What is "filled milk"

Filled milk is any milk, cream, or skim milk that has been reconstituted with fats, usually vegetable oils, from sources other than dairy cows. Pure evaporated filled milk is generally considered unsuitable for drinking because of its particular flavor, but is equivalent to unadulterated evaporated milk for baking and cooking purposes. Other filled milk products with substituted fat are used to make ice cream, sour cream, whipping cream, and half-and-half substitutes among other dairy products. Coconut oil filled milk became a popular cost-saving product sold throughout the United States in the early 20th century. Coconut oil could be cheaply imported, primarily from the Philippines (at the time under American rule), and this product was able to undercut the market for evaporated and condensed milk. At the time, liquid milk was not widely available or very popular because of the rarity of refrigeration and the problems of transportation and storage.