Photo courtesy of Homegrown on a Hobby Farm
Until relatively recently, chicken eggs were on the naughty list of many dietitians for the levels of cholesterol contained within their yolks. According to the Mayo Clinic, the effect of egg consumption on blood cholesterol is minimal, especially in comparison to the effect of trans and saturated fats on blood cholesterol. Basically, eggs are not the bad guy here—they are not likely to increase the risk of heart disease for healthy individuals when consumed in moderation (about 7 eggs per week). If cholesterol is a particular health concern, egg whites contain none, so knock yourself out with egg white omelettes!
For those of us who do consume the yolks, and like to watch stuff like this:
What does the color and consistency of the yolk mean? Does it have any effect on the nutritional quality of the egg?
…and Egg Quality
Let’s set the record straight here: Yolk color has no relationship to egg quality, flavor, nutritive value, cooking characteristics or shell thickness, according to The American Egg Board. The macronutrient composition of darker-colored and lighter-colored eggs is identical, however there may be some very minor differences in micronutrient concentrations like vitamin A and lutein. All in all, an egg’s an egg.
…What does it mean?
Egg yolks range in color from pale yellow to deep orange. The color of an egg’s yolk depends solely upon the hen’s diet. The darker color of a yolk signals the presence of carotenoids, which are natural pigments found in some plants. The availability of carotenoid-rich plants for chickens’ consumption affects the “orangeness” that you see in their eggs yolks. Keep in mind that chickens should be fed an omnivorous diet with insect and animal proteins as well as vegetable and grain-based ingredients, but the presence of carotenoids in hens’ diets is the main determinant of color.
The Spectrum of Yolk Color
Since carotenoid-rich fodder is more common and available in “Pasture Raised” operations, eggs from these chickens are more likely to be deeper orange in color. However, any chicken egg can turn out orange, not just pasture raised ones. As long as chicken feed contains the nutrients that trigger orangeness, the yolk will turn out this deeper color.
Mid-orange to golden yellow
Hen diets heavy in green plants, yellow corn, alfalfa and other plant material with xanthophylls pigment (a yellow-orange hue) will produce a darker yellow-orange yolk, according to Food & Nutrition Magazine. This is the most common color yolk we see in eggs available at the grocery store.
Diets lower in xanthophylls, such as feeding regimens that consist of mostly wheat, white cornmeal or barley produce pale yellow yolks.
If you’ve ever hard-boiled or scrambled eggs just a little bit too long and noticed an off-putting green color, don’t worry—that’s just a result of sulfur and iron compounds in the egg reacting with the surface of the yolk. If you want to avoid the greenish tint, make sure you follow the appropriate cook time and temperature. Specifically for hard-boiled eggs, rapidly cool them after cooking by placing in a bowl of ice water to further safeguard against greenness.
What about shell color?
You may have noticed that brown eggs are slightly more expensive than white eggs. If you were fooled like I was, you might think that brown eggs are somehow more “natural,” which would explain the higher price tag. You maybe sprung for the brown eggs because of this without thinking twice.
The truth is, shell color depends entirely upon the breed and color of the hen that lays the eggs. Among commercial breeds, hens with white feathers and earlobes lay white-shelled eggs; hens with red feathers and earlobes lay brown eggs. Some hens even lay green and blue eggs!
So, why the difference in price? Rhode Island Red, New Hampshire and Plymouth Rock breeds are red chickens that lay brown eggs. These breeds of hen are slightly larger birds, therefore they require more food, so that’s more money spent by farmers keeping their chickens full and healthy. The cost of raising larger chickens causes the price of brown eggs to be slightly higher in price.
I hope this post clears up some of your misconceptions about egg yolks. Keep in mind that there is no relationship between yolk color and the taste and nutritive value of eggs.
However, color is the spice of life, so be adventurous and diverse with your egg choices! In my opinion, it’s better to experience the full spectrum than an egg-monotone.