The purple colored is contains more nutrients than the milk one for example the amount of calories in the purple is 116 while the milky has 112, the iron content in the purple is 6 percent while the milky has 4 percent, the amount, the protein, magnesium, and carbohydrate content varies also with purple variety having more. In addition I was taught that the deeper the color of food the more nutritive it will be and I have applied this when purchasing my food products.