It is estimated that 10-15 % of fish is spoiled during catch and further handling. Fish spoils quickly and should be used as soon as possible. It should be kept covered in the coldest part of the refrigerator for no longer than 2 days. Pre-packaged fish and shellfish can be refrigerated in the original package for a short time. Fish wrapped in butcher paper should be taken out and wrapped in aluminium foil or plastic wrap. Frozen fish maintains good quality when placed in the freezer immediately after purchase. Freezer temperatures of 0oF (-18oC) or lower are necessary to prevent loss of colour, texture, flavour and nutritive value. Cured fish is best kept covered in the refrigerators. Open canned fish should be used immediately or refrigerated.
Shrimp contains greater amount of free amino acids than fish and also highly active proteolytic enzymes, the cathepsins. They are therefore, highly perishable and require adequate refrigeration.
Cold storage: Fish are packed with crushed ice in suitable containers. This will prevent spoilage for 1-2 days. Fresh fish or dressed fresh fish in good condition will keep well for about a week, if they are packaged with crushed ice and stored at 0oC in a refrigerated room.
The dressed fish or fillets are preserved by coating with salt powder in the ratio of 1 part of salt to 3 parts of fish. The salt powder should contain sodium benzoate.
