Molecular Sulphur Dioxide (SO2)
Sulphur Dioxide generally appears in 3 forms, sulphite, bisulphite and molecular. Molecular SO2 is a strong inhibitor of cell growth and the amount of SO2 present in the molecular form is governed by the pH level. In Vinsight, if you have a measurement of pH and Free SO2 then the app will calculate the molecular SO2 using your choice of the formulas below.
The default formula is
10(1.77 – pH) x Free SO2
or if you prefer you can use the formula that the Australian Wine Research Institute use:
Free SO2 / (1 + 10(pH – 1.81))
You can change this setting in the app at Settings > Advanced Settings > Lab Analysis