Potassium fumarate

CAS 7704-72-5

Listed as an acidity regulator and a nutrient supplement by Canada and the US.

Listed as acidity regulators (CA) · nutrient supplements (US)
Chemical structure of Potassium fumarate, from PubChem compound 6433511
Structure from PubChem CID 6433511 (National Library of Medicine, public domain). A depiction of one compound: where a listing covers a family, or a substance has no single structure, this page shows none.

The potassium salt of fumaric acid, used as an acidity regulator.

Where it is and isn’t permitted

Status of Potassium fumarate by jurisdiction. Every jurisdiction this site covers is listed, including those where the substance does not appear.
JurisdictionStatusScope and limitsCitation
Australia and New ZealandFood Standards Australia New ZealandPermitted, with conditions

54 food categories

no numerical limit (good manufacturing practice)

Show every food category
  • 0 Preparations of food additives — GMP
  • 1.1.1 Liquid milk (including buttermilk) — GMPOnly UHT goats milk.
  • 1.1.2 Liquid milk products and flavoured liquid milk — GMP
  • 1.2.2 Fermented milk products and rennetted milk products — GMP
  • 1.3 Condensed milk and evaporated milk — GMP
  • 1.4.1 Cream, reduced cream and light cream — GMPOnly UHT creams and creams receiving equivalent or greater heat treatments.
  • 1.4.2 Cream products (flavoured, whipped, thickened, sour cream etc) — GMP
  • 1.5 Dried milk, milk powder, cream powder — GMP
  • 1.6 Cheese and cheese products — GMP
  • 10.2 Liquid egg products — GMP
  • 10.3 Frozen egg products — GMP
  • 10.4 Dried or heat coagulated egg products — GMP
  • 11.1.1 Rainbow sugar — GMP
  • 11.3.1 Dried honey — GMP
  • 11.4 Tabletop sweeteners — GMP
  • 12.1.2 Reduced sodium salt mixture — GMP
  • 12.1.3 Salt substitute — GMP
  • 12.5 Yeast and yeast products — GMP
  • 12.6 Vegetable protein products — GMP
  • 13.3 Formulated meal replacements and formulated supplementary foods — GMP
  • 13.4 Formulated supplementary sports foods — GMP
  • 13.5 Food for special medical purposes — GMP
  • 14.1.1.2 Carbonated, mineralised and soda waters — GMP
  • 14.1.2.1 Fruit and vegetable juices — GMPFor juice separated by other than mechanical means only.
  • 14.1.2.2 Fruit and vegetable juice products — GMP
  • 14.1.3 Water based flavoured drinks — GMP
  • 14.1.4 Formulated Beverages — GMP
  • 14.1.5 Coffee, coffee substitutes, tea, herbal infusions and similar products — GMP
  • 14.2.3 Wine based drinks and reduced alcohol wines — GMP
  • 14.2.4.1 Fruit wine products and vegetable wine products — GMP
  • 14.2.5 Spirits and liqueurs — GMP
  • 14.3 Alcoholic beverages not included in item 14.2 — GMP
  • 2.1 Edible oils essentially free of water — GMP
  • 2.2.1.2 Butter products — GMP
  • 2.2.1.3 Margarine and similar products — GMP
  • 2.2.2 Oil emulsions (<80% oil) — GMP
  • 20 Foods not included in items 0 to 14 — GMP
  • 3 Ice cream and edible ices — GMP
  • 4.1.3 Fruits and vegetables that are peeled, cut, or both peeled and cut — GMP
  • 4.3 Processed fruits and vegetables — GMP
  • 5.1 Chocolate and cocoa products — GMP
  • 5.2 Sugar confectionery — GMP
  • 5.4 Icings and frostings — GMP
  • 6.3 Processed cereal and meal products — GMP
  • 6.4 Flour products (including noodles and pasta) — GMP
  • 7 Breads and bakery products — GMP
  • 8.2 Processed meat, poultry and game products in whole cuts or pieces — GMP
  • 8.3 Processed comminuted meat, poultry and game products, other than products listed in item 8.3.2 — GMP
  • 8.3.2 Sausage and sausage meat containing raw, unprocessed meat — GMP
  • 8.4 Edible casings — GMP
  • 8.5 Animal protein products — GMP
  • 9.2 Processed fish and fish products — GMP
  • 9.3 Semi preserved fish and fish products — GMP
  • 9.4 Fully preserved fish including canned fish products — GMP
Food Standards Code, Schedule 15, S15—5and 53 further provisionsretrieved 2026-10-17
CanadaHealth CanadaPermitted

no numerical limit (good manufacturing practice)

In: Unstandardized foods. Purpose: Acidity regulator. Limit: Good Manufacturing Practice.

Health Canada, List of Permitted Acidity Regulators and Acid-Reacting Materials (List 10), item P.8retrieved 2026-10-17
European UnionEuropean Commission / EFSANo listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it.
Great BritainFood Standards Agency / Food Standards ScotlandNo listed food uses foundThis site has not matched this substance to any food use on this jurisdiction’s list of authorised food additives. A food additive may be used only in foods that list names. Flavourings, enzymes, processing aids and added nutrients are regulated separately and do not appear on it.
JapanConsumer Affairs AgencyNo listing matchedThis site imports only Japan’s list of designated additives (Appended Table 1 to the Regulations for Enforcement of the Food Sanitation Act), matched by English name. Existing additives, natural flavouring agents and ordinary foods used as additives are permitted outside that list and are not imported, so an empty row does not show that Japan does not permit the substance.
South KoreaMinistry of Food and Drug SafetyNo listing matchedThis site imports Part III of South Korea’s Standards and Specifications for Food Additives, matched by CAS number, then INS number, then exact name. Mixed preparations and sanitisers are not imported, and an entry whose identifiers disagreed with a page’s is held for review, so an empty row does not show that South Korea does not permit the substance.
United StatesFood and Drug AdministrationPermitted, with conditions

Named in 21 CFR 172.350, which provides that fumaric acid and its calcium, ferrous, magnesium, potassium and sodium salts may be safely used in food under the stated conditions. The section is held on this site as the page fumaric-acid-and-salts-of-fumaric-acid; read it for the specifications and conditions.

21 CFR 172.350retrieved 2026-10-18
Codex AlimentariusCodex Alimentarius Commission / JECFANot listedDoes not appear on this jurisdiction’s permitted list. That is not the same as being prohibited.

How much is permitted

A listing usually limits the quantity as well as the food. Only one of the forms that takes is a figure: quantum satis and good manufacturing practice permit the amount the technological effect requires and no more, which is a limit rather than the absence of one. Figures below are the range across every food category this page is listed in, and categories differ between regulators — see how much is permitted.

Australia and New Zealand—54 GMP
Canada—1 GMP
United States—1 no quantity stated

No regulator sets a figure for Potassium fumarate. That is not an absence of control: where the listing says quantum satis or good manufacturing practice, the quantity is limited to what the effect requires.

What it is made from

Made by neutralising fumaric acid with a potassium source.

  • Vegan
  • Vegetarian

Compare other additives on the dietary indexes.

CAS registry number
7704-72-5
InChIKey
SHPKCSFVQGSAJU-SEPHDYHBSA-L
PubChem
CID 6433511

Every name it appears under

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

E number

  • E366

CAS registry number

  • 4151-35-3
  • 7704-72-5

Other names

  • 2-Butenedioic acid (E)-, dipotassium salt
  • 2-Butenedioic acid (E)-, potassium salt
  • 2-Butenedioic acid (Z)-, potassium salt
  • 2Butenedioic acid (E), potassium salt
  • Dipotassium fumarate
  • dipotassium;(E)-but-2-enedioate
  • Fumaric acid potassium(1:x)
  • Fumaric acid, potassium salt
  • potassium (E)-butenedioate
  • Potassium 2-butenedioate, (E)-
  • Potassium 2butenedioate, (E)
  • Potassium Fumarate

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 rather than machine-read, and none has been written for this substance yet.

Common questions

Assembled from what is above, in the words the questions are usually asked in. Each answer is the same statement the relevant section makes, with the same citations behind it.

What is Potassium fumarate?
The potassium salt of fumaric acid, used as an acidity regulator.
What is Potassium fumarate used for in food?
It is listed as an acidity regulator and a nutrient supplement — the role Canada and the US assign it. This page shows every function each regulator records, with the citation for each.
Is Potassium fumarate banned in Europe?
No. Potassium fumarate does not appear on the EU's list of authorised food additives, which is not the same as being banned: the EU permits an additive only where it has authorised it, and usually the reason for an absence is that no one applied. The EU has made no finding against this substance. It does mean it may not be used as a food additive in the EU today.
Where is Potassium fumarate permitted?
Of the seven regulators this site reads, Australia and New Zealand, Canada and the US permit it. Each permission is for named foods at named levels, not a blanket one; the table on this page gives them with citations.
Is Potassium fumarate vegan?
Yes. Potassium fumarate is not derived from animals, and is suitable for vegetarians. This page says what it is made from and how.

Sources for this page

  • anz retrieved 2026-10-17
  • ca retrieved 2026-10-17
  • us-listings retrieved 2026-10-18

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

Machine-readable: a JSON record of this additive is given on request —how to ask for access.

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