Another difference when cooking fish and seafood is that it does not freeze well—either before or after cooking. The reason is that when food is frozen the liquid inside the cells expand to form ice. This expansion punctures the delicate cell walls, which makes the fish mushy once thawed. So my suggestion is to double or even triple the recipe for the base only. Then freeze the extra portions of base. Thaw it when you come home, add the fresh fish, and within 10 minutes you’ll be enjoying a delicious meal with perfectly cooked fish.
Fish fillets or steaks should look bright, lustrous, and moist, with no signs of discoloration or drying. Above all, do not buy any fish that actually smells fishy, indicating that it is no longer fresh or hasn’t been cut or stored properly. Fresh fish has the mild, clean scent of the sea—nothing more. Look for bright, shiny colors in the fish scales, because as a fish sits, its skin becomes more pale and dull looking. Then peer into the eyes; they should be black and beady. If they’re milky or sunken, the fish has been dead too long. And if the fish isn’t behind glass, gently poke its flesh. If the indentation remains, the fish is old.
It’s more important to use the freshest fish in the market rather than a particular species. All fin fish fall into three basic families, and you can easily substitute one species for another. Use the following table to make life at the fish counter easier.
DESCRIPTION |
SPECIES |
CHARACTERISTICS |
Firm, lean |
black sea bass, cod family, flat fish (flounder, sole, halibut), grouper, lingcod, ocean perch, perch, pike, porgy, red snapper, smelt, striped bass, turbot, salmon, trout, drum family, tilefish |
low-fat, mild to delicate flavor, firm flesh, flakes when cooked |
Meaty |
catfish, carp, eel, monkfish (anglerfish), orange roughy, pike, salmon, shark, sturgeon, swordfish, some tuna varieties, mahi-mahi (dolphin fish), whitefish, pompano, yellowtail |
low to high fat, diverse flavors and textures, usually thick steaks or fillets |
Fatty or strong-flavored |
bluefish, mackerel, some tuna varieties |
high fat, pronounced flavor |
Fish is high in protein and low to moderate in fat, cholesterol, and sodium. A 3-ounce portion of fish has between 47 and 170 calories, depending on the species, and is an excellent source of B vitamins, iodine, phosphorus, potassium, iron, and calcium. The most important nutrient in fish may be the omega-3 fatty acids. These are the primary polyunsaturated fatty acids found in the fat and oils of fish. They lower the levels of low-density lipoproteins (LDL, the “bad” cholesterol) and raise the levels of high-density lipoproteins (HDL, the “good” cholesterol). Fatty fish that live in cold water, such as mackerel and salmon, seem to have the most omega-3 fatty acids.