OP B7. EFFECT OF THERMAL STRESSING ON SATURATED VEGETABLE OILS –
PRODUCT ANALYSIS BY MALDI-TOF MASS SPECTROMETRY
J. Schiller,1 M. Petković2,R. Süß1, and K. Arnold1
1 Institute of Medical Physics and Biophysics, Faculty of Medicine, University of Leipzig, Germany
2 Department of Physical Chemistry, Institute of Nuclear Sciences, “ Vinča”, PO Box 522, 11000 Belgrade,
E-mail: marijanapetkovic@vin.bg.ac.yu
It is well-known that triacylglycerols of vegetable oils undergo oxidative modifications at elevated temperatures. This was shown primarily for oils with unsaturated fatty acid residues that are most sensitive towards oxidation. Saturated oils, however, were by far less investigated. In this paper completely saturated oils (coconut oil) as well as isolated, saturated triacylglycerols, (TAGs) were exposed to a defined thermal stress and the resulting products investigated in dependence on temperature and heating time.
Matrix-assisted laser desorption and ionization (MALDI-TOF) mass spectrometry (MS) was used for the characterisation of the native and well as the thermally-stressed oil samples. This method was used because it provides fast and reliable information on oil composition and can be performed faster than other established methods.
It was found that the degradation mechanisms of triacylglycerols with saturated fatty acids are completely different in comparison to unsaturated ones. Whereas the fatty acids of unsaturated oils are primarily depleted under cleavage of the double bonds, saturated oils show the conversion of one methylene group into a carbonyl group.
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