Prehistoric cheese-making ability discovered in pottery by Polish archaeologists

The history of cheese received an important update yesterday, when it was reported that a team of archaeologists digging along the banks of the Vistula River in Poland unearthed hole-studded shards of pottery, dating from 7,500 years ago, that have been conclusively identified as cheese strainers.

Now, if you're thinking from that opening statement that I'm making light of this discovery, I'm not. The history of cheese is actually a very important part of the development of our culture and society.

Tolerance of lactose in adult humans — called lactase persistence — is a relatively recent development, and at a time before this tolerance spread in the population, separating milk into low-lactose curds and high-lactose whey allowed early humans to carry and store a very convenient source of protein.

"Making cheese is a particularly efficient way to exploit the nutritional benefits of milk, without becoming ill because of the lactose," said Princeton University archaeologist Peter Bogucki, according to the Wall Street Journal.

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Bogucki noted the perforated pottery shards during his 35 years work at the Polish dig sites, but it wasn't until the early '80s that he figured out what they might have been for. Visiting with friends in Vermont, he noticed their ceramic cheese strainers, and the similarities between them and the shards the archaeological team had found.

"It set off a few bells ringing," he said, according to the LA Times.

His idea was only one of several competing hypotheses at the time, though. Others thought that they may have been part of vessels to hold burning coals, or perhaps to separate honey from honeycombs, or even in the brewing of beer.

Richard P. Evershed, a professor of biogeochemistry at the University of Bristol, became interested in Bogucki's idea, though, and gathered a team to investigate his hypothesis.

Melanie Salque, one of Evershed's doctoral students at the time, examined small fragments of the pottery by cleaning them of any contaminants, crushing them into a fine powder and extracting any fats that she found. Testing these fats found that they were animal fats (as opposed to those from plants or beeswax), and measuring the carbon isotopes in the fats revealed that they were from milk.

Similar milk fats were found in clay pots excavated in Turkey, which are dated at roughly 500 years before the ones found in Poland. However, the finds in Turkey, while they suggested cheese making, were not conclusive as they could have held any kind of milk product. These shards from Poland, though, with their perforations, would be quite useless for simply storing milk or other less-solid milk products, provide much stronger evidence.

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"Scholars have been duking it out for decades as to what these sieves were used for," said Paul Kindstedt, University of Vermont chemist and author of Cheese and Culture: A History of Cheese and Its Place in Western Civilization, who was not involved in the research. "This new finding is really definitive —beyond a reasonable doubt—that this utensil was used for cheese making."