Overview
- Researchers led by Cornell University built a guillotine-like cutter and used high-speed imaging to visualize and quantify droplets released during onion slicing, reporting the results in PNAS.
- Droplets emerge in a forceful initial outburst when the blade breaches the outer skin, with measured speeds of roughly 5–40 meters per second and heights up to about 60 centimeters.
- Systematic trials showed that blunter blades and faster cutting produced more droplets with higher kinetic energy, whereas sharper blades and slower motions reduced spray.
- The findings carry food-safety implications as droplets can encapsulate surface pathogens, suggesting that knife maintenance and gentler technique may limit aerosolized spread in kitchens.
- Reports diverge on refrigeration, with one test finding no significant change after chilling and another noting more droplets from cooled onions, and the team plans follow-up studies on varieties and pathogen transmission.