Abstract: Cow’s milk is rich in protein, fat, and other high-quality nutrients, which is an important nutritional source for infants. On the other hand, milk protein is the main factor inducing food allergy in infants and young children. In this study, five kinds of commercially available infant milk powder were selected for static digestion in vitro. The digestive stability of proteins in the five kinds of milk powder was analyzed by electrophoresis and degree of hydrolysis measurement. An enzyme-linked immunosorbent assay (ELISA) was used to evaluate the antigenicity of whey protein in milk powder. The results showed that α-lactalbumin and β-lactoglobulin showed good digestive stability in samples 1, 2, and 4. After gastrointestinal digestion, the antigenicity of α-lactalbumin and β-lactoglobulin decreased in sample 1 but increased in sample 2. The antigenicity of α-lactalbumin increased, while that of β-lactoglobulin decreased in sample 4. Both allergens had lower digestion stability in sample 3 and 5. The antigenicity of α-lactalbumin and β-lactoglobulin increased in sample 5. The antigenicity of α-lactalbumin increased while that of β-lactoglobulin decreased in sample 3.

Key words: infant allergy; milk powder; whey protein; in vitro digestion; digestive stability; antigenicity assessment

摘要： 牛乳含有丰富的蛋白质、脂肪等营养素，是婴幼儿重要的营养来源，牛乳蛋白也是诱发婴幼儿食物过敏的 主要因素之一。对5 种市售婴幼儿乳粉进行体外模拟静态消化，通过电泳、水解度测定分析蛋白消化稳定性，并利 用间接竞争酶联免疫吸附实验评价乳清蛋白的抗原性。结果表明：5 种配方乳粉中，α-乳白蛋白和β-乳球蛋白在样 品1、2、4中具有较好的消化稳定性，胃肠消化后，样品1中α-乳白蛋白和β-乳球蛋白的抗原性降低，样品2中2 种过 敏原蛋白的抗原性增加，样品4中α-乳白蛋白的抗原性增加，β-乳球蛋白的抗原性降低；α-乳白蛋白和β-乳球蛋白在 样品3和5中消化稳定性较低，经胃肠消化后，样品5中2 种过敏原蛋白的抗原性增加，样品3中α-乳白蛋白的抗原性 增加，β-乳球蛋白的抗原性降低。

关键词: 婴幼儿过敏；乳粉；乳清蛋白；体外静态消化；消化稳定性；抗原性评估