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Metal ions with smaller radii than Pb2+ can stabilize CsPbBr3 NCs' cubic structure by lattice shrinkage, but lacking sensing research. Herein, Ni-substituting CsPbBr3 NCs were prepared to rapidly and accurately detect water content (WC) in edible oils. CsPb0.95Ni0.05Br3 NCs had the highest fluorescence intensity, approximately 125 % of CsPbBr3 NCs. The results displayed that CsPb0.95Ni0.05Br3 NCs were uniformly quadrilateral crystalline packing (8.78 ± 0.28 nm particle size) with inter-planar distances of 0.41, 0.33, and 0.29 nm. Given the fluorescence quenching behavior, a superior linear curve between fluorescence-decreased ratio and WC was established within 0–3 ‰ (v/v) and a detection limitation of 0.042 ‰. Furthermore, excellent precision and accuracy were verified in various oils with a relative error of 2.06 %. It was suggested that water destroyed and dissolved CsPb0.95Ni0.05Br3 NCs' crystal structure to induce fluorescence quenching. Thus, Pb-site substitutions of CsPbBr3 NCs enhanced the sensing performance, enlightening other elements-substituted CsPbBr3 NCs for sensing.

Exploring natural antioxidants is essential to delay lipid oxidation. This study investigated the inhibitory effect of Adinandra nitida (AN) extract in six edible oils, compared to TP and TBHQ. Methods included extract preparation, bioactive compounds analysis, in vitro antioxidant activities by FRAP, DPPH, and ABTS assays, fatty acid composition detection, and POV determination. The results showed that AN was rich in total flavonoids, total phenols and had better iron ion reduction ability than TBHQ. In oleic and linoleic acid-rich oils, AN significantly delayed early-stage lipid oxidation, outperforming TP and TBHQ. In linolenic acid-rich oils, AN maintained a stable effect. Molecular docking studies revealed strong binding interactions between main compounds and fatty acids, with Camelliaside A in (7.83) showing higher binding energy to linolenic acid than TBHQ (7.64), supporting the antioxidant effects. These findings suggest AN as a promising natural alternative to synthetic antioxidants, enhancing oil stability and shelf life.

The current study assessed the hypolipidemic effect and modulation of hepatic enzymes by different edible oils in obese Wistar rats. In order to conduct this study, 36 Wistar rats that were collected at 5 weeks of age and weighed an average of 70 g were split into two groups: 28 of them were fed a high-fat diet (HFD) and 8 of them were fed a control diet. After 5 weeks of feeding, rats from the HFD (obese, n = 4) and the control diet group (n = 4) were sacrificed. Subsequently, the rest of obese rats (n = 24) were separated into six groups, including the continuing high-fat (CHF) diet group, rice bran oil (RBO) diet group, olive oil (OO) diet group, soybean oil (SO) diet group, cod liver oil (CLO) diet group, and sunflower oil (SFO) diet group, and the continuing control diet group (n = 4). Rats from each group were sacrificed following an additional 5 weeks, and all analytical tests were carried out. The results found that the interventions of RBO, CLO, and SFO in obese rats reduced their body weight non-significantly when compared with CHF. It was also observed that a non-significant reduction in weight of the heart, AAT, and EAT occurred by RBO, OO, SO, and CLO, while SFO reduced the AAT level significantly (p

Population growth has made it difficult to provide safe food; because various toxic substances such as polychlorinated biphenyls (PCBs) can contaminate food products such as edible oils which have very high-rate consumption worldwide. Aims of study are to determine the concentration of PCBs in edible oil samples and to evaluate the carcinogenic risk of PCBs in them among Iranian people by Monte Calo Simulation (MCS). After finding the location of high customer hyper market in Tehran, 42 samples of 7 various types of edible oils were collected; then PCBs content of them measured using the modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) extraction method and GC/MS technique. According to the findings the mean level of NDL-PCB in oil samples were ranged from 1.88 to 25.62 ng/g fat. Results of uncertainty analysis showed that among children the 95th percentile of Incremental Lifetime Cancer Risk (ILCR) were 7.80E-3, 5.37E-4, 5.37E-4, 2.00E-3, 1.59E-3, 13.9E-3 and 7.04E-4 for animal oil, corn oil, frying oil, olive oil, bran oil, sesame oil and sunflower oil, respectively. Also, the 95th percentile of ILCR among adults were 4.12E-2, 3.04E-3, 3.09E-3, 1.06E-2, 8.43E-3, 7.38E-3 and 3.74E-3 for animal oil, corn oil, frying oil, olive oil, bran oil, sesame oil and sunflower oil, respectively. The risk evaluation showed that in all edible oils the 95th percentile of simulated ILCR were more than 10−5, so it can be threatening health among both aging groups, although, the producers don't deliberately subject the users' lives to such danger, but high consumption rate and accumulation of PCBs in body tissues are contribute to increasing carcinogenic risk. Also, the 95th percentile of ILCR among adults were more than children, because the edible oil ingestion rate among adults was more than children.

In this study, a new method was used to evaluate the levels of four organochlorine pesticides in edible samples. In this method, a density tunable dispersive solid phase extraction procedure was coupled with gas chromatography-mass spectrometry. Rhodamine B was used as a sorbent, which was distributed throughout the oil matrix with the aid of evaporation of methanol. This process enabled the possibility of effective extraction and preconcentration of the target analytes. To achieve this goal, several factors affecting the extraction efficiency, including the type and volume of diluent, the amount of rhodamine B, the volume of methanol, and the temperature of the ultrasonic bath were carefully evaluated. This method provided low detection limits (from 0.21 to 0.36 ng g -1 ), wide linear range (1.1-100 ng g -1 ) and acceptable extraction recoveries (64-72%) and enrichment factors (102-115). The precision of the method was evaluated by calculating the relative standard deviation, which ranged from 3.6 to 6.8% for intra- and 3.1 to 8.8% for inter-day precisions. The investigated method reduced the interference of the matrix and provided the possibility of quantitative determination of the studied organochlorine pesticides in various oil samples (canola, corn, sunflower, and olive). This method introduced a reliable analytical tool for the monitoring of the pesticide residues in different oil samples by providing capabilities such as simplicity, sensitivity, and compatibility with the environment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

In this work, a novel deep eutectic solvent (DES) composed of thymol and 1-(o Tolyl)thiourea 9/1 (mol) is presented for the first time. This DES has not been described in the literature. This DES was first used as a stationary phase in an extraction column integrated into a flow injection analysis system for the simultaneous determination of mercury and copper in edible oils. The automated approach involves passing an aqueous sample solution obtained after microwave mineralization through a microcolumn of DES retained on polytetrafluoroethylene. This leading to the extraction and concentration of the analytes. The metals are then eluted with an aqueous thiourea solution for subsequent analysis by inductively coupled plasma-optical emission spectrometry. The limits of detection (LODs) for mercury and copper were 3 μg L⁻ 1 and 2.5 μg L⁻ 1 , respectively. The approach demonstrated high accuracy. Relative standard deviations (RSD) for repeatability and inter-day reproducibility ranged from 3 % to 11 %. Extraction recovery of both metals exceeded 95 %, indicating the high efficiency of the DES-based extraction process. Environmental assessment using the AGREEprep method yielded a favorable environmental index of 0.54, highlighting the robustness of the approach. This novel use of DES as a stationary phase in flow injection analysis system provides a robust, efficient and environmentally friendly approach to the determination of trace metals in edible oils. This method can also be applied to the analysis of other samples., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

A novel simple, environmentally friendly and portable method to determine vitamin E in edible oils based on reversed-phase dispersive liquid-liquid microextraction combined with electrochemical detection using screen-printed carbon electrodes (SPCEs) has been developed. Vitamin E was extracted from oil samples into a 4 M HCl aqueous solution and determined by differential pulse voltammetry using SPCEs. The extraction conditions optimized by experimental design (i.e., Plackett–Burman and central composite designs) were: aqueous 4 M HCl extractant volume, 43 µL; extraction time, 2 min; centrifugation time, 10 min; and centrifugation speed, 3000 rpm. The proposed method requires a standard addition calibration approach, and the working range showed good linearity from 0 to 20 mg L−1, with a correlation coefficient ranging from 0.990 to 0.995 (N=5). The methodological limit of detection was between 1 and 3 mg L−1. The repeatability of the proposed method was evaluated at 15 mg L−1, and the relative standard deviation ranged between 10 and 15% (n=5). For the quantification of vitamin E in ten commercial samples of olive, sesame, soybean, sunflower and a mixture of sunflower and corn oils, the volume of the extractant phase (i.e., 4 M HCl aqueous solution) was increased up to 100 µL and satisfactory recoveries were obtained in the range of 85–115%, confirming the applicability of the method.

Sensitively, accurately, and rapidly evaluating edible oils' peroxide value (PV) is significant for safeguarding food quality and safety. However, the conventional detection methods are challenging to meet the above demands due to their complex operation, poor reproducibility, and professional personnel. The colorimetric method is an emerging technique to rapidly and on-site determine the PV of edible oils. CsPbBr 3 NCs, as a novel fluorescent-sensing material, have been applied in the chemical colorimetric analysis. However, the heavy use of high-toxic solvents (toluene, chloroform) in the CsPbBr 3 NCs colorimetric system significant-negatively influences the environment. This study evaluated the performances of CsPbBr 3 NCs in nine low-toxic solvents and investigated the potential response mechanism to PV. The results presented that CsPbBr 3 NCs in ethyl acetate displayed the highest photoluminescent intensity and the most uniform distribution. The results performed that the micro-morphology and crystal structure of CsPbBr 3 NCs in ethyl acetate were similar to that in toluene, demonstrating the potential excellent performance. Under optimum conditions, three methods, including photoluminescence (PL)-decreased, wavelength-shifted, and phone-based colorimetric methods, were established to evaluate PV with the LOD of 0.0034 g/100 g. The PV recovery rates in Soybean oil, Camellia oil, Linseed oil, and Olive oil were from 75.0% to 100.0%, with a relative error below 25%. Furthermore, it was believed that the decreased PL and shifted wavelength originated from the halogen substitution with the crystal-structure destructions and the surface-defect formations. Thus, developing the low-toxic colorimetric CsPbBr 3 NCs system with ethyl acetate could reduce the environmental influence and even enlighten the rise of other green detection methods for PV in edible oils., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or person al relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Tert-butylhydroquinone (TBHQ) is widely used to increase the stability of food products; however, it is considered to be a highly unsafe preservative ingredient that has caused serious damage to human health. Thus, in this paper, a novel molecularly imprinted electrochemical sensor was designed for ultrasensitive, and selective detection of TBHQ in edible oils. The sensor was based on the molecularly imprinted polymer (MIP) synthesized with multiwalled carbon nanotube (MWCNT), and gold nanoparticle (GNP), as the coating materials, o-phenylenediamine (o-PDA) as the functional monomer, and TBHQ as the template molecule. The electrochemical behavior of MIP/GNP/MWCNT/GCE was studied using several electrochemical methods, which showed a low detection limit of 5 nM. Furthermore the sensor demostrated excellent stability, selectivity, repeatability, and reproducibility. It was successfully used to detect TBHQ in edible oils, with recoveries ranging from 98.44% to 102.09% and relative standard deviations (RSDs) of less than 2.16%, indicating that TBHQ detection in actual samples is both possible and accurate., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Inc.)

Physicochemical properties like density, viscosity, boiling point, saponification value (SV), iodine value (IV),and peroxide value (PV) of Corn and Mustard oils were studied to evaluate the compositional quality of oils and also to investigate the effect on the use of same oil for repeated frying as it ultimately changes the physicochemical, nutritional and sensory properties of the oil. FT-IR spectroscopy was used to evaluate the degree of oxidation after heating and frying processes. Results revealed that due to the temperature change in the oil there is a notable difference in the spectral band which showed that the proportions of the fatty acids were changed. The spectra of Corn oil at the boiling point and at multiple frying times with a piece of potato showed frequencies in range of 2852.7–2926.0 cm−1 while in Mustard oil an additional peak was observed at 3633.8 cm−1 which exhibits the secondary oxidized product formation.

The development and validation of a method for the analysis of traces of 3-monochloropropanediol (3-MCPD) esters (19) and glycidyl esters (7) of fatty acids in vegetable oils, margarine, biscuits and croissants was performed. An extraction method based on the use of solvents (tert‑butyl methyl ether (20% ethyl acetate, v/v)) was carried out and cleaning of the extract with a mixture of sorbents (Si-SAX, PSA and Z-sep+) was optimized for the elimination of fatty interferents. The analysis of the targeted compounds was carried out by ultra-high-performance liquid chromatography coupled to tandem mass spectrometry, using a triple quadrupole analyzer (UHPLC-MS/MS-QqQ). The validation of the method provided trueness values between 72 and 118% and precision lower than 20%. The limits of quantification ranged from 0.01 to 0.1 mg kg -1 , which were below the current legal limits. Twenty samples of vegetable oils as well of 4 samples of margarine, biscuits and croissants were analyzed. Six out of the 24 samples (25%) exceeded the limits set by European legislation, and a maximum contamination of 3-MCPD esters at 2.52 mg kg -1 was obtained in a sample of corn oil (being 1-myristoyl-3-MCPD the compound detected at the highest concentration). A maximum concentration of glycidyl esters at 7.84 mg kg -1 was determined in a soybean oil sample (glycidyl linoleate as the main compound). Only one sample of olive oil exceeded the maximum allowable limit for 3-MCPD esters with a value of 1.72 mg kg -1 , expressed as 3-MCPD., Competing Interests: Declaration of Competing Interest The authors declare that there is no conflict of interest., (Copyright © 2021. Published by Elsevier B.V.)

Geographical discrimination and adulteration analysis play significant roles in edible oil analysis. A novel method for discrimination and adulteration analysis of edible oils were proposed in this study. The two-dimensional correlation spectra of edible oils were obtained by solvents perturbation and the convolutional neural networks (CNNs) were constructed to analyze the synchronous and asynchronous correlation spectra of the edible oils. The differences for geographical origins of oils or oil types could be amplificated through the networks. For different networks, the layer sequences and the filter number of convolutional layers may affect the analysis results. A group of sesame oils from different geographical origins and a group of olive oils adulterated by other vegetable oils were adopted to evaluate the proposed method. The results show that the proposed method may provide an alternative method for edible oil discrimination and adulteration analysis in practical applications. For the two datasets, the prediction accuracy could be 97.3% and 88.5%, respectively., Competing Interests: Declaration of competing interest The authors declared that they have no conflicts of interest to this work. We declare that we do not have any commercial or associative interest that represents a conflict of interest in connection with the work submitted., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A sample pretreatment based on an extraction process by emulsion breaking for multi-element determination in edible oils was developed. The determination of eight trace elements (Al, Ba, Cu, Cr, P, Ni, Ti, and Zn) was carried out by microwave-induced plasma optical emission spectrometry (MIP OES) after the extraction procedure. A D-optimal mixture experimental design was used to obtain the best experimental conditions for the extraction induced by emulsion breaking (EIEB). The proportion of HNO 3 solution, Triton X-100 solution and sample was evaluated in a multivariate manner. The best recovery efficiency was obtained with 1.0 mL of 30% (v/v) HNO 3 , 1.0 mL of 30% (w/v) Triton-X 100 and 3.0 mL of the sample. The precisions, established as the relative standard deviation (RSD, %), were better than 2.5% for all analytes. The developed method was applied to the analysis of commercial vegetable oils with low limits of detection and good precision., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Because of the important advantages as rapidity, cost effectiveness and no sample preparation necessity, encountered in most of the cases, Raman spectroscopy gained more and more attention during the last years with regard to its application in food and beverages authenticity. Vegetable cold-pressed oils obtained from: sesame, hemp, walnut, linseed, pumpkin and sea buckthorn have gained increased attention in consumer interest due to their high nutrient value and health benefits. The high commercial value of these, brought the temptation from some unfair producers and sellers to gain an illegal profit by replacing the raw material of these oils by cheaper ones (i.e. sunflower). Here a new approach based on the rapid processing of Raman spectra using Machine Learning algorithms, for edible oil authentication was developed and successfully tested. Through this approach, not only the adulteration detection was achieved but also an initial estimation of its magnitude., (Copyright © 2020 Elsevier B.V. All rights reserved.)

A comprehensive study concerning the characterization and classification of 30 cold-pressed edible oils according to their UV-Vis spectra and radical scavenging profiles using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay is presented. Considering the principal component analysis (PCA) and fuzzy-principal component analysis (FPCA) loadings profiles, the characteristic spectral regions with a significant influence in oil samples classification were identified and associated with characteristic factors in each group. Much more, the oils with high antiradical capacity were revealed. The scores corresponding to the first principal component and the canonical scores corresponding to the first discriminant function derived from radical scavenging spectral profiles allowed a relevant classification of oils in well-defined groups associated with their high, medium and low radical scavenging capacity. The FPCA-LDA method applied on DPPH radical scavenging spectral profiles of edible oils appeared to be the most efficient method with a correct classification rate of 96.7%., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This study presents the development and validation of a method for the multi-class multi-residue analysis of pesticide residues in edible oils using liquid-liquid extraction followed by EMR-Lipid (enhanced matrix removal - lipid) cartridge cleanup, and then analyzed by gas chromatography tandem mass spectrometer (GC-MS/MS). The method was optimized for analyte recovery, matrix removal, and water removal during the sample extraction, sample cleanup and sample drying steps. The extraction efficiency of lipophilic pesticides (i.e. organochlorine) from the hydrophobic oil matrix was improved using a two-step liquid-liquid extraction with a mixture of ethyl acetate and acetonitrile. EMR-Lipid cartridges provided efficient and selective cleanup of the tested oil matrices. The developed method was verified by analyzing four edible oil matrices: olive oil, corn oil, soybean oil and canola oil. The results demonstrated that the method effectively removes unwanted matrix co-extractives better than conventional PSA/C18 dispersive solid phase extraction (dSPE) cleanup, while still delivering acceptable recovery results (recoveries of 60-120%) for the majority of pesticides tested. With the established quantification method, over 95% of the pesticides obtained for 70-120% accuracy, RSD < 20%, and calibration curves from 1 to 500 (400) ng/g in oil with R 2 > 0.99., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Bioemulsifiers are able to stabilize oil-in-water emulsions and are very important in several industrial processes, including food processing. In this study, a bioemulsifier produced by Ensifer adhaerens JHT2 was tested for its ability to emulsify edible oils (canola, corn, palm, olive and soy). Emulsification of soy and canola oils was detected, but the highest emulsification index (EI) was obtained when JHT2 culture supernatant was used for the emulsification of palm oil (EI=100%). Bioemulsifier production was evaluated using nine culture media and different NaCl concentrations (0.5 to 10%), pH (4 to 10) and temperatures (28 to 42°C). The highest emulsification activity was detected in the supernatants of JHT2 grown in trypticase soy broth containing 0.5-1.0% NaCl, pH6-7 and temperatures of 28-37°C. Characterization of the bioemulsifier produced by JHT2 revealed typical characteristics of exopolysaccharides (EPS), constituting a backbone of (1→4)-β-d-glucopyranosyl and (1→3)-β-D-galactopyranosyl alternating with (1→4)-α-d-mannopyranosyl units that branch from the structure at O-2. Side chains are composed of units of (1→6)-β-d-glucopyranosyl and 3-O-linked galactopyranosyl bearing a pyruvic acid acetal substitution at O-4 and O-6. Our results indicate that the EPS produced by Ensifer adhaerens JHT2 is a promising option for improving and maintaining stable emulsions in food prepared with edible oils., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A fast and effective method using a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach which includes partitioned liquid-liquid extraction (PLLE) and dispersive solid phase extraction (dSPE) clean-up step for the determination of seven 3-monochloropropane-1,2-diol (3-MCPD) fatty acid diesters in vegetable oils is developed and validated according to the Food and Drug Administration (FDA) guidelines. Due to the complexity of the matrices, combination of silica based sorbents (Silica Strong Anion Exchange (Si-SAX), Supel™ QuE Z-Sep+ (Z-Sep+) and Primary Secondary Amine (PSA) were tested for lipid removal. The effect of several experimental factors on the efficiency of the extraction procedure was studied by a screening design 3 4 2 2 //16 and a response surface Doehlert design. The separation and determination was carried out by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The method provided suitable linearity (r 2  > 0.9960), precision (relative standard deviation (RSD) lower than 10%) and accuracy, in terms of recovery. The limits of detection (LOD) and limits of quantification (LOQ) ranged from 10 to 20 μg kg -1 and from 25 to 50 μg kg -1 , respectively. The recoveries at three spiking levels of 100, 250, and 500 μg kg -1 were over the range of 71.4-122.9% with RSD lower than 13%. The method was successfully applied in edible oils and fatty food samples. The results provide valuable information to assess the risk of exposure to these foodborne contaminants., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The effect of heating in twenty-four different oil samples was evaluated via iodine value (IV), gas chromatography (GC) and mid-infrared (MIR) analyses. Common components and specific weights analysis (CCSWA) was applied to distribute the samples according to their most relevant characteristics, thereby revealing the influence of heating on composition. Instrumental analysis indicated a high amount of beneficial fatty acids, such as alpha-linolenic acid, in less exploited oils such as chia oil. This oil can present nutritional damage when subjected to high temperatures and is thus less recommended for frying. Conversely, oils containing high amounts of linoleic acid, such as almond and nut oils, as well as those containing equivalent amounts of alpha-linolenic and linoleic acids, such as golden flaxseed and flaxseed oils, displayed greater resistance to temperature. The 3008/cm band exhibited greater intensity in oils with a higher degree of unsaturation, such as chia and linseed oils, a phenomenon mainly influenced by the presence of linoleic and alpha-linolenic fatty acids. After heating, there was a decrease in the intensity of this band. The main parameter discriminating the tested oil samples based on CCSWA was the degree of unsaturation. Overall, the employed statistical method was effective in analyzing the data obtained via the applied techniques, revealing the influence of each assessed parameter., (Copyright © 2018 Elsevier B.V. All rights reserved.)

A lab-made magnetic-mechanical robotic (MMR) system coupled to a flow-batch analyzer (FBA) for magnetic nanoparticles solid phase extraction (MSPE) is presented. As an illustrative application, an NMR-FBA couple was connected to a graphite furnace atomic absorption spectrometer (GFAAS) for quantification of trace cadmium in edible oils. Factors affecting MSPE, such as the amount of adsorbent, the type, concentration and volume of the eluent and elution time were studied. Under the optimized experimental conditions, the interferents studied did not reveal a significant change in the analytical response, indicating that proposed method is selective. The sampling rate, characteristic mass, working linear range, limits of detection (LOD), and sensitivity were 10h -1 , 0.18pg, 0.05-1.0μgkg -1 , 0.006μgL -1 , and 0.4197, respectively. An enrichment factor of 9 was achieved using a 2.5mL oil sample. In order to evaluate the accuracy, a certified reference material was analyzed by the proposed and a reference method. The values obtained were compared with the one provided from the manufacturer and no statistically significant differences were observed among three values at a confidence level of 95% using paired t-test. In addition, the precision intra-day and inter day of the proposed method and the robustness were assessed and again no statistically significant differences were observed at a confidence level of 95%. The use of a microcolumn to immobilize the MNPs is not needed with the proposed MMR-FBA-GFAAS system, thus avoiding the well-known problem of non-uniform packing of the MNPs presented in previous flow-based automatic methods. Despite a high organic load of edible oils, the method developed is simple, robust and presents satisfactory analytical features when compared with others that have been reported in the literature, suggesting that it is a potentially useful alternative to determine trace analytes in viscous matrices without external pretreatment., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The goal of this work was to evaluate the efficiency of several sorbents on removal fats from edible oils (olive, soya and sunflower) during the clean-up step for posterior determination of 165 pesticides by UHPLC-QqQ-MS/MS system. The extraction procedure employed in this work was the citrate version of QuEChERS method followed by a step of freezing out with dry ice and clean-up evaluation using i) PSA with magnesium sulfate (d-SPE); ii) magnesium sulfate and Z-sep sorbent (d-SPE); iii) Z-sep (column SPE) and iv) Agilent Bond Elut QuEChERS Enhanced Matrix Removal-Lipid (EMR-Lipid). After evaluation of the recovery results at 10, 20 and 50μgkg(-1), the EMR-Lipid showed important advantages comparing to the other sorbents evaluated, such as better recovery rates and RSD%. The method was validated at the three concentrations described above. Analytical curves linearity was evaluated by spiking blank oil samples at 10, 20, 50, 100 and 500μgkg(-1). The method demonstrated good recoveries values between the acceptable range of 70-120% and RSD%<20 for most of evaluated pesticides. In order to evaluate the performance of the method, this same procedure was employed to other oils such as soya and sunflower with very good results., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Worldwide production of phthalates has led to their undesirable presence in the food chain. Particularly edible oils have become an area of growing concern owing to numerous reported occurrences of phthalates. The analytical methods used in this field face difficulties associated mainly with matrix complexity or phthalate contamination which this study has aimed to describe and resolve. The proposed procedure consisting of liquid-liquid extraction, solid phase extraction and high performance liquid chromatography coupled with tandem mass spectrometry allowed us to analyze simultaneously 6 individual phthalates and 2 phthalate isomeric mixtures. DSC-18 SPE phase was selected for cleanup owing to the most efficient co-extract removal (assessed using high resolution mass spectrometry). Several sources of phthalate contamination were identified, however, the mobile phase was the most serious. The key improvement was achieved by equipping a contamination trap, a 50-mm reverse phase HPLC column, generating a delay between target and mobile phase peaks of the same compounds. RSDs ranging between 2.4 and 16 % confirm good precision and LOQs between 5.5 and 110μgkg(-1) reflect satisfactory blank management. With up to 19 occurrences in 25 analyzed edible oil samples and levels up to 33mgkg(-1), bis(2-ethylhexyl), diisononyl and diisodecyl phthalates were the most important contaminants., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Deep eutectic liquid organic salt was used as the solvent and a liquid phase microextraction (DES-LPME) combined with electrothermal atomic absorption spectrometry (ETAAS) was developed for separation, preconcentration and determination of lead and cadmium in edible oils. A 4:1 mixture of deep eutectic solvent and 2% nitric acid (200 µL) was added to an oil sample. The mixture was vortexed and transferred into a water bath at 50 °C and stirred for 5 minutes. After the extraction was completed, the phases were separated by centrifugation, and the enriched analytes in the deep eutectic solvent phase were determined by ETAAS. Under optimized extraction conditions and for an oil sample of 28 g, enhancement factors of 198 and 195 and limits of detection (defined as 3 Sb/m) of 8 and 0. 2 ng kg(-1) were achieved for lead and cadmium respectively. The method was successfully applied to the determination of lead and cadmium in various edible oils., (Copyright © 2015. Published by Elsevier B.V.)

In this investigation, off-line comprehensive two-dimensional liquid chromatography-atmospheric pressure chemical ionization mass spectrometry using a single column has been applied for the identification and quantification of triacylglycerols in edible oils. A novel mixed-mode phenyl-hexyl chromatographic column was employed in this off-line two-dimensional separation system. The phenyl-hexyl column combined the features of traditional C18 and silver-ion columns, which could provide hydrophobic interactions with triacylglycerols under acetonitrile conditions and can offer π-π interactions with triacylglycerols under methanol conditions. When compared with traditional off-line comprehensive two-dimensional liquid chromatography employing two different chromatographic columns (C18 and silver-ion column) and using elution solvents comprised of two phases (reversed-phase/normal-phase) for triacylglycerols separation, the novel off-line comprehensive two-dimensional liquid chromatography using a single column can be achieved by simply altering the mobile phase between acetonitrile and methanol, which exhibited a much higher selectivity for the separation of triacylglycerols with great efficiency and rapid speed. In addition, an approach based on the use of response factor with atmospheric pressure chemical ionization mass spectrometry has been developed for triacylglycerols quantification. Due to the differences between saturated and unsaturated acyl chains, the use of response factors significantly improves the quantitation of triacylglycerols. This two-dimensional liquid chromatography-mass spectrometry system was successfully applied for the profiling of triacylglycerols in soybean oils, peanut oils and lord oils. A total of 68 triacylglycerols including 40 triacylglycerols in soybean oils, 50 triacylglycerols in peanut oils and 44 triacylglycerols in lord oils have been identified and quantified. The liquid chromatography-mass spectrometry data were analyzed using principal component analysis. The results of the principal component analysis enabled a clear identification of different plant oils. By using this two-dimensional liquid chromatography-mass spectrometry system coupled with principal component analysis, adulterated soybean oils with 5% added lord oil and peanut oils with 5% added soybean oil can be clearly identified., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Stearic acid and its derivatives have been used as gelators in food and pharmaceutical gel formulations. However, the mechanism pertaining to the stearic acid based gelation has not been deciphered yet. Keeping that in mind, we investigated the role of stearic acid on physic-chemical properties of oleogel. For this purpose, two different oil (sesame oil and soy bean oil) formulations/oleogels were prepared. In depth analysis of gel kinetics, gel microstructure, molecular interactions, thermal and mechanical behaviors of the oleogels were done. The properties of the oleogels were dependent on the type of the vegetable oil used and the concentration of the stearic acid. Avrami analysis of DSC thermograms indicated that heterogeneous nucleation was coupled with the one-dimensional growth of gelator fibers as the key phenomenon in the formation of oleogels. Viscoelastic and pseudoplastic nature of the oleogels was analyzed in-depth by fitting the stress relaxation data in modified Peleg's model and rheological studies, respectively. Textural studies have revealed that the coexistence of hydrogen bond dissipation and formation of new bonds is possible under stress conditions in the physical oleogels., (Copyright © 2014 Elsevier B.V. All rights reserved.)

A method to discriminate virgin olive oil from other edible vegetable oils such as, sunflower, pomace olive, rapeseed, canola, corn and soybean, applying chemometric techniques to the liquid chromatographic representative fingerprint of sterols fraction, is proposed. After a pre-treatment of the LC chromatogram data - including baseline correction, smoothing signal and mean centering - different unsupervised and supervised pattern recognition procedures, such as principal component analysis (PCA), hierarchical cluster analysis (HCA), and partial least squares-discriminant analysis (PLSDA), have been applied. From the information obtained from PCA and HCA, two groups can be clearly distinguished (virgin olive and the rest of vegetable oils tested) which have been used to discriminate between two defined classes by means of a PLSDA model. Five latent variables (LVs) explained 76.88% of X-block variance and 95.47% of the defined classes block (γ-block) variance. A root mean square error for calibration and cross validation of 0.10 and 0.22 respectively, confirmed these results and a root mean square error for prediction of 0.15 evidences that the classification model proposed presents an adequate prediction capability. The contingency table also shows the good performance of the model, proving the capability of the LC-R-FpM, to discriminate virgin olive from other vegetable edible oils., (Copyright © 2015 Elsevier B.V. All rights reserved.)

The lipophilicity of untreated edible oils narrows the application of most published methods for the determination of antioxidant activity to hydrophilic extracts of oils. This research addresses the issue of the estimation of the total antioxidant properties of untreated edible oils by modifying two widely applied analytical methods, the Fe-Phenanthroline and the CUPRAC assays, to be used in untreated oils. The modifications pertain to the selection of mixture of solvents (ethanol-butanol in 3:1 v/v ratio), and the optimization of the reaction conditions (reagents concentration and reaction time). The developed methods were applied to a number of hydrophilic and lipophilic standard compounds and different types of commercial edible oils, as well as their corresponding aqueous or organic extracts. This implementation elucidated the differences in the antioxidant content of edible oils. All the results were compared to those of the DPPH and Folin-Ciocalteu methods and the analytical figures of merit for the methods have been estimated. Lastly, it was concluded that the modified CUPRAC assay has higher sensitivity compared to the Fe-Phenanthroline assay., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The retention characteristics of the major lipid components in biodiesels and edible oils as well as representative polycyclic aromatic compounds (PAHs) have been investigated on five different normal phase HPLC stationary phases, in order to optimize class separation for an automatized online HPLC cleanup of PAHs prior GC-MS analysis. By stepwise comparison of different hexane/MTBE compositions as mobile phases on cyano-, phenyl-, pentabromobenzyl-, nitrophenyl- and amino-modified silica columns, the capacity and selectivity factors for each analyte and column could be calculated. It was concluded that the most suitable column for backflush isolation of PAHs in biodiesel and edible oil matrices was the pentabromobenzyl-modified silica (PBB). A previously described online HPLC-GC-MS system using the PBB column was then evaluated by qualitative and quantitative analysis of a biodiesel exhaust particulate extract and a vegetable oil reference material. The GC-MS full scan analysis of the biodiesel particulate extract showed that the lipids had been removed from the sample and a fraction containing PAHs and oxygenated derivatives thereof had been isolated. Quantified mass fractions of PAHs of the reference material BCR-458 agreed well for most of the certified PAH mass fractions in the spiked coconut oil reference material., (Copyright © 2014 Elsevier B.V. All rights reserved.)

The dispersive liquid-liquid microextraction of edible oils with a low volume of an acidic solution in the presence of isopropyl alcohol allows cadmium and lead to be completely separated into the aqueous phase. After centrifugation, the metals are determined by electrothermal atomization atomic absorption spectrometry using a palladium salt for chemical modification in the heating cycle. Using a 10 g oil sample, the enrichment factor is 140, which permits detection limits of 0.6 and 10 ng kg(-1) for cadmium and lead, respectively. The results agree with those obtained after sample mineralization. Data for the cadmium and lead levels for 15 samples of different characteristics are given., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Oxidation has important effects on the quality of edible oils. In particular, the generation of aldehydes produced by the oxidation of oils is one of the deteriorative factors to their quality. The aim of this study was to develop a method to determine the aldehydes as lipid oxidation markers in edible oils. Seven aldehydes generated from lipid oxidation were studied using headspace solid-phase microextraction coupled to gas chromatography with a flame ionization detector. The extraction efficiency of five commercial fibers was investigated and the influence of extraction temperature, extraction time, desorption temperature, and desorption time were optimized. The best result was obtained with 85 μm carboxen/polydimethylsiloxane, extraction at 50 °C for 15 min and desorption in the gas chromatography injector at 250 °C for 2 min. Under the optimized conditions, the content of hexanal was the highest of the seven aldehydes in all edible oils. The limits of detection for hexanal in the three oils were found to range from 4.6 to 10.2 ng L(-1). The reproducibility of the method was evaluated and the relative standard deviations were less than 8.9%. This developed approach was successfully applied to analyze hexanal in peanut oil, soy oil, and olive oil samples, and these results were compared with those obtained using the thiobarbituric acid-reactive substances (TBARs) method., (© 2013 The Authors. Published by Elsevier B.V. All rights reserved.)

For the first time, the separation of 19 polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants in environmental and food samples by the United States Environmental Protection Agency (US-EPA) and the European Food Safety Authority was developed in cyclodextrin (CD)-modified capillary zone electrophoresis with laser-induced fluorescence detection (excitation wavelength: 325 nm). The use of a dual CD system, involving a mixture of one neutral CD and one anionic CD, enabled to reach unique selectivity. As solutes were separated based on their differential partitioning between the two CDs, the CD relative concentrations were investigated to optimize selectivity. Separation of 19 PAHs with enhanced resolutions as compared with previous studies on the 16 US-EPA PAHs and efficiencies superior to 1.5 × 10(5) were achieved in 15 min using 10mM sulfobutyl ether-β-CD and 20mM methyl-β-CD. The use of an internal standard (umbelliferone) with appropriate electrolyte and sample compositions, rinse sequences and sample vial material resulted in a significant improvement in method repeatability. Typical RSD variations for 6 successive experiments were between 0.8% and 1.7% for peak migration times and between 1.2% and 4.9% for normalized corrected peak areas. LOQs in the low µg/L range were obtained. For the first time in capillary electrophoresis, applications to real vegetable oil extracts were successfully carried out using the separation method developed here., (© 2013 Published by Elsevier B.V.)

This study aimed to establish a novel robust method for the simultaneous determination of total fatty acid esters of 4 chloropropanols including fatty acid esters of 3-monochloropropane-1,2-diol (3-MCPD esters), 2-monochloropropane-1,3-diol (2-MCPD esters), 1,3-dichloropropan-2-ol (1,3-DCP esters) and 2,3-dichloropropan-1-ol (2,3-DCP esters) in edible oils. In this method, sodium methylate in methanol was used as the reagent for the ester cleavage reaction of chloropropanols esters. The reaction products were extracted by a sodium sulfate solution, and then purified by solid-supported liquid-liquid extraction (SLE) using diatomaceous earth (Hydromatrix™) as the sorbent. Finally, the extracts were derivatized with heptafluorobutyrylim idazole (HFBI) and analyzed by gas chromatography-mass spectrometry (GC-MS). Quantification was achieved using deuterated chloropropanols as their respective internal standards, including 3-MCPD-d5, 2-MCPD-d5, 1,3-DCP-d5 and 2,3-DCP-d5. A good linear relationship between peak area and concentrations was obtained within the range of 0.025-2.000mgL(-1) with a correlation coefficients not less than 0.999 for all the chloropropanols esters. The limits of detection (LODs) of esters of 3-MCPD, 2-MCPD, 1,3-DCP and 2,3-DCP (calculated as corresponding chloropropanols) were 30, 30, 100 and 30μgkg(-1), respectively. The average recoveries of the 3-MCPD esters and the 4 chloropropanols spiked at 0.1, 0.5 and 2mgkg(-1) into blank oil matrix were typically in a range from 70.7% to 113.3%. The robust method validation data including calibration, LOD/LOQ, accuracy and repeatability and proficiency test results (Z-score: -0.5) of the official Food Analysis Performance Assessment Scheme (FAPAS) indicated that the present quantitative method could be successfully applied to the determination of total chloropropanols esters in various edible oils., (Crown Copyright © 2013. Published by Elsevier B.V. All rights reserved.)