Why do onions make you cry?

Why do onions make you cry?

Onions contain an enzyme called lachrymatory-factor synthase, which is responsible for producing a chemical called syn-propanethial-S-oxide. When an onion is cut or peeled, this chemical is released into the air and reacts with the moisture in your eyes to form sulfuric acid. The acid irritates the sensitive tissues in your eyes, causing them to tear up in an attempt to flush out the irritant.

There are a few ways to reduce the amount of tearing that occurs when cutting onions. One method is to use a sharp knife, which will cause less damage to the cells of the onion and release fewer irritants. You can also try cutting the onion under running water, which will help to wash away the irritant before it reaches your eyes. Some people also find that wearing goggles or using a fan to blow the fumes away from your face can help to reduce tearing.

Alternate Answer for Why do onions make you cry?

When you cut into an onion, you release an enzyme called allinase that reacts with the amino acid sulfoxides present in the onion's cells to produce sulfenic acid. This chemical then rapidly decomposes into various volatile sulfur-containing compounds, including one called syn-propanethial-S-oxide. This compound is responsible for the characteristic pungent smell of onions, and it is also what causes tearing and irritation when it comes into contact with your eyes.

The syn-propanethial-S-oxide gas produced by onions can irritate the eyes and cause them to tear. This is a natural defense mechanism designed to protect your eyes from harmful substances. When the gas comes into contact with your eyes, it activates the trigeminal nerve, which is responsible for sensing irritation and pain in the face. This nerve sends a signal to the brain, which then causes the production of tears in an attempt to wash away the irritant.

There are a few things you can do to reduce or eliminate the tearing when cutting onions. One technique is to use a sharp knife, which will cause fewer cells to be damaged and release fewer of the irritating compounds. You can also try cutting onions under running water or using a fan to blow the gas away from your face. Finally, you can try wearing goggles or using special onion-cutting glasses that protect your eyes from the gas.