糖基化对小米醇溶蛋白结构和消化性影响  

Effect of Glycosylation on the Structure and Digestibility of Millet Gliadin

作　　者：张玉静 黄凌立 郭峻[1] ZHANG Yu-jing;HUANG Ling-li;GUO Jun(State Key Laboratory of Food Nutrition and Safety,Key Laboratory of Food Quality and Health of Tianjin,College of Food Science and Engineering,Tianjin University of Science&Technology,Tianjin 300457,China)

机构地区：[1]省部共建食品营养与安全国家重点实验室,天津市食品质量与健康重点实验室,天津科技大学食品科学与工程学院,天津300457

出　　处：《食品研究与开发》2023年第2期13-20,共8页Food Research and Development

基　　金：天津市教委科研计划一般项目(2018KJ094)。

摘　　要：小米蛋白是优质蛋白重要来源,其中醇溶蛋白含量最高,加工方式对其结构和消化性的影响日益受到关注。以100、120、140、160、180℃加热处理25 min作为试验条件,研究热处理、D-木糖糖基化对小米醇溶蛋白结构和消化性的影响。结果表明:随着加热温度的升高,糖基化处理小米醇溶蛋白α-螺旋和无规则卷曲的含量下降而β-折叠的含量增加,表面疏水性、内源荧光强度降低,游离巯基含量减少,二硫键含量增加,消化率降低。除表面疏水性外,单独加热与糖基化处理,小米醇溶蛋白表现出相同规律,而糖基化的影响程度更显著。皮尔逊相关性分析显示,小米醇溶蛋白β-折叠含量及二硫键与蛋白消化率高度相关,因此,单独热处理及糖基化会引起小米醇溶蛋白的有序性结构比例增加,促使蛋白结构更加紧密而发生分子间聚集,从而造成小米醇溶蛋白的消化性降低。研究结果为进一步探索热处理对小米蛋白结构和营养消化特性的研究提供了理论基础。Millet is an important source of high-quality proteins and the content of gliadin is particularly high.The effect of processing method on the structure and digestibility of gliadin has increasingly come to our attention. This study aims to explore the influence of heating(100 ℃,120 ℃,140 ℃,160 ℃,and 180 ℃ for 25 min)and glycosylation with D-xylose on the structure and digestibility of millet gliadin. The results showed that the glycosylated gliadin showcased the decrease in content of α-helix and random coil,surface hydrophobicity,intrinsic fluorescence intensity,free sulfhydryl content,and digestibility,and increase in β-sheet content and disulfide bond content with the rise of heating temperature. The gliadin which was only heated demonstrated the same variation pattern of the above indexes with the glycosylated gliadin except the surface hydrophobicity,and glycosylation had more significant effect on the protein. Pearson’s correlation analysis suggested that β-sheet content and disulfide bond content of millet gliadin were highly correlated with protein digestibility. Therefore,heating and glycosylation can orderly increase structural elements of millet gliadin,make the protein structure more compact,and cause intermolecular aggregation,which will reduce the digestibility of the protein. The findings are expected to lay a theoretical basis for further exploring the influence of heating on the structure and nutrient digestion characteristics of millet protein.

关 键 词：小米醇溶蛋白 D-木糖 消化率 结构 糖基化 

分 类 号：TS201.21[轻工技术与工程—食品科学]