E503(ii) / Acidity regulators & anti-caking agents
Ammonium Bicarbonate
Safety in brief
Safe in moderation
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
Ammonium bicarbonate, also known as baker's ammonia or hartshorn, is a leavening agent used in crisp, flat baked goods like cookies and crackers. Unlike baking soda, it decomposes completely into gases (ammonia, carbon dioxide, and water vapor) during baking, leaving no salty aftertaste, though a temporary ammonia smell can occur if the product isn't baked thoroughly or is very thick.
Also appears on labels as: Ammonium bicarbonate, E503(i), E503(ii), E 503(ii), E-503(ii), INS 503(ii), ABC, Ammonium hydrogen carbonate, Carbonic acid, ammonium salt, Ammonium acid carbonate, NH4HCO3, Ammonium carbonate (basic).
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
- Generally recognized as safe at typical food levels once fully baked off.
- Can produce a strong ammonia odor during baking that may be irritating if inhaled directly in an enclosed space, though this dissipates as baking completes.
Country rules
Country checks for E503(II)
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 | No exact code match in the Annex II Part B list (version 2026-08-18, read 2026-10-07). Identity, subform and legal-use review are pending. This does not establish a permission or a ban. |
| Great Britain | No verified exact register record in this review. Identity and current use rules need checking; missing a record does not establish a ban. |
| United States | Complete current-use review pending. Any scoped provision in the label guide above applies only to the stated use. FDA explains the applicable food-additive and GRAS framework. |
| 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 2 listed food-use conditionsAmmonium BicarbonateHealth Canada: List of Permitted Acidity Regulators and Acid-Reacting Materials. List published ; item A.4.
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
- Original ingredient record
- No research links in the original record. 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 in moderation |
| WHO | Safe in moderation |
| EFSA | Safe in moderation |
| FSANZ | Safe in moderation |
| Japan | Safe in moderation |
| UK FSA | Safe in moderation |
| Health Canada | Safe in moderation |
Database updated: . What does an E number mean on a food label?
Common questions
Frequently asked questions
What is EatMatrix's recorded rating for E503(II)?
The recorded EatMatrix rating for E503(II) (Ammonium Bicarbonate) is “Safe in moderation”. 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 E503(II) vegan, halal or gluten-free?
According to our ingredient data for Ammonium Bicarbonate — 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 E503(II) and why is it used?
Ammonium bicarbonate, also known as baker's ammonia or hartshorn, is a leavening agent used in crisp, flat baked goods like cookies and crackers. Unlike baking soda, it decomposes completely into gases (ammonia, carbon dioxide, and water vapor) during baking, leaving no salty aftertaste, though a temporary ammonia smell can occur if the product isn't baked thoroughly or is very thick.
Does E503(II) contain allergens?
No known allergens are recorded for Ammonium Bicarbonate.
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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.