✅ Safety Verdict: Completely Safe
E503 (Ammonium Bicarbonate) is completely safe. During baking, it breaks down entirely into ammonia gas, carbon dioxide, and water – all of which evaporate. No ammonium compound remains in the finished product. It's been used safely in baking for centuries.
💡 Don't Be Alarmed by "Ammonia"
The word "ammonia" sounds scary, but E503 is entirely safe:
- Ammonia is released as gas during baking – it doesn't stay in your food
- By the time you eat the biscuit, no ammonia remains
- This has been used in traditional baking since the 1800s
What is E503 (Ammonium Bicarbonate)?
E503 is Ammonium Bicarbonate (NH₄HCO₃), a traditional raising agent also known as:
- Baker's ammonia
- Hartshorn (historically made from deer antlers)
- Ammonium hydrogen carbonate
How it works:
- Decomposes when heated (above 40°C)
- Releases gases: ammonia (NH₃) + carbon dioxide (CO₂) + water (H₂O)
- Gases create bubbles – making baked goods rise and become light
- All gases escape during and after baking
Why it's used:
- Creates extra-crispy texture – better than baking powder for thin, crisp products
- No residue – unlike baking soda which can leave alkaline taste
- Fast-acting – releases gas quickly when heated
- Traditional recipes – some recipes specifically require it
Where is E503 Found?
Common Products:
- Biscuits – especially thin, crispy types
- Crackers
- Gingerbread and ginger biscuits
- Speculoos and similar spiced biscuits
- Flat breads
- Some cookies
Why Not Used in Cakes:
E503 works best for thin, flat products because:
- Ammonia gas needs to escape completely
- In thick products like cakes, gas can get trapped
- Trapped gas = ammonia smell (unpleasant but harmless)
The Chemistry (Simple Version)
When heated, E503 breaks down completely:
NH₄HCO₃ → NH₃ + CO₂ + H₂O
(solid) → (gas) + (gas) + (gas)
- 100% conversion – nothing solid remains
- All products are gases – they escape during baking
- Result: Light, crispy texture with no residue
Is E503 Safe?
✅ Safety Profile:
- No ADI needed – considered safe at any usage level
- No residue in food – completely decomposes
- Centuries of safe use – traditional ingredient
- Approved worldwide – EU, UK, US, etc.
What About the Ammonia Smell?
- Temporary: Fresh-from-oven products may have faint ammonia smell
- Harmless: The smell indicates gas is still escaping
- Disappears: Once cooled and aired, smell is completely gone
- Not in final product: Properly cooled products have no ammonia
E503 vs Baking Powder
Why use E503 when baking powder exists?
- Crispier results: E503 creates extra-crispy textures
- No residue: Baking soda can leave alkaline taste
- Traditional recipes: Some recipes don't work properly with substitutes
- Industrial efficiency: Works well in commercial baking
Regulatory Status
UK/EU: Approved with no ADI – quantum satis (as much as needed)
US: FDA approved, GRAS status
Status: Considered completely safe by all major authorities
Who Should Avoid E503?
Almost No One:
- E503 is safe for virtually everyone
- No allergies or sensitivities associated with it
- Safe during pregnancy
- Safe for children
The Only Consideration:
- If a product smells of ammonia, it may not be fully cooled/aired – wait for smell to dissipate or it's been stored improperly
The Bottom Line
- ✅ Completely safe – no residue remains in food
- ✅ Traditional ingredient – used for centuries
- ✅ Decomposes entirely into harmless gases
- ✅ Creates crispy texture – ideal for biscuits and crackers
- ✅ No allergies or sensitivities associated
- 💡 Ammonia smell is temporary and harmless
Our recommendation: E503 is one of the safest food additives. Don't be put off by the word "ammonia" – by the time you eat the product, no ammonia remains. It's a traditional, effective raising agent that creates deliciously crispy biscuits and crackers.
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Last updated: February 2026