Search

This work focuses on the production of a white wine with a specific organoleptic profile by means of sequential fermentation using immobilized yeast in a system known as "microbial biocapsules". Three fermentation conditions were created: sequential fermentation with immobilized yeast (SqFMB) employing a matrix composed by Aspergillus oryzae (pellet-forming fungus recognized as GRAS), sequential fermentations with non-immobilized yeast cells (SqF), and a control of spontaneous fermentation (SpF). To carry out these fermentations, Pedro Ximénez grape must was used and two non-Saccharomyces yeast strains, Debaryomyces hansenii LR1 and Metschnikowia pulcherimma Primaflora, and the Saccharomyces cerevisiae X5 strain were used. The wines produced were subjected to microbiological and chemical analyses in which metabolites that positively influence the wine profile, such as 1,1-diethoxyethane and decanal, are only produced in the SqFMB condition, and others, like nonanal, were detected in higher concentrations than in SqF and SpF. Microbiological analyses show that less non-Saccharomyces yeasts were isolated in the SqFMB condition than in SqF, which indicates an efficiency in the inoculation and removal method proposed. These results conclude that microbial biocapsules seem to be a good yeast carrier for wine elaboration; however, modulation of some variables like yeast concentration inocula, the employment of preadaptation methods or the use of yeast species with higher fermentative power need to be tested to improve the novel methodology. [ABSTRACT FROM AUTHOR]

Although proline is the most or second most abundant amino acid in wort and grape must, it is not fully consumed by the yeast Saccharomyces cerevisiae during alcoholic fermentation, unlike other amino acids. Our previous studies showed that arginine, the third most abundant amino acid in wort, inhibits the utilization of proline in most strains of S. cerevisiae. Furthermore, we found that some non-Saccharomyces yeasts utilized proline in a specific artificial medium with arginine and proline as the only nitrogen source, but these yeasts were not suitable for beer fermentation due to their low alcohol productivity. For yeasts to be useful for brewing, they need to utilize proline and produce alcohol during fermentation. In this study, 11 S. cerevisiae strains and 10 non-Saccharomyces yeast strains in the Phaff Yeast Culture Collection were identified that utilize proline effectively. Notably, two of these S. cerevisiae strains, UCDFST 40-144 and 68-44, utilize proline and produce sufficient alcohol in the beer fermentation model used. These strains have the potential to create distinctive beer products that are specifically alcoholic but with a reduction in proline in the finished beer.

Abstract Gluten-free products and non-alcoholic beverages have become popular global trends. This study assessed strategies for producing low-alcoholic and low or gluten-free beers. Barley malts were fermented by Saccharomyces cerevisiae or Saccharomycodes ludwigii, and commercial endopeptidase was used to reduce gluten. S. cerevisiae is the most used yeast in alcoholic beer, so vacuum evaporation was used to reduce values of ethanol. S. ludwigii produces less alcohol, however, there was no data reported it would ferment on a semi-industrial scale. The physiochemical parameters in rice malt beers were similar to both yeasts. However, the parameters found differed for beer with barley malt mainly ethanol values, confirming the fermentative difference by tested strains. Volatile composition was evaluated and analyzed by multivariate analysis. The beers proposed by different methodologies: S. cerevisiae with barley malt, peptidase, and evaporation exhibited aromas of floral and featuring beer and spice notes, among others; S. ludwigii fermentation with barley malt and peptidase showcased aromas rich in floral and fresh accents, among others; and, S. cerevisiae with malted rice exhibited notes evoking fruity notes reminiscent of roses and S. ludwigii using malted rice was associated with aromas featuring fruity attributes and emitting rancid notes, among others. Among all the strategies tested, the one using barley malt, enzyme, and S. cerevisiae proved results in terms of aromatic parameters, even with the final boiling process to remove the alcohol.

Copyright of Food & Fermentation Industries is the property of Food & Fermentation Industries and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pure, co-, and sequential fermentations of Hanseniaspora uvarum, H. guilliermondii, and Saccharomyces cerevisiae strains were evaluated to improve the aromatic quality of ciders. In sequential fermentations, Hanseniaspora strains were used as starter, followed by S. cerevisiae inoculation succeeding one, two, and three days of fermentation. Kinetics, physicochemical parameters, and volatile compounds were assessed during 10 days of fermentation. The headspace technique was used to capture the volatile compounds from the ciders obtained in each experiment and analyzed by gas chromatography. Fermentations with pure strains of Hansenisaspora sp. showed a high population (>1010 CFU/mL) but had a low fermentation rate (2.3–3.8 CO2 g/L/d), low consumption of amino acids (20–40 mg/L) with a high residual content, high sugar consumption (80–90 g/L), and low alcohol content (<2.0% v/v). The H. uvarum strain produced a notably high ester content (245 mg/L). In the co-fermentations, H. guilliermondii with S. cerevisiae highlighted a significant production of higher alcohols, similar to that produced by S. cerevisiae alone (152–165 mg/L). In general, the maximum fermentation rate of the sequential inoculations was lower than co-fermentations but showed low residual nitrogen content (<69 mg/L) and good conversion of sugars into ethanol (4.3–5.7% v/v). The highest concentrations of volatile compounds were observed in treatments involving the two non-conventional strains: H. uvarum with S. cerevisiae inoculation after three days (564 mg/L) and H. guilliermondii after just one day (531 mg/L) of fermentation. These differences stemmed from the metabolic activity of the strains. H. uvarum was influenced by the presence of Saccharomyces, whereas H. guilliermondii did not exhibit this effect. Thus, a pure H. uvarum inoculum has the potential to produce a demi-sec cider with low alcohol content and high content of esters, contributing to a fruity aroma. In addition, ciders with sequential inoculation were the most promising for dry cider processing concerning fermentation parameters and bioaroma enrichment. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As research advances, it is generally acknowledged that non -Saccharomyces yeast contribute to the addition of aromatic compounds during mead fermentation. In this experiment, eight different non- Saccharomyces strains and Saccharomyces cerevisiae co-fermentation, their aroma composition, and basic physicochemical parameters were investigated. More than 30 compounds with favourable impact were discovered using solid-phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS). Co-fermentation of non- Saccharomyces spp. and S. cerevisiae can affect the concentration of volatile compounds, so that the mead presents different aroma characteristics. Co-fermented meads of Wickerhamomyces anomalus strains and S. cerevisiae (Wa 27-Sc and Wa 5-Sc) had higher alcohol, acids, aldehyde, and ester concentrations than those fermented with S. cerevisiae alone. In terms of taste, Wa 27-Sc was superior to Wa 5-Sc. Overall, the Wa 27-Sc received the highest score for its strong secondary aroma and good mouthfeel. The results show that the W. anomalus Wa 27 strain has a good potential to produce high quality mead. [ABSTRACT FROM AUTHOR]

In order to enhance the flavor and mouthfeel of Yinhong plum wine, this study investigated the impact of mixed culture fermentation with different non-Saccharomyces yeasts and Saccharomyces cerevisiae on the quality of Yinhong plum wine, aiming to identify the optimal yeast combination for mixed culture fermentation. Four non-Saccharomyce yeasts were selected, including Wickerhamomyces anomalus Wa3, Hanseniaspora uvarum Hu12, three strains of Pichia kluyveri (Pk2A2, PkW2 and PkY2), and Pichia guilliermondii Pg1. Plum wine was fermented by sequential inoculation with non-Saccharomyces and S. cerevisiae strain FX10 at a ratio of 1:1, and its quality was comprehensively evaluated by measuring yeast biomass changes, alcohol concentration, glycerol, organic acids, flavor compounds, and sensory characteristics. The results indicated that the growth of both S. cerevisiae and non-Saccharomyces yeasts was inhibited during mixed culture fermentation. Non-Saccharomyces yeasts died during 6–8 days of primary fermentation. Compared with fermentation with FX10 alone as a control, mixed culture fermentation increased glycerol production, decreased lactate and ethanol contents, and reduced the utilization of reducing sugars in Yinhong plum wine. The concentration of aroma-active esters in Yinhong plum wine from mixed culture fermentation (1.293–4.842 mg/L) was significantly higher than that in the control (1.026 mg/L). Particularly, the wine fermented by PkY2 + FX10 exhibited the highest content of ester compounds, which was 4.72 times higher than that of the control. Principal component analysis (PCA) revealed a significant difference between the wine fermented by P. kluyveri + FX10 and the control group, which was closely associated with elevated levels of ethyl esters and acetic esters, contributing to the intense floral and fruity aroma of Yinhong plum wine. Overall, this study suggested that mixed culture fermentation with P. kluyveri and S. cerevisiae holds promising potential for enhancing the aroma and sensory quality of Yinhong plum wine.

In recent years, demand for low-alcohol and alcohol-free beers has been rising. Of the many methods of producing such beers, many have expensive implementation requirements or drawbacks in terms of beer quality. The exploration of non-Saccharomyces yeast species presents a promising opportunity to overcome these challenges. These yeasts, with their diverse metabolic capabilities and unique flavor profiles, offer the potential to create innovative and flavorful low-alcohol beers. The study investigates the feasibility of using selected non-Saccharomyces yeasts for brewing low-alcohol beers, focusing on fermentation kinetics, physicochemical parameters, and the sensory attributes of the final product. The evaluated yeast species were Kluyveromyces lactis MG971263, Metschnikowia pulcherrima MG971247 and MG971250, Torulaspora delbrueckii MG971248, Wickerhamomyces anomalus MG971261, and W. onychis MG971246. Two strains of Saccharomyces cerevisiae were used as a control. The results of the study show that selected non-Saccharomyces yeast species might be used to produce low-alcohol beers. The non-Saccharomyces yeast allowed the researchers to obtain beers with an alcohol content in the range of 0.5–1.05%, while the control beer brewed with US-05 had an alcohol content of 3.77%. Among the evaluated strains, the strains M. pulcherrima MG971250 and T. delbrueckii MG971248 were found to be rated better in a sensory evaluation than the brewed and low-alcohol strains of S. cerevisiae.

This work focuses on the production of a white wine with a specific organoleptic profile by means of sequential fermentation using immobilized yeast in a system known as “microbial biocapsules”. Three fermentation conditions were created: sequential fermentation with immobilized yeast (SqFMB) employing a matrix composed by Aspergillus oryzae (pellet-forming fungus recognized as GRAS), sequential fermentations with non-immobilized yeast cells (SqF), and a control of spontaneous fermentation (SpF). To carry out these fermentations, Pedro Ximénez grape must was used and two non-Saccharomyces yeast strains, Debaryomyces hansenii LR1 and Metschnikowia pulcherimma Primaflora, and the Saccharomyces cerevisiae X5 strain were used. The wines produced were subjected to microbiological and chemical analyses in which metabolites that positively influence the wine profile, such as 1,1-diethoxyethane and decanal, are only produced in the SqFMB condition, and others, like nonanal, were detected in higher concentrations than in SqF and SpF. Microbiological analyses show that less non-Saccharomyces yeasts were isolated in the SqFMB condition than in SqF, which indicates an efficiency in the inoculation and removal method proposed. These results conclude that microbial biocapsules seem to be a good yeast carrier for wine elaboration; however, modulation of some variables like yeast concentration inocula, the employment of preadaptation methods or the use of yeast species with higher fermentative power need to be tested to improve the novel methodology.

In the last decade, the application of non-Saccharomyces yeasts in oenology as a natural tool to obtain wine diversification and higher quality has aroused great interest. In this work, three Metschnikowia pulcherrima strains, isolated from a vineyard, were characterised through the evaluation of their main oenological properties, antimicrobial activity, and specific enzymatic activities (β-glucosidase, β-lyase, polygalacturonase, and protease). The M. pulcherrima strains did not produce any inhibition against Saccharomyces cerevisiae, while they were able to exert an antimicrobial action against some unwanted bacteria and yeasts frequently present in grape must and potentially causing the alteration of wines. After this preliminary screening, M. pulcherrima AS3C1 has been selected to be used in the winemaking of red grape Vitis vinifera cv. Aglianico on a pilot scale. The effect of the sequential inoculation of M. pulcherrima AS3C1 with a commercial strain of S. cerevisiae was verified using for comparison a single inoculum with S. cerevisiae and a spontaneous fermentation. Our results showed a higher concentration of anthocyanins and catechins in wines obtained by the sequential inoculation of M. pulcherrima AS3C1 and S. cerevisiae. On the basis of the data obtained, M. pulcherrima AS3C1 possesses an enzymatic profile and some oenological properties that could contribute positively to the definition of the chemical composition of wines, suggesting its possible use for red winemaking processes.

Non-conventional yeasts are promising cell factories to produce lipids and oleochemicals, metabolites of industrial interest (e.g., organics acids, esters, and alcohols), and enzymes. They can also use different agro-industrial by-products as substrates within the context of a circular economy. Some of these yeasts can also comprise economic and health burdens as pathogens. Genome-scale metabolic models (GEMs), networks reconstructed based on the genomic and metabolic information of one or more organisms, are great tools to understand metabolic functions and landscapes, as well as propose engineering targets to improve metabolite production or propose novel drug targets. Previous reviews on yeast GEMs have mainly focused on the history and the evaluation of Saccharomyces cerevisiae modeling paradigms or the accessibility and usability of yeast GEMs. However, they did not describe the reconstruction strategies, limitations, validations, challenges, and research gaps of non-conventional yeast GEMs. Herein, we focused on the reconstruction of available non-Saccharomyces GEMs, their validation, underscoring the physiological insights, as well as the identification of both metabolic engineering and drug targets. We also discuss the challenges and knowledge gaps and propose strategies to boost their use and novel reconstructions. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND: Mandarin wine has high added value, which can extend the industry chain of mandarins with excellent economic results. However, innovative fermentation methods are urgently needed to improve the typical taste and flavor characteristics of mandarin wine. In this study, the effect and underlying mechanism of co‐fermentation with Saccharomyces cerevisiae and Schizosaccharomyces pombe on the characteristics of mandarin wine were investigated based on integrated metabolomic and transcriptomic analyses. RESULTS: In comparison with fermentation with only S. cerevisiae, the mandarin wine produced from co‐fermentation with S. cerevisiae and Sc. pombe had a higher pH value, lower malic acid content, and more abundant free amino acids, resulting in better sensory evaluation scores. The introduction of Sc. pombe extended the stage of alcoholic fermentation and enhanced the richness and diversity of volatile compounds, especially floral and fruity aroma compounds, including ethyl hexanoate, ethyl caprylate, ethyl enanthate, 1‐heptanol, and phenylethyl alcohol. he significantly differential metabolites and varying genes were mainly found in pathways of glycolysis, pyruvate metabolism, the citrate cycle, and amino acid metabolism. CONCLUSION: Co‐fermentation with S. cerevisiae and Sc. pombe showed advantages in producing distinctive taste and flavor of mandarin wine in comparison with fermentation with only S. cerevisiae. This study can inspire new co‐fermentation strategies to improve the sensory quality of mandarin wine. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Hakka rice wine is produced from grains by co-fermentation with abundant microbes in an open fermentation environment. Indigenous microbiota and enzymes convert the nutrients in grains into flavor compounds through enzymatic biochemical reactions and microbial metabolism. High-throughput sequencing technology revealed that non-Saccharomyces yeasts dominated the traditional fermentation process, with genera such as Kodamaea ohmeri, Candida orthopsilosis, and Trichosporon asteroides forming a dynamic community that highly correlated with the evolution of 80 volatile compounds in Hakka rice wine. Among the 104 volatile compounds detected by GC–MS, 22 aroma-active compounds with relative odor activity values (ROAV) > 1 were quantified, 11 of which made significant contributions (P

While a recent characterization of non-Saccharomyces thermally inactivated yeasts (TIYs) in a wine-like solution highlighted the release of oenologically relevant compounds and different oxygen consumption rates and antioxidant activity, here the impact of TIYs derived from Saccharomycodes ludwigii (SL), Metschnikowia pulcherrima (MP), Torulaspora delbrueckii (TD), and Saccharomyces cerevisiae (SC), as the reference strain, was evaluated in white wine. Wine treatment with TIYs resulted in an increase in polysaccharide concentration compared to the untreated wine, with SL-TIY exhibiting the highest release. Additionally, all TIYs, particularly SL-TIY, improved protein stability by reducing heat-induced haze formation. The addition of TIYs also demonstrated an effect on color parameters through phenolic compound adsorption, preventing potential browning phenomena. All TIYs significantly impacted the wine’s volatile profile. Overall, it was shown that an improvement in wine quality and stability may be obtained by using TIYs in the winemaking process.

Among many methods to produce low/no-alcohol beers, using special yeasts has gained a substantial interest in the brewing industry. This approach relies on the fact that many non-Saccharomyces yeasts do not utilize maltose, which is the main sugar found in brewer’s wort. Additionally, these yeasts may allow the production of a beer with unique sensory characteristics. The aim of the study was to evaluate the potential of 18 non-Saccharomyces yeast strains in the production of low-alcohol beer. As a control strain, S. cerevisiae US-05 was used. The study consisted of two parts: microbiological evaluation and small-scale fermentations. In the microbiological part, ability to ferment sugars found in a wort, resistance to stress factors, phenolic off-flavor production, and enzymatic activities of β-glucosidase and β-lyase were evaluated. In the second part of the study, yeasts were used to produce a beer from 9.3 °Plato wort. During the fermentation, its dynamics was analyzed. The obtained beers were analyzed regarding their alcohol content, pH, acidity, and color. All of the evaluated strains produced low levels of alcohol. Two of the evaluated strains were characterized by especially high β-glucosidase activity. Based on the obtained results, six of the evaluated strains are promising in brewing.

Non-Saccharomyces yeasts have recently garnered significant interest in oenology. When co-inoculated with Saccharomyces cerevisiae, they contribute to the improvement of wine quality from a sensory point of view. In the present study, a group of yeasts previously isolated from manna and honey by-products were subjected to a genotypic identification. The D1/D2 variable domains of the 26-sRNA gene and the ITS region of the 5.8S gene were sequenced. Additionally, a differentiation of strains was carried out by RAPD-PCR. All strains underwent in vitro screening. Subsequently, a micro-vinification experiment was conducted, focusing on strains with favourable technological characteristics: Lachancea thermotolerans, Starmerella lactis-condensi, and Candida oleophila. These strains were sequentially inoculated alongside a control strain of Saccharomyces cerevisiae. Technological screening revealed that some strains exhibited limited H2S production, ethanol tolerance (up to 8% v/v), resistance to potassium metabisulphite (200 mg/L), osmotic stress tolerance (up to 320 g/L of glucose), and copper resistance (on average 5 mM). The findings from this study can guide the selection of new starters and co-starters for regional wine production.

Summary: The effects of mixed fermentation of non‐Saccharomyces (Pichia fabianii, Kluyveromyces thermotolerans, and Saccharomycopsis fibuligera) with Saccharomyces cerevisiae on the physicochemical indexes and flavour of rice vinegar fermentation were studied. The mixed fermentation increased the activity of β‐glucosidase and esterification enzyme. The β‐glucosidase activity of P. fabianii was 1.6 times higher than that of S. cerevisiae alone, and the esterification enzyme activity was increased by about four times. Compared with the single fermentation of S. cerevisiae, the mixed fermentation of P. fabianii and S. cerevisiae increased the type and content of aromatic esters and produced ethyl acetate and phenethyl acetate. The mixed fermentation of K. thermotolerans and S. cerevisiae made an outstanding contribution to produce higher alcohols. Among them, the content of isobutanol and phenylethanol increased by nearly ten times; the content of isoamylol increased by more than eight times. S. fibuligera provides a unique flavour of phenols because of 2‐methoxy‐4‐ethylphenol and 2‐methoxy‐4‐ethylphenol. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pure, co-, and sequential fermentations of Hanseniaspora uvarum, H. guilliermondii, and Saccharomyces cerevisiae strains were evaluated to improve the aromatic quality of ciders. In sequential fermentations, Hanseniaspora strains were used as starter, followed by S. cerevisiae inoculation succeeding one, two, and three days of fermentation. Kinetics, physicochemical parameters, and volatile compounds were assessed during 10 days of fermentation. The headspace technique was used to capture the volatile compounds from the ciders obtained in each experiment and analyzed by gas chromatography. Fermentations with pure strains of Hansenisaspora sp. showed a high population (>1010 CFU/mL) but had a low fermentation rate (2.3–3.8 CO2 g/L/d), low consumption of amino acids (20–40 mg/L) with a high residual content, high sugar consumption (80–90 g/L), and low alcohol content (v/v). The H. uvarum strain produced a notably high ester content (245 mg/L). In the co-fermentations, H. guilliermondii with S. cerevisiae highlighted a significant production of higher alcohols, similar to that produced by S. cerevisiae alone (152–165 mg/L). In general, the maximum fermentation rate of the sequential inoculations was lower than co-fermentations but showed low residual nitrogen content (v/v). The highest concentrations of volatile compounds were observed in treatments involving the two non-conventional strains: H. uvarum with S. cerevisiae inoculation after three days (564 mg/L) and H. guilliermondii after just one day (531 mg/L) of fermentation. These differences stemmed from the metabolic activity of the strains. H. uvarum was influenced by the presence of Saccharomyces, whereas H. guilliermondii did not exhibit this effect. Thus, a pure H. uvarum inoculum has the potential to produce a demi-sec cider with low alcohol content and high content of esters, contributing to a fruity aroma. In addition, ciders with sequential inoculation were the most promising for dry cider processing concerning fermentation parameters and bioaroma enrichment.

Blackcurrant is well known for its health benefits, but its wine products are understudied. In this research, studies were conducted after non-Saccharomyces and Saccharomyces yeast strain inoculation in less than 20% (w/v) fruit must for blackcurrant fermentation. Three inoculations were carried out on blackcurrant musts, as follows: (1) sequential inoculation with Torulaspora delbrueckii (strain Biodiva) followed by Saccharomyces EC1118 strain; (2) sequential inoculation with Metschnikowia pulcherimma (strain Flavia) followed by EC1118; (3) single-strain inoculation with EC1118 as the control treatment. None of these treatments did alter sugar consumption dynamics. Biodiva inoculation had impacts on both color dynamic parameter changes and final wine color profiles compared to EC1118. The final wine compositions indicate that Biodiva treatment had a significant impact on wine pH and acidity, whereas EC1118 single-strain largely influenced wine ethanol and glycerol contents. Although the total antioxidant capabilities were close among the three produced wines, the monophenol profiles indicate that Biodiva enhanced the total anthocyanin and hydroxycinnamates content but reduced the total flavanol contents in the final wine. EC1118 and Flavia wines contained more total flavanols compared to Biodiva treatment. The nonflavonoid profiles indicate that there were no significant differences among the three treatments. Our findings provide useful information for the application of yeast strains in blackcurrant wine fermentation.

Hanseniaspora vineae (Hv) is a non-Saccharomyces yeast with unique metabolic features, making it appealing for wine production. However, Hv presents high nutritional requirements that may lead to slow fermentation. This study investigated the impact of sequential inoculation of Saccharomyces cerevisiae (Sc) in white winemaking at different time points (24, 48, 74, 100 and 200 h) during Hv fermentation and compared them to simultaneous inoculations. The 200 h protocol extended fermentation by an average of 13 days compared to pure Sc, decreasing with earlier sequential inoculation. Sc wines were richer in isoamyl acetate and ethyl hexanoate than Hv wines, with no significant differences among inoculation protocols. β-phenylethyl acetate was increased in Hv wines, particularly in the 24 h protocol. The 2-phenylethanol concentration was negatively correlated with the S. cerevisiae inoculation delay. Hv altered the wine aroma features, enhancing the compounds associated with rose-like scents. Reducing the Sc inoculation delay aligned Hv with industrial standards while maintaining increased β-phenylethyl acetate production. However, co-inoculation with Sc seems to better meet the Hv requirement without sacrificing the main aromatic features of Hv, demonstrating faster sugar depletion and higher acetate and ethyl ester contents, suggesting that co-inoculation yields a more modulable wine aroma profile.

In view of climate change and the increasingly antagonistic wine market, the exploitation of native genetic resources is revisited in relation to sustainable wine production. ‘Sideritis’ is a late-ripening Greek grape variety, which is quite promising for counteracting wine quality issues associated with the annual temperature rise. The aim of this study was to improve the quality and to enhance the aroma of ‘Sideritis’ wine through the use of native yeasts. To improve vinification, Hanseniaspora opuntiae L1 was used along with Saccharomyces cerevisiae W7 in mixed fermentations (SQ). The addition of H. οpuntiae significantly altered the chemical profile of the wine compared to the single-inoculated fermentations with W7 (IS). H. opuntiae increased all the acetate esters, except for hexyl acetate and (Z)-3-hexen-1-ol acetate. The concentration of 2-phenylethyl acetate, which imparts flowery and sweet notes, exhibited a 2.6-fold increase in SQ as compared to IS wines. SQ also showed higher levels in several ethyl esters, including ethyl butyrate, ethyl heptanoate and ethyl 7-octenoate, which are associated with fruity notes compared to IS. H. opuntiae produced citronellol, a terpene associated with rose and green notes, and increased the overall acceptance of the wine. Present results are thus quite promising for improving ‘Sideritis’ wine quality towards a sustainable wine production in Greece in view of global warming.

Durango State has the denomination of origin for the production of mezcal, which is made from Agave durangensis, mainly in an artisanal way; therefore, differences in the fermentation process affect the quality of the final product. The main objective of the present study was to evaluate the diversity of culturable yeasts involved in the artisanal and semi-technified process of mezcal production in the State of Durango. Three distilleries with different production processes were monitored at different fermentation stages (beginning, mid-fermentation, and end of fermentation) in the spring and summer seasons. A greater diversity was found in the distillery of Nombre de Dios in both the spring and summer production seasons (H’ = 1.464 and 1.332, respectively), since it maintains an artisanal production process. In contrast, the distillery of Durango, where a Saccharomyces cerevisiae commercial inoculum is used to start fermentation, presented low diversity indexes (H’ = 0.7903 and 0.6442) and only S. cerevisiae, Kluyveromyces marxianus, and, sporadically, Pichia manshurica were found. Results suggest that the yeast microbiota involved in mezcal fermentation during the different seasons is affected by the type of inoculum; changes include the presence of some species that were only identified during a specific season in alcoholic fermentation, such as Torulaspora delbrueckii and Pichia kluyveri.

Background: Tostado is a traditional sweet wine from the Designations of Origins (DOs) of Ribeiro and Valdeorras in Galicia (NW Spain). The harvested grapes are air-dried and pressed to increase the concentrations of sugars, acids, and flavour compounds. Therefore, knowledge of the yeasts involved in fermentation under these conditions is essential to guarantee the quality and uniqueness of the valuable, distinctive, and expensive Tostado wines. Methods: Saccharomyces and non-Saccharomyces yeasts were identified using Wallerstein Laboratory (WL) Nutrient Agar and lysine plating, followed by polymerase chain reaction (PCR) amplification, enzymatic digestion, and sequencing. Saccharomyces cerevisiae isolates were further characterised at the strain level using mitochondrial DNA (mtDNA) restriction fragment length polymorphism (RFLP). Statistical analyses were also performed, including different diversity indices, Similarity Percentage (SIMPER) analysis, principal component analysis (PCA), neighbor-joining clustering, parsimony–phylogram, and network plot. In addition, the total acidity, volatile acidity, reducing sugars, and alcoholic strength by volume of the Tostado wines were analysed. Results: A wide diversity of autochthonous yeasts was found, which were predominantly species of oenological relevance, such as Lachancea thermotolerans, Starmerella bacillaris, Hanseniaspora uvarum, Debaryomyces hansenii, Torulaspora delbrueckii, Pichia spp., and Saccharomyces cerevisiae from the must and paste stages of Tostado wine. In addition, 19 different S. cerevisiae strains were identified. This high yeast diversity, which changed from the early stages of fermentation, could contribute to the distinctive characteristics observed in Tostado wine. Conclusions: Characteristic and differentiating chemical and microbiological profiles were found as early as the pre-fermentation stages, which adds value to these special wines that have rarely been studied.

The organoleptic profile and quality of wine are affected by the presence of different non-Saccharomyces species and strains. Therefore, the identification and characterization of non-Saccharomyces yeasts are the first step to understand their function, and to develop a better strain selection program for winemaking. This study investigated the biodiversity of non-Saccharomyces yeasts associated with spontaneous fermentation of Cabernet Sauvignon wines from five sub-regions (Shi Zuishan, Yinchuan, Yu Quanying, Qing Tongxia and Hong Sibu) in Ningxia, China. Yeast species were identified by sequencing the 26S rRNA D1/D2 region, and strains at the subspecies level were discriminated using tandem repeat-tRNA (TRtRNA) PCR analysis. A total of 524 yeast colonies were isolated, and 19 non-Saccharomyces yeast species belonging to 10 genera were identified, including Aureobasidium pullulans, Cryptococcus albidus, Cryptococcus sp., C. flavescens, C. terrestris, C. magnus, Cystofilobasidium ferigula, Candida zemplinina, Filobasidium magnum, Filobasidium sp., F. elegans, Hanseniaspora uvarum, Metschnikowia pimensis, M. pulcherrima, Naganishia albida, Pichia kluyveri, P. kudriavzevii, Rhodotorula glutinis and R. graminis. Hanseniaspora uvarum, C. zemplinina, and M. pulcherrima were the three most dominated species, while other non-Saccharomyces species were only present in the early stage of spontaneous fermentations at different levels. Further, for the yeast discrimination at strain level, 34 profiles were obtained by amplification with primer pairs TtRNASC/5CAG, while 40 profiles were obtained with primer pairs TtRNASC/ISSR-MB. This study explored the diversity of non-Saccharomyces species in Ningxia, China, and made an important contribution of genetic resources for further strain development. [ABSTRACT FROM AUTHOR]

Finding alternatives to the use of chemical inputs to preserve the sanitary and organoleptic quality of food and beverages is essential to meet public health requirements and consumer preferences. In oenology, numerous manufacturers already offer a diverse range of bio-protection yeasts to protect must against microbiological alterations and therefore limit or eliminate sulphites during winemaking. Bio-protection involves selecting non-Saccharomyces yeasts belonging to different genera and species to induce negative interactions with indigenous microorganisms, thereby limiting their development and their impact on the matrix. Although the effectiveness of bio-protection in the winemaking industry has been reported in numerous journals, the underlying mechanisms are not yet well understood. The aim of this review is to examine the current state of the art of field trials and laboratory studies that demonstrate the effects of using yeasts for bio-protection, as well as the interaction mechanisms that may be responsible for these effects. It focuses on the yeast Metschnikowia pulcherrima, particularly recommended for the bio-protection of grape musts. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The use of Saccharomyces and non-Saccharomyces (NS) during wine making is a new concept to keep the wines' local specificity. Different molecular tools were developed to quantify Saccharomyces yeast during winemaking, but for the NS several limitations were detected. In this regard, our work focused on the development of a qPCR method employing propidium monoazide (PMA) for the detection of NS viable cells. Very good correlation parameters and standard curves were obtained during the optimisation method for Saccharomyces reference strain versus NS belonging to Candida stellata and Torulaspora delbrueckii. The detection limit varied from 38 fg/μL to 49 fg/μL which corresponds to quantification limits of 70 CFU/mL to 1.03*10² CFU/mL. The optimised PMA-qPCR method can be considered as a rapid and suitable method for assessing the viable microbial count for both NS yeast species. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Viticulture & Enology / Ciência e Técnica Vitivinícola is the property of EDP Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

With global climate warming, grape berries ripen too fast in warm growing regions especially in grape growing regions in western China, which in turn results in low acidity in grapes and ultimately will cause a great negative impact on the taste and quality of wine. Lachancea thermotolerans (LT) is a non-Saccharomyces yeast that can produce a high yield of lactic acid. The mixed inoculation of LT and Saccharomyces cerevisiae can effectively increase the acidity and reduce the pH of wine, thereby maintaining the microbial and color stability. In this paper, recent progress in the research and application of LT in wine fermentation is reviewed with respect to the basic physiological, biochemical and enological characteristics of LT. Furthermore, the influence of LT on the major metabolites, aroma and color of wine and the molecular mechanism of over-production of lactic acid by LT are reviewed. Finally, the commercial application of LT is outlined. This review is expected to provide a reference for further research on LT to promote its industrial application in wine production.

Spontaneous fermentation may produce complex and unique wines with geographical designations due to the region-specific yeast flora and variations in must characteristics. The current study focused on the yeast diversity and changes in volatile compounds during the spontaneous fermentation of ‘Karasakız’ grapes from three sub-regions of Çanakkale province, Turkey for two vintages (2019 and 2020). This is the first study on the diversity of autochthonous yeasts during wine fermentation of ‘Karasakız’ variety. In the present work, the strains belong to Hanseniaspora uvarum, Starmerella bacillaris, Pichia terricola, Metschnikowia pulcherrima and Zygoascus hellenicus by PCR-RFLP of the ITS region were identified . A total of 272 isolates were identified as S. cerevisiae. Yeast population and diversity changed related to the sub-region and the vintages. However, H. uvarum and S. bacillaris were common denominators of three regions evaluated. H. uvarum was dominant in the early stages of the fermentation, except for Bozcaada 2019 vintage. Bozcaada region also exhibited higher S. cerevisiae strain diversity compared to other regions. 1-Hexanol and 1-octanol gradually decreased during the fermentation of ‘Karasakız’ grapes, while the concentration of isoamyl alcohol, phenylethyl alcohol and ester compounds increased by the fermentation but with some fluctuation.

Proline contributes to the taste and flavor of foods. The yeast Saccharomyces cerevisiae poorly assimilates proline during fermentation processes, resulting in the accumulation of proline in fermentative products. We performed here a screening of in total 1138 yeasts to obtain strains that better utilize proline. Our results suggest that proline utilization occurs in the genera of Zygoascus, Galactomyces, and Magnusiomyces. [ABSTRACT FROM AUTHOR]

Finding alternatives to the use of chemical inputs to preserve the sanitary and organoleptic quality of food and beverages is essential to meet public health requirements and consumer preferences. In oenology, numerous manufacturers already offer a diverse range of bio-protection yeasts to protect must against microbiological alterations and therefore limit or eliminate sulphites during winemaking. Bio-protection involves selecting non-Saccharomyces yeasts belonging to different genera and species to induce negative interactions with indigenous microorganisms, thereby limiting their development and their impact on the matrix. Although the effectiveness of bio-protection in the winemaking industry has been reported in numerous journals, the underlying mechanisms are not yet well understood.The aim of this review is to examine the current state of the art of field trials and laboratory studies that demonstrate the effects of using yeasts for bio-protection, as well as the interaction mechanisms that may be responsible for these effects. It focuses on the yeast Metschnikowia pulcherrima, particularly recommended for the bio-protection of grape musts.

As a biological alternative to the antimicrobial action of SO2, bioprotection has been proposed to winemakers as a means to limit or prevent grape musts microbial alteration. Competition for nitrogenous nutrients and for oxygen are often cited as potential explanations for the effectiveness of bioprotection. This study analyses the effect of a bioprotective M. pulcherrima strain on the growth of one H. valbyensis strain and one H. uvarum strain. Bioprotection efficiency was observed only against H. valbyensis inoculated at the two lowest concentrations. These results indicate a potential species-dependent efficiency of the bioprotective strain and a strong impact of the initial ratio between bioprotective and apiculate yeasts. The analysis of the consumption of nitrogen compounds revealed that leucine, isoleucine, lysine and tryptophan were consumed preferentially by all three strains. The weaker assimilation percentages of these amino acids observed in H. valbyensis at 24 h growth suggest competition with M. pulcherrima that could negatively affects the growth of the apiculate yeast in co-cultures. The slowest rate of O2 consumption of H. valbyensis strain, in comparison with M. pulcherrima, was probably not involved in the bioprotective effect. Non-targeted metabolomic analyses of M. pulcherrima and H. valbyensis co-culture indicate that the interaction between both strains particularly impact lysin and tryptophan metabolisms.

Non-alcoholic beer (NAB) and low-alcoholic beer (LAB) are taking over the market with growing sales. Sustainable recycling and valorization of exhausted brewer’s spent grain (BSG) coming from craft beer is a relevant issue in the brewing process. In this work, recycled BSG and BSG + GJ (supplemented with 10% grape juice) were used as a wort substrate to inoculate Lachancea thermotolerans, Wickeramhomyces anomalus, Torulaspora delbruecki and Pichia kluyveri non-conventional yeasts to produce NABLAB craft beer. Results showed that wort composed of only recycled BSG produced appreciated NAB beers (ethanol concentration from 0.12% to 0.54% v/v), while the addition of 10% grape juice produced LAB beers (ethanol concentration from 0.82 to 1.66% v/v). As expected, volatile compound production was highest with the addition of grape juice. L. thermotolerans showed lactic acid production, characterizing both worts with the production of ethyl butyrate and isoamyl acetate. T. delbrueckii exhibited relevant amounts of hexanol, phenyl ethyl acetate and β-phenyl ethanol (BSG + GJ). W. anomalus and P. kluyveri showed consistent volatile production, but only in BSG + GJ where fermentation activity was exhibited. The overall results indicated that reused BSGs, non-conventional yeasts and grape juice are suitable bioprocesses for specialty NABLAB beer.

The relationship between climate change and viticulture has become increasingly apparent in recent years. Rising temperatures have been a critical factor in early grape ripening. This, in turn, has led to wines with imbalanced acidity and, more importantly, higher alcohol content and pH values. Today, consumers demand high-quality and healthy products, and this trend has extended to wine consumption. Consumers prefer wines with reduced alcohol content due to the health risks associated with alcohol consumption. To meet this demand, researchers have developed modified yeast strains that reduce wine alcohol content during fermentation. These strains ferment less sugar or redirect carbon metabolism. However, their use may pose challenges, such as producing undesired secondary metabolites that can affect wine characteristics. Additionally, consumers are still divided on using genetically modified organisms (GMOs) in food and beverages. This review examines the impact of climate change on wine quality and consumer perception, taking into account new technologies used to reduce wine alcohol content or produce low-alcohol-content wines, such as low-cost techniques like bio-dealcoholization performed by non-GMO wine yeast, Saccharomyces, and non-Saccharomyces.

Abstract Studies on yeasts involved in traditional sorghum beer fermentation in several African countries revealed the presence of two groups: Saccharomyces and non-Saccharomyces. If Saccharomyces strains were reputed for their fermentation performances, the non-Saccharomyces yeast strains have been recognized for their contribution towards the improvement of the beverage's organoleptic quality, justifying their use as aromatic starter. In spite of this contribution, most studies were focused only on Saccharomyces strains as starter. In this work, the non-Saccharomyces yeast strains found in the inoculum of traditional sorghum beer was investigated. Identification of non-Saccharomyces yeast strains by PCR-RLFP followed sequencing of D1/D2 domain revealed the presence of 2 species: Issatckenkia orientalis and Pichia kudriavzevii with Issatckenkia orientalis predominating. Out of the two species, fermentation characteristics showed that Issatckenkia orientalis seemed suitable for sorghum beer production.

Demand for low- or non-alcoholic beers has been growing in recent years. Thus, research is increasingly focusing on non-Saccharomyces species that typically are only able to consume the simple sugars in wort, and therefore have a limited production of alcohol. In this project, new species and strains of non-conventional yeasts were sampled and identified from Finnish forest environments. From this wild yeast collection, a number of Mrakia gelida strains were selected for small-scale fermentation tests and compared with a reference strain, the low-alcohol brewing yeast Saccharomycodes ludwigii. All the M. gelida strains were able to produce beer with an average of 0.7% alcohol, similar to the control strain. One M. gelida strain showing the most promising combination of good fermentation profile and production of desirable flavor active compounds was selected for pilot-scale (40 L) fermentation. The beers produced were matured, filtered, carbonated, and bottled. The bottled beers were then directed for in-house evaluation, and further analyzed for sensory profiles. The beers produced contained 0.6% Alcohol by volume (ABV). According to the sensory analysis, the beers were comparable to those produced by S. ludwigii, and contained detectable fruit notes (banana and plum). No distinct off-flavors were noted. A comprehensive analysis of M. gelida’s resistance to temperature extremes, disinfectant, common preservatives, and antifungal agents would suggest that the strains pose little risk to either process hygiene or occupational safety [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Ethnic Indian people have been domesticating beneficial microorganisms (bacteria, yeasts, and moulds) by their wisdom of ethno-microbiological knowledge for production of flavoured and socio-culturally preferred fermented foods and alcoholic beverages for more than 8000 years. The purpose of this review is to collate the available literatures of diversity of Saccharomyces and non-Saccharomyces species associated with Indian fermented foods and alcoholic beverages. A colossal diversity of enzyme- and alcohol-producing yeasts under the phylum Ascomycota has been reported from Indian fermented foods and alcoholic beverages. The distributions of yeast species show 13.5% of Saccharomyces cerevisiae and 86.5% of some non-Saccharomyces spp. in Indian fermented foods and alcoholic beverages, based on the reported literatures available till date. There is a research gap on prospect of yeasts research in India. Hence, we suggest that validation of traditional knowledge of domestication of functional yeasts needs to be studied to develop the functional genomics platforms for Saccharomyces and non-Saccharomyces spp. in Indian fermented foods and alcoholic beverages. The purpose of this review is to collate the available literatures of diversity of Saccharomyces and non-Saccharomyces spp. in Indian fermented foods and alcoholic beverages. [ABSTRACT FROM AUTHOR]

In this study, the effect of five different Torulaspora delbrueckii strains in combination with an ale type Saccharomyces cerevisiae on physical, chemical, microbiological, aroma composition, and sensory profiles of beer were examined. The ethyl alcohol content of produced beers ranged from 5.46% (v/v) to 5.93% (v/v), while the highest alcohol amount was obtained using a pure culture of S. cerevisiae. The major volatiles among beer aroma compounds was acetaldehyde, n-propanol, 3-methyl-butanol, 2-methyl-butanol, ethyl acetate, isoamyl acetate, 2,3-butanedione, and 2,3-pentanedione. It was ascertained that the total amount of higher alcohols was higher in the S. cerevisiae control beer compared to all mixed fermentations. Total ester levels were higher in all the mixed culture beers than the control beer. Sensory evaluation showed that all the mixed cultures of S. cerevisiae and T. delbrueckii positively influenced the sensory profile of the beers. Strain Y1031 was the most preferred and was characterized as rich in hop aroma and full bodied. It is therefore a suitable strategy to use T. delbrueckii in mixed fermentations with S. cerevisiae to produce beer with a distinctive flavor. The results demonstrate that, T. delbrueckii strains isolated or commercialized for winemaking can be equally employed as well in brewing. In the present study, the use of five differentTorulaspora delbrueckii strains was evaluated for beer production, in mixed cultures with a Saccharomyces cerevisiae starter strain. [ABSTRACT FROM AUTHOR]

Non-conventional yeasts can be isolated from a wide range of environmental sources and are often found in the beverage industry in mixed fermentations, in which the microbial community is usually not fully known. However, it is important to know the compositions of these starter cultures because in addition to enabling reproducibility during fermentation, other properties can be discovered. Thus, the objective of this work was to identify and characterize non-conventional yeasts isolated from the environment, evaluating their probiotic potential and possible use in beer brewing. Isolates were obtained from flowers, fruits, leaves and mixed-fermentation beers, with the species being identified by PCR. Yeasts with promising activity were evaluated regarding their growth under different pHs, temperature and the presence of organic acids. To explore probiotic potential, in vitro tests were performed for antimicrobial activity and co-aggregation with food-spoiling microorganisms, auto-aggregation and survival in simulated gastrointestinal tract conditions. In this study, Pichia kluyveri (LAR001), Hanseniaspora uvarum (PIT001) and Candida intermedia (ORQ001) were selected among 20 isolates for further study. P. kluyveri was the only strain that tolerated pH 2.5. Lactic acid was not inhibitory, but acetic acid and incubation at 37 °C had partially inhibitory effects on yeast growth. All yeasts tolerated α-acids from hops and up to 1% NaCl. Our results also suggest that these isolates are able to adhere to intestinal cells and positively influence the host to combat pathogens, as they showed auto-aggregation rates > 99% and antagonistic activity to pathogenic bacteria. The yeasts tolerated gastric environment conditions, but were more sensitive to pancreatic conditions. We conclude that these non-conventional yeasts have probiotic potential and promising application in beer fermentation. [ABSTRACT FROM AUTHOR]