The invention provides a method for producing a flavoured milk product, the method comprising the steps of: (a) providing milk source； (b) fermenting the milk source using at least one microorganism, to produce a fermented milk source having an acidic pH； and (c) increasing the pH of the fermented milk source using ammonia, wherein the ammonia reacts to produce 2,3,5,6-tetramethyl pyrazine.
