International Research Team including Scientists at Freie Universität Berlin Analyzes Protein Residues in 8000-year-old Ceramic Vessels
No 257/2018 from Oct 03, 2018
Through an analysis of ceramic vessels, an international research team has gained insights into the dietary habits of inhabitants of a prehistoric settlement. They identified protein residues from cereals, legumes, dairy products, and meat in the almost 8,000-year-old vessels from the village of Çatalhöyük in Turkey. They were able to assign some proteins to specific plant and animal species. Researchers from the Max Planck Institute for the Science of Human History in Jena, Freie Universität Berlin, and the University of York (U.K.) participated in the project.
The scientists analyzed shards from the West Mound in Çatalhöyük, which was inhabited from about 7100 BC until 5600 BC. The pottery shards date back to around 5900 BC to 5800 BC, near the end of the colonization period. They originate mainly from open shells and have calcified deposits on the insides. These types of lime deposits on the insides of cooking vessels are also very common in the region today. To determine the proteins, the research team used novel analysis methods on samples extracted from various sections of the shards as well as from lime scale deposits.
Preserved Food Proteins in Shards of Ceramic Vessels
The analysis showed that the vessels contained cereals, legumes, meat, and dairy products. The scientists were able to show that the dairy products came mainly from sheep and goats, and in some cases, from cows. "Bones from these species are routinely found at the site. Earlier studies had also found milk residues in the form of lipids in vessels from the site, but this is the first time that researchers have been able to pinpoint which animals had produced the milk," explains the coordinator of the study, Dr. Eva Rosenstock at Freie Universität, who also said that the cereal proteins in the shards were found to be barley and wheat. The legumes included peas and certain vicia or vetches. These plants were also detected at the site as macro remains. Other animal products that were processed in the vessels as meat or blood were found to be from goats and sheep, and in some cases, from cattle and deer species. "Interestingly, many of the jars contained residues from several different foods. This means that the inhabitants of the settlement either cooked meals containing several ingredients, such as soup or stew, or that the vessels were used for preparing one food after another. Both explanations are possible," says Dr. Eva Rosenstock.
Early Cheese Production
One vessel had only residues of dairy products in the form of whey specific proteins. "This is particularly interesting because it probably means that the inhabitants of the settlement used a method of milk processing that separated milk into whey and curds. It also means that after separation, whey was stored in a special container and used for other purposes," explains the lead author of the study, Jessica Hendy from the Max Planck Institute for the Science of Human History. The findings indicate that this type of milk processing was practiced in the region at the very latest by the 6th century BC.
The researchers point out that archaeological finds indicate an even wider range of foods, especially plants, was probably eaten in Çatalhöyük, but these other foods are not included in the existing protein databases. The so-called "shotgut" method of protein determination used by the researchers relies on reference databases of protein sequences which do not contain all plant species. "For example, there are only six protein sequences of vetch species in the databases," says Jessica Hendy, "while for wheat there are almost 145,000 species. An important aspect of our future work will be to expand these databases with more reference material."
Further Potential for Protein Analysis of Archaeological Pottery Shards
Protein analysis, in comparison with other molecular analysis techniques that can identify broader food groups such as milk fat or body fat in archaeological ceramic shards, allows for greater detail in researching past nutritional practices. The researchers say their findings indicate that protein analysis has great potential for determining food components in specimens up to 8,000 years old. The calcified residues on the inner sides of the vessels had been extremely well preserved and contributed to a great deal of new insights. Often, however, similar calcifications are routinely removed by archaeologists in cleaning the artefacts. Dr. Eva Rosenstock says, "Our results show how valuable such deposits can be, and we encourage our colleagues to leave them on the shards when cleaning after excavation."
One of the Most Important Early Farming Sites in the Ancient World
The settlement of Çatalhöyük, located in what is today Central Turkey, was built around 7100 BC and inhabited by early farmers until 5600 BC. The settlement has a fascinating architecture in which houses were built together without gaps. It is characterized by unusually well-preserved archaeological finds. The researchers say that after 25 years of excavation and the processing of archaeological artefacts, Çatalhöyük is probably one of the most thoroughly investigated early farming sites in the Ancient World.
Publication
- Ancient proteins from ceramic vessels at Çatalhöyük West reveal the hidden cuisine of early farmers
- Authors: Jessica Hendy, Andre C. Colonese, Ingmar Franz, Ricardo Fernandes, Roman Fischer, David Orton, Alexandre Lucquin, Luke Spindler, Jana Anvari, Elizabeth Stroud, Peter F. Biehl, Camilla Speller, Nicole Boivin, Meaghan Mackie, Rosa R. Jersie-Christensen, Jesper V. Olsen, Matthew J. Collins, Oliver E. Craig, Eva Rosenstock
- Nature Communications , DOI: 10.1038/s41467-018-06335-