Ex vivo digestion of omega-3 enriched buffalo skimmed milk

Abstract

The aim of this study was to investigate whether the protein digestion in skimmed buffalo milk was affected by adding cod liver oil as a source of omega-3 fatty acid to the milk. Human gastrointestinal enzymes were used in ex vivo digestion. After gastric and duodenal digestion, 32% of the neutral lipid underwent lipolysis. Both the omega-3 fatty acids, eicosapentaenoic (C20:5 n-3) and docosahexaenoic (C22:6 n-3) acid showed 23% lipolysis. Most of the caseins were degraded after 20 min gastric digestion; the tiny traces found after 40 min gastric digestion were digested completely after 5 min duodenal digestion. The α-lactalbumin and β-lactoglobulin were resistant to gastric digestion, however, readily digested after 5 min duodenal digestion. Addition of cod liver oil did not affect the milk protein digestion and subsequent peptide generation. Thereby, enrichment of skimmed milk by cod liver oil could be a good nutritional source of omega-3 fatty acids.

Keywords

• Omega-3 fatty acids
• Fortification
• Ex vivo digestion
• Casein
• β-Lactoglobulin
• Peptides