With National Science Foundation support, Dr. Patricia Crown and Dr. Jeffrey Hurst will characterize the temporal and spatial extent of cacao (chocolate) use and the nature of cacao exchange networks in the American Southwest. Recent research revealed the presence of cacao residues in ceramics from refuse deposits at Pueblo Bonito, Chaco Canyon, New Mexico, dated to A.D. 1000-1125. This finding demonstrates the presence of cacao, a tropical product, in the American Southwest. However, knowledge of cacao use in this region is limited by the fact that only five sherds from one site have been analyzed, with cacao recovered from three of those. Cacao may have been widely traded beyond Pueblo Bonito, particularly in conjunction with the exchange in Scarlet Macaws, another tropical species known to be widely present in the Southwest from A.D. Cacao may have been present earlier and later than the Pueblo Bonito materials.
To determine the extent of cacao use and the nature of cacao exchange networks in the American Southwest, pottery from other sites and other time periods will be tested for cacao residues. To understand how cacao was consumed, testing will also be completed for additives traditionally used in Mesoamerican cacao drinks, such as honey. Decisions about which areas to test will follow three assumptions. First, to get to Chaco, exchange from Mesoamerica likely followed routes either through southwestern New Mexico, southern Arizona, or up the Rio Grande. Second, exchange in cacao likely accompanied exchange in macaws, because these biological species came from the same tropical environments, so pottery from sites with macaws will be given priority in sampling. Finally, because cacao consumption elsewhere in the New World always involved special vessel shapes, testing will focus on special vessel forms that likely functioned as drinking vessels for each area.
High Performance Liquid Chromatography-Mass Spectrometry will be used to test for the presence of theobromine, a biomarker for Theobroma cacao in the paste of the pottery. For samples with evidence for theobromine, additional testing will be conducted to identify any other components of the cacao beverage. The analysis will be conducted at the Core Facility, MS Hershey Medical Center, Hershey, Pennsylvania.
The intellectual merit of the research includes assessing the prehispanic distribution of cacao in the American Southwest, furthering knowledge of exchange relationships between the Southwest and Mesoamerica, and evaluating how widespread cacao use might have been in ritual activities in the Southwest.
The research will create interdisciplinary interaction between the University of New Mexico, the Hershey Center for Health and Nutrition, the MS Hershey Medical Center, and several museums contributing sherds to this research. The results will be widely disseminated in the popular press and scholarly publications. Previous research on this topic received extensive media attention.
With NSF funding, Patricia Crown and Jeffrey Hurst examined when and where populations in the American Southwest prepared and consumed chocolate drinks before European Contact. They analyzed almost 200 broken pieces of pottery from an area stretching from northern Chihuahua to southern Colorado, and dating between about A.D. 500-1450. They burred off the outer surface of the pottery to remove contaminants, and then ground the inner portion to powder. They analyzed the powdered pottery with a technique called High Performance Liquid Chromatography/Mass Spectrometry, which identifies residues absorbed into the pottery fabric. The samples were analyzed at the W.M. Keck Center for Instrumental and Biochemical Comparative Archaeology at Millsaps College in Jackson, MS, under the direction of Dr. Timothy Ward. In addition to identifying chocolate, the PIs developed a method for identifying Ilex, or Holly, residues. Holly also has high caffeine content and this research showed the Native Americans in what is now the St Louis area drank Ilex in the past. The intellectual merit of the project included demonstrating the long-standing exchange relationships between the American Southwest and Mesoamerica. Populations in North America exchanged caffeine-rich foods over long distances, probably largely for ritual consumption and as luxury foods consumed only on special occasions. Broader impacts of this research included training both undergraduate and graduate students in methods of organic residue analysis at the University of New Mexico and at Millsaps College. The PIs gave over 30 public talks to hundreds of people about this research. Extensive media attention included national and international articles, television reporting, and radio interviews detailing the project results. An ice cream flavor, restaurant menus, and chocolatiers have capitalized on public interest in this project with new products and names (Chaco Canyon Chocolate).
