• Initial Cleaning: Raw wheat kernels are passed through magnets to remove metal, and sieves or air currents to remove stones, dust, and plant debris.
• Conditioning (Tempering): Wheat is soaked in water for 6 to 24 hours. This toughens the outer bran (making it easier to peel) and mellows the inner endosperm (preparing it for grinding).?

• Breaking: Conditioned wheat passes through "break rolls"—corrugated steel rollers rotating at different speeds—which shear the kernels open to separate the white endosperm from the bran and germ.
• Sifting and Purification: The mixture is shaken through a series of vibrating sifters and bolting cloths with varying screen sizes. Purifiers use air currents to lift away remaining light bran fragments from the heavier endosperm particles (known as semolina).
• Reduction: The purified endosperm passes through smooth "reduction rolls" multiple times, gradually grinding it into a fine, white powder.?

• Chemical Agents: Gas (like chlorine) or powder (like benzoyl peroxide) is added to the fresh flour.
• Result: These agents oxidize carotenoid pigments (yellow) to make the flour stark white. This also alters the protein structure to improve dough elasticity, producing a finer crumb and higher rise in baked goods.?

• Nutrient Dosing: A precise dosing device measures out specific quantities of enrichment.
• Standard Additives: In the U.S., federal standards require the addition of?thiamine,?riboflavin,?niacin,?folic acid, and?iron.?

?

European Union has banned the use of chemical bleaching agents in flour altogether.

?

Enriched flour is far less common across Europe.

?

?

• Comprehensive Ban: The use of specific bleaching agents—including?chlorine dioxide,?benzoyl peroxide, and?azodicarbonamide (ADA)—has been prohibited in the EU since the 1990s.
• Standard for Import: Products made from chemically bleached flour are illegal to sell within the Union market.
• Labeling Changes: As of 2025–2026, many European regions (including the UK) have even prohibited the marketing term "unbleached flour" because the practice is so universally illegal that the term is considered redundant or misleading.?

• Carcinogenic Risks: Chemicals like potassium bromate and benzoyl peroxide have been linked to kidney and thyroid cancers in animal studies.
• Nutritional Degradation: Chemical bleaching destroys natural vitamins (such as Vitamin E and A) and alters the protein structure of the wheat.
• Cosmetic vs. Essential: Authorities emphasize that bleaching is primarily for appearance and does not justify the potential health risks, especially when safer natural aging alternatives exist.?