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Class: Natural
Ionisation: Acid

Chemical structure of Carmine

Common Name: Carmine
Suggested Name: Carmine
Other Names:

Cochineal Carminic acid

C.I. Number: 75470
C.I. Name: Natural red 4
Color: Red
Solubility Aqueous: Soluble
Solubility Ethanol: Soluble
Absorption Maximum: 500 (Merck) 495 (Aldrich)
Empirical Formula: C22H20O13
Formula Weight: 492.4


Carminic acid is the active colouring agent in both carmine and the less pure cochineal. It is rarely used in practice, however, since the considerably more easily obtained carmine is as effective in biological staining. Carmine is a valuable dye, which is invariably applied in conjunction with a mordant, usually aluminum. It can be used to stain glycogen (Best's carmine), acid mucopolysaccharides (mucicarmine), and nuclei (carmalum). Carmine is obtained from the bodies of the female of the insect Dactylopius coccus, also known as Coccus cacti.

Insect Dyes


  1. R. D. Lillie.
    Conn’s Biological Stains
    Williams & Wilkins, Baltimore, MD., U.S.A.
  2. Susan Budavari, Editor,
    The Merck Index, Ed. 12
    Merck & Co., Inc., Whitehouse Station, NJ, USA
  3. Aldrich chemical catalogue, 1992
    Aldrich Chemical Company, Milwaukee, WI, USA.