The present invention provides a method for the production of a flavour-enhancing composition, the method comprising the steps of: i) providing a dairy liquid； ii) nanofiltrating the dairy liquid to obtain a nanofiltration permeate； iii) concentrating the nanofiltration permeate by reverse osmosis and/or evaporation to produce a flavour-enhancing composition, the flavour-enhancing composition comprising at least 50 wt% lactose by dry weight and having a K:Na ratio of at least 2:1, wherein nanofiltrating the dairy liquid uses a membrane having a molecular weight cut-off of from 300 Da to 800 Da.
