The Ultrasonic Investigation of Phase Transition in Olive Oil up to 0.7 GPa

This paper presents measurements of sound velocity and attenuation in olive oil, with known chemical composition, as a function of pressure, within the range of pressure up to 0.7 GPa. Dependencies of sound velocity, relative ultrasonic wave attenuation, volume, and adiabatic compressibility on pressure show discontinuities. This proves the existence of the first order phase transition in olive oil (liquid to solid-like phase transition). Rapid and large changes in relative attenuation testify to the existence of a phase transition in olive oil. Moreover, the kinetics of phase transition was also investigated. Measurement of acoustic wave velocity and relative attenuation in olive oil during the phase transition and in the high-pressure phase is a novelty. The results obtained can be useful in the development of new methods in food (edible oils) control, processing, and preservation.     

Chemical Composition of Turkish Olive Oil––Ayvalik

Although large amounts of olive oil are produced in Turkey, not much information on its chemical composition is available in the literature to date. The aim of this study was to evaluate the chemical composition of commercial olive oils produced from the Ayvalik olive cultivar in Canakkale, Turkey. Five different samples corresponding to the olive oil categories of extra virgin (conventional, extra virgin olive oil (EVOO), and organic extra virgin olive oil (OGOO) production), virgin olive oil (OO-1), ordinary virgin olive oil (OO-2) and refined olive oil (RFOO) were evaluated. Olive oils were collected from two consecutive production years. According to the free fatty acids, the absorbance values (K₂₃₂ and K₂₇₀), and peroxide values of all the samples conformed to the European standards for olive oil. The level of oleic acid was in the range of 68–73%; while the linoleic acid content was significantly lower in the refined olive oils. The tocopherol and polyphenol content was in the lower range of some European olive oils. However, pinoresinol was a major phenolic compound (5–77 mg/kg depending on the oil category). Its content was markedly higher than in many other oils, which would be a useful finding for olive oil authentication purposes.     

Hydrolysis of Olive Oil with Immobilized Lipase in a Tapered Column Reactor

Lipase was immobilized in ion exchange resin and then used in the hydrolysis of olive oil to produce fatty acids and glycerol. The time course of hydrolysis of olive oil was investigated in a stirred tank reactor using both of the free and immobilized lipases to find the yield of activity of immobilized enzyme. Continuous hydrolysis of olive oil was also carried out in a tapered column reactor and a cylindrical column reactor with a bottom ID of 10 mm at different upward flow rates. It can be known from experimental results that the degree of hydrolysis of olive oil in the tapered column reactor is moderately better than that in the cylindrical column reactor, the pressure drop in the tapered column reactor is much smaller than that in the cylindrical column reactor.     

Effect of Saturated/Unsaturated Fatty Acid Ratio on Physicochemical Properties of Palm Olein–Olive Oil Blend

Although blending polyunsaturated oil with more saturated or monounsaturated oils has been studied extensively, there is no similar information regarding the partial replacement of palm olein with olive oil (OO). Therefore the main objective of this study was to investigate the effects of OO partial replacement (0, 25, 50, 75, 90 and 100% w/w) on the chemical stability of palm olein oil (POO). The physicochemical properties of oil samples namely iodine value, peroxide value (PV), anisidine value, TOTOX value (total oxidation value, TV), free fatty acid (FFA), cloud point, color and viscosity were considered as response variables. Significant differences among the oil blend properties were determined at the significance level of P < 0.05. Apart from FFA, all the response variables were significantly influenced by type and concentration of oils. The oil blend containing 10% POO and 90% OO showed the highest TV (6.10); whereas the blend containing 90% POO and 10% OO exhibited the least TV (2.41). This study indicated that the chemical stability of oil blend significantly (P < 0.05) increased with increasing the proportion of polyunsaturated/monounsaturated fatty acid.     

Dietary Virgin Olive Oil Reduces Oxidative Stress and Cellular Damage in Rat Brain Slices Subjected to Hypoxia–Reoxygenation

We investigated how virgin olive oil (VOO) affected platelet and hypoxic brain damage in rats. Rats were given VOO orally for 30 days at 0.25 or 0.5 mL kg⁻¹ per day (doses A and B, respectively). Platelet aggregation, thromboxane B₂, 6-keto-PGF_1α, and nitrites + nitrates were measured, and hypoxic damage was evaluated in a hypoxia–reoxygenation assay with fresh brain slices. Oxidative stress, prostaglandin E ₂, nitric oxide pathway activity and lactate dehydrogenase (LDH) activity were also measured. Dose A inhibited platelet aggregation by 36% and thromboxane B₂ by 19%; inhibition by dose B was 47 and 23%, respectively. Virgin olive oil inhibited the reoxygenation-induced increase in lipid peroxidation (57% in control rats vs. 2.5% (P < 0.05) in treated rats), and reduced the decrease in glutathione concentration from 67 to 24% (dose A) and 41% (dose B). Brain prostaglandin E ₂ after reoxygenation was 306% higher in control animals, but the increases in treated rats were only 53% (dose A) and 45% (dose B). The increases in nitric oxide production (213% in controls) and activity of the inducible isoform of nitric oxide synthase (175% in controls) were both smaller in animals given VOO (dose A 84%; dose B 12%). Lactate dehydrogenase activity was reduced by 17% (dose A) and 42% (dose B). In conclusion, VOO modified processes related to thrombogenesis and brain ischemia. It reduced oxidative stress and modulated the inducible isoform of nitric oxide synthase, diminishing platelet aggregation and protecting the brain from the effects of hypoxia–reoxygenation. This study was partially supported by a grant from the Ministerio de Ciencia y Tecnología, Spain (AGL−04-7935-C03-02).     

New Technology to Increase the Rate of Refined Lemon Oil

The technology for the vacuum pyroly-sis of scrap tires developed by the Bio-mass Synthetic Fuel Lab of CASGuangzhou Institute of Energy Conver-     

Quality Characterization of the Olive Oil from Var. Tosca 07® Grown in a Commercial High Density Orchard

A high density olive orchard represents a new planting system that requires cultivars with low vegetative vigor, such as Arbequina and Arbosana varieties. Different cultivars provide different performances in such orchards. This research was performed in order to determine the behavior of the new olive variety Tosca 07^® in a commercial, high density orchard. The quality of Tosca 07^® olive oils in three different maturity degrees during two crops seasons by physico-chemical and nutritional characterization were compared with Arbequina olive oils obtained from trees grown under the same conditions. Tosca 07^® is a very interesting olive variety for high density orchards. Because of its early ripening, it would be suitable for early harvesting, and this could be interesting for avoiding cold temperatures, frost, etc. Tosca 07^® olive oils have also demonstrated a very suitable chemical composition in comparison with Arbequina olive oils, especially for their high content of antioxidant compounds (α-tocopherol and pigments) present within the oils.     

Production of Biocomponent Containing Gas Oil with the Coprocessing of Vegetable Oil�CGas Oil Mixture

We investigated the impact of the enhanced sulphur content of feedstocks during the production of gas oil with bio-component content in one catalytic step, on a NiMo/Al₂O₃ catalyst from sunflower oil-containing gas oil. The mixing of vegetable oil reduces the efficiency of hydrodesulphurization compared to the pure gas oil feedstock, but using the favourable process parameter combination high scale desulphurization can be achieved.     

Canopy Fruit Location Can Affect Olive Oil Quality in ‘Arbequina’ Hedgerow Orchards

The effect of location of fruit in canopies of hedgerow olive trees (Olea europaea L., cv. ‘Arbequina’) on quality of virgin oil was tested by analyzing oils extracted from different height layers and faces of nine olive hedgerows (6 North–South oriented and 3 East–West). Although sensory attributes were not different, other oil quality parameters may be significantly modified by fruit position. Oils extracted from fruits harvested from higher layers exhibited significantly higher stability against oxidation, along with higher palmitic acid, linoleic acid and phenol contents, but lower oleic acid content. Oils extracted from fruits harvested from East and North facing hedgerows oriented North–South and East–West, respectively, exhibited higher oleic contents and lower saturated and polyunsaturated fatty acid contents. The mean phenol content of oils extracted from fruits from a North–South oriented hedgerow was significantly greater from one of the East–West oriented hedgerows. These findings may be relevant for the design of future olive hedgerows destined for olive oil production.     

CNOOC to Exploit Canada Oil Sand

On April 13,CNOOC(China National Off-shore Oil Corp.)declared that its solely-owned subsidiary CNOOC BelgiumBVBA had signed contract to purchase16.69% shares of Canadian MEG Energy     

“Arbequina” Olive Oil Composition Is Affected by the Application of Regulated Deficit Irrigation during Pit Hardening Stage

Three new regulated deficit irrigation (RDI) treatments were applied to “Arbequina” olive orchards during pit hardening. Oil quality was determined by measuring analytical parameters for olive oil grading, antioxidant activity, total phenol content, fatty acid profile, volatile compounds profile, and sensory analysis. Oils from RDI were classified as “extra virgin olive oil” and their quality was improved due to their higher antioxidant potential (ABTS⁺ [increased ~75%] and DPPH^˙ [increased ~25%] assays) and phenols (increased ~53%) than control. Concentration of total volatile compounds decreased (~27%) but RDI olive oils showed a more balanced profile (alcohols, aldehydes, and esters). Monounsaturated fatty acid content increased (~5%) and atherogenic and thrombogenic indexes decreased (~8.5%) in RDI olive oil. Regarding sensory analysis, RDI provided more balanced oils with higher fruit aroma than control. Other benefits of RDI olive oil, when compared with oil from full irrigated orchards are reduced use of water and improved functional and sensory quality.     

Evaluation of Potential and Real Quality of Virgin Olive Oil from “Campos de Hellín” (Albacete, Spain)

The regulated physicochemical and sensory parameters, stability parameters and fatty acid, sterol and triterpenic dialcohol composition of the olive oils from the varieties Arbequina, Benizal, Cornicabra, Cuquillo, Injerta, Manzanilla de Sevilla, Manzanilla Local, Picual and Negrilla, grown in the Campos de Hellin, were analyzed. Regarding potential quality, all the oil samples were classified in the “extra virgin” category according to the regulated parameters. The oils from the varieties Cornicabra and Picual showed remarkably high stability, due to their high total phenol content. The oils from the Benizal variety stood out due to their high campesterol and low total sterol content, exceeding and not reaching, respectively, the limits set by European regulations. This seems to be an intrinsic characteristic of this variety. When the real quality was analyzed, two clearly differentiated groups were observed: on one hand, oils from the Arbequina variety, and on the other hand, oils from the Picual variety and oils mixed from different varieties (Blend). The great number of olive varieties grown in the Campos de Hellin area enables the production of better balanced oils, producing high quality blended oils since the mixing of different varieties may compensate the deficiencies of monovarietal oils.     

Olive Oil from “Sikitita” under Super-High-Density Planting System in California: Impact of Harvest Time and Crop Season

“Sikitita” is a relatively new olive cultivar obtained from crossbreeding between “Picual” and “Arbequina” that can be trained into the super-high-density orchard system. The impact of harvest time and crop season (2017 and 2018) on fruit parameters, oil quality, and minor compounds was assessed for super-high-density “Sikitita” in California, USA. Maximum olive fruit oil content (~49% on a dry basis) was reached between the first and second weeks of November. Quality parameters were within limits for extra virgin classification for all harvest times during both crop seasons. While total phenols were affected by harvest time, crop year, and their interaction, total volatile content was mainly influenced by harvest time. Both phenolic and volatile compounds reached a maximum concentration by the first week of October, suggesting that harvesting at the beginning of October would lead to a richer oil in terms of minor components. However, oil yield can be maximized if the harvest takes place in November. Our results demonstrated fruit parameters, oil quality, and minor compounds of super-high-density “Sikitita” followed a similar pattern and reached comparable values in both years, despite an earlier maturation in 2018. “Sikitita” has potential as a viable cultivar for growers and processors who are looking to expand on the traditional super-high-density cultivars.     

Characterization of Aroma-Active Compounds in Iranian cv. Mari Olive Oil by Aroma Extract Dilution Analysis and GC–MS-Olfactometry

Aroma, aroma‐active compounds and fatty acid profiles of Iranian olive oil obtained from the cv. Mari were investigated for the first time in the current study. Aroma extracts were isolated from the oil by using a purge and trap extraction system and their compositions were analyzed by gas chromatography‐mass spectrometry‐olfactometry (GC–MS‐O). A total of 35 aroma compounds comprising alcohols, aldehydes, acids, esters, ketones, terpenes and volatile phenols were identified and quantified in the assayed samples. Aldehydes were present at the highest levels, followed by ketones and alcohols. (E)‐2‐Hexenal was quantitatively (1589 µg kg^?1) the main aroma compound in the analyzed oils, followed by hexanal and (E)‐2‐heptenal. The aroma‐active volatiles were elucidated in the aromatic extract by applying aroma extract dilution analysis (AEDA). The results of AEDA revealed 17 aroma‐active compounds. Under these condition it was possible to completely identify 16 of these compounds. Regarding to the flavor dilution (FD) factor, the most potent odorants with the highest FD factor were (E)‐2‐hexenal (512), followed by hexanal, 6‐methyl‐5‐hepten‐2‐one, (E)‐2‐decenal and one unknown compound (LRI = 1871). The fatty acid profile of the tested oils was composed of thirteen compounds. Oleic acid was the main fatty acid (76.01 %) followed by palmitic acid.     

‘Cobrançosa’ Olive Oil and Drupe: Chemical Composition at Two Ripening Stages

The chemical composition and organoleptic characteristics of olive oils may be influenced by genotype and some agronomic factors like olive drupe harvesting date. The aim of this work was to study the influence of olive ripening stage on chemical parameters and the organoleptic profile of fruits and oils of one of the main olive Portuguese cultivars (Cobrançosa). Six different Cobrançosa clones, which were harvested at two different ripening stages in the same olive growing area, were analyzed to evaluate phenolic compounds, ortho-diphenols, flavonoids and antioxidant activity and were characterized in terms of sensorial parameters. These clones have also been classified according to the yield of production. The lowest values in phenolic content, ortho-diphenols, flavonoids and antioxidant activity occurred always in the same clone (110) in both ripening stages in olive fruits and olive oil. This clone has been previously identified as low yield. Also, the results revealed significant correlations between total phenolics and antioxidant activity (R ² = 0.932, P < 0.0001), between ortho-diphenols and antioxidant activity (R ² = 0.9445, P < 0.0001) and between flavonoids and antioxidant activity (R ² = 0.9263, P < 0.0001) on olive oil samples. The sensorial parameters that have been affected in olive oils were herbaceous aroma and flavor, and bitter taste that increased with the ripening process.     

New Shell JV to Seek Jilin Oil Shale

Royal Dutch/Shell signed anagreement on December 9,2004 to set up a joint venture(JV)with the Bureau of Geo-logical Exploration and Min-eral Development of JilinProvince to conduct oil shaleresource studies there.If re-serves prove viable,trial ex-plorations will be launchedand commercial exploitation     

The Effect of Olive Leaf Addition on Antioxidant Content and Antioxidant Activity of “Memecik” Olive Oils at Two Maturity Stages

In this study, the effects of leaf addition, maturity stage and storage on the antioxidant content and activity of olive oils (cv. Memecik) were investigated in the 2008/09 and 2009/10 crop seasons. Olive fruits were harvested at two different maturity stages (early and late), and the leaves of the same cultivar were added at different rates (0, 1, and 3 %) prior to oil extraction. After extraction, the oil samples were stored for 18 months and total chlorophyll, α-tocopherol, total phenolic content and the antioxidant activity [DPPH^· (2,2-diphenyl-1-picrylhydrazyl) and ABTS^·+ (2,2-azino-bis(3-ethylbenzothiazoline)-6-sulfonic acid) radical scavenging] were determined at 6 month-intervals. Olive leaf addition induced a significant increase in total chlorophyll, α-tocopherol, total phenolic content, and antioxidant activities in both years (P < 0.001). During the storage period antioxidant content and antioxidant activities in the oils significantly decreased in both years (P < 0.001). However, the oils to which leaf material was added had higher antioxidant contents and activities than those without leaf material addition at the end of the 18-month storage period. After storage, the antioxidant content and DPPH^· radical scavenging activity of control (0 %) samples were lower than those in the leaf added samples (3 %). The data obtained from this study suggested that the addition of olive leaf to oils allowed more functional olive oils with higher antioxidant contents.