We all have that friend: The one who always has to up the spice ante, swearing whatever pepper they’re biting into isn’t even that hot, as sweat pours down from their face.
Sure, we might ignore their pleas for glasses of milk or all those streaming tears to take them at their words, but there’s actually a way to objectively prove how hot their meal is – no ego test necessary.
Somewhere around 1912, the American pharmacist Wilbur Scoville was sick of letting those dare-devil friends steal the show, and he decided to do something about it once and for all. (It’s possible he also had other reasons to pursue his hot pepper research.)
The result is what we today call the Scoville Organoleptic Test, a scientific attempt to measure the amount of heat in any given chili pepper.
The official test is an interesting mix of subjective and objective research, but it’s been widely used to rank the heat of chili peppers worldwide nearly since its invention.
It all starts when a specific amount of dried pepper is dissolved into alcohol, in order to extract the heat-producing components – otherwise known as capsaicinoids.
After mixing the raw capsaicinoids with a sugar water solution, the final product is then given to a panel of five experts. The group tastes the paste, then notes whether they can still detect heat. If they can, a new batch is offered up, with a diluted amount of the capsaicinoid mixture.
The process continues until at least three of the panel members declares they can no longer taste any spice in the mix. At that point, a rating is given for the pepper, based on the number of times the concentration had to be diluted to remove the sensation of heat – and multiplied by 100.
For example, a jalapaño ranks as a 10,000 on the Scoville Scale. That means its capsaicinoid solution had to be diluted 1,000 times in order for a majority of the panel to no longer taste its heat.
Each round of dilution is called a Scoville Heat Unit (SHU), and the cumulative total is used to rank the hotness of the peppers involved, with higher numbers representing hotter peppers.
The scale has been heavily criticized over the years for the impreciseness of its human panel – especially given that the detection of heat can rely on any number of factors, including the amount of heat receptors in the mouth, which varies widely from person to person, and the general palate fatigue that comes from trying similar foods over and over again.
Still, Scoville has stood the test of time regardless, and is widely referred to today when attempting to categorize the spice factor of hot peppers.
And some of those ranking high on the scale may surprise you.
Those boundary-pushing friends we all have at the restaurant have a counterpoint in the agricultural world.
Pepper growers are constantly trying to expand the power of the plant, and all the potential heat it could deliver, and so new peppers are put through the Scoville Organoleptic Test all the time.
Indeed, the ranking of the hottest peppers is ever-changing, but there are still a few standbys we can always rely on to get our hearts racing – including (in order from mildest to hottest):
The colorful capsicums barely register as a pepper at all, pulling the lowest SHU score possible: A big, fat zero.
It’s no wonder they’re also called sweet peppers. But we still have to love them for trying.
The popular Mexican chilis are a great choice for those with a sensitive pallet, ranking at a mild 2,000 SHU.
They may be bigger in stature than most other peppers, but in the world of hot pepper rankings, that’s barely a blip on the radar.
Another pepper that’s become synonymous with Mexican cooking, these chilis are essentially jalapeños that have been dried and smoked – and many of them are stored in delicious adobo sauce.
Still, the treatment must do something to the capsaicin delivery system, as the prepared version of the pepper ranks lower on the Scoville Scale than its fresher form.
Perhaps the most well-known type of chili pepper, these classic green examples aren’t even middle-ground when it comes to relative heat.
Do with that information what you will the next time one of your friends wants to order nachos without the jalapeños on top.
Serranos are sometimes confused with their jalapeño counterparts, resembling the pepper in color and shape.
Serranos are typically smaller than jalapeños, however – but don’t let their size fool you. They rank a full 13,000 Scoville Heat Units higher on the scale than their Mexican cousins.
You’ve most likely heard of the hot sauce these peppers are used to produce. And you may even have some memories of cartoon characters trying a bit on their tongue, before steam starts shooting out of their ears.
The reaction may not be that far off in real life, with the peppers counting an impressive 125,000 SHU to their name, meaning their testers had to try 1,250 diluted versions of the formula before they could no longer detect the pepper’s heat.
Now we’re starting to get seriously spicy: Habaneros are so hot they usually come with their own heat warnings.
The scrunched-up plants may look like midgets of the pepper world but their capsaician powers are mighty indeed.
Scotch Bonnets are a relative newcomer in the Scoville field, originating in the Caribbean and West Africa.
The peppers are used to make some of the area’s notoriously spicy concoctions – and best eaten with caution, with the team of experts needing 3,500 doses of diluted pepper formula before they could finally be free of the Scotch Bonnet’s heat.
These India natives are typically the true test of a pepper apostle, with most heat lovers considering them the ultimate hot pepper prize.
They’re also noteworthy for being the first type of chili to breech 1 million on the Scoville Scale – making them an incredibly difficult thing to stomach, even in tiny doses. (A full glass of milk and a carload of willpower is advised before experimenting with any ghost pepper products.)
And then there was one.
The Carolina Reaper has the profound distinction of being the hottest pepper to date ranked on the Scoville Scale, with a mind-boggling SHU count of 2.2 million. That means the poor tasters of these peppers had to endure 22,000 rounds of testing before the heat of this powerful plant was finally off their pallets.If you ask us, the Blue Oyster Cult was wrong: Maybe we all should fear the reaper, after all.