E222 – Sodium hydrogen sulphite

Description

White crystalline powder with a pungent odour

Risks

Notes

Sodium hydrogen sulfite, also known as sodium bisulfite, is a synthetic preservative that typically appears as a white crystalline powder with a distinctive pungent, sulfur-like odor. It's manufactured by treating sodium carbonate with sulfur dioxide gas under controlled conditions, creating a compound that's closely related to sodium sulfite but with slightly different chemical properties. The production process is similar to other sulfite preservatives, resulting in a standardized industrial chemical used specifically for food preservation. This preservative functions primarily as an antioxidant and antimicrobial agent, preventing foods from spoiling, discoloring, or developing off-flavors during storage. You'll commonly find sodium hydrogen sulfite in dried fruits, fruit juices, wine and beer production, and various processed foods where preventing browning and bacterial growth is crucial. It's particularly effective in acidic foods and beverages, where it helps maintain both the appearance and safety of products throughout their shelf life. As a synthetic additive, sodium hydrogen sulfite is suitable for vegans and vegetarians, but it carries the same important health warning as other sulfites: it can cause severe allergic reactions in sulfite-sensitive individuals, especially those with asthma. Foods containing this preservative above certain thresholds must be clearly labeled in most countries. While safe for the majority of consumers, people with sulfite sensitivity should carefully avoid products containing this additive, as reactions can range from mild respiratory symptoms to serious allergic responses.