New Chemical Analyses Take Confirmation Back 500 Years and Reveal that the Impetus for Cacao Cultivation was an Alcoholic Beverage
13 NOVEMBER 2007, PHILADELPHIA, PA—–The earliest known use of cacao––the source of our modern day chocolate––has been pushed back more than 500 years, to somewhere between 1400 and 1100 B.C.E., thanks to new chemical analyses of residues extracted from pottery excavated at an archaeological site at Puerto Escondido in Honduras. The new evidence also indicates that, long before the flavor of the cacao seed (or bean) became popular, it was the sweet pulp of the chocolate fruit, used in making a fermented (5% alcohol) beverage, which first drew attention to the plant in the Americas.
That cacao’s popularity on the world stage began with its role in an alcoholic beverage does not surprise archaeochemist Dr. Patrick McGovern, Senior Research Scientist at the University of Pennsylvania Museum of Archaeology and Anthropology and one of five authors of the scientific research article on the discovery (“Chemical and archaeological evidence for the earliest cacao beverages,” by John S. Henderson, Rosemary A. Joyce, Gretchen R. Hall, W. Jeffrey Hurst, and Patrick E. McGovern) to be published on-line in Early Edition the week of November 12th http://www.pnas.org/ and in the 27 November 2007 print issue of PNAS USA (pp. 18937-18940, Issue 48, Volume 104).
“This development probably provided the impetus to domesticate the chocolate tree and only later, to prepare a beverage based on the more bitter beans,” suggested Dr. McGovern. “An alcoholic beverage from the pulp, carrying on this ancient tradition, continues to be made in parts of Latin America.”
The famous chocolate beverage of the Mayan and Aztec kings, served at special ceremonies and feasts, came later. It was made from the cacao beans, often mixed with chillis, special herbs, honey, and flowers. The liquid was frothed into a foam, and both inhaled and drunk.
Throughout his career, Dr. McGovern has worked on techniques to determine what food and, more often, drink, once filled the ancient pottery and other food vessels that archaeologists find throughout the world—shedding new light on the gastronomic and cultural story of human civilization around the world. Time and again, he has seen that alcoholic beverages go hand in hand with the earliest development of human cultures. As with the cacao fruit in Central America, high-sugar fruits and honey were similarly used to produce alcoholic beverages in other parts of the world at an early date, including Neolithic China and the Near East, two regions where Dr. McGovern has played a role in the discovery of the earliest known beverages (see Ancient Wine, Princeton University Press, 2003/2006, and “Fermented Beverages of Pre- and Proto-Historic China,” Proceedings of the National Academy of Sciences USA 101.51: 17593-98).
“The beverages of China and the Near East also became the prerogative of the elite, and were incorporated into religious ceremonies and celebrations,” he noted. “They were often of considerable economic value, just as the cacao bean was the medium of exchange in the Aztec empire, and they were traded, given in tribute, and offered as gifts to fellow rulers and the gods.”
Though not part of the archaeological research team at Puerto Escondido in Honduras, Dr. McGovern got involved in the scientific research on this material after he read an article in the Fall 2001 issue of the Arts & Sciences Newsletter of his alma mater, Cornell University. Entitled “The Birth of Chocolate or, The Tree of the Food of the Gods,” it was written by Cornell Anthropology Professor John S. Henderson, co-excavator, with University of California Berkeley Professor Rosemary A. Joyce, at the Honduras site. Dr. Henderson had graduated in 1967, a year after McGovern, yet their paths had never crossed.
Dr. McGovern read in the article that Dr. Henderson was looking for a way to extract the ancient residues of a liquid from the pores of the vessels.
“I sent an email to John, suggesting that our Penn Museum laboratory, where I work with Gretchen Hall, Research Associate, probably had the tools available to find out what the ancient vessels held. From there, he negotiated to have a collection of sherds from vessels of types believed to have held liquid, and the Penn Museum and Hershey Foods Technical Center labs carried out extractions and analyses.”
“The results were astounding–-every vessel that he had chosen and was tested gave a positive signal for theobromine, the fingerprint compound for cacao in Central America.”
Photo: Bottle from an unidentified site in northern Honduras corresponding to a type produced between 1400 and 1100 BC at Puerto Escondido. Barraca Brown Burnished type (Ocotillo phase, 1100-900 BC). Collection of the Instituto Hondureño de Antropología e Historia, Museo de San Pedro Sula, Honduras. Drawing courtesy of Yolanda Tovar.
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