Sodium Metabisulfite is a wine sanitizer and preservative created to prevent microbial and oxidation spoilage in musts. Available in powdered form, thoroughly dissolve in warm water before gently stirring into must or wine. Sodium Metabisulfite contains sodium ions and due to dietary needs, some winemakers avoid the Sodium version and substitute Potassium Metabisulfite instead.
To learn the proper dosing methods for using Sodium or Potassium Metabisulfite throughout the wine production process, Brew and Grow recommends reading Daniel Pambianchi, Techniques in Home Wine Making. Comprehensive and accessible, the author offers tips and tricks for producing fine finished wines from the beginning to the conclusion of the process.
Certain municipalities disinfect water supplies by add chloramines or chlorine. Both water decontaminants can produce off flavors in wine, mead or cider. The disinfectants prove especially problematic in beer brewing by interacting with malt phenols in the brewing process and creating unfavorable Phenolics in the finished beer.
Sodium and/or Potassium Metabisulfite can be employed to reduce both disinfecting compounds to insignificant levels. 1 Campden tablet for 20 – gallons of water will perform the reduction in 5 minutes while 1 tablet in 5 – gallons will not produce off flavors and will be as effective.
To reduce the effects of Chlorine or Chloramine with powdered Potassium or Sodium Metabisulfite, weigh out ½ gram of each to neutralize the disinfecting compounds in 5 – gallons of water.
For killing wild yeast in cider or wine musts, add 1/4 tsp per 6 – gallons. To create a sulfite sanitizer, add 2 oz per 1 – gallon of water.