Brown vs. white eggs — is one more nutritious than the other? Are white eggs bleached? What is the difference between white and brown eggs? And why are organic eggs brown? These are just a few of the questions that are commonly asked by folks standing in front of a crowded case of eggs at the local grocery store. It used to be that you only had to choose the size of the eggs you wanted to buy. But now there are so many different choices, and so many different prices, it can be hard to decide which ones to purchase. Or for many of our readers, which ones to produce. Let’s unravel some of the mysteries — and misconceptions — about egg color.
First off, when it comes to white vs. brown eggs, the breed of the chicken is what determines the color of the egg. So, no — white eggs are not bleached. In fact, all eggs start as white eggs inside the chicken. It takes over 24 hours for an egg to be fully formed within the hen’s reproductive system, and it’s only during the very last step of the process that a pigment is sometimes deposited on the egg to determine its final color. The pigment protoporphyrin is responsible for the brown color and it is more or less “painted” on the outside of the white shell very late in the process of forming the shell. That’s why brown eggs are only brown on the outside of the shell but are white on the interior. In the case of the white eggs, there is just no pigment added at the end because that particular breed of chicken is genetically programmed to skip that last step. In the case of blue eggs, the pigment oocyanin is deposited on the egg earlier in the process, as it travels through the oviduct, and this pigment actually permeates the eggshell, making the egg blue on both the exterior and the interior of the shell. And then there are the “olive eggers” where the brown pigment overlays a blue egg, resulting in a green egg. The darker the brown pigment, the more olive the color of the egg will be.
Another interesting fact about brown vs white eggs is that the shade of the brown eggs will change as the egg-laying season progresses. The brown eggs will get lighter later in the season. This is because as the hen ages her eggs get bigger, but the amount of pigment that gets added at the end of the process stays the same. That means less pigment per surface area, resulting in a lighter brown color.
As far as nutrition goes, there are no major differences between eggs from different breeds of chickens; hence brown eggs are not necessarily higher in nutrition than white eggs. Since the nutritional content of the egg is formed long before the pigment is added, if the chickens are fed and raised in the same way, the color of the egg has no bearing on the nutrition found inside. But you might pay more for those brown vs white eggs! Why? “The brown egg layers need to have more nutrients and energy in their body to produce an egg than the white shell layers,” USDA research food technologist Deana Jones explained in a HuffPost story. “It takes more feed for a brown-shell egg layer to accommodate production of the egg.”
There is also a common misconception that all organic eggs are brown, or that if an egg is brown, it must be organic. That is simply not the case. Any egg can be organic if the chicken that produces it is fed only organic feed and is raised according to the guidelines of the National Organic Program (NOP). And although the hen itself may be healthier and happier under these NOP guidelines, the resulting egg is not necessarily more nutritious. The flavor may be stronger because the chicken is possibly eating a more varied diet including bugs and worms, but the flavor does not equate to nutrition. It is true that most of the organic eggs available in your grocery store case are brown, but this is probably more likely due to the fact that consumers think brown eggs are always organic and are more nutritious than that they actually are either of these things.
So what is the difference between white and brown eggs? You guessed it — just the color! And only the breed of the chicken that lays it determines the color of the egg. But there’s nothing wrong with wanting a little color in your life. I, myself, love to have a nice variety of egg colors from my hens if only because it just looks so nice to see all the different hues. So, when it comes to picking out the hens that you’ll have in your henhouse, you might decide that choosing your breeds partially based on what color of eggs they lay is a good idea.
There are many charts that will tell you what color of egg your hen will lay, but if you’re trying to answer the question, “Where do brown eggs come from?” you might not have to look any farther than the chicken’s earlobe. Yes, chickens have earlobes! While this isn’t a perfect predictor of the color of the egg that will be laid, it’s pretty accurate. Red earlobes generally mean the hen will lay brown eggs whereas white earlobes almost always predict white eggs. And some chickens, like the Araucana chicken breed, actually have earlobes that are pale green or blue in color and sure enough, their eggs are green or blue.
When deciding whether you want brown vs. white eggs, the choice is really just a matter of which color you like better.
Originally published in the April/May 2020 issue of Backyard Poultry and regularly vetted for accuracy.