姜黄素共价修饰方法对面筋蛋白理化性质的影响及其在冷冻面团中的应用研究

Effects of Grafting Methods on the Physicochemical Properties of Gluten-Curcumin Conjugate and Its Application in Frozen Dough

本文分别采用碱法、超声波法和酶法来制备面筋蛋白-姜黄素共价复合物,同时探讨姜黄素共价修饰方法对面筋蛋白理化性质、冷冻面团流变学特性以及面包品质的影响。结果显示,三种方法诱导的共价交联使得面筋蛋白的游离氨基含量降低了26.98%~28.74%,游离巯基含量降低了10.80%~14.52%,并且共价交联破坏了分子内氢键,改变了蛋白质的二级、三级结构以及表面疏水性,增加了蛋白质的粒径和热稳定性。姜黄素共价修饰还可以改善冷冻面团的复合模量、蠕变恢复率以及硬度,并且同样可以改善冷冻面团面包的比容和硬度。这些结果说明,姜黄素共价修饰可以改善由面筋蛋白劣变所导致的冷冻面团品质下降。此外,与碱法和酶法制备的共价复合物相比较,超声波法制备的共价复合物在改善冷冻面团品质方面具有更好的效果。

In this study,the conjugate of curcumin and gluten were prepared through alkaline,ultrasonic,and enzymatic methods.The effects of grafting methods on physicochemical properties of gluten,rheology properties of frozen dough and the quality of resulted bread were evaluated.The results showed that the conjugation induced by alkaline,ultrasound,and enzyme led to the decreasing of free amino group content in the range of 26.98%~28.74%,and free sulfhydryl group content in the range of 10.80%~14.52%,respectively.The conjugation also resulted in the disrupture of intramolecular hydrogen bonding,changes of the secondary,tertiary structure and surface hydrophobicity,as well as increasing of particle size and thermal stability.The frozen dough with curcumin-gluten conjugate exhibited higher complex modulus,creep recovery and hardness than those without the conjugate.Furthermore,the incorporation of curcumin-gluten conjugate into frozen dough also helped to improve the loaf volume and the hardness of resulted bread.These results indicated that the conjugation between curcumin and gluten could prevent the deterioration of frozen dough.In addition,as compared with conjugate prepared from alkaline and enzymatic methods,the conjugate prepared from ultrasonic method showed the better ability in improving the quality of frozen dough.