双酶法水解米糠淀粉的工艺研究

摘要

为了提取米糠淀粉获得葡萄糖作为纳豆芽孢杆菌液态发酵的碳源,采用α-淀粉酶和糖化酶联合水解米糠中的淀粉,在单因素试验的基础上,运用正交试验设计方法对米糠中的淀粉水解工艺进行了研究和优化.结果表明,米糠中淀粉的最佳液化工艺条件为α-淀粉酶添加量16 u/g,温度60℃,CaCl2添加量0.2％,DE值为24.31％；最佳糖化工艺条件为糖化酶添加量200 u/g,温度60℃,pH 4.0,糖化时间6h,最大DE值为98.96％.该工艺使米糠中淀粉的提取率达到了89％,并基本都水解为了还原糖,可作为纳豆芽孢杆菌液态发酵的优质碳源.%In order to extract glucose from the rice-bran starch as the carbon source for the bacillus natto liquid state fermentation efficiently,α-amylase and glucoamylase was combined to hydrolyze starch in rice bran.Firstly we use the method of single-factor as basement to research,and then comprehensively use the orthogonal experimental to find the most optimal starch hydrolysis process.The result show that the most optimum liquefaction technique is as follows:the α-amylase's quantity is 16 u/g,temperature is at 60 ℃,the amount of CaCl2 is 0.2％,the value of DE is 24.31％.The most optimal saccharification technology is as follows:the amount of saccharifying enzyme is 200u/g,temperature is at 60 ℃,pH value is 4.0,the time of saccharification is for 6 h,and the biggest DE value is 98.96％.After improving the technological conditions,the extraction rate of starch in rice bran came up to 89％,almost hydrolyzed into reducing sugar,which could be the ideal carbon source for bacillus natto liquid state fermentation.