Having already attacked the quality of margarine, the dairy industry turned its focus towards the color. Butter has a natural yellow tint, depending on the animal’s diet. Butter manufacturers had long added color to their product to make its yellow hue consistent, and the public came to associate butter with this color. After margarine was introduced in 1874 as a substitute for butter, its producers sought to aggressively compete by copying the color
(margarine is naturally white).