I have a dedicated ‘onion’ jar: glass, with a metal lid so I don’t have to worry about it retaining odors OR allowing them to get out in the fridge. I believe that it originally held jumbo olives. Short and squat with a huge opening, it’ll take most onions.
When I have a left over giant purple olive I use one of the regular plastic storage containers then toss it afterwards. I get them all the time with lunchmeat in them, so no loss.
I use a newspaper to completely eliminate any onion smell getting into the fridge. I wrap the onion in plastic wrap, cover that in a piece of newspaper, and put it in a baggie. You won’t be able to smell it at all.
I dice the whole thing, toss the unused portion into a ziploc freezer bag and whenever I need some more onion, I pop open that bag, dispense some frozen onion. Done.
I started doing this when I realized I was spending money to buy frozen “seasoning mix” which is onions, celery and green peppers all diced up in a bag. Hell, I can do that myself! I started doing exactly that.
…and this would be the digital edition of the New York Times, right? Video, please.
How do you really have half an onion around for more than a few days at most?
Damn near every recipe uses onions- we’re far more likely to run out of onions than have a quandary about how to preserve part of one for later use. The idea that half an onion might actually lurk around in the fridge without being used is kind of a bizarre one to me.
That said, when we do only need half an onion, it just goes into a ziploc bag with the air out, and stored in the fridge for a few days until we need some more onions.
Usually happens when I need a slice of onion for a sandwich or something (I use red onion for that). Or if you are making one serving of salsa.
Yeah, a lot of people think that but it’ll never work and I’ll tell you why. It has to be “There’s No Business Like Show Business”.
Does it have to be an Ethel Merman impression?
If you cut off the outer 1/8 - 1/4" of a cut onion, you’ll get fresh onion - the cut will dry out; the inner part retains its moisture.
Coincidentally, I just happened to watch the How It’s Made episode on onions:
Concerns about bacteria are brought up twice, at 2:15 (onions with their ends cut off are rinsed with ozonated water to kill bacteria) and again at 3:27 (chopping an onion releases a lot of juice that apparently provides a good medium for bacterial growth).
I just cut it crosswise, skin on, and the part I don’t use, I place cut-face down on a plastic lid and set it back on the shelf in the fridge. It will keep just as well as a whole onion, since the face-down surface gets no air exposures. This works great for apples, too, and lots of other things. Good for several days, I presume you’re not talking about any more than that.
If you’re worried about bacteria, just be sure to use a clean knife and plastic lid, and don’t touch the surface with your hands.