Sodium Sulphite (E221) — What You Need to Know
What Is Sodium Sulphite?
Sodium sulphite is an inorganic compound used as a preservative and antioxidant in the food industry. It releases sulphur dioxide (SO2) in solution, which is the active antimicrobial and antioxidant agent. It is part of the sulphite group of preservatives (E220–E228) that have been used in food preservation for centuries.
What Is It Used For?
Used to prevent browning and microbial spoilage in dried fruits, wines, and dehydrated vegetables. Acts as both an antioxidant and antimicrobial agent, and is also used as a bleaching agent in some food processing applications.
Safety Assessment
Part of the sulphite group (E220–E228). Sulphites can trigger severe asthmatic reactions in sulphite-sensitive individuals (estimated 3-10% of asthmatic patients). FDA mandates labeling when sulphites exceed 10 ppm. Sulphites destroy vitamin B1 (thiamine). EFSA lowered the group ADI from 0.7 to 0.7 mg SO2/kg bw/day in 2016 after finding exposure frequently exceeded ADI.
Based on current evidence, Sodium Sulphite 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 E221 or 'Sodium Sulphite'
▶Chemical Information
Frequently Asked Questions about Sodium Sulphite
Quick Facts
- E-Number
- E221
- INS Number
- 221
- Category
- Preservatives
- Origin
- Synthetic
- FDA Status
- GRAS (with mandatory labeling above 10 ppm)
- 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