Carmoisine (Azorubine)
What it does
Red colour.
How it's made
Synthetic azo dye.
Carmoisine (also called azorubine) is a synthetic red azo colour used in products such as jellies, sweets, drinks and desserts, giving a bluish-red to maroon shade. It is water-soluble and stable, making it a versatile red for many foods.
It is manufactured by the standard azo-dye route from petroleum-derived aromatics. A sulphonated aromatic amine is diazotised with nitrous acid and coupled to a naphthol-based partner, forming the azo bond that produces the red colour, with sulphonic-acid groups giving water-solubility.
After synthesis the dye is purified and standardised, with limits on unreacted starting materials, and supplied as a red powder. As one of the azo colours permitted in the UK and EU, foods containing carmoisine must carry the warning about a possible effect on children's activity and attention.
Possible reactions
May trigger hyperactivity and reactions in asthmatics or aspirin-sensitive people.