Onions are an incredibly important food all around the world and many of the world’s traditional dishes would not be the same without onions. Onions are also very easy to keep fresh. However, just like other foods, they can spoil if not stored properly.
When stored correctly, onions can last anywhere from 2 months to 8 months depending on how and where you store them. The signs that an onion has gone bad include a bad smell, discoloration, and mold growth.
To keep your onions fresh as long as possible, it is important to understand the best methods for storing onions and how long they keep using each method.
How Long Does an Onion Typically Last?
The length of time that an onion will typically last depends on how and where you store it as well as if the onion has been cut or not. How long do yellow onions last will have a different answer than how long onions last in the pantry, especially if the yellow onions are being stored in the refrigerator.
Whole
No matter how they are stored, whole onions typically last must longer than chopped onions. This is because they still have their protective layers of skin that help to protect the food from bacteria and other damage.
The skin also helps to protect the onion from oxidation, one of the main factors in spoilage. Once the onion is cut, all of the layers that were previously protected are exposed to oxygen which speeds up the spoiling process. It also allows bacteria to enter the onion more easily.
Pantry
When onions are stored in a cool, dry pantry, they can last for several weeks. The colder the pantry is, the longer they can last. If the pantry is between 40 and 50 degrees Fahrenheit, the onions can stay fresh in their whole form for up to one year.
The most important factor in pantry storage is keeping the onions in a cool area away from direct sunlight. You should also avoid moisture as that will rapidly increase the rate of spoilage.
Fridge
Storing your onions in the fridge will prolong their life even more. It will majorly slow down the spoilage process which helps your onions to stay fresh as long as possible. In the refrigerator, onions will last a minimum of 2-3 months.
The main factor to consider is the moisture level in the fridge. If the moisture level is high, this could speed up the spoiling process even if the temperature is kept low. High moisture levels could also encourage the onions to sprout which will quickly ruin them.
Freezer
As is the case with most foods, onions will keep the absolute longest when stored in the freezer. Raw, whole onions will stay fresh in the freezer for up to eight months before they should be thrown away.
However, it is not recommended to freeze onions in their raw form. They can be difficult to thaw and it can be easier if you chop them up before adding them to the freezer. This will allow them to freeze more quickly and make them easier to thaw.
Chopped
Generally speaking, chopped onions have a far shorter shelf life than whole onions. When onions are cut, they lose the protection that their skin provided. Bacteria can enter the onion more easily which will speed up the spoilage process.
Removing the skin and chopping up the onion also increases the amount of the onion that is exposed to the air. This dehydrates the onion and can also speed up the spoilage process.
Pantry
Cut onions will only last 1-2 days at room temperature. Since they no longer have their protective skin, they will spoil far more quickly than whole onions.
Ideally, you should not store cut onions at room temperature, even if it’s in a cool, dry pantry.
Fridge
In the refrigerator, cut onions will last for about 1 week. This is the best way to store cut onions if you plan on using them up fairly quickly.
Just make sure to store them in an airtight container. This will prevent the smell from contaminating the other foods and keep the onions from drying out too much.
Freezer
Just like with whole onions, cut onions can last up to eight months in the freezer before they should be thrown away.
Cutting onions before freezing them is the easiest method for freezing. This allows you to portion the onion out into small servings so you don’t have to thaw an entire onion every time you need a couple of spoonfuls for a recipe. It also speeds up the freezing time and makes for an easier cutting process at the end.
Just like with refrigeration, make sure to store your chopped onions in an airtight container, preferably a freezer bag, before freezing. This will help prevent freezer burn and keep the onions from drying.
How Do You Properly Store Onions?
The best way to store onions is in a cool, dry area like a pantry. That is unless you are trying to preserve the onions for more than their usual shelf life of around two months.
If you are planning on keeping your onions for more than three months maximum you should store them in either the fridge or freezer.
Fridge
If you are storing a whole onion in the fridge all you have to do is place it in the produce drawer. The produce drawer is typically drier than the rest of the refrigerator. This will help to prevent the onion from spoiling. Since the onion still has the skin, the smell of the onion should not soak into the rest of the food in the fridge.
When you store a chopped onion in the refrigerator all you’ll need to do is place the chopped onion in an airtight container. This will keep the onions from drying out and keep the smell contained. The last thing you want is to pull an apple out of the refrigerator and have it smell like onions.
Freezer
When you freeze a whole onion you will simply want to place several whole onions in a freezer bag and then squeeze out as much air as possible. This will help to prevent freezer burn and dehydration. After that, you’re good to go and can put your whole onions in the freezer where they should stay fresh for up to eight months.
When freezing chopped onions the process is pretty much identical. Simply portion the chopped onions out into freezer bags, squeeze out all the air, then toss it in the freezer where it will keep for up to eight months.
How to Tell If Onions Have Gone Bad?
Since onions last so long, it can leave some people worrying about whether their onion has already gone bad. Especially if they can’t remember exactly how old the onion is. Fortunately, there are several easy signs that you can look at to determine if your onion has gone bad or not.
Smell
The first sign that you’ll likely notice if your onion has gone bad is a change in the scent. Onions normally have a strong smell, but if they begin to smell especially pungent or develop a rancid odor, that’s a sure sign that your onion has gone bad.
Color
The color is another easy way to tell if your onion is still good. Good onions will have an even white, light yellow, or purple color depending on the type of onion that you purchased. If the onion begins to develop dark, uneven patches then it has likely spoiled and should be thrown away.
If you see small black specks on the outer layers of your onion skin it is not a sign that your onion has spoiled. It is most likely a type of mold that is completely harmless to humans and can be easily removed by peeling away a few layers of skin.
Mold
Although a small amount of black mold on the outer layers of the onion’s skin is normal, fluffy mold that grows directly on the onion is not. If your chopped or whole onion begins to grow a significant amount of mold you throw it away immediately.
Related Questions
Can you freeze onions?
Yes, you can freeze onions and they will keep for up to eight months in the freezer. Just make sure to store them in an airtight container to prevent freezer burn and keep them from drying out.
How many months should onions only be stored?
Onions can be stored for many months if stored properly. They can keep for 2-3 months in the pantry on average and a few months more in the fridge. The freezer will keep them fresh the longest at up to eight months.
Why are my onions rotting in storage?
The most common reason that onions rot in storage is because of high moisture levels. High moisture levels will rapidly cause the onions to soften which can lead to rot.
Conclusion
Onions are an extremely important ingredient in many dishes around the world. They are also known for their ease of storage and the length of time that they stay fresh.
In the pantry, onions can last for 2-3 months, much longer than most other vegetables that will rot within a few days of being kept at room temperature. In the refrigerator, they can keep for several weeks longer. Finally, they keep the longest in the freezer where they can stay fresh and flavorful for up to eight months.
If your onion develops a rancid smell, discoloration, or begins to grow mold, these are all signs that your onion has gone bad. If you notice any of them you should throw the onion away immediately.
