| MadSci Network: Botany |
The yellow color is due to red, yellow or orange pigments called carotenoids. One well known carotenoid is beta-carotene, which is a precusor to vitamin A. There are hundreds of different carotenoids. Carotenoids are found in virtually all plant parts. Highly colored fruits and vegetables often contain high levels of carotenoids. Examples include apricots, carrots, tomatoes, peaches and corn. The main carotenoids in egg yolk are lutein and zeaxanthin. Plant leaves contain orange to yellow cartenoids that are masked by green chlorophyll. However, the chlorophyll of deciduous leaves degrades in the fall and reveals the yellow or orange carotenoids. Perdue chickens have a yellow skin because their diet includes marigold petals, which contain carotenoids. References Some Facts About Eggs Carotenoids Lutein Lutein and Zeaxanthin Perdue Chickens and Marigold Petals
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