Li Baochang, Wang Yishu, Lin Wan, Ma Ruipeng, Xu Bin, Sun Jun
School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang, Jiangsu 212013, China.
School of Food Science and Engineering, Qingdao Agricultural University, 700 Changcheng Road, Qingdao, Shandong 266109, China.
Food Chem. 2025 Oct 30;490:145076. doi: 10.1016/j.foodchem.2025.145076. Epub 2025 Jun 7.
Black tea is vital for superior gel properties in preserved eggs, but the standardized usage guidelines are lacking due to limited understanding of its role in preserved egg white (PEW) formation. Thus, this study investigates the impact of black tea on gel properties of PEW and elucidates the underlying molecular mechanisms. Our findings reveal that black tea significantly improves PEW gel properties, with optimal effects at 1 % concentration. The reinforcement mechanism involves: (1) covalent interactions between black tea polyphenols (BTPs) and egg white proteins (EWPs) under alkaline conditions, promoting protein aggregation through increased β-sheet content and disulfide bonds; and (2) enhanced free metal ion concentration and uniform distribution in the curing solution, strengthening the "pore-blocking effect", thus further prevent the liquefaction of PEW gel. These findings provide a theoretical basis for optimizing preserved egg processing and highlight black tea's multifunctional role in improving gel properties.
红茶对皮蛋具有优异凝胶特性至关重要，但由于对其在皮蛋蛋清（PEW）形成中的作用了解有限，缺乏标准化的使用指南。因此，本研究调查了红茶对PEW凝胶特性的影响，并阐明了潜在的分子机制。我们的研究结果表明，红茶显著改善了PEW凝胶特性，在1%浓度时效果最佳。增强机制包括：（1）碱性条件下红茶多酚（BTPs）与蛋清蛋白（EWPs）之间的共价相互作用，通过增加β-折叠含量和二硫键促进蛋白质聚集；（2）固化溶液中游离金属离子浓度增加且分布均匀，增强了“孔隙阻塞效应”，从而进一步防止PEW凝胶液化。这些发现为优化皮蛋加工提供了理论依据，并突出了红茶在改善凝胶特性方面的多功能作用。
