多酶复合水解法生产高水解度大豆寡肽的工艺优化

Optimization of the Production Conditions of Soybean Peptide with High Degree of Hydrolysis by Complex Enzymes

为提高大豆蛋白的水解度,生产低分子量大豆寡肽,采用碱性蛋白酶、风味蛋白酶和中性蛋白酶对大豆分离蛋白进行水解,并采用中心组合试验和Box-Behnken试验对复合酶的组成和酶解工艺进行了优化。研究结果表明:复合酶的最佳组成为碱性蛋白酶38.4%、风味蛋白酶27.2%、中性蛋白酶34.4%。最佳水解条件为pH 8.79、温度50.46℃、底物浓度10%g/ml,在此条件下酶解6 h,大豆分离蛋白的水解度可达28.7%,寡肽收率高达83.56%,所得大豆寡肽产品中肽含量高达81.3%,数均分子量低至850,各理化指标均符合国标GB/T22492-2008对一级大豆寡肽产品的质量要求。

The hydrolysis was carried out with alcalase, flavourzyme and neutral protease in order to improve the degree of hydrolysis （DH） of soy protein isolate （SPI） and produce soybean peptide with lower molecular weight. The composition of complex enzymes was studied by response surface methodlogy （RSM）, using a central-composite experimental design and the hydrolysis conditions were optimized by using a Box-Behnken design. The results showed that the best values in the complex enzymes for alcalase, flavourzyme and neutral protease were 39.6% （w/w）, 25.4% （ w/ w ） and 35% （w/w）, respectively. The optimal hydrolyzed conditions were found to be the pH of 8.79, the temperature of 50.46 ~C and the substrate concentration of 10% （w/w）. The DH of SPI was up to 28.7% and the yield of soybean peptide was 83.56% after hydrolyzing for 6 h in the optimized conditions above. The peptide content was up to 81.3%, the number average molecular weight was 850 in the product of soybean peptide, and all the physical and chemical indicators in the soybean peptide were in accordance with the requirements of GB/T 22492-2008.