The term whitefish refers to a number of demersal fish species including haddock, cod, pollack, coley and pouting. Some other common examples include grey mullet, turbot, gurnard, hake and pike in addition to ling, brill, lemon sole and sea bass.
Whitefish are also sometimes referred to as lean fish since all the oil is present in the liver and can easily be removed when gutting the fish. Unlike oil-rich fish, whitefish, such as haddock, plaice, and cod, can be stored in a freezer for some time. Black beam, perch and monkfish are other whitefish that are naturally low in fat content and are used as a healthy alternative to oil-rich fishes.