bran, outer coat of a cereal grain—e.g., wheat, rye, and corn—mechanically removed from commercial flour and meal by bolting or sifting. Wheat bran is extensively used as feed for farm animals. Bran is used as food for humans (in cereals or mixed with flour in bread) to add roughage (i.e., cellulose) to the diet. It is also used in dyeing and calico printing.

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 16percnt protein, 11percnt natural fibre, and 50percnt 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.

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