Onions are so much a part of our lives that it’s almost like a must have ingredient in the kitchen.
It is one of the most important vegetables grown and consumed globally, used as a flavoring and taste enhancer of a myriad of dishes.
However, when a white onion goes bad, it might smell strange, get discoloration in the skin, grow mold, or get soft and squishy.
In addition, they might dry up and grow sprouts.
Onions, like most other horticultural produce, are susceptible to post-harvest losses, the most significant of which are water losses, sprouting and rooting.
White onions have similar signs to other types of onions when they start to spoil.
The clear signs that white onion has gone bad are:
Discoloration – The formation of black or brown spots on the outer skin of an onion is the first sign that it is going bad.
You should peel or cut out any discolored spots in the inner layer of the onion and use it up as soon as possible.
Mold – Onions that have been exposed to moisture will develop mold on the surface.
Examine the onions carefully; if you only find the mold and no other signs of deterioration including dark spots, a weird smell, or squishiness, you can extend the shelf life of the onions by cleaning off the mold with a cloth and storing it in the refrigerator until ready to use.
It is best to use molding onions as soon as possible because they will collect moisture in the fridge and begin to decay.
Odd smell – A rotten or spoiled onion has a distinct odor, similar to that of rotting compost.
Soft or squishy – Onions that have soft or mushy patches are beginning to spoil.
The outer skins of your onions should always be crisp and dry, and the flesh should feel firm when pressed.
The flesh should be moist and not dry.
Drying and Sprouting – Sprouting onions means the onion simply evolved to the next stage of its life as a result of factors such as age and temperature.
While still safe to eat, sprouted onions may taste bitter.
Soon after sprouting, the onion may become squishy and shrivel up.
Time to chuck it!
How to tell if cut onion is bad?
When an onion is cut, it starts to oxidize and might start to turn brown.
In addition, the greater exposed surface area encourages the growth of bacteria and other microorganisms.
Cut onions release nutrients and expedite the growth of microorganisms.
Freshly-cut onions could also turn slimy.
The cut surface raises the moisture content, increasing water activity and encouraging the growth of bacteria and other microorganisms.
If you notice any bad smells or mold begins to grow, it should be discarded.
It is a common myth that cut onions cannot be kept and will absorb bacteria.
However, the “juice” in an onion is antimicrobial, meaning it will repel bacteria rather than absorb it.
According to the National Onion Association, cut onions can be refrigerated for 7 days at 32 °F. (Source)
There are various types of onions, and each type of onion has a different taste and is used in different types of dishes.
Not all types of onions can be eaten both raw and cooked due to their strong flavor.
White onions are a type of onion that tastes great both raw and cooked.
With a milder, less overpowering flavor, they are a favorite ingredient in Mexican cuisine.
White onions have a thicker, more papery skin than yellow onions.
They are milder, slightly sweeter, and frequently used in salads, salsas, and soups.
How long does a white onion last?
Whole white onions can last for four to eight weeks in a cool, dry, dark area.
If peeled, sliced, or cut, they can be stored in the refrigerator for up to seven days.
How long white onions last will depend on how they are stored.
Whole white onions should be stored in a dark, dry place with good ventilation.
A pantry, basement, cellar or garage with a temperature of 45-55°F would be ideal places to store onions.
They require ventilation and should not be stored in airtight containers or plastic bags.
A vital condition to storing onions well is to keep them dry.
Avoid keeping them in fridges as they spoil faster in a damp environment.
Keep them away from heat sources like stoves and bright, sunny areas near windows.
Peeled or cut onions have to be eaten within a week.
Store in the refrigerator in an airtight container or freezer bag.
Store cut onions away from other fruit and vegetables, as onions give off a scent that could be absorbed by other produce.
While chopped onions have more surface area that could attract bacteria, the nutrient content, and juice of an onion is naturally antimicrobial and can repel bacteria.
Cut onions can be stored in the fridge
To store cooked onions, place them in an airtight container and refrigerate them within two hours of cooking.
While it is perfectly safe to store cooked onions, note that fried onions don’t keep as well because their crispness fades and any seasoning often lessens.
Cooked onions, whether sautéed, roasted, or grilled, can be stored in an airtight container in the refrigerator for three to five days.
Onions are an indispensable, versatile ingredient found in almost every kitchen.
They are affordably priced and available year-round.
Knowing how to store your onions minimizes food waste and ensures fresh, nutritious onions that you can include in all your cooking!
Where should onions and potatoes be stored?
Onions can be stored in a cool, dry place for up to two months, similar to potatoes.
However, avoid storing potatoes and onions together because the ethylene gas that onions emit can accelerate ripening and sprouting in potatoes, speeding up their deterioration.
The ideal storage temperature is 45-55°F.
Ensure adequate ventilation and avoid storing them in airtight containers or bags.
Do not store whole, uncut onions in the refrigerator.
The cold, humid temperatures convert starch to sugars, making the onions mushy more rapidly.
Mold and sprouting are caused by moisture and light, so store your storage onions in a dry, well-ventilated basket, bin, or large bowl.
The mesh bag that onions often come in makes excellent storage bags.
Keep them out of direct sunlight and in a cool environment with some air circulation.
Potatoes should be stored in cool, dark places with an ideal temperature between 45 and 50° F.
Never store potatoes in the refrigerator; the colder temperatures will convert the starch in the potato into sugar, affecting the way they taste and cook.
It is best to store potatoes in dark places because light exposure can cause the skin of the potatoes to turn green.
Potatoes exposed to light will produce chlorophyll, encouraging the production of a compound called solanine.
Do not eat green potatoes, they contain a potentially toxic compound called solanine.
Solanine can damage cell membranes and affect the intestines.
Symptoms of solanine poisoning can be severe and include:
– breathing difficulties
If you suspect you or another of solanine poisoning, go immediately to the ER. If left untreated, toxicity can worsen.
I’m Chris Watson & the Founder of EatForLonger.com. I’m a food and wellbeing enthusiast researching and sharing foodstuffs and simple food-based concepts, such as fasting and clean eating.
I hope it inspires you to make tiny changes to what you eat and when you eat while optimizing your healthspan and all-around well-being.
Read more About Me here.