3种还原糖对芸豆清蛋白糖基化改性产物乳化性及结构的影响

Effect of three reducing sugars on emulsifying property and structure of maillard products of kidney bean protein

将葡萄糖、乳糖、果糖与紫花芸豆清蛋白(kidney bean protein,KPI)进行美拉德反应,并分析美拉德反应产物的乳化性及结构变化。结果表明,可通过与葡萄糖、果糖和乳糖发生美拉德反应来改善芸豆蛋白的乳化活性及乳化稳定性,其中果糖改善效果最好,芸豆蛋白的乳化性由原来的37.52 m ^2/g增加为98.69 m^2/g,乳化稳定性由16.88 min增加到28.68 min;芸豆蛋白与还原糖发生美拉德反应后,蛋白空间结构发生变化,表现为表面疏水性增强,表面巯基和总游离巯基含量降低,紫外吸收增加,内部荧光强度降低且发生红移,更利于蛋白吸附到油水界面,增强其乳化性。

The purpose of this study was to investigate the effect of sugars on the structural and emulsifying property of kidney bean protein modified by Maillard reaction.The results showed that the emulsifying activity and stability of kidney bean protein could be improved by Maillard reaction with glucose,fructose and lactose,and fructose was the best one.The emulsifying ability increased from 37.52 m^2/g to 98.69 m^2/g,and the emulsifying stability also increased from 16.88 min to 28.68 min;After Maillard reaction,the spatial structure of protein changed,which showed that the surface hydrophobicity increased,the content of surface sulfhydryl group and total free sulfhydryl group decreased.Moreove,the ultraviolet absorption increased,and the fluorescence intensity decreased with the red shift.These changes were more conducive to the protein adsorbing to the oil-water interface,thus enhanced the emulsification.