How to keep your meat safe, delicious

Last night I left cooked roast beef on the counter to cool before refrigerating but fell asleep and discovered it this morning. I immediately put it in the refrigerator. Since the meat is cooked, shouldn't it be safe to eat?"

The answer to this question is that the roast beef should be thrown out. Why? Because leaving food out too long at room temperature can cause bacteria, such as Staphylococcus aureus, Salmonella enteriditis, Escherichia coli O157: H7 and Campylobacter, to grow to dangerous levels that can cause illness.

Bacteria are everywhere. They are in the soil, air, water and the foods we eat. When the bacteria have nutrients (food), moisture, time and favorable temperatures, they grow rapidly, increasing in numbers to the point where some can cause illness. Understanding the role temperature plays in keeping food safe is critical. If we know the temperature at which food has been handled, we can then answer the question, "Is it safe?"

THE DANGER ZONE (41 TO 135 DEGREES)

Bacteria grow most rapidly in the range of temperatures between 41 and 135 degrees, doubling in number in as little as 20 minutes. This range of temperatures is often called the "danger zone." That's why perishable foods should never be left unrefrigerated more than two hours. If the temperature is above 90 degrees, food should not be left out for more than one hour.

COOKING

Raw meat and poultry always should be cooked to a safe internal temperature. When roasting meat and poultry, an oven temperature no lower than 325 degrees should be used. Use a meat thermometer to ensure the food has reached a safe internal temperature.

Cook beef, veal and lamb steaks, roasts and chops to a minimum internal temperature of 145 degrees for medium rare, 160 degrees for medium and 170 degrees for well-done. Cook pork to 160 degrees. Cook ground meats to an internal temperature of 160 degrees and ground poultry to 165 degrees. All poultry is safe if it reaches an internal temperature of 165 degrees. For personal taste preferences, poultry may be cooked longer.

If raw meat and poultry have been handled safely, using the above preparation recommendations will make them safe to eat. If raw meats have been mishandled, bacteria might grow and produce toxins, which can cause foodborne illness. Cooking does not destroy heat-resistant toxins; therefore, even though cooked, meat and poultry mishandled in the raw state may not be safe to eat even after proper preparation.

STORING LEFTOVERS

One of the most common causes of foodborne illness is improper cooling of cooked foods. Bacteria are everywhere, even after food is cooked, and they can be reintroduced to the food and then reproduce. For this reason, leftovers must be put in shallow containers for quick cooling and refrigerated immediately or within two hours of preparation.

REHEATING

Foods should be reheated until hot and steaming, and to an internal temperature of 165 degrees. In the microwave, cover food and rotate so it heats evenly. Follow manufacturer's instructions for stand time for more thorough heating. In the absence of manufacturer's instructions, at least a two-minute stand time should be allowed.

COLD STORAGE TEMPERATURES

Properly handled food stored in a freezer at zero degrees will always be safe. Freezing keeps food safe by slowing the movement of molecules, causing bacteria to enter a dormant stage. Once thawed, these bacteria can again become active and multiply to levels that may lead to foodborne illness. Because bacteria on these foods will grow at the same rate as they would on fresh food, thawed foods should be handled as any other perishable food.

A temperature of 34 to 40 deegrees should be maintained in the refrigerator. Perishable foods will gradually spoil in the refrigerator. Spoilage bacteria will make themselves known in a variety of ways. The food might develop an uncharacteristic odor, color or become sticky or slimy. Molds might also grow. Bacteria capable of causing foodborne illness either don't grow or grow very slowly at refrigerator temperatures. A refrigerator/freezer thermometer should be used to verify the temperature of the unit is correct.

Safe food-handling practices are a good defense against foodborne illness. Because we know how different temperatures affect the growth of bacteria in our food, we can protect ourselves and our families by proper handling and cooking, and by storing foods at safe temperatures.

Bob Guinn is Beaufort County Clemson University Cooperative Extension Service home economics and community development senior agent. Contact him at 843-470-3655, ext. 116, or rguinn@exchange.clemson.edu.