酶法制备木薯微孔淀粉的工艺优化

为了优化包埋粉末油脂的木薯微孔淀粉工艺、提高吸附性能，利用糖化酶和α- 淀粉酶对木薯淀粉进行处理，先通过六组单因素试验确定反应时间、反应温度、pH 值、底物浓度、酶浓度以及糖化酶和α- 淀粉酶配比最佳范围，再通过L18(37)正交试验，研究这些因素对木薯微孔淀粉吸附性能的影响。结果表明，当反应时间7h、温度60℃、pH6.0、底物浓度40%、酶浓度2.5%、糖化酶和α- 淀粉酶配比为1:4(m/m)时制备的木薯微孔淀粉的吸附性能最佳，木薯微孔淀粉对油脂的吸附性与原淀粉相比，从11.5% 提高到52%，提高了4.52 倍。

Optimization of Enzymatic Preparation of Microporous Cassava Starch

Microporous cassava starch was prepared by combined hydrolysis with glucoamylase andα-amylase. The effects of hydrolysis time and temperature, pH, substrate concentration, enzyme dosage and glucoamylase/α-amylase ratio on hydrolysis percentage and oil adsorption capacity of microporous cassava starch prepared were analyzed. On the basis of this, an orthogonal array design involving 18 tests was employed to optimize the six parameters for maximizing oil adsorption capacity. A maximum oil adsorption capacity was obtained by 7 h hydrolysis of native cassava starch at 60 ℃ and pH 6.0 using a mixture of glucoamylase and α-amylase (1:4, m/m) at the dosage of 2.5%. The oil adsorption capacity (52%) of microporous cassava starch was 4.52 times higher than that (11.5%) of native cassava starch.