Yeast nutrients in a grape juice or must are an important part of any successful and healthy fermentation. The yeast needs supply of carbon, nitrogen, phosphorous also minerals and vitamins as well. These components are naturally present in the grapes, but if they are lacking there is a danger of the production of hydrogen sulphid or problematic fermentation. The simple solution for the lack of nutrients is addition of ammonium compound, such as diammonium phosphate (DAP) or ammonium sulphate and vitamin such as thiamine, which will help increase yeast viability and reduce the risk of lagging or stuck fermentation.