There's a Surprisingly Simple Way to Stop Crying Over Your Onions

Usually, the chemical mist released when onions are chopped – propanethial S-oxide – makes our eyes water. Now scientists have found a simple way to keep those tears to a minimum.

In experiments by researchers from Cornell University in the US, sharper blades and slower cuts significantly reduced the amount of onion mist given off during preparation, keeping eyes drier and kitchen surfaces safer.

Biomechanist Zixuan Wu and team used a mini guillotine, a high-resolution camera, and sensors to carefully track the droplets expelled as onions were cut, comparing mist characteristics against knife sharpness, chopping speed, and cutting force.

"We found out the speed of the mist coming out is much higher compared to the speed of the blade cutting through," says physicist Sunghwan Jung.