Every chili has a score, and getting it once required some very brave volunteers.
The famous chili heat scale is named after the man who invented it. What was his day job, behind a drugstore counter?
Pharmacist Wilbur Scoville, an American pharmacist, created the test in 1912, and the heat units still carry his name.
To rate a pepper, the original test didn't use a thermometer. What sweet drink was the pepper extract watered down into, again and again?
Sugar water Dried pepper was soaked in alcohol, then diluted in sugar water until most of a five-person tasting panel could no longer feel the burn.
Those trained tasters had a big problem after just a few samples. What happened to them?
Their mouths stopped feeling heat Palates quickly go numb to the burn, and tasters differ so much that results could swing by half from one lab to another.
The hottest thing ever rated on the scale isn't a pepper at all. Where does it come from?
Plant sap Resiniferatoxin, found in the sap of spurge plants, is a thousand times hotter than capsaicin and would score around 16 billion heat units.
Modern labs no longer need brave tasters to rate a chili. What does the job instead?
A lab machine A machine now measures the exact amount of heat chemicals in a pepper, and the result is converted back into Scoville units so the old scale lives on.
