摘要
该研究通过体外动态仿生胃消化模型,比较了巴氏杀菌和喷雾干燥处理对不同物种乳蛋白在胃消化过程中的凝块大小与微观结构、水解动力学和游离氨基酸释放的影响。微观结构显示,母乳和山羊乳中的蛋白质凝块聚集体比牛乳和绵羊乳的更小更松散,而热处理后的蛋白质凝块比原乳更细软松散。电泳结果显示,在胃消化120 min时,母乳和牛原乳中酪蛋白的消化速度快于山羊原乳和绵羊原乳。在不同热处理间,巴氏杀菌乳的消化率最高,其次是喷雾干燥乳和原乳。蛋白质水解度和肽分子质量分布一致表明,母乳在动态胃消化过程中的水解率显著低于动物乳且热处理加速了动物乳蛋白水解和小分子肽片段(<1 kDa)的生成,尤其是喷雾干燥处理。在游离氨基酸的释放量上,母乳显著高于动物乳(P<0.05),实验结果表明,热处理强度越高越有利于乳蛋白水解,但对游离氨基酸释放的抑制作用越强。综上所述,认为低热处理可以促进凝块消化,而高热处理会引起牛奶蛋白质的变性和聚集,提高凝块消化效率和水解成肽段的速度,但会减缓游离氨基酸的释放。该研究有助于更好地了解不同物种加工牛奶在胃消化率方面的差异。
The digestive behavior of proteins in milk is influenced by processing methods and species.This study compared the effects of pasteurization and spray-drying treatments on clot size and microstructure,hydrolysis kinetics,and free amino acid release of different species of milk proteins during gastric digestion by means of an in vitro dynamic bionic gastric digestion model.Microstructure showed that protein clot aggregates in human milk and caprine milk were smaller and looser than those in bovine milk and ovine milk,whereas heat-treated protein clots were finer and looser than those in raw milk.Electrophoresis results showed that casein digestion was faster in human milk and bovine raw milk than in caprine raw milk and ovine raw milk during gastric digestion for 120 min.Between heat treatments,the highest digestibility was observed in pasteurized milk,followed by spray-dried milk and raw milk.The degree of protein hydrolysis and peptide molecular weight distribution consistently showed that human milk(HM)had a significantly lower hydrolysis rate than animal milk during dynamic gastric digestion and that thermal treatments accelerated protein hydrolysis and generation of small molecule peptide fragments(<1 kDa)in animal milk,especially spray-dried treatments.The release of free amino acids was significantly higher in HM than in animal milk,and the experimental results indicated that the higher intensity of heat treatment was more favorable to milk protein hydrolysis,but the stronger the inhibition of free amino acids release.In summary,this study concluded that low heat treatment promoted clot digestion,whereas high heat treatment induced denaturation and aggregation of milk proteins,increased the efficiency of clot digestion and the rate of hydrolysis into peptides,but slowed the release of free amino acids.This study helps to better understand the differences in gastric digestibility of processed milk from different species.
作者
蒲志平
张丽娜
张凯
侯艳梅
赵怡晴
周鹏
PU Zhiping;ZHANG Lina;ZHANG Kai;HOU Yanmei;ZHAO Yiqing;ZHOU Peng(School of Food Science and Technology,Jiangnan University,Wuxi 214122,China;State Key Laboratory of Food Science and Resources,Jiangnan University,Wuxi 214122,China;Hyproca Nutrition,Co.Ltd.,Changsha 410011,China;Ausnutria Dairy(China)Co.Ltd.,Changsha 410011,China)
出处
《食品与发酵工业》
北大核心
2025年第6期33-41,I0001,I0002,共11页
Food and Fermentation Industries
基金
国家自然科学基金面上项目(32372246)。
关键词
乳蛋白
热处理
物种
婴幼儿
体外动态消化
milk protein
heat treatment
species
infant
in vitro dynamic digestion
