Study of the effectiveness of a strain ofSaccharomyces cerevisiaeselected for the production of wines with higher acidity and lower alcoholic strength

Abstract

Grapes of Tempranillo, Garnacha Tinta and Merlot at very high maturity level were used for red microvinifications using a conventional Saccharomyces cerevisiae strain (Lalvin EC 1118 R) and new S. cerevisiae strain generated using adaptive evolution-based strategies (IONYS TM WF). All microvinifications were performed by triplicate and at low (16 • C) and at high (27 • C) temperatures. The results show that all the wines fermented with IONYS TM WF, independently of the fermentation temperature and grape cultivar have significant lower ethanol content (average 0.60 %), higher glycerol content (average of 5.6 g/L), higher titratable acidity (average of 1.3 g of tartaric acid/L) and lower pH (average of 0.1 units) than their corresponding controls. It seems therefore that IONYS TM WF strain can be a useful tool to mitigate the excess of ethanol and the lack of acidity that unfortunately many wines present nowadays. Moreover, the high glycerol production can also be an interesting contribution inasmuch as this compound increases mouthfeel and smooth astringency.

Influence of Nutrient Supplementation on Torulaspora Delbrueckii Wine Fermentation Aroma

“…The ethanol yield can be considered to compare the fermentative power among the strains tested in this trial. A transformation ratio of 16.83 g/L of sugar for 1% v/v of ethanol for S. cerevisiae [39,40] is generally accepted. This means that a normal ethanol yield would be approximately 0.48 g/g, while the values obtained in this trial ranged from 0.40 to 0.44 g/g (Table 1).…”