My husband and I do a lot of cooking on the weekend so we just have to reheat leftovers for dinner later in the week. But we have a question: When we make a big pot of chili or soup, should we let it cool on the counter before refrigerating it, or not?
Letting foods cool at room temperature is risky. But so is putting a large, bulky container of hot food into the refrigerator.
The trick is to make sure the food cools as fast as possible, so it quickly passes through the “danger zone” (between 40 degrees and 140 degrees F). That’s the temperature where any microorganisms that might be lurking in your culinary creations can multiply rapidly.
The time limit for food to be in the danger zone is two hours. But a large container of hot food can take eight hours to cool below 40 degrees F, even when you put it in the refrigerator. That’s much, much too long.
Your best bet, food safety experts say, is to put hot cooked food into shallow containers. Make sure the food isn’t more than 2 inches deep. Then refrigerate at once. (Put potholders beneath hot containers to prevent the heat from cracking a glass shelf.) Similarly, a whole roast, ham or turkey should be sliced or cut into small pieces before refrigerating.
Many food safety guidelines say to store leftovers no more than three to four days in the refrigerator. That builds in a margin of safety for at-risk populations, including children, the elderly, pregnant women or anyone with a chronic illness. For the general population, the Food and Drug Administration’s Food Code, designed for retail and food-service establishments, allows seven days for leftovers to be safely refrigerated at 41 degrees F or below.
- Reheat leftovers to 165 degrees F for at least 15 seconds.
- Reheating in a microwave oven can allow cool pockets to form. Be sure the food rotates for more-even heating. Or, stir the food after it heats, and let it sit covered for two minutes before serving.
- Put a date on leftovers. Don’t assume you’ll remember how long they’ve been in the refrigerator.
- Bring leftover gravy and sauce to a rolling boil before serving.
- Place items in your refrigerator with care. To chill food properly, cold air must be able to circulate.
- Consider freezing leftovers you won’t be able to consume within a few days to a week.
- Don’t rely on the “smell test” to determine if old leftovers are safe. Generally, bacteria that cause illness do not leave any overt telltale signs.
Chow Line is a service of 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 Lydia Medeiros, food safety specialist with Ohio State University Extension, scientist with the Ohio Agricultural Research and Development Center, and professor of human nutrition in the College of Education and Human Ecology.