Quality of Fish Protein Hydrolysates from Herring ( <i>Clupea harengus</i> )

ABSTRACT Fish protein hydrolysates were prepared, using minced fillets and Al‐calase and papain, from raw herring and from herring defatted by ethanol extraction, cooking and pressing. Physicochemical, sensory and storage properties as well as the molecular weight sizes in spraydried hydrolysates were evaluated. Fat extraction before hydrolysis reduced degree of hydrolysis. Alcalase hydrolyzed samples to a higher degree than papain. Ethanol extraction reduced fishy odor to barely detectable levels. Papain hydrolysates were more bitter than those made with Alcalase. Color and nonenzymic browning measurements indicated darkening during 3 mo storage at room temperature (∼20°C).