木犀草素-乳清蛋白复合物对乳液物理稳定性和氧化稳定性的影响

以乳清蛋白为乳化剂，采用高压均质制备水包油乳液，分别在天然乳清蛋白组和热变性乳清蛋白组中添加 不同质量浓度（0.00、0.05、0.10、0.20、0.40 mg/mL）的木犀草素，探究天然和热变性乳清蛋白与木犀草素之间的 相互作用以及形成的乳清蛋白-木犀草素复合物与乳液稳定性的关系。通过测定荧光光谱、动态激光散射、界面物 质含量以及脂质氧化产物含量，研究热变性乳清蛋白与木犀草素复合物形成乳液的稳定性、界面吸附特性和抗氧化 性。结果表明：荧光光谱显示蛋白质和木犀草素相互作用发生荧光猝灭，二者之间形成了蛋白质-木犀草素基态复 合物；该复合物能显著抑制乳液脂质的氢过氧化物和丙二醛的形成（P＜0.05），可增强乳液的氧化稳定性，但是 对乳液的物理稳定性无显著影响（P＞0.05）。热处理不利于蛋白质在界面的吸附，但可以提高木犀草素在乳液界 面的吸附；而木犀草素的质量浓度对界面蛋白质的吸附没有显著影响（P＞0.05）。

Effect of Whey Protein-Luteolin Complexes on Physical and Oxidative Stability of Emulsions

In this study, heated and native whey protein were separately employed as emulsifiers to prepare oil-in-water (O/W) emulsions using a high-pressure homogenizer. Luteolin at different concentrations (0.00, 0.05, 0.10, 0.20 and 0.40 mg/mL) were added to the emulsions to form whey protein-luteolin complex. Fluorescence spectra, dynamic light scattering spectra, and the contents of protein and luteolin at the interface were determined in order to evaluate the potential influence of the complex as a natural antioxidant on the physical and chemical stability of emulsions. The formation of whey protein-luteolin complex was verified by analysis of fluorescence spectra and fluorescence quenching occurred. Based on the peroxide value (POV) and thiobarbituric acid reactive substance (TBARS) value, whey protein-luteolin complex significantly improved the oxidative stability (P < 0.05), but had no significant effect on the physical stability of emulsions (P > 0.05). The heating treatment could improve the adsorption of luteolin but blocked protein at the interface. However, luteolin content had no significant effect on the adsorption of protein (P > 0.05).