Entrapment of curcumin in hydrogels of whey peptides and its release during static in vitro gastrointestinal digestion

The suitability of a whey peptide hydrogel for entrapping curcumin compared with a whey protein isolate (WPI) gel was investigated. In addition, the release of curcumin entrapped in the peptide and protein gels was evaluated during static in vitro gastrointestinal digestion. The peptide hydrogel showed a 91% entrapment efficiency of curcumin compared with 99.9% for the WPI gel and at the end of intestinal digestion curcumin retention was close to 98% in the peptide hydrogel, whereas it was only 90% for the WPI gel. The preservation of the gel microstructure and, consequently, peptide-curcumin hydrophobic interactions during intestinal digestion could explain why curcumin release from the peptide hydrogel was lower than from the WPI gel. This work provides innovative results regarding the potential of using food-derived peptide hydrogels as an entrapment system for curcumin and its preservation during digestive conditions.(c) 2023 Elsevier Ltd. All rights reserved.