Enzymatic solubilization of an insoluble substrate, fish protein concentrate: Process and kinetic considerations

The solubilization of fish protein concentrate (FPC) by Bacillus subtilis protease (Monzyme) has been investigated. Conditions have been defined which eliminate the problems of microbial contamination and salt accumulation. A Kinetic treatment revealed that enzyme is adsorbed to the surface of the substrate, exposed to aqueous phase. The overall kinetics were described by a sequence of two first-order processes—an initial, fast reaction in which loosely bound polypeptide chains are cleaved from an insoluble protein particle, and a second, slower reaction in which more compacted core protein is digested.