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The aim of this study was to examine olive oils purchased in Poland for their compliance with label declarations and EEC criteria. Statistical analysis was used to compare the olive oils in terms of their content and composition of essential constituents and color parameters. Fifty olive oils (extra virgin, bioextra virgin, cold-pressed, refined, and pomace) from different countries (Spain, Italy, Greece, Portugal, Germany, France, Israel, and the European Union), were purchased commercially in Poland. The contents of triacylglycerols, sterols, and tocopherols, the fatty acid composition, and the color parameters were determined using chromatographic and spectrophotometric methods. Statistical methods were used to divide the olive oils into clusters. Our results show that the composition and color parameters of olive oils available commercially in Poland, excluding pomace olive oils, are similar. It can thus be concluded that, irrespective of the type of olive oil stated on the label, their quality is the same or very similar.

In this study, important physicochemical properties, fatty acid and sterol compositions of olive oils from the olives which harvested from Mersin (Buyuk Topak Ulak, Gemlik, Sari Ulak), Adana (Gemlik), Osmaniye (Gemlik) and Hatay (Gemlik, Kargaburun, Hasebi, Halhali) in the Eastern Mediterranean region of Turkey have been investigated. Ripening index and oil yield analysis of the olives and free fatty acids, peroxide value, UV absorbance (K 232 , K 270 ), fatty acid composition, sterol composition, erythrodiol+uvaol content, and total sterol analysis of the olive oil samples were carried out. The levels of free acidity in the olive oil samples ranged from 0.39% (Hatay Gemlik: HG3) to 2.23% (Mersin Gemlik: MG). Peroxide value ranged from 8.87 to 18.87 meq O 2 /kg. As K 232 values in the oils fluctuated between 1.4370 and 2.3970, K 270 values varied between 0.1270 and 0.1990. The results showed that all ΔK values were lower than the maximum legal limit of 0.01. The main fatty acid in all oil samples was oleic acid, ranging from 58.72% (Hatay Hasebi: HHs) to 74.54% (Hatay Gemlik: HG2). Palmitic acid values were within the percentage of 12.83% (Hatay Kargaburun: HK) to 18.50% (HHs). Total sterol content varied from 720.41 mg/kg (Hatay Kargaburun: HK) to 4519.17 mg/kg (Buyuk Topak Ulak: BTU). The β-sitosterol percentage of olive oils ranged from 76.12% (Adana Gemlik: AG) to 94.23% (Buyuk Topak Ulak: BTU). The results of this study indicated that variety significantly affect the quality indices, fatty acid and sterol compositions of olive oils significantly varied among varieties.

A simple screening method for discrimination between commercial extra virgin olive oils and their blends with other vegetable oils was developed. Squalene, which was contained relatively high amounts in virgin olive oil, was determined by HPLC after a simple pretreatment that was carried out by dilution of oil samples with 2-propanol. Tyrosol, which was contained at relatively high concentration in virgin olive oil among phenolic compounds, was determined by HPLC after a simple liquid-liquid extraction. When using squalene and tyrosol contents as axes, extra virgin olive oils could be discriminated from pure olive oils, blended oils (extra virgin olive oils with sunflower oil or grapeseed oil) and other vegetable oils. These results suggest that determining squalene and tyrosol in seed oil samples could be useful in distinguishing between extra virgin olive oil and blended oils as a screening method.

Mediterranean olive heritage richness is poorly characterized. Olive oils from minor cultivars of Northeast-Portugal (Lentisca, Madural, Rebolã, Redondal, Verdeal and Verdeal Transmontana) from centenarian trees were chemical and sensory characterized, aiming to identify autochthonous cultivars capable of producing differentiated olive oils. All oils, produced during two campaigns, were classified as extra virgin. Cv. Redondal showed the highest oxidative stability (OS), total phenols, vitamin E and C 18:1 /C 18:2 . Contrary, cv. Madural presented the lowest OS and C 18:1 /C 18:2 ratios, supporting the importance of fatty acids on OS, while cv. Verdeal had the lowest total phenols and vitamin E contents. Sensory notes of tomato, apple, dry fruits, fresh herbs, tomato leaves and cabbage were predominant on the oils of most cultivars, whilst some attributes were more specific, such as banana and kiwi (Madural), cherry and apricot (cvs. Lentisca and Madural). The chemical and sensory diversity enabled the statistical discrimination of all cultivars and harvesting years., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

The quality of extra virgin olive oils is affected mainly by hydrolytic and oxidative reactions. The present paper investigated the changes of major and minor components and oxidation indices of three monovarietal extra virgin olive oils after 18 months of storage at room temperature and in dark glass bottles conditions. After storage, the basic quality parameters such as free acidity, peroxide values, extinction coefficients, fatty acids composition, chlorophyll and carotenoid content, did not exceed the upper limits set by European Community Regulations for extra-virgin olive oils. Given the importance of the phenolic fraction, UHPLC-HESI-MS metodology was used. A decrease in 3,4-DHPEA-EDA (oleacin) and p-HPEA-EDA (oleochantal) was detected whereas, an increase of tyrosol and hydroxytyrosol was measured as a consequence of degradation of ligstroside and oleuropein derivatives. Based on the results it is possible to observe the high nutritional value of the studied oils even after 18 months of conservation.

Filtration of extra virgin olive oil is a process that may improve preservation of the quality during storage. In the current study, different aliquots of extra virgin olive oils were subjected to filtration with a traditional filter press or an innovative patented alternative process of clarification by insufflating inert gas such as nitrogen and argon; all treated samples and, as control unfiltered ones, were stored for one year to evaluate the effects of these technologies on the quality of oil during shelf-life. Basic quality indexes, diglycerides, phenolics and volatiles, as well as the sensory characteristics of samples, were determined at 4 month intervals during storage. According to the volatile compounds, phenolics and sensory analysis, the novel technique had a beneficial effect on the storage of extra virgin olive oils; accordingly, this process could be exploited by the olive oil industry., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The approach of this research was to describe the biochemical transformations of minor components of virgin olive oil with high impact on its sensory quality, specifically "volatile compounds" during its extraction process. For this purpose `Picual´, `Arbequina´ and `Hojiblanca´ cultivars were processed at three different harvesting times. Their volatile profiles and levels of enzymatic activity of "hydroperoxide lyase", responsible for the biosynthesis of C6 aldehydes related to "green and fruity notes", were monitored and identified in mesocarp, paste before kneading and paste after kneading based on the catalytic action of crude enzyme extracts. Both of them, volatiles and HPL, were analyzed by incubating with their corresponding substrates and reaction products formed were analyzed by Solid Phase Microextraction-Gas Chromatography and Mass Spectrometry. The results obtained in the present research can be useful in order to develop new markers biochemical whereby improved aroma quality in olive breeding programs or in the design of new protocol of VOO extraction., (Published by Elsevier Ltd.)

The aim of the study was to identify new potential chemical markers of extra virgin olive oil (EVOO) quality by using a multicomponent analysis approach. Sixty-six EVOOs were purchased from the Italian market and classified according to their price as low price EVOOs (LEVOOs) and high price EVOOs (HEVOOs) costing 3.60-5.90euro/L and 7.49-29.80euro/L respectively. Sensory and chemical parameters strictly related to olive oil quality have been investigated, like volatile substances, polar phenolic substances, antioxidant activity, fatty acid composition, and α-tocopherol. Significant differences in terms of chemical composition and sensory features have been highlighted between the two EVOOs classes investigated, proving a generally lower level of quality of LEVOOs, clearly showed also by means of principal component analysis. Among the most interesting outcomes, R ratio (free tyrosol and hydroxytyrosol over total free and bound forms), measuring the extent of secoiridoids hydrolysis, resulted to be significantly higher in LEVOOs than in HEVOOs. Other key differences were found in the volatile substances composition, in the stearic acid percentage and in p-coumaric acid content., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: Regulated deficit irrigation (RDI) is used in hedgerow olive orchards to achieve a sustainable balance between water savings, tree vigor and oil production. Its effects on the presence of compounds responsible for the taste of the oil and its nutritional value are controversial. The present 3-year study was conducted in an 'Arbequina' orchard (1667 trees ha -1 ) under a full irrigation (FI) treatment (470.1 mm year -1 of water) and two RDI treatments scaled to replace 60% and 30%, respectively, of FI. The quality parameters, antioxidant contents and volatiles of the extracted virgin olive oil (VOO) were analyzed., Results: In general, oils from the 30% RDI treatment had higher contents of pigments and phenolic compounds, a higher oleic/linoleic ratio and the highest oxidative stability, despite their lower tocopherol content. FI oils showed higher (E)-2-hexenal, 1-penten-3-one, ocimene, E-2-pentenal and pentene dimer contents than 30RDI oils, but lower contents of (E)-2-pentenol and volatile esters., Conclusion: The results of the present study suggest that a RDI strategy supplying 30% of the total irrigation needs induces an increase in natural antioxidants in VOO. Neither yield, nor the rest of the quality parameters were affected by the reduced irrigation. However, abundant autumn precipitation can over-ride these effects of 30% RDI treatment on oil quality. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

The novel atmospheric pressure chemical ionization (APCI) source has been used in combination with gas chromatography (GC) coupled to hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) for determination of volatile components of olive oil, enhancing its potential for classification of olive oil samples according to their quality using a metabolomics-based approach. The full-spectrum acquisition has allowed the detection of volatile organic compounds (VOCs) in olive oil samples, including Extra Virgin, Virgin and Lampante qualities. A dynamic headspace extraction with cartridge solvent elution was applied. The metabolomics strategy consisted of three different steps: a full mass spectral alignment of GC-MS data using MzMine 2.0, a multivariate analysis using Ez-Info and the creation of the statistical model with combinations of responses for molecular fragments. The model was finally validated using blind samples, obtaining an accuracy in oil classification of 70%, taking the official established method, "PANEL TEST", as reference., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The present study was performed on olives from two Algerian cultivars (Limli and Rougette de Metidja) with different rates of attack by the Bactrocera oleae fly (0%, not attacked; 100%, all attacked; and real attacked %) and the corresponding olive oils. The aim was to verify the attack effect on quality parameters (free fatty acid, peroxide value, K232 and K270, oxidation stability), bioactive compounds (fatty acids and tocopherols, and total phenols and flavonoids), and on the antioxidant (reducing power, FRAP, β-carotene bleaching inhibition, ABTS and DPPH) and antibacterial (against 8 referenced human enteropathogenic bacteria by the agar disc diffusion method) capacities. Oils from infested olives were downgraded to the virgin olive oil category. Rougette de Metidja, the cultivar with a higher drupe size, was more attacked than Limli. The B. oleae attack causes an important decrease in the total phenolic contents (>30%) but to a lesser degree in the case of tocopherols. Among them, α-tocopherol is the most affected. The antioxidant and antibacterial activities were highly correlated with phenolic levels. The results of this study show the importance of controlling the fly attack because it causes a decrease in the beneficial health effects of olive oils.

The geography that is now Turkey has produced olives and their oil for millennia, but major changes in the industry have been underway in the last decade, with many producers now focusing on quality over quantity. Based on fieldwork with olive oil producers, harvesters, laboratory technicians, equipment engineers, and others in the industry, this article describes this ‘‘quality turn,’’ what is driving it, who is involved in it, how it unfolds, and what its effects are. Some of the players involved in producing olive oil in Turkey for decades or longer have witnessed important generational changes, including more women entering the sector and technological innovation. Prominent roles are now played by laboratories and tasting competitions, involving the recalibration of human sense perceptions on the part of producers (and, more slowly, consumers) to be commensurate with international standards for defining target aroma profiles in olive oil. [ABSTRACT FROM AUTHOR]

Furfurals, including 2-furaldehyde, 5-methylfurfural and 5-hydroxymethylfurfural, widely exist in carbohydrate-rich daily foods, and may have toxic effects on humans. Here, a new headspace extraction-paper spray mass spectrometry (HSPS-MS/MS) method was established for furfural detection, in which the extraction and derivatization of volatiles with pre-loaded derivatization agent on paper tips is combined with paper spray mass spectrometry for detection. By this simple and cheap approach, interference of non-volatile matrix compounds is prevented, and the derivatization agent improves electrospray-type ionization efficiency, thus increasing selectivity and sensitivity. The approach was optimized, by investigating positioning during extraction, extraction duration, derivatization agent, addition of internal standard for quantification and finally validated. For this, the developed method was benchmarked against HPLC-UV and could obtain detections limits of 0.32–0.40 μg mL−1 for 2-furaldehyde, 5-methylfurfural and 5-hydroxymethylfurfural in olive oil. Moreover, fast screening of free furfurals in soy sauce, coffees and teas was demonstrated with the HSPS-MS/MS method. [Display omitted] • A simple and inexpensive paper tip was used for headspace extraction and selective furfural enrichment/derivatization. • A paper-based headspace extraction-paper spray mass spectrometry (HSPS-MS/MS) method was established for furfural analysis from olive oil. • The method achieves relevant detection limits of 0.32–0.40 μg mL−1 without any chromatography. • Fast screening of free furfurals in instant drinks was achieved for food quality and safety control. [ABSTRACT FROM AUTHOR]

The investigation of volatile compounds in the headspace of liquid samples can often be used for detailed and non-destructive characterisation of the sample. This has great potential for process control or the characterisation of food samples, such as olive oil. We investigated, for the first time, the plume of substances released from olive oil droplets by laser desorption in a feasibility study and applied ion mobility spectrometry coupled to rapid GC pre-separation to enhance selectivity. Our investigation demonstrated that significantly more substances can be detected and quantified via laser desorption than in the usual headspace, enabling a rapid (5–10 min), sensitive (low ng/g range) and comprehensive analysis of the sample, with the potential for quality control and fraud identification. Therefore, laser desorption provides a useful sampling tool for characterising liquids in many applications, requiring only a few µL of sample. [ABSTRACT FROM AUTHOR]

Oxidation level and quality characteristics of olive oil require monitoring during storage to ensure that their amounts are maintained in the lawful thresholds. It is especially important for licensing their commercialization as high-value virgin olive oils. The present research proposes a novel approach based on the fusion of dielectric spectroscopy and computer vision for the characterization of olive oil quality indices during storage in order to reduce the time of analysis, reagent consumption, manpower and high-cost equipment. Colour features in RGB, HSV and L ∗ a ∗ b ∗ spaces were extracted as well as dielectric features in the frequency range of 40 kHz to 20 MHz for each olive oil sample. After data pre-processing, classification and prediction models were developed and compared. Several machine learning techniques were investigated for storage time classification and quality indices prediction including artificial neural network (ANN), support vector machine (SVM), Bayesian network (BN) and multiple linear regression (MLR). The best result in the classification of olive oils during the storage period was obtained by BN technique with 100% accuracy. Among predictive models, the SVM with RBF kernel had the best results (R = 0.969, 0.988 and 0.976) for prediction of peroxide value (PV), UV absorbance at 232 nm (K 232 ) and chlorophyll, respectively. Also, the SVM with normalized polynomial kernel had the best results (R = 0.989, 0.976, 0.969 and 0.969) for prediction of p-Anisidine value (AV), total oxidation value (TOTOX), UV absorbance at 268 nm (K 268 ) and carotenoid, respectively. The ANN with 40-2-1 topology gave the best result (R = 0.977) for modelling free acidity (FA). Results of this research can be utilized for developing an efficient and reliable system for olive oil quality evaluation and monitoring by industry. [ABSTRACT FROM AUTHOR]

Aroma is an important quality criterion for extra virgin olive oil. The goal of this study was to determine C and C volatile compounds in different Turkish olive oils. Two factors namely (1) olive cultivar including Ayvalik, Memecik, and Topakasi, and (2) harvest time (ripening degree) were studied. Both factors significantly affected the volatile profiles of the studied oils. Headspace solid phase micro-extraction with GC/MS was used to detect volatiles in different olive oils. The detected volatile compounds included up to 11 compounds (4 from C, and 7 from C). Hexanal and ( E)-2-hexanal were predominated as the major volatiles in Ayvalik, and Memecik oils, while pentanal, and hexanal were predominated in Topakasi oil. Topakasi oil was also characterized by its low content of ( E)-2-hexenal. The only clear trend observed during ripening of olives was the increase in the total content of esters. Therefore, the information obtained in this study is useful in selecting the proper harvest time for each cultivar according to the desired volatile compounds found in the oil. [ABSTRACT FROM AUTHOR]

Changes occurring in refined olive pomace oil (ROPO) blended with refined palm oil (RPO) during repeated frying cycles were monitored. Four ratios of ROPO/RPO blends were prepared: (100:0), (75:25), (50:50) and (25:75). The effect of deep-frying was studied by assessing the changes in iodine value, acid value, color value and fatty acids composition. The results show that the mixture ROPO/RPO (25:75) is the most stable compared with other blends. The fate of 3-MCPD and glycidyl esters during deep-frying was investigated showing no endogenous formation of the esters during 16 h of deep-frying. [ABSTRACT FROM AUTHOR]

Extra-virgin olive oils used in the production of flavoured oils can derive from a single cultivar or can be a blend of two or more mono-varietal oils. In order to investigate the effects of the characteristics of the oil blends on the quality of the deriving flavoured oils, three mono-cultivar extra-virgin olive oils (Coratina, Peranzana, Ogliarola) were used to produce three blends, which were successively flavoured by infusion. From each blend, three types of flavoured olive oils were produced: basil, chilli pepper, and garlic + chilli pepper. Mono-varietal extra-virgin olive oils, blends, and flavoured oils were submitted for routine analyses and for determination of polar compounds, phenolic profile, antioxidant activity, and volatile profiles. The panel and consumer tests were also carried out on the flavoured oils. Along with the undoubted influence of the flavouring agents, the quality parameters of each blend changed and their changes greatly depend on the starting blend. The parameters mostly affected by oil blend were: acidity, K, peroxide values, diacylglycerols, polar compounds, total phenolics, antioxidant activity, and phenolics such as p-coumaric acid, tyrosol acetate, vanillic acid, tyrosol, hydroxytyrosol, hydroxytyrosol acetate, dialdehydic form of elenolic acid linked to tyrosol, and ligstroside aglycone, oleuropein aglycone. The effects of oil blending were rather limited on volatile profiles and sensory characteristics. [ABSTRACT FROM AUTHOR]

Continuous application of high power ultrasound (HPU) on olive paste previous to malaxation at laboratory scale for virgin olive oil (VOO) extraction and its effect on process yield and the VOO quality have been studied. For the VOO samples, we determined the quality indices (free acidity value, peroxide value, K232, K270), bitterness, volatile composition, phenolic content (total and biophenols), tocopherol content, and pigments. The application of ultrasound induced a quick heating of the paste from 20 to 28°C. The sonication treatment improved the industrial oil yield by 1% and the oil extractability by 5.74%. Moreover the HPU treatment did not cause changes in the quality indices, fatty acid composition and volatile aromatic compounds of the VOO. Furthermore the fat autoxidation process was not accelerated by this treatment. Meanwhile oil obtained from olive pastes treated with HPU showed higher content of tocopherol, chlorophylls and carotenoids whereas a reduction in phenolic content and bitterness index was observed. Practical applications: The high power ultrasound (HPU) treatment of olive paste, before malaxation during the virgin olive oil (VOO) elaboration process, can improve the oil extraction yield without alteration of its quality parameters. The olive paste instantaneous heating observed with the HPU can allow the reduction of the malaxation step duration. The results obtained nowadays at laboratory scale are promising for the possibility of the continuous HPU treatment introduction in the olive oil elaboration process as aid or alternative to the malaxation. For this purpose further experiment at pilot and industrial scale are needed. Continuous application of high power ultrasound before malaxation and its effect on the oil extractability and virgin olive oil characteristics. [ABSTRACT FROM AUTHOR]

The new health claim on 'olive oil polyphenols' recently approved by the European Commission has produced a dramatic increase in the interest in these antioxidant compounds. Although this interest has been focused mostly on extra virgin olive oils (EVOOs), virgin olive oils (VOOs) qualified as having non-oxidative sensory defects, mostly caused by fermentation and the action of fungi on olives, may still have a considerable amount of phenols, even though their sensory quality is not flawless. This study is focused on the phenol composition of all the VOO categories: EVOOs with their ample variability in phenolic composition, VOOs with slight defects, lampante virgin olive oils (LVOO), and reference materials of defective VOOs. The average content of phenols in the analyzed EVOOs (410 ± 16 mg/kg) is higher than the recommended consumption by the health claim (250 mg/kg). VOOs qualified with non-oxidative defects contain high concentrations of phenols (234 ± 27 mg/kg), but only samples characterized by the wet-wood sensory defect show concentrations of phenols close to 250 mg/kg. Practical application: This study has demonstrated that VOOs with slight sensory defects still have a high concentration of phenols, providing antioxidant properties regarding health benefits and stability. The health claim should be not only applied to the extra virgin olive oil category, but also to some virgin olive oils with sensory defects. Profiles of phenols according to their main sensory defect. Picual (A), Hojiblanca (B), rancid (C), winey-vinegary (D), fusty (E), and musty (F). [ABSTRACT FROM AUTHOR]

In this research, the evaluation of the pre-heating effect on olive paste before malaxation was performed. The olive paste was treated by means of a tubular heat exchanger. The heat exchanger performances on yield and olive oil quality were evaluated considering two different types of olive paste obtained, respectively, by means of a disc crusher and a de-pitter machine. The experimental tests were conducted on an industrial olive oil extraction plant. The results of the experimental test showed that it is possible to reduce the malaxation time by about 10 min, maintaining constant the extraction yield, when a disc crusher was used. On the other hand, using the heat exchanger to condition the de-stoned paste, a reduction of the malaxation time compared to the control test was observed, but with significant loss in extraction yield. Concerning the olive oil quality, the flash thermal treatment of the olive paste after the crushing operation improves the phenolic and volatile compound content significantly with respect to the traditional process, in which the malaxation time has a duration of at least 30 min. By employing a tubular heat exchanger we observed some advantages, like the reduction of malaxation time and the improving of phenolic and volatile compounds. Practical applications: The practical application of this research concerns the possibility of evaluating the effects inherent in the insertion of a tubular heat exchanger before the malaxer, in an industrial olive oil extraction plant. The effects were evaluated on an industrial scale olive oil extraction plant considering these quantitative parameters: extraction efficiency of the decanter and the amount of oil lost in the husk. The olive oil quality was also evaluated. The research provides useful information to the operators of the olive oil sector and to researchers in understanding the changes manifested in the extraction plant in traditional configuration and innovative configuration with the tubular heat exchanger. A tubular heat exchanger to pre-heat the olive paste in an industrial olive oil extraction plant. [ABSTRACT FROM AUTHOR]

The aim of this study was to provide an additional element of knowledge and evaluation on extra virgin olive oil from the Italian region Calabria, belonging to the Grossa di Gerace cv. Then, the following chemical, physical-chemical, and sensory analyses have been performed: free acidity, peroxide value, UV spectrophotometric indices, ethyl esters, waxes, tocopherols, fatty acids, triglycerides, sterols, alcohols, phenolic substances, dynamic headspace volatile compounds, and sensory profile. The analytical investigation allowed us to highlight the great potential of this cultivar: a 'quality' product that will satisfy consumer expectations for a particular food, and especially a 'typicality' because of its unique attributes in the zone of production. According to the results provided by the analysis carried out on the extra virgin olive oil samples from 'Grossa di Gerace' and its mixtures with another important cultivar of Calabria, 'Carolea,' and thanks to statistical tools, 17 variables have been identified that could be considered markers of single cultivar olive oils of 'Grossa di Gerace': phytol, palmitic acid, 1-hexanol, trans-2-hexen-1-ol, α-amyrin, 3,4-DHPEA-EA-H, palmitoleic acid, apigenin, methyl-luteolin, geranylgeraniol, 3,4-DHPEA-EA, OOL + LnPP, PoOO, PoOP + SPoL + SOLn + SPoPo, citrostadienol, luteolin, and trans-2-hexenal. The Principal Components Analysis (PCA) applied to the 17 variables has permitted us to distinguish blends with more than 10% of 'Carolea.' Practical applications: The study carried out on single cultivar extra virgin olive oil of Grossa di Gerace has been executed for several practical applications: (i) the knowledge of the chemical profile of the oil is useful to define the sensory, nutritional, and conservative quality of this product; (ii) the identification of analytical parameters is useful for a Protected Denomination of Origin (PDO) characterization; (iii) to protect the single cultivar extra virgin olive oil, inserted into the ATP, from mixtures with other oils, by the identified analytical markers. According to the results provided by the analysis carried out on the extra virgin olive oil samples from 'Grossa di Gerace' and its mixtures with another important cultivar of Calabria, 'Carolea,' and thanks to statistical tools, 17 variables have been identified that could be considered markers of single cultivar olive oils of 'Grossa di Gerace.' The Principal Components Analysis applied to the 17 variables has permitted us to distinguish blends with more than 10% of 'Carolea.' [ABSTRACT FROM AUTHOR]

The characterisation of different olive oil categories (extra virgin, virgin and lampante) using Ion Mobility Spectrometry (IMS) was improved by replacing the multicapillary column (MCC) with a capillary column (CC). The data obtained with MCC–IMS and CC–IMS were evaluated, studying both the global and the specific information obtained after the analysis of the volatile fraction of olive oils. A better differentiation of the oil categories was obtained employing CC vs MCC, since the classification percentage obtained with the CC–IMS was 92% as opposed to 87% obtained with MCC–IMS; although in productivity analytical terms, MCC offer a faster analysis than GC. The specific information obtained was also used to build a database, with a view to facilitating the characterization of specific attributes of olive oils. A total of 26 volatile metabolites (aldehydes, ketones, alcohols and esters) were identified. Finally, as revealed by an ANOVA test, some volatiles differed markedly in content among the different categories of oil. The data obtained confirms the potential of IMS as a reliable analytical screening technique, which can be used to assign the correct category to an olive oil sample. [ABSTRACT FROM AUTHOR]

The fluorescence spectra of some olive oils were examined in their natural and oxidised state, with wavelength range emissions of 300–800 nm and 300–400 nm used as excitation radiation. The fluorescence emissions were measured and an assessment was made of the relationship between them and the main quality parameters of olive oils, such as peroxide value, K232, K270 and acidity. These quality parameters (peroxide value, K232, K270 and acidity) are determined by laboratory methods, which though not too sophisticated, they are required solvents and materials as well as time consuming and sample preparation; there is a need for rapid analytical techniques and a low-cost technology for olive oil quality control. The oxidised oils studied had a strong fluorescence band at 430–450 nm. Extra virgin olive oil gave a different but interesting fluorescence spectrum, composed of three bands: one low intensity doublet at 440 and 455 nm; one strong band at 525 nm; and one of medium intensity at 681 nm. The band at 681 nm was identified as the chlorophyll band. The band at 525 nm was derived, at least partially, from vitamin E. The results presented demonstrate the ability of the fluorescence technique, combined with multivariate analysis, to characterise olive oils on the basis of all the quality parameters studied. Prediction models were obtained using various methods, such as partial least squares (PLS), N-way PLS (N-PLS) and external validation, in order to obtain an overall evaluation of oil quality. The best results were obtained for predicting K270 with a root mean square (RMS) prediction error of 0.08 and a correlation coefficient obtained with the external validation of 0.924. Fluorescence spectroscopy facilitates the detection of virgin olive oils obtained from defective or poorly maintained fruits (high acidity), fruits that are highly degraded in the early stages (with a high peroxide value) and oils in advanced stages of oxidation, with secondary oxidation compounds (high K232 and K270). The results indicate the potential of a spectrofluorimetric method combined with multivariate analysis to differentiate, and even quantify, the levels of oil quality. The proposed methodology could be used to accelerate analysis, is inexpensive and allows a comprehensive assessment to be made of olive oil quality. [ABSTRACT FROM AUTHOR]

Five virgin olive oil samples were evaluated by 122 consumers for their color acceptability and expected quality on 9-point structured scales. A description of the attributes expected in the different oils was obtained from the responding consumers by means of a check-all-that-apply questionnaire consisting of a list of 17 possible virgin olive oil attributes. Hierarchical cluster analysis led to the identification of two consumer clusters with distinct behavior. Whereas one consumer cluster attributed higher quality to those oils that were greener in color, which they described as tasty, rich-flavored, strong-tasting, herb-flavored and expensive, consumers in the other cluster assumed that greener olive oils were of a poorer quality, as they described them as strange-tasting, strong-tasting, herb-tasting and defective. Despite the contrasting perception of a virgin olive oil's green color, the respondents, irrespective of cluster, presumed that the virgin olive oil that was the yellowest in color was of poor quality and cheap, also assuming that it had a milder taste than the other oils. [ABSTRACT FROM AUTHOR]

Abstract: The potential of visible fingerprints and physical–chemical parameters in combination with multivariate data analysis was examined to classify extra virgin olive oils (EVOOs) from different Spanish regions according to their geographical origin. Firstly, spectral and quality parameters matrices were processed separately and subsequently were joined to evaluate the effect of synergy on the information obtained from the different methodologies. Linear discriminant analysis (LDA) and partial least squares discriminant analysis (PLS-DA) were performed as classification methods. The results revealed a perfect discrimination between the defined categories after performing PLS-DA on the Fused matrix, reaching 100% of correct classifications and showed a clear improvement in the overall prediction rates (92.5%), so that the effect of synergy was confirmed. These accurate results emphasise the feasibility of the proposed strategy and encourage the development of similar approaches based on visible spectroscopy in olive oil quality and traceability determination. [Copyright &y& Elsevier]

ABSTRACT The effects of both the irrigation regimes (50% evapotranspiration [ETc], 75% ETc and 100% ETc) and the growing area on the quality of Chétoui virgin olive oil obtained from an intensively managed orchard in a semi-arid and arid area with a Mediterranean climate in Tunisia were evaluated. The quality, determined using the usual parameters for virgin olive oils (acidity and peroxide value), was slightly affected by irrigation in the north, and more significatively in the south. Irrigation positively affected fruit weight (86.1% of variability) in all cases. Growing area exhibited a more important effect on the fatty acid profile (96.3% of variability) than the irrigation management (1.8% of variability). Total phenols and bitterness intensity strongly differed: the different irrigation regimes applied in the north had no effect on the bitterness of Chétoui virgin olive oils, whereas the same water management applied in the south caused a marked decrease in both bitterness category and total phenols. Aroma compounds exhibited different behavior according to growing area and irrigation management. PRACTICAL APPLICATIONS This research is strongly oriented to the agronomic application. The obtained results can orient an agronomist to the suitable irrigation management, applied on the appropriate growing area, in order to obtain a good yield and a balanced composition of the olive oil using the least amount of water. [ABSTRACT FROM AUTHOR]

The study for the elaboration and certification of four olive oil reference materials covering all the physical–chemical characteristics, defined in Commission Regulation (EC) 1989/2003, is reported herein. The different steps of the process, preparation of reference materials, homogeneity and stability studies, and characterization study have been carried out for 14 laboratories from five European countries. The certificate of analysis for these certified reference materials (CRMs) provide assigned values for concentrations of more than 50 parameters or characteristics of olive oils in compliance with the European legislation about the labeling of food products. The certified values and its corresponding uncertainties were obtained applying robust statistics to the raw data provided by the laboratories taking part in the interlaboratory study. The certificate is valid for a maximum period of 18 months from the elaboration date. These four CRMs are intended for use as a primary material for quality control and for validation of analytical methods for measurements in authentication and adulteration problems of olive oils. [ABSTRACT FROM AUTHOR]

The article focuses on American Botanical Council-American Herbal Pharmacopoeia-National Center for Natural Products Research Botanical Adulterants Prevention Program announces the publication of a new Laboratory Guidance Document on olive oil. Topics include the oil of the olive fruit is one of the most popular culinary oils, the oil is also widely used in topical formulations such as lotions, and lip balms, and the oil is used as a carrier oil for fat-soluble vitamins and herbal extracts.

The usefulness of headspace (HS)-gas chromatography (GC)-ion mobility spectrometry (IMS) has been explored for quantitative purposes, focusing on ethanol in olive oils. For that, since this emerging analytical tool provides a 2D analysis, different calibration curves were built using the height, area and volume of the detected species, i.e. a protonated monomer and a proton-bound dimer of ethanol. The methodology was validated and the quantification results compared to those obtained by GC coupled to more conventional detectors. Once then, the content of ethanol was determined in 81 olive oil samples. The ethanol content was lower than 12 mg/kg for 89% of extra virgin olive oil samples, whereas it was higher than 12 mg/kg for around 90% of virgin olive oil samples. This concentration value was used as a limit to support the decision-making process for olive oil classification into extra virgin, virgin, and lampante olive oil by complementary methods, sensory analysis and chemometrics. In conclusion, the proposed HS-GC-IMS method requires no sample pretreatment, shows low limits of detection (0.095 mg/kg) and quantification (0.100 mg/kg) and is faster enough to monitor the content of this marker in olive oils in the industry. • GC-IMS for rapid quantitative analysis of ethanol in olive oils. • Ethanol is a potential classification marker of extra virgin and virgin olive oils. • Alternatively, lampante olive oils show no clear trends concerning the ethanol content. • The determination of ethanol in olive oil do not requires sample pretreatment. [ABSTRACT FROM AUTHOR]