THE SYNTHESIS OF CARBONYL COMPOUNDS FROM SACCHAROMYCES CEREVISIAE STRAINS IN CABERNET SAUVIGNON WINES

The ability of two Saccharomyces cerevisiae strains (Bordeaux, 8-11) to produce carbonyl compounds under different conditions of the alcoholic fermentation was investigated. The impact of the temperature and the inoculum yeast culture ratio on the synthesis of total aldehydes during the process was traced. A more pronounced effect of the temperature was observed. At the beginning of the fermentation, the total aldehydes rate increased rapidly and reached a maximum during the exponential phase of the yeast cells development (day 5th), thereafter their amount began to go down. The strain Saccharomyces cerevisiae Bordeaux synthesized the most total aldehydes at a temperature of 24оС, while Saccharomyces cerevisiae 8-11 - at 28оС. Acetaldehyde, acetone and 2-butanone were identified in the experimental wines by gas chromatographic analysis. During the fermentation at a temperature of 20°C and 24°C, Saccharomyces cerevisiae Bordeaux produced more acetaldehyde, acetone and 2-butanone compared to 8-11. At 28°C Saccharomyces cerevisiae 8-11 produced more acetaldehyde and 2-butanone, 33.3% and 15% respectively, and 30% less acetone than Saccharomyces cerevisiae Bordeaux. The total aldehydes rate in the experimental samples did not have a negative effect on their aromatic and taste qualities.