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.
Olive oil commercialization has a great impact on the economy of several countries, namely Tunisia, being prone to frauds. Therefore, it is important to establish analytical techniques to ensure ...labeling correctness concerning olive oil quality and olive cultivar. Traditional analytical techniques are quite expensive, time consuming and hardly applied in situ, considering the harsh environments of the olive industry. In this work, the feasibility of applying a potentiometric electronic tongue with cross-sensitivity lipid membranes to discriminate Tunisian olive oils according to their quality level (i.e., extra virgin, virgin or lampante olive oils) or autochthonous olive cultivar (i.e., cv Chétoui and cv Shali) was evaluated for the first time. Linear discrimination analysis coupled with the simulated annealing variable selection algorithm showed that the signal profiles of olive oils’ hydroethanolic extracts allowed olive oils discrimination according to physicochemical quality level (classification model based on 25 signals enabling 84 ± 9% correct classifications for repeated
K
-fold cross-validation), and olive cultivar (classification model based on 20 signals with an average sensitivity of 94 ± 6% for repeated
K
-fold cross-validation), regardless of the geographical origin and olive variety or the olive quality, respectively. The results confirmed, for the first time, the potential discrimination of the electronic tongue, attributed to the observed quantitative response (sensitivities ranging from −66.6 to +57.7 mV/decade) of the E-tongue multi-sensors towards standard solutions of polar compounds (aldehydes, esters and alcohols) usually found in olive oils and that are related to their sensory positive attributes like green and fruity.
In order to guarantee food integrity, testing methods should also include the tools needed to verify the geographical origin described on the label. In the particular case of virgin olive oil (VOO), ...regulatory bodies have yet to establish a standard for geographical identification. This manuscript describes a procedure based on Raman spectroscopy to identify the provenance of these oils based on a classification criterion (European vs non‐European VOOs). The sample collection is considered a relevant step in which multiple factors are taken into account (cultivar distribution, complexity of production in each location, new agricultural practices, and new/old cultivars). A total of 78 virgin olive oils collected around the world allow checking the classification accuracy of the model for identifying sample origin. The PLS‐model built around the Raman spectroscopic data is validated with a blind set of samples, and the results are evaluated in terms of false negative and false positive quality parameters. This study provides an analytical application to detect mislabeling and fraudulent practices related to the geographical provenance of virgin olive oils declared on the labels.
Practical Applications: The results of this study provide a robust mathematical model to assess the origin of virgin olive oils (EU vs non‐EU) based on spectroscopic data. Nowadays, the extensive knowledge of olive oil chemical composition has proven that this composition varies according to pedoclimatic conditions, while non‐targeted methods can be proposed in geographical traceability for their ability to analyze the chemical profile of samples. However, it was deemed necessary to conduct a study through a collaborative work initiative. Thus, this study provides a strict evaluation of Raman spectroscopy through a defined strategy for evaluating non‐targeted methods for geographical identification.
European regulation demands analytical methods that guarantee the geographical origin of virgin olive oils. Raman spectroscopy is presented as a tool to discriminate between European and non‐European virgin olive oils.
The aim of this work is to evidence the quality of four monovarietal olive oils (Carolea, Grossa di Gerace, Ottobratica, and Sinopolese cv) produced at two crop years and at different harvesting ...times in Calabria region, located in the South of Italy. Qualitative parameters of oils are evaluated by analysis of major and minor components, in particular: free acidity, peroxide value, fatty acid composition, sterol composition, total polar phenolic compounds and tocopherols, and total pigments. The total antioxidant activity of olive oils is evaluated by DPPH and ABTS assays. Two variables are evaluated in the statistical data elaboration: the cultivar and the harvesting time. Their effect is studied on the chemical parameters and antioxidant components. The harvesting at October and November did not reduce the quality of two monovarietal olive oils (Carolea and Sinopolese) produced in Calabria, whereas Ottobratica and Grossa di Gerace olive oils produced at November have a lower quality. However, a reduction of qualitative parameters is observed in extra virgin olive oils produced from lately harvested olives with some differences among cultivars.
Practical Applications: Practical application for the study entitled “Effect of the harvesting time on the quality of olive oils produced in Calabria” regards the study of chemical composition on olive oils produced under a controlled experimental procedure. Varietal characteristics and environmental variables affect in general the quality of the olive productions and the obtained olive oils. The results of this work show that the considered harvesting times did not involve a decay of quality on Carolea and Sinopolese olive oils produced in the South of Italy, obtained following right processing procedures.
Under controlled processing procedures, the olive oil quality varies among cultivars mainly from the effect of the considered harvesting periods.
Under controlled processing procedures, the olive oil quality varies among cultivars mainly from the effect of the considered harvesting periods.
Red chili pepper represents an excellent source of functional bioactive compounds, and its use as food additive could be useful for protecting other products from spoilage. Olive oils show a limited ...shelf-life due to a progressive quality deterioration linked mostly to oxidation reactions providing a loss of quality in terms of organoleptic and healthy properties. In this work, the addition of red chili pepper powder to virgin, extra-virgin olive and sunflower oils was proved to be effective in improving their stability during 12 months of shelf-life. Oil stability was monitored by employing the Oxitest system, based on accelerating the oxidation process. Three pepper powders of different pungency were added to the virgin olive oil samples with the aim of investigating whether capsaicinoids could be responsible for the observed effects. The strongest effect was recorded when employing the less pungent pepper showing that the protective effect could not be attributed to the capsaicinoids content. Besides, a screening on different oils demonstrated that the less stable samples received a stronger protective effect. The evaluation of a possible dose-effect relation was also carried out pointing out that a threshold dose of about 1 % was required to record an effect. The results suggest potential perspectives in the field of food technology, as addition of a small amount of sweet pepper could be proposed to prolong food shelf-life.
•The influence of the number of plants/hectare on cv. Arbequina olive oils was studied.•A high-density olive grove located in a non-traditional producing area was selected.•Quality and chemical ...parameters were influenced by tree density.•Crop year affected significantly the overall chemical profile of the olive oils.
The number of plants per hectare is a key factor for olive tree productivity. Nevertheless, information about the effect of tree density on olive oil quality and composition is scarce. Thus, the effect of planting densities of cv. Arbequina trees on olive oil quality and composition was studied along the first four years of production. Two types of planting tree arrangements were evaluated, namely olive trees planted at different distances within a row (2.0 m; 1.5 m; 1.25 m; and 1.0 m, fixing the space between rows equal to 4.0 m) or at different distances between rows (4.0 m; 3.5 m; and 3.0 m, fixing the space within the same row at 1.5 m), which led to planting densities from 1250 to 2500 trees ha−1. The results indicated that the quality parameters, composition, antioxidant activity and oxidative stability were significantly affected by the densities of plants and the crop year (P-value < 0.0001, for one-way ANOVA). An increase of plants in the row and between rows showed a tendency for a slight increase of free acidity, and a reduction of the peroxide value and of the extinction specific coefficients. Fatty acid composition was also affected, with a tendency for the decrease of C16:0, C18:0, SFA and PUFA, and an increase of C18:1, C18:2 and MUFA. The antioxidant activity and the oxidative stability also showed a reduction trend. For all parameters evaluated, the crop year had a marked influence. The year of production had significant statistical effects on the evaluated parameters, which could be related to agro-climatic factors.
Olive fruits from 19 varieties and different areas of Béjaïa province (Algeria) were used to produce monovarietal olive oils in laboratory. The olive oils were analyzed using both traditional ...chemical analyses and nuclear magnetic resonance (NMR) methodology. The investigation involved pigment content determination, tocopherol analysis, fatty acid composition, and chromatographic determination of phenolic compounds. Chlorophyll, carotenoids, tocopherols and the content of oleic acid turned out to be variety dependent. The extra-virgin olive oils (EVOOs) were analyzed as a whole and as phenolic extract by NMR. The study gave general indication on olive oil quality and information about geographical origin of the samples. Overall, the results obtained in the present work reveal that Algerian monovarietal olive oils produced in Béjaïa province have the potential to produce blends that may compete with other Mediterranean products.
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•An in-depth traditional chemical analysis of Algerian olive oils has been performed.•A fingerprinting NMR analysis of the whole oils and their phenolic extract has been proposed.•Some of the analyzed oils are of a very high-quality and they may constitute a good source of healthy compounds in the diet.
Within extra-virgin olive oil (EVOO) global market, there is a niche market of olive oils flavoured with aromatic and medicinal plants. The use of aromatic and medicinal plants to flavour ...extra-virgin olive oils enriches the oil both from a sensorial and nutritional point of view, affecting its chemical composition. It is, therefore, necessary to develop analytical techniques useful to investigate in deeply the quali-quantitative profile of molecules contained in both the volatile and non-volatile fractions of extra-virgin olive oil. In the current study, several flavoured EVOOs (with truffle, basil, cardamom, bergamot, lemon, mandarin, sage, porcini mushroom, garlic, and rose) were purchased from local stores and analysed by both HPLC and GC methods to verify the correspondence with the profile of the added aroma. Furthermore, considering the preciousness and cost of some specific flavouring ingredients, in some cases, multidimensional gas chromatographic approach coupled to IRMS or performed by a chiral separation (Es-MDGC) was led to investigate their authenticity. From the results obtained, these complementary approaches allowed confirming the genuineness for most of the flavoured EVOOs. For few flavourings, some differences were detected with respect to literature references, thus requiring additional analytical devices to further authenticate their genuineness.
Olive oil is a valuable food product, a source of monounsaturated fatty acids, antioxidants, including polyphenolic nature, as well as terpenes and phytosterols. The high cost, along with the demand ...for special dietary properties, makes olive oils an attractive target for counterfeiting, most often done by diluting olive oil with cheaper sunflower and rapeseed oils. Considering that traditional indicators of identification of vegetable oils do not allow to detect such falsification; it is relevant to search for new objective indicators and methods for identifying olive oils. The purpose of the research is to justify the use of triacylglyceride profile for identification and detection of falsification of olive oils. The objectives of the research include the selection and adaptation of an effective and affordable method for determining the triacylglyceride profile; identification of reliable markers of identification and falsification of olive oils, carried out by diluting them with sunflower or rapeseed oils; establishing dependencies that allow determining the amount of sunflower or rapeseed oil mixed with olive oil. Gas chromatography with a flame ionization detector has been used as the main research method. Based on the studies carried out, the method of gas chromatography with a flame initiation detector has been adapted for the analysis of the triacylglyceride profile of olive, sunflower and rapeseed oils, as well as their mixtures. Markers have been established that make it possible to unambiguously identify the falsification of olive oil by diluting it with sunflower or rapeseed oil. Calibration graphs and dependencies are proposed that allow you to set the amount of sunflower or rapeseed oil in a mixture with olive oil.
Biodeterioration plays a significant role in the damage and loss of monuments including gypsum work. Bacteria and fungi are mainly responsible for the biodeterioration of gypsum work. Thus, the ...present study aimed to evaluate the effects of essential oils (Thyme, clove, cinnamon, garlic, castor, and olive) on the growth of the main fungi and bacteria which isolated from the Nujoumi Dome which is also called the Dome of the Toshka Martyrs and is located in Aswan, Egypt. Microbial swabs were taken from these infected objects, and the isolated microorganisms were characterized. The next genera were identified: four fungal isolates were isolated and identified as Aspergillus japonicas, Aspergillus terrus, Penicillium commune, and Cladosporium elatum while two species of bacteria were isolated, identified as Bacillus cereus and Listeria monocytogenes. Garlic oil had the best effect on all isolates, showing 35 and 33 mm inhibition of growth of Bacillus cereus and Listeria monocytogenes, respectively, while 28 mm inhabitation of growth of Penicillium commune, 25 mm inhibition of Aspergillus japonicas, and finally 20 mm inhibition of both Aspergillus terrus and Cladosporium elatum. In conclusion, garlic oil could be an effective natural product for controlling the biodeterioration.
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