PRODUCTION OF CASEINOPHOSPHOPEPTIDES (CPPS) FROM SODIUM CASEINATE USING A RANGE OF COMMERCIAL PROTEASE PREPARATIONS

Sodium caseinate hydrolysates were generated at laboratory-scale using 28 commercial protease preparations of bacterial, fungal, plant and a nimal origin. Caseinophosphopeptides (CPPs) were enriched from these h ydrolysates by calcium chloride aggregation at pH 7.5 followed by etha nol precipitation of the aggregates. CPP yield ranged from 3.4 to 16.0 % (w/w) of the original protein. The calcium binding and solubilising abilities of the enriched CPPs ranged from 0.40 to 0.61 and 7.4 to 24. 0 mg Ca2+ mg(-1) CPP, respectively. Hydrolysis of sodium caseinate wit h Bioprotease N100L resulted in a 16.0% yield of CPPs which could solu bilise 19.1 mg Ca2+ mg(-1) CPP. Significant differences in the gel per meation and reversed-phase chromatography profiles for the various enr iched CPPs were evident. In general, no apparent relationship was obse rved between hydrolysate degree of hydrolysis (DH%), CPP yield, CPP ca lcium binding and solubilising abilities, and CPP apparent molecular m ass distribution and hydrophobic peptide profiles. (C) 1998 Elsevier S cience Ltd. All rights reserved.