Rock cod is the market name for rockfish, a saltwater fish native to the Eastern Pacific. This fish is also sometimes labeled as “Pacific snapper” or “red snapper,” capitalizing on consumer demand for that species. Consumers should know that snapper fish do not live off the West Coast of North America, with the bulk of this delicately flavored fish coming from Australia and the East Coast of the United States. A fish which claims to be snapper cannot come from the Eastern Pacific.
Rockfish live in shallow offshore waters, and they come in a variety of shapes and sizes. The types most commonly fished commercially have firm, lean, white flesh that cooks to a flaky texture. It has a very mild flavor, and the meat is quite versatile. The flesh is not quite as tender and slightly sweet as snapper, however, so people are often disappointed when they purchase rock cod which has been inappropriately labeled.
Because this fish is firm fleshed, it is ideal for grilling and frying. It also performs very well in the oven and in the steamer, and the mild-flavored flesh takes flavorings and marinades quite readily. This fish should always be tested to make sure that it is fully cooked before serving. It should have opaque flesh that is also slightly moist.
There are some ecological concerns involved with this fish that conscientious consumers may want to be aware of. Trawled rock cod is not recommended by many seafood advocacy organizations, because trawling can damage the ocean floor and hurt other fish species. Line-caught fish is a reasonably good choice, although because these fish take a long time to mature, populations are very vulnerable to overfishing.
The persistent abuse of labeling in fish markets is also a concern, because purchasers may not be aware of the true identity of the fish they are buying. Fish labeled as “snapper” in many markets are commonly another fish species, and rock cod isn't even a true cod, just to add to the confusion. Fish markets are not always aware of the problems with their labeling, since once a fish has been cut up for sale, it can be difficult to tell what species it is without genetic testing. Consumers who are concerned about truth in fish labeling may want to consider purchasing only whole fish, which are much easier to identify.