E226 - Calcium sulphite

At a glance

• What it is: An inorganic calcium salt of the sulphite ion, used as a preservative and anti-browning agent.
• What it does: Controls microbes and slows oxidation, helping foods keep their color and taste.
• Where it’s used: Common in wine, dried fruit, some pickled foods, and certain potato and seafood products.
• Diets: Mineral-based; suitable for vegetarian and vegan diets.
• Sensitivities: A small number of people react to sulfites; those with asthma are more likely to be sensitive.
• Oversight: Regulated as part of the sulfite group (E220–E228) in the EU; in the U.S., sulfites must be declared on labels when present at or above 10 ppm.

Why is Calcium sulphite added to food?

Food makers use calcium sulphite to protect flavor, color, and freshness. In moist or acidic foods, it can release sulfur dioxide, which inhibits spoilage microbes and slows enzymatic browning. This is why sulfites are grouped as preservatives and antioxidant agents in food law.¹

What foods contain Calcium sulphite?

You’re most likely to see sulfites, including calcium sulphite, in:

• Fermented drinks such as wine and cider
• Dried fruits like apricots and raisins
• Some prepared potato products (for example, peeled or cut potatoes)
• Pickled vegetables and condiments
• Crustaceans (such as shrimp) and some seafood products
• Fruit juices and concentrates

These uses reflect how sulfites help keep color and prevent spoilage across many categories.¹ On U.S. labels, any added sulfite at 10 parts per million (ppm) or more must be declared, so look for “sulfites,” “sulphites,” or the specific name (for example, “calcium sulfite”).² In the EU, other members of the same group you may see include sulphur dioxide, sodium sulphite, sodium bisulphite, sodium metabisulphite, and potassium metabisulphite.

What can replace Calcium sulphite?

Swapping depends on the job you need done:

• To limit browning in cut fruit and potatoes: ascorbic acid or citric acid
• To inhibit yeasts and molds in some foods: potassium sorbate
• To control microbes in acidic beverages: sodium benzoate
• Non-additive options: Good hygiene, fast chilling, modified-atmosphere packaging, pasteurization, or vacuum packing

Effectiveness and taste impact vary, so producers often trial combinations to match sulfite performance.

How is Calcium sulphite made?

Calcium sulphite is the calcium salt of the sulphite ion. Food-grade material must meet identity and purity criteria set in EU additive specifications (for example, limits on contaminants and definition of content expressed as sulfur dioxide equivalents).³

Is Calcium sulphite safe to eat?

Regulators assess sulfites as a group. The World Health Organization (WHO) and Food and Agriculture Organization (FAO) Joint Expert Committee on Food Additives (JECFA) established a group acceptable daily intake (ADI) of 0–0.7 mg per kg of body weight per day, expressed as sulfur dioxide equivalents.⁴ The European Food Safety Authority (EFSA) kept this group ADI in its 2016 re-evaluation and noted that while most consumers stay within it, high intakes in some groups could exceed the ADI.¹ A small proportion of people, particularly some with asthma, can experience sensitivity reactions (for example, wheezing, hives, or flushing) to sulfites.⁵

In the United States, added sulfites at or above 10 ppm must be declared on the label, which helps sensitive consumers avoid them.²

ADI = acceptable daily intake, the amount considered safe to consume every day over a lifetime.

Does Calcium sulphite have any benefits?

It does not add nutrition, but it has clear technological benefits:

• Helps keep flavors and colors stable
• Reduces waste by slowing spoilage and browning
• Supports consistent quality in products like wine, dried fruit, and processed potatoes

Who should avoid Calcium sulphite?

• People with diagnosed sulfite sensitivity or those who have reacted to sulfite-containing foods should avoid it.⁵
• Some people with asthma are more likely to be sensitive; consult a healthcare professional if you suspect reactions.⁵

Tips:

• In the U.S., check labels for “sulfites/sulphites” or the specific additive name when present at ≥10 ppm.²
• In the EU, look for the additive name or its E-number (E226).

Myths & facts

• Myth: “Sulfites are banned.” Fact: They are permitted in the EU under food additive law when used as directed.⁶ In the U.S., they are allowed but must be declared on the label at or above 10 ppm.²
• Myth: “Sulfite reactions are classic food allergies.” Fact: Most reactions are sensitivities or intolerances, not IgE‑mediated allergies.⁵
• Myth: “Calcium sulphite is the same as calcium sulfate.” Fact: They are different compounds with different properties and uses.

Calcium sulphite in branded foods

On ingredient lists, this additive may appear as “calcium sulphite,” “calcium sulfite,” or “E226.” Some brands also group it under “sulfites.” Products that advertise “no sulfites added” usually avoid the whole group, not just E226. If you are sensitive, check the label every time, since suppliers and recipes can change.

References

Footnotes

1. Re‑evaluation of sulfur dioxide (E 220) and sulfites (E 221–228) as food additives — EFSA Journal (2016). https://efsa.onlinelibrary.wiley.com/doi/10.2903/j.efsa.2016.4438 ↩ ↩² ↩³

2. Food labeling; exemptions — 21 CFR 101.100 (U.S. FDA). https://www.ecfr.gov/current/title-21/section-101.100 ↩ ↩² ↩³ ↩⁴

3. Specifications for food additives listed in Annexes II and III — Commission Regulation (EU) No 231/2012. https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32012R0231 ↩

4. Sulfur dioxide and sulfites (addendum); evaluation of certain food additives — JECFA (WHO/FAO). https://inchem.org/documents/jecfa/jecmono/v50je06.htm ↩

5. Sulfite sensitivity — MedlinePlus, U.S. National Library of Medicine (NIH). https://medlineplus.gov/ency/article/002550.htm ↩ ↩² ↩³ ↩⁴

6. Food additives framework — Regulation (EC) No 1333/2008 (European Parliament and Council). https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A32008R1333 ↩