Doppio and Coffee Milk are produced all around the globe. And they change according to region in where they are cultivated. So, the question arises what is Doppio and Coffee Milk's differentiating factor?In following section we will take a close look at what is Doppio and Coffee Milk color, serving style, types and much more. First thing to know is what are the different types of Doppio and Coffee Milk. Well, Doppio types include Espresso while types of Coffee Milk are NA.