Storage and reheating basics

Plan the leftovers before serving

Safe leftovers depend on cooling, storage and reheating together. Heat cannot reliably undo poor storage. Decide how much you will eat now and have clean shallow containers ready for the remainder. Keep packaging instructions when using bought food, particularly its use-by date and directions after opening.

The everyday time and temperature checks

• Rice leftovers safelyUse the shorter rice-specific cooling and 24-hour storage routine.

• Keep the fridge between 0 and 5 degrees C. Use a fridge thermometer according to its instructions and check at least weekly; a dial number is not a temperature in degrees. Follow the fridge manual to adjust it and allow it to settle before checking again. Keep the freezer around -18 degrees C. Do not overfill either so that air cannot circulate.
• For most home-cooked food, cool and refrigerate within one to two hours. Eat refrigerated leftovers within 48 hours or freeze them promptly.
• Rice needs a shorter routine: cool ideally within one hour, keep refrigerated for no more than 24 hours before reheating, and reheat only once.
• Defrost in the fridge and use within 24 hours of being fully defrosted, unless specific instructions require otherwise.
• Reheat leftovers only once and make them steaming hot throughout. Warm edges with a cold middle are not enough.

Cool and store a cooked meal

1. Use clean utensils to separate the portion you will save. Do not mix it with food left on somebody's plate.
2. Divide a large batch into small shallow portions so heat can escape; aim for a thin layer rather than filling a deep tub. Stand the containers in a clean cool place, protected from splashes and raw-food contact. Do not stack warm containers together. Start the cooling-time reminder when cooking finishes, not when the food eventually feels cold.
3. Allow the portions to cool, then refrigerate within one to two hours for most food, sooner for rice. If cooling is slow, put the outside of a suitable heatproof container in a cold-water bath, with water below the rim, and stir the food with a clean spoon; keep bath water out of the food. Do not wait indefinitely for a large deep pot to cool. If the storage history is unsafe or uncertain, do not keep it.
4. Once cooled, cover and label with the food name and cooking date and time. Add a use-by reminder: for example, food cooked on Monday at 18:00 should be eaten or already frozen by Wednesday at 18:00 under the normal 48-hour rule, sooner for rice or a stricter instruction. Store ready-to-eat food above sealed raw meat. Do not stack still-warm tubs in the fridge.
5. If freezing, use a freezer-safe container or bag, leave the manufacturer's expansion space for liquids, close once cooled and label the food, cooking date and freezing date. Freeze promptly if you will not use it in the refrigerator window. Freezing does not erase unsafe handling. Keep any earlier reheating history on the label; freezing a reheated meal does not give it another reheating allowance.

Defrost a portion in the fridge

• Use a microwave and check for even heatingUse a defrost program only when you can cook immediately afterwards.

1. Read any product defrosting instructions first. Put the frozen food in a leakproof container or tray; keep raw meat and fish covered on the lowest shelf, below ready-to-eat food.
2. Allow enough time for the centre to thaw fully. Small portions may thaw overnight; large joints can take much longer. Follow the product's timing and do not leave it on the worktop to hurry it.
3. Check for an icy core by separating or inspecting the thickest part as appropriate. Keep chilled while waiting. If the recipe requires fully thawed food, do not start with a frozen centre.
4. Use within 24 hours after fully defrosting, or sooner if the label requires it. Mark when you checked it fully thawed. For a purchased product designed to cook from frozen, follow that complete method instead of partially thawing it.
5. If using a microwave defrost program, follow the food and appliance instructions and cook immediately after defrosting. The microwave lesson explains why defrosting is not a cooking endpoint.

Reheat the portion you will eat

• Use a microwave and check for even heatingFollow cover, stirring, standing and cold-spot checks.
• How to use hob heat without guessingControl heat for the saucepan option.

In a saucepan, add a little suitable liquid if needed to prevent sticking, then heat while stirring so the centre warms too. In a microwave, use a microwave-safe container, vent as directed, stir or turn the food during heating and observe standing time. Follow the appliance and food instructions. Do not use a slow cooker to bring chilled leftovers slowly up to temperature.

For a small portion of soup or sauce in a saucepan, begin over medium-low heat. Add a tablespoon of suitable water or other liquid only if needed to prevent catching. Stir across the base and bring the whole portion to steaming hot, lowering the heat if the base catches before the middle is hot. There is no universal reheating time: quantity, starting temperature and thickness change it. Do not leave the pan while it heats.

For the simple saucepan route, have a clean heat-safe spoon, pan large enough to stir without spilling, tablespoon, serving bowl, dry gloves and trivet ready. Once the whole portion passes the hot-centre check, switch off, put the pan securely on the trivet and serve. Allow your own spoonful to cool before eating. Do not save a partly eaten reheated portion for another reheating.

Check the centre

• Kitchen thermometer basicsCheck the coldest part and hold the required temperature for the full time.

Cut or stir into the thickest area and check that the food is steaming hot throughout. A food probe can check food that needs thorough heating; UK cooking guidance includes 75 degrees C for 30 seconds or 70 degrees C for 2 minutes, held continuously in the coldest checked part. Clean and disinfect the probe before and after use. Avoid repeated cycles of warming a whole container and returning unused food to the fridge.

When to discard instead

Discard food past its use-by date unless it was cooked or frozen safely on or before that date and is still within its separate storage limit. Discard food whose safe storage you cannot establish. A pleasant smell is not proof of safety. If cooling times were badly missed, the fridge failed or food sat out for a prolonged period, do not rely on extra boiling. Consult official guidance for that situation and choose a fresh meal when safety remains uncertain.