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This paper aims to evaluate effects of the fortification of polyphenolic compound mixtures of quercetin, caffeic acid, tryrosol and hydroxytyrosol in olive oil oxidation.

The authors measured olive oxidation initiated by copper using thiobarbituric acid reactive substance, as an indicator of lipid peroxidation.

Overall, most mixture combinations exhibited oxidation similar to olive oil alone. Some mixture combinations of polyphenolic compounds acted as antioxidants; however, as the concentrations were changed, they became prooxidant in nature.

In vitro studies have limitations for extrapolation to in vivo and clinical studies.

Such information will be useful in determining optimal concentrations and combinations of antioxidants for reducing rancidity and perhaps as models that could be used to modulate various chronic diseases that are associated with oxidative stress.

Olive oil, along with fruits, vegetables and fish, are important constituents of health promoting diets, such as the Mediterranean diet. Active ingredients include monounsaturated fatty acids, oleic acid and a variety of antioxidants including various polyphenolic compounds.

This paper aims to investigate the composition of lubricant and the enhancement of tribological properties using palm oil as a parent base oil mixed with an organo-zinc compound as an additive.

The oil samples were prepared by mixing organo-zinc compound additive, zinc dioctyldithiophosphate (ZnDoDP) and zinc diamyldithiocarbamate (ZDDC), at 0 to 3.0 Wt.% concentrations with commercialised palm oil which were then homogenised using an ultrasonic homogeniser. The oil samples were then tested for their oil properties through elemental analysis, their viscosity index, flashpoint and acid number. Next, the friction test was performed using a four-ball tribometer, and the worn surfaces of the balls were observed using a digital microscope.

The results showed that commercialised palm oil with 2.0 Wt.% of ZnDoDP had excellent characteristics regarding its lubricant properties, such as its viscosity index, coefficient of friction and wear compared to commercialised palm oil with the addition of 2.0 Wt.% of ZDDC.

To the best of the authors’ knowledge, this is the first study to compare the effect of the concentration of ZnDoDP and ZDDC on the lubricant and triological properties of vegetable oil (palm).

AS we have already observed, the road transport undertaking which operates large numbers of vehicles has a very real interest in the quality of the lubricants they use, for this has a direct influence on running costs. This is also true of the older form of public transport, the railway, where in fact the quality of the oils and greases may be even more important.

The purpose of this paper is to propose an initial step for understanding the sensory perception and purchase intent of Brazilian olive oil consumers. It also investigates the sensory perception and purchase intent for a Brazilian-made olive oil.

The sample, consisting of 115 surveyed consumers, is described demographically. The aspects related to sensory analysis and purchase intent associated with the key attributes indicated by the consumers are then discussed. Finally, consumer segmentation is carried out to characterize the consumers in more detail, in terms of both demographic and predictive variables for olive oil consumption.

Consumers displayed a sensory perception that is coherent with olive oil characteristics, thus being able to distinguish three different olive oils from a compound oil sample. Regarding purchase intent and preference, consumers showed mixed behaviors, which was not entirely convergent with the identified sensory aspects. Therefore, it was possible to segment them into three distinct groups: utilitarian, naïve, and expert consumers.

Brazil is an emergent olive oil market, which can create both research and business opportunities for the country. This preliminary study contributes to the advancement of this research subject in the non-traditional markets for olive oil.

UNTIL the introduction of the synthetic rubber‐like materials of various chemical constitutions, the development of qualities to resist oil has been a problem of compounding ordinary rubber with suitable ingredients to give as low a swelling figure in oil as possible. Generally speaking, the more the rubber content could be reduced the greater the resistance of the compound, and the production of really high rubber content oil resisting rubbers was only possible to a limited extent.

This study aims to assess the oxidative stability of avocado oil (AO) at various temperatures, using butylated hydroxytoluene (BHT) as an artificial antioxidant and different concentrations of ultrasonic extract of Chlorella vulgaris.

Extracts of C. vulgaris were obtained using four solvents: water, acetone, ethanol and 80% ethanol-aqueous. Standard techniques were used to conduct qualitative phytochemical screening of the extracts. The extracted samples were analyzed for total phenolics, total flavonoids, antioxidant activity and phenolic compound fractionation. Some physicochemical parameters of AO treated with various concentrations of C. vulgaris ultrasonic extract compared to a 200 ppm BHT and exposed to different temperatures were measured.

The highest phenolic, flavonoids content and antioxidant activity was achieved by 80% ethanolic extract of C. vulgaris . The results showed that exposure of AO to high temperatures led to significant changes in the oil's physicochemical properties. These changes increased as the temperature increased. On the other hand, adding 80% ethanolic extract of C. vulgaris into AO reduced the effect of heat treatment on the change in physicochemical properties.

Adding 80% ethanolic extract of C. vulgaris into AO can potentially reduce the impact of heat treatment on the alteration of physicochemical properties.

The purpose of this study is to compare the oxidative stability of non‐hydrogenated cottonseed oil with that of the partially hydrogenated oils commonly used as a deep‐fat frying medium by the restaurant industry when used to prepare French fries in order to reduce trans‐fatty acids.

Stability characteristics of non‐hydrogenated cottonseed oil and two hydrogenated oils, canola and soybean, were evaluated in deep‐fat frying applications. French fries were analyzed for total polar compounds, and the oils were analyzed for iodine, peroxide, p‐anisidine and totox values, and free fatty acids.

Canola and soybean oil had significantly lower iodine values than cottonseed oil. Free fatty acid values were not significantly different among the oils (0.256 per cent oleic acid). Initially cottonseed oil had higher peroxide, p‐anisidine, and totox values compared with canola and soybean oil. However, as days of frying increased, values trended closer together. Total polar compounds were similar. All oil types were comparable in terms of their stability characteristics under the conditions used in this study.

Research with additional food product and under more stressful conditions would be beneficial.

Hydrogenation increases trans‐fatty acid content. Consumption of trans‐fatty acids has been associated with increased risk of heart disease. Non‐hydrogenated cottonseed oil may be a viable alternative to popular hydrogenated oils currently used in the restaurant setting.

Restaurants are being pressured by health officials to choose healthier oil. This research article can help restaurants make an informed choice.

The aim of this study was to investigate the antibacterial activity of original extra virgin olive oil in Iran on some food borne pathogens.

Microbial analysis tests including disk diffusion and detections of minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were used. Also the chemical composition analysis of the oil was determined by GC-MS. Results of disk diffusion test confirmed antimicrobial activity for the oil in which S.aureus and E. coli were more resistant than L. innocua.

The MIC and MBC of organic extra virgin olive oil on the studied pathogens were in the range of 12.5-25 and 100 per cent v/v, respectively. The GC-MS analysis showed Z-9-Octadecenal (32.75 per cent), Oleic acid (15.78 per cent), Squalene (11.856 per cent), Phenol (8.392 per cent), Palmitic acid (1.884 per cent) as the main compounds (>0.7 per cent) in organic extra virgin olive oil, which have functional role in the biological activities.

This is the first study on organic extra virgin olive oil from Iran. According to the results, extra virgin olive oil has antimicrobial activity on foodborne pathogens.

OF the whole range of metal rolling operations, almost the only section in which rolling oils are normally employed is in the cold rolling of flat material in plain cylindrical rolls. The metal for cold rolling has usually first been hot rolled in plain cylindrical rolls, but only in a few cases are rolling oils used in the hot rolling operation. These exceptions are referred to when considering the particular metals.

Previous work has suggested that the adhesion between oil and metallic surfaces of an engine could be an important factor in determining crankcase cleanliness. It can be shown that it is only necessary to measure the spreading pressure of an oil on metal in order to get a direct measure of the work of adhesion, Surface tensions of lubrictaing oils vary very little and it can be assumed that the critical film pressure (C.F.P.) obtained with a given apparatus is an acceptable measure of the work of adhesion as well as of the spreading pressure. Oils of similar properties may vary tenfold in their C.F.P's. The addition of additives influences the spreading pressure, the largest increments in C.F.P. being given by dispersant and detergent additives.