汾酒酒醅有机酸的研究及酿造工艺的优化

采用高压液相色谱法分析了夏季汾酒酒醅中有机酸成分,以平板划线法分离得到夏季汾酒正常酒醅和酸度过高酒醅中的产酸细菌。研究了影响酒醅总酸度的因素进而对汾酒酿造工艺进行了优化。结果表明:酒醅中有机酸以乙酸和乳酸为主,从正常酒醅中分离到23株产乙酸细菌,5株产乳酸细菌,从酸度过高酒醅中分离到22株产乙酸细菌,29株产乳酸细菌。酒醅酿造的环境温度、入缸水分和装料量对酒醅总酸度影响较大。在此基础上,通过响应面试验,得到了适宜酸度的汾酒酿造条件,即环境温度20℃、入缸水分51%、装料量0.83 kg,出缸酒醅的总酸度为2.12(0.1 mol NaOH mL/g酒醅),与模型的预测值2.07基本相符。上述结果为解决汾酒夏季生产酒醅酸度过高问题提供了科学依据。

Study on Organic Acid of Fermented Grains and Optimization of the Brewing Process of Fen Liquor

The composition of organic acids in summer lees of fen liquor were analyzed via high performance liquid chromatography in this paper.Acidogenic bacteria were isolated from summer normal fermented grains and high acid fermented grains by flat crossed method.The influence factors of lees acidity were studied and fen liquor brewing process was optimized.Conclusion was: acetic acid and lactic acid were primarily organic acids in fermented grains;23 strains acetic acid bacteria and 5 strains lactic acid bacteria were isolated from normal fermented grains;23 strains acetic acid bacteria and 29 strains lactic acid bacteria were isolated from high acid fermented grains.Environmental temperature,moisture of fermented grains and amount of each urn packed greatly influenced the acidity of fermented grains.On this basis,suitable acid brewing conditions were obtained using the response surface method: with the environment temperature of 20 ℃,moisture of fermented grains of 51% and amount of each urn packed of 0.83 kg.The total acidity of fermented grains was 2.12(0.1 mol NaOH mL/g fermented grains),which was consistent with the model prediction of 2.07.The results provided scientific basis to solve the problem of high acid lees of fen liquor in summer.