Impact of elderly gastrointestinal alterations on in vitro digestion of salmon, sardine, sea bass and hake: Proteolysis, lipolysis and bioaccessibility of calcium and vitamins

This study aimed to analyze the effect of elderly gastrointestinal (GI) conditions on proteolysis, lipolysis and calcium and vitamins A and D3 bioaccessibility in salmon, sardine, sea bass and hake. For this purpose, cooked fishes were in vitro subjected to three elderly in vitro digestion models: E1 (oral elderly conditions), E2 (oral and gastric elderly conditions) and E3 (oral, gastric and intestinal elderly conditions)). In parallel, samples were digested under standardized GI conditions of a healthy adult as a control. Proteolysis was highly affected by elderly GI alterations (p < 0.05) (50% of reduction compared to control), being salmon and sea bass proteolysis extent (40 and 33%, respectively) the most affected with an important descend in leucine release. Calcium and vitamins bioaccessibility seemed to be also compromised for elders; however, the extent of the reduction highly depends on the fish type. Finally, these GI disorders did not negatively influence the bioabsorbable lipids of the fishes.