In this study, the fermenting performance of yeast strain R2 and DV10 inoculating with litchi juice at low temperature (12℃) and high sugar concentration (340 g/L) was investigated. Ammonium sulfate was added to supplement the fermenting nitrogen source to settle the problem of slow yeast fermentation under high osmotic pressure, and the change rule of total sugar, alcohol content and higher alcohol content in the fermenting process were investigated. The results showed that, the addition of ammonium sulfate could obviously promote sugar con-sumption, increase ethanol and ester content, and reduce the yield of higher alcohols and volatile acids. For example, higher alcohol content in litchi juice fermented by strain R2 with the addition of ammonium sulfate at 20 d, 25 d and 30 d decreased by 37.52%,22.42%and 22.40%re-spectively than the control group;higher alcohol content in litchi juice fermented by strain DV10 with the addition of ammonium sulfate at 20 d, 25 d and 30 d decreased by 39.63%,24.02%and 20.16%respectively than the control group. Besides, wine samples with the addition of ammonium sulfate got higher sensory evaluation scores. The experiments also demonstrated that yeast strain R2 was more beneficial than yeast strain DV10 to litchi juice fermentation at low temperature and high sugar concentration, and the addition of ammonium sulfate was help-ful for high-sugar fermentation as well as wine quality improvement.%研究了荔枝汁接种R2酵母和DV10酵母后在低温(12℃)下的高糖(340 g/L)发酵能力.为了解决菌种在高渗透压下起酵迟缓的问题,通过添加硫酸铵补充发酵氮源强化菌种的发酵能力,考察了发酵过程中总糖、酒精度和高级醇等的含量变化规律.结果表明,添加硫酸铵可以明显促进发酵过程对糖的消耗,提升乙醇和酯类物质得率,降低高级醇和挥发酸生成量.添加硫酸铵的R2发酵果汁比空白样的高级醇含量在20 d、25 d及30 d时分别降低了37.52%、22.42%和22.40%;而添加硫酸铵的DV10发酵果汁高级醇含量比空白样分别降低39.63%、24.02%和20.16%,且添加硫酸铵的酒样均比其空白样的感官评价得分高.研究表明,荔枝汁接种R2酵母比DV10酵母更有利于低温高糖发酵,添加硫酸铵可以促进高糖发酵的进行,提升产品的品质.
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