An onions truth.

The chemistry lesson to my science students.   
                           Why onions make us cry?

Who has never sobbed while cutting an onion? While apart from those who have never cut one and beyond.  This is a little clarification...Chemistry DID

Inside the onion cells there are some chemical compounds that contain sulfur. When you cut an onion its cells are broken and those chemical compounds then endure a reaction that transmutes them into a more volatile sulfured product, which are released into the air.

These sulfured compounds react with the moisture in our eyes forming sulfuric acid, thus, producing a burning sensation. The nerves endings in our eyes are very delicate and they pick up on this irritation.  The brain reacts by telling our tear ducts to produce more water, to dilute the irritating acid. Therefore, one cries to keep eyes protected from the acid. 

There are several tricks to make onion-dicing less problematic:

-          Chop the onion under cold water. The volatile sulfured compounds will be released but then they react with the water, instead of reaching one’s eyes.

-          Can freeze the onion for 10 minutes before cutting it. The cold temperature of the onion will slow down the chemical reaction.