The influence of Lyophilization conditions on Yeast vitality and Fermentation activity.

Abstract

The aim of this reserach was to consider the influence of the age of yeast culture on their survival after lyophilization and in the process of further storage. Two-, three-, seven- and thirtheen-day-old cultures were used for lyophilization, which were grown in tubes on shira-agar. Properly performed lyophilization significantly affects the survival and fermentation activity of yeasts. Three-day-old yeast cultures are most vital during lyophilization. Yeasts survive best in protective media containing 10% sucrose, 1% gelatin, 0.1% agar-agar and 2% CaCO3, or 10% skim milk and 1% sodium glutamate. Prolonged storage in the dried state and rehydration lead to decreasing in reproductive energy and fermentation activity of yeasts.