复合酶法制备多孔淀粉条件的优化

采用α-淀粉酶和糖化酶复合水解法,以玉米淀粉为原料制备具有较高吸油率的多孔淀粉,研究了复合酶的作用条件对多孔淀粉吸油率和得率的影响,通过测定多孔淀粉的吸油率及扫描电镜分析,对多孔淀粉制备条件进行了优化.试验结果表明,α-淀粉酶在50℃、pH 6.0、水解14 h后,再在pH 4.0、50℃加入糖化酶水解14 h,α-淀粉酶和糖化酶配比为1:2,总酶量为2%时,制得多孔淀粉的吸油率56.62%、得率88.79%.扫描电镜结果显示淀粉颗粒表面小孔分布均匀,孔径适中,孔较深.

Optimized Preparation of Porous Starch by Compound Enzymes

Using compound enzymes of α-amylase and glucoamylase,a kind of porous starch with high rate of oil absorption was made from corn starch.The proper preparation conditions were obtained by determining oil absorp-tion rate and by scanning electron microscope(SEM).Results:The proper conditions for preparing porous starch by the compound enzymes are pH 6.0,α-amylase enzymolysis temperature 50 ℃,α-amylase enzymolysis time 14 h;then,pH 4.0,glucoamylase enzymolysis temperature 50℃,glucoamylase enzymolysis time 14 h;and total dose of compound enzymes 2%.ratio of α-amylase to glucoamylase 1:2.The oil absorption rate of the produced porous starch is 56.62%and yield is 88.79% under the conditions.SME shows that the apertures on the surface of starch granules distribute evenly and are deep and moderate size.