Veal simply refers to meat that comes from a cattle beast that is younger than the older cattle that beef comes from. There is no specific way to feed veal, but if the veal was fed a milk diet, then that is when the colour is lighter than when it is fed a more traditional diet.
Red, Pink and white veal. The colour of the meat is proportional to the amount of milk in their diet. The most sought after and expensive is white veal which has been exclusively fed on mothers milk.