The theoretical SO2 yield provided by K2S2O5 is 57%.
A correct use of SO2 allows to obtain less oxidized wines, with a better color and aroma, and a lower volatile acidity, due to its effects as:
- Antioxidant: it possesses reducing properties, capturing oxygen and preventing the appearance of oxidative notes.
- Antioxidase: Destroys oxidases, preventing cracks.
- Antimicrobial: It exerts an inhibitory activity on yeasts, lactic acid bacteria and acetic acid bacteria.
There are several ways of naming this compound, all equally valid, these are: Potassium metabisulfite, potassium disulfite, potassium pyrosulfite and potassium pentaoxodisulfate (IV).
On must or wine.
- In harvest 6 – 16 g/hL or 100kg of grapes
The dosage depends on the state of health of the grapes and the acidity of the musts or wines.
The total sulfur dioxide content may not exceed 150 mg/l for red wines and 200 mg/l for white and rosé wines. If the amount of residual sugar (expressed as glucose+fructose) is equal to or greater than 5 g/l, the permitted values are 200 mg/l for red wines and 250 mg/l for white and rosé wines.