摘要
按碱提酸沉法提取大米蛋白,用碱性蛋白酶将其水解,得到酶解产物及未消化蛋白.以大豆分离蛋白为阳性对照,对大米蛋白、大米蛋白酶解产物及未消化蛋白进行功能性质评价.结果表明:所得大米蛋白、酶解产物及未消化蛋白的纯度依次是77.25％,77.88％,72.53％;酶解产物的溶解度最大,大米蛋白的最小.大米蛋白及其酶解产物的功能性质对比评价结果:未完全消化的大米蛋白持水性优于酶解之前,达到324.93％,高于大米蛋白43.22％;大米蛋白的持油性最高,为463.2％,分别高于酶解产物及未消化蛋白10.42％,15.8％;在不同pH值条件下,酶解肽的乳化性均优于其他3种蛋白,在pH3.0时达到最大值48.80 mL/g;酶解肽的乳化稳定性也最强,在pH 5.0时乳化稳定性最强为43.01 min;各蛋白氨基酸组成较合理,种类齐全,富含谷氨酸和亮氨酸,赖氨酸含量缺乏.
Abstract
Rice protein was extracted by alkaline method and hydrolyzed by Alcalase.Peptides and undigested protein were obtained.The functional properties of rice protein and its hydrolysates were investigated using soy protein as a positive control.The results showed that the purity of rice protein,peptide,and undigested protein was 77.25％,77.88％ and 77.25％,respectively.The isoelectric point of rice protein and undigested protein was 6.0 and 5.0.The water-binding capacity of undigested protein was 324.93％,which was 43.22％ higher than that of rice protein while rice protein possessed the highest oil-binding capacity (463.2％),which increased 10.42％ and 15.8％ compared with peptides and undigested protein.Peptides had the maximum emulsibility (48.80 mL/g) and emulsion stability (43.01 min) at pH 3.0 and pH 5.0.Moreover,amino acid compositions of different samples were analyzed and the glu and leu contents were abundant and Lys had the lowest amino acid score (AAS).
基金项目
国家自然科学基金(31401522)
北京市教育委员会面上项目(KM201510011006)
北京市属高等学校高层人才引进与培训计划项目(CIT&TCD20130309)
北京市属高等学校高层人才引进与培训计划项目(IDHT20130506)
NETL
NSTL
维普
万方数据