A friend and I got to discussing eggs and that got me to wondering if chickens had been bred to select for eggshell coloration. I know of certain fowl that lay turquoise blue to olive green eggs, such as Araucanas and Pheasants, fowl that lay white eggs such as Leghorns, and fowl that lay brown eggs such as Orpingtons and Rhode Island Reds.
All the chicken eggs in our kitchen are brown. Why? Because that's the color that our farmer's Rhode Island Red hens lay. If they laid white eggs, we'd have eggs with white shells. I've used tens and tens of thousands of eggs in my life and one thing is clear, shell color makes no difference to the egg inside.
What matters for flavor is freshness and a fresh egg is a good egg, except for boiled eggs. The shells of fresh eggs do not want to release from the albumen, but that's the subject of another article.
I notice a reverse snob appeal to brown eggs that has developed over the past couple of decades. Factory eggs here in the US, all the rage in the 1950's and 60's, tend to be white because the birds that produce the most eggs the fastest (hence the cheapest) lay white eggs. In recent decades, people have come to associate factory eggs with all things big, bad, and industrial, hence the movement to brown eggs, which many people assume are somehow intrinsically better than white eggs.
I'll say it again that shell color has no bearing on the egg inside. Eggshell coloration is hereditary and comes from pigments deposited (or in the case of white eggshells, not deposited) onto the outer layers of the white shell.
Brown eggs are significantly more expensive than white eggs in US markets for two reasons. Chickens that lay brown eggs tend to be from larger breeds that require more feed and they tend to lay fewer, larger eggs. So it generally costs more to produce brown eggs than white. Coupling this real production expense with the misunderstanding that brown eggs are somehow better than white eggs lets producers command higher prices for brown eggs.
So again, buy your eggs based on freshness and not on shell color.
For a glimpse into the wide variety of eggshell coloration, from snow white to chocolate, with blue and pink thrown in for grins, see the following charts:
Henderson's Handy-Dandy Chicken Chart
Egg Shell Colour Chart by Breed of Hen