bleaching
Quick Summary
Bleach is a chemical used to whiten or remove the natural color from fibers, yarns, textiles, and paper. It's also used as a disinfectant due to its microbicidal properties. Historically, sunlight was the primary bleaching agent until chlorine was discovered in 1774. Later, bleaching powder, a combination of chlorine and slaked lime, became common. Today, liquefied chlorine, sodium hypochlorite, and hydrogen peroxide are widely used. Different materials require specific bleaching agents; for instance, cotton is often bleached with hydrogen peroxide, while wood and animal fibers use acidic reducing agents like sulfur dioxide. Optical bleaches, which emit a bluish-white light, are not true bleaches. Dilute sodium hypochlorite solutions are used for sanitizing food-processing equipment, and stronger solutions are used in settings like hospitals for disinfection.1
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flour…(separated from bran and germ), bleached or unbleached, and suitable for any recipe not requiring a special flour; cake flour, refined and bleached, with very fine texture; self-rising flour, refined and bleached, with added leavening and salt; and enriched flour, refined and bleached, with added nutrients.
Read More…(separated from bran and germ), bleached or unbleached, and suitable for any recipe not requiring a special flour; cake flour, refined and bleached, with very fine texture; self-rising flour, refined and bleached, with added leavening and salt; and enriched flour, refined and bleached, with added nutrients.
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cereal processingTreatment of flourAlthough such improvers and the bleaching agents used to rectify excessive yellowness in flour are permitted in most countries, the processes are not universal. Improvers include bromates, chlorine dioxide (in gaseous form), and azodicarbonamide. The most popular bleacher used is benzoyl peroxide.
Read MoreAlthough such improvers and the bleaching agents used to rectify excessive yellowness in flour are permitted in most countries, the processes are not universal. Improvers include bromates, chlorine dioxide (in gaseous form), and azodicarbonamide. The most popular bleacher used is benzoyl peroxide.
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