Milk production and dairy processing allowed early farmers to produce food without slaughtering precious livestock, and making cheese turned milk into a less perishable food that was more digestible for a population who at the time would have been intolerant to the lactose contained in milk.

Researchers from the University of Bristol in Britain, with colleagues in the United States and Poland, analyzed fatty acids embedded in prehistoric pottery from the Polish region of Kuyavia, and found they had been used to separate milk into fat-rich curds for cheese and lactose-containing whey.

"The presence of milk residues in sieves ... constitutes the earliest direct evidence for cheese-making," said Mélanie Salque from Bristol, one of the authors of the research, which was published in the journal Nature.

Peter Bogucki, another researcher involved in the work, said: "Making cheese allowed them to reduce the lactose content of milk, and we know that, at that time, most of the humans were not tolerant to lactose."

Milk residues have been found at ancient sites up to 8,000 years old in Turkey and Libya, but there was no evidence that the milk had been processed into cheese.

Until now, the earliest evidence of cheese-making came from depictions of milk processing in murals several thousand years younger than the pottery fragments.

The researchers believe other vessels found in the same region were used for other specific purposes. Jars lined with beeswax were probably for storing water, and pottery containing the remnants of carcass fats was probably used for cooking meat.

"It is truly remarkable, the depth of insights into ancient human diet and food processing technologies these ancient fats preserved in archaeological ceramics are now providing us with," said Richard Evershed, who heads the Bristol team.

(Reporting by Chris Wickham; Editing by Kevin Liffey)

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