Effect of pasteurization and storage on the bioavailability of milk proteins during in vitro intestinal digestion and Caco-2 cell transport

This study fills a specific knowledge gap by comprehensively investigating the intestinal digestive dynamics and transport kinetics of pasteurized milk proteins during cold storage, utilizing dynamic in vitro digestion models, human colorectal adenocarcinoma cell line (Caco-2) transport simulations, peptideomics and amino acid analysis. The content of free amino acids during intestinal digestion and their transport capacity (excluding lysine) were highest in pasteurized milk stored for 7 days (PAST-D7), intermediate in pasteurized milk stored for 0 days (PAST-D0) and lowest in raw milk (RM). Conversely, the quantity and intensity of bioactive peptides during digestion decreased with pasteurization and storage. Additionally, pasteurization and storage reduced the intensity of bioactive peptides transported through Caco-2 cells and the types and intensity of potential allergenic peptides. These findings indicate that while pasteurization and storage may diminish some physiological benefits of milk, they may also enhance protein bioavailability and reduce allergenicity.