Researchers at Kansas State University have found that ground beef browns at different rates, so that browning alone, long considered the primary means of determining ground beef to be cooked, is no longer an accurate indicator of doneness.

"With meats and poultry, the only sure way to test safety and doneness is by using a meat thermometer," says Fadi Aramouni, a Kansas State University Research and Extension food scientist. "Primary food-borne pathogens, including salmonella, campylobacter and E. coli, are heat-sensitive. That means that cooking foods to recommended temperatures will kill any pathogens that may be present."

Summer food safety tips

  • Allow plenty of time to prepare the grill and cook foods completely.
  • Avoid cross-contamination: Use separate plates, platters, bowls, cutting boards and utensils for raw foods and cooked foods.
  • Wait until grilled foods are ready — or almost ready — to eat before removing perishable salads and condiments from the refrigerator or cooler.
  • Wash fresh fruits and vegetables, including leaf lettuce, which can host salmonella.
  • Keep food covered and out of direct sunlight.
  • Clear picnic tables within 60 minutes of serving. Cover and chill leftovers or discard them.
  • Clean grill after each use.
  • Wash hands often, especially before and after handling foods, before and after eating, playing yard games and touching pets. If soap and water are unavailable, an alcohol-based hand sanitizer is a good substitute.

Recommended internal cooking temps

  • Use a meat thermometer to determine doneness. Starting with frozen or partly frozen meat or poultry typically increases the time needed for cooking.
  • Ground beef: 160 degrees
  • Beef, veal and lamb roasts, steaks and chops: Medium: 160 degrees; Well done: 170 degrees
  • Fresh pork: Medium: 160 degrees; Well done: 170 degrees
  • Poultry: 165 degrees or higher