bluuebunny/crossref_metadata_2025 huggingface dataset:
Rapeseed oil transesterification by heterogeneous catalysis
Authors: Peterson G. R. , Scarrah W. P.
Published: January 2007

Methyl fatty esters derived from vegetable oils are a promising fuel for direct injection diesel engines. This study's purpose was to identify a heterogeneous catalyst to selectively produce methyl fatty esters from low erucic rapeseed oil. Most experiments were at atmospheric pressure and approximately the corresponding boiling point temperature of the mixture, 60–63 C. However, the catalytic activity of an anion exchange resin was tested at 200 C and 68 atm (1000 psig) and at 91 C and 9.2 atm (135 psig). All samples were analyzed by thin layer chromatography with samples from the elevated temperature and pressure experiments also analyzed by mass spectroscopy. The most promising catalyst examined was CaO·MgO. The activities of the catalysts CaO and ZnO appear to be enhanced with the addition of MgO, therefore the transesterification reaction mechanism may be, in this instance, bifunctional. The anion exchange resin catalyst at 200 C and 68 atm generated substantial amounts of both methyl fatty esters and straight‐chain hydrocarbons, even though these reactions did not go to completion. At 91 C and 9.2 atm the cracking also occurred but at a substantially reduced rate, and no transesterification was noted.
Inorganic phosphate in crude palm oil: Quantitative analysis and correlations with oil quality parameters
Authors: Goh S. H. , Tong S. L. , Gee P. T.
Published: January 2007

A convenient method, not involving ashing or acid digestion, for the determination of inorganic phosphorus content in crude palm oil, is developed. Direct extraction from solvent‐diluted palm oil by dilute acid allows the inorganic phosphates to be analyzed by the usual phosphomolybdenum blue complex. Using this method, phosphate analyses in palm oil samples were correlated with other oil quality parameters and the results discussed.
The effects of vegetable oil properties on injection and combustion in two different diesel engines
Authors: Ryan T. W. , Dodge L. G. , Callahan T. J.
Published: January 2007

Four different vegetable oils, each in at least 3 different stages of processing, have been characterized according to their physical and chemical properties, their injection and atomization characteristics, and their performance and combustion characteristics in both a direct‐injection and an indirect‐injection diesel engine. The injection and atomization characteristics of the vegetable oils are significantly different than those of petroleum‐derived diesel fuels, mainly as the result of their high viscosities. Heating the oils, however, results in spray characteristics more like those observed with diesel fuel. The 2 engine types demonstrated different sensitivities to the composition of the various oils. The combustion characteristics and the durability of the direct‐injection engine were affected by the oil composition. The indirect‐injection engine, however, was not greatly affected by composition. Two different preliminary specifications have been proposed: a stringent specification including compositional requirements for direct‐injection engines, and a less stringent specification for indirect‐injection engines. The specifications are discussed in terms of the data and the rationale used in their development. Some precautions concerning the application of the specifications are also presented.
Methyl and ethyl soybean esters as renewable fuels for diesel engines
Authors: Clark S. J. , Wagner L. , Schrock M. D. , Piennaar P. G.
Published: January 2007

The primary problems associated with using straight soybean oil as a fuel in a compression ignition internal combustion engine are caused by high fuel viscosity. Transesterification of soybean oil with an alcohol provides a significant reduction in viscosity, thereby enhancing the physical properties of the renewable fuel to improve engine performance. The ethyl and methyl esters of soybean oil with commercial diesel fuel additives revealed fuel properties that compared very well with diesel fuel, with the exception of gum formation, which manifested itself in problems with the plugging of fuel filters. Engine performance using soybean ester fuels differed little from engine performance with diesel fuel. A slight power loss combined with an increase in fuel consumption were experienced with the esters, primarily because of the lower heating value of the esters than for diesel fuel. Emissions for the 2 fuels were similar, with nitrous oxide emissions higher for the esters. Measurements of engine wear and fuel‐injection system tests showed no abnormal characteristics for any of the fuels after the 200‐hr tests. Engine deposits were comparable in amount, but slightly different in color and texture, with the methyl ester engine experiencing greater carbon and varnish deposits on the pistons.
New amphoteric surfactants derived from lysine. I. Preparation and properties of Nε‐acyllysine derivatives‐acyllysine derivatives
Authors: Yokota Hirofumi , Sagawa Kouichiro , Eguchi Chikahiko , Takehara Masahiro , Ogino Keizo , Shibayama Toshiro
Published: January 2007

New amphoteric surfactants were prepared from Nε‐acyllysine which was obtained by the thermal dehydration of a higher fatty acid salt of lysine and was not soluble in water. Nα,Nα‐dimethyl‐Nε‐acyllysine was prepared by the catalytic reductive condensation of Nε‐acyllysine ester with formaldehyde in good yield. Nα,Nα,Nα‐trimethyl‐Nε‐acyllysine was obtained from the reaction of Nα,Nα‐dimethyl‐Nε‐acyllysine ester with methyl iodide. Confirmation of the structure of these derivatives was obtained by spectrometric and spectroscopic analyses.

The solubility of Nε‐acyllysine was improved significantly by the introduction of Nα‐methyl groups. Physicochemical and surface active properties of the derivatives were investigated in terms of isoelectric points, dissolution temperatures, surface tensions, critical micelle concentrations (cmc), foaming properties and wetting powers. Nα,Nα,Nα‐trimethyl‐Nε‐acyllysine had lower dissolution temperatures than Nα,Nα‐dimethyl‐Nε‐acyllysine. The latter showed lower surface tensions than the former at cmc. Nα,Nα‐dimethyl‐Nε‐lauroyllysine was best in wetting power and foaming property.
Uses of soybean oil in the application of herbicides
Authors: Kapusta George
Published: January 2007

Field studies were conducted in 1982 and 1983 at Southern Illinois University to evaluate soybean oil as a carrier for preemergence and postemergence herbicides and as an enhancing agent for postemergence herbicides. Preemergence and postemergence herbicides applied with rotary nozzles in a soybean oil carrier volume as low as 5 L/ha afforded weed control equal to that achieved when the herbicides were applied in 187 L/ha water with flat fan nozzles. Soybean oil as an enhancing agent for four postemergence soybean herbicides was equal to petroleum crop oil concentrate with three of the herbicides but distinctly less effective with the fourth herbicide.
Thermochemical applications for fats and oils
Authors: Lipinsky E. S. , Anson D. , Longanbach J. R. , Murphy M.
Published: January 2007

Fats and oils are well established in food, surfactant and coatings applications. Historically, fats and oils were employed to provide lighting and warmth. Increasing production of fats and oils and increasing uncertainties regarding the reliability of petroleum resources make it desirable to reconsider thermochemical applications of fats and oils. Difficulties associated with the use of fats and oils for vehicular applications are discussed, and use in stationary diesel engines is suggested.

Conventional kerosene space heaters are designed to make use of the vaporization behavior of this fuel. Changes in heater design are required to take into account the pyrolytic degradation of the fuel when fats and oils are used, and a traveling grate burner was designed for this purpose.

Pyrolysis of fatty acids at temperatures exceeding 500 C yields a mixture of gaseous and liquid products. The gaseous products include ethylene, but little propylene. The liquid product is primarily a mixture of substituted styrenes.

Further development is needed for these thermochemical applications of fats and oils. Fuel and olefin markets present valuable cushions to keep the price of fats and oils from fluctuating as during the early 1980's, when soybean oil has varied from .15 per pound to .40 per pound. The triglycerides can provide a future source of feedstocks for petrochemicals, if petroleum prices and availabilities change dramatically. Most of the development work needed consists of down‐to‐earth large‐scale experiments in semi‐commercial or commercial equipment to determine the best methods of fuel storage, feeding and conditions for combustion and steam cracking.
Behavior of hydrogenation catalysts. I. Hydrogenation of soybean oil with palladium
Authors: Ray John D.
Published: January 2007

A statistical method for evaluation of catalysts was used to determine the behavior of palladium catalyst for soybean oil hydrogenation. Empirical models were developed that predict the rate,trans‐isomer formation, and selectivity over a range of practical reaction conditions. Two target iodine value (IV) ranges were studied: one range for a liquid salad oil and the other for a margarine basestock. Although palladium has very high activity, it offered no special advantage intrans‐isomer formation or selectivity. Palladium can substitute for nickel catalyst, at greatly reduced temperature and catalyst concentrations, for production of salad oil or margarine basestock from soybean oil.
Empirical modeling of soybean oil hydrogenation
Authors: Ray John D. , Carr B. T.
Published: January 2007

Empirical hydrogenation models were generated from statistically designed laboratory experiments. These models, consisting of a set of polynomial equations, relate the operating variables of soybean oil hydrogenation to properties of the reaction and of the fat produced. These properties include reaction rate,trans‐isomer content and melting point. Operating variables included in the models were temperature, hydrogen pressure, catalyst concentration, agitation rate and iodine value.

The effects of catalyst concentration and agitation rate were found to be significant in determiningtrans‐isomer content, which in turn influences the melting characteristics of the hydrogenated oil. Pressures above 30 psig were found to have little effect ontrans‐isomer content, although pressure was very important in determining reaction rate. Reaction temperature was observed as the most important factor in determining thetrans‐isomer content for a given iodine value. Generally, 50 to 60%trans isomer content is predicted by the model for the iodine value range and operating conditions used in this study. Thus, these predictive models can assist in scaling up hydrogenation processes and in determining the optimum operating parameters for running commercial hydrogenation.
Study of oxidation by chemiluminescence. IV. Detection of low levels of lipid hydroperoxides by chemiluminescence
Authors: Yamamoto Y. , Niki E. , Tanimura R. , Kamiya Y.
Published: January 2007

Sodium hypochlorite (NaOCl) induced decomposition of organic hydroperoxides gave strong chemiluminescence. Chemiluminescence intensity reached its maximum a few seconds after the addition of sodium hypochlorite and decreased to the background level in three min. Good linear relationships were observed between total chemiluminescence counts in three min and the amounts of hydroperoxides. This chemiluminescence method can be applied to the detection of low levels of lipid hydroperoxides.
Polymeric membranes for lipase immobilization
Authors: Rucka Magdalena , Turkiewicz Bożena , Żuk Janusz S.
Published: January 2007

Lipase triacylglycerol acylhydrolase, (E.C. 3.1.1.3) is an enzyme that is fully active on aggregated substrates and practically inactive on monodisperse systems. A lipase immobilized on polymeric membranes has been applied for sunflower oil hydrolysis. The influence of membrane properties on enzyme activity is studied. Membranes made of poly(vinyl chloride), collagen, cellulose acetate and polytetrafluoroethylene were used for adsorption of lipase. The porosity and hydrophobicity of membranes did not influence the lipase activity. The difference of the work of adhesion for the water/membrane system and oil/membrane system reflected the activity data, while work of adhesion for water or oil (done separately) did not. For oil hydrolysis to occur on the membrane surface, accessibility of two liquid phases is important, and the lower the difference of work of adhesion between water and oil, the greater the activity of immobilized lipase.
Immobilized lipase reactors for modification of fats and oils—A review
Authors: Xavier Malcata F. , Reyes Hector R. , Garcia Hugo S. , Hill Charles G. , Amundson Clyde H.
Published: January 2007

This review focuses on the use of immobilized lipase technology to effect hydrolysis, ester synthesis, and interesterification reactions. The various immobilization procedures, reactor configurations, and process considerations are all reviewed and discussed.
Lipid composition ofCalophyllum inophyllum kernel
Authors: Hemavathy J. , Prabhakar J. V.
Published: January 2007

Total kernel lipids extracted fromCalophyllum inophyllum, Guttifereae amounted to 60.1% of the dry kernel. The total lipids consisted of 92.0% of neutral lipids, 6.4% glycolipids and 1.6% phospholipids. Neutral lipids consisted of triacylglycerols (82.3%), free fatty acids (7.4%) and small amounts of diacylglycerols, monoacylglycerols and sterols. At least four glycolipids and five phospholipids were identified. Acylmonogalactosyldiacylglycerol and monogalactosylmonoacylglycerol were major glycolipids; while monogalactosyldiacylglycerol and an acylated sterolglucoside were present in small amounts. The phospholipids consisted of phosphatidylethanolamine and phosphatidylcholine as major phospholipids, and minor amounts of phosphatidic acid, phosphatidylserine and lysophosphatidylcholine. The fatty acid composition of these different neutral lipids, glycolipids and phospholipids was determined.
Subcellular localization of lipoxygenase‐1 and‐2 in germinating soybean seeds and seedlings
Authors: Song Youngsun , Love Mark H. , Murphy Patricia
Published: January 2007

The subcellular localization of lipoxygenase‐1 and‐2 in the cytoledons of germinating soybean seeds [Glycine max (L.) Merr. AmSoy] and seedlings was investigaed by direct labeling with immnogold complexes. Both lipoxygenase‐1 and‐2 were localized in the cytoplasm of all cotyledon cells. No gold labeling was observed on mitochondria, glyoxysomes, protein bodies, lipid bodies, or other organelles.
Determination of peroxide value by conventional difference and difference‐derivative spectrophotometry
Authors: Lezerovich Alberto
Published: January 2007

The spectrophotometric behavior of the system iodide‐iodine‐iodate‐oxygen was studied, and a simple iodometric method to determine peroxide value by conventional, difference or difference‐derivative spectrophotometry was developed. The procedures are carried out inside standard photometric cells containing iodide solution to which the sample is added. Absorbance or its first derivative with respect to wavelength is measured to determine iodine concentration by means of calibration curves. No special care to avoid iodide oxidation by atmospheric oxygen is necessary.

The method is applicable even to lipids that give emulsions with water, such as phosphatides, and precise results are obtained even at low peroxide values.

The use of a digital spectrophotometer with data processing and programming facilities allowed development of an interactive program for automatic operation, which is outlined.
Analysis of fatty acid methyl esters with high accuracy and reliability. IV. Fats with fatty acids containing four or more carbon atoms
Authors: Bannon Cecil D. , Craske John D. , Hilliker Audrey E.
Published: January 2007

Those aspects of the quantitative methanolysis of fats with fatty acids containing four or more carbon atoms and the gas liquid chromatographic analysis of the methyl esters which have not been adequately dealt with to date were investigated. Accurate analysis of the esters requires the optimization of the total chromatographic system using a carefully prepared methyl ester primary standard and applying, as the only correction factors, the theoretical flame ionization detector response factors of Ackman and Sipos. These factors now have also been shown to be highly accurate for short chain saturated fatty acid methyl esters, in particular methyl butyrate and methyl caproate. Under the conditions specified by the international methods for the methylation (methanolic KOH) of fats with fatty acids containing four or more carbon atoms, saponification of the esters, once formed, proceeds much more rapidly for short chain than for long chain esters. This problem is easily overcome by neutralizing the catalyst, which then leads to very stable solutions and contributes to column life. This step should be mandatory in the international procedures. Tristearin methylated more slowly than other triacylglycerols under the standard conditions, but there was no difficulty in the case of unsaturated fatty acids of this chain length. Satisfactory results could not be obtained when sodium methoxide was the catalyst. The optimum procedure rendered unnecessary the use of methyl pentanoate as an internal standard for the accurate quantitation of methyl butyrate.
Effects of β‐carotene on light stability of soybean oil
Authors: Warner K. , Frankel E. N.
Published: January 2007

β‐Carotene was added to soybean salad oils to study its effect in inhibiting flavor deterioration due to light exposure. Flavor evaluations indicated that (a) when oils treated with citric acid were exposed to light (7535 lux) for 8 to 16 hr, oils containing 5 to 10 ppm β‐carotene showed improved flavor stability compared to oils containing 0 to 1 ppm β‐carotene; and (b) when oils were not treated with citric acid, only oils containing 20 ppm β‐carotene were more stable to light. Capillary gas chromatographic analysis showed that the addition of 1 to 20 ppm of β‐carotene significantly decreased formation of 2‐heptenal and 2,4‐decadienal in the absence or presence of citric acid. Determination of peroxide values showed the same trends as gas chromatographic analyses of volatiles. In the presence of 15 and 20 ppm β‐carotene, some off‐flavors, as well as poor ratings for color quality, were reported by panelists. Therefore, flavor deterioration initiated by light can be inhibited effectively in soybean oil, without affecting color quality, by addition of β‐carotene at concentrations from 5 to 10 ppm to oils treated with citric acid.
Gamma‐irradiation to inactivate thioglucosidase of crucifers
Authors: Lessman K. J. , McCaslin B. D.
Published: January 2007

The crucifers contain glucosinolates which through enzymatic hydrolysis give rise to toxicants that limit the use of oil‐free meal obtainable from this plant family. Seeds from three crucifers were used to test gamma irradiation to inactivate enzyme systems as a step toward detoxification. Seeds ofCrambe abyssinica Hochst (crambe), ground seeds ofSinapis alba L. (mustard), and seeds ofBrassica napus L. (rape) were subjected to gamma‐irradiation (6.25, 12.5, 25.0 and 50.4 Mrad) to inactivate thioglucosidase and/or destroy glucosinolates. Samples of ground seeds, their oil‐free meals, previously irradiated ground seeds and their oil‐free meals were assayed for glucose, a product of enzymatic hydrolysis of glucosinolates present in the crucifer seeds. The 50.4 Mrad exposure inactivated thioglucosidase but did not destroy glucosinolates. The fatty acid contents of extracted oils were affected. The amino acid profile of defatted crambe protein meal was affected, while that of white mustard was not.
Alkyl ethoxylates: An assessment of their oral safety alone and in mixtures
Authors: Zerkle Tanya B. , Ross Joseph F. , Domeyer Bruce E.
Published: January 2007

Some alkyl ethoxylates (AEs), nonionic surfactants which are widely used in industry and in household cleaning products, have been demonstrated to produce acute neuropharmacologic effects when sufficient systemic exposure is achieved. An investigative program was undertaken to characterize these effects and to evaluate the neuropharmacologic potential of some AEs with specific chainlengths, both commercially available materials and a pure homologue, following accidental oral exposure. Results show that even these AEs can be used safely in household cleaning products when their pharmacological properties are taken into consideration.

Intraperitoneal administration of aqueous solutions of AEs to rats resulted in a progressive and reversible syndrome of central nervous system excitation and depression (ataxia, loss of righting) that resembled the induction of and recovery from general anesthesia. Oral administration to rats and mice of aqueous solutions of AEs, alone or in combination with anionic surfactants and ethanol, at concentrations that approach or exceed the maximum expected in household products (10–25%), rarely induced general anesthesia and then only at very high dose volumes (10 ml/kg and above).

Based on these results and the fact that products containing the AEs evaluated usually produce emesis in humans, it is concluded that: (i) AE‐induced general anesthesia is not predicted to occur in humans following accidental oral exposure to products containing both the AEs and anionic surfactants, and (ii) general anesthetic effects in humans following accidental oral exposure to products containing fairly high levels of the specific AEs as the nonionic surfactant would be expected to occur only in cases of extremely high volumes of accidental ingestion (≥10 ml/kg).
A rapid, automated method for the determination ofcis andtrans content of fats and oils by fourier transform infrared spectroscopy
Authors: van de Voort F. R. , Ismail A. A. , Sedman J.
Published: January 2007

A rapid Fourier transform infrared (FTIR) method was developed to simultaneously determine percentcis andtrans content of edible fats and oils. A generalized, industrial sample‐handling platform/accessory was designed for handling both fats and oils and was incorporated into an FTIR spectrometer. The system was calibrated to predict thecis andtrans content of edible oils by using pure triglycerides as standards and partial least squares as the chemometric approach. The efficacy of the calibration was assessed by triglyceride standard addition, by mixing of oils with varyingcis/trans contents, and by analyzing fats and oils of known iodine value. Each of the approaches verified that the FTIR method measured thecis andtrans content in a reproducible (±0.7%) manner, with the measured accuracies being 1.5% for standard addition and 2.5% for the chemically analyzed samples. Comparisons also were made to the conventional American Oil Chemists’ Society (AOCS) method for the determination oftrans isomers by IR spectroscopy. The FTIR‐partial least squares approach worked well over a wide range oftrans contents, including those between 0 and 15%. The sample‐handling accessory designed for this application is robust, flexible, and easy to use, being particularly suited for quality‐control applications. In addition, the analysis was automated by programming the spectrometer in Visual Basic (Windows), to provide a simple, prompt‐based user interface and to allow an operator to carry outcis/trans analyses without any knowledge of FTIR spectroscopy. A typical analysis requires less than two minutes per sample. The derived calibration is transferable between instruments, eliminating the need for recalibration. The integrated analytical system provides a sound basis for the implementation of FTIR methods in place of a variety of AOCS wet chemical methods when analytical speed, cost, and environmental concerns are issues.
Wetting of fat crystals by triglyceride oil and water. 1. The effect of additives
Authors: Johansson Dorota , Bergenståhl Björn , Lundgren Eva
Published: January 2007

Wetting of fat crystals has been extensively examined in this work by contact angle (θ) measurements of fat crystal, oil, and water in three‐phase contact. Contact angle was measured in oil. The crystals were nonpolar and wetted by oil for a contact angle equal to 0°, and polar and wetted by water for an angle equal to 180°. Fat crystals are expected to contribute to the stability of margarine emulsions if they are preferentially wetted by the oil phase (0°<θ<90°), but result in instability if they are preferentially wetted by the water phase (90°<θ<180°). In the absence of oil and water additives, fat crystals in α and β' polymorphs were introduced to the oil/water interface from the oil side (contact angle θ ∼ 30°). β Polymorphs were completely wetted by oil (θ ≈ 0°). The contact angle for β' crystals decreased with increasing temperature and was slightly lower in butter oil than in soybean oil. Emulsifiers in the oil phase (lecithins, monoglycerides and their esters, ethoxylated emulsifiers) and surface‐active proteins in the water phase (milk proteins) made the crystals more polar (higher θ). Nonsurface‐active proteins, sugar, and citric acid had no significant effect, although concentrations of salt lowered θ. Contact angle increased with temperature for emulsifiers of limited solubility in the oil, e.g., saturated monoglyceride.
Lipid composition of ten edible seed species from North Vietnam
Authors: Imbs A. B. , Pham Long Quoc
Published: January 2007

The lipid composition and oil content of ten edible seed species from North Vietnam(Cassia tora, Ipomoea aquatica, Raphanus sativus, Citrullus lanatus, Cucumis melo, Cucurbita pepo, Luffa cylindrica, Phaseolus vulgaris, Vigna aurea, Sesamum orientale) have been investigated. The contents of hydrocarbon, triacylglycerol, free fatty acid, sterol, di‐ and monoglycerol, and polar lipid fractions have been determined with a thin‐layer chromatography (TLC)/flame‐ionization detection analyzer. Molecular species of hydrogenated triacylglycerols and the fatty acid composition of total lipids also have been analyzed by capillary gas‐liquid chromatography. The quantities of major phospholipid classes of four seed species(C. tora, I. aquatica, R. sativus, V. aurea) have been determined by two‐dimensional TLC and the spectrophotometrical phosphorus analysis. The fatty acid compositions of nonpolar and polar lipid fractions of these four species also have been analyzed.
Biological and physiological factors in soybeans
Authors: Rackis Joseph J.
Published: January 2007

There are limitations to which one is justified in drawing broad generalizations concerning the diverse biological and physiological effects of soy protein products. Nevertheless, there appear to be two distinct situations: (A.) Proper heat treatment exerts a beneficial effect upon the nutritive value of whole soybeans, full‐fat and defatted meal. Associated with proper heating is inactivation of trypsin inhibitor and other heat‐labile factors and conversion of raw refractory proteins to forms that are more readily digested. (B.) Moist heat also has a beneficial effect upon the nutritive value of soy protein isolates. However, a deficiency of certain essential nutrients and the interaction of phytic acid with protein, vitamins, and minerals during processing are the primary factors responsible for the poor nutritive value of soy isolates. Occasionally mineral deficiency symptoms do occur in animals fed soybean meal. It is a misnomer to refer to the growth‐inhibiting and pancreatic hypertrophic properties as a “toxic” effect since both properties are reversible. Modern analytical techniques should be used to reinvestigate the relationship between phytic acid and availability of minerals and vitamins in soy protein isolate diets. Research also is needed to determine more accurately vitamin and mineral contents of soy protein isolates and the availability of vitamins and minerals in soy protein concentrates. Breeding soybean varieties genetically deficient in antinutritional and nonflatulent factors does not appear promising. More research is needed to determine whether fermentation and enzyme processes can be used to prepare flatulent‐free soy products. Minor factors to be considered in assessing the nutritive value of soy products include a weak goitrogen present in soybeans, and a very low estrogenic activity.
Continuous slurry hydrogenation of soybean oil with copper‐chromite catalyst at high pressure
Authors: Koritala S. , Moulton K. J. , Friedrich J. P. , Frankel E. N. , Kwolek W. F.
Published: January 2007

Selective hydrogenation of soybean oil to reduce linolenic acid is accomplished better with copper than with nickel catalysts. However, the low activity of copper catalysts at low pressure and the high cost of batch equipment for high‐pressure hydrogenation has precluded their commercial use so far. To evaluate continuous systems as an alternative, soybean oil was hydrogenated in a 120 ft × 1/8 in. tubular reactor with copper catalyst. A series of hydrogenations were performed according to a statistical design by varying processing conditions: oil flow (0.5 L/hr, 1.0 L/hr and 2.0 L/hr), reaction temperature (180 C and 200 C), hydrogen pressure (1,100 psig and 4,500 psig) and catalyst concentration (0.5% and 1.0%). An iodine value (IV) drop of 8–43 units was observed in the products whereas selectivity varied between 7 and 9. Isomerization was comparable to that observed with a batch reactor. Analysis of variance for isomerization indicated interaction between catalyst concentration and hydrogen pressure and between catalyst concentration and temperature. The influence of pressure on linolenate selectivity was different for different temperatures and pressure. Hydrogenation rate was significantly affected by pressure, temperature and catalyst concentration.
Detection of cow milk admixture to buffalo milk
Authors: Farag R. S. , Hewedi M. M. , Abo‐Raya S. H. , Khalifa H. H.
Published: January 2007

A method has been devised that gives the distribution of various fatty acids of pure and adulterated buffalo milk with cow milk. Gas chromatography (GC) was used for the qualitative and quantitative determination of fatty acids of authentic buffalo milk, cow milk and buffalo milk adulterated with cow milk. The milk fat was separated by fractional crystallization at ‐20 C into 2 fractions, i.e., semisolid and mother liquor. The concentration of fatty acids in the mother liquor changed significantly for 14:0, 16:0 and 18:1 as adulteration levels were increased. The fatty acids of the semisolid fractions change in the proportion of 16:0, 18:0 and 18:1 when cow milk is mixed with buffalo milk. By applying simple regression equations for these acids, adulteration of buffalo milk with 5% cow milk could be distinguished.
Chia seeds as a source of natural lipid antioxidants
Authors: Taga M. Silvia , Miller E. E. , Pratt D. E.
Published: January 2007

Chia (Salvia sp) seeds were investigated as a source of natural lipid antioxidants. Methanolic and aqueous extracts of defatted chia seeds possessed potent antioxidant activity. Analysis of 2 batches of chia‐seed oils demonstrated marked difference in the fatty acid composition of the oils. In both batches, the oils had high concentrations of polyunsaturated fatty acids. The major antioxidant activity in the nonhydrolyzed extract was caused by flavonol glycosides, chlorogenic acid (7.1 × 10−4 mol/kg of seed) and caffeic acid (6.6 × 10−3 m/kg). Major antioxidants of the hydrolyzed extracts were flavonol aglycones/kaempferol (1.1 × 10−3 m/kg), quercetin (2.0 × 10−4 m/kg) and myricetin (3.1 × 10−3 m/kg); and caffeic acid (1.35 × 10−2 m/kg). Two methods were used to measure antioxidant activities. Both were based on measuring bleaching ofβ‐carotene in the coupled oxidation ofβ‐carotene and linoleic acid in the presence of added antioxidants.
Synthesis of sulfur heterocycles from α,β‐unsaturated carbonyl fatty acid esters
Authors: Mustafa Jamal , Ahmad M. S. , Rauf A. , Osman S. M.
Published: January 2007

Alkyl chain substituted oxathiolanes from allylic oxo are described. Reaction of methyl 4‐oxo‐trans‐2‐hexadecenoate (1) with β‐mercaptoethanol yields methyl 4‐oxathiolane‐trans‐2‐hexadecenoate (II), methyl 4‐oxathiolane‐2(3)‐(S‐β‐mercaptoethyl acetate) hexadecanoate (III) and methyl 4‐oxathiolane‐2(3)‐(S‐β‐mercaptoethanol)hexadecanoate (IV).
Stabilization of tocopherol by three components synergism involving tocopherol, phospholipid and amino compound
Authors: Ishikawa Y. , Sugiyama K. , Nakabayashi K.
Published: January 2007

The effects of minor‐component phospholipids, sterols, trimethylamine oxide (TMAO) and tri‐n‐octylamine (TOA) on the stabilization of γ‐tocopherol (γ‐Toc) were investigated during the autoxidation of methyl linoleate (ML). On autoxidation of lard containing γ‐Toc and TMAO, γ‐Toc was rapidly oxidized and decreased to the 50–60% level in the initial stage of reaction. After that, the total amounts of γ‐Toc and its reducing dimers, γ‐Toc diphenyl ether dimer, γ‐Toc biphenyl dimer (H), and γ‐Toc biphenyl dimer (L), formed from oxidized γ‐Toc, were maintained at a higher level for a longer time. These results indicate the presence of minor components contribution to the stability of γ‐Toc. Therefore, three‐component synergism involving γ‐Toc, TMAO and each phospholipid was tested using ML as substrate. Accordingly, phosphatidyl ethanolamine (PE), phosphatidyl serine (PS), phosphatidyl inositol and phosphatidic acid showed a marked synergistic effect: PS especially inhibited the oxidation of γ‐Toc. More than 0.02% of PE was found to keep a constant level of the residual amount of γ‐Toc and to retared the formation of γ‐Toc biphenyl dimers, which are perferential in the presence of TMAO. Phosphatidyl choline (PC), phosphatidyl glycerol and sterols did not show such an effect. However, PC synergized with TOA for stabilizing γ‐Toc in autoxidizing ML.
A comparison of high‐performance liquid chromatography and spectrophotometry to measure chlorophyll in canola seed and oil
Authors: Ward Kerry , Scarth Rachael , Daun J. K. , Thorsteinson C. T.
Published: January 2007

There are several methods available to measure chlorophyll in canola oil and seed, and these will not necessarily yield the same results and should not be used in terchangeably. Total chlorophyll was determined for samples of canola seed and commercial canola oil by recognized spectrophotometric methods and by high‐performance liquid chromatography (HPLC). The HPLC method, which summed all chlorophyll‐related pigments detected, found approximately 1.4 times more total chlorophyll per sample than did the spectrophotometric methods. The spectrophotometric methods are calibrated with only chlorophyll a and underestimate other chlorophyll pigments, which have lower extinction, coefficients and different absorption maxima. The HPLC method detects each pigment at its absorption maxima and applies the appropriate absorptivity factor. Care must be taken when comparing results obtained by different methods. There appears to be a need for a standardized method of chlorophyll pigment measurement by HPLC.
Improved lipase‐catalyzed incorporation of long‐chain fatty acids into medium‐chain triglycerides assisted by supercritical carbon dioxide extraction
Authors: Shishikura Akihiro , Fujimoto Kenshiro , Suzuki Teruhiko , Arai Kunio
Published: January 2007

Displacement of the equilibrium of the lipase‐catalyzed interesterification between medium‐chain triglyceride (MCT) and long‐chain polyunsaturated fatty acid was accomplished by the removal of by‐products with continuous supercritical carbon dioxide (SC−CO2) extraction at 60°C and 100 kg/cm2. The incorporation of eicosapentaenoic acid to MCT was appreciably improved by this method and was 1.3 times higher than that of the equilibrium state (47 wt%) that was obtained in a closed system. The immobilizedMucor miehei lipase was stable for more than 180 h in SC−CO2 at 60°C and 100 kg/cm2.
Distribution of the major fatty acids of human milk betweensn‐2 andsn‐1,3 positions of triacylglycerols
Authors: Kallio Heikki , Rua Philippe
Published: January 2007

Human milk triacylgycerols (TAG) were analyzed by tandem mass spectrometry. The SIMPLEX method and a simple linear model were used to interpret the distribution of fatty acids between thesn‐2 andsn‐1,3 positions in 24 major molecular weight groups of TAG. The number of regio‐isomeric pairs of TAG varied between 3 and 18 in each of these groups. Hexadecanoic (16∶0), tetradecanoic (14∶0) and dodecanoic acids (12∶0) typically occupied thesn‐2 position in TAG containing less than 54 acyl carbons, whereas long‐chain C18 and C20 acids were predominantly located at the primary positions. The positions of the three fatty acids within a TAG molecule were shown to depend on the fatty acid combination. The maximum of 12∶0 in thesn‐2 position appeared at acyl carbon number (ACN) 48, the maxima of 14∶0 were at ACN 44 and ACN 50, and for 16∶0 at ACN 46 and 52.
Effects of the ethylene oxide distribution on nonionic surfactant properties
Authors: Dillan K. W.
Published: January 2007

Detergent‐range primary alcohols are readily converted into nonionic surfactants by reaction with ethylene oxide. Optimum performance properties for these surfactants generally are attained by varying the number of moles of ethylene oxide reacted with each mole of alcohol or by altering the structure of the primary alcohol. However, variations in the ethoxylate‐adduct distribution also affect surfactant properties in such a way that products with relatively narrow distributions possess features which are highly desirable in many household and industrial applications. For a given cloud point narrow‐range ethoxylates have lower molecular weights and therefore lower pour points than broad‐range surfactants. Because narrow‐range ethoxylates contain less unreacted alcohol and other water‐insoluble species, they are capable of forming aqueous solutions with much lower cloud points than their broad‐range counterparts. Aqueous solutions of narrow‐range products have lower viscosities, exhibit lower gel temperatures and remain fluid over a wider concentration range than solutions of broad‐range surfactans. While the foams obtained with narrow‐range surfactants in the Ross‐Miles test are higher initially, they are less stable than those produced by conventional nonionic surfactants. Draves wetting data show that narrow‐range products wet cotton substrates more efficiently than normal‐distribution materials. Narrow‐range ethoxylates exhibit higher aqueous surface tension and higher polyester adhesion tension values than their broad‐range counterparts. In addition, narrow‐range surfactants reduce the interfacial tension against paraffin oil more efficiently and more effectively than broad‐range products. These results, along with laboratory detergency data, suggest that the use of narrow‐range ethoxylates may lead to cleaning systems with improved performance and/or physical properties.
Homogeneous catalytic hydrogenation of soybean oil: Palladium acetylacetonate
Authors: Koritala S.
Published: January 2007

Soybean oil was hydrogenated with palladium acetylacetonate at 60–170 C, 150 psi hydrogen and 1–60 ppm palladium. The best linolenate selectivity (KLe/KLo=3.5−3.7) was found at 80–120 C. At 120 C palladium acetylacetonate hydrogenated faster than the heterogeneous Pd‐on‐carbon catalyst.Trans isomerization with the homogeneous catalyst was much higher compared to Pd‐on‐carbon catalyst. The low activity of the palladium complex at low temperatures was improved with the addition of triethylaluminum. Among other metal acetylacetonates tested only nickel and chromium were mildly active, whereas cobalt and copper were devoid of catalyst activity.
Derivatization of keto fatty acids: VI. Synthesis, oxidation and mass spectrometry of dithiolanes
Authors: Khan Mushfiquddin , Hashmi Mazzaz , Ahmad F. , Osman S. M.
Published: January 2007

The synthesis of alkyl chain‐substituted dithiolanes, bisdithiolane and disulfolanes from oxo acids and their decomposition to original oxo acids are described. Reactions of ethanedithiol with 2 oxo esters, methyl 10‐oxoundecanoate and methyl 12‐oxooctadecanoate, give excellent yield of the corresponding dithiolanes, which are oxidized to the respective disulfolanes by m‐chloroperbenzoic acid (m‐CPBA). A similar reaction of ethanedithiol with methyl 9,10‐dioxooctadecanoate affords bisdithiolane. Retroreactions of the dithiolanes and bisdithiolanes under acidic conditions and of disulfolanes under alkaline conditions yield the parent oxo acids. The structures of the individual reaction products have been established from analytical and spectral data and confirmed by a study of their mass spectra.
Dry bean tannins: A review of nutritional implications
Authors: Reddy N. R. , Pierson M. D. , Sathe S. K. , Salunkhe D. K.
Published: January 2007

Tannins are one of several antinutritional factors present in dry beans and are located mainly in the seed coat or testa. The tannin content of dry beans ranges from 0.0 to 2.0% depending on the bean species and color of the seed coat. Many high tannin bean varieties are of lower nutritional quality than low tannin varieties of beans. Naturally occurring food legume tannins are reported to interact with proteins (both enzyme and nonenzyme proteins) to form tannin‐protein complexes resulting in inactivation of digestive enzymes and protein insolubility. Both in vitro and in vivo studies indicate that bean tannins decrease protein digestibility, either by inactivating digestive enzymes or by reducing the susceptibility of the substrate proteins after forming complexes with tannins and absorbed ionizable iron. Other deleterious effects of tannins include a lowered feed efficiency and growth depression in experimental animals. The antinutritional activity of bean tannins can be reduced by processing (1 or a combination of 2 or more methods), for example dehulling, soaking, cooking and germination. Genetic selection also may help in breeding varieties low in tannins. Potential chemical treatments such as use of tannin complexing agents are discussed.
Fruit oil composition and characteristics of two spurge species of Turkish origin
Authors: Aksoy H. Ayse , Yavasoglu N. , Karaosmanoglu F. , Civelekoglu H.
Published: January 2007

Content and characteristics of the triglyceride fruit oils of two spurge (Euphorbia L.) subspecies, namelyE. glaerosa Pallas ex Bieb. (var.lasiocarpa Boiss.) andE. niciciana Borbas ex Novak, were investigated. For both taxa, oil content of the capsules enclosing the seeds ranged between 15.7 and 16.4% on dry basis, while the decapsulated seeds contained 33.0–34.0% oil, also on dry basis. The average saponification, iodine and acid values were 192, 190 and 6.0, respectively; linolenic acid was detected as the major constituent fatty acid. Consequently, these seed oils are characterized as typical drying oils.
A methodology study to evaluate quality of soybeans stored at different moisture levels
Authors: Frankel E. N. , Nash A. M. , Snyder J. M.
Published: January 2007

The quality of soybeans and oil extracted from seeds stored at different moisture contents was evaluated by static headspace gas chromatography, near‐infrared spectrometry, fluorescence measurements, and silicic acid chromatography. Headspace gas chromatographic analysis of both ground beans and crude oils provided a sensitive measure of oxidative deterioration based on hexanal and total volatiles. Near‐infrared analyses at 2260 nm showed a correlation coefficient of 0.864 with titratable free fatty acids. Fluorescence measurements on chloroform‐methanol extracts were much less sensitive and showed an increase only in the most damaged samples. Silicic acid chromatography of crude oils showed a significant decrease of polar lipids and increase of less polar lipids with storage at high moisture levels, in agreement with the decrease in phosphorus observed. Among the methods tested, headspace gas chromatography is most sensitive to evaluate oxidative deterioration, and near‐infrared analysis is most suitable and rapid to evaluate hydrolytic deterioration in stored soybeans. This methodology can be used to evaluate factors affecting the food quality of soybeans for domestic and foreign markets.
Monoglyceride analysis with reversed phase HPLC
Authors: Takano Satoshi , Kondoh Yukihiro
Published: January 2007

A simple, convenient method for the simultaneous determination of the homologous distribution and ratio of positional isomers of monoglycerides in commercial products has been developed. Monoglycerides were analyzed with reversed phase HPLC using the glyceride‐selective post‐column reactor detector (GS‐PCRD). The GS‐PCRD indicated molar responsibility to all monoglycerides up to monostearin. It can, for example, detect 0.07 nmol of 1‐monolaurin and give a linear working curve between 0.18–80.3 nmol of 1‐monolaurin. Furthermore, monoglycerides in commercial margarines could be selectively detected and quantitatively determined without any pretreatment. Therefore, the proposed method should be applicable to the analysis of monoglycerides in various commercial products.
Heat treatment of vegetable oils I. Isolation of the cyclic fatty acid monomers from heated sunflower and linseed oils
Authors: Sebedio J. L. , Prevost J. , Grandgirard A.
Published: January 2007

Linseed and sunflower oils were heated at 275 C for 12 hr under nitrogen. The sunflower oil was also heated in a commercial fryer at 200 C for 48 hr using a 2‐hr daily cycle. The cyclic fatty acid monomers (CFAM) formed during the heat treatment of the linseed oil were isolated by a combination of saponification, esterification, column chromatography on silicic acid and urea fractionation. The isolated CFAM fraction was 99% pure, the balance being some 12:2ω6. Another step was necessary to isolate the CFAM from heated sunflower oils. The urea adduct fractionation resulted in the isolation of a nonurea adduct fraction which contained a mixture of CFAM and 18:2ω6. These were further separated using high performance liquid chromatography (HPLC) on a C18 reverse phase column. Each fraction was analyzed by gas liquid chromatography and hydrogenated to determine the content of the C18 straight chain fatty acids.
Comparative nutritional value for amino acids, oligopeptides and soybean protein
Authors: Arai Soichi , Kimura Hiroko
Published: January 2007

In recent years our view on the absorption of protein digestion products has undergone a radical change. We now believe that intralumen hydrolysis of intake proteins to free amino acids is only partial. It has thus been hypothesized that partial protein hydrolysates or oligopeptide mixtures are nutritionally superior to corresponding amino acid mixtures. With this consideration for a background, we developed a sophisticated technique of protease‐catalyzed modification of soy protein to produce enzymatically modified proteins (EMP) having different levels of covalently attached methionine. We also carried out feeding tests with protein‐malnourished rats, with the result that for their recovery from a state of malnutrition, an EMP containing peptide‐bound methionine at 3% was significantly more effective than the corresponding amino acid mixture and even the soy protein itself. Discussions stress the importance of applying such a technique to production of an oligopeptide rather than a free amino acid nitrogen source as a foodstuff for therapeutic use.
β‐Carotene adsorption on acid‐activated montmorillonite
Authors: Sarier N. , Güler Ç.
Published: January 2007

The adsorption of β‐carotene from solution in benzene on acid‐activated Canakkale montmorillonite of Turkey has been investigated. The adsorption isotherm had two steps. The first step was of the Langmuir type, and the isosteric heat of adsorption corresponding to this step was equal to −193.514 kJ/mol. The decrease in the total number of acid sites of the clay surface was determined to be 0.45×10−4 mol/g clay by nonaqueous titration with diethylamine. The phenomenon seems to be mainly a chemisorption stemming from the interaction of β‐carotene with acid sites. Also, the activated clay acts as an oxidation catalyst on the β‐carotene left in the solution.