# Keeping part of an onion for future use **URL:** \ **Category:** Cafe Society\ **Created:** [September 9, 2014, 9:45pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023 "2014-09-09T21:45:27Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![ThelmaLou](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thelmalou/32/390_2.png) [@ThelmaLou](https://boards.straightdope.com/u/ThelmaLou)\ **Post date:** [September 9, 2014, 9:45pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/1 "2014-09-09T21:45:27Z")
How do you all store part of an onion when you only use, say, half of it? I’m assuming you refrigerate it, but do you wrap it in foil/plastic wrap/parchment? Or put it in a jar/tupperware/disposable plastic container/Ziploc bag ? If I’m making one sandwich or something where I only need part of an onion, I never know the best way to save it for future use. BTW, when googling this topic, I came across a [FALSE BELIEF](http://www.snopes.com/food/tainted/cutonions.asp) that cut onions are bacteria magnets, readily contaminated, and you should never save part of an onion or you will die if you eat it. Not true. ---
**Author:** ![Gordon\_Urquhart](https://avatars.discourse-cdn.com/v4/letter/g/db5fbb/32.png) [@Gordon\_Urquhart](https://boards.straightdope.com/u/Gordon_Urquhart)\ **Post date:** [September 9, 2014, 9:50pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/2 "2014-09-09T21:50:23Z")
I use half or a quarter of an onion all the time, reserving the remainder in a plastic sandwich bag (not a ziplock or equivalent) and not taking great pains to seal the bag prior to putting it in the right corner of the top shelf of the refrigerator. I read, somewhere, sometime, to always save the root end of the onion for last, and that practice has never let me down (although for all I know, dividing an onion while humming _The Star Spangled Banner_ and standing on one leg will leave the remainder equally fresh). ---
**Author:** ![Lamar\_Mundane](https://avatars.discourse-cdn.com/v4/letter/l/85f322/32.png) [@Lamar\_Mundane](https://boards.straightdope.com/u/Lamar_Mundane)\ **Post date:** [September 9, 2014, 9:52pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/3 "2014-09-09T21:52:41Z")
On my belt. ---
**Author:** ![El\_Kabong](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/el_kabong/32/496_2.png) [@El\_Kabong](https://boards.straightdope.com/u/El_Kabong)\ **Post date:** [September 9, 2014, 9:54pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/4 "2014-09-09T21:54:11Z")
Caveat: I’m a complete philistine. I just keep 'em in the vegetable bin of the fridge, in the plastic bag I brought them home in, until I either use them up or they go moldy. I likes me some onion, though , so they usually get used up before they go off. > [@ThelmaLou](#): > > BTW, when googling this topic, I came across a [FALSE BELIEF](http://www.snopes.com/food/tainted/cutonions.asp) that cut onions are bacteria magnets, readily contaminated, and you should never save part of an onion or you will die if you eat it. Not true. Right; if that were true I’d be dead dozens of times over. ---
**Author:** ![bobot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bobot/32/21622_2.png) [@bobot](https://boards.straightdope.com/u/bobot)\ **Post date:** [September 9, 2014, 9:57pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/5 "2014-09-09T21:57:39Z")
When I dice an onion, I dice the entire thing. The pieces are placed into a small, tightly lidded plastic container, which is kept in the fridge. I get well past a week, sometimes 2 weeks goodness from the pieces. ---
**Author:** ![ThelmaLou](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thelmalou/32/390_2.png) [@ThelmaLou](https://boards.straightdope.com/u/ThelmaLou)\ **Post date:** [September 9, 2014, 10:05pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/6 "2014-09-09T22:05:05Z")
> [@bobot](#): > > When I dice an onion, I dice the entire thing. The pieces are placed into a small, tightly lidded plastic container, which is kept in the fridge. I get well past a week, sometimes 2 weeks goodness from the pieces. I like this. ---
**Author:** ![Suburban\_Plankton](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/suburban_plankton/32/219_2.png) [@Suburban\_Plankton](https://boards.straightdope.com/u/Suburban_Plankton)\ **Post date:** [September 9, 2014, 10:36pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/7 "2014-09-09T22:36:15Z")
I had never heard of the “cut onions will ill you” belief until fairly recently when \*\*Rhiannon8404 \*\*told me about it (she doesn’t believe it herself, but was aware that some people do). I often use part of an onion when making hamburgers, and simply wrap the rest up in a couple layers of plastic wrap. I do always make certain these days to alert the household that I’m placing a packet of certain death into the fridge…I figure that lets me off the hook, right? ---
**Author:** ![Aangelica](https://avatars.discourse-cdn.com/v4/letter/a/b2d939/32.png) [@Aangelica](https://boards.straightdope.com/u/Aangelica)\ **Post date:** [September 9, 2014, 10:52pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/8 "2014-09-09T22:52:40Z")
I have a ridiculous plastic container that is shaped like an onion that I stick the onion remainders in until the next time I need onions. It’s re-usable, dishwasher safe, and since all it _ever_ contains is onions, I do not have to worry about contaminating other tupperware objects with the plague of Lingering Onion Aroma. I’m pretty sure onions are no more bacteria magnets than any other uncontained food item. Also, I’ve been storing partial onions in my fridge for decades without ever being rendered ill by by one. ---
**Author:** ![SeaDragonTattoo](https://avatars.discourse-cdn.com/v4/letter/s/df705f/32.png) [@SeaDragonTattoo](https://boards.straightdope.com/u/SeaDragonTattoo)\ **Post date:** [September 9, 2014, 11:00pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/9 "2014-09-09T23:00:09Z")
I just use a baggie and squeeze whatever air out without trying too hard. A half onion lasts weeks that way. ---
**Author:** ![teela\_brown](https://avatars.discourse-cdn.com/v4/letter/t/d9b06d/32.png) [@teela\_brown](https://boards.straightdope.com/u/teela_brown)\ **Post date:** [September 9, 2014, 11:00pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/10 "2014-09-09T23:00:40Z")
> [@bobot](#): > > When I dice an onion, I dice the entire thing. The pieces are placed into a small, tightly lidded plastic container, which is kept in the fridge. I get well past a week, sometimes 2 weeks goodness from the pieces. This is a good idea. I’ve been keeping the remaining half or quarter onion whole in a ziploc bag, but I don’t see any reason not to dice the whole thing and save some time later in the week when I need chopped onions again. ---
**Author:** ![chiroptera](https://avatars.discourse-cdn.com/v4/letter/c/df705f/32.png) [@chiroptera](https://boards.straightdope.com/u/chiroptera)\ **Post date:** [September 9, 2014, 11:01pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/11 "2014-09-09T23:01:01Z")
I don’t wrap it at all; I just put it cut-side down in the fridge. It might dry out a bit but for cooking, that won’t matter. Or I dice the whole thing and put the unused portion in a zip-lock bag or container. Either way it lasts at least a week and hasn’t killed anyone yet. ---
**Author:** ![wonky](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wonky/32/393_2.png) [@wonky](https://boards.straightdope.com/u/wonky)\ **Post date:** [September 9, 2014, 11:04pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/12 "2014-09-09T23:04:27Z")
I pop it into a plastic container. I have small ones that work really well for onions and the like. ---
**Author:** ![TriPolar](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/tripolar/32/3008_2.png) [@TriPolar](https://boards.straightdope.com/u/TriPolar)\ **Post date:** [September 9, 2014, 11:12pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/13 "2014-09-09T23:12:36Z")
I wrap it tightly in plastic. The little produce bags from the grocery work fine. ---
**Author:** ![Biggirl](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/biggirl/32/3294_2.png) [@Biggirl](https://boards.straightdope.com/u/Biggirl)\ **Post date:** [September 9, 2014, 11:17pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/14 "2014-09-09T23:17:11Z")
Plastic container or plastic wrap. Whichever’s handiest. ---
**Author:** ![araminty](https://avatars.discourse-cdn.com/v4/letter/a/b5e925/32.png) [@araminty](https://boards.straightdope.com/u/araminty)\ **Post date:** [September 9, 2014, 11:44pm UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/15 "2014-09-09T23:44:32Z")
I usually use a zip-lock. And I like to leave the remainder whole (unsliced/diced) - how will I know what form factor I’ll want for my onion in the future? I also think the more cut up it is, the more cell walls are broken, leading to deterioration of taste and nutrients. ---
**Author:** ![HelenGawn](https://avatars.discourse-cdn.com/v4/letter/h/a88e4f/32.png) [@HelenGawn](https://boards.straightdope.com/u/HelenGawn)\ **Post date:** [September 10, 2014, 12:20am UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/16 "2014-09-10T00:20:25Z")
> [@chiroptera](#): > > I don’t wrap it at all; I just put it cut-side down in the fridge. It might dry out a bit but for cooking, that won’t matter. Or I dice the whole thing and put the unused portion in a zip-lock bag or container. > > Either way it lasts at least a week and hasn’t killed anyone yet. Thank you! Growing up I saw my mom do this with tomatoes (I assume you mean on a small plate). An old boyfriend shamed me out of it, but now I have proudly reclaimed my heritage. ---
**Author:** ![Heffalump\_and\_Roo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/heffalump_and_roo/32/7691_2.png) [@Heffalump\_and\_Roo](https://boards.straightdope.com/u/Heffalump_and_Roo)\ **Post date:** [September 10, 2014, 12:31am UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/17 "2014-09-10T00:31:19Z")
When I’m not being lazy, which is most of the time, I put it in a foodsaver container and take out all the air from the container. That way, the refrigerator doesn’t smell like onion. I learned the hard way that spoiled onions reek. It should have been obvious, but the level of reek surprised me. Foodsaver saved onions last quite a while, at least a week. When I’m being lazy, I put the cut onion in a regular plastic tightly-lidded container. I try to eat them or throw them out pretty quickly. ---
**Author:** ![PapSett](https://avatars.discourse-cdn.com/v4/letter/p/ecc23a/32.png) [@PapSett](https://boards.straightdope.com/u/PapSett)\ **Post date:** [September 10, 2014, 12:43am UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/18 "2014-09-10T00:43:22Z")
Whatever onion I have left over, I dice and store in the freezer in a ziplock. I can then use whatever amount I need. ---
**Author:** ![johnpost](https://avatars.discourse-cdn.com/v4/letter/j/f17d59/32.png) [@johnpost](https://boards.straightdope.com/u/johnpost)\ **Post date:** [September 10, 2014, 1:41am UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/19 "2014-09-10T01:41:20Z")
cutting ahead of time does diminish it. remainders whole and tightly wrapped. ---
**Author:** ![GrumpyBunny](https://avatars.discourse-cdn.com/v4/letter/g/bc8723/32.png) [@GrumpyBunny](https://boards.straightdope.com/u/GrumpyBunny)\ **Post date:** [September 10, 2014, 1:51am UTC](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023/20 "2014-09-10T01:51:22Z")
> [@SeaDragonTattoo](#): > > I just use a baggie and squeeze whatever air out without trying too hard. A half onion lasts weeks that way. Ditto. I even use \*generic \*baggies! I also put the cut side down on a folded paper towel. I don’t know what this accomplishes, I think I only do it because my mom does. **PapSett** – I didn’t know you could home-freeze onions. I shall try that with leftover diced fresh onions! I normally buy a bag of frozen onions for cooking. Hey, I’m single and things in the crisper die at inopportune times. [Next page](https://boards.straightdope.com/t/keeping-part-of-an-onion-for-future-use/698023.md?page=2)