The Scoville scale is a measure of the hotness or piquancy of a chilli pepper. These fruits of the Capsicum genus contain capsaicin, a chemical compound which stimulates chemoreceptor nerve endings in the skin, especially the mucous membranes. The number of Scoville heat units (SHU) indicates the amount of capsaicin present.

The scale is named after its creator, American chemist Wilbur Scoville, who developed a test for rating the pungency of chili peppers. His method, which he devised in 1912, is known as the Scoville Organoleptic Test.

In Scoville’s method, a solution of the pepper extract is diluted in sugar syrup until the “heat” is no longer detectable to a panel of (usually five) tasters; the degree of dilution gives its measure on the Scoville scale. Thus a sweet pepper or a bell pepper, containing no capsaicin at all, has a Scoville rating of zero, meaning no heat detectable, even undiluted. Conversely, the hottest chillies, such as habaneros, have a rating of 200,000 or more, indicating that their extract has to be diluted 200,000-fold before the capsaicin present is undetectable.

Scoville Rating

     

Type of Chilli Pepper

15,000,000-16,000,000
Pure Capsaicin
9,000,000-9,100,000
Nordihydrocapsaicin
2,000,000-5,300,000
Standard US Grade Pepper Spray
855,000-1,041,427
Naga Jolokia
876,000-970,000
Dorset Naga
350,000-577,000
Red Savina Habanero, Chocolate Habanero
100,000-350,000
Habanero, Scotch Bonnet, Rocoto
100,000-350,000
Scotch Bonnet
100,000-200,000
Jamaican Hot
50,000-100,000
Thai, Malagueta, Tepin (Chiltepin)
30,000-50,000
Cayenne, Aji, Tabasco, Numex Twiliight
10,000-23,000
Serrano
7,000-8,000
Tabasco Sauce (Habanero)
5,000-10,000
Wax
2,500-5,000
Jalapeno
2,500-5,000
Tabasco Sauce (Tabasco Pepper)
1,500-2,500
Rocotillo
1,000-1,500
Poblano
600-800
Tabasco Sauce (Green Pepper)
500-1000
Anaheim
100-500
Pimento, Pepperoncini
0
Bell Pepper, No Heat