By Dylan Love
Egg yolks have long been criticized as unhealthy in comparison to their counterpart, the beloved egg white. Until recently, the assessment was that their high cholesterol content was cause to eliminate eggs from one’s diet. But new research and dietary guidelines are challenging the perception that cholesterol contributes to heart disease. So say farewell to egg-white omelettes — the yolk is where the good stuff lives.
In your grocery store’s egg section, you’re confronted with a wall of cartons and adjectives. After picking white or brown, how do you choose between organic, free-range, pastured, grass-fed, farm-fresh, cage-free, and omega-3 eggs? Without these labels, could you even tell the difference?
The answer is yes, but you have to crack them open to do so.
Whether you prefer sunny-side up or scrambled, you probably want to see a perfectly golden-yellow yolk. Egg yolk colors are almost completely dependent on the diet of the hen that laid it (unlike shell color, which depends on the hen’s breed.)
Hens that produce deeply saturated orange yolks eat a natural diet that might resemble your own: kale, collard greens, broccoli, brussel sprouts, and more. These yolks are especially rich in xanthophylls and carotenoids like lutein, loaded with nutrients, and even antioxidants. While there’s no guarantee, you’re more likely to find these yolks in eggs produced by hens raised in a pasture or free-range, where they have more opportunities to eat pigmented foods.
Orange or golden-yellow yolk
When your yolk color resembles that of a clementine, you have carotenoids to thank. The hen’s diet was made up of yellow and orange plant material, like yellow corn and alfalfa meal, which contain nutritious xanthophylls pigments that are deposited in the yolk. Not only that — their color might contribute to your brain enjoying them more.
Pale or light-yellow yolk
Pale yolks result from a colorless diet. If a hen eats feed made from wheat, barley, or white cornmeal, they may produce yolks that are almost white. Natural yellow coloring may be added to this type of feed to enhancethe yolks, turning them lemon-colored.
Red or pink yolk
Blood-orange, red, or pink yolks can come from hens that eat a lot of red pepper, but they are found most often in South America, where chickens feed on annatto seeds. And if you find just a speck of red in a yolk, it doesn’t mean the egg was actually fertilized. It’s simply a blood vessel that ruptured during formation. If the egg whites are pink, however, you ought to beware: your egg is rotting.
You have cooked your eggs. When left to boil a little too long, your yolks turns green as a result of iron in the boiling water interacting with the sulfur in the eggs. The good news? Green, like other colors, has no implications on the health benefits of an egg — sulfur is just another healthy nutrient found in yolks.
The crucial benefits of egg yolks are their macronutrients — like protein and healthy fats — which are relatively the same in all yolks, regardless of color. However, evidence is growing that pasture-raised hens produce healthier eggs that are higher in omega-3 fatty acids and vitamins A and E. So the next time you fry up an egg to start your day, look for a deep-orange yolk to really kick things off right!