Canthaxanthin is associated with E number E161g and is approved for use as a food coloring agent in different countries, including the United States[5] and the EU;[6] however, it is not approved for use in Australia and New Zealand.[7] It is generally authorized for feed applications in at least the following countries: US,[8] Canada,[9] EU.[10] In the EU, canthaxanthin is allowed by law to be added to trout feed, salmon feed and poultry feed.[11] The European Union limit is 80 mg/kg of feedstuffs,[4] 8 mg/kg in feed for egg laying hens and 25 mg/kg in feed for other poultry and salmonids.
Canthaxanthin is a potent lipid-soluble antioxidant.[12][13] The biological functions of canthaxanthin are related, at least in part, to its ability to function as an antioxidant (free radical scavenging/vitamin E sparing) in animal tissues.[14]
^Efficient Syntheses of the Keto-carotenoids Canthaxanthin, Astaxanthin, and Astacene. Seyoung Choi and Sangho Koo, J. Org. Chem., 2005, 70 (8), pages 3328–3331, doi:10.1021/jo050101l
^Surai, P.F. (2012). "The Antioxidant Properties of Canthaxanthin and Its Potential Effects in the Poultry Eggs and on Embryonic Development of the Chick, Part 1". World's Poultry Science Journal. 68 (3): 465–476. doi:10.1017/S0043933912000578. S2CID92297763.
^Surai, P.F. (2012). "The Antioxidant Properties of Canthaxanthin and Its Potential Effects in the Poultry Eggs and on Embryonic Development of the Chick, Part 2". World's Poultry Science Journal. 68 (4): 717–726. doi:10.1017/S0043933912000840. S2CID86113041.
^Surai, A.P.; Surai, P.F.; Steinberg, W.; Wakeman, W.G.; Speake, B.K.; Sparks, N.H.C. (2003). "Effect of canthaxanthin content of the maternal diet on the antioxidant system of the developing chick". British Poultry Science. 44 (4): 612–619. doi:10.1080/00071660310001616200. PMID14584852. S2CID42795189.