Answering Your Questions on E. coli

Herb Gantz

The Meat and Poultry Hotline has received hundreds of calls from consumers about the E. coli 0157:H7 organism and how to avoid it at home. Here are some of the most-often-asked questions the Hotline has received since the outbreak made headlines earlier this year.

To what internal temperature should ground beef be cooked to destroy E. coli?

Cook the ground beef to at least 160ºF. If possible, use a meat thermometer to check that it's cooked all the way through. Otherwise, check visually--red meat is done when it's brown or gray inside. Juices should run clear with no traces of pink.

Is it more risky to eat a rare hamburger than a rare steak or roast?

Yes. Undercooked hamburger is more risky because of the kind of handling and preparation hamburger receives. Surface bacteria may be spread throughout the meat during grinding. Also, ground meat is often made with trimmings from several cuts. But this does not mean that we recommend eating other cuts raw or rare either. You should cook ALL meat, poultry and fish to at least 160ºF.

What are the symptoms of E. coli food poisoning?

Symptoms include severe abdominal cramps, followed by watery diarrhea that often becomes bloody. Victims may also suffer vomiting and nausea, accompanied by low-grade fever. In some persons, particularly children and the elderly, the infection can lead to severe complications, including kidney failure.

How do you prevent illness from this serious form of E. coli?

Thorough cooking destroys the E. coli bacteria. In addition, you should follow these general safe food handling tips:

After shopping, quickly freeze or refrigerate all perishable foods. Never thaw food on the counter or let it sit out of the refrigerator for more than 2 hours. Food should not be off refrigeration over 1 hour in high summer heat (85ºF and above). Use refrigerated ground meat and patties in 1-2 days; frozen meat and patties in 3-4 months. Wash hands, utensils and work areas with hot soapy water after contact with raw meat and meat patties, to avoid cross-contamination. Follow good personal hygiene rules, especially after using the bathroom. Cook hamburgers, other meat patties, meat loaf, meat balls (or any sidedish made with ground meat) until gray or brown inside, or to an internal temperature of 160ºF. Serve food with clean plates and utensils.

How can I tell if the ground beef I buy is safe to eat?

You can't just by looking at it or smelling it. That's why you should always follow the rules mentioned above. If an off-odor is apparent, return it to the store.

Is E. coli a problem only with beef?

No. E. coli can appear in raw milk, so only use pasteurized product. Unprocessed apple cider and unchlorinated water can carry the bacteria from raw meat juices--for example if salad vegetables were chopped on the same cutting board where you had just tenderized steak.

What should I do when eating out in a restaurant or fast food establishment?

Send back any meat, poultry or fish product that does not appear thoroughly cooked. Ground meat should be gray or brown in the center. Poultry juices should run clear and fish should "flake" with a fork. All cooked food should be served hot.

Does freezing kill E. coli?

No! That's why it's important to cook all food thoroughly.

What is USDA doing about the E. coli problem?

USDA has embarked on a number of new initiatives at the farm, meat plant, supermarket and consumer level in order to protect the public. For example, USDA is sponsoring research aimed at keeping food animals from harboring the 0157 bacteria in their systems, which includes efforts to develop a vaccine against the illness. We are working on improved detection methods to keep the bacteria out of meat plants. We are instituting more stringent time and temperature controls in meat processing plants like those that produce hamburger. We are working closely with state and local public health agencies to increase their effectiveness in avoiding and containing outbreaks, and we will soon require that all raw and partially-cooked meat and poultry products have safe handling instructions on the package. These safe handling directions will cover proper cooling and cooking.

  1. This document is a Summer Supplement reprinted from "Food News For Consumers," U.S. Department of Agriculture. Publication date: 1993.
  2. Herb Gantz, author for "Food News For Consumers," U.S. Department of Agriculture, Food Safety and Inspection Service.