茶多酚对羊肉肌原纤维蛋白凝胶特性的影响

研究茶多酚对羊肉肌原纤维蛋白凝胶特性的影响，将不同添加量（0.00%、0.01%、0.05%、0.10%、0.50%、1.00%）的茶多酚加入到羊肉肌原纤维蛋白中，测定肌原纤维蛋白表面疏水性、乳化性能、保水性、质构特性，观察羊肉肌原纤维蛋白凝胶微观结构。结果表明，与对照组相比，茶多酚添加量为0.10%时，羊肉肌原纤维蛋白的表面疏水性最小，疏水基团暴露程度最轻，乳化活性指数达到最大（4.88 m2/g），乳化稳定性指数（86.54%）和保水性（95.22%）均达到最佳；随着茶多酚添加量的增加，羊肉肌原纤维蛋白凝胶的硬度、咀嚼度、胶着度均显著上升（P＜0.05），弹性、内聚性、回复性整体呈下降趋势（P＜0.05）。结论：添加适量茶多酚可以显著改善羊肉肌原纤维蛋白的凝胶特性，并且凝胶的微观结构更加致密、空隙更小、形状规则且分布均匀；茶多酚与肌原纤维蛋白的非共价结合和共价结合可能会影响蛋白质的功能特性，并且这种作用强度随着茶多酚添加量的变化而变化。

Effect of Tea Polyphenols on Gelation Properties of Mutton Myofibrillar Protein

In this paper, the effects of tea polyphenols on the gelation properties of mutton myofibrillar protein (MMP) were investigated. MMP added with different levels of tea polyphenols (0.00%, 0.01%, 0.05%, 0.10%, 0.50% and 1.00%) (m/m) were determined for surface hydrophobicity, emulsifying properties, water holding capacity and texture characteristics. Besides, the microstructure was observed. The results showed that compared with the control group (without adding tea polyphenols), addition of 0.10% tea polyphenols decreased the surface hydrophobicity and the exposure of hydrophobic groups to the lowest level, but increased emulsifying activity index (EAI) to the maximum (4.88 m2/g). MMP added with 0.10% tea polyphenols showed the best emusifying stability (86.54%) and water holding capacity (95.22%). With increasing concentration of tea polyphenols, the hardness, chewiness and gumminess of myofibrillar protein gels significantly increased (P < 0.05), while the springiness, cohesiveness and resilience decreased (P < 0.05). In conclusion, addition of an appropriate amount of tea polyphenols significantly improved the gelation properties of MMP, making the microstructure denser with smaller voids, and more regular in shape with a uniform distribution. Tea polyphenols and MMP can bind both non-covalently and covalently, affecting the functional properties of myofibrillar protein, and this effect varies with the concentration of tea polyphenols.