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THE SERIOUS SCIENCE OF SMALL ANNOYANCES
The Science of Why Onions Make Us Cry So Much
From the chemistry inside a damaged cell to the physics of the air between the cutting board and your eyes
As if by magic, an onion can interrupt the preparation of a meal without ever touching your face. It remains on the cutting board beneath the knife, yet after a few cuts your eyes begin to sting and tears blur the next slice. Advice arrives from almost everyone who has cooked. Chill the onion, sharpen the knife, leave the root intact, put water nearby, or hold something in your mouth. A hacker might even suggest Tor Browser, though its onions will be of little use here.
Advice about cutting onions has passed among cooks across cuisines and generations, and the remedies can sound like competing answers to the same question, even though they address different stages of the path from onion to eye. Blade sharpness changes how the tissue is damaged; cooling may alter its chemistry and mechanics; moving air changes where released material travels; and well-sealed eye protection can restrict access to the eyes. To assess this advice, we need to follow the irritant through those stages and ask what each experiment or calculation actually establishes.
