There are a few easy ways to check whether the onions in your kitchen are spoiled or fit for consumption.
First check for the appearance of the onion, if the onion peels have strange dark spots, the dark spots indicate that the onion has gone bad and may eventually start to rot.
After this, always check that the onion is not sprouting as it indicates that the onion has started to spoil. Sprouting is the beginning of onion spoilage.
Touch the onions, if they have become soft, mushy, then it’s time to discard them. Also, if there is a strange rotting smell coming from the onion, then throw it away.
Bad onions may develop dark spots, which will eventually begin to develop mold. You will also want to avoid onions that are beginning to sprout, as this indicates that they are starting to go bad.
You can also feel your onions to see how fresh they are. Onions with soft or pulpy spots are starting to go bad.