不同酿造阶段添加富含谷胱甘肽酵母衍生物对梨酒品质的影响

为探究在不同酿造时间添加不同质量浓度富含谷胱甘肽酵母衍生物(glutathione-enriched inactive dry yeast,g-IDY)对梨酒品质的影响，以库尔勒香梨为原料，分别在乙醇发酵前、苹果酸-乳酸发酵前及陈酿前添加10、20、30 mg/L g-IDY进行梨酒酿造，待各组梨酒陈酿2个月后，对梨酒总酚及单体酚含量、抗氧化活性、有机酸含量、香气成分及感官评价进行分析。结果表明：在乙醇发酵前或陈酿前添加g-IDY能显著提高梨酒总酚含量、抗氧化能力及降低颜色指数(P<0.05)；添加g-IDY能提高梨酒中苹果酸、乳酸及柠檬酸等主要风味有机酸含量及提高梨酒总风味物质含量，在乙醇发酵前或陈酿前添加g-IDY有利于芳香族等香气化合物的形成并有助于减少部分不良气体的产生，但会导致更多H₂S生成。总体表明：在乙醇发酵前添加20 mg/L g-IDY所酿梨酒品质最好，总酚质量浓度为282 mg/L，总风味物质质量浓度为13 453.22 mg/L，感官评价达到88.7分。

Effect of Addition of Glutathione-Enriched Inactive Dry Yeast at Different Stages of Brewing on the Quality of Pear Wine

The present study was conducted in order to investigate the effects of adding different concentrations of glutathione-enriched inactive dry yeast (g-IDY) at different stages of brewing on the quality of pear wine. Wine was prepared from Korla fragrant pears. g-IDY was added at 10, 20 and 30 mg/L before alcoholic fermentation, malolactic fermentation or aging. After aging for two months, the contents of total and individual phenols, antioxidant activity, organic acid contents, aroma components and sensory evaluation of pear wine were analyzed. The results showed that adding g-IDY before alcoholic fermentation or aging significantly increased the content of total phenols and antioxidant capacity and decreased the color index of pear wine (P < 0.05). Besides, adding g-IDY increased the contents of malic acid, lactic acid and citric acid as well as total the content of flavor substances in pear wine. Adding g-IDY before alcohol fermentation or aging was beneficial to the formation of aromatic compounds and contributed to reducing the generation of some undesirable gas, but it led to the generation of more H2S. Together, these findings showed that pear wine prepared with the addition of 20 mg/L of g-IDY before alcoholic fermentation showed the best quality, with total phenol content of 282 mg/L, total flavor substance content of 13 453.22 mg/L and sensory evaluation score of 88.7 out of 100 points.