Does McDonalds use any food color in their chicken nuggets to get the golden brown color? How do they ensure that all the pieces are of same color and would it be possible to replicate the same at home using a deep fryer?
It is not "food color" in the conventional sense. McDonald's techniques are based on something the 'home cook' can rarely achieve, consistency. Their friers are designed to maintain exactly the same temperature (375F, if I recall correctly). The typical home frier drops 20-30F as soon as food is added, the McMachines have the kind of heating elements that don't do that. The coating is milled and applied to create a consistent coating and they are cooked for EXACTLY the right amount of time, every time. It is interesting to actually sit and listen to what is going on in McKitchen, military drill teams lack the precision that McD's instills into their burger flippers.
You can also increase browning by adding some baking soda to the batter. This changes the alkalinity of the mixture and has a positive effect on the maillard reaction that causes food to brown and taste delicious.