Sunday, March 3, 2013

Influencing Egg Yolk Color

Egg yolks range in color from pale yellow to a deep orange yellow in color.  In this article, we'll describe what determines egg yolk color and how backyard chicken keepers can influence the yolk color of their laying flocks with natural food supplements.

The Chemistry of Egg Color

Egg color is a function of the chickens diet.  Specifically, the amount and type of carotenoids the chicken consumes.  Carotenoids are organic pigments found in plants, algae and some bacteria. Their color ranges from pale yellow, through bright orange to red.  Lutein and zeaxanthin caretonoids are yellow in color. Common natural sources of these include corn, alfalfa and leafy green vegetables like kale and spinach. Citranaxanthin, lycopene and capsanthin carotenoids are red in color. Common natural sources of these include tomatoes, chillies and red peppers. 

When consumed by chickens, these carotenoids impact the color of the chickens skin and also the color of the chicken's egg yolks.  So diets that differ in the mixture of these various carotenoids will produce a range of yolk colors. For example, diet that is high in wheat will produce eggs that are very pale because they are lower in yellow carotenoids (specifically zeaxanthin) than a diet that is rich in corn or other ingredients that are high in yellow carotenoids.




Does Egg Color Matter?

Yes, and no.  From the perspective of nutrition, yolk color is not an indicator of the protein, carbohydrate or other macro-nutrient levels in eggs. So egg yolk color doesn't matter if all you consider is the eggs nutritional value. 

However, food color does impact our enjoyment of food. Importantly, our perception of food quality is also greatly influenced by its color. 

In the United States, most consumers prefer bright yellow eggs to pale ones and the commercial egg industry is well aware of this.  Egg yolk color is monitored and, in some cases, the chickens are fed supplements in order to change the color of the yolks to make them more palatable. For example, the chemical company BASF sells Lucantin(R) red and Lucantin(R) yellow to shift the color of the eggs to make them more yellow or more orange respectively.


A Roche Color Yolk Fan Provides Commercial Egg Farmers with A Way of Accurately
Measuring Egg Yolk Color

Backyard Flocks - Yellow With Envy

If you feed your flock a commercial feed pellet, the color of the your flock's eggs will be fairly consistent throughout the year.  Eggs from birds that free-range will show a greater range in egg color based on the plants and bugs they consume during any given season and the degree to which they are supplementing their diet.

If your birds consume primarily commercial feed, it's possible to change the color of their yolks using the same strategy as commercial producers but without the chemicals.
You can do this by supplementing your flocks normal diet with natural foods that are high in various carotenoids.
If you like deep yellow eggs, provide your flock with lots of leafy greens or marigold petals.  For example, kale is a staple in our winter garden and we definitely notice a change in egg color when our girls are getting kale scraps. If you prefer darker eggs that are orange-colored, give your chickens carrot peels, less-than-perfect tomatoes, and peppers.

Article sponsored by ChickenWaterer.com, makers of the BriteTap chicken waterer. The BriteTap waterer keeps your chicken's water completely clean. No poop-filled pans of water to clean.





3 comments:

  1. We've been looking for a water system that fits our needs and this one looks and sounds like we hit pay dirt!

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  2. I can indeed verify that chickens that eat tomatoes and red peppers will give you eggs with very red-orange yolks. They love the very hot peppers too, especially the seeds, but they eat the whole thing. We also give the chickens lots of kale. We grow a whole row of perennial kale just for them.

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  3. huh, my chickens will not eat peppers, or onions for that matter. they will only eat the seeds from them. the yolk will get a slight red color to them if the birds get into alot of tomatoes.

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