E523 · Aluminum ammonium sulfate
- WHO
- Safe
- FDA
- Safe
- EFSA
- Safe
- FSANZ
- Safe
- Japan
- Safe
- UK FSA
- Safe
- Health Canada
- Safe
What is E523?
Aluminum ammonium sulfate (ammonium alum) is a mineral salt sometimes used as an acidity regulator or firming agent in food, and historically in baking powder. Like other aluminum-based additives, it adds to overall dietary aluminum intake, which EFSA recommends limiting because high cumulative exposure has been linked to nervous-system and reproductive effects in animal studies. It is now uncommon in modern food products.
Also appears on labels as: Aluminum ammonium sulfate, Ammonium aluminum sulfate, Alum, Ammonium alum, Aluminum ammonium alum, E523, E 523, E-523, Food grade aluminum ammonium sulfate, Alum powder, Aluminum ammonium sulfate additive, Alum additive.
What the evidence says
- Contributes to total dietary aluminum exposure; EFSA has set a tolerable weekly intake for aluminum due to potential neurological and reproductive effects seen in animal studies.
- Not a significant concern from occasional or single-item exposure.
Frequently asked questions
Is E523 safe?
Our overall verdict for E523 (Aluminum ammonium sulfate) is “Safe”, based on the most cautious of the major regulators’ positions — FDA: safe; WHO: safe; EFSA: safe; FSANZ: safe; Japan: safe; UK FSA: safe; Health Canada: safe.
Is E523 vegan, halal or gluten-free?
According to our ingredient data for Aluminum ammonium sulfate — vegan: yes, vegetarian: yes, halal: yes, kosher: yes, gluten-free: yes, dairy-free: yes. Manufacturing sources can vary between products; check the label if it matters to you.
What is E523 and why is it used?
Aluminum ammonium sulfate (ammonium alum) is a mineral salt sometimes used as an acidity regulator or firming agent in food, and historically in baking powder. Like other aluminum-based additives, it adds to overall dietary aluminum intake, which EFSA recommends limiting because high cumulative exposure has been linked to nervous-system and reproductive effects in animal studies. It is now uncommon in modern food products.
Does E523 contain allergens?
No known allergens are recorded for Aluminum ammonium sulfate.
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This page summarises publicly available regulatory assessments and research. It is general information, not medical advice. Sources: EFSA, FDA, WHO and the studies linked above.