Potassium bisulfite

E number E228CAS 7773-03-7

Potassium bisulfite is a preservative and antioxidant used in wine, dried fruit and juices. Sulphites must be declared above ten parts per million because they trigger reactions in some asthmatics.

Where it is and isn’t permitted

Status of Potassium bisulfite 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 182.3616retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFANot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.

What it is made from

Produced by reacting sulfur dioxide with potassium carbonate. It is preferred to the sodium form in wine, where added sodium is unwanted.

  • Vegan
  • Vegetarian
CAS registry number
7773-03-7
InChIKey
DJEHXEMURTVAOE-UHFFFAOYSA-M
PubChem
CID 23663620

Every name it appears under

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

E number

  • E228

CAS registry number

  • 4429-42-9
  • 7773-03-7

As it appears in regulation

  • Potassium bisulfite

Other names

  • E 228
  • HSDB 1263
  • INS NO.228
  • INS-228
  • Kaliumbisulfit
  • Monopotassium sulfite
  • Potassium acid sulfite
  • POTASSIUM BISULFITE
  • POTASSIUM BISULFITE (II)
  • POTASSIUM BISULFITE (MART.)
  • POTASSIUM BISULFITE SOLUTION
  • POTASSIUM BISULPHITE
  • POTASSIUM BISULPHITE SOLUTION
  • Potassium hydrogen sulfite
  • Potassium hydrogen sulphite
  • potassium hydrogensulfite
  • Potassium sulfite (KHSO3)
  • Potassium sulfite, hydrogen
  • QJK5LO891P
  • Sulfite, potassium metabi-
  • Sulfurous acid, monopotassium salt
  • Sulfurous acid, potassium salt (1:1)

Systematic names

  • Potassium hydrogen sulfite

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

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

Machine-readable:/api/v1/additives/potassium-bisulfite.json