Wheat flour is made from only the endosperm. Brown flour includes the germ and bran. Whole grain flour includes all three parts. Once each part has been separated, it is ground into a powder. White flour has a naturally yellow-ish color but is often bleached or mixed with oxidizing chemicals to produce a white color.

Wheat is classified by several different characteristics: the season it is grown (spring or winter wheat), its color, whether it is "hard" or "soft," by the amount of protein it contains, and by the amount of a specific protein, called gluten that it contains. Hard wheat is usually a bronze-color and has a higher gluten content than soft wheat, which is a light golden color.