Chocolate residue found on early Maya plates, a first

Archaeologists have found residues of cacao -- or chocolate -- on 2,500-year-old plate fragments from the Northern Maya Lowlands in Yucatan, Mexico. Although cacao residue has been found in cups from other sites that are 1,000 years older, this is the oldest trace of cacao in this northern region.

Perhaps more important, it is the first evidence that the Maya used cacao for anything other than as a drink. The presence of cacao on a plate suggests that it was used as a spice or sauce for food. Perhaps it was even a precursor of the popular mole sauce for meats, often made with chocolate, now widely used in Mexican cuisine.

Researchers had previously thought that the only uses for cacao by the Maya were crushing the beans and dissolving it in liquid to make a drink something like hot chocolate, or fermenting the pulp that surrounds the beans in its pod to make an alcoholic drink.

The plate fragments were recovered in 2001 by archaeologist Tomas Gallareta Negron of Mexico’s National Institute of Anthropology and History and his colleagues at Paso del Macho in the Southern Puuc region of Mexico. Paso del Macho, which dates from 600 BC to 500 BC, was a relatively small site, but must have been important because it had several small mounds and a ball court, said archaeologist George Bey of Millsaps College in Jackson, Miss., who also worked at the site. “The fact that the inhabitants were able to acquire and use cacao indicates they were part of the larger Maya world even at this early date,” he said in a news release announcing the discovery.


Chemist Timothy Ward of Millsaps and his colleagues extracted the residue from the plate fragments and submitted it to mass spectrometry, which identified a ratio of theobromine and caffeine characteristic of cacao.

“This evidence, combined with other archaeological, architectural and settlement data, is providing us with a new view of this little known area of the Maya world during the earliest times,” Gallareta Negron said. “The Northern Maya world was just as complex and sophisticated as the far better known Southern Maya area, and we can now add the consumption of cacao to this list of traits.”