Cooling and storing leftovers

Summary

This pattern is for anyone who keeps cooked food for later. It describes how to cool, store and reheat leftovers so they stay safe and you know what’s in the fridge.

Recommendation	Why?
Put cooked food in the fridge as soon as it has stopped steaming, and within 2 hours of cooking.	Bacteria grow fastest between 5 °C and 60 °C, so food shouldn’t sit at room temperature for long.
Divide large batches into shallow containers.	A big pot cools slowly in the middle. Shallow portions get through the danger zone quickly.
Keep your fridge at 5 °C or below and your freezer at about −18 °C.	Cold slows bacterial growth. A cheap fridge thermometer tells you if the setting is right.
Label each container with what it is and the date.	Nobody has to guess, and the oldest food gets eaten first.
Eat refrigerated leftovers within 2 to 3 days, or freeze them.	Some bacteria still grow slowly in the fridge, and you can’t see or smell many of them.
Reheat until steaming hot all the way through, at least 75 °C.	Thorough reheating kills bacteria that may have grown during storage.
Reheat only once, and only the portion you’ll eat.	Each round of cooling and reheating gives bacteria another chance to grow.
When in doubt, throw it out.	Food that’s been left out too long or kept too long isn’t worth the risk.

Context

This pattern suits cooked meals, soups, stews, rice, pasta, and cooked meat and vegetables.

It does not suit food that has already sat out at room temperature for more than 2 hours (Food Standards Australia New Zealand’s 2-hour/4-hour guide says refrigerate or use it within 2 hours, use it within 4, and throw it out after that). Cooked rice needs extra care; see Rinse, measure and rest rice. Be stricter for anyone who is pregnant, elderly, very young or has a weakened immune system.

There’s a trade-off between cooling quickly and protecting the fridge. Putting a large, very hot pot straight into the fridge warms everything else in it. This pattern lets food stop steaming first, then splits it into small containers so it cools quickly without heating the rest of the fridge.

Usage

Cooling: let food stand only until the steam has died down. For large pots, such as a stew from the pressure cooker (see Natural pressure release), spoon the food into shallow containers or stand the pot in a sink of cold water and stir. Leave lids off or ajar until cool, then seal.

Storing: label and date each container and put it on a shelf, not the door, where the temperature is steadier. Keep raw meat below cooked food. Freeze anything you won’t eat within 2 to 3 days, and thaw it in the fridge or microwave, not on the bench.

Reheating: heat until steaming hot throughout and bubbling at the edges, stirring halfway in the microwave. A thermometer takes the guesswork out; see Cook by temperature, not time. Don’t put reheated leftovers back in the fridge.

References

Food Standards Australia New Zealand publishes guidance on safe temperatures, the 2-hour/4-hour rule and handling leftovers, and your fridge’s manual explains its temperature settings.