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Vegetable Oils (vegetable + oil)
Selected AbstractsDETERMINATION OF BENZO(a)PYRENE IN VEGETABLE OILS BY HIGH PERFORMANCE LIQUID CHROMATOGRAPHYJOURNAL OF FOOD QUALITY, Issue 3 2007EKERO, LU GÜLTEN ABSTRACT Analysis of 40 oil samples showed that 38 of them were contaminated with benzo(a)pyrene (BaP). Thirty of the 38 BaP-contaminated edible oil samples did not have any label of a brand name. BaP content for the 38 contaminated edible oil samples were in the range of 1.22,74.89 ppb. Sixteen of the contaminated oil samples had BaP content of more than 10 ppb, which is the maximum tolerable limit for the Turkish Food Codex Regulation. BaP contents of samples for each type of oil were significantly different (P < 0.05) from each other. [source] Book Review: Vegetable Oils in Food Technology by Frank D. GunstoneEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 6 2003Sylvain Claude No abstract is available for this article. [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] Zanthoxylum piperitum (DC), a potential feeding deterrent for mammals: studies with Microtus ochrogaster (Wagner)PEST MANAGEMENT SCIENCE (FORMERLY: PESTICIDE SCIENCE), Issue 7 2004Gisela Epple Abstract Total extract from the fruit of Szechuan pepper (Zanthoxylum piperitum DC), the volatile components of the extract and a non-volatile fraction containing alkylamides (NVA fraction) are feeding deterrents for rats. The present study investigated the effectiveness of these natural repellents in prairie voles (Microtus ochrogaster Wagner). Two-choice feeding trials were conducted during which food-deprived voles were offered choices between oat-bran wafers. In Experiment 1, 10 voles were given three sets of feeding trials, each 2 h long. Baseline consumption was established during the first set of two trials by offering a choice between two oat-bran wafers dipped in ethanol, the control solvent. During the second set of two trials the voles were given a choice between an oat-bran wafer dipped in ethanol and a wafer dipped in Zanthoxylum extract. During the third set the voles were given a choice between a wafer served on top of a screened dish containing a sample of ethanol and a wafer served on top of a dish containing a sample of extract. In this manner the voles were exposed to volatile compounds emanating from the extract but could not contact it. Wafers dipped in extract were almost completely avoided. The volatile components of extract also significantly reduced food intake. In Experiment 2, habituation to the volatile constituents of extract was examined in 16 Zanthoxylum -naïve voles. Baseline consumption was established by offering two wafers served on top of screened dishes containing ethanol. This was followed by twelve tests during which a choice between a wafer served above a sample of ethanol and a wafer served above a sample of extract was given. The voles failed to habituate to the volatile components of extract, consistently consuming less of the wafers served above extract. In Experiment 3 a dose-response curve to Zanthoxylum extract was established, using 12 stimulus-naïve voles. After baseline consumption was established, the animals were given two tests each, presenting a choice between a control wafer and a wafer dipped in a dilution of extract (0.001,100 g liter,1). Only concentrations of 10 and 100 g liter,1 reduced food intake. In Experiment 4 the effects of the non-volatile fraction of extract were compared to those of whole extract. Vegetable oil was used as solvent. Eight stimulus-naïve voles were given two tests with a choice between an oil-dipped and an extract-dipped wafer. A second group of eight voles received two tests with a choice between an oil-dipped and NVA-dipped wafer. Extract-dipped wafers were avoided, but the NVA fraction had no effect on food consumption. Copyright © 2004 Society of Chemical Industry [source] Tocotrienols and cancer: Beyond antioxidant activityEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2007Kalanithi Nesaretnam Abstract The edible oil industry has emerged as an important provider of raw material for the extraction of vitamin,E. Vegetable oils, especially the seed oils, are rich sources of tocopherols. However, in palm oil, vitamin,E occurs as a complex mixture of tocopherols and tocotrienols. Various tocotrienol isomers of vitamin,E in palm oil have been reported to possess interesting biological and physiological properties not generally evident with tocopherol-rich vitamin,E preparations. They include potential blood cholesterol-lowering and cardioprotective effects, more efficient antioxidant activity in biological systems, and possible anti-cancer and neuroprotective effects. With the emergence of palm oil as the largest edible oil in world markets, technology is now available to extract tocotrienol-rich palm vitamin,E. Initiatives in Malaysia to manufacture biodiesel will further generate large amounts of micronutrients, especially tocotrienols, to be available to the nutraceutical and functional food industry. [source] Influence of fatty acid additives on the tribological performance of sunflower oilLUBRICATION SCIENCE, Issue 9 2010Patrick Baumgart Abstract Vegetable oils are potential substitutes for petroleum-based lubricants because they are environmentally friendly, renewable, less toxic and readily biodegradable. The addition of free fatty acids has been shown to increase the lubrication performance of vegetable oils at elevated temperatures. The purpose of this study was to evaluate the relationship between the length of the carbon chain in the fatty acid and its effectiveness as an additive for a range of elevated temperatures. Stearic, arachidic and behenic fatty acid additives were added to commercial sunflower oil. All fatty acid additives were shown to be effective in lowering the wear rate and coefficient of friction in ball-on-disc tribological tests. The overall carbon chain length was not observed to have a consistent influence on the effectiveness of the additive. All additives were less effective at temperatures above 100°C. Copyright © 2010 John Wiley & Sons, Ltd. [source] Predicting world health organization toxic equivalency factor dioxin and dioxin-like polychlorinated biphenyl levels in farmed atlantic salmon (Salmo salar) based on known levels in feedENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 1 2007Marc H. G. Berntssen Abstract Assimilation and elimination rate constant of dietary polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DLPCBs) with a World Health Organization toxic equivalency factor (WHO-TEF) were estimated in market-size Atlantic salmon (Salmo salar) using fish that were previously fed vegetable oil,based (low in PCDD/Fs and DLPCBs) or fish oil,based (high in PCDD/Fs and PCBs) diets. At the start of the kinetic trial, half the fish that were fed fish oils were fed vegetable oil feeds and inverted (cross-over design) for five months. The assimilation efficiencies of the PCDD/F congeners were more variable (3,89%) and, generally, were lower than those of the DLPCBs (70,80%). Among the PCDD/F congeners, the assimilation efficiency of the most toxic tetra- and pentachlorinated PCDD/Fs was greater than that of higher-chlorinated PCDD/Fs. Elimination rates for DLPCBs were higher than those for PCDD/Fs. Lower-chlorinated PCDDs had a lower elimination rate than the higher-chlorinated PCDDs, but no differences were observed among PCDF congeners or DLPCB congeners. Kinetic parameters were used to predict the level of WHO-TEF dioxins and DLPCBs in Atlantic salmon reared in a large-scale facility under commercial conditions. Predictions were based on preanalyzed levels of these organochlorines in feeds with three different replacement levels (0, 30, and 60%) of vegetable oil. A simple one-compartmental, first-order kinetic model was used to predict the level of sum WHO toxic equivalents for PCDD/Fs and DL-PCBs. The predicted values varied by 0 to 11% from the measured values in the commercially reared salmon. [source] Effects of additives on oxidation characteristics of palm oil-based trimethylolpropane ester in hydraulics applicationsEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2009Nor Halaliza Alias Abstract Hydraulic fluids represent one of the most important groups of industrial lubricants. Increasing attention to environmental issues drives the lubricant industry to choose vegetable-based hydraulic fluids which are biodegradable as compared to mineral-based fluids. However, the lubricating properties of vegetable oil, such as poor oxidative stability and high pour point, have hindered their use. In this study, trimethylolpropane ester, which was derived from palm-based methyl ester, was used as the base hydraulic fluid. The purpose of the study was to determine the optimum formulation for palm oil-based synthetic lubricants by using suitable additives that can improve the oxidative stability and viscosity in accordance with the standard regulations for hydraulic fluid applications. The oxidative stability of the oil was evaluated by total acid number (TAN) and viscosity tests. In general, base oil without additive began to degrade after 200,h. The formulated oil, on the other hand, was quite stable even after 800,h of operation. The best formulation was obtained using 1.0% of either additive,A or additive,B. Both TAN and viscosity values were found to increase with increasing heating temperature. Meanwhile, the results have also shown that additive,A performs better than additive,B. After 800,h of exposure, the final TAN value for the formulated oil was only at 0.32 as compared to 4.88,mg KOH/g for the oil without additive. However, the kinematic viscosity of the oil at 40 and 100,°C was almost unchanged as compared to the oil without additive. [source] A simplified method for HPLC-MS analysis of sterols in vegetable oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 12 2008Antonio Segura Carretero Abstract We have developed a liquid-chromatographic method using atmospheric pressure chemical ionization (APCI)-mass spectrometry (MS) detection in positive mode. This method was used to separate and identify 15,sterols and 2,dihydroxy triterpenes in saponified oils, enabling the analysis of these compounds directly from saponified samples without recourse to thin-layer chromatography; this fact thus significantly simplifies the process. The analyses were made using a Waters Atlantis 5,µm dC18 150×2.1,mm column with a gradient of acetonitrile/water (0.01% acetic acid) at a flow rate of 0.5,mL/min and a column temperature of 30,°C. The quantification of several of these compounds in soybean oil, palm oil, seed oil, sunflower oil, olive-pomace oil and virgin olive oil was carried out using their commercial standards, and the results were compared satisfactorily with the official method. [source] Simplification of separation of the reaction mixture after transesterification of vegetable oilEUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 4 2008Martin Hájek Abstract A heterogeneous reaction mixture is formed by transesterification of vegetable oils. The reaction mixture contains mainly methyl esters of higher fatty acids and glycerol. From this mixture, biodiesel is gained by spontaneous sedimentation in the gravitational field. The sedimentation can be considerably accelerated by controlled addition of water. It was found that addition of small amounts of water to the crude reaction mixture significantly affected the mixture, and substantial changes in the speed of the separation took place. Considerable differences in the composition and quality of the ester and glycerol phases occurred. The optical properties (transmittance and refractive indices) of the heterogeneous reaction mixture are changed after addition of water; this change can be observed spectrophotometrically. This method is applicable to all types of vegetable oils including waste frying oils. [source] The level of polyaromatic hydrocarbons in kajal and surma of major Indian brandsINTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 3 2009D. K. Patel Synopsis Kajal and surma are eye cosmetics extensively used in Indian subcontinent. Kajal is prepared by burning of vegetable oil and butter oil while surma by grinding of the stones. High performance liquid chromatography and gas chromatography,mass spectrometry instruments were used for quantification and confirmation of 16 polyaromatic hydrocarbons (PAHs). Significant concentration of PAH was found in all the samples examined. The median concentration of PAH ranged from 0.14 (lowest, anthracene) to 31.18 ,g g,1 [dibenz(a,h)anthracene] in kajal sample and from not detectable concentration (naphthalene) to 197.47 ,g g,1 of benzo(a)pyrene in surma sample. Fifteen PAHs were detected in all the samples. Therefore the use of kajal and surma in eye should be strictly restricted. Résumé Le Kajal et le Surma sont des composés très utilisés sur le sous-continent indien pour le maquillage des yeux. Ils sont préparés par calcination d'huile végétale et d'huile de beurre, puis par broyage des résidus. La chromatographie liquide haute pression et la chromatographie en phase gazeuse couplée à la spectrométrie de masse ont été employées pour quantifier et valider seize hydrocarbures polyaromatiques (PAHs). Des concentrations significatives en PAHs ont été trouvées dans les échantillons examinés. La concentration médiane en PAH classées de la faible à la plus élevée est de 0,14 ,g g,1 (anthracène) à 31,18 ,g g,1 (dibenz (a,h) anthracène) dans l'échantillon de Kajal et d'une présence ND (naphtalène) à 197,47 ,g g,1 (benzo (a) pyrène) dans l'échantillon de Surma. Quinze PAHs ont été détectés dans tous les échantillons. En conséquence, l'utilisation de Kajal et de Surma pour la cosmétique des yeux doit être limitée de façon stricte. [source] The effects of ingredients on popcorn popping characteristicsINTERNATIONAL JOURNAL OF FOOD SCIENCE & TECHNOLOGY, Issue 4 2004Mehmet Ceylan Summary Response surface methodology was used to evaluate the effects of ingredients on popcorn popping characteristics. The effects of different ingredients on the expansion volume and unpopped kernel ratio of popcorn in a conventional popper and a microwave oven were evaluated and optimized by response surface methodology. The regression models were significant and had R2 value in the range of 0.919,0.956. The optimum levels of ingredients for microwave popping were 4.4% salt, 5.9% vegetable oil, 0% sodium bicarbonate and 16.4% butter, this formulation giving an expansion volume of 33.1 mL g,1. In the case of conventional popping, the maximum expansion volume of 37.3 mL g,1 was obtained for 3.5% salt, 6% vegetable oil, 0.10% sodium bicarbonate and 12.9% butter. [source] Inhibition of elastase activity by essential oils in vitroJOURNAL OF COSMETIC DERMATOLOGY, Issue 4 2002Masahiro Mori Summary, Background, Essential oils are widely used, for example in aromatherapy and aroma massage. In aroma massage, essential oil, diluted with vegetable oil, is rubbed onto the skin. Components of essential oil penetrate into the skin and have an influence on the dermis. Elastase is an enzyme which degenerates dermal elastin. Elastase activity is believed to contribute to cutaneous wrinkling and ageing. Aim, To investigate the inhibitory effect of essential oils on elastase activity. Methods, Inhibition of elastase activity by various essential oils was assessed using two elastase enzymes: porcine pancreatic elastase (PPE) and human neutrophil elastase (HNE). Results, Elastase activity was inhibited by various essential oils, especially by those oils derived from lemons, juniper and grapefruit. Although the specific inhibitory component was not determined, lemon oil had the greatest inhibitory effect on PPE. Some essential oils also inhibited HNE. Conclusions, These studies demonstrate a possible rationale for the use of essential oil massage as a preventive treatment for cutaneous wrinkling and ageing. [source] ,-Oxidation capacity in liver increases during parr-smolt transformation of Atlantic salmon fed vegetable oil and fish oilJOURNAL OF FISH BIOLOGY, Issue 2 2006I. Stubhaug Atlantic salmon Salmo salar were fed diets containing 100% fish oil (FO; capelin oil) or 100% vegetable oil (VO) from start of feeding until the fish reached the size of 2·5 kg. Samples were taken during the period of the parr-smolt transformation (October 2002 to February 2003). The VO diet consisted of a blend of 55% rapeseed oil, 30% palm oil and 15% linseed oil to maintain the sum of saturated, monounsaturated and polyunsaturated fatty acids between the two diets, although with differences in the individual chain length of fatty acids. Na+/K+ -ATPase activity in the gills, total ,-oxidation capacity in muscles and liver and total lipid, glycogen and dry matter content in the muscles were measured during the parr-smolt transformation and after seawater transfer. Na+/K+ -ATPase activity in gills increased prior to seawater transfer, showing an adaptation for seawater survival. Major changes in the lipid and glycogen content in the fillet and in ,-oxidation capacity were found in the tissues measured. ,-oxidation capacity increased significantly in liver and decreased in red muscle, prior to seawater transfer, giving liver an important role in energy production during this period. Results also indicated that feeding Atlantic salmon a diet where 100% of FO was replaced with VO did not have any negative effects on lipid metabolism during parr-smolt transformation. [source] The effects of rising food prices on poverty in MexicoAGRICULTURAL ECONOMICS, Issue 2008Jorge N. Valero-Gil Food price changes; Poverty; Mexico Abstract We evaluate the impact of the rise in food prices during 2006,2008 on the poverty and extreme poverty rates in Mexico. We concentrate on the poor's consumption of staple foods, and analyze the change in their consumption brought about by changed prices. We also allow households receiving income from the farming and livestock sector to benefit from increases in prices of food products. We find a modest increase in poverty using 2006,2007 prices; however, there is a daunting effect on the poor once the 2008 prices are taken into account. After considering the positive effects of public policies announced in 2008, such as reduced taxes and tariffs on food products and greater subsidies to the extremely poor, the poverty rate measured through consumption increases from 25% to 33.5%, and the extreme poverty rate from 10.58% to 15.95%, given the increase in food prices. Further analysis using the theory of optimal taxes suggests policies oriented towards relieving the food price pressure on the Mexican poor should aim at lowering the prices of eggs, vegetable oil, milk, and chicken. [source] Preparation and characterization of monodisperse superparamagnetic poly(vinyl alcohol) beads by reverse spray suspension crosslinkingJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 1 2008Chengli Yang Abstract A novel protocol for preparing magnetic poly(vinyl alcohol) (PVA) beads by reverse spray suspension crosslinking was reported. The hydrophilic Fe3O4 nanoparticles were mixed with PVA, glutaraldehyde, and water to form aqueous phase. Then the aqueous phase was sprayed into vegetable oil by a pressure of nitrogen gas to form water in oil (W/O) suspension. The magnetic PVA beads were obtained in the presence of hydrochloric acid catalyst. It was found that the magnetic PVA beads obtained good properties when the PVA concentration was 10%, and the oil phase temperature was controlled at 40 °C. The mechanical stirring has little impact on the size of magnetic PVA beads in the process of reverse spray suspension crosslinking. The Cibacron Blue (CB) was coupled on the surface of magnetic PVA beads by surface chemical reaction. The morphology, size, and magnetic properties of the magnetic PVA beads were examined by scanning electron microscopy, laser diffraction, and vibrating sample magnetometer, respectively. Compared with the stirring method, it was found that the size of magnetic PVA beads was monodisperse and their saturation magnetization was much higher. Fourier transform infrared and X-ray photoelectron spectroscopy experimental results proved that CB molecules were covalently immobilized onto the surface of the magnetic PVA beads. Meanwhile, the protein affinity separation experiments demonstrated that the magnetic PVA beads can potentially be used as a carrier for large-scale protein separation. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 203,210, 2008 [source] A critical review of methodologies used in determination of relative bio-availability ratio of RRR -,-tocopheryl acetate and all - rac -,-tocopheryl acetateJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 10 2010Yueming Dersjant-Li Abstract Bio-availability of different ,-tocopherol forms in livestock animals is measured by the increase in plasma or tissue concentrations of ,-tocopherol after oral administration. It is generally accepted that RRR -,-tocopheryl acetate (natural source vitamin E derived from vegetable oil) has a higher bio-availability compared to all - rac -,-tocopheryl acetate (synthetic vitamin E, i.e. ,-tocopherol produced by chemical synthesis). However, different bio-availability ratios have been reported in the literature. The major reason for conflicting results in literature studies was the inability to separate the proportion of ,-tocopherol originating from test materials, from the proportion of ,-tocopherol originating from basal dietary ingredients and pre-feeding. This causes significant variability. For bio-availability determination, a baseline or control treatment is essential. The estimation of bio-availability without correction for basal vitamin E status will lead to incorrect interpretation of the results. When using proper methodologies, it is possible to correct for the impact of ,-tocopherol intake from basal ingredients and ,-tocopherol originating from pre-feeding, therefore yielding results reflecting the true relative bio-availability of different ,-tocopherol substances. When reviewing literature data a critical evaluation of the method used in determination of relative bio-availability is recommended. Copyright © 2010 Society of Chemical Industry [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] Micromorphology of resin,dentin interfaces using one-bottle etch&rinse and self-etching adhesive systems on laser-treated dentin surfaces: A confocal laser scanning microscope analysisLASERS IN SURGERY AND MEDICINE, Issue 7 2010Marcelo Tavares de Oliveira DDS Abstract Background and Objectives This study evaluated the hybrid layer (HL) morphology created by three adhesive systems (AS) on dentin surfaces treated with Er:YAG laser using two irradiation parameters. Study Design Occlusal flat dentin surfaces of 36 human third molars were assigned into nine groups (n,=,4) according to the following ASs: one bottle etch&rinse Single Bond Plus (3M ESPE), two-step Clearfil Protect Bond (Kuraray), and all-in-one S3 Bond (Kuraray) self-etching, which were labeled with rhodamine B or fluorescein isothiocyanate,dextran and were applied to dentin surfaces that were irradiated with Er:YAG laser at either 120 (38.7,J/cm2) or 200,mJ/pulse (64.5,J/cm2), or were applied to untreated dentin surfaces (control group). The ASs were light-activated following MI and the bonded surfaces were restored with resin composite Z250 (3M ESPE). After 24,hours of storage in vegetable oil, the restored teeth were vertically, serially sectioned into 1-mm thick slabs, which had the adhesive interfaces analyzed with confocal laser microscope (CLSM,LSM 510 Meta). CLSM images were recorded in the fluorescent mode from three different regions along each bonded interface. Results Non-uniform HL was created on laser-irradiated dentin surfaces regardless of laser irradiation protocol for all AS, while regular and uniform HL was observed in the control groups. "Stretch mark"-like red lines were found within the HL as a result of resin infiltration into dentin microfissures, which were predominantly observed in 200,mJ/pulse groups regardless of AS. Poor resin infiltration into peritubular dentin was observed in most regions of adhesive interfaces created by all ASs on laser-irradiated dentin, resulting in thin resin tags with neither funnel-shaped morphology nor lateral resin projections. Conclusion Laser irradiation of dentin surfaces at 120 or 200,mJ/pulse resulted in morphological changes in HL and resin tags for all ASs evaluated in the study. Lasers Surg. Med. 42:662,670, 2010. © 2010 Wiley-Liss, Inc. [source] A study of the synergistic effect of a triazine-dithiocarbamate derivative with tcp in vegetable oilLUBRICATION SCIENCE, Issue 4 2005Z. Y. He Abstract A novel, potential ashless S,N-style additive, 2-(N,N-dibutylamino)-4,6-bis-(dibutyldithiocarbamate)-1,3,5-triazine (DBTT), was synthesised and its synergistic tribological effect with a traditional additive, tricresyl phosphate (TCP), in rape seed oil was evaluated using a four-ball tester. The results show that the load-carrying capacity of the vegetable oil could be improved greatly by the presence of the TCP and/or DBTT additives; at certain mass ratios TCP and DBTT show a good synergistic effect in improving the tribological performance of the base oil. The elemental composition and chemical nature of antiwear films generated at a steel interface were investigated using Kevex energy dispersive X-ray analysis and X-ray photoelectron spectroscopy. Scanning electron microscopy was also used to study the rubbed surface morphology. It was found that FeS, organosulphur compound, sulphate, phosphate, and nitrogen-containing compounds were present in the complex boundary lubrication film. [source] Preparation and evaluation of vegetable oil derived biodiesel esters as lubricity additivesLUBRICATION SCIENCE, Issue 2 2001X. Lang Abstract Various vegetable-oil derived esters using methyl, ethyl, butyl, and 2-propyl alcohols were prepared and tested as diesel fuel lubricity additives in a roller-on-cylinder lubricity evaluator. At1% additive treat rate, the canola methyl and 2-propyl esters, the best-performing esters, increased the lubricity number of a reference fuel by 60%. Statistical analyses indicated strong effects of fatty acids and alcohols on the wear, friction, and lubricity number of the fuel. While no single fatty acid was identifiably responsible for the wear reduction, certain non-linoleic compounds correlated with the wear data in a semi-log relationship. The low-temperature behaviour of the biodiesel was studied using differential scanning calorimetry. The major transitional peak temperature of the biodiesel esters changed with the melting points of their primary fatty acids, and decreased with the lengthening and branching of the tail alkyl groups. [source] Polyurethanes Based on Castor Oil: Kinetics, Chemical, Mechanical and Thermal PropertiesMACROMOLECULAR MATERIALS & ENGINEERING, Issue 11 2008Elodie Hablot Abstract Polyurethanes based on vegetable oil were synthesized with castor oil and toluene diisocyanate, isophorone diisocyanate or hexamethylene diisocyanate, using dibutyltin dilaurate as a catalyst. The effects of the nature of the diisocyanate on the evolution of the kinetics, as well as the physical and mechanical properties and the thermal stability, of the different synthesized polyurethanes were investigated, and these complement data from the literature on equivalent systems. The polymerization kinetics, degree of swelling and mechanical properties were greatly affected by the diisocyanate nature, whereas the rheological properties and thermal stability were found to be similar for all polyurethanes. [source] Gel point prediction of metal-filled castor oil-based polyurethanes system,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 10-12 2002Anil Srivastava Abstract Prediction of gel point conversion and network formation is of great importance in polycondensation during synthesis as well as processing. It enables one to estimate the safe conversions for reactor operation without gelation and the cycle time during processing, and plays an important role in controlling the molding parameters used for reinforced reaction injection molding (RRIM), reaction injection molding (RIM) and compression molding. Theories of gelation have been extensively published in the literature and supported by experimental data for various polycondensation systems. However, most such studies relate to unfilled systems. In this work, metal-filled polyurethanes have been synthesized in bulk by reacting toluene di-isocyanate with castor oil and its polyols possessing different hydroxyl values. Metallic aluminum powder (10,40% by weight) was dispersed thoroughly in castor oil and its polyols before reacting at different temperatures (30,60,°C) in a moisture-free, inert environment. The gel point conversions were measured experimentally and an empirical model from the experimental data has been developed to predict the gelation behavior. The proposed model could be of immense importance in the paints, adhesives and lacquers industries, which use castor oil in bulk. From these experiments it was concluded that: (i) fine metal powder gives a rise in viscosity; (ii) metal fillers not only restrict the molecular motion due to the increase in viscosity, but also lower the conversion; (iii) the vegetable oil and its polyols have a number of bulky groups, which also impart the delay tendency in gel time; (iv) there is a change in gelation dynamics at 50,°C , this is due to the change in reactivity of di-isocyanates; (v) the presence of metal filler does not initiate the intermolecular condensation; (vi) there is a gap between theoretical and experimental gel point owing to the unequal reactivity of the secondary alcohol position; (vii) there is an inverse relationship of gel time with the reaction temperature and hydroxyl value of polyols. An empirical model based on process parameters, i.e., hydroxyl value, temperature, shape factor and filler concentration, has been derived and found to be adequate for the metal-filled system. The correlation coefficient on the data is on the lower side in some cases because the following were not taken into account: (i) the first-order kinetics followed by the reaction in the second half while it is tending towards gelation; (ii) the error in observing the gel point viscosity; (iii) errors in assuming the spherical shape of aluminum metal powder; (iv) errors due to failure to maintain the constant speed in agitation. Copyright © 2003 John Wiley & Sons, Ltd. [source] Chemical study of triterpenoid resinous materials in archaeological findings by means of direct exposure electron ionisation mass spectrometry and gas chromatography/mass spectrometryRAPID COMMUNICATIONS IN MASS SPECTROMETRY, Issue 11 2006Francesca Modugno A systematic study of standard triterpenes (, -amyrine, oleanolic acid, betulin, lupeol, betulinic acid and lupenone) and of raw resinous materials (frankincense resin, mastic resin and birch bark pitch) was performed using direct exposure electron ionisation mass spectrometry (DE-MS) and gas chromatography/mass spectrometry (GC/MS). DE-MS provides a mass spectral fingerprint of organic materials in a few minutes which highlights the compounds that are the main components in the sample. The application of principal component analysis (PCA) on DE-MS data in the mass ranges m/z 181,260 and m/z 331,500, corresponding to the fragmentation of triterpenoid molecules, enabled us to distinguish between different triterpenoid materials such as mastic resin, frankincense resin and birch bark pitch, and to graphically plot the resinous substances in three separate clusters, retaining 89% of the total variance. GC/MS analysis of the same materials has permitted us to elucidate in detail the molecular composition and to identify minor components and species that act as markers of the degradation undergone by the materials. The paper also reports the results for the organic residues contained in an Egyptian censer (5th,7th century AD) which was recovered in the excavation of the Necropolis of Antinoe (Egypt), and for the hafting material found on a Palaeolithic tool recovered at the site of Campitello (Arezzo, Tuscany), dating back to the Mid-Pleistocene period. Although DE-MS was found to be a fast analytical tool, it failed to give any information on the presence of less abundant compounds when applied to mixtures of different materials: only mastic resin was found in the residues from the Roman censer, whereas GC/MS analysis identified the presence of a vegetable oil from Brassicaceae seeds and Pinaceae resin. Birch bark pitch as a pure material was identified in the sample from the Palaeolithic flint flake using both procedures. Copyright © 2006 John Wiley & Sons, Ltd. [source] Gene expression of fatty acid-binding proteins, fatty acid transport proteins (cd36 and FATP) and ,-oxidation-related genes in Atlantic salmon (Salmo salar L.) fed fish oil or vegetable oilAQUACULTURE NUTRITION, Issue 4 2009B.E. TORSTENSEN Abstract Relative gene expression pattern of fatty acid transport proteins (FATP and cd36), intracellular fatty acid-binding proteins (FABP3, FABP10 and FABP11), ,-oxidation-related genes [carnitine palmitoyl transferase II (CPTII), peroxisome proliferator-activated receptor , (PPAR,), acyl-CoA oxidase (AOX), long-chain fatty acyl-CoA synthetase (FACS), acyl-CoA dehydrogenase (dehydrogenase)] and uncoupling protein 2 (UCP2) was assessed by RT-qPCR in Atlantic salmon muscle (red and white), liver, heart, myosepta and visceral fat. FABP11, a FABP isoform not previously described in Atlantic salmon, was highly expressed in visceral fat and myosepta and at the lower level in red muscle, white muscle, myosepta and heart. Furthermore, Atlantic salmon were fed either a diet containing fish oil (FO) or a complete replacement of FO with a vegetable oil blend (55% rapeseed oil, 30% palm oil and 15% linseed oil; VO) for the production cycle (27 months from start of feeding and until ,4.5 kg mean weight). The expression of genes related to ,-oxidation, fatty acid uptake and transport in the white muscle indicate (n = 3) significant down-regulation in VO fed Atlantic salmon and correlated with previously reported white muscle triacylglycerol stores and ,-oxidation. FABP11 in visceral fat and myosepta was also down-regulated in VO fed fish. [source] Growth performance, feed efficiency and fatty acid composition of juvenile Murray cod, Maccullochella peelii peelii, fed graded levels of canola and linseed oilAQUACULTURE NUTRITION, Issue 5 2007D.S. FRANCIS Abstract In two independent experiments, the effects of dietary inclusion of canola and linseed oil were evaluated in juvenile Murray cod (Maccullochella peelii peelii, Mitchell) over a 112-day period. In each experiment, fish received one of five semi-purified diets in which the dietary fish oil was replaced with canola oil (Experiment A) or linseed oil (Experiment B) in graded increments of 25% (0,100%). Murray cod receiving the graded canola and linseed oil diets ranged in final weight from 112.7 ± 7.6 to 73.8 ± 9.9 g and 93.9 ± 3.6 to 74.6 ± 2.2 g, respectively, and exhibited a negative trend in growth as the inclusion level increased. The fatty acid composition of the fillet and liver were modified extensively to reflect the fatty acid composition of the respective diets. Levels of oleic acid (18:1 n-9) and linoleic acid (18:2 n-6) increased with each level of canola oil inclusion while levels of , -linolenic acid (18:3 n-3) increased with each level of linseed oil inclusion. The concentration of n-3 highly unsaturated fatty acids in the fillet and liver decreased as the amount of vegetable oil in the diets increased. It is shown that the replacement of fish oil with vegetable oils in low fish meal diets for Murray cod is possible to a limited extent. Moreover, this study reaffirms the suggestion for the need to conduct ingredient substitution studies for longer periods and where possible to base the conclusions on regression analysis in addition to anova. [source] Finishing diets stimulate compensatory growth: results of a study on Murray cod, Maccullochella peelii peeliiAQUACULTURE NUTRITION, Issue 5 2007G.M. TURCHINI Abstract The effective implementation of a finishing strategy (wash-out) following a grow-out phase on a vegetable oil-based diet requires a period of several weeks. However, fish performance during this final stage has received little attention. As such, in the present study the growth performance during both, the initial grow-out and the final wash-out phases, were evaluated in Murray cod (Maccullochella peelii peelii). Prior to finishing on a fish oil-based diet, fish were fed one of three diets that differed in the lipid source: fish oil, a low polyunsaturated fatty acid (PUFA) vegetable oil mix, and a high PUFA vegetable oil mix. At the end of the grow-out period the fatty acid composition of Murray cod fillets were reflective of the respective diets; whilst, during the finishing period, those differences decreased in degree and occurrence. The restoration of original fatty acid make up was more rapid in fish previously fed with the low PUFA vegetable oil diet. During the final wash-out period, fish previously fed the vegetable oil-based diets grew significantly (P < 0.05) faster (1.45 ± 0.03 and 1.43 ± 0.05, specific growth rate, % day,1) than fish continuously fed with the fish oil-based diet (1.24 ± 0.04). This study suggests that the depauperated levels of highly unsaturated fatty acids in fish previously fed vegetable oil-based diets can positively stimulate lipid metabolism and general fish metabolism, consequently promoting a growth enhancement in fish when reverted to a fish oil-based diet. This effect could be termed ,lipo-compensatory growth'. [source] Effects of alternate phases of fish oil and vegetable oil-based diets in Murray codAQUACULTURE RESEARCH, Issue 10 2009David S Francis Abstract Fish oil (FO)- and canola oil (CO)-based diets were regularly alternated in a daily cycle (amCO: alternation of CO in the morning and FO in the afternoon, and pmCO: alternation of FO in the morning and CO in the afternoon) or in a series of weekly cycles (2W: alternation of 2 weeks on CO and 2 weeks on FO, 4W: alternation of 4 weeks on CO and 4 weeks on FO), over a 16-week period in juvenile Murray cod (Maccullochella peelii peelii). No significant differences were observed between any of the treatments in relation to the final weight. However, fish subjected to the 2W schedule were larger (P>0.05) than all other treatments (37.2 ± 0.30 vs. 34.3 ± 0.58 in the control treatment). Fish receiving the 2W treatment had a significantly lower total net disappearance of eicosapentaenoic acid 20:5n-3 (EPA) and docosahexaenoic acid 22:6n-3 (62.1% and 24.0% respectively) compared with the control treatment (fish continuously fed a blend of 50% FO and 50% CO). Likewise, Murray cod receiving the amCO daily schedule had a significantly lower total net disappearance of EPA in comparison with the CD and pmCO treatments. These data point towards the existence of cyclical mechanisms relative to fatty acid utilization/retention. [source] Direct use of vegetable oil and animal fat as alternative fuel in internal combustion engineBIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 2 2008Pinaki Mondal Abstract Gradual depletion of world petroleum reserves and the impact of environmental pollution of increasing exhaust emissions lead to the search for a suitable alternative fuels for diesel engines. The substitution of conventional fuels (gasoline, diesel) by renewable biofuels is considered a potential way to reduce pollution and to support the sustainable development of a country. Direct use of vegetable oil and animal fat is a promising alternative to solve these problems. An exhaustive review of the experiments in this area, carried out by several researchers in last three decades, is presented here. Different problems associated with the direct use of vegetable oil and animal fat and potential solutions from both public and private sectors are discussed. Some engine manufacturers have started to launch full-warranty engines with vegetable oil as fuel. It is expected that the competitive engine market will witness more intense research, resulting in the launch of more vegetable-oil engines with full warranties. The steep rise in food prices in recent years is concerning policy-makers and has raised the old ,food vs fuel' debate. It has been concluded that vegetable oil can probably only substitute small to medium portions of petroleum-based fuel due to future severe land-usage competition from food sector. This calls for intense research initiatives into the production of suitable fuel from non-edible vegetable oil, grown in wasteland. In this regard, genetic engineering may prove to be extremely effective in developing ,designer fuel'. © 2008 Society of Chemical Industry and John Wiley & Sons, Ltd [source] The maternal Mediterranean dietary pattern is associated with a reduced risk of spina bifida in the offspringBJOG : AN INTERNATIONAL JOURNAL OF OBSTETRICS & GYNAECOLOGY, Issue 3 2009M Vujkovic Objective, The objective of this study was to test the hypothesis whether a maternal dietary pattern is associated with the risk of spina bifida (SB) in the offspring. Design, Case,control study. Setting, Eight clinic sites in the Netherlands, 1999,2001. Sample, A total of 50 mothers of children with SB and 81 control mothers. Methods, Maternal food intakes were obtained by food frequency questionnaires at the standardised study moment of 14 months after the birth of the index child. Principal component factor analysis (PCA) and reduced rank regression (RRR) were used to identify dietary patterns. Main outcome measures, Maternal biomarkers were used as response measures in the RRR analysis and composed of serum and red blood cell (RBC) folate, serum vitamin B12 and total plasma homocysteine. The strength of the use of the dietary pattern in association with SB risk was estimated by odds ratios and 95% CI with the highest quartiles of the dietary pattern as reference. Results, A predominantly Mediterranean dietary pattern was identified by both PCA and RRR. Those dietary patterns were highly correlated (r = 0.51, P < 0.001) and characterised by joint intakes of fruit, vegetables, vegetable oil, alcohol, fish, legumes and cereals and low intakes of potatoes and sweets. We observed a significantly increased risk of SB offspring in mothers with a weak use of the Mediterranean dietary pattern, OR 2.7 (95% CI 1.2,6.1) and OR 3.5 (95% CI 1.5,7.9). The Mediterranean dietary pattern was correlated with higher levels of serum and RBC folate, serum vitamin B12 and lower plasma homocysteine. Conclusion, The Mediterranean dietary pattern seems to be associated with reduction in the risk of offspring being affected by SB. [source] | ||||||||||||||||||||||||||||||||||||||||||||||