Effect of Washing on Polyphenoloxidase Activity in Metapenaeus monoceros

Abstract

The enzyme, polyphenoloxidase, is responsible for the black spot formation in prawn. Sulphiting agents such as sodium metabisulphite and sodium bisulphite are widely used in prawn processing factories to control black spot, but sensitive persons are allergic to these chemicals. Repeated washing with optimum volume of potable water helped to leach out polyphenoloxidase from prawn considerably. 92% of the enzyme was leached out in the first two washing in the case of headless shell-on prawn and 53% was leached out in case of shell on whole prawn.