The good news about onions is that, unlike most other vegetables, onions keep for a really long time, without even losing quality.
Onions store best in a cool, dry, dark place. They tend to keep the longest on the door of the fridge.
That’s the quick answer; but read on for a few more details, which will give you the best shelf-life from onions.
Start with Good-Quality Onions
Start by choosing only onions that are in good condition. The U Mass Amherst Extension stresses the importance of this:
Damaged bulbs give off moisture, which is favorable for development of diseases in storage.”
University of Massachusetts at Amherst Cooperative Extension
…so, you don’t want to spoil all of your onions because you happened to overlook one bad one. A good onion feels firm. A soft spot indicates spoilage, or that it has been dropped. There must be no trace of mold on it. The best onion’s coppery skin will have a nice sheen to it. It also helps to buy no more onions than you will use in a couple of months.
Get the Most Out of Every Onion
You needn’t use a whole cup of onion or one whole onion in a recipe. If you find that much onion overwhelms your recipe, simply cut off as much of the onion as you wish to use, and seal the rest in a Ziploc sandwich bag. Alternatively, you could get a specially-made onion container (check price). Since it can be washed and reused, it’s more environmentally friendly.
Either way, be sure to have very clean hands with no lotion on them, if you’re going to use up an onion gradually – Transfer of bacteria from unwashed hands can cause your onion to spoil faster.
The Best Way to Store a Larger Quantity of Onions
On the other hand, if you use a lot of onions, the door of the fridge isn’t going to cut it. Other places in the kitchen are too warm, which will shorten the life of your onions. Well-built metal containers (view here) are properly vented and will facilitate easy and attractive garage or basement storage.
If you opt to store your onions in the garage, you may need an alternate location when Winter arrives, according to Richard Jauron, Extension Horticulturalist at Iowa State University, who says:
…since the temperature in an unheated garage may fall well below 32 degrees F, an alternate storage site will be needed when bitterly cold weather arrives.”
R. Jauron
Need an Even Simpler Onion Solution?
Some people only use onion as a little bit of seasoning; or may simply dislike working with them. For these folks, using a form of prepared onion may be a better solution. Of course, there are onion salt and onion powder (the only forms of onion my late father-in-law could stomach). Onion also comes chopped and frozen in the frozen vegetable section of your supermarket.
My favorite alternative form of onion is dehydrated minced onion. To make it more mild and with a better texture, soak it in water and microwave for a few seconds. Be careful – It can boil over very suddenly! Then, pour off the water, rinse, and use in your recipe.
