How To Properly Store Half an Onion?

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Everyone who’s cooked for long enough has dealt with leftover ingredients at one point.

In this article I’ll teach you how to store half an onion without its smell penetrating the other foods in your fridge or its cut side rotting.

Fortunately, you can store an onion after cutting and prevent it from turning your fridge into a fallout zone.

Let me explain how you can do that so you can focus your attention on more important manners.

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How to properly store half an onion?

Storing an onion that’s already been cut can be a bit perplexing at first.

After all, whole onions are kept at room temperature so it’s natural to think you can do the same with ones that are cut.

Well, that’s unless you take into account the fact that cut onions don’t have their protective layer and get exposed to all manner of bacteria and mold.

So what’s the proper way to store half an onion then?

The best way to store half an onion is to wrap it in plastic and place it in the fridge with the cut side facing down. This will prevent any odors from escaping and slow down microbial growth.

half an onion with the cut side facing down and wrapped in plastic wram and a paper towel

by trufflelover1

You can also preserve cut onions in a ziploc bag or a resealable container.

However, I don’t recommend the latter since the onion smell will linger long after the onion is gone.

Whichever method you choose, you should always make sure that the onion is tightly sealed or wrapped.

Otherwise, it might spoil or release a strong odor that can soak into other food items in your fridge.

It’s also worth noting that it’s better to leave the outer skin on since it decreases the chance of contamination.

If you don’t cook very often or aren’t sure when you’re going to need onions again, you can also freeze leftover onions.

However, you’ll need to chop them first since larger pieces such as halves are at a greater risk of freezer burn.

Once you’ve chopped the onions, you should place them in a resealable bag or a freezer safe container and spread them as thinly as possible.

a hand holding a platic bag with chopped onions ready to be stored in the fridge

by dahliachuu

Don’t forget to label each container with the date before you throw it in the freezer. This will help you determine whether the onions are still good when you decide to use them.

Stored this way, leftover onion can last for up to 8 months before it spoils.

Keep in mind that the texture of onions changes when they get frozen. Due to this, it’s best to use them for stews, sauces or other dishes that rely on their soft texture.

Fortunately, this also means that there’s no need to defrost them and you can add them straight in during cooking.

In any case, you shouldn’t store cut onions without refrigeration as this promotes bacterial contamination and mold growth.

How long is a cut onion good for?

With proper storage, a cut onion can last between 7 and 10 days. However, its quality will slowly start to degrade after the 7th day.

Even though it will still be edible, you may notice a stronger and more bitter taste than usual.

If you aren’t sure whether your onions are still good, you can check their color, smell and texture.

If you notice any gray, brown or black spots, it’s best to assume they’re spoiled and discard them.

a hand holding an old onion that has some mold forming on it

by AUserNameThatsTaken1

Another tell-tale sign of spoilage is the appearance of slime. In case there’s any slime covering the onions you should throw them away.

Lastly, any unusual or off putting smells should also be considered as a sign of spoilage.

How to preserve whole onions so they don’t spoil?

Even though onions last significantly longer when they’re whole, they’re not everlasting.

If you store whole onions properly, they’ll have a shelf life of about 4 weeks.

This timeframe, however, will drastically shorten if the onions are stored in an environment with a high temperature and humidity.

This is because these conditions create a suitable environment for mold growth and bacterial contamination.

Therefore, the best way to store whole onions is to put them in a cool, dry place such as a garage, pantry or basement.

The optimum storage temperature you should aim for when keeping whole onions should be between 40-50°F.

You could also keep them at room temperature, but this will slightly decrease their shelf life.

Even though this may seem counterintuitive, it’s best to avoid storing whole onions in the refrigerator.

When kept in the fridge, whole onions tend to become soft and soggy due to the excess moisture.

They also spoil faster since the low temperature and high humidity speed up the breakdown of complex sugars.

And the conversion of complex sugars into simpler molecules attracts fungi and accelerates mold growth.

My short recap

If you cook for yourself or just aren’t that fond of onions, you’re bound to end up with leftovers.

Fortunately, you can store leftover onions in an airtight bag and keep them in your fridge for 7-10 days.

This way you’ll minimize food waste without smelling up your entire refrigerator.

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