Ammonium hydroxide

E number E527INS 527CAS 1336-21-6

Used as an acidity regulator.

Ammonium hydroxide is an alkaline processing aid used to adjust pH during manufacture, notably in caramel colour production and in some meat processing.

Where it is and isn’t permitted

Status of Ammonium hydroxide by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
United StatesFood and Drug AdministrationPermitted21 CFR 184.1139retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

1 food category

no numerical limit (good manufacturing practice)

CXS 192-1995 Table Three, INS 527and 1 further provisionretrieved 2026-09-07

What it is made from

A solution of ammonia gas in water. It is a processing aid rather than an ingredient and is normally neutralised or driven off.

  • Vegan
  • Vegetarian
CAS registry number
1336-21-6
InChIKey
VHUUQVKOLVNVRT-UHFFFAOYSA-N
PubChem
CID 14923

Every name it appears under

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

E number

  • E527

INS number

  • 527

CAS registry number

  • 1336-21-6

As it appears in regulation

  • Ammonium hydroxide

Other names

  • agua de amoniaco
  • AMINE HYDRATE
  • Ammonia (ammonium hydroxide) 28% by weight or more NH3
  • Ammonia aqueous
  • ammonia hydrate
  • Ammonia solution 25%
  • Ammonia water
  • Ammonia water (JP18)
  • Ammonia water 29%
  • Ammonia Water; Ammonia, Aqua; Ammonia, Monohydrate; Aqua AmmoniaSX 1; SX 1 (Ammonia Water);
  • Ammonia, aqua
  • Ammonia, monohydrate
  • ammoniaque
  • Ammonium aqueous (28% or less NH3)
  • ammonium hydorxide
  • ammonium hydoxide
  • Ammonium hydrate
  • ammonium hydroxid
  • Ammonium hydroxide
  • Ammonium hydroxide ((NH4)(OH))
  • Ammonium hydroxide (28% or less ammonia)
  • Ammonium hydroxide, 1N aqueous solution (+/-0.1N)
  • Ammonium hydroxide, 25% NH3
  • ammonium hyroxide
  • Ammoniumhydroxid
  • ammoniumhydroxide
  • amonium hydroxide
  • amrnonium hydroxide
  • Aqua ammonia
  • Aquammonia
  • Caswell No. 044
  • E 527
  • EPA Pesticide Chemical Code 005301
  • hidroxido de amonio
  • Household ammonia
  • HSDB 5125
  • Hydroxide, Ammonium
  • hydroxyde d'ammonium
  • NH3 water
  • Strong ammonia solution
  • SX 1 (ammonia water)
  • USP Solution Ammonia (Ammonium Hydroxide) TS Conforms to USP
  • VHUUQVKOLVNVRT-UHFFFAOYSA-N
  • water ammonia
  • water NH3

Systematic names

  • ammonium hydroxide

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

  • ecfr retrieved 2026-09-07
  • 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/ammonium-hydroxide.json