Premium
Osmoadaptation of wine yeast ( Saccharomyces cerevisiae ) during Icewine fermentation leads to high levels of acetic acid
Author(s) -
Heit C.,
Martin S.J.,
Yang F.,
Inglis D.L.
Publication year - 2018
Publication title -
journal of applied microbiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.889
H-Index - 156
eISSN - 1365-2672
pISSN - 1364-5072
DOI - 10.1111/jam.13733
Subject(s) - fermentation , acetic acid , yeast , saccharomyces cerevisiae , biochemistry , wine , ethyl acetate , fermentation in winemaking , food science , yeast in winemaking , biology , gene expression , chemistry , gene
Aims Volatile acidity (VA) production along with gene expression patterns, encoding enzymes involved in both acetic acid production and utilization, were investigated to relate gene expression patterns to the production of undesired VA during Icewine fermentation. Methods and Results Icewine juice and diluted Icewine juice were fermented using the Saccharomyces cerevisiae wine yeast K1‐V1116. Acetic acid production increased sixfold during the Icewine fermentation vs the diluted juice condition, while ethyl acetate production increased 2·4‐fold in the diluted fermentation relative to the Icewine. Microarray analysis profiled the transcriptional response of K1‐V1116 under both conditions. ACS 1 and ACS 2 were downregulated 19·0‐fold and 11·2‐fold, respectively, in cells fermenting Icewine juice compared to diluted juice. ALD 3 expression was upregulated 14·6‐fold, and gene expressions involved in lipid and ergosterol synthesis decreased during Icewine fermentation. Conclusions Decreased expression of ACS 1 and ACS 2 together with increased ALD 3 expression contributes to the higher acetic acid and lower ethyl acetate levels generated by K1‐V1116 fermenting under hyperosmotic stress. Significance and Impact of the Study This work represents a more comprehensive understanding of how and why commercial wine yeast respond at the transcriptional and metabolic level during fermentation of Icewine juice, and how these responses contribute to increased acetic acid and decreased ethyl acetate production.