Education
What is Scoville?
The Scoville scale is a measurement of the pungency (spiciness or "heat") of chili peppers and other spicy foods, recorded in Scoville Heat Units (SHU).
The History
In 1912, American pharmacist Wilbur Scoville developed a method for measuring the "heat" of various chili peppers. Originally called the Scoville Organoleptic Test, it involved diluting an extract of the pepper in sugar water until the "heat" was no longer detectable by a panel of human tasters.
The degree of dilution gave the pepper its SHU rating. For example, a pepper with 2,500 SHU required 2,500 parts sugar water to one part pepper extract to neutralize the heat.
How it's measured today
While the original test relied on human taste buds (which can be subjective and prone to "palate fatigue"), modern testing uses High-Performance Liquid Chromatography (HPLC).
HPLC measures the actual concentration of capsaicinoids in a pepper. These results are then converted back into Scoville Heat Units to maintain the familiar scale we use today.
What is Capsaicin?
Capsaicin is the active component of chili peppers that produces the burning sensation. It's an irritant for mammals, including humans, and produces a sensation of burning in any tissue with which it comes into contact.
Interestingly, birds are immune to capsaicin, allowing them to eat peppers and spread the seeds without the burning sensation!
Reference Benchmarks
To give you an idea of where common items sit on the scale:
Scoville FAQ
Common questions about SHU, heat ratings, and how to interpret the scale.
What does SHU stand for?
SHU stands for Scoville Heat Units. It is the standard way of describing how spicy a pepper or pepper product is on the Scoville scale.
Does a higher Scoville rating always mean a pepper tastes better?
No. A higher SHU means more heat, not better flavor. Many peppers are valued for sweetness, fruitiness, smokiness, or aroma as much as for their spice level.
Why do some peppers have a Scoville range instead of one number?
Pepper heat changes with variety, ripeness, growing conditions, and testing method. A range shows the heat a pepper is commonly reported to reach rather than implying every pod has the exact same SHU.
Are hot sauces and powders measured in Scoville units too?
Yes. The Scoville scale is also used for pepper products like sauces, powders, and extracts. Their ratings depend on how concentrated the capsaicinoids are in the finished product.
What is the hottest possible Scoville rating?
Pure capsaicin is commonly cited at 16,000,000 SHU, which is the practical top end of the familiar Scoville scale. Real peppers fall far below that number.