Proteolysis of shrimp by-products (Peaneus monodon) from Madagascar

To generate and recover elements from shrimp heads, proteolysis was performed with commercial acidic or alkaline proteases for 22 h. The resulting phases were characterized for protein and lipid content and amino acid composition while the molecular profiles of soluble peptides were established. Whatever the protease used, more than the half of the initial dry matter was found into aqueous phase including most of the proteins while lipids were found to remain insoluble. Hydrolysates were mainly constituted by small peptides (> 80% below 1000 Da) with up to 14-15 amino acids identified. Moreover, all the hydrolyses have led to an increase of the amount of essential amino acids into the hydrolysates, including lysine. Thus, such proteolysis of shrimp heads can increase their potential nutritional value (small peptides with high content in essential amino acids) while allowing the concentration of lipids into insoluble phase and a partial demineralisation of the exoskeleton.