bran

Edible broken seed coat, or protective outer layer, of wheat, rye, or other cereal grain, separated from the kernel. In flour processing, it is normally removed from the ground kernels by sifting them in a rotating, meshed, cylindrical frame; whole-grain flours retain the bran. Wheat bran, the most widely processed, contains 16% protein, 11% natural fibre, and 50% carbohydrate. Most bran is coarsely ground for stock feed. In a more refined form, it is used in breakfast cereal, breads, and muffins for its value to the human digestive system as roughage.

Find more information on bran. Upgrade to Britannica Online for more on bran.