热处理及转谷氨酰胺酶对糖基化燕麦蛋白凝胶性质的影响

Effects of Heat Treatment and Transglutaminase on the Gelation Properties of Glycosylated Oat Protein

对燕麦蛋白及其乳糖糖基化燕麦蛋白进行热诱导和转谷氨酰胺酶诱导凝胶改性,探究2种不同诱导方式对燕麦蛋白及其糖基化产物凝胶性质及结构的影响。结果表明:与燕麦蛋白热诱导凝胶相比,其他3种燕麦蛋白凝胶的弹性、硬度和持水性均显著提高(P<0.05);酶诱导凝胶的质构性质(弹性、硬度、胶黏性)与持水性优于热诱导凝胶;糖基化改性蛋白凝胶的质构性质与持水性显著高于未糖基化改性蛋白凝胶(P<0.05)。酶诱导蛋白凝胶的表面疏水性分别高于两种热诱导蛋白凝胶;而糖基化改性蛋白凝胶的表面疏水性分别低于未糖基化改性蛋白凝胶。十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、傅里叶变换红外光谱、荧光光谱分析、微观结构分析进一步证明了转谷氨酰胺酶能引起燕麦蛋白发生分子间或分子内交联而形成大分子质量的交联产物,转谷氨酰胺酶诱导的燕麦蛋白凝胶具有更为致密的微观三维网络结构。研究表明,与热处理相比,转谷氨酰胺酶更能诱导燕麦蛋白及糖基化产物形成良好的凝胶,为燕麦粉的多元开发提供了一定理论基础。

Gelation of native oat protein and oat protein glycosylated with lactose was induced by heat or transglutaminase(TGase)treatment in order to investigate the effects of different induction methods on the gel properties and structure of oat protein.The results showed that compared with the heat-induced gel of oat protein,the elasticity,hardness,and waterholding capacity of three other oat protein gels were significantly improved(P<0.05).The texture properties(elasticity,hardness and viscosity)and water-holding capacity of the TGase-induced gels were better than those of the heat-induced gels,and the texture properties and water-holding capacity of the glycosylated protein gels were significantly higher than that of the non-glycosylated protein gels(P<0.05).The surface hydrophobicity of enzyme induced protein gel was higher than that of 2 kinds of heat-induced protein gel,respectively;the surface hydrophobicity of glycosylated modified protein gel was lower than that of non-glycosylated modified protein gel.Furthermore,sodium dodecyl sulfate-polyacrylamide gel electrophoresis(SDS-PAGE),Fourier transform infrared(FTIR)spectroscopy,fluorescence spectroscopy and microstructure analysis proved that TGase could cause intermolecular or intramolecular cross-linking of oat protein to form macromolecules,and the TGase-induced gel had a denser three-dimensional network microstructure.This study shows that TGase can induce native and glycosylated oat protein more effectively compared with heat treatment,which provides a theoretical basis for the diversified development of oat flour.