Sodium metabisulfite is a food additive, preservative, antioxidant, and leavening agent.
Sodium metabisulfite also has applications as a sanitizer and cleaning agent for brewing and winemaking equipment and water purification systems.
Sodium metabisulfite is effective in water treatment for the removal of monochloramine from drinking water after treatment; steam boiler water treatment; removal of excess chlorine from wastewater.