If you have food leftover from a weekend roast or a large batch of cooking, there are plenty of leftovers recipes on hand to help you re-use your cooked ingredients. But since half of all reported food poisoning cases are caused by what we’ve eaten at home, it’s important to be careful when cooling, storing and reheating leftovers.
How to store food properly
Christmas leftovers are always popular and with so many elements and people involved it’s especially important to be vigilant at this time of year. If a surplus of food is likely, start cooling what you don’t need quickly – ideally, you’ll get your leftovers into the fridge within 90 minutes. Here’s how:
- Transfer food out of a hot pan, away from the heat source so that it’s not being kept warm through the residual heat.
- If it’s a big quantity, transferring it into a large, shallow dish will help the heat to dissipate. Give thick soups and stews a stir from time to time if necessary.
- Don’t leave foods out for hours or, even worse, overnight.
Food should be thoroughly cooled before putting it in the fridge or freezer, otherwise you risk increasing the temperature in your fridge and creating an environment where bacteria multiply. This could affect your leftovers as well as other foods stored there. Your fridge should always remain below 5ºC. What to do:
- Keep a stash of lidded containers so that you have something to store your leftovers in. Use freezer bags if you don’t have space to store a lot of containers. You can also now buy bags especially for soups and stews.
- Keep your leftovers well sealed and separate. Raw meat and poultry, seafood, eggs, dairy products, pre-packaged food and soft cheeses are among the foods at higher risk of causing food poisoning. Keeping foods separate and well covered helps to combat potential cross-contamination. Take a look at our guide on how to store food.
- If you know you’ll be able to eat the leftovers within two days, pop them in the fridge.
- If there’s a large quantity which you’re unlikely to get through, portion it up and freeze it once cooled, rather than waiting for a few days then freezing it. Take a look at our guide to freezing for handy tips.
When it comes to eating up your leftovers, how you handle them is key to staying healthy. What to do:
- Use up your fridge leftovers within two days.
- If you’re taking leftovers from the freezer, eat within 24 hours. Make sure they’re thoroughly defrosted before heating, by leaving them in the fridge or using a microwave.
- Reheat food until piping hot throughout. If you’re using a microwave, be aware they do not heat evenly throughout, so take your food out halfway through cooking time and give it a stir.
- Don’t reheat leftovers more than once. If you have a big pot of soup, for example, it’s better to take out what you need and reheat it in a smaller pan. Equally, the NHS recommends that you don’t refreeze leftovers. This is because the more times you cool and reheat food, the higher the risk of food poisoning. Bacteria can multiply when cooled too slowly or reheated insufficiently.
- Foods should be heated until they reach and maintain 70ºC or above for 2 minutes.
Foods to be careful of
Some foods, for example those high in protein, may be more prone to causing food poisoning, but the simple rule is that all leftovers need to be cooled quickly, stored properly and eaten within the recommended amount of time.
Having said that, reheating rice is particularly tricky as it can contain a type of bacteria that’s resistant to heat. The longer cooked rice is left at room temperature, the more likely it is that the rice will become unsafe to eat. Ideally only cook as much as you need but if you find you have leftovers, cool within one hour and store in the fridge. Eat within 24 hours, and if you’re reheating it make sure it’s piping hot throughout before serving.
How to avoid food poisoning
Never assume that if something smells ok, that it’s safe to eat. Handling leftovers is only half the story when it comes to steering clear of food poisoning. Take a look at the NHS’ 10 ways to avoid food poisoning and find out more about the other common causes. The Food Standards Agency provides additional information on different types of food poisoning and how to avoid it.
Recipes and tips
It’s easy to create delicious meals from leftovers and best of all it lowers your food waste. Try these recipe collections:
Family dinner ideas for Christmas leftovers
Leftovers recipes: how to avoid food waste
The best leftover chicken recipes
Top 10 ways to use up leftover bread
What to do with leftover lamb
25 ways to use up leftovers
As many countries urge populations to stay at home, many of us are paying more attention to our diets and how the food we eat can support our health. To help sort out the fact from the fiction, BBC Future is updating some of their most popular nutrition stories from their archive.