AbstractThe aim of the present study was to design methods for the digestion of fish proteins from processing wastes, leading to new possibilities for little‐used species or those generating a significant volume of residues. Residues of rayfish (Raja clavata) were used for the solubilisation of protein by hydrolysis treatment. The kinetics of hydrolysis was studied using rayfish enzymes, either by autolysis of the protein in a triturate of the raw material or by application of a multi‐enzyme preparation previously extracted from the viscera of the species. Their effectiveness was compared with that of two commercial enzymes, papain and pepsin. Optimum conditions of hydrolysis and enzymatic activity for digestion with rayfish enzymes were ascertained. The yield of material and the efficiency of digestion in each of the hydrolysis processes are reported. Copyright © 2003 Society of Chemical Industry