To avoid food poisoning from a harmful strain of E. coli bacteria, consumers should cook meat until medium- or well-done and never handle cooked meat with utensils used with raw meat, warns a UC Davis meat scientist. "Steaks are normally not contaminated, because they come from inner muscle, and if there is contamination it usually is limited to the surface, which is cooked," says Yu-Bang Lee, a professor of animal science and an authority on meat processing. "Hamburger poses a major problem, however, because meat from all parts of the carcass is ground up in it. E. coli can still be present if the meat is contaminated and improperly cooked." E. coli bacteria live in the intestinal tract of animals, becoming a problem only if the intestines rupture or the carcass is mishandled during slaughter and processing, Lee says. Most cases of E. coli poisoning are linked to beef, probably because consumers tend not to cook it as well as they do poultry and pork. Some salami meat is never cooked, merely ground, spiced, acidified, cured and dried, according to Lee. This process arrests the growth, but doesn't kill, microorganisms such as the harmful strain of E. coli that may be present, he says.