Potassium carbonate

E number E501INS 501(i)CAS 584-08-7

Used as an acidity regulator — Codex also lists it as stabilizer.

Potassium carbonate is an alkaline acidity regulator used in cocoa processing, noodle making and some traditional baked goods.

Where it is and isn’t permitted

Status of Potassium carbonate 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 184.1619retrieved 2026-09-07
Codex AlimentariusCodex Alimentarius Commission / JECFAPermitted, with conditions

16 food categories

highest permitted level 11,000 mg/kg

Show every food category
  • 01.1.2 Other Fluid Milk (plain) — GMP
  • 01.2.1.2 Fermented milks (plain), heat-treated after fermentation — GMP
  • 01.4.1 Pasteurized cream (plain) — GMP
  • 01.4.2 Sterilized and UHT creams, whipping and whipped creams, and reduced fat creams (plain) — GMP
  • 01.8.2 Dried whey and whey products, excluding whey cheeses — GMP
  • 04.2.2.7 Fermented vegetable (including mushrooms and fungi, roots and tubers, pulses and legumes, and aloe vera) and seaweed products, excluding fermented soybean products of food categories 06.8.6, 06.8.7, 12.9.1, — GMP
  • 06.4.1 Fresh pastas and noodles and like products — 11,000 mg/kg
  • 06.4.2 Dried pastas and noodles and like products — GMP
  • 09.2.2 Frozen battered fish, fish fillets and fish products, including molluscs, crustaceans, and echinoderms — GMP
  • 09.2.3 Frozen minced and creamed fish products, including molluscs, crustaceans, and echinoderms — GMP
  • 09.2.4 Cooked and/or fried fish and fish products, including molluscs, crustaceans, and echinoderms — GMP
  • 09.2.5 Smoked, dried, fermented, and/or salted fish and fish products, including molluscs, crustaceans, and echinoderms — GMP
  • 13.1.1 Infant formulae — 2,000 mg/kg
  • 13.1.2 Follow-up formulae — GMP
  • 13.1.3 Formulae for special medical purposes for infants — 2,000 mg/kg
  • 14.1.5 Coffee, coffee substitutes, tea, herbal infusions, and other hot cereal and grain beverages, excluding cocoa — GMP
CXS 192-1995 Table Three, INS 501(i)and 16 further provisionsretrieved 2026-09-07

What it is made from

Manufactured by reacting potassium hydroxide with carbon dioxide. Historically it was obtained by leaching wood ash, which is the origin of the word potash.

  • Vegan
  • Vegetarian
CAS registry number
584-08-7
InChIKey
BWHMMNNQKKPAPP-UHFFFAOYSA-L
PubChem
CID 11430

Every name it appears under

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

E number

  • E501

INS number

  • 501(i)

CAS registry number

  • 584-08-7

As it appears in regulation

  • Potassium carbonate

Other names

  • Alkaline Super Ionized Water
  • Bestmade Natural Products Kali Carb
  • BQN1B9B9HA
  • Carbonate of potash
  • Carbonic acid, dipotassium salt
  • Carbonic acid, potassium salt (1:2)
  • Caswell No. 685
  • CCRIS 7320
  • CLEANING-S
  • Dcad plus
  • Dipotassium cabonate
  • Dipotassium carbonate
  • E 501(i)
  • EPA Pesticide Chemical Code 073504
  • FACE-BODY-S
  • FOOD-S
  • Greenfish, Body-S
  • Greenfish, Cleaning-S
  • HSDB 1262
  • INS NO.501(I)
  • INS-501(I)
  • K-Gran
  • Kali Carb
  • Kali carbonicum
  • Kali carbonicum 200C
  • Kali Carbonicum Kit Refill
  • Kalium carbonicum
  • Kalium carbonicum 12 Special Order
  • Kalium carbonicum 6X
  • Kaliumcarbonat
  • MOONSTAR FACE AND BODY MIST
  • MOONSTAR HAIR MIST
  • NARO AMOR
  • NARO COMO
  • NARO QUINN
  • NARO TIAMO
  • Pearl ash
  • potasium cabonate
  • potasium carbonate
  • potasiumcarbonate
  • potassium cabonate
  • potassium carbon ate
  • potassium carbonat
  • Potassium carbonate
  • Potassium carbonate (2:1)
  • Potassium carbonate (K2(CO3))
  • Potassium carbonate (K2CO3)
  • Potassium carbonate, anhydrous
  • Potassium carbonate-13C
  • potassium-carbonate
  • potassiumcarbonat
  • potassiumcarbonate
  • Salt of tartar
  • SANITALK COMY-ANIMAL SANITIZER(COVID-19)
  • SANITALK GREEN-FRUIT,VEGETABLE
  • SANITALK-SANITIZER(COVID-19)
  • ZEROQ
  • ZEROQ FACE BODY
  • ZEROQ FOOD
  • ZEROQ PET

Systematic names

  • dipotassium;carbonate

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/potassium-carbonate.json