Annatto dye (from seeds of the Bixa orellana tree)

The plant is cultivated precisely for the wonderful dye produced from the red papillae that cover the seeds. The seed contains 4.5–5.5% dye, which imparts a yellow to orange colour. The dye is obtained by soaking the seeds in hot water or oil. In Brazil, where the plant originates, the dye was used for body painting, wound healing, treatment of skin diseases and burns, and as a repellent. It was also frequently consumed as a remedy for treating diarrhoea, asthma, and as an antipyretic. Only later did it begin to be used to colour fabric and food products. The Aztecs knew the plant and its dye extremely well and called it 'achioti'.

Annatto is composed mainly of bixin and norbixin. Bixin, which is essentially the monomethyl ester of a dicarboxylic carotenoid, is oil-soluble, while norbixin, the dicarboxylic acid of the same carotenoid, is water-soluble. This means the dye can be produced on either a water or an oil basis.

The dye is used for colouring various products. It is most commonly found in margarines and cheeses, as well as in natural cosmetic products.

INCI: Bixa orellana