Diammonium Phosphate (DAP). A source of nitrogen for yeast. Use 1/2-3/4 grams per gallon (1/2 tsp per 5 gallons) of must to aid yeast and help reduce later problems with hydrogen sulfide. A rough approximate of weight is 1 tsp = 3.1 grams. We highly recommend using a scale to weigh the product for an accurate dose. We do not recommend relying on these rough conversions for accurate dosage rates.