Effects of tea polyphenols (TP) incorporation on physicochemical and antioxidative properties of whey protein isolate (WPI) coating were studied. Two WPI coating solutions were prepared by heating WPI solutions (pH 8, 90 °C) for 30 min and then TP was incorporated. TP addition could increase the negative zeta potential of 5% solution. The surface hydrophobicity index of both solutions was increased and intrinsic fluorescence intensity decreased greatly after addition of TP. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis (2 ethylbenzothiazoline-6-sulfonate) (ABTS) radical scavenging capacities of both solutions increased with increasing TP. Compared with apple pieces coated with whey protein only, those with TP containing whey protein coatings showed lower browning index and slight changes in weight loss during 24 h storage. Data indicated that TP could influence the physicochemical properties and improve the antioxidant activity of WPI coating solutions and can be used to retard the enzymatic browning of fruit during storage.

研究了茶多酚 (TP) 掺入对乳清分离蛋白 (WPI) 涂层理化和抗氧化性能的影响。通过将 WPI 溶液（pH 8，90°C）加热 30 分钟，然后加入 TP，制备了两种 WPI 涂层溶液。添加TP可以增加5%溶液的负zeta电位。添加TP后，两种溶液的表面疏水性指数均增加，固有荧光强度大大降低。两种溶液的 2,2-Diphenyl-1-picrylhydrazyl (DPPH) 和 2,2'-azinobis (2ethylbenzothiazoline-6-sulfonate) (ABTS) 自由基清除能力随着 TP 的增加而增加。与仅涂有乳清蛋白的苹果片相比，含有 TP 的乳清蛋白涂层的苹果片在 24 小时储存期间表现出较低的褐变指数和重量损失的轻微变化。