THE STRATEGY OF EFFICIENT PRODUCTION OF BREWERS-YEAST BIOMASS

The effect of preaeration, addition of unsaturated fatty acids and the most important fermentation parameters - sugar concentration and aeration level on brewer's yeast production - was investigated in synthetic and malt germ medium. Increased aeration level (500 lh-1) has a beneficial effect on growth rate, but the lower intensity resulted in higher protein content. Yeast growth at different maltose concentrations underline the effect of glucose on brewer's yeast, causing catabolite repression of the respiratory enzymes. Supplementation of fermentation broth with linseed oil caused a drastic decrease in lag period. The unsaturated oil is co-utilized which results in a higher growth rate at 0.5% linseed oil concentration. Preaeration of the inoculum is also effective in the reduction of lag period without any effect on the growth rate.