Brown and white eggs are the same in terms of nutrition, taste and other cooking characteristics. The difference in the color of the egg shell is simply a matter or genetics. All eggs begin white, but as they travel through the later stages of the maturation process (shell development) brown egg laying hens deposit a pigment (protoporphyrin). This pigment tints the shells, but does not permeate into the eggs.
The general indicator, although there are exceptions, of egg color is that white eggs are most often laid by white or light coloured hens with white ear lobes. Brown eggs are most likely laid by brown, red or dark feathered chickens with red ear lobes. Turns out that the best indication of egg color can be determined from the color of a chicken’s ear lobes! .
Part of the Problem
Since there is a strong correlation between ear lobe color and feather color, feather color is often used as an indicator too. Darker colored chickens are generally larger breeds which require more feed to raise, thus their eggs are generally more expensive to purchase.