Spatial-temporal mapping of the intra-gastric pepsin concentration and proteolysis in pigs fed egg white gels

• Published in: Food chemistry Vol. 389; p. 133132
• Main Authors: Nau, Françoise, Le Feunteun, Steven, Le Gouar, Yann, Henry, Gwénaële, Pasco, Maryvonne, Guérin-Dubiard, Catherine, Nyemb-Diop, Kéra, Dupont, Didier
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 30.09.2022; Elsevier
• Subjects: Amino acid absorption; Food and Nutrition; Food structure; In vivo digestion; Life Sciences; Protein gel; Protein gel; AA; In vivo digestion; OPA; EW; DH; EWG; EAA; DTT; IS; Food structure; Amino acid absorption; amino acid; egg white; Amino acid absorpt; degree of hydrolysis
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2022.133132

•Gastric fluids distribute differently over the stomach depending on egg white gel.•Pepsin accumulation started at the pylorus/antrum region in pigs fed egg white gels.•Intra-gastric pepsin distribution never became uniform even after 6 h digestion.•The more acidic and soft egg white gel resulted in an earlier gastric proteolysis.•The softest egg white gel sped up and increased the amino acid transfer in blood. While there is a consensus that food structure affects food digestion, the underlying mechanisms remain poorly understood. A previous experiment in pigs fed egg white gels of same composition but different structures evidenced such effect on food gastric disintegration. In this study, we detailed the consequences on intra-gastric pH, pepsin concentration and proteolysis by sampling throughout the stomach over 6 h digestion. Subsequent amino acid absorption was investigated as well by blood sampling. While acidification was almost homogeneous after 6 h digestion regardless of the gel, pepsin distribution never became uniform. Pepsin started to accumulate in the pylorus/antrum region before concentrating in the body stomach beyond 4 h, time from which proteolysis really started. Interestingly, the more acidic and soft gel resulted in a soon (60 min) increase in proteolysis, an earlier and more intense peak of plasmatic amino acids, and a final pepsin concentration three times higher than with the other gels.