Why Are Eggs Blue?

The Urban Chickens - Blue Eggshells - Brown Eggshells

The insides of Blue and Brown Eggshells

The Urban Chickens - Ameraucana Eggs

Ameraucana Eggs


A Rainbow of Eggs

The Urban Chickens - Blue Eggs in Nest Box

Blue Eggs in the Nest Box

The Urban Chickens - Blue Ameraucana Eggs

Blue Ameraucana Eggs

How Do Eggs Get Their Color?

How is it that some eggs are incredible shades of blue, some are a gorgeous chocolate brown or even speckled, and some are white?

Although feather and ear color of a hen can play a small part in indicating egg color this is not consistent across all breeds. Many white feathered and white ear hens will lay white eggs; most red-brown feathered and red ear hens will lay brown eggs—however, there is a huge variation of exceptions across breeds. So, feather and ear color might help you guess egg color to win a bet, but it may or may not correspond in reality. More so, this is an interesting tidbit of trivia! Genetics and variations during the egg laying process are what determines egg color.

Blue Eggs

Chickens that lay blue eggs carry the blue egg gene. Araucanas, Ameraucanas, and Easter Eggers, all carry the blue egg laying gene. Blue eggs are blue all the way through and through due to oocyanin or billiverdin (the scientific name), a component in chicken blood, being deposited on the eggshell as it is developing in the uterus. Blue eggs are truly blue inside and out—consistently throughout the entire eggshell.

Brown Eggs

Brown eggs actually start out white, with a brown “dye” painted onto the egg during the final 4-6 hours before laying. The process of just the egg formation takes about 20 hours, for a grand total of 24-26 hours to create just one egg!

Amazing fact: Brown eggs retain their white insides! Variations of brown eggs range from a pale light brown to the deepest ruddiest chocolate brown that you’d think the Easter Bunny left a chocolate egg! And some even have unique speckle patterns and spots.

Rhode Island Reds, Gold Sex Links, Black Australorps, Buff Orpingtons, Cuckoo Marans and Welsummers are some breeds of chickens that lay brown eggs.

Brown eggs can generally cost more at the supermarket, mostly because of the illusion they are more healthful due to their natural brown color and then partly because brown eggs are usually extra-large to extra-extra large in size compared to some white eggs.

White Eggs

Eggs with white shells are white due to the calcium carbonate content of the egg shell. Eggshells are made up of 95%+ calcium carbonate, with a protein matrix substance holding it all together.

Nutritional Value of Eggs

An interesting thing to consider is that brown eggs or blue eggs or white eggs are not more healthy or packed with nutrition than any other color of egg—they are all equal nutritionally.

However, that being said, free range chicken eggs have higher Omega 3s and lower cholesterol and bright, deeply-colored orange-yellow yolks, so it is how the chicken is raised and what the chicken eats that affects the nutrition of the egg—egg color is just for looks! For healthier eggs, choose free range chickens eggs from chickens that enjoy their lives outdoors eating bugs and greens—happy chickens equals healthy food!

Pretty neat stuff!!! And pretty eggs too! :)

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