Anyone who has ever cut an onion is well aware of the burning sensation it causes in our eyes, making us cry. But what is the reason for this?
When we cut the onion, some cells break up, letting some compounds escape. One of these compounds is sulfur. This compound, when in contact with atmospheric air, turns into a gas and spreads through the environment.
Because of the acid in contact with our eyes, the river of tears comes.
When this gas comes into contact with our eyes, it reacts with water and forms a solution of sulfuric acid.
This acid causes a lot of irritation in our eyes, causing them to burn. With this burning sensation, our tear glands begin to produce tears in order to wash our eyes, in an attempt to eliminate the sulfuric acid that caused the burning.
Some people use various means so that the onion doesn't irritate their eyes.
In order to cut the onion without crying, some people use some means, such as:
⇒Cut the onion in a basin of water, or under the faucet;
⇒Put to onion inside the refrigerator so that it is very cold before cutting it, or cutting it with a cold knife;
⇒Use very sharp knives.
All ways to cut the onion mentioned above are intended to reduce the action of compounds that, after reacting, cause eye irritation.
by Paula Louredo
Graduated in Biology
