Lutein, a carotenoid, is a natural yellow food colouring obtained from the extraction of marigold flowers grown on commercial plantations. While lutein is only extracted from marigolds for colour, other sources such as kale and spinach contain high levels of lutein. Like other carotenes, lutein may provide health benefits due to its strong antioxidant properties.
Carotenoids benefit from certain processing strategies, such as incorporating antioxidants and specialized packaging.
Lutein is a long, conjugated carbon chain with cyclized end groups. The light absorption of the conjugated chain is responsible for the yellow colour. The long chain also leads to colour degradation due to oxidation and light. Lutein provides a yellow hue with good heat stability and also functions well over a wide pH range.
Lutein is naturally oil soluble, but it can be emulsified to produce a water dispersible liquid. It is permitted for food use in the European Union as a food colour additive, but lutein is not yet approved in the United States.