求面包的起源、发展或者历史英文介绍要英文介绍

History of bread
Bread is one of the oldest prepared foods.Evidence from 30,000 years ago in Europe revealed starch residue on rocks used for pounding plants.It is possible that during this time,starch extract from the roots of plants,such as cattails and ferns,was spread on a flat rock,placed over a fire and cooked into a primitive form of flatbread.Around 10,000 BC,with the dawn of the Neolithic age and the spread of agriculture,grains became the mainstay of making bread.Yeast spores are ubiquitous,including the surface of cereal grains,so any dough left to rest will become naturally leavened.There were multiple sources of leavening available for early bread.Airborne yeasts could be harnessed by leaving uncooked dough exposed to air for some time before cooking.Pliny the Elder reported that the Gauls and Iberians used the foam skimmed from beer to produce "a lighter kind of bread than other peoples." Parts of the ancient world that drank wine instead of beer used a paste composed of grape juice and flour that was allowed to begin fermenting,or wheat bran steeped in wine,as a source for yeast.The most common source of leavening was to retain a piece of dough from the previous day to use as a form of sourdough starter.
A major advance happened in 1961 with the development of the Chorleywood bread process,which used the intense mechanical working of dough to dramatically reduce the fermentation period and the time taken to produce a loaf.The process,whose high-energy mixing allows for the use of lower protein grain,is now widely used around the world in large factories.
Recently,domestic bread machines which automate the process of making bread have become popular.