USDA Advises Consumers to Use a Thermometer When Cooking Hamburger

Washington, June 10, 1997—The U.S. Department of Agriculture today advised consumers to use a meat thermometer when cooking hamburger—and not rely on the internal color of the meat—to be sure that it is safe to eat. To be safe from harmful bacteria such as E. Coli 0157:H7, ground beef must be cooked to 160 degrees Fahrenheit.

USDA’s Food Safety and Inspection Service (FSIS) said the emphasis on using a meat thermometer results from research that indicates some ground meat may turn prematurely brown before a safe internal temperature of 160 F has been reached.

"New research shows that the phenomenon of premature browning may be more prevalent than originally thought, and may occur under normal consumer handling conditions," said Thomas J. Billy, administrator of FSIS. "FSIS is conducting a survey and risk assessment to confirm and extend observations on the premature browning effect. In addition, FSIS will convene an open meeting in the near future to call for additional research and to discuss all of the issues surrounding safe cooking of hamburger," Billy said.

FoodNet, the foodborne disease surveillance system sponsored by the Center for Disease Control and Prevention, the Food and Drug Administration, and FSIS, is analyzing data from E. Coli 0157:H7 case-control studies to determine risk factors for the illness. Initial data from the Minnesota State Health Department has shown that there is an association of the illness with the consumption of hamburgers prepared in the home that are pink on the inside.

"However, we are aware of other research findings that show some ground meat patties safely cooked to 160 degrees Fahrenheit or above, may remain pink in color for a variety of reasons," Billy said. "In the fact of this new research and seemingly conflicting data and viewpoints, FSIS alerts consumers that the color of meat is no longer considered a reliable indicator of ground beef safety. A meat thermometer is the most reliable way to reduce the risk of foodborne illness."

Susan Conley, director of FSIS’s Food Safety Education and Communications Staff, offers these additional tips for thermometer use:

• Use an "Instant-read" thermometer to check patty temperatures. They are designed to be used toward the end of the cooking time and register a temperature in about 15 seconds.
• Check the stem of the instant-read thermometer for an indention that shows how deep July 17, 2008ading. Most digital thermometers will read the temperature in a small area of the tip. Dial types must penetrate about 2 inches into the food.
• The meat thermometer should penetrate the thickest part of the hamburger.
• If a beef patty is not thick enough to check from the top, the thermometer may be inserted sideways.
• To check the thermometer calibration, place the stem into a cup of boiling water. If correct, it will read 212 F. Most thermometers have a calibration nut under the dial that can be adjusted.
• In addition to the recommended 160 F internal temperature for ground meat, the following safe temperatures are advised for these other foods:
  • Beef roasts, steaks, and chops should be cooked to 145 F for medium rare; 160 F for medium, and 170 F for well-done.
  • Pork roasts, steaks and chops should be cooked to 160 F for medium, and 170 F for well-done.
  • Whole chicken or turkey should be cooked to 180 F. Breasts should be cooked to 170 F.
• Be sure to wash the thermometer after each use.

For further food safety information, call the USDA’s nationwide, toll-free Meat and Poultry Hotline at 1-800-535-4555. Specialists are available Monday-Friday, from 10 a.m. to 4 p.m., Eastern Time. In addition, timely food recorded food safety messages are available 24 hours a day, 7 days a week. Visit the FSIS WebSite at: http://www.usda.gov/fsis.