双酶法水解玉米淀粉的工艺研究

Research on the Degradation of Maize Starch by Double-enzyme Method

模拟水解玉米淀粉的生产工艺,初步探讨液化时间、液化过程引入Ca2+对糖化质量的影响。研究表明,α-淀粉酶和糖化酶的最适pH分别为5.0和4.2;在淀粉水解过程中,一定量的Ca2+能促进α-淀粉酶的活性并能增强其热稳定性,但对糖化酶的活性却表现为抑制作用。在保证正常液化的前提下,应尽可能减少Ca2+用量。液化时间选定90～130min为宜。糖化时间并不是愈长愈好,只有定期对产品实施监控,才能获得高DE值的葡萄糖浆。

The hydrolysis of maize starch was simulated. The effects of liquefaction time and the addition of Ca^2＋ in liquefaction process on the saccharification quality were investigated. The results indicated that the optimum pH values of α-amylase and glucoamylase were 5.0 and 4.2 respectively, the addition of Ca^2＋ during starch hydrolysis could improve the activity and the thermal stability of α-amylase, however, it behaved as an inhibitor to glucoamylase activity. Therefore, the addition of Ca^2＋ should be reduced as possible to ensure normal liquefaction. The proper liquefaction time should be between 90 and 130 min. Longer saccharification process did not stand for better production quality, only the monitoring of the products periodically could ensure glucose syrup with a higher dextrose equivalence （DE）.