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SUMMARY: Advances in olive oil research have blossomed in recent years, and articles on olive oil have been widely recorded. However, a comprehensive and systematic bibliometric analysis of olive oil research has not been completed. Through a systematic literature search, we consolidated 7003 papers from the Web of Science Core Collection database. This bibliometric analysis was carried out to examine the article growth, geographical distribution, and analysis of journals/research areas/authors/keywords. The results revealed the following: (1) Exponential growth was shown in the annual number of publications (R2 = 0.9791). The geographical distribution is biased to a few countries, especially Spain, Italy, and Greece in the Mediterranean region, placing a larger focus on olive oil research. (2) Quality analysis‐related research acted as a link between keyword groups, the disease prevention and treatment‐related research of olive oil received decreasing interest, while authentication and quality analysis‐related research of olive oil showed the opposite trend, by‐products‐related research of olive oil got waving interests over the whole period. (3) Improvement is needed in the degree of olive oil with international collaboration. This is the first time that hotspots and trends in olive oil research have been shown. [ABSTRACT FROM AUTHOR]

Abstract The paper describes the results of a specific LCA based analysis of the production of olive oil in the region of Calabria, in southern Italy. The goal of the study is to assess the energy and environmental impacts of different scenarios involving conventional and organic cultivations, plains and hills cultivations and involving different operating techniques. The study also aims at assessing the share of each life cycle step on the total of energy and environmental impacts. The functional unit chosen for the comparative analysis is a glass bottle of 0.75 L of extra virgin olive oil. A "from cradle to gate" perspective was chosen. The analysis was developed according to the LCA standards of the ISO 14040 series. The analysis is based on a field analysis developed in the last years in the province of Reggio Calabria between more than 50 enterprises and stakeholders of the field, representative of the whole Calabria region and of most southern Italy. The data used for the development of mass and energy balances are related to the years 2013–2015. The results clarify that for all indicators that the first part of the life cycle – from the production, including the growth of the olive plant to the full production stage – is the most relevant, variable between 80.6% share in the case of the particulate matter indicator to the 99.64% in the case of land use (Hill – Biological agriculture scenario). Relevant differences can be also traced for each specific indicator among all scenarios; high impacts are traced for the agricultural stages among all scenarios (70% −90% in all indicators) with high impacts caused by fertilizers. Among the transformation stages the bottle production is one of the most relevant sources of life cycle energy uses and environmental impacts (80–90%). Highlights • A life cycle (LC) assessment for different olive oil production techniques in southern Italy is proposed. • The agricultural stages cause more than 70% of the life cycle environmental impacts. • Bottling is a critical step in terms of environmental impacts among the transformation stages. • Energy efficiency in the transformation stages has only moderate positive impacts in the LC perspective. [ABSTRACT FROM AUTHOR]

The authentication and verification of the geographical origin of food commodities are important topics in the food sector. This study shows the spatial variability in δ 13 C and δ 18 O of 387 samples of Italian extra-virgin olive oil (EVOO) collected from 2009 to 2011. EVOOs’ δ 13 C and δ 18 O values were related to GIS (Geographic Information System) layers of source water δ 18 O and climate data (mean monthly temperature and precipitation, altitude, xerothermic index) to evaluate the impact of the most significant large-scale drivers for the isotopic composition of Italian EVOOs. A geospatial model of δ 18 O and δ 13 C was developed for the authentication and verification of the geographical origin of EVOOs. The geospatial model identified EVOOs from four distinct areas: north, south-central Tyrrhenian, central Adriatic and islands, highlighting the zonation of the expected isotopic signatures. This geospatial approach can be used to define a protocol for analyzing the isotopic composition of EVOOs in order to certify their origin and prevent food fraud. Limits and perspectives of the model are discussed. [ABSTRACT FROM AUTHOR]

In this study extra virgin olive oils of Italian and non-Italian origin (from Spain, Tunisia and blends of EU origin) were differentiated by GC-FID analysis of sterols and esterified sterols followed by chemometric tools. PCA allowed to highlight the high significance of esterified sterols to characterise extra virgin olive oils in relation to their origin. SIMCA provided a sensitivity and specificity of 94.39% and 91.59% respectively; furthermore, an external set of 54 extra virgin olive oils bearing a designation of Italian origin on the labelling was tested by SIMCA. Prediction results were also compared with organoleptic assessment. Finally, the poor correlation found between ethylesters and esterified sterols allowed to hazard the guess, worthy of further investigations, that esterified sterols may prove to be promising in studies of geographical discrimination: indeed they appear to be independent of those factors causing the formation of ethyl esters and related to olive oil production. [ABSTRACT FROM AUTHOR]

Highlights: [•] Analysis of olive oil flavored with truffles by DHS–GC–MS and electronic nose. [•] Blind analysis of oil flavored truffles taken from the Italian market. [•] Detected 63 volatile compounds, 32 from oil, 19 from truffle and 12 of other origin. [•] E-nose was able to discriminate the three species of truffle declared on the label. [•] Confirming the malpractice of the use of bismethyl(dithio)methane. [ABSTRACT FROM AUTHOR]

The fatty alcohol (FAL) composition of olive oils produced in Southwest Calabria (Southern Italy) was analyzed over three harvest years 2005-2006-2007. Three autochthonous cultivars: Cassanese, Ottobratica, Sinopolese and seven allochtonous cultivars: Coratina, Itrana, Leccino, Nocellara Messinese, Nociara, Pendolino and Picholine were considered. Hexacosanol was always the main FAL occurring in the olive oil. The autochthonous cultivars were among those with the highest total FAL contents. Nevertheless, both autochthonous and allochthonous cultivars produced olive oil within the limit indicated by EU and IOC regulations. Cultivar affected the FAL content highly significantly or very highly significantly, whereas in a large part of the cases the harvest year did not influence the FAL content. Cultivar x harvest year influenced highly significantly or very highly significantly only C22-OH, C23-OH, C24-OH, C25-OH, odd chain FALs and the ratio even chain/odd chain FALs. [ABSTRACT FROM AUTHOR]

The interest in development of new non-destructive methods for characterization of extra virgin olive oils (EVOOs) has been increasing in the recent years. Among different experimental techniques, nuclear magnetic resonance (NMR) relaxation measurements are very promising in the field of food characterization and authentication. In this study, we focused on relaxation times T 1 and T 2 relaxometry dispersions directly on olive oil samples without any chemical/physical treatments. A large set of EVOO samples produced in two regions of Italy, Tuscany and Apulia, were investigated by means of 1 H NMR T 1 relaxometry dispersions directly on olive oil samples without any chemical/physical treatments. A large set of EVOO samples produced in two regions of Italy, Tuscany and Apulia, were investigated by means of 1 H NMR relaxation techniques. The relaxation studies reported here show several common features between the two sets of EVOO samples, thus indicating that relaxation properties, namely, the ranges of values of T 1 and T 2 at 2 and 100 MHz, are characteristic of EVOOs, independently from the cultivars, climate, and geographic origin. This is a promising result in view of quality control and monitoring.

The challenging process of high-quality food authentication takes advantage of highly informative chromatographic fingerprinting and its identitation potential. In this study, the unique chemical traits of the complex volatile fraction of extra-virgin olive oils from Italian production are captured by comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry and explored by pattern recognition algorithms. The consistent realignment of untargeted and targeted features of over 73 samples, including oils obtained by different olive cultivars ( n = 24), harvest years ( n = 3), and processing technologies, provides a solid foundation for sample identification and discrimination based on production region ( n = 6). Through a dedicated multivariate statistics workflow, identitation is achieved by two-level partial least-square (PLS) regression, which highlights region diagnostic patterns accounting between 58 and 82 of untargeted and targeted compounds, while sample classification is performed by sequential application of soft independent modeling for class analogy (SIMCA) models, one for each production region. Samples are correctly classified in five of the six single-class models, and quality parameters [i.e., sensitivity, specificity, precision, efficiency, and area under the receiver operating characteristic curve (AUC)] are equal to 1.00.

The cultivar Bianchera is an autochthonous variety from the eastern part of northern Italy, but it is also cultivated in the Slovenian and Croatian peninsula of Istria where it is named Belica (Slovenia) and Bjelica (Croatia). The properties of oleocanthal, a natural anti-inflammatory ibuprofen-like compound found in commercial monocultivar extra virgin olive oils, were determined by means of both quantitative 1H NMR (qNMR) and HPLC analyses, where qNMR was identified as a rapid and reliable method for determining the oleocanthal content. The total phenolic content (TPC) was determined by means of the Folin–Ciocalteau method and the major phenols present in the olive oils were also quantified by means of HPLC analyses. All these analyses confirmed that the cultivar Bianchera was very rich in polyphenols and satisfied the health claim provided by the EU Commission Regulation on the polyphenols content of olive oils and their beneficial effects on human health. [ABSTRACT FROM AUTHOR]

Considering the growing number of extra virgin olive oil (EVOO) producers in the world, knowing the influence of olive oils with different geographical origins on the characteristics of the final blend becomes an interesting goal. The present work is focused on commercial organic EVOO blends obtained by mixing multiple oils from different geographical origins. These blends have been studied by 1 H-NMR spectroscopy supported by multivariate statistical analysis. Specific characteristics of commercial organic EVOO blends originated by mixing oils from Italy, Tunisia, Portugal, Spain, and Greece were found to be associated with the increasing content of the Italian component. A linear progression of the metabolic profile defined characteristics for the analysed samples-up to a plateau level-was found in relation to the content of the main constituent of the Italian oil, the monocultivar Coratina. The Italian constituent percentage appears to be correlated with the fatty acids (oleic) and the polyphenols (tyrosol, hydroxytyrosol, and derivatives) content as major and minor components respectively. These results, which highlight important economic aspects, also show the utility of 1 H-NMR associated with chemometric analysis as a powerful tool in this field. Mixing oils of different national origins, to obtain blends with specific characteristics, could be profitably controlled by this methodology.

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.

Fatty acids, phenolic compounds, and tocopherols of Coratina, Bosana, Semidana, and Tonda di Cagliari virgin olive oils, were measured over a 45-day harvest period. Phenolic composition was the primary factor distinguishing Bosana, Tonda di Cagliari, and Semidana, whereas fatty acids differentiated Coratina and the other cultivars. Harvest period principally influenced oleacein, oleocanthal, oleuropein and ligstroside aglycones, and flavonoids. High phenolic content was observed for Coratina (1039-688 mg/kg) and Bosana (788-592 mg/kg). A drastic decrease in phenolic content was observed in Semidana (529-134 mg/kg) and Tonda di Cagliari (507-142 mg/kg) during the harvest period. These two cultivars also had low MUFA/PUFA (6.0-4.0 and 4.9-3.2 respectively), suggesting that these varieties should be harvested earlier in the season. These results provide information to producers for improved management of the harvesting process, which is strongly affected by varietal factors., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Extra-virgin olive oil (EVOO) is one of the most popular products in Mediterranean diet. Spain produces about 52% of olive oil with the presence of larger firms; Italy follows with a share of 9% and a production structure characterized instead by small family businesses. A social analysis, based on a multiple-questionnaire, has analyzed the perspectives of 500 consumers conferring their olives to a family-owned olive oil mills (OOMs). This work aims to assess the role of family business evaluating the opportunities associated with the development of circular economy (CE) models. Results show that Italian consumers' preferences give attention to the use of natural resource and the olive oil is perceived as a natural product. In addition, family owned-OOMs provide a great sense of trust and the relevant role of family within the entire life cycle of olive oil is demonstrated. OOMs that work for residential market are strongly preferred to industrial ones being able to manage single lots of olives belonging to the same customers' land. The recovery of some by-products represents an opportunity for OOMs and policy support is required to favor the needed generational change, whose absence is perceived as a serious obstacle to the future development of the sector along circularity principles. [ABSTRACT FROM AUTHOR]

In this preliminary study, ultra-high-pressure liquid chromatography (UHPLC) coupled to quadrupole-time-of-flight mass spectrometry (QTOF) metabolomics followed by multivariate statistics was applied to discriminate nine extra-virgin olive oil (EVOO) cultivars according to their phenolic and sterolic fingerprints. The same approach was then used to discriminate EVOO samples from different geographical origins, namely six blends representative of the main growing regions in Italy (i.e., Sicily, Puglia, Umbria, Liguria, Lombardy and Tuscany). This approach allowed to putatively identify >1000 compounds, considering both polyphenols and sterols. The unsupervised hierarchical cluster analysis (HCA) and the orthogonal projections to latent structures discriminant analysis (OPLS-DA) discriminated EVOO samples according to both cultivar and geographical origin. In particular, flavonoids (i.e., anthocyanins and flavonols), hydroxycinnamic acids and cholesterol derivatives were found to be the most representative classes of compounds discriminating EVOO samples according to the two parameters (cultivar or geographical origin) selected. However, the following Venn analysis allowed to point out the discriminant markers being exclusive for cultivar or origin discrimination. In this regard, only the 9.6% of phenolics and 13.6% of sterols were in common, thus indicating that several of these discriminant compounds were exclusive of a single condition. Indeed, considering that most of the commercial EVOOs are blended, the contribution of both the cultivars used and the geographical origin must be taken into account., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Extra virgin olive oil (EVOO) is characterized by its aroma and other sensory attributes. These are determined by the geographical origin of the oil, extraction process, place of cultivation, soil, tree varieties, and storage conditions. In the present work, an array of metal oxide gas sensors (called S3), in combination with the SPME-GC-MS technique, was applied to the discrimination of different types of olive oil (phase 1) and to the identification of four varieties of Garda PDO extra virgin olive oils coming from west and east shores of Lake Garda (phase 2). The chemical analysis method involving SPME-GC-MS provided a complete volatile component of the extra virgin olive oils that was used to relate to the S3 multisensory responses. Furthermore, principal component analysis (PCA) and k-Nearest Neighbors (k-NN) analysis were carried out on the set of data acquired from the sensor array to determine the best sensors for these tasks and to assess the capability of the system to identify various olive oil samples. k-NN classification rates were found to be 94.3% and 94.7% in the two phases, respectively. These first results are encouraging and show a good capability of the S3 instrument to distinguish different oil samples., Competing Interests: The authors declare no conflict of interest.

Mediterranean olive trees have been cultivated in Pakistan for decades to promote olive cultivation and use of olive oil. The qualitative characteristics of seven mono and one multi-varietal extra virgin olive oils (EVOOs) extracted from Italian cultivars grown in different areas of Balochistan a southwestern province of Pakistan were evaluated. Present study aims to assess the impact of bioclimatological change on biochemical profile of exotic cultivars. The dominating fatty acids found in analyzed EVOOs were oleic (65-72%), linoleic (10.61-18.33%) and palmitic acids (12-16%). The tocopherols α, (β+γ) and δ contents showed a great diversity which ranged from (60-408) mg/kg while, total phenol concentration ranged from (200-370) mg/kg. The analyses of phenolic compounds revealed the presence of phenolic acids, phenolic alcohols, secoiridoids, flavonoids, oleuropein and verbascosides. One-way ANOVA revealed significant differences (p < 0.05) regarding studied parameters. Principal component analysis (PCA) was applied to identify the main components and to classify samples into groups in terms of fatty acids and phenolic profiles. The first group (Frantoio, Moraiolo, Pendolino, Multi-varietal mixture) characterized by high amount of oleic acid and MUFAs/PUFAs ratio. The second group (Maurino and Leccino) correlates with SFAs and third (Ottobrattica, Coratina) with PUFAs. Based on the PCA of phenolic profile the studied cultivars were divided into two main groups. Morialo, Pendolino and Maurino correlated with (phenolic acids, hydroxytyrosol, flavonoids and secoiridoids). Frantoio, Ottobrattica, Coratina, multi-varietal and Leccino were correlated with oleuropein, tyrosol and ligstroside aglycon. The obtained data was compared with those obtained from same cultivars in their original and/or different growing area. Marked differences were observed in the composition of oleic, linoleic, palmitic acids, secoiridoids and total phenolic contents. These differences could be due to change in geographical location and climatical condition of Balochistan. The cultivar Moraiolo has shown best adaptation and preserved its biochemical composition among all studied cultivars.

The virgin olive oils (VOOs) under examination were from the main Tunisian cultivar 'Chemlali'. Olive fruits used for oil production were stored in plastic containers for four weeks at ambient temperature. Hydrophilic bioactive compounds and volatile profiles of the corresponding oils were analyzed. Chemometric analysis showed that VOO obtained from fruits stored during one week is similar to that of freshly harvested fruits. They preserved their bioactive and volatile molecular markers of freshness with the predominance of the secoiridoid aldehydic form of oleuropeine aglycon, and the C 6 lipoxygenase products. However, VOO obtained from fruits stored for a long time, showed degradation of the derivatives of oleuropeine and ligstroside aglycons, a decrease in the lignan, and flavonoid groups, whereas phenolic acids showed a remarkable increase. The volatile profile was characterized by a decrease in the LOX products, and biosynthesis of the volatile molecular markers of oxidation C 7 -C 10 aldehydes (nonanal, decanal, (Z) and (E)-2-heptenal, (E)-2-octenal, and (E,E)-2,4-heptadienal), and hydrocarbons (n-dodecane, and n-tetradecane). Mono and sesquiterpenes showed also an increase over storage time. Consequently, and in order to avoid deterioration of VOO composition, chemometric analysis showed that the olive fruits should be processed as soon as possible after being harvested, with a maximum storage time of one week., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

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.)