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FREEZING

Freezing and Packing Procedure

Fish

Fish for freezing should be as fresh as possible.

Preparation

  • Wash fish, and remove scales by scraping fish gently from tail to head with the dull edge of a knife or spoon.
  • Remove entrails after cutting entire length of belly from vent to head. Remove head by cutting above collarbone.
  • Break backbone over edge of cutting board or table.
  • Remove dorsal or large back fin by cutting flesh along each side and pulling fin out.
  • Do not trim fins with shears or a knife because bones will be left at the base of the fin.
  • Wash fish thoroughly in cold running water.
  • Fish is now dressed or pan dressed, depending on size.
  • Large fish should be cut into steaks or fillets for easier cooking.
  • For steaks, cut fish crosswise into ¾-inch thick steaks.
  • For fillets, cut down back of fish from tail to head.
  • Then cut down to backbone just above collarbone.
  • Turn knife flat and cut flesh along backbone to tail, allowing knife to run over rib bones.
  • Lift off entire side of fish in one piece, freeing fillet at tail. Turn fish over and cut fillet from other side.

Pretreating

  • Fish are categorized as either fat or lean fish, by the amount of fat in their flesh.
  • "Fat fish" includes varieties such as mullet, mackerel, trout, tuna and salmon.
  • "Lean fish" includes flounder, cod, whiting, redfish, croaker, snapper, grouper, sheepshead and most freshwater fish.
  • Before freezing, fish can be pretreated to improve the quality of the stored fish.
  • Fat fish should be dipped for 20 seconds in an ascorbic acid solution made from 2 tablespoons crystalline ascorbic acid to one quart of cold water to control rancidity and flavor change.
  • Lean fish may be dipped for 20 seconds in a brine of ¼ cup salt to 1 quart of cold water to firm the fish and to decrease drip loss from thawing. (These pretreatments are not needed if a lemongelatin glaze is used.)
Packaging

Fish may be frozen using any of the following methods. If several fish are placed in the same package, place freezer paper or wrap between them for easier separation.

  • Lemon-Gelatin Glaze — To prepare glaze, mix ¼ cup of lemon juice and 1¾ cups of water. Dissolve one packet of unflavored gelatin in ½ cup of the lemon juice-water mixture. Heat the remaining 1½ cups of 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 — Place unwrapped fish in the freezer to freeze. As soon as it is frozen, dip fish in near-freezing ice water. Place fish again in the freezer a few minutes to harden the glaze. Take fish out, and repeat the glazing until a uniform cover of ice is formed. Wrap the fish in moisture-vapor resistant paper or place in freezer bags, label and freeze.
  • Water — Place fish in a shallow metal, foil or plastic pan; cover with water and freeze. To prevent evaporation of the ice, wrap the container in freezer paper after it is frozen, label and freeze. Freezing fish in a block of ice will produce a poorer quality product than using the glaze methods.
  • FISH ROE — Thoroughly wash and package in freezer containers or bags and boxes, leaving ¼-inch headspace. Seal and freeze.

Source :

"So Easy to Preserve", 5th ed. 2006. Bulletin 989, Cooperative Extension Service, The University of Georgia, Athens. Revised by Elizabeth L. Andress. Ph.D. and Judy A. Harrison, Ph.D., Extension Foods Specialists.

Updated on : Feb 2015

 

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