复合酶-间歇超声法制备玉米多孔淀粉工艺

Preparation Technology of Corn Porous Starch by Complex Enzyme-Intermittent Ultrasonic

以玉米淀粉为实验原料,以甲基紫吸附率为响应值,采用Plackett-Burman (PB)和Box-Behnken Design (BBD)法优化复合酶-间歇超声法制备多孔淀粉工艺。同时,用扫描电镜(SEM)对多孔淀粉颗粒的微观形态进行了分析。Box-Behnken响应面法优化结果表明,制备玉米多孔淀粉最佳条件为:水浴加热预处理15 min,底物淀粉浓度33. 33%、酶用量0. 4%(相当于10. 87 IU/g)、酶配比(糖化酶:α-淀粉酶)9:1、pH 5. 0,反应温度50℃、反应时间10 h,超声功率250 W,超声时间29. 83 min,吸附率为62. 42%,是原淀粉对甲基紫吸附率的2. 8倍。电镜微观形态分析显示,多孔淀粉微孔的吸附率变化与其微观结构变化相吻合。

In this study, native corn starch was selected as the experimental material, the adsorption rate of methyl violet was chosen as the response value, Plackett-Burman(PB) and Design Box-Behnken(BBD) method were used to optimize the porous starch preparation of complex intermittent enzyme-ultrasonic. Moreover,the microstructures of porous starch granules were compared by SEM. The best preparation conditions of porous corn starch obtained by Box-Behnken response surface optimized result was shown as follows: heating in a water bath for 15 min for pretreatment, substrate concentration of starch 33. 33%,amount of enzymes 0. 4%(10. 87 IU/g), ratio of enzyme(diastatic enzyme: α-amylase) 9:1, pH 5.0, reaction temperature 50 ℃, reaction time 10 h, ultrasound sonication power 250 W and ultrasonic time 29. 83 min, and the methyl violet adsorption rate of porous starch was62. 42%, which was 2. 8 times as much as that of native starch. Plus, the SEM images showed that the change of absorption ratio of porous starch was identical to the changed microstructure of porous starch granules.