Abstract：
The instability and discoloration of (-)-epigallocatechin-3-gallate (EGCG) constrain its application in functional dairy products. Concurrently, challenges persist in the separation and utilization of whey in the dairy industry. By harnessing the interactions between polyphenols and whey proteins or their hydrolysates, this study proposed a method that involved limited enzymatic hydrolysis followed by the addition of EGCG and pH adjustment around the isoelectric point to obtain whey protein hydrolysates (WPH)-EGCG. Over 92 % of protein-EGCG complexes recovered from whey while ensuring the preservation of α-lactalbumin. The combination between EGCG and WPH depended on hydrogen bonding and hydrophobic interactions, significantly enhanced the thermal stability and storage stability of EGCG. Besides, the intestinal phase retention rate of EGCG in WPH-EGCG complex was significantly increased by 23.67 % compared to free EGCG. This work represents an exploratory endeavor in the improvement of EGCG stability and expanding the utilization approaches of whey.
摘要：
（-）-表没食子儿茶素-3-没食子酸酯（EGCG）的不稳定性和变色限制了其在功能性乳制品中的应用。同时,在乳品行业中，乳清的分离和利用仍然存在挑战。通过利用多酚和乳清蛋白或其水解产物之间的相互作用，这项研究提出了一种方法，该方法涉及有限的酶水解，然后添加EGCG并在等电点附近调节pH以获得乳清蛋白水解物（WPH）-EGCG。从乳清中回收了超过92％的蛋白质-EGCG复合物，同时确保了α-乳清蛋白的保存。EGCG和WPH之间的结合取决于氢键和疏水相互作用，显著增强了EGCG的热稳定性和储存稳定性。此外,与游离EGCG相比，WPH-EGCG复合物中EGCG的肠期保留率显着提高了23.67％。这项工作代表了在改善EGCG稳定性和扩大乳清利用方法方面的探索性努力。
