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The Real Heat Behind Hot Peppers
COLUMBIA, SC, USASaturday, July 18, 2026
Peppers don’t taste spicy in the way we think; they actually trigger a burning feeling thanks to a compound called capsaicin. Capsaicin attaches itself to special receptors in the mouth that normally sense heat, sending signals to the brain and making us feel a fiery sensation.
Where the Heat Lurks
- The hottest part of a pepper isn’t where most people look.
It’s the thin white layer, called the pith, that surrounds the seeds. - This membrane packs the most capsaicin, which is why slicing a pepper from top to bottom can feel much hotter than cutting it in half.
Measuring Pepper Heat
In 1912, Wilbur Scoville created a scale that ranks peppers by their capsaicin content.
| Pepper | Scoville Units (approx.) |
|---|---|
| Bell pepper | 0 |
| Dried poblano | 1 000 – 2 000 |
| Jalapeño | ~5 000 |
| Cayenne | ~50 000 |
| Habanero | ~150 000 |
| Ghost pepper | >300 000 |
| Carolina Reaper (current record) | 1.5 million |
The Scoville scale measures the heat by diluting pepper extracts until the taste no longer registers as spicy. The higher the number, the more capsaicin is present.
Takeaway
- The pith holds most of the heat.
- Scoville units give a standardized way to compare pepper intensity.
- The Carolina Reaper stands out as the hottest pepper known, reaching a staggering 1.5 million units.
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