A fermentation of a milk source to manufacture a fermented milk product with malty chocolate honey butter cream flavour and aroma. Fermentation is achieved by addition of adding a Lactococcus lactis subsp. lactis diacetylactis (CNCM No. I 4404) or a Lactococcus lactis subsp. lactis diacetylactis (CNCM No. I 4405) A further bacteria Lactococcus lactis subsp. lactis biovar is also added to the milk source. The milk source comprises amino acids and citrate prior to fermentation.