The history of bread goes back at least 30,000 years. The first bread produced was probably cooked versions of a grain-paste, made from roasted and ground cereal grains and water, and may have been developed by accidental cooking or deliberate experimentation with water and grain flour. Descendants of these early flatbreads are still commonly made from various grains in many parts of the world, including Armenian lavashs and Iranian sangaks, taboons, Mexican tortilla, Indian bread chapati, roti and naan, Scottish oatcake, North American johnnycake, Jewish Matzo, Middle Eastern pita, and Ethiopian injera. Flat bread of these types also formed a staple in the diet of many early civilizations with the Sumerians eating a type of barley flat cake, and the 12th century BC Egyptians being able to purchase a flat bread called ta from stalls in the village streets. The ritual bread in ancient Greek offerings to the chthonic gods, known as psadista was made of fine flour, oil and wine.

 

The earliest archaeological evidence for flour, which was probably processed into an unleavened bread, dates to the Upper Paleolithic in Europe, around 30,000 years ago. During this period of human history cereals constituted just one of many food sources exploited by hunting and gathering;[4] palaeolithic European diets were based mainly on animal proteins and fats.[3] Cereals and bread became a staple food during the Neolithic, around 10,000 years ago, when wheat and barley were among the first plants to be domesticated in the Fertile Crescent. Wheat-based agriculture spread from Southwest Asia to Europe, North Africa and the Indian Subcontinent. In other parts of the world cereals such as rice (East Asia), maize (the Americas) and sorghum (sub-Saharan Africa), which are also sometimes made into bread, were independently domesticated and formed the basis of alternative agricultural systems.[5] Around the world, the shift from varied hunter-gatherer subsistence to agricultural diets based predominantly on a cereal staple such as wheat bread marked an important turning point in human history. Though in many ways nutritionally deficient compared to hunting and gathering, cereal crops allowed agricultural societies to sustain much larger populations than had previously been possible, which in turn led to greater economic specialisation, social complexity and eventually the rise of civilised states.

 

The development of leavened bread can also probably be traced to prehistoric times. Yeast spores occur everywhere, including the surface of cereal grains, so any dough left to rest will become naturally leavened. Although leavening probably has prehistoric origins, the earliest archaeological evidence of it is from ancient Egypt. Scanning electron microscopy has detected yeast cells in some ancient Egyptian loaves. However, ancient Egyptian bread was made from emmer wheat and has a dense crumb. In cases where yeast cells are not visible, it is difficult, by visual examination, to determine whether the bread was leavened. As a result, the extent to which bread was leavened in ancient Egypt remains uncertain.

 

The importance of bread in the formation of early human societies cannot be overstated. From the western half of Asia, where wheat was domesticated, cultivation spread north and west, to Europe and North Africa, and enabled humans to become farmers rather than hunters and foragers. This in turn led to the formation of towns, as opposed to the nomadic lifestyle, and gave rise to more and more sophisticated forms of societal organization. Similar developments occurred in eastern Asia, centered on rice, and in the Americas with maize.

 

The industrialization of bread-baking was a formative step in the creation of the modern world. Otto Frederick Rohwedder is considered to be the father of sliced bread. In 1912 Rohwedder started work on inventing a machine that sliced bread, but bakeries were reluctant to use it since they were concerned the sliced bread would go stale. It was not until 1928, when Rohwedder invented a machine that both sliced and wrapped the bread, that sliced bread caught on. A bakery in Chillicothe, Missouri was the first to use this machine to produce sliced bread.

 

For generations, white bread was the preferred bread of the rich while the poor ate dark (whole grain) bread. However, in most western societies, the connotations reversed in the late 20th century, with whole grain bread becoming preferred as having superior nutritional value while white bread became associated with lower-class ignorance of nutrition.

 

Another major change 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 at the expense of taste and nutrition. The process, whose high-energy mixing allows for the use of inferior grain, is now widely used around the world in large factories. In total contrast, traditional breadmaking is extremely time-consuming, as the dough is mixed with yeast and requires several cycles of kneading and resting in order to become ready for baking, and to produce the desired flavor and texture.

 

More recently, and especially in smaller retail bakeries, chemical additives are used that both speed up mixing time and reduce necessary fermentation time, so that a batch of bread may be mixed, made up, risen, and baked in fewer than three hours. Dough that does not require fermentation because of chemical additives is called "quick bread" by commercial bakers. Common additives include reducing agents such as L-cysteine or sodium metabisulfite, and oxidants such as potassium bromate or ascorbic acid.

 

Often these chemicals are added to dough in the form of a prepackaged base, which also contains most or all of the dough's non-flour ingredients. Using such bases and sophisticated chemistry, it has been possible for commercial bakers to make imitations of artisan and sourdough breads, traditionally made by semi-skilled laborers working in smaller shops. Since 1986, domestic breadmakers that automate the process of making bread have become popular in the home.

Staling, or "going stale" (the verb to stale is used in the food industry), is a chemical and physical process in bread and other foods that reduces their palatability. Stale bread is dry and leathery.

 

Staling is not, as is commonly believed, simply a drying-out process due to evaporation. Bread will stale even in a moist environment, and stales most rapidly at temperatures just above freezing.[1] Bread stored in the refrigerator will have increased staling rates and should therefore be kept at room temperature. However, refrigeration delays the growth of mold and extends the shelf life of bread.

One important mechanism is the migration of moisture from the starch granules into the interstitial spaces, degelatinizing the starch. The starch amylose and amylopectin molecules realign themselves causing recrystalisation. This results in stale bread's leathery, hard texture. Additionally, pleasant "fresh" flavor is lost to the air, and often unpleasant flavor is absorbed from it as well, especially in a confined space with other food such as arefrigerator.