Peptide Profiling of Young Gouda Holland Cheese and Its Digests Obtained by In-Vitro-Simulated Gastrointestinal Digestion

Ripened cheeses contain bioactive peptides that are released from caseins by enzymatic hydrolysis during fermentation and ripening. However, the physiological relevance of these peptides depends on their stability during gastrointestinal digestion and their bioavailability. This study aimed to assess the impact of digestion on the peptide profile of the young Gouda Holland cheese. Using liquid chromatography coupled to electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS), we monitored the peptide profile changes during in vitro simulated gastrointestinal digestion. In total, 54 peptide sequences were identified in cheese (20), gastric (20), and intestinal digests (24). Ten peptides were derived from α_s1-casein, 43 from β-casein, and 1 from κ-casein. Most of the identified peptides were exclusive to one of the analyzed samples, revealing the alteration of the peptide profile during digestion. Two peptides were resistant to digestion, including β-CN(f193-209) with reported antithrombin, antimicrobial, and ACE-inhibitory effects. These results demonstrate the dual role of digestion in both degrading and releasing bioactive peptides and emphasize the importance of using digestion models to assess the bioactive potential of peptides in dairy products.