Why Do Onions Make You Tear?
Onions belong to a group of plants that absorb sulfur from the soil as they grow. This chemical is stored within the onion’s cell walls (or membranes). When those membranes are broken by our knives, they release a number of enzymes and a chemical called amino acid sulfoxide into the air.
These react with the water found on the surface of our eyes to create sulfuric acid … and that stings! Our body is wired to flush out unwanted chemicals or particles from our eyes with tears, so the second our brain senses that pain, it sends the signal to start tearing up.
How To Cut Onions Without Tearing
Use a sharp knife (the more efficient your chop, the less time you’ll spend exposed to those burning vapors. PLUS, a sharp knife will do less damage to the onion cells themselves, and slice through them rather than crushing them and releasing more chemicals into the air).
Keep your chopped onion pieces face down and away from your work space. Whether it’s putting them in a bowl away from where you’re chopping, or just moving them to the far side of your cutting board, keeping your distance from those tear-jerkers can make a big difference.
When you cut up onions, try to leave them in their original position as much as possible, so you don’t increase the surface area of exposed onion flesh. For example, when you first cut your onion in half, make sure both halves are placed cut-side down on the board. And don’t peel that section until you’re ready to cut into it!
Hacks That Actually Work
Drown Your Sorrows
What it is: Peel your onions and let them soak in a bowl of water for 10 minutes.
Why it works: The chemicals are drawn into the water, so there’s much less of it left to make you tear. However, this will also take away some of the characteristic taste of the onions, so be mindful of that when you cook with them.
The Vent Technique
What it is: Cut your onions under a kitchen vent (this works well if you have one built in above your stovetop).
Why it works: The air circulation directs the onion vapors away from your eyes, so that painful chemical reaction doesn’t happen..
Freeze ‘Em And (Don’t) Weep
What it is: 15 minutes before you’re ready to prepare your onions, stick them whole into the freezer. But don’t forget to take them out before they harden!
Why it works: The cold temperature minimizes the release of chemicals from the onion. This is because the enzymes are less reactive in cold and hot temperatures (which is why cooked onions never make you tear).
The Onion Goggles
What it is: It’s what it sounds like. Wear a pair of goggles while cutting onions. They actually sell goggles specifically designed for chopping onions, but a pair of swimming goggles will do the trick nicely.
Why it works: You guessed it, the goggles create a sealed barrier between your sensitive eyes and those harsh air-borne chemicals. That’s why some people say they don’t tear when they chop onions while wearing contact lenses.
So there you have it! Are there any other tips for preventing onion tearing that worked for you? We’d love to hear them!