Grinding Grain
It now seems that humans began to grind grain into flour earlier than was originally thought. Grinding stones have been found at African and Asian sites dating from 200,000-50,000 years ago It was presumed at first that these stones were used primarily to grind plant and animal materials, or minerals, to make pigments, rather than for the preparation of foodstuffs. However, new findings from the Middle East raise the intriguing possibility that some human groups may have been using grinding stones to process cereal grains, such as wheat, and maybe other types of edible plant, as early as the Middle Paleolithic Era(i.e. 50,000 years ago and earlier). But why is it such an advantage to grind cereal grains before eating them? The main reason is that grinding breaks down the hard, fibrous cereal grain to release the easily digestible starch granules contained within This served two purposes. Firstly, it enabled people to save enormously on the wear and tear of their teeth, compared to eating raw unprocessed grains. Unlike the teeth of grazing animals, human teeth do not continue to grow after childhood. Tooth wear due to a diet high in fiber and raw plants can result in the substantial erosion of molars (back teeth by early adulthood. People with worn or absent teeth faced starvation unless they could find alternative types of food that did not require chewing. Alternatively, they could try to find another way of grinding the fibrous plant material before eating it. Perhaps it was one of these incentives that led to the use of stone grinding tools for seed processing.
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