Determination of fatty acid contents in infant formula by isotope dilution-gas chromatography/mass spectrometry

Abstract An isotope dilution-gas chromatography/mass spectrometry (ID-GC/MS) method was developed as a candidate reference method for the accurate determination of the amount of fatty acids in infant formula. 13 C- or 2 H-labeled fatty acids were used as internal standards to correct for recovery and instrument sensitivity during sample preparation and MS measurements, respectively. The developed ID-GC/MS method was validated based on the repeatability and reproducibility of selected fatty acid analyses. For fatty acid measurements in a homogenized infant formula, the repeatability and the reproducibility were