In 2024, for the first time, scientists have been able to extract DNA out of what is believed to be the world’s oldest cheese, found in the graveyards of the Xiaohe cemetery in China’s Tarim Basin. This ancient dairy product, estimated to be around 3,600 years old, was found smeared around the neck and head of mummies dated back to the Bronze Age. This discovery provides further a look into early cheesemaking and indirectly points to the spread of fermented dairy cultures across ancient Eurasia.
Cheese and Mummification: A Special Find
The ancient cheese was found initially more than a decade ago, as archaeologists first excavated odd clumps of organic matter near the Tarim Basin mummies. People sort of knew it was a dairy product, and only with present-day’s DNA sequencing technology were they able to discover that’s what it was. The cheese—that historians count as an ancestor of kefir—is still familiar today as a fermented dairy product, mummies of which were rather well preserved thanks to the climate of the Xinjiang region, which can be characterized as a desert.
DNA analysis revealed that the cheese harbored microbial cultures similar to those used in the production of kefir today. This is a highly unusual discovery because it means that this constitutes the continuity in practice of dairy fermentation over millennia. The bacterial and yeast strains present in kefir were isolated by scientists, confirming the fact that indeed the fermentation processes adopted today are the same as those thousands of years ago.
The Diffusion of Dairy Cultures across Eurasia
This is not only an interesting fact about the eating habits of ancient people, but it also reflects much light on the pattern of movement of people, goods, and technology in the Bronze Age. Kefir, a common fermented milk preparation from the Caucasus region, was obtained by fermenting milk with the help of granules containing a specific type of microbe. The DNA analysis revealed that the kefir found on the Tarim mummies was made both from cow and goat milk, which assumes the exchange of dairy products and techniques across different parts of Eurasia.
Researchers say the practices of making kefir would have developed independently both in the Xinjiang region and the Caucasus, diffusing down trade routes and through nomadic migrations. This hypothesis corrects the earlier notion that kefir and fermented dairy products were specific only to certain parts of the world, adding to the complexity brought about by early food globalization.
A Window into the Diet and Culture of the Bronze Age
The presence of cheese also in the Tarim Basin mummies speaks volumes about the importance of dairy within the diet of these people. Archaeologists speculate that it might have been used in some sort of burial ritual, or it could be part of the daily diet of those buried in the region. The Tarim mummies are known for their uniqueness in preservation, since the conditions of an arid desert allow human remains and even foodstuffs, like cheese, to survive intact for thousands of years.
It was unique in its region, once supplied by an ancient river system that created a verdant environment. During the change in course that the river took, the desert began to creep into its place and ended up naturally mummifying bodies. Thus, the cheese, together with textiles and other artifacts, has been preserved as an invaluable time capsule of life in the Bronze Age.
Implications for Understanding Ancient Microbial Life
Besides the historical value of the finding, this ancient cheese is a rare opportunity for studying ancient microbial diversity. Before food production was industrialized, people used an immense variety of microbes to ferment all kinds of food products. Most of those “heirloom” microbes have been lost over time and replaced by only a few that were selected due to their high productivity. Preserved within the Tarim Basin mummies’ cheese, these ancient microbial communities are now available for scientists to study the microbiota that might have played a significant role in the evolution of human diets.
By comparing this microbial DNA with modern strains, researchers are gleaning new information about the evolution of dairy fermentation and the role microbes have played in human society. Such studies not only provide a window into the past but also help researchers understand how ancient diets might have influenced human health and culture.
Questions Remain
Despite all the excitement about this discovery, many questions remain. For instance, the precise migration route by which fermentation of kefir came about is still unknown. While genetic evidence indicates a possibility of multiple origins of domesticated kefir-making practices, the absence of archaeological data on preserved dairy products makes definite statements impossible. Some experts, however, urge a little more research into the matter before the whole story of this ancient kefir can be told, since DNA samples from this old cheese are damaged and incomplete.
But this find has really opened new ways of exploring the links between food, culture, and migration in ancient human societies. And as long as new techniques continue to be developed, it is likely that more secrets will be unearthed from the Tarim Basin mummies—and from other archaeological sites around the world.
Conclusion
It was an extraordinary feat of extracting DNA from the world’s oldest cheese, which was found on mummies in China’s Tarim Basin, and thus bridging ancient history with modern science. This also opened up a window not only into Bronze Age diets but also into how cheesemaking first developed and migrated across cultures. This is a testament to the role of dairy in human societies and gives new insights into the microbial world that helped shape ancient diets. There is still much to be learned, but this ancient cheese has already given a lot to the study of early human history.
