The major cause of spoilage in fresh fish is bacterial attack. When fresh fish is harvested, it starts to spoil immediately due to the growth of bacteria on the surface and inside the fish. Bacteria present in the environment or on the equipment used during processing can also contaminate the fish. The bacteria breaks down the proteins and lipids in the fish, leading to the production of unpleasant odors and flavors, sliminess, discoloration, and other signs of spoilage. To prevent bacterial growth, fresh fish should be stored at low temperatures, preferably below 4°C, and for a short period of time.