Overview
- Cornell-led research published in PNAS provides direct evidence that cutting onions ejects microscopic liquid droplets that aerosolize irritant sulfur compounds, adding a physical pathway to the long-accepted chemical gas explanation.
- A guillotine-like setup and high-speed cameras recorded onion cell fluid blasting out at more than 140 kilometers per hour before breaking into a mist that increases the chance of eye exposure.
- Knife condition proved critical in tests, with dull blades boosting both the number and speed of droplets, whereas sharp knives and slower cuts reduced emissions.
- Cooling the onions did not curb droplet formation in the experiments and instead increased the amount released, contradicting common kitchen advice about chilling.
- The authors caution that the same droplet-generation mechanism could help spread pathogens from contaminated raw foods during preparation, underscoring a potential food-safety concern that merits further study.