Nixtamalization at La Corona: Microbotanical analysis of ceramic vessels indicates Late Classic Maya cooking techniques

Maize (Zea mays) was a fundamental part of the diet for the Classic period Maya (ca. 250–900 CE) and other Mesoamerican societies. Nixtamalization, the process whereby maize is cooked in an alkaline solution, is important as it enhances the nutritional value of maize, among other reasons. However, documenting this process in the archaeological record is not straightforward. A microbotanical study of residues collected from ceramic vessels and grinding stones from Late Classic (ca. 600–900 CE) contexts at the Lowland Maya site of La Corona (Peten, Guatemala), revealed the presence of starch spherulites. Their authenticity was confirmed by polarized microscopy and Scanning Electron Microscope (SEM) imaging combined with iodine staining. We argue that nixtamalization as a cooking technique was occurring at La Corona during the 7th and 8th centuries CE. We present evidence from ceremonial contexts, specifically burial and feasting/commensal events. This is the earliest evidence of lime-treated maize in the Maya area recovered directly from ceramic vessels linked to preparation and/or consumption of food.