Emulsifying properties of a peptide from peptic hydrolysates of soy glycinin

Abstract

Soy glycinin was hydrolyzed by pepsin under controlled conditions. The emulsifying activity of the hydrolysates was found to be higher than that of glycinin. Fractionation of the peptides was performed in order to determine which peptides in the hydrolysates contributed to the enhanced emulsifying activity. A peptide fragment from an acidic subunit of glycinin A1a, corresponding to residues 209-275, was purified and was found to have a higher emulsifying activity at pH 4.0 than that of the original hydrolysate. Based on the hydropathic index, it is expected that the peptide possesses amphiphilic structure.