Used to increase the health of the yeast. Improves fermentation and re-pitching performance. It contains diammonium phosphate, essential vitamins and co-factors, nitrogen (amino acids, proteins, and peptides) and minerals. Effective boost for first and/or late generation yeast slurry. If grist is not 100% malt, then yeast nutrient can help make up for lack of nutrients. For commercial use, each vial contains 1.0 oz, enough for 5bbls. For homebrew use, each 1/2 tsp. from the vial is good for 5 gallons. This nutrient should be added during the last 10 minutes of the boil.