高压均质处理淀粉及大豆分离蛋白凝胶性质研究

Studies on Properties of Soybean Protein Isolate Mixed Gelation with Starches by High-pressure Homogenization

探讨不同添加量的不同变性淀粉对大豆分离蛋白凝胶性质的影响。将压热冷却高直链玉米淀粉、普通玉米淀粉制成糊化淀粉、老化淀粉、抗性淀粉,与大豆分离蛋白以质量比15∶85,20∶80,25∶75混合,在高压80 MPa均质两次,研究不同淀粉对大豆分离蛋白凝胶结构、质构及持水性的影响。研究结果表明,经高压80 MPa两次均质处理,大豆分离蛋白的凝胶硬度和持水性均增大;而不同添加量的不同淀粉对蛋白凝胶的硬度和持水性均显著增强(P<0.05)。在淀粉添加量为20%的条件下,蛋白凝胶硬度最大,而各样品间凝胶持水性差异不显著(P>0.05)。通过扫描电镜观察凝胶的微观结构,结果发现蛋白凝胶网状结构中产生孔洞,暴露出更多的蛋白结构表面活性基团,改善蛋白质功能特性,增大凝胶硬度并提高凝胶持水性。添加淀粉的大豆蛋白凝胶的亮度L*显著高于未添加淀粉的大豆分离蛋白(P<0.05)。

This study mainly investigated the properties of soybean protein isolate （SPI） mixed gelation with different starches by high-pressure homogenization. Gelatinized, retrograded, resistant starch prepared from maize, high-amylose maize starch through autoclaving-cooling treatment mixed with SPI at the ratio of 15：85, 20：80, 25：75, respectively, high-pressure homogenized at 80 Mpa two cycles. The properties of soybean protein isolate mixed gelation with different starches by high-pressure homogenization were investigated. The results showed that after two cycles of 80Mpa high-pres- sure homogenization, gel hardness and water holding capacity （WHC） of SPI was increased, while different amounts of different starches significantly enhance the gel hardness and increased WHC of SPI （P〈0.05）. When the content of starch is 20%, gel hardness to be the maximum, whereas the WHC of each samples were not changed significant （P〉0.05）. Microstructure of the gel observed by scanning electron microscopy found to expose more surface active groups of protein structure and improve the functional properties of proteins, increasing the gel hardness and improved WHC. The addition of starch significantly increased the lightness （L＊） of gel （P〈0.05）.