A new process for advanced utilisation of shrimp waste

A high quality chitosan for application in cosmetics can be produced from t he processing waste of Northern shrimp (Pandalus borealis). A major fractio n of the shrimp waste is protein tissues, which are normally wasted during conventional chitosan preparation. The present work shows that the shrimp w aste proteins can be hydrolysed by a commercially available protease (Alcal ase) and recovered as a protein hydrolysate with a high content of essentia l amino acids, before the scales are processed to chitosan. The Alcalase tr eatment had no adverse effect on either yield or quality of the chitosan. B y this new method the total recovery of Kjeldahl nitrogen was 68.5% as comp ared with only 12.8% by the conventional method. In addition, a concentrate of astaxanthin was recovered in the sediment after centrifugation of the c rude protein hydrolysate. This concentrate may be a valuable supplement in the feed to salmonid fishes. (C) 2001 Elsevier Science Ltd. All rights rese rved.