Potassium stearate

CAS 593-29-3

Listed as a stabiliser by Canada and the US.

Listed as stabilisers (CA, US) · preservatives (US) · thickeners (US) · formulation aids (US) · lubricants and release agents (US)
Chemical structure of Potassium stearate, from PubChem compound 23673840
Structure from PubChem CID 23673840 (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 stearic acid — a soap — used as an emulsifier, stabiliser and anti-caking agent.

Where it is and isn’t permitted

Status of Potassium stearate 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 ZealandNo 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.
CanadaHealth CanadaPermitted, with conditions

highest permitted level 2 %

2 permitted uses

Show every permitted use
  • In: Emulsifying preparations containing propylene glycol monoesters. Purpose: Stabilizing agent. Limit: 2.0%. — Health Canada, List of Permitted Emulsifying, Gelling, Stabilizing or Thickening Agents (List 4), item P.16
  • In: Chewing gum. Purpose: Plasticizing agent. Limit: Good Manufacturing Practice. — Health Canada, List of Permitted Food Additives with Other Purposes of Use (List 8), item P.13
Health Canadaand 1 further provisionretrieved 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

2 permitted uses

Show every permitted use
  • Named in 21 CFR 172.615(a) among the plasticizing materials (softeners) that chewing gum base may consist of, as "sodium and potassium stearates" complying with 21 CFR 172.863. The section is held on this site as the page chewing-gum-base; read it for the specifications and limitations. — 21 CFR 172.615
  • Named in 21 CFR 173.340(a)(2) among the substances that defoaming agents used in processing foods may consist of, as defined in 21 CFR 172.863. The section is held on this site as the page defoaming-agents; read it for the conditions. — 21 CFR 173.340
21 CFR 172.615and 1 further provisionretrieved 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.

Canada20,000 mg/kg1 numeric limit, 1 GMP
United States—2 no quantity stated

What it is made from

Made by neutralising stearic acid with potassium hydroxide. Stearic acid may be of vegetable or animal origin, which the listing does not settle.

CAS registry number
593-29-3
InChIKey
ANBFRLKBEIFNQU-UHFFFAOYSA-M
PubChem
CID 23673840

Every name it appears under

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

CAS registry number

  • 593-29-3

Other names

  • E-470(I)STEARIC ACID, POTASSIUM SALT
  • INS NO.470(I)STEARIC ACID, POTASSIUM SALT
  • INS-470(I)STEARIC ACID, POTASSIUM SALT
  • NONSOUL MK 2
  • Octadecanoic acid, potassium salt
  • Octadecanoic acid, potassium salt (1:1)
  • Octadecanoicacid,potassiumsalt
  • Potassium n-octadecanoate
  • Potassium octadecanoate
  • Potassium Stearate
  • Potassium stearate, pure
  • REXANOL
  • Steadan 300
  • Stearic acid, potassium salt

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 stearate?
The potassium salt of stearic acid — a soap — used as an emulsifier, stabiliser and anti-caking agent.
What is Potassium stearate used for in food?
It is listed as a stabiliser — the role Canada and the US assign it. This page shows every function each regulator records, with the citation for each.
Is Potassium stearate banned in Europe?
No. Potassium stearate 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 stearate permitted?
Of the seven regulators this site reads, 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.

Sources for this page

  • 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.

Follow changes to Potassium stearate:Atom feed — regulatory events, and any change the weekly refresh detects in its provisions.