Allervibe
E224
Potassium metabisulphite
The potassium form of metabisulphite, used mainly as a preservative and antioxidant in wine and cider.
i Additive Details
| Is E224 Potassium metabisulphite safe?
Sulphites are one of the 14 allergens that must be declared under EU Regulation 1169/2011 whenever they are present above 10 mg/kg or 10 mg/litre expressed as SO2. Sulphite sensitivity is well documented in people with asthma, who may react with wheezing, chest tightness or bronchospasm. Most sulphite reactions are intolerance rather than classical IgE-mediated allergy, although rare IgE-mediated cases have been reported. Wine and cider are among the largest dietary sources of sulphites, and any wine above 10 mg/L of SO2 must carry a sulphites declaration even when none was deliberately added, because fermentation itself produces some.
| Uses
Performs the same job as sodium metabisulphite but contributes potassium instead of sodium, which is why it is the standard sulphite in winemaking, cider and fruit wines. Winemakers use it both to protect must and wine from oxidation and to suppress unwanted yeasts and bacteria. It is also used in fruit juices and concentrates, dried fruit and some vegetable products.
| Interactions
It dissolves to give bisulphite ions, which bind acetaldehyde and other carbonyl compounds in wine, so only part of what is added stays free and active as a preservative. It temporarily bleaches anthocyanins, which can lighten the colour of young red wines, and it degrades thiamine (vitamin B1). Ascorbic acid is often used alongside it as an oxygen scavenger.
| Origin
Produced by passing sulphur dioxide into a potassium carbonate or potassium hydroxide solution and crystallising the salt. Small amounts of sulphite also arise naturally during alcoholic fermentation, independently of anything added.
| Daily Intake
A group ADI of 0.7 mg per kg of body weight per day, expressed as SO2, applies jointly to E220 to E228 rather than to each salt individually. EFSA's 2022 follow-up to its re-evaluation of the group concluded that the available data are not sufficient to confirm the ADI and that estimated intake can exceed it in some consumer groups.
Information is sourced from public regulatory bodies (EFSA, FDA, WHO) and is for reference only. Always read the package and consult a healthcare professional for medical advice.
Related additives
- E221 Sodium sulphite A soluble sodium salt of sulphurous acid used as a preservative and antioxidant.
- E222 Sodium bisulphite The sodium salt of hydrogen sulphite, supplied as an aqueous solution and used as a preservative and antioxidant.
- E223 Sodium metabisulphite A white crystalline salt that releases sulphur dioxide in water and is the most widely used sulphite preservative.
- E226 Calcium sulphite A calcium salt of sulphurous acid with low water solubility, used as a preservative and antioxidant.
- E227 Calcium bisulphite A calcium sulphite that exists only in solution, used as a preservative and antioxidant.
- E228 Potassium bisulphite A potassium sulphite supplied as an aqueous solution and used as a preservative and antioxidant.
Spot Potassium metabisulphite with Allervibe
Reading every line of the ingredient list to find a single additive takes time. Allervibe pulls the full additive breakdown from each scan so you can see Potassium metabisulphite at a glance.
- ▮ Scan a barcode to see every additive listed for that product
- ▲ Open any additive for plain-language information
- ↻ Save products to favorites so repeat checks are instant