Conquering the tear-inducing terror of chopping onions

Beneath the onion’s unassuming layers lurks a secret weapon of mass tear-gasification. But fear not foodies! With a little scientific know-how, you can conquer the dreaded onion tears and reclaim your culinary throne.

Understanding the EnemyFirst, let's meet the villain: a volatile enzyme called lachrymatory-factor synthase (LFS). When onion tissue is disrupted, LFS breaks down other compounds to produce syn-propanethial-S-oxide (SO), a gas so pungent it would make a skunk wince. SO readily ascends to your unsuspecting eyeballs, where it binds to tear-producing epithelial cells, triggering a deluge of watery defences.

So, what can we do about SO?

Weapon #1: The Elemental ShieldFire! Lighting a candle near your chopping board can neutralise airborne SO with its competing carbon dioxide fumes. Imagine it as a firewall, deflecting the tear gas before it reaches your eyes.

Weapon #2: The Visual VanguardGoggles may not be the most kitchen chic, but they're an effective barrier against oniony. Channel your inner mad scientist, and rock goggles with pride as the rubber sealed lenses protect you from the fumes.

Weapon #3: The Hydrogen HeroChopping onions under running water also works as the water acts as a barrier helping you conquer the onion kingdom, tear-free and triumphant. But do note that the trick here is to use running water - just putting a bowl of water next to you won’t work.

There are lots of other wives tales about ways to stop your eyes watering when chopping onions, but these are just a few that have science’s seal of approval.

P.S. If all else fails, there's always the trusty onion chopper. Just don't tell the onions we told you. They might cry.

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