Effects of fermentation temperature on the strain population of Saccharomyces cerevisiae

Diacetyl and 2,3-pentanedione are important constituents of beer sensory properties. A new GC/MS method for diacetyl and 2,3-pentanedione content determination was developed. This method was applied for the determination of diacetyl and 2,3-pentanedione contents during beer fermentation (primary fermentation and maturation). Primary fermentations were carried out at different temperatures (8?C and 14?C). Primary fermentation temperature had a great influence on diacetyl and 2,3-pentanedione formation and reduction. Formation and reduction rates increased with the primary fermentation temperature increasment. Diacetyl and 2,3-pentanedione contents also increased with the corn grits increasment. Fermentations were carried out with Saccharomyces cerevisiae pure culture, specially prepared for each fermentation. This GC/MS method for diacetyl and 2,3-pentanedione determination was valuable for analysing the influence of wort composition or fermentation conditions such as primary fermentation temperature on their formation and reduction.

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Fermentation Temperature Modulates Phosphatidylethanolamine and Phosphatidylinositol Levels in the Cell Membrane of Saccharomyces cerevisiae

Applied and Environmental Microbiology ◽

10.1128/aem.01144-13 ◽

2013 ◽

Vol 79 (17) ◽

pp. 5345-5356 ◽

Cited By ~ 27

Author(s):

Clark M. Henderson ◽

Wade F. Zeno ◽

Larry A. Lerno ◽

Marjorie L. Longo ◽

David E. Block

Keyword(s):

Saccharomyces Cerevisiae ◽

Cell Membrane ◽

Lipid Composition ◽

Yeast Strain ◽

Dependent Manner ◽

Temperature Dependent ◽

Content Type ◽

Fermentation Temperature ◽

Yeast Strains ◽

Cell Membrane Fluidity

ABSTRACTDuring alcoholic fermentation,Saccharomyces cerevisiaeis exposed to a host of environmental and physiological stresses. Extremes of fermentation temperature have previously been demonstrated to induce fermentation arrest under growth conditions that would otherwise result in complete sugar utilization at “normal” temperatures and nutrient levels. Fermentations were carried out at 15°C, 25°C, and 35°C in a defined high-sugar medium using threeSaccharomyces cerevisiaestrains with diverse fermentation characteristics. The lipid composition of these strains was analyzed at two fermentation stages, when ethanol levels were low early in stationary phase and in late stationary phase at high ethanol concentrations. Several lipids exhibited dramatic differences in membrane concentration in a temperature-dependent manner. Principal component analysis (PCA) was used as a tool to elucidate correlations between specific lipid species and fermentation temperature for each yeast strain. Fermentations carried out at 35°C exhibited very high concentrations of several phosphatidylinositol species, whereas at 15°C these yeast strains exhibited higher levels of phosphatidylethanolamine and phosphatidylcholine species with medium-chain fatty acids. Furthermore, membrane concentrations of ergosterol were highest in the yeast strain that experienced stuck fermentations at all three temperatures. Fluorescence anisotropy measurements of yeast cell membrane fluidity during fermentation were carried out using the lipophilic fluorophore diphenylhexatriene. These measurements demonstrate that the changes in the lipid composition of these yeast strains across the range of fermentation temperatures used in this study did not significantly affect cell membrane fluidity. However, the results from this study indicate that fermentingS. cerevisiaemodulates its membrane lipid composition in a temperature-dependent manner.

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Effects of low temperature-adapted Saccharomyces cerevisiae Y297 strain and fermentation temperature on the quality characteristics of Yakju

Korean Journal of Food Preservation ◽

10.11002/kjfp.2016.23.5.666 ◽

2016 ◽

Vol 23 (5) ◽

pp. 666-672 ◽

Cited By ~ 1

Author(s):

Dong-Jun Seo ◽

Soo-Hwan Yeo ◽

Ji-Young Mun ◽

Seong Yeol Baek

Keyword(s):

Saccharomyces Cerevisiae ◽

Low Temperature ◽

Quality Characteristics ◽

Fermentation Temperature

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Norwegian Kveik brewing yeasts are adapted to higher temperatures and produce fewer off-flavours under heat stress than commercial Saccharomyces cerevisiae American Ale yeast

10.1101/2021.06.15.448505 ◽

2021 ◽

Author(s):

Dimitri Kits ◽

Lars Marius Garshol

Keyword(s):

Saccharomyces Cerevisiae ◽

Elevated Temperatures ◽

Active Metabolites ◽

Fermentation Temperature ◽

Fusel Alcohols ◽

Western Norway ◽

Apparent Attenuation ◽

Brewer’S Yeasts ◽

Fine Tune ◽

Brewing Yeasts

Norwegian kveik are a recently described family of domesticated Saccharomyces cerevisiae brewing yeasts used by farmhouse brewers in western Norway for generations to produce traditional Norwegian farmhouse ale. Kveik ale yeasts have been domesticated by farmhouse brewers through serial repitching of the yeast in warm wort (>30°C) punctuated by long periods of dry storage. Kveik yeasts are alcohol tolerant, flocculant, capable of utilizing maltose/maltotriose, phenolic off flavour negative, and exhibit elevated thermotolerance when compared to other modern brewer's yeasts belonging to the 'Beer 1' clade. However, the optimal fermentation and growth temperatures (Topt) for kveik ale yeasts and the influence of fermentation temperature of the production of flavour-active metabolites like fusel alcohols and sulfur compounds (H2S, SO2) are not known. Here we show that kveik ale yeasts have an elevated optimal fermentation temperature (Topt) when compared to commercial American Ale yeast (SafAle™ US-05) and that they produce fewer off-flavours at high temperatures (>30°C) when compared to commercial American Ale yeasts. The tested kveik yeasts show significantly higher maximum fermentation rates than American Ale yeast not only at elevated temperatures (>30°C), but also at 'typical' ale fermentation temperatures (20°C-25°C). Finally, we demonstrate that kveik ale yeasts are heterogeneous in their Topt and that they attenuate standard wort robustly above their Topt unlike our control American Ale yeast which showed very poor apparent attenuation in our standard wort at temperatures >> Topt. Our results provide further support that kveik yeasts may possess favourable fermentation kinetics and sensory properties compared to American Ale yeasts. The observations here provide a roadmap for brewers to fine tune their commercial fermentations using kveik ale yeasts for optimal performance and/or flavour impact.

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METHODS OF DETERMINATION OF PARAMETERS OF FERMENTED WHEY-MALTY MIXTURES

EUREKA Life Sciences ◽

10.21303/2504-5695.2018.00710 ◽

2018 ◽

Vol 5 ◽

pp. 30-38

Author(s):

Sergii Tsygankov ◽

Viktor Ushkarenko ◽

Olena Grek ◽

Olena Krasulya ◽

Iuliia Ushkarenko ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Production Systems ◽

Kluyveromyces Lactis ◽

Objective Assessment ◽

Yeast Cells ◽

Generative Capacity ◽

Fermentation Products ◽

Nutritive Medium ◽

Fermentation Temperature ◽

Determination Of Parameters

The article presents main methods of studying restored whey-malty mixtures after fermentation by lactose-fermenting yeast and saccharomyces for getting a beverage of the kvass type. The methods of accumulation of yeast cells Kluyveromyces lactis 469 and their percent with glycogen from the general concentration at fermentation of wort of the restored mixture at different ratios of dry malt and whey are offered and results are obtained. According to the obtained data, it was established, that yeast cells actively developed in the period from 4 to 16 fermentation hour at the ratio of malt and whey in the restored mixture as 1:1,5 and 1:2. The increment of cells with glycogen in mixtures with the ratio – malt:whey as 1,5:1 and 2:1 was intensive. Thus, at 36 hour of fermentation the amount of yeast was 67,2 and 68,9 % respectively from the total number of cells. The generative capacity of yeast allowed to specify the fermentation temperature of wort of restored mixtures, cultivated by different races. It was established, that for Kluyveromyces lactis 469 the maximal accumulation of yeast (67…69 mln cell/cm3 of wort) is observed at fermentation temperature – 30…32 °С, for Saccharomyces cerevisiae Р-87 and Saccharomyces cerevisiae M-5 – 30…34 °С. The gasochromatographic method allowed to identify side products of fermentation of fermented whey-malty wort by both lactose fermenting yeast and saccharomyces. The presented information is enough for the objective assessment of the qualitative composition of fermentation products as a result of the effect of different yeast races. The use of Saccharomyces cerevisiae Р-87 for fermentation of whey-malty wort positively influences metabolism of a producer, stimulating biosynthesis or transformation of aromatic substances of the nutritive medium. The obtained research results indicate objective possibilities for the effective functioning of the aforesaid yeast race for fermentation of restored whey-malty wort in production systems.

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