Today’s Google Doodle, an animation (access it by clicking on the screenshot blow), honors the 151st birthday of Wilbur Scoville (1865-1942), an American chemist. In 1912, Scoville devised the “Scoville Organoleptic Test,” a way to quantify the spiciness of chile peppers. Now, of course, breeders all over the world compete to grow the spiciest chiles with the highest Scoville rating.
Here’s a video of the animation; Google’s story about the making of the Doodle is here.
In 2013 the New Yorker had a nice article, “Fire-Eaters” (free online) about breeders’ informal competition to grow the hottest chile. It ends with the teaser that Butch Taylor, a Louisiana plumber who breeds chiles as a hobby, was producing a really wicked one:
Before we came inside, Taylor had shown me his greenhouse, where he tends his most precious plants. A single bush dominated the small hut. Hanging from its branches were an assortment of pods, some of them deep red and some of them a faint green. The plant, which was not yet stable, was the third generation of an accidental cross of a 7-Pot Jonah and, most likely, a Trinidad Scorpion Butch T. Taylor was calling it the WAL—the Wicked-Ass Little 7-Pot. He shook a branch, unleashing a swarm of flies, and picked a pod from the stem. “Just off the top of my head, the first one I tasted, I’d say two million Scovilles,” he said. “But it may just be a freak of nature. You get those now and then.”
Below is Wikipedia’s diagram of the Scoville scale, with the Carolina Reaper still holding out over the Trinidad Scorpion Butch T pepper. Here’s how the ratings are achieved, a combination of objective methodology and subjective assessment (unavoidable when it comes to matters of taste perception):
In Scoville’s method, an exact weight of dried pepper is dissolved in alcohol to extract the heat components (capsinoids), then diluted in a solution of sugar water. Decreasing concentrations of the extracted capsinoids are given to a panel of five trained tasters, until a majority (at least three) can no longer detect the heat in a dilution. The heat level is based on this dilution, rated in multiples of 100 SHU.
A weakness of the Scoville Organoleptic Test is its imprecision due to human subjectivity, depending on the taster’s palate and their number of mouth heat receptors, which varies greatly among people. Another weakness is sensory fatigue the palate is quickly desensitised to capsaicins after tasting a few samples within a short time period. Results vary widely, ± 50%, between laboratories.
Notice that jalapeño peppers, which most people consider hot, come in at a wimpy 1000-4000 Scoville units.
The active ingredient in chiles—the stuff that makes them hot—is the compound capsaicin, although other related compounds (“capsaicinoids”) contribute to the heat as well. Below is the diagram of a capsaicin molecule; it and its relatives probably evolved as protective compound in wild chiles, deterring attacks by herbivores and fungi. Humans have taken advantage of that protection by simply breeding for more and more of the hot metabolites.
Apparently birds, who disperse wild pepper seeds, don’t react to capsaicinoids, while mammalian herbivores, who would crunch the seeds and destroy the plant’s ability to pass on its genes, react adversely. This is probably not a case of true coevolution; I suspect that plants producing fleshy bits containing capsacinoids (seeds don’t themselves contain the compounds) left more genes than those that didn’t simply because birds already lacked the receptors for the compounds while mammals had them.
There is in fact, a Wikipedia article about Guinness’s Official World’s Hottest Pepper, the Carolina Reaper, also known as HP22B, bred in South Carolina and coming in at a scorching 1,569,300 Scoville units. (One was rated at 2.2 million Scoville Units.) Here’s what they look like:
You can buy seeds and Reaper Hot Sauce from the PuckerButt Pepper Company (sauce here; hottest seeds here). I dare any reader to try one of these (warning: do not ingest “Reaper Venum” directly):
If you want something hotter, there are pure capsicum extracts, hotter than the hottest pepper available, here, as well as a panoply of hot sauces having various degrees of tongue-destruction.
Oh, and here’s Scoville himself, a man who had no idea what monster he’d created:
