酿酒酵母DCCS101脱除荔枝酒挥发醋酸的效果研究

以酿酒酵母DCCS101为出发菌株,研究其在不同条件下脱除挥发醋酸的效果。结果表明：以新鲜的荔枝汁作为发酵基质,酿酒酵母脱除外源醋酸的能力最大可达45%,但外源醋酸浓度高达2 g/L时,发酵终了醋酸浓度仍然达不到荔枝酒挥发酸最低标准的要求;酿酒酵母DCCS101脱除醋酸的速度与酵母生长繁殖速度有关。在以新鲜荔枝汁作为发酵基质的情况下,酵母生长繁殖指数期时脱除醋酸的速度最快;用新鲜荔枝汁调整荔枝酸酒作为发酵基质,在低糖高酒精度增氧条件下醋酸脱除率高达86.3%;以荔枝酸酒直接作为发酵基质,酿酒酵母DCCS101在增氧条件下能较好地生长繁殖,并将起始醋酸浓度1.5 g/L降低至0.53 g/L的水平,有效地提高了荔枝酒的品质。

Effects of Acetic Acid Removal of Lichi Wine by Saccharomyces cerevisiae strain DCCS101

The Saccharomyces cerevisiae strain DCCS101 was tested for its ability to metabolize volatile acetic acid under different conditions.The results showed when fresh litchi juice was added with acetic acid as fermentation matrix,the consumption of exogenous acetic acid was close to 45%.When acetic acid was added at 2 g/L,its elimination during fermentation was not sufficient to reach an acceptable level in the resulting lichi wine according to the current legislation.The removal rate of acetic acid of S.cerevisiae strain DCCS101 was related to its growth speed.When yeast growth at exponential phase,the speed of acetic acid consumption was fastest.When the acidic lichi wine was added with fresh litchi juice containing low sugar and high ethanol as fermentation matrix,the removal rate of acetic acid was up to 86.3%.When the acidic lichi wine was used as fermentation matrix under aerobic conditions,initial acetic acid concentration could be reduced from 1.5 g/L to 0.53 g/L,and litchi wine quality was improved effectively.