Sulphites are salts of sulphurous acid; together with sulphur dioxide they are used as preservatives and antioxidants (E220 to E228). They prevent browning and the growth of micro-organisms, for instance in wine and dried fruit. As allergen no. 12 they have to be declared above 10 mg/kg or 10 mg/litre.

Above what amount do sulphites have to be declared?

Above a concentration of more than 10 mg/kg or 10 mg/litre in terms of the total SO2, calculated for the product as proposed ready for consumption or as reconstituted (Annex II no. 12). Below that threshold there is no allergen labelling obligation.

What does "sulphured" mean?

It indicates that a food has been treated with sulphur dioxide or sulphites — typical for dried apricots and other dried fruit. It concerns the allergen sulphur dioxide and sulphites, not an additive category statement such as "with preservative".

Which foods contain sulphites?

Commonly wine and sparkling wine, dried fruit (apricots, raisins), dried vegetables and dried potato products, fruit juice concentrates, vinegar and pickled vegetables, some seafood and various convenience foods. They only have to be declared above 10 mg/kg or 10 mg/litre as total SO2.

What are the symptoms of sulphite intolerance?

It is usually an intolerance rather than a classic IgE-mediated allergy. Possible reactions are breathing difficulties up to asthma attacks (especially in people with asthma), headaches, skin flushing or hives, a blocked nose and digestive complaints. This text does not replace medical advice.

Guide · Allergens

Sulphur dioxide and sulphites — allergen no. 12

2 July 2026 · about 7 min read

Sulphur dioxide and sulphites are the odd one out among the 14 allergens: this is the only entry that only has to be declared above a certain concentration — and it often hides behind E numbers. Here is what sulphites are, where they sit and how to label them.

What are sulphites and sulphur dioxide?

Sulphur dioxide (SO₂) and its salts, the sulphites, are sulphur compounds used as preservatives and antioxidants. They inhibit micro-organisms, stop browning (oxidation) and stabilise colour and taste. So they turn up wherever shelf life and colour matter — above all in wine and dried fruit.

In sensitive people sulphites can trigger intolerance reactions (breathing difficulties or headaches, for instance). That is why they appear in Annex II of the FIC Regulation (Regulation (EU) No 1169/2011) as number 12.

When do sulphites have to be declared?

Unlike every other allergen, this entry carries a concentration threshold. Annex II no. 12 reads: “Sulphur dioxide and sulphites at concentrations of more than 10 mg/kg or 10 mg/litre in terms of the total SO₂ which are to be calculated for products as proposed ready for consumption or as reconstituted according to the instructions of the manufacturers”.

Two details in that wording are easy to miss: the figure is the total SO₂, not the amount of any single additive, and it is measured on the product as it is eaten — so a concentrate has to be assessed after reconstitution. Below the threshold there is no allergen labelling obligation.

Hidden behind E numbers: E220–E228

As additives, sulphites often appear only as an E number. Those count as the allergen indication, and — like every allergen — they have to be emphasised:

E number	Substance
E220	Sulphur dioxide
E221	Sodium sulphite
E222	Sodium hydrogen sulphite
E223	Sodium metabisulphite
E224	Potassium metabisulphite
E226	Calcium sulphite
E227	Calcium hydrogen sulphite
E228	Potassium hydrogen sulphite

Where sulphites occur

Food (group)	Why / typical
Wine, sparkling wine, beer	Preservation and protection against oxidation — hence “contains sulphites” on wine bottles.
Dried fruit	Apricots, raisins, figs, prunes — often sulphured, and frequently the highest levels of all.
Dried vegetables & dried potato products	Instant mash, par-fried chips — against browning.
Fruit juice concentrates	Preservation of the concentrate before further processing.
Vinegar & pickles	Pickled vegetables, some mustard and sauce products.
Seafood	Prawns and shrimp, for instance — sometimes treated with sulphites against black spot.

Sulphite intolerance: possible symptoms

Reactions to sulphites are usually an intolerance rather than a classic IgE-mediated allergy. People with asthma are affected above all. Possible complaints:

Airways — coughing, tightness, up to asthma attacks.
Skin — flushing, itching, hives.
Head & circulation — headaches, rarely circulatory reactions.
Digestion — nausea, cramps, diarrhoea.

That is exactly why labelling above the 10 mg threshold matters — sensitive people can then avoid the products that carry a lot of it. This section is general information and does not replace medical advice.

How to label sulphites correctly

On prepacked food, the indication (“sulphur dioxide”, “sulphites” or the E number) has to be emphasised in the list of ingredients under Article 21(1)(b) — usually in bold. For food sold without prepackaging, Article 44(1)(a) makes the allergen particulars mandatory, with the means left to the Member States under Article 44(2) — in Germany § 4 LMIDV.

Worth keeping apart: “sulphured” concerns the allergen sulphur dioxide and sulphites — not an additive statement such as “with preservative”. More on that distinction in allergen labelling in a bakery.

This article is general information and does not replace legal or medical advice. What counts is the wording of the regulation as it applies at the time (Annex II no. 12 of Regulation (EU) No 1169/2011). The English text of the Regulation is quoted from the consolidated version of 1 January 2018 on EUR-Lex.