bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of influence of electrical induction on electrostatic interaction of atoms and molecules in solution. 1. Dependence of atomic charges in molecule from environment based on the model of FQ theory
Authors: Keshtova Svetlana V. , Keshtova Fatima M.
Published: November 2006

A new scheme to predict the behavior of atomic charges in molecules that depend on the environment is described. This method combines some advantages of earlier techniques (i.e., partial equalization of orbital electronegativities; fluctuating charge) and new approaches (i.e., two systems of σ and π electrons considered separately, with the use of new parameters). This method has avoided mistakes in the concept of dot charges on atoms. The new technique makes it possible to apply Thole's polarizabilities and van der Waals steric radii of atoms in molecules obtained from natural bond orbital (NBO) steric analysis. The new parameters demonstrate the degree of capability of the polarizabilities of atoms and bonds show the degree of mobility of electrons at creating the bond. The validity of our approximations is proved at a qualitative level. This new method can produce results showing good agreement with the results of ab initio calculations. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2007
Analysis of succinylacetone, as a Girard T derivative, in urine and dried bloodspots by flow injection electrospray ionization tandem mass spectrometry
Authors: Johnson David W. , Gerace Rosemarie , Ranieri Enzo , Trinh Minh‐Uyen , Fingerhut Ralph
Published: November 2006

Flow injection electrospray ionization tandem mass spectrometric methods for succinylacetone (SA) in 250 µL urine, using d5‐SA as internal standard, and in 3 mm dried bloodspots, using 13C4‐SA as internal standard, are described. Selectivity and sensitivity of analysis is achieved by the use of a mono‐Girard T derivative. Measured SA infant urine normal range (n = 20) is 0.013–0.27 µmol/mmol creatinine. Measured SA newborn bloodspot normal range (n = 152) is 0–0.30 µmol/L. Bloodspots from children with hepatorenal tyrosinemia type 1, and kept at room temperature for up to 7 years, afforded SA concentrations of 0.9–5.7 µmol/L. Copyright © 2006 John Wiley & Sons, Ltd.
A novel method for the study of the biophysical interface in soils using nano‐scale secondary ion mass spectrometry
Authors: Herrmann Anke M. , Clode Peta L. , Fletcher Ian R. , Nunan Naoise , Stockdale Elizabeth A. , O'Donnell Anthony G. , Murphy Daniel V.
Published: November 2006

The spatial location of microorganisms and their activity within the soil matrix have major impacts on biological processes such as nutrient cycling. However, characterizing the biophysical interface in soils is hampered by a lack of techniques at relevant scales. A novel method for studying the distribution of microorganisms that have incorporated isotopically labelled substrate (‘active’ microorganisms) in relation to the soil microbial habitat is provided by nano‐scale secondary ion mass spectrometry (NanoSIMS). Pseudomonas fluorescens are ubiquitous in soil and were therefore used as a model for ‘active’ microorganisms in soil. Batch cultures (NCTC 10038) were grown in a minimal salt medium containing 15N‐ammonium sulphate (15/14N ratio of 1.174), added to quartz‐based white sand or soil (coarse textured sand), embedded in Araldite 502 resin and sectioned for NanoSIMS analysis. The 15N‐enriched P. fluorescens could be identified within the soil structure, demonstrating that the NanoSIMS technique enables the study of spatial location of microbial activity in relation to the heterogeneous soil matrix. This technique is complementary to the existing techniques of digital imaging analysis of soil thin sections and scanning electron microscopy. Together with advanced computer‐aided tomography of soils and mathematical modelling of soil heterogeneity, NanoSIMS may be a powerful tool for studying physical and biological interactions, thereby furthering our understanding of the biophysical interface in soils. Copyright © 2006 John Wiley & Sons, Ltd.
Anxiety among university students during the SARS epidemic in Hong Kong
Authors: Wong Tze Wai , Gao Yang , Tam Wilson Wai San
Published: November 2006

A questionnaire survey was conducted during the Severe Acute Respiratory Syndrome (SARS) epidemic to assess the anxiety level and the perceived sources of stress among students from two universities where the outbreak occurred in the teaching hospital of one of the universities. The anxiety level caused by SARS in medical students at the teaching hospital was higher than in non‐medical students in the same university and lowest in students of the other university situated 20km away from the affected hospital. Copyright © 2006 John Wiley & Sons, Ltd.
Stress in New Zealand farmers
Authors: Firth H.M. , Williams S.M. , Herbison G.P. , McGee R.O.
Published: November 2006

This was a cross‐sectional study of stress in a stratified, random sample of New Zealand farmers (n = 1015). Data were obtained on farming‐specific environmental stressors, demographics and farm information. The stressor questionnaire grouped questions into seven sections; policy and procedures, finance, time pressures, hazards in farming, unpredictable factors in farming, geographical isolation, and community issues. The response rate was 60 per cent of farms. The most stressful events were ‘increased work load at peak times’, ‘dealing with workers’ compensation', ‘bad weather’, and ‘complying with health and safety legislation’. There were differences between men and women regarding stress experienced. Factor analysis found that the proposed model of farm‐specific stressors fitted the data moderately well. Age, being separated or divorced, being a deer farmer, the farm not making a profit in the last year, and supervising staff were independently associated with higher stress. The study highlights certain stressful factors that may be alleviated by action by farmer and government organizations as well as rural communities, including matters to do with staffing and health and safety, and financial and community support. Copyright © 2006 John Wiley & Sons, Ltd.
A qualitative study of self‐perceived effects of mindfulness‐based stress reduction (MBSR) in a psychosocial oncology setting
Authors: Mackenzie Michael J. , Carlson Linda E. , Munoz Marleny , Speca Michael
Published: November 2006

Quantitative research has shown Mindfulness‐based Stress Reduction (MBSR) programmes can reduce mood disturbance, improve quality of life, and decrease stress symptoms of cancer patients. However, the range of subjective effects experienced by programme participants has not been clearly described. Nine cancer patients who had participated in an 8‐week MBSR programme through the Tom Baker Cancer Centre's Department of Psychosocial Resources, and who continued to attend weekly drop‐in MBSR sessions were interviewed for this study. Qualitative research was conducted using grounded theory analysis. Data from semi‐structured interviews and a focus group were analysed using QSR N6 software to identify themes concerning the effects patients experienced by adding meditation to their lives. Five major themes emerged from the data: (1) opening to change; (2) self‐control; (3) shared experience; (4) personal growth; (5) spirituality. This information was used to develop specific theory concerning mechanisms whereby MBSR effects change for cancer patients. These understandings may be used to refine and further develop MBSR programmes to better assist patients during cancer diagnosis, treatment and recovery. Copyright © 2006 John Wiley & Sons, Ltd.
Polymorphic transformation of 1,3‐distearoyl‐sn‐2‐linoleoyl‐glycerol
Authors: Takeuchi M. , Ueno A. , Yano J. , Floter E. , Sato K.
Published: November 2006

Polymorphic transformation behavior of sub‐α1, sub‐α2, α, and γ in 1,3‐distearoyl‐sn‐2‐linoleoyl‐glycerol (SLS) has been studied with X‐ray diffraction, differential scanning caloremetry, and Fourier‐transform infrared spectroscopy. Synchrotron radiation X‐ray beam was employed to observe rapid transformation processes from the sub‐α and α forms to the γ form. The chain length structures were double in sub‐α1, sub‐α2, and α, whereas γ was of triple chain‐length structure. The subcell packing was pseudohexagonal for the two sub‐α forms, hexagonal for the α form, and parallel type for the γ form. In comparison with 1,3‐distearoyl‐sn‐2‐oleoyl‐glycerol (SOS), the occurrence behavior of sub‐α, α, and γ of SLS was the same as that of SOS. However, the absence of β′ and β was unique for SLS. The chain‐chain interactions between the linoleoyl moieties may stabilize the γ form, prohibiting the transformation into β′ and β forms. The presence of two cis double bonds may cause this stabilization, revealing the disordered chain conformation of the unsaturated chains.
Kinetics of palm oil transesterification in a batch reactor
Authors: Darnoko D. , Cheryan Munir
Published: November 2006

Methyl esters were produced by transesterification of palm oil with methanol in the presence of a catalyst (KOH). The rate of transesterification in a batch reactor increased with temperature up to 60°C. Higher temperatures did not reduce the time to reach maximal conversion. The conversion of triglycerides (TG), diglycerides (DG), and monoglycerides (MG) appeared to be second order up to 30 min of reaction time. Reaction rate constants for TG, DG, and MG hydrolysis reactions were 0.018–0.191 (wt%·min)−1, and were higher at higher temperatures and higher for the MG reaction than for TG hydrolysis. Activation energies were 14.7, 14.2, and 6.4 kcal/mol for the TG, DG, and MG hydrolysis reactions, respectively. The optimal catalyst concentration was 1% KOH.
A kinetic study of phospholipid extraction by degumming process in sunflower seed oil
Authors: Pan L. G. , Campana A. , Toms M. C. , n M. C. A.
Published: November 2006

During the refining process of vegetable oils (degumming), phospholipids are eliminated by thermal treatment with water (hydratable phospholipids, HP) and other degumming agents such as phosphoric acid, citric acid, or acid mixtures (nonhydratable phospholipids, NHP). Samples of pressed crude sunflower oils were degummed with water and acids, and the corresponding pellets (gums) and supernatant oils were obtained by centrifugation. During the water degumming process, a decrease of more than 98% in the phosphatidylcholine (PC) content was achieved in 5 min; phosphatidylethanolamine (PE) was the most difficult compound to be removed. Phosphatidylserine, phosphatidic acid, and phosphatidylinositol (PI) presented an intermediate behavior. The optimal contact time for quantitative extraction of the most important HP (PC, PI, and PE) in crude sunflower oils was 35 min. For acid treatments, a rapid elimination of the residual levels of PC was registered (5 min); the optimal contact times for the quantitative removal of the NHP were 35 min for phosphoric acid und acid mixture, and 25 min for citric acid. Taking into account that PE was the most difficult component to be removed, its level could be used as a monitor to evaluate the efficiency of the degumming process.
The development of nonchromium catalyst for fatty alcohol production
Authors: Hattori Yasuyuki , Yamamoto Katsutoshi , Kaita Jun , Matsuda Morio , Yamada Shuichi
Published: November 2006

Fatty alcohols are obtained by hydrogenation of fatty acid methyl esters derived from coconut oil and palm kernel oil. Cu−Cr has been widely used as a hydrogenation catalyst. We have developed a new environment‐friendly catalyst that could substitute for the conventional Cu−Cr catalyst, preventing the release of toxic hexavalent Cr. Here we report the development of Cr‐free, Cu−Fe−Al oxide catalyst. We found that iron has a strong promoting effect nearly equivalent to that of Cr and that the addition of Al significantly improved the reuse property (durability) through a study of trivalent metal addition to Cu. Powder X‐ray diffraction analysis of the used catalyst revealed that the Al addition suppressed the transformation of the CuFe2O4 component (Cu−Fe spinel) to α‐Fe. It was concluded that the stabilization of CuFe2O4 during reduction improved the catalyst durability. A plant‐scale experiment confirmed that the Cu−Fe−Al oxide catalyst performs as well as the conventional Cu−Cr catalyst.
Low‐temperature phase behavior of vegetable oil/co‐solvent blends as alternative diesel fuel
Authors: Dunn R. O. , Bagby M. O.
Published: November 2006

Vegetable oils (triacylglycerols) have many characteristics that make them attractive candidates as renewable alternative fuels for compression‐ignition (diesel) engines. Unfortunately, vegetable oils are too viscous to be compatible with modern direct‐injection diesel fuel systems and engines. Co‐solvent blending is a simple and flexible technology that reduces viscosity by mixing the oil with low molecular weight alcohol. A co‐solvent (A), consisting, of surfactant plus an amphiphilic compound, is added to solubilize otherwise nearly immiscible oil‐alcohol mixtures into a single‐layer (isotropic) solution. This work examines low‐temperature phase behavior of two soybean oil (SBO)/methanol mixtures solubilized by A=unsaturated long‐chain (C18) fatty alcohol/medium‐chain alkanol (n‐butanol and 2‐octanol), one SBO/methanol mixture solubilized by A=triethylammonium linoleate/2‐octanol, and one SBO/95 wt% ethanol (E95) mixture solubilized by n‐butanol. The E95‐blend was further blended in 1∶1 (vol/vol) mixtures with No. 2 diesel fuel. Two types of anisotropic phase behavior were observed; formation of a cloudy layer of solid crystals suspended in bulk solution (Type 1) and formation of two immiscible liquid layers (Type II). The type of phase separation in a given solution was influenced by phase separation temperature (Tϕ) relative to the crystallization characteristics of compounds in the SBO and fatty alcohol or amine constituents present in solution. Solutions with relatively low Tϕ values experienced crystallization of small solid particles favoring Type 1 separations. Conversely, solutions with Tϕ sufficient to avert crystallization of high melting point compounds favored Type II separations where Tϕ=critical solution temperature (Tcritical). Increasing the A/oil (SBO or No. 2 diesel/SBO mixture) mass ratio decreased Tϕ while increasing the mass fraction of alcohol (methanol or E95) increased Tϕ. This work shows that vegetable oil/A‐based blends can be formulated with cold flow properties superior with respect to cloud point and comparable with respect to kinematic viscosity (v) of methyl soyate (biodiesel), either neat or blended with petroleum middle distillates.
Characterization of triglycerides isolated from jojoba oil
Authors: Van Boven M. , Holser R. A. , Cokelaere M. , Decuypere E. , Govaerts C. , Lemey J.
Published: November 2006

Triglyceride compounds isolated from jojoba seed oil by column chromatography were composed predominantly of C18′ C20′ C22′ and C24 n−9 fatty acids with minor amounts of saturated C16. Chain length and double‐bond positions were determined by gas‐liquid chromatography and gas‐liquid chromatography‐mass spectrometry of the corresponding methyl ester and picolinyl ester derivatives. Triglyceride structures were analyzed directly by ion trap mass spectrometry. The analysis of minor compounds, can provide highly specific information about the identity of an oil.
Determining the blend level of mixtures of biodiesel with conventional diesel fuel by fiber‐optic near‐infrared spectroscopy and 1H nuclear magnetic resonance spectroscopy
Authors: Knothe Gerhard
Published: November 2006

Biodiesel, defined as the alkyl esters (usually methyl esters) of vegetable oils, is miscible with conventional diesel fuel at all blend levels. Until the present time, no rapid and reliable analytical method has existed for determining the blend level of biodiesel in conventional diesel fuel. In the present work, near‐infrared (NIR) and nuclear magnetic resonance (NMR) spectroscopies were used to determine the blend level of biodiesel in conventional diesel fuel. Several regions in the NIR region (around 6005 cm−1 and 4800–4600 cm−1) are suitable for this purpose. The method is rapid and easy to use, and does not require any hardware changes when using the same instrument for monitoring the biodiesel‐producing transesterification reaction and determining biodiesel fuel quality. In 1H NMR spectroscopy, the integration values of the peaks of the methyl ester moiety and the aliphatic hydrocarbon protons in biodiesel and conventional diesel fuel were used for determining blend levels. The results of NIR and NMR blend level determinations are in good agreement.
Encapsulation of sea buckthorn kernel oil in modified starches
Authors: Partanen Riitta , Yoshii Hidefumi , Kallio Heikki , Yang Baoru , Forssell Pirkko
Published: November 2006

Encapsulation of CO2‐extracted sea buckthorn kernel oil and the stability of the products were investigated. Maltodextrin and an emulsifying starch derivative were used for encapsulation by spray drying. Both shell materials significantly increased the storage stability of sea buckthorn kernel oil, even though in maltodextrin capsules 10% of the total oil was extractable from the surface of the capsule. The cornstarch sodiium octenyl succinate derivative capsules contained essentially no surface oil. After 9 wk storage at controlled conditions (20°C, RH 50%), PV of the unencapsulated oil was above 90 meq/kg, whereas in the encapsulated oils, the PV was still around 20 meq/kg. The PV of the encapsulated oil was dependent on the storage conditions. A small increase in temperature (from 20 to 25–30°C) and a significant increase in humidity (from RH 50 to RH 50–70%) decreased the stability of capsules. This was associated with the physical state of the microcapsule matrix and may be linked with glass transition of the wall polymers.
Influence of operating variables on yield and quality parameters of olive husk oil extracted with supercritical carbon dioxide
Authors: de Lucas A. , Rincón J. , Gracia I.
Published: November 2006

Supercritical fluid extraction is a viable alternative process for extracting oil from olive husk, a residue obtained in the olive oil production. We analyzed the effects of pressure (P) (100–300 bar), temperature (T) (40–60°C), solvent flow (1–1.5 L/min), and particle size (D) (0.30–0.55 mm) on extraction yield, and three oil‐quality parameters: acidity (OA), PV, and phosphorus content (PC). A response surface methodology based on the statistical analysis of the experimental data permitted us to obtain mathematical expressions relating the operational variables and parameters studied. At the best extraction condition of the experimental range analyzed (P=300 bar, T=60°C, D=0.30 mm, and solvent flow=1.25 L/min at standard conditions), the oil yield was 80% (w/w) with respect to hexane extraction, whereas the quality parameters OA, PV, and PC were 14% (w/w), 8 meq/kg, and 2.3·10−3% (w/w), respectively. These results were compared to those obtained by hexane Soxhlet extraction. The quality of the supercritical extract was superior, requiring only simple refining. This advantage may result in improved economics of the supercritical process in relation to the conventional extraction with hexane.
Oil fractionation as a preliminary step in the characterization of vegetable oils by high‐resolution 13C NMR spectroscopy
Authors: Zamora Rosario , Gómez Gemma , Dobarganes M. Carmen , Hidalgo Francisco J.
Published: November 2006

One hundred nine oil samples were separated chromatographically to obtain oil fractions with a decreased TAG content but with enhanced levels of the minor components that define oil genuineness and quality. The oils, which included virgin olive oils from different cultivars and regions of Europe and north Africa and refined olive, “lampante” olive, refined olive pomace, hazelnut, rapeseed, high‐oleic sunflower, corn, grapeseed, soybean, and sunflower oils, were fractionated on a silica gel column with hexane/diethyl ether as the mobile phase eluent. The method was highly reproducible, and the fraction obtained contained about 15% unmodified TAG and 85% polar compounds, which included polymeric TAG, oxidized TAG, DAG, MAG, and FFA, in addition to other minor polar components of the oils. The presence of these compounds, in an enriched fraction, should provide information about the thermal, oxidative, and hydrolytic alterations of the oils, as well as many compounds of interest in determining oil genuineness. The results indicate that these fractions can provide more information than the original oils for NMR or other spectroscopic studies used in the determination of oil quality.
Evolution of short‐chain glycerol‐bound compounds during thermoxidation of FAME and monoacid TAG
Authors: Berdeaux Olivier , Velasco Joaquín , Márquez‐Ruiz Glorida , Dobarganes Carmen
Published: November 2006

Methyl heptanoate and octanoate, methyl 8‐oxooctanoate and 9‐oxononanoate, and dimethyl suberate and azelate were quantitated in model systems of FAME, i.e., methyl oleate and linoleate, and monoacid TAG, i.e., triolein and trilinolein, heated at 180°C for 5, 10, and 15h. Polar compounds, ranging from 20.2 to 53.2% in TAG systems, were also quantitated as a reference for the level of degradation of the samples analyzed. Base‐catalyzed techniques were used for methylation as they did not modify the structure of the compounds of interest. The maximum amounts of short‐chain FAME and of aldehydic FAME obtained were of the same order (3–4 mg/g sample in methyl linoleate and trilinolein heated for 15 h). After a second methylation step with diazomethane, amounts of dimethyl suberate and azelate were also quantitated. The total amounts of dimethyl esters in TAG model systems ranged from 1.07 to 3.35 mg/g of heated sample and were similar to those found for total aldehydic FAME (from 1.03 to 3.15 mg/g of heated sample), suggesting that oxidation of the aldehydic acyl group to an acid acyl group was a major reaction.
Solid lubricant formulations containing starch‐soybean oil composites
Authors: Biresaw G. , Erhan S. M.
Published: November 2006

Starch‐oil composites comprising purified foodgrade corn starch (PFGS) and soybean oil (SBO) were investigated as potential ingredients for water‐based solid lubricant formulations. Current solid lubricants are almost exclusively petroleumbased and are used for protecting sheet metal and/or as sheet metal forming lubricants. Starch‐oil composites are preferred ingredients for formulating solid lubricants because they are based on renewable and abundantly available raw materials and also have superior environmental and health characteristics. Steel sheets coated with the PFGS‐SBO containing solid lubricant were evaluated for boundary coefficient of friction (COF) and wear properties using ball‐on‐flat test geometry. The COF was highly dependent on the SBO to PFGS ratio in the composite. In the absence of SBO, the COF was high (≈0.8) and decreased sharply with increasing SBO content to a minimum value of 0.07. Wear evaluation showed no scratches or lubricant transfer on the ball. There were also no wear tracks observed on the flat sheet before or after the solid lubricant was washed off. It was concluded that waterbased solid lubricants formulated with the PFGS‐SBO starch‐oil composite have acceptable friction and wear properties and should be evaluated further for use in sheet metal forming.
Fractionation and enrichment of CLA isomers by selective esterification with Candida rugosa lipase
Authors: Nagao Toshihiro , Shimada Yuji , Yamauchi‐Sato Yoshie , Yamamoto Takaya , Kasai Masaaki , Tsutsumi Kentaro , Sugihara Akio , Tominaga Yoshio
Published: November 2006

A commercial product of CLA contains almost equal amounts of cis‐9,trans‐11 (c9,t11)‐CLA and trans‐10,cis‐12 (t10,c12)‐CLA. We attempted to enrich the two isomers by a two‐step selective esterification using Candida rugosa lipase that acted on c9,t11‐CLA more strongly than on t10,c12‐CLA. An FFA mixture containing CLA isomers was esterified with an equimolar amount of lauryl alcohol in a mixture of 20% water and the lipase. When the esterification of total FA reached 50%, two isomers were fractionated in a good yield: t10,c12‐CLA was enriched in FFA, and c9,t11‐CLA was recovered in lauryl esters. The FFA were esterified again to enrich t10,c12‐CLA. At 27.3% esterification of total FA, the t10,c12‐CLA content in FFA increased to 64.8 wt% with 89.3% recovery: The ratio of the content of t10,c12‐CLA to that of two isomers was 95.9%. Lauryl esters obtained by the single esterification were employed for enrichment of c9,t11‐CLA. After the esters were hydrolyzed, the resulting FFA were esterified again with lauryl alcohol. At 62.0% esterification of total FA, the c9,t11‐CLA content in lauryl esters increased to 73.3 wt% with 79.4% recovery: The ratio of the content of c9,t11‐CLA to that of two isomers was 95.6%. In a 600‐g‐scale purification, molecular distillation was effective in separating the reaction mixture into lauryl alcohol, FFA, and lauryl ester fractions.
Influence of operation variables on quality parameters of olive husk oil extracted with CO2: Three‐step sequential extraction
Authors: de Lucas A. , Rincón J. , Gracia I.
Published: November 2006

Supercritical CO2 extraction is a viable alternative process for the extraction of high‐quality oil from olive husk (also known as olive pomace), a residue obtained in the production of olive oil. We analyzed the effect of pressure (100–300 bar), temperature (40–60°C), solvent flow (1–1.5 L/min), and particle size (0.30–0.55 mm) on four important quality parameters of the oil extracted with CO2: tocopherol concentration, extinction coefficients at 232 and 270 nm, and saponification value. Response surface methodology was used to obtain mathematical expressions related to the operating variables and parameters studied. Results from these experiments were also used to design a three‐step sequential CO2 extraction procedure to obtain a higher‐quality extract. The optimal operational sequence consisted of a first extraction step at 75 bar for 1 h using 1% (vol/vol) ethanol modifier, followed by a second extraction stage at 350 bar for 2.5 h without ethanol and a third step, also at 350 bar, for 2.5 h but using ethanol. These extraction conditions obtained an intermediate fraction of oil with 64% yield and all normal parameters according to European Commission food legislation. This fraction is suitable without any further refining. On the contrary, the oils obtained by hexane extraction and by conventional supercritical CO2 extraction at optimal conditions are suitable for human consumption after further refining. This last finding may result in improved economics of the sequential CO2 extraction process compared to the conventional extraction method with hexane.
Solubilization of lycopene in jojoba oil microemulsion
Authors: Garti Nissim , Shevachman Marina , Shani Arnon
Published: November 2006

The unique properties of jojoba oil make it an essential raw material in the manufacture of cosmetics. New, totally dilutable U‐type microemulsions of water, jojoba oil, alcohols, and the nonionic surfactant polyoxyethylene‐10EO‐oleyl alcohol (Brij 96V) have been formulated recently. Here, these microemulsions are shown to be capable of solubilizing lycopene, a nutraceutical insoluble in water and/or oil, much more effectively than the solvent (or a solvent and surfactant blend) can dissolve them. In water‐in‐oil (W/O) and oil‐in‐water (O/W) microemulsions with 10 and 90 wt% water, respectively, the normalized maximal solubilization efficiency α is ca. 20‐fold larger than its solubility. The solubilization capacity of the system is mainly surfactant‐concentration dependent. The lycopene resides at the interfaces of the W/O and O/W microemulsions and engenders significant structural changes in the organization of the microemulsion droplets. In the absence of lycopene, the droplets are spherical; when lycopene is added, compaction of the droplets and formation of threadlike droplets are observed. On further addition of lycopene, the bridging effect wanes and the droplets revert to a spherical shape. The enhanced solubilization demonstrated for lycopene opens up new options for formulators interested in making liquid and transparent products for cosmetic or pharmaceutical uses.
Diacylglycerols from butterfat: Production by glycerolysis and short‐path distillation and analysis of physical properties
Authors: Yang Tiankui , Zhang Hong , Mu Huiling , Sinclair Andrew J. , Xu Xuebing
Published: November 2006

The aim of this paper was to develop a process for the production of DAG from butterfat through glycerolysis and short‐path distillation and to evaluate the physical properties of the DAG in comparison with the original butterfat. Chemical glycerolysis produced a mixture of acylglycerols containing DAG together with MAG and TAG. From the mixture of glycerolysis products, MAG were removed through three consecutive distillations (vacuum <0.001 mbar) at 150°C. TAG were separated from DAG by distillation at 210°C, which gave a product with more than 80% DAG in the distillates. Distillation temperatures had significant effects on acyl migration. The formation of desirable 1,3‐DAG was favored at higher temperatures. Under 210°C distillation, the equilibrium ratio of 6∶4 was obtained between 1,3‐DAG and 1,2(2,3)‐DAG. The FA profile of the DAG product was relatively similar to the original butterfat. The total DAG recovery was around 77% in the pilot‐scale production. The different patterns of m.p. were observed between butterfat and the DAG fraction produced as well as the MAG fraction collected. Solid fat content profiles of the DAG fraction and its mixtures with rapeseed oil possessed trends similar to those of the corresponding butterfat and its mixtures with rapeseed oil. Compared with butterfat, the DAG fraction behaved differently in its thermal profiles, crystallization patterns, and rheological properties; for example, the dropping point was 13°C higher for the latter than for the former, and the crystal pattern was mostly β form for the latter, whereas the former was the β′ form.
Use of liquid carbon dioxide to remove hexane from soybean oil
Authors: Eller Fred J. , Taylor S. L. , Curren M. S. S.
Published: November 2006

Liquid carbon dioxide (L‐CO2) was investigated as a means to separate hexane from the mixture of soybean oil (SBO) and hexane resulting from the hexane extraction of soybeans. Using a fractionation tower, 5 vol of CO2 (i.e., 100, 200, 300, 500, and 1000 L expanded gas) were passed through 50 mL of two concentrations of n‐hexane (i.e., 10 and 25% w/w) in SBO. After passing through the hexane/SBO mixture, the expanded CO2 was passed through a chilled collection flask to capture extracted hexane and SBO. The raffinate SBO was removed from the column and analyzed for residual hexane using International Organization for Standardization Method 9832:2002. Residual hexane decreased as the amount of L‐CO2 used increased and was less than 20 ppm after 200 L of CO2. The amount of SBO extracted increased with the volume of CO2 used. Significantly more SBO and hexane were collected from the 25% sample than the 10% sample. During the extraction of the mixture, the CO2 selectively carried over TG with lower M.W. This research demonstrates the ability to use L‐CO2 to remove haxane from mixtures of hexane and SBO at both low pressures and temperatures.
High‐resolution NMR of irradiated almonds
Authors: Ribó Josep M. , Crusats Joaquim , El‐Hachemi Zoubir , Feliz Miguel , Sanchez‐Bel Paloma , Romojaro Félix
Published: November 2006

Electron beam‐irradiated peeled almonds (dose rate <5kGy) were subjected to a sensory test, ESR, and solid state 1H and 13C NMR spectroscopy using an improved magicangle probe. In the sensory test, changes were detected only for high radiation doses, and these were similar to those produced by aging. ESR detected significant differences between irradiated and nonirradiated samples, although these differences in free radical content tended to disappear with aging. Slightly higher DG content was detected in the irradiated sample by high‐resolution solid‐state NMR spectra.
Phytosterols, triterpene alcohols, and phospholipids in seed oil from white lupin
Authors: Hamama Anwar A. , Bhardwaj Harbans L.
Published: November 2006

This study was conducted to determine effects of genotypes and growing environment on phytosterols, triterpene alcohols, and phospholipids (PL) in lupin (Lupinus albus L.) oil from seven genotypes grown in Maine and Virginia. The unsaponifiable lipid (UNSAP) and phospholipid (PL) fractions ranged from 2.1 to 2.8% and from 2.6 to 2.8% of oil, respectively. UNSAP in lupin oil contained 19.9 to 28.7% sterols and 17.3 to 22.0% triterpene alcohols. Growing location significantly affected contents of total PL, PS, phosphatidylglycerol, β‐sitosterol, campesterol, and β‐amyrin. Genotypic effects were significant for stigmasterol. PC (32.6 to 46.3% of PL), PE (21.6 to 32% of PL), and PS (11.2 to 17.9% of PL) were the major PL in lupin oil. The concentration of PL classes in lupin oil were in the following descending order: PC>PE>PS>PI>phosphatidic acid > lysophosphatidylcholine > phosphatidylglycerol > diphosphatidylglycerol. In descending order of abundance, the sterols present in lupin oil were: β‐sitosterol > campesterol > stigmasterol > Δ5‐avenasterol > Δ7‐stigmastenol Lupeol was the most prominent triterpene alcohol in lupin seed oil. In general, growing environment had a much greater influence on lupin oil characteristics than the genotypes.
Edible acetylated monoglyceride films: Effect of film‐forming technique on moisture barrier properties
Authors: Guillard V. , Guilbert S. , Bonazzi C. , Gontard N.
Published: November 2006

The influence of film‐forming techniques on the moisture barrier efficiency of acetylated MG (AMG) films tested in real conditions at the interface between an agar gel (AG) and sponge cake (SC) was investigated. Three systems were studied: self‐supporting films, sprayed films, and cast films. The moisture distribution profiles of the AG/AMG/SC systems were determined experimentally and by using a predictive model for both self‐supporting films of various thicknesses and formed‐in‐place (sprayed or cast) films. Increasing the thickness of the self‐supporting films had no influence on moisture barrier efficiency, probably due to the high stability of the AMG material. Formed‐in‐place films were 40% less efficient than the self‐supporting films whatever the application procedure used (spraying or casting) because of their poor integrity due to the roughness of the SC surface.
Correlation between 1H NMR and traditional methods for determining lipid oxidation of ethyl docosahexaenoate
Authors: Falch Eva , Anthonsen Henrik W. , Axelson David E. , Aursand Marit
Published: November 2006

Lipid oxidation includes a complex set of chemical reactions; and no single analytical method is available to give a satisfactory description of lipid oxidation status. High‐resolution NMR spectroscopy techniques were tested to establish possible correlations with traditional analytical methods and to study lipid oxidation products. Ethyl esters of all‐cis 4,7,10,13,16,19‐docosahexaenoic acid (DHA) (22∶6n−3), with and without added α‐tocopherol, were oxidized in the dark at 25°C in an air‐circulating oven. Correlations were found between primary oxidation products (PV and conjugated dienes) and the appearance of peaks in the 8.0–10.5 ppm chemical shift region of the 1H NMR spectra. Multivariate data analysis (partial least squares; principal component regression) and the study of specific regions of the spectra obtained made it possible to easily separate samples of esters with and without α‐tocopherol based on the oxidation products formed. Based on knowledge about lipid oxidation products formed in marine lipids, selected oxidation products have been studied in the 1H NMR spectra with the aim of finding detection limits and their chemical shift values.
Formation and investigation of microemulsions based on jojoba oil and nonionic surfactants
Authors: Shevachman M. , Shani A. , Garti N.
Published: November 2006

The properties of jojoba oil make it uniquely suited as a raw material for the cosmetics industry. Water‐based, thermodynamically stable preparations of jojoba oil are essential in many formulations. New microemulsions were prepared based on jojoba oil and different nonionic surfactants, namely polyoxyethylene‐(ethylene oxide)10‐oleyl alcohol (Brij 96V) and ethoxylated sorbitan esters (Tweens). The effects of the surfactants and of primary alcohols as cosurfactants on the isotropic regions of the phase diagram were elucidated. It was found that, up to a certain cosurfactant chain length, the isotropic region expanded considerably as chain length increased. The size of the isotropic region also increased as a function of the ethylene glycol content of the aqueous phase in microemulsions based on ethoxylated alcohol but shrank when ethylene glycol was included in microemulsions prepared with ethoxylated sorbitan esters. Secondary structural phase transitions from water‐in‐oil to bicontinous and to oil‐in‐water structures (as determined by measuring conductivity and viscosity) were found to be related to jojoba oil content. Dynamic light scattering and small angle X‐ray scattering studies established that incorporation of jojoba oil into Brij 96V micelles caused micellar transformation from elongated to spherical droplets and a decrease in the aggregation number.
Functional properties of soybean and lupin protein concentrates produced by ultrafiltration‐diafiltration
Authors: Hojilla‐Evangelista Mila P. , Sessa David J. , Mohamed Abdellatif
Published: November 2006

Ultrafiltration followed by diafiltration (UF‐DF) was evaluated for the production of protein products from partially defatted soybean meal or undefatted lupin (Lupinus albus L.2043N) meal. This study determined the effects of UF‐DF on functional properties of the extracted proteins and compared the results with those of protein prepared by acid‐precipitation (AP). UF‐DF produced only protein concentrates (73% crude protein, dry basis, db), while AP produced protein isolates (about 90% crude protein, db). Soybean protein produced by UF‐DF showed markedly higher values for solubilities up to pH 7.0, surface hydrophobicity index, emulsion activity index, and foaming capacity than did the AP soybean protein. UF‐DF soy protein was also the most heat‐stable among all protein samples tested. With lupin proteins, only the surface hydrophobicity and emulsion activity indices were significantly improved by using UF‐DF. UF‐DF generally had no adverse effects on, and in most cases even improved, the functional properties of soy protein concentrate produced by this method. UF‐DF did not produce a comparable improvement in functional properties of lupin proteins as it did for soybean protein.
Use of the activation energy concept to estimate the quality reduction of packaged olive oil
Authors: Coutelieris Frank , Kanavouras Antonis
Published: November 2006

In the present study, the probability of packaged olive oil not reaching the end of its shelf life, Psafe, was used as a quality factor to evaluate the time taken for olive oils stored at various conditions to reach the end of their shelf lives. Psafe was used to comment on the activation energy required during the degradation process per actual or simulated case, and hexanal was used as the main quality‐related indicator. Based on the month after bottling at which Psafe reached 70%, the activation energy of an “equivalent” chemical reaction, representative of overall quality degradation, was calculated for several storage conditions. Using the differences between activation energies estimated using the above method, we found the most important factors influencing the shelf life of the packaged olive oil to be the initial storage period in the dark, the role of elevated temperatures, and the presence of light, either continuous or in alternating patterns, in association with the packaging materials used in this study. These results were in qualitative agreement with previously reported experimental observations and simulations, indicating the validity of using Psafe, and of activation energies calculated from it, to predict the shelf life of packaged olive oil.
Production of conjugated linoleic acid isomers by dehydration and isomerization of castor bean oil
Authors: Villeneuve Pierre , Lago Regina , Barouh Nathalie , Barea Bruno , Piombo Georges , Dupré Jean‐Yves , Le Guillou Anne , Pina Michel
Published: November 2006

The possibility of combining dehydration and isomerization of castor bean oil as a means to obtain CLA as TAG forms was studied. First, dehydration was carried out using various catalysts and reaction parameters. Best results were obtained using phosphoric acid (0.1% w/w) at 280°C for 5 h. Under such conditions, satisfactory proportions of CLA were obtained (54% of total FA) with a majority of 9‐cis, 11‐trans isomer (61% of total CLA). Other catalysts such as bisulfate‐bisulfite, sulfuric acid, tungstic and phosphotungstic acids, or resins and zeolites were also tested. With the exception of resins and zeolites, these catalysts also led to CLA production but in limited amounts in comparison with phosphoric acid. In a second step, an isomerization reaction was carried out to transform the residual nonconjugated linoleic acid also produced during dehydration into CLA. Using Wilkinson catalyst [RhCl(PPh3)3] in ethanol solvent, dehydrated castor bean oil was isomerized in high yields (>98%), allowing a complete disappearance of nonconjugated linoleic acids. The resulting dehydrated/isomerized oil contained more than 87% CLA with the 9‐cis, 11‐trans isomer being predominant (40% of CLA fraction). Finally, urea fractionation was also applied on dehydrated/isomerized castor bean oil FA to obtain FFA products containing about 93% CLA.
Adsorption of amphiphiles at an oil‐water vs. an oil‐metal interface
Authors: Biresaw Girma
Published: November 2006

Studies were conducted to investigate whether adsorption of amphiphiles from oil onto a degreased metal can be predicted from knowledge about adsorption of the amphiphiles at the oil‐water interface. The surface of a degreased metal comprises oxides, hydroxides, and adsorbed water vapor, which form from the reaction of the metal with air and moisture. If the behaviors of amphiphiles at water‐oil and metal‐oil interfaces are similar, this information can be useful in the development of cheaper and quicker methods of estimating amphiphile adsorption properties on degreased metals. The amphiphiles used were safflower oil (SA) and jojoba oil (JO), both of which are plant‐based oils, and methyl palmitate (MP). SA is a triester whereas JO and MP are monoesters. The interfacial tension of water‐hexadecane was measured as a function of amphiphile concentration in hexadecane and used to estimate an interfacial‐based free energy of adsorption, ΔGads. The resulting interfacial‐based ΔGads values for SA were identical to those reported from friction‐based adsorption isotherms. The corresponding values for the monoesters were within the range reported from friction‐based adsorption isotherms.
Prediction of the chemical equilibrium constant for peracetic acid formation by hydrogen peroxide
Authors: Janković Milovan , Sinadinović‐Fišer Snežana
Published: November 2006

An expression for temperature dependence of the chemical equilibrium constant for peracetic acid synthesis from acetic acid and hydrogen peroxide in an aqueous solution, derived on the basis of the van't Hoff and Kirchhoff equations, was proposed. The reverse trend of the chemical equilibrium constant vs. temperature was apparent when the predicted values of the constant were compared with experimental ones taken from the literature. However, using the proposed model to calculate the chemical equilibrium constant resulted in better prediction of the equilibrium composition for peracetic acid synthesis at 297.5 K than using experimental data from the literature.
Removal of dioxins and PCB from fish oil by activated carbon and its influence on the nutritional quality of the oil
Authors: Maes Jeroen , De Meulenaer Bruno , Van Heerswynghels Peter , De Greyt Wim , Eppe Gauthier , De Pauw Edwin , Huyghebaert Andre
Published: November 2006

Fish oils are well‐known sources of nutritionally valuable components such as the n‐3 FA EPA and DHA as well as the fat‐soluble vitamins A, D, and E. However, some fish oils can be contaminated with considerable amounts of dioxins and dioxin‐like PCB. The most important challenge during fish oil refining is to remove these contaminants without altering the levels fining is to remove these contaminants without altering the levels of nutritionally valuable compounds and the oxidative status and stability of the oil. Treatment with an apolar adsorbent, e.g., activated carbon (AC), seems to be the most efficient process today. Very little information about the adsorption of different dioxin and PCB congeners is available. Four grades of AC were evaluated for their efficiency in removing these compounds. In addition, the effects of the treatment on the nutritional and oxidative quality of the oil were evaluated. After treatment of contaminated cod liver oil [5.4 ppt toxic equivalents (TEQ) polychlorinated dibenzo‐p‐dioxins and dibenzofurans (PCDD/F), 18.1 ppt TEQ dioxin‐like PCB] with 0.5% AC, almost all PCDD/F and up to 80% of the dioxin‐like PCB could be removed. AC showed low affinity for mono‐ortho PCB (<30% removal), which could be explained by their noncoplanar structure. Removal efficiencies were dependent on the grade and percentage of AC used. The treatment of contaminated cod liver oil caused no important effects on oil quality or FA composition in the conditions tested.
A novel ∈‐lysine acylase from Streptomyces mobaraensis for synthesis of N∈‐acyl‐l‐lysines
Authors: Koreishi Mayuko , Kawasaki Ryoko , Imanaka Hiroyuki , Imamura Koreyoshi , Nakanishi Kazuhiro
Published: November 2006

A novel ∈‐lysine acylase (N6‐acyl‐l‐lysine amidohydrolase; EC 3.5.1.17) was isolated from Streptomyces mobaraensis and purified to homogeneity by SDS‐PAGE from the culture broth. The purified enzyme was monomeric, with a molecular mass of approximately 60 kDa. The enzyme was inactivated by the presence of 1,10‐phenanthroline and activated in the presence of Co2+ and Zn2+. The enzyme showed a pH optimum of 8.0 and was stable at temperatures of up to 50°C for 1 h at pH 8.0. The enzyme specifically catalyzed the hydrolysis of the amide bond of various N∈‐acyl‐l‐lysines. Furthermore, the enzyme efficiently catalyzed the synthesis of N∈‐acyl‐l‐lysines with fatty and aromatic acyl groups in an aqueous buffer. In the syntheses of N∈‐decanoyl‐l‐lysine, N∈‐lauroyl‐l‐lysine, and N∈‐myristoyl‐l‐lysine, the product precipitated and the yield was 90% or higher using 10 mM FA and 0.5 M l‐lysine as the substrate.
Fatty acid evolution during the storage of ground, roasted coffees
Authors: Vila María A. , Andueza Susana , Paz de Peña M. , Cid Concepción
Published: November 2006

During storage, the quality of coffee decreases, partially because coffee lipids degrade by lipolysis and oxidation. The aim of this study was to compare the evolution of the fatty acid (FA) profile in two ground, roasted coffees—Brazilian Arabica 100% (A100), and a blend of Brazilian Arabica 80% and Indian Cherry Robusta 20% (A80/R20)—throughout 180 d of storage. Linoleic acid (40.1% in A100, 40.2% in A80/R20) and palmitic acid (36.4% in both samples) were the main total FA. No significant change in the FA profile was observed throughout the storage period. A significantly higher total free fatty acid (FFA) initial concentration appeared in A80/R20 coffee (1108.5 mg/100 g fat) compared with A100 coffee (730.2 mg/100 g fat). Except for the first week of storage, similar FA oxidation patterns were found for both coffees, but FFA generation was faster in the A80/R20 blend than in A100.