Chilies originate in South America and have been eaten for at least 9,500 years. Organised cultivation began around 5,400 BC. Christopher Columbus was the first European to encounter chilies, when he landed on the island of Hispaniola in 1492. He thought it was a type of pepper and called it the “red pepper”, a name still used today. After their introduction to Europe they were an immediate sensation and were quickly incorporated into the diet. From there they spread to Africa, India and East Asia.
The reason for the chili’s “hotness” lies in a chemical called Capsaisin. Capsaisin causes temporary irritation to the trigeminal cells, which are the pain receptors in the mouth, nose and throat. After the pain messages are transmitted to the brain, endorphins, natural pain killers, are released and these not only kill the pain but give the chili eater a short lived natural high. Other side effects include: an increased heart rate, a running nose and increased salivation and sweating, which can have a cooling effect in hot climates.
The reason for the presence of Capsaisin is thought to be to deter animals from eating the fruit. Only mammals feel the burning effects; birds feel nothing. As birds are a better method of distributing the seeds, which pass intact through their guts, Capsaisin would seem to be a result of natural selection.
The smaller chilies tend to be the hottest. This may reflect the fact that they tend to grow closer to the ground and are therefore more vulnerable to animals. The heat of a chili is measured on the Scoville scale. The hottest types such as the Habenero and the Scotch Bonnet rate between 100,000 and 300,000, the world famous Tabasco sauce rates at 15,000 to 30,000, about the same as the Thai prik khee nu, while the popular Jalapeno is between 5,000 and 15,000. Powdered chili is 500 to 1,000 and the mild capsicins and paprikas can range between 100 and 0.