Hydrolysis behavior evaluation of sports protein supplements with different composition and dosage forms: In vitro dynamic gastric digestion

As a primary sources of sports nutrition, sports protein supplements can greatly compensate for post-exercise nutrient losses and minimize damage to health. The ingredients and dosage forms of protein supplements may affect their gastrointestinal digestion behavior, but there are few relevant studies. Herein, five protein supplements with different composition and dosage forms were selected to investigate the gastric digestion behavior and protein hydrolysis by in vitro dynamic digestion model. During gastric digestion, all samples tended to form aggregates as the pH decreased, thus affecting their rheological properties in the stomach. The results indicated that the protein powders were generally less hydrolyzed compared to liquid protein beverages, which was mainly related to their larger particle size distribution and microcapsule structure. One of the liquid supplements (M20) had the highest protein hydrolysis degree of around 35.74% and a half-empty time of 37.82 min. Moreover, casein-rich protein supplements were more hydrolyzed. These findings suggest that the composition and dosage forms of sports protein supplements will greatly affect their digestion behavior, resulting in varying degree of protein hydrolysis, ultimately affecting their digestion and absorption in the human body. Hence, sports supplements should be carefully designed to provide precise nutrition for the athletes and exercisers. • Evaluation of in vitro simulated gastric digestion behavior of sports protein supplements. • Liquid protein beverages showed higher protein hydrolysis than powder products. • CaseIn-rich sports protein supplements were more easily hydrolyzed.