I take a rather blithe approach to eating raw things from the sea, so if it looks and smells okay I go ahead and eat it. But occasionally salmon, especially wild salmon, may have parasites, and salmon that has been carelessly handled may have bacteria on its surface. I avoid the bacteria problem by only buying salmon from a clean fish store and handling the salmon carefully when I get it home (I clean my cutting boards, knives, and hands with hot water with bleach in it. If the bleach leaves your hands feeling slippery, rub them with vinegar.) Parasites are more difficult to kill because they live inside the salmon flesh. Experts recommend freezing salmon to be eaten raw, cold smoked, or cured, at -4° F for 7 days. If you’re freezer isn’t cold enough, buy salmon from someone you can trust and make sure it has been deep-frozen—ask for “frozen at sea” salmon, sometimes called FAS—or wrap it tightly in plastic wrap and aluminum foil in the freezer for 3 days.