Why some like it hot: The science of spiciness

Why some like it hot: The science of spiciness

The research on chilli peppers and spiciness represents an outstanding example of multidisciplinary science. Several researchers in the last decades have provided information and curiosities about this most unique and desirable oral sensation. Spiciness, or its perception, occurs in most cuisines worldwide. The chilli pepper of the genus Capsicum (family Solanaceae) is one of the world’s most widely used spices, found in thousands of recipes and sometimes eaten as a stand-alone dish. One in every four people on the planet currently eats chillies on a daily basis. As a forest eco-physiologist, I study the adaptation traits developed by plantorganisms to interact with other living beings and the surrounding environment. The research on chilli peppers and spiciness represents an outstanding example of multidisciplinary science. Several researchers in the last decades have provided information and curiosities about this most unique and desirable oral sensation. Chilli peppers were unknown to much of the world until Christopher Columbus made his way to the New World in 1492. Several origin theories flagged different parts of South America as “the” spot where chillies came from. A phylogenetic analysis found that they are native to an area along the Andes of western to northwestern South America. These ancestral wild Capsicum were “small red, round, berry-like fruits.” The earliest evidence of domestication dates back to 6,000 years ago in Mexico or northern Central America. Chilli peppers were introduced into Europe in the 16th century. Currently, there are five domesticated chilli peppers species. The five domesticated species are Capsicum annuum, C. chinense, C. frutescens, C. baccatum and C. pubescens. The species with the most varieties is the C. annuum, which includes the New Mexican jalapeno and the bell pepper. The Habaneros and scotch bonnets instead belong to the C. chinense, while Tabasco peppers are C. frutescens. The South American ajis are C. baccatum, while the Peruvian rocoto and the Mexican Manzano are C. pubescens. Nowadays, more than three million tons of chilli peppers are produced yearly for a global market that is well over USD 4 billion.