壳寡糖糖基化修饰对酪蛋白分子特性及流变性质的影响

摘要

研究利用转谷氨酰胺酶催化酪蛋白与壳寡糖发生糖基化交联反应,并控制反应时间(1、2h和4h)制备3种糖基化交联酪蛋白.经SDS-聚丙烯酰胺凝胶电泳、傅里叶红外光谱和游离氨基含量分析,表明酪蛋白同时发生了分子交联和糖基导入反应;经流变学分析,表明产物的表观黏度显著提高(剪切速率为1s-1时,反应4h的修饰产物的表观黏度增加了约10倍),且表现出剪切稀释特性;同时,频率扫描实验表明,产物分散液由类固体性质转变为类流体性质.%Transglutaminase was used to catalyze glycation cross-linking reaction of casein and oligochitosan.Three kinds of glycation cross-linked casein were prepared by controlling reaction time of 1,2,4 h.The results of SDS-polyacrylamide gel electrophoresis,Fourier infrared spectrum and analysis of free amino acid content indicated that the casein was crosslinked and glycosylated.The rheological analysis result indicated that the apparent viscosity of the product increased significantly and exhibited shear thinning behavior.The apparent viscosity of modified product obtained by reacting for 4 h increased by about ten times under the condition of shear rate 1 s-1.The frequency scan experiment showed that the product dispersion transformed from solid-like character into fluid-like character.