Acidity Regulators — Complete E-Number Guide
Acidity Regulators are food additives (E500–E599) that control the acidity or alkalinity of food. They are found in many everyday foods including baked goods, soft drinks, sweets, dairy products and processed foods. This guide covers every acidity regulator E-number with its safety, vegan and halal status at a glance.
| E-Number | Name | Safety | Vegan | Halal |
|---|---|---|---|---|
| E507 | Hydrochloric Acid | Safe | Yes | Halal |
| E508 | Potassium Chloride | Safe | Yes | Halal |
| E509 | Calcium Chloride | Safe | Yes | Halal |
| E511 | Magnesium Chloride | Safe | Yes | Halal |
| E513 | Sulphuric Acid | Safe | Yes | Halal |
| E514 | Sodium Sulphates | Safe | Yes | Halal |
| E515 | Potassium Sulphates | Safe | Yes | Halal |
| E516 | Calcium Sulphate | Safe | Yes | Halal |
| E517 | Ammonium Sulphate | Safe | Yes | Halal |
| E520 | Aluminium Sulphate | Some Concerns | Yes | Halal |
| E521 | Aluminium Sodium Sulphate | Some Concerns | Yes | Halal |
| E522 | Aluminium Potassium Sulphate | Some Concerns | Yes | Halal |
| E523 | Aluminium Ammonium Sulphate | Some Concerns | Yes | Halal |
| E524 | Sodium Hydroxide | Safe | Yes | Halal |
| E525 | Potassium Hydroxide | Safe | Yes | Halal |
| E526 | Calcium Hydroxide | Safe | Yes | Halal |
| E527 | Ammonium Hydroxide | Safe | Yes | Halal |
| E528 | Magnesium Hydroxide | Safe | Yes | Halal |
| E529 | Calcium Oxide | Safe | Yes | Halal |
| E574 | Gluconic Acid | Safe | Yes | Halal |
| E576 | Sodium Gluconate | Safe | Yes | Halal |
| E577 | Potassium Gluconate | Safe | Yes | Halal |
| E578 | Calcium Gluconate | Safe | Yes | Halal |
| E579 | Ferrous Gluconate | Safe | Yes | Halal |
| E585 | Ferrous Lactate | Safe | Uncertain | Halal |
What do acidity regulators do?
Additives in the acidity regulators group control the acidity or alkalinity of food. Without them, many everyday products would spoil faster, separate, lose texture or look unappetising — which is why they appear in so many ingredients lists. Every additive in this table has been through EFSA's authorisation process, but as the safety column shows, "authorised" doesn't always mean "concern-free": some carry conditions, warnings or ongoing debates, and each entry links to a full breakdown.
Checking labels for acidity regulators
On UK and EU labels these additives appear with their function and E-number or name — for example "acidity regulator: E507". Tap any E-number in the table for its complete profile: what it is, where it's found, whether it's safe, and its vegan, vegetarian, halal and palm-oil status.
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Additive data sourced from Open Food Facts (ODbL licence) and the European Food Safety Authority (EFSA).