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Giacalone R.,Italian Customs and Monopolies Agency | Giuliano S.,Italian Customs and Monopolies Agency | Gulotta E.,Italian Customs and Monopolies Agency | Monfreda M.,Italian Customs and Monopolies Agency | Presti G.,Italian Customs and Monopolies Agency
Food Chemistry | Year: 2015

In this study extra virgin olive oils of Italian and non-Italian origin (from Spain, Tunisia and blends of EU origin) were differentiated by GC-FID analysis of sterols and esterified sterols followed by chemometric tools. PCA allowed to highlight the high significance of esterified sterols to characterise extra virgin olive oils in relation to their origin. SIMCA provided a sensitivity and specificity of 94.39% and 91.59% respectively; furthermore, an external set of 54 extra virgin olive oils bearing a designation of Italian origin on the labelling was tested by SIMCA. Prediction results were also compared with organoleptic assessment. Finally, the poor correlation found between ethylesters and esterified sterols allowed to hazard the guess, worthy of further investigations, that esterified sterols may prove to be promising in studies of geographical discrimination: indeed they appear to be independent of those factors causing the formation of ethyl esters and related to olive oil production. © 2015 Elsevier Ltd. All rights reserved.

Monfreda M.,Italian Customs and Monopolies Agency | Varani F.,Italian Customs and Monopolies Agency | Cattaruzza F.,Italian Customs and Monopolies Agency | Ciambrone S.,Italian Customs and Monopolies Agency | Proposito A.,Italian Customs and Monopolies Agency
Science and Justice | Year: 2015

In this study, samples coming from large seizures of cocaine which took place in Italian Customs areas during 2011 and 2012 were examined. Minor alkaloids and residual solvents, analyzed by gas chromatography-mass spectrometry (GC-MS) and head space (HS)-GC-MS, respectively, were processed by principal component analysis (PCA), highlighting groupings of samples according to their chemical similarity. A hypothesis about the geographical origin of samples was also provided: most of them were compatible with Colombia as country of origin.Results of these analyses were used as starting point for the development of a "fast profiling" method, based on Fourier transform infrared spectroscopy (FTIR) and chemometric tools. Two models were developed and compared: KBr-FTIR and attenuated total reflection (ATR)-FTIR for comparative analysis of pure samples. Linear discriminant analysis (LDA) was applied to the model based on ATR-FTIR spectroscopy, obtaining a classification and a prediction ability both of 97.56% for pure samples. Finally, "cut" samples were tested as an external test set, and the assignment class provided by LDA was compared with results obtained by the analyses of alkaloids and residual solvents: in the case of samples added with only one substance, prediction errors began to occur for percentages of cocaine lower than 50%. © 2015 The Chartered Society of Forensic Sciences.

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