I made 5 gallons of Sauvignon Blanc this past year. I will be ready to bottle in the near future. I read on most commercial wine bottles that they contain sulfites. My understanding this is a stabilizer and to protect the wine yeast from refermentation. I am in the process of sending an order in and would like to know what to use and what amt. per gallon?
Sulfites are added to a wine just before bottling, primarily to help eliminate spoilage and keep the wine's color from turning through a process of oxidation. It does this by killing any traces of wild mold or bacteria that may have found its way to the wine and by driving the oxygen out of the wine.
Sulfites are not affective in squashing a refermentation, particularly if you have added an actual wine yeast to the wine as opposed to relying on wild yeast from the grapes to do the job. Domesticated wine yeast is somewhat resilient to sulfites, while wild yeast can be easily destroyed by it.
If you are concerned with the possibility of a refermentation occurring, you will also want to add potassium sorbate in addition to the sulfites, however this should only be necessary if the wine yeast did not completely ferment all the sugars in the wine must, or if sugar has been added back to the wine before bottling as a means of sweetening it.
The easiest way to add sulfites to your wine is to use sodium metabisulfite. We offer it as a granulated powder. You simply dissolve it into the wine right before you bottle. Make sure that the sodium metabisulfite gets evenly disbursed throughout the entire batch. A good way to go about this is to add the sodium metabisulfite to quart or so of the wine first, to dissolve it. Then blend the mixture into the rest of the batch.
The dosage of sodium metabisulfite you need is very small. You use 1/16 of a teaspoon for each gallon of wine. If you don't have a 1/16 teaspoon, then use 1/8 teaspoon for each 2 gallons of wine. This is the same way wineries go about getting sulfites in the wine.
Happy Wine Making,
Customer Service at E. C. Kraus