This study aimed to explore the mechanism influencing different addition amounts of capsaicin on the gel characteristics and microstructure of myofibrillar protein (MP) gels under conditions induced by hydroxyl free radicals (•OH). Results indicate that adding capsaicin can improve the gelling characteristics of the MPs. With an increased amount of capsaicin added, the oxidation of MPs by •OH decreased, and the number of oxidation sites decreased. Peptides located around residues 651–851 in the head domain SH1 and S2 subunits of the myosin heavy chain were susceptible to oxidation. Capsaicin primarily interacted with amino acids in SH1 (residues 1–151 and 601–651), reducing the effect of •OH on MPs and consequently decreasing the occurrence of MP aggregation. Capsaicin protected the structure and oxidation sites of MPs under oxidative conditions, ensuring the formation of an MP gel with uniformly dense pores during heating, thereby improving the texture characteristics and water-holding capacity of the gel.

中文翻译：

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不同辣椒素添加量对氧化条件下肌原纤维蛋白结构、氧化位点和凝胶性质的影响


本研究旨在探讨在羟基自由基 （•OH） 诱导条件下，不同辣椒素添加量对肌原纤维蛋白 （MP） 凝胶特性和微观结构的影响机制。结果表明，添加辣椒素可以改善 MPS 的胶凝特性。随着辣椒素添加量的增加，•OH 对 MPs 的氧化减少，氧化位点的数量减少。位于肌球蛋白重链的头部结构域 SH1 和 S2 亚基中残基 651-851 周围的肽易受氧化影响。辣椒素主要与 SH1 中的氨基酸（残基 1-151 和 601-651）相互作用，降低了 •OH 对 MP 的影响，从而减少了 MP 聚集的发生。辣椒素在氧化条件下保护 MPs 的结构和氧化位点，确保在加热过程中形成孔隙均匀致密的 MP 凝胶，从而改善凝胶的质地特性和持水能力。