Why exactly do onions make my eyes burn when I slice them?!


Question: Does the onion release something into the air that acts as an irritant?

It actually gets to the point where I need to stop slicing and run to go wash my eyes out. I know I'm not the only person in the world this happens to..........

Any information and advice would be appreciated.

Thanks,

Primo


Answers: Does the onion release something into the air that acts as an irritant?

It actually gets to the point where I need to stop slicing and run to go wash my eyes out. I know I'm not the only person in the world this happens to..........

Any information and advice would be appreciated.

Thanks,

Primo

the onion burns your eyes because it realeases a gas as a defense mechanism. The onion thinks it is being attacked and the gas is released and goes straight to things that are moist. With most people this is their eyes. To avoid this, chill the onion and all the tools you will be working with. Also set out a glass of ice water. Since the glass is not as tall as your eyes it will be the closest thing to the gas from the onion, therefore not as much will reach your eyes. If your eyes get irritated after all of this, take breaks and stick your head in the freezer for a couple of seconds. This may sound funny but the cold air in the freezer quickly relieves your eyes. This may sound funny but at my school we walk into the fridge and stand there until its better, it only takes a couple of seconds. Hope this helps!!

You are exactly right. It releases a gas that irritates your eyes. Try chilling your onions first. Some people put a piece of bread in their mouths, others a match. Some wear swim goggles.

Just chill the onions first.

Onions cells contain small amounts of propanethiol S-oxide. When you cut one open, this compound mixes with enzymes that release a sulfur compound which is itself not noxious. However, when it encounters the water in our tear ducts, it creates sulfuric acid which is a strong irritant. Rubbing ones eyes will only make things worse if some of the compound has adhered to the skin while cutting the onion.

Some people have noticed that running cold water on your wrists prior to cutting an onion can reduce the irritation. The explanation for this is related to putting cold keys on your back to reduce a nosebleed. The cold sensation makes blood vessels in the nasal passages constrict. The route to the tear glands is through the nose and constriction of the blood vessels may slow this process down.

As onions are sliced, cells are broken, allowing enzymes called alliinases to break down amino acid sulfoxides and generate sulfenic acids. Sulfenic acids are unstable and spontaneously rearrange into a volatile gas called syn-propanethial-S-oxide. The gas diffuses through the air and eventually reaches the eye, where it reacts with the water to form a diluted solution of sulfuric acid. This acid irritates the nerve endings in the eye, making them sting. Tear glands produce tears to dilute and flush out the irritant.

Supplying ample water to the reaction prevents the gas from reaching the eyes. Eye irritation can, therefore, be avoided by cutting onions under running water or submerged in a basin of water. Rinsing the onion and leaving it wet while chopping may also be effective. Another way to avoid irritation is by not cutting off the root of the onion, or by doing it last, as the root of the onion has a higher concentration of enzymes. Chilling or freezing onions prevents the enzymes from activating, limiting the amount of gas generated. Using a sharp blade to chop onions will limit the cell damage and the release of enzymes that drive the irritation response. Having a fire, such as a candle or a burner, will help as the heat and flames will draw in the onion gas, burn it, and then send it up with the rest of the flame exhaus. In the heat, the chemical changes such that it no longer irritates the eyes.

The pierced onion cells release a sulfur compound, thio-propanal-s-oxide, which irritates the eyes.

Burn one or two candles next to your cutting board where you are cutting the onions and the flames will eliminate this from reaching your eyes.

You are probably feeling guilt over mercelessly slaughtering an onion. I hope you're happy with yourself

Hey brother
I get this too
Real badly
I find that when I cut the onion into its big chunks under water that it helps a bit. But i'll also take your first answer and try chilling it. Most of the time mine comes out of the fridge though.. but still its worth trying. I may also try the burning the candle or wetting my wrist.. Won't hurt to give each a shot.
Personally I think I may have a bad allergic reaction to onions, because my eyes feel all swollen and irritible long after I've chopped or cooked with them. If i have to put on contacts then its HORRIBLE..
Anyways brother :)
Happy cooking

Ur sis
sandy





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