Sodium metabisulfite is an inorganic salt substance. It is also known as disodium or sodium pyrosulfite. The general appearance of sodium metabisulfite, which is solid under normal conditions, is a yellowish powdery color or white. Sodium metabisulfite, which can melt at 150 degrees Celsius, has been used for food preservation for many years. Sodium metabisulfite does not cause any harm to the human body when consumed with food. For this reason, it has been allowed to be used as an additive in foods in many countries, especially in the USA.