Enriched Flour - Flour Processing and Nutrient Loss

Flour Processing and Nutrient Loss

The conversion of grains to flour involves several steps that vary with the type of grain used. The initial stages of processing remove the bran and the germ of the seed. The bran is the outermost layer of grains that contains fiber (primarily insoluble), some protein, and trace minerals. The germ is the embryo of the seed that contains B vitamins and trace minerals. Because the germ has a fat content of 10%, it may reduce shelf-life. Thus, it is separated to ensure longer shelf life of the flour. In contrast to enriched flour, whole wheat flour contains both the bran and the germ. The remaining and largest portion of the seed is the endosperm. It acts as a nutrient reservoir for the developing embryo. The endosperm contains a large amount of carbohydrates, protein, iron, B vitamins (niacin and riboflavin), and soluble fiber.

Once the endosperm is isolated, it is ground into a fine powder and sifted to remove any remaining fragments of bran or germ. The final flour product contains a smaller portion of the original nutrients that were present in the seed prior to processing. Enrichment ensures that these important nutrients are restored to improve the quality of the flour.