Monovarietal Extra Virgin Olive Oils Research Articles

Usefulness of the 1H NMR Multisuppression Approach for the Global Characterization of Monovarietal Extra-Virgin Olive Oils

Extra-virgin olive oil (EVOO) is one of the most appreciated vegetable oils worldwide, but its high price makes it prone to suffer adulteration with lower quality oils. Therefore, it is important to have methodologies able to study EVOO composition as a whole in a simple and fast way, in order to guarantee its quality and safety. For this purpose, in this study, commercial samples of five Spanish olive cultivars (Arbequina, Arroniz, Cornicabra, Hojiblanca, Picual) were studied by Proton Nuclear Magnetic Resonance (1H NMR) spectroscopy, using standard and multisuppression pulses. The aim was to explore the possibility of 1H NMR use to characterize in a single run and in a global way the composition of these monocultivar oils, regarding not only their main components (fatty acids supported on triglycerides) but also minor ones (squalene, sterols, diterpenic wax esters of phytol and geranylgeraniol, phenolic and secoiridoid derivatives, like tyrosol, hydroxytyrosol, oleacein, oleocanthal, and lignans, among others, and aldehydes). The use of univariate and multivariate statistical analyses confirmed the presence of compositional features that were specific to some olive varieties. The Arbequina and Arroniz oils showed the most characteristic features that allowed for clearly differentiating them from the others. In contrast, the discrimination between the Cornicabra, Hojiblanca and Picual oils was not so easily achieved.

HS-SPME-GC-MS and Chemometrics for the Quality Control and Clustering of Monovarietal Extra Virgin Olive Oil: A 3-Year Study on Terpenes and Pentene Dimers of Italian Cultivars.

Terpenes and pentene dimers are less studied volatile organic compounds (VOCs) but are associated with specific features of extra virgin olive oils (EVOOs). This study aimed to analyze mono- and sesquiterpenes and pentene dimers of Italian monovarietal EVOOs over 3 years (14 cultivars, 225 samples). A head space-solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) method recently validated was used for terpene and pentene dimer quantitation. The quantitative data collected were used for both the characterization and clustering of the cultivars. Sesquiterpenes were the molecules that most characterized the different cultivars, ranging from 3.908 to 38.215 mg/kg; different groups of cultivars were characterized by different groups of sesquiterpenes. Pentene dimers (1.336 and 3.860 mg/kg) and monoterpenes (0.430 and 1.794 mg/kg) showed much lower contents and variability among cultivars. The application of Kruskal-Wallis test-PCA-LDA-HCA to the experimental data allowed defining 4 clusters of cultivars and building a predictive model to classify the samples (94.3% correct classification). The model was further tested on 33 EVOOs, correctly classifying 91% of them.

Stability of monovarietal Sicilian olive oils under different storage condition: Chemical composition, sensory characteristics, and consumer preference

Monovarietal olive oils, known for their distinct aromatic profiles, face challenges in preserving their initial quality due to variations in stability and susceptibility to oxidative deterioration. This study focused on the storage stability of two Italian cultivars, ‘Biancolilla’ and ‘Cerasuola’, from Sicily, chosen for their aromatic complexity and divergent storage stability. Oils, whether filtered or unfiltered, underwent storage at two thermal regimes (18 °C and – 20 °C) over a year. The combination of filtration and low-temperature storage was employed to mitigate oxidative deterioration and hydrolytic processes, as filtration removes suspended particles and emulsified water, while low temperatures slow down enzymatic activities and oxidative reactions, thereby enhancing the overall stability and shelf life of the olive oils. Unfiltered samples at room temperature showed a significant increase in secoiridoid aglycone derivatives (Hydroxytyrosol and Tyrosol) due to hydrolytic processes, along with a decrease in secoiridoid aglycone. Filtration delayed these processes, with a more pronounced effect observed when combined with −20 °C storage. Sensory analysis identified the emergence of the “fusty” defect in the less resilient ‘Biancolilla’ cultivar after six months, a phenomenon mitigated by filtration and freezing. Consumer tests validated these findings. In summary, the synergistic approach of combining filtration with low-temperature storage emerges as a promising strategy for maintaining high-quality standards, especially for less stable monovarietal extra virgin olive oils. This strategy ensures compliance with EU regulations beyond the conventional 12-month shelf life, offering a practical solution for preserving the nutritional and sensory quality of olive oil.

Chemical Composition of Monovarietal Extra Virgin Olive Oils Obtained from Tunisian Mills: Influence of Geographical Origin

Chemical Composition of Monovarietal Extra Virgin Olive Oils Obtained from Tunisian Mills: Influence of Geographical Origin

Classification of Algerian olive oils: Physicochemical properties, polyphenols and fatty acid composition combined with machine learning models

The regulation of olive cultivar and geographical origin is a requirement for the global extra virgin olive oil market, due to its significant impact on consumer choice. Our work involves obtaining a promising marker parameter for cultivar and geographical origin that can be used to verify declared labels. The effects of these factors on the physicochemical parameters and composition of monovarietal extra virgin olive oil (MEVOO) from Algeria were studied. Thirteen olive fruit varieties were analyzed using different physicochemical methods, including phenolic and fatty acid composition. Five classification techniques, random forests (RForest), gradient boosted trees (GBoost), Naïve Bayes (NBayes), logistic regression (LRegression) and decision tree (DTree), were applied and their results were compared. The best validation accuracy of 91.7 % was achieved with DT classification through a feature selection procedure using a genetic algorithm (GA). These results demonstrate the effective use of machine learning techniques to rapidly classify different Algerian varieties based on their compositional fingerprints.

Storage Effects on Bioactive Phenols in Calabrian Monovarietal Extra Virgin Olive Oils Based on the EFSA Health Claim.

The beneficial properties of extra virgin olive oil (EVOO) on lipids blood levels were recognized by the European Food Safety Authority (EFSA) with a health claim, specifically referring to EVOOs containing at least 5 mg of hydroxytyrosol and its secoiridoids derivatives per 20 g of oil. The main purpose of the work was to characterize the phenolic profile of two commercially available Calabrian monovarietal EVOOs (Nocellara del Belice, VN; Dolce di Rossano, VDR), and to study the effect of one-year storage on secoiridoids composition, by monthly controls. A new UHPLC-ESI-HRMS method was developed and validated, thus facilitating the EFSA claim application and allowing producers to valorize their products. Seven biologically active compounds were chosen: tyrosol, hydroxytyrosol, oleocanthal, oleacein, oleuropein aglycone, verbascoside, and oleuropein. LODs and LOQs were 0.001-0.02 mg g-1 and 0.002-0.08 mg g-1, respectively. The variation coefficients were ≤20% and the percentage of recovery was between 89-109%. During the 12-month storage period, the concentration of selected compounds ranged between 1258.78-1478.91 mg Kg-1 for VN, and 1408.22-2071.45 mg Kg-1 for VDR, with a decrease of 15% and 32% respectively. The method allows an accurate quantification of EVOO phenols thus being useful to certify the nutraceutical properties of olive oil.

In vitro study of potential prebiotic properties of monovarietal extra virgin olive oils

Olive oil, essential ingredient of the Mediterranean diet, is attracting a growing interest due to increasing evidence on its beneficial effects on human health. This study investigated whether extra virgin olive oil (EVOO) possess prebiotic properties. Twenty different monovarietal EVOO samples from 5 Marche region cultivars (Italy) were studied. The prebiotic activity of EVOOs was assessed monitoring the selective stimulation of gut bacterial species and the short chain fatty acids (SCFAs) production, using an in vitro fermentation system. All EVOOs selectively stimulated Lactobacillus spp., with a stronger activity than that observed in the inulin fermentation (positive control). Also, the bifidobacteria population increased; this bifidogenic stimulation was of EVOOs from Raggia cultivar. SCFAs appeared significantly higher after 24 h in all EVOO fermentations than in the control. Acetic and propionic acids production was particularly stimulated. Overall, most of the investigated EVOOs had a potential prebiotic activity, similar or stronger than inulin.

Monovarietal olive oils fortified with carotenoids: Physicochemical and sensory trends and taste sensor evaluation

AbstractThis study evaluated the effects of lutein or β‐carotene incorporation (0.1 mg/ml) on the quality, sensory attributes and stability of Arbequina, Picual or Royal monovarietal extra virgin olive oils. The fortification significantly decreased (p value < 0.05) the chemical quality of the fortified oils (peroxide values: +3% to +34%; extinction coefficients: +4% to +55%). The negative impact was higher on Arbequina oil, followed by Royal and Picual oils, especially in lutein fortified oils. Nevertheless, all fortified oils fulfilled the legal thresholds required by extra virgin category. Compared with the unfortified ones, fortified oils showed significantly lower (p value < 0.05) stability and total phenol content (−6% and −12%, respectively). The fortification changed the oils' green color into a yellowish‐orange color. Bitterness, pungency and sweetness varied significantly (p value < 0.05) with the type of monovarietal olive oil. Bitter and pungent intensities increased in Arbequina and Picual fortified oils (+29% to +191%, especially for the former) and decreased in Royal fortified oils (−42% and −62%, respectively). The fortification increased the sweetness of Picual and Royal oils (+109% and +10%), but decreased in Arbequina oils (−74%). The physicochemical‐sensory changes induced by the fortification allowed a clear differentiation of the monovarietal oils and, for each oil cultivar, by fortification agent. The use of an electronic tongue further confirmed the fortification impact at the phenolic and sensory levels, allowing the discrimination of unfortified and fortified oils and the quantification of oils' bitterness, pungency or sweetness and, in a less extent, the total phenols contents.

Clustering Monovarietal Extra Virgin Olive Oil According to Sensory Profile, Volatile Compounds, and k‐Mean Algorithm

AbstractA real valorization of monovarietal extra virgin olive oils (EVOOs) through diverse sensory profiles is missing, hindering different uses of samples with different sensory profiles and leading to negative impacts on EVOO competitions and consumer choices. The aim of this research is to group monovarietal EVOOs according to similar sensory and chemical profiles. The volatile and phenolic composition and the sensory profile of 46 monovarietal EVOOs are analyzed by head space‐solid phase micro extraction‐gas chromatography‐mass spectrometry, HPLC‐DAD, and Panel Test; the data are used to feed a k‐mean algorithm aimed at samples clustering. A group of non‐monovarietal samples is also included. It is hypothesized that samples of a cultivar are located in a cluster, while non‐monovarietal samples are randomly located in different clusters. Two clusters of samples are identified; all samples belonging to a specific cultivar are in the same cluster and the non‐monovarietal ones randomly placed in the two clusters. The significant attributes in differentiating between the two clusters belong to sensory descriptors and volatile compounds; phenolic compounds do not give significant differentiation. All sensory descriptors result in prevalence in one cluster. The two clusters are differentiated by volatile organic compounds (VOCs) originating by different branches of the lipoxygenase‐pathway.Practical Applications: The results of this research will help toward a real valorization of extra virgin olive oils (EVOOs), and particularly, the monovarietal ones. In this sense, the results clearly suggest the use of an adequate profile sheet for the definition of the sensory profile of monovarietal EVOOs. By this way, during EVOO competitions, samples with a certain type of sensory profile will compete against samples with the same type of sensory profile, just as it happens for other types of products.

Deconstructing extra virgin olive oil through fractionation processes

Arbequina monovarietal extra virgin olive oil (EVOO) was fractionated through a multi-step dry fractionation method. Three of the isolated fractions were selected and analyzed: one being liquid at 4 °C, and two being solid at 4 °C, and at 12 °C. Differential scanning calorimetry (DSC) combined with synchrotron radiation X-ray diffraction (SR-XRD) techniques were employed to monitor the polymorphic crystallization and transformation processes when samples were cooled from the melt to complete crystallization and reheated at a rate of 2 °C/min. Fatty acid profiles and α-tocopherol contents were also determined for EVOO and associated fractions. Each sample exhibited a different and unique crystallization and polymorphic behavior, and the number of crystallizing forms and complexity of transitions increased for solid fractions. In more detail, just two polymorphs (β’3-2L and β’2-2L) were detected in the liquid fraction, whereas the fraction which remained in the solid state at 12 °C exhibited six different phases (α-2L; β’3-2L; β’2-2L; β’1-2L; β’2-3L; β’1-3L). These dissimilarities were strongly correlated with meaningful variations in the fatty acid moieties forming TAG structures and caused large deviations in the crystallization and melting temperatures. As an example, melting temperatures of the liquid and the solid fraction at 12 °C were about −3 °C and 17 °C, respectively. It may be worth exploring the potential of EVOO fractions to be used for improving properties of food stuff, among others. The liquid fraction may be of interest due to its high nutritional value owing to elevated contents in monounsaturated fats and antioxidants, whereas the solid fraction at 12 °C may become a good choice to be used as a high-oleic soft fat.

Evaluation of Selected Quality Parameters of "Agristigna" Monovarietal Extra Virgin Olive Oil and Its Apple Vinegar-Based Dressing during Storage.

This study aimed to investigate the quality parameters and the oxidative stability (180 days of storage) of a water–oil emulsion formulated with Calabrian (Italy) monovarietal Agristigna extra virgin olive oil and apple vinegar. The best extra virgin olive oil/apple vinegar ratio was found to be 85/15 (v/v) and lecithin (2% w/v) was the best additive to reach proper stability and viscosity over time. An increase of lightness parameters was evidenced in both products in a storage time-dependent manner. During storage, both oil and dressing showed a free acidity level beyond the accepted limit for extra virgin olive oil, whereas a slight increase of the peroxide value was observed only for Glasoil at the end of the observation time without affecting sensory attributes. A general decrease of phytochemicals was observed for extra virgin olive oil and Glasoil, with different reduction trends and degrees depending on the chemical class. A lower stability of Glasoil during shelf-life was confirmed by the worsening of the rheological features and by the polyunsaturated fatty acids reduction (up to −21.71%) with a corresponding increase of the monounsaturated fatty acids/polyunsaturated fatty acids ratio (about +25.69%).

Extra virgin olive oil under simulated consumption conditions: Evaluation of quality, health, and flavour properties

The present study investigated the changes in extra virgin olive oil (EVOO) quality, health, and flavour properties during simulated domestic consumption conditions in which the EVOO bottles were reopened daily, thereby gradually increasing the headspace. Quality parameters, phenolic and volatile compounds, and sensory attributes of two monovarietal EVOOs, Istarska bjelica (IB) and Buža (B), have been evaluated every seven days for one month. After storage, the total phenolic content decreased by 12.3% and 17.6% in IB and B EVOOs, respectively, while the total concentration of volatile compounds decreased by approximately 19%. However, the results have shown that no enhanced degradation of phenolic and volatile compounds has been noted in EVOOs stored under consumption conditions compared to the ones stored unopened during the same period, implying that the degradation degree was predominantly attributed to oil aging. The principal component analysis emphasised peroxide value and sensory attributes as parameters that segregated EVOOs under consumption conditions from the fresh and unopened ones. Furthermore, the conditions in which EVOO was consumed in a recommended daily dosage (20 g) during one-month storage did not reduce its phenolic content under the levels required for the EFSA health claim application.

Treated Unconventional Waters Combined with Different Irrigation Strategies Affect 1H NMR Metabolic Profile of a Monovarietal Extra Virgin Olive Oil

The agricultural sector is facing a decrease in water supply and water quality at a global level and this is a problem that strictly affects all the Mediterranean olive growing areas. The aim of this work was to evaluate, for the first time, by NMR Spectroscopy and multivariate data analysis the metabolic profiling of the oils produced under different irrigation schemes. Arbosana olive oils were obtained from the use of saline reclaimed water (RW) and treated municipal wastewater (DW), combined with: full irrigation (FI) and regulated deficit irrigation (RDI). The results show a higher relative content of saturated fatty acids in EVOOs obtained from RDI strategy, regardless of the water source. Moreover, an increase in unsaturated fatty acids, a ω6/ω3 ratio content was observed in EVOOs obtained from RW when compared with DW water. Furthermore, the RW–RDI showed an increase in secoiridoid derivatives and hydroperoxides with respect to DW–RDI. A sustainable irrigation management, by combining a deficit irrigation strategy and saline reclaimed water source, could be crucial in order to overcome the problem of water scarcity and to guarantee the olive oil nutraceutical properties. The 1H NMR-based metabolomic approach proved a powerful and versatile tool for this specific investigation.

The addition of Capsicum baccatum to Calabrian monovarietal extra virgin olive oils leads to flavoured olive oils with enhanced oxidative stability

This study aimed to evaluate the influence of Capsicum baccatum L. Aji Angelo and Bishop crown cultivars to the quality parameters of flavoured olive oils (FOOs) obtained by the addition of both fresh and dried pepper powders (1%) to Dolce di Rossano and Roggianella monovarietal extra virgin olive oils (EVOOs). First, pepper extracts were investigated for their total phenolic, flavonoid, carotenoid content as well as phenolic acids, fatty acid profile, and vitamin C and E content. In order to evaluate the impact of both fresh and dried peppers on the oxidative stability of FOOs, the Rancimat test was applied. 2,2-Azinobis(3-ethylbenzothiazoline-6-sulfonic) acid (ABTS), 2,2-diphenyl-1-picrylhydrazyl (DPPH), ?-carotene bleaching (B-CB) and ferric reducing antioxidant power (FRAP) assays were used to investigate the antioxidant potential. Bishop crown dried extracts showed the highest phenolic, carotenoid and vitamin content, whereas Aji Angelo had the highest amount of capsaicinoids. Among EVOOs, Roggianella EVOO showed the highest antioxidant activity as well as the highest induction time (39.6 h). Remarkably, FOO obtained by the addition of Bishop crown dried pepper extract to Roggianella EVOO showed a higher induction time (44.9 h) with respect to the corresponding EVOO.

Evaluation and Origin Discrimination of Two Monocultivar Extra Virgin Olive Oils, Cultivated in the Coastline Part of North-Western Greece

Extra virgin olive oil (EVOO) quality and authenticity are important and challenging factors nowadays for the assurance of consumers’ protection, prevention of unfair competition, and disruption of the national economy by a false declaration of origin. Hence, the recognition of EVOO authenticity is of great interest in terms of commercial and quality aspects. The objective of this study was to evaluate and discriminate monovarietal extra virgin olive oils of the two dominant olive cultivars, Lianolia Kerkyras and Koroneiki, produced in the coastline part of Western Greece, based on their chemical characteristics, followed by statistical and chemometric analysis in order to profile for the first time the typical characteristics of Lianolia Kerkyras as well as to identify possible markers for authenticity purpose. A total of 104 olive oil samples were collected. Both cultivars had an overall high quality profile as far as their basic qualitative parameters (free fatty acid, peroxide value, and UV spectrometric indices) are concerned. A higher concentration in the mono-unsaturated oleic acid characterize olive oils of cv. Koroneiki compared to cv. Lianolia Kerkyras, while a clearly higher concentration in the poly-unsaturated linoleic acid was observed in olive oils of cv. Lianolia Kerkyras. In addition, olive oil samples of cv. Koroneiki showed a clear lower total sterols concentration with a percentage of 40.9% not surpassing the required EU Regulatory limit of 1000 mg/kg, an observation which strengthens previous published results of our research group and depicts an overall “intrinsic characteristic” of cv. Koroneiki. As far as the profile of the individual sterols is concerned, Lianolia Kerkyras samples exhibited higher mean value for the total sterol content as well as for β-sitosterol, the major phytosterol in olive oils, compared to the relative values of Koroneiki. Significant differences in the sterolic and fatty acid composition of the examined olive oil samples were shown by means of statistical analysis demonstrating a strong botanical effect and depicting that those compositional markers can be suggested as possible authenticity tools.

Quality parameters, chemical compositions and antioxidant activities of Calabrian (Italy) monovarietal extra virgin olive oils from autochthonous (Ottobratica) and allochthonous (Coratina, Leccino, and Nocellara Del Belice) varieties

Extra virgin olive oil (EVOO) is the main fat used in the Mediterranean diet. In this work, four monovarietal EVOOs from Calabria (South of Italy) namely Coratina, Ottobratica, Leccino, and Nocellara del Belice and Ottobratica from Calabria (Southern Italy) were investigated for their quality and CIELab parameters as well as antioxidant activity. Statistical significant differences were evidenced among investigated samples. Ottobratica EVOO showed the highest oxidative stability with a protective index (PI) of 29.52 h. This autochthonous cultivar was characterized by the highest total phenols content (452.44 mg of gallic acid/kg of oil) and α-tocopherol content (175.15 ppm) as well as the most promising antioxidant activity with a RACI value of − 0.18. Results evidenced that all the investigated Calabrian EVOOs are characterized by a good physico-chemical quality well within the limits indicated by the regulations issued by the European Union and by the International Olive Council for an EVOO and, also, by a promising healthy properties due their content in bioactive compounds.

Varietal and Geographical Discrimination of Greek Monovarietal Extra Virgin Olive Oils Based on Squalene, Tocopherol, and Fatty Acid Composition.

Extra virgin olive oil (EVOO) is an important component of the Mediterranean diet and a highly priced product. Despite the strict legislation to protect it from fraudulent practices, there is an increasing demand to characterize EVOOs and evaluate their authenticity. For this purpose, 68 monovarietal EVOOs, originating from three regions of Greece (Peloponnese, Crete, and Lesvos) and two local cultivars (Koroneiki and Kolovi), were obtained during the harvesting period of 2018–2019. Fatty acids, squalene, and tocopherols were determined chromatographically according to official methods in order to study the effect of cultivar and geographical origin. Squalene and γ-tocopherol differed significantly amongst the cultivars tested. Koroneiki samples exhibited higher squalene content than Kolovi samples, whereas the opposite was observed for γ-tocopherol. The tocopherol level was highly geographical dependent, with EVOOs from Peloponnese displaying the highest concentration of α-tocopherol, whereas the content of γ-tocopherol was significantly higher in samples from Lesvos. Unsupervised and supervised multivariate analysis resulted in a satisfactory grouping of EVOOs according to cultivar. γ-Tocopherol, squalene, and the majority of fatty acids were the most discriminant variables, with γ-tocopherol, linoleic, linolenic, and gadoleic acid being present at higher levels in samples from the Kolovi cultivar. Koroneiki samples were characterized with higher levels of squalene, palmitic, palmitoleic, and arachidic acid.

Eleven Monovarietal Extra Virgin Olive Oils from Olives Grown and Processed under the Same Conditions: Effect of the Cultivar on the Chemical Composition and Sensory Traits.

Eleven Italian monovarietal extra virgin olive oils (MEVOOs) (Carboncella, Coratina, Frantoio, Leccino, Marzio, Maurino, Moraiolo, Piantone di Falerone, Pendolino, Rosciola, Sargano di Fermo) from olives grown in the same experimental olive orchard, under the same conditions (fertilization, irrigation), and processed with the same technology (three-way continuous plant) were investigated. As a result, the impact of the olive cultivar on fatty acid and triacylglycerols composition, oxidative stability, polar phenolic profile and sensory properties (panel test) of the oil was assessed. Pendolino, Maurino and Marzio oils presented the highest levels (p < 0.01) of palmitic, linoleic and linolenic acids % and the lowest oleic:linoleic ratio. Within triacylglycerols, triolein (OOO) strongly varied among the oils, with Coratina and Leccino having the highest content. Frantoio showed the lowest 1-Stearoyl-2-palmitoyl-3-oleylglycerol and 1,3-Distearoyl-2-oleylglycerol amounts. Rosciola showed the highest level (p < 0.01) for two of the most abundant secoiridoid derivatives (the dialdehydic forms of decarboxymethyl elenolic acid linked to hydroxytyrosol and tyrosol). A good correlation was found between total phenolic content and oxidative stability, indicating Marzio and Leccino respectively as the richest and poorest genotypes. Sensory variability among varieties was mainly linked to perceived bitterness, pungency and fruitiness, while no effects were found on secondary flavors.

Phenolic Profile and Thermal Stability of Monovarietal Extra Virgin Olive Oils Based on Synchronous Fluorescence Spectroscopy.

The olive oil production in Pakistan has recently been started with the cultivation of exotic cultivars that are successfully adapted at Barani Agriculture Research center (BARI), Chakwal, Pakistan in Potohar valley. Therefore, characterization of extra virgin olive oil (EVOO) from this agro-climatic region is mandatory in establishing its biochemical profile and thermal stability. Seventeen monovarietal EVOOs extracted from these cultivars were analysed using synchronous fluorescence spectroscopy (SFS) and subjected to heating at 115, 150 and 170°C for 15min to identify their thermal stability. SFS emission spectra differentiated EVOOs on the basis of phenolic compounds that are denatured at high temperature, further chlorophyll contents also decreased with increasing temperature. The strong emission at ca. 351nm, suggested to be vanillic acid, 391-471nm for blue green region (BGR) assigned to other phenolic compounds and two peaks at 672 and 723nm for chlorophyll became the bases for grouping through Hierarchical clustering. Most of the EVOOs were stable at 150°C but showed denatured spectra at 170°C, the only EVOO extracted from Spanish cultivar Arbequina was found to have moderate fluorescence emission from both vanillic acid and BGR that are more likely to impart oxidative stability even after heating at 170°C, also confirmed by lowest values of specific extinction co-efficient (K232 and K270). Moreover, variation in phenolic contents of Arbequina EVOO was observed with different harvesting stages and the early harvested olives produced more thermally stable oil as compared to late harvested olives. Arbequina oil grown in Pakistan can be better suited for cooking at high temperatures, moreover can be blended with other monovarietal EVOOs to enhance the nutritional benefits and thermal stability.

Chemical and Sensory Profiling of Monovarietal Extra Virgin Olive Oils from the Italian Marche Region.

Chemical and sensory peculiarities of monovarietal extra virgin olive oils (MEVOOs) from the cultivars (cvs.) Ascolana tenera (ASC), Coroncina (COR), Mignola (MIG), Piantone di Mogliano (MOG), and Raggia (RAG) from Marche region (Italy) are investigated. Their polar phenolic substances and α-tocopherol are analysed through high performance liquid chromatography with different detectors. Volatile substances, fatty acid composition, and squalene are analysed by gas chromatography coupled to mass spectrometry (MS) and to the flame ionization detector, respectively. Total antioxidant activity and sensory analysis were also performed. MOG showed high squalene content (on average 0.88 ± 0.16 g/100 g), high relative amount of α-copaene among volatiles, and the highest oleic acid percentage. MIG had high α-tocopherol content (on average 350.0 ± 57.6 mg kg−1) and high α-farnesene in the volatile fraction. ASC showed the highest sensory quality and the lignan pinoresinol with higher concentration as compared to the other MEVOOs (p < 0.05), which resulted in a possible chemical marker for this cv. RAG was characterized by the sensory note of almond, which corresponds to its highest (E)-2-hexenal percentage. Sensory analysis and an antioxidant activity assay performed on a set of industrial extra virgin olive oils purchased in supermarkets, highlighted MEVOOs’ superiority from these points of view. Principal component analysis displays the main characteristics of the cvs. investigated.