"The main risk with E.coli is in ground beef," he says. "That's because the meat can become contaminated in the slaughtering process. If you buy a steak contaminated on its surface and you grill the steak, the bacteria get scorched."
Not so with ground beef, Schaffner says. "Here you take a lot of steak, and the bacteria is ground up and mixed in. Now you have a patty with bacteria on the surface and on the interior. That's why we say if you are going to grill a hamburger, you should cook it all the way through -- no red spots and no pink spots."
Food safety specialists at Kansas State University offer the following tips for grilling burgers:
- Start with clean hands, a clean work surface; and fresh meat. Gently shape ground beef into patties and place them on a clean plate or platter. Cover and refrigerate the hamburger patties until ready to cook or grill.
- Defrost frozen patties on a covered plate or platter in the refrigerator. Place the plate or platter on the bottom shelf of the refrigerator to prevent meat juices from dripping on other fresh foods. Thaw frozen patties completely -- partially thawed patties may not cook evenly.
- After handling raw meat, wash hands thoroughly. Clean and sanitize utensils and work surface.
- Cook the hamburger patties over medium heat, or grill them over medium, ash-colored coals. Grill two-inch thick patties 11-13 minutes or until the center reaches 160( F.
- Use a long-handled spatula or grill tongs to turn burgers half way through cooking, and do not press or flatten burgers. Doing so may force out flavorful juices and make the hamburgers taste dry.
- Is it done yet? Use a meat thermometer to check end-point temperature.
- Use a clean spatula or grill tongs to transfer fresh-cooked hamburgers to a clean plate or platter. Do not use the same platter or plate that was used for raw patties unless it has been washed and sanitized.
- Refrigerate leftovers promptly; before serving, reheat completely.
Chicken, too, is likely to be a favorite this weekend. Schaffner says between 10-20% of raw chicken will be contaminated with salmonella, a bacterium that is widespread in the intestines of birds, reptiles, and mammals. The illness it causes, salmonellosis, typically includes fever, diarrhea, and stomach cramps. In people with poor underlying health or weakened immune systems, it can invade the bloodstream and cause life-threatening infections.