Potassium Metabisulfite (sanitizer):
Theoretically it is 57% SO2. 1/4 teaspoon per 5 gallons yields about 40 to 45 ppm. One gram per gallon equals roughly 150 ppm SO2. Replace at least every 18 months and keep in a dry place. Sodium bisulfite acts in the same way, but may not be used in wine produced by US commercial wineries.
taken from
http://winemaking.jackkeller.net/wineblog6.asp
Sulfite Solutions (from jack keller website)
I was asked about the strength used for sanitizing winemaking equipment, bottles and countertops and how to measure potassium metabisulfite for a 10% sulfite solution.
I use a solution made by adding
one level teaspoon of potassium metabisulfite to one gallon of water. A 2-minute exposure to this will kill any known bacteria or mold likely to be in a kitchen or winery. This solution is undoubtedlyly stronger than it needs to be, but I just want to be sure the job is done when I use it. Its use hurts nothing. After use, I then pour it back into a gallon jug, cap it, and reuse it. It lasts much longer than I keep it, which is around 3-4 months.
A 10% sulfite solution is easy to make if you have precise scales. A liter of water weighs 1,000 grams, so add 100 grams (3.5 ounces) of potassium metabisulfite to one liter of water. For a 5% sulfite solution, use 50 grams (1.75 ounces) of potassium metabisulfite to one liter of water.
taken from
[COLOR="Magenta"][COLOR="Red"]http://winemaking.jackkeller.net/wineblog6.asp[/COLOR][/COLOR]
I am really confused when trying to read jack keller
the equation earlier was citric acid added to drop down the ph to approx 3.5 (equivent to wine) then you would use the calcuation to see how much sulfite is needed
I would still like to find out how many PPM does it take to become an efficient santizer?
thanks steve