We ate out this weekend, and I got a take-home container for my leftovers. On the way home, we stopped at a store and were there much longer than we anticipated. By the time we got home, it was three hours since we had been served at the restaurant. We refrigerated the leftovers, but should we throw them away instead?
Yes, it’s a good idea to pitch them.
Food safety authorities recommend throwing away food items that have been left out for more than two hours, or for more than one hour if the surrounding air temperature is 90 degrees or above.
At those temperatures, harmful microorganisms can multiply rapidly and can easily get to a point where they can cause illness. Reheating the leftovers would kill bacteria, but some types of organisms that cause foodborne illness can actually produce toxins that don’t go away even if you thoroughly heat the food.
Some people are more susceptible to foodborne illness and need to be especially careful, including:
- Seniors, because the immune system weakens with age, making it more difficult to combat illness from bacteria and other pathogens. Also, stomach acid tends to decrease with age, which means less is available to reduce bacteria in the intestinal tract.
- Young children, whose immune systems are still developing.
- Pregnant women, whose immune systems are altered by the pregnancy. Foodborne illness during pregnancy can not only make the mother ill but can lead to miscarriage, premature delivery, stillbirth, or sickness or death of the newborn baby.
- People with chronic illnesses, including diabetes. They also have weakened immune systems that could exacerbate problems from foodborne pathogens. People with diabetes are also more likely to have problems with their kidneys, which may hold onto harmful bacteria and other pathogens longer than normal. People with cancer or HIV/AIDS and transplant recipients also need to be especially vigilant.
Even when properly handled, use leftovers within three or four days. It’s always a good idea to label the container with the date to help you remember. When reheating leftovers, make sure they get steaming hot -- 165 degrees F throughout. Use a food thermometer. Soups, sauces, gravies and other liquids should be reheated to a boil.
Chow Line is a service of Ohio State University’s College of Food, Agricultural, and Environmental Sciences and its outreach and research arms, Ohio State University Extension and the Ohio Agricultural Research and Development Center. Send questions to Chow Line, c/o Martha Filipic, 2021 Coffey Road, Columbus, OH, 43210-1044, or firstname.lastname@example.org.
Editor: This column was reviewed by Linnette Goard, field specialist in Food Safety, Selection and Management for Ohio State University Extension, the outreach arm of the College of Food, Agricultural, and Environmental Sciences.
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OSU Extension, Food Safety, Selection and Management