July 13, 2021, 3:16 pm | Read time: 2 minutes
Anyone who has ever chopped onions knows the phenomenon: After a while, you cry like a baby–no matter how emotional you are. Why do our eyes tear up, and how can we counteract it?
Onions are popular in the kitchen, but chopping them is often not much fun. Sometimes you have to pause and turn away because your vision is blurred by tears. After a brief moment, you continue, and the onion is finally diced. Whether your eyes just get moist or tears flow freely, some simple tricks can help. How can you chop onions without crying?
Why Do We Cry When Chopping Onions?
When you cut an onion, it releases gases. This triggers a chemical reaction designed as a natural defense mechanism for the vegetable, protecting it from predators. But the gas mixture also has an irritating effect on humans.
Specifically, it involves the enzyme alliinase reacting with the sulfur-containing amino acid isoalliin. This produces propanethial-S-oxide, which quickly evaporates, rises, and reaches the eyes. Tearing is a natural defense mechanism of the eyes to flush out irritants.
Related: Harvesting and Properly Storing Onions
Avoiding Tears When Chopping Onions
With a few tricks, you can chop onions without crying–or at least reduce it. It starts with preparation.
- The knife should definitely be sharp. A dull knife crushes the onion more, damaging more cells from which the irritating gases escape.
- Before chopping, it helps to moisten the cutting board. The same goes for the knife and hands. Water binds the gas, preventing it from rising easily.
- You can also peel the onion under running water. Alternatively, you can place it in a bowl of water and peel it there.
- If you chop the onion while sitting, such as at the kitchen table, the gases don’t rise directly into your eyes.
- It’s also beneficial to breathe only through your mouth while chopping. This protects the mucous membranes from irritation.
- It’s often recommended to keep some water in your mouth while chopping. This can also help prevent your eyes from tearing.
- If you turn on the kitchen exhaust fan while chopping onions, the fumes dissipate faster. Otherwise, you can chop near an open window.
- Even if it sounds silly–wearing protective goggles can shield your eyes from the gas. Perhaps you have an old pair of swim goggles lying around.