What Is Carmine?
Carmine is a shiny, columnar crystal with a pomegranate-red color, known as an anthraquinone skeletal compound and the main component of cochineal extract. It is resistant to heat, light, and fermentation and is extracted from cochineal insects found in Central and South American deserts.
Uses of Carmine
Carmine is used as a coloring agent in various foods and as an ingredient in flavoring, paints, color photography, and bacterial staining. It forms complexes with aluminum and calcium ions to create deep reddish lake pigments and is used in cosmetics for red coloring.
Properties of Carmine
Carmine is soluble in water, ethanol, ether, concentrated sulfuric acid, and alkaline hydroxide solutions, but insoluble in petroleum ether, benzene, and chloroform. Its color changes with pH, and it decomposes at 135°C with a pKa of 1.59 ± 0.20.
Structure of Carmine
Carmine has an anthraquinone structure linked to a glucose unit, with a chemical formula of C22H20O13 and a molar mass of 492.38 g/mol. It is extracted from various insects and used as a natural dye and food additive.
Other Information on Carmine
1. Carminic Acid in Nature
Carmine is a naturally occurring red glucosidic hydroxyanthraquinone found in scale insects. It is synthesized by these insects for defense against predators and was traditionally extracted from the European Kermes beetle.
2. Related Compounds of Carmine
The nucleus of carmine is composed of the anthraquinone structure, which are aromatic organic compounds derived from anthracene. Anthraquinone, also known as anthracene-9,10-dione, is a yellow to light gray crystalline powder.