Why Onions Make you Cry
If you have cooked with an onion, then you have probably cried over an onion (and everyone has a theory of how to avoid it - usually involving a humiliating action such as sticking your tongue out and crossing your eyes - and I have fallen for most of these in my time).
But do you know why we cry in the first place? Well, my onion loving friend, let me tell you… When you cut an onion you damage the cells, and the onion releases volatile gases in order to protect itself. These set off a series of chemical reactions that result in a gas called propanethial S-oxide being released. This gas irritates our eyes and our body reacts by releasing tears to dilute the gas, hence we cry. On the plus side, the more often you chop onions the amount of eye irritation is reduced, so the more you cook the less you’ll suffer!
If chopping a plate of onions everyday doesn’t appeal, then here are some methods that actually do work:
1. When peeling and chopping the onion, leave the root on.
2. Use a sharp knife to cut: this causes less cell damage so fewer irritants will be released.
3. Rinse your knife and chopping board in cold water frequently. The less gas hanging around, the drier your eyes will be.
4. Once cut, turn the onion over so the flat side sits on the chopping board and once chopped, move the onions into a prep bowl, or to a pan with a lid.
5. Chill your onions as this slows the release of the irritant.