What is Free SO2?
Sulphur Dioxide or SO2 is a compound used in winemaking, to protect from the negative effects of oxygen exposure as well as spoilage microorganisms. However, due to the unique nature of each individual wine, those running the fermentation and quality process cannot simply add a generic or standard amount of SO2. The levels added are affected by the amount of SO2 that becomes bound to compounds in the wine, and this in turn is determined by the pH levels. The Sulfur dioxide ions that are not chemically bound to other chemicals in solution and thus are free to react with substances are known as Free SO2.
No of Tests
Why test for Free SO2?
Measuring sulphites in wine is important for a number of reasons. If levels exceed 10mg/L producers must include a statement on the label, as sulphites can aggravate allergies and intolerances. Wine exporters must also bear in mind variations in national regulatory thresholds.