Tips on buying fresh fish:
Whole Fish
Look for bright, clear eyes. The eyes are the window to a truly fresh fish, for they fade quickly into gray dullness. Dull-eyed fish may be safe to eat, but they are past their prime.
Next look at the fish. Does it shine? Does it look metallic and clean? Or has it dulled or has discolored patches on it? If so, it is marginal.
Smell it. A fresh fish should smell like clean water, or a touch briny or even like cucumbers. Under no circumstances should you buy a nasty smelling fish. Cooking won't improve it.
Look at the gills. They should be a rich red. If the fish is old, they will turn the color of faded brick.
Fish Fillets
Look for vibrant flesh. All fish fade as they age. If the fillet still has skin, that skin should look as pristine as the skin on an equally good whole fish – shiny and metallic.
Smell it. The smell test is especially important with fillets. They should have no pungent aromas.
Is there liquid on the meat? If so, that liquid should be clear, not milky. Milky liquid on a fillet is the first stage of rot.
If the fishmonger lets you, press the meat with your finger. It should be resilient enough so your indentation disappears. If your fingerprint remains, move on.
Best fish to grill:
Thick steaks, such as tuna, swordfish, mahi-mahi and salmon fare well on a grill. But don't discount whole fish like trout, red snapper, striped bass and bluefish. They work well, too, if you can get past the eyes and tail!
Tender fillets like sole, catfish, flounder and tilapia don't do as well on a grill, because they tend to break up and fall through the grate. You can grill more fragile fish in a foil packet or using a wire fish basket. Otherwise, save these kinds for pan cooking, baking or deep frying.
Fish Grilling Methods
Grills: Whether using gas, charcoal, electric or grill pans, there’s a secret to grilling fish: Get your grill as hot as you can make it. You want to sear the fish as soon as it hits the grate. This seals in the juices and immediately firms the flesh; it's less likely to stick to the grate and it's easier to flip.
Cedar smoking/grilling is a no-fuss way to grill tender fillets, salmon and shrimp. The fish or shrimp are cooked on a wood plank, which gives them a smoky flavor. Just presoak the cedar plank, arrange your fish on top, cover and grill.
Foil Packet Grilling: There will be occasions when you want to cook a more delicate fish, and this is the perfect time to use foil packets. This is also a great way to cook an entire meal, because you can cover the fish (or meat) with vegetables and potatoes. Basically, you lay the fish (and anything else you want to cook) on a piece of foil, then bend the foil over top and seal all the sides by folding them over several times.
