高酰基结冷胶对乳清分离蛋白热诱导凝胶特性的影响

蛋白质-多糖凝胶具有良好的稳定性和机械强度,在稳定和传递生物活性物质、营养强化剂方面的应用前景广阔。该研究以乳清分离蛋白、高酰基结冷胶为原料制备热诱导混合凝胶,分析高酰基结冷胶对乳清分离蛋白-高酰基结冷胶混合凝胶的凝胶强度、保水性及显微结构等,揭示乳清蛋白-高酰基结冷胶凝胶形成机理。结果表明,高酰基结冷胶促使蛋白质巯基暴露从而使凝胶形成稳定结构,提高混合凝胶的凝胶强度和保水性,且随着高酰基结冷胶含量增加而显著增大,其质量浓度为4 g/L时,复合凝胶的凝胶强度最大,为26.97 g;保水性最好,为97.41%;透光率最低,为1.87%。温度扫描结果表明,增加高酰基结冷胶可以提高乳清分离蛋白的相转变温度,傅里叶红外光谱显示,乳清分离蛋白与高酰基结冷胶存在分子间作用力,扫描电子显微镜表明高酰基结冷胶诱导混合凝胶形成结构紧密的三维网络结构。该研究为拓展乳清分离蛋白和结冷胶的新型凝胶食品,提高传统食品的质量,改善食品的加工工艺提供基础理论数据。

Effect of high acyl gellan gum on the characterization of heat-induced gelation of whey protein isolate

There are great applications of protein-polysaccharide gel for prospects stability and mechanical strength in stabilizing,transferring bioactive substances and nutritional enhancers.A heat-induced gelation was prepared with whey protein isolate(WPI)and high acyl gellan gum(HG).The gel strength,water holding capacity and microstructure of whey protein isolate-high acyl gellan gum gelation(WPI-HG)were analyzed,the formation mechanism of whey protein-high acyl gellan gum was revealed.The results showed that HG could enhance the gel strength and water holding capacity of the gelation,the gel strength reached 26.97 g,water holding capacity was 97.41%,and the light transmittance was 1.87%with HG concentration of 4 g/L.Sulfhydryl group which could form S-S stable structure in the composite solution increased significantly with addition of HG.Rheological properties results revealed that the phase transition temperature of composite gel could be increased with HG.Fourier transform infrared spectroscopy(FTIR)showed that there was an intermolecular force that occurred between WPI and HG.Scanning electron microscopy(SEM)showed that there was a tightly three-dimensional network structure formed in WPI-HG.This study could provide a basic theoretical data for the development of new gelation foods for WPI and HG and food processing.