Why do onions make us cry?
An onion enzyme that makes the eyes water
Scientists found the specific enzyme in onions that makes us cry while chopping them.
Ig Nobel 2013
Everyone assumed the tear-making chemical in onions simply formed by itself when you cut one. This team went looking and found a dedicated enzyme doing the job.
They named it lachrymatory-factor synthase, and switching it off could, in principle, give us onions that don’t make you weep. Chopping onions would lose its reputation as the saddest kitchen task.
The onion was crying on purpose all along.