A Rapid Method for Selecting Non-Saccharomyces Strains with a Low Ethanol Yield

The alcohol content in wine has increased due to external factors in recent decades. In recent reports, some non-Saccharomyces yeast species have been confirmed to reduce ethanol during the alcoholic fermentation process. Thus, an efficient screening of non-Saccharomyces yeasts with low ethanol yield is required due to the broad diversity of these yeasts. In this study, we proposed a rapid method for selecting strains with a low ethanol yield from forty-five non-Saccharomyces yeasts belonging to eighteen species. Single fermentations were carried out for this rapid selection. Then, sequential fermentations in synthetic and natural must were conducted with the selected strains to confirm their capacity to reduce ethanol compared with that of Saccharomyces cerevisiae. The results showed that ten non-Saccharomyces strains were able to reduce the ethanol content, namely, Hanseniaspora uvarum (2), Issatchenkia terricola (1), Metschnikowia pulcherrima (2), Lachancea thermotolerans (1), Saccharomycodes ludwigii (1), Torulaspora delbrueckii (2), and Zygosaccharomyces bailii (1). Compared with S. cerevisiae, the ethanol reduction of the selected strains ranged from 0.29 to 1.39% (v/v). Sequential inoculations of M. pulcherrima (Mp51 and Mp FA) and S. cerevisiae reduced the highest concentration of ethanol by 1.17 to 1.39% (v/v) in synthetic or natural must. Second, sequential fermentations with Z. bailii (Zb43) and T. delbrueckii (Td Pt) performed in natural must yielded ethanol reductions of 1.02 and 0.84% (v/v), respectively.

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Aromatic Potential of Diverse Non-Conventional Yeast Species for Winemaking and Brewing

Fermentation ◽

10.3390/fermentation6020050 ◽

2020 ◽

Vol 6 (2) ◽

pp. 50

Author(s):

Amparo Gamero ◽

Annereinou Dijkstra ◽

Bart Smit ◽

Catrienus de Jong

Keyword(s):

Screening Tool ◽

Yeast Species ◽

Scaling Up ◽

Screening Tools ◽

Alcoholic Beverages ◽

Acetate Ester ◽

Ester Yield ◽

Efficient Screening ◽

Craft Beers ◽

Saccharomyces Yeasts

Traditionally, Saccharomyces species are those used to conduct industrial alcoholic fermentations. Recently, an increasing interest has arisen with respect to the potential of so-called non-conventional yeasts to improve wine and beer aroma profiles, keeping the particular terroir of each region or for the development of craft beers. In this study, the potential of diverse non-conventional yeasts to improve aroma in winemaking and brewing was investigated, testing several pure and mixed culture combinations. In addition, a comparison between microscale and labscale was carried out in order to assess the value of microwine and microbeer as screening tools. The results indicated that non-Saccharomyces yeasts were good candidates to enhance or diversify aroma profiles in alcoholic beverages, especially regarding acetate ester yield and fruity aromas. However, mixed cultures with Saccharomyces spp. are normally required to achieve a successful fermentation. The adjustment of pithing ratios is crucial for this purpose. Microscale is presented as an effective and efficient screening tool to compare different culture combinations, although scaling-up will always be necessary in order to get results closer to real winemaking or brewing processes.

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Application of Non-Saccharomyces Yeasts Isolated from Kombucha in the Production of Alcohol-Free Beer

Fermentation ◽

10.3390/fermentation4030066 ◽

2018 ◽

Vol 4 (3) ◽

pp. 66 ◽

Cited By ~ 12

Author(s):

Konstantin Bellut ◽

Maximilian Michel ◽

Martin Zarnkow ◽

Mathias Hutzler ◽

Fritz Jacob ◽

...

Keyword(s):

Product Category ◽

Economic Benefits ◽

Product Portfolio ◽

Zygosaccharomyces Bailii ◽

Ethanol Formation ◽

Off Flavors ◽

Saccharomycodes Ludwigii ◽

The One ◽

By Products ◽

Saccharomyces Yeasts

Alcohol-free beer (AFB) is no longer just a niche product in the beer market. For brewers, this product category offers economic benefits in the form of a growing market and often a lower tax burden and enables brewers to extend their product portfolio and promote responsible drinking. Non-Saccharomyces yeasts are known for their flavor-enhancing properties in food fermentations, and their prevailing inability to ferment maltose and maltotriose sets a natural fermentation limit and can introduce a promising approach in the production of AFB (≤0.5% v/v). Five strains isolated from kombucha, Hanseniaspora valbyensis, Hanseniaspora vineae, Torulaspora delbrueckii, Zygosaccharomyces bailii and Zygosaccharomyces kombuchaensis were compared to a commercially applied AFB strain Saccharomycodes ludwigii and a Saccharomyces cerevisiae brewer’s yeast. The strains were characterized for their sugar utilization, phenolic off-flavors, hop sensitivity and flocculation. Trial fermentations were analyzed for extract reduction, ethanol formation, pH drop and final beers were analyzed for amino acids utilization and fermentation by-products. The performance of non-Saccharomyces strains and the commercial AFB strain were comparable during fermentation and production of fermentation by-products. An experienced sensory panel could not discriminate between the non-Saccharomyces AFB and the one produced with the commercial AFB strain, therefore indicating their suitability in AFB brewing.

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Effect of a Multistarter Yeast Inoculum on Ethanol Reduction and Population Dynamics in Wine Fermentation

Foods ◽

10.3390/foods10030623 ◽

2021 ◽

Vol 10 (3) ◽

pp. 623

Author(s):

Xiaolin Zhu ◽

María-Jesús Torija ◽

Albert Mas ◽

Gemma Beltran ◽

Yurena Navarro

Keyword(s):

Culture Medium ◽

Yeast Species ◽

Microbial Populations ◽

Inoculum Concentration ◽

Zygosaccharomyces Bailii ◽

Culture Independent ◽

Saccharomyces Yeast ◽

Yeast Inoculum ◽

Saccharomyces Yeasts ◽

Acetic Acids

Microbiological strategies are currently being considered as methods for reducing the ethanol content of wine. Fermentations started with a multistarter of three non-Saccharomyces yeasts (Metschnikowia pulcherrima (Mp), Torulaspora delbrueckii (Td) and Zygosaccharomyces bailii (Zb)) at different inoculum concentrations. S. cerevisiae (Sc) was inoculated into fermentations at 0 h (coinoculation), 48 h or 72 h (sequential fermentations). The microbial populations were analyzed by a culture-dependent approach (Wallerstein Laboratory Nutrient (WLN) culture medium) and a culture-independent method (PMA-qPCR). The results showed that among these three non-Saccharomyces yeasts, Td became the dominant non-Saccharomyces yeast in all fermentations, and Mp was the minority yeast. Sc was able to grow in all fermentations where it was involved, being the dominant yeast at the end of fermentation. We obtained a significant ethanol reduction of 0.48 to 0.77% (v/v) in sequential fermentations, with increased concentrations of lactic and acetic acids. The highest reduction was achieved when the inoculum concentration of non-Saccharomyces yeast was 10 times higher (107 cells/mL) than that of S. cerevisiae. However, this reduction was lower than that obtained when these strains were used as single non-Saccharomyces species in the starter, indicating that interactions between them affected their performance. Therefore, more combinations of yeast species should be tested to achieve greater ethanol reductions.

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Isolation and Identification of Indigenous Wine Yeasts and their Use in Alcoholic Fermentation

Food Technology and Biotechnology ◽

10.17113/ftb.58.03.20.6677 ◽

2020 ◽

Vol 58 (3) ◽

pp. 337-347

Author(s):

Polona Zabukovec ◽

Neža Čadež ◽

Franc Čuš

Keyword(s):

Alcoholic Fermentation ◽

Promising Result ◽

Isolation And Identification ◽

Pichia Kudriavzevii ◽

Hanseniaspora Uvarum ◽

Volatile Thiols ◽

Indigenous Yeasts ◽

Positive Properties ◽

Potential Use ◽

Saccharomyces Yeasts

Research background. In our study, spontaneous alcoholic fermentations were carried out to isolate non-Saccharomyces and Saccharomyces yeasts from grape must from different wine growing regions in Slovenia. Additionally, the diversity of native Saccharomyces cerevisiae strains was evaluated during the process. Experimental approach. During spontaneous alcoholic fermentations the yeast population of non-Saccharomyces and Saccharomyces yeasts was sampled. We used eleven microsatellite markers to determine the genetic diversity of S. cerevisiae strains. In addition, different proportions of the indigenous strains of S. cerevisiae, Hanseniaspora uvarum and Starmerella bacillaris were tested for their possible use in inoculated AF by monitoring the course of alcoholic fermentation and measuring the content of aroma compounds in wine. Results and conclusions. Sequencing of the ITS regions of ribosomal DNA showed that of 64 isolates 46 strains represent S. cerevisiae and 18 strains belong to non-Saccharomyces yeasts. The identified non-Saccharomyces yeast species were H. uvarum, Pichia kudriavzevii, Saturnispora diversa and S. bacillaris. The dendrogram grouped S. cerevisiae strains into 14 groups. The number of S. cervisiae strains isolated from the musts was 10 (Posavje), 11 (Podravje) and 25 (Primorska vine-growing region). On the other hand, the inoculated AF, in which the native S. cerevisiae strain predominated over H. uvarum and S. bacillaris, gave the most promising result due to the highest alcohol content, the lowest acetic acid concentration and the significantly higher concentrations of volatile thiols (3MHA and 3MH), 2-methylpropanol, 2-methylbutanol, 3-methylbutanol and 2-phenyl ethanol in the wine produced. Novelty and scientific contribution. We confirmed the potential use of indigenous S. cerevisiae and non-Saccharomyces yeasts in inoculated AFs, which allows the positive properties of the yeast strains to be expressed and good quality wines to be produced. Thus, the results are encouraging for winemakers to create different wine styles associated with a particular terroir using indigenous yeasts.

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Spontaneous fermentation in wine production as a controllable technology

Potravinarstvo Slovak Journal of Food Sciences ◽

10.5219/1280 ◽

2020 ◽

Vol 14 ◽

pp. 692-703

Author(s):

Radim Holešinský ◽

Božena Průšová ◽

Mojmír Baroň ◽

Jaromír Fiala ◽

Petra Kubizniakova ◽

...

Keyword(s):

Hydrogen Sulphide ◽

Growth Curves ◽

Spontaneous Fermentation ◽

Wine Production ◽

Zygosaccharomyces Bailii ◽

Hanseniaspora Uvarum ◽

Sulphide Production ◽

Candida Sake ◽

The Given ◽

Saccharomyces Yeasts

This study focuses on the isolation of a consortium of microorganisms from spontaneously fermenting must that naturally contain lactic acid bacteria, non-saccharomyces yeasts, and saccharomyces yeasts. To collect the greatest diversity of microorganisms, the consortium was taken from the point of micro-sparkling. Based on the growth curves, isolation was performed using individual special nutrient media, and the isolates were subsequently multiplied in the nutrient medium. Individual isolates were then used for fermentation tests to monitor the percentage of fermented sugar and hydrogen sulphide production. The highest fermentation abilities were achieved in the isolates containing Saccharomyces cerevisiae and Zygosaccharomyces bailii. The smallest amount of ethanol was formed from the isolates containing Hanseniaspora uvarum, while Candida sake isolate produced the lowest amount of hydrogen sulphide and Zygosaccharomyces bailii produced the highest. The other isolates produced an average amount. Based on these results, a consortium containing the given isolates in a certain ratio was compiled.

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Impact of Hanseniaspora Vineae in Alcoholic Fermentation and Ageing on Lees of High-Quality White Wine

Fermentation ◽

10.3390/fermentation6030066 ◽

2020 ◽

Vol 6 (3) ◽

pp. 66 ◽

Cited By ~ 1

Author(s):

Juan Manuel Del Fresno ◽

Carlos Escott ◽

Iris Loira ◽

José Enrique Herbert-Pucheta ◽

Rémi Schneider ◽

...

Keyword(s):

Alcoholic Fermentation ◽

Yeast Species ◽

White Wine ◽

The Other ◽

High Quality ◽

White Wines ◽

Viable Method ◽

Ageing On Lees ◽

Saccharomyces Yeasts

Hanseniaspora vineae is an apiculate yeast that plays a significant role at the beginning of fermentation, and it has been studied for its application in the improvement of the aromatic profile of commercial wines. This work evaluates the use of H. vineae in alcoholic fermentation compared to Saccharomyces cerevisiae and in ageing on the lees process (AOL) compared to Saccharomyces and non-Saccharomyces yeasts. The results indicated that there were not significant differences in basic oenological parameters. H. vineae completed the fermentation until 11.9% v/v of ethanol and with a residual sugars content of less than 2 g/L. Different aroma profiles were obtained in the wines, with esters concentration around 90 mg/L in H. vineae wines. Regarding the AOL assay, the hydroalcoholic solutions aged with H. vineae lees showed significantly higher absorbance values at 260 (nucleic acids) and 280 nm (proteins) compared to the other strains. However, non-significant differences were found in the polysaccharide content at the end of the ageing process were found compared to the other yeast species, with the exception of Schizosaccharomyces pombe that released around 23.5 mg/L of polysaccharides in hydroalcoholic solution. The use of H. vineae by the wineries may be a viable method in fermentation and AOL to improve the quality of white wines.

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Saccharomyces cerevisiae Fermentation of 28 Barley and 12 Oat Cultivars

Fermentation ◽

10.3390/fermentation7020059 ◽

2021 ◽

Vol 7 (2) ◽

pp. 59

Author(s):

Timothy J. Tse ◽

Daniel J. Wiens ◽

Jianheng Shen ◽

Aaron D. Beattie ◽

Martin J. T. Reaney

Keyword(s):

Saccharomyces Cerevisiae ◽

Acetic Acid ◽

Lactic Acid ◽

Succinic Acid ◽

Alcoholic Fermentation ◽

Ethanol Yield ◽

Cereal Crops ◽

Fermentation Products ◽

Barley Cultivars ◽

Oat Cultivars

As barley and oat production have recently increased in Canada, it has become prudent to investigate these cereal crops as potential feedstocks for alcoholic fermentation. Ethanol and other coproduct yields can vary substantially among fermented feedstocks, which currently consist primarily of wheat and corn. In this study, the liquified mash of milled grains from 28 barley (hulled and hull-less) and 12 oat cultivars were fermented with Saccharomyces cerevisiae to determine concentrations of fermentation products (ethanol, isopropanol, acetic acid, lactic acid, succinic acid, α-glycerylphosphorylcholine (α-GPC), and glycerol). On average, the fermentation of barley produced significantly higher amounts of ethanol, isopropanol, acetic acid, succinic acid, α-GPC, and glycerol than that of oats. The best performing barley cultivars were able to produce up to 78.48 g/L (CDC Clear) ethanol and 1.81 g/L α-GPC (CDC Cowboy). Furthermore, the presence of milled hulls did not impact ethanol yield amongst barley cultivars. Due to its superior ethanol yield compared to oats, barley is a suitable feedstock for ethanol production. In addition, the accumulation of α-GPC could add considerable value to the fermentation of these cereal crops.

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Enzymatic Process for Cystoseira barbata Valorization: Ethanol Production and Additional By-Products

Processes ◽

10.3390/pr9050741 ◽

2021 ◽

Vol 9 (5) ◽

pp. 741

Author(s):

Doinita-Roxana Cioroiu Tirpan ◽

Ancaelena Eliza Sterpu ◽

Claudia Irina Koncsag ◽

Alina Georgiana Ciufu ◽

Tănase Dobre

Keyword(s):

Ethanol Production ◽

Alcoholic Fermentation ◽

Ethanol Yield ◽

Product Yield ◽

Liquid Ratio ◽

Experimental Conditions ◽

Factors Affecting ◽

Cystoseira Barbata ◽

Main Factors ◽

Process Factors

The aim of this study is to evaluate the potential of dried Cystoseira barbata alga for ethanol production through alcoholic fermentation. The influence of the main factors affecting the fermentation are studied in the frame of a 23 factorial experimental plan. The main factors influencing the process are the fermentation temperature (t from 25 °C to 35 °C), the solid to liquid ratio (S/L from 0.040 g/g to 0.080 g/g), and the cellulase ratio (R from 8 U/g d.m to 16 U/g d.m.). The maximum volatile compounds yield of 0.2808 g/g d.m and ethanol yield of 0.0158 g/g d.m were favored by the following experimental conditions: process temperature of 35 °C, solid to liquid ratio of 0.0415, and enzyme ratio of 16 U/g d.m. A statistical model was used to correlate the product yield with the process factors. Additionally, 19 interesting bioactive compounds were found in the enzymatic hydrolysis and alcoholic fermentation broths which seem likely to maintain natural defence mechanisms against diseases and physical disorders.

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Separate and combined Hanseniaspora uvarum and Metschnikowia pulcherrima metabolic volatiles are attractive to Drosophila suzukii in the laboratory and field

Scientific Reports ◽

10.1038/s41598-020-79691-3 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

R. Jones ◽

M. T. Fountain ◽

C. S. Günther ◽

P. E. Eady ◽

M. R. Goddard

Keyword(s):

Yeast Species ◽

Field Trapping ◽

Field Trials ◽

Economic Losses ◽

Drosophila Suzukii ◽

Control Efficacy ◽

Hanseniaspora Uvarum ◽

Metschnikowia Pulcherrima ◽

Rich Diversity ◽

Relative Attractiveness

AbstractDrosophila suzukii flies cause economic losses to fruit crops globally. Previous work shows various Drosophila species are attracted to volatile metabolites produced by individual fruit associated yeast isolates, but fruits naturally harbour a rich diversity of yeast species. Here, we report the relative attractiveness of D. suzukii to yeasts presented individually or in combinations using laboratory preference tests and field trapping data. Laboratory trials revealed four of 12 single yeast isolates were attractive to D. suzukii, of which Metschnikowia pulcherrima and Hanseniaspora uvarum were also attractive in field trials. Four out of 10 yeast combinations involving Candida zemplinina, Pichia pijperi, M. pulcherrima and H. uvarum were attractive in the laboratory. Whilst a combination of M. pulcherrima + H. uvarum trapped the greatest number of D. suzukii in the field, the efficacy of the M. pulcherrima + H. uvarum combination to trap D. suzukii was not significantly greater than traps primed with volatiles from only H. uvarum. While volatiles from isolates of M. pulcherrima and H. uvarum show promise as baits for D. suzukii, further research is needed to ascertain how and why flies are attracted to certain baits to optimise control efficacy.

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Learning from 80 years of studies: a comprehensive catalogue of non-Saccharomyces yeasts associated with viticulture and winemaking

FEMS Yeast Research ◽

10.1093/femsyr/foab017 ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

João Drumonde-Neves ◽

Ticiana Fernandes ◽

Teresa Lima ◽

Célia Pais ◽

Ricardo Franco-Duarte

Keyword(s):

Yeast Species ◽

Starter Cultures ◽

Biotechnological Applications ◽

Major Focus ◽

Wine Production ◽

Sampling Studies ◽

Volatile Acidity ◽

Wine Sector ◽

Saccharomyces Yeast ◽

Saccharomyces Yeasts

ABSTRACT Non-Saccharomyces yeast species are nowadays recognized for their impact on wine´s chemical composition and sensorial properties. In addition, new interest has been given to the commercial exploitation of non-Saccharomyces starter cultures in the wine sector. However, over many years, these yeast species were considered sources of contamination in wine production and conservation, mainly due to the high levels of volatile acidity obtained. The present manuscript systematizes 80 years of literature describing non-Saccharomyces yeast species isolated from grapes and/or grape musts. A link between each reference, the accepted taxonomic name of each species and their geographical occurrence is presented, compiling information for 293 species, in a total of 231 citations. One major focus of this work relates to the isolation of non-Saccharomyces yeasts from grapevines usually ignored in most sampling studies, also as isolation from damaged grapes. These particular niches are sources of specific yeast species, which are not identified in most other explored environments. These yeasts have high potential to be explored for important and diversified biotechnological applications.

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