作　　者： ; ; ;

机构地区： 华南农业大学食品学院食品科学系

出　　处： 《华南农业大学学报》 2001年第4期84-87,共4页

摘　　要： 牛乳酪蛋白经胰蛋白酶水解 ,对水解物进行氨基氮含量、水解度 (DH)和游离氨基酸含量等测定 ,并通过SDS-PAGE电泳及Sephadex -G5 0凝胶层析 ,分析了相对分子质量的分布 结果表明 ,在水解条件为底物质量浓度 5 0g/mL、pH 7.4、温度 45℃、酶量 (m)∶底物量 (m) =1∶10 0 0时 ,DH随时间延长而增大 ,水解前期DH增长迅速 ,3h后增长缓慢 ,6 .0h的DH为 2 0 .48% 水解物中必需氨基酸含量约占游离氨基酸总量的 73 %～ 80 % ,此含量随水解时间的延长略有降低 ;水解物相对分子质量随DH的升高有所减小 ,经 2～ 3h水解的产物 ,相对分子质量分布主要集中于2 5 0 0～ 3 40 Bovine casein was hydrolyzed with trypsin, the amino nitrogen and free amino acid content, as well as the degree of hydrolysis ( DH ) of hydrolysates were determined. The distribution of relative molecular mass was analyzed by SDS-PAGE electrophoresis and Sephadex-G50 gel chromatography. The results indicated that, under the condition of 50 g/L substrate concentration, pH 4.5, amount of the enzyme ( m )∶amount of the substrate ( m ) = 1∶1 000, the DH increased with the increase of hydrolysis time. The increase of DH was fast at the beginning, but after 3 hours, it slowed down, and the DH was 20.48% after 6 hours of hydrolysis. The essential amino acid content in hydrolysates was 73%～80% of the total free amino acids, this percentage decreasing with hydrolysis time. The relative molecular mass of hydrolysates decreased with the increase of DH . The distribution of relative molecular mass ranged from 2 500 to 3 400 after 2 and 3 hours of hydrolyzation.

关 键 词： 牛乳酪蛋白 胰蛋白酶 水解物 特性分析 氨基氮 水解度 游离氨基酸

领　　域： [轻工技术与工程] [轻工技术与工程]