E220 - Sulphur dioxide

At a glance

• What it is: A colorless gas (often used as a dissolved “sulfite” solution) that preserves food and prevents browning.
• What it does: Acts as an antioxidant and antimicrobial agent, and helps keep color and flavor.
• Where it’s found: Wines and ciders, dried fruits, fruit juices, jams, pickled foods, and some seafood.
• How it appears on labels: “Sulphur dioxide,” “sulfur dioxide,” or E220; related sulfites include sodium metabisulphite (E223) and potassium metabisulphite (E224).
• Who should be careful: People with sulfite sensitivity, including some individuals with asthma.

Why is Sulphur dioxide added to food?

Sulphur dioxide protects food quality in several ways. It prevents oxidation (a reaction with oxygen) that can dull flavors and cause browning, and it also suppresses the growth of certain microbes that spoil food and drink.¹

In winemaking and fruit processing, it helps keep the color bright and the taste clean by slowing browning enzymes and limiting oxidation during storage.¹

What foods contain Sulphur dioxide?

You’ll commonly see it in:

• Wine and cider
• Dried fruits (such as apricots, apples, raisins)
• Fruit juices and concentrates
• Jams, jellies, and preserves
• Pickled vegetables and relishes
• Some seafood (for example, shrimp)
• Some doughs and starch-based products

In the United States, sulphur dioxide is not allowed on raw fruits and vegetables that are meant to be served fresh, and it is not permitted in meats.²

What can replace Sulphur dioxide?

The best substitute depends on the job it’s doing:

• To prevent browning and oxidation in fruits and drinks: ascorbic acid (vitamin C), citric acid, or natural antioxidants like tocopherol-rich extract.
• To control spoilage microbes in juices and wines: dimethyl dicarbonate in beverages, or careful pasteurization and airtight/oxygen-limiting packaging.
• To preserve acidity-appropriate foods: sorbic acid and potassium sorbate, or benzoic acid and sodium benzoate, where allowed.
• In cheeses and surface treatments: natamycin, where permitted.

Each option has its own taste impact and legal limits, so food makers choose based on the product and local rules.

How is Sulphur dioxide made?

Commercially, sulphur dioxide is produced by burning elemental sulfur in air or oxygen, or by roasting metal sulfide ores. The gas can then be dissolved in water to make solutions used in food processing.³

Is Sulphur dioxide safe to eat?

Safety depends on the amount. In the European Union, experts set a group Acceptable Daily Intake (ADI)—the estimated daily amount considered safe over a lifetime—of 0.7 mg per kilogram of body weight per day, expressed as sulphur dioxide equivalents (covering E220–E228). Some consumers, especially high users of certain foods, may exceed this level.¹

In the United States, sulphur dioxide is permitted for specific uses, but it is not allowed on raw fruits and vegetables intended to be served fresh, nor in meats.² U.S. labeling rules require declaration of sulfiting agents when present at 10 parts per million (ppm) or more in the finished food.⁴ In the EU, “sulphur dioxide and sulphites” must be labeled when present above 10 mg/kg or 10 mg/L, expressed as SO₂.⁵

Does Sulphur dioxide have any benefits?

For food quality, yes. It helps:

• Keep colors bright in fruits and juices by slowing browning.
• Protect delicate flavors and aromas by limiting oxidation.
• Stabilize wines by controlling wild microbes and preserving freshness.

These effects reduce waste, extend shelf life, and improve consistency in taste and appearance.¹

Who should avoid Sulphur dioxide?

Some people are sensitive to sulfites. Reactions can include wheezing or shortness of breath, especially in certain individuals with asthma.⁶ If you know you are sensitive, check labels for “sulphur dioxide,” “sulfur dioxide,” “sulfites,” or E-numbers E220–E228, and choose products accordingly.

Myths & facts

• Myth: “Sulfites are only added to cheap wine.” Fact: Many quality wines use controlled amounts because the antioxidant effect is important for stability.
• Myth: “Organic wine has no sulfites.” Fact: Yeast can naturally produce small amounts of sulfites during fermentation, even if none are added.
• Myth: “Sulfites cause hangovers.” Fact: Hangovers have many causes; sulfite sensitivity is different and mainly affects breathing in some people with asthma.⁶
• Myth: “If it’s not on the label, there are no sulfites.” Fact: Labeling thresholds apply. In the U.S., declaration starts at 10 ppm; in the EU, at more than 10 mg/kg or L as SO₂.⁴⁵

Sulphur dioxide in branded foods

On ingredient lists, look for “sulphur dioxide,” “sulfur dioxide,” or E220. In wines and other products, you may also see related sulfites like sodium metabisulphite (E223) or potassium metabisulphite (E224). If you manage a sensitivity, check the label and, where relevant, the “contains sulphites” statement. U.S. products must declare sulfiting agents at 10 ppm or more, and EU rules require declaration above 10 mg/kg or L as SO₂.⁴⁵

References

Footnotes

1. Re‑evaluation of sulphur dioxide (E 220) and sulphites (E 221–228) as food additives — EFSA Journal. https://www.efsa.europa.eu/en/efsajournal/pub/4438 ↩ ↩² ↩³ ↩⁴

2. 21 CFR 182.3862 — Sulfur dioxide. U.S. eCFR. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-182/subpart-D/section-182.3862 ↩ ↩²

3. Sulfur dioxide — PubChem (NIH). https://pubchem.ncbi.nlm.nih.gov/compound/1119 ↩

4. 21 CFR 101.100(a)(4) — Exemptions from labeling; sulfiting agents threshold. U.S. eCFR. https://www.ecfr.gov/current/title-21/chapter-I/subchapter-B/part-101/section-101.100 ↩ ↩² ↩³

5. Regulation (EU) No 1169/2011, Annex II — Sulphur dioxide and sulphites labeling. EUR-Lex. https://eur-lex.europa.eu/eli/reg/2011/1169/oj ↩ ↩² ↩³

6. CPG Sec. 555.400 — Sulfiting Agents: Adverse Reactions. U.S. FDA. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/cpg-sec-555400-sulfiting-agents-adverse-reactions ↩ ↩²