E132: Indigotine

What is E132?

Indigotine, also called indigo carmine and labelled E132, is a synthetic blue dye. Chemically, it is a sulphonated version of indigo, the pigment traditionally used to dye denim.

Origin and production

It is produced by chemical synthesis, typically by sulphonating synthetic indigo.

Why is it used?

Indigotine gives foods a blue colour and, combined with yellow colours, a range of greens. It is used in sweets, chocolate-coated candies, cake decorations, biscuits, snacks and some drinks.

Vegan, vegetarian and halal

Indigotine is synthetic and suitable for vegans and vegetarians. It is not generally a halal or kosher concern, although the colour may be supplied on an aluminium lake base.

Safety and regulation

Indigotine is authorised as a food colour in the EU and was re-evaluated by EFSA, which did not identify a risk of exceeding the acceptable daily intake. It is not one of the six 'Southampton' colours that require a warning label.

Common in