Why are there so many carotenoids?

What are carotenoids?

Carotenoids are a family of yellow, orange, and red pigments, synthesized by plants. First isolated from edible chanterelle mushrooms, carotenoids can be found in many plants, green algae, bacteria, and fungi. All carotenoids contain 40 carbon atoms, yet there are more than 750 naturally-occurring varieties. The xanthophylls (astaxanthin, lutein, zeaxanthin, many others) contain oxygen, whereas carotenes (α- and β-carotene) do not. Some carotenoids, such as α-carotene, β-carotene and β-cryptoxanthin serve as precursors to vitamin A (pro-vitamin A). In addition to serving a pro-vitamin A function, many carotenoids provide direct antioxidant properties (ex. Carophyll® Red canthaxanthin, ROVIMIX® β-carotene), or necessary pigment functions (ex. lutein, lycopene for support of vision). The most common carotenoids in the North America human diet are α-carotene, β-carotene, β-cryptoxanthin, lutein, zeaxanthin, and lycopene.

What are they used for?

In livestock diets, carotenoids are primarily used as pro-vitamin A sources plus antioxidants for various target tissues (ROVIMIX® β-carotene, Victus® Transition), as supplemental antioxidants (Carophyll® Red for breeder hens), or as highly-pigmented colorants for egg yolks, broiler skin and shanks, Carophyll®Red (Canthaxanthin), and Yellow (Apo-ester), and for salmon, Carophyll ®Pink (Astaxanthin). Egg yolks can contain yellow pigments from lutein, zeaxanthin and Apo-ester, orange from canthaxanthin, and reddish pigments from capsanthin, capsorubin, and citranaxanthin. Deposition from the hen to the egg favors Apo-ester (Carophyll® Yellow) and canthaxanthin (Carophyll® Red) over β-carotene, capsanthin, and lutein. Furthermore, zeaxanthin contributions from feed ingredients such as corn can vary from batch to batch, so that supplemental carotenoids must be included to manage desirable egg yolk color. Approved uses for supplemental carotenoids vary widely among global regions—consult the table below for approved uses in Canada and in the US. Other sources for poultry coloration include paprika (provides β-carotene, β-cryptoxanthin, zeaxanthin, capsorubin, capsanthin, and lutein), and marigold/Tagetes (provides zeaxanthin, lutein, other xanthophylls). Advantages of the purified, dsm-firmenich Carophyll sources over plant sources include predictability of response, purity, dispersibility, stability, and ability to adjust quickly to account for ingredient changes (ex. corn zeaxanthin).

Regulatory approvals for Carotenoids in Feeds in North America