Tips for preserving fresh fish
Freezing fresh caught fish is the easiest way to preserve the catch of the day.
The inland trout and salmon season starts the last Saturday of April and finishes September 30th each year. For Michigan residents the fishing license fee is $26.00. Anyone over the age of 17 years needs a license to fish in the state of Michigan. The license may be purchased from a variety of locations as well as on line.
Although many people prefer to freeze their fresh catch, freezing, as a method of preservation, is only as good as the quality of the product to start with. Precautions need to be taken to guard against flavor and textural changes. For this reason, the fish should be handled in such a way to preserve the fresh quality.
When fresh fish is frozen, the processes of spoilage is temporarily stopped. First, the freezing temperatures stop the growth of bacteria in and on the fish. The bacteria are the primary reason that fish spoil so quickly. However, when the temperature of the fish rises above freezing the bacterial growth will start again.
Cold temperatures slow down the activity and reaction time of enzymes in the gut and tissues of the fish. The primary enzyme activity that slows down is the digestion of food in the fish’s gut and the process involved in tissue and cell maintenance. These enzymes continue to work even though the fish is dead, which causes tissues to breakdown and off-flavors and aromas to develop.
How the fish is handled from the time it is hooked and pulled from the water has a major impact on the quality, taste, and freezer storage life of the fish.
Do not allow the fish to flop around in the boat because this causes bruising of the flesh and results in defects in the frozen product.
The fish should be cleaned and gutted as soon as it is caught. However, if this is not possible, a cooler with plenty of ice should be waiting for this fresh caught fish. There should be a false bottom in the bottom of the cooler so the melted ice water drains away from the fish. The fish should not be allowed to float in the ice water because the flesh will absorb water having an impact on the flavor and texture of the fish. If there is no false bottom and the trip home is long, it will be necessary to stop on the way home to drain off the water.
For cleaning the fish, it will be necessary to have a sharp knife and lots of clean water.
Michigan State University Extension recommends washing your hands before and after working with the raw fish to prevent the transmission of food borne illness bacteria. Wash the fish to remove any soil and excess slime. Remove the scales by gently scraping the fish from tail to head with the dull side of a knife or a spoon. To remove the entrails, cut the entire length of the fish from the vent to the head. Remove entrails. Cut off the head.
Remove the dorsal or large back fin by cutting along each side of the fin and pulling it out. Do not trim the fins with shears because this will leave the bones at the base of the fin behind in the flesh.
Wash the fish thoroughly with cold running water. Large fish can be cut into steaks and fillets for easier cooking.
In preparation for freezing, fish are categorized as either fat or lean, which is determined by the amount of fat on the flesh. “Fat fish” are the varieties of mackerel, trout, salmon, and tuna. Most freshwater fish is considered “lean”.
Pretreat fish before freezing to preserve to quality of the freezer stored fish. The “fat” fish should be dipped for 20 seconds in an ascorbic acid solution. To make the ascorbic acid solution, use 2 tablespoons of crystalline ascorbic acid to one quart of cold water to control rancidity and flavor change. For lean fish, dip them for 20 seconds in a brine of ¼ cup salt to 1 quart of cold water to firm up the flesh and to decrease the amount of water loss from thawing.
If several fish are going into one package, place freezer paper or wrap between each piece for easier separation.
Methods of packaging fish for freezing:
Lemon-gelatin glaze method:
Mix 1/4/cup lemon juice and 1 ¾ cups of water. Dissolve one packet of unflavored gelatin in ½ cup of the lemon-juice water mixture. Heat the remaining 1 ½ cups of the lemon-water liquid to boiling. Stir the dissolved gelatin mixture into the boiling liquid. Cool to room temperature. When cool, dip the cold fish into the lemon-gelatin glaze and drain. Wrap the fish in moisture-vapor resistant packaging, label and freeze.
Ice glaze method:
Place unwrapped fish on a cookie sheet in the freezer to freeze. As soon as it is frozen, dip fish in near-freezing ice water. Place fish again in the freezer for a few minutes to harden the glaze. Take fish out, and repeat glazing until a uniform cover of ice is formed. Wrap the fish in moisture-vapor resistant paper or place in a freezer bags, label and freeze.
Place fish in a shallow metal, foil, or plastic pan; cover with water and freeze. To help prevent evaporation of the ice, wrap the container in the freezer paper after it is frozen. Label and freeze. Freezing fish in a block of ice will produce a poorer quality of product than the glazing methods.
With proper care to package, the salmon and trout (fatty fish) can be stored for at least three months in the freezer before quality starts to deteriorate.
With a little planning, those freshly caught salmon or trout can be frozen to preserve the quality, flavor and texture.
For further information, contact your local county MSU Extension office.