Enzymatic Conditions of an In Vitro Method to Study Protein Digestion

Abstract

ABSTRACT An in vitro digestion method was proposed for studying protein digestion. Protein (casein) was submitted to peptic proteolysis in a closed system followed by hydrolysis with pancreatic enzymes in a “digestion cell” with continuous elimination of digested products by dialysis. The peptic digestion was performed with a pepsin source of high specific activity (3152 units/mg protein) with an enzyme:substrate (E:S) ratio of 1: 250. The second‐step of proteolysis was carried out with pancreatin for 6 hr at an E:S ratio of 1:25. A 10 mM sodium phosphate buffer, pH 7.5, was used as the circulating dialysis buffer.