onions & crying

[Lakewood]

Why do onions make you cry when you slice them?

[B00]

now I'm no foody expert (except in the eating of- of which I excel!) but I'm sure it's to do with the acid in them which squirts out.

[Xollob]

This from Wikipedia:

"As onions are sliced, cells are broken open. Onion cells have two sections, one with enzymes called alliinases, the other with sulfides (amino acid sulfoxides). The enzymes break down the sulfides and generate sulfenic acids. Sulfenic acids are unstable and decompose into a volatile gas called syn-propanethial-S-oxide. The gas then dissipates through the air and eventually reaches one's eye, where it will react with the water to form a mild solution of sulfuric acid. The sulfuric acid irritates the nerve endings in the eyes, making them sting. The tear glands then produce tears in response to this irritation, to dilute and flush out the irritant."

[Champagne]

Oooh! Ooh! Miss! I know this!

When you slice into an onion the enzymes are released (as with all vegetables). However, onions contain certain enzymes which, on contact with air, alter themselves into acidic gases. This gas then becomes airborn and can reach the eyes. The gas then reacts with the water in your eyes and alters again into a very mild sulphuric acid. Your eyes react to this and 'cry' in order to rinse the acid away.

Do I get a gold star? :o)

[Kay]

Lakewood,Onions dont make us cry,they just make our eyes water:--) Try peeling em underwater,not you..the onions,,lol or put a teaspoon in your mouth both work well.

[jan15]

I find that if I keep onions in the refrigerator, and take them out just before slicing, then it doesn't make me cry.

[jan15]

... but I don't know why chilling makes a difference.