[Effect of carbon composition of the fermented medium on the synthesis of volatile acids by the yeast Saccharomyces carlsbergensis 776].

Abstract

The effect of glucose, maltose and sucrose on the synthesis of volatile oils during fermentation of model carbohydrate solutions (6, 8 and 11%) by the yeast Saccharomyces carlsbergensis 776 was studied. The composition and concentration of carbohydrates affected the build-up of volatile fatty acids during fermentation. The accumulation of biomass and volatile fraction of fatty acids reached maximum on the medium containing 11% glucose. There was a certain correlation between the biomass synthesis and accumulation of volatile fatty acids, i.e. with an increase in the biomass the content of volatile fatty acids in the medium increased. During fermentation of disaccharide solutions cell multiplication diminished and the fermentation process accelerated. Ethanol, residual sugar and acidity of fermented solutions increased with the initial concentration of carbohydrates. The pH value of the fermented must remained essentially unaltered independent of the sugar amount used.