Filleting a fish produces a bone-and skin-free piece of meat that's easy to cook and store. Most fish can be filleted easily, from small panfish like perch to huge saltwater fish like grouper.
Fish taste different in different waters and sometimes a bad flavor from their environment, and even pollutants, can concentrate in the skin. It's often best to remove skin and bones from fish when cleaning them, and filleting is a good way to do this.
How to Fillet a Fish
To fillet a fish you need a sharp thin-bladed knife and a flat work surface. You can buy a good fillet knife, keep if very sharp, and use it for nothing but filleting fish. The point as well as the blade should be sharp. A board two feet long and twelve inches wide works well and you can wash it easily after use.
Many people use an electric knife for filleting fish. The electric knife works well, stays very sharp, and since the blades are removable it cleans up very easily. You don't need a sharp point on an electric knife because the blade slices right through scales and bones.
Filleting a fish
Step one: Lay the fish on the board and make a cut just behind the gills across the body down to the backbone. On a small fish this cut will cross the whole body; on a bigger fish you will need to move your knife to make a complete cut. Be careful you don't cut through the backbone, especially when using an electric knife.
Step two: With smaller fish you can turn the blade of the knife and follow the backbone all the way to the tail, skipping steps two and three. With bigger fish make a cut along the top of the backbone with your knife, following it all the way to the tail. This cut will guide your knife and make it easier to cut the fillet off the fish.
Step three: Make a similar cut along the belly of the fish, staying above the anal fin. Keep your knife parallel to the board and run the point of the knife right along the bottom of the backbone. Continue this cut past the ribs.
Step four: Make a cut from the head of the fish all the way to the tail, cutting through the ribs where they attach to the backbone. For a skinless fillet you should stop just before cutting through the skin at the tail. Flip the fillet over and, holding the tail, run the knife between the skin and meat starting at the tail; then remove the skin. Turn the fish over and repeat the process on the other side.
For a boneless fillet, cut out the rib cage by running the point of your knife along the top of the ribs at an angle, cutting them away from the meat of the fillet. There's very little meat on the ribs of smaller fish.
After the Filleting Is Done
Boneless, skinless fillets are easy to cook or freeze. You can cook them immediately for the best flavor or refrigerate them for a couple of days in a plastic zipper bag filled with salt water. Put the fillets in the bag, add a tablespoon of salt, some water, and then squeeze the air out as you close the bag. Be sure to rinse the salt water off them before cooking.
You can use the same process for freezing but don't add the salt. They will keep for a year, but the longer you keep fish the less flavor they have, so use frozen fish quickly.