North Mountain Supply Food Grade Yeast Nutrient - 3.5 Ounce Jar. Packaged in a plastic jar with a tamper evident air tight seal to ensure quality and freshness! Yeast nutrient is a mixture of diammonium phosphate and food-grade Urea. Gives nourishment to your yeast so that it stays healthy throughout the Fermentation process. Add one teaspoon per gallon recommended for wine, beer, mead, and cider.