Canthaxanthin
What it does
Orange colour.
How it's made
Synthesised carotenoid.
Canthaxanthin is an orange-red carotenoid colour. In human food its permitted uses are limited (for example, certain sausage products), but it is well known for its use in animal feed, where it deepens the pink of farmed salmon and trout and the colour of egg yolks.
It occurs naturally in some mushrooms, crustaceans and fish, but the material used commercially is made by chemical synthesis to give a pure, consistent carotenoid identical to the natural pigment. The synthesis assembles the long carotenoid chain with the specific groups that produce the orange-red colour.
The pigment is purified and, being fat-soluble, formulated into oil suspensions or water-dispersible beadlets. Its use in human food is tightly restricted and its levels controlled, with most of its application being in fish and poultry feed rather than directly in foods eaten by people.
Possible reactions
Very high intake can deposit crystals in the retina.