It is used for the determination of free SO2 in wine, must, juice and fruit wine.
Take 10 ml of the sample and add the SO2 reagent (shake dropwise before use).
When adding the reagent, gently shake the tube several times to allow the liquid to mix.
When the color is skipped in blue (30 sec.), Read off the amount of added SO2 reagent.
1 ml = 10 mg / l free sulfur