21 U.S.C. § 321c

For the purposes of the Federal Food, Drug, and Cosmetic Act of June 26, 1938 , (ch. 675, sec. 1, 52 Stat. 1040 ) [ 21 U.S.C. 301 et seq.] nonfat dry milk is the product resulting from the removal of fat and water from milk, and contains the lactose, milk proteins, and milk minerals in the same relative proportions as in the fresh milk from which made. It contains not over 5 per centum by weight of moisture. The fat content is not over 1½ per centum by weight unless otherwise indicated. The term “milk”, when used herein, means sweet milk of cows.