In this work we monitored the influence of fermentation temperature on the course of alcoholic fermentation of white must, using two different strains of wine yeast as starter cultures. The experiment was performed in two duplicates: two grape must samples and the control sample were incubated at 20 °C and the other two must samples at 10 °C. We monitored the course of alcoholic fermentation gravimetrically - how much carbon dioxide was released over a certain period of time. From these data, we calculated how much sugar the yeast cells had already fermented into ethanol and carbon dioxide, and at the same time we got the graphs of the fermentation curve and fermentation kinetics. The fermentation kinetics varied considerably between the duplicates. The warm specimens quickly reached the highest released carbon dioxide concentration while the cold specimens fermented slowly. After the alcoholic fermentation was completed, we put the samples of the produced wines for analysis, as we were interested in the differences in the chemical composition of the wines fermented at different temperatures. We concluded that the temperature of alcoholic fermentation was too low by 10 °C and even after moving the fermentation bottles to a warmer place, the must fermented for too long (36 days). However, there are no signicifant differences in chemical composition between the wine duplicates.
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