White Labs Yeast Nutrient
White Labs Yeast Nutrient (WLN1000) is sold in a 1 oz. package and is used to increase the health of yeast. It will improve fermentation and re-pitching performance. It is an effective boost for first and/or late generation yeast slurry. If the grist is not 100% malt then a yeast nutrient can help make up for the lack of nutrients.
White Labs Yeast Nutrient contains diammonium phosphate, essential vitamins and co-factors, nitrogen (amino acids, proteins, and peptides) and minerals.
For homebrew use, use 1/2 tsp. for every 5 gallons. It should be added during the last 10 minutes of the boil.