Apparent and quantitative loss of fatty acids and triacylglycerols at frying temperatures
Keywords:Fatty acids, Frying, Polar compounds, Polar FAME, Triacylglycerols
Olive and sunflower oils were heated at 180 °C for 5, 10 and 15 hours with the aim of defining the changes in the contents of fatty acid methyl esters (FAME) and triacylglycerols (TAG) under frying conditions. Differences between apparent and real loss of FAME or TAG are defined for an adequate interpretation of the changes taking place at high temperature. Such differences depend on the expression of the results and frequently result in erroneous conclusions. Results showed that from the normalized composition it could be deduced that only the most unsaturated FAME (C18:2) or TAG containing it was significantly altered. However, quantitative data indicated that all the unsaturated FAME were degraded in samples of olive oil and sunflower oil whose levels of alteration ranged from 14.6 to 35.4% polar compounds. With regard to TAG, their loss depended on both the number of double bonds and the concentration of the linoleyl group, which is the most unsaturated fatty acyl group in both oils.
Barrera-Arellano D, Márquez-Ruiz G, Dobarganes MC. 1997. A simple procedure to evaluate the performance of fats and oils at frying temperatures. Grasas Aceites 48, 231-235. http://dx.doi.org/10.3989/gya.1997.v48.i4.794
Carelli AA, Cert A. 1993. Comparative study of the determination of triacylglycerol in vegetable oils using chromatographic techniques. J. Chromatogr. A 630, 213-222. http://dx.doi.org/10.1016/0021-9673(93)80458-K
Cecchi G, S Biasini, Castano J. 1985. Méthanolyse Rapide des Huiles en Solvant. Rev. Franc. Corps Gras 32, 163-164.
Dobarganes MC, Pérez-Camino MC. 1988. Fatty acid composition: a useful tool for the determination of alteration level in heated fats. Rev. Franç. Corps Gras 35, 67-70.
Dobarganes MC, Márquez-Ruíz G. 1998. Regulation of used frying fats and validity of quick tests for discarding the fats. Grasas Aceites 49, 331-335. http://dx.doi.org/10.3989/gya.1998.v49.i3-4.735
Dobarganes MC, Márquez-Ruíz G. 2007. Formation and analysis of oxidized monomeric, dimeric and higher oligomeric triglycerides. In Deep Frying: Chemistry Nutrition and Practical Applications. 2nd edition. Ed. by M.D. Erickson. American Oil Chemists’ Society, (Champaign, Illinois), pp 87-110.
Fernández-Moya V, Martínez-Force E; Garcés R. 2000. Identification of triacylglycerol species from highsaturated sunflower (Helianthus annuus) mutants. J. Agric. Food Chem. 48, 764-769. http://dx.doi.org/10.1021/jf9903861
IUPAC (1992a). Preparation of the fatty acid methyl esters 2.301. In Standard Methods for the Analysis of Oils, Fats and Derivatives, 7th ed.; International Union of Pure and Applied Chemistry, Blackwell Scientific: Oxford, UK, 1992.
IUPAC (1992b). Gas-liquid chromatography of fatty acid methyl esters 2.302. In Standard Methods for the Analysis of Oils, Fats and Derivatives, 7th ed.; International Union of Pure and Applied Chemistry, Blackwell Scientific: Oxford, UK, 1992.
IUPAC (1992c). Determination of polar compounds in frying fats 2.507. In Standard Methods for the Analysis of Oils, Fats and Derivatives, 7th ed.; International Union of Pure and Applied Chemistry, Blackwell Scientific: Oxford, UK, 1992.
How to Cite
Copyright (c) 2012 Consejo Superior de Investigaciones Científicas (CSIC)
This work is licensed under a Creative Commons Attribution 4.0 International License.© CSIC. Manuscripts published in both the printed and online versions of this Journal are the property of Consejo Superior de Investigaciones Científicas, and quoting this source is a requirement for any partial or full reproduction.
All contents of this electronic edition, except where otherwise noted, are distributed under a “Creative Commons Attribution 4.0 International” (CC BY 4.0) License. You may read here the basic information and the legal text of the license. The indication of the CC BY 4.0 License must be expressly stated in this way when necessary.
Self-archiving in repositories, personal webpages or similar, of any version other than the published by the Editor, is not allowed.