Analytical insights for ensuring authenticity of Greek agriculture products: Unveiling chemical marker applications.

Food authentication, including the differentiation of geographical or botanical origin, the method of production i.e. organic vs. conventional farming as well as the detection of food fraud/adulteration, has been a rapidly growing field over the past two decades due to increasing public awareness regarding food quality and safety, nutrition, and health. Concerned parties include consumers, producers, and legislators. Thus, the development of rapid, accurate, sensitive, and reproducible analytical methods to guarantee the authenticity of foods is of primary interest to scientists and technologists. The aim of the present article is to summarize research work carried out on the authentication of Greek agricultural products using spectroscopic (NIR, FTIR, UV-Vis, Raman and fluorescence spectroscopy, NMR, IRMS, ICP-OES, ICP-MS) and chromatographic (GC, GC/MS, HPLC, HPLC/MS, etc.) methods of analysis in combination with chemometrics highlighting the chemical markers that enable product authentication. The review identified a large number of chemical markers including volatiles, phenolic substances, natural pigments, elements, isotopes, etc. which can be used for (i) the differentiation of botanical/geographical origin; conventional from organic farming; production procedure and vintage year, etc. and (ii) detection of adulteration of high quality plant and animal origin foods with lower value substitutes. Finally, the constant development of reliable analytical techniques in combination with law enforcement authorities will ensure authentic foods in terms of quality and safety for consumers.

Application of an ultra-performance liquid chromatography-tandem mass spectrometric method for the detection and quantification of cannabis in cerumen samples.

In this study, cerumen, a non-conventional biological secretion, was examined as an alternative matrix for forensic analyzis. A fully validated analytical UPLC-MS/MS method was developed for the detection and quantification of the most prevalent psychoactive illicit drug globe wide, Δ9-tethrahydrocannabinol, commonly known as THC, and four major cannabinoids found in cannabis Sativa. The method was validated, and standard external calibration curves were established with correlation coefficients > 0.99. A validated experimental procedure, along with a direct extraction of cannabinoids with acidified acetonitrile resulted in a short total analyzis time and a good extraction efficiency for all the analytes under study. LOD and LOQ values were determined to be 0.01-0.08 pg/mg and 0.04-0.23 pg/mg, respectively. To prove applicability of the proposed assay, volunteers were selected, and cerumen samples were examined for cannabis. The analyzis by use of UPLC-MS/MS indicated that all samples were positive, reporting recent cannabis abuse. Surprisingly, both THC and Cannabinol (CBN) were detected, and quantification was possible in 75% of the cases.

Physicochemical, Spectroscopic, and Chromatographic Analyses in Combination with Chemometrics for the Discrimination of the Geographical Origin of Greek Graviera Cheeses.

Seventy-eight graviera cheese samples produced in five different regions of Greece were characterized and discriminated according to geographical origin. For the above purpose, pH, titratable acidity (TA), NaCl, proteins, fat on a dry weight basis, ash, fatty acid composition, volatile compounds, and minerals were determined. Both multivariate analysis of variance (MANOVA) and linear discriminant analysis (LDA) were applied to experimental data to achieve sample geographical discrimination. The results showed that the combination of fatty acid composition plus minerals provided a correct classification rate of 89.7%. The value for the combination of fatty acid compositions plus conventional quality parameters was 94.9% and for the combination of minerals plus conventional quality parameters was 97.4%. When cheeses of the above five geographical origins were combined with previously studied graviera cheeses from six other geographical origins collected during the same seasons in Greece, the respective values for the discrimination of geographical origin of all eleven origins were 89.3% for conventional quality parameters plus minerals; 94.0% for conventional quality parameters plus fatty acids; 94.1% for minerals plus fatty acids; and 95.2% for conventional quality parameters plus minerals plus fatty acids. Such high correct classification rates demonstrate the robustness of the developed statistical model.

Characterization and Botanical Differentiation of Monofloral and Multifloral Honeys Produced in Cyprus, Greece, and Egypt Using Physicochemical Parameter Analysis and Mineral Content in Conjunction with Supervised Statistical Techniques.

Thirty-four honey samples donated by beekeepers and purchased from supermarkets were collected during harvesting years 2010-2014 from Cyprus, Greece, and Egypt. The aims of this study were to characterize honey samples and, if possible, to differentiate honeys according to the honey type on the basis of physicochemical parameter values, mineral content, and their combination using supervised statistical techniques (linear discriminant analysis (LDA)). Physicochemical parameters (colour, pH, free acidity, total dissolved solids, salinity, electrical conductivity, and moisture content) were determined according to official methods, while minerals (Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Ni, P, Pb, Sb, Si, Ti, Tl, V, and Zn) using inductively coupled plasma optical emission spectrometry. The majority of honey samples analyzed met the quality criteria set by the European directive and national decision related to honey. Implementation of multivariate analysis of variance (MANOVA) and LDA on specific physicochemical parameters, minerals, or their combination provided a satisfactory classification of honeys according to floral type. The overall correct classification rate (based on the cross-validation method) was 79.4% using 7 minerals and 91.2% using 8 physicochemical parameters. When the 15 parameters were combined, the classification rate of Egyptian honeys was improved by 25%.

Characterization and geographical discrimination of commercial Citrus spp. honeys produced in different Mediterranean countries based on minerals, volatile compounds and physicochemical parameters, using chemometrics.

The objective of the present study was: i) to characterize Mediterranean citrus honeys based on conventional physicochemical parameter values, volatile compounds, and mineral content ii) to investigate the potential of above parameters to differentiate citrus honeys according to geographical origin using chemometrics. Thus, 37 citrus honey samples were collected during harvesting periods 2013 and 2014 from Greece, Egypt, Morocco, and Spain. Conventional physicochemical and CIELAB colour parameters were determined using official methods of analysis and the Commission Internationale de l' Eclairage recommendations, respectively. Minerals were determined using ICP-OES and volatiles using SPME-GC/MS. Results showed that honey samples analyzed, met the standard quality criteria set by the EU and were successfully classified according to geographical origin. Correct classification rates were 97.3% using 8 physicochemical parameter values, 86.5% using 15 volatile compound data and 83.8% using 13 minerals.

Determination of okadaic acid, dinophysistoxin-1 and related esters in Greek mussels using HPLC with fluorometric detection, LC-MS/MS and mouse bioassay.

An approach involving both chemical and biological methods was undertaken for the detection and quantification of the marine toxins okadaic acid (OA), dinophysistoxin-1 (DTX-1) and their respective esters in mussels from different sampling sites in Greece during the period 2006-2007. Samples were analyzed by means of a) high performance liquid chromatography with fluorometric detection (HPLC-FLD), using 9-athryldiazomethane (ADAM), as a pre-column derivatization reagent, b) liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) and c) the mouse bioassay. Free OA and DTX-1 were determined by both HPLC-FLD and LC-MS/MS, while their respective esters were determined only by LC-MS/MS after alkaline hydrolysis of the samples. The detection limit (L.O.D.) and quantification limit (L.O.Q.) of the HPLC-FLD method were 0.015 microg/g HP and 0.050 microg/g HP, respectively, for OA. The detection limit (L.O.D.) and quantification limit (L.O.Q.) of the LC-MS/MS method were 0.045 microg/g HP and 0.135 microg/g HP, respectively, for OA. Comparison of results between the two analytical methods showed excellent agreement (100%), while both HPLC-FLD and LC-MS/MS methods showed an agreement of 97.1% compared to the mouse bioassay.