碱性蛋白酶水解豆粕制备大豆多肽

Production of Soybean Peptide by Alkaline Protease Hydrolysis of Soybean Meal

采用碱性蛋白酶水解豆粕制备大豆多肽,以蛋白质的转化率和水解度为指标,通过单因素试验,考察影响酶解工艺的主要因素,并利用正交试验确定最佳酶解条件.结果表明:在温度为55℃,pH值为9.5,加酶量为0.15%,底物质量分数为7%的最佳条件下,水解豆粕3h,其转化率可达75.73%,水解度为49.30%.液相色谱分析表明:酶解液的大豆多肽相对分子质量分布主要集中在5 000以下,占比达80.21%.

The soybean meal was hydrolyzed to prepare soy peptide with alkaline protease. During the experiment, the conversion rate and degree of hydrolysis were selected as the main indexes to investigate the chief factors influencing enzy- molysis technology with single-factor experiment, then the optimum conditions were studied using orthogonal test. It was shown that the optimum conditions of enzymatic hydrolysis were temperature 55 ℃, pH 9.5, protease concentration 0. 15%, substrate concentration 7%. Under the optimum conditions, the conversion rate and degree of hydrolysis were 75.73% and 59. 30% respectively when hydrolysis for 3 h. The relative molecular weight distribution of soybean peptides was determined by size exclusion chromatography. Result showed that there was 80. 21% of soybean peptide with molec- ular weight less than 5 000.