[2] It decomposes at 190 °C, yielding potassium sulfite and sulfur dioxide: It is used as a food additive, also known as E224.

[4] Potassium metabisulfite is a common wine or must additive, in which it forms sulfur dioxide (SO2).

A high dose would be 3 grams of potassium metabisulfite per six-gallon bucket of must or around 132 milligrams per liter (yielding roughly 75 ppm of SO2) prior to fermentation; then 6 grams per six-gallon bucket (150 ppm of SO2) at bottling.

[5] Winemaking equipment is sanitized by spraying with a 1% SO2 (2 tsp potassium metabisulfite per L) solution.

Potassium metabisulfite is sometimes used in the brewing industry to inhibit the growth of wild bacteria and fungi.