Flour bleaching agent
Encyclopedia
Flour bleaching agent is a food additive
added to flour
in order to make it appear whiter (freshly milled flour is yellowish) and to oxidize the surfaces of the flour grains and help with developing of gluten
.
Usual bleach
ing agents are:
Use of chlorine, bromate
s, and peroxide
s is not allowed in the European Union
.
Flours treated with bleaches and improving agents
generally show higher loaf volume and finer grain. However, people with very sensitive palate
s can detect a slight bitter aftertaste
.
Chlorinated cake flour improves the structure forming capacity, allowing the use of dough formulas with lower proportions of flour and higher proportions of sugar. In biscuit
manufacturing, chlorination of flour is used to control the spread – treated flour reduces the spread and provides a tighter surface. The changes of functional properties of the flour proteins are likely to be caused by their oxidation.
In countries where bleached flour is prohibited, plain flour can be treated in a domestic microwave to produce similar chemical changes to the bleaching process. This improves the final texture of baked goods made to recipes intended for bleached flours.
There is a misconception that alloxan
, a destroyer of beta cells in the pancreas, is used to bleach flour. Though the process of bleaching flour can produce trace amounts of alloxan, it has never been proved to be a problem or to build up in the body.
Food additive
Food additives are substances added to food to preserve flavor or enhance its taste and appearance.Some additives have been used for centuries; for example, preserving food by pickling , salting, as with bacon, preserving sweets or using sulfur dioxide as in some wines...
added to flour
Flour
Flour is a powder which is made by grinding cereal grains, other seeds or roots . It is the main ingredient of bread, which is a staple food for many cultures, making the availability of adequate supplies of flour a major economic and political issue at various times throughout history...
in order to make it appear whiter (freshly milled flour is yellowish) and to oxidize the surfaces of the flour grains and help with developing of gluten
Gluten
Gluten is a protein composite found in foods processed from wheat and related grain species, including barley and rye...
.
Usual bleach
Bleach
Bleach refers to a number of chemicals that remove color, whiten, or disinfect, often via oxidation. Common chemical bleaches include household chlorine bleach , lye, oxygen bleach , and bleaching powder...
ing agents are:
- Organic peroxideOrganic peroxideOrganic peroxides are organic compounds containing the peroxide functional group . If the R' is hydrogen, the compound is called an organic hydroperoxide. Peresters have general structure RCOOR. The O-O bond easily breaks and forms free radicals of the form RO·...
s, namely benzoyl peroxideBenzoyl peroxideBenzoyl peroxide is an organic compound in the peroxide family. It consists of two benzoyl groups bridged by a peroxide link. Its structural formula is [C6H5C]2O2. It is one of the most important organic peroxides in terms of applications and the scale of its production... - Calcium peroxideCalcium peroxideCalcium peroxide is a solid peroxide with a white or yellowish color. For all practical purposes calcium peroxide is insoluble in water but will dissolve in acid to form hydrogen peroxide...
- Nitrogen dioxideNitrogen dioxideNitrogen dioxide is the chemical compound with the formula it is one of several nitrogen oxides. is an intermediate in the industrial synthesis of nitric acid, millions of tons of which are produced each year. This reddish-brown toxic gas has a characteristic sharp, biting odor and is a prominent...
- ChlorineChlorineChlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...
- Chlorine dioxideChlorine dioxideChlorine dioxide is a chemical compound with the formula ClO2. This yellowish-green gas crystallizes as bright orange crystals at −59 °C. As one of several oxides of chlorine, it is a potent and useful oxidizing agent used in water treatment and in bleaching....
- AzodicarbonamideAzodicarbonamideAzodicarbonamide, or azobisformamide, is a synthetic chemical with the molecular formula C2H4O2N4. It is a yellow to orange red, odorless, crystalline powder. As a food additive, it is known by the E number E927.-Use as a food additive:...
- Atmospheric oxygenOxygenOxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
, used during natural aging of flour
Use of chlorine, bromate
Bromate
The bromate anion, BrO, is a bromine-based oxoanion. A bromate is a chemical compound that contains this ion. Examples of bromates include sodium bromate, , and potassium bromate, .Bromates are formed many different ways in municipal drinking water...
s, and peroxide
Peroxide
A peroxide is a compound containing an oxygen–oxygen single bond or the peroxide anion .The O−O group is called the peroxide group or peroxo group. In contrast to oxide ions, the oxygen atoms in the peroxide ion have an oxidation state of −1.The simplest stable peroxide is hydrogen peroxide...
s is not allowed in the European Union
European Union
The European Union is an economic and political union of 27 independent member states which are located primarily in Europe. The EU traces its origins from the European Coal and Steel Community and the European Economic Community , formed by six countries in 1958...
.
Flours treated with bleaches and improving agents
Flour treatment agent
Flour treatment agents are food additives combined with flour to improve baking functionality...
generally show higher loaf volume and finer grain. However, people with very sensitive palate
Palate
The palate is the roof of the mouth in humans and other mammals. It separates the oral cavity from the nasal cavity. A similar structure is found in crocodilians, but, in most other tetrapods, the oral and nasal cavities are not truly separate. The palate is divided into two parts, the anterior...
s can detect a slight bitter aftertaste
Aftertaste
Aftertaste is the taste intensity of a food or beverage that is perceived immediately after that food or beverage is removed from the mouth. The aftertastes of different foods and beverages can vary by intensity and over time, but the unifying feature of aftertaste is that it is perceived after a...
.
Chlorinated cake flour improves the structure forming capacity, allowing the use of dough formulas with lower proportions of flour and higher proportions of sugar. In biscuit
Biscuit
A biscuit is a baked, edible, and commonly flour-based product. The term is used to apply to two distinctly different products in North America and the Commonwealth Nations....
manufacturing, chlorination of flour is used to control the spread – treated flour reduces the spread and provides a tighter surface. The changes of functional properties of the flour proteins are likely to be caused by their oxidation.
In countries where bleached flour is prohibited, plain flour can be treated in a domestic microwave to produce similar chemical changes to the bleaching process. This improves the final texture of baked goods made to recipes intended for bleached flours.
There is a misconception that alloxan
Alloxan
Alloxan is an oxygenated pyrimidine derivative. It is present as alloxan hydrate in aqueous solution.-History:...
, a destroyer of beta cells in the pancreas, is used to bleach flour. Though the process of bleaching flour can produce trace amounts of alloxan, it has never been proved to be a problem or to build up in the body.