The substance in chiles that makes them hot is called capsicum. It
is concentrated in the veins of the fruit (not the seeds)and stimulates
the nerve endings in your mouth, fooling your brain into thinking you're
in pain. The brain responds by releasing substances called endorphins,
which are similar in structure tomorphine. A mild euphoria results,
and chiles can be mildly addictive because of this hot pepper "high".
Chile hotness is rated in Scoville units The hottest pepper on record is the habanero/Scotch bonnet which some claim are the same pepper and others claim are slightly different varieties. Habaneros are rated at 100,000 to 350,000 Scoville units By contrast, the lowly serrano comes in at about 5,000 to 15,000 Scoville units.
Scoville Units are the measurement of capsicum level (the oil that makes chiles hot). Although chiles can vary from pod to pod and plant to plant, listed below is an approximate scale for several varieties of chiles.
Scoville Units |
Chile Varieties |
| 100,000-500,000 | Habanero, Scotch Bonnet, South American chinenses, African birdseye |
| 50,000-99,999 | Santaka, Chiltepin, Rocoto, Chinese kwangsi |
| 30,000-49,999 | Piquin, Cayenne Long, Tabasco, Thai prik khee nu, Pakistan dundicut |
| 15,000-29,999 | de Arbol; crushed red pepper; habanero hot sauce |
| 5,000-14,999 | Early Jalapeño, Aj Amarillo, Serrano; Tabasco ® Sauce |
| 2,500-,4,999 | TAM Mild Jalapeño, Mirasol; Cayenne Large Red Thick; Louisiana hot sauce |
| 1,500-2,499 | Sandia, Cascabel, Yellow Wax Hot |
| 1000-1,499 | Ancho, Pasilla, Española Improved; Old Bay Seasoning |
| 500-999 | NuMex Big Jim, NuMex 6-4, chili powder |
| 100-500 | R-Naky, Mexi-Bell, Cherry; canned green chiles, Hungarian hot paprika |
| 10-99 | Pickled pepperoncini |
| 0 | Mild Bells, Pimiento, Sweet Banana, U.S. paprika |