Most archaeological evidence, however, suggests that fermentation was being used in one manner or another by around 4000 to 3500 B. Some of this evidence-from an ancient Mesopotamian trading outpost called Godin Tepe in present-day Iran- indicates that barley was being fermented at that location around 3500 B. Additional evidence recoverd at Hacinegi Tepe (a similar site in southern Turkey) also suggest that ancient Mesopotamians were fermenting barley at a very early date...

There is no question that fermentation takes place accidentally (as it must have done countless times before humans learned something about controlling the process), and most investigators believe that barley was first cultivated in the Fertile Crescent region of lower Mesopotamia between the Tigris and Euphrates rivers.

These ovens or hearths took the form of clay-covered hollows in the floor which were heated with burning wood.

When the heat was sufficient the embers were raked out and the pieces of dough placed in the hollows and covered over.

"No one has yet managed to date the origins of beer with any precision, and it is probably an impossible task.

Indeed, there are scholars who have theorized that a taste for ale prompted the beginning of agriculture, in which case humans have been brewing for some 10,000 years...

Although some of the early Roman ovens had chimnesy to improve the draught and carry away steam, it was many centuries before chimneys were commonly used or dampers incorporated so that the heat could be more effectively controlled." ---The Story of Bread, Ronald Sheppard & Edward Newton [Charles T. 107-109) ""When I break your staff ten women shall bake your bread in one oven, and shall deliver your bread again by weight; and you shall eat, and not be satsified." ---Lev. This type of oven may have been a small earthenware cylindar called tannur in the Bible as it is by present-day rural north Africans who still use it.

A fire is kindled in the bottom and the dough is slapped against the hot interior walls, yielding curved disks of bread.The loaves were then broken up and put to soak in water, where they were allowed to ferment for about a day before the liquor was strained off and considered ready for drinking." ---Food in History, Reay Tannahill [Three Rivers Press: New York] 1988 (p.48) "Leavening, according to one theory, was discovered when some yeast spores--the air is full of them, especially in a bakehouse that is also a brewery--drifted onto a dough that had been set aside for a while before baking; the dough would rise, not very much, perhaps, but enough to make the bread lighter and more appetizing than usual, and afterwards, as so often in the ancient world, inquiring minds set about the task of reproducing deliberately a process that had been discovered by accident.But there is an alternative and even more likely theory-that on some occasion ale instead of water was used to mix the dough.The lower section formed the fire-box in which were burned pieces of dried wood, foten taken from the Nile, or even dried animal dung.The upper part, accessible from the top, was the baking chamber.Grain is heavy to transport relative to the beer made from it, so it is not surprising that there may be evidence of ale in these outposts and not unreasonable to suspect that accidental fermentation did occur at some point in the ancient Mesopotamian region, leading to beer making." ---Cambridge World History of Food, Kenneth F.