All bread was unleavened and early humans made bread by mixing variety of crushed grains with water then spreading the mixture on stones to bake in the sun.
The leavened bread was probably made by accident by a royal baker in the Nile Valley in Egypt. Perhaps a batch of dough was allowed to stand before it was baked. Wild yeast cells settled in and grew, producing tiny bubbles of carbon dioxide and making the dough rise.
It was between 3500 and 3000 BC, the Egyptian discovered – the fermentation. The Egyptians invented the closed oven and bread assumed great significance. Homage was paid to Osiris, the god of grain, and bread was used instead of money; the workers who built the pyramids were paid in bread.
The ancient Egyptians later learned to control the kind of yeast on their bread. Each time they baked, they set aside some of the leavened dough to mix with the next batch.
In Rome during 1000 BC, risen yeasted bread became popular and by 500 BC a circular quern was developed - a circular stone wheel turned on another which was fixed. The Romans sometimes used a leaven made of grape juice and millet to hasten the fermentation of their breads.
Ancient leavened bread
