Direct Chromatographic Determination of Acetic, Propionic and Butyric Acids in Cheese

New developments in chromatographic techniques have provided the research worker with a long-needed tool for the separation of closely related chemical compounds. In recent years a number of different chromatographic techniques have been developed for the separation of fatty acids Some of these methods involve separation on filter paper, whereas others utilize the g~ow of mobile phase past a fixed immobile phase suspended in a column. In all of the methods either distillation or extraction of the acids from the parent material has been necessary prior to the application of chromatography. This has been necessitated in part by the failure of the various methods to effect the separation of the lower fatty acids from organic acids such as formic and lactic. Ramsey and Patterson (10) found that pyruvic acid interfered in their procedure for the separation of acetic, propionic, and butyric acids. Another factor which makes distillation or extraction necessary is the interference of the water insoluble fatty acids, which form insoluble salts and block the separation of the lower fatty acids.