Campden Tablets
These little tablets (Potassium Metabisulfite is the active ingredient) work wonders; not only do they "clean" must prior to pitching yeast, but adding crushed campden tablets to water also makes a great sanitizing solution for winemaking equipment. Each campden tablet supplies about 67 mg / liter (PPM) per gallon at pH between 3.2 and 3.5. As it turns out, it's good to have a little free SO2 in your wine (between 40 - 60 PPM), so there's no need to rinse your equipment after sanitizing with this agent.
METHOD: In order to obtain a sanitizing solution of 940 PPM SO2, crush 14 campden tablets and dissolve into 1 gallon of water