This enticing slow-motion video from the University of Central Florida shows citrus zest right as it’s squeezed, leading to a high-speed ejection of the citrus oil inside tiny cells within the zest (take a close look at a lemon skin sometime to spot them).
The resulting jets of fragrant oil can travel at 10 meters per second, and look like “watching a hundred fireworks fired in random sequence at the finale of a show,” says Andrew Dickerson, assistant professor of mechanical and aerospace engineering at the university.
This profuse and high-velocity projection of citrus oil is why the bartender twists the lemon zest over your martini, and what is ignited when “flaming a twist.” But Dickerson and his colleague Nicholas Smith see potential applications for medicine, where composite materials mimicking citrus zest could be used for drug delivery—in, say, one-time-use inhalers.
