Application of a multidisciplinary approach for the evaluation of traceability of extra virgin olive oil

In this work, a multidisciplinary approach for the evaluation of extra virgin olive oil traceability (geographical provenience and botanical differentiation) is presented. Conventional techniques such as major chemical component determination (triacylglycerols, TAG and fatty acids) and other novel approaches as stable isotopic ratio (13C/12C in combination with 18O/16O) and thermal properties obtained from cooling curves and their deconvoluted peaks by means of differential scanning calorimetry were compared. Fifty-three samples from different Italian regions, diverse cultivars, and two Mediterranean areas (Italy and Croatia) were analyzed with all the three techniques. The oils exhibited different values especially for δ18O and thermal properties of the deconvoluted peaks of crystallization according to Italian regions and/or cultivars. Data were treated by means of linear discriminant analysis inserting all parameters as predictors in models where the potentiality to discriminate oils was tested. All models revealed a good resolution among categories with selected TAG, δ18O values, and thermal properties of the deconvoluted peak set at the highest temperature exhibiting the highest weight for the discriminant functions. These findings could give strength to the utilization of new analytical techniques supporting those traditionally employed, also sustained by proper chemometric procedures, as suitable for the resolution of extra virgin olive traceability. Practical applications: Consumers' awareness of extra virgin olive oil traceability has recently increased the interest for new methods that can assess its geographical and botanical origins and new findings in this sector represent a key factor affecting the purchases in non-producer countries. Multidisciplinary approaches supported by chemometric procedures enable the building of large databases and classification models for the determination of the provenience of extra virgin olive oil.

[1]  E. Chiavaro,et al.  Chemical and thermal characterization of Tunisian extra virgin olive oil from Chetoui and Chemlali cultivars and different geographical origin , 2009 .

[2]  D. Kell,et al.  Chemometric criteria for the characterisation of Italian Protected Denomination of Origin (DOP) olive oils from their metabolic profiles , 2001 .

[3]  Carmen García-Ruiz,et al.  Traceability markers to the botanical origin in olive oils. , 2010, Journal of agricultural and food chemistry.

[4]  Elena Vittadini,et al.  Differential scanning calorimeter application to the detectionof refined hazelnut oil in extra virgin olive oil. , 2008, Food chemistry.

[5]  R. Larcher,et al.  Coast and year effect on H, O and C stable isotope ratios of Tyrrhenian and Adriatic Italian olive oils. , 2009, Rapid communications in mass spectrometry : RCM.

[6]  J. Ehleringer,et al.  Treatment methods for the determination of δ2H and δ18O of hair keratin by continuous‐flow isotope‐ratio mass spectrometry , 2005 .

[7]  P. Iacumin,et al.  Climatic factors influencing the isotope composition of Italian olive oils and geographic characterisation. , 2009, Rapid communications in mass spectrometry : RCM.

[8]  C. P. Tan,et al.  Comparative differential scanning calorimetric analysis of vegetable oils: I. Effects of heating rate variation. , 2002, Phytochemical analysis : PCA.

[9]  Gerard Downey,et al.  Confirmation of food origin claims by fourier transform infrared spectroscopy and chemometrics: extra virgin olive oil from Liguria. , 2009, Journal of agricultural and food chemistry.

[10]  C. P. Tan,et al.  Differential scanning calorimetric analysis of edible oils: Comparison of thermal properties and chemical composition , 2000 .

[11]  E. Chiavaro,et al.  Differential scanning calorimetry thermal properties and oxidative stability indices of microwave heated extra virgin olive oils. , 2011, Journal of the science of food and agriculture.

[12]  J. Giacometti,et al.  Composition and qualitative characteristics of virgin olive oils produced in northern Adriatic region, Republic of Croatia , 2001 .

[13]  E. Chiavaro,et al.  Differential scanning calorimetry: a potential tool for discrimination of olive oil commercial categories. , 2008, Analytica chimica acta.

[14]  M. Selva,et al.  Characterization of Almond Cultivars by the Use of Thermal Analysis Techniques. Application to Cultivar Authenticity , 2011 .

[15]  J. Durbec,et al.  Triacylglycerol and fatty acid compositions of French virgin olive oils. Characterization by chemometrics. , 2003, Journal of agricultural and food chemistry.

[16]  F. Reniero,et al.  Application of stable isotope ratio analysis to the characterization of the geographical origin of olive oils. , 1999, Journal of agricultural and food chemistry.

[17]  Lorenzo Cerretani,et al.  Preliminary characterisation of virgin olive oils obtained from different cultivars in Sardinia , 2006 .

[18]  F. Marini,et al.  NMR and chemometrics in tracing European olive oils: the case study of Ligurian samples. , 2010, Talanta.

[19]  Francesco M. Bucarelli,et al.  NMR and statistical study of olive oils from Lazio: A geographical, ecological and agronomic characterization , 2007 .

[20]  Monica Casale,et al.  The potential of coupling information using three analytical techniques for identifying the geographical origin of Liguria extra virgin olive oil , 2010 .

[21]  Lorenzo Cerretani,et al.  Application of partial least square regression to differential scanning calorimetry data for fatty acid quantitation in olive oil , 2011 .

[22]  R. Larcher,et al.  Characterisation of authentic Italian extra-virgin olive oils by stable isotope ratios of C, O and H and mineral composition , 2010 .

[23]  E. Chiavaro,et al.  Correlation between thermal properties and chemical composition of Italian virgin olive oils , 2010 .

[24]  D. L. García-González,et al.  Research in olive oil: challenges for the near future. , 2010, Journal of agricultural and food chemistry.

[25]  Ramón Aparicio,et al.  Stepwise geographical traceability of virgin olive oils by chemical profiles using artificial neural network models , 2009 .

[26]  P. Iacumin,et al.  Continuous-flow delta18O measurements: new approach to standardization, high-temperature thermodynamic and sulfate analysis. , 2005, Rapid communications in mass spectrometry : RCM.