| Abstract
| - A combination of 1H NMR and 31P NMR spectroscopy and multivariate statistical analysis was usedto classify 192 samples from 13 types of vegetable oils, namely, hazelnut, sunflower, corn, soybean,sesame, walnut, rapeseed, almond, palm, groundnut, safflower, coconut, and virgin olive oils fromvarious regions of Greece. 1,2-Diglycerides, 1,3-diglycerides, the ratio of 1,2-diglycerides to totaldiglycerides, acidity, iodine value, and fatty acid composition determined upon analysis of therespective 1H NMR and 31P NMR spectra were selected as variables to establish a classification/prediction model by employing discriminant analysis. This model, obtained from the training set of128 samples, resulted in a significant discrimination among the different classes of oils, whereas100% of correct validated assignments for 64 samples were obtained. Different artificial mixtures ofolive−hazelnut, olive−corn, olive−sunflower, and olive−soybean oils were prepared and analyzedby 1H NMR and 31P NMR spectroscopy. Subsequent discriminant analysis of the data allowed detectionof adulteration as low as 5% w/w, provided that fresh virgin olive oil samples were used, as reflectedby their high 1,2-diglycerides to total diglycerides ratio (D ≥ 0.90). Keywords: 1H NMR and 31P NMR spectroscopy; vegetable oils; discriminant analysis; adulteration ofolive oil
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