How to Tell If an Onion Is Bad

Unmistakeable Signs and How to Read Them

Written by Elisa Chan. Updated on How to tell if the onion is bad

Shelf-Life Of an Onion.

Onion is one of the most popular vegetables in any kitchen. It can be added in various dishes, raw or cooked, and some people even use onion circles for their sandwiches. Fresh, fried, boiled or dry – onion has endless options for culinary experiments.

How to tell if the onion is bad? You should check for dark spots and sprouting of the onions. Dark spots mean that the mold starts to grow, take the onion and try to squeeze it, the fresh onion will be heavy and firm. If it is soft and mushy, it is gone bad.

In this article, you will know everything you need about this vegetable!

How Long Do Onions Last?

The good news is that onion is one of the most long-lasting vegetables that can be found in our fridges! How long does onion last in the fridge? Of course, everything depends on the state of the vegetable and the conditions it is being stored at. To clarify this issue, let’s check out the following information.

  • Raw and whole onions can be stored for two or three months if they are kept in a cool dark place with the temperature around 45-55 degrees Fahrenheit. If you don’t have a thermometer to measure the temperature, just remember that it must be warmer than in the fridge and cooler than the average room temperature.
  • Life of a properly stored whole and raw onion in a fridge can last up to three months.
  • How long do cut onions last? Chopped or sliced raw onion will survive for a maximum of ten days in the fridge only if being kept in an airtight container. Nevertheless, if you have cut your onion in two pieces, it is better to put them into a plastic bag, airtight container or simply wrap in a plastic cover.
  • The shelf life of cooked onions depends on where you keep them. If they “live” in the fridge, then they can be used up to five days approximately after you cooked them. If cooked onions dwell in your freezer, they will remain eatable for up to one year.

Ans how long do onions last? Fresh onions last up to 2 months if refrigerated. Cooked onions will last from 3 to 5 days in the fridge and up to 3 months in the freezer. Freshly chopped onions last for 1 week in the fridge. For long-term storage, freeze them in a resealable bag or airtight container.

How to extend the onion shelf-life

How Long Do Onions Last
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Do onions go bad? Of course, they do, especially when being stored improperly! To make onions available for cooking even longer, follow several easy but very useful tips that will allow you to enjoy this vegetable while you are storing it at home.

  • Onions like cool and dark places, for example, in the cellar. If you don’t have one in your house or apartment, simply put onions to the fridge.
  • To help your onions last longer, wrap them in loose paper or keep onions in a mesh bag or basket. It will allow the air circulate properly and the vegetables won’t get rotten fast.
  • Never keep onions in p[lastic bags as they lack air inside which ruins the vegetable.
  • It’s better to prevent the onion from “living” close to potatoes because then both of them will get spoiled faster.
  • Never keep your onions close to the fresh fruits, even watermelons. The reason is simple: fruits produce a specific gas that speeds up the process of spoiling and rotting of the vegetables. 

And how to how to extend the onion shelf-life? To extend the shelf life of onions, keep them whole.  Place them in a well-ventilated, cool, dark place, such as a pantry up to 40 – 50 °F. When exposed to excessive moisture and light, the onions will sprout and rot. Properly stored onions will last up to 3 months.

How to extend the onion shelf life

How long can onions last in the freezer?

How Long Do Onions Last
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Freezing onions is a good method for preventing them from spoiling. 

To do this, simply peel onions, then slice or chop them depending on where and how you are going to use them later. 

Did you defrost the onion?
Yes, once
Many times
Great that you recalled. I just have onions in the freezer.
No, I didn’t have to

Put onion circles into an airtight container or a special bag for freezing. One more option to use is to wrap onion tightly with aluminum foil.

And just send it to the freezer!

How to defrost onion?

shelf life of cooked onions
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Frozen onions can be easily defrosted. Depending on how soon you will need to use the onion, you can leave it on the table or the kitchen counter to defrost, otherwise, a microwave can be used to speed up the process. 

No matter what method you choose, the procedure won’t take you more than a couple of minutes.

There is only one thing to keep in mind regarding frozen onions: they will never be the same. As onions contain pretty much water inside them, freezing and defrosting cause this water to expand first and then condensate. It means that, after you defrost the previously frozen onions, they will be somewhat soft. 

For this very reason, it won’t be possible to use defrosted onion in salads or as a topping for any dish

And how to defrost onion? To defrost homemade frozen onions, put them in a plastic bag, then place the bag into the cold water for 15 minutes and wait for about 30 minutes.  If your onions are very thin, simply start to use them, and it will thaw in one minute.

How to defrost onion

How to Tell If an Onion Is Bad? 

How to Tell If an Onion Is Bad
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What if it so happened that you suspect your onions got rotten? Well, to begin with, it is quite easy to identify bad onion in your fridge as onions become soft and darken or even lose their color in this case. Also, the specific smell will give the rotten onions out.

If you are still not sure whether the onion is not good, check it for any of these signs of spoiling.

  • Loss of color
  • Bad smell
  • Mold
  • Soft and squashy surface
  • Sprouts
  • Dry flesh
  • Soft areas on the surface
  • Dark dots

This list can be applied not only to the ordinary onion but also to the leek, green onion, and scallions.  

When do onions go bad? Apparently, if they are being stored under improper conditions such as too high or too low temperature, excess of light, lack of air, storage with potatoes (which speeds up the spoiling process of both vegetables, by the way) and other reasons. 

How to tell if green onions are bad you may ask? The same way as you would use for leek and other onions of that kind. If you see it’s soft and somewhat slimy, notice its color changes (it’s faded or became pale-yellow), if the onion feathers got dry then it is better to throw it away and buy a new one.

How to Store Onions for 6 MonthsHow to Store Onions for 6 Months

As you can see, even though onion is not that complicated to deal with, some specific rules still need to be followed if you want to keep this vegetable eatable and durable to enrich your dishes with its flavor and taste! Keep them in mind and you will never have to throw away any single piece of onion.

How to Tell If an Onion Is Bad

FAQ And Everything You Ever Wanted to Know

Onion is a widespread vegetable in any kitchen all over the world and an irreplaceable ingredient in many dishes. No wonder we buy onions in big bags and toss them to the fridge…to find them rotten pretty soon!

Have you ever wondered how to tell if the onion is already bad? Do different sorts of onion get spoiled in different ways?

Below you will find the answers to these and other questions!

How to tell if a red onion is bad?

If you see the dark spots, sprouts, or weird sweet smell that means that the red onion becomes bad. If you noticed the slimy texture or black mushy spots that means that the onion has mold inside. And you should throw it out.

To find it out, take it and take a look at it attentively. Fresh red onion is heavy and quite hard to the touch. They have a neutral scent with a very light trace of typical onion odor with some sweetness.

How to tell if a red onion is bad
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Unlike the fresh vegetable, spoiled one may be soft, partly or whole, with some dark-red or brownish spots on the skin and with an unpleasant acidic odor. If there is any mold or moist areas on it, discard the onion instantly.

How to tell if a cut onion gone bad?

If you feel sweat or smell it means that cut onions are already gone bad. If it has a slimy texture or become soft and had already changed its color to yellow or black you should throw it out.

You need to meticulously examine your onions. If they are soft or have a slimy texture if they smell weird and obviously bad, then they are already passed away.

So how to tell if a cut onion gone bad? The cut onion is bad when it has an unpleasant smell, taste or mold starts to grow. If cut onion has black spots on it, don’t use it. Store homemade cut onions in the refrigerator on the lowest shelf for 7 days at 32 °F. Store unopened store-bought cut onions in the fridge for 10-12 days at 36°F

How to tell if a yellow onion is bad?

How to tell if a yellow onion is bad
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To spot a rotten or spoiled yellow onion, take a look at it. If it has any strange color changes (like dark spots or discoloration), if it is soft to the touch or you find any slimy areas and of course, if there is mold and the smell is awful, then simply discard it.

How to tell if a brown onion is bad?

Spoiled brown onion may be a bit more difficult to spot compared to the yellow one because if its external husk. Nevertheless, the second you notice any dark spots on the husk or the husk become soft to touch and a bad smell appears, it means that the onion must be thrown away to the garbage.

How to tell if the chopped onion is bad?

With a chopped onion it may be a bit more tricky. Anyway, the best way to tell that it has turned bad is to smell it. If the odor is stinky and acidic and if the onion is slimy, then you need to discard it.

How to tell if the diced onion is bad?

How to tell if the diced onion is bad

The same way as you would do with the chopped onion, smell it first. Any weird odor, as well as the slimy traces, will tell you that the vegetable is unconsumable anymore.

And how to tell if the diced onion is bad? Diced onions can be stored in a plastic bag or container in the refrigerator on the lowest shelf for up to 7 days at 32 °F. If you see mucus, mold, dark spots, or it changed its natural shape, your diced onions are bad. Strange smell or you see sprouts on the diced onions throw them out.

How to tell if french onion dip is bad?

The best and the fastest way to figure that out is to look inside the container. Except for the off odor and flavor, mold is also a sign that something has gone bad. Are there any other ways how to know if french onion dip is bad? Unfortunately, there aren’t.

So how to tell if french onion dip is bad? French onion dip is bad when it has an unpleasant smell or mold on it. Always store open homemade french onion dip in a container in the refrigerator at 32 °F.  Keep unopened store-bought sauce in a cool dark place. Closed sauces can be stored at room temperature 68 °F

How to tell if Vidalia onion is bad?

How to tell if Vidalia onion is bad

Vidalia onion is the same onion as other kinds of this vegetable and it gets spoiled the same way. Any traces of mold or soft and slimy texture in addition to the off smell and color changes will tell you that the onions must be thrown away.

And how to tell if Vidalia onion is bad? If you see mold, dark spots, or sprouts on your Vidalia onion that means that the onion is spoiled. Store onions in a cool, dry place at 32 °F and keep the onions separated. Store your Vidalias in the refrigerator, wrapping each in a paper towel.

Written by
Elisa is a passionate cook who will advise you on healthy and delicious food topics! With her help, you will discover how to properly store and freeze food, as well as learn important nuances about preserving vitamins in your meals to make them stay nutritious.
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