Understanding Heat Levels: The Scoville Scale Explained
The Scoville Scale Explained
The Scoville scale measures capsaicin concentration in chillies. Named after pharmacist Wilbur Scoville who devised the original test in 1912, it's the standard measure of chilli heat worldwide.
How it works
Original method: a panel of tasters evaluated diluted chilli extracts until heat was no longer detectable. The dilution factor = Scoville Heat Units (SHU).
Modern method: High-Performance Liquid Chromatography (HPLC) directly measures capsaicin and dihydrocapsaicin concentration. More accurate, less dependent on human tasters.
The scale in practice
| Variety | SHU range |
|---|---|
| Bell pepper | 0 |
| Pepperoncini | 100–500 |
| Jalapeño | 2,500–8,000 |
| Serrano | 10,000–25,000 |
| Cayenne | 30,000–50,000 |
| Bird's eye / peri-peri | 50,000–100,000 |
| Habanero | 100,000–350,000 |
| Scotch bonnet | 100,000–400,000 |
| Ghost pepper (bhut jolokia) | 855,000–1,041,427 |
| Carolina Reaper | 1,400,000–2,200,000 |
| Pepper X | ~2,693,000 |
What the numbers mean
1,000 SHU is barely noticeable to most people. At 50,000 SHU (cayenne territory), most people feel clear heat. Beyond 200,000 SHU, most untrained palates are seriously challenged. Above 1,000,000 SHU, you're in extreme territory that requires deliberate tolerance.
SHU is not the whole story
Heat quality matters as much as quantity. A bird's eye at 75,000 SHU hits fast and fades quickly. A habanero at 150,000 SHU builds slowly, lingers, and has fruity overtones. A Reaper hits fast and lasts 20+ minutes.
Always consider flavour alongside heat.
