Consists of a food grade combination of urea and diammonium phosphate in powder form. Used worldwide by wineries and mead-makers as a basic nitrogen source for fermenting yeasts and as an aid in preventing stuck fermentations. It is also the basic source of nitrogen in nearly all proprietary wine yeast nutrients. It can be used alone or as a supplement to other more expensive nutrient combinations. Typically used at the start of fermentation, with a supplemental addition midway through fermentation.
Normal dose is 1-3 grams per gallon, divided into two portions. The first portion added at the start and the remainder added midway through fermentation. Before adding yeast nutrient it should first be put into solution by mixing with a small quantity of water.