A Bronze Age dairy operation
At the archaeological site of Koktepa, about 30 kilometers north of Samarkand, excavations uncovered large ceramic vessels from the Early Bronze Age. Analysis of the residue inside these jars provided direct evidence for a surprisingly early dairy operation. Scientists identified the presence of calcium oxalate, a compound that precipitates during fermentation and is often called "beerstone." By examining the specific shape, or morphology, of the calcium oxalate crystals, researchers can determine the liquid of origin.
The crystal structure found in the Koktepa vessels did not match residues from fermented grains or common livestock milk like that from cows or goats. Instead, the morphology was a clear match for crystals formed during the fermentation of mare's milk. This chemical fingerprint confirms that the inhabitants of this region were keeping horses, but actively milking them and fermenting that milk around 2800 BCE. The discovery represents some of the earliest direct evidence for the production of kumis, a fermented mare's milk beverage still consumed in Central Asia today.