As USA Today reports, the cheese was found in clumps on the bodies of well-preserved mummies (including the one shown above) in China’s Small River Cemetery Number 5. The location is unique, because bodies interred in the region were essentially freeze-dried, meaning their features, clothing, and culinary accompaniments are still discernible even thousands of years later. In large part, that incredible preservation is due to a combination of dry air, salty earth, and tightly-sealed burial conditions.

The cheese itself, which was found over a series of archeological digs dating back to 2002, was identified using analysis of protein and fat content. Investigators speculate that the cheese was made using a kefir starter (bacteria and yeast) which is then combined with milk. The majority of today’s cheeses, in contrast, rely on rennet — an enzyme taken from an animal’s gut — to curdle milk and yield a final product. But the kefir strategy, researchers say, makes sense: it’s significantly easier because it doesn’t necessitate the slaughter of a young animal, and kefir-based cheese is lower in lactose, which aligns with the prevalent lactose intolerance among Asian populations. More details on the researchers’ methods and analyses will be laid out in a forthcoming issue of the Journal of Archaeological Science.