A new simple and selective isocratic LC-ESI-MS method has been developed for the analysis of C1-C6
carboxylic acids in vegetable oils and fats. The compounds include aliphatic and branched C1-C6 fatty
acids and selected oxygenated monocarboxylic acids and dicarboxylic acids. The method requires
minimal sample preparation, offers low ppm level quantification limits or better and produces relatively
clean ion background due to the nature of the acid (HCl) used for the pH adjustment. Development of a
gradient method is foreseen as possible future improvement of the method.
Acknowledgements
The author thanks Mr. Sami Orpana and Mrs. Raija Kekki for assistance. Dr. Toni Laurila is thanked for
fruitful comments and discussions.
ionization efficiency of the analytes. The averaged within run precision and between run precision were
generally lower than 8 %. The accuracy was between 85 and 115 % for most of the analytes. The Lower
Limit of Quantification (LLOQ) ranged from 0.006 to 7 mg/kg. It is shown that this method offers good
selectivity in cases where UV detection fails to produce reliable results