Brilliant Blue FCF
What it does
Blue colour.
How it's made
Synthetic dye from petroleum.
Brilliant blue FCF is a synthetic bright-blue colour used very widely in drinks, sweets, ice cream and many other products, and often combined with tartrazine to produce green shades. It is highly water-soluble and gives a vivid, clean blue.
It is a triarylmethane dye made by chemical synthesis from aromatic feedstocks. The process builds the central three-ringed structure and introduces sulphonic-acid groups that make the molecule water-soluble and fix the brilliant blue colour; the finished dye is then converted to its sodium salt.
The crude colour is purified and standardised, with limits on residual reactants, and supplied as a reddish-blue powder that dissolves to a bright blue. It is one of the most widely used blue food colours and is generally considered among the better-tolerated synthetic colours.
Possible reactions
Generally low risk; rare sensitivity.