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High Performance Liquid Chromatography (HPLC) with diode array (DAD) and fluorescence (FLD) detection was used to acquire the fingerprints of the phenolic fraction of monovarietal extra-virgin olive oils (extra-VOOs) collected over three consecutive crop seasons (2011/2012-2013/2014). The chromatographic fingerprints of 140 extra-VOO samples processed from olive fruits of seven olive varieties, were recorded and statistically treated for varietal authentication purposes. First, DAD and FLD chromatographic-fingerprint datasets were separately processed and, subsequently, were joined using "Low-level" and "Mid-Level" data fusion methods. After the preliminary examination by principal component analysis (PCA), three supervised pattern recognition techniques, Partial Least Squares Discriminant Analysis (PLS-DA), Soft Independent Modeling of Class Analogies (SIMCA) and K-Nearest Neighbors (k-NN) were applied to the four chromatographic-fingerprinting matrices. The classification models built were very sensitive and selective, showing considerably good recognition and prediction abilities. The combination "chromatographic dataset+chemometric technique" allowing the most accurate classification for each monovarietal extra-VOO was highlighted., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Olive oil phenolic fraction considerably contributes to the sensory quality and nutritional value of this foodstuff. Herein, the phenolic fraction of 203 olive oil samples extracted from fruits of four autochthonous Moroccan cultivars ("Picholine Marocaine", "Dahbia", "Haouzia" and "Menara"), and nine Mediterranean varieties recently introduced in Morocco ("Arbequina", "Arbosana", "Cornicabra", "Frantoio", "Hojiblanca", "Koroneiki", "Manzanilla", "Picholine de Languedoc" and "Picual"), were explored over two consecutive crop seasons (2012/2013 and 2013/2014) by using liquid chromatography-mass spectrometry. A total of 32 phenolic compounds (and quinic acid), belonging to five chemical classes (secoiridoids, simple phenols, flavonoids, lignans and phenolic acids) were identified and quantified. Phenolic profiling revealed that the determined phenolic compounds showed variety-dependent levels, being, at the same time, significantly affected by the crop season. Moreover, based on the obtained phenolic composition and chemometric linear discriminant analysis, statistical models were obtained allowing a very satisfactory classification and prediction of the varietal origin of the studied oils. [ABSTRACT FROM AUTHOR]

The triacylglycerols composition of monovarietal Picholine Marocaine olive oils, produced in seven of the most productive areas in northern Morocco, has been established for the first time, starting a register of typicality and geographical identity of Moroccan olive oils. Two hundred seventy-nine olive samples were collected over two consecutive crop seasons (2011/2012 ( n = 140) and 2012/2013 ( n = 139)), the analysis of the triacylglycerol profiles of the obtained oils was performed using high performance liquid chromatography, the influence of the region of provenance was investigated, and chemometric data analysis (including principal components analysis, linear discriminant analysis, partial least squares-discriminant analysis, and soft independent modeling of class analogies) was used to differentiate the studied samples according to their geographical origin. Twenty-one triacylglycerols were characterized and the variability observed among the studied samples could be related to the production area. The combination of triacylglycerols composition with chemometrics provided a powerful tool to verify the geographical origin of north Moroccan olive oils. Practical applications: Moroccan legislations established Geographic Indication labels for adding value to typical products. However, the general procedure to control the geographical authenticity of these protected products remains based on the traceability of their production and there is a lack of appropriate and reliable tools for their geographical unambiguous authentication and control. In this work, geographical authentication models for classifying olive oil samples (based on triacylglycerols composition) have been developed and evaluated, achieving adequate classification and prediction rates for oils coming from the main north Moroccan olive growing areas. The results obtained herein, could represent a significant contribution to the control of the geographical authenticity of Moroccan olive oils. The triacylglycerols composition of monovarietal Picholine Marocaine olive oils, from seven of the most productive areas in northern Morocco, is established in this study, analyzing 279 olive samples (over two consecutive crop seasons) by high performance liquid chromatography and Chemometrics. [ABSTRACT FROM AUTHOR]

Herewith, the potential of an approach based on the combination of the determination of phenolic compounds and the use of chemometric treatments has been evaluated to establish, for the first time, promising models to authenticate the provenance of Moroccan monovarietal olive oils produced under different geographical origin indication systems. To achieve this purpose, 136 commercial extra virgin olive oil samples from three diverse production areas (Meknès territory; the Protected Geographical Indication Ouazzane; and the Protected Designation of Origin Tyout-Chiadma) were collected over two consecutive crop seasons (2012/2013 and 2013/2014). Their phenolic fraction composition was investigated by using high performance liquid chromatography coupled to mass spectrometry (HPLC-ESI-IT MS). The results showed that geographical provenance and harvest season had a marked influence on the content of identified phenolic compounds. Principal components analysis (PCA) and linear discriminant analysis (LDA) were applied to test the potential of the determined compounds as geographical discriminant features, achieving a noticeable discrimination among the three evaluated regions. The contribution of each analyte to the statistic model has been evaluated in depth. [ABSTRACT FROM AUTHOR]

Selected Ion flow tube mass spectrometry (SIFT-MS) in combination with chemometrics was used to authenticate the geographical origin of Mediterranean virgin olive oils (VOOs) produced under geographical origin labels. In particular, 130 oil samples from six different Mediterranean regions (Kalamata (Greece); Toscana (Italy); Meknès and Tyout (Morocco); and Priego de Córdoba and Baena (Spain)) were considered. The headspace volatile fingerprints were measured by SIFT-MS in full scan with H 3 O + , NO + and O 2 + as precursor ions and the results were subjected to chemometric treatments. Principal Component Analysis (PCA) was used for preliminary multivariate data analysis and Partial Least Squares-Discriminant Analysis (PLS-DA) was applied to build different models (considering the three reagent ions) to classify samples according to the country of origin and regions (within the same country). The multi-class PLS-DA models showed very good performance in terms of fitting accuracy (98.90–100%) and prediction accuracy (96.70–100% accuracy for cross validation and 97.30–100% accuracy for external validation (test set)). Considering the two-class PLS-DA models, the one for the Spanish samples showed 100% sensitivity, specificity and accuracy in calibration, cross validation and external validation; the model for Moroccan oils also showed very satisfactory results (with perfect scores for almost every parameter in all the cases). [ABSTRACT FROM AUTHOR]

Herewith we have evaluated the variability of the composition in terms of volatile compounds of monovarietal “ Picholine marocaine ” olive oils and checked the possible influence of their geographical origin. For this purpose, 92 olive samples were collected during the harvesting period 2012/2013 from 7 north Moroccan regions, and the analysis of the volatile profiles of the obtained oils was performed by using headspace solid-phase microextraction coupled to gas chromatography with flame ionization and mass spectrometry detectors (HS-SPME/GC-FID–MS). A total of 40 volatile compounds belonging to different chemical classes were identified and quantified. Significant differences in the concentration levels of volatile constituents from oils of different geographical origins were found. Furthermore, for testing the ability of the identified volatile compounds for the geographical origin discrimination of the investigated oils, a stepwise linear discriminant analysis (s-LDA) was applied. Results revealed a very satisfactory classification of the studied oils according their geographic origin. [ABSTRACT FROM AUTHOR]

Current knowledge of the quality and composition of Moroccan olive oil is still incomplete and no consistent database compiling its properties is available. This study was carried out to achieve a comprehensive characterisation of north Moroccan olive oils. Thus, 279 olive samples of “ Picholine Marocaine ” cultivar grown in 7 Moroccan regions were collected, and oils extracted over two consecutive crop seasons (2011 and 2012) and analysed (considering physicochemical quality parameters and purity criteria). Results indicated that all the studied samples showed values fulfilling the established limits set by the International Olive Council (IOC) standards, with the exception of 32 samples that had a linolenic acid content higher than 1%, which is the maximum value fixed by the IOC regulation. Furthermore, the usefulness of the evaluated parameters for tracing the geographical origin of the studied samples was tested by using canonical discriminant analysis. A good rate of correct classification and prediction was achieved. [ABSTRACT FROM AUTHOR]

The applicability of two different platforms (LC-ESI-TOF MS and LC-ESI-IT MS) as powerful tools for the characterisation and subsequent quantification of the phenolic compounds present in north Moroccan virgin olive oils was assessed in this study. 156 olives samples of "Picholine Marocaine" cultivar grown in 7 Moroccan regions were collected and olive oils extracted. The phenolic profiles of these olive oils were studied using a resolutive chromatographic method coupled to ESI-TOF MS (for initial characterisation purposes) and coupled to ESI-IT MS (for further identification and quantification). 25 phenolic compounds belonging to different chemical families were identified and quantified. Secoiridoids were the most abundant phenols in all the samples, followed by phenolic alcohols, lignans and flavonoids, respectively. For testing the ability of phenolic profiles for tracing the geographical origin of the investigated oils, multivariate analysis tools were used, getting a good rate of correct classification and prediction by using a cross validation procedure. [ABSTRACT FROM AUTHOR]

Protected designations of origin (PDO) constitute, nowadays, one of the most important differentiation strategies used for the promotion and commercialization of virgin olive oil (VOO). Obtaining these distinctive labels entails a deep study of the inherent features and characteristics of a VOO linked to a given geographical production area. The aim of this study was to perform the physicochemical and sensorial quality characterization of Meknès VOO, as well as the determination of its compositional profile. Thus, a total of 298 olive oil samples from Picholine marocaine cultivar, obtained from 12 industrial olive oil mills, located in three sub-areas of Meknès region, were analyzed over four consecutive seasons, paying particular attention to the determination of physicochemical quality indices, sensorial evaluation, total phenol content, pigment content, tocopherol and fatty acid composition. Results show that, besides an interannual variation, VOOs from Meknès region are characterized by high physicochemical and sensory quality, as well as a homogeneous composition regardless of the production sub-area. [ABSTRACT FROM AUTHOR]