Flour bleaching agent is a food additive added to flour in order to make it appear whiter (freshly milled flour has a yellowish tint) and to oxidize the surfaces of the flour grains and help with developing of gluten.
Usual bleaching agents are:
- Organic peroxides, namely benzoyl peroxide
- Calcium peroxide
- Nitrogen dioxide
- Chlorine
- Chlorine dioxide
- Azodicarbonamide
- Atmospheric oxygen, used during natural aging of flour
Use of chlorine, bromates, and peroxides 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 palates 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 oven 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.
Famous quotes containing the words flour, bleaching and/or agent:
“Mathematics may be compared to a mill of exquisite workmanship, which grinds your stuff to any degree of fineness; but, nevertheless, what you get out depends on what you put in; and as the grandest mill in the world will not extract wheat flour from peascods, so pages of formulae will not get a definite result out of loose data.”
—Thomas Henry Huxley (1825–1895)
“Worn down by the hoofs of millions of half-wild Texas cattle driven along it to the railheads in Kansas, the trail was a bare, brown, dusty strip hundreds of miles long, lined with the bleaching bones of longhorns and cow ponies. Here and there a broken-down chuck wagon or a small mound marking the grave of some cowhand buried by his partners “on the lone prairie” gave evidence to the hardships of the journey.”
—For the State of Kansas, U.S. public relief program (1935-1943)
“The average American is a good sport, plays by the rules. But this war is no game. And no secret agent is a hero or a good sport—that is, no living agent.”
—John Monks, Jr., U.S. screenwriter, Sy Bartlett, and Henry Hathaway. Robert Sharkey (James Cagney)