Your fridge freezer and the way you're using it could be mean your food going off more quickly than you'd like. But it's about much more than simply twiddling your thermostat.
If you want to get the most out of your food, the temperature in your fridge needs to be between 0°C and 5°C and the temperature in your freezer needs to be between -18°C and -20°C.
The faster your fridge and freezer get down to these temperatures and the longer they're able to keep them there are key to maximising the amount of nutrients in your food.
Your fridge freezer won't just automatically set to these temperatures. You need to set it up using the manufacturer's recommended setting which you'll find in the instruction manual.
You also need a reliable fridge freezer, as our testing has found that you can't always rely on these settings to work like they should.
The manufacturer's recommended setting on the worst models we've seen sends the temperature in the fridge soaring above 10°C – warm enough to invite heat-loving bacteria inside.
Every degree really does count. The wilted-looking leafy greens in the far right image below had been stored in a fridge for the same time as those in the middle image – just three days.
The difference is that the wilted ones were stored at an average temperature of 6°C, while the fresher-looking ones were at 3°C.
If you're not convinced by the accuracy of your fridge freezer's thermostat, you can pick up a fridge thermometer for less than £10.
No matter how accurate your thermostat is, the temperature in your fridge will still vary between shelves. It's best to think of your thermostat temperature as an average for the fridge because, as a general rule, the higher the shelf, the higher the temperature will be.
But that's no bad thing – provided you use of these different temperatures to get the best out of your food.
Keep middle shelves for:
Leftovers, ready-to-eat foods such as soup, cooked meats and pizza and any fruit that has to be separated from vegetables because of ethylene (see below).
Your fruit and veg will stay fresher for longer if you store them at the correct humidity.
Vegetables tend to like high humidity, while most fruits prefer low.
To see why this is so important take a look at the images below. In the left image you can see the contents of a pack of strawberries and raspberries when new. Then after two weeks half of that same pack stored a low average relative humidity (middle image) and the other half at a high average relative humidity of (right image).
Almost without exception, your fridge freezer won't have been designed to stored in extremely low temperatures (the same goes for very high temperatures, but there's not much risk of that in the UK).
All other fridge freezers are likely to struggle to maintain a safe and stable temperature in these conditions, which won't do your food any favours and could even be unsafe.
Our tests reveal that some models can't even keep a steady temperature when the temperature in your kitchen drops to 10°C on a cold night, or rises to 32°C during a heatwave.
Avoid packing your fridge so full that food on one shelf is touching the shelf above.
This can prevent cool air from circulating, pushing up the temperature in parts of the fridge and inviting heat-loving bacteria to tuck into your food.
As part of our tests, we measure usable volume so you know exactly how much storage space you're actually getting compared to what the manufacturer says you're getting. The worst will give you 34% less storage space than you'd been led to believe.
Keep your food in it's original packaging whenever possible, as it will almost certainly have been designed with food freshness and preservation in mind.
This is especially true of vacuum-packed meat packaging, but also applies to fruit and veg, where strategically-placed air holes can make a big difference to shelf life.
Regardless of whether they're going in the fridge or the freezer, you should always let leftovers cool to room temperature before putting them inside your fridge freezer.
Otherwise, the warmth of your recently-cooked food will send the temperature in your fridge and freezer skyrocketing.
Not only will that reduce the freshness of other food in the fridge – which needs to be kept at a stable temperature – it will also force your fridge freezer to work harder to cool down, pushing up your energy bills.
It's easy to underestimate how much hot air floods into your fridge freezer each time you open the door. This hot air will eat into your food's shelf-life while also edging up your energy bills.
More fridge freezers now come with super-cool and fast-freeze settings.
Although you shouldn't use these settings too much if you want to keep your energy bills in check, we recommend using them whenever your unpacking food from a big shop. This is when your fridge and freezer will have to work hardest to cool back down, so it makes sense to use these settings to give them a helping hand.
Smart fridge freezers don't come cheap and certainly aren't a necessity, but there are a couple of ways they could help keep your food fresher.
For example, a few of the smart models we've tested have internal cameras, which send images of what's inside your fridge to your smartphone. While this won't keep your existing food any fresher, it does mean you're less likely to buy fresh fruit and veg that goes off before you eat it because you didn't realise you already had some to eat up at home.
When you get the food home, for instance, you can use the tablet on the fridge door to attach labels to your items and it will then keep tabs on how long your food has been in there, reminding you to eat it while it's still fresh or because it's about to go out of date.