What insect is the source of the red food dye carmine?

The insect that is the source of the red food dye carmine is the cochineal. The best-known species is Dactylopius coccus, a scale insect that lives on prickly-pear cacti.

Female cochineal insects contain carminic acid, a vivid red compound produced partly as a defense against predators. Harvesters collect and dry the insects, then extract the acid from their bodies. Processing it with aluminium or calcium salts produces carmine, also known as Natural Red 4 or E120 in food-labeling systems.

Cochineal dye has a long history in the Americas, where Indigenous peoples used it to color textiles before Spanish colonization. During the 16th century it became a major export and an important source of wealth for the Spanish Empire. Today it is still used in foods, cosmetics, medicines and biological stains.

Cochineal is sometimes confused with kermes, another scale insect used historically for red dye, or with lac insects, whose secretion produces shellac. Products containing carmine may be labeled “cochineal extract,” “carmine,” “carminic acid” or “E120.”