Originally Posted by Yooper

Campden kills bacteria and molds, and stuns wild yeast into inactivity. It's very common to keep must at room temperature for 24 hours after adding sulfites to the must before adding yeast. Potassium metabisulfite is the active ingredient in Campden tablets. Its action, in water or wine, inhibits harmful bacteria through the release of sulfur dioxide, a powerful antiseptic. Wine yeast is pretty tolerant of sulfites (that's why winemakers use it) but it's still common to add the yeast 24 hours later as to not stun the yeast.

It can also be used (in a higher concentration) as a sanitizer for equipment and fermenters.

I use one campden tablet per gallon of must (roughly 45-50 ppm of sulfur dioxide) with good results.

Originally Posted by Cpt_Kirks

Patience, my Padawon. The yeast can sense your tension.

Originally Posted by Revvy

Maybe you want to educate yourself instead of just having a bunch of pre-conceived notions based on ignorance.

Originally Posted by nukinfuts29

Right, it stuns them, doesn't kill them.

Originally Posted by Joe_in_CT

If the juice is pasteurized why add Campden?

Originally Posted by Yooper

But it does kill bacteria, and mold. So it's always used for fruits when making up a must. And it stuns wild yeast as to make them unable to ferment. Campden is completely effective, in the correct amount.

Wine yeast is special in that it is amazingly tolerant of sulfites- that's why winemakers use campden in the first place, to sanitize the must, and then use their own yeast strain to ferment.

Originally Posted by Cpt_Kirks

Patience, my Padawon. The yeast can sense your tension.

Originally Posted by Revvy

Maybe you want to educate yourself instead of just having a bunch of pre-conceived notions based on ignorance.