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Author Topic: Why do onions hurt your eyes?  (Read 11267 times)

Offline tweener

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Why do onions hurt your eyes?
« on: 11/09/2004 03:22:33 »
I have a real problem with onions.  If I'm chopping a fairly strong one, my eyes shut themselves tight and won't open for several minutes.  Sometimes it makes me think I should put the knife down...

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Offline Exodus

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Re: Why do onions hurt your eyes?
« Reply #1 on: 11/09/2004 10:06:01 »
As i tell anyone with this problem... i support the use of snowboarding goggles whilst cutting and the early stages of cooking... sting free eyes!!!
 

Offline neilep

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Re: Why do onions hurt your eyes?
« Reply #2 on: 11/09/2004 10:16:16 »
Apparently Onions have sulfur compounds that cause the tears....I have a simple remedy...get someone else to chop them....also, try storing them in the refrigerator, or stick them i the freezer for half hour before use and use a really really sharp knife (on the onions of course !!)


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Offline Ylide

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Re: Why do onions hurt your eyes?
« Reply #3 on: 11/09/2004 20:24:20 »
A sharp knife alone will take care of the problem unless you're hypersensitive to them.  Use a good quality straight-blade chef knife to cut them and make sure it's honed before every use and sharpened a couple times a month.  Avoid serrated "ever-sharp" crap like the plague.  That stuff is complete junk.



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Offline tweener

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Re: Why do onions hurt your eyes?
« Reply #4 on: 14/09/2004 02:03:31 »
I guess I'm hypersensitive.  Sharp knives help some.  I've used swim goggles, but feel kinda wierd.  I've never tried the freezer, but even refrigerated onions hurt me.  One thing I've tried that really helps is to cut them under water.  Oh well.  

Mainly I was wondering about the chemistry involved.  Someone once told me that they emit a gas when damaged that combines with water to make a strong acid, thus making the eyes really burn.

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Offline chris

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Re: Why do onions hurt your eyes?
« Reply #5 on: 16/09/2004 15:52:09 »
Hi John

have a look at this previous post (dating back 2 years !) which describes the new, and old, theories of onion-related tears...:

http://www.thenakedscientists.com/forum/topic.asp?TOPIC_ID=23

Chris

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Offline Janedoe

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Re: Why do onions hurt your eyes?
« Reply #6 on: 17/09/2004 17:22:41 »
I never understood why you would want to eat something that could make you cry.  My solution give up the onions.

Yep! Yep!
 

Offline neilep

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Re: Why do onions hurt your eyes?
« Reply #7 on: 17/09/2004 21:37:38 »
John, here's a simple tip, buy one of those deep sea diving helmets, or a used space helmet...or perhaps...like they have in labs where they have dangerous chemicals in a sealed unit and you stick your arms in those rubber glove type things....simple !!...glad I could help.

Actually I did mention about the sulphur compounds that when they make contact with the water in your eyes some sort of reaction occurs.....It's obviously far more complicated than that, but I'm sure I read it somewhere...probably Readers Digest about ten years ago.

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Offline Donnah

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Re: Why do onions hurt your eyes?
« Reply #8 on: 19/09/2004 23:08:03 »
Food processors work well for this problem.
 

Offline tweener

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Re: Why do onions hurt your eyes?
« Reply #9 on: 21/09/2004 19:47:45 »
quote:
Originally posted by Donnah

Food processors work well for this problem.



Yea, but then I have to clean it.  I'm too lazy for that.

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Offline moses lawn

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Re: Why do onions hurt your eyes?
« Reply #10 on: 08/10/2004 23:27:34 »
Try cutting up the onion near to a flame, such as a gas cooker ring or a candle.
It seems to work.
 

Offline neilep

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Re: Why do onions hurt your eyes?
« Reply #11 on: 08/10/2004 23:35:37 »
....buy them ready chopped !!!...you can do that over here in good old blighty !!..surely you can get them over there....check out the freezer section !!

'Men are the same as women...just inside out !'
 

Offline GOD

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Re: Why do onions hurt your eyes?
« Reply #12 on: 18/10/2004 19:19:30 »
Yes, sorry abouteth that. When I created the onion I was in a bad mood. I decided that if thou was to enjoy said onion then thou shalt eyes weep upon thy cheek too.

I am GOD..You are Not..I don't exist !!
 

Offline Bin Laden

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Re: Why do onions hurt your eyes?
« Reply #13 on: 18/10/2004 19:22:36 »
Don't push your luck GOD, back to the sky where you belong you fool!

catch me if you can!
 

Offline Limpet chicken

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Re: Why do onions hurt your eyes?
« Reply #14 on: 11/12/2004 01:54:13 »
I believe the sulfur compounds hydrolyse to dilute sulfuric acid upon contact with eye moisture[:0]


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Re: Why do onions hurt your eyes?
« Reply #14 on: 11/12/2004 01:54:13 »

 

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