What is a “carotenoid”?
“Carotenoid” is the generic name for one of the most common groups of naturally occurring pigments found in the animal and plant kingdoms. To date, over 600 carotenoids have been identified in nature, varying in color from yellow to red. Most carotenoids are polyunsaturated hydrocarbons, containing 40 carbon atoms, and comprising two terminal ring systems. Carotenoids that are composed entirely of carbon and hydrogen are known as carotenes, while those that contain oxygen are termed xanthophylls. Carotenoids are the major pigmenting compounds and cannot typically be synthesized by fish.
