Solubilization of spray-dried lactalbumin by Alcalase

Abstract

SummaryEffects of the reaction variables pH, temperature, time, enzyme concentration and solids concentration on the hydrolysis and solubilization of lactalbumin slurries by Alcalase have been determined. Reaction progress curves, solubilization v. time, were very unusual with a maximum solubilization of 96% occurring at a short reaction time corresponding to a degree of hydrolysis of 11–12%. Further hydrolysis beyond this point produced a rapid decrease in solubilization to about 67%, followed by a further gradual increase in solubilization with prolonged hydrolysis. The unusual solubilization profile was also produced by increasing enzyme concentration at fixed reaction time. The effects of pH, temperature and solids concentration were similar to those found in the hydrolysis and solubilization of other insoluble proteins. The implications of the results for the design and operation of an enzymic hydrolysis process are discussed.