DAP stimulates yeast growth and is a useful addition to yeast starters and wines lacking in natural nutrients like white wines. It is THE SPECIFIC nutrient for mead and pyment. Some winemakers add it to every fermentation with excellent results. Use 1/2 to 3/4 grams per gallon. We sell this in several sizes be sure to check our other items to find it for as little as $4 per pound delivered inside the continental USA.