Peptidomic analysis of digested products of surimi gels with different degrees of cross-linking: In vitro gastrointestinal digestion and absorption

To investigate the cross-linking degree on the in vitro gastrointestinal digestion and absorption properties of surimi gel, three types of surimi gels with low, moderate, and high cross-linking degrees were prepared, and then in vitro digestion models (static and dynamic) and a Caco-2 cell monolayer model combined with LC-MS/MS were used to do peptidomic analysis of digestive and absorbed juices. The results showed that an increase in cross-linking degree promoted the release of peptides after gastrointestinal digestion. These peptides originated from the myosin head and rod, the rod was the main digestion region. More potential bioactive peptides from intestinal digestive juice could be transported through the intestinal epithelium. Compared with static digestion, dynamic digestion digested surimi gels more thoroughly, especially during gastric digestion. This study provides a theoretical basis and guidance for the production of surimi products with higher nutritional value and the in vitro digestion methods of gelatinous foods.