conditions, such as in wine and bioethanol production.

  2. Hybridization of Palm Wine Yeasts ( Saccharomyces Cerevisiae ...

    African Journals Online (AJOL)

    Haploid auxotrophic strains of Saccharomyces cerevisiae were selected from palm wine and propagated by protoplast fusion with Brewers yeast. Fusion resulted in an increase in both ethanol production and tolerance against exogenous ethanol. Mean fusion frequencies obtained for a mating types ranged between 8 x ...

  3. [Application of Fourier transform infrared spectroscopy in identification of wine spoilage].

    Science.gov (United States)

    Zhao, Xian-De; Dong, Da-Ming; Zheng, Wen-Gang; Jiao, Lei-Zi; Lang, Yun

    2014-10-01

    In the present work, fresh and spoiled wine samples from three wines produced by different companies were studied u- sing Fourier transform infrared (FTIR) spectroscopy. We analyzed the physicochemical property change in the process of spoil- age, and then, gave out the attribution of some main FTIR absorption peaks. A novel determination method was explored based on the comparisons of some absorbance ratios at different wavebands although the absorbance ratios in this method were relative. Through the compare of the wine spectra before and after spoiled, the authors found that they were informative at the bands of 3,020~2,790, 1,760~1,620 and 1,550~800 cm(-1). In order to find the relation between these informative spectral bands and the wine deterioration and achieve the discriminant analysis, chemometrics methods were introduced. Principal compounds analysis (PCA) and soft independent modeling of class analogy (SIMCA) were used for classifying different-quality wines. And partial least squares discriminant analysis (PLS-DA) was applied to identify spoiled wines and good wines. Results showed that FTIR technique combined with chemometrics methods could effectively distinguish spoiled wines from fresh samples. The effect of classification at the wave band of 1 550-800 cm(-1) was the best. The recognition rate of SIMCA and PLSDA were respectively 94% and 100%. This study demonstrates that Fourier transform infrared spectroscopy is an effective tool for monitoring red wine's spoilage and provides theoretical support for developing early-warning equipments.

  4. Biological Demalication and Deacetification of Musts and Wines: Can Wine Yeasts Make the Wine Taste Better?

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    Alice Vilela

    2017-10-01

    Full Text Available Grape musts sometimes reveal excess acidity. An excessive amount of organic acids negatively affect wine yeasts and yeast fermentation, and the obtained wines are characterized by an inappropriate balance between sweetness, acidity or sourness, and flavor/aroma components. An appropriate acidity, pleasant to the palate is more difficult to achieve in wines that have high acidity due to an excess of malic acid, because the Saccharomyces species in general, cannot effectively degrade malic acid during alcoholic fermentation. One approach to solving this problem is biological deacidification by lactic acid bacteria or non-Saccharomyces yeasts, like Schizosaccharomyces pombe that show the ability to degrade L-malic acid. Excessive volatile acidity in wine is also a problem in the wine industry. The use of free or immobilized Saccharomyces cells has been studied to solve both these problems since these yeasts are wine yeasts that show a good balance between taste/flavor and aromatic compounds during alcoholic fermentation. The aim of this review is to give some insights into the use of Saccharomyces cerevisiae strains to perform biological demalication (malic acid degradation and deacetification (reduction of volatile acidity of wine in an attempt to better understand their biochemistry and enological features.

  5. Stress tolerance in fungi - to kill a spoilage yeast.

    NARCIS (Netherlands)

    Smits, G.J.; Brul, S.

    2005-01-01

    The fungal spoilage of ingredients of food manufacture is an economic problem, often causes product loss and may constitute a health hazard. To effectively combat fungal food spoilage, a mechanistic understanding of tolerance for, and adaptation to, the preservation method used is crucial. Both are

  6. Introducing a new breed of wine yeast: interspecific hybridisation between a commercial Saccharomyces cerevisiae wine yeast and Saccharomyces mikatae.

    Science.gov (United States)

    Bellon, Jennifer R; Schmid, Frank; Capone, Dimitra L; Dunn, Barbara L; Chambers, Paul J

    2013-01-01

    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.

  7. Introducing a new breed of wine yeast: interspecific hybridisation between a commercial Saccharomyces cerevisiae wine yeast and Saccharomyces mikatae.

    Directory of Open Access Journals (Sweden)

    Jennifer R Bellon

    Full Text Available 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.

  8. Introducing a New Breed of Wine Yeast: Interspecific Hybridisation between a Commercial Saccharomyces cerevisiae Wine Yeast and Saccharomyces mikatae

    Science.gov (United States)

    Bellon, Jennifer R.; Schmid, Frank; Capone, Dimitra L.; Dunn, Barbara L.; Chambers, Paul J.

    2013-01-01

    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. PMID:23614011

  9. Characterization of wine yeasts for ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Jimenez, J.; Benitez, T.

    1986-11-01

    Selected wine yeasts were tested for their ethanol and sugar tolerance, and for their fermentative capacity. Growth (..mu..) and fermentation rates (..nu..) were increasingly inhibited by increasing ethanol and glucose concentrations, ''flor'' yeasts being the least inhibited. Except in the latter strains, the ethanol production rate was accelerated by adding the glucose stepwise. The best fermenting strains selected in laboratory medium were also the best at fermenting molasses. Invertase activity was not a limiting step in ethanol production, ..nu.. being accelerated by supplementing molasses with ammonia and biotine, and by cell recycle.

  10. Properties of palm wine yeasts and its performance in wine making ...

    African Journals Online (AJOL)

    Fresh palm wine samples were obtained from oil palm and raffia palm into sterile flasks. The samples were examined for yeasts properties and performance in wine making using grapes. The yeasts in the palm wine were characterized, identified, and screened for their sedimentation rate, ethanol tolerance, alcohol content, ...

  11. Molecular comparisons for identification of food spoilage yeasts and prediction of species that may develop in different food products

    Science.gov (United States)

    Spoilage of foods and beverages by yeasts is often characterized by objectionable odors, appearance, taste, texture or build-up of gas in packaging containers, resulting in loss of the product. Seldom is human health compromised by products spoiled by yeasts even though some spoilage is caused by sp...

  12. The occurrence of spoilage yeasts in cream-filled bakery products.

    Science.gov (United States)

    Osimani, Andrea; Milanović, Vesna; Taccari, Manuela; Cardinali, Federica; Pasquini, Marina; Aquilanti, Lucia; Clementi, Francesca

    2017-04-01

    Filling creams can provide an adequate substrate for spoilage yeasts because some yeasts can tolerate the high osmotic stress in these products. To discover the source of spoilage of a cream-filled baked product, end products, raw materials, indoor air and work surfaces were subjected to microbiological and molecular analyses. The efficacy of disinfectants against spoilage yeasts was also assessed. The analyses on end products revealed the presence of the closest relatives to Zygosaccharomyces bailii with counts ranging from 1.40 to 4.72 log cfu g -1 . No spoilage yeasts were found in the indoor air and work surfaces. Polymerase chain reaction-denaturing gradient gel electrophoresis analysis, carried out directly on filling creams collected from unopened cans, showed the presence of bands ascribed to the closest relatives to Z. bailii sensu lato, although with counts products, reliable and sensitive methods must be used. Moreover, hygiene and the application of good manufacturing practices represent the most efficient way for the prevention and minimization of cross-contamination. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  13. Yeast cell wall chitin reduces wine haze formation.

    Science.gov (United States)

    Ndlovu, Thulile; Divol, Benoit; Bauer, Florian F

    2018-04-27

    Protein haze formation in bottled wines is a significant concern for the global wine industry and wine clarification before bottling is therefore a common but expensive practice. Previous studies have shown that wine yeast strains can reduce haze formation through the secretion of certain mannoproteins, but it has been suggested that other yeast-dependent haze protective mechanisms exist. On the other hand, addition of chitin has been shown to reduce haze formation, likely because grape chitinases have been shown to be the major contributors to haze. In this study, Chardonnay grape must fermented by various yeast strains resulted in wines with different protein haze levels indicating differences in haze protective capacities of the strains. The cell wall chitin levels of these strains were determined, and a strong correlation between cell wall chitin levels and haze protection capability was observed. To further evaluate the mechanism of haze protection, Escherichia coli -produced GFP-tagged grape chitinase was shown to bind efficiently to yeast cell walls in a cell wall chitin concentration-dependent manner, while commercial chitinase was removed from synthetic wine in quantities also correlated with the cell wall chitin levels of the strains. Our findings suggest a new mechanism of reducing wine haze, and propose a strategy for optimizing wine yeast strains to improve wine clarification. Importance In this study, we establish a new mechanism by which wine yeast strains can impact on the protein haze formation of wines, and demonstrate that yeast cell wall chitin binds grape chitinase in a chitin-concentration dependent manner. We also show that yeast can remove this haze-forming protein from wine. Chitin has in the past been shown to efficiently reduce wine haze formation when added to the wine in high concentration as a clarifying agent. Our data suggest that the selection of yeast strains with high levels of cell wall chitin can reduce protein haze. We also

  14. Newly generated interspecific wine yeast hybrids introduce flavour and aroma diversity to wines.

    Science.gov (United States)

    Bellon, Jennifer R; Eglinton, Jeffery M; Siebert, Tracey E; Pollnitz, Alan P; Rose, Louisa; de Barros Lopes, Miguel; Chambers, Paul J

    2011-08-01

    Increasingly, winemakers are looking for ways to introduce aroma and flavour diversity to their wines as a means of improving style and increasing product differentiation. While currently available commercial yeast strains produce consistently sound fermentations, there are indications that sensory complexity and improved palate structure are obtained when other species of yeast are active during fermentation. In this study, we explore a strategy to increase the impact of non-Saccharomyces cerevisiae inputs without the risks associated with spontaneous fermentations, through generating interspecific hybrids between a S. cerevisiae wine strain and a second species. For our experiments, we used rare mating to produce hybrids between S. cerevisiae and other closely related yeast of the Saccharomyces sensu stricto complex. These hybrid yeast strains display desirable properties of both parents and produce wines with concentrations of aromatic fermentation products that are different to what is found in wine made using the commercial wine yeast parent. Our results demonstrate, for the first time, that the introduction of genetic material from a non-S. cerevisiae parent into a wine yeast background can impact favourably on the wine flavour and aroma profile of a commercial S. cerevisiae wine yeast.

  15. Yeast species associated with wine grapes in China.

    Science.gov (United States)

    Li, Shuang-Shi; Cheng, Chao; Li, Zheng; Chen, Jing-Yu; Yan, Bin; Han, Bei-Zhong; Reeves, Malcolm

    2010-03-31

    Having more information on the yeast ecology of grapes is important for wine-makers to produce wine with high quality and typical attributes. China is a significant wine-consuming country and is becoming a serious wine-producer, but little has been reported about the yeast ecology of local ecosystems. This study provides the first step towards the exploitation of the yeast wealth in China's vine-growing regions. The aim of this study was to investigate the yeast population density and diversity on three grape varieties cultivated in four representative vine-growing regions of China. Yeast species diversity was evaluated by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and sequence analysis of the 5.8S internal transcribed spacer (ITS) ribosomal DNA (rDNA) region of cultivable yeasts. The grapes harbored yeast populations at 10(2)-10(6)CFU/mL, consisting mostly of non-Saccharomyces species. Seventeen different yeast species belonging to eight genera were detected on the grape samples tested, including Hanseniaspora uvarum, Cryptococcus flavescens, Pichia fermentans, Candida zemplinina, Cryptococcus carnescens, Candida inconpicua, Zygosaccharomyces fermentati, Issatchenkia terricola, Candida quercitrusa, Hanseniaspora guilliermondii, Candida bombi, Zygosaccharomyces bailii, Sporidiobolus pararoseus, Cryptococcus magnus, Metschnikowia pulcherrima, Issatchenkia orientalis and Pichia guilliermondii. H. uvarum and C. flavescens were the dominant species present on the grapes. For the first time Sporidiobolus pararoseus was discovered as an inhabitant of the grape ecosystem. The yeast community on grape berries was influenced by the grape chemical composition, vine-variety and vine-growing region. This study is the first to identify the yeast communities associated with grapes in China using molecular methods. The results enrich our knowledge of wine-related microorganisms, and can be used to promote the development of the local wine

  16. Diversity and adaptive evolution of Saccharomyces wine yeast: a review

    Science.gov (United States)

    Marsit, Souhir; Dequin, Sylvie

    2015-01-01

    Saccharomyces cerevisiae and related species, the main workhorses of wine fermentation, have been exposed to stressful conditions for millennia, potentially resulting in adaptive differentiation. As a result, wine yeasts have recently attracted considerable interest for studying the evolutionary effects of domestication. The widespread use of whole-genome sequencing during the last decade has provided new insights into the biodiversity, population structure, phylogeography and evolutionary history of wine yeasts. Comparisons between S. cerevisiae isolates from various origins have indicated that a variety of mechanisms, including heterozygosity, nucleotide and structural variations, introgressions, horizontal gene transfer and hybridization, contribute to the genetic and phenotypic diversity of S. cerevisiae. This review will summarize the current knowledge on the diversity and evolutionary history of wine yeasts, focusing on the domestication fingerprints identified in these strains. PMID:26205244

  17. A new methodology to obtain wine yeast strains overproducing mannoproteins.

    Science.gov (United States)

    Quirós, Manuel; Gonzalez-Ramos, Daniel; Tabera, Laura; Gonzalez, Ramon

    2010-04-30

    Yeast mannoproteins are highly glycosylated proteins that are covalently bound to the beta-1,3-glucan present in the yeast cell wall. Among their outstanding enological properties, yeast mannoproteins contribute to several aspects of wine quality by protecting against protein haze, reducing astringency, retaining aroma compounds and stimulating growth of lactic-acid bacteria. The development of a non-recombinant method to obtain enological yeast strains overproducing mannoproteins would therefore be very useful. Our previous experience on the genetic determinants of the release of these molecules by Saccharomyces cerevisiae has allowed us to propose a new methodology to isolate and characterize wine yeast that overproduce mannoproteins. The described methodology is based on the resistance of the killer 9 toxin produced by Williopsis saturnus, a feature linked to an altered biogenesis of the yeast cell wall. Copyright 2010 Elsevier B.V. All rights reserved.

  18. Effects of a spoilage yeast from silage on in vitro ruminal fermentation.

    Science.gov (United States)

    Santos, M C; Lock, A L; Mechor, G D; Kung, L

    2015-04-01

    Feeding silages with high concentrations of yeasts from aerobic spoilage is often implicated as a cause of poor animal performance on dairies. Our objective was to determine if a commonly found spoilage yeast, isolated from silage, had the potential to alter in vitro ruminal fermentations. A single colony of Issatchenkia orientalis, isolated from high-moisture corn, was grown in selective medium. The yeast culture was purified and added to in vitro culture tubes containing a total mixed ration (43% concentrate, 43% corn silage, 11% alfalfa haylage, and 3% alfalfa hay on a dry matter basis), buffer, and ruminal fluid to achieve added theoretical final concentrations of 0 (CTR), 4.40 (low yeast; LY), 6.40 (medium yeast; MY), and 8.40 (high yeast; HY) log10 cfu of yeast/mL of in vitro fluid. Seven separate tubes were prepared for each treatment and each time point and incubated for 12 and 24h at 39 °C. At the end of the incubation period, samples were analyzed for pH, yeast number, neutral detergent fiber (NDF) digestibility, volatile fatty acids (VFA), and fatty acids (FA). We found that total viable yeast counts decreased for all treatments in in vitro incubations but were still relatively high (5.3 log10 cfu of yeasts/mL) for HY after 24h of incubation. Addition of HY resulted in a lower pH and higher concentration of total VFA in culture fluid compared with other treatments. Moreover, additions of MY and HY decreased in vitro NDF digestibility compared with CTR, and the effect was greatest for HY. Overall, the biohydrogenation of dietary unsaturated FA was not altered by addition of I. orientalis and decreased over time with an increase in the accumulation of saturated FA, especially palmitic and stearic acids. We conclude that addition of I. orientalis, especially at high levels, has the potential to reduce in vitro NDF digestion and alter other aspects of ruminal fermentations. Copyright © 2015 American Dairy Science Association. Published by Elsevier Inc. All

  19. Characterization of specialized flocculent yeasts to improve sparkling wine fermentation.

    Science.gov (United States)

    Tofalo, R; Perpetuini, G; Di Gianvito, P; Arfelli, G; Schirone, M; Corsetti, A; Suzzi, G

    2016-06-01

    Flocculent wine yeasts were characterized for the expression of FLO1, FLO5, FLO8, AMN1 and RGA1 genes, growth kinetics and physicochemical properties of the cell surface during a 6-month sparkling wine fermentation period. The expression of FLO1, FLO5, FLO8, AMN1 and RGA1 genes was determined by RT-qPCR. The physicochemical characterization of yeast surface properties was evaluated by the microbial adhesion to solvents method. FLO5 gene was the most expressed one and a linear correlation with the flocculent degree was found. Flocculent strains were more hydrophobic than the commercial wine strain EC1118. Gene expressions and the ability to face secondary wine fermentation conditions were strain dependent. The importance of FLO5 gene in developing the high flocculent characteristic of wine yeasts was highlighted. Cell surface properties depended on the time of fermentation. Better knowledge about the expression of some genes encoding the flocculent phenotype which could be useful to select suitable starter cultures to improve sparkling wine technology was achieved. A step forward in understanding the complexity and strain-specific nature of flocculation phenotype was done. © 2016 The Society for Applied Microbiology.

  20. Genomics and Biochemistry of Saccharomyces cerevisiae Wine Yeast Strains.

    Science.gov (United States)

    Eldarov, M A; Kishkovskaia, S A; Tanaschuk, T N; Mardanov, A V

    2016-12-01

    Saccharomyces yeasts have been used for millennia for the production of beer, wine, bread, and other fermented products. Long-term "unconscious" selection and domestication led to the selection of hundreds of strains with desired production traits having significant phenotypic and genetic differences from their wild ancestors. This review summarizes the results of recent research in deciphering the genomes of wine Saccharomyces strains, the use of comparative genomics methods to study the mechanisms of yeast genome evolution under conditions of artificial selection, and the use of genomic and postgenomic approaches to identify the molecular nature of the important characteristics of commercial wine strains of Saccharomyces. Succinctly, data concerning metagenomics of microbial communities of grapes and wine and the dynamics of yeast and bacterial flora in the course of winemaking is provided. A separate section is devoted to an overview of the physiological, genetic, and biochemical features of sherry yeast strains used to produce biologically aged wines. The goal of the review is to convince the reader of the efficacy of new genomic and postgenomic technologies as tools for developing strategies for targeted selection and creation of new strains using "classical" and modern techniques for improving winemaking technology.

  1. Interactions between yeast lees and wine polyphenols during simulation of wine aging: I. Analysis of remnant polyphenolic compounds in the resulting wines.

    Science.gov (United States)

    Mazauric, Jean-Paul; Salmon, Jean-Michel

    2005-07-13

    Wine aging on yeast lees is a traditional enological practice used during the manufacture of wines. This technique has increased in popularity in recent years for the aging of red wines. Although wine polyphenols interact with yeast lees to a limited extent, such interactions have a large effect on the reactivity toward oxygen of wine polyphenolic compounds and yeast lees. Various domains of the yeast cell wall are protected by wine polyphenols from the action of extracellular hydrolytic enzymatic activities. Polysaccharides released during autolysis are thought to exert a significant effect on the sensory qualities of wine. We studied the chemical composition of polyphenolic compounds remaining in solution or adsorbed on yeast lees after various contact times during the simulation of wine aging. The analysis of the remnant polyphenols in the wine indicated that wine polyphenols adsorption on yeast lees follows biphasic kinetics. An initial and rapid fixation is followed by a slow, constant, and saturating fixation that reaches its maximum after about 1 week. Only very few monomeric phenolic compounds remained adsorbed on yeast lees, and no preferential adsorption of low or high polymeric size tannins occurred. The remnant condensed tannins in the wine contained fewer epigallocatechin units than the initial tannins, indicating that polar condensed tannins were preferentially adsorbed on yeast lees. Conversely, the efficiency of anthocyanin adsorption on yeast lees was unrelated to its polarity.

  2. Yeast effects on Pinot noir wine phenolics, color, and tannin composition.

    Science.gov (United States)

    Carew, Anna L; Smith, Paul; Close, Dugald C; Curtin, Chris; Dambergs, Robert G

    2013-10-16

    Extraction and stabilization of wine phenolics can be challenging for wine makers. This study examined how yeast choice affected phenolic outcomes in Pinot noir wine. Five yeast treatments were applied in replicated microvinification, and wines were analyzed by UV-visible spectrophotometry. At bottling, yeast treatment Saccharomyces cerevisiae RC212 wine had significantly higher concentrations of total pigment, free anthocyanin, nonbleachable pigment, and total tannin and showed high color density. Some phenolic effects were retained at 6 months' bottle age, and RC212 and S. cerevisae EC1118 wines showed increased mean nonbleachable pigment concentrations. Wine tannin composition analysis showed three treatments were associated with a higher percentage of trihydroxylated subunits (skin tannin indicator). A high degree of tannin polymerization was observed in wines made with RC212 and Torulaspora delbruekii , whereas tannin size by gel permeation chromatography was higher only in the RC212 wines. The results emphasize the importance of yeast strain choice for optimizing Pinot noir wine phenolics.

  3. Distinct Domestication Trajectories in Top-Fermenting Beer Yeasts and Wine Yeasts.

    Science.gov (United States)

    Gonçalves, Margarida; Pontes, Ana; Almeida, Pedro; Barbosa, Raquel; Serra, Marta; Libkind, Diego; Hutzler, Mathias; Gonçalves, Paula; Sampaio, José Paulo

    2016-10-24

    Beer is one of the oldest alcoholic beverages and is produced by the fermentation of sugars derived from starches present in cereal grains. Contrary to lager beers, made by bottom-fermenting strains of Saccharomyces pastorianus, a hybrid yeast, ale beers are closer to the ancient beer type and are fermented by S. cerevisiae, a top-fermenting yeast. Here, we use population genomics to investigate (1) the closest relatives of top-fermenting beer yeasts; (2) whether top-fermenting yeasts represent an independent domestication event separate from those already described; (3) whether single or multiple beer yeast domestication events can be inferred; and (4) whether top-fermenting yeasts represent non-recombinant or recombinant lineages. Our results revealed that top-fermenting beer yeasts are polyphyletic, with a main clade composed of at least three subgroups, dominantly represented by the German, British, and wheat beer strains. Other beer strains were phylogenetically close to sake, wine, or bread yeasts. We detected genetic signatures of beer yeast domestication by investigating genes previously linked to brewing and using genome-wide scans. We propose that the emergence of the main clade of beer yeasts is related with a domestication event distinct from the previously known cases of wine and sake yeast domestication. The nucleotide diversity of the main beer clade more than doubled that of wine yeasts, which might be a consequence of fundamental differences in the modes of beer and wine yeast domestication. The higher diversity of beer strains could be due to the more intense and different selection regimes associated to brewing. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Assessment of environmental impact of commercial wine yeast in vineyard ecosystems

    OpenAIRE

    Valero, Eva; Schuller, Dorit Elisabeth; Cambon, Brigitte; Casal, Margarida; Dequin, Sylvie

    2005-01-01

    Poster e resumo apresentados no congresso "Intrafood 2005 - Innovations in traditional foods", em Valencia, Espanha, em 2005. Modern winemaking practices and diversification of wine products involve an increasing quest for specialised wine yeasts. During the last two decades considerable efforts have been made to improve wine yeast strains through the use of new biotechnologies. In the present study we used commercial wine yeast currently used in wineries as a model to assess the potential...

  5. Ethanol and sugar tolerance of wine yeasts isolated from fermenting ...

    African Journals Online (AJOL)

    Seventeen wine yeasts isolated from fermenting cashew apple juice were screened for ethanol and sugar tolerance. Two species of Saccharomyces comprising of three strains of S. cerevisiae and one S. uvarum showed measurable growth in medium containing 9% (v/v) ethanol. They were equally sugar-tolerant having ...

  6. Systematic identification of yeast proteins extracted into model wine during aging on the yeast lees.

    Science.gov (United States)

    Rowe, Jeffrey D; Harbertson, James F; Osborne, James P; Freitag, Michael; Lim, Juyun; Bakalinsky, Alan T

    2010-02-24

    Total protein and protein-associated mannan concentrations were measured, and individual proteins were identified during extraction into model wines over 9 months of aging on the yeast lees following completion of fermentations by seven wine strains of Saccharomyces cerevisiae. In aged wines, protein-associated mannan increased about 6-fold (+/-66%), while total protein only increased 2-fold (+/-20%), which resulted in a significantly greater protein-associated mannan/total protein ratio for three strains. A total of 219 proteins were identified among all wine samples taken over the entire time course. Of the 17 "long-lived" proteins detected in all 9 month samples, 13 were cell wall mannoproteins, and four were glycolytic enzymes. Most cytosolic proteins were not detected after 6 months. Native mannosylated yeast invertase was assayed for binding to wine tannin and was found to have a 10-fold lower affinity than nonglycosylated bovine serum albumin. Enrichment of mannoproteins in the aged model wines implies greater solution stability than other yeast proteins and the possibility that their contributions to wine quality may persist long after bottling.

  7. Conducting Wine Symphonics with the Aid of Yeast Genomics

    Directory of Open Access Journals (Sweden)

    Isak S. Pretorius

    2016-12-01

    Full Text Available A perfectly balanced wine can be said to create a symphony in the mouth. To achieve the sublime, both in wine and music, requires imagination and skilled orchestration of artistic craftmanship. For wine, inventiveness starts in the vineyard. Similar to a composer of music, the grapegrower produces grapes through a multitude of specifications to achieve a quality result. Different Vitis vinifera grape varieties allow the creation of wine of different genres. Akin to a conductor of music, the winemaker decides what genre to create and considers resources required to realise the grape’s potential. A primary consideration is the yeast: whether to inoculate the grape juice or leave it ‘wild’; whether to inoculate with a specific strain of Saccharomyces or a combination of Saccharomyces strains; or whether to proceed with a non-Saccharomyces species? Whilst the various Saccharomyces and non-Saccharomyces yeasts perform their role during fermentation, the performance is not over until the ‘fat lady’ (S. cerevisiae has sung (i.e., the grape sugar has been fermented to specified dryness and alcoholic fermentation is complete. Is the wine harmonious or discordant? Will the consumer demand an encore and make a repeat purchase? Understanding consumer needs lets winemakers orchestrate different symphonies (i.e., wine styles using single- or multi-species ferments. Some consumers will choose the sounds of a philharmonic orchestra comprising a great range of diverse instrumentalists (as is the case with wine created from spontaneous fermentation; some will prefer to listen to a smaller ensemble (analogous to wine produced by a selected group of non-Saccharomyces and Saccharomyces yeast; and others will favour the well-known and reliable superstar soprano (i.e., S. cerevisiae. But what if a digital music synthesizer—such as a synthetic yeast—becomes available that can produce any music genre with the purest of sounds by the touch of a few buttons

  8. Effect of ion implantation on apple wine yeast

    International Nuclear Information System (INIS)

    Song Andong; Chen Hongge; Zhang Shimin; Jia Cuiying

    2004-01-01

    The wild type apple wine yeast Y 02 was treated by ion implantation with the dose of 8 x 10 15 ion/cm 2 . As results, a special mutant strain, ION II -11 dry, was obtained. The morphology characters, partial biochemistry characters, mycelium protein of the mutant strain were distinctively changed compared with original strain Y 02 . After the fermentation test ,the apple wine producing rate of the mutant strain increased 22.4% compared with original strain. These results showed that ion implantation was an effective method for mutagenesis

  9. Replenishment and mobilization of intracellular nitrogen pools decouples wine yeast nitrogen uptake from growth

    OpenAIRE

    SANCHO FORNER, MARTA; Alicia Gutiérrez; BELTRAN CASELLAS, GEMMA; José Manuel Guillamon; Jonas Warringer

    2016-01-01

    Wine yeast capacity to take up nitrogen from the environment and catabolize it to support population growth, fermentation, and aroma production is critical to wine production. Under nitrogen restriction, yeast nitrogen uptake is believed to be intimately coupled to reproduction with nitrogen catabolite repression (NCR) suggested mediating this link. We provide a time- and strain-resolved view of nitrogen uptake, population growth, and NCR activity in wine yeasts. Nitrogen uptake was found to ...

  10. Synthetic genome engineering forging new frontiers for wine yeast.

    Science.gov (United States)

    Pretorius, Isak S

    2017-02-01

    Over the past 15 years, the seismic shifts caused by the convergence of biomolecular, chemical, physical, mathematical, and computational sciences alongside cutting-edge developments in information technology and engineering have erupted into a new field of scientific endeavor dubbed Synthetic Biology. Recent rapid advances in high-throughput DNA sequencing and DNA synthesis techniques are enabling the design and construction of new biological parts (genes), devices (gene networks) and modules (biosynthetic pathways), and the redesign of biological systems (cells and organisms) for useful purposes. In 2014, the budding yeast Saccharomyces cerevisiae became the first eukaryotic cell to be equipped with a fully functional synthetic chromosome. This was achieved following the synthesis of the first viral (poliovirus in 2002 and bacteriophage Phi-X174 in 2003) and bacterial (Mycoplasma genitalium in 2008 and Mycoplasma mycoides in 2010) genomes, and less than two decades after revealing the full genome sequence of a laboratory (S288c in 1996) and wine (AWRI1631 in 2008) yeast strain. A large international project - the Synthetic Yeast Genome (Sc2.0) Project - is now underway to synthesize all 16 chromosomes (∼12 Mb carrying ∼6000 genes) of the sequenced S288c laboratory strain by 2018. If successful, S. cerevisiae will become the first eukaryote to cross the horizon of in silico design of complex cells through de novo synthesis, reshuffling, and editing of genomes. In the meantime, yeasts are being used as cell factories for the semi-synthetic production of high-value compounds, such as the potent antimalarial artemisinin, and food ingredients, such as resveratrol, vanillin, stevia, nootkatone, and saffron. As a continuum of previously genetically engineered industrially important yeast strains, precision genome engineering is bound to also impact the study and development of wine yeast strains supercharged with synthetic DNA. The first taste of what the future

  11. Occurrence of Killer Yeast Strains in Fruit and Berry Wine Yeast Populations

    Directory of Open Access Journals (Sweden)

    Gintare Gulbiniene

    2004-01-01

    Full Text Available Apple, cranberry, chokeberry and Lithuanian red grape wine yeast populations were used for the determination of killer yeast occurrence. According to the tests of the killer characteristics and immunity the isolated strains were divided into seven groups. In this work the activity of killer toxins purified from some typical strains was evaluated. The analysed strains produced different amounts of active killer toxin and some of them possessed new industrially significant killer properties. Total dsRNA extractions in 11 killer strains of yeast isolated from spontaneous fermentations revealed that the molecular basis of the killer phenomenon was not only dsRNAs, but also unidentified genetic determinants.

  12. Evaluation of Non-Saccharomyces Yeasts for the Reduction of Alcohol Content in Wine

    Science.gov (United States)

    Contreras, A.; Hidalgo, C.; Henschke, P. A.; Chambers, P. J.; Curtin, C.

    2014-01-01

    Over recent decades, the average ethanol concentration of wine has increased, largely due to consumer preference for wine styles associated with increased grape maturity; sugar content increases with grape maturity, and this translates into increased alcohol content in wine. However, high ethanol content impacts wine sensory properties, reducing the perceived complexity of flavors and aromas. In addition, for health and economic reasons, the wine sector is actively seeking technologies to facilitate the production of wines with lower ethanol content. Nonconventional yeast species, in particular, non-Saccharomyces yeasts, have shown potential for producing wines with lower alcohol content. These yeast species, which are largely associated with grapes preharvest, are present in the early stages of fermentation but, in general, are not capable of completing alcoholic fermentation. We have evaluated 50 different non-Saccharomyces isolates belonging to 24 different genera for their capacity to produce wine with a lower ethanol concentration when used in sequential inoculation regimes with a Saccharomyces cerevisiae wine strain. A sequential inoculation of Metschnikowia pulcherrima AWRI1149 followed by an S. cerevisiae wine strain was best able to produce wine with an ethanol concentration lower than that achieved with the single-inoculum, wine yeast control. Sequential fermentations utilizing AWRI1149 produced wines with 0.9% (vol/vol) and 1.6% (vol/vol) (corresponding to 7.1 g/liter and 12.6 g/liter, respectively) lower ethanol concentrations in Chardonnay and Shiraz wines, respectively. In Chardonnay wine, the total concentration of esters and higher alcohols was higher for wines generated from sequential inoculations, whereas the total concentration of volatile acids was significantly lower. In sequentially inoculated Shiraz wines, the total concentration of higher alcohols was higher and the total concentration of volatile acids was reduced compared with those in

  13. Interactions between yeast lees and wine polyphenols during simulation of wine aging. II. Analysis of desorbed polyphenol compounds from yeast lees.

    Science.gov (United States)

    Mazauric, Jean-Paul; Salmon, Jean-Michel

    2006-05-31

    In the first part of this work, the analysis of the polyphenolic compounds remaining in the wine after different contact times with yeast lees during simulation of red wine aging was undertaken. To achieve a more precise view of the wine polyphenols adsorbed on lees during red wine aging and to establish a clear balance between adsorbed and remnant polyphenol compounds, the specific analysis of the chemical composition of the adsorbed polyphenolic compounds (condensed tannins and anthocyanins) after their partial desorbtion from yeast lees by denaturation treatments was realized in the second part of the study. The total recovery of polyphenol compounds from yeast lees was not complete, since a rather important part of the initial wine colored polyphenols, especially those with a dominant blue color component, remained strongly adsorbed on yeast lees, as monitored by color tristimulus and reflectance spectra measurements. All anthocyanins were recovered at a rather high percentage (about 62%), and it was demonstrated that they were not adsorbed in relation with their sole polarity. Very few monomeric phenolic compounds were extracted from yeast lees. With the use of drastic denaturing treatments, the total recovery of condensed tannins reached 83%. Such tannins extracted from yeast lees exhibited very high polymeric size and a rather high percentage of galloylated residues by comparison with initial wine tannins, indicating that nonpolar tannins were preferentially desorbed from yeast lees by the extraction treatments.

  14. Use of non-conventional yeast improves the wine aroma profile of Ribolla Gialla

    NARCIS (Netherlands)

    Dashko, Sofia; Zhou, Nerve; Tinta, Tinkara; Sivilotti, Paolo; Lemut, Melita Sternad; Trost, Kajetan; Gamero, Amparo; Boekhout, Teun; Butinar, Lorena; Vrhovsek, Urska; Piskur, Jure

    Consumer wine preferences are changing rapidly towards exotic flavours and tastes. In this work, we tested five non-conventional yeast strains for their potential to improve Ribolla Gialla wine quality. These strains were previously selected from numerous yeasts interesting as food production

  15. Influence of sodium chloride on wine yeast fermentation performance

    Directory of Open Access Journals (Sweden)

    Stilianos Logothetis

    2010-06-01

    Full Text Available Stilianos Logothetis1, Elias T Nerantzis2, Anna Gioulioti3, Tasos Kanelis2, Tataridis Panagiotis2, Graeme Walker11University of Abertay Dundee, School of Contemporary Sciences, Dundee, Scotland; 2TEI of Athens Department of Oenology and Spirit Technology, Biotechnology and Industrial Fermentations Lab Agiou Spiridonos, Athens, Greece; 3Ampeloiniki SA Industrial Park Thermi, Thessaloniki, GreeceAbstract: This paper concerns research into the influence of salt (sodium chloride on growth, viability and fermentation performance in a winemaking strain of the yeast, Saccharomyces cerevisiae. Experimental fermentations were conducted in both laboratory-scale and industrial-scale experiments. Preculturing yeasts in elevated levels of sodium chloride, or salt “preconditioning” led to improved fermentation performance. This was manifest by preconditioned yeasts having an improved capability to ferment high-sugar containing media with increased cell viability and with elevated levels of produced ethanol. Salt-preconditioning most likely influenced the stress-tolerance of yeasts by inducing the synthesis of key metabolites such as trehalose and glycerol. These compounds may act to improve cells’ ability to withstand osmostress and ethanol toxicity during fermentations of grape must. Industrial-scale trials using salt-preconditioned yeasts verified the benefit of this novel physiological cell engineering approach to practical winemaking fermentations.Keywords: salt, preconditioning, fermentation performance, Saccharomyces cerevisiae, wine

  16. Saccharomyces cerevisiae variety diastaticus friend or foe?-spoilage potential and brewing ability of different Saccharomyces cerevisiae variety diastaticus yeast isolates by genetic, phenotypic and physiological characterization.

    Science.gov (United States)

    Meier-Dörnberg, Tim; Kory, Oliver Ingo; Jacob, Fritz; Michel, Maximilian; Hutzler, Mathias

    2018-06-01

    Saccharomyces cerevisiae variety diastaticus is generally considered to be an obligatory spoilage microorganism and spoilage yeast in beer and beer-mixed beverages. Their super-attenuating ability causes increased carbon dioxide concentrations, beer gushing and potential bottle explosion along with changes in flavor, sedimentation and increased turbidity. This research shows clear differences in the super-attenuating properties of S. cerevisiae var. diastaticus yeast strains and their potential for industrial brewing applications. Nineteen unknown spoilage yeast cultures were obtained as isolates and characterized using a broad spectrum of genetic and phenotypic methods. Results indicated that all isolates represent genetically different S. cerevisiae var. diastaticus strains except for strain TUM PI BA 124. Yeast strains were screened for their super-attenuating ability and sporulation. Even if the STA1 gene responsible for super-attenuation by encoding for the enzyme glucoamylase could be verified by real-time polymerase chain reaction, no correlation to the spoilage potential could be demonstrated. Seven strains were further characterized focusing on brewing and sensory properties according to the yeast characterization platform developed by Meier-Dörnberg. Yeast strain TUM 3-H-2 cannot metabolize dextrin and soluble starch and showed no spoilage potential or super-attenuating ability even when the strain belongs to the species S. cerevisiae var. diastaticus. Overall, the beer produced with S. cerevisiae var. diastaticus has a dry and winey body with noticeable phenolic off-flavors desirable in German wheat beers.

  17. Novel Wine Yeast for Improved Utilisation of Proline during Fermentation

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    Danfeng Long

    2018-02-01

    Full Text Available Proline is the predominant amino acid in grape juice, but it is poorly assimilated by wine yeast under the anaerobic conditions typical of most fermentations. Exploiting the abundance of this naturally occurring nitrogen source to overcome the need for nitrogen supplementation and/or the risk of stuck or sluggish fermentations would be most beneficial. This study describes the isolation and evaluation of a novel wine yeast isolate, Q7, obtained through ethyl methanesulfonate (EMS mutagenesis. The utilisation of proline by the EMS isolate was markedly higher than by the QA23 wild type strain, with approximately 700 and 300 mg/L more consumed under aerobic and self-anaerobic fermentation conditions, respectively, in the presence of preferred nitrogen sources. Higher intracellular proline contents in the wild type strain implied a lesser rate of proline catabolism or incorporation by this strain, but with higher cell viability after freezing treatment. The expression of key genes (PUT1, PUT2, PUT3, PUT4, GAP1 and URE2 involved in proline degradation, transport and repression were compared between the parent strain and the isolate, revealing key differences. The application of these strains for efficient conduct for nitrogen-limited fermentations is a possibility.

  18. Osmotic stress response in the wine yeast Dekkera bruxellensis.

    Science.gov (United States)

    Galafassi, Silvia; Toscano, Marco; Vigentini, Ileana; Piškur, Jure; Compagno, Concetta

    2013-12-01

    Dekkera bruxellensis is mainly associated with lambic beer fermentation and wine production and may contribute in a positive or negative manner to the flavor development. This yeast is able to produce phenolic compounds, such as 4-ethylguaiacol and 4-ethylphenol which could spoil the wine, depending on their concentration. In this work we have investigated how this yeast responds when exposed to conditions causing osmotic stress, as high sorbitol or salt concentrations. We observed that osmotic stress determined the production and accumulation of intracellular glycerol, and the expression of NADH-dependent glycerol-3-phosphate dehydrogenase (GPD) activity was elevated. The involvement of the HOG MAPK pathway in response to this stress condition was also investigated. We show that in D. bruxellensis Hog1 protein is activated by phosphorylation under hyperosmotic conditions, highlighting the conserved role of HOG MAP kinase signaling pathway in the osmotic stress response. Gene Accession numbers in GenBank: DbHOG1: JX65361, DbSTL1: JX965362. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Influence of the yeast autolysates addition on the volatile compounds of sparkling white wines

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    Pérez-Magariño Silvia

    2014-01-01

    Full Text Available During sparkling wine aging, different compounds such as polysaccharides can be released due to yeast autolysis that can cause important changes in wine composition. Yeast autolysis is a slow natural process that takes long time, and the addition of some products could improve the quality of these wines. The aim of this work was to study the effect of the addition of several commercial yeast autolysates on the volatile composition of white sparkling wines (Godello and Verdejo, and aged on lees for 9 months. The discriminant analyses indicated that the sparkling wines treated with PCP2 showed the highest differences in the volatile composition of both sparkling wines studied, being the ethyl esters, terpenes, decanoic acid and some alcohols, the compounds that were affected in a greater extent. This fact could be due to PCP2 presenting the highest mannoprotein percentage that can interact with volatile compounds, modulating their volatility and perception.

  20. Outlining the influence of non-conventional yeasts in wine ageing over lees.

    Science.gov (United States)

    Belda, Ignacio; Navascués, Eva; Marquina, Domingo; Santos, Antonio; Calderón, Fernando; Benito, Santiago

    2016-07-01

    During the last decade, the use of innovative yeast cultures of both Saccharomyces cerevisiae and non-Saccharomyces yeasts as alternative tools to manage the winemaking process have turned the oenology industry. Although the contribution of different yeast species to wine quality during fermentation is increasingly understood, information about their role in wine ageing over lees is really scarce. This work aims to analyse the incidence of three non-Saccharomyces yeast species of oenological interest (Torulaspora delbrueckii, Lachancea thermotolerans and Metschnikowia pulcherrima) and of a commercial mannoprotein-overproducer S. cerevisiae strain compared with a conventional industrial yeast strain during wine ageing over lees. To evaluate their incidence in mouthfeel properties of wine after 4 months of ageing, the mannoprotein content of wines was evaluated, together with other wine analytic parameters, such as colour and aroma, biogenic amines and amino acids profile. Some differences among the studied parameters were observed during the study, especially regarding the mannoprotein concentration of wines. Our results suggest that the use of T. delbrueckii lees in wine ageing is a useful tool for the improvement of overall wine quality by notably increasing mannoproteins, reaching values higher than obtained using a S. cerevisiae overproducer strain. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  1. Synthetic biology stretching the realms of possibility in wine yeast research.

    Science.gov (United States)

    Jagtap, Umesh B; Jadhav, Jyoti P; Bapat, Vishwas A; Pretorius, Isak S

    2017-07-03

    It took several millennia to fully understand the scientific intricacies of the process through which grape juice is turned into wine. This yeast-driven fermentation process is still being perfected and advanced today. Motivated by ever-changing consumer preferences and the belief that the 'best' wine is yet to be made, numerous approaches are being pursued to improve the process of yeast fermentation and the quality of wine. Central to recent enhancements in winemaking processes and wine quality is the development of Saccharomyces cerevisiae yeast strains with improved robustness, fermentation efficiencies and sensory properties. The emerging science of Synthetic Biology - including genome engineering and DNA editing technologies - is taking yeast strain development into a totally new realm of possibility. The first example of how future wine strain development might be impacted by these new 'history-making' Synthetic Biology technologies, is the de novo production of the raspberry ketone aroma compound, 4-[4-hydroxyphenyl]butan-2-one, in a wine yeast containing a synthetic DNA cassette. This article explores how this breakthrough and the imminent outcome of the international Yeast 2.0 (or Sc2.0) project, aimed at the synthesis of the entire genome of a laboratory strain of S. cerevisiae, might accelerate the design of improved wine yeasts. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. New hybrids between Saccharomyces sensu stricto yeast species found among wine and cider production strains

    DEFF Research Database (Denmark)

    Masneuf, I; Hansen, J.; Groth, C

    1998-01-01

    Two yeast isolates, a wine-making yeast first identified as a Mel(+) strain (ex. S. uvarum) and a cider-making yeast, were characterized for their nuclear and mitochondrial genomes, Electrophoretic karyotyping analyses, restriction fragment length polymorphism maps of PCR-amplified MET2 gene...

  3. Unraveling the enzymatic basis of wine flavorome: a phylo-functional study of wine related yeast species

    Directory of Open Access Journals (Sweden)

    Ignacio eBelda

    2016-01-01

    Full Text Available Non-Saccharomyces yeasts are a heterogeneous microbial group involved in the early stages of wine fermentation. The high enzymatic potential of these yeasts makes them a useful tool for increasing the final organoleptic characteristics of wines in spite of their low fermentative power. Their physiology and contribution to wine quality are still poorly understood, with most current knowledge being acquired empirically and in most cases based in single species and strains. This work analyzed the metabolic potential of 770 yeast isolates from different enological origins and representing 15 different species, by studying their production of enzymes of enological interest and linking phylogenetic and enzymatic data. The isolates were screened for glycosidase enzymes related to terpene aroma release, the β-lyase activity responsible for the release of volatile thiols, and sulfite reductase. Apart from these aroma-related activities, protease, polygalacturonase and cellulase activities were also studied in the entire yeast collection, being related to the improvement of different technological and sensorial features of wines. In this context, and in terms of abundance, two different groups were established, with α-L-arabinofuranosidase, polygalacturonase and cellulase being the less abundant activities. By contrast, β-glucosidase and protease activities were widespread in the yeast collection studied.A classical phylogenetic study involving the partial sequencing of 26S rDNA was conducted in conjunction with the enzymatic profiles of the 770 yeast isolates for further typing, complementing the phylogenetic relationships established by using 26S rDNA. This has rendered it possible to foresee the contribution different yeast species make to wine quality and their potential applicability as pure inocula, establishing species-specific behavior. These consistent results allowed us to design future targeted studies on the impact different non

  4. Evaluation of the Components Released by Wine Yeast Strains on Protein Haze Formation in White Wine

    Directory of Open Access Journals (Sweden)

    Ellen Cristine Giese

    2016-12-01

    Full Text Available Cultures of 23 indigenous yeast strains (22 Saccharomyces cerevisiae and a non-Saccharomyces, Torulaspora delbrueckii, isolated from fermentation tanks at wineries in Castilla-La Mancha (Spain, and were performed under winemaking conditions using a synthetic must. Polysaccharide analysis and turbidity assays were conducted so as to observe the capacity of the released mannoproteins against protein haze formation in white wine, and 3 strains (2 Saccharomyces cerevisiae and T. delbrueckii were chosen for further experiments. The action of a commercial b-glucanolytic enzyme preparation (Lallzyme BETA®, and a β-(1→3-glucanase preparation from Trichoderma harzianum Rifai were evaluated to release polysaccharides from the different yeast strains’ cell walls. Protection against protein haze formation was strain dependent, and only two strains (Sc2 and Sc4 presented >50% stabilization in comparison to controls. Addition of β-glucanases did not increase the concentrations of polysaccharides in the fermentation musts; however, a significant increase of polymeric mannose (mannoproteins was detected using an enzymatic assay following total acid hydrolysis of the soluble polysaccharides. Enzymatic treatment presented positive effects and decreased protein haze formation in white wine. DOI http://dx.doi.org/10.17807/orbital.v8i6.869

  5. Strategy for Adapting Wine Yeasts for Bioethanol Production

    Directory of Open Access Journals (Sweden)

    Kevin R. Lankford

    2009-01-01

    Full Text Available The Saccharomyces cerevisiae wine yeast strains 71B-1122 and K1-V1116 were used to derive strains that could tolerate and produce higher ethanol yields. Respiratory-deficient mutants resistant to 500 mg/mL lycorine were isolated. Two mutants, 71B-1122 YEBr L3 and K1-V1116 YEBr L4, were shown to achieve about 10% and 18% improvement in their glucose-to-ethanol conversion efficiency compared to their respective parent strains. The K1-V1116 YEBr L4 in particular can tolerate an ethanol yield of 18.8 ± 0.8% at 3.5 weeks of fermentation and continued to consume most of the sugar until less than 1% glucose was left.

  6. Selection of yeast starter culture strains for the production of marula fruit wines and distillates.

    Science.gov (United States)

    Fundira, M; Blom, M; Pretorius, I S; van Rensburg, P

    2002-03-13

    Juice of the Sclerocarya birrea subsp. caffra (marula) fruit was fermented by indigenous microflora and different commercial Saccharomyces cerevisiae yeast strains at different temperatures, namely, 15 and 30 degrees C. Volatile acids, esters, and higher alcohols were quantified in the wine and distillates, and the results were interpreted using a multivariate analysis of variance and an average linkage cluster analysis. Significant differences between 15 and 30 degrees C and also among yeasts with respect to volatile compounds were observed. Yeast strains VIN7 and FC consistently produced wines and final distillates significantly different from the other strains. A panel of tasters and marula and brandy producers was asked to select wines and distillates that had an acceptable and typical marula "nose". They were also asked to detect the differences among wines and distillates fermented with the same yeast strain at different temperatures.

  7. Functionality of selected strains of moulds and yeasts from Vietnamese rice wine starters

    NARCIS (Netherlands)

    Dung, N.T.P.; Rombouts, F.M.; Nout, M.J.R.

    2006-01-01

    The role of starch-degrading mycelial fungi, and the alcohol production and ethanol tolerance of the yeasts isolated from selected Vietnamese traditional rice wine starters were examined, and optimum conditions for these essential steps in rice wine fermentation were determined. Of pure isolates

  8. Influence of different yeasts on the amino acid pattern of rosé wine

    Directory of Open Access Journals (Sweden)

    Mandl Karin

    2017-01-01

    Full Text Available In an experiment with Rosé wine, 27 different commercial yeasts were tested for their influence on the amino acid pattern of the wine. Amino acids are precursors for aromatic substances; therefore a large variation of the amino acid values in the wine was expected. Blaufränkisch grapes with 20° KMW were matured in the cellar with 27 different commercial yeasts. The fermentation was carried out in 34l vessels. The wines were measured for amino acids using an HP 1200 liquid chromatograph and HP-FLD1100 according to Umagat. The wines showed 13.5% alcohol and little residual sugar. The measurement results of the amino acids of the different wines showed large variations. For example, the amount of the amino acid alanine in wine varied from 17 to 138 mg. In particular, the wines of the yeast Pino Type showed the highest amounts of alanine in comparison to the other fermented wines.

  9. Effect of Saccharomyces, Non-Saccharomyces Yeasts and Malolactic Fermentation Strategies on Fermentation Kinetics and Flavor of Shiraz Wines

    Directory of Open Access Journals (Sweden)

    Heinrich du Plessis

    2017-12-01

    Full Text Available The use of non-Saccharomyces yeasts to improve complexity and diversify wine style is increasing; however, the interactions between non-Saccharomyces yeasts and lactic acid bacteria (LAB have not received much attention. This study investigated the interactions of seven non-Saccharomyces yeast strains of the genera Candida, Hanseniaspora, Lachancea, Metschnikowia and Torulaspora in combination with S. cerevisiae and three malolactic fermentation (MLF strategies in a Shiraz winemaking trial. Standard oenological parameters, volatile composition and sensory profiles of wines were investigated. Wines produced with non-Saccharomyces yeasts had lower alcohol and glycerol levels than wines produced with S. cerevisiae only. Malolactic fermentation also completed faster in these wines. Wines produced with non-Saccharomyces yeasts differed chemically and sensorially from wines produced with S. cerevisiae only. The Candida zemplinina and the one L. thermotolerans isolate slightly inhibited LAB growth in wines that underwent simultaneous MLF. Malolactic fermentation strategy had a greater impact on sensory profiles than yeast treatment. Both yeast selection and MLF strategy had a significant effect on berry aroma, but MLF strategy also had a significant effect on acid balance and astringency of wines. Winemakers should apply the optimal yeast combination and MLF strategy to ensure fast completion of MLF and improve wine complexity.

  10. Sequential fermentation using non-Saccharomyces yeasts for the reduction of alcohol content in wine

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    Ciani Maurizio

    2014-01-01

    Full Text Available Over the last few decades there has been a progressive increase in wine ethanol content due to global climate change and modified wine styles that involved viticulture and oenology practices. Among the different approaches and strategies to reduce alcohol content in wine we propose a sequential fermentation using immobilized non-Saccharomyces wine yeasts. Preliminary results showed that sequential fermentations with Hanseniaspora osmophila, Hanseniaspora uvarum, Metschnikowia pulcherrima, Starmerella bombicola and Saccharomyces cerevisiae strains showed an ethanol reduction when compared with pure S. cerevisiae fermentation trials.

  11. EXAMINATION OF FACTORS INFLUENCING THE VARIABILITY OF YEAST AMOUNT IN THE CONTEXT OF PH CHANGES IN BOTTLED WINES

    Directory of Open Access Journals (Sweden)

    Ladislav Mura

    2011-07-01

    Full Text Available Aim of this paper was to examine of factors (manufacturer, temperature and storage time influencing the variability of yeast amount and pH changes in bottled white wines. It was confirmed that wine coming from the business network was better quality in contract to domestic wine. We have assumed that domestic wine was contaminated during the manufacturing process, while the most probable reason was imperfect filtration of wine, or its contamination during the bottling. The results showed that the way of storage wine in the room, resp. cooler temperature did not significant effect on changes in the amount of yeast (p-hodnota=0.2080. Regarding the period of storage of wine, the conclusions are identical to the previous factor, ie. storage time not significantly impacted amount of yeast in wine (p-value=0.5507. doi:10.5219/151 

  12. Development and characterization of hybrids from native wine yeasts

    Directory of Open Access Journals (Sweden)

    Verónica García

    2012-06-01

    Full Text Available For commercial purposes, the winemaking industry is constantly searching for new yeast strains. Historically, this has been achieved by collecting wild strains and selecting the best for industrial use through an enological evaluation. Furthermore, the increasing consumer demands have forced the industry to incorporate new strategies such as genetic engineering to obtain improved strains. In response to the lack of public acceptance of this methodology, alternative strategies based on breeding have gained acceptance in recent years. Through the use of conjugation of individual spores without the support of genetic engineering methods we generated intraspecific hybrids from wild strains with outstanding enological characteristics and interdelta fingerprinting was used to confirm the hybrid condition. A detailed enological characterization of the hybrids in synthetic and natural must indicates that physiological parameters such as sporulation, residual sugar, ethanol yield and total nitrogen uptake are within the levels determined for the parental strains, however, other parameters such as growth rate, lag phase and ethanol production show statistical differences with some parental or commercial strains. These findings allow us to propose these hybrids as new wine-making strains.

  13. Effect of Protectants on the Fermentation Performance of Wine Yeasts Subjected to Osmotic Stress

    Directory of Open Access Journals (Sweden)

    Andrea Caridi

    2003-01-01

    Full Text Available During alcoholic fermentation of must from dried grapes, yeasts are subjected to very high sugar concentrations, besides other environmental stresses, and they modify their metabolic behaviour giving low ethanol yield and abnormally high acetic acid production. To investigate the protective effect of catechin, inositol, and SO2 on wine yeasts, three thermotolerant strains of Saccharomyces cerevisiae, selected for wine making of must from dried grapes, and three strains of Saccharomyces selected for the production of wine, were inoculated in a sample of must at very high osmotic strength. A significant (p<0.01 or p<0.05 relationship between the addition of 100 mg/L of catechin, inositol or SO2 to the grape must and the change in the metabolic behaviour of the yeasts was observed. Compared to the control and depending on strain and protectant, the fermentation rate after 3 days increased up to 55 %, the ethanol content of the wines increased up to 16 %, the unitary succinic acid production increased up to 55 %, the unitary acetic acid production decreased up to 53 %, and the unitary glycerol production decreased up to 69 %. So by adding catechin, inositol or SO2 to the grape must it is possible to minimise the abnormal fermentation performance that wine yeasts exhibit in wine making of must from dried grapes.

  14. Influence of Tannin Extract and Yeast Extract on Color Preservation and Anthocyanin Content of Mulberry Wine.

    Science.gov (United States)

    You, Yilin; Li, Na; Han, Xue; Guo, Jielong; Liu, Guojie; Huang, Weidong; Zhan, Jicheng

    2018-04-01

    The color of mulberry wine is extremely unstable in processing and aging. This paper investigates the effects of tannin extract and yeast extract on the color and color-preserving characteristics of mulberry wine made from the Dashi cultivar. The results showed that the maximum absorption wavelength in both tannin extract and yeast extract groups changed generating the red shift effect. The color of the tannin extract maintained a good gloss in the first 4 months, while the yeast extract group showed remarkable color preservation for the first 3 months. The total anthocyanin and cyanidin-3-rutinoside contents in both experiment groups were significantly higher than that of the control group, thus proving that tannin extract and yeast extract both exert a remarkably positive effect on preserving the color of mulberry wine during its aging. Moreover, sensory analysis indicated that the quality of mulberry wine treated with tannin extract was significantly higher than that of the control. The distinct color of mulberry wine is one of the foremost qualities that imprints on consumers' senses, but it is extremely unstable in processing and aging. However, the color protection of mulberry wine was not studied previously. In this study, we found that tannin extract and yeast extract both exert a remarkably positive effect on preserving the color of mulberry wine during aging. The study is of great significance as a guide to improving the color stability of mulberry wine, thereby also improving and promoting the development of the mulberry deep processing industry. © 2018 Institute of Food Technologists®.

  15. Yeast alter micro-oxygenation of wine: oxygen consumption and aldehyde production.

    Science.gov (United States)

    Han, Guomin; Webb, Michael R; Richter, Chandra; Parsons, Jessica; Waterhouse, Andrew L

    2017-08-01

    Micro-oxygenation (MOx) is a common winemaking treatment used to improve red wine color development and diminish vegetal aroma, amongst other effects. It is commonly applied to wine immediately after yeast fermentation (phase 1) or later, during aging (phase 2). Although most winemakers avoid MOx during malolactic (ML) fermentation, it is often not possible to avoid because ML bacteria are often present during phase 1 MOx treatment. We investigated the effect of common yeast and bacteria on the outcome of micro-oxygenation. Compared to sterile filtered wine, Saccharomyces cerevisiae inoculation significantly increased oxygen consumption, keeping dissolved oxygen in wine below 30 µg L -1 during micro-oxygenation, whereas Oenococcus oeni inoculation was not associated with a significant impact on the concentration of dissolved oxygen. The unfiltered baseline wine also had both present, although with much higher populations of bacteria and consumed oxygen. The yeast-treated wine yielded much higher levels of acetaldehyde, rising from 4.3 to 29 mg L -1 during micro-oxygenation, whereas no significant difference was found between the bacteria-treated wine and the filtered control. The unfiltered wine exhibited rapid oxygen consumption but no additional acetaldehyde, as well as reduced pyruvate. Analysis of the acetaldehyde-glycerol acetal levels showed a good correlation with acetaldehyde concentrations. The production of acetaldehyde is a key outcome of MOx and it is dramatically increased in the presence of yeast, although it is possibly counteracted by the metabolism of O. oeni bacteria. Additional controlled experiments are necessary to clarify the interaction of yeast and bacteria during MOx treatments. Analysis of the glycerol acetals may be useful as a proxy for acetaldehyde levels. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  16. Population analysis of biofilm yeasts during fino sherry wine aging in the Montilla-Moriles D.O. region.

    Science.gov (United States)

    Marin-Menguiano, Miriam; Romero-Sanchez, Sandra; Barrales, Ramón R; Ibeas, Jose I

    2017-03-06

    Fino is the most popular sherry wine produced in southern Spain. Fino is matured by biological aging under a yeast biofilm constituted of Saccharomyces cerevisiae yeasts. Although different S. cerevisiae strains can be identified in such biofilms, their diversity and contribution to wine character have been poorly studied. In this work, we analyse the flor yeast population in five different wineries from the Montilla-Moriles D.O. (Denominación de Origen) in southern Spain. Yeasts present in wines of different ages were identified using two different culture-dependent molecular techniques. From 2000 individual yeast isolates, five different strains were identified with one of them dominating in four out of the five wineries analysed, and representing 76% of all the yeast isolates collected. Surprisingly, this strain is similar to the predominant strain isolated twenty years ago in Jerez D.O. wines, suggesting that this yeast is particularly able to adapt to such a stressful environment. Fino wine produced with pure cultures of three of the isolated strains resulted in different levels of acetaldehyde. Because acetaldehyde levels are a distinctive characteristic of fino wines and an indicator of fino aging, the use of molecular techniques for yeast identification and management of yeast populations may be of interest for fino wine producers looking to control one of the main features of this wine. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Performance of mycological media in enumerating desiccated food spoilage yeasts: an interlaboratory study.

    Science.gov (United States)

    Beuchat, L R; Frandberg, E; Deak, T; Alzamora, S M; Chen, J; Guerrero, A S; López-Malo, A; Ohlsson, I; Olsen, M; Peinado, J M; Schnurer, J; de Siloniz, M I; Tornai-Lehoczki, J

    2001-10-22

    Dichloran 18% glycerol agar (DG18) was originally formulated to enumerate nonfastidious xerophilic moulds in foods containing rapidly growing Eurotium species. Some laboratories are now using DG18 as a general purpose medium for enumerating yeasts and moulds, although its performance in recovering yeasts from dry foods has not been evaluated. An interlaboratory study compared DG18 with dichloran rose bengal chloramphenicol agar (DRBC), plate count agar supplemented with chloramphenicol (PCAC), tryptone glucose yeast extract chloramphenicol agar (TGYC), acidified potato dextrose agar (APDA), and orange serum agar (OSA) for their suitability to enumerate 14 species of lyophilized yeasts. The coefficient of variation for among-laboratories repeatability within yeast was 1.39% and reproducibility of counts among laboratories was 7.1%. The order of performance of media for recovering yeasts was TGYC > PCAC = OSA > APDA > DRBC > DG 18. A second study was done to determine the combined effects of storage time and temperature on viability of yeasts and suitability of media for recovery. Higher viability was retained at -18 degrees C than at 5 degrees C or 25 degrees C for up to 42 weeks, although the difference in mean counts of yeasts stored at -18 degrees C and 25 degrees C was only 0.78 log10 cfu/ml of rehydrated suspension. TGYC was equal to PCAC and superior to the other four media in recovering yeasts stored at -18 degrees C, 5 degrees C, or 25 degrees C for up to 42 weeks. Results from both the interlaboratory study and the storage study support the use of TGYC for enumerating desiccated yeasts. DG18 is not recommended as a general purpose medium for recovering yeasts from a desiccated condition.

  18. Effect of increased yeast alcohol acetyltransferase activity on flavor profiles of wine and distillates.

    Science.gov (United States)

    Lilly, M; Lambrechts, M G; Pretorius, I S

    2000-02-01

    The distinctive flavor of wine, brandy, and other grape-derived alcoholic beverages is affected by many compounds, including esters produced during alcoholic fermentation. The characteristic fruity odors of the fermentation bouquet are primarily due to a mixture of hexyl acetate, ethyl caproate (apple-like aroma), iso-amyl acetate (banana-like aroma), ethyl caprylate (apple-like aroma), and 2-phenylethyl acetate (fruity, flowery flavor with a honey note). The objective of this study was to investigate the feasibility of improving the aroma of wine and distillates by overexpressing one of the endogenous yeast genes that controls acetate ester production during fermentation. The synthesis of acetate esters by the wine yeast Saccharomyces cerevisiae during fermentation is ascribed to at least three acetyltransferase activities, namely, alcohol acetyltransferase (AAT), ethanol acetyltransferase, and iso-amyl AAT. To investigate the effect of increased AAT activity on the sensory quality of Chenin blanc wines and distillates from Colombar base wines, we have overexpressed the alcohol acetyltransferase gene (ATF1) of S. cerevisiae. The ATF1 gene, located on chromosome XV, was cloned from a widely used commercial wine yeast strain of S. cerevisiae, VIN13, and placed under the control of the constitutive yeast phosphoglycerate kinase gene (PGK1) promoter and terminator. Chromoblot analysis confirmed the integration of the modified copy of ATF1 into the genome of three commercial wine yeast strains (VIN7, VIN13, and WE228). Northern blot analysis indicated constitutive expression of ATF1 at high levels in these yeast transformants. The levels of ethyl acetate, iso-amyl acetate, and 2-phenylethyl acetate increased 3- to 10-fold, 3.8- to 12-fold, and 2- to 10-fold, respectively, depending on the fermentation temperature, cultivar, and yeast strain used. The concentrations of ethyl caprate, ethyl caprylate, and hexyl acetate only showed minor changes, whereas the acetic acid

  19. Bread, beer and wine: yeast domestication in the Saccharomyces sensu stricto complex.

    Science.gov (United States)

    Sicard, Delphine; Legras, Jean-Luc

    2011-03-01

    Yeasts of the Saccharomyces sensu stricto species complex are able to convert sugar into ethanol and CO(2) via fermentation. They have been used for thousands years by mankind for fermenting food and beverages. In the Neolithic times, fermentations were probably initiated by naturally occurring yeasts, and it is unknown when humans started to consciously add selected yeast to make beer, wine or bread. Interestingly, such human activities gave rise to the creation of new species in the Saccharomyces sensu stricto complex by interspecies hybridization or polyploidization. Within the S. cerevisiae species, they have led to the differentiation of genetically distinct groups according to the food process origin. Although the evolutionary history of wine yeast populations has been well described, the histories of other domesticated yeasts need further investigation. Copyright © 2011 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  20. Optimization of carbon and nitrogen medium components for biomass production using non-Saccharomyces wine yeasts.

    Science.gov (United States)

    Schnierda, T; Bauer, F F; Divol, B; van Rensburg, E; Görgens, J F

    2014-05-01

    The impact of different nitrogen and carbon sources on biomass production of the non-Saccharomyces wine yeast species Lachancea thermotolerans, Metschnikowia pulcherrima and Issatchenkia orientalis was assessed. Using a molasses-based medium, yeast extract and corn steep liquor as well as ammonium sulphate and di-ammonium phosphate (DAP) as nitrogen sources were compared in shake-flask cultures. A medium with 20 g l⁻¹ sugar (diluted molasses) and 500 mg l⁻¹ total yeast assimilable nitrogen, from yeast extract, gave the highest biomass concentrations and yields. Invertase pretreatment was required for cultures of M. pulcherrima and I. orientalis, and respective biomass yields of 0.7 and 0.8 g g⁻¹ were achieved in aerobic bioreactor cultures. The absence of ethanol production suggested Crabtree-negative behaviour by these yeasts, whereas Crabtree-positive behaviour by L. thermotolerans resulted in ethanol and biomass concentrations of 5.5 and 11.1 g l⁻¹, respectively. Recent studies demonstrate that non-Saccharomyces yeasts confer positive attributes to the final composition of wine. However, optimal process conditions for their biomass production have not been described, thereby limiting commercial application. In this study, industrial media and methods of yeast cultivation were investigated to develop protocols for biomass production of non-Saccharomyces yeast starter cultures for the wine industry. © 2014 The Society for Applied Microbiology.

  1. Different commercial yeast strains affecting the volatile and sensory profile of cava base wine.

    Science.gov (United States)

    Torrens, Jordi; Urpí, Pilar; Riu-Aumatell, Montserrat; Vichi, Stefania; López-Tamames, Elvira; Buxaderas, Susana

    2008-05-10

    36 semi-industrial fermentations were carried out with 6 different yeast strains in order to assess differences in the wines' chemical and volatile profile. Two of the tested strains (Y3 and Y6) showed the fastest fermentation rates throughout 3 harvests and on 2 grape varieties. The wines fermented by three of the tested strains (Y5, Y3 and Y4) stand out for their high amounts of esters and possessed the highest fruity character. Wines from strains producing low amounts of esters and high concentrations of medium chain fatty acids, higher alcohols and six-carbon alcohols were the least appreciated at the sensory analysis. The data obtained in the present study show how the yeast strain quantitatively affects the final chemical and volatile composition of cava base wines and have repercussions on their sensory profile, independently of must variety and harvest year.

  2. Genomic signatures of adaptation to wine biological ageing conditions in biofilm-forming flor yeasts.

    Science.gov (United States)

    Coi, A L; Bigey, F; Mallet, S; Marsit, S; Zara, G; Gladieux, P; Galeote, V; Budroni, M; Dequin, S; Legras, J L

    2017-04-01

    The molecular and evolutionary processes underlying fungal domestication remain largely unknown despite the importance of fungi to bioindustry and for comparative adaptation genomics in eukaryotes. Wine fermentation and biological ageing are performed by strains of S. cerevisiae with, respectively, pelagic fermentative growth on glucose and biofilm aerobic growth utilizing ethanol. Here, we use environmental samples of wine and flor yeasts to investigate the genomic basis of yeast adaptation to contrasted anthropogenic environments. Phylogenetic inference and population structure analysis based on single nucleotide polymorphisms revealed a group of flor yeasts separated from wine yeasts. A combination of methods revealed several highly differentiated regions between wine and flor yeasts, and analyses using codon-substitution models for detecting molecular adaptation identified sites under positive selection in the high-affinity transporter gene ZRT1. The cross-population composite likelihood ratio revealed selective sweeps at three regions, including in the hexose transporter gene HXT7, the yapsin gene YPS6 and the membrane protein coding gene MTS27. Our analyses also revealed that the biological ageing environment has led to the accumulation of numerous mutations in proteins from several networks, including Flo11 regulation and divalent metal transport. Together, our findings suggest that the tuning of FLO11 expression and zinc transport networks are a distinctive feature of the genetic changes underlying the domestication of flor yeasts. Our study highlights the multiplicity of genomic changes underlying yeast adaptation to man-made habitats and reveals that flor/wine yeast lineage can serve as a useful model for studying the genomics of adaptive divergence. © 2017 John Wiley & Sons Ltd.

  3. In vitro antifungal effect of black cumin seed quinones against dairy spoilage yeasts at different acidity levels.

    Science.gov (United States)

    Halamova, Katerina; Kokoska, Ladislav; Flesar, Jaroslav; Sklenickova, Olga; Svobodova, Blanka; Marsik, Petr

    2010-12-01

    The antiyeast activity of the black cumin seed (Nigella sativa) quinones dithymoquinone, thymohydroquinone (THQ), and thymoquinone (TQ) were evaluated in vitro with a broth microdilution method against six dairy spoilage yeast species. Antifungal effects of the quinones were compared with those of preservatives commonly used in milk products (calcium propionate, natamycin, and potassium sorbate) at two pH levels (4.0 and 5.5). THQ and TQ possessed significant antiyeast activity and affected the growth of all strains tested at both pH levels, with MICs ranging from 8 to 128 μg/ml. With the exception of the antibiotic natamycin, the inhibitory effects of all food preservatives against the yeast strains tested in this study were strongly affected by differences in pH, with MICs of ≥16 and ≥512 μg/ml at pH 4.0 and 5.5, respectively. These findings suggest that HQ and TQ are effective antiyeast agents that could be used in the dairy industry as chemical preservatives of natural origin.

  4. Potential of high pressure homogenization to induce autolysis of wine yeasts.

    Science.gov (United States)

    Comuzzo, Piergiorgio; Calligaris, Sonia; Iacumin, Lucilla; Ginaldi, Federica; Palacios Paz, Anthony Efrain; Zironi, Roberto

    2015-10-15

    High pressure homogenization (HPH) was tested for inducing autolysis in a commercial strain of Saccharomyces bayanus for winemaking. The effects on cell viability, the release of soluble proteins, glucidic colloids and amino acids in wine-like medium and the volatile composition of the autolysates were investigated after processing, in comparison with thermolysis. HPH seemed a promising technique for inducing autolysis of wine yeasts. One pass at 150 MPa was the best operating conditions. Soluble colloids, proteins and free amino acids were similar after HPH and thermolysis, but the former gave a more interesting volatile composition after processing, with higher concentrations of ethyl esters (fruity odors) and lower fatty acids (potential off-flavors). This might allow different winemaking applications for HPH, such as the production of yeast derivatives for wine ageing. In the conditions tested, HPH did not allow the complete inactivation of yeast cells; the treatment shall be optimized before winemaking use. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Production of fermentation aroma compounds by Saccharomyces cerevisiae wine yeasts: effects of yeast assimilable nitrogen on two model strains.

    Science.gov (United States)

    Carrau, Francisco M; Medina, Karina; Farina, Laura; Boido, Eduardo; Henschke, Paul A; Dellacassa, Eduardo

    2008-11-01

    The contribution of yeast fermentation metabolites to the aromatic profile of wine is well documented; however, the biotechnological application of this knowledge, apart from strain selection, is still rather limited and often contradictory. Understanding and modeling the relationship between nutrient availability and the production of desirable aroma compounds by different strains must be one of the main objectives in the selection of industrial yeasts for the beverage and food industry. In order to overcome the variability in the composition of grape juices, we have used a chemically defined model medium for studying yeast physiological behavior and metabolite production in response to nitrogen supplementation so as to identify an appropriate yeast assimilable nitrogen level for strain differentiation. At low initial nitrogen concentrations, strain KU1 produced higher quantities of esters and fatty acids whereas M522 produced higher concentrations of isoacids, gamma-butyrolactone, higher alcohols and 3-methylthio-1-propanol. We propose that although strains KU1 and M522 have a similar nitrogen consumption profile, they represent useful models for the chemical characterization of wine strains in relation to wine quality. The differential production of aroma compounds by the two strains is discussed in relation to their capacity for nitrogen usage and their impact on winemaking. The results obtained here will help to develop targeted metabolic footprinting methods for the discrimination of industrial yeasts.

  6. Interactions of grape tannins and wine polyphenols with a yeast protein extract, mannoproteins and β-glucan

    OpenAIRE

    Mekoue Nguela, Julie; Poncet-Legrand, Celine; Sieczkowski, N.; Vernhet, Aude

    2016-01-01

    At present, there is a great interest in enology for yeast derived products to replace aging on lees in winemaking or as an alternative for wine fining. These are yeast protein extracts (YPE), cell walls and mannoproteins. Our aim was to further understand the mechanisms that drive interactions between these components and red wine polyphenols. To this end, interactions between grape skin tannins or wine polyphenols or tannins and a YPE, a mannoprotein fraction and a β-glucan were monitored b...

  7. Microbial terroir and food innovation: The case of yeast biodiversity in wine.

    Science.gov (United States)

    Capozzi, Vittorio; Garofalo, Carmela; Chiriatti, Maria Assunta; Grieco, Francesco; Spano, Giuseppe

    2015-12-01

    Saccharomyces and non-Saccharomyces represents a heterogeneous class in the grape/must/wine environments including several yeast genera (e.g., Saccharomyces, Hanseniaspora, Pichia, Candida, Metschnikowia, Kluyveromyces, Zygosaccharomyces, Torulaspora, Dekkera and Schizosaccharomyces) and species. Since, each species may differently contribute to the improvement/depreciation of wine qualities, it appears clear the reason why species belong to non-Saccharomyces are also considered a biotechnological resource in wine fermentation. Here, we briefly review the oenological significance of this specific part of microbiota associated with grapes/musts/wine. Moreover, the diversity of cultivable non-Saccharomyces genera and their contribute to typical wines fermentations will be discussed. Copyright © 2015 Elsevier GmbH. All rights reserved.

  8. Volatile phenols in wine: Control measures of Brettanomyces/Dekkera yeasts

    Directory of Open Access Journals (Sweden)

    Sanja Šućur

    2016-10-01

    Full Text Available This review focuses on the considerable amount of research regarding volatile phenols production by Brettanomyces and on microbiological and technological parameters that influence development of these compounds during all stages of grape processing and winemaking. Also, volatile phenols impact on wine aroma and quality and prevention methods were discussed. The yeast genus Brettanomyces is the major microorganism that has the ability to convert hydroxycinnamic acids into significant concentration of phenolic compounds, especially of 4-ethylphenol and 4-ethylguaiacol, in red wine. When volatile phenols reach concentrations above the sensory threshold in wine, it is then characterized as wine with fault. In order to control the growth of Brettanomyces and preclude volatile phenols production, it is helpful to keep good quality of grape, winery sanitation, control of oxygen and sulphite level, as well as orderly check physiochemical composition of wine.

  9. Yeast multistress resistance and lag-phase characterisation during wine fermentation.

    Science.gov (United States)

    Ferreira, David; Galeote, Virginie; Sanchez, Isabelle; Legras, Jean-Luc; Ortiz-Julien, Anne; Dequin, Sylvie

    2017-09-01

    Saccharomyces cerevisiae has been used to perform wine fermentation for several millennia due to its endurance and unmatched qualities. Nevertheless, at the moment of inoculation, wine yeasts must cope with specific stress factors that still challenge wine makers by slowing down or compromising the fermentation process. To better assess the role of genetic and environmental factors that govern multistress resistance during the wine fermentation lag phase, we used a factorial plan to characterise the individual and combined impact of relevant stress factors on eight S. cerevisiae and two non-S. cerevisiae wine yeast strains that are currently commercialised. The S. cerevisiae strains are very genetically diverse, belonging to the wine and flor groups, and frequently contain a previously described XVIVIII translocation that confers increased resistance to sulphites. We found that low temperature and osmotic stress substantially affected all strains, promoting considerably extended lag phases. SO2 addition had a partially temperature-dependent effect, whereas low phytosterol and thiamine concentrations impacted the lag phase in a strain-dependent manner. No major synergic effects of multistress were detected. The diversity of lag-phase durations and stress responses observed among wine strains offer new insights to better control this critical step of fermentation. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  10. Yeast Autolysis in Sparkling Wine Aging: Use of Killer and Sensitive Saccharomyces cerevisiae Strains in Co-Culture.

    Science.gov (United States)

    Lombardi, Silvia Jane; De Leonardis, Antonella; Lustrato, Giuseppe; Testa, Bruno; Iorizzo, Massimo

    2015-01-01

    Sparkling wines produced by traditional method owe their characteristics to secondary fermentation and maturation that occur during a slow ageing in bottles. Yeast autolysis plays an important role during the sparkling wine aging. Using a combination of killer and sensitive yeasts is possible to accelerate yeast autolysis and reduce maturing time. killer and sensitive Saccharomyces cerevisiae strains, separately and in co-cultures, were inoculated in base wine and bottled on pilot-plant scale. Commercial Saccaromyces bayanus strain was also investigated. Protein free amino acid and polysaccharides contents and sensory analysis were determined on the wine samples at 3, 6 and 9 months of aging. Yeast autolysis that occurs during the production of sparkling wines, obtained with co-cultures of killer and sensitive strains, has influenced free amino acids, total protein and polysaccharides content after 3 months aging time: sparkling wines, produced without the use of these yeasts, have reached the same results only after 9 months aging time. These results demonstrate that killer and sensitive yeasts in co-culture can accelerate the onset of autolysis in enological conditions, and has a positive effect on the quality of the aroma and flavor of sparkling wine. This paper offers an interesting biotechnological method to reduce production time of sparkling wine with economical benefits for the producers. We revised all patents relating to sparkling wine considering only those of interest for our study.

  11. Antioxidant defense parameters as predictive biomarkers for fermentative capacity of active dried wine yeast.

    Science.gov (United States)

    Gamero-Sandemetrio, Esther; Gómez-Pastor, Rocío; Matallana, Emilia

    2014-08-01

    The production of active dried yeast (ADY) is a common practice in industry for the maintenance of yeast starters and as a means of long term storage. The process, however, causes multiple cell injuries, with oxidative damage being one of the most important stresses. Consequentially, dehydration tolerance is a highly appreciated property in yeast for ADY production. In this study we analyzed the cellular redox environment in three Saccharomyces cerevisiae wine strains, which show markedly different fermentative capacities after dehydration. To measure/quantify the effect of dehydration on the S. cerevisiae strains, we used: (i) fluorescent probes; (ii) antioxidant enzyme activities; (ii) intracellular damage; (iii) antioxidant metabolites; and (iv) gene expression, to select a minimal set of biochemical parameters capable of predicting desiccation tolerance in wine yeasts. Our results show that naturally enhanced antioxidant defenses prevent oxidative damage after wine yeast biomass dehydration and improve fermentative capacity. Based on these results we chose four easily assayable parameters/biomarkers for the selection of industrial yeast strains of interest for ADY production: trehalose and glutathione levels, and glutathione reductase and catalase enzymatic activities. Yeast strains selected in accordance with this process display high levels of trehalose, low levels of oxidized glutathione, a high induction of glutathione reductase activity, as well as a high basal level and sufficient induction of catalase activity, which are properties inherent in superior ADY strains. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Impact of glutathione-enriched inactive dry yeast preparations on the stability of terpenes during model wine aging

    OpenAIRE

    Rodríguez-Bencomo, Juan José; Andújar-Ortiz, Inmaculada; Moreno-Arribas, M. Victoria; Simó, Carolina; González, Javier; Chana, Antonio; Dávalos, J.Z.; Pozo-Bayón, Mª Ángeles

    2014-01-01

    The impact of the addition of glutathione-enriched Inactive dry yeast preparations (g-IDYs) on the stability of some typical wine terpenes (linalool, α-terpineol, β-citronellol, and nerol) stored under accelerated oxidative conditions was evaluated in model wines. Additionally, the effects of a second type of IDY preparation with a different claim (fermentative nutrient) and the sole addition of commercial glutathione into the model wines were also assessed. Model wines were spiked with the l...

  13. Non-conventional yeast species for lowering ethanol content of wines

    Directory of Open Access Journals (Sweden)

    Maurizio eCiani

    2016-05-01

    Full Text Available Rising sugar content in grape must, and the concomitant increase in alcohol levels in wine, are some of the main challenges affecting the winemaking industry nowadays. Among the several alternative solutions currently under study, the use of non-conventional yeasts during fermentation holds good promise for contributing to relieve this problem. Non-Saccharomyces wine yeast species comprise a high number or species, so encompassing a wider physiological diversity than Saccharomyces cerevisiae. Indeed, the current oenological interest of these microorganisms was initially triggered by their potential positive contribution to the sensorial complexity of quality wines, through the production of aroma and other sensory-active compounds. This diversity also involves ethanol yield on sugar, one of the most invariant metabolic traits of S. cerevisiae. This review gathers recent research on non-Saccharomyces yeasts, aiming to produce wines with lower alcohol content than those from pure Saccharomyces starters. Critical aspects discussed include the selection of suitable yeast strains (considering there is a noticeable intra-species diversity for ethanol yield, as shown for other fermentation traits, identification of key environmental parameters influencing ethanol yields (including the use of controlled oxygenation conditions, and managing mixed fermentations, by either the sequential or simultaneous inoculation of S. cerevisiae and non-Saccharomyces starter cultures. The feasibility, at the industrial level, of using non-Saccharomyces yeasts for reducing alcohol levels in wine will require an improved understanding of the metabolism of these alternative yeast species, as well as of the interactions between different yeast starters during the fermentation of grape must.

  14. Non-conventional Yeast Species for Lowering Ethanol Content of Wines

    Science.gov (United States)

    Ciani, Maurizio; Morales, Pilar; Comitini, Francesca; Tronchoni, Jordi; Canonico, Laura; Curiel, José A.; Oro, Lucia; Rodrigues, Alda J.; Gonzalez, Ramon

    2016-01-01

    Rising sugar content in grape must, and the concomitant increase in alcohol levels in wine, are some of the main challenges affecting the winemaking industry nowadays. Among the several alternative solutions currently under study, the use of non-conventional yeasts during fermentation holds good promise for contributing to relieve this problem. Non-Saccharomyces wine yeast species comprise a high number or species, so encompassing a wider physiological diversity than Saccharomyces cerevisiae. Indeed, the current oenological interest of these microorganisms was initially triggered by their potential positive contribution to the sensorial complexity of quality wines, through the production of aroma and other sensory-active compounds. This diversity also involves ethanol yield on sugar, one of the most invariant metabolic traits of S. cerevisiae. This review gathers recent research on non-Saccharomyces yeasts, aiming to produce wines with lower alcohol content than those from pure Saccharomyces starters. Critical aspects discussed include the selection of suitable yeast strains (considering there is a noticeable intra-species diversity for ethanol yield, as shown for other fermentation traits), identification of key environmental parameters influencing ethanol yields (including the use of controlled oxygenation conditions), and managing mixed fermentations, by either the sequential or simultaneous inoculation of S. cerevisiae and non-Saccharomyces starter cultures. The feasibility, at the industrial level, of using non-Saccharomyces yeasts for reducing alcohol levels in wine will require an improved understanding of the metabolism of these alternative yeast species, as well as of the interactions between different yeast starters during the fermentation of grape must. PMID:27199967

  15. Characterization of volatile fraction of typical Irpinian wines fermented with a new starter yeast.

    Science.gov (United States)

    Calabretti, A; La Cara, F; Sorrentino, A; Di Stasio, M; Santomauro, F; Rastrelli, L; Gabrielli, L; Limone, F; Volpe, M G

    2012-04-01

    Non-Saccharomyces yeasts are microorganisms that play an important role in the fermentation dynamics, compositions and flavour of wine. The aromatic compounds responsible for varietal aroma in wine are mainly terpenes, of which the most important group are the monoterpenes because of their volatility and odour if present in a free form. In fact, some terpenyl-glycosides do not contribute to the aroma unless they are hydrolysed. The glycosylated form of terpenes can be converted by hydrolysis with β-glycosidases produced by yeasts during the winemaking process, into aromatic compounds. In this study we utilized a non-Saccharomyces yeast, with a high extra-cellular glycosidase activity, isolated from grapes of cultivars typical of Irpinia region. This strain, identified as a Rhodotorula mucillaginosa (strain WLR12), was used to carry out an experimental winemaking process and the results were compared with those obtained with a commercial yeast starter. Chemical and sensorial analysis demonstrated that the wines produced with WLR12 strain had a more floral aroma and some sweet and ripened fruit notes compared to those obtained with commercial yeast. The data also showed an increasing of the free terpenes fraction that, however, did not significatively modify the bouquet of the wines.

  16. Improved Screening Method for the Selection of Wine Yeasts Based on Their Pigment Adsorption Activity

    Directory of Open Access Journals (Sweden)

    Andrea Caridi

    2013-01-01

    Full Text Available The aim of this research is to improve an existing low-cost and simple but consistent culturing technique for measuring the adsorption of grape skin pigments on yeasts, comprising: (i growing yeasts in Petri dishes on chromogenic grape-skin-based medium, (ii photographing the yeast biomass, (iii measuring its red, green, and blue colour components, and (iv performing the statistical analysis of the data. Twenty strains of Saccharomyces cerevisiae were grown on different lots of the chromogenic medium, prepared using grape skins from dark cultivars Greco Nero, Magliocco and Nero d’Avola. Microscale wine fermentation trials were also performed. Wide and significant differences among wine yeasts were observed. The chromogenic grape-skin-based medium can be prepared using any grape cultivar, thus allowing the specific selection of the most suitable strain of Saccharomyces cerevisiae for each grape must, mainly for red winemaking. The research provides a useful tool to characterize wine yeasts in relation to pigment adsorption, allowing the improvement of wine colour.

  17. Functional analysis of lipid metabolism genes in wine yeasts during alcoholic fermentation at low temperature.

    Science.gov (United States)

    López-Malo, María; García-Ríos, Estéfani; Chiva, Rosana; Guillamon, José M

    2014-10-29

    Wine produced by low-temperature fermentation is mostly considered to have improved sensory qualities. However few commercial wine strains available on the market are well-adapted to ferment at low temperature (10 - 15°C). The lipid metabolism of Saccharomyces cerevisiae plays a central role in low temperature adaptation. One strategy to modify lipid composition is to alter transcriptional activity by deleting or overexpressing the key genes of lipid metabolism. In a previous study, we identified the genes of the phospholipid, sterol and sphingolipid pathways, which impacted on growth capacity at low temperature. In the present study, we aimed to determine the influence of these genes on fermentation performance and growth during low-temperature wine fermentations. We analyzed the phenotype during fermentation at the low and optimal temperature of the lipid mutant and overexpressing strains in the background of a derivative commercial wine strain. The increase in the gene dosage of some of these lipid genes, e.g., PSD1 , LCB3, DPL1 and OLE1, improved fermentation activity during low-temperature fermentations, thus confirming their positive role during wine yeast adaptation to cold. Genes whose overexpression improved fermentation activity at 12°C were overexpressed by chromosomal integration into commercial wine yeast QA23. Fermentations in synthetic and natural grape must were carried out by this new set of overexpressing strains. The strains overexpressing OLE1 and DPL1 were able to finish fermentation before commercial wine yeast QA23. Only the OLE1 gene overexpression produced a specific aroma profile in the wines produced with natural grape must.

  18. Functional analysis of lipid metabolism genes in wine yeasts during alcoholic fermentation at low temperature

    Directory of Open Access Journals (Sweden)

    María López-Malo

    2014-10-01

    Full Text Available Wine produced by low-temperature fermentation is mostly considered to have improved sensory qualities. However few commercial wine strains available on the market are well-adapted to ferment at low temperature (10 – 15°C. The lipid metabolism of Saccharomyces cerevisiae plays a central role in low temperature adaptation. One strategy to modify lipid composition is to alter transcriptional activity by deleting or overexpressing the key genes of lipid metabolism. In a previous study, we identified the genes of the phospholipid, sterol and sphingolipid pathways, which impacted on growth capacity at low temperature. In the present study, we aimed to determine the influence of these genes on fermentation performance and growth during low-temperature wine fermentations. We analyzed the phenotype during fermentation at the low and optimal temperature of the lipid mutant and overexpressing strains in the background of a derivative commercial wine strain. The increase in the gene dosage of some of these lipid genes, e.g., PSD1, LCB3, DPL1 and OLE1, improved fermentation activity during low-temperature fermentations, thus confirming their positive role during wine yeast adaptation to cold. Genes whose overexpression improved fermentation activity at 12°C were overexpressed by chromosomal integration into commercial wine yeast QA23. Fermentations in synthetic and natural grape must were carried out by this new set of overexpressing strains. The strains overexpressing OLE1 and DPL1 were able to finish fermentation before commercial wine yeast QA23. Only the OLE1 gene overexpression produced a specific aroma profile in the wines produced with natural grape must.

  19. Yeast population dynamics during prefermentative cold soak of Cabernet Sauvignon and Malbec wines.

    Science.gov (United States)

    Maturano, Y Paola; Mestre, M Victoria; Esteve-Zarzoso, Braulio; Nally, María Cristina; Lerena, María Cecilia; Toro, María Eugenia; Vazquez, Fabio; Combina, Mariana

    2015-04-16

    Prefermentative cold soak is a widely used technique in red wine production, but the impact on the development of native yeast species is hardly described. The aim of this work was to analyse the dynamics and diversity of yeast populations during prefermentative cold soak in red wines. Three different temperatures (14 ± 1 °C; 8 ± 1 °C and 2.5 ± 1 °C) were used for prefermentative cold soak in Cabernet Sauvignon and Malbec grape musts. Saccharomyces and non-Saccharomyces populations during cold soak and alcoholic fermentation were analysed. In addition, the impact on chemical and sensory properties of the wines was examined. Yeast dynamics during prefermentative cold soak were temperature dependent. At 14 ± 1 °C, the total yeast population progressively increased throughout the cold soak period. Conversely, at 2.5 ± 1 °C, the yeast populations maintained stable during the same period. Prefermentative cold soak conducted at 14±1°C favoured development of Hanseniospora uvarum and Candida zemplinina, whereas cold soak conducted at 8 ± 1 °C favoured growth of Saccharomyces cerevisiae. At 2.5 ± 1 °C, no changes in yeast species were recorded. Acidity and bitterness, two sensory descriptors, appear to be related to wines produced with prefermentative cold soak carried out at 14 ± 1 °C. This fact could be associated with the increase in non-Saccharomyces during the prefermentation stage. Our results emphasise the importance of the temperature as a determinant factor to allow an increase in non-Saccharomyces population during prefermentative cold soak and consequently to modify sensorial attributes of wines as well as their sensorial impact. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Transcriptional Regulation and the Diversification of Metabolism in Wine Yeast Strains

    Science.gov (United States)

    Rossouw, Debra; Jacobson, Dan; Bauer, Florian F.

    2012-01-01

    Transcription factors and their binding sites have been proposed as primary targets of evolutionary adaptation because changes to single transcription factors can lead to far-reaching changes in gene expression patterns. Nevertheless, there is very little concrete evidence for such evolutionary changes. Industrial wine yeast strains, of the species Saccharomyces cerevisiae, are a geno- and phenotypically diverse group of organisms that have adapted to the ecological niches of industrial winemaking environments and have been selected to produce specific styles of wine. Variation in transcriptional regulation among wine yeast strains may be responsible for many of the observed differences and specific adaptations to different fermentative conditions in the context of commercial winemaking. We analyzed gene expression profiles of wine yeast strains to assess the impact of transcription factor expression on metabolic networks. The data provide new insights into the molecular basis of variations in gene expression in industrial strains and their consequent effects on metabolic networks important to wine fermentation. We show that the metabolic phenotype of a strain can be shifted in a relatively predictable manner by changing expression levels of individual transcription factors, opening opportunities to modify transcription networks to achieve desirable outcomes. PMID:22042577

  1. Novel Centromeric Loci of the Wine and Beer Yeast Dekkera bruxellensis CEN1 and CEN2

    DEFF Research Database (Denmark)

    Ishchuk, Olena P.; Vojvoda Zeljko, Tanja; Schifferdecker, Anna J.

    2016-01-01

    The wine and beer yeast Dekkera bruxellensis thrives in environments that are harsh and limiting, especially in concentrations with low oxygen and high ethanol. Its different strains' chromosomes greatly vary in number (karyotype). This study isolates two novel centromeric loci (CEN1 and CEN2...

  2. Removal of Brettanomyces bruxellensis from red wine using membrane filtration

    Science.gov (United States)

    While sulfites help limit growth of the spoilage yeast, Brettanomyces, SO2 has been reported to decrease cell size, thereby potentially decreasing the porosities of filtration membranes required for removal. B. bruxellensis strains B1b and F3 were inoculated into red wines and after 12 days, half th...

  3. Volatile flavour profile of reduced alcohol wines fermented with the non-conventional yeast species Metschnikowia pulcherrima and Saccharomyces uvarum.

    Science.gov (United States)

    Varela, C; Sengler, F; Solomon, M; Curtin, C

    2016-10-15

    Production of quality wines with decreased alcohol concentration continues to be one of the major challenges facing wine producers. Therefore, there is considerable interest in the isolation or generation of wine yeasts less efficient at transforming grape sugars into ethanol. We recently demonstrated that Metschnikowia pulcherrima AWRI1149 and Saccharomyces uvarum AWRI2846 were both able to produce reduced alcohol wine when used in sequential inoculation with Saccharomyces cerevisiae. This effect is additive when both strains are co-inoculated in grape must. Here we describe the volatile flavour profile of Chardonnay and Shiraz wines produced with these two strains. Wines fermented with M. pulcherrima showed concentrations of ethyl acetate likely to affect negatively wine aroma. Wines fermented with S. uvarum and with a combination of M. pulcherrima and S. uvarum were characterised by increased concentrations of 2-phenyl ethanol and 2-phenylethyl acetate, both associated with positive sensory attributes. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Growth of non-Saccharomyces yeasts affects nutrient availability for Saccharomyces cerevisiae during wine fermentation.

    Science.gov (United States)

    Medina, Karina; Boido, Eduardo; Dellacassa, Eduardo; Carrau, Francisco

    2012-07-02

    Yeast produces numerous secondary metabolites during fermentation that impact final wine quality. Although it is widely recognized that growth of diverse non-Saccharomyces (NS) yeast can positively affect flavor complexity during Saccharomyces cerevisiae wine fermentation, the inability to control spontaneous or co-fermentation processes by NS yeast has restricted their use in winemaking. We selected two NS yeasts from our Uruguayan native collection to study NS-S. cerevisiae interactions during wine fermentation. The selected strains of Hanseniaspora vineae and Metschnikowia pulcherrima had different yeast assimilable nitrogen consumption profiles and had different effects on S. cerevisiae fermentation and growth kinetics. Studies in which we varied inoculum size and using either simultaneous or sequential inoculation of NS yeast and S. cerevisiae suggested that competition for nutrients had a significant effect on fermentation kinetics. Sluggish fermentations were more pronounced when S. cerevisiae was inoculated 24h after the initial stage of fermentation with a NS strain compared to co-inoculation. Monitoring strain populations using differential WL nutrient agar medium and fermentation kinetics of mixed cultures allowed for a better understanding of strain interactions and nutrient addition effects. Limitation of nutrient availability for S. cerevisiae was shown to result in stuck fermentations as well as to reduce sensory desirability of the resulting wine. Addition of diammonium phosphate (DAP) and a vitamin mix to a defined medium allowed for a comparison of nutrient competition between strains. Addition of DAP and the vitamin mix was most effective in preventing stuck fermentations. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Impact of yeast starter formulations on the production of volatile compounds during wine fermentation.

    Science.gov (United States)

    Romano, Patrizia; Pietrafesa, Rocchina; Romaniello, Rossana; Zambuto, Marianna; Calabretti, Antonella; Capece, Angela

    2015-01-01

    The most diffused starter formulation in winemaking is actually represented by active dry yeast (ADY). Spray-drying has been reported as an appropriate preservation method for yeast and other micro-organisms. Despite the numerous advantages of this method, the high air temperatures used can negatively affect cell viability and the fermentative performance of dried cells. In the present study, 11 wine S. cerevisiae strains (both indigenous and commercial) were submitted to spray-drying; different process conditions were tested in order to select the conditions allowing the highest strain survival. The strains exhibited high variability for tolerance to spray-drying treatment. Selected strains were tested in fermentation at laboratory scale in different formulations (free fresh cells, free dried cells, immobilized fresh cells and immobilized dried cells), in order to assess the influence of starter formulation on fermentative fitness of strains and aromatic quality of wine. The analysis of volatile fraction in the experimental wines produced by selected strains in different formulations allowed identification of > 50 aromatic compounds (alcohols, esters, ketones, aldehydes and terpenes). The results obtained showed that the starter formulation significantly influenced the content of volatile compounds. In particular, the wines obtained by strains in dried forms (as both free and immobilized cells) contained higher numbers of volatile compounds than wines obtained from fresh cells. Copyright © 2014 John Wiley & Sons, Ltd.

  6. Interactions Between Industrial Yeasts and Chemical Contaminants in Grape Juice Affect Wine Composition Profile

    Directory of Open Access Journals (Sweden)

    Etjen Bizaj

    2014-01-01

    Full Text Available The interaction between four industrial wine yeast strains and grape juice chemical contaminants during alcoholic fermentation was studied. Industrial strains of Saccharomyces cerevisiae (AWRI 0838, S. cerevisiae mutant with low H2S production phenotype (AWRI 1640, interspecies hybrid of S. cerevisiae and S. kudriavzevii (AWRI 1539 and a hybrid of AWRI 1640 and AWRI 1539 (AWRI 1810 were exposed separately to fungicides pyrimethanil (Pyr, 10 mg/L and fenhexamid (Fhx, 10 mg/L, as well as to the most common toxin produced by moulds on grapes, ochratoxin A (OTA, 5 μg/L, during alcoholic fermentation of Vitis vinifera L. cv. Sauvignon blanc juice. Contaminants were found to strongly impair fermentation performance and metabolic activity of all yeast strains studied. The chemical profile of wine was analyzed by HPLC (volatile acidity, concentrations of ethanol, fructose, glucose, glycerol and organic acids and the aromatic profile was analyzed using a stable isotope dilution technique using GC/MS (ethyl esters, acetates and aromatic alcohols and Kitagawa tubes (H2S. The chemical composition of wine with added contaminants was in all cases significantly different from the control. Of particular note is that the quantity of aromatic compounds produced by yeast was significantly lower. Yeast’s capacity to remove contaminants from wine at the end of the alcoholic fermentation, and after extended contact (7 days was determined. All the strains were able to remove contaminants from the media, moreover, after extended contact, the concentration of contaminants was in most cases lower.

  7. Yeast strains role on the sulphur dioxyde combinations of wines obtained from noble rot and raisining grapes

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    Isabelle Masneuf-Pomarède

    2000-03-01

    Full Text Available The influence of four industrial and indigenous yeast strains on the sulphur dioxide combinations of wines obtained from noble rot and raisining grapes is studied in different growth of the Sauternes area and one growth in the Jurançon area. The analysis of ketonic compounds (pyruvic acid and 2-oxo-glutaric acid, acetaldehyde and PC50 on the wines clearly showed significant statistical difference between the yeast strains for the sulphur dioxide combination. By adding the same dosage of sulphiting, the free SO2 levels are variable depending on the yeast strain used. One strain (Zymaflore ST, isolated from a spontaneous fermentation of a botrytised must, giving wines with low PC50 values, is well adapted for the noble rot must vinification. The choice of the yeast strain is a parameter of importance to limit the sulphur dioxide amount in the wines.

  8. Analysis of ribosomal RNA stability in dead cells of wine yeast by quantitative PCR.

    Science.gov (United States)

    Sunyer-Figueres, Merce; Wang, Chunxiao; Mas, Albert

    2018-04-02

    During wine production, some yeasts enter a Viable But Not Culturable (VBNC) state, which may influence the quality and stability of the final wine through remnant metabolic activity or by resuscitation. Culture-independent techniques are used for obtaining an accurate estimation of the number of live cells, and quantitative PCR could be the most accurate technique. As a marker of cell viability, rRNA was evaluated by analyzing its stability in dead cells. The species-specific stability of rRNA was tested in Saccharomyces cerevisiae, as well as in three species of non-Saccharomyces yeast (Hanseniaspora uvarum, Torulaspora delbrueckii and Starmerella bacillaris). High temperature and antimicrobial dimethyl dicarbonate (DMDC) treatments were efficient in lysing the yeast cells. rRNA gene and rRNA (as cDNA) were analyzed over 48 h after cell lysis by quantitative PCR. The results confirmed the stability of rRNA for 48 h after the cell lysis treatments. To sum up, rRNA may not be a good marker of cell viability in the wine yeasts that were tested. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Influence of yeast macromolecules on sweetness in dry wines: role of the saccharomyces cerevisiae protein Hsp12.

    Science.gov (United States)

    Marchal, Axel; Marullo, Philippe; Moine, Virginie; Dubourdieu, Denis

    2011-03-09

    Yeast autolysis during lees contact influences the organoleptic properties of wines especially by increasing their sweet taste. Although observed by winemakers, this phenomenon is poorly explained in enology. Moreover, the compounds responsible for sweetness in wine remain unidentified. This work provides new insights in this way by combining sensorial, biochemical and genetic approaches. First, we verified by sensory analysis that yeast autolysis in red wine has a significant effect on sweetness. Moderate additions of ethanol or glycerol did not have the same effect. Second, a sapid fraction was isolated from lees extracts by successive ultrafiltrations and HPLC purifications. Using nano-LC-MS/MS, peptides released by the yeast heat shock protein Hsp12p were distinctly identified in this sample. Third, we confirmed the sweet contribution of this protein by sensorial comparison of red wines incubated with two kinds of yeast strains: a wild-type strain containing the native Hsp12p and a deletion mutant strain that lacks the Hsp12p protein (Δ°HSP12 strain). Red wines incubated with wild-type strain showed a significantly higher sweetness than control wines incubated with Δ°HSP12 strains. These results demonstrated the contribution of protein Hsp12p in the sweet perception consecutive to yeast autolysis in wine.

  10. Impact of glutathione-enriched inactive dry yeast preparations on the stability of terpenes during model wine aging.

    Science.gov (United States)

    Rodríguez-Bencomo, Juan José; Andújar-Ortiz, Inmaculada; Moreno-Arribas, M Victoria; Simó, Carolina; González, Javier; Chana, Antonio; Dávalos, Juan; Pozo-Bayón, M Ángeles

    2014-02-12

    The impact of the addition of glutathione-enriched Inactive dry yeast preparations (g-IDYs) on the stability of some typical wine terpenes (linalool, α-terpineol, β-citronellol, and nerol) stored under accelerated oxidative conditions was evaluated in model wines. Additionally, the effects of a second type of IDY preparation with a different claim (fermentative nutrient) and the sole addition of commercial glutathione into the model wines were also assessed. Model wines were spiked with the low molecular weight fraction (loss of typical wine terpenes in model wines submitted to accelerated aging conditions. The g-IDY preparation did indeed release reduced GSH into the model wines, although this compound did not seem exclusively related to the protective effect on some aroma compounds determined in both model wines. The presence of other sulfur-containing compounds from yeast origin in g-IDY, and also the presence of small yeast peptides, such as methionine/tryptophan/tyrosine-containing tripeptide in both types of IDYs, seemed to be related to the antioxidant activity determined in the two permeates and to the minor loss of some terpenes in the model wines spiked with them.

  11. Yeast Starter as a Biotechnological Tool for Reducing Copper Content in Wine

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    Angela Capece

    2018-01-01

    Full Text Available Copper is widely used in agriculture as a traditional fungicide in organic farming to control downy mildew on grapes, consequently it is possible to find this metal during all stages of the vinification process. Low amounts of copper play a key role on the function of key cell enzymes, whereas excess quantities can exert amount-dependent cytotoxicity, resulting in general cellular damage. Nowadays the excessive copper ions in wines is removed by addition of adsorbents, but these additives can influence the sensory characteristics of wine, as well as detrimental to the health of consumers. It is well known that high concentrations of Cu2+ can be toxic to yeasts, inhibiting growth and activity, causing sluggish fermentation and reducing alcohol production. In this study, 47 S. cerevisiae strains were tested for copper tolerance by two different tests, growth on copper added medium and fermentative activity in copper added grape must. The results obtained by the two different tests were comparable and the high strain variability found was used to select four wild strains, possessing this characteristic at the highest (PP1-13 and A20 and the lowest level (MPR2-24 and A13. The selected strains were tested in synthetic and natural grape must fermentation for ability to reduce copper content in wine. The determination of copper content in wines and yeast cells revealed that at the lowest copper residual in wine corresponded the highest content in yeast cells, indicating a strong strain ability to reduce the copper content in wine. This effect was inversely correlated with strain copper resistance and the most powerful strain in copper reduction was the most sensitive strain, MPR2-24. This wild strain was finally tested as starter culture in cellar pilot scale fermentation in comparison to a commercial starter, confirming the behavior exhibited at lab scale. The use of this wild strain to complete the alcoholic fermentation and remove the copper from

  12. Non-Saccharomyces Yeasts Nitrogen Source Preferences: Impact on Sequential Fermentation and Wine Volatile Compounds Profile

    Science.gov (United States)

    Gobert, Antoine; Tourdot-Maréchal, Raphaëlle; Morge, Christophe; Sparrow, Céline; Liu, Youzhong; Quintanilla-Casas, Beatriz; Vichi, Stefania; Alexandre, Hervé

    2017-01-01

    Nitrogen sources in the must are important for yeast metabolism, growth, and performance, and wine volatile compounds profile. Yeast assimilable nitrogen (YAN) deficiencies in grape must are one of the main causes of stuck and sluggish fermentation. The nitrogen requirement of Saccharomyces cerevisiae metabolism has been described in detail. However, the YAN preferences of non-Saccharomyces yeasts remain unknown despite their increasingly widespread use in winemaking. Furthermore, the impact of nitrogen consumption by non-Saccharomyces yeasts on YAN availability, alcoholic performance and volatile compounds production by S. cerevisiae in sequential fermentation has been little studied. With a view to improving the use of non-Saccharomyces yeasts in winemaking, we studied the use of amino acids and ammonium by three strains of non-Saccharomyces yeasts (Starmerella bacillaris, Metschnikowia pulcherrima, and Pichia membranifaciens) in grape juice. We first determined which nitrogen sources were preferentially used by these yeasts in pure cultures at 28 and 20°C (because few data are available). We then carried out sequential fermentations at 20°C with S. cerevisiae, to assess the impact of the non-Saccharomyces yeasts on the availability of assimilable nitrogen for S. cerevisiae. Finally, 22 volatile compounds were quantified in sequential fermentation and their levels compared with those in pure cultures of S. cerevisiae. We report here, for the first time, that non-Saccharomyces yeasts have specific amino-acid consumption profiles. Histidine, methionine, threonine, and tyrosine were not consumed by S. bacillaris, aspartic acid was assimilated very slowly by M. pulcherrima, and glutamine was not assimilated by P. membranifaciens. By contrast, cysteine appeared to be a preferred nitrogen source for all non-Saccharomyces yeasts. In sequential fermentation, these specific profiles of amino-acid consumption by non-Saccharomyces yeasts may account for some of the

  13. Non-Saccharomyces Yeasts Nitrogen Source Preferences: Impact on Sequential Fermentation and Wine Volatile Compounds Profile

    Directory of Open Access Journals (Sweden)

    Antoine Gobert

    2017-11-01

    Full Text Available Nitrogen sources in the must are important for yeast metabolism, growth, and performance, and wine volatile compounds profile. Yeast assimilable nitrogen (YAN deficiencies in grape must are one of the main causes of stuck and sluggish fermentation. The nitrogen requirement of Saccharomyces cerevisiae metabolism has been described in detail. However, the YAN preferences of non-Saccharomyces yeasts remain unknown despite their increasingly widespread use in winemaking. Furthermore, the impact of nitrogen consumption by non-Saccharomyces yeasts on YAN availability, alcoholic performance and volatile compounds production by S. cerevisiae in sequential fermentation has been little studied. With a view to improving the use of non-Saccharomyces yeasts in winemaking, we studied the use of amino acids and ammonium by three strains of non-Saccharomyces yeasts (Starmerella bacillaris, Metschnikowia pulcherrima, and Pichia membranifaciens in grape juice. We first determined which nitrogen sources were preferentially used by these yeasts in pure cultures at 28 and 20°C (because few data are available. We then carried out sequential fermentations at 20°C with S. cerevisiae, to assess the impact of the non-Saccharomyces yeasts on the availability of assimilable nitrogen for S. cerevisiae. Finally, 22 volatile compounds were quantified in sequential fermentation and their levels compared with those in pure cultures of S. cerevisiae. We report here, for the first time, that non-Saccharomyces yeasts have specific amino-acid consumption profiles. Histidine, methionine, threonine, and tyrosine were not consumed by S. bacillaris, aspartic acid was assimilated very slowly by M. pulcherrima, and glutamine was not assimilated by P. membranifaciens. By contrast, cysteine appeared to be a preferred nitrogen source for all non-Saccharomyces yeasts. In sequential fermentation, these specific profiles of amino-acid consumption by non-Saccharomyces yeasts may account for

  14. Influence of choice of yeasts on volatile fermentation-derived compounds, colour and phenolics composition in Cabernet Sauvignon wine.

    Science.gov (United States)

    Blazquez Rojas, Inmaculada; Smith, Paul A; Bartowsky, Eveline J

    2012-12-01

    Wine colour, phenolics and volatile fermentation-derived composition are the quintessential elements of a red wine. Many viticultural and winemaking factors contribute to wine aroma and colour with choice of yeast strain being a crucial factor. Besides the traditional Saccharomyces species S. cerevisiae, S. bayanus and several Saccharomyces interspecific hybrids are able to ferment grape juice to completion. This study examined the diversity in chemical composition, including phenolics and fermentation-derived volatile compounds, of an Australian Cabernet Sauvignon due to the use of different Saccharomyces strains. Eleven commercially available Saccharomyces strains were used in this study; S. cerevisiae (7), S. bayanus (2) and interspecific Saccharomyces hybrids (2). The eleven Cabernet Sauvignon wines varied greatly in their chemical composition. Nine yeast strains completed alcoholic fermentation in 19 days; S. bayanus AWRI 1375 in 26 days, and S. cerevisiae AWRI 1554 required 32 days. Ethanol concentrations varied in the final wines (12.7-14.2 %). The two S. bayanus strains produced the most distinct wines, with the ability to metabolise malic acid, generate high glycerol concentrations and distinctive phenolic composition. Saccharomyces hybrid AWRI 1501 and S. cerevisiae AWRI 1554 and AWRI 1493 also generated distinctive wines. This work demonstrates that the style of a Cabernet Sauvignon can be clearly modulated by choice of commercially available wine yeast.

  15. The effect of supplementation with three commercial inactive dry yeasts on the colour, phenolic compounds, polysaccharides and astringency of a model wine solution and red wine.

    Science.gov (United States)

    González-Royo, Elena; Esteruelas, Mireia; Kontoudakis, Nikolaos; Fort, Francesca; Canals, Joan Miquel; Zamora, Fernando

    2017-01-01

    Nowadays supplementing red wines with commercial inactive dry yeasts is a widespread practice in winemaking because it leads to better balanced wines through increased mouthfeel and smooth astringency. The aim of this article is to study, in a red wine and in a model wine solution, how supplementation with three commercial inactive dry yeasts affects chemical composition and astringency. This will give us a better understanding of the action mechanism involved. The results suggest that this action mechanism is related to two different phenomena. The first is that inactive yeasts release polysaccharides and oligosaccharides which can increase mouthfeel and inhibit interactions between salivary protein and tannins. The second is that they have a direct effect on the precipitation or absorption of proanthocyanidins, especially the larger polymers, which have been described as the most astringent. It can be concluded that supplementation with inactive yeasts is indeed a useful tool for smoothing the astringency of red wines. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  16. Evaluation of Gene Modification Strategies for the Development of Low-Alcohol-Wine Yeasts

    Science.gov (United States)

    Kutyna, D. R.; Solomon, M. R.; Black, C. A.; Borneman, A.; Henschke, P. A.; Pretorius, I. S.; Chambers, P. J.

    2012-01-01

    Saccharomyces cerevisiae has evolved a highly efficient strategy for energy generation which maximizes ATP energy production from sugar. This adaptation enables efficient energy generation under anaerobic conditions and limits competition from other microorganisms by producing toxic metabolites, such as ethanol and CO2. Yeast fermentative and flavor capacity forms the biotechnological basis of a wide range of alcohol-containing beverages. Largely as a result of consumer demand for improved flavor, the alcohol content of some beverages like wine has increased. However, a global trend has recently emerged toward lowering the ethanol content of alcoholic beverages. One option for decreasing ethanol concentration is to use yeast strains able to divert some carbon away from ethanol production. In the case of wine, we have generated and evaluated a large number of gene modifications that were predicted, or known, to impact ethanol formation. Using the same yeast genetic background, 41 modifications were assessed. Enhancing glycerol production by increasing expression of the glyceraldehyde-3-phosphate dehydrogenase gene, GPD1, was the most efficient strategy to lower ethanol concentration. However, additional modifications were needed to avoid negatively affecting wine quality. Two strains carrying several stable, chromosomally integrated modifications showed significantly lower ethanol production in fermenting grape juice. Strain AWRI2531 was able to decrease ethanol concentrations from 15.6% (vol/vol) to 13.2% (vol/vol), whereas AWRI2532 lowered ethanol content from 15.6% (vol/vol) to 12% (vol/vol) in both Chardonnay and Cabernet Sauvignon juices. Both strains, however, produced high concentrations of acetaldehyde and acetoin, which negatively affect wine flavor. Further modifications of these strains allowed reduction of these metabolites. PMID:22729542

  17. Microbiological diversity and prevalence of spoilage and pathogenic bacteria in commercial fermented alcoholic beverages (beer, fruit wine, refined rice wine, and yakju).

    Science.gov (United States)

    Jeon, Se Hui; Kim, Nam Hee; Shim, Moon Bo; Jeon, Young Wook; Ahn, Ji Hye; Lee, Soon Ho; Hwang, In Gyun; Rhee, Min Suk

    2015-04-01

    The present study examined 469 commercially available fermented alcoholic beverages (FABs), including beer (draft, microbrewed, and pasteurized), fruit wine (grape and others), refined rice wine, and yakju (raw and pasteurized). Samples were screened for Escherichia coli and eight foodborne pathogens (Bacillus cereus, Campylobacter jejuni, Clostridium perfringens, Escherichia coli O157:H7, Listeria monocytogenes, Salmonella spp., Staphylococcus aureus, and Yersinia enterocolitica), and the aerobic plate count, lactic acid bacteria, acetic acid bacteria, fungi, and total coliforms were also enumerated. Microbrewed beer contained the highest number of microorganisms (average aerobic plate count, 3.5; lactic acid bacteria, 2.1; acetic acid bacteria, 2.0; and fungi, 3.6 log CFU/ml), followed by draft beer and yakju (P beer samples) and B. cereus (detected in all FABs) were present in some products. B. cereus was detected most frequently in microbrewed beer (54.8% of samples) and nonpasteurized yakju (50.0%), followed by pasteurized yakju (28.8%), refined rice wine (25.0%), other fruit wines (12.3%), grape wine (8.6%), draft beer (5.6%), and pasteurized beer (2.2%) (P < 0.05). The finding that spore-forming B. cereus and coliform bacteria can survive the harsh conditions present in alcoholic beverages should be taken into account (alongside traditional quality indicators such as the presence of lactic acid-producing bacteria, acetic acid-producing bacteria, or both) when developing manufacturing systems and methods to prolong the shelf life of high-quality FAB products. New strategic quality management plans for various FABs are needed.

  18. Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine

    Directory of Open Access Journals (Sweden)

    Rocío eVelázquez

    2015-11-01

    Full Text Available Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by S. cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii–dominated wines, most of the compounds with fresh fruit odour descriptors, including those with the greatest odour activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate, were more abundant in the S. cerevisiae–dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii–dominated wines the low-relative-concentration compounds with dried fruit and pastry odours. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S

  19. Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine.

    Science.gov (United States)

    Velázquez, Rocío; Zamora, Emiliano; Álvarez, María L; Hernández, Luis M; Ramírez, Manuel

    2015-01-01

    Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by Saccharomyces cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii-dominated wines, most of the compounds with fresh fruit odor descriptors, including those with the greatest odor activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate), were more abundant in the S. cerevisiae-dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii-dominated wines the low-relative-concentration compounds with dried fruit and pastry odors. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S. cerevisiae.

  20. Effects of new Torulaspora delbrueckii killer yeasts on the must fermentation kinetics and aroma compounds of white table wine

    Science.gov (United States)

    Velázquez, Rocío; Zamora, Emiliano; Álvarez, María L.; Hernández, Luis M.; Ramírez, Manuel

    2015-01-01

    Torulaspora delbrueckii is becoming widely recommended for improving some specific characteristics of wines. However, its impact on wine quality is still far from satisfactory at the winery level, mostly because it is easily replaced by Saccharomyces cerevisiae-like yeasts during must fermentation. New T. delbrueckii killer strains were here isolated and selected for winemaking. They killed S. cerevisiae yeasts and were able to dominate and complete the fermentation of sterile grape must. Sequential yeast inoculation of non-sterile white must with T. delbrueckii followed by S. cerevisiae did not ensure T. delbrueckii dominance or wine quality improvement. Only a single initial must inoculation at high cell concentrations allowed the T. delbrueckii killer strains to dominate and complete the must fermentation to reach above 11% ethanol, but not the non-killer strains. None of the wines underwent malolactic fermentation as long as the must had low turbidity and pH. Although no statistically significant differences were found in the wine quality score, the S. cerevisiae-dominated wines were preferred over the T. delbrueckii-dominated ones because the former had high-intensity fresh fruit aromas while the latter had lower intensity, but nevertheless nice and unusual dried fruit/pastry aromas. Except for ethyl propanoate and 3-ethoxy-1-propanol, which were more abundant in the T. delbrueckii–dominated wines, most of the compounds with fresh fruit odor descriptors, including those with the greatest odor activity values (isoamyl acetate, ethyl hexanoate, and ethyl octanoate), were more abundant in the S. cerevisiae–dominated wines. The low relative concentrations of these fruity compounds made it possible to detect in the T. delbrueckii–dominated wines the low-relative-concentration compounds with dried fruit and pastry odors. An example was γ-ethoxy-butyrolactone which was significantly more abundant in these wines than in those dominated by S. cerevisiae. PMID

  1. Influence of different yeast/lactic acid bacteria combinations on the aromatic profile of red Bordeaux wine.

    Science.gov (United States)

    Gammacurta, Marine; Marchand, Stéphanie; Moine, Virginie; de Revel, Gilles

    2017-09-01

    The typical fruity aroma of red Bordeaux wines depends on the grape variety but also on microbiological processes, such as alcoholic and malolactic fermentations. These transformations involve respectively the yeast Saccharomyces cerevisiae and the lactic acid bacterium Oenococcus oeni. Both species play a central role in red winemaking but their quantitative and qualitative contribution to the revelation of the organoleptic qualities of wine has not yet been fully described. The aim of this study was to elucidate the influence of sequential inoculation of different yeast and bacteria strains on the aromatic profile of red Bordeaux wine. All microorganisms completed fermentations and no significant difference was observed between tanks regarding the main oenological parameters until 3 months' aging. Regardless of the yeast strain, B28 bacteria required the shortest period to completely degrade the malic acid, compared to the other strain. Quantification of 73 major components highlighted a specific volatile profile corresponding to each microorganism combination. However, the yeast strain appeared to have a predominant effect on aromatic compound levels, as well as on fruity aroma perception. Yeasts had a greater impact on wine quality and have more influence on the aromatic style of red wine than bacteria. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  2. A Gondwanan Imprint on Global Diversity and Domestication of Wine and Cider Yeast Saccharomyces uvarum

    Science.gov (United States)

    Almeida, Pedro; Gonçalves, Carla; Teixeira, Sara; Libkind, Diego; Bontrager, Martin; Masneuf-Pomarède, Isabelle; Albertin, Warren; Durrens, Pascal; Sherman, David; Marullo, Philippe; Hittinger, Chris Todd; Gonçalves, Paula; Sampaio, José Paulo

    2016-01-01

    In addition to Saccharomyces cerevisiae, the cryotolerant yeast species S. uvarum is also used for wine and cider fermentation but nothing is known about its natural history. Here we use a population genomics approach to investigate its global phylogeography and domestication fingerprints using a collection of isolates obtained from fermented beverages and from natural environments on five continents. South American isolates contain more genetic diversity than that found in the Northern Hemisphere. Moreover, coalescence analyses suggest that a Patagonian sub-population gave rise to the Holarctic population through a recent bottleneck. Holarctic strains display multiple introgressions from other Saccharomyces species, those from S. eubayanus being prevalent in European strains associated with human-driven fermentations. These introgressions are absent in the large majority of wild strains and gene ontology analyses indicate that several gene categories relevant for wine fermentation are overrepresented. Such findings constitute a first indication of domestication in S. uvarum. PMID:24887054

  3. Use of a flor velum yeast for modulating colour, ethanol and major aroma compound contents in red wine.

    Science.gov (United States)

    Moreno, Juan; Moreno-García, Jaime; López-Muñoz, Beatriz; Mauricio, Juan Carlos; García-Martínez, Teresa

    2016-12-15

    The most important and negative effect of the global warming for winemakers in warm and sunny regions is the observed lag between industrial and phenolic grape ripeness, so only it is possible to obtain an acceptable colour when the ethanol content of wine is high. By contrast, the actual market trends are to low ethanol content wines. Flor yeast growing a short time under velum conditions, decreases the ethanol and volatile acidity contents, has a favorable effect on the colour and astringency and significantly changes the wine content in 1-propanol, isobutanol, acetaldehyde, 1,1-diethoxiethane and ethyl lactate. The Principal Component Analysis of six enological parameters or five aroma compounds allows to classify the wines subjected to different velum formation conditions. The obtained results in two tasting sessions suggest that the flor yeast helps to modulate the ethanol, astringency and colour and supports a new biotechnological perspective for red winemakers. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The effect of inactivated yeast-based products on the process of wine aging, phenolic compounds and sensory characteristics of red wine Prokupac

    Directory of Open Access Journals (Sweden)

    Malićanin Marko

    2017-01-01

    Full Text Available Keeping of red wine in bottles is very important for its maturation and quality. However, there are numerous changes that happen during that period, usually caused by oxidative processes and changes in structure and content of polyphenolic compounds. The goal of this study was to determine the effects of Inactivated dry yeast (IDY products on aging, phenolics content, colour stability and sensory characteristics of red wine Prokupac (Serbian autochthonous variety. The treatment of wine was done by 3 different IDYP (Lallemand, Canada: Optimum White, Opti Less and Noblesse, applied as 0.2 g/L and 0.4 g /L during 15 days. Subsequently, wine clarification was done, followed by filtration and bottling. Untreated wines were used for comparison. Wine was subjected to accelerated aging (10 days at 55 ° C and also to normal aging conditions during one year. To determine the influence of IDYP following parameters were monitored: dissolved O2, free and total SO2, sugar free extract, content of total phenolics, flavonoids, flavan-3-ols and anthocyanins, percent of polymeric color, color tint, color intensity and sensory characteristics (Panel method. The obtained results clearly show that IDY products are good scavengers of oxygen and have a positive impact on wine quality preservation and its organoleptic characteristics. However, a slight decrease of polyphenols content was detected.

  5. Selected non-Saccharomyces wine yeasts in controlled multistarter fermentations with Saccharomyces cerevisiae on alcoholic fermentation behaviour and wine aroma of cherry wines.

    Science.gov (United States)

    Sun, Shu Yang; Gong, Han Sheng; Jiang, Xiao Man; Zhao, Yu Ping

    2014-12-01

    This study examined the effect of mixed fermentation of non-Saccharomyces (Torulaspora delbrueckii ZYMAFLORE Alpha(TD n. Sacch) and Metschnikowia pulcherrima JS22) and Saccharomyces cerevisiae yeasts (D254 and EC1118) on the production of cherry wines, in comparison with commonly used mono-culture. Results obtained during AF demonstrated that negligible inhibitory effect was observed in S. cerevisiae/Alpha pair, whereas a strong antagonistic effect was detected between MJS22 and S. cerevisiae strain, resulting in an early death of MJS22. For volatile components determined, S. cerevisiae/MJS22 couple was found to significantly boost the production of most detected compounds, more particularly in higher alcohols, esters, acids and terpenes; while the characteristic of S. cerevisiae/Alpha pair is an increase in fruity esters, higher alcohols and decrease in acid production. Sensory evaluation revealed that S. cerevisiae/MJS22 pair reinforced sweet, green and fatty notes to the cherry wines, and S. cerevisiae/Alpha trial enhanced the fruity odour and reduced green note. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Use of two osmoethanol tolerant yeast strain to ferment must from Tempranillo dried grapes: effect on wine composition.

    Science.gov (United States)

    López de Lerma, N; Peinado, R A

    2011-01-31

    The must from Tempranillo dried grapes was divided into four batches to produce sweet wine. The first one was fortified with ethanol up to 12% (v/v) to avoid fermentation (traditional way). Other two batches were partially fermented with two osmoethanol tolerant Saccharomyces cerevisiae strains (X4 and X5). The last one was fermented with native yeast by spontaneous fermentation. Wines fermented partially with the strains X4 and X5 show high volatile acidity values (above 2g/L expressed as acetic acid), and a glycerol concentration around 20 g/L. Both strains also produce high amount of carboxylic acids and therefore the wines show a high ethyl ester concentration. Aromatic series were obtained for all the wines by grouping aroma compounds according to their odor descriptors. The series of the fermented wines with higher values in relation with the control wine were fruity, sweet and fatty, emphasizing the fruity series in the samples fermented with the X4 and X5 strains. The sensorial analysis of the wine samples by a tasting panel put in evidence that the musts fermented with the osmoethanol tolerant yeasts were better valued than the rest of the wine samples. The must fermented with the X4 strain obtained the maximum score in terms of aroma and flavour. So, the use of these osmoethanol tolerant S. cerevisiae strains could be a suitable alternative to produce sweet wines from must with high sugar concentration. The wines obtained this way are chemically and organoleptically more complex than those elaborated traditionally. Copyright © 2010 Elsevier B.V. All rights reserved.

  7. Whole-Genome Analysis of Three Yeast Strains Used for Production of Sherry-Like Wines Revealed Genetic Traits Specific to Flor Yeasts

    Science.gov (United States)

    Eldarov, Mikhail A.; Beletsky, Alexey V.; Tanashchuk, Tatiana N.; Kishkovskaya, Svetlana A.; Ravin, Nikolai V.; Mardanov, Andrey V.

    2018-01-01

    Flor yeast strains represent a specialized group of Saccharomyces cerevisiae yeasts used for biological wine aging. We have sequenced the genomes of three flor strains originated from different geographic regions and used for production of sherry-like wines in Russia. According to the obtained phylogeny of 118 yeast strains, flor strains form very tight cluster adjacent to the main wine clade. SNP analysis versus available genomes of wine and flor strains revealed 2,270 genetic variants in 1,337 loci specific to flor strains. Gene ontology analysis in combination with gene content evaluation revealed a complex landscape of possibly adaptive genetic changes in flor yeast, related to genes associated with cell morphology, mitotic cell cycle, ion homeostasis, DNA repair, carbohydrate metabolism, lipid metabolism, and cell wall biogenesis. Pangenomic analysis discovered the presence of several well-known “non-reference” loci of potential industrial importance. Events of gene loss included deletions of asparaginase genes, maltose utilization locus, and FRE-FIT locus involved in iron transport. The latter in combination with a flor-yeast-specific mutation in the Aft1 transcription factor gene is likely to be responsible for the discovered phenotype of increased iron sensitivity and improved iron uptake of analyzed strains. Expansion of the coding region of the FLO11 flocullin gene and alteration of the balance between members of the FLO gene family are likely to positively affect the well-known propensity of flor strains for velum formation. Our study provides new insights in the nature of genetic variation in flor yeast strains and demonstrates that different adaptive properties of flor yeast strains could have evolved through different mechanisms of genetic variation. PMID:29867869

  8. Herbicide glufosinate inhibits yeast growth and extends longevity during wine fermentation.

    Science.gov (United States)

    Vallejo, Beatriz; Picazo, Cecilia; Orozco, Helena; Matallana, Emilia; Aranda, Agustín

    2017-09-29

    Glufosinate ammonium (GA) is a widely used herbicide that inhibits glutamine synthetase. This inhibition leads to internal amino acid starvation which, in turn, causes the activation of different nutrient sensing pathways. GA also inhibits the enzyme of the yeast Saccharomyces cerevisiae in such a way that, although it is not used as a fungicide, it may alter yeast performance in industrial processes like winemaking. We describe herein how GA indeed inhibits the yeast growth of a wine strain during the fermentation of grape juice. In turn, GA extends longevity in a variety of growth media. The biochemical analysis indicates that GA partially inhibits the nutrient sensing TORC1 pathway, which may explain these phenotypes. The GCN2 kinase mutant is hypersensitive to GA. Hence the control of translation and amino acid biosynthesis is required to also deal with the damaging effects of this pesticide. A global metabolomics analysis under winemaking conditions indicated that an increase in amino acid and in polyamines occurred. In conclusion, GA affects many different biochemical processes during winemaking, which provides us with some insights into both the effect of this herbicide on yeast physiology and into the relevance of the metabolic step for connecting nitrogen and carbon metabolism.

  9. Selection of non-Saccharomyces yeast strains for reducing alcohol levels in wine by sugar respiration.

    Science.gov (United States)

    Quirós, Manuel; Rojas, Virginia; Gonzalez, Ramon; Morales, Pilar

    2014-07-02

    Respiration of sugars by non-Saccharomyces yeasts has been recently proposed for lowering alcohol levels in wine. Development of industrial fermentation processes based on such an approach requires, amongst other steps, the identification of yeast strains which are able to grow and respire under the relatively harsh conditions found in grape must. This work describes the characterization of a collection of non-Saccharomyces yeast strains in order to identify candidate yeast strains for this specific application. It involved the estimation of respiratory quotient (RQ) values under aerated conditions, at low pH and high sugar concentrations, calculation of yields of ethanol and other relevant metabolites, and characterization of growth responses to the main stress factors found during the first stages of alcoholic fermentation. Physiological features of some strains of Metschnikowia pulcherrima or two species of Kluyveromyces, suggest they are suitable for lowering ethanol yields by respiration. The unsuitability of Saccharomyces cerevisiae strains for this purpose was not due to ethanol yields (under aerated conditions they are low enough for a significant reduction in final ethanol content), but to the high acetic acid yields under these growth conditions. According to results from controlled aeration fermentations with one strain of M. pulcherrima, design of an aeration regime allowing for lowering ethanol yields though preserving grape must components from excessive oxidation, would be conceivable. Copyright © 2014. Published by Elsevier B.V.

  10. Effect of Precursors on Volatile Compounds in Papaya Wine Fermented by Mixed Yeasts

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    Pin-Rou Lee

    2013-01-01

    Full Text Available The impact of the addition of fusel oil or amino acids on the volatile compounds in papaya wine fermented with a mixed culture of Saccharomyces cerevisiae var. bayanus R2 and Williopsis saturnus var. mrakii NCYC 2251 at a ratio of 1:1000 was studied. Fusel oil addition increased the fraction of alcohols and promoted the production of isoamyl octanoate, isoamyl decanoate and isobutyl decanoate, while decreased the fraction of ethyl acetate and 2-phenylethyl acetate. The addition of amino acids enhanced the formation of total volatile fatty acids, 2-phenylethanol and some ethyl esters. The papaya wine with added amino acids possessed more acidic and buttery notes than the control, while that with added fusel oil had an overall aroma profile comparable to that of the control. This study suggests that papaya juice fermentation with mixed yeasts in conjunction with the added fusel oil or selected amino acids may be another method of modulating the flavour of papaya wine.

  11. The effect of increased yeast alcohol acetyltransferase and esterase activity on the flavour profiles of wine and distillates.

    Science.gov (United States)

    Lilly, Mariska; Bauer, Florian F; Lambrechts, Marius G; Swiegers, Jan H; Cozzolino, Daniel; Pretorius, Isak S

    2006-07-15

    The fruity odours of wine are largely derived from the synthesis of esters and higher alcohols during yeast fermentation. The ATF1- and ATF2-encoded alcohol acetyltransferases of S. cerevisiae are responsible for the synthesis of ethyl acetate and isoamyl acetate esters, while the EHT1-encoded ethanol hexanoyl transferase is responsible for synthesizing ethyl caproate. However, esters such as these might be degraded by the IAH1-encoded esterase. The objectives of this study were: (a) to overexpress the genes encoding ester-synthesizing and ester-degrading enzymes in wine yeast; (b) to prepare Colombard table wines and base wines for distillation using these modified strains; and (c) to analyse and compare the ester concentrations and aroma profiles of these wines and distillates. The overexpression of ATF1 significantly increased the concentrations of ethyl acetate, isoamyl acetate, 2-phenylethyl acetate and ethyl caproate, while the overexpression of ATF2 affected the concentrations of ethyl acetate and isoamyl acetate to a lesser degree. The overexpression of IAH1 resulted in a significant decrease in ethyl acetate, isoamyl acetate, hexyl acetate and 2-phenylethyl acetate. The overexpression of EHT1 resulted in a marked increase in ethyl caproate, ethyl caprylate and ethyl caprate. The flavour profile of the wines and distillates prepared using the modified strains were also significantly altered as indicated by formal sensory analysis. This study offers prospects for the development of wine yeast starter strains with optimized ester-producing capability that could assist winemakers in their effort to consistently produce wine and distillates such as brandy to definable flavour specifications and styles.

  12. Raspberry wine fermentation with suspended and immobilized yeast cells of two strains of Saccharomyces cerevisiae.

    Science.gov (United States)

    Djordjević, Radovan; Gibson, Brian; Sandell, Mari; de Billerbeck, Gustavo M; Bugarski, Branko; Leskošek-Čukalović, Ida; Vunduk, Jovana; Nikićević, Ninoslav; Nedović, Viktor

    2015-01-01

    The objectives of this study were to assess the differences in fermentative behaviour of two different strains of Saccharomyces cerevisiae (EC1118 and RC212) and to determine the differences in composition and sensory properties of raspberry wines fermented with immobilized and suspended yeast cells of both strains at 15 °C. Analyses of aroma compounds, glycerol, acetic acid and ethanol, as well as the kinetics of fermentation and a sensory evaluation of the wines, were performed. All fermentations with immobilized yeast cells had a shorter lag phase and faster utilization of sugars and ethanol production than those fermented with suspended cells. Slower fermentation kinetics were observed in all the samples that were fermented with strain RC212 (suspended and immobilized) than in samples fermented with strain EC1118. Significantly higher amounts of acetic acid were detected in all samples fermented with strain RC212 than in those fermented with strain EC1118 (0.282 and 0.602 g/l, respectively). Slightly higher amounts of glycerol were observed in samples fermented with strain EC1118 than in those fermented with strain RC212. Copyright © 2014 John Wiley & Sons, Ltd.

  13. Evaluation of different co-inoculation time of non-Saccharomyces/Saccharomyces yeasts in order to obtain reduced ethanol wines

    Directory of Open Access Journals (Sweden)

    Mestre María Victoria

    2016-01-01

    Full Text Available Decreasing ethanol content in wines has become one of the main objectives of winemakers in different areas of the world. The use of selected wine yeasts can be considered one of the most effective and simple tools. The aim of this study was to evaluate the effect of co-inoculation times of selected non-Saccharomyces/Saccharomyces yeasts on the reduction of ethanol levels in wines. Hanseniaspora uvarum BHu9, Starmerella bacillaris BSb55 and Candida membranaefasciens BCm71 were co-inoculate with Saccharomyces cerevisiae under fermentative conditions. Treatments assayed were: pure fermentations of S. cerevisiae BSc203 and non-Saccharomyces yeasts BHu9, BSb55 and BCm71; -co-fermentations: A-BHu9/BSc203; B-BSb55/BSc203 and C-BCm71/BSc203. These co-inoculations were carried out under mixed (simultaneous inoculation, and sequential conditions (non-Saccharomyces yeasts inoculated at initial time and S. cerevisiae at 48, 96 and 144 h. Lower fermentative efficiencies were registered when BHu9 and BSb55 remained pure more time. Conversely, the conversion efficiency was reduced in co-inocula of BCm71/BSc203, when both yeasts interact more time. Metabolites produced during all vinification processes were within acceptable concentration ranges according to the current legislations. Conclusion Time interaction during fermentation processes of non-Saccharomyces and Saccharomyces yeasts showed influence on ethanol production, and this effect would be dependent on the co-inoculated species.

  14. Influence of the use of selected and non-selected yeasts in red wine production

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    Daniela Dorneles

    2005-09-01

    Full Text Available The aim of this work was to study the influence of use of Saccharomyces cerevisiae selected varieties in the elaboration of Terci red wine from Colombo. The winemaking method followed the classic red wine vinification system and the samples were analyzed according to the official table wine methods. The assays performed showed differences mainly over volatile acids, acetaldehyde, esters and methanol contents, confirming that the use of selected yeasts contributed on improving the wine quality.Dentre os diferentes tipos de vinho, o vinho proveniente de Vitis labrusca ainda é o mais consumido no Brasil. Seu preparo em pequenas vinícolas envolve antigas tradições que acarretam características indesejáveis e imprevisíveis à bebida. Em Colombo (Paraná, Brasil são cultivados anualmente 130 hectares de videiras, produzindo 1300 toneladas de uvas comuns do gênero Vitis labrusca e 800.000 L/ano de vinho artesanal de mesa, sem nenhum procedimento padronizado, como o uso de leveduras selvagens. O objetivo deste trabalho foi estudar a influência do uso de variedades selecionadas de Saccharomyces cerevisiae na elaboração de vinho tinto com uva Terci, proveniente do município de Colombo. A técnica de preparo dos vinhos seguiu o sistema clássico de vinificação para vinhos tintos e as amostras foram analisadas de acordo com os métodos oficiais. Os resultados demonstraram diferenças nas amostras, principalmente em relação aos teores de acidez volátil, acetaldeído, ésteres e metanol, comprovando que com a utilização de leveduras selecionadas contribui para melhorar os parâmetros de qualidade e padronização do vinho.

  15. Yeast-yeast interactions revealed by aromatic profile analysis of Sauvignon Blanc wine fermented by single or co-culture of non-Saccharomyces and Saccharomyces yeasts.

    Science.gov (United States)

    Sadoudi, Mohand; Tourdot-Maréchal, Raphaëlle; Rousseaux, Sandrine; Steyer, Damien; Gallardo-Chacón, Joan-Josep; Ballester, Jordi; Vichi, Stefania; Guérin-Schneider, Rémi; Caixach, Josep; Alexandre, Hervé

    2012-12-01

    There has been increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. The main reason is that the multistarter fermentation process is thought to simulate indigenous fermentation, thus increasing wine aroma complexity while avoiding the risks linked to natural fermentation. However, multistarter fermentation is characterised by complex and largely unknown interactions between yeasts. Consequently the resulting wine quality is rather unpredictable. In order to better understand the interactions that take place between non-Saccharomyces and Saccharomyces yeasts during alcoholic fermentation, we analysed the volatile profiles of several mono-culture and co-cultures. Candida zemplinina, Torulaspora delbrueckii and Metschnikowia pulcherrima were used to conduct fermentations either in mono-culture or in co-culture with S. cerevisiae. Up to 48 volatile compounds belonging to different chemical families were quantified. For the first time, we show that C. zemplinina is a strong producer of terpenes and lactones. We demonstrate by means of multivariate analysis that different interactions exist between the co-cultures studied. We observed a synergistic effect on aromatic compound production when M. pulcherrima was in co-culture with S. cerevisiae. However a negative interaction was observed between C. zemplinina and S. cerevisiae, which resulted in a decrease in terpene and lactone content. These interactions are independent of biomass production. The aromatic profiles of T. delbrueckii and S. cerevisiae in mono-culture and in co-culture are very close, and are biomass-dependent, reflecting a neutral interaction. This study reveals that a whole family of compounds could be altered by such interactions. These results suggest that the entire metabolic pathway is affected by these interactions. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Polyphenolic and aroma profile of Vranec wines fermented with isolated yeasts from Tikveš wine area

    OpenAIRE

    Ivanova, Violeta; Mitrev, Sasa; Karov, Ilija; Dimovska, Violeta; Ilieva, Fidanka; Balabanova, Biljana; Kovacevik, Biljana

    2013-01-01

    Wine contains a number of polyphenolic constituents classified as flavonoids and non-flavonoids that play a major role in enology. They contribute to wine sensory characteristics, especially colour, flavor and astringency and therefore, to the differences between red and white wines. On the other hand, wine aroma is a one of its most important characteristics produced by a complex balance of different groups of volatile compounds, belonging to alcohols, esters, aldehydes, lactones, terpenes, ...

  17. Interactions of grape tannins and wine polyphenols with a yeast protein extract, mannoproteins and β-glucan.

    Science.gov (United States)

    Mekoue Nguela, J; Poncet-Legrand, C; Sieczkowski, N; Vernhet, A

    2016-11-01

    At present, there is a great interest in enology for yeast derived products to replace aging on lees in winemaking or as an alternative for wine fining. These are yeast protein extracts (YPE), cell walls and mannoproteins. Our aim was to further understand the mechanisms that drive interactions between these components and red wine polyphenols. To this end, interactions between grape skin tannins or wine polyphenols or tannins and a YPE, a mannoprotein fraction and a β-glucan were monitored by binding experiments, ITC and DLS. Depending on the tannin structure, a different affinity between the polyphenols and the YPE was observed, as well as differences in the stability of the aggregates. This was attributed to the mean degree of polymerization of tannins in the polyphenol fractions and to chemical changes that occur during winemaking. Much lower affinities were found between polyphenols and polysaccharides, with different behaviors between mannoproteins and β-glucans. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Inactivation of Spoilage Yeasts by Mentha spicata L. and M. × villosa Huds. Essential Oils in Cashew, Guava, Mango, and Pineapple Juices

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    Erika T. da Cruz Almeida

    2018-05-01

    Full Text Available This study evaluated the efficacy of the essential oil from Mentha spicata L. (MSEO and M. × villosa Huds. (MVEO to inactivate Candida albicans, C. tropicalis, Pichia anomala and Saccharomyces cerevisiae in Sabouraud dextrose broth and cashew, guava, mango, and pineapple juices during 72 h of refrigerated storage. The effects of the incorporation of an anti-yeast effective dose of MSEO on some physicochemical and sensory characteristics of juices were evaluated. The incorporation of 3.75 μL/mL MSEO or 15 μL/mL MVEO caused a ≥5-log reductions in counts of C. albicans, P. anomala, and S. cerevisiae in Sabouraud dextrose broth. In cashew and guava juices, 1.875 μL/mL MSEO or 15 μL/mL MVEO caused ≥5-log reductions in counts of P. anomala and S. cerevisiae. In pineapple juice, 3.75 μL/mL MSEO caused ≥5-log reductions in counts of P. anomala and S. cerevisiae; 15 μL/mL MVEO caused ≥5-log reductions in counts of S. cerevisiae in mango juice. The incorporation of 1.875 μL/mL MSEO did not affect the physicochemical parameters of juices and did not induce negative impacts to cause their possible sensory rejection. These results show the potential of MSEO and MVEO, primarily MSEO, to comprise strategies to control spoilage yeasts in fruit juices.

  19. Proteomic evolution of a wine yeast during the first hours of fermentation.

    Science.gov (United States)

    Salvadó, Zoel; Chiva, Rosana; Rodríguez-Vargas, Sonia; Rández-Gil, Francisca; Mas, Albert; Guillamón, José Manuel

    2008-11-01

    The inoculation of active dry wine yeast (ADWY) is one of the most common practices in winemaking. This inoculation exposes the yeast cells to strong osmotic, acidic and thermal stresses, and adaptation to the new medium is crucial for successful fermentation. We have analysed the changes that occur in the ADWY protein profile in the first hours after inoculation under enological-like conditions at a low temperature. Protein changes mainly included enzymes of the nitrogen and carbon metabolism and proteins related to the cellular stress response. Most of the enzymes of the lower part of the glycolysis showed an increase in their concentration 4 and 24 h after inoculation, indicating an increase in glycolytic flux and in ATP production. However, the shift from respiration to fermentation was not immediate in the inoculation because some mitochondrial proteins involved in oxidative metabolism were induced in the first hours after inoculation. Inoculation in this fresh medium also reduced the cellular concentration of stress proteins produced during industrial production of the ADWY. The only exception was Cys3p, which might be involved in glutathione synthesis as a response to oxidative stress. A better understanding of the yeast stress response to rehydration and inoculation will lead to improvements in the handling efficiency of ADWY in winemaking and presumably to better control of fermentation startup.

  20. The use of lactic acid-producing, malic acid-producing, or malic acid-degrading yeast strains for acidity adjustment in the wine industry.

    Science.gov (United States)

    Su, Jing; Wang, Tao; Wang, Yun; Li, Ying-Ying; Li, Hua

    2014-03-01

    In an era of economic globalization, the competition among wine businesses is likely to get tougher. Biotechnological innovation permeates the entire world and intensifies the severity of the competition of the wine industry. Moreover, modern consumers preferred individualized, tailored, and healthy and top quality wine products. Consequently, these two facts induce large gaps between wine production and wine consumption. Market-orientated yeast strains are presently being selected or developed for enhancing the core competitiveness of wine enterprises. Reasonable biological acidity is critical to warrant a high-quality wine. Many wild-type acidity adjustment yeast strains have been selected all over the world. Moreover, mutation breeding, metabolic engineering, genetic engineering, and protoplast fusion methods are used to construct new acidity adjustment yeast strains to meet the demands of the market. In this paper, strategies and concepts for strain selection or improvement methods were discussed, and many examples based upon selected studies involving acidity adjustment yeast strains were reviewed. Furthermore, the development of acidity adjustment yeast strains with minimized resource inputs, improved fermentation, and enological capabilities for an environmentally friendly production of healthy, top quality wine is presented.

  1. Aromatic Amino Acid-Derived Compounds Induce Morphological Changes and Modulate the Cell Growth of Wine Yeast Species.

    Science.gov (United States)

    González, Beatriz; Vázquez, Jennifer; Cullen, Paul J; Mas, Albert; Beltran, Gemma; Torija, María-Jesús

    2018-01-01

    Yeasts secrete a large diversity of compounds during alcoholic fermentation, which affect growth rates and developmental processes, like filamentous growth. Several compounds are produced during aromatic amino acid metabolism, including aromatic alcohols, serotonin, melatonin, and tryptamine. We evaluated the effects of these compounds on growth parameters in 16 different wine yeasts, including non- Saccharomyces wine strains, for which the effects of these compounds have not been well-defined. Serotonin, tryptamine, and tryptophol negatively influenced yeast growth, whereas phenylethanol and tyrosol specifically affected non- Saccharomyces strains. The effects of the aromatic alcohols were observed at concentrations commonly found in wines, suggesting a possible role in microbial interaction during wine fermentation. Additionally, we demonstrated that aromatic alcohols and ethanol are able to affect invasive and pseudohyphal growth in a manner dependent on nutrient availability. Some of these compounds showed strain-specific effects. These findings add to the understanding of the fermentation process and illustrate the diversity of metabolic communication that may occur among related species during metabolic processes.

  2. Nitrogen requirements of commercial wine yeast strains during fermentation of a synthetic grape must.

    Science.gov (United States)

    Gutiérrez, Alicia; Chiva, Rosana; Sancho, Marta; Beltran, Gemma; Arroyo-López, Francisco Noé; Guillamon, José Manuel

    2012-08-01

    Nitrogen deficiencies in grape musts are one of the main causes of stuck or sluggish wine fermentations. Currently, the most common method for dealing with nitrogen-deficient fermentations is adding supplementary nitrogen (usually ammonium phosphate). However, it is important to know the specific nitrogen requirement of each strain, to avoid excessive addition that can lead to microbial instability and ethyl carbamate accumulation. In this study, we aimed to determine the effect of increasing nitrogen concentrations of three different nitrogen sources on growth and fermentation performance in four industrial wine yeast strains. This task was carried out using statistical modeling techniques. The strains PDM and RVA showed higher growth-rate and maximum population size and consumed nitrogen much more quickly than strains ARM and TTA. Likewise, the strains PDM and RVA were also the greatest nitrogen demanders. Thus, we can conclude that these differences in nitrogen demand positively correlated with higher growth rate and higher nitrogen uptake rate. The most direct effect of employing an adequate nitrogen concentration is the increase in biomass, which involves a higher fermentation rate. However, the impact of nitrogen on fermentation rate is not exclusively due to the increase in biomass because the strain TTA, which showed the worst growth behavior, had the best fermentation activity. Some strains may adapt a strategy whereby fewer cells with higher metabolic activity are produced. Regarding the nitrogen source used, all the strains showed the better and worse fermentation performance with arginine and ammonium, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Key role of lipid management in nitrogen and aroma metabolism in an evolved wine yeast strain.

    Science.gov (United States)

    Rollero, Stéphanie; Mouret, Jean-Roch; Sanchez, Isabelle; Camarasa, Carole; Ortiz-Julien, Anne; Sablayrolles, Jean-Marie; Dequin, Sylvie

    2016-02-09

    Fermentative aromas play a key role in the organoleptic profile of young wines. Their production depends both on yeast strain and fermentation conditions. A present-day trend in the wine industry consists in developing new strains with aromatic properties using adaptive evolution approaches. An evolved strain, Affinity™ ECA5, overproducing esters, was recently obtained. In this study, dynamics of nitrogen consumption and of the fermentative aroma synthesis of the evolved and its ancestral strains were compared and coupled with a transcriptomic analysis approach to better understand the metabolic reshaping of Affinity™ ECA5. Nitrogen assimilation was different between the two strains, particularly amino acids transported by carriers regulated by nitrogen catabolite repression. We also observed differences in the kinetics of fermentative aroma production, especially in the bioconversion of higher alcohols into acetate esters. Finally, transcriptomic data showed that the enhanced bioconversion into acetate esters by the evolved strain was associated with the repression of genes involved in sterol biosynthesis rather than an enhanced expression of ATF1 and ATF2 (genes coding for the enzymes responsible for the synthesis of acetate esters from higher alcohols). An integrated approach to yeast metabolism-combining transcriptomic analyses and online monitoring data-showed differences between the two strains at different levels. Differences in nitrogen source consumption were observed suggesting modifications of NCR in the evolved strain. Moreover, the evolved strain showed a different way of managing the lipid source, which notably affected the production of acetate esters, likely because of a greater availability of acetyl-CoA for the evolved strain.

  4. Non-canonical regulation of glutathione and trehalose biosynthesis characterizes non-Saccharomyces wine yeasts with poor performance in active dry yeast production

    Directory of Open Access Journals (Sweden)

    Esther Gamero-Sandemetrio

    2018-01-01

    Full Text Available Several yeast species, belonging to Saccharomyces and non-Saccharomyces genera, play fundamental roles during spontaneous must grape fermentation, and recent studies have shown that mixed fermentations, co-inoculated with S. cerevisiae and non-Saccharomyces strains, can improve wine organoleptic properties. During active dry yeast (ADY production, antioxidant systems play an essential role in yeast survival and vitality as both biomass propagation and dehydration cause cellular oxidative stress and negatively affect technological performance. Mechanisms for adaptation and resistance to desiccation have been described for S. cerevisiae, but no data are available on the physiology and oxidative stress response of non-Saccharomyces wine yeasts and their potential impact on ADY production. In this study we analyzed the oxidative stress response in several non-Saccharomyces yeast species by measuring the activity of reactive oxygen species (ROS scavenging enzymes, e.g., catalase and glutathione reductase, accumulation of protective metabolites, e.g., trehalose and reduced glutathione (GSH, and lipid and protein oxidation levels. Our data suggest that non-canonical regulation of glutathione and trehalose biosynthesis could cause poor fermentative performance after ADY production, as it corroborates the corrective effect of antioxidant treatments, during biomass propagation, with both pure chemicals and food-grade argan oil.

  5. Yeast ratio is a critical factor for sequential fermentation of papaya wine by Williopsis saturnus and Saccharomyces cerevisiae.

    Science.gov (United States)

    Lee, Pin-Rou; Kho, Stephanie Hui Chern; Yu, Bin; Curran, Philip; Liu, Shao-Quan

    2013-07-01

    The growth kinetics and fermentation performance of Williopsis saturnus and Saccharomyces cerevisiae at ratios of 10:1, 1:1 and 1:10 (W.:S.) were studied in papaya juice with initial 7-day fermentation by W.saturnus, followed by S. cerevisiae. The growth kinetics of W. saturnus were similar at all ratios, but its maximum cell count decreased as the proportion of S. cerevisiae was increased. Conversely, there was an early death of S. cerevisiae at the ratio of 10:1. Williopsis saturnus was the dominant yeast at 10:1 ratio that produced papaya wine with elevated concentrations of acetate esters. On the other hand, 1:1 and 1:10 ratios allowed the coexistence of both yeasts which enabled the flavour-enhancing potential of W.saturnus as well as the ethyl ester and alcohol-producing abilities of S. cerevisiae. In particular, 1:1 and 1:10 ratios resulted in production of more ethyl esters, alcohols and 2-phenylethyl acetate. However, the persistence of both yeasts at 1:1 and 1:10 ratios led to formation of high levels of acetic acid. The findings suggest that yeast ratio is a critical factor for sequential fermentation of papaya wine by W.saturnus and S. cerevisiae as a strategy to modulate papaya wine flavour. © 2012 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  6. SELECTION AND USE OF YEAST STRAINS ISOLATED FROM AUTOCHTHONOUS SOUTHERN ITALY GRAPEWINE CULTIVARS AND IMPACT ON AROMA PROFILE OF PRODUCED WINES

    OpenAIRE

    Boscaino, Floriana

    2015-01-01

    Today, the use of selected commercial yeasts (LSA) from Saccharomyces species "sensu stricto" is widespread, because it allows to minimize risks in the production process, to standardize the winemaking procedure and ensure the quality of the final product. On the other hand, the widespread use of starter cultures in the wine industry has resulted in a loss of wine sensory characteristics and in a flattening of those differences crucial to distinguish wines of different cultivars. For this ...

  7. Two Decades of “Horse Sweat” Taint and Brettanomyces Yeasts in Wine: Where do We Stand Now?

    Directory of Open Access Journals (Sweden)

    Manuel Malfeito-Ferreira

    2018-04-01

    Full Text Available The unwanted modification of wine sensory attributes by yeasts of the species Brettanomyces bruxellensis due to the production of volatile phenols is presently the main microbiological threat to red wine quality. The effects of ethylphenols and other metabolites on wine flavor is now recognized worldwide and the object of lively debate. The focus of this review is to provide an update of the present knowledge and practice on the prevention of this problem in the wine industry. Brettanomyces bruxellensis, or its teleomorph, Dekkera bruxellensis, are rarely found in the natural environment and, although frequently isolated from fermenting substrates, their numbers are relatively low when compared with other fermenting species. Despite this rarity, they have long been studied for their unusual metabolical features (e.g., the Custers effect. Rising interest over the last decades is mostly due to volatile phenol production affecting high quality red wines worldwide. The challenges have been dealt with together by researchers and winemakers in an effective way and this has enabled a state where, presently, knowledge and prevention of the problem at the winery level is readily accessible. Today, the main issues have shifted from technological to sensory science concerning the effects of metabolites other than ethylphenols and the over estimation of the detrimental impact by ethylphenols on flavor. Hopefully, these questions will continue to be tackled together by science and industry for the benefit of wine enjoyment.

  8. Construction of a genetically modified wine yeast strain expressing the Aspergillus aculeatus rhaA gene, encoding an -L-Rhamnosidase of enological interest

    NARCIS (Netherlands)

    Manzanares, P.; Orejas, M.; Vicente Gil, J.; Graaff, de L.H.; Visser, J.; Ramon, D.

    2003-01-01

    The Aspergillus aculeatus rhaA gene encoding an alpha-L-rhamnosidase has been expressed in both laboratory and industrial wine yeast strains. Wines produced in microvinifications, conducted using a combination of the genetically modified industrial strain expressing rhaA and another strain

  9. The application of non-Saccharomyces yeast in fermentations with limited aeration as a strategy for the production of wine with reduced alcohol content.

    Science.gov (United States)

    Contreras, A; Hidalgo, C; Schmidt, S; Henschke, P A; Curtin, C; Varela, C

    2015-07-16

    High alcohol concentrations reduce the complexity of wine sensory properties. In addition, health and economic drivers have the wine industry actively seeking technologies that facilitate the production of wines with lower alcohol content. One of the simplest approaches to achieve this aim would be the use of wine yeast strains which are less efficient at transforming grape sugars into ethanol, however commercially available wine yeasts produce very similar ethanol yields. Non-conventional yeast, in particular non-Saccharomyces species, have shown potential for producing wines with lower alcohol content. These yeasts are naturally present in the early stages of fermentation but in general are not capable of completing alcoholic fermentation. We have evaluated 48 non-Saccharomyces isolates to identify strains that, with limited aeration and in sequential inoculation regimes with S. cerevisiae, could be used for the production of wine with lower ethanol concentration. Two of these, Torulaspora delbrueckii AWRI1152 and Zygosaccharomyces bailii AWRI1578, enabled the production of wine with reduced ethanol concentration under limited aerobic conditions. Depending on the aeration regime T. delbrueckii AWRI1152 and Z. bailii AWRI1578 showed a reduction in ethanol concentration of 1.5% (v/v) and 2.0% (v/v) respectively, compared to the S. cerevisiae anaerobic control. Copyright © 2015 Elsevier B.V. All rights reserved.

  10. Glycerol production by Oenococcus oeni during sequential and simultaneous cultures with wine yeast strains.

    Science.gov (United States)

    Ale, Cesar E; Farías, Marta E; Strasser de Saad, Ana M; Pasteris, Sergio E

    2014-07-01

    Growth and fermentation patterns of Saccharomyces cerevisiae, Kloeckera apiculata, and Oenococcus oeni strains cultured in grape juice medium were studied. In pure, sequential and simultaneous cultures, the strains reached the stationary growth phase between 2 and 3 days. Pure and mixed K. apiculata and S. cerevisiae cultures used mainly glucose, producing ethanol, organic acids, and 4.0 and 0.1 mM glycerol, respectively. In sequential cultures, O. oeni achieved about 1 log unit at 3 days using mainly fructose and L-malic acid. Highest sugars consumption was detected in K. apiculata supernatants, lactic acid being the major end-product. 8.0 mM glycerol was found in 6-day culture supernatants. In simultaneous cultures, total sugars and L-malic acid were used at 3 days and 98% of ethanol and glycerol were detected. This study represents the first report of the population dynamics and metabolic behavior of yeasts and O. oeni in sequential and simultaneous cultures and contributes to the selection of indigenous strains to design starter cultures for winemaking, also considering the inclusion of K. apiculata. The sequential inoculation of yeasts and O. oeni would enhance glycerol production, which confers desirable organoleptic characteristics to wines, while organic acids levels would not affect their sensory profile. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Solving Microbial Spoilage Problems in Processed Foods

    Science.gov (United States)

    Clavero, Rocelle

    This chapter surveys common microbial food spoilage processes. The chapter is organized by food products and includes sections addressing spoilage in meat, poultry, fish; dairy products (milk, butter, cheese); beverage products; bakery products; canned foods; fruit and confectionery products; and emulsions. It addresses the isolation and identification of spoilage organisms and provides several case studies as examples. It introduces various organisms responsible for spoilage including Gram-positive lactic acid bacteria, Gram-negative aerobic bacteria, yeasts, molds, and fungal contaminants. Throughout the chapter, attention is given to when, where, and how spoilage organisms enter the food processing chain. Troubleshooting techniques are suggested. The effect (or lack of effect) of heating, dehydration, pH change, cooling, and sealing on various organisms is explained throughout. The chapter contains four tables that connect specific organisms to various spoilage manifestations in a variety of food products.

  12. Influence of nitrogen sources on growth and fermentation performance of different wine yeast species during alcoholic fermentation

    DEFF Research Database (Denmark)

    Kemsawasd, Varongsiri; Monteiro Lomba Viana, Tiago; Ardö, Ylva

    2015-01-01

    -Saccharomyces yeast species (Lachancea thermotolerans, Metschnikowia pulcherrima, Hanseniaspora uvarum and Torulaspora delbrueckii) was investigated during alcoholic fermentation. Briefly, the N-sources with beneficial effects on all performance parameters (or for the majority of them) for each yeast species were...... for L. thermotolerans, H. uvarum and M. pulcherrima, single amino acids affected growth and fermentation performance to the same extent as the mixtures. Moreover, we found groups of N-sources with similar effects on the growth and/or fermentation performance of two or more yeast species. Finally...... species under oxygen-limited conditions, which, in turn, may be used to, e.g. optimize growth and fermentation performance of the given yeast upon N-source supplementation during wine fermentations....

  13. In Vitro Antifungal Effect of Black Cumin Seed Quinones against Dairy Spoilage Yeasts at Different Acidity Levels

    Czech Academy of Sciences Publication Activity Database

    Halamová, K.; Kokoška, L.; Flešar, J.; Skleničková, O.; Svobodová, B.; Maršík, Petr

    2010-01-01

    Roč. 73, č. 12 (2010), s. 2291-2295 ISSN 0362-028X R&D Projects: GA ČR GA525/08/1179; GA ČR GD525/08/H060 Institutional research plan: CEZ:AV0Z50380511 Keywords : yeast strains * culture conditions * antimicrobial assay Subject RIV: GM - Food Processing Impact factor: 1.720, year: 2010 www.ingentaconnect.com/content/iafp/jfp/2010/00000073/00000012/art00021

  14. Yeast population dynamics reveal a potential 'collaboration' between Metschnikowia pulcherrima and Saccharomyces uvarum for the production of reduced alcohol wines during Shiraz fermentation.

    Science.gov (United States)

    Contreras, A; Curtin, C; Varela, C

    2015-02-01

    The wine sector is actively seeking strategies and technologies that facilitate the production of wines with lower alcohol content. One of the simplest approaches to achieve this aim would be the use of wine yeast strains which are less efficient at transforming grape sugars into ethanol; however, commercial wine yeasts have very similar ethanol yields. We recently demonstrated that Metschnikowia pulcherrima AWRI1149 was able to produce wine with reduced alcohol concentration when used in sequential inoculation with a wine strain of Saccharomyces cerevisiae. Here, different inoculation regimes were explored to study the effect of yeast population dynamics and potential yeast interactions on the metabolism of M. pulcherrima AWRI1149 during fermentation of non-sterile Shiraz must. Of all inoculation regimes tested, only ferments inoculated with M. pulcherrima AWRI1149 showed reduced ethanol concentration. Population dynamics revealed the presence of several indigenous yeast species and one of these, Saccharomyces uvarum (AWRI 2846), was able to produce wine with reduced ethanol concentration in sterile conditions. Both strains however, were inhibited when a combination of three non-Saccharomyces strains, Hanseniaspora uvarum AWRI863, Pichia kluyveri AWRI1896 and Torulaspora delbrueckii AWRI2845 were inoculated into must, indicating that the microbial community composition might impact on the growth of M. pulcherrima AWRI1149 and S. uvarum AWRI 2846. Our results indicate that mixed cultures of M. pulcherrima AWRI1149 and S. uvarum AWRI2846 enable an additional reduction of wine ethanol concentration compared to the same must fermented with either strain alone. This work thus provides a foundation to develop inoculation regimes for the successful application of non-cerevisiae yeast to the production of wines with reduced alcohol.

  15. Adaptive response to chronic mild ethanol stress involves ROS, sirtuins and changes in chromosome dosage in wine yeasts.

    Science.gov (United States)

    Adamczyk, Jagoda; Deregowska, Anna; Skoneczny, Marek; Skoneczna, Adrianna; Kwiatkowska, Aleksandra; Potocki, Leszek; Rawska, Ewa; Pabian, Sylwia; Kaplan, Jakub; Lewinska, Anna; Wnuk, Maciej

    2016-05-24

    Industrial yeast strains of economic importance used in winemaking and beer production are genomically diverse and subjected to harsh environmental conditions during fermentation. In the present study, we investigated wine yeast adaptation to chronic mild alcohol stress when cells were cultured for 100 generations in the presence of non-cytotoxic ethanol concentration. Ethanol-induced reactive oxygen species (ROS) and superoxide signals promoted growth rate during passages that was accompanied by increased expression of sirtuin proteins, Sir1, Sir2 and Sir3, and DNA-binding transcription regulator Rap1. Genome-wide array-CGH analysis revealed that yeast genome was shaped during passages. The gains of chromosomes I, III and VI and significant changes in the gene copy number in nine functional gene categories involved in metabolic processes and stress responses were observed. Ethanol-mediated gains of YRF1 and CUP1 genes were the most accented. Ethanol also induced nucleolus fragmentation that confirms that nucleolus is a stress sensor in yeasts. Taken together, we postulate that wine yeasts of different origin may adapt to mild alcohol stress by shifts in intracellular redox state promoting growth capacity, upregulation of key regulators of longevity, namely sirtuins and changes in the dosage of genes involved in the telomere maintenance and ion detoxification.

  16. Effect of yeast strain and some nutritional factors on tannin composition and potential astringency of model wines.

    Science.gov (United States)

    Rinaldi, Alessandra; Blaiotta, Giuseppe; Aponte, Maria; Moio, Luigi

    2016-02-01

    Nine Saccharomyces cerevisiae cultures, isolated from different sources, were tested for their ability to reduce tannins reactive towards salivary proteins, and potentially responsible for wine astringency. Strains were preliminary genetically characterized and evaluated for physiological features of technological interest. Laboratory-scale fermentations were performed in three synthetic media: CT) containing enological grape tannin; CTP) CT supplemented with organic nitrogen sources; CTPV) CTP supplemented with vitamins. Adsorption of total tannins, tannins reactive towards salivary proteins, yellow pigments, phenolics having antioxidant activity, and total phenols, characterizing the enological tannin, was determined by spectrophotometric methods after fermentation. The presence of vitamins and peptones in musts greatly influenced the adsorption of tannins reactive towards salivary proteins (4.24 g/L gallic acid equivalent), thus promoting the reduction of the potential astringency of model wines. With reference to the different phenolic classes, yeast strains showed different adsorption abilities. From a technological point of view, the yeast choice proved to be crucial in determining changes in gustative and mouthfeel profile of red wines and may assist winemakers to modulate colour and astringency of wine. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Identification of yeasts Isolated from processed and frozen cocoa (Theobroma cacao pulp for wine production

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Trindade

    1999-01-01

    Full Text Available The alternative use of cocoa (Theobroma cacao for wine production was tested. The pulp samples, obtained from Formosa farm, Itacaré, Brazil, were diluted, homogenized and inoculated on Sabouraud dextrose agar medium (SDA and incubated at 28º C for 5-8 days. Selected colonies were tested for the ability to ferment cocoa pulp and divided into fermentative, non-fermentative and weak/late fermentative species. Isolates characterized as fermentative were further tested in a small-scale wine production plant and identified. Species from the genus Brettanomyces constituted the main fermentative yeasts, with the exception of two Kloeckera apis samples. The final wine product was normally pale or clear, making clarification unnecessary, and with a sweet or dry pleasant flavor. The predominance of Brettanomyces species in cocoa pulp indicated its ecological importance in this environment and pointed to an active role of Brettanomyces in the deterioration process of the processed cocoa pulp.O uso alternativo de cacau (Theobroma cacao para produção de vinho foi testado. A polpa de cacau foi obtida da Fazenda Formosa, Itacaré, Brasil. As amostras de polpa foram diluídas, homogeneizadas e inoculadas em meio de Sabouraud dextrose e incubadas a 28°C por 5-8 dias. Colônias selecionadas foram testadas quanto à habilidade de fermentar a polpa de cacau e divididas em fermentadoras, não-fermentadoras e fermentadoras lentas. As amostras fermentadoras foram identificadas e testadas para produção de vinho de cacau em escala piloto. A maioria das amostras fermentadoras pertencem ao gênero Brettanomyces, com exceção de duas amostras de Kloeckera apis. O vinho obtido apresentou coloração fraca e clara, tornando a clarificação desnecessária, além de sabor doce e agradável. A predominância de espécies de Brettanomyces na polpa de cacau poderia indicar sua importância ecológica neste ambiente e sugere uma participação ativa dessas leveduras nos

  18. Enological Tannin Effect on Red Wine Color and Pigment Composition and Relevance of the Yeast Fermentation Products

    Directory of Open Access Journals (Sweden)

    Ignacio García-Estévez

    2017-11-01

    Full Text Available Enological tannins are widely used in the winemaking process either to improve different wine characteristics (color stability, among others or to compensate for low tannin levels. In this work, the influence of the addition of two different enological tannins, mainly composed of hydrolysable (ellagitannins and condensed tannins, on the evolution of color and pigment composition of two different types of model systems containing the five main grape anthocyanins was studied. In addition, the effect of the addition of an enological tannin on the color and pigment composition of red wines made from Vitis vinifera L. cv Tempranillo grapes was also studied by high-performance liquid chromatography with diode array detection coupled to mass spectrometry (HPLC-DAD-MS. Results showed that, in model systems, the addition of the enological tannin favored the formation of anthocyanin-derived pigments, such as A-type and B-type vitisins and flavanol-anthocyanin condensation products, provided that the yeast precursors were previously supplied. Moreover, model systems containing the enological tannins were darker and showed higher values of chroma at the end of the study than control ones. The higher formation of these anthocyanin-derived pigments was also observed in the red wines containing the enological tannin. Moreover, these wine also showed lower lightness (L* values and higher chroma (C*ab values than control wines, indicating a higher stabilization of color.

  19. Enological Tannin Effect on Red Wine Color and Pigment Composition and Relevance of the Yeast Fermentation Products.

    Science.gov (United States)

    García-Estévez, Ignacio; Alcalde-Eon, Cristina; Puente, Víctor; Escribano-Bailón, M Teresa

    2017-11-23

    Enological tannins are widely used in the winemaking process either to improve different wine characteristics (color stability, among others) or to compensate for low tannin levels. In this work, the influence of the addition of two different enological tannins, mainly composed of hydrolysable (ellagitannins) and condensed tannins, on the evolution of color and pigment composition of two different types of model systems containing the five main grape anthocyanins was studied. In addition, the effect of the addition of an enological tannin on the color and pigment composition of red wines made from Vitis vinifera L. cv Tempranillo grapes was also studied by high-performance liquid chromatography with diode array detection coupled to mass spectrometry (HPLC-DAD-MS). Results showed that, in model systems, the addition of the enological tannin favored the formation of anthocyanin-derived pigments, such as A-type and B-type vitisins and flavanol-anthocyanin condensation products, provided that the yeast precursors were previously supplied. Moreover, model systems containing the enological tannins were darker and showed higher values of chroma at the end of the study than control ones. The higher formation of these anthocyanin-derived pigments was also observed in the red wines containing the enological tannin. Moreover, these wine also showed lower lightness (L*) values and higher chroma (C* ab ) values than control wines, indicating a higher stabilization of color.

  20. Evaluation of the ability of commercial wine yeasts to form biofilms (mats) and adhere to plastic: implications for the microbiota of the winery environment.

    Science.gov (United States)

    Tek, Ee Lin; Sundstrom, Joanna F; Gardner, Jennifer M; Oliver, Stephen G; Jiranek, Vladimir

    2018-02-01

    Commercially available active dried wine yeasts are regularly used by winemakers worldwide to achieve reliable fermentations and obtain quality wine. This practice has led to increased evidence of traces of commercial wine yeast in the vineyard, winery and uninoculated musts. The mechanism(s) that enables commercial wine yeast to persist in the winery environment and the influence to native microbial communities on this persistence is poorly understood. This study has investigated the ability of commercial wine yeasts to form biofilms and adhere to plastic. The results indicate that the biofilms formed by commercial yeasts consist of cells with a combination of different lifestyles (replicative and non-replicative) and growth modes including invasive growth, bud elongation, sporulation and a mat sectoring-like phenotype. Invasive growth was greatly enhanced on grape pulp regardless of strain, while adhesion on plastic varied between strains. The findings suggest a possible mechanism that allows commercial yeast to colonise and survive in the winery environment, which may have implications for the indigenous microbiota profile as well as the population profile in uninoculated fermentations if their dissemination is not controlled. © FEMS 2018. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. Metagenomic sequencing reveals the relationship between microbiota composition and quality of Chinese Rice Wine.

    Science.gov (United States)

    Hong, Xutao; Chen, Jing; Liu, Lin; Wu, Huan; Tan, Haiqin; Xie, Guangfa; Xu, Qian; Zou, Huijun; Yu, Wenjing; Wang, Lan; Qin, Nan

    2016-05-31

    Chinese Rice Wine (CRW) is a common alcoholic beverage in China. To investigate the influence of microbial composition on the quality of CRW, high throughput sequencing was performed for 110 wine samples on bacterial 16S rRNA gene and fungal Internal Transcribed Spacer II (ITS2). Bioinformatic analyses demonstrated that the quality of yeast starter and final wine correlated with microbial taxonomic composition, which was exemplified by our finding that wine spoilage resulted from a high proportion of genus Lactobacillus. Subsequently, based on Lactobacillus abundance of an early stage, a model was constructed to predict final wine quality. In addition, three batches of 20 representative wine samples selected from a pool of 110 samples were further analyzed in metagenomics. The results revealed that wine spoilage was due to rapid growth of Lactobacillus brevis at the early stage of fermentation. Gene functional analysis indicated the importance of some pathways such as synthesis of biotin, malolactic fermentation and production of short-chain fatty acid. These results led to a conclusion that metabolisms of microbes influence the wine quality. Thus, nurturing of beneficial microbes and inhibition of undesired ones are both important for the mechanized brewery.

  2. PENGARUH BERBAGAI MERK DRIED YEAST (Saccharomyces sp. DAN pH AWAL FERMENTASI TERHADAP KARAKTERISTIK WINE SALAK

    Directory of Open Access Journals (Sweden)

    Ida Bagus Wayan Gunam

    2017-09-01

    Full Text Available The purpose of this research were to find out the effect of different of dried yeast and initial pH of fermentation on the characteristic of salacca wine, and to determine the appropriate of kind of dried yeast and initial pH of fermentation to produce salacca wine with the best characteristic. This research used Randomized Block Design with factorial pattern. The first factor was the kind of dried yeast brand that consisted of 3 kinds namely Lalvin, Levure and Alcotec. The second factor consisted of 5 levels of initial pH, namely 3.5; 4; 4.5; 5; and 5.5. Each treatment was done 2 times, in order to obtain 30 trial units. The data obtained was analyzed using ANOVA followed by Duncans test. Interactions between treatments had very significant effect on the ethanol content, reduction sugar content, and pH, but had significant effect on acid total content. The best treatment was to use the Alcotec brand dried yeast with a treatment of initial pH as 4, with the following characteristics: ethanol content 12.40%, negative content of methanol, reduction sugar content 5.87%, acid total content 0.20%, pH 3.5 after the fermentation, the color was enough pure yellow, the flavor was strong enough, the taste was strong enough, and rather liked over all acceptance.

  3. Isolation and identification of mold and yeast in medombae, a rice wine starter culture from Kompong Cham Province, Cambodia

    Directory of Open Access Journals (Sweden)

    Chay, C.,

    2017-07-01

    Full Text Available Medombae is a dried starter culture used for traditional rice wine processing in Cambodia. However, studies on the role of mold and yeast present and their efficacy for rice wine fermentation are still limited. Cultural and morphological tests revealed that the isolated representative mold strains were isolated based on the method of identification used as Mucor spp and Rhizopus oryzae. On the other hand, the biochemical properties of the first yeast isolate using the Vitek 2 identification system and YST Card identification suggests its identity as Candida tropicalis. The second yeast strain examined for its morphological and cultural characteristic using agar slide technique, and its protein profile which was compared to the reference and sample protein masses using Biomerieux Vitek MS (MALD-TOF showed the presence of Saccharomyces cerevisiae. The biochemical characteristics and cellular characteristics of the third yeast isolate as described by Lodder (1970 and Kreger-Van Rij (1984 confirmed its identity as Saccharomycopsis spp. The DNA test of identification of the isolates should be conducted to further confirm the identity of the isolates.

  4. A set of nutrient limitations trigger yeast cell death in a nitrogen-dependent manner during wine alcoholic fermentation.

    Directory of Open Access Journals (Sweden)

    Camille Duc

    Full Text Available Yeast cell death can occur during wine alcoholic fermentation. It is generally considered to result from ethanol stress that impacts membrane integrity. This cell death mainly occurs when grape musts processing reduces lipid availability, resulting in weaker membrane resistance to ethanol. However the mechanisms underlying cell death in these conditions remain unclear. We examined cell death occurrence considering yeast cells ability to elicit an appropriate response to a given nutrient limitation and thus survive starvation. We show here that a set of micronutrients (oleic acid, ergosterol, pantothenic acid and nicotinic acid in low, growth-restricting concentrations trigger cell death in alcoholic fermentation when nitrogen level is high. We provide evidence that nitrogen signaling is involved in cell death and that either SCH9 deletion or Tor inhibition prevent cell death in several types of micronutrient limitation. Under such limitations, yeast cells fail to acquire any stress resistance and are unable to store glycogen. Unexpectedly, transcriptome analyses did not reveal any major changes in stress genes expression, suggesting that post-transcriptional events critical for stress response were not triggered by micronutrient starvation. Our data point to the fact that yeast cell death results from yeast inability to trigger an appropriate stress response under some conditions of nutrient limitations most likely not encountered by yeast in the wild. Our conclusions provide a novel frame for considering both cell death and the management of nutrients during alcoholic fermentation.

  5. The genome of wine yeast Dekkera bruxellensis provides a tool to explore its food-related properties

    Energy Technology Data Exchange (ETDEWEB)

    Piskur, Jure; Ling, Zhihao; Marcet-Houben, Marina; Ishchuk, Olena P.; Aerts, Andrea; LaButti, Kurt; Copeland, Alex; Lindquist, Erika; Barry, Kerrie; Compagno, Concetta; Bisson, Linda; Grigoriev, Igor V.; Gabaldon, Toni; Phister, Trevor

    2012-03-14

    The yeast Dekkera/Brettanomyces bruxellensis can cause enormous economic losses in wine industry due to production of phenolic off-flavor compounds. D. bruxellensis is a distant relative of baker's yeast Saccharomyces cerevisiae. Nevertheless, these two yeasts are often found in the same habitats and share several food-related traits, such as production of high ethanol levels and ability to grow without oxygen. In some food products, like lambic beer, D. bruxellensis can importantly contribute to flavor development. We determined the 13.4 Mb genome sequence of the D. bruxellensis strain Y879 (CBS2499) and deduced the genetic background of several ?food-relevant? properties and evolutionary history of this yeast. Surprisingly, we find that this yeast is phylogenetically distant to other food-related yeasts and most related to Pichia (Komagataella) pastoris, which is an aerobic poor ethanol producer. We further show that the D. bruxellensis genome does not contain an excess of lineage specific duplicated genes nor a horizontally transferred URA1 gene, two crucial events that promoted the evolution of the food relevant traits in the S. cerevisiae lineage. However, D. bruxellensis has several independently duplicated ADH and ADH-like genes, which are likely responsible for metabolism of alcohols, including ethanol, and also a range of aromatic compounds.

  6. Effect of selected Saccharomyces cerevisiae yeast strains and different aging techniques on the polysaccharide and polyphenolic composition and sensorial characteristics of Cabernet Sauvignon red wines.

    Science.gov (United States)

    del Barrio-Galán, Rubén; Cáceres-Mella, Alejandro; Medel-Marabolí, Marcela; Peña-Neira, Álvaro

    2015-08-15

    The objective of this work was to study the effect of two Saccharomyces cerevisiae yeast strains with different capabilities of polysaccharide liberation during alcoholic fermentation in addition to subsequent aging on lees with or without oak wood chips as well as aging with commercial inactive dry yeast on the physical, chemical and sensorial characteristics of Cabernet Sauvignon red wines. The HPS (high levels of polysaccharides) yeast strain released higher amounts of polysaccharides (429 g L(-1)) than EC1118 (390 g L(-1)) during alcoholic fermentation, but the concentration equalized during the aging period (424 and 417 g L(-1) respectively). All aging techniques increased the polysaccharide concentration, but the increase was dependent on the technique applied. A higher liberation of polysaccharides reduced the concentration of most of the phenolic families analyzed. Moreover, no clear effect of the different aging techniques used in this study on color stabilization was found. The HPS wines were better valued than the EC1118 wines by the panel of tasters after alcoholic fermentation. In general, the HPS wines showed better physicochemical and sensorial characteristics than the EC1118 wines. According to the results obtained during the aging period, all aging techniques contributed to improve wine quality, but it was difficult to establish the technique that allowed the best wine to be obtained, because it depended on the aging technique used and the period of aging. © 2014 Society of Chemical Industry.

  7. Microbiological spoilage of fish and fish products

    DEFF Research Database (Denmark)

    Gram, Lone; Huss, Hans Henrik

    1996-01-01

    Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative...... biochemical indicators of spoilage. Shewanzella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram......- positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish...

  8. Use of a wine yeast deletion collection reveals genes that influence fermentation performance under low-nitrogen conditions.

    Science.gov (United States)

    Peter, Josephine J; Watson, Tommaso L; Walker, Michelle E; Gardner, Jennifer M; Lang, Tom A; Borneman, Anthony; Forgan, Angus; Tran, Tina; Jiranek, Vladimir

    2018-05-01

    A deficiency of nitrogenous nutrients in grape juice can cause stuck and sluggish alcoholic fermentation, which has long been a problem in winemaking. Nitrogen requirements vary between wine yeast strains, and the ability of yeast to assimilate nitrogen depends on the nature and concentration of nitrogen present in the medium. In this study, a wine yeast gene deletion collection (1844 deletants in the haploid AWRI1631 background) was screened to identify genes whose deletion resulted in a reduction in the time taken to utilise all sugars when grown in a chemically defined grape juice medium supplemented with limited nitrogen (75 mg L-1 as a free amino acid mixture). Through micro-scale and laboratory-scale fermentations, 15 deletants were identified that completed fermentation in a shorter time than the wildtype (c.a. 15%-59% time reduction). This group of genes was annotated to biological processes including protein modification, transport, metabolism and ubiquitination (UBC13, MMS2, UBP7, UBI4, BRO1, TPK2, EAR1, MRP17, MFA2 and MVB12), signalling (MFA2) and amino acid metabolism (AAT2). Deletion of MFA2, encoding mating factor-a, resulted in a 55% decrease in fermentation duration. Mfa2Δ was chosen for further investigation to understand how this gene deletion conferred fermentation efficiency in limited nitrogen conditions.

  9. High pressure inactivation of Brettanomyces bruxellensis in red wine.

    Science.gov (United States)

    van Wyk, Sanelle; Silva, Filipa V M

    2017-05-01

    Brettanomyces bruxellensis ("Brett") is a major spoilage concern for the wine industry worldwide, leading to undesirable sensory properties. Sulphur dioxide, is currently the preferred method for wine preservation. However, due to its negative effects on consumers, the use of new alternative non-thermal technologies are increasingly being investigated. The aim of this study was to determine and model the effect of high pressure processing (HPP) conditions and yeast strain on the inactivation of "Brett" in Cabernet Sauvignon wine. Processing at 200 MPa for 3 min resulted in 5.8 log reductions. However higher pressure is recommended to achieve high throughput in the wine industry, for example >6.0 log reductions were achieved after 400 MPa for 5 s. The inactivation of B. bruxellensis is pressure and time dependent, with increased treatment time and pressure leading to increased yeast inactivation. It was also found that yeast strain had a significant effect on HPP inactivation, with AWRI 1499 being the most resistant strain. The Weibull model successfully described the HPP "Brett" inactivation. HPP is a viable alternative for the inactivation of B. bruxellensis in wine, with the potential to reduce the industry's reliance on sulphur dioxide. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Oxygen Response of the Wine Yeast Saccharomyces cerevisiae EC1118 Grown under Carbon-Sufficient, Nitrogen-Limited Enological Conditions

    Science.gov (United States)

    Aceituno, Felipe F.; Orellana, Marcelo; Torres, Jorge; Mendoza, Sebastián; Slater, Alex W.; Melo, Francisco

    2012-01-01

    Discrete additions of oxygen play a critical role in alcoholic fermentation. However, few studies have quantitated the fate of dissolved oxygen and its impact on wine yeast cell physiology under enological conditions. We simulated the range of dissolved oxygen concentrations that occur after a pump-over during the winemaking process by sparging nitrogen-limited continuous cultures with oxygen-nitrogen gaseous mixtures. When the dissolved oxygen concentration increased from 1.2 to 2.7 μM, yeast cells changed from a fully fermentative to a mixed respirofermentative metabolism. This transition is characterized by a switch in the operation of the tricarboxylic acid cycle (TCA) and an activation of NADH shuttling from the cytosol to mitochondria. Nevertheless, fermentative ethanol production remained the major cytosolic NADH sink under all oxygen conditions, suggesting that the limitation of mitochondrial NADH reoxidation is the major cause of the Crabtree effect. This is reinforced by the induction of several key respiratory genes by oxygen, despite the high sugar concentration, indicating that oxygen overrides glucose repression. Genes associated with other processes, such as proline uptake, cell wall remodeling, and oxidative stress, were also significantly affected by oxygen. The results of this study indicate that respiration is responsible for a substantial part of the oxygen response in yeast cells during alcoholic fermentation. This information will facilitate the development of temporal oxygen addition strategies to optimize yeast performance in industrial fermentations. PMID:23001663

  11. Oxygen response of the wine yeast Saccharomyces cerevisiae EC1118 grown under carbon-sufficient, nitrogen-limited enological conditions.

    Science.gov (United States)

    Aceituno, Felipe F; Orellana, Marcelo; Torres, Jorge; Mendoza, Sebastián; Slater, Alex W; Melo, Francisco; Agosin, Eduardo

    2012-12-01

    Discrete additions of oxygen play a critical role in alcoholic fermentation. However, few studies have quantitated the fate of dissolved oxygen and its impact on wine yeast cell physiology under enological conditions. We simulated the range of dissolved oxygen concentrations that occur after a pump-over during the winemaking process by sparging nitrogen-limited continuous cultures with oxygen-nitrogen gaseous mixtures. When the dissolved oxygen concentration increased from 1.2 to 2.7 μM, yeast cells changed from a fully fermentative to a mixed respirofermentative metabolism. This transition is characterized by a switch in the operation of the tricarboxylic acid cycle (TCA) and an activation of NADH shuttling from the cytosol to mitochondria. Nevertheless, fermentative ethanol production remained the major cytosolic NADH sink under all oxygen conditions, suggesting that the limitation of mitochondrial NADH reoxidation is the major cause of the Crabtree effect. This is reinforced by the induction of several key respiratory genes by oxygen, despite the high sugar concentration, indicating that oxygen overrides glucose repression. Genes associated with other processes, such as proline uptake, cell wall remodeling, and oxidative stress, were also significantly affected by oxygen. The results of this study indicate that respiration is responsible for a substantial part of the oxygen response in yeast cells during alcoholic fermentation. This information will facilitate the development of temporal oxygen addition strategies to optimize yeast performance in industrial fermentations.

  12. PTR-MS Characterization of VOCs Associated with Commercial Aromatic Bakery Yeasts of Wine and Beer Origin

    Directory of Open Access Journals (Sweden)

    Vittorio Capozzi

    2016-04-01

    Full Text Available In light of the increasing attention towards “green” solutions to improve food quality, the use of aromatic-enhancing microorganisms offers the advantage to be a natural and sustainable solution that did not negatively influence the list of ingredients. In this study, we characterize, for the first time, volatile organic compounds (VOCs associated with aromatic bakery yeasts. Three commercial bakery starter cultures, respectively formulated with three Saccharomyces cerevisiae strains, isolated from white wine, red wine, and beer, were monitored by a proton-transfer-reaction time-of-flight mass spectrometer (PTR-ToF-MS, a direct injection analytical technique for detecting volatile organic compounds with high sensitivity (VOCs. Two ethanol-related peaks (m/z 65.059 and 75.080 described qualitative differences in fermentative performances. The release of compounds associated to the peaks at m/z 89.059, m/z 103.075, and m/z 117.093, tentatively identified as acetoin and esters, are coherent with claimed flavor properties of the investigated strains. We propose these mass peaks and their related fragments as biomarkers to optimize the aromatic performances of commercial preparations and for the rapid massive screening of yeast collections.

  13. Influence of yeast strain, canopy management, and site on the volatile composition and sensory attributes of cabernet sauvignon wines from Western Australia.

    Science.gov (United States)

    Robinson, Anthony L; Boss, Paul K; Heymann, Hildegarde; Solomon, Peter S; Trengove, Robert D

    2011-04-13

    Understanding what factors are the major influences on wine composition will assist in the successful management of grape composition in the vineyard and/or variables in the winery to produce wines with specific sensory attributes. A recently developed analytical method [headspace solid-phase microextraction comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry] was employed to analyze over 350 volatile compounds in research scale wines and was combined with descriptive sensory analysis. Both compositional and sensory results showed significant differences among the wines, and in many cases, multiple factors influenced the abundance of wine volatile compounds. Site had the most significant influence on sensory scores and wine composition, followed by canopy management. Unexpectedly, yeast strain had no significant sensory effect despite the fact that a number of volatile compounds were significantly different in the wines made from different strains. PLS analysis, combining the sensory and chemical analyses, also supports the concept of volatile compound interactions contributing to the aroma characteristics of Cabernet Sauvignon wine.

  14. Impact of Australian Dekkera bruxellensis strains grown under oxygen-limited conditions on model wine composition and aroma.

    Science.gov (United States)

    Curtin, Chris D; Langhans, Geoffrey; Henschke, Paul A; Grbin, Paul R

    2013-12-01

    Spoilage of red wine by the yeast species Dekkera bruxellensis is a common problem for the global wine industry. When conditions are conducive for growth of these yeasts in wine, they efficiently convert non-volatile hydroxycinnamic acids into aroma-active ethylphenols, thereby reducing the quality of the wine. It has been demonstrated previously that dissolved oxygen is a key factor which stimulates D. bruxellensis growth in wine. We demonstrate that whereas the presence of oxygen accelerates the growth of this species, oxygen-limited conditions favour 4-ethylphenol production. Consequently, we evaluated wine spoilage potential of three D. bruxellensis strains (AWRI1499, AWRI1608 and AWRI1613) under oxygen-limited conditions. Each strain was cultured in a chemically-defined wine medium and the fermentation products were analysed using HPLC and HS-SPME-GC/MS. The strains displayed different growth characteristics but were equally capable of producing ethylphenols. On the other hand, significant differences were observed for 18 of the remaining 33 metabolites analysed and duo-trio sensory analysis indicated significant aroma differences between wines inoculated with AWRI1499 and AWRI1613. When these wines were spiked with low concentrations of 4-ethylphenol and 4-ethylguaiacol, no sensorial differences could be perceived. Together these data suggest that the three predominant D. bruxellensis strains previously isolated during a large survey of Australian wineries do not differ substantively in their capacity to grow in, and spoil, a model wine medium. Copyright © 2013 Elsevier Ltd. All rights reserved.

  15. Volatile sulphur compounds in wines related to yeast metabolism and nitrogen composition of grape musts

    OpenAIRE

    Moreira, N.; Mendesa, F.; Pereira, O.; Pinho, P. Guedes de

    2002-01-01

    The influence of nitrogen compounds in grape musts on the content of sulphur compounds of wines was studied. Different vinifications were performed with the addition of methionine (20 mg l−1) and/or cysteine (40 mg l−1) to grape musts before alcoholic fermentation. Six grape musts, with different nitrogen composition, from cultivars of the ‘Vinhos Verdes’ Region, in Portugal, were used. Addition of methionine to grape musts enhanced the content of wines in 3-(methylthio)-1-propanol, ...

  16. Microbiological spoilage of fish and fish products.

    Science.gov (United States)

    Gram, L; Huss, H H

    1996-11-01

    Spoilage of fresh and lightly preserved fish products is caused by microbial action. This paper reviews the current knowledge in terms of the microbiology of fish and fish products with particular emphasis on identification of specific spoilage bacteria and the qualitative and quantitative biochemical indicators of spoilage. Shewanella putrefaciens and Pseudomonas spp. are the specific spoilage bacteria of iced fresh fish regardless of the origin of the fish. Modified atmosphere stored marine fish from temperate waters are spoiled by the CO2 resistant Photobacterium phosphoreum whereas Gram-positive bacteria are likely spoilers of CO2 packed fish from fresh or tropical waters. Fish products with high salt contents may spoil due to growth of halophilic bacteria (salted fish) or growth of anaerobic bacteria and yeasts (barrel salted fish). Whilst the spoilage of fresh and highly salted fish is well understood, much less is known about spoilage of lightly preserved fish products. It is concluded that the spoilage is probably caused by lactic acid bacteria, certain psychotrophic Enterobacteriaceae and/or Photobacterium phosphoreum. However, more work is needed in this area.

  17. Effect of kaolin silver complex on the control of populations of Brettanomyces and acetic acid bacteria in wine.

    Science.gov (United States)

    Izquierdo-Cañas, P M; López-Martín, R; García-Romero, E; González-Arenzana, L; Mínguez-Sanz, S; Chatonnet, P; Palacios-García, A; Puig-Pujol, A

    2018-05-01

    In this work, the effects of kaolin silver complex (KAgC) have been evaluated to replace the use of SO 2 for the control of spoilage microorganisms in the winemaking process. The results showed that KAgC at a dose of 1 g/L provided effective control against the development of B. bruxellensis and acetic acid bacteria. In wines artificially contaminated with an initial population of B. bruxellensis at 10 4 CFU/mL, a concentration proven to produce off flavors in wine, only residual populations of the contaminating yeast remained after 24 days of contact with the additive. Populations of acetic bacteria inoculated into wine at concentrations of 10 2 and 10 4  CFU/mL were reduced to negligible levels after 72 h of treatment with KAgC. The antimicrobial effect of KAgC against B. bruxellensis and acetic bacteria was also demonstrated in a wine naturally contaminated by these microorganisms, decreasing their population in a similar way to a chitosan treatment. Related to this effect, wines with KAgC showed lower concentrations of acetic acid and 4-ethyl phenol than wines without KAgC. The silver concentration from KAgC that remained in the finished wines was below the legal limits. These results demonstrated the effectiveness of KAgC to reduce spoilage microorganisms in winemaking.

  18. Microbiological Spoilage of Dairy Products

    Science.gov (United States)

    Ledenbach, Loralyn H.; Marshall, Robert T.

    The wide array of available dairy foods challenges the microbiologist, engineer, and technologist to find the best ways to prevent the entry of microorganisms, destroy those that do get in along with their enzymes, and prevent the growth and activities of those that escape processing treatments. Troublesome spoilage microorganisms include aerobic psychrotrophic Gram-negative bacteria, yeasts, molds, heterofermentative lactobacilli, and spore-forming bacteria. Psychrotrophic bacteria can produce large amounts of extracellular hydrolytic enzymes, and the extent of recontamination of pasteurized fluid milk products with these bacteria is a major determinant of their shelf life. Fungal spoilage of dairy foods is manifested by the presence of a wide variety of metabolic by-products, causing off-odors and flavors, in addition to visible changes in color or texture.

  19. Food spoilage - interactions between food spoilage bacteria

    DEFF Research Database (Denmark)

    Gram, Lone; Flodgaard, Lars; Rasch, Maria

    2002-01-01

    Food spoilage is a complex process and excessive amounts of foods are lost due to microbial spoilage even with modem day preservation techniques. Despite the heterogeneity in raw materials and processing conditions, the microflora that develops during storage and in spoiling foods can be predicted...... based on knowledge of the origin of the food, the substrate base and a few central preservation parameters such as temperature, atmosphere, a(w) and pH. Based on such knowledge, more detailed sensory, chemical and microbiological analysis can be carried out on the individual products to determine...... the actual specific spoilage organism. Whilst the chemical and physical parameters are the main determining factors for selection of spoilage microorganisms, a level of refinement may be found in some products in which the interactive behavior of microorganisms may contribute to their growth and/or spoilage...

  20. Application of multi-pass high pressure homogenization under variable temperature regimes to induce autolysis of wine yeasts.

    Science.gov (United States)

    Comuzzo, Piergiorgio; Calligaris, Sonia; Iacumin, Lucilla; Ginaldi, Federica; Voce, Sabrina; Zironi, Roberto

    2017-06-01

    The effects of the number of passes and processing temperature management (controlled vs. uncontrolled) were investigated during high pressure homogenization-induced autolysis of Saccharomyces bayanus wine yeasts, treated at 150MPa. Both variables were able to affect cell viability, and the release of soluble molecules (free amino acids, proteins and glucidic colloids), but the effect of temperature was more important. S. bayanus cells were completely inactivated in 10 passes without temperature control (corresponding to a processing temperature of 75°C). The two processing variables also affected the volatile composition of the autolysates produced: higher temperatures led to a lower concentration of volatile compounds. The management of the operating conditions may allow the compositional characteristics of the products to be modulated, making them suitable for different winemaking applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Rational selection of non-Saccharomyces wine yeasts for mixed starters based on ester formation and enological traits.

    Science.gov (United States)

    Viana, Fernando; Gil, José V; Genovés, Salvador; Vallés, Salvador; Manzanares, Paloma

    2008-09-01

    Thirty-eight yeast strains belonging to the genera Candida, Hanseniaspora, Pichia, Torulaspora and Zygosaccharomyces were screened for ester formation on synthetic microbiological medium. The genera Hanseniaspora and Pichia stood out as the best acetate ester producers. Based on the ester profile Hanseniaspora guilliermondii 11027 and 11102, Hanseniaspora osmophila 1471 and Pichia membranifaciens 10113 and 10550 were selected for further characterization of enological traits. When growing on must H. osmophila 1471, which displayed a glucophilic nature and was able to consume more than 90% of initial must sugars, produced levels of acetic acid, medium chain fatty acids and ethyl acetate, within the ranges described for wine. On the other hand, it was found to be a strong producer of 2-phenylethyl acetate. Our data suggest that H. osmophila 1471 is a good candidate for mixed starters, although the possible interactions with S. cerevisiae deserve further research.

  2. Pineapple (Ananas comosus L. Merr.) wine production in Angola: Characterisation of volatile aroma compounds and yeast native flora.

    Science.gov (United States)

    Dellacassa, Eduardo; Trenchs, Oriol; Fariña, Laura; Debernardis, Florencia; Perez, Gabriel; Boido, Eduardo; Carrau, Francisco

    2017-01-16

    A pineapple vinification process was conducted through inoculated and spontaneous fermentation to develop a process suitable for a quality beverage during two successive vintages in Huambo, Angola. Wines obtained with the conventional Saccharomyces cerevisiae strain, were analysed by gas chromatography, and a total of 61 volatile constituents were detected in the volatile fraction and 18 as glycosidically bound aroma compounds. Concentration levels of carbonyl and sulphur compounds were in agreement with the limited information reported about pineapple fruits of other regions. We report, for the first time in pineapple wines, the presence of significant concentrations of lactones, ketones, terpenes, norisoprenoids and a variety of volatile phenols. Eight native yeast strains were isolated from spontaneous batches. Further single-strain fermentations allowed us to characterise their suitability for commercial fermentation. Three native strains (Hanseniaspora opuntiae, H. uvarum and Meyerozyma guilliermondii) were selected with sensory potential to ferment pineapple fruits with increased flavour diversity. Results obtained here contribute to a better understanding of quality fermentation alternatives of this tropical fruit in subtropical regions. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. The microbial ecology of wine grape berries.

    Science.gov (United States)

    Barata, A; Malfeito-Ferreira, M; Loureiro, V

    2012-02-15

    Grapes have a complex microbial ecology including filamentous fungi, yeasts and bacteria with different physiological characteristics and effects upon wine production. Some species are only found in grapes, such as parasitic fungi and environmental bacteria, while others have the ability to survive and grow in wines, constituting the wine microbial consortium. This consortium covers yeast species, lactic acid bacteria and acetic acid bacteria. The proportion of these microorganisms depends on the grape ripening stage and on the availability of nutrients. Grape berries are susceptible to fungal parasites until véraison after which the microbiota of truly intact berries is similar to that of plant leaves, which is dominated by basidiomycetous yeasts (e.g. Cryptococcus spp., Rhodotorula spp. Sporobolomyces spp.) and the yeast-like fungus Aureobasidium pullulans. The cuticle of visually intact berries may bear microfissures and softens with ripening, increasing nutrient availability and explaining the possible dominance by the oxidative or weakly fermentative ascomycetous populations (e.g. Candida spp., Hanseniaspora spp., Metschnikowia spp., Pichia spp.) approaching harvest time. When grape skin is clearly damaged, the availability of high sugar concentrations on the berry surface favours the increase of ascomycetes with higher fermentative activity like Pichia spp. and Zygoascus hellenicus, including dangerous wine spoilage yeasts (e.g. Zygosaccharomyces spp., Torulaspora spp.), and of acetic acid bacteria (e.g. Gluconobacter spp., Acetobacter spp.). The sugar fermenting species Saccharomyces cerevisiae is rarely found on unblemished berries, being favoured by grape damage. Lactic acid bacteria are minor partners of grape microbiota and while being the typical agent of malolactic fermentation, Oenococcus oeni has been seldom isolated from grapes in the vineyard. Environmental ubiquitous bacteria of the genus Enterobacter spp., Enterococcus spp., Bacillus spp

  4. Genome Sequence of Australian Indigenous Wine Yeast Torulaspora delbrueckii COFT1 Using Nanopore Sequencing.

    Science.gov (United States)

    Tondini, Federico; Jiranek, Vladimir; Grbin, Paul R; Onetto, Cristobal A

    2018-04-26

    Here, we report the first sequenced genome of an indigenous Australian wine isolate of Torulaspora delbrueckii using the Oxford Nanopore MinION and Illumina HiSeq sequencing platforms. The genome size is 9.4 Mb and contains 4,831 genes. Copyright © 2018 Tondini et al.

  5. Ethanol-Independent Biofilm Formation by a Flor Wine Yeast Strain of Saccharomyces cerevisiae▿

    Science.gov (United States)

    Zara, Severino; Gross, Michael K.; Zara, Giacomo; Budroni, Marilena; Bakalinsky, Alan T.

    2010-01-01

    Flor strains of Saccharomyces cerevisiae form a biofilm on the surface of wine at the end of fermentation, when sugar is depleted and growth on ethanol becomes dependent on oxygen. Here, we report greater biofilm formation on glycerol and ethyl acetate and inconsistent formation on succinic, lactic, and acetic acids. PMID:20435772

  6. Ethanol-independent biofilm formation by a flor wine yeast strain of Saccharomyces cerevisiae.

    Science.gov (United States)

    Zara, Severino; Gross, Michael K; Zara, Giacomo; Budroni, Marilena; Bakalinsky, Alan T

    2010-06-01

    Flor strains of Saccharomyces cerevisiae form a biofilm on the surface of wine at the end of fermentation, when sugar is depleted and growth on ethanol becomes dependent on oxygen. Here, we report greater biofilm formation on glycerol and ethyl acetate and inconsistent formation on succinic, lactic, and acetic acids.

  7. Yeasts in foods and beverages: impact on product quality and safety.

    Science.gov (United States)

    Fleet, Graham H

    2007-04-01

    The role of yeasts in food and beverage production extends beyond the well-known bread, beer and wine fermentations. Molecular analytical technologies have led to a major revision of yeast taxonomy, and have facilitated the ecological study of yeasts in many other products. The mechanisms by which yeasts grow in these ecosystems and impact on product quality can now be studied at the level of gene expression. Their growth and metabolic activities are moderated by a network of strain and species interactions, including interactions with bacteria and other fungi. Some yeasts have been developed as agents for the biocontrol of food spoilage fungi, and others are being considered as novel probiotic organisms. The association of yeasts with opportunistic infections and other adverse responses in humans raises new issues in the field of food safety.

  8. Molecular characterization and technological properties of wine yeasts isolated during spontaneous fermentation of Vitis vinifera L.cv. Narince grape must grown in ancient wine making area Tokat, Anatolia

    Directory of Open Access Journals (Sweden)

    Çelik Zeynep Dilan

    2017-01-01

    Full Text Available Narince is a native white grape variety of Vitis vinifera L grown in Tokat and produces rich and balanced wines often with a greenish yellow tint and delicate fruity flavour. Fermentation by indigenous yeasts may produce wines with complex oenological properties that are unique to specific region. In this study yeast population during alcoholic fermentation of Narince was investigated. Yeasts were identified by PCR-RFLP analysis of the 5.8 ITS rRNA region and sequence information for the D1/D2 domains of the 26S gene. Eight different species belonging to nine genera were identified as: Hanseniaspora uvarum, Hansenispora guilliermondii, Pichia kluyveri, Metschnikowiaspp., Pichia occidentalis, Torulaspora delbrueckii, Candida zemplinina, Lachancea thermotolerance and Saccharomyces cerevisiae. Hanseniaspora guilliermondii, Metschnikowiaspp., Pichia occidentalis and Pichia kluyveri were identified only in the early stage of fermentation. Selected yeasts tested for their physiological traits, ethanol, SO2, temperature, pH tolerance, H2S production, killer and enzymatic activity, fermentation rate, flocculation characteristic, foam, volatile acid and volatile compounds production. Among the yeasts, one,Lachancea thermotolerance and four Saccharomyces cerevisiae strain showed remarkable technological properties and results were compared with those obtained by using commercial starter culture.

  9. THE INFLUENCE OF THIAMINE IN THE FERMENTATION OF THE WINE YEASTS

    Directory of Open Access Journals (Sweden)

    Ovidiu Tita

    2011-12-01

    Full Text Available Due to the enzymatic equipment, the yeast cell produces alcoholic fermentation by the meaning of a zimazic complex which catalyzes in different stages the redox processes of the carbohydrates, which are able to ferment, ultimately leading to ethanol. The fermentation rate is an exponential function being influenced by the cells concentration in the development environment and the starter cultures of micro-organisms. Most of the yeast strains do ferment some substrates rich in hexosanes and oligoglucides: sucrose, maltose, raffinose, lactose and celobiose. The biomass quantity may be increased in various ways. An important aspect in the increasing of the multiplication rate of the yeast cells is the determination of the optimum growing conditions. Some kinetic dependencies, mono and multi-factorial, have been observed; they describe the impact of the concentration of the base components in the nutrient environment, temperature, pH, mixing intensity on the multiplication rate of the yeasts.

  10. Lachancea lanzarotensis sp. nov., an ascomycetous yeast isolated from grapes and wine fermentation in Lanzarote, Canary Islands.

    Science.gov (United States)

    González, Sara S; Alcoba-Flórez, Julia; Laich, Federico

    2013-01-01

    During the characterization of the microbiota biodiversity associated with grapes and wineries in different bioclimatic conditions of the Canary Islands (Spain), a novel yeast species was isolated from Lanzarote, the driest wine-producing region of the archipelago. Seven strains isolated from grapes, microvinifications and wineries are described. Sequence analysis of the D1/D2 domain of the LSU rDNA gene and 5.8S-ITS regions revealed that the isolates were phylogenetically a member of the genus Lachancea and are closely related to Lachancea meyersii NRRL Y-27269(T) and Lachancea nothofagi NRRL Y-48670(T). On the basis of morphological, biochemical and physiological characterization and phylogenetic analysis, a novel ascosporogenous yeast species, Lachancea lanzarotensis sp. nov., is proposed. The type strain is L2C-15(T) ( = CBS 12615(T) = CECT 13066(T)) which was isolated from grape berries of Vitis vinifera L. cv. Listán Negro red grape variety in Tinajo, Lanzarote. The MycoBank no. is MB 801390.

  11. Engineering a Saccharomyces cerevisiae wine yeast that exhibits reduced ethanol production during fermentation under controlled microoxygenation conditions.

    Science.gov (United States)

    Heux, Stéphanie; Sablayrolles, Jean-Marie; Cachon, Rémy; Dequin, Sylvie

    2006-09-01

    We recently showed that expressing an H(2)O-NADH oxidase in Saccharomyces cerevisiae drastically reduces the intracellular NADH concentration and substantially alters the distribution of metabolic fluxes in the cell. Although the engineered strain produces a reduced amount of ethanol, a high level of acetaldehyde accumulates early in the process (1 g/liter), impairing growth and fermentation performance. To overcome these undesirable effects, we carried out a comprehensive analysis of the impact of oxygen on the metabolic network of the same NADH oxidase-expressing strain. While reducing the oxygen transfer rate led to a gradual recovery of the growth and fermentation performance, its impact on the ethanol yield was negligible. In contrast, supplying oxygen only during the stationary phase resulted in a 7% reduction in the ethanol yield, but without affecting growth and fermentation. This approach thus represents an effective strategy for producing wine with reduced levels of alcohol. Importantly, our data also point to a significant role for NAD(+) reoxidation in controlling the glycolytic flux, indicating that engineered yeast strains expressing an NADH oxidase can be used as a powerful tool for gaining insight into redox metabolism in yeast.

  12. Selection of 80 newly isolated autochthonous yeast strains from the Tikveš region of Macedonia and their impact on the quality of red wines produced from Vranec and Cabernet Sauvignon grape varieties.

    Science.gov (United States)

    Ilieva, Fidanka; Kostadinović Veličkovska, Sanja; Dimovska, Violeta; Mirhosseini, Hamed; Spasov, Hristo

    2017-02-01

    The main objectives of this study were to (i) isolate newly autochthonous yeast strains from the Tikveš region of Macedonia and (ii) test their impact on the quality of red wines from Vranec and Cabernet Sauvignon grape varieties. The newly isolated yeast strains were obtained by spontaneous fermentation of grape must from Vranec and Cabernet Sauvignon varieties collected from ten different micro-regions in Macedonia. The grapevines from both varieties grown in "Barovo" micro-region were the richest sources of yeast strains. In addition, the molecular identification and typing of strains were also carried out. The monomeric anthocyanins, polyphenolic content and other oenochemical characteristics of the wines were also compared with the wines from commercial yeast strain "SiHa". The Vranec wine from yeast strain F-8 and Cabernet Sauvignon wine from yeast strain F-20 had significantly (p<0.05) higher concentrations of monomeric anthocyanins and total phenolic compounds than other wines. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Optimising the inactivation of grape juice spoilage organisms by pulse electric fields.

    Science.gov (United States)

    Marsellés-Fontanet, A Robert; Puig, Anna; Olmos, Paola; Mínguez-Sanz, Santiago; Martín-Belloso, Olga

    2009-04-15

    The effect of some pulsed electric field (PEF) processing parameters (electric field strength, pulse frequency and treatment time), on a mixture of microorganisms (Kloeckera apiculata, Saccharomyces cerevisiae, Lactobacillus plantarum, Lactobacillus hilgardii and Gluconobacter oxydans) typically present in grape juice and wine were evaluated. An experimental design based on response surface methodology (RSM) was used and results were also compared with those of a factorially designed experiment. The relationship between the levels of inactivation of microorganisms and the energy applied to the grape juice was analysed. Yeast and bacteria were inactivated by the PEF treatments, with reductions that ranged from 2.24 to 3.94 log units. All PEF parameters affected microbial inactivation. Optimal inactivation of the mixture of spoilage microorganisms was predicted by the RSM models at 35.0 kV cm(-1) with 303 Hz pulse width for 1 ms. Inactivation was greater for yeasts than for bacteria, as was predicted by the RSM. The maximum efficacy of the PEF treatment for inactivation of microorganisms in grape juice was observed around 1500 MJ L(-1) for all the microorganisms investigated. The RSM could be used in the fruit juice industry to optimise the inactivation of spoilage microorganisms by PEF.

  14. Spoilage yeasts in Patagonian winemaking: molecular and physiological features of Pichia guilliermondii indigenous isolates Levaduras contaminantes en vinos patagónicos: características moleculares y fisiológicas de los aislamientos indígenas de Picchia guilliermondii

    Directory of Open Access Journals (Sweden)

    C. A. Lopes

    2009-09-01

    Full Text Available Yeasts belonging to the genus Dekkera/Brettanomyces, especially the species Dekkera bruxellensis, have long been associated with the production of volatile phenols responsible for off-flavour in wines. According to recent reports, the species Pichia guilliermondii could also produce these compounds at the initial stages of fermentation. Based on the abundance of P. guilliermondii in Patagonian winemaking, we decided to study the relevance of indigenous isolates belonging to this species as wine spoilage yeast. Twenty-three indigenous isolates obtained from grape surfaces and red wine musts were analyzed in their capacity to produce volatile phenols on grape must. The relationship between molecular Random Amplified Polymorphic DNA (RAPD and physiological (killer biotype patterns detected in indigenous populations of P. guilliermondii and volatile phenol production was also evaluated. Different production levels of 4-ethylphenol, 4-vinylguaiacol and 4-ethylguaiacol were detected among the isolates; however, the values were always lower than those produced by the D. bruxellensis reference strain in the same conditions. High levels of 4-vinylphenol were detected among P. guilliermondii indigenous isolates. The combined use of RAPD and killer biotype allowed us to identify the isolates producing the highest volatile phenol levels.Las levaduras del género Dekkera/Brettanomyces, sobre todo la especie Dekkera bruxellensis, siempre han sido asociadas con la producción de fenoles volátiles responsables de aromas desagradables en los vinos. Recientemente, se ha demostrado que la especie Pichia guilliermondii también es capaz de producir estos compuestos, particularmente durante las etapas iniciales de la fermentación. Dada la abundancia de P. guilliermondii en las bodegas de la Patagonia, se decidió evaluar la importancia de algunos aislamientos indígenas de esta especie como levaduras alterantes de vinos regionales. Se evaluó la capacidad de

  15. Quality and Composition of Red Wine Fermented with Schizosaccharomyces pombe as Sole Fermentative Yeast, and in Mixed and Sequential Fermentations with Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Felipe Palomero

    2014-01-01

    Full Text Available This work examines the physiology of Schizosaccharomyces pombe (represented by strain 938 in the production of red wine, as the sole fermentative yeast, and in mixed and sequential fermentations with Saccharomyces cerevisiae 796. For further comparison, fermentations in which Saccharomyces cerevisiae was the sole fermentative yeast were also performed; in these fermentations a commercial lactic acid bacterium was used to perform malolactic fermentation once alcoholic fermentation was complete (unlike S. cerevisiae, the Sc. pombe performs maloalcoholic fermentation and therefore removes malic acid without such help. Relative density, acetic, malic and pyruvic acid concentrations, primary amino nitrogen and urea concentrations, and pH of the musts were measured over the entire fermentation period. In all fermentations in which Sc. pombe 938 was involved, nearly all the malic acid was consumed from an initial concentration of 5.5 g/L, and moderate acetic acid concentrations below 0.4 g/L were formed. The urea content of these wines was notably lower, showing a tenfold reduction when compared with those that were made with S. cerevisiae 796 alone. The sensorial properties of the different final wines varied widely. The wines fermented with Sc. pombe 938 had maximum aroma intensity and quality, and they were preferred by the tasters.

  16. Reduction of oxidative cellular damage by overexpression of the thioredoxin TRX2 gene improves yield and quality of wine yeast dry active biomass

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    Ros Joaquim

    2010-02-01

    Full Text Available Abstract Background Wine Saccharomyces cerevisiae strains, adapted to anaerobic must fermentations, suffer oxidative stress when they are grown under aerobic conditions for biomass propagation in the industrial process of active dry yeast production. Oxidative metabolism of sugars favors high biomass yields but also causes increased oxidation damage of cell components. The overexpression of the TRX2 gene, coding for a thioredoxin, enhances oxidative stress resistance in a wine yeast strain model. The thioredoxin and also the glutathione/glutaredoxin system constitute the most important defense against oxidation. Trx2p is also involved in the regulation of Yap1p-driven transcriptional response against some reactive oxygen species. Results Laboratory scale simulations of the industrial active dry biomass production process demonstrate that TRX2 overexpression increases the wine yeast final biomass yield and also its fermentative capacity both after the batch and fed-batch phases. Microvinifications carried out with the modified strain show a fast start phenotype derived from its enhanced fermentative capacity and also increased content of beneficial aroma compounds. The modified strain displays an increased transcriptional response of Yap1p regulated genes and other oxidative stress related genes. Activities of antioxidant enzymes like Sod1p, Sod2p and catalase are also enhanced. Consequently, diminished oxidation of lipids and proteins is observed in the modified strain, which can explain the improved performance of the thioredoxin overexpressing strain. Conclusions We report several beneficial effects of overexpressing the thioredoxin gene TRX2 in a wine yeast strain. We show that this strain presents an enhanced redox defense. Increased yield of biomass production process in TRX2 overexpressing strain can be of special interest for several industrial applications.

  17. The effect of increased branched-chain amino acid transaminase activity in yeast on the production of higher alcohols and on the flavour profiles of wine and distillates.

    Science.gov (United States)

    Lilly, Mariska; Bauer, Florian F; Styger, Gustav; Lambrechts, Marius G; Pretorius, Isak S

    2006-08-01

    In Saccharomyces cerevisiae, branched-chain amino acid transaminases (BCAATases) are encoded by the BAT1 and BAT2 genes. BCAATases catalyse the transfer of amino groups between those amino acids and alpha-keto-acids. alpha-Keto-acids are precursors for the biosynthesis of higher alcohols, which significantly influence the aroma and flavour of yeast-derived fermentation products. The objective of this study was to investigate the influence of BAT-gene expression on general yeast physiology, on aroma and flavour compound formation and on the sensory characteristics of wines and distillates. For this purpose, the genes were overexpressed and deleted in a laboratory strain, BY4742, and overexpressed in an industrial wine yeast strain, VIN13. The data show that, with the exception of a slow growth phenotype observed for the BAT1 deletion strain, the fermentation behaviour of the strains was unaffected by the modifications. The chemical and sensory analysis of fermentation products revealed a strong correction between BAT gene expression and the formation of many aroma compounds. The data suggest that the adjustment of BAT gene expression could play an important role in assisting winemakers in their endeavour to produce wines with specific flavour profiles.

  18. Indigenous and inoculated yeast fermentation of gabiroba (Campomanesia pubescens) pulp for fruit wine production.

    Science.gov (United States)

    Duarte, Whasley Ferreira; Dias, Disney Ribeiro; de Melo Pereira, Gilberto Vinicius; Gervásio, Ivani Maria; Schwan, Rosane Freitas

    2009-04-01

    The objectives of this study were to evaluate the potential of gabiroba Campomanesia pubescens (DC) O. Berg in the production of a beverage fermented using selected and wild yeasts from indigenous fermentation, analyze the volatile compounds profile present during the process of fermentation, and evaluate the sensory quality of the final beverage produced. Throughout the process of fermentation, when Saccharomyces cerevisiae UFLA CA 1162 was inoculated, there were stable viable populations around 9 log cells ml(-1). During indigenous fermentation, yeast population increased from 3.7 log CFU ml(-1) to 8.1 log CFU ml(-1) after 14 days. The diversity and dynamics of the yeast population during indigenous fermentation observed by PFGE analysis showed five different karyotyping profiles in the first days of fermentation. After the seventh day, there was a higher frequency of a similar S. cerevisiae profile. The yeast non-Saccharomyces were identified by sequencing of the ITS region as Candida quercitrusa and Issatchenkia terricola. Inoculated fermentations yielded a higher amount of alcohol than indigenous ones, indicating the efficiency of selected strains. There was also a greater concentration of higher alcohols, which are usually responsible for the flavor found in alcoholic beverages. Based on the characteristics of the pulp and acceptance in the sensory analysis, gabiroba fruits showed good potential for use in the production of fermented beverage.

  19. Combine Use of Selected Schizosaccharomyces pombe andLachancea thermotolerans Yeast Strains as an Alternative to theTraditional Malolactic Fermentation in Red Wine Production

    Directory of Open Access Journals (Sweden)

    Ángel Benito

    2015-05-01

    Full Text Available Most red wines commercialized in the market use the malolactic fermentationprocess in order to ensure stability from a microbiological point of view. In this secondfermentation, malic acid is converted into L-lactic acid under controlled setups. Howeverthis process is not free from possible collateral effects that on some occasions produceoff-flavors, wine quality loss and human health problems. In warm viticulture regions suchas the south of Spain, the risk of suffering a deviation during the malolactic fermentationprocess increases due to the high must pH. This contributes to produce wines with highvolatile acidity and biogenic amine values. This manuscript develops a new red winemakingmethodology that consists of combining the use of two non-Saccharomyces yeast strains asan alternative to the traditional malolactic fermentation. In this method, malic acid is totallyconsumed by Schizosaccharomyces pombe, thus achieving the microbiological stabilizationobjective, while Lachancea thermotolerans produces lactic acid in order not to reduce andeven increase the acidity of wines produced from low acidity musts. This technique reducesthe risks inherent to the malolactic fermentation process when performed in warm regions.The result is more fruity wines that contain less acetic acid and biogenic amines than thetraditional controls that have undergone the classical malolactic fermentation.

  20. Effects of using mixed wine yeast cultures in the production of Chardonnay wines Efecto del uso de cultivos mixtos de levaduras en la producción de vinos Chardonnay

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    V. García

    2010-09-01

    Full Text Available The effect of using mixed cultures of non-Saccharomyces and Saccharomyces cerevisiae yeasts in the physicochemical and sensory qualities of the wines were analyzed in this study. Based on growth curves, sugar consumption and glycerol production in synthetic must, Candida membranifaciens L1805 was selected from a group of four Candidas spp. isolates from Chile and Argentina. This yeast was subsequently used in combination with S. cerevisiae in Chardonnay must. A monoculture of S. cerevisiae was used as control. The wines fermented with mixed cultures had lower volatile acidity and ethanol concentration than the control. Furthermore, the chromatographic analysis showed that the wines from mixed cultures presented differences in the concentration of esters and propanol. These characteristics positively influenced the sensory qualities of the wines produced with mixed cultures, which was reflected in the preference for these wines by a panel of enologists. This study shows that the use of non-Saccharomyces yeasts could be a strategy to obtain distinctive wines using the native microorganisms from each winemaking area.En este estudio se analizó el efecto del uso de cultivos mixtos de levaduras no-Saccharomyces y Saccharomyces cerevisiae en las cualidades fisicoquímicas y sensoriales de los vinos. Candida membranifaciens L1805 fue elegida de un grupo de cuatro Candida spp. aisladas de Chile y Argentina, sobre la base de las curvas de crecimiento, el consumo de azúcar y la producción de glicerol en mosto sintético. Posteriormente, esta levadura fue usada en cultivo mixto con S. cerevisiae en mosto Chardonnay. Como control se utilizó un monocultivo de S. cerevisiae. Los vinos producidos por cultivos mixtos tuvieron menor acidez volátil y producción de etanol que los correspondientes al control. Los análisis cromatográficos mostraron que estos vinos presentaron diferencias en la concentración de ésteres y de propanol. Estas caracter

  1. A multi-phase approach to select new wine yeast strains with enhanced fermentative fitness and glutathione production.

    Science.gov (United States)

    Bonciani, Tommaso; De Vero, Luciana; Mezzetti, Francesco; Fay, Justin C; Giudici, Paolo

    2018-03-01

    The genetic improvement of winemaking yeasts is a virtually infinite process, as the design of new strains must always cope with varied and ever-evolving production contexts. Good wine yeasts must feature both good primary traits, which are related to the overall fermentative fitness of the strain, and secondary traits, which provide accessory features augmenting its technological value. In this context, the superiority of "blind," genetic improvement techniques, as those based on the direct selection of the desired phenotype without prior knowledge of the genotype, was widely proven. Blind techniques such as adaptive evolution strategies were implemented for the enhancement of many traits of interest in the winemaking field. However, these strategies usually focus on single traits: this possibly leads to genetic tradeoff phenomena, where the selection of enhanced secondary traits might lead to sub-optimal primary fermentation traits. To circumvent this phenomenon, we applied a multi-step and strongly directed genetic improvement strategy aimed at combining a strong fermentative aptitude (primary trait) with an enhanced production of glutathione (secondary trait). We exploited the random genetic recombination associated to a library of 69 monosporic clones of strain UMCC 855 (Saccharomyces cerevisiae) to search for new candidates possessing both traits. This was achieved by consecutively applying three directional selective criteria: molybdate resistance (1), fermentative aptitude (2), and glutathione production (3). The strategy brought to the selection of strain 21T2-D58, which produces a high concentration of glutathione, comparable to that of other glutathione high-producers, still with a much greater fermentative aptitude.

  2. Proteomic and metabolomic study of wine yeasts in free and immobilized formats, subjected to different stress conditions

    OpenAIRE

    Moreno-García, Jaime

    2017-01-01

    The aroma of wine is the first sensory perception that affects its quality. The knowledge acquired to date ensures that the unique aroma of a specific wine is the result of the sensation that in our sense of smell cause the molecules of more than 800 volatile compounds present in the hydroalcoholic solution that is the wine.These compounds come from the grapes, the prefermentative treatments, the alcoholic fermentation and the aging or preservation of the wine. It is a...

  3. Metabolic and transcriptomic response of the wine yeast Saccharomyces cerevisiae strain EC1118 after an oxygen impulse under carbon-sufficient, nitrogen-limited fermentative conditions.

    Science.gov (United States)

    Orellana, Marcelo; Aceituno, Felipe F; Slater, Alex W; Almonacid, Leonardo I; Melo, Francisco; Agosin, Eduardo

    2014-05-01

    During alcoholic fermentation, Saccharomyces cerevisiae is exposed to continuously changing environmental conditions, such as decreasing sugar and increasing ethanol concentrations. Oxygen, a critical nutrient to avoid stuck and sluggish fermentations, is only discretely available throughout the process after pump-over operation. In this work, we studied the physiological response of the wine yeast S. cerevisiae strain EC1118 to a sudden increase in dissolved oxygen, simulating pump-over operation. With this aim, an impulse of dissolved oxygen was added to carbon-sufficient, nitrogen-limited anaerobic continuous cultures. Results showed that genes related to mitochondrial respiration, ergosterol biosynthesis, and oxidative stress, among other metabolic pathways, were induced after the oxygen impulse. On the other hand, mannoprotein coding genes were repressed. The changes in the expression of these genes are coordinated responses that share common elements at the level of transcriptional regulation. Beneficial and detrimental effects of these physiological processes on wine quality highlight the dual role of oxygen in 'making or breaking wines'. These findings will facilitate the development of oxygen addition strategies to optimize yeast performance in industrial fermentations. © 2014 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  4. Extracellular Phytase Production by the Wine Yeast S. cerevisiae (Finarome Strain) during Submerged Fermentation.

    Science.gov (United States)

    Kłosowski, Grzegorz; Mikulski, Dawid; Jankowiak, Oliwia

    2018-04-08

    One of the key steps in the production of phytases of microbial origin is selection of culture parameters, followed by isolation of the enzyme and evaluation of its catalytic activity. It was found that conditions for S. cerevisiae yeast culture, strain Finarome, giving the reduction in phytic acid concentration of more than 98% within 24 h of incubation were as follows: pH 5.5, 32 °C, continuous stirring at 80 rpm, the use of mannose as a carbon source and aspartic acid as a source of nitrogen. The highest catalytic activity of the isolated phytase was observed at 37 °C, pH 4.0 and using phytate as substrate at concentration of 5.0 mM. The presence of ethanol in the medium at a concentration of 12% v / v reduces the catalytic activity to above 60%. Properties of phytase derived from S. cerevisiae yeast culture, strain Finarome, indicate the possibility of its application in the form of a cell's free crude protein isolate for the hydrolysis of phytic acid to improve the efficiency of alcoholic fermentation processes. Our results also suggest a possibility to use the strain under study to obtain a fusant derived with specialized distillery strains, capable of carrying out a highly efficient fermentation process combined with the utilization of phytates.

  5. Meat spoilage during distribution.

    Science.gov (United States)

    Nychas, George-John E; Skandamis, Panos N; Tassou, Chrysoula C; Koutsoumanis, Konstantinos P

    2008-01-01

    Meat spoilage during distribution can be considered as an ecological phenomenon that encompasses the changes of the available substrata (e.g., low molecular compounds), during the prevailing of a particular microbial association, the so-called specific spoilage organisms (SSO). In fact, spoilage of meat depends on an even smaller fraction of SSO, called ephemeral spoilage organisms (ESO). These ESO are the consequence of factors that dynamically persist or imposed during, e.g., processing, transportation and storage in the market. Meanwhile spoilage is a subjective judgment by the consumer, which may be influenced by cultural and economic considerations and background as well as by the sensory acuity of the individual and the intensity of the change. Indeed, when spoilage progresses, most consumers would agree that gross discoloration, strong off-odors, and the development of slime would constitute the main qualitative criteria for meat rejection. On the other hand, meat industry needs rapid analytical methods or tools for quantification of these indicators to determine the type of processing needed for their raw material and to predict remaining shelf life of their products. The need of an objective evaluation of meat spoilage is of great importance. The use of metabolomics as a potential tool for the evaluation of meat spoilage can be of great importance. The microbial association of meat should be monitored in parallel with the estimation of changes occurring in the production and/or assimilation of certain compounds would allow us to evaluate spoilage found or produced during the storage of meat under different temperatures as well as packaging conditions.

  6. Microbiological Spoilage of High-Sugar Products

    Science.gov (United States)

    Thompson, Sterling

    The high-sugar products discussed in this chapter are referred to as chocolate, sugar confectionery (non-chocolate), liquid sugars, sugar syrups, and honey. Products grouped in the sugar confectionery category include hard candy, soft/gummy candy, caramel, toffee, licorice, marzipan, creams, jellies, and nougats. A common intrinsic parameter associated with high-sugar products is their low water activity (a w), which is known to inhibit the growth of most spoilage and pathogenic bacteria. However, spoilage can occur as a result of the growth of osmophilic yeasts and xerophilic molds (Von Richter, 1912; Anand & Brown, 1968; Brown, 1976). The a w range for high-sugar products is between 0.20 and 0.80 (Banwart, 1979; Richardson, 1987; Lenovich & Konkel, 1992; ICMSF, 1998; Jay, Loessner, & Golden, 2005). Spoilage of products, such as chocolate-covered cherries, results from the presence of yeasts in the liquid sugar brine or the cherry. Generally, the spoiled product will develop leakers. The chocolate covering the cherry would not likely be a source of yeast contamination.

  7. Yeast Monitoring of Wine Mixed or Sequential Fermentations Made by Native Strains from D.O. “Vinos de Madrid” Using Real-Time Quantitative PCR

    Science.gov (United States)

    García, Margarita; Esteve-Zarzoso, Braulio; Crespo, Julia; Cabellos, Juan M.; Arroyo, Teresa

    2017-01-01

    There is an increasing trend toward understanding the impact of non-Saccharomyces yeasts on the winemaking process. Although Saccharomyces cerevisiae is the predominant species at the end of fermentation, it has been recognized that the presence of non-Saccharomyces species during alcoholic fermentation can produce an improvement in the quality and complexity of the final wines. A previous work was developed for selecting the best combinations between S. cerevisiae and five non-Saccharomyces (Torulaspora delbrueckii, Schizosaccharomyces pombe, Candida stellata, Metschnikowia pulcherrima, and Lachancea thermotolorans) native yeast strains from D.O. “Vinos de Madrid” at the laboratory scale. The best inoculation strategies between S. cerevisiae and non-Saccharomyces strains were chosen to analyze, by real-time quantitative PCR (qPCR) combined with the use of specific primers, the dynamics of inoculated populations throughout the fermentation process at the pilot scale using the Malvar white grape variety. The efficiency of the qPCR system was verified independently of the samples matrix, founding the inoculated yeast species throughout alcoholic fermentation. Finally, we can validate the positive effect of selected co-cultures in the Malvar wine quality, highlighting the sequential cultures of T. delbrueckii CLI 918/S. cerevisiae CLI 889 and C. stellata CLI 920/S. cerevisiae CLI 889 and, mixed and sequential cultures of L. thermotolerans 9-6C combined with S. cerevisiae CLI 889. PMID:29326669

  8. Yeast Monitoring of Wine Mixed or Sequential Fermentations Made by Native Strains from D.O. “Vinos de Madrid” Using Real-Time Quantitative PCR

    Directory of Open Access Journals (Sweden)

    Margarita García

    2017-12-01

    Full Text Available There is an increasing trend toward understanding the impact of non-Saccharomyces yeasts on the winemaking process. Although Saccharomyces cerevisiae is the predominant species at the end of fermentation, it has been recognized that the presence of non-Saccharomyces species during alcoholic fermentation can produce an improvement in the quality and complexity of the final wines. A previous work was developed for selecting the best combinations between S. cerevisiae and five non-Saccharomyces (Torulaspora delbrueckii, Schizosaccharomyces pombe, Candida stellata, Metschnikowia pulcherrima, and Lachancea thermotolorans native yeast strains from D.O. “Vinos de Madrid” at the laboratory scale. The best inoculation strategies between S. cerevisiae and non-Saccharomyces strains were chosen to analyze, by real-time quantitative PCR (qPCR combined with the use of specific primers, the dynamics of inoculated populations throughout the fermentation process at the pilot scale using the Malvar white grape variety. The efficiency of the qPCR system was verified independently of the samples matrix, founding the inoculated yeast species throughout alcoholic fermentation. Finally, we can validate the positive effect of selected co-cultures in the Malvar wine quality, highlighting the sequential cultures of T. delbrueckii CLI 918/S. cerevisiae CLI 889 and C. stellata CLI 920/S. cerevisiae CLI 889 and, mixed and sequential cultures of L. thermotolerans 9-6C combined with S. cerevisiae CLI 889.

  9. Interplay among Gcn5, Sch9 and mitochondria during chronological aging of wine yeast is dependent on growth conditions.

    Directory of Open Access Journals (Sweden)

    Cecilia Picazo

    Full Text Available Saccharomyces cerevisiae chronological life span (CLS is determined by a wide variety of environmental and genetic factors. Nutrient limitation without malnutrition, i.e. dietary restriction, expands CLS through the control of nutrient signaling pathways, of which TOR/Sch9 has proven to be the most relevant, particularly under nitrogen deprivation. The use of prototrophic wine yeast allows a better understanding of the role of nitrogen in longevity in natural and more demanding environments, such as grape juice fermentation. We previously showed that acetyltransferase Gcn5, a member of the SAGA complex, has opposite effects on CLS under laboratory and winemaking conditions, and is detrimental under the latter. Here we demonstrate that integrity of the SAGA complex is necessary for prolonged longevity, as its dismantling by SPT20 deletion causes a drop in CLS under both laboratory and winemaking conditions. The sch9Δ mutant is long-lived in synthetic SC medium, as expected, and the combined deletion of GCN5 partially suppresses this phenotype. However it is short-lived in grape juice, likely due to its low nitrogen/carbon ratio. Therefore, unbalance of nutrients can be more relevant for life span than total amounts of them. Deletion of RTG2, which codes for a protein associated with Gcn5 and is a component of the mitochondrial retrograde signal, and which communicates mitochondrial dysfunction to the nucleus, is detrimental under laboratory, but not under winemaking conditions, where respiration seems not so relevant for longevity. Transcription factor Rgm1 was found to be a novel CLS regulator Sch9-dependently.

  10. Efficiency of population-dependent sulfite against Brettanomyces bruxellensis in red wine.

    Science.gov (United States)

    Longin, Cédric; Degueurce, Claudine; Julliat, Frédérique; Guilloux-Benatier, Michèle; Rousseaux, Sandrine; Alexandre, Hervé

    2016-11-01

    Brettanomyces bruxellensis is considered as a spoilage yeast encountered mainly in red wine. It is able to reduce vinylphenols from phenolic acids to ethylphenols. These volatiles are responsible for the phenolic "Brett character" described as animal, farm, horse sweat and animal leather odors. Other molecules are responsible for organoleptic deviations described as "mousiness taint". SO 2 is the product most often used by winemakers to prevent B. bruxellensis growth. Usually, the recommended molecular dose of SO 2 (active SO 2 , mSO 2 ) is highly variable, from 0.3 to 0.8mg/L. But these doses do not take into account differences of strain resistance to sulfites or population levels. Moreover, SO 2 is known as a chemical stressor inducing a viable but nonculturable (VBNC) state of B. bruxellensis. These cells, which are non-detectable by plate counting, can lead to new contamination when the amount of sulfite decreases over time. Consequently, we first assessed the effect of SO 2 levels in red wine on two strains with phenotypically different sulfite resistances. Then, we studied the relationship between amounts of SO 2 (0, 0.5, 0.9 and 1.1mg/L active SO 2 ) and population levels (10 3 , 10 4 and 10 5 cells/mL) in red wine. Yeasts were enumerated by both plate counting and flow cytometry over time using viability dye. Our results showed different SO 2 resistances according to the strain used. A relationship between yeast population level and SO 2 resistance was demonstrated: the higher the yeast concentration, the lower the efficiency of SO 2 . Under certain conditions, the VBNC state of B. bruxellensis was highlighted in red wine. Yeasts in this VBNC state did not produce 4-EP. Moreover, cells became culturable again over time. All these results provide new information enabling better management of sulfite addition during wine aging. Copyright © 2016. Published by Elsevier Ltd.

  11. Influence of Fermentation Temperature, Yeast Strain, and Grape Juice on the Aroma Chemistry and Sensory Profile of Sauvignon Blanc Wines.

    Science.gov (United States)

    Deed, Rebecca C; Fedrizzi, Bruno; Gardner, Richard C

    2017-10-11

    Sauvignon blanc wine, balanced by herbaceous and tropical aromas, is fermented at low temperatures (10-15 °C). Anecdotal accounts from winemakers suggest that cold fermentations produce and retain more "fruity" aroma compounds; nonetheless, studies have not confirmed why low temperatures are optimal for Sauvignon blanc. Thirty-two aroma compounds were quantitated from two Marlborough Sauvignon blanc juices fermented at 12.5 and 25 °C, using Saccharomyces cerevisiae strains EC1118, L-1528, M2, and X5. Fourteen compounds were responsible for driving differences in aroma chemistry. The 12.5 °C-fermented wines had lower 3-mercaptohexan-1-ol (3MH) and higher alcohols but increased fruity acetate esters. However, a sensory panel did not find a significant difference between fruitiness in 75% of wine pairs based on fermentation temperature, in spite of chemical differences. For wine pairs with significant differences (25%), the 25 °C-fermented wines were fruitier than the 12.5 °C-fermented wines, with high fruitiness associated with 3MH. We propose that the benefits of low fermentation temperatures are not derived from increased fruitiness but a better balance between fruitiness and greenness. Even so, since 75% of wines showed no significant difference, higher fermentation temperatures could be utilized without detriment, lowering costs for the wine industry.

  12. Effects of rehydration nutrients on H2S metabolism and formation of volatile sulfur compounds by the wine yeast VL3.

    Science.gov (United States)

    Winter, Gal; Henschke, Paul A; Higgins, Vincent J; Ugliano, Maurizio; Curtin, Chris D

    2011-11-02

    In winemaking, nutrient supplementation is a common practice for optimising fermentation and producing quality wine. Nutritionally suboptimal grape juices are often enriched with nutrients in order to manipulate the production of yeast aroma compounds. Nutrients are also added to active dry yeast (ADY) rehydration media to enhance subsequent fermentation performance. In this study we demonstrate that nutrient supplementation at rehydration also has a significant effect on the formation of volatile sulfur compounds during wine fermentations. The concentration of the 'fruity' aroma compounds, the polyfunctional thiols 3-mercaptohexan-1-ol (3MH) and 3-mercaptohexyl acetate (3MHA), was increased while the concentration of the 'rotten egg' aroma compound, hydrogen sulfide (H2S), was decreased. Nutrient supplementation of the rehydration media also changed the kinetics of H2S production during fermentation by advancing onset of H2S production. Microarray analysis revealed that this was not due to expression changes within the sulfate assimilation pathway, which is known to be a major contributor to H2S production. To gain insight into possible mechanisms responsible for this effect, a component of the rehydration nutrient mix, the tri-peptide glutathione (GSH) was added at rehydration and studied for its subsequent effects on H2S formation. GSH was found to be taken up during rehydration and to act as a source for H2S during the following fermentation. These findings represent a potential approach for managing sulfur aroma production through the use of rehydration nutrients.

  13. Assessing genetic diversity among Brettanomyces yeasts by DNA fingerprinting and whole-genome sequencing.

    Science.gov (United States)

    Crauwels, Sam; Zhu, Bo; Steensels, Jan; Busschaert, Pieter; De Samblanx, Gorik; Marchal, Kathleen; Willems, Kris A; Verstrepen, Kevin J; Lievens, Bart

    2014-07-01

    Brettanomyces yeasts, with the species Brettanomyces (Dekkera) bruxellensis being the most important one, are generally reported to be spoilage yeasts in the beer and wine industry due to the production of phenolic off flavors. However, B. bruxellensis is also known to be a beneficial contributor in certain fermentation processes, such as the production of certain specialty beers. Nevertheless, despite its economic importance, Brettanomyces yeasts remain poorly understood at the genetic and genomic levels. In this study, the genetic relationship between more than 50 Brettanomyces strains from all presently known species and from several sources was studied using a combination of DNA fingerprinting techniques. This revealed an intriguing correlation between the B. bruxellensis fingerprints and the respective isolation source. To further explore this relationship, we sequenced a (beneficial) beer isolate of B. bruxellensis (VIB X9085; ST05.12/22) and compared its genome sequence with the genome sequences of two wine spoilage strains (AWRI 1499 and CBS 2499). ST05.12/22 was found to be substantially different from both wine strains, especially at the level of single nucleotide polymorphisms (SNPs). In addition, there were major differences in the genome structures between the strains investigated, including the presence of large duplications and deletions. Gene content analysis revealed the presence of 20 genes which were present in both wine strains but absent in the beer strain, including many genes involved in carbon and nitrogen metabolism, and vice versa, no genes that were missing in both AWRI 1499 and CBS 2499 were found in ST05.12/22. Together, this study provides tools to discriminate Brettanomyces strains and provides a first glimpse at the genetic diversity and genome plasticity of B. bruxellensis. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  14. Country-wine making from Eembe fruit (Berchemia discolor) of ...

    African Journals Online (AJOL)

    Country-wine was made from dried Eembe fruit purchased from Katima Mulilo open market using commercial wine yeast. The fruit produced a wine with 8.6% alcohol content when no sugar was added. Fermentation to produce the wine was carried out at 22ºC. The clarity, aroma, colour and acceptability of the wine was ...

  15. Australian wine consumers’ acceptance of and attitudes toward the use of additives in wine and food production

    OpenAIRE

    Saltman Y; Johnson TE; Wilkinson KL; Bastian SEP

    2015-01-01

    Yaelle Saltman, Trent E Johnson, Kerry L Wilkinson, Susan EP Bastian Department of Wine and Food, School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, Adelaide, SA, Australia. Abstract: Additives are routinely used in food and wine production to enhance product quality and/or prevent spoilage. Compared with other industries, the wine industry is only permitted to use a limited number of additives. Whereas flavor additives are often used to intensify the aroma and f...

  16. Use of non-saccharomyces Torulaspora delbrueckii yeast strains in winemaking and brewing

    Directory of Open Access Journals (Sweden)

    Tataridis Panagiotis

    2013-01-01

    Full Text Available Selected Saccharomyces yeast strains have been used for more than 150 years in brewing and for several decades in winemaking. They are necessary in brewing because of the boiling of the wort, which results in the death of all yeast cells, with the exception of some Belgian style beers (ex. Lambic, where the wort is left to be colonized by indigenous yeast and bacteria from the environment and ferment naturally. In winemaking their use is also pertinent because they provide regular and timely fermentations, inhibit the growth of indigenous spoilage microorganisms and contribute to the desired sensory characters. Even though the use of selected Saccharomyces strains provides better quality assurance in winemaking in comparison to the unknown microbial consortia in the must, it has been debated for a long time now whether the use of selected industrial Saccharomyces strains results in wines with less sensory complexity and “terroir” character. In previous decades, non-Saccharomyces yeasts were mainly considered as spoilage/problematic yeast, since they exhibited low fermentation ability and other negative traits. In the last decades experiments have shown that there are some non-Saccharomyces strains (Candida, Pichia, Kluyveromyces, Torulaspora, etc which, even though they are not able to complete the fermentation they can still be used in sequential inoculation-fermentation with Saccharomyces to increase sensory complexity of the wines. Through fermentation in a laboratory scale, we have observed that the overall effects of selected Torulaspora delbrueckii yeast strains, is highly positive, leading to products with pronounced sensory complexity and floral/fruity aroma in winemaking and brewing.

  17. The Microbial Diversity of Sherry Wines

    Directory of Open Access Journals (Sweden)

    Gustavo Cordero-Bueso

    2018-03-01

    Full Text Available The principal role of wine yeast is to transform efficiently the grape-berries’ sugars to ethanol, carbon dioxide, and other metabolites, without the production of off-flavors. Wine yeast strains are able to ferment musts, while other commercial or laboratory strains fail to do so. The genetic differences that characterize wine yeast strains in contrast to the biological ageing of the veil-forming yeasts in Sherry wines are poorly understood. Saccharomyces cerevisiae strains frequently exhibit rather specific phenotypic features needed for adaptation to a special environment, like fortified wines with ethanol up to 15% (v/v, known as Sherry wines. Factors that affect the correct development of the veil of flor during ageing are also reviewed, along with the related aspects of wine composition, biofilm formation processes, and yeast autolysis. This review highlights the importance of yeast ecology and yeast metabolic reactions in determining Sherry wine quality and the wealth of untapped indigenous microorganisms co-existing with the veil-forming yeast strains. It covers the complexity of the veil forming wine yeasts’ genetic features, and the genetic techniques often used in strain selection and monitoring during fermentation or biological ageing. Finally, the outlook for new insights to protect and to maintain the microbiota of the Sherry wines will be discussed.

  18. Prevention of the appearance of light-struck taste in white wine / Prevenzione della comparsa del gusto di luce nel vino bianco

    Directory of Open Access Journals (Sweden)

    Fracassetti Daniela

    2016-01-01

    Full Text Available The light-struck taste is a defect of bottled white wine due to the light exposure and involving the riboflavin (RF, as a photosensitizer, and methionine. The reaction pathways lead to the formation of volatile sulfur compounds, methanethiol and dimethyldisulphide, conferring cabbage-like aromas. The development of this defect is limited at low RF concentrations. In this study, the yeast-mediated release of RF, RF degradation kinetics in model solution and white wine, and RF removal by using insoluble adjuvants were investigated. The results showed the RF release was a strain-dependent property and the fermentation rate did not affect the RF synthesis. The RF degradation followed a 1st order kinetic in both model solution and white wine in which the degradation rate was halved. Among the adjuvants tested, bentonite and active charcoal were the most effective in RF removal and higher concentrations were needed for effectively treating white wine. The selection of low RF-producing yeasts and the treatment with active charcoal could represent useful tools to avoid the white wine spoilage during the shelf-life.

  19. Enological Tannin Effect on Red Wine Color and Pigment Composition and Relevance of the Yeast Fermentation Products

    OpenAIRE

    Ignacio García-Estévez; Cristina Alcalde-Eon; Víctor Puente; M. Teresa Escribano-Bailón

    2017-01-01

    Enological tannins are widely used in the winemaking process either to improve different wine characteristics (color stability, among others) or to compensate for low tannin levels. In this work, the influence of the addition of two different enological tannins, mainly composed of hydrolysable (ellagitannins) and condensed tannins, on the evolution of color and pigment composition of two different types of model systems containing the five main grape anthocyanins was studied. In addition, the...

  20. Adaptability of the Saccharomyces cerevisiae yeasts to wine fermentation conditions relies on their strong ability to consume nitrogen

    Science.gov (United States)

    2018-01-01

    Saccharomyces cerevisiae strains are genetically diverse, largely as a result of human efforts to develop strains specifically adapted to various fermentation processes. These adaptive pressures from various ecological niches have generated behavioral differences among these strains, particularly in terms of their nitrogen consumption capacities. In this work, we characterize this phenotype by the specific quantity of nitrogen consumed under oenological fermentation conditions using a new approach. Indeed, unlike previous studies, our experiments were conducted in an environment containing excess nitrogen, eliminating the nitrogen limitation/starvation factor that is generally observed in fermentation processes. Using these conditions, we evaluated differences in the nitrogen consumption capacities for a set of five strains from diverse origins. The strains presented extremely different phenotypes and variations in their capacities to take up nitrogen from a wine fermentation environment. These variations reflect the differences in the nitrogen uptake capacities between wine and non-wine strains. Finally, the strains differed in their ability to adapt to the nitrogen composition of the environment, leading to variations in the cellular stress states, fermentation performances and the activity of the nitrogen sensing signaling pathway. PMID:29432462

  1. Adaptability of the Saccharomyces cerevisiae yeasts to wine fermentation conditions relies on their strong ability to consume nitrogen.

    Science.gov (United States)

    Brice, Claire; Cubillos, Francisco A; Dequin, Sylvie; Camarasa, Carole; Martínez, Claudio

    2018-01-01

    Saccharomyces cerevisiae strains are genetically diverse, largely as a result of human efforts to develop strains specifically adapted to various fermentation processes. These adaptive pressures from various ecological niches have generated behavioral differences among these strains, particularly in terms of their nitrogen consumption capacities. In this work, we characterize this phenotype by the specific quantity of nitrogen consumed under oenological fermentation conditions using a new approach. Indeed, unlike previous studies, our experiments were conducted in an environment containing excess nitrogen, eliminating the nitrogen limitation/starvation factor that is generally observed in fermentation processes. Using these conditions, we evaluated differences in the nitrogen consumption capacities for a set of five strains from diverse origins. The strains presented extremely different phenotypes and variations in their capacities to take up nitrogen from a wine fermentation environment. These variations reflect the differences in the nitrogen uptake capacities between wine and non-wine strains. Finally, the strains differed in their ability to adapt to the nitrogen composition of the environment, leading to variations in the cellular stress states, fermentation performances and the activity of the nitrogen sensing signaling pathway.

  2. Moulds in food spoilage

    DEFF Research Database (Denmark)

    Filtenborg, Ole; Frisvad, Jens Christian; Thrane, Ulf

    1996-01-01

    There is an increasing knowledge and understanding of the role played by moulds in food spoilage. Especially the discovery of mycotoxin production in foods has highligh-ted the importance of moulds in food quality. It is, however, only within the last 5-10 years that major progresses have been made...... the associated or critical funga and has been shown to consist of less than 10 species. In this paper the associated funga is described for the following foods: Citrus and pomaceous fruits, potato and yam tubers, onions, rye, wheat, rye bread, cheese and fermented sausages and whenever possible the selective...

  3. Microbial Contribution to Wine Aroma and Its Intended Use for Wine Quality Improvement

    OpenAIRE

    Belda Aguilar, Ignacio; Ruiz, Javier; Esteban Fernández, Adelaida; Navascués, Eva; Marquina Díaz, Domingo; Santos de la Sen, Antonio; Moreno Arribas, M. Victoria

    2017-01-01

    Wine is a complex matrix that includes components with different chemical natures, the volatile compounds being responsible for wine aroma quality. The microbial ecosystem of grapes and wine, including Saccharomyces and non-Saccharomyces yeasts, as well as lactic acid bacteria, is considered by winemakers and oenologists as a decisive factor influencing wine aroma and consumer’s preferences. The challenges and opportunities emanating from the contribution of wine microbiome to the production ...

  4. De Novo Synthesis of Benzenoid Compounds by the Yeast Hanseniaspora vineae Increases the Flavor Diversity of Wines.

    Science.gov (United States)

    Martin, Valentina; Giorello, Facundo; Fariña, Laura; Minteguiaga, Manuel; Salzman, Valentina; Boido, Eduardo; Aguilar, Pablo S; Gaggero, Carina; Dellacassa, Eduardo; Mas, Albert; Carrau, Francisco

    2016-06-08

    Benzyl alcohol and other benzenoid-derived metabolites of particular importance in plants confer floral and fruity flavors to wines. Among the volatile aroma components in Vitis vinifera grape varieties, benzyl alcohol is present in its free and glycosylated forms. These compounds are considered to originate from grapes only and not from fermentative processes. We have found increased levels of benzyl alcohol in red Tannat wine compared to that in grape juice, suggesting de novo formation of this metabolite during vinification. In this work, we show that benzyl alcohol, benzaldehyde, p-hydroxybenzaldehyde, and p-hydroxybenzyl alcohol are synthesized de novo in the absence of grape-derived precursors by Hanseniaspora vineae. Levels of benzyl alcohol produced by 11 different H. vineae strains were 20-200 times higher than those measured in fermentations with Saccharomyces cerevisiae strains. These results show that H. vineae contributes to flavor diversity by increasing grape variety aroma concentration in a chemically defined medium. Feeding experiments with phenylalanine, tryptophan, tyrosine, p-aminobenzoic acid, and ammonium in an artificial medium were tested to evaluate the effect of these compounds either as precursors or as potential pathway regulators for the formation of benzenoid-derived aromas. Genomic analysis shows that the phenylalanine ammonia-lyase (PAL) and tyrosine ammonia lyase (TAL) pathways, used by plants to generate benzyl alcohols from aromatic amino acids, are absent in the H. vineae genome. Consequently, alternative pathways derived from chorismate with mandelate as an intermediate are discussed.

  5. Microbial Glycosidases for Wine Production

    Directory of Open Access Journals (Sweden)

    Sergi Maicas

    2016-08-01

    Full Text Available Winemaking is a complex process involving the interaction of different microbes. The two main groups of microorganisms involved are yeasts and bacteria. The yeasts present in spontaneous fermentation may be divided into two groups: the Saccharomyces yeasts, particularly S. cerevisiae; and the non-Saccharomyces yeasts, which include members of the genera Rhodotorula, Pichia, Candida, Debaryomyces, Metschtnikowia, Hansenula, and Hanseniaspora. S. cerevisiae yeasts are able to convert sugar into ethanol and CO2 via fermentation. They have been used by humans for thousands of years for the production of fermented beverages and foods, including wine. Their enzymes provide interesting organoleptic characteristics in wine. Glycosidases with oenological implications have been widely reported in yeasts, bacteria, and fungi. β-Glucosidase activity is involved in the release of terpenes to wine, thus contributing to varietal aroma. α-Rhamnosidase, α-arabinosidase, or β-apiosidase activities have also been reported to contribute to the wine production process. Oenococcus oeni (a lactic acid bacteria present in wine also has numerous glycosidases, and their activities contribute to the liberation of several aromatic compounds which contribute to floral and fruity wine characteristics.

  6. Microbiological Spoilage of Cereal Products

    Science.gov (United States)

    Cook, Frederick K.; Johnson, Billie L.

    A wide range of cereal products, including bakery items, refrigerated dough, fresh pasta products, dried cereal products, snack foods, and bakery mixes, are manufactured for food consumption. These products are subject to physical, chemical, and microbiological spoilage that affects the taste, aroma, leavening, appearance, and overall quality of the end consumer product. Microorganisms are ubiquitous in nature and have the potential for causing food spoilage and foodborne disease. However, compared to other categories of food products, bakery products rarely cause food poisoning. The heat that is applied during baking or frying usually eliminates pathogenic and spoilage microorganisms, and low moisture contributes to product stability. Nevertheless, microbiological spoilage of these products occurs, resulting in substantial economic losses.

  7. Wine yeast phenomics: A standardized fermentation method for assessing quantitative traits of Saccharomyces cerevisiae strains in enological conditions

    Science.gov (United States)

    Bernard, Margaux; Trujillo, Marine; Prodhomme, Duyên; Barbe, Jean-Christophe; Gibon, Yves; Marullo, Philippe

    2018-01-01

    This work describes the set up of a small scale fermentation methodology for measuring quantitative traits of hundreds of samples in an enological context. By using standardized screw cap vessels, the alcoholic fermentation kinetics of Saccharomyces cerevisiae strains were measured by following their weight loss over the time. This dispositive was coupled with robotized enzymatic assays for measuring metabolites of enological interest in natural grape juices. Despite the small volume used, kinetic parameters and fermentation end products measured are similar with those observed in larger scale vats. The vessel used also offers the possibility to assay 32 volatiles compounds using a headspace solid-phase micro-extraction coupled to gas chromatography and mass spectrometry. The vessel shaking applied strongly impacted most of the phenotypes investigated due to oxygen transfer occuring in the first hours of the alcoholic fermentation. The impact of grape must and micro-oxygenation was investigated illustrating some relevant genetic x environmental interactions. By phenotyping a wide panel of commercial wine starters in five grape juices, broad phenotypic correlations between kinetics and metabolic end products were evidentiated. Moreover, a multivariate analysis illustrates that some grape musts are more able than others to discriminate commercial strains since some are less robust to environmental changes. PMID:29351285

  8. Wine yeast phenomics: A standardized fermentation method for assessing quantitative traits of Saccharomyces cerevisiae strains in enological conditions.

    Science.gov (United States)

    Peltier, Emilien; Bernard, Margaux; Trujillo, Marine; Prodhomme, Duyên; Barbe, Jean-Christophe; Gibon, Yves; Marullo, Philippe

    2018-01-01

    This work describes the set up of a small scale fermentation methodology for measuring quantitative traits of hundreds of samples in an enological context. By using standardized screw cap vessels, the alcoholic fermentation kinetics of Saccharomyces cerevisiae strains were measured by following their weight loss over the time. This dispositive was coupled with robotized enzymatic assays for measuring metabolites of enological interest in natural grape juices. Despite the small volume used, kinetic parameters and fermentation end products measured are similar with those observed in larger scale vats. The vessel used also offers the possibility to assay 32 volatiles compounds using a headspace solid-phase micro-extraction coupled to gas chromatography and mass spectrometry. The vessel shaking applied strongly impacted most of the phenotypes investigated due to oxygen transfer occuring in the first hours of the alcoholic fermentation. The impact of grape must and micro-oxygenation was investigated illustrating some relevant genetic x environmental interactions. By phenotyping a wide panel of commercial wine starters in five grape juices, broad phenotypic correlations between kinetics and metabolic end products were evidentiated. Moreover, a multivariate analysis illustrates that some grape musts are more able than others to discriminate commercial strains since some are less robust to environmental changes.

  9. Identification of beer spoilage microorganisms using the MALDI Biotyper platform.

    Science.gov (United States)

    Turvey, Michelle Elizabeth; Weiland, Florian; Meneses, Jon; Sterenberg, Nick; Hoffmann, Peter

    2016-03-01

    Beer spoilage microorganisms present a major risk for the brewing industry and can lead to cost-intensive recall of contaminated products and damage to brand reputation. The applicability of molecular profiling using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in combination with Biotyper software was investigated for the identification of beer spoilage microorganisms from routine brewery quality control samples. Reference mass spectrum profiles for three of the most common bacterial beer spoilage microorganisms (Lactobacillus lindneri, Lactobacillus brevis and Pediococcus damnosus), four commercially available brewing yeast strains (top- and bottom-fermenting) and Dekkera/Brettanomyces bruxellensis wild yeast were established, incorporated into the Biotyper reference library and validated by successful identification after inoculation into beer. Each bacterial species could be accurately identified and distinguished from one another and from over 5600 other microorganisms present in the Biotyper database. In addition, wild yeast contaminations were rapidly detected and distinguished from top- and bottom-fermenting brewing strains. The applicability and integration of mass spectrometry profiling using the Biotyper platform into existing brewery quality assurance practices within industry were assessed by analysing routine microbiology control samples from a local brewery, where contaminating microorganisms could be reliably identified. Brewery-isolated microorganisms not present in the Biotyper database were further analysed for identification using LC-MS/MS methods. This renders the Biotyper platform a promising candidate for biological quality control testing within the brewing industry as a more rapid, high-throughput and cost-effective technology that can be tailored for the detection of brewery-specific spoilage organisms from the local environment.

  10. Characterization and control of Mucor circinelloides spoilage in yogurt.

    Science.gov (United States)

    Snyder, Abigail B; Churey, John J; Worobo, Randy W

    2016-07-02

    Consumer confidence in the food industry is severely affected by large-scale spoilage incidents. However, relatively little research exists on spoilage potential of members of the fungal subphylum Mucormycotina (e.g. Mucor), which includes dimorphic spoilage organisms that can switch between a yeast-like and hyphal phase depending on environmental conditions. The presence of Mucor circinelloides in yogurt may not cause spoilage, but growth and subsequent changes in quality (e.g. container bloating) can cause spoilage if not controlled. The purpose of this study was to evaluate the effects on M. circinelloides of pasteurization regimen, natamycin concentrations, and storage temperature in yogurt production, as measured by fungal proliferation and carbon dioxide production. A strain of M. circinelloides isolated from commercially spoiled yogurt showed greater yogurt-spoilage potential than clinical isolates and other industrial strains. D-values and z-values were determined for the spoilage isolate in milk as an evaluation of the fungus' ability to survive pasteurization. Natamycin was added to yogurt at 0, 5, 10, 15, and 20ppm (μg/ml) to determine its ability to inhibit M. circinelloides over the course of month-long challenge studies at 4°C, 15°C, and 25°C. Survivors were recovered on acidified PDA and carbon dioxide levels were recorded. The D-values at 54°C, 56°C, and 58°C for hyphae/sporangiospores were (in min) 38.31±0.02, 10.17±0.28, and 1.94±0.53, respectively, which yielded a z-value of 3.09°C. The D-values at 51°C, 53°C, and 55°C for yeast-like cells were (in min) 14.25±0.12, 6.87±1.19, and 2.44±0.35, respectively, which yielded a z-value of 0.34°C. These results indicated that M. circinelloides would not survive fluid milk pasteurization if contamination occurred prior to thermal treatment. CO2 production was only observed when M. circinelloides was incubated under low-oxygen conditions, and occurred only at temperatures above 4

  11. Fungal Spoilage in Food Processing.

    Science.gov (United States)

    Snyder, Abigail B; Worobo, Randy W

    2018-06-01

    Food processing, packaging, and formulation strategies are often specifically designed to inhibit or control microbial growth to prevent spoilage. Some of the most restrictive strategies rely solely or on combinations of pH reduction, preservatives, water activity limitation, control of oxygen tension, thermal processing, and hermetic packaging. In concert, these strategies are used to inactivate potential spoilage microorganisms or inhibit their growth. However, for select microbes that can overcome these controls, the lack of competition from additional background microbiota helps facilitate their propagation.

  12. Fish spoilage bacteria - problems and solutions

    DEFF Research Database (Denmark)

    Gram, Lone; Dalgaard, Paw

    2002-01-01

    Microorganisms are the major cause of spoilage of most seafood products. However, only a few members of the microbial community, the specific spoilage organisms (SSOs), give rise to the offensive off-flavours associated with seafood spoilage. Combining microbial ecology, molecular techniques, ana...

  13. Potential benefits of the application of yeast starters in table olive processing.

    Science.gov (United States)

    Arroyo-López, Francisco N; Romero-Gil, Verónica; Bautista-Gallego, Joaquín; Rodríguez-Gómez, Francisco; Jiménez-Díaz, Rufino; García-García, Pedro; Querol, Amparo; Garrido-Fernández, Antonio

    2012-01-01

    Yeasts play an important role in the food and beverage industry, especially in products such as bread, wine, and beer, among many others. However, their use as a starter in table olive processing has not yet been studied in detail. The candidate yeast strains should be able to dominate fermentation, together with lactic acid bacteria, but should also provide a number of beneficial advantages. Technologically, yeasts should resist low pH and high salt concentrations, produce desirable aromas, improve lactic acid bacteria growth, and inhibit spoilage microorganisms. Nowadays, they are being considered as probiotic agents because many species are able to resist the passage through the gastrointestinal tract and show favorable effects on the host. In this way, yeasts may improve the health of consumers by means of the degradation of non-assimilated compounds (such as phytate complexes), a decrease in cholesterol levels, the production of vitamins and antioxidants, the inhibition of pathogens, an adhesion to intestinal cell line Caco-2, and the maintenance of epithelial barrier integrity. Many yeast species, usually found in table olive processing (Wickerhamomyces anomalus, Saccharomyces cerevisiae, Pichia membranifaciens, and Kluyveromyces lactis, among others), have exhibited some of these properties. Thus, the selection of the most appropriate strains to be used as starters in this fermented vegetable, alone or in combination with lactic acid bacteria, is a promising research line to develop in the near future.

  14. Potential benefits of the application of yeast starters in table olive processing

    Science.gov (United States)

    Arroyo-López, Francisco N.; Romero-Gil, Verónica; Bautista-Gallego, Joaquín; Rodríguez-Gómez, Francisco; Jiménez-Díaz, Rufino; García-García, Pedro; Querol, Amparo; Garrido-Fernández, Antonio

    2012-01-01

    Yeasts play an important role in the food and beverage industry, especially in products such as bread, wine, and beer, among many others. However, their use as a starter in table olive processing has not yet been studied in detail. The candidate yeast strains should be able to dominate fermentation, together with lactic acid bacteria, but should also provide a number of beneficial advantages. Technologically, yeasts should resist low pH and high salt concentrations, produce desirable aromas, improve lactic acid bacteria growth, and inhibit spoilage microorganisms. Nowadays, they are being considered as probiotic agents because many species are able to resist the passage through the gastrointestinal tract and show favorable effects on the host. In this way, yeasts may improve the health of consumers by means of the degradation of non-assimilated compounds (such as phytate complexes), a decrease in cholesterol levels, the production of vitamins and antioxidants, the inhibition of pathogens, an adhesion to intestinal cell line Caco-2, and the maintenance of epithelial barrier integrity. Many yeast species, usually found in table olive processing (Wickerhamomyces anomalus, Saccharomyces cerevisiae, Pichia membranifaciens, and Kluyveromyces lactis, among others), have exhibited some of these properties. Thus, the selection of the most appropriate strains to be used as starters in this fermented vegetable, alone or in combination with lactic acid bacteria, is a promising research line to develop in the near future.

  15. Potential benefits of the application of yeast starters in table olive processing

    Directory of Open Access Journals (Sweden)

    Francisco Noé eArroyo López

    2012-04-01

    Full Text Available Yeasts play an important role in the food and beverage industry, especially in products such as bread, wine, and beer, among many others. However, their use as a starter in table olive processing has not yet been studied in detail. The candidate yeast strains should be able to dominate fermentation, together with lactic acid bacteria, but should also provide a number of beneficial advantages. Technologically, yeasts should resist low pH and high salt concentrations, produce desirable aromas, improve lactic acid bacteria growth and inhibit spoilage microorganisms. Nowadays, they are being considered as probiotic agents because many species are able to resist the passage through the gastrointestinal tract and show favourable effects on the host. In this way, yeasts may improve the health of consumers by means of the degradation of non assimilated compounds (such as phytate complexes, a decrease in cholesterol levels, the production of vitamins and antioxidants, the inhibition of pathogens, an adhesion to intestinal cell line Caco-2 and the maintenance of epithelial barrier integrity. Many yeast species, usually found in table olive processing (Wicherhamomyces anomalus, Saccharomyces cerevisiae, Pichia membranifaciens, Kluyveromyces lactis, among others, have exhibited some of these properties. Thus, the selection of the most appropriate strains to be used as starters in this fermented vegetable, alone or in combination with lactic acid bacteria, is a promising research line to develop in the near future.

  16. Vacuolar morphology of Saccharomyces cerevisiae during the process of wine making and Japanese sake brewing.

    Science.gov (United States)

    Izawa, Shingo; Ikeda, Kayo; Miki, Takeo; Wakai, Yoshinori; Inoue, Yoshiharu

    2010-09-01

    Although ethanol and osmotic stress affect the vacuolar morphology of Saccharomyces cerevisiae, little information is available about changes in vacuolar morphology during the processes of wine making and Japanese sake (rice wine) brewing. Here, we elucidated changes in the morphology of yeast vacuoles using Zrc1p-GFP, a vacuolar membrane protein, so as to better understand yeast physiology during the brewing process. Wine yeast cells (OC-2 and EC1118) contained highly fragmented vacuoles in the sake mash (moromi) as well as in the grape must. Although sake yeast cells (Kyokai no. 9 and no. 10) also contained highly fragmented vacuoles during the wine-making process, they showed quite a distinct vacuolar morphology during sake brewing. Since the environment surrounding sake yeast cells in the sake mash did not differ much from that surrounding wine yeast cells, the difference in vacuolar morphology during sake brewing between wine yeast and sake yeast was likely caused by innate characters.

  17. Use of non-Saccharomyces yeasts and oenological tannin in red winemaking: Influence on colour, aroma and sensorial properties of young wines.

    Science.gov (United States)

    Chen, Kai; Escott, Carlos; Loira, Iris; Del Fresno, Juan Manuel; Morata, Antonio; Tesfaye, Wendu; Calderon, Fernando; Suárez-Lepe, Jose Antonio; Han, Shunyu; Benito, Santiago

    2018-02-01

    Today, many non-Saccharomyces strains have been verified can be positive for the development of wine anthocyanin and aroma in different fermentation scenarios. Moreover, oenological tannins are widely used in wine industry to improve the colour profile and aroma complexity. The aim of this work is to analyze the fermentation characters of non-Saccharomyces strains and investigate the effects of pre-fermentative addition of oenological tannins on the wine components as well as sensory properties. For this purpose, five selected non-Saccharomyces strains and grape seed tannin were used to carry out the different fermentation trials. As a result, the grape seed tannin were less likely to influence growth kinetics of non-Saccharomyces strains. Schizosaccharomyces pombe has been proved can be effective to reduce the malic acid content while increase the level of vinylphenolic pyranoanthocyanin, which is positive for wine colour stability. Pre-fermentative use of oenological tannin was verified could be beneficial for the wines fermented with non-Saccharomyces regarding the improvement of wine colour, anthocyanin composition and the complexity of volatile compounds. Nevertheless, sensory analysis showed that oenological tannin could be less effective to modify the aroma impression of non-Saccharomyces wines. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Microbiological Spoilage of Fruits and Vegetables

    Science.gov (United States)

    Barth, Margaret; Hankinson, Thomas R.; Zhuang, Hong; Breidt, Frederick

    Consumption of fruit and vegetable products has dramatically increased in the United States by more than 30% during the past few decades. It is also estimated that about 20% of all fruits and vegetables produced is lost each year due to spoilage. The focus of this chapter is to provide a general background on microbiological spoilage of fruit and vegetable products that are organized in three categories: fresh whole fruits and vegetables, fresh-cut fruits and vegetables, and fermented or acidified vegetable products. This chapter will address characteristics of spoilage microorganisms associated with each of these fruit and vegetable categories including spoilage mechanisms, spoilage defects, prevention and control of spoilage, and methods for detecting spoilage microorganisms.

  19. Wine producers’ perceptions of wine tourism

    OpenAIRE

    Sevil, Güven; Yüncü, Hilmi Rafet

    2010-01-01

    Wine tourism has generated tremendous interest over the last two decades from both, both, industrial and academic circles. Wine tourism is a hybrid activity that integrates wine and tourism industries. Many wine regions and wine producers promote their wine through visitations of wineries. Wine, wine region and wine producers are main elements of wine tourism product. A successful wine tourism experience depends on point of view of producers on visitation to wineries as well as quality of win...

  20. Wine fraud

    OpenAIRE

    Holmberg, Lars

    2010-01-01

    Lars HolmbergFaculty of Law, University of Copenhagen, Copenhagen, DenmarkAbstract: Wine fraud may take several forms, of which two are discussed here: consumption fraud aimed at the wine market in general, and collector fraud aimed at the very top of the wine market. Examples of wine fraud past and present are given, and a suggestion about the extent of contemporary consumer fraud in Europe is provided. Technological possibilities for future detection and prevention of both forms of wine fra...

  1. Evaluation of potential antagonistism in yeasts, seeking biocontrol of spoilage by Penicillium expansumAvaliação do potencial antagônico de leveduras, visando biocontrole de deterioração por Penicillium expansum

    Directory of Open Access Journals (Sweden)

    Kei-ichi Harada

    2011-12-01

    Full Text Available Considerable losses during apple fruit storage occur due to microbiological diseases, mainly caused by Penicillium expansum, which in addition to fruit pulp deterioration produces patulin, a mycotoxin with carcinogenic and teratogenic activity. Biological control of post-harvest disease by antagonist yeasts focused on killer toxins is an appreciable alternative to the chemical fungicides, due to the low possibility of toxic residues demonstrated during fermentative processes. Twenty out of 44 yeasts (16 isolated from fruits, 10 from corn silage and 18 from laboratory anthill, showed antagonism against spores of P. expansum. The assay in solid medium pointed the strongest nutrient competition antagonism by D. hansenii strain C1 (31 mm inhibition diameter, while D. hansenii strain C7 (15 mm showed higher antibiosis and parasitism pattern. In the following step the extracellular activity was tested performing the assay with culture supernatant in Yeast Medium agar, where C. guilliermondii P3 was more effective against conidia germination (inhibition rate of 58.15% while P. ohmeri showed better inhibition on micelial growth (66.17%. The antibiosis showed by both yeasts could suggest probable mechanism associated with killer phenomenon, once both strains were killer positive against sensitive reference strains (S. cerevisiae NCYC 1006 and P. kluyveri CAY-15. In order to enhance the production of antifungal substance, these yeasts were cultivated with P. expansum, but the difference between culture supernatant obtained from yeasts cultivated alone and with mould was not significant (P > 0.05. The results demonstrated that the yeasts application constitute a promising tool, enhancing the biological control of P. expansum in post-harvest diseases of apple fruit.As perdas consideráveis no armazenamento de maçãs decorrem principalmente de desordens microbiológicas, causadas por Penicillium expansum, que além de colonizar o fruto e causar dano

  2. Calcium isotopes in wine

    Science.gov (United States)

    Holmden, C. E.

    2011-12-01

    Merlot grapes was -1.94%, which is lower than any of the bottled wines measured, thus far, whether white or red. The wine made from this juice yielded -1.16%, which points to fermentation being the principal source of isotopic variability found in bottled wine. The working hypothesis is that light isotopes of Ca are preferentially stripped from the juice during maceration, fermentation, and lees contact, by ion exchange sites on solid organic-matter comprising the skins and yeast and/or by Ca-tartrate precipitation. High quality wines (especially reds) tend to involve longer contact times between juice and skins in order to increase the extraction of color and phenolic compounds (tannins) from the grape skins, a practice that might also result in greater losses of light isotopes of Ca from the juice, thus explaining the isotopic pattern in bottled wine.

  3. Wine fraud

    Directory of Open Access Journals (Sweden)

    Lars Holmberg

    2010-10-01

    Full Text Available Lars HolmbergFaculty of Law, University of Copenhagen, Copenhagen, DenmarkAbstract: Wine fraud may take several forms, of which two are discussed here: consumption fraud aimed at the wine market in general, and collector fraud aimed at the very top of the wine market. Examples of wine fraud past and present are given, and a suggestion about the extent of contemporary consumer fraud in Europe is provided. Technological possibilities for future detection and prevention of both forms of wine fraud are discussed.Keywords: adulteration, counterfeit, detection

  4. Australian wine consumers’ acceptance of and attitudes toward the use of additives in wine and food production

    Directory of Open Access Journals (Sweden)

    Saltman Y

    2015-11-01

    Full Text Available Yaelle Saltman, Trent E Johnson, Kerry L Wilkinson, Susan EP Bastian Department of Wine and Food, School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus, Adelaide, SA, Australia. Abstract: Additives are routinely used in food and wine production to enhance product quality and/or prevent spoilage. Compared with other industries, the wine industry is only permitted to use a limited number of additives. Whereas flavor additives are often used to intensify the aroma and flavor of foods and beverages, the addition of flavorings to wine contravenes the legal definition of wine. Given the current legislation, it is perhaps not surprising that the potential use of food additives in wine production has not been explored. This study therefore investigated Australian wine consumers' acceptance of and attitudes toward the use of additives in food and wine production. Consumers (n=1,031 were segmented based on their self-reported wine knowledge (ie, subjective knowledge. Using these ratings, low (n=271, medium (n=528, and high (n=232 knowledge segments were identified. Consumers considered natural flavorings and colors, and additives associated with health benefits (eg, vitamins, minerals, and omega 3 fatty acids, to be acceptable food additives, irrespective of their level of wine knowledge. In contrast, the use of winemaking additives, even commonly used and legally permitted additives such as tartaric acid, preservatives, oak chips, and tannins, were considered far less acceptable, particularly, by less knowledgeable consumers. Surprisingly, natural flavorings were considered more acceptable than currently used winemaking additives. Consumers were therefore asked to identify the flavors they would most prefer in white and red wines. Fruit flavors featured prominently in consumer responses, eg, lemon and apple for white wines and blackcurrant and raspberry for red wines, but vanilla and/or chocolate, ie, attributes typically

  5. The use of chitooligosaccharide in beer brewing for protection against beer-spoilage bacteria and its influence on beer performance.

    Science.gov (United States)

    Zhao, Xue; Yu, Zhimin; Wang, Ting; Guo, Xuan; Luan, Jing; Sun, Yumei; Li, Xianzhen

    2016-04-01

    To identify a biological preservative that can protect beer from microbial contamination, which often results in the production of turbidity and off-flavor. The antimicrobial activity of a chitooligosaccharide against beer-spoilage bacteria and its effect on the fermentation performance of brewer's yeast was studied. Chitooligosaccharide with an average 2 kDa molecular weight was the best at inhibiting all tested beer-spoilage bacteria. The application of chitooligosaccharide in the brewing process did not influence the fermentation of brewer's yeast. The change in beer performance induced by the contamination of Lactobacillus brevis could be effectively controlled by application of chitooligosaccharide in the beer brewing process. The experimental data suggested that chitooligosaccharide should be an excellent preservative to inhibit beer-spoilage bacteria in the brewing process and in the end product.

  6. Effect of increasing growth temperature on yeast fermentation ...

    African Journals Online (AJOL)

    The effect of increasing growth temperature on yeast fermentation was studied at approximately 5 oC intervals over a range of 18 – 37 oC, using one strain each of ale, lager and wine yeast. The ale and wine yeasts grew at all the temperatures tested, but lager yeast failed to grow at 37 oC. All these strains gave lower ...

  7. Wine phenolics.

    Science.gov (United States)

    Waterhouse, Andrew L

    2002-05-01

    Wine contains many phenolic substances, most of which originate in the grape berry. The phenolics have a number of important functions in wine, affecting the tastes of bitterness and astringency, especially in red wine. Second, the color of red wine is caused by phenolics. Third, the phenolics are the key wine preservative and the basis of long aging. Lastly, since phenolics oxidize readily, they are the component that suffers owing to oxidation and the substance that turns brown in wine (and other foods) when exposed to air. Wine phenolics include the non-flavonoids: hydroxycinnamates, hydroxybenzoates and the stilbenes; plus the flavonoids: flavan-3-ols, the flavonols, and the anthocyanins. While polymeric condensed tannins and pigmented tannins constitute the majority of wine phenolics, their large size precludes absorption and thus they are not likely to have many health effects (except, perhaps, in the gut). The total amount of phenols found in a glass of red wine is on the order of 200 mg versus about 40 mg in a glass of white wine.

  8. The Occurrence of Beer Spoilage Lactic Acid Bacteria in Craft Beer Production.

    Science.gov (United States)

    Garofalo, Cristiana; Osimani, Andrea; Milanović, Vesna; Taccari, Manuela; Aquilanti, Lucia; Clementi, Francesca

    2015-12-01

    Beer is one of the world's most ancient and widely consumed fermented alcoholic beverages produced with water, malted cereal grains (generally barley and wheat), hops, and yeast. Beer is considered an unfavorable substrate of growth for many microorganisms, however, there are a limited number of bacteria and yeasts, which are capable of growth and may spoil beer especially if it is not pasteurized or sterile-filtered as craft beer. The aim of this research study was to track beer spoilage lactic acid bacteria (LAB) inside a brewery and during the craft beer production process. To that end, indoor air and work surface samples, collected in the brewery under study, together with commercial active dry yeasts, exhausted yeasts, yeast pellet (obtained after mature beer centrifugation), and spoiled beers were analyzed through culture-dependent methods and PCR-DGGE in order to identify the contaminant LAB species and the source of contamination. Lactobacillus brevis was detected in a spoiled beer and in a commercial active dry yeast. Other LAB species and bacteria ascribed to Staphylococcus sp., Enterobaceriaceae, and Acetobacter sp. were found in the brewery. In conclusion, the PCR-DGGE technique coupled with the culture-dependent method was found to be a useful tool for identifying the beer spoilage bacteria and the source of contamination. The analyses carried out on raw materials, by-products, final products, and the brewery were useful for implementing a sanitization plan to be adopted in the production plant. © 2015 Institute of Food Technologists®

  9. Beer spoilage bacteria and hop resistance

    NARCIS (Netherlands)

    Sakamoto, K; Konings, WN

    2003-01-01

    For brewing industry, beer spoilage bacteria have been problematic for centuries. They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and

  10. Micro-oxygenation of red wine: techniques, applications, and outcomes.

    Science.gov (United States)

    Schmidtke, Leigh M; Clark, Andrew C; Scollary, Geoff R

    2011-02-01

    Wine micro-oxygenation (MOX) is the controlled addition of oxygen to wine in a manner designed to ensure that complete mass transfer of molecular oxygen from gaseous to dissolved state occurs. MOX was initially developed to improve the body, structure, and fruitfulness in red wines with high concentrations of tannins and anthocyanins, by replicating the ingress of oxygen thought to arise from barrel maturation, but without the need for putting all wine to barrel. This review describes the operational parameters essential for the effective performance of the micro-oxidation process as well as the chemical and microbiological outcomes. The methodologies for introducing oxygen into the wine, the rates of oxygen addition, and their relationship to oxygen solubility in the wine matrix are examined. The review focuses on the techniques used for monitoring the MOX process, including sensory assessment, physicochemical properties, and the critical balance of the rate of oxygen addition in relation to maintaining the sulfur dioxide concentration. The chemistry of oxygen reactivity with wine components, the changes in wine composition that occur as a consequence of MOX, and the potential for wine spoilage if proper monitoring is not adopted are examined. Gaps in existing knowledge are addressed focusing on the limitations associated with the transfer of concepts from research trials in small volume tanks to commercial practice, and the dearth of kinetic data for the various chemical and physical processes that are claimed to occur during MOX.

  11. Microbiological Spoilage of Canned Foods

    Science.gov (United States)

    Evancho, George M.; Tortorelli, Suzanne; Scott, Virginia N.

    Nicolas Appert (1749-1841) developed the first commercial process that kept foods from spoiling in response to an offer from the French government for a method of preserving food for use by the army and navy. Appert, a confectioner and chef, began to experiment in his workshop in Massy, near Paris, but since little was known about bacteriology and the causes of spoilage (Louis Pasteur had yet to formulate the germ theory), much of his work involved trial and error. In 1810, after years of experimenting, he was awarded the prize of 12,000 francs for his method of preservation, which involved cooking foods in sealed jars at high temperatures. He described his method of preserving food in a book published in 1811, "L'Art De Conserver, Pendant Plusiers Annes, Toutes les Substances Animales et Végétales," which translated means "The Art of Preserving All Kinds of Animal and Vegetable Substances for Several Years." He later built a bottling factory and began to produce preserved foods for the people of France and is credited with being the "Father of Canning."

  12. Bread, beer and wine: Saccharomyces cerevisiae diversity reflects human history.

    Science.gov (United States)

    Legras, Jean-Luc; Merdinoglu, Didier; Cornuet, Jean-Marie; Karst, Francis

    2007-05-01

    Fermented beverages and foods have played a significant role in most societies worldwide for millennia. To better understand how the yeast species Saccharomyces cerevisiae, the main fermenting agent, evolved along this historical and expansion process, we analysed the genetic diversity among 651 strains from 56 different geographical origins, worldwide. Their genotyping at 12 microsatellite loci revealed 575 distinct genotypes organized in subgroups of yeast types, i.e. bread, beer, wine, sake. Some of these groups presented unexpected relatedness: Bread strains displayed a combination of alleles intermediate between beer and wine strains, and strains used for rice wine and sake were most closely related to beer and bread strains. However, up to 28% of genetic diversity between these technological groups was associated with geographical differences which suggests local domestications. Focusing on wine yeasts, a group of Lebanese strains were basal in an F(ST) tree, suggesting a Mesopotamia-based origin of most wine strains. In Europe, migration of wine strains occurred through the Danube Valley, and around the Mediterranean Sea. An approximate Bayesian computation approach suggested a postglacial divergence (most probable period 10,000-12,000 bp). As our results suggest intimate association between man and wine yeast across centuries, we hypothesize that yeast followed man and vine migrations as a commensal member of grapevine flora.

  13. Acceleration of ageing on lees in red wines by application of ultrasounds

    OpenAIRE

    Fresno, Juan Manuel del; Morata Barrado, Antonio Dionisio; Loira, Iris; Escott, Carlos; Cuerda, Rafael; Calderon Fernandez, Fernando; Suarez Lepe, Jose Antonio

    2017-01-01

    A transfer of parietal polysaccharides and mannoproteins is produced during aging on lees [1]. This transfer of compounds to wine is carried out after cell death. It comes to breakdown of polysaccharides from cell wall (yeast autolysis). This technique increases the density in wines [2] and gives more body and structure. Interactions between yeast polysaccharides and wine tannins will result in decrease of tannic perception (decrease of astringency). Increase of varietal characteristics is pr...

  14. Undergraduate Laboratory Exercises Specific to Food Spoilage Microbiology

    Science.gov (United States)

    Snyder, Abigail B.; Worobo, Randy W.; Orta-Ramirez, Alicia

    2016-01-01

    Food spoilage has an enormous economic impact, and microbial food spoilage plays a significant role in food waste and loss; subsequently, an equally significant portion of undergraduate food microbiology instruction should be dedicated to spoilage microbiology. Here, we describe a set of undergraduate microbiology laboratory exercises that focus…

  15. Isolation and Identification of Spoilage Fungi Associated With Rice ...

    African Journals Online (AJOL)

    The spoilage fungi isolated were Aspergillus species, Rhizopus, Penicilluim, Fusarium, Eurotium, Mucor, Geotrichum, Alternaria, Cladosporium and Actinomyces species. The predominant spoilage fungi in the grains were Aspergillus species. The populations of some spoilage fungi isolated from the grains were not high ...

  16. Modeling growth of specific spoilage organisms in tilapia ...

    African Journals Online (AJOL)

    Tilapia is an important aquatic fish, but severe spoilage of tilapia is most likely related to the global aquaculture. The spoilage is mostly caused by specific spoilage organisms (SSO). Therefore, it is very important to use microbial models to predict the growth of SSO in tilapia. This study firstly verified Pseudomonas and Vibrio ...

  17. Genetics of Yeasts

    Science.gov (United States)

    Querol, Amparo; Fernández-Espinar, M. Teresa; Belloch, Carmela

    The use of yeasts in biotechnology processes dates back to ancient days. Before 7000 BC, beer was produced in Sumeria. Wine was made in Assyria in 3500 BC, and ancient Rome had over 250 bakeries, which were making leavened bread by 100 BC. And milk has been made into Kefyr and Koumiss in Asia for many centuries (Demain, Phaff, & Kurtzman, 1999). However, the importance of yeast in the food and beverage industries was only realized about 1860, when their role in food manufacturing became evident.

  18. Comparative Analysis of Total Phenolic Content in Sea Buckthorn Wine and Other Selected Fruit Wines

    OpenAIRE

    Bharti Negi; Gargi Dey

    2009-01-01

    This is the first report from India on a beverage resulting from alcoholic fermentation of the juice of sea buckthorn (Hippophae rhamnoides L) using lab isolated yeast strain. The health promoting potential of the product was evaluated based on its total phenolic content. The most important finding was that under the present fermentation condition, the total phenolic content of the wine product was 689 mg GAE/L. Investigation of influence of bottle ageing on the sea buckthorn wine showed a sl...

  19. Natural and modified promoters for tailored metabolic engineering of the yeast Saccharomyces cerevisiae

    NARCIS (Netherlands)

    Hubmann, Georg; Thevelein, Johan M; Nevoigt, Elke

    2014-01-01

    The ease of highly sophisticated genetic manipulations in the yeast Saccharomyces cerevisiae has initiated numerous initiatives towards development of metabolically engineered strains for novel applications beyond its traditional use in brewing, baking, and wine making. In fact, baker's yeast has

  20. Terroir of yeasts? – Application of FTIR spectroscopy and molecular methods for strain typing of yeasts

    Directory of Open Access Journals (Sweden)

    Gerhards Daniel

    2015-01-01

    Full Text Available The site specific influence on wine (Terroir is an often by wine producers, consumers and scientists discussed topic in the world of wine. A study on grapes and (spontaneous fermentations from six different vineyards was done to investigate the biodiversity of yeasts and to answer the question if there is a terroir of yeast and how it could be influenced. Randomly isolated yeasts were identified by FTIR-spectroscopy and molecular methods on species and strain level. Vineyard specific yeast floras would be observed but they are not such important as expected. Only a few overlapping strain patterns would be identified during both vintages. The yeast flora of the winery had a huge impact on the spontaneous fermentations, but is not really constant and influenced by different factors from outside.

  1. WINE AND WINE TOURISM IN MACEDONIA

    Directory of Open Access Journals (Sweden)

    Cane Koteski

    2016-07-01

    Full Text Available Wine (Latin: vinum is an alcoholic beverage obtained by the fermentation of the grapes, the fruit of the vine plant. In Europe, according to legal regulations, the wine is the product obtained exclusively by full or partial fermentation of fresh grapes, clove or not, or of grape must. The transformation of grapes into wine is called vinification. The science of wine is called oenology. In some other parts of the world, the word wine can be true of alcohol obtained from other types of fruit. These wines are referred to as fruit wines, or wear a name by which the fruit is used for obtaining them (for example apple wine. Wine tourism is a type of tourism that involves visiting wineries, tasting, consumption and purchase of wine, usually directly from the manufacturer. This type of tourism includes visits to wineries, vineyards and restaurants famous for special local wines, as well as organized wine tours, visits to wine festivals and other special events. Many wine regions around the world to promote this tourism because it affects very positively to the local economy. In these regions, viticulture and hospitality organizations have spent significant resources over the years for the promotion of wine tourism. Wine tourism in my country is respected, but strong growth.

  2. 无核白甜葡萄酒产香酵母菌种筛选及其发酵性能研究%Screening of A Yeast Strain with Aroma-producing Capability for Seedless White Grape Wine & Study of Its Fermenting Performance

    Institute of Scientific and Technical Information of China (English)

    雷静; 吴斌; 郭峰; 韩琛; 陈雅; 阿依加马丽

    2016-01-01

    Wine aroma is an important sensory index in the evaluation of wine quality. Aromatic substances are also the important components of both grape and grape wine. Seedless white grape belongs to white grape and its intrinsic aroma is weak. Accordingly, the use of yeast strains with good aroma-producing capabilities in wine-making by seedless white grape is a reliable and safe approach. In the experiments, a yeast strain with good aroma-producing capabilities named W4 was isolated from naturally fermented liquid of seedless white grape. Meanwhile, the fermenting performance of W4 was investigated and the optimum technical parameters were summed up as follows:pH value=3, fermenting temperature at 20℃, and the initial sugar content was 230 g/L. The total esters content in the produced wine by W4 reached up to 7.335 g/L. The screened W4 could increase total esters content in grape wine effectively and evidently.%葡萄酒的香气是评判葡萄酒品质一个重要的感官指标,芳香物质也是构成葡萄和葡萄酒的重要成分。无核白葡萄属于白皮葡萄,自身带有的果香味淡薄。这就需要在酿造工艺上加以改进,采用产香酿酒酵母是可靠安全的增香手段。本研究通过对无核白葡萄自然发酵液分离初筛,筛选出1株产香较好的酵母菌株,命名为W4。同时对筛选出的W4产香酵母菌种进行发酵性能参数确定。通过实验分析得出:W4菌株最适pH值为3、最适发酵温度为20℃、最适初始糖度为230 g/L,发酵所得葡萄酒产酯总量为7.335 g/L。筛选出的菌株可以有效、明显地提高葡萄酒的总酯含量。

  3. Changes in aromatic compounds of cabernet sauvignon wines ...

    African Journals Online (AJOL)

    Administrator

    2011-09-21

    Sep 21, 2011 ... headspace solid phase microextraction (HS-SPME) and gas chromatography mass ... profiles of all the aroma compounds for cabernet sauvignon wines were increasingly diverse. The ... fermented in 30 T stainless steel tanks with activated dry yeast ..... volatile organic acids during yeast fermentation is.

  4. WINE AND WINE TOURISM IN MACEDONIA

    OpenAIRE

    Cane Koteski; Zlatko Jakovlev; Dragana Soltirovska

    2016-01-01

    Wine (Latin: vinum) is an alcoholic beverage obtained by the fermentation of the grapes, the fruit of the vine plant. In Europe, according to legal regulations, the wine is the product obtained exclusively by full or partial fermentation of fresh grapes, clove or not, or of grape must. The transformation of grapes into wine is called vinification. The science of wine is called oenology. In some other parts of the world, the word wine can be true of alcohol obtained ...

  5. Changes in sparkling wine aroma during the second fermentation under CO2 pressure in sealed bottle.

    Science.gov (United States)

    Martínez-García, Rafael; García-Martínez, Teresa; Puig-Pujol, Anna; Mauricio, Juan Carlos; Moreno, Juan

    2017-12-15

    High quality sparkling wine made by the traditional method requires a second alcoholic fermentation of a base wine in sealed bottles, followed by an aging time in contact with yeast lees. The CO 2 overpressure released during this second fermentation has an important effect on the yeast metabolism and therefore on the wine aroma composition. This study focuses on the changes in chemical composition and 43 aroma compounds released by yeast during this fermentation carried out under two pressure conditions. The data were subjected to statistical analysis allowing differentiating between the base wine and the wine samples taken in the middle and at the end of fermentation. The differentiation among wines obtained to the end of fermentation with or without CO 2 pressure is only achieved by a principal component analysis of 15 selected minor compounds (mainly ethyl dodecanoate, ethyl tetradecanoate, hexyl acetate, ethyl butanoate and ethyl isobutanoate). Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Talking About Wine

    Science.gov (United States)

    Lehrer, Adrienne

    1975-01-01

    A structural analysis of the wine vocabulary used by wine experts is given. Experiments involving typical wine drinkers show that there is little consensus in how the words are applied to wine. Communication tasks show that the sender and receiver of messages about wine perform little better than chance. (Author/RM)

  7. Wine and heart health

    Science.gov (United States)

    Health and wine; Wine and heart disease; Preventing heart disease - wine; Preventing heart disease - alcohol ... more often just to lower your risk of heart disease. Heavier drinking can harm the heart and ...

  8. Bacterial spoilage profiles to identify irradiated fish

    International Nuclear Information System (INIS)

    Alur, M.D.; Venugopal, V.; Nerkar, D.P.; Nair, P.M.

    1991-01-01

    Effects of low dose gamma-irradiation of fish product on spoilage potentials of bacteria (Aeromonas hydrophila, Salmonella typhimurium, Bacillus megaterium, and Pseudomonas marinoglutinosa) and mixed flora were examined for ability to proliferate in radurized fish and produce volatile acids (TVA) and bases (TVBN). Bacteria proliferated well in unirradiated and irradiated fish, but formation of VA and VB were lower in irradiated than unirradiated counterparts. This was found in Bombay duck, Indian mackerel, white pomfret, seer and shrimp gamma-irradiated at 0 to 5 kGy under ice. TVA and TVBN produced by the organisms or mixed flora from fish were only 30-50% those of controls. A method for identifying radiation-processed fish could evolve based on lower susceptibility of irradiated fish to bacterial spoilage

  9. Production of Food Grade Yeasts

    Directory of Open Access Journals (Sweden)

    Argyro Bekatorou

    2006-01-01

    Full Text Available Yeasts have been known to humans for thousands of years as they have been used in traditional fermentation processes like wine, beer and bread making. Today, yeasts are also used as alternative sources of high nutritional value proteins, enzymes and vitamins, and have numerous applications in the health food industry as food additives, conditioners and flavouring agents, for the production of microbiology media and extracts, as well as livestock feeds. Modern scientific advances allow the isolation, construction and industrial production of new yeast strains to satisfy the specific demands of the food industry. Types of commercial food grade yeasts, industrial production processes and raw materials are highlighted. Aspects of yeast metabolism, with respect to carbohydrate utilization, nutritional aspects and recent research advances are also discussed.

  10. Beer spoilage bacteria and hop resistance.

    Science.gov (United States)

    Sakamoto, Kanta; Konings, Wil N

    2003-12-31

    For brewing industry, beer spoilage bacteria have been problematic for centuries. They include some lactic acid bacteria such as Lactobacillus brevis, Lactobacillus lindneri and Pediococcus damnosus, and some Gram-negative bacteria such as Pectinatus cerevisiiphilus, Pectinatus frisingensis and Megasphaera cerevisiae. They can spoil beer by turbidity, acidity and the production of unfavorable smell such as diacetyl or hydrogen sulfide. For the microbiological control, many advanced biotechnological techniques such as immunoassay and polymerase chain reaction (PCR) have been applied in place of the conventional and time-consuming method of incubation on culture media. Subsequently, a method is needed to determine whether the detected bacterium is capable of growing in beer or not. In lactic acid bacteria, hop resistance is crucial for their ability to grow in beer. Hop compounds, mainly iso-alpha-acids in beer, have antibacterial activity against Gram-positive bacteria. They act as ionophores which dissipate the pH gradient across the cytoplasmic membrane and reduce the proton motive force (pmf). Consequently, the pmf-dependent nutrient uptake is hampered, resulting in cell death. The hop-resistance mechanisms in lactic acid bacteria have been investigated. HorA was found to excrete hop compounds in an ATP-dependent manner from the cell membrane to outer medium. Additionally, increased proton pumping by the membrane bound H(+)-ATPase contributes to hop resistance. To energize such ATP-dependent transporters hop-resistant cells contain larger ATP pools than hop-sensitive cells. Furthermore, a pmf-dependent hop transporter was recently presented. Understanding the hop-resistance mechanisms has enabled the development of rapid methods to discriminate beer spoilage strains from nonspoilers. The horA-PCR method has been applied for bacterial control in breweries. Also, a discrimination method was developed based on ATP pool measurement in lactobacillus cells. However

  11. Divergence in wine characteristics produced by wild and domesticated strains of Saccharomyces cerevisiae

    Science.gov (United States)

    Hyma, Katie E; Saerens, Sofie M; Verstrepen, Kevin J; Fay, Justin C

    2011-01-01

    The budding yeast Saccharomyces cerevisiae is the primary species used by wine makers to convert sugar into alcohol during wine fermentation. Saccharomyces cerevisiae is found in vineyards, but is also found in association with oak trees and other natural sources. Although wild strains of S. cerevisiae as well as other Saccharomyces species are also capable of wine fermentation, a genetically distinct group of S. cerevisiae strains is primarily used to produce wine, consistent with the idea that wine making strains have been domesticated for wine production. In this study, we demonstrate that humans can distinguish between wines produced using wine strains and wild strains of S. cerevisiae as well as its sibling species, Saccharomyces paradoxus. Wine strains produced wine with fruity and floral characteristics, whereas wild strains produced wine with earthy and sulfurous characteristics. The differences that we observe between wine and wild strains provides further evidence that wine strains have evolved phenotypes that are distinct from their wild ancestors and relevant to their use in wine production. PMID:22093681

  12. Genetic analysis of Saccharomyces cerevisiae strains isolated from palm wine in eastern Nigeria. Comparison with other African strains.

    Science.gov (United States)

    Ezeronye, O U; Legras, J-L

    2009-05-01

    To study the yeast diversity of Nigerian palm wines by comparison with other African strains. Twenty-three Saccharomyces cerevisiae strains were obtained from palm wine samples collected at four locations in eastern Nigeria, and characterized using different molecular techniques: internal transcribed spacer restriction fragment length polymorphism and sequence analysis, pulsed field gel electrophoresis, inter delta typing and microsatellite multilocus analysis. These techniques revealed that palm wine yeasts represent a group of closely related strains that includes other West African isolates (CBS400, NCYC110, DVPG6044). Population analysis revealed an excess of homozygote strains and an allelic richness similar to wine suggestive of local domestication. Several other African yeast strains were not connected to this group. Ghana sorghum beer strains and other African strains (DBVPG1853 and MUCL28071) displayed strikingly high relatedness with European bread, beer or wine strains, and the genome of strain MUCL30909 contained African and wine-type alleles, indicating its hybrid origin. Nigerian palm wine yeast represents a local specific yeast flora, whereas a European origin or hybrid was suspected for several other Africa isolates. This study presents the first genetic characterization of an autochthonous African palm wine yeast population and confirms the idea that human intervention has favoured yeast migration.

  13. Tears of Wine

    Science.gov (United States)

    Gugliotti, Marcos

    2004-01-01

    The unique occurrence of the upward motion of a thin film of wine, and its formation into drops inside the wall of a wine glass is explained. Evaporation of alcohol generates a surface tension gradient, moving the film of wine upwards on the internal sides of a wine glass, where it collects and forms into drops or tears.

  14. Port-Wine Stains

    Science.gov (United States)

    ... Safe Videos for Educators Search English Español Port-Wine Stains KidsHealth / For Parents / Port-Wine Stains What's ... Manchas de vino de oporto What Are Port-Wine Stains? A port-wine stain is a type ...

  15. Microbial diversity and biochemical characteristics of Borassus akeassii wine.

    Science.gov (United States)

    Tapsoba, F; Savadogo, A; Legras, J-L; Zongo, C; Traore, A S

    2016-10-01

    Palm wine produced traditionally and consumed by many people in the South-West of Burkina Faso is subject to alteration. In this study, we carried out a follow-up of two palm wines' fermentation during the 10 days in which palm wines are classically produced and consumed. We monitored biochemical characteristics of fermenting wines as well as followed the microflora kinetics using culture-dependent and culture-independent methods. The analysis of the acid content and the bacterial population revealed the correlation between the development of Lactic acid bacteria, acetic acid, and total acidity. Ribosomal intergenic spacer analysis and sequencing results revealed different yeast and bacterial populations for the two palm wines. Although Saccharomyces cerevisiae remained the sole yeast species in one fermentation, it was quickly replaced by Clavispora lusitaniae in the second fermentation, which had never been described until now in palm wine. When considering bacteria, the species Corynebacterium sp., Lactobacillus casei, Lactobacillus paracasei and Leuconostoc sp. were detected in both palm wines. But we also detected Acetobacter pasteurianus, Bacillus cereus and Bacillus thuringiensis in the second fermentation. Our results highlight the evolution of palm wine during the 10 days separating palm tapping and consumption of the fermented wine. The fermentation step is performed within few hours and completed after 24 h. The next days, its acidity increases progressively with the production of lactic and acetic acids by bacteria. The high production of acetic acid is very likely one of the main cause of palm wine degradation during this period. This indicates that the solution to palm wine preservation might be protection against oxygen, as well as the limit of bacterial growth through the use of preservatives. © 2016 The Society for Applied Microbiology.

  16. Between wine consumption and wine tourism: Consumer and spatial behavior of Israeli wine tourists

    OpenAIRE

    Shor, Noa; Mansfeld, Yoel

    2010-01-01

    The development of wine tourism worldwide has been accompanied by academic research on wine tourism and wine tourists. Wine tourists and wine enthusiasts have been found to share many socio-demographic similarities. It has been found that people visiting wineries consume wine on a regular basis, have an average to high level of knowledge about wine, and visit wineries and wine-producing regions a few times a year. Their involvement with wine is apparent both from their daily consumption and f...

  17. Brewing characteristics of piezosensitive sake yeasts

    Science.gov (United States)

    Nomura, Kazuki; Hoshino, Hirofumi; Igoshi, Kazuaki; Onozuka, Haruka; Tanaka, Erika; Hayashi, Mayumi; Yamazaki, Harutake; Takaku, Hiroaki; Iguchi, Akinori; Shigematsu, Toru

    2018-04-01

    Application of high hydrostatic pressure (HHP) treatment to food processing is expected as a non-thermal fermentation regulation technology that supresses over fermentation. However, the yeast Saccharomyces cerevisiae used for Japanese rice wine (sake) brewing shows high tolerance to HHP. Therefore, we aimed to generate pressure-sensitive (piezosensitive) sake yeast strains by mating sake with piezosensitive yeast strains to establish an HHP fermentation regulation technology and extend the shelf life of fermented foods. The results of phenotypic analyses showed that the generated yeast strains were piezosensitive and exhibited similar fermentation ability compared with the original sake yeast strain. In addition, primary properties of sake brewed using these strains, such as ethanol concentration, sake meter value and sake flavor compounds, were almost equivalent to those obtained using the sake yeast strain. These results suggest that the piezosensitive strains exhibit brewing characteristics essentially equivalent to those of the sake yeast strain.

  18. Effect of production phase on bottle-fermented sparkling wine quality.

    Science.gov (United States)

    Kemp, Belinda; Alexandre, Hervé; Robillard, Bertrand; Marchal, Richard

    2015-01-14

    This review analyzes bottle-fermented sparkling wine research at each stage of production by evaluating existing knowledge to identify areas that require future investigation. With the growing importance of enological investigation being focused on the needs of the wine production industry, this review examines current research at each stage of bottle-fermented sparkling wine production. Production phases analyzed in this review include pressing, juice adjustments, malolactic fermentation (MLF), stabilization, clarification, tirage, lees aging, disgorging, and dosage. The aim of this review is to identify enological factors that affect bottle-fermented sparkling wine quality, predominantly aroma, flavor, and foaming quality. Future research topics identified include regional specific varieties, plant-based products from vines, grapes, and yeast that can be used in sparkling wine production, gushing at disgorging, and methods to increase the rate of yeast autolysis. An internationally accepted sensory analysis method specifically designed for sparkling wine is required.

  19. Susceptibility of Pediococcus isolates to antimicrobial compounds in relation to hop-resistance and beer-spoilage

    Directory of Open Access Journals (Sweden)

    Ziola Barry

    2009-09-01

    Full Text Available Abstract Background Though important in the context of food microbiology and as potential pathogens in immuno-compromised humans, bacterial isolates belonging to the genus Pediococcus are best known for their association with contamination of ethanol fermentation processes (beer, wine, or fuel ethanol. Use of antimicrobial compounds (e.g., hop-compounds, Penicillin by some industries to combat Pediococcus contaminants is long-standing, yet knowledge about the resistance of pediococci to antimicrobial agents is minimal. Here we examined Pediococcus isolates to determine whether antibiotic resistance is associated with resistance to hops, presence of genes known to correlate with beer spoilage, or with ability to grow in beer. Results Lactic acid bacteria susceptibility test broth medium (LSM used in combination with commercially available GPN3F antimicrobial susceptibility plates was an effective method for assessing antimicrobial susceptibility of Pediococcus isolates. We report the finding of Vancomycin-susceptible Pediococcus isolates from four species. Interestingly, we found that hop-resistant, beer-spoilage, and beer-spoilage gene-harbouring isolates had a tendency to be more susceptible, rather than more resistant, to antimicrobial compounds. Conclusion Our findings indicate that the mechanisms involved in conferring hop-resistance or ability to spoil beer by Pediococcus isolates are not associated with resistance to antibiotics commonly used for treatment of human infections. Also, Vancomycin-resistance was found to be isolate-specific and not intrinsic to the genus as previously believed.

  20. Susceptibility of Pediococcus isolates to antimicrobial compounds in relation to hop-resistance and beer-spoilage.

    Science.gov (United States)

    Haakensen, Monique; Vickers, David M; Ziola, Barry

    2009-09-07

    Though important in the context of food microbiology and as potential pathogens in immuno-compromised humans, bacterial isolates belonging to the genus Pediococcus are best known for their association with contamination of ethanol fermentation processes (beer, wine, or fuel ethanol). Use of antimicrobial compounds (e.g., hop-compounds, Penicillin) by some industries to combat Pediococcus contaminants is long-standing, yet knowledge about the resistance of pediococci to antimicrobial agents is minimal. Here we examined Pediococcus isolates to determine whether antibiotic resistance is associated with resistance to hops, presence of genes known to correlate with beer spoilage, or with ability to grow in beer. Lactic acid bacteria susceptibility test broth medium (LSM) used in combination with commercially available GPN3F antimicrobial susceptibility plates was an effective method for assessing antimicrobial susceptibility of Pediococcus isolates. We report the finding of Vancomycin-susceptible Pediococcus isolates from four species. Interestingly, we found that hop-resistant, beer-spoilage, and beer-spoilage gene-harbouring isolates had a tendency to be more susceptible, rather than more resistant, to antimicrobial compounds. Our findings indicate that the mechanisms involved in conferring hop-resistance or ability to spoil beer by Pediococcus isolates are not associated with resistance to antibiotics commonly used for treatment of human infections. Also, Vancomycin-resistance was found to be isolate-specific and not intrinsic to the genus as previously believed.

  1. De novo production of six key grape aroma monoterpenes by a geraniol synthase-engineered S. cerevisiae wine strain.

    Science.gov (United States)

    Pardo, Ester; Rico, Juan; Gil, José Vicente; Orejas, Margarita

    2015-09-16

    Monoterpenes are important contributors to grape and wine aroma. Moreover, certain monoterpenes have been shown to display health benefits with antimicrobial, anti-inflammatory, anticancer or hypotensive properties amongst others. The aim of this study was to construct self-aromatizing wine yeasts to overproduce de novo these plant metabolites in wines. Expression of the Ocimum basilicum (sweet basil) geraniol synthase (GES) gene in a Saccharomyces cerevisiae wine strain substantially changed the terpene profile of wine produced from a non-aromatic grape variety. Under microvinification conditions, and without compromising other fermentative traits, the recombinant yeast excreted geraniol de novo at an amount (~750 μg/L) well exceeding (>10-fold) its threshold for olfactory perception and also exceeding the quantities present in wines obtained from highly aromatic Muscat grapes. Interestingly, geraniol was further metabolized by yeast enzymes to additional monoterpenes and esters: citronellol, linalool, nerol, citronellyl acetate and geranyl acetate, resulting in a total monoterpene concentration (~1,558 μg/L) 230-fold greater than that of the control. We also found that monoterpene profiles of wines derived from mixed fermentations were found to be determined by the composition of the initial yeast inocula suggesting the feasibility of producing 'à la carte' wines having predetermined monoterpene contents. Geraniol synthase-engineered yeasts demonstrate potential in the development of monoterpene enhanced wines.

  2. Mycology and spoilage of retail cashew nuts | Adebajo | African ...

    African Journals Online (AJOL)

    All the species recovered induced detectable loss in weights of the milled nuts, though to varying extents and would be expected to cause considerable spoilage of the nuts. Key words: Cashew nut, Anacardium occidentale, fungal count, mycology, Aspergillus sp., Penicillium sp., spoilage. African Journal of Biotechnology ...

  3. Effect of different storage temperatures on bacterial spoilage of ...

    African Journals Online (AJOL)

    This study determined the bacterial organisms associated with Oreochromis niloticus spoilage at two storage temperatures (6 and 20°C) and also assessed the ability of the individual bacterial isolates to cause spoilage at the two storage temperatures. Bacteriological analysis revealed the association of five bacteria ...

  4. Bacterial spoilage of fresh meat in some selected Lagos markets ...

    African Journals Online (AJOL)

    A study of the bacteria associated with spoilage of fresh meat was carried out. The flora causing spoilage of meat include Alcaligenes liquefaciens, Bacillus subtilis, Clostridium perfringes, Escherichia coli, Klebsiella pneumoniae, Lactobacillus sp., Micrococcus varians, Pseudomonas aeruginosa, Sarcina sp. Serratia ...

  5. Production and Quality Evaluation of Pineapple Fruit Wine

    Science.gov (United States)

    Qi, Ningli; Ma, Lina; Li, Liuji; Gong, Xiao; Ye, Jianzhi

    2017-12-01

    The fermentation process of pineapple fruit wine was studied. The juice was inoculated with 5% (v/v) active yeast and held at 20 °C for 7 days. Total sugar and pH decreased while the alcoholic strength increased with increasing length of fermentation. The fermented fruit wine contains 2.29 g/L total acid, 10.2 % (v/v) alcohol, 5.4 °Brix soluble solids, pH 3.52. Pineapple wine detected 68 kinds of aroma components, including 34 esters, 13 alcohols. The ester material accounted for 52.25% of the main aroma components. The quality and sensory evaluation results indicated that pineapple fruit wine belongs to a kind of low alcohol wine, so it is easy to be accepted by the public.

  6. Reduction in Acidity by Chemical and Microbiological Methods and Their Effect on Moslavac Wine Quality

    OpenAIRE

    Herjavec, Stanka; Majdak, Ana; Tupajić, Pavica; Redžepović, Sulejman; Orlić, Sandi

    2003-01-01

    Changes in chemical composition and sensory properties caused by chemical and microbiological methods of deacidification in Moslavac (syn. Furmint) wines were investigated. Alcoholic fermentation of Moslavac musts was carried out with two different strains of the yeasts Saccharomyces paradoxus. There were no marked differences in chemical composition among the wines. Compared to the control microbiological deacidification of wines by Oenococcus oeni resulted in a complete decomposition of mal...

  7. ORGANIC ACIDS CONCENTRATION IN WINE STOCKS AFTER Saccharomyces cerevisiae FERMENTATION

    Directory of Open Access Journals (Sweden)

    V. N. Bayraktar

    2013-04-01

    Full Text Available The biochemical constituents in wine stocks that influence the flavor and quality of wine are investigated in the paper. The tested parameters consist of volume fraction of ethanol, residual sugar, phenolic compounds, tartaric, malic, citric, lactic, acetic acids, titratable acidity and volatile acids. The wine stocks that were received from white and red grape varieties Tairov`s selection were tested. There was a correlation between titratable acidity and volatile acids in the wine stocks from white and red grape varieties. High correlation was also found between lactic and acetic acids, between volatile acids, acetic acid and sugar. It was determined that wine stocks with a high concentration of ethanol originated from those yeast strains of Saccharomyces cerevisiae, in a fermented grape must of high speed of enzyme activity. The taste of wine stocks correlated with the ratio of tartaric to malic acid. Analysis showed significant differences between the varieties of white and red wine stocks in concentrations of organic acids, phenolic compounds, residual sugar, and volume fraction of ethanol. Positive correlation was indicated for both studied groups for volatile acids and acetic acid, tartaric, malic, lactic acids and total sugar. Prospective yeast cultures with high productivity of alcohol (ethanol were selected for winemaking biotechnology.

  8. Relationships between harvest time and wine composition in Vitis vinifera L. cv. Cabernet Sauvignon 1. Grape and wine chemistry.

    Science.gov (United States)

    Bindon, Keren; Varela, Cristian; Kennedy, James; Holt, Helen; Herderich, Markus

    2013-06-01

    The study aimed to quantify the effects of grape maturity on wine alcohol, phenolics, flavour compounds and polysaccharides in Vitis vinifera L. cv Cabernet Sauvignon. Grapes were harvested at juice soluble solids from 20 to 26 °Brix which corresponded to a range of wine ethanol concentrations between 12% and 15.5%. Grape anthocyanin and skin tannin concentration increased as ripening progressed, while seed tannin declined. In the corresponding wines, monomeric anthocyanin and wine tannin concentration increased with harvest date, consistent with an enhanced extraction of skin-derived phenolics. In wines, there was an observed increase in yeast-derived metabolites, including volatile esters, dimethyl sulfide, glycerol and mannoproteins with harvest date. Wine volatiles which were significantly influenced by harvest date were isobutyl methoxypyrazine, C(6) alcohols and hexyl acetate, all of which decreased as ripening progressed. The implications of harvest date for wine composition is discussed in terms of both grape composition and yeast metabolism. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Measurement of labile copper in wine by medium exchange stripping potentiometry utilising screen printed carbon electrodes.

    Science.gov (United States)

    Clark, Andrew C; Kontoudakis, Nikolaos; Barril, Celia; Schmidtke, Leigh M; Scollary, Geoffrey R

    2016-07-01

    The presence of copper in wine is known to impact the reductive, oxidative and colloidal stability of wine, and techniques enabling measurement of different forms of copper in wine are of particular interest in understanding these spoilage processes. Electrochemical stripping techniques developed to date require significant pretreatment of wine, potentially disturbing the copper binding equilibria. A thin mercury film on a screen printed carbon electrode was utilised in a flow system for the direct analysis of labile copper in red and white wine by constant current stripping potentiometry with medium exchange. Under the optimised conditions, including an enrichment time of 500s and constant current of 1.0μA, the response range was linear from 0.015 to 0.200mg/L. The analysis of 52 red and white wines showed that this technique generally provided lower labile copper concentrations than reported for batch measurement by related techniques. Studies in a model system and in finished wines showed that the copper sulfide was not measured as labile copper, and that loss of hydrogen sulfide via volatilisation induced an increase in labile copper within the model wine system. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Globalization and wine business: Port wine

    OpenAIRE

    Rebelo, Joao; Correia, Leonida; Caldas, Jose Vaz

    2007-01-01

    In the past two decades the world has seen acceleration in the process of globalisation, affecting virtually all industries and consumers. The wine sector is no exception, witnessing increased exports and imports, decreasing consumption per capita in the producing countries, and a wave of direct foreign investment and mergers and acquisitions in the industry. Among European wine producers the Port wine can be seen as a representative case of globalisation and as a benchmark, because almost 90...

  11. Red wines good, white wines bad?

    International Nuclear Information System (INIS)

    Van Velden, D.P.; Mansvelt, E.P.G.; Troup, G.J.

    2002-01-01

    Full text: In 1994, free radicals were discovered in red wines, but only in whites exposed to skins and seeds, and/or oak. The radicals are on the phenolics, and therefore a measure of phenolic content. In 1995, Fuhrman, Levy and Aviram published a study showing antioxidant effects of red wine in the standard Israeli diet, but pro-oxidant effects of the white wine used. No phenolic analysis was done, but low or no phenolics were suspected. Letters to the winery used by Aviram proved fruitless. In 2001, Aviram admits that to see a significant antioxidant effect from white wine, he must make his own, giving it skin and seed contact, and adding alcohol to the fermenting stage, to leach out more tannin from the seeds. This would be unsaleable as a table wine, but not as a 'fortified' or 'dessert' wine. A completely independent study by van Velden in South Africa, with phenol analysis of wines, shows pro- oxidant behaviour of white wines low or lacking in phenolic content. This will be summarised. A Japanese study of the antioxidant properties of some wines shows none for wines low or lacking in catechin content. In the 1950's, two similar but independent studies on different laboratory animals showed no ill effects from 10% alcohol red wine in their diet, but serious effects from 10% pure alcohol - water mix. Conclusion. Drinking only of white wines lacking in phenols, either due to 'fining', or to deliberate avoidance in making, at the recommended 'moderate' drinking level, may be deleterious to cardiovascular health, because of their pro-oxidant action, now established

  12. Sensory profile and volatile aroma composition of reduced alcohol Merlot wines fermented with Metschnikowia pulcherrima and Saccharomyces uvarum.

    Science.gov (United States)

    Varela, C; Barker, A; Tran, T; Borneman, A; Curtin, C

    2017-07-03

    Strategies for production of wines containing lower alcohol concentrations are in strong demand, for reasons of quality, health, and taxation. Development and application of wine yeasts that are less efficient at transforming grape sugars into ethanol has the potential to allow winemakers the freedom to make lower alcohol wines from grapes harvested at optimal ripeness, without the need for post-fermentation processes aimed at removing ethanol. We have recently shown that two non-conventional wine yeast species Metschnikowia pulcherrima and Saccharomyces uvarum were both able to produce wine with reduced alcohol concentration. Both species produced laboratory-scale wines with markedly different volatile aroma compound composition relative to Saccharomyces cerevisiae. This work describes the volatile composition and sensory profiles of reduced-alcohol pilot-scale Merlot wines produced with M. pulcherrima and S. uvarum. Wines fermented with M. pulcherrima contained 1.0% v/v less ethanol than S. cerevisiae fermented wines, while those fermented with S. uvarum showed a 1.7% v/v reduction in ethanol. Compared to S. cerevisiae ferments, wines produced with M. pulcherrima showed higher concentrations of ethyl acetate, total esters, total higher alcohols and total sulfur compounds, while wines fermented with S. uvarum were characterised by the highest total concentration of higher alcohols. Sensorially, M. pulcherrima wines received relatively high scores for sensory descriptors such as red fruit and fruit flavour and overall exhibited a sensory profile similar to that of wine made with S. cerevisiae, whereas the main sensory descriptors associated with wines fermented with S. uvarum were barnyard and meat. This work demonstrates the successful application of M. pulcherrima AWRI3050 for the production of pilot-scale red wines with reduced alcohol concentration and highlights the need for rigorous evaluation of non-conventional yeasts with regard to their sensory impacts

  13. Yeasts Diversity in Fermented Foods and Beverages

    Science.gov (United States)

    Tamang, Jyoti Prakash; Fleet, Graham H.

    People across the world have learnt to culture and use the essential microorganisms for production of fermented foods and alcoholic beverages. A fermented food is produced either spontaneously or by adding mixed/pure starter culture(s). Yeasts are among the essential functional microorganisms encountered in many fermented foods, and are commercially used in production of baker's yeast, breads, wine, beer, cheese, etc. In Asia, moulds are predominant followed by amylolytic and alcohol-producing yeasts in the fermentation processes, whereas in Africa, Europe, Australia and America, fermented products are prepared exclusively using bacteria or bacteria-yeasts mixed cultures. This chapter would focus on the varieties of fermented foods and alcoholic beverages produced by yeasts, their microbiology and role in food fermentation, widely used commercial starters (pilot production, molecular aspects), production technology of some common commercial fermented foods and alcoholic beverages, toxicity and food safety using yeasts cultures and socio-economy

  14. Wine production in Denmark

    DEFF Research Database (Denmark)

    Bentzen, Jan Børsen; Smith, Valdemar

    By the end of the former century there were less than 10 commercial vintners producing wine in Denmark. There was widespread acceptance of the view that commercial production of wine in the most northern parts of Europe was impossible. However, the number of commercial wine growers in Denmark grew...... to more than 60 at the end of year 2009 and the Association of Danish Winegrowers now counts more than 1400 members. Denmark can no longer be seen as a non-wine producing country! Formally, the transformation of Denmark to a wine producing country took place in year 2000 when Denmark was accepted...... as a commercial wine producing nation within the European Union. Based on a remarkably detailed micro data set this paper first gives a description of wine production in Denmark and thereafter we address the question whether vineyard characteristics are important for the quality of the wine and/or whether...

  15. Interaction Between Yeasts and Zinc

    Science.gov (United States)

    Nicola, Raffaele De; Walker, Graeme

    Zinc is an essential trace element in biological systems. For example, it acts as a cellular membrane stabiliser, plays a critical role in gene expression and genome modification and activates nearly 300 enzymes, including alcohol dehydrogenase. The present chapter will be focused on the influence of zinc on cell physiology of industrial yeast strains of Saccharomyces cerevisiae, with special regard to the uptake and subsequent utilisation of this metal. Zinc uptake by yeast is metabolism-dependent, with most of the available zinc translocated very quickly into the vacuole. At cell division, zinc is distributed from mother to daughter cells and this effectively lowers the individual cellular zinc concentration, which may become zinc depleted at the onset of the fermentation. Zinc influences yeast fermentative performance and examples will be provided relating to brewing and wine fermentations. Industrial yeasts are subjected to several stresses that may impair fermentation performance. Such stresses may also impact on yeast cell zinc homeostasis. This chapter will discuss the practical implications for the correct management of zinc bioavailability for yeast-based biotechnologies aimed at improving yeast growth, viability, fermentation performance and resistance to environmental stresses

  16. Stuck fermentation: development of a synthetic stuck wine and study of a restart procedure.

    Science.gov (United States)

    Maisonnave, Pierre; Sanchez, Isabelle; Moine, Virginie; Dequin, Sylvie; Galeote, Virginie

    2013-05-15

    Stuck fermentation is a major problem in winemaking, resulting in large losses in the wine industry. Specific starter yeasts are used to restart stuck fermentations in conditions determined essentially on the basis of empirical know-how. We have developed a model synthetic stuck wine and an industrial process-based procedure for restarting fermentations, for studies of the conditions required to restart stuck fermentations. We used a basic medium containing 13.5% v/v ethanol and 16 g/L fructose, pH 3.3, to test the effect of various nutrients (vitamins, amino acids, minerals, oligoelements), with the aim of developing a representative and discriminative stuck fermentation model. Cell growth appeared to be a key factor for the efficient restarting of stuck fermentations. Micronutrients, such as vitamins, also strongly affected the efficiency of the restart procedure. For the validation of this medium, we compared the performances of three wine yeast strains in the synthetic stuck fermentation and three naturally stuck wine fermentations. Strain performance was ranked similar in the synthetic medium and in the "Malbec" and "Sauvignon" natural stuck wines. However, two strains were ranked differently in the "Gros Manseng" stuck wine. Nutrient content seemed to be a crucial factor in fermentation restart conditions, generating differences between yeast strains. However, the specific sensitivity of yeast strains to the composition of the wine may also have had an effect. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Genomic Evolution of Saccharomyces cerevisiae under Chinese Rice Wine Fermentation

    Science.gov (United States)

    Li, Yudong; Zhang, Weiping; Zheng, Daoqiong; Zhou, Zhan; Yu, Wenwen; Zhang, Lei; Feng, Lifang; Liang, Xinle; Guan, Wenjun; Zhou, Jingwen; Chen, Jian; Lin, Zhenguo

    2014-01-01

    Rice wine fermentation represents a unique environment for the evolution of the budding yeast, Saccharomyces cerevisiae. To understand how the selection pressure shaped the yeast genome and gene regulation, we determined the genome sequence and transcriptome of a S. cerevisiae strain YHJ7 isolated from Chinese rice wine (Huangjiu), a popular traditional alcoholic beverage in China. By comparing the genome of YHJ7 to the lab strain S288c, a Japanese sake strain K7, and a Chinese industrial bioethanol strain YJSH1, we identified many genomic sequence and structural variations in YHJ7, which are mainly located in subtelomeric regions, suggesting that these regions play an important role in genomic evolution between strains. In addition, our comparative transcriptome analysis between YHJ7 and S288c revealed a set of differentially expressed genes, including those involved in glucose transport (e.g., HXT2, HXT7) and oxidoredutase activity (e.g., AAD10, ADH7). Interestingly, many of these genomic and transcriptional variations are directly or indirectly associated with the adaptation of YHJ7 strain to its specific niches. Our molecular evolution analysis suggested that Japanese sake strains (K7/UC5) were derived from Chinese rice wine strains (YHJ7) at least approximately 2,300 years ago, providing the first molecular evidence elucidating the origin of Japanese sake strains. Our results depict interesting insights regarding the evolution of yeast during rice wine fermentation, and provided a valuable resource for genetic engineering to improve industrial wine-making strains. PMID:25212861

  18. Chemical, physical-chemical, and sensory characteristics of lychee (Litchi chinensis Sonn) wines.

    Science.gov (United States)

    Alves, Juliana Alvarenga; de Oliveira Lima, Luiz Carlos; Nunes, Cleiton Antônio; Dias, Disney Ribeiro; Schwan, Rosane Freitas

    2011-01-01

    Four lychee (Litchi chinensis Sonn) wines (prepared with 3 yeast strains [UFLA CA11, UFLA CA1183, and UFLA CA1174]) and a spontaneous fermentation (SPON) were done in order to add value to the fruit while preventing waste arising from the short shelf life of lychee. The fermentation was monitored daily by analyzing the soluble solids, pH, acidity, ethanol, and sugar. At the end of fermentation, the wines were subjected to chemical, physical-chemical, and sensory analysis. The wines prepared showed greater variations in the qualitative than in the quantitative analysis of their constituents. The sensory analysis indicated that the wines fermented by yeast UFLA CA1183 and UFLA CA11 had rates of acceptance above 75%. The principal components analysis separated the wines into 2 groups according to the analyzed compounds. Based on these analyses, the wine produced by inoculation with UFLA CA1183 proved to be the most suitable for the production of lychee wines. Development of new products and adding value to fruits. Importance of selection of specific yeasts for production of fruit wine. © 2011 Institute of Food Technologists®

  19. Yeast cell factories on the horizon

    DEFF Research Database (Denmark)

    Nielsen, Jens

    2015-01-01

    For thousands of years, yeast has been used for making beer, bread, and wine. In modern times, it has become a commercial workhorse for producing fuels, chemicals, and pharmaceuticals such as insulin, human serum albumin, and vaccines against hepatitis virus and human papillomavirus. Yeast has also...... been engineered to make chemicals at industrial scale (e.g., succinic acid, lactic acid, resveratrol) and advanced biofuels (e.g., isobutanol) (1). On page 1095 of this issue, Galanie et al. (2) demonstrate that yeast can now be engineered to produce opioids (2), a major class of compounds used...

  20. Torulaspora delbrueckii for secondary fermentation in sparkling wine production.

    Science.gov (United States)

    Canonico, Laura; Comitini, Francesca; Ciani, Maurizio

    2018-09-01

    In the search for the desired oenological features and flavour complexity of wines, there is growing interest in the potential use of non-Saccharomyces yeast that are naturally present in the winemaking environment. Torulaspora delbrueckii is one such yeast that has seen profitable use in mixed fermentations with Saccharomyces cerevisiae and with different grape varieties. T. delbrueckii can have positive and distinctive impacts on the overall aroma of wines, and has also been used at an industrial level. Here, T. delbrueckii was successfully used in pure and mixed secondary fermentations for sparkling wine. The two selected T. delbrueckii strains used completed the secondary fermentation 'prise de mousse' in these pure and mixed fermentations. The sparkling wines obtained with T. delbrueckii showed different aromatic compositions and sensory profiles to those of S. cerevisiae. T. delbrueckii strain DiSVA 130 showed high esters production and significantly high scores for some of the aromatic descriptors that positively influence the sensory profile of sparkling wine. Thus, the use of T. delbrueckii in pure and mixed fermentations is a suitable strategy to further develop the flavour complexity during secondary fermentation of sparkling wines. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Saccharomyces cerevisiae of palm wine-enhanced ethanol production by using mutagens

    International Nuclear Information System (INIS)

    Uma, V.; Polasa, H.

    1990-01-01

    The newly isolated Saccharomyces cerevisiae of palm wine produced enhanced amounts of ethanol when cells were UV-irradiated and treated with N-methyl-N-nitro-N-nitrosoguanidine. A further increase of ethanol was observed in yeast extract, peptone, dextrose medium fortified with yeast extract, skimmed milk and soya flour. (author). 9 refs

  2. Development of defined mixed-culture fungal fermentation starter granulate for controlled production of rice wine

    NARCIS (Netherlands)

    Ngo Thi Phuong Dung, N.T.P.; Rombouts, F.M.; Nout, M.J.R.

    2005-01-01

    As a first step in the development of defined fungal starter granules for controlled winemaking from purple glutinous rice, the interaction of moulds and yeasts isolated from Vietnamese rice wine starters and the effect of some representative oriental herbs on the growth of moulds and yeasts were

  3. Wine tourism in Italy

    Directory of Open Access Journals (Sweden)

    Cinelli Colombini D

    2015-04-01

    Full Text Available Donatella Cinelli Colombini Orcia Doc Wine Consortium, Rocca d’Orcia , Italy Abstract: This text includes the history of wine tourism in Italy since 1993, when the first edition of the event “Cantine Aperte” (Open Cellars, Wine Day, took place. The movement grew from the initial 25 wineries to the 21,000 that participate today in opening their doors to the public, while visitors grew in numbers from a couple of hundred, 20 years ago, to the current 4 to 6 million. Wine tourists can be divided into four main groups: wine tourists by chance, classic wine tourists, talent scouts, and lovers of luxury. Each group is examined according to its consumption, its conduct, and its expectations. Wine tourism in Italy boasts around 170 territorial networks: “Strade del Vino” (wine routes regulated by law. After an initial pioneer phase during which preexisting wineries adapted to the growing number of tourists, modern-day wineries were created with bespoke areas for the welcoming of visitors. Wineries in Italy can be classified into the following main types: “functional wineries” that concentrate on productive efficiency; “cathedrals” – renovated historic buildings or modern “starchitecture” designs in which esthetics play an important role; wineries with a “strong identity” linked to the owner or wine producer with the special imprint of his or her personal wine making passion. Other features of Italian wine territories such as food and wellness centers not to speak of the ever present cultural heritage also play a part in attracting wine tourists. Lastly, an evaluation is made of business and communication aspects with a specific reference to the use of the web. Keywords: wine tourism, Italian wineries, winery tours, wine roads of Italy

  4. Mapping of wine industry

    Directory of Open Access Journals (Sweden)

    Віліна Пересадько

    2016-10-01

    Full Text Available Having reviewed a variety of approaches to understanding the essence of wine industry, having studied the modern ideas about the future of wine industry, having analyzed more than 50 maps from the Internet we have set the trends and special features of wine industry mapping in the world, such as: - the vast majority of maps displays the development of the industry at regional or national level, whereas there are practically no world maps; - wine-growing regions are represented on maps very unevenly; - all existing maps of the industry could be classified as analytical ascertaining inventory type; - the dominant ways of cartographic representation are area method and qualitative background method, sign method and collation maps are rarely used; - basically all the Internet maps have low quality as they are scanned images with poor resolution; - the special feature of maps published lately is lack of geographical basis (except for state borders and coastline. We created wine production and consumption world map «Wine Industry» in the scale of 1:60 000 000 with simple geographical basis (state names, state borders, major rivers, coastline. It was concluded that from the methodological point of view it is incorrect not to show geographical basis on maps of wine industry. Analysis of this map allowed us to identify areas of traditional wine-making, potential wine-making areas and countries which claim to be the world leaders in the field of wine production. We found disbalans between wine production and wine consumption - increasing wine production in South America, China and the United States and increasing wine consumption (mainly due to the import products in countries where the grape is not the primary agricultural product.

  5. Cellar-Associated Saccharomyces cerevisiae Population Structure Revealed High-Level Diversity and Perennial Persistence at Sauternes Wine Estates

    Science.gov (United States)

    Börlin, Marine; Venet, Pauline; Claisse, Olivier; Salin, Franck

    2016-01-01

    ABSTRACT Three wine estates (designated A, B, and C) were sampled in Sauternes, a typical appellation of the Bordeaux wine area producing sweet white wine. From those wine estates, 551 yeast strains were collected between 2012 and 2014, added to 102 older strains from 1992 to 2011 from wine estate C. All the strains were analyzed through 15 microsatellite markers, resulting in 503 unique Saccharomyces cerevisiae genotypes, revealing high genetic diversity and a low presence of commercial yeast starters. Population analysis performed using Fst genetic distance or ancestry profiles revealed that the two closest wine estates, B and C, which have juxtaposed vineyard plots and common seasonal staff, share more related isolates with each other than with wine estate A, indicating exchange between estates. The characterization of isolates collected 23 years ago at wine estate C in relation to recent isolates obtained at wine estate B revealed the long-term persistence of isolates. Last, during the 2014 harvest period, a temporal succession of ancestral subpopulations related to the different batches associated with the selective picking of noble rotted grapes was highlighted. IMPORTANCE High genetic diversity of S. cerevisiae isolates from spontaneous fermentation on wine estates in the Sauternes appellation of Bordeaux was revealed. Only 7% of all Sauternes strains were considered genetically related to specific commercial strains. The long-term persistence (over 20 years) of S. cerevisiae profiles on a given wine estate is highlighted. PMID:26969698

  6. Utilization of Jamun Fruit (Syzygium cumini for Production of Red Wine

    Directory of Open Access Journals (Sweden)

    Shashikant S. Patil

    2012-07-01

    Full Text Available Jamun (Syzygium cumini fruit was utilized for the production of red wine which is offering lot of health benefits by acting as an effective medicine. The alcohol content of wine varied from 6.62 to 10.25 depending upon the variable concentration of total soluble sugars (7.88 to 10.53% and varying levels of yeast (5, 10, 15 and 20%. Saccharomyces cerevisiae was used in the process of fermentation. The wine that had 8.22% alcohol obtained by fermentation with 10% yeast level, 8.18% TSS (Treatment T2 was considered to be the best acceptable when compared with others (T1, T3 and T4 Treatments. This wine was found to be the best by the panel members with respect to colour, taste, astringency and flavour. The wine that had 6.62% alcohol obtained by fermentation with 5% yeast level, 7.88% TSS was considered to be the least preferred and less acceptable when compared with others. No significant changes were observed in colour and clarity of wine obtained with 5% addition of yeast. However, with 5% addition of yeast, the taste, flavor and astringency attributes of wine were the least preferred when compared with others. The highest test score for taste, flavour and astringency properties was obtained for Treatment (T2. The time required for fermentation was 7 days at 28 ± 20C. The wine obtained with 15% (9.16% alcohol content and 20% (10.25% alcohol content yeast levels were found to have moderately acceptable scores.

  7. δ(15) N from soil to wine in bulk samples and proline.

    Science.gov (United States)

    Paolini, Mauro; Ziller, Luca; Bertoldi, Daniela; Bontempo, Luana; Larcher, Roberto; Nicolini, Giorgio; Camin, Federica

    2016-09-01

    The feasibility of using δ(15) N as an additional isotopic marker able to link wine to its area of origin was investigated. The whole production chain (soil-leaves-grape-wine) was considered. Moreover, the research included evaluation of the effect of the fermentation process, the use of different types of yeast and white and red vinification, the addition of nitrogen adjuvants and ultrasound lysis simulating wine ageing. The δ(15) N of grapes and wine was measured in bulk samples and compounds, specifically in proline, for the first time. Despite isotopic fractionation from soil to wine, the δ(15) N values of leaves, grapes, wine and particularly must and wine proline conserved the variability of δ(15) N in the growing soil. Fermentation and ultrasound treatment did not affect the δ(15) N values of grape must, which was therefore conserved in wine. The addition of inorganic or organic adjuvants was able to influence the δ(15) N of bulk wine, depending on the amount and the difference between the δ(15) N of must and that of the adjuvant. The δ(15) N of wine proline was not influenced by adjuvant addition and is therefore the best marker for tracing the geographical origin of wine. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  8. Effectiveness of chitosan against wine-related microorganisms.

    Science.gov (United States)

    Bağder Elmaci, Simel; Gülgör, Gökşen; Tokatli, Mehmet; Erten, Hüseyin; İşci, Asli; Özçelik, Filiz

    2015-03-01

    The antimicrobial action of chitosan against wine related microorganisms, including Lactobacillus plantarum, Saccharomyces cerevisiae, Oeonococcus oeni, Lactobacillus hilgardii, Brettanomyces bruxellensis, Hanseniaspora uvarum and Zygosaccharomyces bailii was examined in laboratory media. In order to assess the potential applicability of chitosan as a microbial control agent for wine, the effect of chitosan, applied individually and/or in combination with sulphur dioxide (SO2), on the growth of microorganisms involved in various stages of winemaking and on the fermentative performance of S. cerevisiae was investigated. Of the seven wine-related microorganisms studied, S. cerevisiae exhibited the strongest resistance to antimicrobial action of chitosan in laboratory media with a minimum inhibitory concentration (MIC) greater than 2 g/L. L. hilgardii, O. oeni and B. bruxellensis were the most susceptible to chitosan since they were completely inactivated by chitosan at 0.2 g/L. The MIC of chitosan for L. plantarum, H. uvarum and Z. bailii was 2, 0.4 and 0.4 g/L, respectively. In wine experiments, it was found that chitosan had a retarding effect on alcoholic fermentation without significantly altering the viability and the fermentative performance of S. cerevisiae. With regard to non-Saccharomyces yeasts (H. uvarum and Z. bailii) involved in winemaking, the early deaths of these yeasts in mixed cultures with S. cerevisiae were not probably due to the antimicrobial action of chitosan but rather due to ethanol produced by the yeasts. The complex interactions between chitosan and wine ingredients as well as microbial interactions during wine fermentation considerably affect the efficacy of chitosan. It was concluded that chitosan was worthy of further investigation as an alternative or complementary preservative to SO2 in wine industry.

  9. Factors influencing the aroma composition of Chardonnay wines.

    Science.gov (United States)

    Gambetta, Joanna M; Bastian, Susan E P; Cozzolino, Daniel; Jeffery, David W

    2014-07-16

    Chardonnay is one of the oldest and most widely distributed wine grape cultivars and is of commercial importance for the world's wine-producing nations. It is an extremely flexible variety that has adapted to different regions with varied weather and soil characteristics. Somewhat uniquely among white wines, Chardonnay lends itself to a wide variety of production styles, which can be tailored to the target market. Techniques such as skin maceration, barrel and stainless steel fermentation, use of selected or indigenous yeasts, malolactic fermentation, and aging in barrels with or without lees are all applicable and lead to different compositional outcomes. A number of research papers have been published with a view to understanding Chardonnay composition and quality as well as the impact of different enological techniques on the final product. This review summarizes current knowledge, explaining the influence of viticultural and production techniques on aroma composition, and poses directions for further research into Chardonnay wines.

  10. 27 CFR 24.215 - Wine or wine products not for beverage use.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Wine or wine products not... AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.215 Wine or wine products not for beverage use. (a) General. Wine, or wine products made from wine...

  11. Wine and endothelial function.

    Science.gov (United States)

    Caimi, G; Carollo, C; Lo Presti, R

    2003-01-01

    In recent years many studies have focused on the well-known relationship between wine consumption and cardiovascular risk. Wine exerts its protective effects through various changes in lipoprotein profile, coagulation and fibrinolytic cascades, platelet aggregation, oxidative mechanisms and endothelial function. The last has earned more attention for its implications in atherogenesis. Endothelium regulates vascular tone by a delicate balancing among vasorelaxing (nitric oxide [NO]) and vasoconstrincting (endothelins) factors produced by endothelium in response to various stimuli. In rat models, wine and other grape derivatives exerted an endothelium-dependent vasorelaxing capacity especially associated with the NO-stimulating activity of their polyphenol components. In experimental conditions, reservatrol (a stilbene polyphenol) protected hearts and kidneys from ischemia-reperfusion injury through antioxidant activity and upregulation of NO production. Wine polyphenols are also able to induce the expression of genes involved in the NO pathway within the arterial wall. The effects of wine on endothelial function in humans are not yet clearly understood. A favorable action of red wine or dealcoholized wine extract or purple grape juice on endothelial function has been observed by several authors, but discrimination between ethanol and polyphenol effects is controversial. It is, however likely that regular and prolonged moderate wine drinking positively affects endothelial function. The beneficial effects of wine on cardiovascular health are greater if wine is associated with a healthy diet. The most recent nutritional and epidemiologic studies show that the ideal diet closely resembles the Mediterranean diet.

  12. Tapping into yeast diversity.

    Science.gov (United States)

    Fay, Justin C

    2012-11-01

    Domesticated organisms demonstrate our capacity to influence wild species but also provide us with the opportunity to understand rapid evolution in the context of substantially altered environments and novel selective pressures. Recent advances in genetics and genomics have brought unprecedented insights into the domestication of many organisms and have opened new avenues for further improvements to be made. Yet, our ability to engineer biological systems is not without limits; genetic manipulation is often quite difficult. The budding yeast, Saccharomyces cerevisiae, is not only one of the most powerful model organisms, but is also the premier producer of fermented foods and beverages around the globe. As a model system, it entertains a hefty workforce dedicated to deciphering its genome and the function it encodes at a rich mechanistic level. As a producer, it is used to make leavened bread, and dozens of different alcoholic beverages, such as beer and wine. Yet, applying the awesome power of yeast genetics to understanding its origins and evolution requires some knowledge of its wild ancestors and the environments from which they were derived. A number of surprisingly diverse lineages of S. cerevisiae from both primeval and secondary forests in China have been discovered by Wang and his colleagues. These lineages substantially expand our knowledge of wild yeast diversity and will be a boon to elucidating the ecology, evolution and domestication of this academic and industrial workhorse.

  13. Effect of salt hyperosmotic stress on yeast cell viability

    Directory of Open Access Journals (Sweden)

    Logothetis Stelios

    2007-01-01

    Full Text Available During fermentation for ethanol production, yeasts are subjected to different kinds of physico-chemical stresses such as: initially high sugar concentration and low temperature; and later, increased ethanol concentrations. Such conditions trigger a series of biological responses in an effort to maintain cell cycle progress and yeast cell viability. Regarding osmostress, many studies have been focused on transcriptional activation and gene expression in laboratory strains of Saccharomyces cerevisiae. The overall aim of this present work was to further our understanding of wine yeast performance during fermentations under osmotic stress conditions. Specifically, the research work focused on the evaluation of NaCl-induced stress responses of an industrial wine yeast strain S. cerevisiae (VIN 13, particularly with regard to yeast cell growth and viability. The hypothesis was that osmostress conditions energized specific genes to enable yeast cells to survive under stressful conditions. Experiments were designed by pretreating cells with different sodium chloride concentrations (NaCl: 4%, 6% and 10% w/v growing in defined media containing D-glucose and evaluating the impact of this on yeast growth and viability. Subsequent fermentation cycles took place with increasing concentrations of D-glucose (20%, 30%, 40% w/v using salt-adapted cells as inocula. We present evidence that osmostress induced by mild salt pre-treatments resulted in beneficial influences on both cell viability and fermentation performance of an industrial wine yeast strain.

  14. WINE MARKETS IN CENTRAL EUROPE

    Directory of Open Access Journals (Sweden)

    Š BOJNEC

    2007-04-01

    Full Text Available This paper analyses the tendencies of grapes growing, wine trading and wine price competitiveness in Central European region. Croatia is net exporter of wines, Hungary is net exporter of grapes and wines, and Austria, Slovakia, and Slovenia are net importers of grapes and wines. Reductions in vineyards and increase in yields are found for Austria, Hungary, and Slovakia. More stable developments in vineyards, but decline in yields, are found for Croatia and Slovenia. Grape production increases in Austria, remains stable in Croatia, explores annual oscillations in Hungary, and declines in Slovakia and Slovenia. Export-to-import wine prices deteriorate for Austria and Hungary with most recent stabilization and price similarity, which hold also for Slovakia. Slovenian export-to-import wine prices are unstable, while Croatia experiences a bit higher export than import wine prices. Wine marketing, wine brand image of quality, and wine tourism are seen as tools to improve competitiveness in the wine sector.

  15. Antimicrobial activity of yeasts against some pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Gamal Younis

    2017-08-01

    Full Text Available Aim: This study was designed to isolate and identify yeast species from milk and meat products, and to test their antimicrobial activity against some bacterial species. Materials and Methods: A total of 160 milk and meat products samples were collected from random sellers and super markets in New Damietta city, Damietta, Egypt. Samples were subjected to yeast isolation procedures and tested for its antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. In addition, all yeast species isolates were subjected to polymerase chain reaction (PCR for detection of khs (kievitone hydratase and pelA (pectate degrading enzyme genes. Results: The recovery rate of yeasts from sausage was 20% (2/10 followed by kareish cheese, processed cheese, and butter 10% (1/10 each as well as raw milk 9% (9/100, and fruit yoghurt 30% (6/20. Different yeast species were recovered, namely, Candida kefyr (5 isolates, Saccharomyces cerevisiae (4 isolates, Candida intermedia (3 isolates, Candida tropicalis (2 isolates, Candida lusitaniae (2 isolates, and Candida krusei (1 isolate. khs gene was detected in all S. cerevisiae isolates, however, pelA gene was not detected in all identified yeast species. Antimicrobial activity of recovered yeasts against the selected bacterial species showed high activity with C. intermedia against S. aureus and E. coli, C. kefyr against E. coli, and C. lusitaniae against S. aureus. Moderate activities were obtained with C. tropicalis, C. lusitaniae, and S. cerevisiae against E. coli; meanwhile, all the tested yeasts revealed a very low antimicrobial activity against P. aeruginosa. Conclusion: The obtained results confirmed that some kinds of yeasts have the ability to produce antimicrobial compounds that could inhibit some pathogenic and spoilage bacteria and these antimicrobial activity of yeasts enables them to be one of the novel agents in controlling spoilage of food.

  16. A mechanistic approach to postirradiation spoilage kinetics of fish

    International Nuclear Information System (INIS)

    Tukenmez, I.

    2004-01-01

    Full text: In order to simulate postirradiation spoilage of fish, the mechanistic aspects of the growth of surviving microorganisms during chill storage and their product formation in irradiated fish were analyzed. Anchovy (Engraulis encrasicholus) samples those unirradiated and irradiated at 1, 2 and 3 kGy doses of gamma radiation were stored at +2 o C for 21 days. Total bacterial counts (TBC) and trimethylamine (TMA) analysis of the samples were done periodically during storage. Depending on the proposed spoilage mechanism, kinetic model equations were derived. By using experimental data of TBC and TMA in the developed model, the postirradiation spoilage parameters including growth rate constant, inital and maximum attainable TBC, lag time and TMA yield were evaluated and microbial spoilage of fish was simulated for postirradiation storage. Shelf life of irradiated fish was estimated depending on the spoilage kinetics. Dose effects on the kinetic parameters were analyzed. It is suggested that the kinetic evaluation method developed in this study may be used for quality assessment, shelf life determination and dose optimization for radiation preservation of fish

  17. Effect of sequential fermentations and grape cultivars on volatile compounds and sensory profiles of Danish wines.

    Science.gov (United States)

    Liu, Jing; Arneborg, Nils; Toldam-Andersen, Torben B; Petersen, Mikael A; Bredie, Wender Lp

    2017-08-01

    There has been an increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. In this work, three non-Saccharomyces yeast strains (Metschnikowia viticola, Metschnikowia fructicola and Hanseniaspora uvarum) indigenously isolated in Denmark were used in sequential fermentations with S. cerevisiae on three cool-climate grape cultivars, Bolero, Rondo and Regent. During the fermentations, the yeast growth was determined as well as key oenological parameters, volatile compounds and sensory properties of finished rosé wines. The different non-Saccharomyces strains and cool-climate grape cultivars produced wines with a distinctive aromatic profile. A total of 67 volatile compounds were identified, including 43 esters, 14 alcohols, five acids, two ketones, a C13-norisoprenoid, a lactone and a sulfur compound. The use of M. viticola in sequential fermentation with S. cerevisiae resulted in richer berry and fruity flavours in wines. The sensory plot showed a more clear separation among wine samples by grape cultivars compared with yeast strains. Knowledge on the influence of indigenous non-Saccharomyces strains and grape cultivars on the flavour generation contributed to producing diverse wines in cool-climate wine regions. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  18. Mapping of wine industry

    OpenAIRE

    Віліна Пересадько; Надія Максименко; Катерина Біла

    2016-01-01

    Having reviewed a variety of approaches to understanding the essence of wine industry, having studied the modern ideas about the future of wine industry, having analyzed more than 50 maps from the Internet we have set the trends and special features of wine industry mapping in the world, such as: - the vast majority of maps displays the development of the industry at regional or national level, whereas there are practically no world maps; - wine-growing regions are represented on maps very un...

  19. Bioactive proteins against pathogenic and spoilage bacteria

    Directory of Open Access Journals (Sweden)

    Mahmoud Z. Sitohy

    2014-10-01

    Full Text Available Background: It is likely that both human nutrition and the nutrition of livestock are benefited by the presence of bioactive proteins within their respective diet regimes. Bioactive proteins have been defined as specific protein fragments that positively impact bodily functions or conditions and may, ultimately, influence overall human health. The ingestion of bioactive proteins may have an effect on the major body systems—namely, the cardiovascular, digestive, immune and nervous systems. According to their functional properties, bioactive proteins may be classified as antimicrobial, antithrombotic, antihypertensive, opioid, immune-modulatory, mineral binding and anti-oxidative. There are many examples of biologically active food proteins and active peptides that can be obtained from various food protein sources. They have a physiological significance beyond the pure nutritional requirements; in other wordsthey have the acquisition of nitrogen for normal growth and maintenance. Objective: This study aims to specify and characterize the extent and mode of action of bioactive proteins in their native form, (glycinin, glycinin basic sub-unit and β-conglycinin against specific main pathogens (Listeria monocytogenes, Escherichia coli O157:H7 and Salmonella enterica serovar Enteritidis. We will be using standard media while identifying the main constituents responsible for this action. Methods: Glycinin, basic sub-unit and β-conglycinin were isolated from soybean protein and tested for their antimicrobial action against pathogenic and spoilage bacteria, They were thencompared to the properties of penicillin. Methylated soybean protein and also methylated chickpea protein (MSP and MCP, with isoelectric points around pI 8, were prepared by esterifying. 83 % of their free carboxyl groups and their interactions with Gram positive and Gram negative bacteria were examined. Results: The three divisions of cationic proteins exhibited antibacterial

  20. Influence of Saccharomyces cerevisiae Strains on General Composition and Sensorial Properties of White Wines Made from Vitis vinifera cv. Albariño

    Directory of Open Access Journals (Sweden)

    Mar Vilanova

    2005-01-01

    Full Text Available Yeast strains contribute to the oenological and sensorial characteristics of the wines they produce. The present study was performed to determine the influence of Saccharomyces cerevisiae strains on the composition and sensorial properties of Albariño wine. The must obtained from Albariño grapes was inoculated with 12 different yeast strains isolated from a single winery in Galicia, Spain. Chemical and sensorial analyses were performed on the final wines, which differed depending on the yeast strain used.

  1. Influence of High Hydrostatic Pressure Technology on Wine Chemical and Sensorial Characteristics: Potentialities and Drawbacks.

    Science.gov (United States)

    Nunes, Cláudia; Santos, Mickael C; Saraiva, Jorge A; Rocha, Sílvia M; Coimbra, Manuel A

    During last years, scientific research on high hydrostatic pressure (HHP) as a nonthermal processing technology for preservation or aging of wine has increased substantially. HHP between 200 and 500MPa is able to inactivate bacteria and yeasts in red and white wines, suggesting that it may be used for wine preservation. However, these treatments have been shown to promote changes on sensorial and physicochemical characteristics in both red and white wines, not immediately in the first month, but along storage. The changes are observed in wine color, aroma, and taste due mainly to reactions of phenolic compounds, sugars, and proteins. These reactions have been associated with those observed during wine aging, leading to aged-like wine characteristics perceived by sensorial analysis. This chapter will present the influence of HHP technology on wine chemical and sensorial characteristics, criticaly discussing its potentialities and drawbacks. The appropriate use of HHP, based on the scientific knowledge of the reactions occuring in wine promoted by HHP, will allow to exploit this technology for wine production achieving distinct characteristics to address particular market and consumer demands. © 2017 Elsevier Inc. All rights reserved.

  2. Foliar nitrogen application in Cabernet Sauvignon vines: Effects on wine flavonoid and amino acid content.

    Science.gov (United States)

    Gutiérrez-Gamboa, Gastón; Garde-Cerdán, Teresa; Portu, Javier; Moreno-Simunovic, Yerko; Martínez-Gil, Ana M

    2017-06-01

    Wine quality greatly depends on its chemical composition. Among the most important wine chemical compounds, flavonoids are the major contributors to wine organoleptic properties while amino acids have a huge impact on fermentation development and wine volatile profile. Likewise, nitrogen applications are known to have an impact on wine composition. Therefore, the aim of this work was to study the effects of foliar nitrogen applications on wine flavonoid and amino acid composition. The experiment involved five foliar nitrogen applications at veraison time: urea (Ur), urea plus sulphur (Ur+S), arginine (Arg), and two commercial fertilizers Nutrimyr Thiols (NT) and Basfoliar Algae (BA). The results showed that nitrogen foliar treatments decreased wine flavonoid content although the effect varied according to each treatment. This could be related to a low vine nitrogen requirement, since must yeast assimilable nitrogen (YAN) was above acceptable threshold values for all samples. With regard to wine amino acid content, all treatments except for Ur increased its values after the applications. Finally, foliar nitrogen treatments greatly influenced wine composition. Among them, urea seemed to exert the most negative effect on both phenolics and amino acids. In addition, an inverse relationship between wine amino acid content and flavonol concentration was exhibited. Copyright © 2017. Published by Elsevier Ltd.

  3. Wine consumers' subjective responses to wine mouthfeel and understanding of wine body.

    Science.gov (United States)

    Niimi, Jun; Danner, Lukas; Li, Luxing; Bossan, Hélène; Bastian, Susan E P

    2017-09-01

    Wine mouthfeel is considered important for wine quality by experts, while consumers understanding of mouthfeel and the role of wine body in their wine choice is unknown. One experiment determined the influence of intrinsic wine mouthfeel on consumers' wine liking and emotions, and the other, how consumers understand the term wine body. The first experiment used a 2 astringency level×2 body level experimental design. The samples were base wine with; nothing added (control), added xanthan gum (for increased body), added grape seed extract (GSE, for increased astringency), and with both added xanthan gum and GSE. The consumer taste trial (n=112) indicated that wine with increased body did not influence wine liking and emotions; while increased astringency decreased liking and elicited more intense negative emotions. The second experiment examined consumers' knowledge of wine body through an online survey (n=136). Consumers described wine body most frequently using words such as flavour, fullness, and strength. Wine body was therefore understood by consumers predominantly as a holistic multi-sensory perception of flavour. Wine flavour was indicated by consumers to be the most important factor driving purchase decisions followed by balance of flavours and wine body. It is crucial that wine professionals carefully communicate wine characteristics to consumers to prevent possible misunderstandings such as the meaning of wine body and as a result better meet consumer expectations. In future, the term body may benefit from a clearer definition for academic research as well as industry. Copyright © 2017. Published by Elsevier Ltd.

  4. Growth temperature exerts differential physiological and transcriptional responses in laboratory and wine strains of Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Pizarra, Francisco J.; Jewett, Michael Christopher; Nielsen, Jens

    2008-01-01

    Laboratory strains of Saccharomyces cerevisiae have been widely used as a model for studying eukaryotic cells and mapping the molecular mechanisms of many different human diseases. Industrial wine yeasts, on the other hand, have been selected on the basis of their adaptation to stringent environm......Laboratory strains of Saccharomyces cerevisiae have been widely used as a model for studying eukaryotic cells and mapping the molecular mechanisms of many different human diseases. Industrial wine yeasts, on the other hand, have been selected on the basis of their adaptation to stringent...... environmental conditions and the organoleptic properties that they confer to wine. Here, we used a two-factor design to study the responses of a standard laboratory strain, CEN.PK113-7D, and an industrial wine yeast strain, EC1118, to growth temperatures of 15 degrees C and 30 degrees C in nitrogen......-limited, anaerobic, steady-state chemostat cultures. Physiological characterization revealed that the growth temperature strongly impacted the biomass yield of both strains. Moreover, we found that the wine yeast was better adapted to mobilizing resources for biomass production and that the laboratory yeast...

  5. Between science and industry-applied yeast research.

    Science.gov (United States)

    Korhola, Matti

    2018-03-01

    I was fortunate to enter yeast research at the Alko Research Laboratories with a strong tradition in yeast biochemistry and physiology studies. At the same time in the 1980s there was a fundamental or paradigm change in molecular biology research with discoveries in DNA sequencing and other analytical and physical techniques for studying macromolecules and cells. Since that time biotechnological research has expanded the traditional fermentation industries to efficient production of industrial and other enzymes and specialty chemicals. Our efforts were directed towards improving the industrial production organisms: minerals enriched yeasts (Se, Cr, Zn) and high glutathione content yeast, baker´s, distiller´s, sour dough and wine yeasts, and the fungal Trichoderma reesei platform for enzyme production. I am grateful for the trust of my colleagues in several leadership positions at the Alko Research Laboratories, Yeast Industry Platform and at the international yeast community.

  6. 27 CFR 27.42 - Wines.

    Science.gov (United States)

    2010-04-01

    ... TREASURY LIQUORS IMPORTATION OF DISTILLED SPIRITS, WINES, AND BEER Tax On Imported Distilled Spirits, Wines, and Beer Wines § 27.42 Wines. All wines (including imitation, substandard, or artificial wine, and... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Wines. 27.42 Section 27.42...

  7. Non-anthocyanin polyphenolic transformation by native yeast and bacteria co-inoculation strategy during vinification.

    Science.gov (United States)

    Devi, Apramita; Archana, Kodira Muthanna; Bhavya, Panikuttria Kuttappa; Anu-Appaiah, Konerira Aiyappaa

    2018-02-01

    Co-inoculation has been adapted by many wine-producing countries because it enhances the success of malolactic fermentation and reduces the fermentation cost, as well as time. However, wine phenolics have been sparsely highlighted during co-inoculation, even though polyphenols are an important parameter affecting wine colour, astringency and aroma. In the present study, we investigated the impact of co-inoculation on non-anthocyanin polyphenol profile for two different grape varieties. Co-inoculation of native yeast strain (AAV2) along with Oenococcus oeni was adapted for Cabernet Sauvignon and Shiraz wine. It was observed that the co-inoculation had minimal yet significant impact on the phenolic composition of wines for both the grape varieties. Color loss, as well as fruity aroma development, was observed in co-inoculated wines. The wines were on a par with the commercial wine, as well as wines without malolactic fermentation, in terms of phenolic compounds and overall organoleptic acceptance. Principal component analysis and hierarchical cluster analysis further suggested that the varietal influence on phenolic composition was dominating compared to inoculation strategies. Among the varieties, the inoculation strategies have significantly influenced the Cabernet wines compared to Shiraz wines. The results of the present study demonstrate that the phenolic compounds are not drastically affected by metabolic activities of malolactic bacteria during co-inoculation and, hence, are equally suitable for wine fermentation. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  8. Seafood Spoilage Predictor - development and distribution of a product specific application software

    DEFF Research Database (Denmark)

    Dalgaard, Paw; Buch, P.; Silberg, Steen

    2002-01-01

    To allow shelf-life prediction of a range of products, the Seafood Spoilage Predictor (SSP) software has been developed to include both kinetic models for growth of specific spoilage microorganisms and empirical relative rates of spoilage models. SSP can read and evaluate temperature profile data...

  9. Microoxidation in wine production.

    Science.gov (United States)

    Kilmartin, Paul A

    2010-01-01

    Microoxygenation (MOX) is now widely applied for the maturation of red wines as an alternative to barrel aging. The proposed improvements in wine quality arising from MOX include color stabilization, removal of unwanted off-odors, and improvements in wine mouthfeel. In this review, an outline is provided of oxygenation systems, particularly microbullage and polymer membrane delivery, and of the current understanding of wine oxidation processes. A summary of the results from published studies into red wine MOX is then provided, beginning with observations on O(2) and acetaldehyde accumulation, and the moderating effect of added sulfur dioxide. Effects upon red wine color, particularly the more rapid formation of polymeric pigments and higher color retention, have been consistently demonstrated in MOX studies, along with further effects on specific polyphenol compounds. A few reports have recently examined the effect of MOX on red wine aromas, but these have yet to identify compounds that consistently change in a manner that would explain sensory observations regarding a lowering of herbaceous and reductive odors. Likewise, tannin analyses have been undertaken in several studies, but explanations of the decline in wine astringency remain to be developed. The accelerated growth of unwanted microorganisms has also been examined in a limited number of studies, but no major problems have been identified in this area. Copyright © 2010 Elsevier Inc. All rights reserved.

  10. Maceration enzymes and mannoproteins: a possible strategy to increase colloidal stability and color extraction in red wines.

    Science.gov (United States)

    Guadalupe, Zenaida; Palacios, Antonio; Ayestaran, Belén

    2007-06-13

    Different strategies were adopted to achieve increases in color stability in Tempranillo wines: (i) addition of maceration enzymes directly to the must, (ii) addition of commercial mannoproteins to the must, and (iii) inoculation of must with yeast overexpressed of mannoproteins. The addition of enzymes favored color extraction, and the wines obtained presented higher values of wine color, color intensity, bisulfite-stable color, and visually enhanced color intensity. The enzyme hydrolytic activity produced an increase in the acid polysaccharide content and polyphenol index and yielded to wines with more astringency, tannin, and length. Added mannoproteins had clearer effects on the analyzed parameters than yeast. Contrary to what may be thought, mannoproteins did not maintain the extracted polyphenols in colloidal dispersion and neither ensured color stability. These compounds clearly modified the gustative structure of the wines, enhancing the sweetness and roundness.

  11. Effect of Temperature on the Prevalence of Saccharomyces Non cerevisiae Species against a S. cerevisiae Wine Strain in Wine Fermentation: Competition, Physiological Fitness, and Influence in Final Wine Composition

    Science.gov (United States)

    Alonso-del-Real, Javier; Lairón-Peris, María; Barrio, Eladio; Querol, Amparo

    2017-01-01

    Saccharomyces cerevisiae is the main microorganism responsible for the fermentation of wine. Nevertheless, in the last years wineries are facing new challenges due to current market demands and climate change effects on the wine quality. New yeast starters formed by non-conventional Saccharomyces species (such as S. uvarum or S. kudriavzevii) or their hybrids (S. cerevisiae x S. uvarum and S. cerevisiae x S. kudriavzevii) can contribute to solve some of these challenges. They exhibit good fermentative capabilities at low temperatures, producing wines with lower alcohol and higher glycerol amounts. However, S. cerevisiae can competitively displace other yeast species from wine fermentations, therefore the use of these new starters requires an analysis of their behavior during competition with S. cerevisiae during wine fermentation. In the present study we analyzed the survival capacity of non-cerevisiae strains in competition with S. cerevisiae during fermentation of synthetic wine must at different temperatures. First, we developed a new method, based on QPCR, to quantify the proportion of different Saccharomyces yeasts in mixed cultures. This method was used to assess the effect of competition on the growth fitness. In addition, fermentation kinetics parameters and final wine compositions were also analyzed. We observed that some cryotolerant Saccharomyces yeasts, particularly S. uvarum, seriously compromised S. cerevisiae fitness during competences at lower temperatures, which explains why S. uvarum can replace S. cerevisiae during wine fermentations in European regions with oceanic and continental climates. From an enological point of view, mixed co-cultures between S. cerevisiae and S. paradoxus or S. eubayanus, deteriorated fermentation parameters and the final product composition compared to single S. cerevisiae inoculation. However, in co-inoculated synthetic must in which S. kudriavzevii or S. uvarum coexisted with S. cerevisiae, there were fermentation

  12. Virgin olive oil yeasts: A review.

    Science.gov (United States)

    Ciafardini, Gino; Zullo, Biagi Angelo

    2018-04-01

    This review summarizes current knowledge on virgin olive oil yeasts. Newly produced olive oil contains solid particles and micro drops of vegetation water in which yeasts reproduce to become the typical microbiota of olive oil. To date, about seventeen yeast species have been isolated from different types of olive oils and their by-products, of which six species have been identified as new species. Certain yeast species contribute greatly to improving the sensorial characteristics of the newly produced olive oil, whereas other species are considered harmful as they can damage the oil quality through the production of unpleasant flavors and triacylglycerol hydrolysis. Studies carried out in certain yeast strains have demonstrated the presence of defects in olive oil treated with Candida adriatica, Nakazawaea wickerhamii and Candida diddensiae specific strains, while other olive oil samples treated with other Candida diddensiae strains were defect-free after four months of storage and categorized as extra virgin. A new acetic acid producing yeast species, namely, Brettanomyces acidodurans sp. nov., which was recently isolated from olive oil, could be implicated in the wine-vinegary defect of the product. Other aspects related to the activity of the lipase-producing yeasts and the survival of the yeast species in the flavored olive oils are also discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Association between modification of phenolic profiling and development of wine color during alcohol fermentation.

    Science.gov (United States)

    Li, Si-Yu; Liu, Pei-Tong; Pan, Qiu-Hong; Shi, Ying; Duan, Chang-Qing

    2015-04-01

    To solve the problem of wine color instability in western China, different additives (the maceration enzymes Vinozym G and Ex-color, yeasts VR5 and Red Star, and commercial tannins) were added during alcoholic fermentation of Syrah (Vitis vinifera L.). The phenolic profile and color characteristics of wine were examined using high performance liquid chromatography mass spectrometry and CIELAB, respectively. The results showed that the combination of the enzyme Ex-color with the Red Star yeast eased the release of non-anthocyanins from grape berries into wine, whereas the use of enzyme Vinozym G and VR5 yeast enhanced the concentration of anthocyanins and achieved a higher red hue (a* value) and a lower yellow hue (b* value) in the wine. The addition of commercial tannins greatly promoted the level of gallic acid in the wine and led to a relatively higher concentration of anthocyanins. Partial least-squares regression analysis was used to find out the major phenolics, which were in close relation with color parameters; principal component analysis was used to evaluate the contribution of different winemaking techniques to wine color. The combination of these 2 analytic methods indicated that Vinozym G and VR5 yeast together with commercial tannins should be an appropriate combination to enhance the stability of wine color during alcohol fermentation, which was related to a significant increase in cyanidin-3-O-(6-O-acetyl)-glucoside, cyanidin-3-O-(6-O-coumaryl)-glucoside, trans-peonidin-3-O-(6-O-coumaryl)-glucoside, trans-malvidin-3-O-(6-O-coumaryl)-glucoside, and malvidin-3-O-(6-O-acetyl)-glucoside-pyruvic acid, all of which played an important role in stabilizing wine color. © 2015 Institute of Food Technologists®

  14. Metabolic strategies of beer spoilage lactic acid bacteria in beer.

    Science.gov (United States)

    Geissler, Andreas J; Behr, Jürgen; von Kamp, Kristina; Vogel, Rudi F

    2016-01-04

    Beer contains only limited amounts of readily fermentable carbohydrates and amino acids. Beer spoilage lactic acid bacteria (LAB) have to come up with metabolic strategies in order to deal with selective nutrient content, high energy demand of hop tolerance mechanisms and a low pH. The metabolism of 26 LAB strains of 6 species and varying spoilage potentialwas investigated in order to define and compare their metabolic capabilities using multivariate statistics and outline possible metabolic strategies. Metabolic capabilities of beer spoilage LAB regarding carbohydrate and amino acids did not correlate with spoilage potential, but with fermentation type (heterofermentative/homofermentative) and species. A shift to mixed acid fermentation by homofermentative (hof) Pediococcus claussenii and Lactobacillus backii was observed as a specific feature of their growth in beer. For heterofermentative (hef) LAB a mostly versatile carbohydrate metabolism could be demonstrated, supplementing the known relevance of organic acids for their growth in beer. For hef LAB a distinct amino acid metabolism, resulting in biogenic amine production, was observed, presumably contributing to energy supply and pH homeostasis.

  15. Spoilage fungi and their mycotoxins in commercially marketed chestnuts

    DEFF Research Database (Denmark)

    Overy, David Patrick; Seifert, K.A.; Savard, M.E.

    2003-01-01

    A nationwide survey was carried out to assess mould spoilage of Castanea sativa nuts sold in Canadian grocery stores in 1998-99. Morphological and cultural characters, along with secondary metabolite profiles derived from thin-layer chromatography, were used to sort and identify fungi cultured from...

  16. Microorganisms associated with the spoilage of avocado pear ...

    African Journals Online (AJOL)

    The microorganisms associated with the spoilage of Avocado pear, Persea americana fruits, purchased fresh from various markets in Benin City were investigated. The pour plate method was used for the isolation. A total of nine species of microorganisms were isolated and identified in this study. They comprise of seven ...

  17. Spoilage potential of Paenibacillussp. in Brazilian raw milk

    Directory of Open Access Journals (Sweden)

    José Carlos Ribeiro Júnior

    2016-04-01

    Full Text Available ABSTRACT: Bacterial spores are widespread in the environment and can contaminate milk. Spores are resistant to thermal conditions and your germination reduces milk shelf-life because the aerobic bacteria that are sporulated produce proteases and lipases. The aim of this study was identify Paenibacillus sp., the spoilage microbiota, arising from the germination of spores in raw milk and your spoilage potential. Twenty different milk samples were treated at 80°C/12min and plated to isolate spore-forming bacteria. These strains were picked in milk agar and tributyrin agar for verification of their potential proteolytic and lipolytic activities, respectively. Amplification and sequencing of the 16S rRNA gene of the strains for identification by similarity to the DNA sequences deposited in GenBank was performed. One hundred and thirty-seven isolates were obtained, of which 40 (29.2% showed spoilage activity for milk. Of these, three (7.5% were identified as strains of Paenibacillus sp., and all were lipolytic. Paenibacillus sp. have been identified as primarily responsible for the spoilage of pasteurized milk with a long shelf-life in other countries. To increase the shelf-life of Brazilian pasteurized milk, it is important to identify the sporulated microbes to determine their origin and to control the contamination of milk by vegetative forms such as spores.

  18. Bacterial spoilage of meat and cured meat products

    NARCIS (Netherlands)

    Borch, E.; Kant-Muermans, M.L.T.; Blixt, Y.

    1996-01-01

    The influence of environmental factors (product composition and storage conditions) on the selection, growth rate and metabolic activity of the bacterial flora is presented for meat (pork and beef) and cooked, cured meat products. The predominant bacteria associated with spoilage of refrigerated

  19. Rapid measurement of meat spoilage using fluorescence spectroscopy

    Science.gov (United States)

    Wu, Binlin; Dahlberg, Kevin; Gao, Xin; Smith, Jason; Bailin, Jacob

    2017-02-01

    Food spoilage is mainly caused by microorganisms, such as bacteria. In this study, we measure the autofluorescence in meat samples longitudinally over a week in an attempt to develop a method to rapidly detect meat spoilage using fluorescence spectroscopy. Meat food is a biological tissue, which contains intrinsic fluorophores, such as tryptophan, collagen, nicotinamide adenine dinucleotide (NADH) and flavin adenine dinucleotide (FAD) etc. As meat spoils, it undergoes various morphological and chemical changes. The concentrations of the native fluorophores present in a sample may change. In particular, the changes in NADH and FAD are associated with microbial metabolism, which is the most important process of the bacteria in food spoilage. Such changes may be revealed by fluorescence spectroscopy and used to indicate the status of meat spoilage. Therefore, such native fluorophores may be unique, reliable and nonsubjective indicators for detection of spoiled meat. The results of the study show that the relative concentrations of all above fluorophores change as the meat samples kept in room temperature ( 19° C) spoil. The changes become more rapidly after about two days. For the meat samples kept in a freezer ( -12° C), the changes are much less or even unnoticeable over a-week-long storage.

  20. Interactions of Condensed Tannins with Saccharomyces cerevisiae Yeast Cells and Cell Walls: Tannin Location by Microscopy.

    Science.gov (United States)

    Mekoue Nguela, Julie; Vernhet, Aude; Sieczkowski, Nathalie; Brillouet, Jean-Marc

    2015-09-02

    Interactions between grape tannins/red wine polyphenols and yeast cells/cell walls was previously studied within the framework of red wine aging and the use of yeast-derived products as an alternative to aging on lees. Results evidenced a quite different behavior between whole cells (biomass grown to elaborate yeast-derived products, inactivated yeast, and yeast inactivated after autolysis) and yeast cell walls (obtained from mechanical disruption of the biomass). Briefly, whole cells exhibited a high capacity to irreversibly adsorb grape and wine tannins, whereas only weak interactions were observed for cell walls. This last point was quite unexpected considering the literature and called into question the real role of cell walls in yeasts' ability to fix tannins. In the present work, tannin location after interactions between grape and wine tannins and yeast cells and cell walls was studied by means of transmission electron microscopy, light epifluorescence, and confocal microscopy. Microscopy observations evidenced that if tannins interact with cell walls, and especially cell wall mannoproteins, they also diffuse freely through the walls of dead cells to interact with their plasma membrane and cytoplasmic components.

  1. Yeast Biodiversity from DOQ Priorat Uninoculated Fermentations

    OpenAIRE

    Padilla, Beatriz; Garc?a-Fern?ndez, David; Gonz?lez, Beatriz; Izidoro, Iara; Esteve-Zarzoso, Braulio; Beltran, Gemma; Mas, Albert

    2016-01-01

    Climate, soil, and grape varieties are the primary characteristics of terroir and lead to the definition of various appellations of origin. However, the microbiota associated with grapes are also affected by these conditions and can leave a footprint in a wine that will be part of the characteristics of terroir. Thus, a description of the yeast microbiota within a vineyard is of interest not only to provide a better understanding of the winemaking process, but also to understand the source of...

  2. Mycoflora and production of wine from fruits of soursop (Annona Muricata L.

    Directory of Open Access Journals (Sweden)

    Raphael N Okigbo

    2008-12-01

    Full Text Available Raphael N Okigbo1, Omokaro Obire21Department of Botany, Nnamdi Azikiwe University, Awka, Anambra State, Nigeria; 2Department of Applied and Environmental Biology, Rivers State University of Science and Technology, Port Harcourt, NigeriaAbstract: An investigation was conducted on the mycoflora associated with the different parts of fresh and rotten fruits of soursop (Annona muricata L. and the potential of using both indigenous yeast flora and commercial yeast extract for wine production. Isolation of fungi and pathogenicity test were carried out with Sabouraud dextrose agar. Mycoflora were more in the rotten fruits than in the fresh fruits. Botryodiplodia theobromae was isolated only from the rotten fruits (skin while Trichoderma viride was isolated only from the fresh fruits. Penicillium sp., was the most dominant in all the fruit part of fresh soursop fruit with Rhizopus stolonifer having the highest percentage occurrence (36.39% in the rotten fruit. Most of the isolated fungi indicated occurrence of such common airborne fungi on soursop fruits and the potential to induce rot in fresh healthy fruits of soursop in storage. Soursop juice was fermented for 10 days and wine was obtained. There was a significant difference (P < 0.05 in the alcoholic content of the wines obtained from the indigenous and commercial yeasts. The wine obtained from the pasteurized, ameliorated soursop juice inoculated with propagated indigenous yeast yielded the highest alcoholic content. Based on the level of the nutritional composition of soursop juice, the ability to support yeast growth, the high alcoholic content and palatability of the wine, the Annona muricata is good source for wine production and single-cell protein.Keywords: fermentation, fruit yeast, fungi, incidence, rot

  3. Fermentation of an Aromatized Wine-Based Beverage with Sambucus nigra L. Syrup (after Champenoise Method

    Directory of Open Access Journals (Sweden)

    Teodora Emilia Coldea

    2015-11-01

    Full Text Available The sparkling wine based beverage with elderflower (Sambucus nigra L. syrup presented improved sensorial characteristics. White wine used was Fetească regală variety, obtained in Micro winery of University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca. Elderflower syrup was prepared without thermal treatment, but was pasteurised before its addition to wine. Elderflower have many health benefits, such as diuretic, diaphoretic, or antioxidant activity. In this study it was used elderflower syrup both to improve the product s sensorial properties, and for their multiple benefits to health. The sparkling wine based beverage with elderflower syrup was produced by fermentation in the bottle (after Champenoise method, with the addition of wine yeast. The novelty brought by this paper is the use of elderflower syrup in alcoholic-beverage industry.

  4. Increasing the efficiency of sulphur dioxide in wine by using of saturated higher fatty acids

    Directory of Open Access Journals (Sweden)

    Petra Bábíková

    2012-01-01

    Full Text Available This work is aimed on stopping of alcoholic fermentation to leave residual sugar and the possibility of sulfur dioxide reduction in wine technology and storage. As a very good opportunity showed mixture of higher saturated fatty acids with a reduced dose of sulfur dioxide. Experiments have confirmed that the concentration of viable yeasts in 1 ml of wine for variants treated with a mixture of fatty acids is significantly lower than in variants treated with sulfur dioxide alone. Then was monitored the influence of fatty acids on stored wine with residual sugar. At this point a dramatically prolongation of interval to secondary fermentation (depreciation of wine in the bottle was confirmed. Finally, attention was paid to influence on the organoleptic characteristics of wine treated this way. In this case, it is possible to consider the recommended concentration of fatty acid below the threshold of susceptibility.

  5. Chemical and volatile composition of jujube wines fermented by Saccharomyces cerevisiae with and without pulp contact and protease treatment

    Directory of Open Access Journals (Sweden)

    Wenye ZHANG

    2016-01-01

    Full Text Available Abstract This study evaluated the chemical and volatile composition of jujube wines fermented with Saccharomyces cerevisiae A1.25 with and without pulp contact and protease treatment during fermentation. Yeast cell population, total reducing sugar and methanol contents had significant differences between nonextracted and extracted wine. The nonextracted wines had significantly higher concentrations of ethyl 9-hexadecenoate, ethyl palmitate and ethyl oleate than the extracted wines. Pulp contact also could enhance phenylethyl alcohol, furfuryl alcohol, ethyl palmitat and ethyl oleate. Furthermore, protease treatment can accelerate the release of fusel oils. The first principal component separated the wine from the extracted juice without protease from other samples based on the higher concentrations of medium-chain fatty acids and medium-chain ethyl esters. Sensory evaluation showed pulp contact and protease could improve the intensity and complexity of wine aroma due to the increase of the assimilable nitrogen.

  6. Genomic evolution of Saccharomyces cerevisiae under Chinese rice wine fermentation.

    Science.gov (United States)

    Li, Yudong; Zhang, Weiping; Zheng, Daoqiong; Zhou, Zhan; Yu, Wenwen; Zhang, Lei; Feng, Lifang; Liang, Xinle; Guan, Wenjun; Zhou, Jingwen; Chen, Jian; Lin, Zhenguo

    2014-09-10

    Rice wine fermentation represents a unique environment for the evolution of the budding yeast, Saccharomyces cerevisiae. To understand how the selection pressure shaped the yeast genome and gene regulation, we determined the genome sequence and transcriptome of a S. cerevisiae strain YHJ7 isolated from Chinese rice wine (Huangjiu), a popular traditional alcoholic beverage in China. By comparing the genome of YHJ7 to the lab strain S288c, a Japanese sake strain K7, and a Chinese industrial bioethanol strain YJSH1, we identified many genomic sequence and structural variations in YHJ7, which are mainly located in subtelomeric regions, suggesting that these regions play an important role in genomic evolution between strains. In addition, our comparative transcriptome analysis between YHJ7 and S288c revealed a set of differentially expressed genes, including those involved in glucose transport (e.g., HXT2, HXT7) and oxidoredutase activity (e.g., AAD10, ADH7). Interestingly, many of these genomic and transcriptional variations are directly or indirectly associated with the adaptation of YHJ7 strain to its specific niches. Our molecular evolution analysis suggested that Japanese sake strains (K7/UC5) were derived from Chinese rice wine strains (YHJ7) at least approximately 2,300 years ago, providing the first molecular evidence elucidating the origin of Japanese sake strains. Our results depict interesting insights regarding the evolution of yeast during rice wine fermentation, and provided a valuable resource for genetic engineering to improve industrial wine-making strains. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  7. New techniques for wine aging

    Directory of Open Access Journals (Sweden)

    m Hatice Kalkan Yıldırı

    2017-01-01

    Full Text Available The aging of wine requires a long time therefore it can cause loss of time and money. Therefore using of new techniques for wine aging shortens the length of aging time and wines may be placed on the market more quickly. Nowadays, gamma irradiation, ultrasonic waves, AC electric field and micro-oxygenation are the new techniques for wine aging. Gamma irradiation (after fermentation is accelerated physical maturation method. Gamma irradiation, in a suitable dosage (200 Gy, is a suitable method for improving some wine defects and producing a higher taste quality in wine. The 20 kHz ultrasonic waves aged wine much more quickly than standard aging, with similar quality. The wine treated by 20 kHz ultrasonic waves had a taste equivalent to 1 year aged wine. Wine maturing with AC electric field promises novel process accelerating aging process of fresh wine when suitable conditions are applied. As a result of research, an optimum treatment (electric field 600 V/cm and duration time 3 min was identified to accelerate wine aging. Harsh and pungent raw wine become harmonious and dainty. This process is equivalent to 6 month aging in oak barrel. Microoxygenation is a very important technique used in aging wines in order to improve their characteristics. The techniques of wine tank aging imply the use of small doses of oxygen (2 ml L−1 month−1 and the addition of wood pieces of oak to the wine. Studies concerning these new techniques demonstrated that maturation of wines become more quickly than standard maturation procedures with keeping and improving the wine quality.

  8. Design and performance testing of a DNA extraction assay for sensitive and reliable quantification of acetic acid bacteria directly in red wine using real time PCR

    Directory of Open Access Journals (Sweden)

    Cédric eLONGIN

    2016-06-01

    Full Text Available Although strategies exist to prevent AAB contamination, the increased interest for wines with low sulfite addition leads to greater AAB spoilage. Hence there is a real need for a rapid, specific, sensitive and reliable method for detecting these spoilage bacteria. All these requirements are met by real time Polymerase Chain Reaction (or quantitative PCR; qPCR. Here, we compare existing methods of isolating DNA and their adaptation to a red wine matrix. Two different protocols for isolating DNA and three PCR mix compositions were tested to select the best method. The addition of insoluble polyvinylpolypyrrolidone (PVPP at 1% (v/v during DNA extraction using a protocol succeeded in eliminating PCR inhibitors from red wine. We developed a bacterial internal control which was efficient in avoiding false negative results due to decreases in the efficiency of DNA isolation and/or amplification. The specificity, linearity, repeatability and reproducibility of the method were evaluated. A standard curve was established for the enumeration of AAB inoculated into red wines. The limit of quantification in red wine was 3.7 log AAB/mL and about 2.8 log AAB/mL when the volume of the samples was increased from 1 mL to 10 mL. Thus the DNA extraction method developed in this paper allows sensitive and reliable AAB quantification without underestimation thanks to the presence of an internal control. Moreover, monitoring of both the AAB population and the amount of acetic acid in ethanol medium and red wine highlighted that a minimum about 6.0 log cells/mL of AAB is needed to significantly increase the production of acetic acid leading to spoilage.

  9. Glycoproteomic profile in wine: a 'sweet' molecular renaissance

    DEFF Research Database (Denmark)

    Palmisano, Giuseppe; Antonacci, Donato; Larsen, Martin Røssel

    2010-01-01

    strategy in combination with tandem mass spectrometry was performed in order to analyze the glycoproteome of white wine. A total of 28 glycoproteins and 44 glycosylation sites were identified. The identified glycoproteins were from grape and yeast origin. In particular, several glycoproteins derived from...... grape, like invertase and pathogenesis-related (PR) proteins, and from the yeast, were found after the vinification process. Bioinformatic analysis revealed sequence similarity between the identified grape glycoproteins and known plant allergens. This study is an important step forward in order...

  10. Wine from the Netherlands: investigating the effect of soil-type on taste

    Science.gov (United States)

    Vis, Geert-Jan; Maljers, Denise; Beurskens, Stan

    2016-04-01

    During the last decade professional viticulture has seen a strong increase in the Netherlands, reaching 270 ha in 2015. Although on a European scale this is a small area, the number of prize-winning quality wines is steadily growing. This growth can largely be ascribed to new grape varieties from Germany and Switzerland, that are better adapted to the cooler and moister climate at the northern fringe of the viticultural zone, as well as to increasing viticultural expertise. The distribution of vineyards across the Netherlands shows that they occur on a plethora of substrates. Dutch substrate is dominated by typical lowland deposits such as fluvial and marine sands and clays and aeolian sands. Unlike many European countries, bedrock is scarce. Only in the south-eastern extremity and in the east of the country, carbonate bedrock is present at or near the surface. This wide variety of substrate triggered our interest in the effect of the various soil-types on the smell and taste characteristics of wines. An effect which is often mentioned concerning well-known foreign wines. We wondered whether an Auxerrois wine from carbonate rocks tastes significantly different from a wine from the same grape variety from loess. And how about a Johanniter wine from fluvial deposits versus windblown sands? And what happens if you make wine in exactly the same way with the same grape variety and from the same vineyard, but with three different yeast types? To answer our questions, we selected ten Dutch vineyards with varying soil-types and the grape varieties Auxerrois and Johanniter. In October 2014 we harvested the grapes and wine was made under controlled identical conditions (in a double setup). The wines were scientifically tested at the institute of Viticulture and Oenology in Neustadt, Germany. The results show no significant effect of soil-type on the smell and taste of Dutch wines in our experiment. Varying yeast types (Cryarome, 3079, VL2) used on Souvignier Gris grapes from

  11. 27 CFR 24.218 - Other wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Other wine. 24.218 Section... THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.218 Other wine. (a) General. Other than standard wine not included in other sections in this subpart are considered other wine. Those...

  12. 27 CFR 24.292 - Exported wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Exported wine. 24.292... OF THE TREASURY LIQUORS WINE Removal, Return and Receipt of Wine Removals Without Payment of Tax § 24.292 Exported wine. (a) General. Wine may be removed from a bonded wine premises without payment of tax...

  13. 27 CFR 4.27 - Vintage wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Vintage wine. 4.27 Section... THE TREASURY LIQUORS LABELING AND ADVERTISING OF WINE Standards of Identity for Wine § 4.27 Vintage wine. (a) General. Vintage wine is wine labeled with the year of harvest of the grapes and made in...

  14. Proteins involved in flor yeast carbon metabolism under biofilm formation conditions.

    Science.gov (United States)

    Moreno-García, Jaime; García-Martínez, Teresa; Moreno, Juan; Mauricio, Juan Carlos

    2015-04-01

    A lack of sugars during the production of biologically aged wines after fermentation of grape must causes flor yeasts to metabolize other carbon molecules formed during fermentation (ethanol and glycerol, mainly). In this work, a proteome analysis involving OFFGEL fractionation prior to LC/MS detection was used to elucidate the carbon metabolism of a flor yeast strain under biofilm formation conditions (BFC). The results were compared with those obtained under non-biofilm formation conditions (NBFC). Proteins associated to processes such as non-fermentable carbon uptake, the glyoxylate and TCA cycles, cellular respiration and inositol metabolism were detected at higher concentrations under BFC than under the reference conditions (NBFC). This study constitutes the first attempt at identifying the flor yeast proteins responsible for the peculiar sensory profile of biologically aged wines. A better metabolic knowledge of flor yeasts might facilitate the development of effective strategies for improved production of these special wines. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Wine and Climate Change

    OpenAIRE

    Ashenfelter, Orley; Storchmann, Karl

    2014-01-01

    In this article we provide an overview of the extensive literature on the impact of weather and climate on grapes and wine with the goal of describing how climate change is likely to affect their production. We start by discussing the physical impact of weather on vine phenology, berry composition and yields, and then survey the economic literature measuring the effects of temperature on wine quality, prices, costs and profits and how climate change will affect these. We also describe what ha...

  16. Wine tourism and sustainable environments

    Directory of Open Access Journals (Sweden)

    M.ª Luisa González San José

    2017-11-01

    Full Text Available Sustainability is a model of development in which the present actions should not compromise the future of future generations, and is linked to economic and social development which must respect the environment. Wine tourism or enotourism is a pleasant mode of tourism that combines the pleasure of wine-tasting, with cultural aspects related to the wine culture developing in wine regions over time until the present day. It can be affirmed that wine culture, and its use through wine tourism experiences, is clearly correlated to social (socially equitable, economic (economically feasible, environmental (environmentally sound and cultural aspects of the sustainability of winegrowing regions and territories.

  17. A new wine superpower? An analysis of the Chinese wine industry

    OpenAIRE

    Li, Yuanbo; Bardaji de Azcarate, Isabel

    2017-01-01

    China is one of the most attractive wine markets and a hopeful wine producer in the twenty-first century. Current studies of wine in China tend to focus on the wine market but seldom analyze the domestic wine industry, which contributes approximately 70% of the total wine consumed in the country. This paper reviews the wine history and the development of wine in China and analyses the current situation and perspectives of the Chinese wine industry, considering both traditional con...

  18. ASPECTS REGARDING WINE PRODUCTION AND WINE SECTOR COMPETITIVENESS IN ROMANIA

    Directory of Open Access Journals (Sweden)

    Raluca Georgiana LADARU

    2014-10-01

    Full Text Available The paper aimed to make some assumptions regarding wine sector competitiveness in Romania. Vineyards have an important share in Romanian agriculture, Romania being ranked on 11th position in the world and on 5th position in the European Union in terms of vineyards surface, while the wine industry is an important contributor to the GDP. The research method was based on analyze of wine sector evolution in the last years. The paper presents current global context of wine market at international level and focus on Romanian wine production sector and wine trade, seen in the light of competitiveness. The competitiveness of Romanian wine sector need to be related with measures that are able to increase the attractiveness of Romanian wines, both on domestic and external markets.

  19. Influence of Production Method on the Chemical Composition, Foaming Properties, and Quality of Australian Carbonated and Sparkling White Wines.

    Science.gov (United States)

    Culbert, Julie A; McRae, Jacqui M; Condé, Bruna C; Schmidtke, Leigh M; Nicholson, Emily L; Smith, Paul A; Howell, Kate S; Boss, Paul K; Wilkinson, Kerry L

    2017-02-22

    The chemical composition (protein, polysaccharide, amino acid, and fatty acid/ethyl ester content), foaming properties, and quality of 50 Australian sparkling white wines, representing the four key production methods, that is, Méthode Traditionelle (n = 20), transfer (n = 10), Charmat (n = 10), and carbonation (n = 10), were studied. Méthode Traditionelle wines were typically rated highest in quality and were higher in alcohol and protein contents, but lower in residual sugar and total phenolics, than other sparkling wines. They also exhibited higher foam volume and stability, which might be attributable to higher protein concentrations. Bottle-fermented Méthode Traditionelle and transfer wines contained greater proportions of yeast-derived mannoproteins, whereas Charmat and carbonated wines were higher in grape-derived rhamnogalacturonans; however, total polysaccharide concentrations were not significantly different between sparkling wine styles. Free amino acids were most abundant in carbonated wines, which likely reflects production via primary fermentation only and/or the inclusion of nontraditional grape varieties. Fatty acids and their esters were not correlated with foaming properties, but octanoic and decanoic acids and their ethyl esters were present in Charmat and carbonated wines at significantly higher concentrations than in bottle-fermented wines and were negatively correlated with quality ratings. Research findings provide industry with a better understanding of the compositional factors driving the style and quality of sparkling white wine.

  20. Wine and Maths: Mathematical Solutions to Wine-Inspired Problems

    Science.gov (United States)

    Cadeddu, L.; Cauli, A.

    2018-01-01

    We deal with an application of partial differential equations to the correct definition of a wine cellar. We present some historical details about this problem. We also discuss how to build or renew a wine cellar, creating ideal conditions for the ageing process and improving the quality of wines. Our goal is to calculate the optimal depth…

  1. Is wine savory? Umami taste in wine

    OpenAIRE

    Alice, Vilela; António, Inês; Fernanda, Cosme

    2016-01-01

    Umami is an important taste element in natural products like wine. The umami taste has distinctive properties that differentiate it from other tastes, including a taste-enhancing synergism between two umami compounds, L-glutamate and 5’-ribonulceotides, and a prolonged aftertaste. In human taste cells, taste buds transduce the chemicals that elicit the umami tastes into membrane depolarization, which triggers release of transmitter to activate gustatory afferent nerve fibers. Umami taste stim...

  2. Predicting and preventing mold spoilage of food products.

    Science.gov (United States)

    Dagnas, Stéphane; Membré, Jeanne-Marie

    2013-03-01

    This article is a review of how to quantify mold spoilage and consequently shelf life of a food product. Mold spoilage results from having a product contaminated with fungal spores that germinate and form a visible mycelium before the end of the shelf life. The spoilage can be then expressed as the combination of the probability of having a product contaminated and the probability of mold growth (germination and proliferation) up to a visible mycelium before the end of the shelf life. For products packed before being distributed to the retailers, the probability of having a product contaminated is a function of factors strictly linked to the factory design, process, and environment. The in-factory fungal contamination of a product might be controlled by good manufacturing hygiene practices and reduced by particular processing practices such as an adequate air-renewal system. To determine the probability of mold growth, both germination and mycelium proliferation can be mathematically described by primary models. When mold contamination on the product is scarce, the spores are spread on the product and more than a few spores are unlikely to be found at the same spot. In such a case, models applicable for a single spore should be used. Secondary models can be used to describe the effect of intrinsic and extrinsic factors on either the germination or proliferation of molds. Several polynomial models and gamma-type models quantifying the effect of water activity and temperature on mold growth are available. To a lesser extent, the effect of pH, ethanol, heat treatment, addition of preservatives, and modified atmospheres on mold growth also have been quantified. However, mold species variability has not yet been properly addressed, and only a few secondary models have been validated for food products. Once the probability of having mold spoilage is calculated for various shelf lives and product formulations, the model can be implemented as part of a risk management

  3. Consumer perceptions of organic wine

    Directory of Open Access Journals (Sweden)

    Anca IORDACHESCU

    2010-08-01

    Full Text Available The paper develops a study on the Romanians’ attitudes towards the organic wines. The analysis has been done in two stages – at a quantitative level and a qualitative one. The quantitative study has been done on a sample of 122 respondents – consumers and non-consumersin low percentage. The questionnaire investigated the general perception of wines, and included a dedicated section for the organic wines, addressed to the respondents aware of this product.The qualitative stage has been realized through a sensorial analysis, where three white wines and two red wines have been tasted by trained tasters. Among the five wines, one white – Chardonnay was organicwine. Both studies proved that the organic wine has a potential in Romania due to the sensorial qualities and people’s perception. However, the development of organic wine market won’t be a quick process and it will require first of all improving Romanians’ ‘organic’ culture.

  4. Optimizing the Operation of Maceration to Obtain Quality White Wines

    Directory of Open Access Journals (Sweden)

    Stegărus Diana

    2014-06-01

    Full Text Available This study monitors the physico-chemical properties of wines from Dragasani under the influence of pectolytic enzymes in various temperature conditions. during maceration contact is made between the grape skins and selected the optimal time leads to wines with more pronounced floral character. The physico-chemical extraction maceration leads to a more pronounced specific compounds, the time of maceration is very important in this case. The curing time is of great importance in producing varieties Muscat Ottonel and Tămâioasă Românească primarily for successful extraction of aromatic components from grape. As noted in the literature flavored grapes contain large amounts of terpene compounds are in free form or bound. To optimize the technological process is able to extract these compounds and to achieve a harmonious and balanced wine. The variants considered in the study presents the results of physico-chemical and aromatic wines obtained from the Muscat Ottonel and Tămâioasă Românească, which took into consideration both during maceration and the use of selected yeasts and enzymes, which form the basis for the selection of the optimal procedure for obtaining aromatic white wines in Dragasani Vineyard.

  5. MALDI-TOF MS as a tool to identify foodborne yeasts and yeast-like fungi.

    Science.gov (United States)

    Quintilla, Raquel; Kolecka, Anna; Casaregola, Serge; Daniel, Heide M; Houbraken, Jos; Kostrzewa, Markus; Boekhout, Teun; Groenewald, Marizeth

    2018-02-02

    Since food spoilage by yeasts causes high economic losses, fast and accurate identifications of yeasts associated with food and food-related products are important for the food industry. In this study the efficiency of the matrix assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) to identify food related yeasts was evaluated. A CBS in-house MALDI-TOF MS database was created and later challenged with a blinded test set of 146 yeast strains obtained from food and food related products. Ninety eight percent of the strains were correctly identified with log score values>1.7. One strain, Mrakia frigida, gained a correct identification with a score value1.7. Ambiguous identifications were observed due to two incorrect reference mass spectra's found in the commercial database BDAL v.4.0, namely Candida sake DSM 70763 which was re-identified as Candida oleophila, and Candida inconspicua DSM 70631 which was re-identified as Pichia membranifaciens. MALDI-TOF MS can distinguish between most of the species, but for some species complexes, such as the Kazachstania telluris and Mrakia frigida complexes, MALDI-TOF MS showed limited resolution and identification of sibling species was sometimes problematic. Despite this, we showed that the MALDI-TOF MS is applicable for routine identification and validation of foodborne yeasts, but a further update of the commercial reference databases is needed. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Technological change in the wine market? The role of QR codes and wine apps in consumer wine purchases

    OpenAIRE

    Lindsey M. Higgins; Marianne McGarry Wolf; Mitchell J. Wolf

    2014-01-01

    As an experiential good, wine purchases in the absence of tastings are often challenging and information-laden decisions. Technology has shaped the way consumers negotiate this complex purchase process. Using a sample of 631 US wine consumers, this research aims to identify the role of mobile applications and QR codes in the wine purchase decision. Results suggest that wine consumers that consider themselves wine connoisseurs or experts, enjoy talking about wine, and are interested in wine th...

  7. Fun with Singing Wine Glasses

    Science.gov (United States)

    Boone, Christine; Galloway, Melodie; Ruiz, Michael J.

    2018-01-01

    A fun activity is presented using singing wine glasses for introductory physics students. Students tune a white wine glass and a red wine glass to as many semitones as possible by filling the glasses with the appropriate amounts of water. A smart phone app is used to measure the frequencies of equal-temperament tones. Then plots of frequency…

  8. Prevention of fungal spoilage in food products using natural compounds: A review.

    Science.gov (United States)

    Ribes, Susana; Fuentes, Ana; Talens, Pau; Barat, Jose Manuel

    2017-04-10

    The kingdom Fungi is the most important group of microorganism contaminating food commodities, and chemical additives are commonly used in the food industry to prevent fungal spoilage. However, the increasing consumer concern about synthetic additives has led to their substitution by natural compounds in foods. The current review provides an overview of using natural agents isolated from different sources (plants, animals, and microorganisms) as promising antifungal compounds, including information about their mechanism of action and their use in foods to preserve and prolong shelf life. Compounds derived from plants, chitosan, lactoferrin, and biocontrol agents (lactic acid bacteria, antagonistic yeast, and their metabolites) are able to control the decay caused by fungi in a wide variety of foods. Several strategies are employed to reduce the drawbacks of some antifungal agents, like their incorporation into oil-in-water emulsions and nanoemulsions, edible films and active packaging, and their combination with other natural preservatives. These strategies facilitate the addition of volatile agents into food products and, improve their antifungal effectiveness. Moreover, biological agents have been investigated as one of the most promising options in the control of postharvest decay. Numerous mechanisms of action have been elucidated and different approaches have been studied to enhance their antifungal effectiveness.

  9. Electronic Nose For Measuring Wine Evolution In Wine Cellars

    International Nuclear Information System (INIS)

    Lozano, J.; Santos, J. P.; Horrillo, M. C.; Cabellos, J. M.; Arroyo, T.

    2009-01-01

    An electronic nose installed in a wine cellar for measuring the wine evolution is presented in this paper. The system extract the aroma directly from the tanks where wine is stored and carry the volatile compounds to the sensors cell. A tin oxide multisensor, prepared with RF sputtering onto an alumina substrate and doped with chromium and indium, is used. The whole system is fully automated and controlled by computer and can be supervised by internet. Linear techniques like principal component analysis (PCA) and nonlinear ones like probabilistic neural networks (PNN) are used for pattern recognition. Results show that system can detect the evolution of two different wines along 9 months stored in tanks. This system could be trained to detect off-odours of wine and warn the wine expert to correct it as soon as possible, improving the final quality of wine.

  10. [Eulogy of wine?].

    Science.gov (United States)

    Godfroid, I O

    1997-12-20

    In the literature the beneficial effects on health of drinking alcoholic beverages, especially red wine, is becoming increasingly more evident. We report an objective analysis of the advantages and the dangers of such a tendency. It appears that the daily consumption of red wine at moderate doses (200-400 ml a day) has real prophylactic effects. These are particularly marked in the prevention of coronary heart disease (CHD), but also for a possible cancer chemopreventive activity, in the prevention of type II diabetes, of ischemic stroke, of osteoporosis in older women, and of Alzheimer's disease. But, inasmuch as the consumption of alcoholic beverages always involves a potential danger (organic diseases, risk of dependence, alcoholism), from a medical point of view eulogy to wine is ethically indefensible. Similar effects may be obtained from a diet rich in fruits and fresh vegetables.

  11. Augmentation of chemical and organoleptic properties in Syzygium cumini wine by incorporation of grape seeds during vinification.

    Science.gov (United States)

    VenuGopal, K S; Cherita, Chris; Anu-Appaiah, K A

    2018-03-01

    The role of grape seed tannins on improving organoleptic properties and its involvement in color stabilization in red wine are well established. The addition of grape seeds as the source of condensed tannins in fruit wine may provide a solution for its color instability and improvement of sensory attributes. Syzgium cumini is traditionally known for its therapeutic properties. In the current study, the influence of yeasts and grape seed addition during fermentation on the chromatic, phenolic and sensory attributes of the wine was accessed. Grape seed addition improved the color characteristics of wine and increased overall phenolic composition. Analysis by HPLC revealed 6 major anthocyanins, among which 3, 5-diglucoside form of delphidin and petunidin was found to be the major components. Cluster and PLSR analysis explained the impact of seed addition on the yeasts, as well as on the perception of panelists, with bitterness and astringency as the dominating attributes. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Relationship between Menthiafolic Acid and Wine Lactone in Wine.

    Science.gov (United States)

    Giaccio, Joanne; Curtin, Chris D; Sefton, Mark A; Taylor, Dennis K

    2015-09-23

    Menthiafolic acid (6-hydroxy-2,6-dimethylocta-2,7-dienoic acid, 2a) was quantified by GC-MS in 28 white wines, 4 Shiraz wines, and for the first time in 6 white grape juice samples. Menthiafolic acid was detected in all but one of the wine samples at concentrations ranging from 26 to 342 μg/L and in the juice samples from 16 to 236 μg/L. Various model fermentation experiments showed that some menthiafolic acid in wine could be generated from the grape-derived menthiafolic acid glucose ester (2b) during alcoholic and malolactic fermentation. Samples containing high concentrations of menthiafolic acid were also analyzed by enantioselective GC-MS and were shown to contain this compound in predominantly the (S)-configuration. Enantioselective analysis of wine lactone (1) in one of these samples, a four-year-old Chardonnay wine showed, for the first time, the presence of the 3R,3aR,7aS isomer of wine lactone (1b), which is the enantiomer of the form previously reported as the sole isomer present in young wine samples. The weakly odorous 3R,3aR,7aS 1b form comprised 69% of the total wine lactone in the sample. On the basis of the enantioselectivity of the hydrolytic conversion of menthiafolic acid to wine lactone at pH 3.0 determined previously and the relative proportions of (R)- and (S)-menthiafolic acid in the Chardonnay wine, the predicted ratio of wine lactone enantiomers that would be formed from hydrolysis at ambient temperature of the menthiafolic acid present in this wine was close to the ratio measured, which was consistent with menthiafolic acid being the major or sole precursor to wine lactone in this sample.

  13. Novel brewing yeast hybrids: creation and application.

    Science.gov (United States)

    Krogerus, Kristoffer; Magalhães, Frederico; Vidgren, Virve; Gibson, Brian

    2017-01-01

    The natural interspecies Saccharomyces cerevisiae × Saccharomyces eubayanus hybrid yeast is responsible for global lager beer production and is one of the most important industrial microorganisms. Its success in the lager brewing environment is due to a combination of traits not commonly found in pure yeast species, principally low-temperature tolerance, and maltotriose utilization. Parental transgression is typical of hybrid organisms and has been exploited previously for, e.g., the production of wine yeast with beneficial properties. The parental strain S. eubayanus has only been discovered recently and newly created lager yeast strains have not yet been applied industrially. A number of reports attest to the feasibility of this approach and artificially created hybrids are likely to have a significant impact on the future of lager brewing. De novo S. cerevisiae × S. eubayanus hybrids outperform their parent strains in a number of respects, including, but not restricted to, fermentation rate, sugar utilization, stress tolerance, and aroma formation. Hybrid genome function and stability, as well as different techniques for generating hybrids and their relative merits are discussed. Hybridization not only offers the possibility of generating novel non-GM brewing yeast strains with unique properties, but is expected to aid in unraveling the complex evolutionary history of industrial lager yeast.

  14. Study of the role of the covalently linked cell wall protein (Ccw14p) and yeast glycoprotein (Ygp1p) within biofilm formation in a flor yeast strain.

    Science.gov (United States)

    Moreno-García, J; Coi, A L; Zara, G; García-Martínez, T; Mauricio, J C; Budroni, M

    2018-03-01

    Flor yeasts are Saccharomyces cerevisiae strains noted by their ability to create a type of biofilm in the air-liquid interface of some wines, known as 'flor' or 'velum', for which certain proteins play an essential role. Following a proteomic study of a flor yeast strain, we deleted the CCW14 (covalently linked cell wall protein) and YGP1 (yeast glycoprotein) genes-codifying for two cell surface glycoproteins-in a haploid flor yeast strain and we reported that both influence the weight of the biofilm as well as cell adherence (CCW14).

  15. Yeast diversity and native vigor for flavor phenotypes.

    Science.gov (United States)

    Carrau, Francisco; Gaggero, Carina; Aguilar, Pablo S

    2015-03-01

    Saccharomyces cerevisiae, the yeast used widely for beer, bread, cider, and wine production, is the most resourceful eukaryotic model used for genetic engineering. A typical concern about using engineered yeasts for food production might be negative consumer perception of genetically modified organisms. However, we believe the true pitfall of using genetically modified yeasts is their limited capacity to either refine or improve the sensory properties of fermented foods under real production conditions. Alternatively, yeast diversity screening to improve the aroma and flavors could offer groundbreaking opportunities in food biotechnology. We propose a 'Yeast Flavor Diversity Screening' strategy which integrates knowledge from sensory analysis and natural whole-genome evolution with information about flavor metabolic networks and their regulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Botrytized wines – current perspectives

    Directory of Open Access Journals (Sweden)

    Magyar I

    2016-10-01

    Full Text Available Ildikó Magyar, János Soós Department of Oenology, Institute of Viticulture and Oenology, Szent István University, Budapest, Hungary Abstract: Botrytized wines are wine specialties made of overripe grapes infected by Botrytis cinerea with the form “noble rot”. Due to the particular characteristics of the noble rotted grape, these wines (eg, Tokaji Aszú, Sauternes, Trockenbeerenauslese types, etc have many characteristic features, including higher or lower residual sugar content and unique aroma composition. The technology, biochemistry, and special characteristics of botrytized wines have been researched for a long time. This review outlines the main directions of the current studies, giving a brief overview on the recent findings. Beside the traditional wine types, noble rot is increasingly utilized in making newer sweet wine styles and straw (passito wines, which generates a series of new interesting experimental results. The fungus–grape interactions during the noble rot, the induced botrytization, the microbial communities of botrytized wines, and the volatile compounds having key roles in the distinct aroma of these wine styles are being focused on in the current studies in this field. Keywords: Botrytis, noble rot, sweet wines, passito wine, aroma

  17. Influence of ethanol and temperature on the cellular fatty acid composition of Zygosaccharomyces bailii spoilage yeasts

    NARCIS (Netherlands)

    Baleiras Couto, M.M.; Huis in 't Veld, J.H.J.

    1995-01-01

    Changes in the fatty acid profile of Zygosaccharomyces bailii strains, isolated from different sources, after growth at increasing concentrations of ethanol and/or decreasing temperatures were determined. Differences in fatty acid composition between Zygosaccharomyces bailii strains at standard

  18. 27 CFR 24.203 - Honey wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Honey wine. 24.203 Section... THE TREASURY LIQUORS WINE Production of Agricultural Wine § 24.203 Honey wine. (a) Subject to paragraph (b) of this section, a winemaker, in the production of wine from honey, may add the following: (1...

  19. Determination of Favorite Wine from Comparison of Wine Aroma Attributes

    Science.gov (United States)

    Koike, Takayuki; Kamimura, Hironobu; Shimada, Kouji; Yamada, Hiroshi; Kaneki, Noriaki

    The decision to choose the appropriate product matching the preference of each individual is based on the psychological impression of the adjective and the alternatives. The preference for a product group and physical condition also affect decision-making. The purpose of this study was to investigate the influence of differences in the preference of wine and changes in hunger level on the psychological and neuro-physiological aspects of decision-making where the subjects were asked to choose their most favorite wine after sniffing the aroma of several wines. The psychological aspects of decision-making while sniffing five different kinds of wine were evaluated by the analytical hierarchal process (AHP) method, while the neuro-physiological aspects were evaluated by measuring the level of oxygenated hemoglobin concentrations (O2Hb) in the process of smelling the wine aromas within three minutes compared to when the non-odor and alcoholic solutions were presented. AHP analysis showed that the adjective “Favorite” was given the highest importance and a white wine with a sweet aroma was the most favored wine, regardless of the wine preference. The normalized mean O2Hb levels in each minute showed that, in the case of the wine lovers, the time course of the O2Hb level, decreased when they sensed the wine aroma compared to when they sensed non-odor solutions, and, in non-wine lovers, the O2Hb levels remained at higher values compared to the smell of the non-odor solution when they sensed the aroma of the alcoholic solution. The results indicate that there are differences with regard to decision-making between the psychological and physiological aspects when people are made to choose their most favorite wine by sniffing wine aromas.

  20. A combined meta-barcoding and shotgun metagenomic analysis of spontaneous wine fermentation.

    Science.gov (United States)

    Sternes, Peter R; Lee, Danna; Kutyna, Dariusz R; Borneman, Anthony R

    2017-07-01

    Wine is a complex beverage, comprising hundreds of metabolites produced through the action of yeasts and bacteria in fermenting grape must. Commercially, there is now a growing trend away from using wine yeast (Saccharomyces) starter cultures, toward the historic practice of uninoculated or "wild" fermentation, where the yeasts and bacteria associated with the grapes and/or winery perform the fermentation. It is the varied metabolic contributions of these numerous non-Saccharomyces species that are thought to impart complexity and desirable taste and aroma attributes to wild ferments in comparison to their inoculated counterparts. To map the microflora of spontaneous fermentation, metagenomic techniques were employed to characterize and monitor the progression of fungal species in 5 different wild fermentations. Both amplicon-based ribosomal DNA internal transcribed spacer (ITS) phylotyping and shotgun metagenomics were used to assess community structure across different stages of fermentation. While providing a sensitive and highly accurate means of characterizing the wine microbiome, the shotgun metagenomic data also uncovered a significant overabundance bias in the ITS phylotyping abundance estimations for the common non-Saccharomyces wine yeast genus Metschnikowia. By identifying biases such as that observed for Metschnikowia, abundance measurements from future ITS phylotyping datasets can be corrected to provide more accurate species representation. Ultimately, as more shotgun metagenomic and single-strain de novo assemblies for key wine species become available, the accuracy of both ITS-amplicon and shotgun studies will greatly increase, providing a powerful methodology for deciphering the influence of the microbial community on the wine flavor and aroma. © The Authors 2017. Published by Oxford University Press.

  1. Application of ultrasound to improve lees ageing processes in red wines.

    Science.gov (United States)

    Del Fresno, Juan Manuel; Loira, Iris; Morata, Antonio; González, Carmen; Suárez-Lepe, Jose Antonio; Cuerda, Rafael

    2018-09-30

    Ageing on lees (AOL) is a technique that increases volatile compounds, promotes colour stability, improves mouthfeel and reduces astringency in red wines. The main drawback is that it is a slow process. Several months are necessary to obtain perceptible effects in wines. Different authors have studied the application of new techniques to accelerate the AOL process. Ultrasound (US) has been used to improve different food industry processes; it could be interesting to accelerate the yeast autolysis during AOL. This work evaluates the use of the US technique together with AOL and oak chips for this purpose studying the effects of different oenological parameters of red wines. The results obtained indicate an increase of polysaccharides content when US is applied in wine AOL. In addition, total polyphenol index (TPI) and volatile acidity were not affected. However, this treatment increases the dissolved oxygen affecting the volatile compounds and total anthocyanins. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Evaluation of organic and inorganic compounds levels of red wines processed from Pinot Noir grapes

    Directory of Open Access Journals (Sweden)

    Heli Sirén

    2015-03-01

    The wine products showed different profiles of carbohydrates, organic acids, phenolic compounds, and minerals. Especially, saccharose (max. 0.21 g/L, rhamnose (max. 0.45 g/L, fructose (max. 1.9 g/L, and phosphate (max 1.4 g/L quantities were extremely high in some wines. The results also showed that yeast fermentation in winemaking agitated high production of lactic (max 5.7 g/L and tartaric (max 1.7 g/L acids. The red wines processed by cold maceration and natural fermentation gave similar profiles. Only one of the Pinot Noir wines entirely differentiated from the others with comparison of carbohydrates and organic acids.

  3. Use of simulated annealing in standardization and optimization of the acerola wine production

    Directory of Open Access Journals (Sweden)

    Sheyla dos Santos Almeida

    2014-06-01

    Full Text Available In this study, seven wine samples were prepared varying the amount of pulp of acerola fruits and the sugar content using the simulated annealing technique to obtain the optimal sensory qualities and cost for the wine produced. S. cerevisiae yeast was used in the fermentation process and the sensory attributes were evaluated using a hedonic scale. Acerola wines were classified as sweet, with 11°GL of alcohol concentration and with aroma, taste, and color characteristics of the acerola fruit. The simulated annealing experiments showed that the best conditions were found at mass ratio between 1/7.5-1/6 and total soluble solids between 28.6-29.0 °Brix, from which the sensory acceptance scores of 6.9, 6.8, and 8.8 were obtained for color, aroma, and flavor, respectively, with a production cost 43-45% lower than the cost of traditional wines commercialized in Brazil.

  4. Port-wine stain

    Science.gov (United States)

    ... About MedlinePlus Show Search Search MedlinePlus GO GO About MedlinePlus Site Map FAQs Customer Support Health Topics Drugs & Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Port-wine stain URL of this page: //medlineplus.gov/ency/ ...

  5. Does wine prevent dementia?

    Directory of Open Access Journals (Sweden)

    Roger M Pinder

    2009-02-01

    Full Text Available Roger M PinderPharma Consultant, York, UKAbstract: There is substantial evidence that moderate consumption of alcohol reduces significantly the risks of coronary heart disease, stroke and type 2 diabetes. Furthermore, the incidence of dementia, both of the Alzheimer’s type (AD and the vascular variety (VaD, is lower in societies which consume a Mediterranean diet of mainly fish, fruit, vegetables, olive oil, and wine. In particular, extensive evidence from both population-based cohort and case control studies in different areas of the world and across genders and racial groups suggests that regular consumption of moderate amounts of alcohol, especially in the form of wine, is associated with a lower risk of developing AD and VaD compared with abstention and heavy drinking. Carriers of the APOE ε4 allele seem to gain less benefit. Age-related cognitive decline, particularly in women, is lower in regular drinkers, while older drinkers with Mild Cognitive Impairment (MCI progress less frequently to AD than their abstaining counterparts. Plausible biological mechanisms for the neuroprotective effects of wine include its glucose-modifying, antioxidant and inflammatory properties, but it additionally seems to modify the neuropathology of AD, particularly the deposition of amyloid plaque. Indeed, some of these mechanisms are already targets for the development of new therapeutic agents for the treatment of dementia.Keywords: alcohol, Alzheimer’s disease, dementia, epidemiology, polyphenols, wine

  6. Comparison of the yeast microbiota of different varieties of cool-climate grapes by PCR-RAPD

    Directory of Open Access Journals (Sweden)

    Iwona Drożdż

    2015-08-01

    Full Text Available The yeast microbiota occurring on different varieties of grapes grown in cool-climate is not completely researched. Therefore, its identification is important to research. On the other hand, yeasts occurring in these fruits can be potentially used as starter cultures to obtain particularly demanded features in the production of wine. In addition, rapid methods for yeast identification allow to eliminate the contamination with pathogenic yeasts, which could cause the loss of wine production. The aim of the study was to isolate and identify the yeasts occurring on the surface of the different varieties of white and red grapes, grown in cool-climate of Poland. Also, the aim was to compare the qualitative and quantitative composition of yeasts on the tested grapes. The 84 cultures of yeasts were isolated, that were initially macroscopic and microscopic analyzed and the purity of cultures was rated on the WL medium. Identification of yeasts by PCR-RAPD was carried using the M13 primer. In the PCR-RFLP method ITS1 and ITS4 primers, as well as restriction enzymes HhaI, HinfI, HaeIII, were used. Preliminary identification of yeasts by standard methods produced results very different from the results obtained by molecular methods. Among the isolated microorganisms yeasts were dominating, but bacteria and molds were also present. Using the PCR-RAPD method most strains of yeasts were identified. Yeast microflora of different varieties of white and red grapes was very similar as the same species of yeasts were identified. Yeasts of the genus Saccharomyces were present in all varieties of grapes. The Rhodotorula mucilaginosa, Saccharomyces cerevisiae, Metschnikowia pulcherrima, Rhodotorula minuta, Pichia kluyveri, Hanseniaspora uvarum and Rhodotorula mucilaginosa were identified by PCR-RAPD. 4 of the 33 tested strains of yeasts were identified by PCR-RFLP. By PCR-RAPD only Hanseniaspora uvarum was identified. The quantity and quality of microorganisms living

  7. Functional improvement of Saccharomyces cerevisiae to reduce volatile acidity in wine.

    Science.gov (United States)

    Luo, Zongli; Walkey, Christopher J; Madilao, Lufiani L; Measday, Vivien; Van Vuuren, Hennie J J

    2013-08-01

    Control of volatile acidity (VA) is a major issue for wine quality. In this study, we investigated the production of VA by a deletion mutant of the fermentation stress response gene AAF1 in the budding yeast Saccharomyces cerevisiae. Fermentations were carried out in commercial Chardonnay grape must to mimic industrial wine-making conditions. We demonstrated that a wine yeast strain deleted for AAF1 reduced acetic acid levels in wine by up to 39.2% without increasing the acetaldehyde levels, revealing a potential for industrial application. Deletion of the cytosolic aldehyde dehydrogenase gene ALD6 also reduced acetic acid levels dramatically, but increased the acetaldehyde levels by 41.4%, which is not desired by the wine industry. By comparison, ALD4 and the AAF1 paralog RSF2 had no effects on acetic acid production in wine. Deletion of AAF1 was detrimental to the growth of ald6Δ and ald4Δald6Δ mutants, but had no effect on acetic acid production. Overexpression of AAF1 dramatically increased acetic acid levels in wine in an Ald6p-dependent manner, indicating that Aaf1p regulates acetic acid production mainly via Ald6p. Overexpression of AAF1 in an ald4Δald6Δ strain produced significantly more acetic acid in wine than the ald4Δald6Δ mutant, suggesting that Aaf1p may also regulate acetic acid synthesis independently of Ald4p and Ald6p. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  8. Determination of metals content from wines by inductively coupled plasma mass spectrometry

    International Nuclear Information System (INIS)

    Iordache, Andreea-Maria; Geana, Elisabeta-Irina

    2009-01-01

    Full text: Wine is a widely consumed beverage with thousands of years of tradition. Wine composition strongly determines its quality besides having a great relevance on wine characterization, tipyfication and frauds detection. Wine composition is influenced by many and diverse factors corresponding to the specific production area, such as grape variety, soil and climate, culture, yeast, winemaking practices, transport and storage. Daily consumption of wine in moderate quantities contributes significantly to the requirements of the human organism for essential elements such as Cr, Cu, Zn, Fe, Mn, Co, Ni and Sr. On the other hand, several metals, such as Pb and Cd , are known to be potentially toxic. The objective of this work was to develop a method to determine the metals content in wine samples from Romania. Three samples of difference white wines available in the supermarket was analyzed for identify the presence of: Cr, Cu, Zn, Fe, Mn, Pb, Cd, Co, Ni and Sr by inductively coupled plasma mass spectrometry (ICP-MS). (authors)

  9. RESEARCHES CONCERNING THE EVOLUTION OF WINE MICROBIOTA DURING THE SPONTANEOUS FERMENTATION OF RED GRAPES JUICES

    Directory of Open Access Journals (Sweden)

    Ionica Deliu

    2010-01-01

    Full Text Available In order to keep its place on the wine international market, Romania should produce typical wines starting from localgrape varieties and conducting the alcoholic fermentation by starter cultures obtained from local isolated wine yeast.The present study was initiated due to the fact that there are few informations regarding the evolution of winemicrorganisms in plantations and in the fermentations process for quantitative point of view.The population dynamics of microbiota in Valea Calugareasca vineyard was analysed during the alcoholicfermentation. No yeast starter cultures had been used in order to investigate the dynamics of grape-related indigenousmicroorganisms population. Classical works and methods for alcoholic fermentation monitoring have been employed atthis level.At the beginning of fermentation the total number of yeasts found is doubling, while the number of bacteria is stabilizedat a value of 103 CFU/ml. During the alcoholic fermentation the yeasts become predominant (107–108 cfu/ml andcontinue the fermentation until its completion. Significant differences regarding the evolution of yeast microbiota forquantitative point of view between varieties have been recorded.

  10. Scavenging Capacities of Some Wines and Wine Phenolic Extracts

    Directory of Open Access Journals (Sweden)

    Ioannis G. Roussis

    2005-01-01

    Full Text Available The aim of this study was to assess the ability of different wines – a sweet red, a dry red, a sweet white, and a dry white – to scavenge the stable 1,1’-diphenyl-2-picryl-hydrazyl radical (DPPH. and to determine their phenolic composition. Both red wines contained, apart from anthocyanins, also higher concentration of total phenolics, tartaric esters, and flavonols than the two white wines. All wines exhibited scavenging activity analogous to their total phenolic content. However, their phenolics differed in antiradical potency, which was visible in their EC50 values. The dry red wine, Xinomavro, had a lower EC50 value, indicating the higher antiradical potency of its phenolics. The scavenging capacities of phenolic extracts from Xinomavro red wine on hydroxyl radicals, superoxide radicals, and singlet oxygen were also assessed. Wine total extract was fractionated by extraction, and each of the three fractions was then subfractionated by column chromatography into two subfractions. Wine total extract, and its fractions and subfractions exhibited scavenging capacity on hydroxyl radicals, superoxide radicals, and singlet oxygen, indicating the activity of many wine phenolics. The most active wine extracts towards hydroxyl radicals were characterized by the high peaks of flavanols, anthocyanins and flavonols in their HPLC-DAD chromatograms. The most active extract towards superoxide radicals was rich in flavanols and anthocyanins. The characteristic phenolics of the most active wine extracts towards singlet oxygen were flavanols, flavonols and phenolic acids. The ability of all red wine phenolic extracts to scavenge singlet oxygen, along with hydroxyl and superoxide radicals, emphasizes its health functionality.

  11. Effect of sequential fermentations and grape cultivars on volatile compounds and sensory profiles of Danish wines

    DEFF Research Database (Denmark)

    Liu, Jing; Arneborg, Nils; Toldam-Andersen, Torben

    2017-01-01

    BACKGROUND: There has been an increasing interest in the use of selected non-Saccharomyces yeasts in co-culture with Saccharomyces cerevisiae. In this work, three non-Saccharomyces yeast strains (Metschnikowia viticola, Metschnikowia fructicola and Hanseniaspora uvarum) indigenously isolated...... in Denmark were used in sequential fermentations with S. cerevisiae on three cool-climate grape cultivars, Bolero, Rondo and Regent. During the fermentations, the yeast growth was determined as well as key oenological parameters, volatile compounds and sensory properties of finished rosé wines. RESULTS......: The different non-Saccharomyces strains and cool-climate grape cultivars produced wines with a distinctive aromatic profile. A total of 67 volatile compounds were identified, including 43 esters, 14 alcohols, five acids, two ketones, a C13-norisoprenoid, a lactone and a sulfur compound. The use of M. viticola...

  12. Genetic relationship and biological status of the industrially important yeast Saccharomyces eubayanus Sampaio et al.

    Science.gov (United States)

    Naumov, G I

    2017-03-01

    The genomes of the recently discovered yeast Saccharomyces eubayanus and traditional S. cerevisiae are known to be found in the yeast S. pastorianus (syn. S. carlsbergensis), which are essential for brewing. The cryotolerant yeast S. bayanus var. uvarum is of great importance for production of some wines. Based on ascospore viability and meiotic recombination of the control parental markers in hybrids, we have shown that there is no complete interspecies post-zygotic isolation between the yeasts S. eubayanus, S. bayanus var. bayanus and S. bayanus var. uvarum. The genetic data presented indicate that all of the three taxa belong to the same species.

  13. Taming wild yeast: potential of conventional and nonconventional yeasts in industrial fermentations.

    Science.gov (United States)

    Steensels, Jan; Verstrepen, Kevin J

    2014-01-01

    Yeasts are the main driving force behind several industrial food fermentation processes, including the production of beer, wine, sake, bread, and chocolate. Historically, these processes developed from uncontrolled, spontaneous fermentation reactions that rely on a complex mixture of microbes present in the environment. Because such spontaneous processes are generally inconsistent and inefficient and often lead to the formation of off-flavors, most of today's industrial production utilizes defined starter cultures, often consisting of a specific domesticated strain of Saccharomyces cerevisiae, S. bayanus, or S. pastorianus. Although this practice greatly improved process consistency, efficiency, and overall quality, it also limited the sensorial complexity of the end product. In this review, we discuss how Saccharomyces yeasts were domesticated to become the main workhorse of food fermentations, and we investigate the potential and selection of nonconventional yeasts that are often found in spontaneous fermentations, such as Brettanomyces, Hanseniaspora, and Pichia spp.

  14. Estimating Hedonic Prices for Stellenbosch wine

    OpenAIRE

    Sanja Lutzeyer

    2008-01-01

    This paper estimates a hedonic price function for Stellenbosch wines to determine the association between market value and different characteristics of these wines. In such a hedonic price function, the price of a bottle of wine is ascribed to the implicit value of its attributes. Besides contributing to both South African and international wine pricing literature, the benefits of developing a hedonic wine pricing model extend to numerous players in the wine industry. Consumers are provided w...

  15. FILAMENTOUS FUNGI ON GRAPES IN CENTRAL SLOVAK WINE REGION

    Directory of Open Access Journals (Sweden)

    Ľubomír Rybárik

    2014-02-01

    Full Text Available The concern about filamentous fungi in the vineyards has traditionally been linked to spoilage of grapes due to fungal growth. The aims of this study were to monitor the mycobiota in Central Slovak wine region. The Central Slovak wine region is divided into seven different subregions. In this work we had ten grape samples from seven various wine growing subregions and eight different villages. Five of these samples were from white grape berries and five were from red grape berries. The sample nr. 7 was without chemical protection (interspecific variety and three samples (nr. 8, 9, 10 were from bio-production. In the samples were determined exogenous contamination (direct platting method and endogenous contamination (surface-disinfected grapes. The exogenous mycobiota was determined by the method that each sample of 50 grape berries without visible damage was direct plated on to a DRBC agar medium. In exogenous contamination was detected 17 different genera Alternaria, Arthrinium, Aspergillus, Bipolaris, Botrytis, Cladosporium, Cunninghamella, Epicoccum, Fusarium, Geotrichum, Chaetomium, Mucor, Penicillium, Phoma, Rhizopus, Sordaria, Trichoderma and group Mycelia sterilia in which we included all colony of filamentous fungi that after incubation did not create fruiting bodies necessary for identification to genera level. By the endogenous contamination was each sample of 50 grape berries was surface-disinfected with sodium hypochlorite solution (1% for 1 min, rinsed in sterile distilled water three times and plated onto a DRBC (Dichloran Rose Bengal Chloramphenicol medium, Merck, Germany. The plates were incubated at 25±1 ºC for 7 days in the dark. By the endogenous plating method was identified 15 different genera from all ten samples Alternaria, Arthrinium, Aspergillus, Botrytis, Cladosporium, Epicoccum, Fusarium, Geotrichum, Gelasinospora, Chaetomium, Mucor, Penicillium, Phoma, Rhizopus, Trichoderma and Mycelia sterilia.

  16. Sea salts as a potential source of food spoilage fungi.

    Science.gov (United States)

    Biango-Daniels, Megan N; Hodge, Kathie T

    2018-02-01

    Production of sea salt begins with evaporation of sea water in shallow pools called salterns, and ends with the harvest and packing of salts. This process provides many opportunities for fungal contamination. This study aimed to determine whether finished salts contain viable fungi that have the potential to cause spoilage when sea salt is used as a food ingredient by isolating fungi on a medium that simulated salted food with a lowered water activity (0.95 a w ). The viable filamentous fungi from seven commercial salts were quantified and identified by DNA sequencing, and the fungal communities in different salts were compared. Every sea salt tested contained viable fungi, in concentrations ranging from 0.07 to 1.71 colony-forming units per gram of salt. In total, 85 fungi were isolated representing seven genera. One or more species of the most abundant genera, Aspergillus, Cladosporium, and Penicillium was found in every salt. Many species found in this study have been previously isolated from low water activity environments, including salterns and foods. We conclude that sea salts contain many fungi that have potential to cause food spoilage as well as some that may be mycotoxigenic. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. MARKETING IMPLICATION IN WINE ECONOMY

    Directory of Open Access Journals (Sweden)

    Ştefan MATEI

    2014-11-01

    Full Text Available The wine, a very complex product in viticulture, has proved its tremendous importance not only to the individual but rational nutrition and increasing national income of a country cultivators (evidenced by the upward trend of the share of crop production horticulture and viticulture in the global economy agricultural. More interesting is, given the continued growth in the number of scientific publications and their quality (at least since the 1980s - where "wine" is the centerpiece of these studies - we can not but be witnessing a growing interest more to this "potion" and found that the growing popularity of wine in the science reveals the emergence of a new academic field, ie "wine economy" (or wine-economy. This study aims to make a foray into "wine economy" and to outline some of the implications of marketing in this area.

  18. Induction of simultaneous and sequential malolactic fermentation in durian wine.

    Science.gov (United States)

    Taniasuri, Fransisca; Lee, Pin-Rou; Liu, Shao-Quan

    2016-08-02

    This study represented for the first time the impact of malolactic fermentation (MLF) induced by Oenococcus oeni and its inoculation strategies (simultaneous vs. sequential) on the fermentation performance as well as aroma compound profile of durian wine. There was no negative impact of simultaneous inoculation of O. oeni and Saccharomyces cerevisiae on the growth and fermentation kinetics of S. cerevisiae as compared to sequential fermentation. Simultaneous MLF did not lead to an excessive increase in volatile acidity as compared to sequential MLF. The kinetic changes of organic acids (i.e. malic, lactic, succinic, acetic and α-ketoglutaric acids) varied with simultaneous and sequential MLF relative to yeast alone. MLF, regardless of inoculation mode, resulted in higher production of fermentation-derived volatiles as compared to control (alcoholic fermentation only), including esters, volatile fatty acids, and terpenes, except for higher alcohols. Most indigenous volatile sulphur compounds in durian were decreased to trace levels with little differences among the control, simultaneous and sequential MLF. Among the different wines, the wine with simultaneous MLF had higher concentrations of terpenes and acetate esters while sequential MLF had increased concentrations of medium- and long-chain ethyl esters. Relative to alcoholic fermentation only, both simultaneous and sequential MLF reduced acetaldehyde substantially with sequential MLF being more effective. These findings illustrate that MLF is an effective and novel way of modulating the volatile and aroma compound profile of durian wine. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Optimization of Processing Technology of Compound Dandelion Wine

    Directory of Open Access Journals (Sweden)

    Wu Jixuan

    2016-01-01

    Full Text Available Exploring dandelion food has been the concern in fields of the food processing and pharmaceutical industry for playing exact curative effect on high-fat-diet induced hepatic steatosis and diuretic activity. Few dandelion foods including drinks and microencapsulation were explored and unilateral dandelion wine were less carried out for its bitter flavour. In tis paper, to optimize the processing technologies of fermented compound wine from dandelion root, the orthogonal experiment design method was used to composite dandelion root powder with glutinous rice and schisandra fruit and optimize the fermenting parameters. Four factors with dandelion content, schisandra content, acidity and sugar content were discussed. The acidity factor was firstly confirmed as 7.0 g/L. The other three factors were confirmed by a series experiments as dandelion 0.55%, schisandra 0.5%, sugar 22%. With nine step processing of mixing substrate, stirring with water, cooking rice, amylase saccharification, pectinase hydrolysis, adjusting juice, fermenting with yeast, fitering, aging, sterilization, a light yellow wine with the special taste with flavour of dandelion, schisandra and rice and less bitter, few index were determined as 14.7% alcohol, 6.85 g/L acidity. A dandelion fermented compound wine with suitable flavour and sanitarian function was developed for enriching the dandelion food.

  20. Identification of the potential inhibitors of malolactic fermentation in wines

    Directory of Open Access Journals (Sweden)

    Renata Vieira da MOTA

    2017-10-01

    Full Text Available Abstract This exploratory work aims to identify the potential inhibitors of lactic bacterial growth and to propose enological practices to guarantee the occurrence of spontaneous malolactic fermentation (MLF in wines from traditional and double-pruning management harvests in southeast Brazil. One white wine from a summer harvest and one red wine from a winter harvest that failed to complete MLF were utilized as comparative models to identify inhibitor compounds to lactic bacteria. Wine composition, alcoholic-fermentation temperature and bacterial strain contribute to the success or failure of MLF. Temperatures below 12 °C during alcoholic fermentation decrease lactic bacterial metabolism and may impair the bacteria’s growth after yeast cells lysis. A must pH below 3.2 in a summer harvest impairs bacterial growth, and the association of low pH with a free-SO2 concentration above 10 mg L-1 may inhibit MLF. For grapes with a high sugar content, harvested in the winter cycle, enologists should keep the alcohol content below 15% and control the alcoholic-fermentation temperature.

  1. Yeast Biodiversity from DOQ Priorat Uninoculated Fermentations.

    Science.gov (United States)

    Padilla, Beatriz; García-Fernández, David; González, Beatriz; Izidoro, Iara; Esteve-Zarzoso, Braulio; Beltran, Gemma; Mas, Albert

    2016-01-01

    Climate, soil, and grape varieties are the primary characteristics of terroir and lead to the definition of various appellations of origin. However, the microbiota associated with grapes are also affected by these conditions and can leave a footprint in a wine that will be part of the characteristics of terroir. Thus, a description of the yeast microbiota within a vineyard is of interest not only to provide a better understanding of the winemaking process, but also to understand the source of microorganisms that maintain a microbial footprint in wine from the examined vineyard. In this study, two typical grape varieties, Grenache and Carignan, have been sampled from four different vineyards in the DOQ Priorat winegrowing region. Afterward, eight spontaneous alcoholic fermentations containing only grapes from one sampling point and of one variety were conducted at laboratory scale. The fermentation kinetics and yeast population dynamics within each fermentation experiment were evaluated. Yeast identification was performed by RFLP-PCR of the 5.8S-ITS region and by sequencing D1/D2 of the 26S rRNA gene of the isolates. The fermentation kinetics did not indicate clear differences between the two varieties of grapes or among vineyards. Approximately 1,400 isolates were identified, exhibiting high species richness in some fermentations. Of all the isolates studied, approximately 60% belong to the genus Hanseniaspora, 16% to Saccharomyces, and 11% to Candida. Other minor genera, such as Hansenula, Issatchenkia, Kluyveromyces, Saccharomycodes, and Zygosaccharomyces, were also found. The distribution of the identified yeast throughout the fermentation process was studied, and Saccharomyces cerevisiae was found to be present mainly at the end of the fermentation process, while Aureobasidium pullulans was isolated primarily during the first days of fermentation in three of the eight spontaneous fermentations. This work highlights the complexity and diversity of the vineyard

  2. Oxidation mechanisms occurring in wines

    OpenAIRE

    Oliveira, Carla Maria; Ferreira, António César Silva; Freitas, Victor De; Silva, Artur M. S.

    2011-01-01

    The present review aims to show the state of the art on the oxidation mechanisms occurring in wines, as well as the methods to monitor, classify and diagnose wine oxidation. Wine oxidation can be divided in enzymatic oxidation and non-enzymatic oxidation. Enzymatic oxidation almost entirely occurs in grape must and is largely correlated with the content of hydroxycinnamates, such as caffeoyltartaric acid and paracoumaroyltartaric acid, and flavan-3-ols. Non-enzymatic oxidation, al...

  3. PROMOTION STRATEGIES IN WINE MARKETING

    OpenAIRE

    Ştefan MATEI

    2014-01-01

    Marketing has proven to be very useful instrument in the wine industry, in fostering comprehensive, cohesive and effective strategies which wineries require to effectively compete in today’s almost saturated wine market. But within wine marketing, the promotion strategy, from our point of view, is the most important component of the winery that can ensure the success in the market or can shorten the life cycle of the product. This being said, the aim of the paper is twofold. Firstly, to deter...

  4. Impact of grape cluster defoliation on TDN potential in cool climate Riesling wines

    Directory of Open Access Journals (Sweden)

    Schüttler Armin

    2015-01-01

    Full Text Available Many cool climate grape vine growing regions are and will be affected by the global climate change. It is likely that increasing temperatures, as well as changing precipitation pattern will impact the wines’ composition and wine styles. In the last decades the sensory concept of German Riesling wines was considered to represent fresh and fruity notes. However, aged wines of this variety are characterized by petrol like aroma, which is not appreciated in modern Riesling wines. The C13-norisoprenoid 1,1,6-trimethyl-1,2-dihydronaphthalene (TDN is considered to be the marker compound for this undesired sensory impression. The biogenesis of this compound is impacted by grape vine growth conditions. Wines made from Riesling grapes grown in warmer climates have higher concentrations of TDN. Therefore “TDN management” will be one of the most challenging tasks in viticulture in Riesling growing regions in general and particularly in cool climate regions. Two approaches considered are the canopy management of the grape vines as well as an appropriate selection of yeast strain for alcoholic fermentation. Therefore, the aim of this project was to study the impact of grape zone defoliation on potential TDN concentrations in grapes, must and finished wines under cool climate conditions, in example of regional conditions of the landmark Hessische Bergstraße, in com- bination with the usage of two commercially available yeast strains during alcoholic fermentation. The experiment consisted of four treatments in a balanced incomplete block design, grape zone defoliation at berry set on the eastern side of the canopy, grape zone defoliation at berry set on eastern and western side of the canopy, grape zone defoliation at veraison on eastern and western side of the canopy, and a non-defoliated treatment. The treatments and repetitions were harvested separately, pressed, and then fermented with two different commercial Saccharomyces cerevisiae strains. Grape

  5. The euryhaline yeast Debaryomyces hansenii has two catalase genes encoding enzymes with differential activity profile.

    Science.gov (United States)

    Segal-Kischinevzky, Claudia; Rodarte-Murguía, Beatriz; Valdés-López, Victor; Mendoza-Hernández, Guillermo; González, Alicia; Alba-Lois, Luisa

    2011-03-01

    Debaryomyces hansenii is a spoilage yeast able to grow in a variety of ecological niches, from seawater to dairy products. Results presented in this article show that (i) D. hansenii has an inherent resistance to H2O2 which could be attributed to the fact that this yeast has a basal catalase activity which is several-fold higher than that observed in Saccharomyces cerevisiae under the same culture conditions, (ii) D. hansenii has two genes (DhCTA1 and DhCTT1) encoding two catalase isozymes with a differential enzymatic activity profile which is not strictly correlated with a differential expression profile of the encoding genes.

  6. New wine world from China: An analysis of competitiveness of the wine industry in Ningxia

    OpenAIRE

    Li, Yuanbo; Bardaji de Azcarate, Isabel

    2016-01-01

    Recently, China has become a huge wine consumer market as well as being an important wine producer. China has the fifth largest global wine consumption and the largest global red wine market (OIV, 2015) with most of the wine consumed (approximately 70%-80%) being produced domestically. With the growing economy and technological advances, the Chinese domestic wine industry has seen significant development. Now, China has the second largest vineyard area (table grape and wine grape) just after ...

  7. Environmental attitudes towards wine tourism

    Directory of Open Access Journals (Sweden)

    Christopher Taylor

    2010-03-01

    Full Text Available Christopher Taylor1, Nelson Barber2, Cynthia Deale31School of Business, Eastern New Mexico University, Portales, Roosevelt County, NM, USA; 2Whittemore School of Business, University of New Hampshire, Durham, NH, USA; 3Department of Hospitality Management, East Carolina University, Greenville, NC , USAAbstract: Wine tourism marketers frequently seek new ways to promote destinations, often executing ecologically sustainable practices. As consumer environmental knowledge of a wine tourism destination increases, consumer attitudes change, influencing perceptions of the environmental policies of a wine region. In this consumer-driven economy, it is therefore important to search for effective ways to market destinations, and one approach is selective marketing. By focusing on consumers in this manner, it is possible to understand better their concerns and motivations, which should aid in marketing and advertising efforts. This study investigated wine consumers environmental concerns and attitudes about wine regions. Results suggest environmental attitudes differed by demographics regarding the impact of wine tourism, providing ideas on further marketing efforts for those involved in wine tourism.Keywords: sustainable wine tourism, green products, wine marketing, consumers

  8. Taxation and Consumption of Wine

    OpenAIRE

    Tsolakis, Dimitris

    1983-01-01

    In this article, the impact that a sales tax might have upon wine consumption and, hence, on the wine and grape growing industries, is analysed. Implications for government revenue are also considered. It is shown that the relative responsiveness of supply and demand, rather than the level in the marketing chain at which a tax is levied, determines where the tax burden finally falls. The imposition of a tax on wine might force certain sectors of the wine and grape industries to undergo a phas...

  9. Is Wine a Financial Parachute?

    OpenAIRE

    Baldi, Lucia; Vandone, Daniela; Peri, Massimo

    2010-01-01

    This paper analyzes the relationship between Global Wine Industry Share Price Indexes and composite stock market indexes using a Threshold Vector Error Correction Model (TVECM), aiming to investigate if investments in the wine sector play a role in determining financial risk and return to investors who include it in their portfolio. Whilst in most of the literature analyses the return of investments of fine wine, this paper places the focus to “normal” (i.e. non‐fine) wine, using data from th...

  10. Yeast Population Dynamics in Spontaneous and Inoculated Alcoholic Fermentations of Zametovka Must

    Directory of Open Access Journals (Sweden)

    Franc Cus

    2002-01-01

    Full Text Available Inoculated fermentations, which are more rapid and more reliable than spontaneous fermentations, and assure predictable wine quality, are nowadays prevalent in Slovenia’s large-scale wine production. However, spontaneous fermentation strengthens local characteristics of wine and offers opportunities for technological innovation. In the 1999 vintage, spontaneous and inoculated fermentations of Zametovka (Vitis vinifera grape must were studied. Zametovka is the main red variety in production of traditional Slovene red blend wine, Cvicek. The diversity of yeast species and strains in both of the investigated fermentations was determined by molecular and traditional identification methods. The outset of alcoholic fermentation, yeast growth kinetics, and yeast population dynamics presents the main differences between the examined fermentations. Yeast population diversity was higher in the spontaneous process. Dominant yeast isolates from spontaneous fermentation were identified as Candida stellata, Hanseniaspora uvarum and Saccharomyces cerevisiae; whereas Saccharomyces bayanus, Pichia kluyveri, Pichia membranifaciens and Torulaspora delbrueckiim were found less frequently. Dominant species in the inoculated fermentation was Saccharomyces cerevisiae; other species found in smaller numbers were Candida stellata, Hanseniaspora uvarum and Debaryomyces hansenii var. hansenii. Using PFGE, we were able to distinguish among 15 different Saccharomyces cerevisiae strains and three different Saccharomyces bayanus strains isolated from spontaneous fermentation, whereas, in the case of inoculated fermentation, only two Saccharomyces cerevisiae strains were found. Their chromosomal patterns coincide with the chromosomal patterns of the starter culture strains.

  11. Adaptive evolution of Saccharomyces cerevisiae with enhanced ethanol tolerance for Chinese rice wine fermentation.

    Science.gov (United States)

    Chen, Shuang; Xu, Yan

    2014-08-01

    High tolerance towards ethanol is a desirable property for the Saccharomyces cerevisiae strains used in the alcoholic beverage industry. To improve the ethanol tolerance of an industrial Chinese rice wine yeast, a sequential batch fermentation strategy was used to adaptively evolve a chemically mutagenized Chinese rice wine G85 strain. The high level of ethanol produced under Chinese rice wine-like fermentation conditions was used as the selective pressure. After adaptive evolution of approximately 200 generations, mutant G85X-8 was isolated and shown to have markedly increased ethanol tolerance. The evolved strain also showed higher osmotic and temperature tolerances than the parental strain. Laboratory Chinese rice wine fermentation showed that the evolved G85X-8 strain was able to catabolize sugars more completely than the parental G85 strain. A higher level of yeast cell activity was found in the fermentation mash produced by the evolved strain, but the aroma profiles were similar between the evolved and parental strains. The improved ethanol tolerance in the evolved strain might be ascribed to the altered fatty acids composition of the cell membrane and higher intracellular trehalose concentrations. These results suggest that adaptive evolution is an efficient approach for the non-recombinant modification of industrial yeast strains.

  12. Qualitative data analysis for an exploratory sensory study of Grechetto wine.

    Science.gov (United States)

    Esti, Marco; González Airola, Ricardo L; Moneta, Elisabetta; Paperaio, Marina; Sinesio, Fiorella

    2010-02-15

    Grechetto is a traditional white-grape vine, widespread in Umbria and Lazio regions in central Italy. Despite the wine commercial diffusion, little literature on its sensory characteristics is available. The present study is an exploratory research conducted with the aim of identifying the sensory markers of Grechetto wine and of evaluating the effect of clone, geographical area, vintage and producer on sensory attributes. A qualitative sensory study was conducted on 16 wines, differing for vintage, Typical Geographic Indication, and clone, collected from 7 wineries, using a trained panel in isolation who referred to a glossary of 133 white wine descriptors. Sixty-five attributes identified by a minimum of 50% of the respondents were submitted to a correspondence analysis to link wine samples to the sensory attributes. Seventeen terms identified as common to all samples are considered as characteristics of Grechetto wine, 10 of which olfactory: fruity, apple, acacia flower, pineapple, banana, floral, herbaceous, honey, apricot and peach. In order to interpret the relationship between design variables and sensory attributes data on 2005 and 2006 wines, the 28 most discriminating descriptors were projected in a principal component analysis. The first principal component was best described by olfactory terms and the second by gustative attributes. Good reproducibility of results was obtained for the two vintages. For one winery, vintage effect (2002-2006) was described in a new principal component analysis model applied on 39 most discriminating descriptors, which globally explained about 84% of the variance. In the young wines the notes of sulphur, yeast, dried fruit, butter, combined with herbaceous fresh and tropical fruity notes (melon, grapefruit) were dominant. During wine aging, sweeter notes, like honey, caramel, jam, become more dominant as well as some mineral notes, such as tuff and flint. Copyright 2009 Elsevier B.V. All rights reserved.

  13. Wine Expertise Predicts Taste Phenotype.

    Science.gov (United States)

    Hayes, John E; Pickering, Gary J

    2012-03-01

    Taste phenotypes have long been studied in relation to alcohol intake, dependence, and family history, with contradictory findings. However, on balance - with appropriate caveats about populations tested, outcomes measured and psychophysical methods used - an association between variation in taste responsiveness and some alcohol behaviors is supported. Recent work suggests super-tasting (operationalized via propylthiouracil (PROP) bitterness) not only associates with heightened response but also with more acute discrimination between stimuli. Here, we explore relationships between food and beverage adventurousness and taste phenotype. A convenience sample of wine drinkers (n=330) were recruited in Ontario and phenotyped for PROP bitterness via filter paper disk. They also filled out a short questionnaire regarding willingness to try new foods, alcoholic beverages and wines as well as level of wine involvement, which was used to classify them as a wine expert (n=110) or wine consumer (n=220). In univariate logisitic models, food adventurousness predicted trying new wines and beverages but not expertise. Likewise, wine expertise predicted willingness to try new wines and beverages but not foods. In separate multivariate logistic models, willingness to try new wines and beverages was predicted by expertise and food adventurousness but not PROP. However, mean PROP bitterness was higher among wine experts than wine consumers, and the conditional distribution functions differed between experts and consumers. In contrast, PROP means and distributions did not differ with food adventurousness. These data suggest individuals may self-select for specific professions based on sensory ability (i.e., an active gene-environment correlation) but phenotype does not explain willingness to try new stimuli.

  14. Improving industrial yeast strains: exploiting natural and artificial diversity.

    Science.gov (United States)

    Steensels, Jan; Snoek, Tim; Meersman, Esther; Picca Nicolino, Martina; Voordeckers, Karin; Verstrepen, Kevin J

    2014-09-01

    Yeasts have been used for thousands of years to make fermented foods and beverages, such as beer, wine, sake, and bread. However, the choice for a particular yeast strain or species for a specific industrial application is often based on historical, rather than scientific grounds. Moreover, new biotechnological yeast applications, such as the production of second-generation biofuels, confront yeast with environments and challenges that differ from those encountered in traditional food fermentations. Together, this implies that there are interesting opportunities to isolate or generate yeast variants that perform better than the currently used strains. Here, we discuss the different strategies of strain selection and improvement available for both conventional and nonconventional yeasts. Exploiting the existing natural diversity and using techniques such as mutagenesis, protoplast fusion, breeding, genome shuffling and directed evolution to generate artificial diversity, or the use of genetic modification strategies to alter traits in a more targeted way, have led to the selection of superior industrial yeasts. Furthermore, recent technological advances allowed the development of high-throughput techniques, such as 'global transcription machinery engineering' (gTME), to induce genetic variation, providing a new source of yeast genetic diversity. © 2014 The Authors. FEMS Microbiology Reviews published by John Wiley & Sons Ltd on behalf of Federation of European Microbiological Societies.

  15. Improving industrial yeast strains: exploiting natural and artificial diversity

    Science.gov (United States)

    Steensels, Jan; Snoek, Tim; Meersman, Esther; Nicolino, Martina Picca; Voordeckers, Karin; Verstrepen, Kevin J

    2014-01-01

    Yeasts have been used for thousands of years to make fermented foods and beverages, such as beer, wine, sake, and bread. However, the choice for a particular yeast strain or species for a specific industrial application is often based on historical, rather than scientific grounds. Moreover, new biotechnological yeast applications, such as the production of second-generation biofuels, confront yeast with environments and challenges that differ from those encountered in traditional food fermentations. Together, this implies that there are interesting opportunities to isolate or generate yeast variants that perform better than the currently used strains. Here, we discuss the different strategies of strain selection and improvement available for both conventional and nonconventional yeasts. Exploiting the existing natural diversity and using techniques such as mutagenesis, protoplast fusion, breeding, genome shuffling and directed evolution to generate artificial diversity, or the use of genetic modification strategies to alter traits in a more targeted way, have led to the selection of superior industrial yeasts. Furthermore, recent technological advances allowed the development of high-throughput techniques, such as ‘global transcription machinery engineering’ (gTME), to induce genetic variation, providing a new source of yeast genetic diversity. PMID:24724938

  16. Glycosylceramide modifies the flavor and metabolic characteristics of sake yeast

    Directory of Open Access Journals (Sweden)

    Jannatul Ferdouse

    2018-05-01

    Full Text Available In the manufacture of sake, Japanese traditional rice wine, sake yeast is fermented with koji, which is steamed rice fermented with the non-pathogenic fungus Aspergillus oryzae. During fermentation, sake yeast requires lipids, such as unsaturated fatty acids and sterols, in addition to substances provided by koji enzymes for fermentation. However, the role of sphingolipids on the brewing characteristics of sake yeast has not been studied. In this study, we revealed that glycosylceramide, one of the sphingolipids abundant in koji, affects yeast fermentation. The addition of soy, A. oryzae, and Grifola frondosa glycosylceramide conferred a similar effect on the flavor profiles of sake yeast. In particular, the addition of A. oryzae and G. frondosa glycosylceramide were very similar in terms of the decreases in ethyl caprylate and ethyl 9-decenoate. The addition of soy glycosylceramide induced metabolic changes to sake yeast such as a decrease in glucose, increases in ethanol and glycerol and changes in several amino acids and organic acids concentrations. Tricarboxylic acid (TCA cycle, pyruvate metabolism, starch and sucrose metabolism, and glycerolipid metabolism were overrepresented in the cultures incubated with sake yeast and soy glycosylceramide. This is the first study of the effect of glycosylceramide on the flavor and metabolic profile of sake yeast.

  17. Biotechnology of non-Saccharomyces yeasts--the ascomycetes.

    Science.gov (United States)

    Johnson, Eric A

    2013-01-01

    Saccharomyces cerevisiae and several other yeast species are among the most important groups of biotechnological organisms. S. cerevisiae and closely related ascomycetous yeasts are the major producer of biotechnology products worldwide, exceeding other groups of industrial microorganisms in productivity and economic revenues. Traditional industrial attributes of the S. cerevisiae group include their primary roles in food fermentations such as beers, cider, wines, sake, distilled spirits, bakery products, cheese, sausages, and other fermented foods. Other long-standing industrial processes involving S. cerevisae yeasts are production of fuel ethanol, single-cell protein (SCP), feeds and fodder, industrial enzymes, and small molecular weight metabolites. More recently, non-Saccharomyces yeasts (non-conventional yeasts) have been utilized as industrial organisms for a variety of biotechnological roles. Non-Saccharomyces yeasts are increasingly being used as hosts for expression of proteins, biocatalysts and multi-enzyme pathways for the synthesis of fine chemicals and small molecular weight compounds of medicinal and nutritional importance. Non-Saccharomyces yeasts also have important roles in agriculture as agents of biocontrol, bioremediation, and as indicators of environmental quality. Several of these products and processes have reached commercial utility, while others are in advanced development. The objective of this mini-review is to describe processes currently used by industry and those in developmental stages and close to commercialization primarily from non-Saccharomyces yeasts with an emphasis on new opportunities. The utility of S. cerevisiae in heterologous production of selected products is also described.

  18. Glycosylceramide modifies the flavor and metabolic characteristics of sake yeast.

    Science.gov (United States)

    Ferdouse, Jannatul; Yamamoto, Yuki; Taguchi, Seiga; Yoshizaki, Yumiko; Takamine, Kazunori; Kitagaki, Hiroshi

    2018-01-01

    In the manufacture of sake, Japanese traditional rice wine, sake yeast is fermented with koji, which is steamed rice fermented with the non-pathogenic fungus Aspergillus oryzae . During fermentation, sake yeast requires lipids, such as unsaturated fatty acids and sterols, in addition to substances provided by koji enzymes for fermentation. However, the role of sphingolipids on the brewing characteristics of sake yeast has not been studied. In this study, we revealed that glycosylceramide, one of the sphingolipids abundant in koji, affects yeast fermentation. The addition of soy, A. oryzae , and Grifola frondosa glycosylceramide conferred a similar effect on the flavor profiles of sake yeast. In particular, the addition of A. oryzae and G. frondosa glycosylceramide were very similar in terms of the decreases in ethyl caprylate and ethyl 9-decenoate. The addition of soy glycosylceramide induced metabolic changes to sake yeast such as a decrease in glucose, increases in ethanol and glycerol and changes in several amino acids and organic acids concentrations. Tricarboxylic acid (TCA) cycle, pyruvate metabolism, starch and sucrose metabolism, and glycerolipid metabolism were overrepresented in the cultures incubated with sake yeast and soy glycosylceramide. This is the first study of the effect of glycosylceramide on the flavor and metabolic profile of sake yeast.

  19. Factors Contributing to a Memorable Wine Route Experience ...

    African Journals Online (AJOL)

    Wine tourism, especially wine festivals and routes, is becoming more popular in South Africa, primarily because it gives wine cellars and wine farms greater publicity and exposure leading to increase in wine sales. The wine farmers or cellars are also expanding their product offering to involve more than just wine tasting ...

  20. 27 CFR 24.193 - Conversion into still wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Conversion into still wine..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Effervescent Wine § 24.193 Conversion into still wine. Sparkling wine or artificially carbonated wine may be dumped for use as still wine. The dumping process will...

  1. 27 CFR 24.294 - Destruction of wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Destruction of wine. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Removal, Return and Receipt of Wine Removals Without Payment of Tax § 24.294 Destruction of wine. (a) General. Wine on bonded wine premises may be destroyed on or off wine...

  2. Reducing the bloater spoilage incidence in fermented green olives during storage

    Directory of Open Access Journals (Sweden)

    Brito, D.

    2002-09-01

    Full Text Available Fermented green olives of the variety “Picholine” were brined in 5% NaCl solutions, which were adjusted to pH 4.00 and 5.00 with lactic acid. Potassium sorbate was added to the brine at 0.05 % and the assays were inoculated with Lactobacillus plantarum strain I159, and Pichia anomala strains S18 from our collection. The pH values and microbial counts including Gram negative bacteria, yeasts and moulds, and lactic acid bacteria were followed during 6 months of storage. Results showed that even if the olives were inoculated with a high gas producing yeast (P. anomala S18, the attack of the fruits by the “bloater” spoilage was drastically reduced in the assays adjusted to pH4, added with potassium sorbate and inoculated with L. plantarum, without affecting the organoleptic characteristics of the product.Aceitunas verdes fermentadas de la variedad Picholine fueron colocadas en soluciones de salmuera al 5% en NaCl, ajustando el pH a 4,00 y 5,00 con ácido láctico. Se agregó sorbato potásico a la salmuera a una concentración del 0,05% y las muestras se inocularon con cepas de Lactobacllius plantarum I159 y Pichia anomala S18 de nuestra procedencia. Los valores del pH y el recuento microbiano incluyendo a las bacterias Gram-negativas, levaduras y mohos y bacterias del ácido láctico se siguieron durante los seis meses de almacenamiento. Los resultados mostraron que incluso inoculando las aceitunas con la levadura (P. anomala S18, productora de alta cantidad de gas, el ataque de los frutos por el alambrado se redujo drásticamente en las muestras ajustadas a pH4, a las que se añadió sorbato potásico e inoculó con Lactobacllius plantarum, sin verse afectadas las características organolépticas del producto.

  3. The health benefits of wine.

    Science.gov (United States)

    German, J B; Walzem, R L

    2000-01-01

    Epidemiologic studies from numerous disparate populations reveal that individuals with the habit of daily moderate wine consumption enjoy significant reductions in all-cause and particularly cardiovascular mortality when compared with individuals who abstain or who drink alcohol to excess. Researchers are working to explain this observation in molecular and nutritional terms. Moderate ethanol intake from any type of beverage improves lipoprotein metabolism and lowers cardiovascular mortality risk. The question now is whether wine, particularly red wine with its abundant content of phenolic acids and polyphenols, confers additional health benefits. Discovering the nutritional properties of wine is a challenging task, which requires that the biological actions and bioavailability of the >200 individual phenolic compounds be documented and interpreted within the societal factors that stratify wine consumption and the myriad effects of alcohol alone. Further challenge arises because the health benefits of wine address the prevention of slowly developing diseases for which validated biomarkers are rare. Thus, although the benefits of the polyphenols from fruits and vegetables are increasingly accepted, consensus on wine is developing more slowly. Scientific research has demonstrated that the molecules present in grapes and in wine alter cellular metabolism and signaling, which is consistent mechanistically with reducing arterial disease. Future research must address specific mechanisms both of alcohol and of polyphenolic action and develop biomarkers of their role in disease prevention in individuals.

  4. [Beer, wine, spirits and mortality].

    Science.gov (United States)

    Grønbaek, M N; Sørensen, T I; Johansen, D; Becker, U; Gottschau, A; Schnohr, P; Hein, H O; Jensen, G

    2001-05-23

    A population based cohort study investigates the association between alcohol intake and mortality from all causes, coronary heart disease and cancer. The design is prospective with baseline assessment of intake of beer, wine and spirits, smoking habits, educational level, physical activity, and body mass index and a total of 257,859 person-years follow-up on mortality. A total of 4,833 participants died, of these 1,075 from coronary heart disease and 1,552 of cancer. Compared with non-drinkers, light drinkers who avoided wine, had a relative risk of death from all causes of 0.90 (0.82-0.99) and those who drank wine had a relative risk of 0.66 (0.55-0.77). Heavy drinkers who avoided wine were at higher risk of death from all causes than were heavy drinkers who included wine in their alcohol intake. Wine drinkers had significantly lower mortality from both coronary heart disease and cancer than did non-wine drinkers (p = 0.007 and p = 0.004, respectively). In conclusion, wine intake may have a beneficial effect on all cause mortality that is additive to that of alcohol. This effect may be attributable to a reduction in death from both coronary heart disease and cancer.

  5. French Wines on the Decline?:

    DEFF Research Database (Denmark)

    Steiner, Bodo

    2004-01-01

    French wines, differentiated by geographic origin, served for many decades as a basis for the French success in the British wine market. However in the early 1990s, market share began to decline. This article explores the values that market participants placed on labelling information on French...

  6. Tasting Wine: A Learning Experience

    Science.gov (United States)

    King, Tanya J.; Donaldson, Jilleen A.; Harry, Emma

    2012-01-01

    This paper describes a field trip by senior undergraduate anthropology students to a local winery, where they participated in a wine-tasting class with winery staff. In response to explicit hints from a wine-tasting facilitator, and more subtle cues from the cultural capital embedded in their surroundings and the winery staff, the students…

  7. Microbial communities in air and wine of a winery at two consecutive vintages.

    Science.gov (United States)

    Pérez-Martín, Fátima; Seseña, Susana; Fernández-González, Mónica; Arévalo, María; Palop, María Llanos

    2014-11-03

    The aim of this study was to assess, both quantitatively and qualitatively, the populations of lactic acid bacteria (LAB) and yeasts in air and wine of a winery, in order to evaluate the possible exchange of microorganisms between them. Samples were taken in a winery located in Castilla-La Mancha (Spain) during the winemaking period of two consecutive vintages (2011 and 2012). The microbial composition was determined by using both a culture-dependent method and a culture-independent method, PCR-denaturing gradient gel electrophoresis (PCR-DGGE). In addition, genetic characterization of isolates from plates was carried out. A high diversity of species was detected in air and wine samples from both vintages. Leuconostoc mesenteroides was the predominant lactic acid bacteria in air from both vintages while Oenococcus oeni was the predominant in wine. Saccharomyces cerevisiae was the most frequently isolated yeast in both air and wine. Typing of O. oeni and S. cerevisiae isolates from air and wine samples showed the presence of coincident genotypes in both samples, that would confirm the exchange of microorganisms between the two environments, air and wine, and furthermore some of these genotypes were also found at samples taken at different vintages, indicating that they would remain in the winery. The results display the influence of the activity taking place in the winery and the moment of fermentation of the wines in tanks, on the microorganisms present in the air and the role of the air for the dispersal of microorganisms within the winery. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Antioxidant Activity of Wines and Related Matters Studied by EPR Spectroscopy

    Czech Academy of Sciences Publication Activity Database

    Stopka, Pavel; Křížová, Jana; Vrchotová, Naděžda; Bábíková, P.; Tříska, Jan; Balík, J.; Kyseláková, M.

    2008-01-01

    Roč. 26, special (2008), s. 49-54 ISSN 1212-1800. [Quality of Moravian and Czech Wine s and their Future. Lednice, 11.09.2008-12.09.2008] R&D Projects: GA ČR(CZ) GA305/07/0242; GA ČR(CZ) GA525/06/1757; GA ČR(CZ) GA104/08/0758 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z40320502 Keywords : antioxidant activity * EPR * wine * vine grape * vine leaf * yeast sediment Subject RIV: GM - Food Processing Impact factor: 0.472, year: 2008

  9. Milk utilization. Part 5. Advances in the production of wine and ethanol from milk

    Energy Technology Data Exchange (ETDEWEB)

    Sienkiewicz, T; Riedel, C L

    1979-01-01

    After defatting, deproteinization, and possible desalting (electrodialysis), the fermentation of sweet and cottage wheys (whole whey, condensed whey, permeate) leads to EtOH and wine and a decrease in sewage loading. The fermentation of whole lactose with Kluyveromyces fragilis occurred after adaption of yeast in 1 L of 100% EtOH from 42 L permeate. The byproduct is a heating gas (methane, CO/sub 2/). After the addition of glucose or sucrose or enzymic cleavage of lactose with beta-galactosidase and fermentation with Saccharomyces cerevisiae a sweet clear wine is produced (10.5% EtOH).

  10. Development and validation of a colorimetric sensor array for fish spoilage monitoring

    DEFF Research Database (Denmark)

    Morsy, Mohamed K.; Zor, Kinga; Kostesha, Natalie

    2016-01-01

    their color changes in response to compounds present in fresh products (hexanal, 1-octane-3-ol) used as negative controls. The colorimetric sensor array was used to follow fish spoilage over time at room temperature for up to 24 h as well as at 4 °C for 9 days. Additionally, fish decay was monitored using......Given the need for non-destructive methods and sensors for food spoilage monitoring, we have evaluated sixteen chemo-sensitive compounds incorporated in an array for colorimetric detection of typical spoilage compounds (trimethylamine, dimethylamine, cadaverine, putrescine) and characterized...

  11. Selection of Ethanol-Tolerant Yeast Hybrids in pH-Regulated Continuous Culture

    OpenAIRE

    Jiménez, Juan; Benítez, Tahía

    1988-01-01

    Hybrids between naturally occurring wine yeast strains and laboratory strains were formed as a method of increasing genetic variability to improve the ethanol tolerance of yeast strains. The hybrids were subjected to competition experiments under continuous culture controlled by pH with increasing ethanol concentrations over a wide range to select the fastest-growing strain at any concentration of ethanol. The continuous culture system was obtained by controlling the dilution rate of a chemos...

  12. Yeast identification: reassessment of assimilation tests as sole universal identifiers.

    Science.gov (United States)

    Spencer, J; Rawling, S; Stratford, M; Steels, H; Novodvorska, M; Archer, D B; Chandra, S

    2011-11-01

    To assess whether assimilation tests in isolation remain a valid method of identification of yeasts, when applied to a wide range of environmental and spoilage isolates. Seventy-one yeast strains were isolated from a soft drinks factory. These were identified using assimilation tests and by D1/D2 rDNA sequencing. When compared to sequencing, assimilation test identifications (MicroLog™) were 18·3% correct, a further 14·1% correct within the genus and 67·6% were incorrectly identified. The majority of the latter could be attributed to the rise in newly reported yeast species. Assimilation tests alone are unreliable as a universal means of yeast identification, because of numerous new species, variability of strains and increasing coincidence of assimilation profiles. Assimilation tests still have a useful role in the identification of common species, such as the majority of clinical isolates. It is probable, based on these results, that many yeast identifications reported in older literature are incorrect. This emphasizes the crucial need for accurate identification in present and future publications. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  13. Technological change in the wine market? The role of QR codes and wine apps in consumer wine purchases

    Directory of Open Access Journals (Sweden)

    Lindsey M. Higgins

    2014-06-01

    Full Text Available As an experiential good, wine purchases in the absence of tastings are often challenging and information-laden decisions. Technology has shaped the way consumers negotiate this complex purchase process. Using a sample of 631 US wine consumers, this research aims to identify the role of mobile applications and QR codes in the wine purchase decision. Results suggest that wine consumers that consider themselves wine connoisseurs or experts, enjoy talking about wine, and are interested in wine that is produced locally, organically, or sustainably are more likely to employ technology in their wine purchase decision. While disruption appears to have occurred on the supply side (number of wine applications available and the number of wine labels with a QR code, this research suggests that relatively little change is occurring on the demand side (a relatively small segment of the population—those already interested in wine—are employing the technology to aid in their purchase decision.

  14. 27 CFR 19.534 - Withdrawals of spirits for use in production of nonbeverage wine and nonbeverage wine products.

    Science.gov (United States)

    2010-04-01

    ... use in production of nonbeverage wine and nonbeverage wine products. 19.534 Section 19.534 Alcohol... Withdrawals of spirits for use in production of nonbeverage wine and nonbeverage wine products. Spirits... bonded wine cellar for use in the production of nonbeverage wine and nonbeverage wine products. (Sec. 455...

  15. Potential wine ageing during transportation

    Directory of Open Access Journals (Sweden)

    Jung Rainer

    2014-01-01

    Full Text Available In a global world, wineries have to satisfy the demand of consumers who wish to drink high quality wines from countries all over the world. To fulfill this request wines have to be transported, crossing thereby great distances from the place of production to the consumer country. At the Institute of Enology of Hochschule Geisenheim University examinations with White-, Rosé- and Red-Wines of different origins which had been transported over longer distances within Europe (Portugal, France, Italy to Germany by trucks were carried out. Shipping of wines was simulated in a climatized cabinet to analyze the influence on wine quality during this way and conditions of transportation. Time and temperature profiles were based on real transport situtations which were recorded during shipping from Germany to Japan using data loggers. White, Rosé and Red wines were transported during 6 to 8 weeks and then were analytically and sensorically compared to those which were stored at a constant temperature of 15 ∘C. Besides the effect of temperature, the movements and vibrations encountered by the wines were also examined. Analytically wines were analyzed for general analytical parameters with Fourier-Transformation-Infrared-Spectroscopie (FTIR, Colour differences (Spectralphotometrie and free and total sulfuric acid with Flow-Injection-Analysis (FIA. Sensory examinations with a trained panel were performed in difference tests in form of rankings and triangular tests. Summarizing the results from the different tests it could be found that transportation had an influence on the potential ageing of wines depending on the wine matrix. Especially high and varying temperatures during transportations over a longer distance and time had negative influences on wine quality. Also the movement of wine at higher temperatures had showed a negative effect whereas transport at cool temperatures even below 0 ∘C did not influence wine characteristics. Sophisticated

  16. 27 CFR 24.77 - Experimental wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Experimental wine. 24.77... OF THE TREASURY LIQUORS WINE Administrative and Miscellaneous Provisions Tax Exempt Wine § 24.77 Experimental wine. (a) General. Any scientific university, college of learning, or institution of scientific...

  17. YMDB: the Yeast Metabolome Database

    Science.gov (United States)

    Jewison, Timothy; Knox, Craig; Neveu, Vanessa; Djoumbou, Yannick; Guo, An Chi; Lee, Jacqueline; Liu, Philip; Mandal, Rupasri; Krishnamurthy, Ram; Sinelnikov, Igor; Wilson, Michael; Wishart, David S.

    2012-01-01

    The Yeast Metabolome Database (YMDB, http://www.ymdb.ca) is a richly annotated ‘metabolomic’ database containing detailed information about the metabolome of Saccharomyces cerevisiae. Modeled closely after the Human Metabolome Database, the YMDB contains >2000 metabolites with links to 995 different genes/proteins, including enzymes and transporters. The information in YMDB has been gathered from hundreds of books, journal articles and electronic databases. In addition to its comprehensive literature-derived data, the YMDB also contains an extensive collection of experimental intracellular and extracellular metabolite concentration data compiled from detailed Mass Spectrometry (MS) and Nuclear Magnetic Resonance (NMR) metabolomic analyses performed in our lab. This is further supplemented with thousands of NMR and MS spectra collected on pure, reference yeast metabolites. Each metabolite entry in the YMDB contains an average of 80 separate data fields including comprehensive compound description, names and synonyms, structural information, physico-chemical data, reference NMR and MS spectra, intracellular/extracellular concentrations, growth conditions and substrates, pathway information, enzyme data, gene/protein sequence data, as well as numerous hyperlinks to images, references and other public databases. Extensive searching, relational querying and data browsing tools are also provided that support text, chemical structure, spectral, molecular weight and gene/protein sequence queries. Because of S. cervesiae's importance as a model organism for biologists and as a biofactory for industry, we believe this kind of database could have considerable appeal not only to metabolomics researchers, but also to yeast biologists, systems biologists, the industrial fermentation industry, as well as the beer, wine and spirit industry. PMID:22064855

  18. Characterisation of palm wine yeast isolates for industrial utilisation

    African Journals Online (AJOL)

    Administrator

    2006-10-02

    Oct 2, 2006 ... Department of Microbiology, Federal University of Technology, P.M.B 1526, Owerri, Nigeria. Accepted 4 .... improve ethanol tolerance and consequently product yield (Thomas et al., ... Elsevier Science Oub. Co. Netherlands.

  19. Diversity of Saccharomyces cerevisiae strains isolated from Borassus akeassii palm wines from Burkina Faso in comparison to other African beverages.

    Science.gov (United States)

    Tapsoba, François; Legras, Jean-Luc; Savadogo, Aly; Dequin, Sylvie; Traore, Alfred Sababenedyo

    2015-10-15

    In South-West of Burkina Faso, palm wine is produced by spontaneous fermentation of the sap from a specific palm tree Borassus akeassii and plays an important role in people's lives. Saccharomyces cerevisiae is the main agent of this alcoholic fermentation but little is known about the diversity of the isolates from palm. In this work, 39 Saccharomyces cerevisiae strains were isolated from palm wine samples collected from 14 sites in Burkina Faso, as well as 7 isolates obtained from sorghum beer (Dolo) from 3 distant sites. Their diversity was analyzed at 12 microsatellite loci, and compared to the genotypes obtained for other African yeast populations isolated from Cocoa hulks from Ghana, sorghum beer from Ivory Coast, palm wine from Djibouti Republic, and to our database of strains from miscellaneous origins (bread, beer, wine, sake, oaks…). The ploidy of these strains has been assessed as well by flow cytometry. Our results show that B. akeassii palm wine contains a specific yeast population of diploid strains, different from Dolo produced in the same area and from other palm wine strains from Ivory Coast, Nigeria, or Djibouti Republic. In contrast, Dolo strains appeared as a group of related and mainly tetraploid strains despite being isolated from different countries. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Aroma modulation of Cabernet Gernischt dry red wine by optimal enzyme treatment strategy in winemaking.

    Science.gov (United States)

    Sun, Wei-Xuan; Hu, Kai; Zhang, Jun-Xiang; Zhu, Xiao-Lin; Tao, Yong-Sheng

    2018-04-15

    Cabernet Gernischt (CG) is a famous Chinese wine grape cultivar, the red wine of which is known for its green trait, especially when produced from grapes cultivated in regions with monsoon climate. To modify CG wine aroma, three enzyme preparations (H. uvarum extracellular enzyme, AR2000, and pectinase) were introduced in different winemaking stages with Saccharomyces cerevisiae. Free and bound aroma compounds in young wines were detected using headspace solid-phase micro-extraction and gas chromatography-mass spectrometry, and aroma characteristics were quantified by trained panelists. Results showed that simultaneous inoculation of enzymes and yeasts improved wine aroma. Partial least-squares regression revealed that the green trait was due mainly to varietal compounds, especially C 6 compounds, and could be partly weakened by fermentative compounds. Moreover, H. uvarum enzyme treatments enriched the acid fruit note of CG wine by enhancing the synergistic effect of varietal volatiles and certain fermentative compounds, such as esters and phenylethyls. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Low molecular-weight phenols in Tannat wines made by alternative winemaking procedures.

    Science.gov (United States)

    Favre, Guzmán; Peña-Neira, Álvaro; Baldi, Cecilia; Hernández, Natalia; Traverso, Sofía; Gil, Graciela; González-Neves, Gustavo

    2014-09-01

    Low molecular weight phenols of Tannat red wines produced by Traditional Maceration (TM), Prefermentative Cold Maceration (PCM), Maceration Enzyme (ENZ) and grape-Seed Tannins additions (ST), were performed and discussed. Alternatives to TM increased wine phenolic contents but unequally, ST increased mainly smaller flavans-3-ol, PCM anthocyanins and ENZ proanthocyanidins (up to 2250 mg/L). However low molecular weight flavan-3-ols remained below 9 mg/L in all wines, showing that there is not necessarily a correspondence between wine richness in total tannins and flavan-3-ols contents at low molecular weight. PCM wines had particularly high concentrations of tyrosol and tryptophol, yeast metabolism derived compounds. The use of grape-seed enological tannins did not increase grape seed derived phenolic compounds such as gallic acid. Caftaric acid was found in concentrations much higher than those reported in other grape varieties. Wine phenolic content and composition was considerably affected by the winemaking procedures tested. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Chemical compounds and mechanisms involved in the formation and stabilization of foam in sparkling wines.

    Science.gov (United States)

    Kemp, Belinda; Condé, Bruna; Jégou, Sandrine; Howell, Kate; Vasserot, Yann; Marchal, Richard

    2018-02-08

    The visual properties of sparkling wine including foam and bubbles are an indicator of sparkling wine quality. Foam properties, particularly foam height (FH) and foam stability (TS), are significantly influenced by the chemical composition of the wine. This review investigates our current knowledge of specific chemical compounds and, the mechanisms by which they influence the foam properties of sparkling wines. Grape and yeast proteins, amino acids, polysaccharides, phenolic compounds, organic acids, fatty acids, ethanol and sugar are examined with respect to their contribution to foam characteristics in sparkling wines made with the Traditional, Transfer, and Charmat and carbonation methods. Contradictory results have been identified that appear to be due to the analytical methods used to measure and quantify compounds and foam. Biopolymer complexes are discussed and absent knowledge with regards to thaumatin-like proteins (TLPs), polysaccharides, amino acids, oak-derived phenolic compounds and organic acids are identified. Future research is also likely to concentrate on visual analysis of sparkling wines by in-depth imaging analysis and specific sensory analysis techniques.

  3. Efficacy of ultraviolet radiation as an alternative technology to inactivate microorganisms in grape juices and wines.

    Science.gov (United States)

    Fredericks, Ilse N; du Toit, Maret; Krügel, Maricel

    2011-05-01

    Since sulphur dioxide (SO(2)) is associated with health risks, the wine industry endeavours to reduce SO(2) levels in wines with new innovative techniques. The aim of this study was, therefore, to investigate the efficacy of ultraviolet radiation (UV)-C (254 nm) as an alternative technology to inactivate microorganisms in grape juices and wines. A pilot-scale UV-C technology (SurePure, South Africa) consisting of an UV-C germicidal lamp (100 W output; 30 W UV-C output) was used to apply UV-C dosages ranging from 0 to 3672 J l(-1), at a constant flow rate of 4000 l h(-1) (Re > 7500). Yeasts, lactic and acetic acid bacteria were singly and co-inoculated into 20 l batches of Chenin blanc juice, Shiraz juice, Chardonnay wine and Pinotage wine, respectively. A dosage of 3672 J l(-1), resulted in an average log(10) microbial reduction of 4.97 and 4.89 in Chardonnay and Pinotage, respectively. In Chenin blanc and Shiraz juice, an average log(10) reduction of 4.48 and 4.25 was obtained, respectively. UV-C efficacy may be influenced by liquid properties such as colour and turbidity. These results had clearly indicated significant (p radiation may stabilize grape juice and wine microbiologically in conjunction with reduced SO(2) levels. Copyright © 2010 Elsevier Ltd. All rights reserved.

  4. Chemical and microbiological analysis of red wines during storage at different temperatures

    Directory of Open Access Journals (Sweden)

    Attila Kántor

    2014-11-01

    for one wine sample. Microbiological parameters were observed during wine storing after filtration through different microfilters. We determined the total count of bacteria (TCB, Acetobacter cells, Lactobacillus cells, yeast and molds in wine samples with classic plate dilution method. The highest quality wines from microbiological properties were wines from 2013, which was filtered through microfilter and aseptically filled into the bottles, but wines from 2011 was filtered through cross-flow filter and samplesdirectly collected from the storage tanks without microfiltration.

  5. AUTOMATION OF CHAMPAGNE WINES PROCESS IN SPARKLING WINE PRESSURE TANK

    Directory of Open Access Journals (Sweden)

    E. V. Lukyanchuk

    2016-08-01

    Full Text Available The wine industry is now successfully solved the problem for the implementation of automation receiving points of grapes, crushing and pressing departments installation continuous fermentation work, blend tanks, production lines ordinary Madeira continuously working plants for ethyl alcohol installations champagne wine in continuous flow, etc. With the development of automation of technological progress productivity winemaking process develops in the following areas: organization of complex avtomatization sites grape processing with bulk transportation of the latter; improving the quality and durability of wines by the processing of a wide applying wine cold and heat, as well as technical and microbiological control most powerful automation equipment; the introduction of automated production processes of continuous technical champagne, sherry wine and cognac alcohol madery; the use of complex automation auxiliary production sites (boilers, air conditioners, refrigeration unitsand other.; complex avtomatization creation of enterprises, and sites manufactory bottling wines. In the wine industry developed more sophisticated schemes of automation and devices that enable the transition to integrated production automation, will create, are indicative automated enterprise serving for laboratories to study of the main problems of automation of production processes of winemaking.

  6. Continuous wine making by gamma-alumina-supported biocatalyst: quality of the wine and distillates.

    Science.gov (United States)

    Loukatos, P; Kiaris, M; Ligas, I; Bourgos, G; Kanellaki, M; Komaitis, M; Koutinas, A A

    2000-10-01

    The main objective of the present work was the removal of aluminum from wines produced by gamma-alumina-supported yeast cells. Reagents such as Na2CO3, NH4OH, albumin, and Ca(OH)2 were used. Calcium in the presence of albumin was effective, whereas other reagents were not so effective. Because of the improved aroma and taste of distillates produced by gamma-alumina-supported biocatalyst, volatile byproducts of distillates were analyzed. They were also assessed by sensory tests. Methanol, acetaldehyde, ethyl acetate, propanol-1, isobutyl alcohol, and amyl alcohols were determined in distillates. It was noted that the amounts of higher alcohols and amyl alcohols decreased as the temperature of fermentation dropped, leading to a product of improved quality and reduced toxicity.

  7. Decreased production of higher alcohols by Saccharomyces cerevisiae for Chinese rice wine fermentation by deletion of Bat aminotransferases.

    Science.gov (United States)

    Zhang, Cui-Ying; Qi, Ya-Nan; Ma, Hong-Xia; Li, Wei; Dai, Long-Hai; Xiao, Dong-Guang

    2015-04-01

    An appropriate level of higher alcohols produced by yeast during the fermentation is one of the most important factors influencing Chinese rice wine quality. In this study, BAT1 and BAT2 single- and double-gene-deletion mutant strains were constructed from an industrial yeast strain RY1 to decrease higher alcohols during Chinese rice wine fermentation. The results showed that the BAT2 single-gene-deletion mutant strain produced best improvement in the production of higher alcohols while remaining showed normal growth and fermentation characteristics. Furthermore, a BAT2 single-gene-deletion diploid engineered strain RY1-Δbat2 was constructed and produced low levels of isobutanol and isoamylol (isoamyl alcohol and active amyl alcohol) in simulated fermentation of Chinese rice wine, 92.40 and 303.31 mg/L, respectively, which were 33.00 and 14.20 % lower than those of the parental strain RY1. The differences in fermentation performance between RY1-Δbat2 and RY1 were minor. Therefore, construction of this yeast strain is important in future development in Chinese wine industry and provides insights on generating yeast strains for other fermented alcoholic beverages.

  8. 27 CFR 24.210 - Classes of wine other than standard wine.

    Science.gov (United States)

    2010-04-01

    ... fermentation wine, produced as provided in § 24.212; (b) Heavy bodied blending wine, produced as provided in...; (f) Vinegar stock, produced as provided in § 24.217; and (g) Wines other than those in classes listed...

  9. Wine tourism among Generations X and Y

    OpenAIRE

    Getz, Donald; Carlsen, Jack

    2008-01-01

    This paper examines the wine tourism experience from the perspective of young adults, specifically Generation X and Y consumers. Both the wine industry and wine tourism destinations have a particular interest in learning more about these age cohorts, as wine consumption and wine-related travel have been dominated by older adults. Little research has focused on Gen X and Y and how they might become more involved. Accordingly, in this paper their motivation for taking a winery tour, level of eg...

  10. Prions in yeast

    OpenAIRE

    Bezdíčka, Martin

    2013-01-01

    The thesis describes yeast prions and their biological effects on yeast in general. It defines the basic characteristics of yeast prions, that distinguish prions from other proteins. The thesis introduces various possibilities of prion formation, and propagation as well as specific types of yeast prions, including various functions of most studied types of prions. The thesis also focuses on chaperones that affect the state of yeast prions in cells. Lastly, the thesis indicates similarities be...

  11. Prevention of the appearance of light-struck taste in white wine = Prevenzione della comparsa del gusto di luce nel vino bianco

    OpenAIRE

    Fracassetti, D.; Gabrielli, M.; Encinas, J.; Manara, M.; Pellegrino, L.; Tirelli, A.

    2016-01-01

    The light-struck taste is a defect of bottled white wine due to the light exposure and involving the riboflavin (RF), as a photosensitizer, and methionine. The reaction pathways lead to the formation of volatile sulfur compounds, methanethiol and dimethyldisulphide, conferring cabbage-like aromas. The development of this defect is limited at low RF concentrations. In this study, the yeast-mediated release of RF, RF degradation kinetics in model solution and white wine, and RF removal by using...

  12. Involvement of bacterial quorum-sensing signals in spoilage of bean sprouts

    DEFF Research Database (Denmark)

    Rasch, Maria; Andersen, Jens Bo; Nielsen, Kristian Fog

    2005-01-01

    Bacterial communication signals, acylated homoserine lactones (AHLs), were extracted from samples of commercial bean sprouts undergoing soft-rot spoilage. Bean sprouts produced in the laboratory did not undergo soft-rot spoilage and did not contain AHLs or AHL-producing bacteria, although...... the bacterial population reached levels similar to those in the commercial sprouts, 10(8) to 10(9) CFU/g. AHL-producing bacteria (Enterobacteriaceae and pseudomonads) were isolated from commercial sprouts, and strains that were both proteolytic and pectinolytic were capable of causing soft-rot spoilage in bean...... sprouts. Thin-layer chromatography and liquid chromatography-high-resolution mass spectrometry revealed the presence of N-3-oxo-hexanoyl-l-homoserine lactone in spoiled bean sprouts and in extracts from pure cultures of bacteria. During normal spoilage, the pH of the sprouts increased due to proteolytic...

  13. Modelling the effect of ethanol on growth rate of food spoilage moulds

    NARCIS (Netherlands)

    Dantigny, P.; Guilmart, A.; Radoi, F.; Bensoussan, M.; Zwietering, M.H.

    2005-01-01

    The effect of ethanol (E) on the radial growth rate (¿) of food spoilage moulds (Aspergillus candidus, Aspergillus flavus, Aspergillus niger, Cladosporium cladosporioides, Eurotium herbariorum, Mucor circinelloides, Mucor racemosus, Paecilomyces variotii, Penicillium chrysogenum, Penicillium

  14. Lactobacilli and tartrazine as causative agents of red-color spoilage in cucumber pickle products.

    Science.gov (United States)

    Pérez-Díaz, I M; Kelling, R E; Hale, S; Breidt, F; McFeeters, R F

    2007-09-01

    The cucumber pickling industry has sporadically experienced spoilage outbreaks in pickled cucumber products characterized by development of red color on the surface of the fruits. Lactobacillus casei and Lactobacillus paracasei were isolated from 2 outbreaks of this spoilage that occurred about 15 y apart during the last 3 decades. Both organisms were shown to produce this spoilage when inoculated into pickled cucumbers while concomitantly degrading the azo dye tartrazine (FD&C yellow nr 5). This food dye is used as a yellow coloring in the brine cover solutions of commercial pickled cucumber products. The red color does not occur in the absence of tartrazine, nor when turmeric is used as a yellow coloring in the pickles. Addition of sodium benzoate to the brine cover solutions of a pickled cucumber product, more specifically hamburger dill pickles, prevented growth of these lactic acid bacteria and the development of the red spoilage.

  15. New wine world from Asia. Development, regional comparison and opportunities for the wine industry in China

    OpenAIRE

    Li, Yuanbo; Bardaji de Azcarate, Isabel

    2017-01-01

    Recently, China has become a huge wine consumer market as China had the fifth largest global wine consumption and the largest global red wine consumption in 2015 with most of the wine consumed (approximately 70%) being produced domestically. With the growing economy and technological advance, the Chinese domestic wine industry has seen significant development. The Chinese wine industry has flourished across the broad territory from the east costal area to the west desert area with distinct cl...

  16. Antibacterial Activity of Zataria multiflora Boiss Essential Oil against Some Fish Spoilage Bacteria

    OpenAIRE

    Mohammad Hashemi; Saber Barkhori-Mehni; Saeed Khanzadi; Mohammad Azizzadeh

    2017-01-01

    Background: The aim of this study was to investigate antimicrobial effect of Zataria multiflora Boiss essential oil (EO) against six fish spoilage bacteria for evaluation of its potential utilization in the preservation of minimally processed fish products. Methods: Firstly, GC-MS analysis of the EO was performed to determine its chemical composition. Then, antibacterial effect of the EO in a range of 0.031 to 4 mg/ml was tested against different fish spoilage bacteria such as Aeromonas h...

  17. The mouthfeel of white wine.

    Science.gov (United States)

    Gawel, Richard; Smith, Paul A; Cicerale, Sara; Keast, Russell

    2017-07-05

    White wine mouthfeel which encompasses the tactile, chemosensory and taste attributes of perceived viscosity, astringency, hotness and bitterness is increasingly being recognized as an important component of overall white wine quality. This review summarizes the physiological basis for the perception of white wine mouthfeel and the direct and interactive effects of white wine composition, specifically those of low molecular weight phenolic compounds, polysaccharides, pH, ethanol, glycerol, dissolved carbon dioxide, and peptides. Ethyl alcohol concentration and pH play a direct role in determining most aspects of mouthfeel perception, and provide an overall framework on which the other minor wine components can interact to influence white wine mouthfeel. Phenolic compounds broadly impact on the mouthfeel by contributing to its viscosity, astringency, hotness and bitterness. Their breadth of influence likely results from their structural diversity which would allow them to activate multiple sensory mechanisms involved in mouthfeel perception. Conversely, polysaccharides have a small modulating effect on astringency and hotness perception, and glycerol does not affect perceived viscosity within the narrow concentration range found in white wine. Many of the major sensory attributes that contribute to the overall impression of mouthfeel are elicited by more than one class compound suggesting that different physiological mechanisms may be involved in the construct of mouthfeel percepts.

  18. Exploring lot-to-lot variation in spoilage bacterial communities on commercial modified atmosphere packaged beef.

    Science.gov (United States)

    Säde, Elina; Penttinen, Katri; Björkroth, Johanna; Hultman, Jenni

    2017-04-01

    Understanding the factors influencing meat bacterial communities is important as these communities are largely responsible for meat spoilage. The composition and structure of a bacterial community on a high-O 2 modified-atmosphere packaged beef product were examined after packaging, on the use-by date and two days after, to determine whether the communities at each stage were similar to those in samples taken from different production lots. Furthermore, we examined whether the taxa associated with product spoilage were distributed across production lots. Results from 16S rRNA amplicon sequencing showed that while the early samples harbored distinct bacterial communities, after 8-12 days storage at 6 °C the communities were similar to those in samples from different lots, comprising mainly of common meat spoilage bacteria Carnobacterium spp., Brochothrix spp., Leuconostoc spp. and Lactococcus spp. Interestingly, abundant operational taxonomic units associated with product spoilage were shared between the production lots, suggesting that the bacteria enable to spoil the product were constant contaminants in the production chain. A characteristic succession pattern and the distribution of common spoilage bacteria between lots suggest that both the packaging type and the initial community structure influenced the development of the spoilage bacterial community. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Amino acid content in red wines obtained from grapevine nitrogen foliar treatments: consumption during the alcoholic fermentation

    Directory of Open Access Journals (Sweden)

    Javier Portu

    2014-12-01

    Full Text Available Nitrogen is an important element for grapevine and winemaking which affects the development of the plant and yeast, and therefore it is important for wine quality. The aim of this work was to study the influence of foliar application to vineyard of proline, phenylalanine and urea and two commercial nitrogen fertilizers, without and with amino acids in their formulation, on the wine amino acid content and their consumption during the alcoholic fermentation. The results showed that these treatments did not affect the amino acid composition in wines. The differences observed for certain amino acids were so small that the concentration of total amino acids was not significantly different among wines. Moreover, it was observed that the higher the content of amino acids in the medium, the greater their consumption during the alcoholic fermentation.

  20. Effect of antioxidant protection of must on volatile compounds and aroma shelf life of Falanghina (Vitis vinifera L.) wine.

    Science.gov (United States)

    Moio, Luigi; Ugliano, Maurizio; Genovese, Alessandro; Gambuti, Angelita; Pessina, Rita; Piombino, Paola

    2004-02-25

    Two vinification methods involving different degrees of antioxidant protection of Falanghina must during prefermentative steps, and referred as HAMP (high antioxidant must protection) and LAMP (low antioxidant must protection), were compared in terms of fermentation performances of four different yeast strains, composition of the volatile fraction of wines at the end of alcoholic fermentation, and shelf life of wines during storage. The use of HAMP technology resulted in wines with lower volatile acidity and higher concentrations of medium-chain fatty acid ethyl esters, acetates, and volatile fatty acids. For two of the four strains a lower concentration of isoamyl alcohol was also observed. HAMP wines also revealed increased shelf life because of the higher concentration of odor active esters at the end of storage and better preservation of varietal aromas.

  1. Use of solid phase microextraction to identify volatile organic compounds in brazilian wines from different grape varieties

    Directory of Open Access Journals (Sweden)

    Natália Cristina Morais Fernandes

    Full Text Available Abstract The Brazilian wine industry has shown significant growth in recent years and the insertion of new concepts, such as geographical indications as signs of quality, has placed Brazil in tune with the tendencies of world wine production. The aim of this work was to apply the Solid Phase Microextraction technique in combination with Gas Chromatography-Mass Spectrometry to study Brazilian wines made from different grape varieties, in order to separate and identify their volatile organic compounds. These substances were identified by comparisons between the spectra obtained with those presented in the NIST library database, and by comparisons with linear retention indices and literature data. The amounts of the compounds were calculated based on the total peak areas of the chromatograms. Forty-seven volatile compounds were identified and grouped into alcohols, aldehydes, fatty acids, esters, hydrocarbons, ketones and terpenes. Most of them belonged to the ester function, conferring a fruity aroma on the wines. The alcohols may have originated from the yeast metabolism, contributing to the alcoholic and floral aromas. Ethyl lactate, 1-hexanol and diethyl maleate were identified in all the varieties, except Merlot. Decanal, methyl citronellate, (E-2-hexenyl-3-methylbutyrate were only found in Merlot, while 2,3-butanediol was only present in the Tannat wines. 2-Phenylethanol was present in all varieties and is recognized as giving pleasant rose and honey attributes to wines. This study showed that the volatile profile of red wines is mainly characterized by esters and higher alcohols. The statistical analysis of the comparison of averages showed a greater amount of averages significantly different in the relative areas of Merlot wine. The Principal Component Analysis showed one grouping composed only of the Merlot wine samples, and this was probably related to the existence of the volatile organic compounds that were specifically identified in

  2. Chemical signaling and insect attraction is a conserved trait in yeasts.

    Science.gov (United States)

    Becher, Paul G; Hagman, Arne; Verschut, Vasiliki; Chakraborty, Amrita; Rozpędowska, Elżbieta; Lebreton, Sébastien; Bengtsson, Marie; Flick, Gerhard; Witzgall, Peter; Piškur, Jure

    2018-03-01

    Yeast volatiles attract insects, which apparently is of mutual benefit, for both yeasts and insects. However, it is unknown whether biosynthesis of metabolites that attract insects is a basic and general trait, or if it is specific for yeasts that live in close association with insects. Our goal was to study chemical insect attractants produced by yeasts that span more than 250 million years of evolutionary history and vastly differ in their metabolism and lifestyle. We bioassayed attraction of the vinegar fly Drosophila melanogaster to odors of phylogenetically and ecologically distinct yeasts grown under controlled conditions. Baker's yeast Saccharomyces cerevisiae , the insect-associated species Candida californica , Pichia kluyveri and Metschnikowia andauensis , wine yeast Dekkera bruxellensis , milk yeast Kluyveromyces lactis , the vertebrate pathogens Candida albicans and Candida glabrata , and oleophilic Yarrowia lipolytica were screened for fly attraction in a wind tunnel. Yeast headspace was chemically analyzed, and co-occurrence of insect attractants in yeasts and flowering plants was investigated through a database search. In yeasts with known genomes, we investigated the occurrence of genes involved in the synthesis of key aroma compounds. Flies were attracted to all nine yeasts studied. The behavioral response to baker's yeast was independent of its growth stage. In addition to Drosophila , we tested the basal hexapod Folsomia candida (Collembola) in a Y-tube assay to the most ancient yeast, Y. lipolytica, which proved that early yeast signals also function on clades older than neopteran insects. Behavioral and chemical data and a search for selected genes of volatile metabolites underline that biosynthesis of chemical signals is found throughout the yeast clade and has been conserved during the evolution of yeast lifestyles. Literature and database reviews corroborate that yeast signals mediate mutualistic interactions between insects and yeasts

  3. Spoilage potential of Pseudomonas species isolated from goat milk.

    Science.gov (United States)

    Scatamburlo, T M; Yamazi, A K; Cavicchioli, V Q; Pieri, F A; Nero, L A

    2015-02-01

    Pseudomonas spp. are usually associated with spoilage microflora of dairy products due to their proteolytic potential. This is of particular concern for protein-based products, such as goat milk cheeses and fermented milks. Therefore, the goal of the present study was to characterize the proteolytic activity of Pseudomonas spp. isolated from goat milk. Goat milk samples (n=61) were obtained directly from bulk tanks on dairy goat farms (n=12), and subjected to a modified International Organization for Standardization (ISO) protocol to determine the number and proteolytic activity of Pseudomonas spp. Isolates (n=82) were obtained, identified by PCR, and subjected to pulsed-field gel electrophoresis with XbaI macro-restriction. Then, the isolates were subjected to PCR to detect the alkaline protease gene (apr), and phenotypic tests were performed to check proteolytic activity at 7°C, 25°C, and 35°C. Mean Pseudomonas spp. counts ranged from 2.9 to 4.8 log cfu/mL, and proteolytic Pseudomonas spp. counts ranged from 1.9 to 4.6 log cfu/mL. All isolates were confirmed to be Pseudomonas spp., and 41 were identified as Pseudomonas fluorescens, which clustered into 5 groups sharing approximately 82% similarity. Thirty-six isolates (46.9%) were positive for the apr gene; and 57 (69.5%) isolates presented proteolytic activity at 7°C, 82 (100%) at 25°C, and 64 (78%) at 35°C. The isolates were distributed ubiquitously in the goat farms, and no relationship among isolates was observed when the goat farms, presence of apr, pulsotypes, and proteolytic activity were taken into account. We demonstrated proteolytic activity of Pseudomonas spp. present in goat milk by phenotypic and genotypic tests and indicated their spoilage potential at distinct temperatures. Based on these findings and the ubiquity of Pseudomonas spp. in goat farm environments, proper monitoring and control of Pseudomonas spp. during production are critical. Copyright © 2015 American Dairy Science Association

  4. AUTOMATION OF CHAMPAGNE WINES PROCESS IN SPARKLING WINE PRESSURE TANK

    OpenAIRE

    E. V. Lukyanchuk; V. A. Khobin; V. A. Khobin

    2016-01-01

    The wine industry is now successfully solved the problem for the implementation of automation receiving points of grapes, crushing and pressing departments installation continuous fermentation work, blend tanks, production lines ordinary Madeira continuously working plants for ethyl alcohol installations champagne wine in continuous flow, etc. With the development of automation of technological progress productivity winemaking process develops in the following areas: organization of complex a...

  5. Quantification of Wine Mixtures with an Electronic Nose and a Human Panel

    Science.gov (United States)

    Aleixandre, Manuel; Cabellos, Juan M.; Arroyo, Teresa; Horrillo, M. C.

    2018-01-01

    In this work, an electronic nose and a human panel were used for the quantification of wines formed by binary mixtures of four white grape varieties and two varieties of red wines at different percentages (from 0 to 100% in 10% steps for the electronic nose and from 0 to 100% in 25% steps for the human panel). The wines were prepared using the traditional method with commercial yeasts. Both techniques were able to quantify the mixtures tested, but it is important to note that the technology of the electronic nose is faster, simpler, and more objective than the human panel. In addition, better results of quantification were also obtained using the electronic nose. PMID:29484296

  6. Indigenous Saccharomyces cerevisiae yeasts as a source of biodiversity for the selection of starters for specific fermentations

    Directory of Open Access Journals (Sweden)

    Capece Angela

    2014-01-01

    Full Text Available The long-time studies on wine yeasts have determined a wide diffusion of inoculated fermentations by commercial starters, mainly of Saccharomyces. Although the use of starter cultures has improved the reproducibility of wine quality, the main drawback to this practice is the lack of the typical traits of wines produced by spontaneous fermentation. These findings have stimulated wine-researchers and wine-makers towards the selection of autochthonous strains as starter cultures. The objective of this study was to investigate the biodiversity of 167 S. cerevisiae yeasts, isolated from spontaneous fermentation of grapes. The genetic variability of isolates was evaluated by PCR amplification of inter-δ region with primer pair δ2/δ12. The same isolates were investigated for characteristics of oenological interest, such as resistance to sulphur dioxide, ethanol and copper and hydrogen sulphide production. On the basis of technological and molecular results, 20 strains were chosen and tested into inoculated fermentations at laboratory scale. The experimental wines were analyzed for the content of some by-products correlated to wine aroma, such as higher alcohols, acetaldehyde, ethyl acetate and acetic acid. One selected strain was used as starter culture to perform fermentation at cellar level. The selection program followed during this research project represents an optimal combination between two different trends in modern winemaking: the use of S. cerevisiae as starter cultures and the starter culture selection for specific fermentations.

  7. Amarone: a modern wine coming from an ancient production technology.

    Science.gov (United States)

    Paronetto, Lanfranco; Dellaglio, Franco

    2011-01-01

    Amarone wine is a renowned dry red wine produced in Valpolicella (Verona, Northern Italy). It is made from local grapes varieties (Corvina, Rondinella, and Molinara) that are slowly dried under natural conditions during the fall into winter. After the postharvest drying, carried out for several weeks in dedicated lofts called fruttaio, the grapes are vinified: crushed, given prefermentative cold maceration, undergo alcoholic fermentation on the skins, malolactic fermentation, and finally maturation. The partially dried grapes are traditionally crushed during the second half of January to February. Because cellar conditions are unfavorable for either alcohol or malolactic fermentation, selected microbial cultures (yeasts and malolactic bacteria) are often necessary to correctly manage fermentation. The progress of both fermentation processes needs constant surveillance. During maturation conducted in vessels or wooden containers (tonneau in durmast oak), clarification and stabilization lead to improvements in quality. Product specifications require that Amarone not be bottled before the wine has been aged for 2years (Anonymous (2010). Disciplinare di produzione dei vini a denominazione di Origine Controllata e Garantita "Amarone della Valpolicella". Gazzetta Ufficiale della Repubblica Italiana. Serie generale n. 84. April 12). Amarone achieved its DOCG (Controlled and Guaranteed Denomination) status in 2010. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. Saccharomyces cerevisiae proteinase A excretion and wine making.

    Science.gov (United States)

    Song, Lulu; Chen, Yefu; Du, Yongjing; Wang, Xibin; Guo, Xuewu; Dong, Jian; Xiao, Dongguang

    2017-11-09

    Proteinase A (PrA), the major protease in Saccharomyces cerevisiae, plays an essential role in zymogen activation, sporulation, and other physiological processes in vivo. The extracellular secretion of PrA often occurs during alcoholic fermentation, especially in the later stages when the yeast cells are under stress conditions, and affects the quality and safety of fermented products. Thus, the mechanism underlying PrA excretion must be explored to improve the quality and safety of fermented products. This paper briefly introduces the structure and physiological function of PrA. Two transport routes of PrA, namely, the Golgi-to-vacuole pathway and the constitutive Golgi-to-plasma membrane pathway, are also discussed. Moreover, the research history and developments on the mechanism of extracellular PrA secretion are described. In addition, it is briefly discussed that calcium homeostasis plays an important role in the secretory pathway of proteins, implying that the regulation of PrA delivery to the plasma membrane requires the involvement of calcium ion. Finally, this review focuses on the effects of PrA excretion on wine making (including Chinese rice wine, grape wine, and beer brewage) and presents strategies to control PrA excretion.

  9. Wine microbiology is driven by vineyard and winery anthropogenic factors.

    Science.gov (United States)

    Grangeteau, Cédric; Roullier-Gall, Chloé; Rousseaux, Sandrine; Gougeon, Régis D; Schmitt-Kopplin, Philippe; Alexandre, Hervé; Guilloux-Benatier, Michèle

    2017-03-01

    The effects of different anthropic activities (vineyard: phytosanitary protection; winery: pressing and sulfiting) on the fungal populations of grape berries were studied. The global diversity of fungal populations (moulds and yeasts) was performed by pyrosequencing. The anthropic activities studied modified fungal diversity. Thus, a decrease in biodiversity was measured for three successive vintages for the grapes of the plot cultivated with Organic protection compared to plots treated with Conventional and Ecophyto protections. The fungal populations were then considerably modified by the pressing-clarification step. The addition of sulfur dioxide also modified population dynamics and favoured the domination of the species Saccharomyces cerevisiae during fermentation. The non-targeted chemical analysis of musts and wines by FT-ICR-MS showed that the wines could be discriminated at the end of alcoholic fermentation as a function of adding SO 2 or not, but also and above all as a function of phytosanitary protection, regardless of whether these fermentations took place in the presence of SO 2 or not. Thus, the existence of signatures in wines of chemical diversity and microbiology linked to vineyard protection has been highlighted. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  10. Presence and changes in populations of yeasts on raw and processed poultry products stored at refrigeration temperature.

    Science.gov (United States)

    Ismail, S A; Deak, T; El-Rahman, H A; Yassien, M A; Beuchat, L R

    2000-12-05

    A study was undertaken to determine populations and profiles of yeast species on fresh and processed poultry products upon purchase from retail supermarkets and after storage at 5 degrees C until shelf life expiration, and to assess the potential role of these yeasts in product spoilage. Fifty samples representing 15 commercial raw, marinated, smoked, or roasted chicken and turkey products were analyzed. Yeast populations were determined by plating on dichloran rose bengal chloramphenicol (DRBC) agar and tryptone glucose yeast extract (TGY) agar. Proteolytic activity was determined using caseinate and gelatin agars and lipolytic activity was determined on plate count agar supplemented with tributyrin. Populations of aerobic microorganisms were also determined. Initial populations of yeasts (log10 cfu/g) ranged from less than 1 (detection limit) to 2.89, and increased by the expiration date to 0.37-5.06, indicating the presence of psychrotrophic species. Highest initial populations were detected in raw chicken breast, wings, and ground chicken, as well as in turkey necks and legs, whereas roasted chicken and turkey products contained less than 1 log10 cfu/g. During storage, yeast populations increased significantly (P chicken, ground chicken, liver, heart and gizzard, and in ground turkey and turkey sausage. Isolates (152 strains) of yeasts from poultry products consisted of 12 species. Yarrowia lipolytica and Candida zeylanoides were predominant, making up 39 and 26% of the isolates, respectively. Six different species of basidiomycetous yeasts representing 24% of the isolates were identified. Most Y. lipolytica strains showed strong proteolytic and lipolytic activities, whereas C. zeylanoides was weakly lipolytic. Results suggest that yeasts, particularly Y. lipolytica, may play a more prominent role than previously recognized in the spoilage of fresh and processed poultry stored at 5 degrees C.

  11. Reducing Salt in Raw Pork Sausages Increases Spoilage and Correlates with Reduced Bacterial Diversity.

    Science.gov (United States)

    Fougy, Lysiane; Desmonts, Marie-Hélène; Coeuret, Gwendoline; Fassel, Christine; Hamon, Erwann; Hézard, Bernard; Champomier-Vergès, Marie-Christine; Chaillou, Stéphane

    2016-07-01

    Raw sausages are perishable foodstuffs; reducing their salt content raises questions about a possible increased spoilage of these products. In this study, we evaluated the influence of salt reduction (from 2.0% to 1.5% [wt/wt]), in combination with two types of packaging (modified atmosphere [50% mix of CO2-N2] and vacuum packaging), on the onset of spoilage and on the diversity of spoilage-associated bacteria. After 21 days of storage at 8°C, spoilage was easily observed, characterized by noticeable graying of the products and the production of gas and off-odors defined as rancid, sulfurous, or sour. At least one of these types of spoilage occurred in each sample, and the global spoilage intensity was more pronounced in samples stored under modified atmosphere than under vacuum packaging and in samples with the lower salt content. Metagenetic 16S rRNA pyrosequencing revealed that vacuum-packaged samples contained a higher total bacterial richness (n = 69 operational taxonomic units [OTUs]) than samples under the other packaging condition (n = 46 OTUs). The core community was composed of 6 OTUs (Lactobacillus sakei, Lactococcus piscium, Carnobacterium divergens, Carnobacterium maltaromaticum, Serratia proteamaculans, and Brochothrix thermosphacta), whereas 13 OTUs taxonomically assigned to the Enterobacteriaceae, Enterococcaceae, and Leuconostocaceae families comprised a less-abundant subpopulation. This subdominant community was significantly more abundant when 2.0% salt and vacuum packaging were used, and this correlated with a lower degree of spoilage. Our results demonstrate that salt reduction, particularly when it is combined with CO2-enriched packaging, promotes faster spoilage of raw sausages by lowering the overall bacterial diversity (both richness and evenness). Our study takes place in the context of raw meat product manufacturing and is linked to a requirement for salt reduction. Health guidelines are calling for a reduction in dietary salt intake

  12. Reducing Salt in Raw Pork Sausages Increases Spoilage and Correlates with Reduced Bacterial Diversity

    Science.gov (United States)

    Fougy, Lysiane; Desmonts, Marie-Hélène; Coeuret, Gwendoline; Fassel, Christine; Hamon, Erwann; Hézard, Bernard; Champomier-Vergès, Marie-Christine

    2016-01-01

    ABSTRACT Raw sausages are perishable foodstuffs; reducing their salt content raises questions about a possible increased spoilage of these products. In this study, we evaluated the influence of salt reduction (from 2.0% to 1.5% [wt/wt]), in combination with two types of packaging (modified atmosphere [50% mix of CO2-N2] and vacuum packaging), on the onset of spoilage and on the diversity of spoilage-associated bacteria. After 21 days of storage at 8°C, spoilage was easily observed, characterized by noticeable graying of the products and the production of gas and off-odors defined as rancid, sulfurous, or sour. At least one of these types of spoilage occurred in each sample, and the global spoilage intensity was more pronounced in samples stored under modified atmosphere than under vacuum packaging and in samples with the lower salt content. Metagenetic 16S rRNA pyrosequencing revealed that vacuum-packaged samples contained a higher total bacterial richness (n = 69 operational taxonomic units [OTUs]) than samples under the other packaging condition (n = 46 OTUs). The core community was composed of 6 OTUs (Lactobacillus sakei, Lactococcus piscium, Carnobacterium divergens, Carnobacterium maltaromaticum, Serratia proteamaculans, and Brochothrix thermosphacta), whereas 13 OTUs taxonomically assigned to the Enterobacteriaceae, Enterococcaceae, and Leuconostocaceae families comprised a less-abundant subpopulation. This subdominant community was significantly more abundant when 2.0% salt and vacuum packaging were used, and this correlated with a lower degree of spoilage. Our results demonstrate that salt reduction, particularly when it is combined with CO2-enriched packaging, promotes faster spoilage of raw sausages by lowering the overall bacterial diversity (both richness and evenness). IMPORTANCE Our study takes place in the context of raw meat product manufacturing and is linked to a requirement for salt reduction. Health guidelines are calling for a reduction in

  13. PROMOTION STRATEGIES IN WINE MARKETING

    Directory of Open Access Journals (Sweden)

    Ştefan MATEI

    2014-06-01

    Full Text Available Marketing has proven to be very useful instrument in the wine industry, in fostering comprehensive, cohesive and effective strategies which wineries require to effectively compete in today’s almost saturated wine market. But within wine marketing, the promotion strategy, from our point of view, is the most important component of the winery that can ensure the success in the market or can shorten the life cycle of the product. This being said, the aim of the paper is twofold. Firstly, to determine and analyze the steps that are required to create a promotion strategy in the wine industry, by comparing different approaches. Secondly, to identify the instruments of the promotional mix that helps a winery to implement its promotional strategy. Bearing that in mind, the paper starts with some theoretical aspects regarding the promotion strategy and ends by providing a brief overview of the main findings.

  14. The effect of the fungicide captan on Saccharomyces cerevisiae and wine fermentation

    Directory of Open Access Journals (Sweden)

    Scariot Fernando J.

    2016-01-01

    Full Text Available Fungicides, particularly those used during grape maturation, as captan, can affect the natural yeast population of grapes, and can reach grape must affecting wine fermentation. The objective of the present work was to study the effect of captan on the viability and fermentative behavior of S. cerevisiae. S. cerevisiae (BY4741 on exponential phase was treated with captan (0 to 40 μM for different periods, and their cell viability analyzed. Cell membrane integrity, thiols concentration, and reactive oxygen species (ROS accumulation was determined. The fermentation experiments were conducted in synthetic must using wine yeast strain Y904. The results showed that under aerobic conditions, 20 μM of captan reduce 90% of yeast viability in 6 hours. Captan treated cells exhibited alteration of membrane integrity, reduction of thiol compounds and increase in intracellular ROS concentration, suggesting a necrotic and pro-oxidant activity of the fungicide. Fermentative experiments showed that concentrations above 2.5 μM captan completely inhibited fermentation, while a dose dependent fermentation delay associated with the reduction of yeast viability was detected in sub-inhibitory concentrations. Petit mutants increase was also observed. In conclusion, the captan induces yeast necrotic cell death on both aerobic and anaerobic conditions causing fermentation delay and/or sucking fermentations.

  15. Acetate metabolism of Saccharomyces cerevisiae at different temperatures during lychee wine fermentation

    Directory of Open Access Journals (Sweden)

    Yu-hui Shang

    2016-05-01

    Full Text Available The yeast (Saccharomyces cerevisiae strain 2137 involved in lychee wine production was used to investigate acetate metabolism at different temperatures during lychee wine fermentation. Fermentation tests were conducted using lychee juice supplemented with acetic acid. The ability of yeast cells to metabolize acetic acid was stronger at 20 °C than at 25 °C or 30 °C. The addition of acetic acid suppressed the yeast cell growth at the tested temperatures. The viability was higher and the reactive oxygen species concentration was lower at 20 °C than at 30 °C; this result indicated that acid stress adaptation protects S. cerevisiae from acetic-acid-mediated programmed cell death. The acetic acid enhanced the thermal death of yeast at high temperatures. The fermentation temperature modified the metabolism of the yeasts and the activity of related enzymes during deacidification, because less acetaldehyde, less glycerol, more ethanol, more succinic acid and more malic acid were produced, with higher level of acetyl–CoA synthetase and isocitrate lyase activity, at 20 °C.

  16. Inactivation of the Radiation-Resistant Spoilage Bacterium Micrococcus radiodurans

    Science.gov (United States)

    Duggan, D. E.; Anderson, A. W.; Elliker, P. R.

    1963-01-01

    A simplified technique permitting the pipetting of raw puréed meats for quantitative bacteriological study is described for use in determining survival of these non-sporing bacteria, which are exceptionally resistant to radiation. Survival curves, using gamma radiation as the sterilizing agent, were determined in raw beef with four strains of Micrococcus radiodurans. Survival curves of the R1 strain in other meat substrates showed that survival was significantly greater in raw beef and raw chicken than in raw fish or in cooked beef. Resistance was lowest in the buffer. Cells grown in broth (an artificial growth medium) and resuspended in beef did not differ in resistance from cells that had been grown and irradiated in beef. Survival rate was statistically independent of the initial cell concentration, even though there appeared to be a correlation between lower death rate and lower initial cell concentrations. The initial viable count of this culture of the domesticated R1 strain in beef was reduced by a factor of about 10-5 by 3.0 megarad, and 4.0 megarad reduced the initial count by a factor of more than 10-9. Data suggest that M. radiodurans R1 is more resistant to radiation than spore-forming spoilage bacteria for which inactivation rates have been published. PMID:14063780

  17. Prediction of Mold Spoilage for Soy/Polyethylene Composite Fibers

    Directory of Open Access Journals (Sweden)

    Chinmay Naphade

    2015-01-01

    Full Text Available Mold spoilage was determined over 109 days on soy/PE fibers held under controlled temperatures (T ranging from 10°C to 40°C and water activities (aw from 0.11 to 0.98. Water activities were created in sealed containers using saturated salt solutions and placed in temperature-controlled incubators. Soy/PE fibers that were held at 0.823 aw or higher exhibited mold growth at all temperatures. As postulated, increased water activity (greater than 0.89 and temperature (higher than 25°C accelerated mold growth on soy/PE fibers. A slower mold growth was observed on soy/PE fibers that were held at 0.87 aw and 10°C. A Weibull model was employed to fit the observed logarithmic values of T, aw, and an interaction term log⁡T×log⁡aw and was chosen as the final model as it gave the best fit to the raw mold growth data. These growth models predict the expected mold-free storage period of soy/PE fibers when exposed to various environmental temperatures and humidities.

  18. Control of Microbiological Spoilage of Food by Irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, J. [Central Food Research Institute, Budapest (Hungary)

    1978-04-15

    Papers published from 1973 to 1977 in the field of radiation control of microbiological spoilage are reviewed, grouping the subjects according to the type of process and food treated. Various laboratories from 33 countries have recently published data on the subject, radurization of dates, prepackaged vegetables, wet grains, bread, various meats and meat products being reported. The most widespread research activities could be observed in the field of radurization of fish and marine products (shellfish, shrimps). Radiation decontamination of dry food ingredients (enzyme preparates, protein preparates, starch, spices) and cork stoppers was studied in various laboratories. Radappertization research of several animal-protein foods has made remarkable progress and the minimal dose requirements are well established. Combination of radiation treatment with other antimicrobial agents (salt, preservatives, heat, etc.) has been investigated by many laboratories. Foods involved in these investigations were bread, several tropical and subtropical fruits, apple juice, groundnuts, fish fillets and shrimps, but a considerable part of the data relate to model systems. A better understanding of the synergistic effect will require additional knowledge and the continuation of long-range research and development in the field of combined treatments is recommended. (author)

  19. Control of microbiological spoilage of food by irradiation

    International Nuclear Information System (INIS)

    Farkas, J.

    1978-01-01

    Papers published from 1973 to 1977 in the field of radiation control of microbiological spoilage are reviewed, grouping the subjects according to the type of process and food treated. Various laboratories from 33 countries have recently published data on the subject, radurization of dates, prepackaged vegetables, wet grains, bread, various meats and meat products being reported. The most widespread research activities could be observed in the field of radurization of fish and marine products (shellfish, shrimps). Radiation decontamination of dry food ingredients (enzyme preparates, protein preparates, starch, spices) and cork stoppers was studied in various laboratories. Radappertization research of several animal-protein foods has made remarkable progress and the minimal dose requirements are well established. Combination of radiation treatment with other antimicrobial agents (salt, preservatives, heat, etc.) has been investigated by many laboratories. Foods involved in these investigations were bread, several tropical and subtropical fruits, apple juice, groundnuts, fish fillets and shrimps, but a considerable part of the data relate to model systems. A better understanding of the synergistic effect will require additional knowledge and the continuation of long-range research and development in the field of combined treatments is recommended. (author)

  20. Recall costs balanced against spoilage control in Dutch custard.

    Science.gov (United States)

    Velthuis, A G J; Reij, M W; Baritakis, K; Dang, M; van Wagenberg, C P A

    2010-06-01

    The relation between the moment at which a recall of Dutch custard is initiated and the direct costs of this recall was investigated. A simulation model of the custard supply chain was developed to compare scenarios with and without a quarantine of 48 h at the storage of the production plant. The model consists of 3 parts: 1) the distribution of a 24,000-L batch of custard over the supply chain over time is simulated; 2) the time to detect spoilage bacteria with a recontamination test procedure is simulated; and 3) the direct recall costs of custard over the different parts of the supply chain are calculated. Direct recall costs increase from about 25,000 euros/batch to 36,171 euros/batch from 57 to 135 h in the situation without quarantine and from 25,000 euros/batch to 36,648 euros/batch from 123 h to 163 h for the situation with quarantine. Then costs decrease because more and more custard is at the consumer level and only 0.13% of the consumers will ask for a refund. With low true contamination probabilities quarantine is not profitable, but at later detection moments with high probabilities it is. We conclude that a simulation model is a helpful tool to evaluate the efficiency of risk management strategies like end product testing and a quarantine situation. 2010 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  1. Ancient Item Spoilage Ritual Used in Nomadic Burial Rite

    Directory of Open Access Journals (Sweden)

    Beisenov Arman Z.

    2017-07-01

    Full Text Available The article considers the findings of items in ancient burials which were intentionally spoiled prior to deposition in graves. This tradition was widely spread both in terms of chronology and geography, and therefore cannot be attributed to any individual cultures or regions. The authors present new information on the ritual obtained during an investigation of Borsyk burial mound of the Middle Sarmatian period located in West Kazakhstan. The central grave of barrow 6 contained a heavily damaged bronze cauldron. The grave was looted in antiquity. Individual scattered bones of a human skeleton and minor gold foil adornments from the ceremonial dress of a nobleman were discovered in the grave. The authors suggest that the cauldron was intentionally deformed by the participants of an ancient mortuary and memorial ritual. According to the principal hypothesis concerning the essence of this ritual, spoilage of the items was related to the idea of assign the items with “different” and “transcendent” properties, which resulted from the necessity of burying the owner. Cauldrons played an important role in the life of steppe leaders. The authors assume a sacral nature of the use of cauldrons in the culture of steppe peoples associated with feasts, battles, and sacred hunting. Perhaps, there was a tradition of burying cauldrons together with their owners after spoiling the items in view of the concept of the other world and the role of a heroic leader therein.

  2. 27 CFR 24.212 - High fermentation wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false High fermentation wine. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.212 High fermentation wine. High fermentation wine is wine made with the addition of sugar within the limitations prescribed...

  3. 27 CFR 24.293 - Wine for Government use.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Wine for Government use..., DEPARTMENT OF THE TREASURY LIQUORS WINE Removal, Return and Receipt of Wine Removals Without Payment of Tax § 24.293 Wine for Government use. (a) General. Wine may be removed from bonded wine premises, free of...

  4. 27 CFR 24.296 - Taxpaid wine operations.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Taxpaid wine operations..., DEPARTMENT OF THE TREASURY LIQUORS WINE Removal, Return and Receipt of Wine Taxpaid Wine Operations § 24.296 Taxpaid wine operations. (a) General. The proprietor may conduct taxpaid wine operations authorized by...

  5. 27 CFR 24.213 - Heavy bodied blending wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Heavy bodied blending wine..., DEPARTMENT OF THE TREASURY LIQUORS WINE Production of Other Than Standard Wine § 24.213 Heavy bodied blending wine. Heavy bodied blending wine is wine made for blending purposes from grapes or other fruit without...

  6. 27 CFR 24.256 - Bottle aging wine.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Bottle aging wine. 24.256... OF THE TREASURY LIQUORS WINE Storage, Treatment and Finishing of Wine Bottling, Packing, and Labeling of Wine § 24.256 Bottle aging wine. Wine bottled or packed and stored for the purpose of aging need...

  7. 27 CFR 24.311 - Taxpaid wine record.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Taxpaid wine record. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.311 Taxpaid wine record. A proprietor who has taxpaid United States or foreign wine on taxpaid wine premises or on taxpaid wine bottling house...

  8. Environmental attitudes towards wine tourism

    OpenAIRE

    Nelson Barber, Nelson; Taylor,Chris; Deale,Cynthia

    2010-01-01

    Christopher Taylor1, Nelson Barber2, Cynthia Deale31School of Business, Eastern New Mexico University, Portales, Roosevelt County, NM, USA; 2Whittemore School of Business, University of New Hampshire, Durham, NH, USA; 3Department of Hospitality Management, East Carolina University, Greenville, NC , USAAbstract: Wine tourism marketers frequently seek new ways to promote destinations, often executing ecologically sustainable practices. As consumer environmental knowledge of a wine tourism desti...

  9. A cointegration analysis of wine stock indexes

    OpenAIRE

    Sabina Introvigne; Emanuele Bacchiocchi; Daniela Vandone

    2017-01-01

    This paper analyzes price patterns and long-run relationships for both fine wine and non-fine wine, with the aim to highlight price dynamics and co-movements between series, and to exploit potential diversification benefits. Data are from Liv-Ex 100 Fine Wine for fine wine, the Mediobanca Global Wine Industry Share Price for normal wine, and the MSCI World Index as a proxy of the overall stock market. Engle-Granger and Johansen tests were used to detect whether and to what extent the series c...

  10. Different preferences for wine communication

    Directory of Open Access Journals (Sweden)

    Sandro Sillani

    2017-06-01

    Full Text Available This study aimed at verifying the presence of variations in the reactions of different types of audiences to certain communication tools for wine. Five samples of audiences were compared: wine professionals, organic produce specialists, wine tourists, and two samples of general tourists. The following bundle of attributes were considered: name of the grape; information on organic production methods; type of closure; QR code; landscape; advertising language. Diverse audience’s preferences were measured by conjoint analysis. The results have shown a common sensitivity to certain attributes, and a different or contrary sensitivity to others. In particular, all samples have demonstrated that: 1 certified organic wines communicated in standard wine-market style have the potential of becoming market leaders; 2 photographs facilitate the acceptance of technologically-advanced closures; 3 the presence of the QR code in printed advertisements increases the expected value of the product; 4a landscape characterised by holistic “garden viticulture” increases preferences. Textual language was more effective with professionals, while photographic language was more effective with tourists. Supplementary information on the organic production methods, in addition to the mandatory labelling requirements, increased the preferences of professionals and wine tourists, and was counterproductive with the general tourists.

  11. Potential Grape-Derived Contributions to Volatile Ester Concentrations in Wine

    OpenAIRE

    Boss, Paul; Pearce, Anthony; Zhao, Yanjia; Nicholson, Emily; Dennis, Eric; Jeffery, David

    2015-01-01

    Grape composition affects wine flavour and aroma not only through varietal compounds, but also by influencing the production of volatile compounds by yeast. C9 and C12 compounds that potentially influence ethyl ester synthesis during fermentation were studied using a model grape juice medium. It was shown that the addition of free fatty acids, their methyl esters or acyl-carnitine and acyl-amino acid conjugates can increase ethyl ester production in fermentations. The stimulation of ethyl est...

  12. Aerobic Stability and Effects of Yeasts during Deterioration of Non-fermented and Fermented Total Mixed Ration with Different Moisture Levels

    Directory of Open Access Journals (Sweden)

    W. Hao

    2015-06-01

    Full Text Available The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR. The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML, 450 g/kg (medium moisture level, MML, and 500 g/kg (high moisture level, HML, and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM basis, yeast populations significantly increased from 107 to 1010 cfu/g during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to 109 cfu/g DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR.

  13. Aerobic Stability and Effects of Yeasts during Deterioration of Non-fermented and Fermented Total Mixed Ration with Different Moisture Levels.

    Science.gov (United States)

    Hao, W; Wang, H L; Ning, T T; Yang, F Y; Xu, C C

    2015-06-01

    The present experiment evaluated the influence of moisture level and anaerobic fermentation on aerobic stability of total mixed ration (TMR). The dynamic changes in chemical composition and microbial population that occur after air exposure were examined, and the species of yeast associated with the deterioration process were also identified in both non-fermented and fermented TMR to deepen the understanding of aerobic deterioration. The moisture levels of TMR in this experiment were adjusted to 400 g/kg (low moisture level, LML), 450 g/kg (medium moisture level, MML), and 500 g/kg (high moisture level, HML), and both non-fermented and 56-d-fermented TMR were subjected to air exposure to determine aerobic stability. Aerobic deterioration resulted in high losses of nutritional components and largely reduced dry matter digestibility. Non-fermented TMR deteriorated during 48 h of air exposure and the HML treatment was more aerobically unstable. On dry matter (DM) basis, yeast populations significantly increased from 10(7) to 10(10) cfu/g during air exposure, and Candida ethanolica was the predominant species during deterioration in non-fermented TMR. Fermented TMR exhibited considerable resistance to aerobic deterioration. Spoilage was only observed in the HML treatment and its yeast population increased dramatically to 10(9) cfu/g DM when air exposure progressed to 30 d. Zygosaccharomyces bailii was the sole yeast species isolated when spoilage occurred. These results confirmed that non-fermented and fermented TMR with a HML are more prone to spoilage, and fermented TMR has considerable resistance to aerobic deterioration. Yeasts can trigger aerobic deterioration in both non-fermented and fermented TMR. C. ethanolica may be involved in the spoilage of non-fermented TMR and the vigorous growth of Z. bailii can initiate aerobic deterioration in fermented TMR.

  14. Characterization of pectinase activity for enology from yeasts occurring in Argentine Bonarda grape

    Science.gov (United States)

    Merín, María Gabriela; Martín, María Carolina; Rantsiou, Kalliopi; Cocolin, Luca; de Ambrosini, Vilma Inés Morata

    2015-01-01

    Pectinolytic enzymes are greatly important in winemaking due to their ability to degrade pectic polymers from grape, contributing to enhance process efficiency and wine quality. This study aimed to analyze the occurrence of pectinolytic yeasts during spontaneous fermentation of Argentine Bonarda grape, to select yeasts that produce extracellular pectinases and to characterize their pectinolytic activity under wine-like conditions. Isolated yeasts were grouped using PCR-DGGE and identified by partial sequencing of 26S rRNA gene. Isolates comprised 7 genera, with Aureobasidium pullulans as the most predominant pectinolytic species, followed by Rhodotorula dairenensis and Cryptococcus saitoi. No pectinolytic activity was detected among ascomycetous yeasts isolated on grapes and during fermentation, suggesting a low occurrence of pectinolytic yeast species in <