基于复合酶制剂抑菌的糖蜜无酸发酵酒精技术的研究

Study on the Technology of Alcohol Fermentation from Molasses Without Acid Based on Compound Enzyme

糖蜜原料中由于含有灰分、胶体和杂菌等,发酵容易感染杂菌。传统糖蜜发酵酒精通过添加浓硫酸调节pH值来抑制杂菌,硫酸容易造成设备腐蚀、结垢和环境污染等问题。为避免有酸发酵的不利影响,并提高发酵酒精浓度,该研究以糖蜜为原料,添加复合酶制剂代替硫酸抑菌,在糖蜜酒精发酵中分别添加3种酶制剂进行单因素试验,结果表明,果胶酶最适浓度为15 U/g,木瓜蛋白酶最适浓度为16 U/g,溶菌酶最适浓度为20 U/g。通过正交实验优化复合酶制剂添加量,最佳组合为:果胶酶20 U/g,木瓜蛋白酶16 U/g,溶菌酶24 U/g,对应的发酵酒精浓度为9.96%(体积分数)最高,比添加上述单种酶发酵最高酒度分别提高了3.75%、11.91%、2.68%。

The raw materials of molasses contain ash,colloid and miscellaneous bacteria,which are easy to be infected by fermentation.Traditional molasses fermentation alcohol suppresses miscellaneous bacteria by adding concentrated sulfuric acid to adjust the pH value.Sulfuric acid is easy to cause equipment corrosion,scaling and environmental pollution.In order to avoid the adverse effects of acid fermentation and improve the alcohol concentration of fermentation,molasses was used as raw material in this study,and compound enzyme preparations were added instead of sulfuric acid to inhibit bacteria.First,three kinds of enzyme preparations were added to molasses alcohol fermentation for single factor experiments.The results showed that the optimal concentration of pectinase was 15 U/g,the optimal concentration of papain was 16 U/g,and the optimal concentration of lysozyme was 20 U/g.Then,the amount of complex enzyme was optimized through orthogonal experiments.The best combination was:pectinase 20 U/g,papain 16 U/g,lysozyme 24 U/g,and the corresponding fermentation alcohol concentration was 9.96%(volume fraction),which was relatively the highest,the highest alcohol content increased by 3.75%,11.91%and 2.68%respectively compared with the addition of the above-mentioned single enzyme preparation.