A farmer cuts ripe cocoa pods off a tree

A farmer harvests cacao — the source of chocolate — in northeastern South America. New clues show that cacao products have a long history in the region. Credit: Thomas Cristofoletti/Planet Pix/ZUMA

Agriculture

Humans indulged a taste for chocolate a millennium earlier than realized

Evidence from ancient bottles and other objects indicates that South Americans were eating cacao products around 3300 bc.

People in South America were consuming products of the cacao tree — the source of chocolate — more than 5,000 years ago, according to analysis of prehistoric artefacts.

Researchers have long known that cocoa was a ritual drink for the people of pre-Columbian Mexico. Until now, the oldest archaeological evidence for cacao (Theobroma cacao L.) dated to 3,900 years ago and came from a Central American site, although genomic analysis suggested that the tree’s place of origin lay further south, along the Amazon River.

Michael Blake at the University of British Columbia in Vancouver, Canada, and his colleagues analysed residues on bottles and other items from the Santa Ana-La Florida archaeological site in the South American nation of Ecuador. These residues contained cacao DNA, grains of cacao starch and theobromine, a stimulant found in cacao beans.

Results from this analysis indicate that the site’s people, who were part of the Mayo-Chinchipe culture, consumed cacao 5,300 years ago — more than 1,000 years before the next-earliest evidence. The Mayo-Chinchipe people might have consumed cacao as a beverage, a food, a medicine or a stimulant, the authors say.