State Key Laboratory of Food Science and Resources, School of Food Science and Technology, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Advanced Food Manufacturing Equipment & Technology, Jiangnan University, Wuxi, Jiangsu, PR China.
Food Chem. 2025 Feb 1;464(Pt 3):141829. doi: 10.1016/j.foodchem.2024.141829. Epub 2024 Oct 29.
Polymerised whey is widely used in dairy products and can affect digestibility when its high-molecular-weight aggregates and gel structure are modified. This study investigated the digestibility, peptide profiles and satiety of modified whey protein isolate (MWPI) pre-heated with transglutaminase. Results showed that 43.06 % of MWPI was digested during the 4-h in vitro digestion, indicating a slow digestion rate. Compared with whey protein isolate (WPI), MWPI yielded 103 peptides with higher abundance following in vitro digestion, including 17 angiotensin-converting enzyme inhibitors and 1 dipeptidyl peptidase-4 inhibitor. Visual analytics indicated differential peptides located at distinct α-helix and β-sheet of β-lactoglobulin, α-lactalbumin and bovine serum albumin. MWPI gavage extended stomach retention time, decreased intestinal propulsion rate from 75.60 % (WPI group) to 33.72 % in 30 min and enhanced satiety within 120 min compared with WPI. Overall, whey polymerisation modulates protein-enzyme interactions, releasing different peptides and enhancing satiety.
聚乳清广泛应用于乳制品中，其高分子量聚集物和凝胶结构经修饰后会影响消化率。本研究探讨了经转谷氨酰胺酶预加热的改性乳清蛋白分离物（MWPI）的消化率、肽谱和饱腹感。结果表明，MWPI 在体外消化 4 小时内有 43.06%被消化，表明其消化速度较慢。与乳清蛋白分离物（WPI）相比，MWPI 在体外消化后产生了 103 种丰度更高的肽，包括 17 种血管紧张素转化酶抑制剂和 1 种二肽基肽酶-4 抑制剂。可视化分析表明，差异肽位于不同的β-乳球蛋白、α-乳白蛋白和牛血清白蛋白的α-螺旋和β-折叠区。MWPI 灌胃延长了胃潴留时间，使 30 分钟内的肠道推进率从 75.60%（WPI 组）降低至 33.72%，并在 120 分钟内增强了饱腹感。总之，乳清聚合调节了蛋白质-酶相互作用，释放出不同的肽并增强了饱腹感。
