Note: Characterization of Yeast Strains on the Basis of Autolytic Activity and Volatile Compounds

Abstract

Autolytic activity and the production of several major volatile compounds were studied for a set of 18 commercial and non-commercial Saccharomyces cerevisiæ strains isolated from sparkling wine, cider and sherry fermentations. No correlation was found between the autolytic capacity of the strains and isobutanol production levels, in contrast with results published by other authors for a limited number of S. cerevisiæ strains. The 18 strains were classified in three groups by cluster analysis; the variables that best discriminated the groups were related with autolysis, with a limited effect of the volatile compounds. All the commercial sparkling wine second fermentation strains appeared in the same group, which was characterized by the release of high amounts of proteins under conditions of accelerated autolysis. This could probably be explained by an indirect selection for efficient autolysis for these commercial strains. Most sherry and cider isolates appeared in a single group. Interestingly, one strain isolated from cider fermentation is grouped with sparkling wine commercial strains.