In 1950, the Oleomargarine Act required prominent labeling of colored oleomargarine, to distinguish it from butter. In 1886, the first Oleomargarine Act which defined the essence of butter and imposed a two-cent per pound tax on oleomargarine, a butter substitute made from animal fat. The political clout of the dairy industry led to laws imposing prohibitions and limitations on the competing margarine product that remain in effect today.