Youngs fermentation stopper 30g potassium sorbate wine stabilizer is used for stabilising and preventing fermentation after bottling to use add 1 gram 12 tsp per gallon of win the potassium sorbate produces sorbic acid when added to winer r it serves two purposesr r when active fermentation has ceased and the wine is racked for the final time after clearing potassium sorbate will render any surviving yeast incapable of multiplying yeast living at that moment can continue fermenting an