Molecular characterization of edible vegetable oils via free fatty acid and triacylglycerol fingerprints by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

Abstract

Free fatty acids (FFAs) and triacylglycerols (TAGs) are the main components of edible vegetable oils. In this work, electrospray ionisation (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) was employed to characterise the molecular composition of FFAs and TAGs in various vegetable oils, including soybean, rapeseed, corn, sunflower, peanut, linseed and olive oils. Semiquantitative analysis of FFAs and structural analysis of TAGs by MS/MS were further conducted to reveal the differences in the molecular compositions of the various vegetable oils. It was found that each vegetable oil has characteristic fingerprints of FFAs and TAGs. MS/MS measurements showed that the high-abundance TAGs in each vegetable oil were mainly composed of their abundant FFAs and glycerol. FFA and TAG fingerprints of genetically modified (GM) and nongenetically modified (non-GM) vegetable oils were similar, exhibiting only subtle differences, as confirmed by principal component analysis (PCA).