Knowing how to store foods correctly may seem simple, but if you're not careful, you could end up with clumpy sugar, prematurely mouldy fruit and mayonnaise that's in danger of separating. So, to help you save money, cut down on waste and, most importantly, ensure your ingredients stay fresh and tasty for as long as possible, we've compiled a list of foods most people tend to store wrong – with advice on what to do instead.

Click or scroll through our gallery to discover 33 foods you never realised you'd been storing incorrectly – counting down to the most common mistake of all.

We've based our ranking on how common each mistake is, taking into account expert advice, research and the experience of our team. This list is unavoidably subjective.

It can be tempting to leave flour in a kitchen cupboard in the packet it was bought in – after all, it never really goes off, right? Wrong! Flour can start to go bad when exposed to sunlight, oxygen or moisture, so it's a good idea to keep it stored in an airtight glass or plastic container in a cool, dry place. Wholegrain flour, on the other hand, spoils more quickly because of the oil contained in the wheat germ; as such, your best bet is to store this kind of flour in the fridge or freezer.

Find yourself having to mix the oil back into the peanuts every time you open your jar of peanut butter? It could be that you've been storing it the wrong way up, allowing it to dry out faster. Instead, always store your peanut butter upside down – that way, when you flip it over to use it, the oil will naturally mix back through the jar, extending the life of the spread. Not only that, but you'll also score a sweet spoonful straight from the thickest part of the peanut butter, guaranteeing a supremely tasty snack.

Hands up if you’ve been storing your sandwich pickles in the fridge? Turns out you’ve been using up precious refrigerator space unnecessarily. Thanks to the preservatives used in shop-bought pickles, you can keep these vinegary ingredients in the cupboard instead – just make sure the lid is airtight and that you don’t contaminate the brine with a dirty spoon. If you’ve made homemade pickles or bought a fermented style, though, you’ll want to keep them in the fridge.

It may seem like a sensible idea to keep bread in the fridge; after all, it'll help to prolong your loaf's life. However, those extra mould-free days will come at a cost – refrigerated bread dries out quickly, becoming tough and chewy. To keep your loaves in tip-top shape, store them in a bread bin. Alternatively, for a long-term storage solution, you can also keep bread in the freezer (just be sure to wrap it up in two layers, like a bag inside a bag, first). You could even freeze slices, ready for the toaster.

Fed up with having to faff about scooping out the final few baked beans from the bottom of the tin with a spoon? Turns out we’ve been storing this cupboard staple incorrectly, too. Instead of resorting to vigorously shaking the tin to get the remaining beans out, simply store it upside down. This handy hack will stop the saucy beans from settling at the bottom of the tin. 

It's all too easy to put hard cheese straight into the fridge still in its plastic wrapping. However, doing so is a recipe for disaster – once you open the wrap, the surface of the cheese will be exposed to the cold air, leaving it dry and stiff. Instead, show your cheese a little love by wrapping it in a breathable material like wax paper or baking paper, sealing it up in an airtight container, then refrigerating. The texture and taste will be perfectly preserved.

While it may be tempting to pop garlic in the fridge along with the rest of the vegetables, storing the flavour-packed ingredient in cooler temperatures should be avoided unless it’s already peeled and prepared. Keep these handy bulbs at room temperature in a dry environment with good air flow – and always store away from direct sunlight.

Rice is another everyday ingredient that many people don't realise they've been storing incorrectly. If kept in its original box or packet, it can accumulate moisture and mould, causing it to become inedible. To keep your rice fresh for longer, consider storing it in a mason jar or washed-out jam jar – both of which are airtight and perfectly transparent, so you can see what's inside at a glance. Don’t forget to label each jar so you can tell your Arborio from your basmati and be sure to make a note of the use-by date.

Because kimchi is fermented naturally, most people assume it can be left out at room temperature with no problems. However, if you want to keep it at its best, the fridge is your friend. As soon as you buy (or make) your kimchi, put it in the fridge – the cold temperature will slow down the fermentation process, so it'll stay deliciously tangy for longer. To prevent any odours from tainting the other items in your fridge, be sure to keep it in an airtight glass or plastic container.

Been keeping your brown sugar in the bag it came in? You could unwittingly be contributing to it becoming clumpy and hard (a process that takes place as the moisture in the sugar evaporates). Instead, transfer it to an airtight container along with a moisture absorber like a terracotta sugar saver or a slice of bread. That way, it'll stay clump-free for up to six months. Similarly, white sugar should also be stored in an airtight container – this time to prevent any moisture from getting in, rather than out.

Cucumbers have a high water content, making them wonderfully refreshing but also prone to going limp and squidgy. If you've been leaving yours unwrapped in the fridge, it might be time to have a rethink; unwrapped cucumbers tend to spoil quickly, as the water inside them is able to evaporate easily. To store your cucumber correctly, wash and dry it, then wrap in a clean tea towel (or some kitchen roll) to keep condensation and humidity at bay. Be sure to stash your cucumbers in the warmest part of the fridge, too – that's towards the front, as far away from the harsh cooling elements as possible.

Lots of people store their maple syrup in a kitchen cupboard or pantry without a second thought – but did you know that this natural sweetener should be kept in the fridge? While it's true that honey never spoils, real maple syrup can go bad or grow mould if left out at room temperature. However, imitation maple syrup (or pancake syrup) contains preservatives, so it needn't go in the fridge. Be sure to check the label to find out where your go-to product belongs.

To refrigerate or not to refrigerate ketchup is perhaps one of the most contentious culinary questions. Many believe that because the tangy sauce boasts a high vinegar, sugar and salt content it can – and should – be kept at room temperature. But even condiment specialist Heinz recommends the opposite, stating: ‘this product, like any processed food, should be refrigerated after opening’ to extend its shelf life. If you’re the type of household who gets through a bottle every week, however, it’s fine to keep in the cupboard.

If you like your butter to be perfectly soft and spreadable, it may seem reasonable to leave it out in a butter dish on a kitchen worktop. However, like other fats, butter can spoil when stored at high temperatures – so, to keep it at its best for longer, be sure to keep it wrapped in its original packaging (or transfer to an airtight container) and stash it in the fridge. Wrapped up tight, it won't absorb the aromas of any pungent ingredients stored alongside it. You can also freeze any butter you're not planning on using straight away.

Have you ever really thought about which part of the fridge you're storing your mayonnaise in? Chances are, you haven't – but if you want your mayo to stay perfectly creamy and tangy for longer, it's worth considering. If you keep your mayonnaise at the back of the fridge, especially if your fridge is very cold, the consistency, texture and thickness of the condiment can change, causing it to separate. As such, the best place to keep it is in the fridge door, where conditions are slightly warmer.

If you find yourself with a surplus of fresh herbs, don't leave them to wilt in your fridge (or, even worse, resort to throwing them out). Here's a savvy way to store them – and lock in their flavour – for up to six months. First, rinse your herbs to remove any dirt, pat them dry, then chop them finely. Next, place a teaspoon or so of herbs into each compartment of an ice cube tray. Finally, cover with liquid before freezing; delicate herbs like basil, mint, chives and parsley freeze well in water, while hardier herbs like rosemary, thyme and oregano freeze perfectly in olive oil.

Think nuts and seeds belong in the kitchen cupboard or pantry? You're technically correct – but only if you're planning on eating them right away. Nuts contain a large amount of unsaturated oil, so they can oxidise quickly and go bad at room temperature. As such, if you have a large supply of nuts or seeds that you hope to keep for a few months, it's worth making space in your freezer. Stored in an airtight container, frozen nuts and seeds can last much longer than their store cupboard counterparts.

It may seem like a convenient idea if you're running low on space, but never be tempted to store raw meat on the top shelf of your fridge. Meat packages can leak, potentially contaminating other items stashed on the shelves below and, as a result, making you very sick. To stay on the safe side, be sure to get raw meat in the fridge as soon as possible after buying it and keep it on a plate on the lowest shelf.

Been leaving the leafy tops on your root vegetables? Strange as it may seem, this is another storage no-no. Root vegetables such as carrots, swedes and turnips will last longer if the green leafy tops are cut off before storing; this is because the roots draw moisture from the vegetables, causing them to dry out. Once the tops have been cut off, you can store the vegetables in the fridge to keep them nice and crisp – just don't wash them first, as any excess moisture can encourage rot and mould.

If you've been storing your homemade soups, stews, stocks and sauces in plastic containers in the freezer, you've been missing a trick. Instead, to save space (and to ensure that you don't have to throw anything away to make room for your batch-cooking creations), pour them into freezer bags and seal tightly. That way, you can lay them flat one on top of the other, or squeeze them in and around your other frozen foods with ease.

Forget about refrigerating salad leaves in the plastic packets you bought them in – the wrapping will only serve to seal in moisture, causing the contents to become limp. Here’s a simple way to keep your leaves fresh for significantly more time: wash them, spin the excess moisture off in a salad spinner, then pat the whole lot dry. Next, place the leaves on top of some kitchen roll, wrap them up, place them in a resealable plastic bag, then zip the bag shut, removing any air beforehand.

Coffee beans should be stored in a cool, dry place – but never be your fridge, even if you keep them in a sealed container. Coffee beans absorb odours, so while refrigerating them can keep your fridge smelling fresh, it'll make the beans themselves taste pretty odd. You shouldn't keep your beans in a jar on the kitchen worktop, either, as exposure to light will quickly degrade their flavour. If you don't plan to use all of your coffee beans in the near future, freeze them in a vacuum-sealed bag. Otherwise, store in an opaque, airtight container in a kitchen cupboard.

If you've been storing your potatoes in the fridge, this is your cue to change things up. When potatoes are refrigerated, the harmful chemical acrylamide can form, so it's best to keep them in a paper bag in a kitchen cupboard, pantry or other cool, dry place. They're perfectly fine to eat even if they start sprouting – just remove the eyes and sprouts before cooking. A word of warning, though: never stash potatoes and onions together. Onions produce ethylene gas, which can cause potatoes to spoil quickly.

Leaving a bundle of asparagus in a fridge drawer is a kitchen crime most of us will have committed at some point – however, it's a one-way ticket to dried-out spears and wasted woody stalks. To get the most from your asparagus, treat the spears like a bunch of flowers; keep the rubber band on to hold the spears together, trim off the ends, then put your asparagus in a jar or glass with a little water. Covered loosely with a plastic bag, the spears will keep in the fridge for up to a week.

Do you tend to stash your avocados in the fridge, regardless of how ripe they are? You could be doing them an injustice. Colder temperatures can prevent avocados from ripening fully, leaving you with fruit that's unappetisingly hard and pale. Instead, it's best to leave them to mature on a kitchen table or worktop. Once your avocados have reached maximum ripeness, you can then transfer them to the fridge for a few days. When storing avocado that's already been cut up, add a little lemon juice to prevent browning.

Another vegetable people tend to transfer to the fridge while still in its plastic wrapping is broccoli – but leaving it tightly wrapped, or even cramming it into the salad drawer along with lots of other vegetables, can speed up the process of ethylene gas breaking it down, causing it to go bad. Instead, take it out of its packaging, and allow plenty of room for it in your salad drawer. Be sure to eat broccoli quickly, too; the longer you leave it, the lower its nutritional content will be.

Bright and colourful citrus fruits may seem like the ultimate fruit bowl–filler, but really, a room-temperature kitchen table or worktop is the worst place for them. Unlike other fruits (bananas, for example), citrus fruits don't continue to ripen after they've been picked; in fact, they start to deteriorate straightaway, so you'll need to keep them cool to extend their lifespan. To ensure your oranges, lemons and limes stay fresh for up to four weeks, store them in the fridge in a resealable plastic bag.

Depending on where you live, you could be storing your eggs wrong if you're leaving them out of the fridge. In the USA and Canada, eggs are washed at processing plants, removing the natural membrane that helps to keep bacteria out; as such, they should be refrigerated to stay fresh for longer. Keep them in the main body of the fridge, rather than the door (where the temperature fluctuates). In Europe and other parts of the world, eggs are sold unwashed – with the membrane still intact – so they can be stored in a cupboard or pantry with no problems. 

It may be incredibly handy, but keeping your olive oil in a clear glass bottle next to the hob is another food storage sin many of us are guilty of committing. Unfortunately, oil oxidises when exposed to heat and sunlight, making it lose its flavour and causing it to spoil, which is not ideal, particularly when olive oil is so expensive. As such, next to the hob is the last place you should be storing it. To do right by your olive oil, keep it in a dark place, away from heat and sunlight. The same goes for dipping and drizzling oils, too.

Been storing your bananas in a fruit bowl, or leaving them out on a hanger on a kitchen worktop? You may have noticed that they ripen very quickly this way (it's all down to ethylene gas speeding up the maturing process). To help them last longer once they're ripe, your best bet is to store them in the fridge. The skin may turn brown or black if you do so, but the fruit inside will be as tasty as ever. Top tip: once inside the fridge, keep your bananas away from apples, avocados, peaches, pears, peppers and tomatoes, which also release ethylene gas.

Do you tend to stash onions in your fridge's salad drawer? Sadly, this really isn't the best place for them – without enough air circulation, they can go unpleasantly soggy. Instead, keep them in a mesh bag or transfer to a breathable container, then store them in a cool, dark place like a kitchen cupboard or pantry. As mentioned earlier, never store onions in the same place as potatoes; onions produce ethylene gas, causing potatoes to spoil, while potatoes release moisture, prompting onions to go mushy.

Most people store tomatoes in the fridge – but if you want them to stay fragrant and flavoursome, you're better off keeping them out of there. The taste and texture of tomatoes breaks down when they get too cold, so it’s best to store them at room temperature, but away from heat, light and moisture. It's also unwise to pile tomatoes on top of each other in a bowl; if one goes bad, it’ll quickly spoil the others (plus, the tomatoes at the bottom will get crushed). Instead, arrange your tomatoes on a plate, leaving a little room for air to circulate between them.

It may seem like the fridge door was just made for storing milk. But, every time you open that door, the items stashed there will be exposed to warmer conditions. If milk is one of those items, the fluctuating temperature will cause it to spoil more quickly. To ensure it stays fresh for longer, keep milk at the back of the top shelf, near the cooling vents; this is the coldest part of the fridge, so it's the ideal place to keep milk chilled.

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Last updated by Lottie Woodrow.