Scientists have found the earliest direct evidence of human consumption of milk.
The team identifies the milk protein embedded in the dental plaque on the teeth of prehistoric farmers from the UK.
It shows that people consumed dairy products as early as 6,000 years ago ̵
This might suggest that they process raw milk into cheese, yogurt, or some other fermented product.
This would reduce its lactose content, making it more enjoyable.
The team members scraped plaque samples from the tooth, separated the various components into the tooth, and analyzed them using mass spectrometry.
They discover a milk protein called beta-lactoglobulin (BLG) in the tartar of seven individuals, spanning early to mid Neolithic times.
"Proteomic analysis of calculus is a fairly recent technique. There have been several studies before, but they are usually historically archaeological rather than prehistoric material," co-author Dr Sophie Charlton of the Department of Archeology at York University told the BBC News.
- The decomposition of milk is the "more recent ascent"
- Ancient Britons "replaced" by newcomers  Copyright
Lactose intolerance arises from the inability to absorb the lactose sugar contained in milk after infancy. This means that consuming milk-based foods can lead to uncomfortable symptoms such as abdominal pain, diarrhea and nausea. However, many modern Europeans have a genetic mutation that allows long-term consumption of milk into adulthood.
This mutation affects a portion of the DNA that controls the activity of the lactase gene, an enzyme that breaks down lactose sugar. However, previous studies on the genetics of Neolithic Europeans have shown that they lack this mutation.
Dr. Charlton says that these Stone Age people may be limited to small amounts of milk. "If you have lactose intolerance and consume very, very small amounts of milk, it doesn't do you any harm. You can handle it," she explained.
But Dr. Charlton added: "An alternative option that I think might be a little more plausible is that they have processed the milk in such a way that it eliminates lactose. So if you process it in cheese , or fermented dairy, or yogurt, then it reduces the lactose content so you can digest it more easily.
"This idea fits in quite well with other archaeological evidence of the period when we find milk fat in many neolithic ceramics, both in the UK and in the east rest of Europe. "
In addition, some of the milk residues found in these pots appear to have been heated, which would be necessary for processing raw milk into cheese or other product. sites: Himboldon Hill in Dorset, Hazleton North in Gloucestershire and Bunbury Lane in Northamptonshire.
More than a quarter of pottery fragments in Himboldon Hill have milk lipids, suggesting that dairy foods are very important to people living on this site. Other neolithic sites show evidence of flocks of animals that are consistent with those used for milk processing.
Genetic studies of ancient populations from across Eurasia show that lactase persistence has become common only recently, despite the consumption of dairy products in the Neolithic. The mutation has started to appear since the Bronze Age, but even at that time it is only present in 5-10% of Europeans.
The Neolithic era in Britain lasted from about 6,000 to 4,400 years and had the introduction of agriculture, including the use of domestic animals such as cows, sheep, pigs and goats.
The study was published in the journal Archaeological and Anthropological Sciences.
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