American pharmacist Wilbur Scoville invented the Scoville scale in 1912. Scoville created the scale by way of his Scoville Organoleptic Test, which he used to measure a pepper’s heat level. When conducting his test, Scoville mixed an alcohol-based extract of capsaicin oil from a pepper into a solution of sugar water and placed the solution onto the tongues of taste testers. Little by little, he diluted the solution with more water until his taste testers told him that it no longer tasted hot.
Scoville then assigned a number rating to that pepper based on how many times he had to dilute the solution to eliminate the heat. Jalapeño peppers, for instance, have a Scoville rating of 10,000, which means a jalapeño solution would have to be diluted 10,000 times before the heat was neutralized.
