Low Temperature Alcoholic Fermentations in High Sugar Concentration Grape Musts

Low temperature fermentations can increase the quality of wine produced from some aromatic grape varieties. However, these fermentations in musts with a high sugar content may have limitations. The fermentation kinetics and the composition of the resulting wines of 5 different musts have been compared. Maximum fermentation rates correlated well with the available nitrogen. The correlation between the available nitrogen and fermentation rates improved if selected amino acids are corrected for the total sugar content. We propose this new nitrogen parameter as a way of predicting fermentation rates. Must fermentations at low temperatures yielded wines with lower levels of acetic acid, acetaldehyde and ethyl acetate, which can be considered to be positive.