Fermentation Activity of Yeast in Pinot Noir Must

Abstract

This study presents the effect of some B vitamins and mineral nitrogen on yeast growth rate and the rate of the alcoholic fermentation of wine must, as well as on the amount of some wine components produced as by-products of the alcoholic fermentation of sugar. Thiamine, pantothenic acid and pyridoxine were added to the pasteurised sulphured must both as a sterile solution, each at a concentration of 1mg/l, and as a mixture. Secondary ammonium phosphate was added at a concentration of 0.8gl(-1) of must. The experiment showed that the addition of thiamine, the vitamin mixture and ammonium phosphate stimulated yeast growth and the course of the alcoholic fermentation of must, leading to an increased production of glycerine and volatile acids in the wine produced, whereas the supplementation with pantothenic acid and pyridoxine did not substantially enhance wine yeast growth, the fermentation process and the amount of must by-products.