High-quality Extra Virgin Olive Oils Research Articles

Factors that Affect the Quality of Olive Oil Produced Using Olives from Traditional Orchards in the Middle East

Traditional olive (Olea europaea) orchards have been grown for thousands of years and still occupy most of the world’s cultivated olive areas. To compete with olive oil produced in the higher-yielding intensive orchards, the oil from traditional orchards must be of high quality. We evaluated oil quality—potential and actual (under commercial conditions)—and tested the stages in the production chain that are likely to reduce oil quality in the traditional sector in the Middle East region. Our findings show a clear negative impact of growers’ traditional practices on both the chemical and sensory characteristics of olive oil. The oil originating from the commercial process had higher free fatty acid and lower polyphenol and carotenoid contents, lower stability, lower pungency, lower fruitiness, lower bitterness, and a higher prevalence of organoleptic defects than oil that originated from fruit picked from the same trees during the experimental procedure. The current common harvesting technique of pole beating significantly increased fruit injury and fruit with mold, leading to a reduction in oil polyphenols and an increase in free fatty acid levels compared with those resulting from manual picking. In addition, after harvest, storing the fruit for more than 48 hours in plastic bags dramatically reduced the oil quality. The traditional olive orchard could be a source of high-quality extra virgin olive oil. However, fruit handling—from the trees until the end of the oil extraction process—is performed incorrectly, thus adversely affecting the oil quality.

An Appraisal of the Oleocanthal-Rich Extra Virgin Olive Oil (EVOO) and Its Potential Anticancer and Neuroprotective Properties.

Dietary consumption of olive oil represents a key pillar of the Mediterranean diet, which has been shown to exert beneficial effects on human health, such as the prevention of chronic non-communicable diseases like cancers and neurodegenerative diseases, among others. These health benefits are partly mediated by the high-quality extra virgin olive oil (EVOO), which is produced mostly in Mediterranean countries and is directly made from olives, the fruit of the olive tree (Olea europaea L.). Preclinical evidence supports the existence of antioxidant and anti-inflammatory properties exerted by the polyphenol oleocanthal, which belongs to the EVOO minor polar compound subclass of secoiridoids (like oleuropein). This narrative review aims to describe the antioxidant and anti-inflammatory properties of oleocanthal, as well as the potential anticancer and neuroprotective actions of this polyphenol. Based on recent evidence, we also discuss the reasons underlying the need to include the concentrations of oleocanthal and other polyphenols in the EVOO's nutrition facts label. Finally, we report our personal experience in the production of a certified organic EVOO with a "Protected Designation of Origin" (PDO), which was obtained from olives of three different cultivars (Rotondella, Frantoio, and Leccino) harvested in geographical areas located a short distance from one another (villages' names: Gorga and Camella) within the Southern Italy "Cilento, Vallo di Diano and Alburni National Park" of the Campania Region (Province of Salerno, Italy).

Sealing Wax and Bottles in Bags-A Paradigm Shift in Refined Olive Oil Packaging: Preliminary Results.

Generally, olive oil possesses natural protection against oxidation due to antioxidant compounds such as phenols and tocopherols. However, in the case of refined olive oil, the refining process unavoidably reduces the presence of these compounds. Considering these considerations, the objective of this study was to address the issues related to the "tightness" of the cap used for packaging oil in SALOV, aiming to extend the product's shelf life. The oil under investigation was packaged in 250 mL transparent glass bottles, each filled with either argon or air. Subsequently, the samples were divided into three groups: one group sealed with a conventional screw cap, another covered with a special protective bag, and a third one sealed with a wax cover directly on the cap. The storage period varied, during which the atmospheric conditions were monitored daily through both destructive and non-destructive analyses. The preliminary results indicate that alternative preservation techniques, such as the use of argon, sealing wax, and protective bags, can effectively enhance the shelf life of the oil and maintain its quality (reduce oxidation, preserve phenolic compounds, and reduce the degradation of pigments). Further research and development in this area could lead to the production of high-quality extra virgin olive oils with extended shelf life and improved sensory and nutritional properties.

Direct analysis in real time of high-quality extra virgin olive oils for the rapid and automatic identification of origin trademark.

Following our previous research on the differentiation of Italian extra virgin olive oils (EVOOs) by rapid evaporative ionization mass spectrometry coupled to a tandem high resolution mass analyser, the present study deals with the evaluation of another direct mass spectrometry (direct-MS) approach for the rapid and automatic discrimination of EVOOs. In particular, direct analysis in real time (DART-MS) was explored as an ambient MS (AMS) source for the building of a top-quality Italian EVOOs database and fast identification of unknown samples. A single quadrupole detector (QDa) was coupled with DART, taking advantage of a cost-saving, user-friendly and less sophisticated instrumental setup. Particularly, quickstrip cards, located on a moving rail holder, were employed, allowing for the direct analysis of 12 EVOO spots in a total analysis time of 6 min. The aim was to develop a reliable statistical model by applying principal component and linear discriminant analyses to clusterize and classify EVOOs according to geographical origin and cultivar, as main factors determining their nutritional and sensory profiles. Satisfactory results were achieved in terms of identification reliability of unknown EVOOs, as well as false positive risk, thus confirming that the use of AMS combined with chemometrics is a powerful tool against fraudulent activities, without the need for mass accuracy data, which would increase the analysis cost. A DART ionization source with a compact and reliable QDa MS analyser allowed for rapid fingerprinting analysis. Furthermore, MS spectra provided quali-quantitative information successfully related to EVOO differentiation. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Aromatic, Sensory, and Fatty Acid Profiles of Arbequina Extra Virgin Olive Oils Produced Using Different Malaxation Conditions.

The demand for high-quality extra virgin olive oil (EVOO) is growing due to its unique characteristics. The aroma and flavor of EVOO depend on its content of volatile organic compounds (VOCs), whose formation is affected by the olive variety and maturity index, and the oil production process. In this study, the sensory quality and VOC and fatty acid (FA) profiles were determined in Arbequina olive oils produced by applying different malaxation parameters (20, 25, and 30 °C, and 30 and 45 min). All the olive oils were classified as EVOO by a sensory panel, regardless of the production conditions. However, cold extraction at 20 °C resulted in more positive sensory attributes (complexity). The FA concentration increased significantly with the malaxation temperature, although the percentage profile remained unaltered. Finally, an OPLS-DA model was generated to identify the discriminating variables that separated the samples according to the malaxation temperature. In conclusion, the tested range of malaxation parameters appeared not to degrade the distinctive attributes/organoleptic profile of olive oil and could be applied to obtain an EVOO of high sensory quality, especially at 20 °C.

Delineating unique and discriminant chemical traits in Brazilian and Italian extra-virgin olive oils by quantitative 2D-fingerprinting and pattern recognition algorithms

Brazil is the second-largest importer, after the United States, of extra-virgin olive oils with an internal production that just reaches 0.25 % of the volume imported and consumed. Information about diagnostic chemical signatures characterizing Brazilian oils is lacking, especially as related to geographical markers and key-aroma compounds distribution. This study fills this gap; by comprehensive two-dimensional gas chromatography (GC×GC) combined with headspace solid-phase microextraction (HS-SPME) and parallel detection (MS/FID), diagnostic quali-quantitative signatures of volatiles from Brazilian oils are obtained. Comprehensively mapping of untargeted and targeted (UT) features through fingerprinting algorithms provides effective classification models, benchmarking Brazilian oils (n = 28) vs. a large selection of Italian high-quality extra-virgin olive oils (n = 111). Identitation of Brazilian oils is achieved by combining six different feature selection strategies, the resulting pattern of predictors includes: 1-methoxy-2-propanol, ethyl acetate, (E)-4,8-dimethyl-1,3,7-nonatriene, propanoic acid, limonene, (E)-2-hexenal, hexanoic acid, pentanal, butanoic acid, hexanal, α-pinene, (E)-β-ocimene, and propanal. Compositional differences also are evidenced in composite-class images resembling 2D patterns characteristic of the two production areas. Quantitative fingerprinting, resembling an artificial intelligence smelling machine, characterizes the unique aroma with 1-penten-3-one and (Z)− 3-hexenal, dominating with pungent and green notes, followed by (E)− 2-hexenal (bitter-almond), (E,E)− 2,4-heptadienal (fatty), eucalyptol (herbal), benzaldehyde (almond), hexanal (green), and (E)− 2-hexen-1-ol (green grass).

Extra virgin olive oil: A comprehensive review of efforts to ensure its authenticity, traceability, and safety.

The growing demand for extra virgin olive oil (EVOO), appreciated for its unique organoleptic properties and health benefits, has led to various fraudulent practices to maximize profits, including dilution with lower value edible oils. The adulterated oils would be of poor nutritional quality, more readily oxidized, and may contain unhealthy substances formed during processing. Nevertheless, the range of available techniques to detect fraud in EVOO production has been growing. Reliable markers of EVOO adulteration include fatty acids and minor components such as sterols, tocopherols, triterpene alcohols, phenolic compounds, phospholipids, volatile compounds, and pigments. Additionally, increasing consumer interest in high-quality EVOO has led to the development of robust scientific methods for its traceability. This review focuses on (i) the usefulness of certain compounds as markers of EVOO adulteration; (ii) the potential health risks of consuming adulterated EVOO; and (iii) reliable methods for the geographical traceability of olive oil. In conclusion, fraudulent production practices need to be detected to preserve the beneficial health effects of EVOO and to avoid the potential risks associated with ingesting substandard oil. In this work, as EVOO certification and regulatory framework limitations have already been extensively reviewed, we focus our attention on biomarkers that guarantee both the authenticity and traceability of oil, and consequently its health properties. When it is unavailable to obtain a high-resolution mass spectrometry full fingerprint, stigmastadienes and the sterolic profile are proposed as reliable markers.

Optimizing the Malaxation Conditions to Produce an Arbequina EVOO with High Content of Bioactive Compounds.

To meet the growing demand for high-quality extra-virgin olive oil (EVOO) with health-promoting properties and pleasant sensory properties, studies are needed to establish optimal production parameters. Bioactive components of EVOO, including phenolic compounds, carotenoids, chlorophylls, tocopherols, and squalene, contribute to its organoleptic properties and beneficial health effects. The aim of this study was to develop an Arbequina EVOO with high phenol content, particularly oleocanthal and oleacein, on a laboratory scale by analyzing the effects of different temperatures (20, 25, and 30 °C) and times (30 and 45 min) of malaxation. Higher temperatures decreased the levels of the phenolic compounds, secoiridoids, tocopherols, and squalene, but increased the pigments. EVOO with the highest quality was produced using malaxation parameters of 20 °C and 30 min, although oleocanthal and oleacein were higher at 30 and 25 °C, respectively. Overall, 20 °C and 30 min were the processing conditions that most favored the physiological and chemical processes that contribute to higher levels of bioactive compounds in the oil and diminished their degradation and oxidation processes.

Development of a Lab-Scale Prototype for Validating an Innovative Pitting Method of Oil Olives

In olive oil extraction processes, different operating methods used for the preparation of olive pastes significantly affect their rheological characteristics, as well as the extraction yields and qualitative characteristics of the oils. To enhance and improve the characteristics of high-quality EVOOs (Extra Virgin Olive Oils), milling technologies have implemented olive pitting in the preparation of olive pastes to be processed for olive oil extraction. Commonly used pitting machines employ the percussion and centrifugal projection of drupes, which often involve the heating of pastes, breaking of kernels, and emulsion of oils. Aiming to improve olive oil pitting processes, the CREA Research Centre for Engineering and Agri-food Processing in Treviglio, Italy, has conceived an alternative method, which is based on the low-speed constriction and mutual abrasion of drupes inside a rotative working chamber. This paper describes the process that led to the hypothesis of an innovative pitting method and to the validation of the hypothesis through the development of a lab-scale pitter prototype. The development steps and the assessment of the results of the prototype trials are reported.

Characterization of the Key Odorants in High-Quality Extra Virgin Olive Oils and Certified Off-Flavor Oils to Elucidate Aroma Compounds Causing a Rancid Off-Flavor

To identify the odorants responsible for a rancid off-flavor in olive oils, first, the key aroma compounds in a premium extra virgin olive oil (PreOO1) were characterized by the sensomics approach and were then compared to those present in a certified rancid off-flavor olive oil (RanOO1) obtained from the International Olive Council (IOC). By application of an aroma extract dilution analysis, 46 odorants were detected and subsequently identified in PreOO1 and 35 odorants in RanOO1, respectively. After quantitation by stable isotope dilution assays, calculation of odor activity values (OAVs; ratio of concentration to odor threshold) revealed only 5 odorants with OAVs > 10 in PreOO1, while 13 odorants showed OAVs > 100 in RanOO1, with (E,Z)-2,4-decadienal, hexanoic acid, octanal, hexanal, (E)-2-octenal, and (Z)-2-nonenal being among the most odor-active compounds. Thus, marker aroma compounds for this off-flavor type could be suggested. Additionally, based on the OAVs obtained, the overall aroma profiles of both oils were mimicked by aroma recombination experiments. As proof of concept, 16 marker odorants were quantitated in two additional extra virgin olive oils and in eight further olive oils eliciting a rancid off-flavor. Application of a principal component analysis (PCA) and a hierarchical cluster analysis successfully discriminated both categories of olive oils. In the 12 olive oils used, acetic acid showed the highest Pearson coefficient between the perceived intensity of the rancid defect and the odorant concentration. In particular, (E,Z)- and (E,E)-2,4-decadienal and (Z)-2-nonenal can be suggested as chemical markers for olive oil rancidity in combination with positive aroma markers, for example, acetaldehyde and (Z)-3-hexenal.

Consumer Acceptance and Quality Parameters of the Commercial Olive Oils Manufactured with Cultivars Grown in Galicia (NW Spain).

Mansa and Brava are olive autochthonous cultivars from Galicia, a new olive-growing zone from NW Spanish, from which high-quality extra virgin olive oils (EVOOs) are obtained. The oils obtained as by co-crushing Mansa and Brava olives in different proportions as by blending with others olives cultivars have different composition that influence in their sensory quality. The consumer acceptance of commercial oils elaborated with Local Galician cultivars was evaluated and a quality-mapping of olive oils was created. It was found that the both Local oils had good physical-chemical quality parameters. From sensory analysis viewpoint, Local-MB oils presented the highest intensity values for color, odor, taste, and flavor, and the consumers had a higher acceptance and preference by Picual, Local-MBPA (60% Mansa and Brava, 25% Picual, and 15% Arbequina and Local-MB (60% Mansa and 40% Brava) oils. A quality-mapping of olive oils indicate that attributes better scored from the consumer are high intensity for color, odor, taste and flavor, and pungent and floral series, and bitter is rejected by them.

Determination of the Phenol and Tocopherol Content in Italian High-Quality Extra-Virgin Olive Oils by Using LC-MS and Multivariate Data Analysis

Italian extra-virgin olive oil market presents several kinds of products, some of which are of higher quality compared to others. Italian high-quality extra-virgin olive oils can have Protected Designation of Origin, Protected Geographical Identification and organic farming denominations. Each high-quality olive oil produced shows peculiar chemical composition and organoleptic characteristics. The present work was aimed to endorse the use of Italian high-quality extra-virgin olive oils and to promote the “Italian quality olive oil culture” to the consumers. To obtain this, task two analytical methods were developed in order to investigate the phenol and tocopherol contents in one hundred eighty-six high-quality extra-virgin olive oils by using HPLC coupled to mass spectrometry and fluorimetric detection, respectively. Olives milled to obtain these samples belong to forty-seven different cultivars. Furthermore, four different assays were used in order to evaluate antioxidant activity of all samples: TEAC, ORAC, FRAP, and DPPH, while the total phenols content was assessed by the Folin-Ciocalteu method. Finally, all these information were used to make a principal component analysis (PCA) in order to verify a possible correlation between oils belonging to the same region, or to the same cultivar, or to denomination. To the best of our knowledge, this is the first research article that reports the bioactive molecule content and a PCA statistical correlation between total phenol content, antioxidant activity (TEAC, FRAP, DPPH and ORAC), tocopherols and phenols in a large array of Italian high-quality extra-virgin olive oils (174) produced in different regions; in addition a number of 12 samples came from foreign countries (Portugal, Spain and Croatia). The gathered information attained could be useful for the generation of a database of a qualitative and quantitative profile of antioxidant molecules in extra-virgin olive.

Effect of Mediterranean Diet Enriched in High Quality Extra Virgin Olive Oil on Oxidative Stress, Inflammation and Gut Microbiota in Obese and Normal Weight Adult Subjects.

Introduction: The Mediterranean Diet (MD) is useful in the prevention of overweight, obesity and metabolic disease. High Quality-Extra Virgin Olive Oil (HQ-EVOO), an essential component of this diet, exerts protective effects against chronic diseases. Gut Microbiota (GM), recognized as a key factor in driving metabolic activities, is involved in the regulation of host immunity. Lactic Acid Bacteria (LAB) and their probio-active cellular substances produce beneficial effects in the gastrointestinal tract.Materials and Methods: Eighteen overweight/obese subjects (cases, BMI ≥25 kg/m2) and 18 normal weight controls (BMI 18.5–24.9 kg/m2) were fed with MD enriched with 40 g/die HQ-EVOO for three months. Feces and blood samples were collected at time 0 (T0) and after three months (T1) for LAB composition, oxidative stress, metabolic and inflammation parameter determinations.Results: Myeloperoxidase and 8-hydroxy-2-deoxyguanosine, markers of inflammation and oxidative stress, were significantly decreased after MD rich in HQ-EVOO both in controls and in cases. Proinflammatory cytokines levels were significantly decreased in cases in comparison to controls, while IL-10 and adiponectin were significantly increased in cases. LAB’s rpoB copies/ng of DNA increased 55.6 folds in cases compared to their baseline after MD rich in HQ-EVOO. MD rich in HQ-EVOO increased adiponectin and IL-10 concentration in overweight/obese subjects and decreased oxidative stress and inflammation parameters and at the same time, increased LAB number in GM.Discussion: Our results indicate that MD rich in HQ-EVOO induces an increase of LAB in GM and could have a potential role in the prevention of inflammation.Clinical Trial Registration: www.ClinicalTrials.gov, identifier NCT03441802.

Quality evaluation of extra-virgin olive oils from Sicilian genotypes grown in a high-density system

Studying the sensory profile and chemical composition of monovarietal extra-virgin olive oils (EVOOs) is important to define and manage their quality and uniqueness. Chemical and sensory traits of olive oils from 14 minor Sicilian olive genotypes in comparison with oils from six major Sicilian and three international cultivars were analysed. Oils were extracted in 2015 from fruit of the 23 genotypes grown in an experimental orchard at a planting density of 1140 trees ha−1. Fatty acid composition, phenol composition, carotenoid content and antioxidant power were determined and analysed using univariate and multivariate procedures, in particular Nocellara Etnea along with carotenoid, phenol content and good sensory attributes, producing the best quality EVOO among the genotypes in trial. These results show that some Sicilian accessions used in this study may represent valid alternatives to produce high-quality EVOOs in modern, hedgerow planting systems.

Varietal Authentication of Extra Virgin Olive Oils by Triacylglycerols and Volatiles Analysis.

In recent years, there is an increasing interest in high-quality extra virgin olive oils (EVOOs) produced from local cultivars. They have particular chemical/organoleptic characteristics and are frequently subjected to fraud, whereby the control of quality requires a powerful varietal check. In the present research, triacylglycerols (TAGs) and volatiles have been studied as chemical markers for the authentication of EVOO samples from four Italian varieties of Olea europea (Dolce Agogia, Frantoio, Leccino, and Moraiolo). The monocultivar EVOO samples have been subjected to a chemical–enzymatic chromatographic method in order to perform a stereospecific analysis, an important procedure for the characterization of TAG of food products. The results, combined with chemometric analysis (linear discriminant analysis, LDA), were elaborated in order to classify Italian EVOO monocultivar samples. In accordance with the total and intrapositional fatty acid (FA) composition of TAG fraction, the results were allowed to carry out a varietal discrimination. In addition, volatile compounds were also determined by solid-phase micro-extraction gas chromatography-mass spectrometry analysis. All EVOO samples were correctly classified when TAG stereospecific data and volatile results were elaborated by the LDA procedure, even if volatile compounds showed a higher discriminant power.

Environmental impact assessment of three packages for high-quality extra-virgin olive oil

Life cycle assessments of food packaging technologies have shown that they contribute considerably to the environmental impact of products. This study analyses the life cycle impact of three packaging solutions for high-quality extra-virgin olive oil. Two of them are widely used solutions, namely tin plated cans and dimmed glass bottles. The third one is a stainless steel bottle, which has been proposed recently. The analysis was performed with a cradle to grave approach and it takes into account raw materials extraction and processing, packaging production processes and several end-of-life scenarios. Impacts due to distribution were considered separately to assess uncertainties due to distribution distances. The results show that, for same sizes, dimmed glass bottles have the lowest overall impact value for all the six indicators selected except for ozone layer depletion, whereas stainless steel bottles have the highest impact values for all the other indicators. A sensitivity analysis was performed to determine how impact varies in function of distance and packaging weight. It shows that it is possible to set a breakeven point over which the impact of glass overcomes the one of the other packaging systems. Packaging shows a significant contribution to impact of bottled oil. For small packaging, such as a 0.100 L stainless steel bottle, this contribution can be as relevant as 60% of the overall global warming potential.

Sensory analysis and consumer acceptance of 140 high-quality extra virgin olive oils

Sensory analysis is a crucial tool for evaluating the quality of extra virgin olive oils. One aim of such an investigation is to verify if the sensory attributes themselves - which are strictly related to volatile and phenolic compounds - may permit the discrimination of high-quality products obtained by olives of different cultivars and/or grown in various regions. Moreover, a crucial topic is to investigate the interdependency between relevant parameters determining consumer acceptance and objective sensory characteristics evaluated by the panel test. By statistically analysing the sensory results, a grouping - but not discriminatory - effect was shown for some cultivars and some producing areas. The preference map shows that the most appreciated samples by consumers were situated in the direction of the 'ripe fruity' and 'sweet' axis and opposite to the 'bitter' and 'other attributes' (pungent, green fruity, freshly cut grass, green tomato, harmony, persistency) axis. Extra virgin olive oils produced from olives of the same cultivars and grown in the same areas shared similar sensorial attributes. Some differences in terms of expectation and interpretation of sensory characteristics of extra virgin olive oils might be present for consumers and panellists: most of the consumers appear unfamiliar with positive sensorial attributes, such as bitterness and pungency.