Fish wastes have also been utilised for the production of fish
powders or fish protein hydrolysates, used as nitrogen source for
microbial growth and enzyme production. Autolytic process, which
depends only on endogenous enzymes, is considered to be
economically advantageous; however, exogenous commercial enzymes
are sometimes preferred since they allow controlled hydrolysis,
hence control over the properties of the resulting
products. Many enzymes have attracted interest for the hydrolysis
of fish proteins