Atomic Fireballs were brought to us by the Ferrara Pan Candy Company, which is the best candy company because they also invented Lemonheads. If you make a super spicy candy and a super sour candy you're aces in my book.
Fireballs were released in the Cold War era of 1954, a perfect time for nuclear-themed candy, as America was certain of warhead-borne destruction coming our way [SIDENOTE: Looks like the similarly-named Warheads candy has a rather different provenance, as it came out of Taiwan in 1975]. I guess going in a blaze of cinnamon isn't the worst way to die.
The thing that interests me about Atomic Fireballs, though, is how damn spicy they are. But cinnamon isn't that spicy, is it? Bear with me science-wise for a second, then we'll get to the secret answer.
Cinnamaldehyde, the oil that makes cinnamon taste cinnamony, affects a receptor in your mouth called TRPA1. TRPA1 is part of the TRPA family of ion channels that detect when crazy chemical things go on; they're responsible for your reaction to raw garlic, horseradish, mustard oil, stuff like that. Kind of like irritant detectors.
While being an irritant is pretty bad, you probably swear that it's more than that. It's spicy, you promise! It's more than raw garlic! It's like, you don't know, hot peppers or something!
And you'd be right. Turns out Ferrara adds capsaicin to Atomic Fireballs to give them that little extra zing (or that lotta extra zing). Capsaicin is the compound that makes hot peppers spicy, and is found in everything from jalepeños to ...other hot candies. It reacts with a channel called TRPV1 (a.k.a. the capsaicin channel, which is what you should name your spicy-foods television network) which is good pals with the TRPA set.
The fun thing about TRPV1 (the spiciness receptor) is that instead of detecting chemicals, its primary purpose is to check the temperature. It's kind of like an alarm, in that when the receptor gets too hot it starts firing like crazy. How hot? About 43°C, or 110°F. So turns out that by eating something with capsaicin in it you're tricking your brain into thinking it's 110° in your mouth.
Also, look at this fun chart from Nature about what activates what receptors!
Go here if you want the science details, but from left to right it's peppers/camphor, camphor, a weird Chinese herb I'd never heard of called Andrographis paniculata, mint, and finally horseradish/cinnamon/garlic.
OK, so Atomic Fireballs are like a hot pepper in your mouth, great. But now the question is which hot pepper? Jalapeño vs. habanero is a pretty big thing if you're going to talk about this at your next cocktail/candy party.
Luckily, Ferrara is kind enough to let us know that Atomic Fireballs are 3500 on the Scoville scale, a scale that's used for measuring the spiciness of peppers. You pop on over to a chart at Wikipedia and see that they're in a respectable cayenne neighborhood; well above Jalapeños but not quite up to bird's eye chili strength.
Does that seem way too high to anyone else? You do not run around crying after you eat a Fireball. Maybe they just mean they use a chili powder with 3500 Scoville units when they put the candy together.
Anyway, now you can tell all your friends that Atomic Fireballs are just hot peppers with cinnamon sticks and sugar inside. If that doesn't make you want to order five pounds of them on Amazon, I'm not sure what will.