磷酸盐-大豆分离蛋白联合处理对草鱼肌原纤维蛋白凝胶化的影响

Effects of Combined Treatment of Phosphates and Soybean Protein Isolate on the Gelation Properties of Myofibrillar Proteins from Grass Carp

为探讨磷酸盐(三聚磷酸钠、六偏磷酸钠、焦磷酸钠(tetrasodium pyrophosphate,TSPP))和大豆分离蛋白(soy protein isolate,SPI)对草鱼肌原纤维蛋白凝胶化的影响,采用热处理方法,将不同质量浓度的磷酸盐、SPI与草鱼肌原纤维蛋白混合制成凝胶。用黏度、嫩度、持水性、显微结构和粗糙度表征凝胶特性。结果表明:磷酸盐可促进蛋白与水的相互作用,有利于蛋白形成稳定、有序的交联网络并保存水分;SPI增大了蛋白间的交联程度,促进凝胶保水能力,提高蛋白凝胶体系的稳定性;磷酸盐、SPI的加入显著提高了凝胶品质,TSPP-SPI联合处理组较其他处理组具有更好的持水性(P<0.05)、嫩度(P<0.05)及适中的黏度(P<0.05),其中,当采用1.2 g/100 mL TSPP、5 g/100 mL SPI体积比1∶3处理时,凝胶具有嫩度大(P<0.05)、持水性好(P<0.05)、黏性适中(P<0.05)、粗糙度小(P<0.05)等特点,该处理方式能够显著提高草鱼肌原纤维蛋白凝胶特性。

In order to explore the effects of phosphate(sodium tripolyphosphate,sodium hexametaphosphate,tetrasodium pyrophosphate)and soy protein isolate(SPI)on the gelation properties of grass carp myofibrillar protein(MP),heat-induced gels were prepared from MP with different concentrations of phosphate and 5 g/100 mL soy protein isolate(SPI)added,and their viscosity,tenderness,water-holding capacity(WHC),microstructure and roughness were evaluated.The results showed that phosphate promoted the interaction between protein and water,thus facilitated the formation of stable and ordered cross-linked network and preserved moisture.SPI increased the degree of crosslinking between proteins,promoted gel WHC,and improved the stability of the gel system.The addition of phosphates and SPI significantly improved gel quality.Compared to the other treatments,sodium pyrophosphate-SPI treatment showed better gel WHC(P<0.05)and tenderness(P<0.05)as well as medium viscosity(P<0.05).The gel added with a mixture of 1.2 g/100 mL sodium hypophosphate and 5 g/100 mL SPI at a volume ratio of 1:3 was characterized by high tenderness(P<0.05),good WHC(P<0.05),medium viscosity(P<0.05),and small roughness(P<0.05)indicating that this treatment could significantly improve the gel properties of MP from grass carp.