Most of us cook a bit too much and save the rest for later. Leftovers are a handy way to cut food waste and get a quick lunch the next day. They can also make you sick if they sit out too long or get stored the wrong way. A few simple habits make a big difference.
This guide covers how to cool, store and reheat leftovers at home. It draws on advice from Australian state health and food safety agencies. The rules are easy to follow once you know the reasons behind them. Most come down to time and temperature.
Why time and temperature matter
Food poisoning bacteria grow best between 5°C and 60°C. Food safety agencies call this range the temperature danger zone. Cold food should stay at 5°C or below and hot food should stay above 60°C. The longer food spends in between, the more chance bacteria have to multiply.
The time adds up, too. NSW food safety advice explains that the time spent between 5°C and 60°C is cumulative. So the half hour on the bench while you serve dinner counts. So does the time in a warm car on the way home from a barbecue.
You also cannot rely on your nose. Food safety and storage advice from the Victorian Government notes that contaminated food may look, smell and taste normal. A dish that seems fine can still carry enough bacteria to make you unwell. That is why the timing rules matter more than a quick sniff test.
The 2 hour and 4 hour guide
A simple rule of thumb helps you decide what to keep. If cooked food has been out of the fridge for less than 2 hours, you can use it now or put it in the fridge for later. Between 2 and 4 hours, use it straight away rather than storing it. After more than 4 hours out, throw it away.
Food Standards Australia New Zealand sets out this 2 hour and 4 hour rule as a guide for food businesses. The same thinking works well in a home kitchen. Keep an eye on the clock at parties, picnics and family lunches. If you are not sure how long something has been sitting out, it is safer to bin it.
Cooling leftovers the right way
The aim is to get cooked food cold quickly. NSW advice is to cool and cover leftovers and put them in the fridge or freezer within 2 hours. Splitting a big pot into smaller portions helps it cool faster. Shallow dishes work better than deep ones for the same reason.
Better Health Channel suggests waiting until steam has stopped rising before you put food in the fridge. You do not need to leave it on the bench until it is cold. Once the steam stops, it can go straight in. Leaving a large pot of curry or soup out overnight to cool is one of the habits to drop.
Small steps like these are part of looking after your health day to day. Much like the slow and steady changes involved in quitting smoking, good kitchen habits stick best when they become routine. Pick one or two to start with. Then add more as they become second nature.
Setting up your fridge
Your fridge should sit at 5°C or below. A cheap fridge thermometer is the easiest way to check it. Your freezer should be colder than minus 15°C. If either is warmer, adjust the dial and check again the next day.
Where food goes in the fridge also matters. Store raw meat in sealed or covered containers at the bottom. Keep raw foods below cooked foods so juices cannot drip onto them. Cover leftovers with a tight lid, foil or plastic film.
Foods that need extra care
Some foods are more likely to cause food poisoning if they are not kept cold. These are the ones to cool fast and eat soon. Victorian health advice lists the high risk foods below.
- Raw and cooked meat, including casseroles, curries and lasagne
- Dairy products such as custard and cheesecake
- Eggs and egg dishes such as mousse
- Smallgoods such as ham and salami
- Seafood, including seafood salad, patties and stock
- Cooked rice and pasta
- Prepared salads and fruit salads
- Sandwiches, pizzas and other foods that contain any of the above
Cooked rice and pasta deserve a special mention. NSW advice is to eat them within 2 days of cooking, rather than the 3 days allowed for most other leftovers. They should also be reheated only once. If you buy takeaway rice, eat it soon after you buy it.
How long leftovers keep
Leftovers in the fridge should be eaten within 3 days, according to NSW food safety advice. Rice and pasta should be eaten within 2 days. Writing the date on a container lid makes this much easier to track.
Freezing gives you more time. NSW advice says frozen leftovers can be kept for up to 3 months. Thaw them in the fridge rather than on the bench. Once thawed, use them within 24 hours.
Victorian advice adds that raw food should never be refrozen once thawed. If you thaw food in the microwave, cook it straight away. Planning portions before you freeze saves you from thawing more than you need. Smaller containers are handy for single serves and work lunches.
Leftovers make a cheap and easy lunch to take to the office. While you are thinking about healthy work habits, it is worth reading about the health benefits of standing desks. Keep your lunch in the work fridge rather than in your bag all morning. On hot days or longer trips, a cooler bag with an ice pack helps.
Reheating leftovers safely
Reheat leftovers until they are steaming hot all the way through. NSW guidance gives a target of at least 60°C. Microwaves can heat unevenly, so stir the food partway through. Check the middle of the dish before you serve it.
Only reheat what you plan to eat. Heating the whole container and putting the rest back in the fridge adds more time in the danger zone. This matters most for rice and pasta, which should be reheated once only. Serving out a portion first is the simplest fix.
Less waste and a healthier household
Good leftover habits help your budget as well as your health. Food that is cooled and stored well lasts longer, so less ends up in the bin. Cooking once and eating twice also saves time on busy nights. If you are working on your household budget, our post on the health benefits of a financial plan looks at the link between money and wellbeing.
Children can learn these habits early. Packing a school lunch is a good time to show them why the cold pack goes in the bag. Healthy routines for kids go beyond the kitchen, and our post on dental fear in children looks at helping them feel calm at the dentist. Habits learnt young tend to last.
Frequently asked questions
Can I put hot food straight in the fridge?
You can put food in the fridge once the steam has stopped rising. There is no need to wait until it is cold. Split large amounts into smaller containers so they cool faster. Aim to have it in the fridge within 2 hours of cooking.
How long can leftovers stay in the fridge?
Most leftovers should be eaten within 3 days. Cooked rice and pasta should be eaten within 2 days. Label containers with the date so you know when they were made. If in doubt, throw it out.
Is it safe to reheat leftovers more than once?
NSW advice is to reheat rice and pasta once only, until steaming hot. For other dishes, reheating each portion just once is the safer habit. Take out the portion you need and leave the rest in the fridge. This keeps the rest of the dish out of the danger zone.
This article is general information only and is not medical advice. Food safety guidance can vary between states and may change over time. If you think you have food poisoning or have concerns about your health, speak with a doctor or qualified health professional. Your local council or state health department can also help with food safety questions.