Front Face Fluorescence Spectroscopy Combined with PLS‐DA Allows to Monitor Chemical Changes of Edible Vegetable Oils during Storage at 60 °C
Résumé
In this work, front-face fluorescence spectroscopy coupled with chemometric tools are used for the monitoring of rapeseed, sunflower, extra virgin olive, and linseed oil. The oil samples are heated at 60 degrees C for up to 15 days. The fluorescence excitation spectra are scanned in the range of 270-420 nm and 250-310 nm after emission wavelength set at 450 and 330 nm, respectively. The primary and secondary lipid oxidation products are also determined on the same oil samples. By applying partial least square discriminant analysis (PLS-DA) to each spectral collection obtained after emission set at 450 and 330 nm, clear discrimination of edible oil samples according to their botanical types, and sometimes aging, is obtained.
Practical Applications: This study shows that oxidation of rapeseed, sunflower, extra virgin olive, and linseed oil monitored different trends due to their difference in composition. The presented results demonstrated the capability of the front-face fluorescence spectroscopy to differentiate four vegetable oils contained in capped and uncapped flasks indicating the evolution of primary and secondary indicators of oxidation during the storage period. The technology can be exploited at the industrial level for monitoring in a non-destructive manner the level of oxidation of edible oil.