How spicy something is is pretty subjective. We all know that one person who thinks black pepper is too spicy, while on the other end we have that friend who eats Carolina Reapers for fun. Everyone’s palate is different, as is their tolerance for heat. Fortunately, we don’t have to guess how spicy something is because there is a way to scientifically measure spiciness, and it’s called the Scoville Scale.
Basically, the Scoville scale measures the “...the pungency (spiciness or "heat") of chili peppers, as recorded in Scoville heat units (SHU), based on the concentration of capsaicinoids, among which capsaicin is the predominant component.” (https://en.wikipedia.org/wiki/Scoville_scale).
In other words, we can understand just how many SHU a pepper or hot sauce may have, and not just take the word of your friend Jake, who thinks everyone on Hot Ones is a sissy.
We’ve pulled together a list of the estimated Scoville Heat Units of some common peppers that you’ll find in hot sauces and recipes. But there are a few things to keep in mind:
1 ) Just because a hot sauce has a specific pepper that may be super, ridiculously hot, doesn’t mean that the hot sauce has the same SHU. You’ll often see hot sauces proclaiming “Made with 1.5M SHU Peppers!” or something similar, and it can be a bit misleading. Sure, the pepper that goes into the sauce may rate that high, but the sauce probably isn’t just straight pepper. It probably has vinegar, water, and other ingredients that will dilute the heat. And that’s assuming that the pepper was really that hot to begin with!
A lot of sauce makers don’t go through the expense of having their sauces lab tested for SHU. Instead, they’ll use a “best guess” based on the percentage of pepper used in the sauce. And then put marketing spin on it to make it sound hotter than it probably is. Also, when SHU is determined, they have to dry the sauce. So again, that sauce with all of the “wet” ingredients, may not be as concentrated as the dry product that was tested.
2 ) The heat from peppers will vary wildly depending on a number of factors, including where they were grown, soil, sunlight, rain, ripeness, etc., etc. Much like any other fruit or vegetable, the flavor, sugars, and in this case heat, will all be impacted by growing conditions. That’s why you might have one jalapeño that’s not much spicier than a bell pepper, and another one that will make your eyes water.