NuCel 581 PW is a primary yeast peptone obtained by the autolysis of a selected strain of yeast, especially grown on a molasses-based media. Suitable for a broad range of mesophilic and thermophilic lactic bacteria, NuCel 581 PW associated with yeast extract promotes microorganisms growth and can be used during the strain conservation as viability protective agent. NuCel 581 PW is a high quality source of readily available soluble, amino acids, medium-sized peptides, vitamins and essential elements.