What is E538?

Calcium ferrocyanide is an inorganic compound with the formula Ca2[Fe(CN)6]. It is the Ca2+ salt of [Fe(CN)6]4-, ferrocyanide complex ion. E538 sits in the E500–E599 series, which in the EU classification mainly covers acidity regulators and anti-caking agents.

What is E538 used for?

E538 belongs to the anti-caking agents group. Anti-caking agents stop powders clumping, as in salt and spices.

Is E538 safe?

E538 is considered safe at the levels used in food and is approved for use in the EU. “Safe” means it is approved in the EU and regarded as safe at the levels used in food.

How E538 appears on labels

On food packaging you'll find E538 either as the number “E538” or by the name “Calcium ferrocyanide” in the ingredient list, often after its function. Ingredients are listed in descending order by weight, so an additive near the end is present only in small amounts.

Is E538 vegan?

Yes, E538 is suitable for vegans.