The Science of Chili

Forrest M. Mims III

As spring approaches and trees leaf out, I keep a watchful eye on our wild chili plants. Last fall they were covered with bright red berries, which birds long ago consumed. Did those leafless plants survive the winter freezes? We should know soon.

Botanists call these attractive perennials Capsicum annuum. Common names include chili pequin, chile piquin, chile del monte, chiltepin, chiltecpin, mosquito chili, and bird chili (or chile de pájaro). Under the name chiltepin, they are the native pepper of Texas.

Chili pequins can be found growing wild across Mexico and the U.S. Southwest. On our place they grow by fences or near the trunks of large mesquites and cedar elms.

Pequins are the hottest chili I’ve ever tasted. Many sources claim that habaneros are hotter, and I’ll take their word on that.

More than 500 years ago Christopher Columbus brought chili peppers from the New World back to Spain. Soon chili circled the world.

Figure 1. Chili pequins have been used as a food for more than 6,000 years. Photograph by Forrest M. Mims III.

Within a few centuries chili became as important a part of the diet for some cultures in Europe, Africa and Asia as it had long been in the Americas.

The rapid spread of chili around the world is well documented. But when did chili originate in the New World? Are those chili pequins we find in South Texas native plants?

Tracing the origin of chili has proved difficult due to the lack of clues. Seeds and pollen from ancient chili have been hard to find. Now Linda Perry, a Smithsonian scientist, has found new clues.

Dr. Perry is looking for answers about pre-Columbian chili and other American food crops. She’s with the Archaeobiology Program in the Department of Anthropology at the Smithsonian National Museum of Natural History. She’s well qualified, for she has degrees in biology, botany and anthropology.

Some fascinating results of chili research by Perry and scientists from Canada, Panama, Venezuela and the U.S. were recently published in Science, the world’s leading scientific journal.

Perry and her collaborators discovered that evidence of chili has been present all along at archaeological sites. The evidence is in the form of microscopic starch grains about the size of typical pollen grains. The starch grains have a characteristic appearance that allowed the scientists to find them still attached to milling stones and cooking bowls as old as 6,100 years!

Perry’s group found chili pequin grains in archaeological sites in Mexico’s Tehuacan Valley dated as old as 6,000 years. In every site the chili grains were associated with maize, which suggests that nachos and salsa go back a very long way.

For the latest on chili pequin and other peppers, visit www.world-pepper.org and click on “Proceedings of the 16th International Pepper Conference.” This is where I found the list of common names for our Capsicum annum at the beginning of this column.

"World of Science" columns are selected and sometimes revised from columns published in the San Antonio Express-News or the Seguin Gazette-Enterprise. The columns are intended for a general audience. Forrest M. Mims III and his science are featured online at www.forrestmims.org and www.sunandsky.org .