FNI103 is a water-soluble primary grown yeast peptone of the genus Saccharomyces cerevisae. It is rich in manganese, iron and zinc; it contains a high level of protein in the form of readily and easily assimilated amino acids and peptides. It also contains soluble nucleic acids, vitamins and other factors to stimulate growth and metabolites production. FNI 103 is a spray-dried powder.