Multivariate analysis of HT/GC-(IT)MS chromatographic profiles of triacylglycerol for classification of olive oil varieties.
The ability of multivariate analysis methods such as hierarchical cluster analysis, principal component analysis and partial least squares-discriminant analysis (PLS-DA) to achieve olive oil classification based on the olive fruit varieties from their triacylglycerols profile, have been investigated. The variations in the raw chromatographic data sets of 56 olive oil samples were studied by high-temperature gas chromatography with (ion trap) mass spectrometry detection. The olive oil samples were of four different categories ("extra-virgin olive oil", "virgin olive oil", "olive oil" and "olive-pomace" oil), and for the "extra-virgin" category, six different well-identified olive oil varieties ("hojiblanca", "manzanilla", "picual", "cornicabra", "arbequina" and "frantoio") and some blends of unidentified varieties. Moreover, by pre-processing methods of chemometric (to linearise the response of the variables) such as peak-shifting, baseline (weighted least squares) and mean centering, it was possible to improve the model and grouping between different varieties of olive oils. By using the first three principal components, it was possible to account for 79.50% of the information on the original data. The fitted PLS-DA model succeeded in classifying the samples. Correct classification rates were assessed by cross-validation.
Department of Analytical Chemistry, University of Granada, Av. Fuentenueva s.n., 18071 Granada, Spain.
Cristina
C
Ruiz-Samblás
Luis
L
Cuadros-Rodríguez
Antonio
A
González-Casado
Francisco de Paula
Fde P
Rodríguez García
Paulina
P
de la Mata-Espinosa
Juan Manuel
JM
Bosque-Sendra
D016002:Discriminant Analysis; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods* / Q000706:statistics & numerical data; D015999:Multivariate Analysis; D000069463:Olive Oil; D010938:Plant Oils / Q000032:analysis* / Q000145:classification*; D025341:Principal Component Analysis; D014280:Triglycerides / Q000032:analysis*
D000069463:Olive Oil; D010938:Plant Oils; D014280:Triglycerides