Bixin is an

apocarotenoid Apocarotenoids are organic compounds which occur widely in living organisms. They are derived from carotenoids by oxidative cleavage, catalyzed by carotenoid oxygenases. Examples include the vitamin A retinoids retinal, retinoic acid, and retinol; ...

found in the seeds of the achiote tree (''Bixa orellana'') from which it derives its name. It is commonly extracted from the seeds to form

annatto Annatto ( or ) is an orange-red condiment and food coloring derived from the seeds of the achiote tree ('' Bixa orellana''), native to tropical America. It is often used to impart a yellow or orange color to foods, but sometimes also for its f ...

, a natural

food coloring Food coloring, or color additive, is any dye, pigment, or substance that imparts color when it is added to food or drink. They come in many forms consisting of liquids, powders, gels, and pastes. Food coloring is used in both commercial food ...

, containing about 5% pigments of which 70-80% are bixin.

Applications

: center, red seeds of the achiote tree : left, Bixin is one of the colorants used in the snack Cheetos. Several thousand tons are harvested annually.

Chemical properties

Bixin is unstable. It isomerizes into ''trans''-bixin (β-bixin), the double-bond isomer. : Trans-bixin

Bixin is soluble in fats and alcohols but insoluble in water. Upon exposure to alkali, the methyl

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides a ...

is hydrolyzed to produce the dicarboxylic acid norbixin, a water-soluble derivative. : norbixin structure

References

{{carotenoids Apocarotenoids E-number additives