In a remarkable twist of history, researchers in China have uncovered what they believe to be the world's oldest cheese, found in a 3,600-year-old tomb at the Xiaohe Cemetery in Xinjiang province. This discovery not only tantalizes the palate but also opens a window into the cultural practices and dietary adaptations of Bronze Age populations.
The cheese, identified as kefir, was discovered laid across the body of a young woman in a coffin excavated in 2003. Recent DNA analysis by the Chinese Academy of Sciences revealed traces of both goat and cow milk in the samples. This finding underscores the significance of dairy in the diets of the Xiaohe peoples, particularly given their known lactose intolerance. The fermentation process used to produce this cheese likely allowed them to incorporate dairy into their diets by significantly reducing lactose levels and extending the shelf life of milk.
However, this ancient cheese is not suitable for consumption today; it has transformed into a dry, dense substance over the millennia. Fu Qiaomei, a paleogeneticist involved in the study, remarked, “Regular cheese is soft. This is not. It has now become really dry, dense and hard dust.” While it may not be a culinary delight, the cheese offers vital insights into human cultural development and its impact on microbial evolution.
The researchers' findings suggest that kefir may have spread from Xinjiang to inland East Asia, providing a new perspective on the migration of ancient populations. Additionally, the analysis of bacterial specimens in the cheese has allowed scientists to trace the evolution of Lactobacillus species, crucial for fermentation, and to identify a subspecies with probiotic qualities. This research highlights the role of human intervention in the evolution of these beneficial bacteria, which could have implications for addressing antibiotic resistance today.
With the earliest evidence of milk fermentation dating back to around 6,000-4,000 BC, this discovery enriches our understanding of prehistoric dietary practices and the complex interactions between humans and microbes. As we continue to explore the past, such findings remind us of the intricate tapestry of human history and the ongoing evolution of our relationship with food.