不同盐对鲤鱼肌原纤维蛋白结构和凝胶特性的影响

The Influence of Salts on the Structural and Gel Properties of Common Carp(Cyprinus carpio) Myofibrillar Proteins

肌原纤维蛋白是鱼肉中的主要蛋白质,对鱼糜类制品的质量起到关键的作用。文中研究了NaCl、CaCl2和Na4P2O73种盐类及其浓度对鲤鱼肌原纤维蛋白结构特性(表面疏水性、蛋白聚合程度)和凝胶特性(质构、微观结构、蛋白浊度)的影响。结果表明:鲤鱼肌原纤维蛋白的等电点为5.5;3种盐加入肌原纤维蛋白后会引起肌原纤维蛋白发生一定程度的聚集,表面疏水性降低;随着盐浓度的增大,肌原纤维蛋白凝胶硬度、弹性、浊度降低;添加CaCl2比其它盐类更明显降低鱼糜的凝胶硬度、弹性和浊度,且差异性显著(P<0.05);NaCl和Na4P2O7使鱼糜凝胶微观结构更致密、CaCl2使鱼糜凝胶微观结构变得松散。因此,在鲤鱼肌原纤维蛋白中添加NaCl、CaCl和NaPO对鱼糜肌原纤维蛋白结构和凝胶特性均有不同程度的影响。

Common carp （ Cyprinus carpio） myofibrillar proteins are essential to the surimi products, and the influence of NaCl, CaCl2 and Na4P2O7 on myofibrillar proteins were examined. The isoelectric point carp myofibrillar proteins was 5.5. Salts effect on the carp myofibrillar proteins of molecular weight was not obvious in the SDS-PAGE, while with the increasing concentration of NaCl, CaCl2 and Na4P2O7, myofibrillar protein gel hardness, springiness, turbidity and surface hydrophobicity were all reduced. NaCl and Na4P2O7 modified the microstructure of myofibrillar gel, but CaCl2 caused gel microstructure to loose. Protein gel with CaCl2 salt solution had lower surimi gel hardness, flexibility and turbidity than others, and the difference was significant （P 〈 0.05）. The structure and gel properties of carp myofibrillar protein were changed when protein dissolved in salt （NaCl, CaCl2 and Na4P2O7） solutions.