How to Store a Whole Onion
Whole onions don’t need to go in the refrigerator—in fact, it’s actually not a good place to store them. The fridge is a cold and humid environment, which can cause onions to soften and spoil. The best place to keep whole onions is somewhere dark, cool, dry, and well-ventilated. A perforated basket or bin in a kitchen cupboard checks all the boxes and would be an ideal location in which to store onions. When you’re at the grocery store picking out your onions, make sure to feel ’em before placing them in your cart. Avoid damaged onions with soft spots; they won’t be as fresh-tasting and won’t last as long. When you bring your onions home, don’t be tempted to save yourself a step later on and peel them, as the skin protects and preserves the inside. Following this advice, you’ll be surprised by how long whole onions stay fresh in your kitchen, ready for you to use at the drop of a hat.
How to Store Cut or Chopped Onion
You can store extra cut or chopped onion in an airtight container or plastic bag in your fridge, but make sure to use it within five to seven days. The longer onions sit in there, the stronger they smell, and you don’t want your fridge to reek of onions, infusing everything else in there. Another option is to follow the advice below and freeze your leftover onion, which will keep the scent at bay and preserve it for a longer period of time.
Can You Freeze an Onion?
We don’t recommend freezing whole onions because they’ll get very hard and won’t thaw well, but we absolutely endorse freezing chopped onions. In fact, any time a recipe calls for half of an onion, go ahead and chop the whole thing. Toss whatever you don’t use into an airtight plastic bag, making sure to squeeze out as much air as possible, then seal it and throw it in the freezer. Alternatively, if you buy a big bag of onions and know that you won’t use them all before they go bad, go ahead and chop a bunch of them just for your freezer! You’ll thank yourself the next time you make a soup or stew and have plenty of pre-chopped onions ready to go. We suggest dating your bags of onions for future reference, but they’ll stay good for upwards of six months, so it won’t be difficult to use them before they go bad.