Mayas may have used chocolate as spice

London - Archaeologists say they have found traces of 2,500-year-old chocolate on a plate in the Yucatan peninsula, the first time they have found ancient chocolate residue on a plate rather than a cup, suggesting it may have been used as a condiment or sauce with solid food.

The discovery announced this week by Mexico's National Institute of Anthropology and History expands the envelope of how chocolate may have been used in ancient Mexico.

It would also suggest that there may be ancient roots for traditional dishes eaten in today's Mexico, such as mole, the chocolate-based sauce often served with meats.

"This indicates that the pre-Hispanic Maya may have eaten foods with cacao sauce, similar to mole," the anthropology institute said.

The traces of chemical substances considered "markers" for chocolate were found on fragments of plates uncovered at the Paso del Macho archaeological site in Yucatan in 2001.

The fragments were later subjected to tests with the help of experts at Millsaps College in Jackson, Mississippi, as part of a joint project.

The tests revealed a "ratio of theobromine and caffeine compounds that provide a strong indicator of cacao usage", according to a statement by the university.

"This is the first time it has been found on a plate used for serving food," the Daily Express quoted archaeologist Tomas Gallareta as saying.

"It is unlikely that it was ground there (on the plate), because for that they probably used metates (grinding stones),” he added.