热处理过程中牡蛎闭壳肌肌原纤维蛋白部分理化特性的变化

Physiochemical Changes of Myofibrillar Protein from Oyster Adductor Muscle During Heat Treatment

通过对牡蛎闭壳肌肌原纤维蛋白加热过程中浊度、溶解度、表面疏水性、α螺旋含量和总巯基含量的测定,研究了热处理过程中牡蛎闭壳肌肌原纤维蛋白理化特性的变化,结果表明,在20～40℃,牡蛎闭壳肌肌原纤维蛋白溶液的浊度、溶解度、表面疏水性、α螺旋含量和总巯基含量均无明显变化。在温度高于40℃时,随着温度的升高,牡蛎闭壳肌肌原纤维蛋白的浊度整体呈增大趋势,46℃下变化最为明显;溶解度在40～50℃变化最大,结合浊度的变化规律推测其变性温度为46℃;表面疏水性总体上逐渐增加,在40～50℃变化最大;α螺旋含量总体上逐渐降低,60℃变化最大,当温度达到70℃时约有80%的α螺旋结构被破坏;总巯基含量逐渐降低,50℃时下降最快。

The effects of heat treatment on the physiochemical properties changes of myofibrillar proteins from oyster adductor muscle including turbidity, solubility, surface hydrophobicity, α helix content and total sulphydryl content were investigated. The results showed that all the above indicators remained invariable when the heating tem- perature was 20 - 40 ℃. When the temperature was higher than 40 ℃ , obvious changes of the above indicators were obtained. As the temperature rised, the turbidity of the oyster myofibrillar proteins increased gradually and changed remarkably at 46℃. The solubility and surface hydrophobicity both changed obviously during 40 -50℃ and the dena- turation temperature was determined to be 46 ℃. The α helix content of myofibrillar protein decreased gradually and the most rapid changes occurred at 60 ℃. About 80% of the α helix was damaged when the temperature increased to 70℃. The total sulphydryl content decreased gradually when the temperature was higher than 40 ℃ , and the most ob vious changes were observed at 50 ℃.