Two days ago I was peeling onion and then painful tears started gushing out of my eyes, my eyes were hurting during that period, cutting onions has turned out to be one of my fears while cooking. I guess you have had that same experience, today am going to tell you why onion makes you shed tears.
Onion ( Allium cepa) is a vegetable which consists of so many compounds especially(sulphuric compounds), as an onion is sliced it releases a class of enzyme called allinases which produces a range of compounds as a defense mechanism, one called the lachrymatory factor, from Latin meaning lacrima, it irritates the eye and then stimulates the tear glands to produce tears.
When an onion is crushed or cut, large amounts of volatile sulphuric compounds will be released which will be broken down by allinase.
To avoid shedding tears while cutting onions scientists advice that the onion be cut under water as the compounds in onions are water soluble, this will prevent them from entering the eye.
A hack which works is chewing gum while cutting the onion; I tried that and am happy to say that it worked.