Aluminium ammonium sulfate

E number E523INS 523CAS 7784-25-0

Used as an acidity regulator — Codex also lists it as colour retention agent, firming agent, raising agent, stabilizer.

Aluminium ammonium sulfate, a form of alum, is a firming agent and raising-agent component. It is one of the additives that contributes dietary aluminium, which regulators assess separately from its function in food.

Where it is and isn’t permitted

Status of Aluminium ammonium sulfate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationNot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

7 food categories

highest permitted level 520 mg/kg

Show every food category
  • 04.2.2.3 Vegetables (including mushrooms and fungi, roots and tubers, pulses and legumes, and aloe vera), and seaweeds in vinegar, oil, brine, or soybean sauce — 520 mg/kg
  • 06.4.1 Fresh pastas and noodles and like products — 300 mg/kg
  • 07.1.2 Crackers, excluding sweet crackers — 100 mg/kg
  • 07.1.3 Other ordinary bakery products (e.g. bagels, pita, English muffins) — 100 mg/kg
  • 07.1.5 Steamed breads and buns — 40 mg/kg
  • 07.1.6 Mixes for bread and ordinary bakery wares — 40 mg/kg
  • 09.2.4.2 Cooked molluscs, crustaceans, and echinoderms — 200 mg/kg
CXS 192-1995 Table One, INS 523and 6 further provisionsretrieved 2026-09-07

What it is made from

Produced by crystallising aluminium sulfate with ammonium sulfate.

  • Vegan
  • Vegetarian
CAS registry number
7784-25-0
InChIKey
LCQXXBOSCBRNNT-UHFFFAOYSA-K
PubChem
CID 3032540

Every name it appears under

38 recorded names. A label may use any of them.

E number

  • E523

INS number

  • 523

CAS registry number

  • 7784-25-0

Other names

  • Alum, ammonium
  • Alum, ammonium anhydrous
  • ALUM, AMMONIUM, EXSICCATED
  • Aluminium ammonium bis(sulphate)
  • ALUMINIUM AMMONIUM SULFATE
  • Aluminium ammonium sulfate (1/1/2)
  • ALUMINIUM AMMONIUM SULFATE ANHYDROUS
  • Aluminium ammonium sulphate
  • aluminium(3+) ion ammonium disulfate
  • Aluminum ammonium alum
  • Aluminum ammonium bis(sulfate)
  • Aluminum ammonium disulfate (Al(NH4)(SO4)2)
  • ALUMINUM AMMONIUM SULFATE
  • Aluminum ammonium sulphate
  • aluminum sulfate ammonium salt
  • aluminum;azanium;disulfate
  • Ammonium alum
  • AMMONIUM ALUM ANHYDROUS
  • Ammonium alum; Ammonium aluminum alum; Ammonium aluminum sulfate
  • AMMONIUM ALUMINIUM SULFATE [WHO-DD]
  • Ammonium aluminum alum
  • Ammonium aluminum sulfate
  • AMMONIUM-ALUM
  • Caswell No. 041B
  • Curb
  • DPU64XYB1D
  • E 523
  • EPA Pesticide Chemical Code 098501
  • Exsiccated ammonium alum
  • HSDB 611
  • INS NO.523
  • INS-523
  • Monoammonium monoaluminum sulfate
  • SULFURIC ACID, ALUMINIUM AMMONIUM SALT (2:1:1)

Systematic names

  • aluminum azanium disulfate

Hazard reference values

No reference value for this substance in the sources we hold.

Evidence and how bodies read it

Studies, and the differing conclusions regulators drew from them, are curated by hand rather than machine-read, and none has been written for this substance yet.

Sources for this page

  • gsfa retrieved 2026-09-07

Full licence terms and publisher details on Sources. How this page is built and updated: Method.

Machine-readable:/api/v1/additives/aluminium-ammonium-sulfate.json