Sodium bisulfite
Sodium bisulfite, NaHSO₃, is an inorganic salt that acts as a reducing agent and is used as a preservative and oxygen scavenger.
Bisulfite ion: The hydrogen sulfite anion, HSO₃⁻, formed when sulfurous acid loses one proton. This anion is the reactive species present when sodium bisulfite dissolves.
Wine making: The production of wine through fermentation of grape juice and subsequent processing. Winemakers use sulfites, including bisulfite forms, to limit oxidation and microbial growth.
Sodium metabisulfite: A sodium salt, Na₂S₂O₅, that forms bisulfite species when dissolved in water. It is a widely used, more concentrated source of bisulfite in solution.
Sulfite sensitivity: Adverse reactions to sulfites that occur in a small subset of people, especially some with asthma. Sulfite-containing foods and products can trigger reactions in susceptible individuals.
Sulfur dioxide: A colorless gas, SO₂, that dissolves in water to form sulfurous acid and related sulfur species. Dissolved sulfur dioxide and bisulfite interconvert, especially as pH changes.
Food preservation: Methods that slow spoilage and extend the safe or acceptable life of food. Bisulfite compounds preserve foods by inhibiting browning and some microorganisms.
Sodium sulfite: The sodium salt Na₂SO₃, containing the sulfite ion SO₃²⁻. It is a closely related sodium sulfur oxyanion salt with different protonation.
Food additive labeling: Rules requiring specified ingredients or additives to be declared on food packaging. Sulfite use is subject to declaration requirements in many jurisdictions.
Redox reaction: A chemical reaction involving transfer of electrons and changes in oxidation states. Sodium bisulfite reduces other substances as sulfur in bisulfite is oxidized.
Oxygen scavenger: A substance that chemically removes oxygen from a material or enclosed environment. Sodium bisulfite consumes dissolved oxygen in water and oxygen-sensitive processes.