Relationship between H2S-producing strains of wine yeast and different fermentation conditions

Hydrogen sulphide formation is a problem in winemaking. One of the factors affecting formation of this unwanted metabolite is the yeast strain respons ible for the process. In this experiment wines were made on a laboratory sc ale with different strains of H2S-producing Saccharomyces cerevisiae. The r elationship between H2S production and various fermentation conditions was examined (SO2, methionine, (NH4)(2)SO4, (NH4)(3)PO4, steel, and steel-lees) . The results show that in fermentations in the presence of stainless steel and lees, H2S formation is high but declines when (NH4)(3)PO4 is added to the must.