You've probably seen or eaten a "farm-fresh" egg, with a gorgeous orange yolk, and wondered why it looks so different from standard grocery store eggs. Does that orange yolk mean it was a free-range egg or that there's something special about it? Does it make it more nutritious than regular eggs?
Where Egg Yolk Color Comes From
Turns out that egg yolk color is really just an indicator of the hen's diet! If they eat more yellow-orange carotenoids, or natural pigments, it affects and changes the yolk's color.
In fact, while artificial color additives are not allowed to be added to chicken feed, naturally pigmented substances like marigold flowers are sometimes added to feed to enhance yolk color.
What’s the big deal about orange yolks?
Besides being a coveted color, orange yolks are an indication of a well balanced and highly nutritious diet. A few things factor into the making of an orange yolk: xanthophylls, omega-3 fatty acids, and meats.
The Nutritional Value of Darker Yolks
As for the nutritional value of the yolks, darker, more colorful yolks have the same amount of protein and fat than lighter yolks. Some studies have shown, however, that eggs from pasture-raised hens can have more omega-3s and vitamins but less cholesterol due to healthier, more natural feed.
Despite the fact that there's no real proof that egg yolk color is related to flavor, some people still claim they find darker yolks more flavorful. Any noticeable difference in flavor, though, is probably again due to the hen's diet.