Determination of Fatty Acid Profiles and TAGs in Vegetable Oils by MALDI-TOF/MS Fingerprinting
Vegetable oils are complex mixtures containing a wide range of major compounds. Triacylglycerols (TAGs; consisting of a glycerol moiety with each hydroxyl group esterified to a fatty acid) are the major components (95–98%) of vegetable oils. TAGs are an important source of energy and nutrition for humans, so their compositional analysis merits extensive interest. Analysis of TAGs has increased in recent years and the advancement has been driven by the development of analytical technologies. This chapter discusses techniques for determination of TAG and fatty acid profiles (FAPs) of vegetable oils using matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF/MS) and gas chromatography–mass spectrometry (GC/MS). Considering the importance of TAG in its native form, rather than FAPs, special emphasis has been given to the TAG fingerprinting analyses of intact oils. MALDI-TOF/MS also enabled calculation of the main fatty acids and their compositions in a simple manner from the TAG profiles; the results are found to be very similar to the prevailing methods of derivatization using GC/MS. This study depicts the potential of MALDI-TOF/MS as an easy, fast, and reliable technique to characterize the TAG and FAPs in vegetable oils.
Key wordsVegetable oils Fatty acid profiles Triacylglycerols MALDI-TOF/MS GC/MS
The authors would like to thank the Ramat Negev Desert Agro Station for providing the olive oil samples. Our appreciation to Dr. Mark Karpasas, Dr. Leonid Kagon, Ms Maya Kaufman, and Ms Shosh Avni for technical help, and Ms Edna Oxman in editing this manuscript.
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