摘要
以乳清蛋白粉为原料通过酶解法制得乳清低聚肽,对其基础理化成分、氨基酸组成、血管紧张素转化酶(angiotensin converting enzyme,ACE)抑制活性和体外稳定性进行考察。结果表明,乳清低聚肽总蛋白质含量为(71.83±0.37)%,酸溶蛋白含量高达(61.71±2.42)%,水分含量为(4.86±0.23)%,灰分含量为(5.23±0.10)%,脂肪含量为(0.21±0.05)%(均为质量分数)。乳清低聚肽含有丰富的谷氨酸、亮氨酸、天冬氨酸等,并且必需氨基酸含量丰富。在pH 2-10,ACE抑制率在48.26%-50.91%波动,分子质量在1 000 u以下的总含量在93.57%-94.78%波动。在温度30-100℃时,ACE抑制率在48.67%-51.29%波动,分子质量在1 000u以下的总含量在93.75%-94.51%波动。分别经胃蛋白酶、胰蛋白酶、先胃蛋白酶后胰蛋白酶消化后,ACE抑制率在47.63%-50.93%波动,分子质量在150-1 000 u的组分所占比例略有降低,小于150 u的总含量略有升高,但升高不到2%,这说明乳清低聚肽具有一定的酸碱稳定性、热稳定性和消化稳定性。
Whey oligopeptides were prepared from whey protein powder by enzymolysis. The basic physical and chemical composition,amino acid composition,ACE inhibitory activity and in vitro stability were investigated. The results showed that the total protein content of whey oligopeptides,acid soluble protein,water,ash and fat content were (71. 83 ± 0. 37) %, (61. 71 ± 2. 42) %, (4. 86 ± 0. 23) %, (5. 23 ±0. 10) % and (0. 21 ± 0. 05) %,respectively. Whey oligopeptides were rich in glutamic acid,leucine,aspartic acid and essential amino acids. In the range of pH 2-10,the inhibition rate of ACE changed from 48. 26% to 50. 91%,and the total content of peptides with the molecular weight below1000 u fluctuated from 93. 57% to 94. 78%. Moreover,at 30-100 ℃,the inhibition rate of ACE fluctuated from 48. 67% to 51. 29%,and the total content of peptides with the molecular weight below 1 000 u fluctuated from 93. 75% to 94. 51%. After digestion with pepsin,trypsin,and pepsin digestion followed by trypsin digestion,respectively,the ACE inhibition rate changed from 47. 63% to 50. 93%,and the proportion of peptides with a molecular weight of 150-1 000 u decreased slightly. Meanwhile,the total content of peptides less than 150 u increased slightly. These results indicated that whey oligopeptides had acid-base stability,thermal stability and digestive stability under the above conditions.
作者
刘文颖
周明
冯晓文
凌空
谷瑞增
LIU Wenying;ZHOU Ming;FENG Xiaowen;LING Kong;GU Ruizeng(Beijing Engineering Research Center of Protein and Functional Peptides China National Research Institute of Food and Fermentation Industries Co.Ltd.,Beijing 100015,China)
出处
《食品与发酵工业》
CAS
CSCD
北大核心
2020年第16期24-29,36,共7页
Food and Fermentation Industries
基金
“十三五”国家重点研发计划(2016YFD0400604)
北京市科技创新基地培育与发展工程专项(Z191100002819001)
国家自然科学基金(31671963)。
关键词
乳清低聚肽
分子质量
ACE抑制作用
稳定性
whey oligopeptides
molecular weight
ACE inhibitory activity
stability
