West African cuisine is known for its distinct ingredients and flavors, often enhanced by the addition of a large and diverse range of plant foods. But how long have people in this region been eating these plants, and where did they come from?
A new study by a team of scientists from the University of Bristol and Goethe University has uncovered the first insights into the origins of West African plant-based cuisine, locked inside pottery fragments dating back some 3,500 years ago.
The researchers analyzed more than 450 prehistoric pots from the Central Nigerian Nok culture, which is famous for its large-scale terracotta figurines and early iron production in West Africa. The pots contained traces of lipids, or fats, oils and waxes, that provide a biomolecular fingerprint of the foods that were cooked in them.
“What we found in the Nok pottery was chemical evidence of a remarkable range of plants. It is impossible to say how many but this suggested that—like today—a wide variety of leafy greens were processed together with cereals, pulses and what were probably yams,” said Dr. Julie Dunne, from the University of Bristol’s Organic Geochemistry Unit, who led the research.
The plant lipid profiles extracted from the Nok pots are the most varied and complex seen globally in archaeological pottery to date, suggesting a diverse and nutritious diet that included many indigenous West African crops.
Some of these crops are still eaten today, such as cowpea, pearl millet, African eggplant, okra and baobab leaves. Others are less familiar, such as jute mallow, bombax and bitter leaf.
The study also provides clues about the possible origins of culinary yams, which are a staple food in many West African dishes. Some of the lipid profiles found on the pots could indicate underground storage of yams or other edible tubers.
“Charred plant remains like seeds and nutshells preserved in the archaeological sediments reflect only one part of what people consumed in the past,” said Professor Katharina Neumann from Goethe University, who directed archaeobotanical research on the Nok Project. “We hoped that chemical analyses would provide additional insights into food preparation.”
The researchers used a combination of lipid biomarker and stable isotope analyses to identify the types of plants that were cooked in the pots. They also compared their results with modern reference samples from West Africa.
“Investigating the origin and development of indigenous West African crops has global relevance, providing information on human adaptation and plant history,” said Dr. Dunne.
The study, published in the journal Archaeological and Anthropological Sciences, sheds new light on the history of plant domestication and food preparation in West Africa, as well as the cultural and environmental factors that shaped it.
The study also demonstrates the power of organic residue analysis for studying ancient diets, especially when other sources of evidence are scarce or degraded.
“Some food plants, including grain and legume crops, have been found on archaeological sites in West Africa dating as far back as 3,000 years ago. Finding evidence for vegetables and leafy greens is difficult, however, as they do not generally survive over archaeological timescales,” said Mackenzie Myers Fowler, a science writer who reported on the study for Science Connected Magazine.
The researchers hope that their findings will inspire more studies on ancient pottery and plant foods in West Africa and beyond. They also hope that their work will raise awareness and appreciation for the rich and diverse culinary heritage of this region.
– Chemical traces in ancient West African pots show a diet rich in plants, The Conversation, April 18, 2022
– Tracing the origins of plants in West African cuisine, Phys.org, January 17, 2022
– Nok Culture Pottery Adds Clues to Ancient Diets, Science Connected Magazine, February 1, 2022
– Chemical traces in ancient West African pots show a diet rich in plants, Phys.org, April 18, 2022