Location: Functional Foods ResearchTitle: Reliability of proton NMR spectroscopy for the assessment of frying oil oxidation
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/16/2016
Publication Date: 7/19/2016
Citation: Hwang, H.-S., Winkler-Moser, J.K., Wayman, A.E., Liu, S.X. 2016. Reliability of proton NMR spectroscopy for the assessment of frying oil oxidation [abstract]. Institute of Food Technologists.
Technical Abstract: Although there are many analytical methods developed to assess oxidation of edible oil, it is still common to see a lack of consistency in results from different methods. This inconsistency is expected since there are numerous oxidation products and any analytical method measuring only one kind of oxidation product cannot give a satisfactory description of oil oxidation. For this reason, it has been stressed by several scientists that a method that combines the concomitant detection of many different oxidation products is necessary for a more consistent assessment of oil oxidation. Furthermore, under frying conditions, some standard methods detecting minor oxidation products such as hydroperoxides, conjugated dienes, aldehydes, and epoxides were found to be less reliable than methods detecting major oxidation products such as total polar compounds (TPC), polymerized triacylglycerols (PTAG) and fatty acid composition. The 1H NMR spectroscopy method should be as reliable as these three methods since NMR signals directly reflect the change in fatty acid composition. The aim of this study was to evaluate correlations between the 1H NMR spectroscopy method and the conventional methods measuring TPC, PTAG, and fatty acid composition to confirm the reliability of this method. This study specifically focused on the reliability of the NMR method for soybean oil and two other vegetable oils rich in oleic acid under frying conditions. It was found that the NMR method correlates very well with three conventional methods. Comparisons between our new methods and earlier NMR methods reported by Satio and Shahidi research groups in1980’s and 1990’s will be discussed. This presentation will also provide a convenient procedure for the practical analysis of oxidized oil.