Protein analysis of ancient food particles found clinging to ceramic pots at the Friesack 4 archaeological site in Brandenburg, Germany, suggests humans have feasted on caviar for at least 6,000 years.
The findings, newly published in PLoS One, act as a Stone Age cookbook of sorts, outlining ancient humans’ food-preparing process in unprecedented detail: First, Andrew Masterson writes for Cosmos, early cooks likely gathered fresh carp roe eggs—the prime ingredient in caviar—and dropped them into a pot of boiling water or fish broth warmed by poaching on embers. Then, they covered the pot with leaves, either seeking to trap heat within or add another flavor to the meal.
According to Nature, lead author Anna Shevchenko of the Max Planck Institute of Molecular Cell Biology and Genetics in Dresden, Germany, identified the elements of this prehistoric recipe by conducting protein analysis of charred food traces left on a clay cooking vessel dated to around 4,000 B.C.
This technique falls under the burgeoning field of proteomics, or the large-scale study of protein sets. Proteomics allows researchers to hone in on species- or age-specific proteins, affording a higher level of detail than most archaeological assessments of historical food substances.
As Masterson explains, scientists often base ancient food analysis on the presence of biological markers such as isotopes and fats. Indirect evidence—including artifacts, art or writing, and physical sources, like the contents of latrines—also contributes to these assessments.
Although this process often yields accurate results, proteomics takes research to the next level, enabling scientists to separate ancient proteins from contemporary contaminants—in this case, human-derived keratins, food particles transported by archaeologists’ fingers and even a speck of hair gel. Add in the analysis’ ability to extrapolate species-specific proteins, which tell scientists the exact animals and plants found in a sample—as well as changes to proteins’ biological properties triggered by various cooking methods—and you arrive at a stunningly complete portrait of Mesolithic cuisine.
Ultimately, Shevchenko and her colleagues identified about 300 proteins left on 12 shards of a dark brown, unglazed pot known as specimen #3258. The vessel is one of roughly 150,000 artifacts excavated from Friesack 4, an archaeological site first discovered during the 1930s. Additional finds include stoneware vessels and artifacts made of bone, wood and antlers.
By comparing the medley of ancient proteins to fresh samples of carp roe and fish muscle tissue boiled in salty water, the scientists were able to definitively label the 6,000-year-old food remains as carp roe.
But that’s not all: According to the study, the team found traces of bone-in pork on another vessel, indicating the Stone Age hunter-gatherers dined not only on caviar, but also on “pork with bones, sinews or skin.”
In a statement, co-author Günter Wetzel notes, “The fact that the investigations with the new method could be carried out so successfully on the example of over 6,000 years old ceramics from the place of discovery at Friesack should be a milestone in the approach to the habits of our hunter-gatherer ancestors."
At the same time, Wetzel cautions archaeologists to be mindful of how they handful artifacts upon initial excavation. He concludes that the team was lucky that the original excavators did not wash the ceramics after they were discovered.