High-power gradient diffusion NMR spectroscopy for the rapid assessment of extra-virgin olive oil adulteration

Abstract A high gradient diffusion NMR spectroscopy was applied to measure diffusion coefficients ( D ) of a number of extra-virgin olive, seed, and nut oils in order to ascertain the suitability of this rapid and direct method for discrimination of adulterated olive oils. Minimum adulteration levels that could be detected by changes in D were 10% for sunflower (SuO) and soybean oil (SoO), and 30% for hazelnut (HO) and peanut oil (PO). Qualitative and quantitative prediction of adulteration was achieved by discriminant analysis (DA). The highest prediction accuracy (98–100%) was observed only when two DA models were concomitantly used for sample classification. The first DA model provided recognition of high adulterated EVOO with more than 20% of SuO or SoO, and 30% with PO, whilst the second model could differentiate EVOO adulterated with 10% of SuO or SoO, and more than 30% of HO. The validation test performed with an independent set of randomly adulterated EVOO samples gave 100% classification success. The high accuracy levels together with minimal requirements of sample preparation, and short analyses time, prove the high-power gradient diffusion NMR spectroscopy as an ideal method for rapid screening of adulteration in valuable olive oils.

[1]  M. Dennis,et al.  An introduction to food authentication , 1996 .

[2]  P. Barone,et al.  A High-Field 1H Nuclear Magnetic Resonance Study of the Minor Components in Virgin Olive Oils , 2022 .

[3]  Yukihiro Ozaki,et al.  The Detection and Quantification of Adulteration in Olive Oil by Near-Infrared Spectroscopy and Chemometrics , 2004, Analytical sciences : the international journal of the Japan Society for Analytical Chemistry.

[4]  Apostolos Spyros,et al.  Detection of extra virgin olive oil adulteration with lampante olive oil and refined olive oil using nuclear magnetic resonance spectroscopy and multivariate statistical analysis. , 2005, Journal of agricultural and food chemistry.

[5]  Royston Goodacre,et al.  Rapid quantitative assessment of the adulteration of virgin olive oils with hazelnut oils using Raman spectroscopy and chemometrics. , 2003, Journal of agricultural and food chemistry.

[6]  Da-Wen Sun,et al.  Modern Techniques for Food Authentication , 2008 .

[7]  P. Barone,et al.  A high-field1H nuclear magnetic resonance study of the minor components in virgin olive oils , 1996 .

[8]  Nerea Cabo,et al.  Infrared spectroscopy in the study of edible oils and fats , 1997 .

[9]  Richard G. Brereton,et al.  Chemometrics: Data Analysis for the Laboratory and Chemical Plant , 2003 .

[10]  Károly Héberger,et al.  Classification of olive oils using high throughput flow 1H NMR fingerprinting with principal component analysis, linear discriminant analysis and probabilistic neural networks , 2005 .

[11]  D. L. García-González,et al.  Detection of the presence of refined hazelnut oil in refined olive oil by fluorescence spectroscopy. , 2007, Journal of agricultural and food chemistry.

[12]  Apostolos Spyros,et al.  Classification of edible oils by employing 31P and 1H NMR spectroscopy in combination with multivariate statistical analysis. A proposal for the detection of seed oil adulteration in virgin olive oils. , 2003, Journal of agricultural and food chemistry.

[13]  Dimitrios Boskou,et al.  Olive oil: chemistry and technology. , 2006 .

[14]  L. Mannina,et al.  Olive oil as seen by NMR and chemometrics , 2003 .

[15]  J. Harwood,et al.  Nutritional and health aspects of olive oil , 2002 .

[16]  Francesco Addeo,et al.  1H and 13C NMR of virgin olive oil. An overview , 1997 .

[17]  F. L. Hart,et al.  Oils and Fats , 1971 .

[18]  N. Vlachos,et al.  Applications of Fourier transform-infrared spectroscopy to edible oils. , 2006, Analytica chimica acta.

[19]  George A. Mousdis,et al.  Rapid synchronous fluorescence method for virgin olive oil adulteration assessment , 2007 .

[20]  R. Reiners,et al.  Oils and fats , 1955 .

[21]  R. Aparicio,et al.  Authentication of vegetable oils by chromatographic techniques. , 2000, Journal of chromatography. A.

[22]  Dimitrios Boskou,et al.  Olive Oil Composition , 2006 .

[23]  Ricard Boqué,et al.  Rapid detection of olive–pomace oil adulteration in extra virgin olive oils from the protected denomination of origin “Siurana” using excitation–emission fluorescence spectroscopy and three-way methods of analysis , 2005 .

[24]  I. Wesley,et al.  Measurement of adulteration of olive oils by near-infrared spectroscopy , 1995 .

[25]  F. Reniero,et al.  1H NMR as a tool for the analysis of mixtures of virgin olive oil with oils of different botanical origin , 2000 .