Water-holding capacity of enzymatic protein hydrolysates: A study on the synergistic effects of peptide fractions

The synergistic effects of peptides in bovine skin gelatin hydrolysate (BSGH) on the water-holding capacity (WHC), measured as cooking loss, were studied. These peptides were isolated from the hydrolysate in fractions with different hydrophobicities by reversed-phase chromatography on C18 separation columns. Each peptide fraction was included in the meat matrix at various concentrations for the study of water retention. The fraction with the highest WHC (F5) was obtained. The experimental design consisted of a central compound design with axial points; the independent variables were X1 (ingredient concentration in the meat sample) and X2 (concentration of fraction F5 in the ingredient). The dependent variable was cooking loss. The WHC studies showed substantial synergistic effects occurred between the fractions within the BSGH, and the peptide fractions reduced the cooking loss by 62.96% with respect to a sample without the ingredient. However, a decrease of 42.26% was observed for the F5 fraction. This fraction corresponds to the highest WHC applied for the concentration of 3 g/100 g. The results suggest a synergistic WHC effect of the peptides present in the BSGH since this effect was significantly reduced (p ≤ 0.05) when the peptide fractions were separated. •The synergistic effects of gelatin hydrolysate on WHC was studied.•The hydrolysate was separated into fractions with different hydrophilicities.•None of the fractions improved the WHC compared to the complete hydrolysate.•Synergistic effects between the peptides of the hydrolysate on WHC were found.