Don't wash your onions or garlic before you store them. Keep them very dry. While in Storage Check and cull them often to make sure the onions and garlic are not sprouting or developing soft spots. Remove and eat any damaged bulbs.
Do not clean them by washing them in water in an effort to get them squeaky clean. The lingering presence of moisture can lead to rot later on, so you want your bulbs to be as dry as possible. It's better to have a bit of dirt on a healthy bulb (after all, you'll be peeling them before you serve, them, right?)
Brush off excess dirt from the onion bulbs and roots with your fingers. When the leaves are dry down to the bulbs, wipe pruning shear blades with rubbing alcohol, and trim the leaves to 1 inch above the bulbs, unless you intend to braid the leaves. In hot, dry weather drying normally takes about four days.
Onions should be stored at room temperature, away from bright light, and in a well ventilated area. Onions are packaged in mesh bags because they like to breath. Avoid keeping them in plastic bags.
You want to minimize moisture and oxidation, both of which will affect the flavor and texture of the cut onion. So if you're prepping for a big feast, pre-chop your onions and store them in the fridge in an airtight container.
It is absolutely important that you rinse fruits and vegetables before consuming them raw, even if you are going to peel them!
After harvesting, dry or cure the onions in a warm, dry, well-ventilated location, such as a shed or garage. Spread out the onions in a single layer on a clean, dry surface. Cure the onions for two to three weeks until the onion tops and necks are thoroughly dry and the outer bulb scales begin to rustle.
Place the container in a dry, dark spot, like in the back of your pantry or inside a cabinet. Sunlight can affect temperature and humidity, causing onions to go bad. Properly stored whole onions will stay fresh for 6 to 8 weeks.
Plastic milk and storage crates are great for curing onions. You can turn them upside down and put the onions on top to further increase air circulation. If you don't have something elevated to place them on, you can also lay them out on newspaper or even hang them in small bunches to cure.
What you don't want is to have your potatoes and onions in close proximity, as gases from the onions can hasten sprouting in potatoes. Kept in the dark: Davison says your potatoes should be stored inside a paper bag in a cool, dark, dry place. And as mentioned above, away from onions and their sprout-encouraging gases.
THE BOTTOM LINE: Store leftover halved onions wrapped tightly in plastic wrap or in a zipper-lock bag or airtight container in the fridge for up to two weeks. Alternatively, chop them and freeze them for up to six months. Be sure to use the stored onions only in cooked applications.
Onions cure best in a shaded, dry, and cool place. This can be in a shed or on a covered porch away from direct sunlight. Spread the onions out or hang them so air can circulate around the bulbs and dry evenly.
Selecting the right spot to cure your onions is really important in your onion drying process. You don't want it to be in direct sunlight, even though we want them to dry. If they're in direct sunlight, then you run the risk of actually sunburning your onion.
To dry onions in the oven, spread them in a thin layer on a baking pan covered with parchment paper. Bake at 140°F until they are completely crunchy dry. It is suggested to stir and re-spread the onion bits every 30 minutes as you go.
Keep storage onions in a cool, dark, and dry place. Moisture and light lead to mold (ew) and sprouting (annoying, though not a deal-breaker), so stow your storage onions (red, yellow, and white as well as shallots and the diminutive pearl and cippoline) in a dry, well-ventilated basket, bin, or large bowl.
The outer skins of onion and garlic provide an excellent source of vitamins A, C, E, and numerous antioxidants. The skins of onions are also a rich source of flavonoids, particularly quercetin, a potent antioxidant and anti-inflammatory.
Keep Onions Away From Apples and Potatoes
"Probably the best example of this is storing onions with apples—you will end up with onion-scented apples! —and more commonly, onions with potatoes.
For maximum freshness, onions should be peeled before refrigeration. If stored whole and unpeeled in the fridge, they will spoil within 7-10 days due to moisture absorption which can cause them to become mushy. It is best practice to store diced or sliced onions for up to two weeks for optimal flavor preservation.
POTATOES
Store them in a paper bag - more breathable than plastic - in a coolish spot, such as a pantry. Keep them away from onions or fruits like apples that exude ethylene gas, which can make your spuds begin to sprout.
Veggies like potatoes and onions stay freshest in a cool, dark place, so keep them stored in the cabinet. Stock up on glass and plastic containers for your dry ingredients.
Saving Your Onions
First, let's take a look at how long an onion will last in your refrigerator's vegetable drawer. Generally speaking, onions should last between seven and ten days in your refrigerator and six to eight months in your freezer, but all of that can depend on how they are stored.