Study of the effectiveness of a strain of Saccharomyces cerevisiae selected for the production of wines with higher acidity and lower alcoholic strength

¹ Departamento de Bioquímica y Biotecnología, Facultad de Enología de Tarragona, Universidad Rovira i Virgili, C/ Marcel.lí Domingo, 1, 43007 Tarragona, España
² Lallemand Bio S.L. C/ Galileu 303, 1 a planta, 08028-Barcelona, España

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®) and new S. cerevisiae strain generated using adaptive evolution-based strategies (IONYS^™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^™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^™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.