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Oil Type (oil + type)
Selected AbstractsRetention and Distribution of Polyphenols after Pan-Frying of French Fries in Oils Enriched with Olive Leaf ExtractJOURNAL OF FOOD SCIENCE, Issue 8 2007A. Chiou ABSTRACT:,Palm oil, olive oil, and sunflower oil were supplemented with an extract rich in polyphenols obtained from olive tree (Olea europaea) leaves at levels of 120 and 240 mg total polyphenols per kilogram of oil. Pan-frying of potatoes was performed in both the enriched and the nonsupplemented oils under domestic frying conditions. Total polyphenol content was estimated by the Folin,Ciocalteau assay, oleuropein was determined by HPLC analysis, while other individual polyphenols by GC/MS analysis. Fourteen polyphenol species were identified in the olive leaf extract, among which oleuropein predominated (1.25 g/kg olive leaves). All the enriched oils contained oleuropein before and after frying. Oleuropein as well as other polyphenol species were detected in all French fries cooked in enriched oils. Polyphenol intake by consuming French fries pan-fried in the enriched oils was calculated to be 6 to 31 times higher than that in the case of French fries fried in commercial oils, being dependent on the frying oil type. [source] Evaluation of the Self-Heating Tendency of Vegetable Oils by Differential Scanning CalorimetryJOURNAL OF FORENSIC SCIENCES, Issue 6 2008Amélie Baylon M.S. Abstract:, The evaluation of the self-heating propensity of a vegetable (or animal) oil may be of significant importance during the investigation of a fire. Unfortunately, iodine value and gas chromatographic-mass spectrometric analysis do not lead to meaningful results in this regard. To the contrary, differential scanning calorimetry (DSC), which does not measure the chemical composition of the oil, but rather its thermodynamic behavior, produces valuable results. After a thorough literature review on the autooxidation of vegetable oils, several oils with different self-heating tendencies were analyzed using a Mettler-Toledo differential scanning calorimeter DSC 25 between 40°C and 500°C. Analyses were carried out both under air and nitrogen atmosphere to identify the phenomena due to autooxidation reactions. Using DSC, it was possible to observe the induction period of the oil (when available), the three different exothermic events, and the autoignition temperature (relatively independent of the oil type). [source] PETROLEUM SEEPAGES AT ASUK, DISKO, WEST GREENLAND: IMPLICATIONS FOR REGIONAL PETROLEUM EXPLORATIONJOURNAL OF PETROLEUM GEOLOGY, Issue 3 2007J. A. Bojesen-Koefoed Organic geochemical screening and biological marker analysis was carried out on a total of 45 Albian-Cenomanian sandstone and mudstone samples collected from a landslide block on thenorth coast of Disko island, central West Greenland. The landslide block covers an area of severalsquare kilometres, and originated approximately 400 m up-section from where it moved to itspresent position after the last glaciation. The mudstones are generally rich in organic carbon butshow no potential for petroleum generation. However, biodegraded oil stains were found in thepoorly lithified sandstones. Staining by undegraded or only slightly degraded oil in volcanic rocks iscommon in this region, but the occurrence described here is the only known outcrop where staining occurs in siliciclastic sediments, and also the only one known in which the oil is severely biodegraded. The oil stains appear to represent a biodegraded variety of the Cretaceous marine shale derived Itilli oil type which is known from many locations in the Disko-Nussusaq-Svartenhuk Halvø region. The oils entered the sandstones before the landslide event, probably during or beforethe extrusion of the volcanic succession in the Paleogene. This is the first time that a petroleum seepage has been found to the east of the Kuugannguaq-Qunnillik fault zone, which is located approximately 30 km west of Asuk. The presence of stainingby marine oil at Asuk demonstrates that marine petroleum source rocks were deposited muchfurther eastwards than was previously thought, thus expanding the area of potential explorationsignificantly. The presence of marine source rocks to the east of the Kuugannguaq-Qunnillik faultzone may explain the frequent observation of Direct Hydrocarbon Indicators in seismic datacollected in the Vaigat Sound. [source] A review of the background, operating parameters and applications of microemulsion liquid chromatography (MELC)JOURNAL OF SEPARATION SCIENCE, JSS, Issue 15 2005A. Marsh Abstract Microemulsions are dispersions of nanometre-sized droplets of an immiscible liquid within another liquid. Droplet formation is facilitated by the addition of surfactants and often also cosurfactants. Microemulsions are classified as either oil-in-water (O/W) (oil droplets such as octane dispersed throughout aqueous buffer) or water-in-oil (W/O) (aqueous droplets in oil such as hexane). Both microemulsion types have been used as mobile phases for separation in microemulsion HPLC (MELC). There has been a recent increase of interest in this area with new applications and developments such as gradient elution and optimisation of methods using experimental design. O/W microemulsions have been employed as eluents for RP-HPLC while W/O microemulsions have been used for normal phase chromatography. Separations can have superior speed and efficiency to conventional HPLC modes while offering a unique selectivity with excellent resolution. The capability for quantitative and stability-indicating analysis has also been demonstrated. Specific advantages include the ability to operate at low UV wavelengths and elimination of the need for an equilibration rinse between gradients. Operational issues associated with the use of MELC have been identified including the need to add salt to the gradient eluent, relatively high back-pressures and increased need for equipment cleaning compared to conventional RP eluent. This report details the different microemulsion types and compositions used and their reported applications. The use of gradient and isocratic elution is described. The effects on separations of varying operating parameters such as temperature, oil type and concentration, surfactant type and concentration, sample solvent, column type, and organic solvent addition will be discussed and illustrated. [source] The influence of oil type and frying temperatures on the texture and oil content of French friesJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 15 2005Agnieszka Kita Abstract The purpose of the present study was to determine the effects of the frying medium and temperatures on fat content and texture of French fries. The material taken for the study consisted of seven types of vegetable oil: refined sunflower, rape, soy, olive oil, palm, partially hydrogenated rape oil (modified oil I) and a blend of vegetable oils (modified oil II). The French fries prepared from Asterix potato variety were fried at oils heated to 150, 160, 170, 180 and 190 °C. The length of frying (12, 10, 8, 6.5 and 4.5 min, respectively) depended on oil temperature. Fat content and the texture of French fries were determined. The type of frying medium significantly affects the texture of French fries. Temperature influenced both the fat content and texture of product. The increase of frying temperature decreased fat uptake and hardness of French fries. French fries fried in rape oil exhibited the most delicate texture and the lowest oil absorption when compared with French fries fried in other types of oil under investigation. Copyright © 2005 Society of Chemical Industry [source] Influence of oil type on the performance characteristics of a two-axial groove journal bearingLUBRICATION SCIENCE, Issue 9 2009D. M. C. McCarthy Abstract The use of environmentally adapted lubricants (EALs) is a subject of growing interest to industry as legislation increasingly demands the replacement of mineral oil lubricants. Vegetable-based fluids are widely seen as providing lubricants from a renewable source, as well as meeting demands for improved biodegradability. However, at present, utilization of such fluids is limited due to their rapid oxidation. EALs produced from other base stocks (i.e. synthetic esters) have been shown to provide performance benefits in hydrodynamic thrust bearings. In the present study, a hydrodynamic journal bearing test rig has been employed to compare the performance of three EALs (a VG32 saturated ester, rapeseed base fluid and a propylene glycol dioleate) relative to three mineral turbine oils (ISOVG32, ISOVG46 and ISOVG68) in the hydrodynamic regime. Results are given in terms of temperature, power loss and minimum film thickness. The impact of oil viscosity index is also discussed. Copyright © 2009 John Wiley & Sons, Ltd. [source] Evaluation of canola oils as alternative lipid resources in diets for juvenile red seabream, Pagrus auratusAQUACULTURE NUTRITION, Issue 5 2003B. Glencross Abstract This study examined three potential oil resources, crude and refined canola oil and refined soybean oil as replacements for added dietary fish oil in diets for juvenile red seabream. These oil resources were evaluated for their potential to replace added fish oil (40 g kg,1) in fishmeal based (600 g kg,1) diets, with 100 g kg,1 of total lipids. Each of the three plant oils was used to replace 25%, 50%, 75% or 100% of the added dietary fish oil. Each of the three plant oils showed potential as a replacement for dietary fish oil, although a significant reduction in growth and feed utilisation was observed with the complete (100%) replacement of added fish oil by crude canola oil. No other significant effects of oil type or inclusion level on growth were apparent. A negative control (no added fish oil or plant oil, 60 g kg,1 of total lipid) yielded poorer growth than all treatments except the diet containing 40 g kg,1 of added crude canola oil (100% replacement). This observation confirmed that the added oils were utilized by the fish. A positive control diet containing 80 g kg,1 of added fish oil (140 g kg,1 total dietary lipid) sustained the best growth in the study, confirming that the 13 experimental diets were energy limiting as planned. Notably, few effects of the alternative oils were seen on the proximate composition of the fish. However, the influence of the alternative oils on the tissue fatty acid composition was considerable, irrespective of plant oil type or processing grade. Particularly notable was the overall increase in the level of polyunsaturated fatty acids in the tissues of the fish fed the plant oil diets, with these trends becoming more apparent with the greater levels of fish oil replacement. Minimal reductions in the levels of the long-chain polyunsaturated fatty acids of eicosapentaenoic (20:5n-3) and docosahexaenoic (22:6n-3) acid were observed from any of the plant oil treatments. Sensory assessment, by an Australian taste panel, of the fish fed the fish oil reference, or the 100% replacement by refined canola or refined soybean diets showed a preference in order of canola oil > soybean oil > fish oil fed fish. Clearly, both canola and soybean oils have considerable potential as replacements of fish oils in diets for this species. [source] Potato Chip Quality and Frying Oil Stability of High Oleic Acid Soybean OilJOURNAL OF FOOD SCIENCE, Issue 6 2005Kathleen Warner ABSTRACT High oleic soybean (HOSBO) and low linolenic acid soybean (LLSBO) oils were evaluated individually and in a 1:1 blend along with cottonseed oil (CSO) to determine frying oil stabilities and the flavor quality and stability of potato chips. Potato chips were fried in the oils for a total of 25 h. Potato chips and oils were sampled periodically for sensory data, gas chromatographic volatile compounds, free fatty acids, and total polar compounds. Total polar compounds levels decreased with increasing amounts of oleic acid. The LLSBO had the highest overall increase (17.3%) in total polar compounds from 0 to 25 h of frying. Flavor evaluations of fresh and aged (0, 1, 3, 5, and 7 wk at 25 °C) potato chips showed differences between potato chips fried in different oil types. Potato chips fried in either LLSBO or in the 1:1 blend had significantly higher intensities of deep fried flavor than the chips fried in HOSBO. Potato chips fried in HOSBO, which had 2% linolenic acid and 1.3% linoleic acid, had significantly higher fishy flavor intensity than chips fried in the other oils. The presence of linoleic acid at a level lower than the amount of linolenic acid probably allowed for the fishy flavors from the degradation of linolenic acid in HOSBO to become more apparent than if the linoleic acid level was higher than linolenic acid. Hexanal was significantly higher in potato chips fried in LLSBO than in the chips fried in the other oils, indicating low oxidative stability during storage. Blending HOSBO with LLSBO in a 1:1 ratio not only improved flavor quality of chips compared with those fried in HOSBO, but also improved oil fry life and oxidative stability of chips compared with LLSBO. [source] Carotenoid Content and Physicochemical and Sensory Characteristics of Carrot Chips Deep-Fried in Different Oils at Several TemperaturesJOURNAL OF FOOD SCIENCE, Issue 9 2001A. Sulaeman ABSTRACT: The influence of deep-frying using different oils and temperatures on carotenoid content and physicochemical and sensory characteristics of carrot chips was investigated. Sliced carrots were steam-blanched, cooled, soaked in 0.2% sodium metabisulfite, and deep-fried in canola, palm, or partially hydrogenated soybean oil (PHSO) at 165, 175, or 185 °C. Frying temperature, but not oil, significantly (P < 0.05) affected the ,-carotene, ,-carotene, and total carotenoid contents. Oil type significantly (P < 0.05) influenced all color values. Increasing temperature lowered the redness value, which correlated with decreased carotenoid content, color darkening, and decreased hardness value. Trained panelists detected no differences among oil types in crispness, sweetness, odor, and acceptability. The best carrot-chip product was that fried in PHSO at 165 °C. [source] A method of measuring oil consumption by labelling with radioactive bromineLUBRICATION SCIENCE, Issue 3 2000H. Zellbeck Abstract A method of determining the oil consumption rate of combustion engines is presented. It is based on labelling the individual oil fractions of engine oil with radioactive bromine isotope82 Br and on the quantitative absorption of radioactive bromine compounds in the exhaust gas in an aqueous solution of nitric acid and silver nitrate. The advantages of this method are that the oil that is consumed in the exhaust gas can be directly measured, without the fluctuating amounts of oil in the sump influencing the result, and the behaviour of the individual components of the oil in the consumption process can be determined. The test is quick, only twenty minutes being required to detect oil consumption at one operating point; and with a single labelling, the oil consumption at a great number of working engine points can be measured 82 Br has a short half-life of only 36 h, so that compliance with radiation protection measures is inexpensive and investigations can be carried out using a conventional testing device. As part of the research project, a study was made of the influence of different base oil types, with and without polymer additives, on consumption. Results showed that Noack evaporation loss correlated with oil consumption only with boiling fractions of exactly the same base oil, and not with different, in particular synthetic, base oils; that polymer additives (VI improvers) significantly reduced the rate of oil consumption; and that the polymer additive and the type of base oil both had more influence on oil consumption than viscosity. [source] | |||||||||||||