Why do you 'cry' when slicing onions?

Each time you chop onions, you have to find ways to cut them together so that you don't make eye contact with the onions so you don't have to 'shed tears'. Why is this happening? What are some tips to avoid tears when chopping onions?

You are happily slicing onions and preparing for dinner then Boom! Your eyes are hot and tears are coming down. Perhaps your eyes are so spicy that you have to stay away from the onions! Why onions can make you so uncomfortable? It actually involves an interesting biochemical reaction.

Tears when chopping onions are a phenomenon many people encounter when cooking.

Before appearing in your kitchen, onions absorb nutrients from the sun and minerals from the soil. It turns out that onions specifically absorb sulfur , which they use in amino acids . When you cut onions, you break down the cell layers, releasing their fluid. The enzymes that were broken down first encounter sulfur-rich amino acids and form unstable sulfenic acid , which then rearranges into a substance called syn-propanethial-S-oxide . This stealthy chemical is volatile, and causes a burning sensation when it comes up from a cutting board and makes contact with your eyes. To keep your eyes from getting hurt, your brain quickly activates the tear glands to wash away irritants.

So what can be done to reduce the chemical reaction with onions? Certain types of onions, especially sweet ones, have less sulfur than others and thus cause less eye irritation. You can also leave the onions in the refrigerator before slicing ; This will slow down the activity of the enzymes responsible for that unfortunate chemical reaction sequence.

Another trick - like lighting a match, eating bread while slicing onions, or breathing through your mouth - is considered less effective, but despair is the mother of creativity? Try it if necessary.