Storing leftovers appropriately after a meal is essential to avoid getting sick, as excess bacterial growth may lead to food poisoning.
However, you may wonder whether it’s best to immediately place hot leftovers into the refrigerator.
This article explains whether it’s safe to refrigerate leftovers while they’re still hot.
Bacteria can grow on your leftover foods if you leave them out for too long. As such, you may want to reduce this risk by immediately placing your hot leftovers into the fridge (
The U.S. Department of Agriculture (USDA) advises that small amounts of hot foods may be immediately and safely placed into the fridge (2).
Small amounts of food may include single servings of foods, or enough to fill small plasticware or glassware containers.
However, it’s unclear whether placing larger amounts of hot foods in the fridge is safe.
Large dishes of hot leftovers may heat the surrounding foods, placing them in the temperature danger zone and increasing your risk of foodborne illness.
More research is needed to determine how long refrigerators take to restore the safe internal temperature of hot leftovers and whether significant bacterial growth occurs in the meantime.
The USDA advises that small amounts of hot foods may be immediately placed in the fridge, but more research is needed on whether large dishes of hot leftovers can be safely refrigerated.
Although most people are aware that food safety and hygiene are important to prevent food poisoning, 50–87% of foodborne illnesses are linked to eating food at home (
Plus, poor food handling, such as improper refrigeration practices, is associated with an increased occurrence of food-related digestive illnesses (
Studies have shown that those who practice good food hygiene have leftovers with less bacterial growth and fewer occurrences of food poisoning (
The Centers for Disease Control and Prevention (CDC) advises that foods shouldn’t be left for long periods at room temperature or within the range of 40–140°F (4–60°C) — the temperature “danger zone” that facilitates the rapid growth of bacteria in food (
Safe refrigeration temperatures of 40°F (4°C) or colder keep chilled foods safely outside of this danger zone.
These findings reiterate the importance of food safety and appropriate refrigeration for leftover foods.
Implementing safe food practices and appropriate refrigeration techniques keeps foods outside of the temperature danger zone, reducing bacterial growth in food and your risk of foodborne disease.
The USDA’s food safety guidelines state that hot leftovers should be refrigerated within 2 hours after cooking or removal from a cooking device — and 1 hour if the temperature is above 90°F (32°C) (6).
On average, leftover foods may be refrigerated for 3–4 days or frozen for 3–4 months (6).
Here are other ways you can ensure that your leftovers will be safe to eat (7):
- Cook safely. It’s important to cook meat and fish to their appropriate internal temperatures to avoid bacterial growth during storage.
- Cool rapidly. To get your hot leftovers to refrigeration temperatures of 40°F (4°C) quickly, use an ice bath to cool soups, cut large items of food into smaller pieces, and store foods in shallow containers.
- Wrap well. Store leftovers in airtight containers or cover them to avoid bacterial growth and keep odors from other foods out.
- Use the top shelf. Store your leftovers on the upper shelves of the fridge, making sure to eat the dishes you refrigerated earliest to avoid food spoilage and waste. Keep older leftovers at the front and fresher ones toward the back.
To safely store hot leftovers, rapidly cool them, divide them into smaller containers, and refrigerate them within 2 hours of cooking. Refrigerate them for 3–4 days.
Safely storing hot leftovers prevents the growth of bacteria in food and reduces your risk of foodborne illness.
Although the USDA advises that small amounts of hot foods can be immediately placed in the fridge, it’s unclear whether refrigerating large amounts of hot leftovers is harmful.
As such, large dishes like soups, casseroles, and stews should be allowed to cool first, then refrigerated within 2 hours of cooking.