EVOLUTION OF C-6, C-8 AND C-10 ACIDS AND THEIR ETHYL-ESTERS IN CELLS AND MUSTS DURING FERMENTATION WITH 3 SACCHAROMYCES-CEREVISIAE RACES

The evolution of the cell and must contents of three short-chain fatty acids (C-6, C-8 and C-10) and their ethyl esters during fermentations with Saccharomyces cerevisiae races cerevisiae, bayanus and capensis were studied. The former is a fermentative yeast and the last two are 'flor' film yeasts. The acid concentrations in the musts increased throughout the alcoholic fermentations, and maximum cell concentrations of the fatty acids were reached after 48 h of fermentation. Maximum ester concentrations in the cells were attained after 48-72 h of fermentation. In the musts, ethyl octanoate and ethyl decanoate reached a peak also at this point, and ethyl hexanoate after 10 days. After 134 days, S. cerevisiae race capensis formed a thick 'flor' film while S. cerevisiae race bayanus developed a thin film and S. cerevisiae race cerevisiae formed no film. At this point, acid contents remained constant in the wines produced by S. cerevisiae races cerevisiae and bayanus, and decreased in those obtained with race capensis. The ethyl ester contents tended to decrease with the exception of ethyl decanoate in the fermentations carried out by S. cerevisiae races cerevisiae and bayanus.