Fish are highly perishable, and the methods by which anglers handle their catch from the time it is hooked until it is cooked can impact the quality of their meal.
Once a fish dies, irreversible spoilage begins. Enzymes and bacteria are responsible for this process. Enzymes that normally regulate a fish’s metabolism are left unchecked and start breaking down body cells. Fish caught while feeding may experience quicker rates of spoilage because digestive enzymes will already be active. A softening of flesh around the gut is often an indication of this process as enzymes quickly digest these tissues.
Bacterial growth in the body will accelerate as the fish decomposes. Fish may also become more susceptible to bacteria from the environment as the fish’s natural defenses are broken down. Exposure to the sun and
temperatures can quickly accelerate this process. One bacterium on a fish’s
body can multiply into millions of bacteria within hours if conditions are right.
This bacterial activity will contribute to the deterioration of the flesh. In
fact, fresh fish flesh is practically odorless, but fishy odors associated with
spoilage are the result of bacteria hard at work. Florida
While it is impossible to completely prevent spoilage, anglers can reduce this process by properly chilling their catch. This also reduces health risks associated with warmer temperatures.
One of the most recommended chilling methods for recreational anglers is the use of a brine slush-ice mixture. This is accomplished by combining at least two parts ice to one part clean seawater in an insulated cooler. Fish will chill four to five times quicker in slush ice because it will be surrounded by 32°F slush water.
To maximize the chilling process, seafood specialists recommend using at least one pound of ice per pound of fish. Cover the bottom of a cooler with several inches of ice and then surround the entire fish with another layer of ice. When deciding on how much ice to bring, anglers should also take into account the length of their trip, the surrounding air and water temperature, and if possible, the type and size of fish being targeted. Crushed or flaked ice is recommended because of the greater amount of surface area in contact with the fish, which will result in quicker chilling rates. Larger pieces can tear or bruise the skin more easily, but is better than no ice at all.
As the ice melts, water will help wash bacteria away from the surface of the fish. Water should be drained periodically to help remove accumulated bacteria. Continue to add ice as needed to maintain the appropriate slush mix.
Bleeding and gutting a fish will also enhance the quality of fish destined for your plate. Bleeding a fish will improve muscle appearance and flavor, and can reduce the cooling time once a fish is put on ice. Gutting a fish helps to remove sources of bacteria and enzymes that can increase spoilage rates. It will also reduce chilling time because a significant amount of body weight is removed. Keep the entrails intact to avoid contamination with other parts of the body. Knives and cutting surfaces should be clean to minimize further contamination. Once the fish is gutted, rinse the cavity with clean water to remove any excess blood, slime or viscera and pack it in the ice. Keep in mind that legally, fish must be landed whole with head and tail intact.