Extensive in vitro and, to a more limited extent, animal research have demonstrated the health potential of a wide set of egg protein hydrolysates; however, well-designed human intervention studies are scarce. Health claim assessment, however, sets high standards for characterisation of the bioactive peptides, investigation of the mode-of-action and convincing human intervention studies. In this review, we discuss the state-of-the-art and knowledge gaps related to egg-derived peptide bioavailability and bioactivity. In addition, we will formulate recommendations for appropriate design of future human intervention trials with egg-derived peptides.

Food-derived peptides can impact blood pressure through several mechanisms. However, their fate in the gastro-intestinal tract and bioavailability are difficult to assess because of their fast degradation and challenging analysis in physiologically relevant matrices. The aim of this study was to construct an in vitro bioavailability methodology in which luminal digestion is combined with Caco-2 cell transport. Egg ovalbumin hydrolysate, both in pure form and mixed with a food matrix, was used as a test case. Results indicate that a food matrix protected bioactive peptides from luminal digestion, especially in small intestine. Moreover, the Caco-2 absorption peak was extended over a longer time period (>60min) compared to the pure peptide solutions (~15min) which in total resulted in a 3–12 times higher absorption of the bioactive sequences after 60min compared to fasted conditions. These results suggest further investigation is warranted towards peptide-based functional foods with improved gastro-intestinal stability and longer-term release in the blood.