Guidelines for Buying Raw Shellfish
Buy only live mollusks. When a clam, oyster, mussel or scallop is alive, the shells will be closed tightly or will close when tapped lightly.
Always ask to see the tag that certifies the shellfish were taken from waters approved by the National Shellfish Sanitation Program, a guide developed in part by the Food and Drug Adminstration. Pollutants in shellfish beds can cause hepatitis, salmonella poisoning and other diseases. In recent years, close monitoring has greatly reduced the danger from pollutants.
Discard dry oyster meat. Oyster meat should have a creamy tan color. The meat should be plump and should smell fresh and mild.