E224 As Preservative

E224 is the European designation for potassium metabisulfite, a white crystalline powder. It is a salt of sulfurous acid, produced industrially by reacting potassium carbonate with sulfur dioxide. It is often used as a source of sulfur dioxide in food applications.

Potassium metabisulfite functions as a preservative and antioxidant. It helps prevent spoilage by inhibiting the growth of bacteria and fungi, and it can also prevent browning in fruits and vegetables. It is commonly found in dried fruits, wines, and some processed potato products.

In the US, potassium metabisulfite is permitted as a preservative and antioxidant under FDA regulations. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has evaluated potassium metabisulfite and established an acceptable daily intake. Some individuals, particularly those with asthma, may be sensitive to sulfites and experience allergic-type reactions. The FDA requires foods containing more than 10 parts per million of sulfites to declare them on the label.