bluuebunny/crossref_metadata_2025 huggingface dataset:
Indoor and outdoor submicrometer particles: Exposure and epidemiologic relevance (“the 3 indoor Ls”)
Authors: Franck Ulrich , Tuch Thomas , Manjarrez Maria , Wiedensohler Alfred , Herbarth Olf
Published: November 2006

Airborne particles represent a very important pollutant with respect to healthy housing conditions. The snag is that in lack of indoor data epidemiological studies focusing on submicron and ultrafine (<100 nm in diameter) particles are usually forced to use outdoor particle concentrations only. On the other hand it is known that people spend most of their time indoors. The aim of this paper is therefore to give a short comprehensive overview of the indoor/outdoor problem with regard to submicron and ultrafine particles, investigating how indoor particle size distributions correlate with outdoor concentrations in the absence of significant indoor sources. In the absence of a major indoor source, total indoor particle number concentrations were always lower than outdoor concentrations. The highest ratios between indoor and outdoor concentrations tend to correlate with lower rather than higher total outdoor particle number concentrations. Concentration ratios depend on particle size. Time lags of the correlation coefficients between the concentrations of indoor and outdoor particles of different diameters have been determined to assess the time the particles need to enter the indoor site through closed modern‐type windows. Typical lag times of 0.5–3 h between somewhat smaller indoor particles and somewhat larger outdoor particles have been observed. To assess the resulting particle burden for humans, a suitably weighted average emphasizing indoor aerosol particles must be used. To classify the health effects of particles of different diameters, different decreases of particle number concentrations depending on the particle sizes must be taken into account if indoor concentrations cannot be measured and outdoor concentrations are used in place of indoor measurements. In urban areas, ultrafine particles originate primarily from rapidly increasing traffic, which is the dominating source at many urban sites. The influence of traffic on outdoor and indoor concentrations is therefore of special interest. © 2006 Wiley Periodicals, Inc. Environ Toxicol 21: 606–613, 2006.
Functional properties of wild yam (Dioscorea spp.) starches
Authors: Sahoré DA , Amani NG , Kamenan A
Published: November 2006

The starches of the wild yam species Dioscorea praehensilis, D. hirtiflora, D. burkilliana, D. togoensis, D. dumetorum and D. bulbifera (tuber and bulbil) were isolated, and their paste viscosity and clarity, iodine binding and syneresis were investigated. Copyright © 2006 John Wiley & Sons, Ltd
Exact solutions for the unsteady free convection flows on a porous plate with time‐dependent heating
Authors: Toki C.J. , Tokis J.N.
Published: November 2006

The unsteady free‐convection flows of a viscous and incompressible fluid near a porous infinite vertical plate (or wall) are investigated under an arbitrary time‐dependent heating of the plate. Exact solutions of this problem are obtained with the help of Laplace transform technique, when the plate is moving with an arbitrary time‐dependent velocity and for special cases of the impulsive and the accelerated heating effects. These solutions are given in closed form for arbitrary Prandtl number of the fluid and for the thermal porous wall with or without suction or injection. The particular cases of the thermal plumes which are responsible for atmospheric pollution are also discussed.
Wax diffusivity under given thermal gradient: a mathematical model
Authors: Correra S. , Fasano A. , Fusi L. , Primicerio M. , Rosso F.
Published: November 2006

In this paper we describe how to obtain wax diffusivity and solubility in a saturated crude oil using the measurements of solid wax deposit in the experimental apparatus known as cold finger. Assuming that migration of dissolved wax is primarily driven by thermal gradients, a mathematical model is derived relating the deposit growth rate to the above mentioned quantities. We investigate the case in which the oil is not agitated. Comparisons with available experimental data are performed and possible sources of errors are discussed.
Aqueous enzymatic extraction of coconut oil
Authors: Che Man Y. B. , Suhardiyono  , Asbi A. B. , Azudin M. N. , Wei L. S.
Published: November 2006

Aqueous extraction of coconut oil with various enzymes was investigated. Several enzyme preparations (cellulase, polygalacturonase, protease, and α‐amylase) were used at different concentrations, pH, and temperature values to enhance oil extraction. After the oil had been released by the enzyme reaction, it was separated by centrifugation. The results showed that an enzyme mixture at 1% (w/w) each of cellulase, α‐amylase, polygalacturonase, and protease at pH 7.0 and an extraction temperature of 60°C represented the most effective extraction conditions with an oil yield of 73.8%. Quality characteristics of the oil were as follows: moisture content, 0.11%; free fatty acid, 0.051%; peroxide value, 0.016 meq oxygen/kg; anisidine value, 0.026; iodine value, 8.3; saponification value, 260; and color, 0.6 (Y+5R). This technique for recovering oil from fresh coconut meat with enzymes is a significant improvement in both oil yield and quality over the traditional wet process.
Tempering method for chocolate containing milk‐fat fractions
Authors: Reddy S. Yella , Full N. , Dimick P. S. , Ziegler G. R.
Published: November 2006

Anhydrous milk fat (AMF) was fractionated by a two‐stage dry fractionation process to produce three fractions—high‐(HMF), middle‐(MMF), and low‐melting (LMF). The effect of replacing 12.2–40% by weight of cocoa butter with these fractions on the tempering profile of milk chocolate was studied. Degree of temper was evaluated by differential scanning calorimetry, and expressed as the ratio of enthalpies of melting for higher‐stability polymorphs to those of lesser stability. The degree of temper was dependent on the crystallization time and temperature, and the type and quantity of milk‐fat fraction in the formulation. Chocolates containing AMF or its fractions in concentrations of up to 20 wt% (total fat basis) were tempered after a conventional thermocycling tempering process (50°C/30 min, 27.7°C/4 min, 31°C/2 min) to obtain products with good contraction and mold release properties. For those milk chocolate formulations that did not temper by the conventional method and resulted in poor contraction and mold release, a new tempering protocol was developed. Lower crystallization temperatures and/or longer holding times were required at concentrations of AMF, MMF, or LMF above 20%. Chocolate containing HMF required slightly higher crystallization temperatures because of high viscosity. Chocolates containing up to 35% HMF and up to 40% of the total weight of fat in the chocolate of AMF, MMF, and LMF were successfully tempered by adjusting crystallization time and temperature.
Soybean seed composition under high day and night growth temperatures
Authors: Gibson L. R. , Mullen R. E.
Published: November 2006

High diurnal temperatures often affect development of soybean [Glycine max (L.) Merr.], but little is known about the relative influence of high day and night temperatures on the chemical composition of the seed. This study was conducted to determine the effects of combinations of high day and night temperatures during flowering and pod set (R1–R5), seed fill and maturation (R5–R8), and continuously during the reproductive period (R1–R8) on soybean seed oil, protein, and fatty acid composition. Day/night temperatures of 30/20, 30/30, 35/20, and 35/30°C were imposed on the soybean cultivar Gnome 85 in growth chambers. The day/night temperature combinations during R1–R5 had little effect on the oil and protein concentration and the fatty acid composition of seed produced. As mean daily temperature increased from 25 (30/20) to 33 (35/30)°C during R5–R8 and 25 (30/20) to 33 (35/30)°C during R1–R8, and oil concentration decreased and protein concentration increased. Increased day temperature during R5–R8 and R1–R8, averaged across the two night temperatures, increased oleic acid and decreased linoleic and linolenic acids. When night temperature was increased at 30°C day temperature during R5–R8 and R1–R8, oleic acid decreased and linoleic acid increased. When night temperature was increased at 35°C day temperature during R1–R8, oleic acid increased, and linoleic and linolenic acids decreased. These results indicate the importance of high day and night temperatures during seed fill and maturation in the oil, protein, and fatty acid composition of soybean seed.
Crystallization characteristics of methyl tallowate and its blends with ethanol and diesel fuel
Authors: Hanna Milford A. , Ali Yusuf , Cuppett S. L. , Zheng Danian
Published: November 2006

Methyl tallowate was prepared from edible beef tallow via transesterification, and was blended with ethanol and/or No.2 diesel fuel in different ratios. Crystallization characteristics of methyl tallowate and its blends were studied at temperatures ranging from 22 to −16°C. Blending ethanol with methyl tallowate reduced crystal formation at all temperatures. As the temperature of the blends was reduced from 22 to 0°C, there was no effect on crystal formation of saturated vs. unsaturated fatty acids. Below 0°C, the saturated fatty acids crystallized at a much faster rate than the unsaturated fatty acids.
Antioxidant effects of flavonoids ofAnthriscus sylvestris in lard
Authors: Milovanovic M. , Picuric‐Jovanovic K. , Vucelic‐Radovic B. , Vrbaski Z.
Published: November 2006

Ethanol/water (7∶3) extracts of the plant speciesAnthriscus sylvestris possess antioxidant activity. Separation and identification of antioxidant components by thin‐layer and column chromatography and spectral analysis demonstrated that quercetin and apigenin appeared to be the main flavonoid species inAnthriscus sylvestris. Rutin was one of the major quercetin glycosides. Structures of the isolated compounds were determined by infrared and1H nuclear magnetic resonance spectroscopies. Ethanolic extract (70%) ofA. sylvestris showed concentration‐dependent, strong antioxidant activity as determined by the Schaal Oven test of lard at 60°C. Rancimat analysis at 100°C showed that the antioxidant activity of 70% ethanolic extract ofA. sylvestris was superior to quercetin, apigenin, or a tocopherol mixture.
Quantitative Fourier transform infrared analysis for anisidine value and aldehydes in thermally stressed oils
Authors: Dubois J. , van de Voort F. R. , Sedman J. , Ismail A. A. , Ramaswamy H. R.
Published: November 2006

A Fourier transform infrared (FTIR) transmission‐based spectroscopic method was investigated for the simultaneous monitoring of aldehyde formation and the determination of anisidine value (AV) in thermally stressed oils. Synthetic calibration standards were prepared by adding known amounts of hexanal,t‐2‐hexenal andt,t‐2,4‐decadienal to canola oil (these compounds considered representative of aldehydic compounds formed during oxidation) plus random amounts of other compounds representative of oxidation by‐products. The standards were analyzed for their chemical AV. With the partial least squares (PLS) technique, an FTIR spectrometer was calibrated to predict both the concentrations of individual aldehyde types and AV, with the individual aldehyde contributions being related to the chemical AV by multiple linear regression to derive “apparent” AV values. The predictive capability of the PLS calibrations was assessed by analyzing canola oils that were thermally stressed at 120, 155, and 200°C. The apparent AV, predicted for these samples, matched the chemical AV values within ±1.65 AV units. A PLS calibration also was derived by using thermally stressed samples as calibration standards. This approach provided similar predictive accuracy as the use of synthetic calibration standards. As such, quantitative determination of AV by FTIR spectroscopy was shown to be feasible, and the synthetic calibration approach provided additional information on the aldehyde types present in a sample and allowed the use of a simple gravimetric approach for calibrating an FTIR spectrometer. This study provides the basis for the development of a rapid, automated FTIR method for the direct analysis for AV of thermally stressed fats and oils in their neat form without the use of chemical reagents. The implementation of such a method as a quality control tool would eliminate the use and disposal of hazardous solvents and reagents, required by the conventional chemical method, and drastically reduce analysis time (∼2 min/sample). Possible applications include monitoring of the oxidative state of frying oils or evaluation of oxidative stability of biodegradable lubricants.
Miscella refining test method for the determination of cottonseed oil color
Authors: Wan P. J. , Pakarinen D. R. , Hron R. J.
Published: November 2006

Most of the cottonseed oil mills in the United States have already converted to expander solvent extraction and miscella refining. This practice permits mills to produce and market a consistently light‐colored, prime bleachable summer yellow cottonseed oil at reduced cost and refining loss. A laboratory‐scale miscella refining test was developed to asses the oil quality in terms of its color. The test involves the addition of 3 parts oleic acid per 100 parts of crude oil in the miscella followed by refining with 2.5 parts NaOH when crude oil contains less than 4.5% free fatty acid (FFA). When crude oil contains FFA between 4.5 and 7.5%, no oleic acid is added prior to refining with 2.5 parts NaOH. When crude oil contains FFA higher than 7.5%, no oleic acid is added and the caustic addition table in American Oil Chemists' Society Method Ca 9a‐52 is followed. The test was conducted at room temperature and gave reproducible colors comparable to commercially refined oils.
Assessment of potential prooxidant and antioxidant actions
Authors: Aruoma Okezie I.
Published: November 2006

Suggestions that oxidative stress plays a role in human diseases have led to the proposal that health might be improved by increased dietary intake of antioxidants. Plant‐derived antioxidants, such as flavonoids or rosemary extracts, are increasingly proposed as important dietary antioxidant factors, and foods rich in antioxidants are also receiving attention. Before widescale usage of natural and synthetic antioxidants can be suggested, it is necessary to establish the properties of such molecules. Assays for characterizing the potential prooxidant/antioxidant actions of food additives, antioxidant supplements, antioxidant drug molecules, and nutrient components have been developed for this purpose.
The Freundlich isotherm in studying adsorption in oil processing
Authors: Proctor A. , Toro‐Vazquez J. F.
Published: November 2006

The objective of this review is to discuss the history of the use of the Freundlich isotherm in investigating adsorption processing of vegetable oils and to evaluate its current value in adsorption studies. The Freundlich isotherm was originally developed to explain the adsorption of a single solute from solution. However, a similar adsorption pattern has been observed when studying a more complex system of adsorption of vegetable oil pigments onto bleaching clay during commercial bleaching of vegetable oils. The Freundlich isotherm has been useful for decades in finding the commercial value of adsorbents as long as a narrow experimental interval of adsorbate is used. More recent studies have shown that a complex series of interactions controls the adsorption process. While the isotherm summarizes these interactions, investigating them is vital to understand the physicochemical factors involved during adsorption. Statistical modeling and spectroscopy are useful in understanding the vegetable oil bleaching/refining process as a multiple‐component adsorption system.
The processing of new oilseed crops—An economic evaluation
Authors: Cuperus F. Petrus , Boswinkel Gerard , Derksen Johannes T. P.
Published: November 2006

The economics of pilot‐ to large‐scale processing of the new oilssed cropsCrambe abyssinica, Euphorbia lagascae, andDimorphotheca pluvialis into oil, fatty acids, or esters were estimated. It was found that the processing costs forCrambe seed to oil is in the same range as that for rapeseed (≈0.5 U.S. $/kg). Production of fatty acid esters from vernolic and dimorphecolic acids requires some special downstream processing operations that result in processing costs of about 1 U.S. $/kg ester. Good‐qualityDimorphotheca oil is much more difficult to obtain and requires supercritical carbon dioxide extraction. Processing costs can be as high as 4 U.S. $/kg oil.
Hexane sorption in oilseed meals
Authors: Cardarelli D. A. , Crapiste G. H.
Published: November 2006

Sorptional equilibrium of hexane in oilseed meals was studied as a function of temperature, solvent activity, and oil content. A dynamic technique was implemented based on gravimetric measurements with a Cahn electrobalance. Sorption and desorption isotherms of hexane in sunflower and soybean meals were determined at atmospheric pressure in the range 50 to 95°C. The equilibrium was reached faster during the adsorption process and at high hexane activities. The final equilibrium was not influenced by particle size and sample geometry. Hexane sorption is strongly dependent on temperature, meal composition and oil content, and the effect of hysteresis is negligible. Hexane is mainly retained by adsorption on the cell structure, absorption in the residual oil, and capillary condensation in the meal pores. Experimental equilibrium data were fitted to the GAB equation, and the parameters were determined by nonlinear regression analysis. This model represents satisfactorily the sorption behavior in a wide range of conditions.
Determination of sterols by capillary column gas chromatography. Differentiation among different types of olive oil: Virgin, refined, and solvent‐extracted
Authors: de Blas Oroncio Jiménez , del Valle González Amando
Published: November 2006

Compositional analysis of the sterol fraction of olive oil can be used to assess the degree of purity of the oil and the absence of admixture with other plant oils. This determination also permits characterization of the type of olive oil in question: virgin, refined, or solvent‐extracted. In the present work, 130 samples of olive oil were analyzed, the sterol fractions were separated from the unsaponifiable fraction by silica gel plate chromatography, and later they were analyzed as the trimethylsilyl ether derivatives by capillary column gas chromatography. From the results obtained, it was concluded that this methodology is able to differentiate among virgin, refined, and solvent‐extracted olive oils. Stigmasterol, clerosterol, Δ5‐avenasterol, Δ7‐stigmasterol, and Δ7‐avenasterol permit the differentiation of the three types of oil from one another. Campesterol, Δ5, 23‐stigmastadienol, β‐sitosterol, and Δ5,24‐stigmastadienol permit the differentiation of only two oils from each other but confirm the conclusions obtained for other sterols. Correlations between the different sterols of virgin, refined, and solven‐extracted olive oil also have been obtained.
Rapid and complete extraction of free fatty acids from oilseeds for acid value determination
Authors: Berezin O. Yu. , Tur'yan Ya. I. , Kuselman I. , Shenhar A.
Published: November 2006

The rapidity and uncertainty of the acid value determination in oilseeds are defined by the rate and completeness of the free fatty acid extraction. The strategy of reagent development for extraction has been discussed, and a set of reagents that provide rapid and complete extraction has been obtained. The set consists of two reagents. Reagent A contains triethanolamine in a mixture of water, isopropanol, and heptane. Reagent B contains a strong acid and inorganic salt in water. Reagent A allows the carrying out of rapid (1–2 min) solid‐liquid extraction of the free fatty acids and some other acids from oilseeds. Reagent B provides the separation of the free fatty acids only into the heptane phase (∼5 min), which can be used directly for the free fatty acid determination. Two techniques for this determination have been applied: pH‐metric and titrimetric. The advantages of the proposed set of reagents are described.
Physicochemical characteristics of liposomes formed with internal wool lipids
Authors: Coderch L. , de la Maza A. , Pinazo A. , Parra J. L.
Published: November 2006

The bilayer‐forming capability of internal wool lipids and their physicochemical properties were studied in an attempt to enhance our understanding of the lipid structure, present in wool and other keratinized tissues. Internal wool lipids were extracted and analyzed, and the mixture obtained [sterol esters (10%), free fatty acids (24%), sterols (11%), ceramides (46%), and cholesteryl sulfate (9%)] was shown to form stable liposomes. A phase‐transition temperature of 60°C was obtained from nuclear magnetic resonance spectra for this lipid mixture. The spontaneous permeability of these vesicles was lower than that of phosphatidylcholine liposomes but slightly higher than that of the vesicles formed with lipids extracted from other keratinized tissues with higher amounts of cholesterol. The transmission electron micrographs showed large vesicular aggregates of approximately 300 nm, which seem to be made up of smaller structures of approximately 20 nm in size. This particular structure could account for the large diameters and small internal volumes found by dynamic light‐scattering and spectrofluorometric measurements.
Separation and identification of ximenynic acid isomers in the seed oil ofSantalum spicatum R.Br. as their 4,4‐dimethyloxazoline derivatives
Authors: Liu Yandi D. , Longmore Robert B. , Fox John E. D.
Published: November 2006

The seed oil ofSantalum spicatum contains a significant amount of ximenynic acid,trans‐11‐octadecen‐9‐ynoic acid, a long‐chain acetylenic fatty acid, as a major component (34%). The identity oftrans‐ximenynic acid was confirmed after isolation by ultraviolet, infrared, and nuclear magnetic resonance (NMR) (1H‐ and13C‐) spectroscopy and by gas chromatography/mass spectrometry (GC/MS). Thecis isomer of ximenynic acid was also found (<1%) in some samples. Thecis andtrans isomers were characterized by GC/MS comparison of their methyl esters and 4,4‐dimethyloxazoline derivatives.
Applications of phase‐transfer catalytic reactions to fatty acids and their derivatives: Present state and future potential
Authors: Urata Kouichi , Takaishi Naotake
Published: November 2006

Phase‐transfer catalysts (PTC), which accelerate reactions between liquid(organic)‐liquid(water) and liquidsolid heterogeneous states, have been investigated and developed. Several processes with PTC have succeeded in industrial processes involving fatty acids and their derivatives. For example, preparation of fatty alkyl glycidyl ethers, from which fatty alkyl glyceryl ethers and their derivatives can be obtained, has been carried out with PTC. However, some problems remain to be solved. For example, preparation of the fatty alkyl glycidyl ether by a PTC reaction was considered, but typical problems to be solved included: (i) how to reuse or recover the catalysts; (ii) how to control the heterogeneous reaction without obstacles to produce useful chemical materials; (iii) how to satisfy the environmental requirements for the catalysts; and (iv) are there more effective catalysts? We address these problems based on our own experiences with phase‐transfer catalytic Williamson ether syntheses of fatty alkyl glycidyl ethers. Moreover, we describe recent developments in phase‐transfer catalytic reactions related to oleochemistry, such as transition metal‐catalyzed reactions of long‐chain olefins in liquid(organic)‐liquid(water) or liquid‐solid heterogeneous states. Based on these results, we have considered the potential of PTC as a synthetic tool in oleochemistry.
Effect of homolog distribution on the toxicity of alcohol ethoxylates
Authors: García M. T. , Ribosa I. , Leal J. Sánchez , Hreczuch W.
Published: November 2006

Previous work established a high correlation between the potential environmental toxicity of oxyethylenated nonionic surfactants and the average degree of ethoxylation. For this reason, it was considered of interest to determine whether a narrow‐ or broad‐range homolog distribution of polydisperse commercial alcohol ethoxylates would influence toxicity. Ethoxylated fatty alcohols, both linear and branched, were synthesized with sodium hydroxide or an unconventional calcium‐based catalyst. Toxicity tests were run onDaphnia magna and luminescent marine bacteria. Toxicity of ethoxylated alcohols as a function of type of ethoxylate homolog distribution (narrow or broad) and average degree of polyaddition is analogous for both test species. However, narrow‐range ethoxylates show lower toxicity values than conventional ethoxylates. Differences in toxicity values between broad‐ and narrow‐range ethoxylates depend on the degree of ethoxylation.
Surface‐active properties of novel cationic surfactants with two alkyl chains and two ammonio groups
Authors: Kim Tae‐Seong , Kida Toshiyuki , Nakatsuji Yohji , Hirao Toshikazu , Ikeda Isao
Published: November 2006

A series ofbis‐quaternary ammonium salts was easily prepared by the reaction of a long‐chaintert‐alkylamine with epichlorohydrin, and their surface‐active properties were measured. The prepared amphipathic compounds had good water solubility and showed characteristic surface‐active properties, particularly, extremely excellent foaming ability and foam stability for some specific compounds, such as the compound with a dodecyl and a tetradecyl group as the lipophilic chains. Their critical micelle concentration, which decreased with increased alkyl chainlength, is two orders of magnitude lower compared with the conventionalmono‐quaternary ammonium salts. In comparison with surface‐active properties ofbis‐quaternary ammonium salts, prepared from various organic dichlorides, there are little differences based on the kind of connecting group in the surface‐active properties except for foaming.
Biodegradability and aquatic toxicity of glycoside surfactants and a nonionic alcohol ethoxylate
Authors: Madsen Torben , Petersen Gitte , Seierø Connie , Tørsløv Jens
Published: November 2006

The environmental properties of three glycoside surfactants and one alcohol ethoxylate were examined by standardized laboratory methods. All of the surfactants biodegraded extensively in aerobic screening tests and may be assumed to approach 100% removal in aerobic wastewater treatment plants, except in cases of high loadings or otherwise exceptional conditions. Anaerobic biodegradability tests showed that an ethyl glycoside monoester (EGE) and a linear alkyl polyglycoside (APG) were both mineralized (>70%) under methanogenic conditions. In contrast, a branched APG resisted anaerobic degradation, while the alcohol ethoxylate was partially mineralized by anaerobic bacteria. The EGE surfactant was most rapidly mineralized in aerobic and anaerobic biodegradability tests. None of the surfactants inhibited respiration in activated sludge at the highest concentration tested (200 mg/L). Tests with aquatic organisms showed increasing toxicity in the following order: branched APG<EGE<linear APG<alcohol ethoxylate. Negligible aquatic toxicity was observed for the branched APG, while the alcohol ethoxylate was highly toxic to examined organisms. This evaluation demonstrates that considerable variation in biodegradability and toxicity responses can be seen within structurally related glucose‐based surfactants.
Effects of branching upon some surfactant properties of sulfated alcohols
Authors: O'Lenick Anthony J. , Parkinson Jeffrey K.
Published: November 2006

A study was undertaken to determine the surfactant properties of various sulfated alcohols. Most notably, the Krafft point and the ability to emulsify decane were studied. A series of sulfated Guerbet alcohol and Guerbet alcohol alkoxylate sulfates with 16 carbon atoms and an analogous series based upon cetyl alcohol, a linear C16, were studied as hydrophobes.
Pelargonic acid in enhanced oil recovery
Authors: Noureddini H. , Rempe M. L.
Published: November 2006

Oxidation of monounsaturated fatty acids, such as erucic and oleic acids, results in the formation of dibasic fatty acids, such as brassylic and azelaic acids. Dibasic acids find many industrial applications. Pelargonic acid is the co‐product of the process. Expanded use of dibasic acids would require an expansion in the existing and possibly new uses for pelargonic acid and its derivatives. In this study, the potential for using pelargonic acid in enhanced oil recovery is investigated. Experimental results are presented for the enhanced oil recovery by waterflooding with the aid of a surfactant.In situ formation of surfactant at the oil‐water interface vs. the formation of surfactant in the floodwater prior to injection is examined.
Adolescent problem behavior: The effect of peers and the moderating role of father absence and the mother‐child relationship
Authors: Mason Craig A. , Cauce Ana Mari , Gonzales Nancy , Hiraga Yumi
Published: November 2006

Examined the effect of peer problem behavior, the absence of a father or equivalent in the home, and the mother‐adolescent relationship as predictors of adolescent problem behavior in a sample of 112 African American adolescents. Statistical analyses compared a moderator model to a mediational model and a cumulative risk model. As predicted, the moderator model was superior to the alternative models. Specifically, whereas the mediational model predicted that the effect of father absence and the mother‐child relationship upon adolescent problem behavior would be mediated by peer problem behavior, neither effected peer problem behavior or adolescent problem behavior. Similarly, a cumulative risk index did not predict either child or parent reports of problem behavior and was not sensitive to specific contingencies that existed between the predictor variables. In contrast, an interactive, moderator model described the data quite well. This model suggested that father or equivalent absence magnifies the negative impact of peer problem behavior, while a positive mother‐adolescent relationship attenuates this risk. A strong mother‐adolescent relationship also served to protect adolescents in father‐absent homes from the risk of peer problem behavior.
Review of progress in sterol oxidations: 1987–1995
Authors: Smith Leland L.
Published: November 2006

Material dealing with the chemistry, biochemistry, and biological activities of oxysterols is reviewed for the period 1987–1995. Particular attention is paid to the presence of oxysterols in tissues and foods and to their physiological relevance.
Phospholipid composition of neonatal guinea pig liver and plasma: Effect of postnatal food restriction
Authors: Hunt Alan N. , Burdge Graham C. , Postle Anthony D.
Published: November 2006

Preterm guinea pigs were delivered on day 65 of gestation (term=68 d) and were allowed either free or restricted access to food for the subsequent 48 h. Plasma phosphatidylcholine (PC) concentration increased postnatally from 190 (range 144–307) to 751 (426–1039) and 883 (758–977) μM for fed and starved pups, respectively. Plasma PC composition in both groups of pups was characterized by selective and equivalent relative increases to individual molecular species containing 18∶0 at thesn‐1 position. Hepatic PC concentration increased from 6.75 (5.41–8.20) to 8.65 (6.54–10.63) and 9.23 (8.18–10.17) μmol/g for fed and starved pups, respectively, and, under all conditions, hepatic PC molecular composition closely mirrored that of plasma PC. These results support the hypothesis that the molecular species composition of plasma PC for the guinea pig in the immediate postnatal period is determined largely by the composition of the hepatic PC pool destined for lipoprotein secretion. Hepatic PC composition and concentration of the starved neonatal guinea pig were maintained independently of any dietary nutrient intake, at the expense of mobilization of extra hepatic lipid reserves. While this adaptive mechanism has inherent limited survival potential in neonatal starvation, it has implications for studies measuring plasma phospholipid fatty acid compositions as biochemical markers of dietary fat intake in preterm infants.
An improved method for rapid analysis of the fatty acids of glycerolipids
Authors: Ichihara Ken’ichi , Shibahara Akira , Yamamoto Kohei , Nakayama Takao
Published: November 2006

An improved rapid procedure to determine the fatty acid composition of glycerolipids is described. The procedure includes KOH‐catalyzed transesterification and high‐speed gas chromatography. Glycerolipids (20–40 mg) were mixed with 2 mL of hexane and 0.2 mL of 2 M methanolic KOH at room temperature for 1–2 min. The fatty acid methyl esters in the hexane layer were analyzed by gas chromatography on 10% SP‐2340 at 240°C. Methyl linolenate and docosahexaenoate eluted within 2 and 5 min, respectively. Analysis was thus completed with 5 min for common vegetable oils and 8 min for fish oils.
Functionalization at the double‐bond region of jojoba oil. 8. Chemical binding of jojoba liquid wax to a polymer matrixvia an amine “spacer”
Authors: Binman S. , Belfer S. , Shani A.
Published: November 2006

Jojoba wax was chemically bonded to a polymer matrixvia stable C‐N covalent bonds. The polymer matrix was prepared by amination of several types of styrene‐divinyl benzene or styrene‐vinylbenzylchloride‐divinylbenzene copolymers with diamines or polyethylene imines (polyamines). The jojoba wax was attached to the aminated polystyrene matrix by reacting an allyl‐brominated derivative of jojoba with the matrix to form a C‐N bond between the matrix and the jojoba wax. The amount of bound jojoba wax added to the polymer was in the range of 20–70% (w/w), depending on the type of polymer matrix and reaction conditions. The double‐bond regions in the jojoba wax bonded to the matrix were preserved, and they were subsequently functionalized by phosphonation and sulfur‐chlorination reactions.
Mineral acid‐catalyzed condensation of meadowfoam fatty acids into estolides
Authors: Isbell Terry A. , Kleiman Robert
Published: November 2006

Meadowfoam fatty acids (83% monoenoic fatty acid), reacted with 0.01–0.1 mole equivalents of perchloric acid, gave 33–71% yield of estolide, an oligomeric 2° ester, resulting from self condensation. Equimolar amounts of perchloric acid to fatty acid failed to produce estolide but converted the fatty acids to a mixture of lactones, mainly γ‐eicosanolactone. Temperature plays a critical role; higher temperatures (75–100°C), at the same acid concentration, provide lactones while lower temperatures (20–65°C) yield estolides. Lower acid levels (<0.1 mole equivalents) gave the best yields (≈70%) at 65°C. The estolide and monomer were characterized by nuclear magnetic resonance, infrared high‐pressure liquid chromatography, gas chromatography, gas chromatography/mass spectrometry. The estolide is a mixture of oligomers with an average distribution near 1.65 ester units. The ester linkages are located mainly at the original double bond positions but have some positional isomerization to adjacent sites in accord with carbocation migration along the alkyl chain. The residual double bond of the estolide was extensively isomerized fromcis totrans and positionally along the chain. The distilled monomer is similar in structure to the unsaturated portion of the estolide with geometrical and positional double bond isomerization. In addition, a significant amount of cyclization of the fatty acids to lactone (≈30%) had occurred.
Study of reaction and kinetics in pyrolysis of methyl ricinoleate
Authors: Guobin Han , Zuyu Liu , Suling Yao , Rufeng Yan
Published: November 2006

The effects of pyrolysis temperature, space‐velocity, and dilution ratio of starting materials on the reaction have been studied in the pyrolysis of methyl ricinoleate. The reaction parameters were optimized to obtain yield ranges of 25.8–26.7% for heptaldehyde and 45.7–46.5% for methyl undecenoate. The kinetic study showed that pyrolysis of methyl ricinoleate is a first‐order reaction at 828–878 K, and the activation energy is 1.729×105 j/mol.
The isolation of hydroxy acids from lesquerella oil lipolysate by a saponification/extraction technique
Authors: Hayes Douglas G. , Carlson Kenneth D. , Kleiman Robert
Published: November 2006

The lipolysate from immobilizedRhizomucor miehei lipase (Lipozymetm)‐catalyzed hydrolysis of lesquerella oil contains typically 35% free fatty acid (FFA), 2% monoglyceride, 25% diglyceride (DG), and 38% triglyceride (TG). Of the FFA, 75–80% are hydroxy acids (HFA). Various methods for isolating HFA from the lipolysate were examined, and a novel saponification/extraction method was developed. Lipolysate was mixed with 4 vol equivalents each of KOH/phosphate buffer and polar organic solvent. Hexane was then added to enhance phase separation. Three phases formed: a lower aqueous phase containing nothing of interest, a polar organic solvent middle phase that contained mostly fatty acid soaps, and a hexane‐rich upper phase that contained mostly DG and TG, which can be recycled to a relipolysis step. The middle phase, when treated with concentrated hydrochloric acid, NaCl‐saturated water, and hexane, released the FFA into the hexane. This fraction, referred to as the “Product” contained >99% of the FFA released in the lipolysis. “Product” consisted of 85–90% FFA, of which 75–80% was HFA. The other 10–15% of the “Product” consisted of partial glycerides and TG. The most critical parameters for the extraction are the pH of the aqueous solution and the polarity of the organic solvent (acetone was found to be the best choice). Additional purification steps for the “Product” are discussed.
Effect of dehulling methods and desolventizing temperatures on proximate composition and some functional properties of sesame (Sesamum indicum L.) seed flour
Authors: Inyang U. E. , Ekanem J. O.
Published: November 2006

Sesame seeds were dehulled mechanically and in 10% sodium chloride solution before oil extraction and drying to obtain the flour. The effect of these dehulling methods on the proximate composition, oil and water absorption, emulsification, and foaming properties of the flour was investigated. The effect of desolventizing temperatures (80, 90, and 100°C) on these properties was also investigated. Protein contents of seeds, dehulled mechanically (MDSF) and in 10% NaCl solution (SDSF), were 58.5 and 52.1%, respectively. Carbohydrate and ash contents of both flours also varied. The oil and water absorption capacities of the flours were 268 and 252% for MDSF and 370 and 410% for SDSF, respectively. The emulsion capacity of the MDSF sample was slightly lower (20.0 mL oil/g sample) but more stable than the SDSF sample, whose value was 20.4 mL oil/g sample. The foam capacity of MDSF was, however, higher (48.5%) but less stable than SDSF (33.7%). An increase in desolventizing temperatures of the meal led to increases in oil and water absorption capacities of the flours. Foam and emulsion capacities, on the other hand, decreased with increase in temperature. Desolventizing temperatures had no effect on the stability of the formed emulsion but had a decreasing effect on the stability of the foam.
Influence of solvent content on phase‐transition temperatures of oil sedimen and solution viscosity in acetone/canola oil systems
Authors: Liu Hua , Przybylski Roman , Michael Eskin N. A.
Published: November 2006

The effect of acetone on phase transition behavior of sediment in canola oil was studied by differential scanning calorimetry under dynamic heating/cooling regimes. The melting temperature of sediment decreased with an increase in the solvent content of canola oil, suggesting an increase in the solubility of sediment in the oil solution. The crystallization of sediment in oil solution was facilitated by acetone, as indicated by the increase in the sediment crystallization temperature. Acetone dramatically reduced the viscosity of canola oil, particularly in the first 30% addition. The reduction of viscosity was far less with further addition of acetone. These results suggested that the optimum range of acetone content needed for sediment precipitation in canola oil would be in the range of 30–40%. A linear relationship was found between the density of canola oil and temperature. The influence of solvent on the density of canola oil/acetone solution can be accounted for by the mixing theory of ideal solutions, whereas the effect of temperature on the dynamic viscosity of oil solution is best described by a modified Arrhenius equation.
Improved quantitative13C nuclear magnetic resonance criteria for determination of grades of virgin olive oils. The normal ranges for diglycerides in olive oil
Authors: Vlahov Giovanna
Published: November 2006

A quantitative method was established to determine the presence and composition of mono‐, di‐, and triglycerides of olive oils of superior gradevia13C NMR. The total diglyceride content and the ratio ofsn‐1,2‐ andsn‐1,3‐diglycerides in extra virgin oils extracted from different olive cultivars were correlated with maturity. The correlation can be applied to identify the oils by variety. No monoglycerides were detected in the oils examined.
Restructing butterfat through blending and chemical interesterification. 1. Melting behavior and triacylglycerol modifications
Authors: Rousseau Dérick , Forestière Karine , Hill Arthur R. , Marangoni Alejandro G.
Published: November 2006

Chemical interesterification of butterfat‐canola oil blends, ranging from 100% butterfat to 100% canola oil in 10% increments, decreased solid fat content (SFC) of all blends in a nonlinear fashion in the temperature range of 5 to 40°C except for butterfat and the 90∶10 butterfat/canola oil blend, whose SFC increased between 20 and 40°C. The sharp melting associated with butterfat at 15–20°C disappeared upon interesterification. Heats of fusion for butterfat to the 60∶40 butterfat/canola oil blend decreased from 75 to 60 J/g. Blends with >50% canola oil displayed a much sharper drop in enthalpy. Heats of fusion were 30–50% lower on average for interesterified blends than for their noninteresterified counterparts. Both noninteresterified and interesterified blends deviated substantially from ideal solubility, with greater deviation as the proportion of canola oil increased. The change in the entropy of melting was consistently higher for noninteresterified blends than for interesterified blends. Chemical interesterification generated statistically significant differences for all triacylglycerol carbon species (C) from C30 to C56′ except for C42′ and in SFC at most temperatures for all blends.
Restructuring butterfat through blending and chemical interesterification. 2. Microstructure and polymorphism
Authors: Rousseau Dérick , Hill Arthur R. , Marangoni Alejandro G.
Published: November 2006

Blending of butterfat with canola oil and subsequent chemical interesterification modified the crystal morphology and X‐ray diffraction patterns of butterfat, 90∶10 (w/w), and 80∶20 (w/w) blends of butterfat‐canola oil. The morphology of 50∶50 (w/w) was also greatly influenced by interesterification.

Polarized light microscopy revealed that addition of canola oil led to gradual aggregation of the crystal structure. Scanning electron microscopy revealed all samples to be mixtures of defined crystalline regions and amorphous areas with greater amorphism as oil content increased. Most samples revealed segregation of solid from liquid. Confocal laser scanning microscopy of butterfat revealed complex aggregated structures that were composed of outwardly radiating filaments from a central nucleus. X‐ray diffraction analysis revealed a predominance of β′ and a small proportion of β crystals for all samples examined except interesterified butterfat, which consisted solely of β′ crystals.
Chemical composition and physical properties of soft (tub) margarines sold in Malaysia
Authors: Idris Nor Aini , deMan Leny , Tang T. S. , Chong C. L.
Published: November 2006

Seven samples of domestic and imported Malaysian tub margarines were analyzed for their fatty acid and triglyceride (carbon number) composition, solid fat content, dropping and softening points, crystallization temperature, polymorphic form, color, and textural attributes. Domestic margarines were formulated from palm oil or palm olein and palm kernel oil with a liquid oil but no hydrogenated oils. Two imported products contained hydrogenated palm oil product, which resulted in a high level of β′ crystals, whereas the domestic nonhydrogenated products contained more β than β′ crystals. Crystal habit was related to the fatty acid and triglyceride composition of the high‐melting glycerides. Domestic products were firmer in texture, probably because they were formulated to be sold in a tropical climate.
Determination of the oxidative stability of vegetable oils by rancimat and conductivity and chemiluminescence measurements
Authors: Mathäus Bertrand W.
Published: November 2006

The oxidative stability of five different oils was determined by Rancimat analysis with conductivity and chemiluminescence measurements for evaluation of the induction periods. Samples of oil, taken at intervals from the Rancimat apparatus, were used for chemiluminescence measurements. The chemiluminescence results were plotted vs. time, and the resulting curves were evaluated with a graphical tangential procedure in the same way as the curves of the Rancimat method (conductivity measurement). Induction periods of the oils assessed by Rancimat and chemiluminescence methods showed a significant linear correlation (r=0.9865). The temperature dependence of the induction periods evaluated by chemiluminescence and by conductivity was investigated with walnut oil. A marked temperature dependence was observed for both.
The effect of temperature on lipid classes and their fatty acid profiles inLipomyces starkeyi
Authors: Suutari M. , Rintamäki A. , Laakso S.
Published: November 2006

The effect of environmental temperature on fatty acid contents of major lipid classes was determined inLipomyces starkeyi at 30, 20, and 10°C. When the temperature was reduced from 30 to 20°C, the linolenic acid content increased in phosphatidylcholine but fell with further reduction to 10°C. The relative contribution of phosphatidylcholine and phosphatidylethanolamine that contained the next lowest‐melting fatty acids, palmitoleic and linoleic acids, increased on lowering the temperature from 20 to 10°C and, concomitantly, the combined phosphatidylinositol and phosphatidylserine fraction decreased, and triacylglycerols were accumulated.