Sulfites are well-known additives in foods and beverages used to extend shelf life and preserve colors. Such properties have led to the broad usage of sulfites in a range of foodstuffs like fruits, cereals, vegetables, seafood, juices, alcoholic and non-alcoholic (soft) beverages, and in some meat products. The term «sulfites» describes a group of molecules that include sulfur dioxide (SO₂) and chemically related molecules like sodium sulfite (Na₂SO₃), sodium bisulfite (NaHSO3), or sodium metabisulfite (Na₂S₂O₅).

Sulfite intake has been correlated with several adverse reactions, and therefore sulfites are included in the FAO/WHO Codex Alimentarius list. Labelling sulfite content in foods and beverages is necessary when the total concentration exceeds 10 mg/kg. Metrohm ion chromatography allows the reliable measurement of sulfite in different matrices using either conductivity or amperometric detection. The inclusion of automated sample preparation and cleaning steps with Metrohm instrumentation saves additional analyst time and helps increase sample throughput.