as flour improvers; their active fat-oxidizing enzymes, which generate the typical beany flavor, also indirectly cause the oxidation and elongation of gluten proteins The traditional air-aging of flour had a visible side effect: the yellowish flour becomes progressively paler as the xanthophyll pigments are oxidized to a colorless form Once the chemistry of this change was understood, millers began using bleaching agents (azodicarbonamide, peroxide) to whiten flours Many bakers prefer to use unbleached flours because they have been subjected to less chemical alteration Bleaching is not allowed in Europe Minor Flour Components The gluten proteins and starch granules in flour account for about 90% of flour weight, and for much of the behavior of flour doughs and batters But some minor components have an important influence Extraction Rates The degree to which a flour has been refined is designated by the “extraction rate,” or the percentage of the whole grain remaining in the finished flour Whole wheat flour has an extraction rate of 90% Most commercial white flours contain between 70 and 72% of the whole grain; French bread flour ranges from 72 to 78%, and so carries more flavor of the whole grain Home bakers can make their own higher-extraction refined flours by supplementing commercial white flour with a portion of whole wheat flour that they have sifted to remove coarse bran and germ particles Fats and Related Molecules Although white flour is only about 1% fats, fat fragments, and phospholipids by weight, these substances are ... wheat flour has an extraction rate of 90% Most commercial white flours contain between 70 and 72% of the whole grain; French bread flour ranges from 72 to 78%, and so carries more flavor of the whole grain...an important influence Extraction Rates The degree to which a flour has been refined is designated by the “extraction rate,” or the percentage of the whole grain remaining in the finished flour Whole... make their own higher-extraction refined flours by supplementing commercial white flour with a portion of whole wheat flour that they have sifted to remove coarse bran and germ particles Fats and