The well-aged cheese dates back to roughly 1615 BCE. It's been ripening underground, alongside its mummy possessors, in northwest China for some 3,400 years.
"We not only identified the product as the earliest known cheese, but we also have direct … evidence of ancient technology," study author Andrej Shevchenko, an analytical chemist at Germany's Max Planck Institute of Molecular Cell Biology and Genetics, told USA Today.
Researchers at the institute say their analysis proves the cheese was made by combining milk with a "starter," a mix of bacteria and yeast. It's the method used today to make kefir and kefir cheese, a plan, simple cheese similar to cottage cheese.
Most cheese throughout history has been made using rennet, an enzyme in the stomachs of young domestic animals -- like a calf, lamb or kid -- that causes milk to separate into solids and liquid, or curds and whey. Historians believe cheese was first discovered on accident by people transporting milk in pouches made of animal gut. But rennet demands the slaughter of a young animal, a risky proposition for early settlers and nomadic peoples.
But as Shevchenko points out, the kefir technology is "easy, cheap … It's a technology for the common people." He and his colleagues think it's a technology that could have helped the spur the spread of animal herding throughout Asia, having made its way east along the early trade routes from the Middle East.
The nuances of their claims and the methods used to test the ancient cheese will be laid out in the upcoming issue of the Journal of Archaeological Science.
Oliver Craig of the University of York in Britain told USA Today he's skeptical of the kefir technology hypothesis, pointing out that proteins in the cheese have likely decayed too much to provide certainty of its original method of production.
Still, Craig said its very existence is astounding. For any ordinary cheese left out to the elements, Craig pointed out, "bacteria will get in and start to eat it away, liquefy it. It's just amazing it survived."
That scientist are even able to debate the technological origins of a 3,400-year-old chunk of cheese is thanks to the Small River Cemetery Number 5, in northwestern China, the burial site of a little-understood Bronze Age people.
First discovered by a Swedish archaeologist in the 1930s, the area in China's Taklamakan Desert features the perfect mix of dry air and salty soil -- a natural refrigerator for the world's oldest cheese.