College of Light Industry and Food Engineering, Sichuan Univ., Chengdu, 610065, P. R. China.
J Food Sci. 2019 Aug;84(8):2086-2090. doi: 10.1111/1750-3841.14703. Epub 2019 Jul 11.
The oxidation and color stability of porcine hemoglobin (Hb) in the presence of tea polyphenols (TP), as well as the mechanism, were investigated using the methods of color and oxidation analyses, ultraviolet-visible and fluorescence spectroscopy. Results indicated that TP interacted with the tryptophan and tyrosine residues of Hb through inserting into its hydrophobic pocket. This interaction showed a concentration-dependent effect on Hb, which might lead to completely opposite results. The presence of TP (16 mg/L) disrupted Hb (16 mg/L) structure, and the exposure of heme iron facilitated the oxidation and discoloration of Hb. However, a lower level of TP should not break Hb structure but could work as an antioxidant and restrain the formation of methemoglobin. Consequently, TP (1.6 mg/L) considerably maintained the redness of Hb (16 mg/L, P < 0.05) when stored at pH 7.4 and 25 °C for 72 hr. Results may provide scientific information for the proper use of TP in blood and meat products. PRACTICAL APPLICATION: Proper utilization of tea polyphenols (TP) in food products is beneficial to improve antioxidant capacity and nutrition quality of food. We proved that it was potential to corporate TP into blood and meat products to prevent discoloration and oxidative deterioration.
研究了在茶多酚（TP）存在下猪血红蛋白（Hb）的氧化和颜色稳定性，以及其机制，方法是采用颜色和氧化分析、紫外-可见和荧光光谱法。结果表明，TP 通过插入其疏水口袋与 Hb 的色氨酸和酪氨酸残基相互作用。这种相互作用对 Hb 具有浓度依赖性效应，可能导致完全相反的结果。TP（16mg/L）的存在破坏了 Hb（16mg/L）的结构，暴露的血红素铁促进了 Hb 的氧化和变色。然而，较低水平的 TP 不应破坏 Hb 结构，但可以作为抗氧化剂并抑制高铁血红蛋白的形成。因此，当在 pH 7.4 和 25°C 下储存 72 小时时，TP（1.6mg/L）可显著保持 Hb（16mg/L，P<0.05）的红色。结果可为 TP 在血液和肉类产品中的合理使用提供科学信息。实际应用：在食品中合理利用茶多酚（TP）有利于提高食品的抗氧化能力和营养价值。我们证明，将 TP 掺入血液和肉类产品中以防止变色和氧化劣化是有潜力的。
