[L,. albus, white.] A nutritive substance found in animals; also a supply of nourishing matter within the integuments of the seed in many plants, external to the embryo or germ in some, and within it in others. It is the floury part in wheat and other grains, and is a very important part of food. Albumen exists in many of the solids and fluids of the animal body, also in many plants. It occurs in its purest form in the white of an egg, and in the serous or liquid portion of the blood. It is a yellowish, transparent, gum-like substance, soluble in cold water. One of the most characteristic properties of a solution of albumen is its power of coagulation. If a solution be heated to about 700, it becomes solid and opaque, and in this state it is insoluble in water, but dissolves in dilute alkalies.