Simulation of the visible spectra for edible virgin oils: potential uses.

The photodegradation technique was used to record the visible spectra for carotenoids and chlorophylls in virgin olive oil. Principal component analysis of the visible spectra for 81 samples of this type of oil with widely variable composition revealed that only two components contribute more than 99.7% of the spectral information. The Varimax factors and the absorbances of the oil pigments are linearly related. The joint use of these spectra and the absorbances at 455 and 670 nm allows the accurate reproduction of the visible spectrum for any virgin olive oil sample. Therefore, one can question whether a commercially available product is actually virgin olive oil if a comparison of its experimental and simulated absorbance values gives R(2) < 0.995 and RMSD > 0.006. The simulated spectra provide CIE L *a*b* chromatic coordinates that describe the color of the samples with little difference from those provided by the spectra for real samples.