Successful seafood grilling depends on the fish's texture. You want fish that has a thick, firm, meaty texture so that it won't fall apart while it's cooking. Although some of the firm–textured fish is higher in fat than more delicate types of fish, the fat in fish is a kind of heart–healthy fat.
Seafood That Can Take the Heat:
Grouper: This white–meat fish is sold in fillets and steaks. If you can't find grouper, you can use sea bass or mahimahi.
Halibut: The meat of this fish is white and mild–flavored and comes in steaks and fillets. It's a bit more delicate than some of this other fish in this list, so be careful when you're turning it on the grill.
Salmon: With a range of flavors from rich to mild, salmon can take on a char and still keep its distinct taste. You can buy salmon in either steaks or fillets.
Scallops: There are two groups of scallops–bay and sea. The larger sea scallops are best for grilling because they have a meatier texture and can be easily skewered.
Shrimp: Large or jumbo shrimp are the best for grilling. They cook quickly and are easily skewered.
Swordfish: The mild fish has a firm, gray-white flesh and a meaty texture and is usually sold as steaks. Its natural oil content keeps it moist while grilling.
Tuna: If you're new to grilling fish, fresh tuna is a good place to start. It cooks more like beef and its deep red meat almost never sticks to the grill.
Checking for Doneness
To avoid overcooking fish, it's generally best to go with a medium–hot fire rather than a really hot one. You should start checking the fish several minutes before you think it's done. There are two ways to test doneness: (1) pull a little of the flesh out with a fork and see if it flakes, or (2) make a small slit in the thickest part of the fish with a sharp knife. Cooked fish will be firm to the touch and opaque; undercooked fish will appear shiny and semi-translucent.
Tips for Grilling Fish
• Make sure the grill rack is very clean. Any residue on the rack could interfere with the fish's delicate flavor, plus, a clean rack helps prevent sticking.
• Lightly coat the grill rack with cooking spray or brush it with oil before placing it over the heat source. This keeps the food from sticking and makes the grill rack easier to clean.
• Place the seafood on a hot grill rack and leave it there for several minutes before you try to move it. This way, a sear will develop between the fish and the grill rack, and this prevents further sticking.
• Watch the time. Seafood cooks quickly and you don't want to overcook. The cooking time will depend on the thickness of the fish as well as its texture, but most fish cooks in about 10 minutes or less.
• If you have a grill basket, use it for grilling more delicate types of fish such as catfish. With a basket, you turn the whole basket over instead of turning individual pieces of fish, so you don't have to worry about tearing the fish or about small pieces falling through the grill rack. Click here to watch a video on Using a Grill Basket.
The Right Fire for the Fish
To get the best results when you're grilling seafood, be sure to use the right level of heat for the food. Here's what we've found works best.
Medium-High Heat: most fish and shellfish
High Heat: Salmon fillets and steaks; Scallops; Shrimp (peeled)
Sear on High Heat/Finish on Medium Heat: Tuna steaks