Uses and Significance of Sulphur Dioxide in Winemaking

Winemaking is a complex, chemical process that involves numerous stages before you can reap the ideal results. One misstep along the way can spoil your wine. Throughout the years, winemakers have experimented with various ingredients and additives to ensure that their wine turns out according to their expectations and desires. An additive that has been useful in their efforts is sulphur dioxide or SO2. While SO2 is produced in small quantities during alcoholic fermentation by the wine yeast, it also is helpful to add it in various stages to reap its full benefits.

The Various Uses and Functions of SO2

  • Sincesulphur dioxide contains antimicrobial and antioxidant qualities, it is an effective preservative for any type of wine. Wine containing sufficient quantities of SO2 has a lower risk of spoilage. It is important to note that there are both bound and free versions of sulphur dioxide in wine. The free version is known to be higher in the above beneficial qualities. High-acidic wine will contain less of the free version of SO2. When adding sulphur dioxide to your batch of wine, please remember that only about 40-percent of it will wind up as the free form.
  • If you intend on storing your wine for a moderate to long amount of time, it will need to contain a higher concentration of SO2 than a table-ready wine does to ensure that its integrity is protected throughout the storage time.
  • You should always ensure that the clarity of your wine is as high quality as possible to receive the full benefits from free SO2. This is because free SO2 can bind easily when the clarity is not as it needs to be, which turns the wine hazy in many cases. As a result, if your wine is hazy, you will need to add more SO2 than you would normally.
  • Insufficient sulphur dioxide in wine will diminish the quality of the wine as well as its shelf life. You may suffer financial losses as a result. This is another reason to ensure that your wine contains proper quantities of SO2.
  • An additional benefit of adding SO2 to wine is that it will bind with any acetaldehyde that is in the wine after oxidation occurs. The reason that this is important is that the acetaldehyde can give the wine an unpleasant odour. SO2 and acetaldehyde binding together removes this unwanted odour.

For further facts about the uses and significance of sulphur dioxide in winemaking, turn to Grapeworks Consumables. We provide a full line of winemaking machinery and equipment along with various additives, including ones to increase the SO2 level in your wine.