Co-inoculation of different Saccharomyces cerevisiae strains and influence on volatile composition of wines.

Wine is the result of the performance of different yeast strains throughout the fermentation in both spontaneous and inoculated processes. 22 Saccharomyces cerevisiae strains were characterized by microsatellite fingerprinting, selecting 6 of them to formulate S. cerevisiae mixed cultures. The aim of this study was to ascertain a potential benefit to use mixed cultures to improve wine quality. For this purpose yeasts behavior was studied during co-inoculated fermentations. Aromatic composition of the wines obtained was analyzed, and despite the fact that only one strain dominated at the end of the process, co-cultures released different concentrations of major volatile compounds than single strains, especially higher alcohols and acetaldehydes. Nevertheless, no significant differences were found in the type and quantity of the amino acids assimilated. This study demonstrates that the final wine composition may be modulated and enhanced by using suitable combinations of yeast strains.