Geographic origins and compositions of virgin olive oils determinated by chemometric analysis of NIR spectra

NIR prediction of fruit moisture, free acidity and oil content in intact olives

“…The applications of NIRS to olive oil and other oils has been the subject of a wider investigation. Galtier et al (2007) successfully identified the geographical origin and composition of virgin olive oils through a chemometric analysis of the NIRS spectrum. Costa et al (2008) determined acidity, refractive index and viscosity in corn, soybean, canola and sunflower oils using this technology.…”

Quality Evaluation of Olives, Olive Pomace and Olive Oil by Infrared Spectroscopy

“…show NIR spectra of olive oil, hammer milled olive and olive pomace. The following main spectroscopic regions can be observed: the region between 9000 -8000 cm -1 , can be ascribed to the second overtone of the C-H stretching vibration of modes of methyl, methylene and ethylene groups of fatty acids and triacylglycerols; the region between 7500 and 6150 cm -1 can be attributed to the first overtone of the O-H stretching vibrations; whereas the absorptions located around 6000 -5700 cm -1 correspond to the first overtone of the C-H stretching vibration modes of methyl, methylene and ethylene groups; in next region bands between 5350 and 4550 cm -1 result from combinations of fundamentals of the C-H stretching vibration and of bands of water molecules (specially in olives and olive pomace); finally, the 4370 -4260 cm -1 region can be ascribed to the C-H stretching combination of methyl and methylene groups (Galtier et al 2007;Muick et al 2004). …”

“…Near infrared spectroscopy has been valuable for the assessment of physicochemical parameters of vegetable oils (Sato 1994;Hourant et al 2000;Takamura et al 1995;Franco et al 2006). Infrared spectroscopy (NIR and MID), has also been applied successfully for olive oil evaluation and geographical origin determination using chemometric approaches (Tapp et al 2003;Iñón et al 2003;Galtier et al 2007). In addition, NIR technique was employed to detect fraudulent addition of other vegetable oils and olive pomace oil, to virgin olive oil (Wesley et al 1995;Yang & Irudayaraj 2001;Doweny et al 2002;Vlachos et al 2006); and for olive oil authentication (Bertran et al 2000;Downey et al 2003;Woodcock et al 2008).…”

“…It will be necessary to add more samples with wider ranges of parameters in order to enhance the robustness of the models. Galtier et al (2007) have managed to quantify 14 fatty acids, squalene and triacilglycerols.…”

Optical Absorption Spectroscopy for Quality Assessment of Extra Virgin Olive Oil

“…The NIR band was used to classify French oils from several regions holding quality labels as registered designation of origin; squalene and fatty acids were also predicted (Galtier et al, 2007). The NIR was also used to classify Spanish oils (Bertran et al, 2000), to predict acidity and peroxide index (Armenta et al, 2007), and to detect and quantify the adulteration with sunflower and corn oil (Özdemir et al, 2007) and other vegetable oils (Christy et al, 2004;Öztürk et al, 2010).…”