To obtain a flavoring material which has a strong flavoring power and is particularly used for coffee or tea in the form of a long-life small container by adding a stabilizing salt, sugar and the flavoring material to a milk base before or after thickening this milk base by evaporation.

A milk fat and skim milk are mixed and is completely homogenized and, thereafter, the mixture is standardized by a method for adding the sterilized skim milk at a ratio at which the weight ratio of the fat to the nonfat solid preferably attains 0.23 to 0.24 in order to obtain a desirable fat content (more adequately 15wt.%). Next, this mixture is thickened by evaporation and is standardized after cooling. In succession, the mixture is preheated and is subjected to heat sterilizing by UHT. Finally, the mixture is aseptically homogenized and is aseptically packed into a brick, etc., by which the milk base is prepd. Further, the stabilizing salt (more preferably phosphate), the sugar (more preferably sucrose) and the flavoring material are added to the milk base before or after the evaporation.