In many countries, commercial bread often contains additives to improve flavor, texture, color, shelf life, nutrition, and ease of production. Bread is one of the oldest prepared foods. Evidence from 30,000 years ago in Europe and Australia revealed starch residue on rocks used for pounding plants. An early leavened bread buckwheat loaf baked as early as 6000 BC in southern Mesopotamia, cradle of the Sumerian civilization, who may have passed on the knowledge to the Egyptians around 3000 BC.
The Egyptians refined the process and started adding yeast to the flour. 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. The ancient Egyptians, Greeks, and Romans all considered the degree of refinement in the bakery arts as a sign of civilization.
Gluten-free breads are made using flours from a variety of ingredients such as almonds, rice, sorghum, corn, legumes such as beans, and tubers such as cassava. Since these foods lack gluten, dough made from them may not hold its shape as the loaves rise, and their crumb may be dense with little aeration. In wheat, phenolic compounds are mainly found in hulls in the form of insoluble bound ferulic acid, where it is relevant to wheat resistance to fungal diseases. Rye bread contains phenolic acids and ferulic acid dehydrodimers. Glutenin and gliadin are functional proteins found in wheat bread that contribute to the structure of bread.
Glutenin forms interconnected gluten networks within bread through interchain disulfide bonds. Gliadin binds weakly to the gluten network established by glutenin via intrachain disulfide bonds. Acrylamide is neurotoxic, has adverse effects on male reproduction and developmental toxicity and is carcinogenic. The high proportion of FODMAP carbohydrates in such bread then causes flatulence. It is most commonly eaten with the hands, either by itself or as a carrier for other foods.
Nutritionally, bread is categorized as a source of grains in the food pyramid. Further, it is a good source of carbohydrates and nutrients such as magnesium, iron, selenium, B vitamins, and dietary fiber. Bread crust is formed from surface dough during the cooking process. It is hardened and browned through the Maillard reaction using the sugars and amino acids due to the intense heat at the bread surface. The crust of most breads is harder, and more complexly and intensely flavored, than the rest. Methods of processing dough into bread include the straight dough process, the sourdough process, the Chorleywood bread process and the sponge and dough process. Professional bread recipes are stated using the baker’s percentage notation.
Measurement by weight is more accurate and consistent than measurement by volume, particularly for dry ingredients. Calcium propionate is commonly added by commercial bakeries to retard the growth of molds. Flour is grain ground to a powdery consistency. Flour provides the primary structure, starch and protein to the final baked bread.
The protein content of the flour is the best indicator of the quality of the bread dough and the finished bread. Water, or some other liquid, is used to form the flour into a paste or dough. The weight or ratio of liquid required varies between recipes, but a ratio of three parts liquid to five parts flour is common for yeast breads. Recipes that use steam as the primary leavening method may have a liquid content in excess of one part liquid to one part flour. Fats, such as butter, vegetable oils, lard, or that contained in eggs, affect the development of gluten in breads by coating and lubricating the individual strands of protein. They also help to hold the structure together.