bluuebunny/crossref_metadata_2025_split huggingface dataset:
Silver ion high‐performance liquid chromatography of the triacylglycerols ofCrepis alpina seed oil
Authors: Neff W. E. , Adlof R. O. , El‐Agaimy M. 
Published: January 2007

AbstractThe triacylglycerols ofCrepis alpina oil were characterized because this oil has a high concentration of crepenynic (cis‐9‐octadecen‐12‐ynoic) acid, a fatty acid useful in the chemical synthesis of deuterated fats for human metabolism studies. The triacylglycerols were separated from the crude oil by solid‐phase extraction. Resolution, quantitation and isolation of the individual triacylglycerols were performed by silver ion high‐performance liquid chromatography on a commercial column, an acetonitrile in hexane isocratic mobile phase and flame‐ionization detection. Isolated triacylglycerols were identified by capillary gas chromatography of their fatty acid methyl esters. Of the eleven eluted triacylglycerols ofCrepis alpina oil, 85% included 35% tricrepenynoyl, 34% linoleoyldicrepenynoyl and 16% dilinoleoylcrepenynoyl glycerols. Triacylglycerols eluted according to the numbers of alkene and alkyne bonds. Elution times, resolution and quantitation were reproducible over a three‐month period. The flame‐ionization detector response required no response factors for quantitation of the triacylglycerols present inCrepis alpina oil. The silver ion chromatography system permitted the identification of 95% of the triacylglycerols compared to 70% of the triacylglycerols previously identified with reversed‐phase high‐performance liquid chromatography.
Electron impact mass spectra of the oxazoline derivatives of some conjugated diene and triene C18 fatty acids
Authors: Spitzer V. , Marx F. , Pfeilsticker K. 
Published: January 2007

AbstractThe location of the double‐bond systems of some conjugated diene and triene C18 fatty acids (C18∶2[9,11], C18∶2[10,12], C18∶3[9,11,13] and C18∶3[10,12,14]) derived from alkaline isomerization has been determined by gas chromatography/mass spectroscopy analysis of their 4,4‐dimethyloxazoline derivatives. The positions of the double bonds were indicated by a characteristic mass separation of 12 atomic mass units for each olefinic bond. Furthermore, the structure assignments were supported by the presence of prominent formal allylic cleavage peaks.
Determination of trace elements in edible vegetable oils by atomic absorption spectrophotometry
Authors: Martín‐Polvillo M. , Albi T. , Guinda A. 
Published: January 2007

AbstractMethods are described for the direct determination of Al, Cr, Cu, Fe, Ni and Pb by atomic absorption spectrophotometry in sunflower oil and olive oils. Metallic contamination after storage under different controlled conditions and in contact with carbon steel, austenitic steel, ferritic steel and aluminum was examined. Additionally, chemical characteristics related to quality (acid value, peroxide value, K270and oxidative stability) and some physical parameters of interest were evaluated after storage. When the samples were atomized directly off the tube wall, matrix interferences were not observed in the determination of Cr, Cu, Ni and Pb, whereas such interferences were noted when Al and Fe were determined. The results indicated that the L'Vov platform for Al and Fe determinations eliminates the matrix effects. Contamination with Fe was only detected in the olive oil that had been in contact with carbon steel, Fe concentration increased from 120±12 to 3,520±157 ppb. The physicochemical characteristics were affected only by the storage conditions, regardless of the metal sheets with which they were in contact. Virgin olive oil showed lowered stability after storage in contact with a carbon‐steel sheet than when stored in absence of metal.
Separation and characterization of pigments from bleached and deodorized canola oil
Authors: Chapman D. M. , Pfannkoch E. A. , Kupper R. J. 
Published: January 2007

AbstractAn analysis of pigments responsible for color formation during bleaching and deodorization of canola oils treated with activated bleaching earth (ABE) or novel mineral‐acid/silica (AS) adsorbents is presented. The chromophores are trace glycerides and were concentrated by silica column chromatography. The concentrated color bodies were hydrolyzed and analyzed as free acids or methyl esters by reversed‐phase high‐performance liquid chromatography with photodiode array and mass spectrometry detection,1H and13C nuclear magnetic resonance and infrared spectroscopies. Absorbance in deodorized oils is mostly from oxygenated C18 and C20 fatty acids with 1 to 4 double bonds. High‐wavelength absorbance in AS‐bleached oils is from conjugated pentane fatty acids that are not observed for ABE‐bleached oils. Thus, both the bleaching agent and the deodorization treatment affect the distribution and concentration of such stable chromophores.
Effects of crystallization conditions on sedimentation in canola oil
Authors: Liu H. , Biliaderis C. G. , Przybylski R. , Eskin N. A. M. 
Published: January 2007

AbstractThe effects of various factors on sediment formation in canola oil were studied. The crystallization temperature of sediment varied with cooling rate, whereas the melting temperature depended on heating rate as well as the cooling rate during sediment formation. The final crystal size depended on cooling rate. The crystal habit of sediment was generally rod‐like but could change to a round and leaf‐like shape at low cooling rates (<0.5°C/min). Crystal nucleation occurred in the initial stage of crystallization, while crystal growth was observed during the whole crystallization process, decreasing as cooling proceeded. Crystal growth rate of the sediment was proportional to the crystal surface area Lecithin did not affect the phase transition temperatures of sediment, but retarded crystal growth.
Sensory stability of canola oil: Present status of shelf life studies
Authors: Malcolmson L. J. , Vaisey‐Genser M. , Przybylski R. , Eskin N. A. M. 
Published: January 2007

AbstractSensory studies on autoxidation of canola oil, stored under several variations of Schaal Oven test conditions, suggest an induction period of 2–4 d at 60–65°C. Similar induction periods have been observed between canola and sunflower oils, whereas a longer induction period has been found for soybean oil. Canola oil seems to be more stable to storage in light than cottonseed and soybean oils but is less stable than sunflower oil. Storage stability of products fried in canola oil is similar to products fried in soybean oil. Storage stability of canola and cottonseed oils that had been used in the frying of potato chips showed that canola oil was more prone to autoxidation during storage at 40°C. The presence of light aggravated the oxidative effects and was similar for both oils. Advances in our knowledge about the shelf life of canola oil would be strengthened by standardization of Schaal Oven testing conditions and by specifying the testing protocol for photooxidation studies. Methods for training of panelists and for handling and evaluating oils and fried foods require definition. Rating scales used in the evaluation of oils need to be evaluated to ensure that reliable and valid measurements are achieved. Further progress is needed in the identification of chemical indicators that can be used to predict sensory quality of oils.
Separation of monoacylglycerols by high‐performance liquid chromatography on nitrile‐bonded phase
Authors: Takagi Toru , Ando Yasuhiro 
Published: January 2007

AbstractMonoacylglycerol molecular species, as their di‐3,5‐dinitrophenylurethane derivatives, were well separated by normalphase high‐performance liquid chromatography on nitrilebonded phase. The peaks emerged in the order 20∶0, 18∶0, 16∶0, 18∶1, 16∶1, 18∶2, and 18∶3. The peaks of 1‐ and 2‐monoacylglycerols with the same acyl group showed complete overlapping. This method could be applied to get acyl compositions in the three positions of triacyl‐sn‐glycerols in their stereospecific analysis.
Microwave heating of cottonseed: A pilot plant study
Authors: Conkerton E. J. , Chapital D. C. , Wan P. J. 
Published: January 2007

AbstractTwo cottonseed samples (50 kg) were exposed to microwaves at 45 KW and 2450 MHz for 4 min in an air temperature of 94°C. The final temperature of the seed was 76°C, and the treatment caused a 20% reduction in seed moisture. Examination of the seed immediately after microwave heating (MWH) indicated no differences in the total or soluble protein content of the meal or the content, quality or color of the oil as compared with unheated seed. There was some reduction in the quality of the oil from unheated seed during storage, but only minimal reduction in the quality of the oil from the MWH samples. Protein quality deteriorated in all samples; however, the deterioration was reduced in the microwave‐heated seed.
Preferential degradation of noncholine phosphatides in soybean lecithin by thermalization
Authors: Weete John D. 
Published: January 2007

AbstractPurified soybean lecithin and the gum derived from soybean oil processing were heated separately in bulk at 125 to 200°C for 60 min, or at 175°C for 30, 60, 90 and 120 min, and the products were analyzed by thin‐layer chromatography and high‐performance liquid chromatography. It was found that the noncholine phosphatides are preferentially degraded relative to phosphatidylcholine, and that these phosphatides are broken down in the order phosphatidyl‐ethanolamine (PE)>phosphatidylinositol (PI)>phosphatidic acid (PA) with increasing temperature. At 175°C, the heating time required to degrade the noncholine phosphatides was between 30 and 60 min. Diglycerides were the principal products of thermalization at 77% of the total material, indicating that the 3‐phosphoester linkage is the most heat‐labile portion of the noncholine phosphatide molecules. Cleavage of the fatty acids from positions 1 and 2 of the phosphatides was minimal, as indicated by the relatively low amount of free fatty acids (8% of the total) when the lecithin was heated at 180°C for 90 min. The appearance of brown discoloration, characteristic of heated lecithin, coincided mainly with the decomposition of PE.
Antioxidant constituents of peanut oil
Authors: Gopala Krishna A. G. , Prabhakar J. V. 
Published: January 2007

AbstractThe components responsible for increased stability of raw peanut oil at a high relative humidity (RH) of 91% were examined in peanut oil and methyl linoleate systems. Of the constituents, the native gums, which were mostly phospholipids and glycolipids, showed increased antioxidant activity at 91% RH. The isolated components of the gums, namely phospholipids and glycolipids, were prooxidant individually or in combination. Tocopherols did not show increased antioxidant activity at 91% RH.
Effect of saline irrigation water on olive oil composition
Authors: El‐Agaimy M. A. , Neff W. E. , El‐Sayed M. , Awatif I. I. 
Published: January 2007

AbstractVirgin olive oils were obtained in Egypt from fruits of olive trees irrigated with waters of different salinity concentration (control, 1800, 3600 and 6000 ppm) during the 1992 season. The effect of water salinity on olive oil fatty acid, fatty acid location in triacylglycerol moiety, triacylglycerol, sterol and tocopherol composition was determined. Oleic acid slightly increased and linoleic decreased in the total fatty acid composition, as well as on glycerol carbon‐2 and‐1(3), with increased water salinity. Trioleoyl, stearoyldioleoyl and palmitoyldioleoyl glycerols are slightly increased with increased water salinity. Total tocopherol was 87.7 mg/kg in the control and increased to 147.0 mg/kg for water with 1800 ppm salinity. At higher salinity concentration, total tocopherol decreased to 107.2 and to 89.1 mg/kg for water salinities of 3600 and 6000 ppm, respectively. The same trend was observed for α, β and γ‐tocopherols. Campesterol and β‐sitosterol were increased with water salinity of 1800 ppm and decreased when water salinity increased further. Stigmasterol increased at water salinity of 3600 ppm and decreased sharply when the salinity was increased to 6000 ppm. These olive oil composition studies showed that although water salinity may have some compositional effects, there was no major adverse effect on fatty acid, triacylglycerol, triacylglycerol fatty acid location, sterol and tocopherol composition for oil from olives of trees grown with water with a salt composition of up to 6000 ppm.
Protein nitrogen combustion method collaborative study I. Comparison with smalley total Kjeldahl nitrogen and combustion results
Authors: Berner David L. , Brown Janet 
Published: January 2007

AbstractDuring 1993–1994, a collaborative study of the determination of the nitrogen content of oilseed meals by the nitrogen combustion method was conducted among 24 laboratories in seven countries for the analysis of cottonseed, soybean (two samples), peanut, canola and safflower (two samples). These meals were also analyzed by the CuSO4/TiO2 Kjeldahl method (Official Methods and Recommended Practices of the American Oil Chemists' Society, 4th edn., 1989, Method Ba 4d‐90) in the 1993–1994 Smalley Check Sample Program Oilseed Meal Series [Brown, J.,INFORM 5:640 (1994)]. Some participants used commercial nitrogen combustion instruments. In the Smalley Program, CuSO4/TiO2 Kjeldahl analysis gave nitrogen values that ranged from 0.05 to 0.13% lower than values obtained by the combustion method in the collaborative study. Nitrogen values obtained by the combustion method on an optional basis in the Smalley Program were generally lower by 0.01 to 0.03% than nitrogen values obtained by the combustion method in the collaborative study reported here.
γ‐Linolenic acid concentrates from borage and evening primrose oil fatty acidsvia lipase‐catalyzed esterification
Authors: Syed Rahmatullah M. S. K. , Shukla V. K. S. , Mukherjee K. D. 
Published: January 2007

Abstractγ‐Linolenic acid (GLA, all‐cis 6,9,12‐octadecatrienoic acid) has been enriched from fatty acids of borage (Borago officinalis L.) seed oil to 93% from the initial concentration of 20% by lipase‐catalyzed selective esterification of the fatty acids withn‐butanol in the presence ofn‐hexane as solvent. The immobilized fungal lipase preparation, Lipozyme, used as biocatalyst, preferentially esterified palmitic, stearic, oleic and linoleic acids and discriminated against GLA, which was thus concentrated in the unesterified fatty acids fraction. In the absence of hexane, concentrate containing about 70% GLA was obtained. When the reaction conditions, optimized for borage oil fatty acids, were applied to fatty acids of evening primrose (Oenothera biennis L.) oil, concentrates containing 75% GLA were obtained. From both oils, GLA concentrates were prepared efficiently in short reaction times (1–3 h) at 30–60°C. The process can be applied for the production of GLA concentrates for dietetic purposes.
Acidolysis of babassu fat catalyzed by immobilized lipase
Authors: Gioielli L. A. , Pitombo R. N. M. , Vitolo M. , Baruffaldi R. , Oliveira M. N. , Augusto M. S. 
Published: January 2007

AbstractThe lipase‐catalyzed interesterification of oils and fats gives products that are unobtainable by chemical interesterification methods. Acidolysis of babassu fat and palmitic acid, catalyzed by immobilized lipase (Lipozyme; Novo Industri, Bagsveard, Denmark), was studied. The reactions were performed at 65°C with 5% w/w enzyme for 4 h. The molar proportions of babassu fat/palmitic acid were 1∶0.1, 1∶0.3 and 1∶0.5. At the end of the reaction period, the catalyst particles were removed by filtration, and the residual oil was extracted with organic solvent (diethyl ether). The recovered particles were then reused. The palmitic acid content of babassu fat before and after acidolysis changed from 10 to 22% at a molar proportion of 1∶0.5. The equilibrium was attained in about 4 h. The original water and enzymatic activities of Lipozyme were maintained after acidolysis. Water sorption isotherms of the immobilized enzyme were determined at 25, 35 and 45°C. From the temperature dependence of the isotherms, isosteric heats of sorption were evaluated by means of the Clausius Clapeyron equation. Monolayer moisture content was calculated by means of the B.E.T. and Guggenhein‐Anderson‐De Boer analyses.
Synthesis of mono‐ and diglycerides in water‐in‐oil microemulsions
Authors: Singh C. P. , Shah D. O. , Holmberg Krister 
Published: January 2007

AbstractEnzyme‐catalyzed esterification was carried out in single‐phase, oil‐continuous microemulsions. The lipozyme was solubilized, along with glycerol and water, in the aqueous core of water/diethylhexyl sodium sulfosuccinate/hydrocarbon microemulsion system. Upon addition of fatty acid, mono‐ and diglycerides were formed, due to the esterification reaction taking place at the interface of the droplets in the microemulsion. The initial rate of conversion of oleic acid increases with oil chainlength of the continuous phase whereas final conversion is maximum for hexane. The conversion of stearic acid is 30% whereas conversion of oleic acid is 70%. The percent conversion of various fatty acids in the same continuous medium increases with fatty acid chainlength. The oleic acid/glycerol ratio is an important parameter for optimum conversion of oleic acid into glycerides. The yield can be increased by subsequent addition of glycerol after equilibrium is reached. High‐performance liquid chromatography analysis of samples from microemulsions shows the presence of mono‐ and diglycerides. Possible mechanisms for the abovementioned effects are discussed.
Bleaching rapeseed and soybean oils with synthetic adsorbents and attapulgites
Authors: Boki Keito , Mori Hidehito , Kawasaki Naohito 
Published: January 2007

AbstractEfficiencies of synthetic adsorbents and attapulgites in bleaching alkali‐refined rapeseed and soybean oils ranged from 13–53% and 93–97%, respectively. The Freundlich equation was more applicable than the Langmuir equation to the experimental adsorption isotherms of β‐carotene on attapulgites. Bleaching with attapulgites reduced tocopherols by 12.5–29.5% in rapeseed oil and by 18.9–44.8% in soybean oil. Cosmetic‐grade attapulgite was superior to the others in bleaching efficiency, equilibrium amount adsorbed and removal of free fatty acids.
Antioxidant efficacy of amino acids in methyl linoleate at different relative humidities
Authors: Gopala Krishna A. G. , Prabhakar J. V. 
Published: January 2007

AbstractAntioxidant efficacy of the amino acids methionine, tryptophan, aspartic acid, serine, alanine and arginine in methyl linoleate were compared to a methyl linoleate control at 2,50 or 79% relative humidity (RH) at 37°C. Antioxidant efficacy varied with RH and the individual amino acids. Arginine had the highest antioxidant efficacy at all RH values compared to the control. The efficacy of alanine was equal to that of arginine at RHs of 50 and 79% but was lower at 2% RH. The presence of aliphatic, alkaline amino, hydroxyl or thiol groups in the side chain of the amino acids increased the antioxidant efficacy at high RHs.
Molecular interactions in monolayers: Molecular association and foam stability of fatty acids and alcohols
Authors: Shah Dinesh O. , Dysleski Cynthia A. 
Published: January 2007

AbstractSurface pressures and potentials of monolayers of stearic acid and of mixed monolayers of stearic acid‐stearyl alcohol (1:1 and 1:3 molar ratios) were measured on buffered subsolutions at various pH values. The molecular area‐pH plot for these monolayers at a surface pressure of 10 dynes/cm showed a maximum at pH 9.0. The average area per molecule in the mixed monolayers decreased at pH 9, as the per cent of stearyl alcohol was increased. The foam characteristics of decanoic acid, and 1:1 and 1:3 mixtures of decanoic acid‐decanol solutions were studied at various pH values. At pH 9.0, foams of decanoic acid and of 1:1 mixture of decanoic acid‐decanol had least stability. In contrast, the foam of the 1:3 mixture had maximum stability at pH 9.0. The results suggest that a stoichiometric association between a fatty acid and an alcohol strikingly influences the foam stability.
Dietary fat composition and tocopherol requirement: II. Nutritional status of heated and unheated vegetable oils of different ratios of unsaturated fatty acids and vitamin E
Authors: Alfin‐Slater R. B. , Morris R. B. , Aftergood L. , Melnick D. 
Published: January 2007

AbstractIn studies conducted on male and female rats and involving evaluation of growth, reproductive and lactation performances and of lipid peroxidation, no evidence could be found for the need for added vitamin E (a‐tocopherol) over and above that naturally present as tocopherols in the vegetable oils investigated. These oils are in common usage in industry, i.e., liquid nonhydrogenated cottonseed oil, a lightly hydrogenated cottonseed oil and a hydrogenated soybean oil shortening. The ratio of polyunsaturates to total tocopherol in the test oils varied from 640:1 to 9:1. Even those oils obtained from a commercial frying operation after a steady state had been attained contained sufficient vitamin E to meet dietary requirements. Results of in vitro peroxide hemolysis tests conducted on the red blood cells of the test animals did not correlate well with biological performance.
Surface active properties of sulfonated isoricinoleic acid
Authors: Ahmad Ishtiaque , Singh Jasbhinder 
Published: January 2007

AbstractA new anionic surfactant, sulfonated isoricinoleic acid, was prepared by sulfonation of isoricinoleic acid. Surface active properties, such as surface tension, interfacial tension, emulsifiability, dispersibility and foaming power of sulfonated isoricinoleic acid (SIRA), and sulfonated castor oil or turkey red oil (TRO) were studied and compared. The comparative studies showed that SIRA is a better surface active agent than TRO.
Kinetics of liquid phase hydrogenation of cottonseed oil with nickel catalysts
Authors: Krisnaiah D. , Sarkar S. 
Published: January 2007

AbstractThe hydrogenation of cottonseed oil has been carried out in a batch reactor using both unmodified and chromia modified nickel catalysts. The process variables include chromium to nickel atomic ratio (0.00–0.35), catalyst particle size (200–400 micron), temperature (120–140°C) and pressure (5–10 bar). Chromia was found to suppress the stearate formation completely, although it retarded the overall hydrogenation activity of nickel. Its optimum content in the catalyst was found to be 0.17 Cr/Ni atomic ratio; the data corresponded to 5 hr reaction time. The kinetics of the process was tested and found to follow a first order reaction with respect to linoleate and half order with respect to hydrogen. The activation energy was found to be 11.8 kcal/mole.
Effect of packaging materials on storage stability of crude palm oil
Authors: Nkpa Nnadozie N. , Osanu F. C. , Arowolo T. A. 
Published: January 2007

AbstractLacquered metal cans, green glass bottles, amber glass bottles, clear glass bottles and clear plastic bottles filled with freshly produced Nigerian crude palm oil were stored in direct sunlight (40±1°C) and in the dark (27±1°C). Assessment of the stability of the oils towards hydrolytic and oxidative deterioration was made periodically by measuring the free fatty acid, peroxide and anisidine values over a period of 98 days. The study showed that crude palm oil packaged in plastic bottles and clear glass bottles recorded higher total oxidation values than oils packaged in either lacquered metal cans or amber and green glass bottles. Lacquered metal cans gave the greatest protection against oxidation. Oxidation proceeded faster in cases where the packaging materials were stored in direct sunlight.