What is E520?

Aluminium sulfate is a salt with the formula Al2(SO4)3. It is soluble in water and is mainly used as a coagulating agent in the purification of drinking water and wastewater treatment plants, and also in paper manufacturing. E520 sits in the E500–E599 series, which in the EU classification mainly covers acidity regulators and anti-caking agents.

What is E520 used for?

E520 belongs to the firming agents group. Firming agents keep fruit and vegetables firm when preserved.

Is E520 safe?

E520 is rated “moderate”. It is approved for use in food, but some people prefer to limit it. “Moderate” means it is approved, but is debated or something some people prefer to limit.

How E520 appears on labels

On food packaging you'll find E520 either as the number “E520” or by the name “Aluminium sulphate” 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 E520 vegan?

Yes, E520 is suitable for vegans.