Potassium Metabisulphite (E224) — What You Need to Know
What Is Potassium Metabisulphite?
Potassium metabisulphite is the potassium equivalent of sodium metabisulphite, widely used in winemaking and brewing as both a preservative and antioxidant. It releases sulphur dioxide (SO2) when dissolved in water, providing effective antimicrobial protection. It is often preferred over the sodium version in wine production due to the lower sodium content.
What Is It Used For?
Primarily used in winemaking and brewing to sterilize equipment, prevent oxidation, and inhibit wild yeast and bacterial growth. Also used in the preservation of dried fruits, cider, and fruit preparations.
Safety Assessment
Potassium equivalent of sodium metabisulphite. Commonly used in winemaking as both antioxidant and antimicrobial. Same group ADI and same sulphite sensitivity concerns. Often preferred over sodium version in wine production. EFSA 2016 assessment applies to all sulphites collectively.
Based on current evidence, Potassium Metabisulphite is rated Caution with a score of 5/10. This is 0.7 points below the average for preservatives (5.7/10). Last reviewed by regulators: 2016.
Commonly Found In
Always check the label for E224 or 'Potassium Metabisulphite'
▶Chemical Information
Frequently Asked Questions about Potassium Metabisulphite
Quick Facts
- E-Number
- E224
- INS Number
- 224
- Category
- Preservatives
- Origin
- Synthetic
- FDA Status
- GRAS
- EFSA Status
- Authorized — group ADI as SO2 for all sulphites (E220–E228)
- ADI
- 0.7 mg/kg bw/day
- Last Review
- 2016
Related Additives
Other preservatives in the same family