E522 / Acidity regulators & anti-caking agents
Aluminum potassium sulfate
Safety in brief
Safe
Recorded EatMatrix rating, not a new clinical review. The amount, your sensitivities and country rules still matter.
- Watch for
- No allergen or sensitivity is recorded for this ingredient here. Check the whole product label; this is not an allergen-free guarantee.
- Our advice
- Read the whole food label and consider how often you eat the product. A name or E number does not tell you the amount, and an ingredient rating cannot assess the entire food.
What it is
Aluminum potassium sulfate (E522), also known as potassium alum, is used in food as a firming agent and in some pickled vegetables and baking powders. As with other aluminum-based additives, regulators have restricted its use due to concerns about cumulative dietary aluminum exposure.
Also appears on labels as: Aluminum potassium sulfate, Potassium aluminum sulfate, Potassium alum, Alum, Alum powder, Aluminum potassium alum, Food grade alum, Alum additive, Potash alum, E522, E 522, E-522.
Dietary information
- Vegan
- Yes
- Halal
- Yes
- Gluten-free
- Yes
- Allergens
- None recorded
Recorded ingredient information. Check the product label or certification: sources, other ingredients and cross-contact can vary.
Research & body effects
Health notes from our ingredient record
- EFSA has set a tolerable weekly intake for total dietary aluminum because high cumulative exposure has been linked to potential nervous-system and reproductive effects in animal studies.
- Contributes to overall aluminum intake alongside other aluminum additives, cookware, and some antacids/antiperspirants.
Other references from our ingredient record
These links come from the original ingredient record. They are separate from the source reviews above and have not all been checked for the exact ingredient, amount consumed or claim. Dates are shown newest first.
- Aluminum Potassium Sulfate Safety Profile: Food Additive Assessment — Food Safety Research Institute, Aluminum Safety in Food Applications Journal (2020). A safety evaluation of aluminum potassium sulfate (E522) examining its use as a food additive and firming agent. The research confirmed that aluminum potassium sulfate, when used according to approved regulations, maintains adequate safety margins. The study noted the importance of monitoring total aluminum intake from all sources, particularly for sensitive populations. The assessment supports continued use in specific food applications while emphasizing the need for careful exposure monitoring.[safe_in_moderation]
- Re‐evaluation of aluminium sulphates (E 520–523) and sodium aluminium phosphate (E 541) as food additives — EFSA Panel on Food Additives, EFSA Journal (2018). Official EFSA scientific opinion (bibliographic reference, imported 2026-10-13). It covers the additive as a group assessment and is not an individual human study; read the opinion for its findings.
Country rules
Country checks for E522
Permission depends on the market, type of food, amount and conditions. A scientific opinion or an E-number alone does not establish a legal use. These checks are separate from the stored EatMatrix rating.
Compare all eight markets and their sources
| Market | What is checked |
|---|---|
| European Union | Regulation (EC) 1333/2008, Annex II Part B, version , contains the exact code E522: Aluminium potassium sulphate. Listing alone does not allow every food use. Part E food categories, limits, specifications and applicable later acts still need a product-specific check. Source read: . |
| Great Britain | The FSA register record for E522 (Aluminium potassium sulphate) lists “Authorised” in England, Scotland and Wales. Register updated: 01 April 2025; record checked: . Food-specific conditions and specifications still need a separate legal check. |
| United States | Selected US conditions for Aluminum potassium sulfate Official federal text current through ; read . Food uses, limits and exceptionsNamed preparation and use conditions The named aluminum potassium sulfate is listed under good manufacturing practice. This is a food-grade, intended-use provision, not a permission for industrial alum or an unrestricted intake. EatMatrix’s reading: a legal use condition answers where and how an ingredient may be used. It is not a test of your product, a personal safe intake or a claim that the ingredient benefits your body. Match the named substance, food and amount. Other federal provisions, food standards, state rules and later changes may also apply; this is a selected source review, not a complete product-compliance decision. |
| Northern Ireland | Review pending. Check the applicable EU rules and territory arrangements; the GB register alone does not establish this status. FSA guidance is a starting source, not a verified permission for this entry. |
| Canada | Named food-use records located. Health Canada lists the preparations below for specified foods and purposes. This is conditional permission for those uses, not approval of every product or a personal safety verdict. Only the named records and conditions below were located. Exact composition and specifications still need matching. Source tables captured . List publication dates are shown separately. Good Manufacturing Practice (GMP) is a condition of use, not an unlimited amount or a recommended intake. Food and Drug Regulations B.16.003 requires the listed source, purpose, amount and other conditions to match. The official consolidation read was current to 21 September 2026; product specifications and applicable later changes still need checking. Read 5 listed food-use conditionsPotassium Aluminum SulphateHealth Canada: List of Permitted Firming Agents. List published ; item P.1.
Potassium Aluminum SulphateHealth Canada: List of Permitted Food Additives with Other Purposes of Use. List published ; item P.8.
Potassium Aluminum SulphateHealth Canada: List of Permitted Acidity Regulators and Acid-Reacting Materials. List published ; item P.3.
EatMatrix reading: match the exact preparation and food first. A manufacturing limit is not an acceptable daily intake (ADI). A label without the amount cannot establish exposure, and an unlisted name here does not establish a ban. |
| Australia | Review pending. Food Standards Code permissions and conditions need an additive-specific check. FSANZ food-additive rules is a starting source, not a verified permission for this entry. |
| New Zealand | Review pending. Food Standards Code permissions and conditions need an additive-specific check. FSANZ food-additive rules is a starting source, not a verified permission for this entry. |
| Japan | Review pending. The relevant list, identity and use standards need an additive-specific check. CAA food-additive lists is a starting source, not a verified permission for this entry. |
Sources & review status
Check what each source covers: an authority’s conclusion, a research finding and a country’s legal permission answer different questions.
What this guide covers
- Official assessment sources
- Commission-listed EFSA references for E522. Bibliographic identity checked; latest findings and current use rules need separate review.
- Original ingredient record
- 2 research links; newest recorded date: . Sources added separately to this guide are not included in this count.
This guide brings together our ingredient record and the dated sources shown here. Missing information describes a gap in this guide; it does not mean an ingredient is untested, safe or harmful. This is not a complete review of every study, preparation or current country rule. The amount in a product and how it is used still matter.
How to read the ratings, research and country checksAgency labels recorded by EatMatrix
These are imported database classifications, not verified current statements from each authority. Use the dated official sources below for their actual scope and conclusions.
| Authority | Database label |
|---|---|
| FDA | Safe |
| WHO | Safe |
| EFSA | Safe |
| FSANZ | Safe |
| Japan | Safe |
| UK FSA | Safe |
| Health Canada | Safe |
Official assessment sources for E522
The European Commission’s re-evaluation table lists official EFSA documents for this additive. Their identifiers and subjects were checked against publisher bibliographic records. A missing research link in the EatMatrix database does not mean the additive has never been assessed.
Name in the Commission table: Aluminium potassium sulphate.
- Re‐evaluation of aluminium sulphates (E 520–523) and sodium aluminium phosphate (E 541) as food additives
EFSA scientific opinion. Published: .
These are assessment references, including historical or group assessments. They do not establish the latest scientific conclusion, a human health benefit or risk, or current permission to use the additive in a particular food. Later assessments, corrections and food-use conditions need separate review. The recorded EatMatrix rating above is unchanged.
European Commission re-evaluation table, status as of . EatMatrix checked this bibliography on .
Database updated: . What does an E number mean on a food label?
Common questions
Frequently asked questions
What is EatMatrix's recorded rating for E522?
The recorded EatMatrix rating for E522 (Aluminum potassium sulfate) is “Safe”. It is calculated from labels stored in our ingredient database. These labels are not verified current regulator decisions or country permissions. A database update date is not a scientific review date.
Is E522 vegan, halal or gluten-free?
According to our ingredient data for Aluminum potassium sulfate — vegan: yes, vegetarian: yes, halal: yes, kosher: yes, gluten-free: yes, dairy-free: yes. Manufacturing sources can vary between products; check the label if it matters to you.
What is E522 and why is it used?
Aluminum potassium sulfate (E522), also known as potassium alum, is used in food as a firming agent and in some pickled vegetables and baking powders. As with other aluminum-based additives, regulators have restricted its use due to concerns about cumulative dietary aluminum exposure.
Does E522 contain allergens?
No known allergens are recorded for Aluminum potassium sulfate.
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This page shows information and classifications recorded in our ingredient database. Current scientific and market-specific verification remains pending as described above. It is general information, not medical advice.