E223 (sodium metabisulfite)

E223 is sodium metabisulfite. In food technology, this additive is primarily considered a preservative: its task is to slow down spoilage, control the growth of undesirable microorganisms, or maintain product stability during storage.

What is this additive

By nature, E223 is a sulfite preservative and antioxidant. For accuracy, it is important not to confuse it with neighboring E-codes: close numbers often denote salts of the same acid or substances of the same group, but this is not always the same.

Preservatives do not make a product “eternal” and do not fix poor raw materials. They only work within a specific technology: at the right acidity, humidity, temperature, dosage, and sanitary quality of production.

Why it is used

The main mechanism of action: protects against microbial spoilage and discoloration. This is why E223 is used not for taste or nutritional value, but for shelf life, safety, and predictable product quality.

In practice, E223 can be found in products such as wine, dried fruits, juices, potato products, marinades, and semi-finished products. Specific permitted categories and levels depend on the legislation of the country and the type of product.

Nutrition and metabolism

In normal technological doses, preservatives are rarely a significant source of calories, proteins, fats, or carbohydrates. For blood glucose and insulin, the product itself is often more important: sugar, starch, flour, syrups, alcohol, salt, fats, and portion size.

However, frequent consumption of products with preservatives may be a marker of an ultra-processed diet. Therefore, the question is not only about one E-number but about the overall structure of the diet: how many whole foods, proteins, fibers, minerals, and normal foods are in the diet.

Safety and restrictions

E223 is one of the common sulfites; in case of sulfite sensitivity, it should be considered along with E220-E228.

Individual tolerance varies. Sensitive individuals may have reactions to specific groups of preservatives, especially sulfites, benzoates, or nitrite-nitrate products; in case of repeated reactions, it is advisable to compare symptoms with the label and discuss it with a specialist.

How to read the label

E223 may be indicated on the label as an E number or as a name: sodium metabisulfite. It is better to evaluate it together with the function of the additive, the product category, the frequency of consumption, the shelf life, and the complete composition, rather than drawing conclusions solely based on the presence of the E-code.

E223 And Sulfite Sensitivity

E223 belongs to the sulfite group, used to protect color and slow spoilage in wine, dried fruit, juices, potato preparations and some sauces. In keto, many of these foods are also limited because of sugar or starch, especially dried fruit and sweet drinks.

In sensitive people, sulfites may trigger nasal congestion, bronchospasm, hives or headache. With asthma and repeated reactions, the full ingredient list matters and restrictions should be discussed with a clinician, not reduced to “sugar-free” choices.