采用激光共聚焦显微镜、SDS-PAGE、体积排阻色谱和ELISA等方法,比较1.4 μm孔径微滤和72 ℃下15 s巴氏杀菌处理对脱脂驼乳在体外模拟婴幼儿胃肠液中消化的影响。结果表明,微滤驼乳在模拟胃液中的絮凝物结构和持水量、酪蛋白残留率、游离氨基释放量、产生蛋白水解物的分子质量分布都与脱脂生驼乳更接近,而巴氏杀菌则降低了驼乳在模拟胃液中酪蛋白的降解速率,表明巴氏杀菌使酪蛋白对消化酶的抗性增加。此外,微滤更大程度地保留了脱脂驼乳中的免疫球蛋白G,且使免疫球蛋白G和胰岛素在消化过程中的保留更多。微滤驼乳具有与脱脂生驼乳相似的胃肠消化特性和活性成分保留。该研究可为高活性驼乳制品的生产提供理论依据。
Methods such as confocal laser scanning microscopy, SDS-PAGE, size exclusion chromatography and ELISA were employed to compare the effects of 1.4 μm pore size microfiltration and pasteurization at 72 ℃ for 15 s on the in vitro gastrointestinal digestion of camel skim milk under simulated infant conditions.The results showed that the structure and moisture content of gastric clots, percentages of remaining caseins, releasing amounts free amino groups, and molecular weight distribution of protein hydrolysate for microfiltered camel milk in simulated gastric fluids were closer to raw camel milk, while pasteurization reduced the degradation rate of casein of camel milk in simulated gastric fluids, suggesting that pasteurization increased the resistance of casein to digestive enzyme.Additionally, microfiltration retained immunoglobulin G in camel skim milk to a larger extent, and also retained more immunoglobulin G and insulin during digestion.Microfiltered camel milk has gastrointestinal digestion characteristics and bioactive component retention similar to raw camel skim milk.This study provides a theoretical basis for the production of camel milk products with high-bioactivity.
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