An Improved Liquid Chromatographic Method for the Quantitative Determination of Free Fatty Acids in Milk Products

Abstract

An existing HPLC method for the quantitative determination of the major FFA in milk fat was improved. Complete resolution of the p-bromophenacyl (PBP) ester derivatives of saturated and unsaturated FFA of acyl-chain length (24 to C18 was accomplished by gradient elufion (60 to 100% acetonitrile in water) when the temperature of the reverse-phase column was maintained at 10*C. This allowed the determination of all the major FFA in milk fat within a single chromatographic analysis. The improved method should save time in analysis of FFA in milk fat and also can be used to quantify the low concentrations (78 to 270 pM + 17%) of the major FFA (myristic, palmitic, stearic, and oleic acids) in fresh pasteurized milk and follow the time course of milk fat hydrolysis where low amounts of FFA are liberated.