Ethnographic fieldwork in recent decades has vastly expanded our knowledge of the dizzyingly varied forms of Mesoamerican cacao beverages. At last year’s conference workshop on Mexican condiments, Richard Tan and Maite Lascurain presented a range of flowers including Bourreria huanita and the famous ear-flower Cymbopetalum penduliflorum added to traditional cacao beverages for specific aromas or flavors. This year we focus on diverse cacao foaming agents, i.e. saponin- or latex-rich plant additives from species of Smilax, Gonolobus, Marsdenia, that contribute apparently nothing in olfactory or gustatory terms, but which when frothed, bind with specific surfactants in cacao to create a stable colloidal suspension. The result ranges from a rich head of bubbles to a bowl of pure foam, a luxurious, ethereal comestible, light and insubstantial as air. Physico-chemical properties and mechanisms of these foams are inadequately understood and there is a confusing diversity of recipes and practices. Mazatec, Chinantec, Zapotec and other Mesoamerican names might have Proto-Mixe-Zoque origins; but they also resonate with one lexeme in Nahuatl “popo'' which refers to blurring, bubbling, aeration, smoke and other amorphous states. Otherwise, these foams don’t seem to be classified as a group nor encoded in any other indigenous cognitive or lexical categories. This puts stumbling blocks in efforts to construct an overarching ethnobotanical theory to explain these items, which are unique and without equivalent among world food cultures.
This workshop is designed as a series of experiments to puzzle out the mysteries of the human knowledge and human knowhow involving plants that cause foam. We review 16th century references to different cacao beverages in the Florentine Codex or as described by Dr. Francisco Hernandez. We establish the ethnography and geography of these foamed drinks in diverse living indigenous cultures. We conduct hands-on demonstrations of historically-attested methods for producing foam, including pouring from a height, to see if they really work. We explain the step-by-step process of recreating the celebrated bu’pu of the Isthmus of Tehuantepec, which is flavored and foamed with Plumeria rubra flowers, and taste our work afterwards. Depending on ingredient availability, we also hope to deconstruct one complex cacao beverage, perhaps the tejate of Oaxaca, foaming each component of the recipe, including pixtle (Pouteria sapota), the flowers of Quararibea funebris, the processed seeds of pataxte (Theobroma bicolor), individually and then together, to try to understand the biotechnology involved, and explain what happens and why. Come formulate your own wild theories and join in the speculative fun!