bluuebunny/crossref_metadata_2025 huggingface dataset:
A comparison of commercial enzymes for the aqueous enzymatic extraction of corn oil from corn germ
Authors: Moreau Robert A. , Johnston David B. , Powell Michael J. , Hicks Kevin B.
Published: November 2006

An aqueous enzymatic method was developed to extract corn oil from corn germ. The basic steps in the method involved “churning” the corn germ with various enzymes and buffer for 4 h at 50°C, and an additional 16 h at 65°C, followed by centrifugation and removal of the oil layer from the surface. No hexane or other organic solvents are used in this process. By using oven‐dried corn germ samples (6 g) from a commercial corn wet mill, corn oil yields of about 80% were achieved using three different commercial cellulases. A fourfold scale‐up of the method (to 24 g of germ) resulted in oil yields of about 90%. Nine other commercial enzymes were evaluated and resulted in significant but lower oil yields. In the absence of enzymes, oil yields of 27 to 37% were achieved. The chemical compositions of hexane‐extracted vs. aqueous enzymatic‐extracted corn oils were very similar.
New hihg‐oleic peanut cultivars grown in the Southwestern United States
Authors: Jonnala Ramakanth S. , Dunford Nurhan T. , Dashiell Kenton E.
Published: November 2006

The chemical composition of five high‐oleic peanut lines grown in Oklahoma was examined. Tamrun OL 01, Tamrun OL 02, TX 977164, and TX 977239 were developed using conventional breeding procedures. SunOleic and Tamrun 96 were the parent lines. These lines demonstrated outstanding agronomic characteristics in Oklahoma. The peanut seeds analyzed in this study contained 42 to 49% oil, 25 to 29% protein, 9 to 12% total dietary fiber, about 2% ash, and 5% moisture. The peanut seeds were rich in potassium. Phosphorus and calcium were the two other two major minerals present in all the samples. The proximate compositions of all the breeding lines were within the range of the parent lines except they had 80% (w/w) oleic acid, which was significantly higher than the parent lines. This study indicates that conventional genetic selection for high‐oleic concentration does not cause substantial unintentional changes in peanut chemical compositions.
Experimental and predicted enthalpies of mixing of mixtures formed from alcohols and sunflower oil at 298.15 K
Authors: González Cristina , Piñeiro Manuel M. , Resa José M. , Legido Jose L. , Fanega M. Angeles
Published: November 2006

The enthalpies of mixing of systems formed from alcohols (methanol, ethanol, 1‐propanol, 2‐propanol, 1‐butanol, and 2‐butanol) and sunflower oil at 298.15 K are presented. Enthalpies were measured in the composition range in which the compounds were miscible. From the experimental measurements, we calculated the heat capacities of the mixtures. Several group contribution models were applied to estimate the enthalpies of mixing of these mixtures. The average deviations varied from 10 to 60%, depending on the model and compound. The best prediction in all cases was the Nitta model, with average deviations from 10 to 30%. The novelty of the work is that models of this type have not been applied previously to predict enthalpies of such large molecules, and the results of the estimates are of the same order as other types of compounds (pure compounds of small size).
Castor oil hydrogenation by a catalytic hydrogen transfer system using limonene as hydrogen donor
Authors: Martinelli Márcia , Schneider Rosana de Cassia de Souza , Baldissarelli Vanessa Zanon , von Holleben Maria Luiza , Caramao Elina Bastos
Published: November 2006

The hydrogenation of castor oil was investigated using a catalytic transfer hydrogenation system in which palladium on carbon was the catalyst and limonene was the solvent and hydrogen donor. The highest percentage of castor oil modification occurred at 178°C using 1% Pd/C and an oil/limonene ratio of 1∶3. The optimized system presented very good reproducibility and 100% conversion of the ricinoleate. GC using a mass spectrometer as detector and 1H NMR spectra of the products indicated that hydrogenation was accompanied by dehydrogenation leading to a mixture of 12‐hydroxy and 12‐keto stearic derivatives.
Modeling of kinetics for the enzymatic hydrolysis of sunflower oil in a high‐pressure reactor
Authors: Primožič Mateja , Habulin Maja , Knez Željko
Published: November 2006

This study presents a mathematical model for characterizing the Michaelis‐Menten type of sunflower oil hydrolysis, catalyzed by the lipase preparation Lipolase 100T (Novozymes Ays, Bagsvaerd, Denmark). Supercritical carbon dioxide was used as a solvent for this reaction. Computer modeling of the kinetics was done for the enzymatic hydrolysis of sunflower oil in a high‐pressure reactor using the MicroMath Scientist® program (Micro‐Math Research, St. Louis, MO). On the basis of the experimental results, we presumed the reaction was reversible. The suitability of the model was confirmed statistically with Student's t‐test. Good agreement was found between the experimental and calculated values for the concentrations of oleic and linoleic acids.
Acceleration of the thermoxidation of oil by heme iron
Authors: Artz William E. , Osidacz Patricia C. , Coscione Aline R.
Published: November 2006

Transition metals, including iron, occur naturally at significant concentrations in meat. Iron can be extracted from the food into the oil and potentially decrease the stability of the oil during frying by accelerating thermoxidation. The objective was to examine the thermoxidative stability of partially hydrogenated soybean oil after addition of heme iron. Heme iron (2.7 ppm) was added to the oil, and then oil samples were heated continuously at 160, 180, or 200°C for 72 h. Oil samples were removed for analysis every 12 h. The acid values, color, food oil sensor readings, and TAG polymer content of the heated oil samples were compared with oil samples containing no added iron that were held at the same temperatures. Generally, each oxidative index increased with (i) an increase in temperature, (ii) an increase in heating time, and/or (iii) the addition of iron. Generally, the extent of oxidation was greater for samples heated at 200°C than for oil samples heated at 160 or 180°C. The oil samples heated at 200°C reached the target polymer content of 20% after 27 h of heating. If heme iron accumulates in the oil, it will increase the rate of oxidation and thermal degradation and reduce the frying life of the oil.
Cottonseed extraction with mixtures of acetone and hexane
Authors: Kuk M. S. , Tetlow R. , Dowd M. K.
Published: November 2006

Cottonseed flakes were extracted with mixtures ofn‐hexane and acetone, with the concentration of acetone varying between 10 and 75%. Adding small amounts of acetone (≤25%) ton‐hexane significantly increased the extraction of free and total gossypol from cottonseed flakes. Sensory testing detected no difference in the odor of cottonseed meals produced either by extraction with 100%n‐hexane or by extraction with a 10∶90 (vol/vol) mixture of acetone/hexane. More than 80% of the free gossypol was removed by the 10∶90 mixture of acetone/hexane, whereas puren‐hexane extracted about 47% of the free gossypol from cottonseed flakes. A solvent mixture containing 25% acetone removed nearly 90% of the free gossypol that was removable by extraction with pure acetone; the residual meal had only a minimal increase in odor. In contrast, cottonseed meals produced by extraction with pure acetone had a much higher odor intensity. The composition of the cottonseed crude oil was insignificantly affected by the acetone concentration of the extraction solvent. The results indicate that mixtures of acetone andn‐hexane can be used as extraction solvents to produce cottonseed crude oil without the concomitant development of odorous meals.
Kinetic modeling of the glycerolysis reaction for soybean oils in supercritical carbon dioxide media
Authors: Moquin Paul H. L. , Temelli Feral , King Jerry W. , Palcic Monica M.
Published: November 2006

Production of MAG by glycerolysis is important for food, pharmaceutical, and cosmetic industries. Conducting glycerolysis in supercritical carbon dioxide (SC‐CO2) media has advantages over conventional alkali‐catalyzed glycerolysis. However, kinetic data are lacking for such conversions in the presence of SC‐CO2. The objectives of this study were to estimate the rate constants and elucidate the mechanism for the glycerolysis of soybean oil in SC‐CO2 using previously reported data. The data were taken from experiments using soybean oil, glycerol (glycerol/oil molar ratios of 15–25) and water (3–8% w/w) in SC‐CO2 at 20.7–62.1 MPa and 250°C for a 4 h period. Rate constants for the parallel glycerolysis and hydrolysis reactions were estimated for each processing parameter (glycerol/oil, water content, pressure) by minimizing the summed squared error between the values calculated from the experimental data and those obtained from the kinetic model. The results suggested that water and pressure had an effect on rate constants but the glycerol/oil ratio did not. Findings provide the kinetic modeling data necessary for the optimization of supercritical processes involving glycerolysis reactions for the production of MAG from vegetable oils.
Sophorolipid biosynthesis from a biodiesel co‐product stream
Authors: Ashby Richard D. , Nuñez Alberto , Solaiman Daniel K. Y. , Foglia Thomas A.
Published: November 2006

We applied a biodiesel co‐product stream (BCS) as a fermentation feedstock for the microbial synthesis of sophorolipids (SL). The BCS was composed of 40% glycerol, 34% hexane‐solubles (made up of 92% FA soaps/FAME and 6% MAG/DAG), and 26% water. Batch culture fermentations of the yeast Candida bombicola on pure glycerol resulted in low‐level synthesis of SL (∼ g/L). HPLC associated with atmospheric pressure CI‐MS (LC/APCI‐MS) revealed that the SL derived from pure glycerol had 99% of the FA side chains linked to the 4″ hydroxyl group of the sophorose sugar, resulting in a lactonic structure. In contrast, the use of the BCS as feedstock increased the SL yield to 60 g/L and the open‐chain form to 75% including both oleic acid and linoleic acid (along with their methyl esters) as the dominant species comprising the side chains. By favoring the open‐chain structure, the SL molecules (particularly the FA side chain) can be chemically modified without the need to open a lactone ring first. The ability to use the BCS as a feedstock for SL synthesis will provide an outlet for this residual material, thus helping to stimulate growth in the biodiesel market and the use of agricultural fats and oils from which the biodiesel was synthesized.
Response surface methodology applied to optimization of distilled monoglycerides production
Authors: Fregolente Leonardo Vasconcelos , Batistella César Benedito , Filho Rubens Maciel , Maciel Maria Regina Wolf
Published: November 2006

This work demonstrates that response surface methodology (RSM) is a powerful tool for the optimization of the production of distilled MG. Experiments with a centrifugal molecular distillator having an evaporation area of 0.0046 m2 were carried out using RMS to identify operating conditions that can lead to higher MG purity. The independent variables studied were the evaporator temperature (TEV) and the volumetric feed flow rate (Q). The experimental range was from 100 to 300°C for TEV and between 5 and 15 mL/min for Q. High‐performance size exclusion chromatography was used to evaluate TG, DG, MG, FFA, and glycerol (GL) compositions. Results were presented as MG concentration surfaces. Starting from a material with 10.8% of TG, 37.7% of DG, 43.6% of MG, and 7.2% of GL, the maximum MG, purity in the distillate stream with just one distillation step was 82.6% at a TEV equal to 250°C and Q equal to 5 mL/min. At these conditions, the MG recovery was 61%. A strategy was developed to obtain distilled MG with 96.3% purity.
Triglyceride selectivity of immobilized Thermomyces lanuginosa lipase in interesterification
Authors: Rønne Torben H. , Pedersen Lars S. , Xu Xuebing
Published: November 2006

The triglyceride (fatty acid) selectivity of an immobilized lipase from Thermomyces lanuginosa (Lipozyme TL IM) was investigated in lipase‐catalyzed interesterification reactions between two nono‐acid TG in n‐hexane. Tristearin (tri‐C18∶0) was used as a reference in a series of TG with saturated FA from tri‐C4∶0 to tri‐C20∶0, except for tri‐C6∶0, and in a series of unsaturated FA from tri‐C18∶1 to tri‐C18∶3. The quantification was performed by HPLC, and different methods of selectivity evaluation were used. None of the methods used showed any significant differences between the performances of the lipase on the different TG, indicating that Lipozyme TL IM is nonselective toward FA or TG in the system used. A response surface design was used to investigate the influence of water activities (aw) and reaction temperatures on the reactivity of Lipozyme TL IM with a system of tripalmitin (tri‐C16∶0) and trilaurin (tri‐C12∶0) in n‐hexane. An increase in temperature (40 to 60°C) was found to affect the reactivity of the lipase significantly. The reactivity of Lipozyme TL IM was unaffected by the change in aw from 0.1130 to 0.5289. An increase in aw only led to an increase in FFA formation.
Oxidative stability of healthful frying oil medium and uptake of inherent nutraceuticals during deep frying
Authors: Nasirullah  , Rangaswamy Baby Latha
Published: November 2006

Four healthful frying oil mediums have been formulated using sunflower (FOB‐I), groundnut (FOB‐II), mustard (FOB‐III), and palm olein (FOB‐IV) oils as base oils, and fortified with rice bran and crude sesame oils separately in the ratio of 60∶20∶20 (by vol). Oxidative stabilities have been ascertained by deep‐frying potato bajji (potato slices sandwiched with Bengal gram flour) continuously for 60 min for three cycles with a gap of 7 d each. The product had moisture between 12.8 and 16.0% and absorbed fat between 32.5 and 38.1%, making the oil media vulnerable to oxidation. The p‐anisidine values for leftover FOB‐I and FOB‐IV ranged from 10.8 to 24.4 and from 1.5 to 10.7, respectively, indicating that the former was a less and the latter a more stable combination. Hydroperoxide and conjugated dienes were assessed by UV spectrometry at λmax 230 nm. The O.D. was maximal (1.4) for FOB‐I samples for both leftover and absorbed oils for third‐cycle experiments. That there was no absorbance for the FOB‐III and‐IV samples indicated their absence. Estimation of oryzanol and sesamol in oil left over after deep frying and in the oil absorbed by the products indicated that distribution was equal and there was no loss of these active factors during deep frying. The study indicated that sunflower oil blend was the least stable and the palm olein blend was most stable.
Effects of herbs on hydrolytic and oxidative degradation of olive oil in canned tomatoes
Authors: Baiano Antonietta , Gomes Tommaso , Severini Carla
Published: November 2006

The effects of adding mixtures of herbs such as garlic, laurel, and marjoram on selected chemical indices of olive oil from canned dried tomatoes were studied for various storage periods of up to 1 yr. Conventional analytical indices measured included acidity, PV, and p‐anisidine value. Flavored samples showed kinetic constant values that were significantly (P=0.001) higher than unflavored ones, whereas oligopolymer and oxidized TG and DG contents were similar to or slightly higher than in the unflavored samples compared with those with herbs. The addition of the mixture of herbs slowed polymerization reactions but did not inhibit TG oxidation. Discrepancies between the results obtained by conventional analyses and high‐performance size‐exclusion chromatography indicated that the former approaches were insufficient to determine oxidative degradation of oil as a result of interferences from compounds in the food matrix.
Sensory and oxidative quality of screw‐pressed flaxseed oil
Authors: Wiesenborn D. , Kangas N. , Tostenson K. , Hall C. , Chang K.
Published: November 2006

Cold‐pressed flaxseed oil is an excellent source of dietary α‐linolenic acid (ALA). However, breakdown of ALA in the oil, either in the seed before or during storage, or as a result of processing, may result in unacceptable flavors. Screw‐pressed flaxseed oil from four seed lots and a commercial sample were analyzed for headspace volatiles (HV) by solid‐phase microextraction; for nutty, painty, and bitter flavors; and for overall quality. HV and sensory analyses were performed after storage for 7 d at room temperature and again after 15 wk at 4°C. Marked, significant differences were observed between samples for painty and bitter flavors and overall quality, but only slight differences for nutty flavor (P<0.05). Samples remained stable between the two storage periods. HV traces showed distinct differences between samples in number of peaks and in peak heights. Areas under peaks corresponding to select retention times were positively correlated (P<0.01) with nutty, painty, and bitter flavors. Therefore, the HV analysis by solid‐phase microextraction may be a useful tool for screening flaxseed lots to be used for the production of screw‐pressed oil.
Determination of conjugated linolenic acid content of selected oil seeds grown in Turkey
Authors: Özgül‐Yücel Sevil
Published: November 2006

Seeds originating from some Turkish sources were analyzed with respect to their characteristics and FA compositions. These seeds represented pomegranate (Punica granatum L.), bitter grourd (Momordica charantia L.), pot marigold (Calendula officinalis L.), catalpa (Catalpa bignonoides), bourdaine (Rhamnus frangula L.), Oregon grape (Mahonia aquifolium), sarsaparilla (Smilax aspera), mahaleb (Prunus mahaleb L.), black‐thorn (Prunus spinosa L.), cherry laurel (Prunus laurocerasus L.), and firethorn (Pyracantha coccinea). Bitter gourd and bourdaine seeds contain more than 20% oil. Catalpa, bourdaine, Oregon grape, blackthorn, and cherry laurel seed oil contents ranged from 15 to 20%. In the seeds from plants belonging to the Rosacea family, oil content ranged from 4.5 to 18.5%. Among the seed oils analyzed, pot marigold had one of the lowest oil contents (5.9%). Pomegranate contained the highest amount of total conjugated linolenic acid (CLNA) (86.0%). Seed oils of bitter grourd, pot marigold, mahaleb, and catalpa were rich in CLNA: 60.0, 29.5, 27.6, and 27.5%, respectively. Bourdaine, Oregon grape, and sarsaparilla seeds contained low amounts of CLNA. On the other hand, mahaleb, bourdaine, catalpa, Oregon grape, sarsaparilla, cherry laurel, blackthorn, and firethorn seed oils are basically oleic and linoleic acid‐rich oils and therefore have little drying ability (semidrying oil). The results show a potential for the use of endogenous Turkish seeds as a source of CLNA.
Hydrochlorination of oleic acid: Kinetics and Henry's constant
Authors: Doulia Danae , Klimentzos Dimitris
Published: November 2006

The addition reaction of gaseous hydrogen chloride to oleic acid (hydrochlorination) was investigated. Oleic acid was placed in an autoclave chamber, into which gaseous hydrogen chloride was fed, and the reaction was carried out under batch and semiflow conditions. The hydrochlorination of oleic acid by hydrogen cloride is a gas‐liquid reaction involving the initial absorption of hydrogen chloride into a quiescent liquid, accompanied by a reaction of the dissolved gas with the liquid to form chlorostearic acid. The course of the reaction was monitored by withdrawing oil samples at 30‐min intervals and determining the iodine value, acid value, and chlorine content. The kinetics of hydrochlorination was studied at constant pressure (40 atm). The experimental data were fitted to an irreversible pseudo zero‐order rate equation with the reaction constant k=2.293×10−7 mol/cm3·s. The solubility of HCl (Henry's constant) in chlorostearic acid was estimated from two types of batch experiments, including a single and double feed of HCl. The mean Henry's constant value for physical absorption was 3218 atm cm3/mol in the pressure range of 11.2–16 atm and at a temperature of 21°C. Similar batch experiments were performed in oleic acid, and the results supported the Henry's constant value determined for chlorostearic acid.
Monitoring of hydrogenation with various catalyst ratios
Authors: Cizmeci Melih , Musavi Anar , Kayahan Muammer , Tekin Aziz
Published: November 2006

Soybean oil was hydrogenated using two different nickel‐based commercial catalysts (Nysosel 222 and SP‐10) at various ratios in 4‐L reactors under constant conditions (165°C, 2 bar hydrogen pressure, and 500 rpm stirring rate). Trans isomer formation, reaction rates, selectivity (S) ratios, and melting behaviors of the samples were monitored during the reactions. When Nysosel 222 was used at 0.02, 0.03, and 0.04%, iodine values (IV) were reduced from 130.1 to 70.6, 50.9, and 44.7 and total trans isomers increased from 0 to 34.2, 43.3, and 40.5%, respectively, after 100 min of hydrogenation. However, SP‐10 reduced IV from 130.1 to 77.2, 75.7, and 71.3 after 100 min when used at 0.1, 0.15, and 0.2%, respectively, whereas total trans isomers were 58.6, 70.4, and 70.7%. Reaction rates increased with catalyst ratio and time but were higher for Nysosel 222 than for SP‐10 although 5–10 times less Nyosel 22 was used than SP‐10. Linoleate selectivity (S32) was almost constant for Nysosel 222, whereas it was higher but fell with time for SP‐10. Increasing the catalyst ratio decreased the time needed to reach the highest oleate selectivity (S21) ratios, and the IV values where the highest S21 were attained were different for the catalysts. Increases in m.p. of SP‐10 samples were slower after IV values of 80 were attained, where S21 ratios reached to higher values. Solid fat contents (SFC) of these samples fell markedly above 21.1°C, and steeped SFC curves were obtained.
Evaluation of SafTestTM methods for monitoring frying oil quality
Authors: Yee Foo Swee , Cuppett Susan , Schlegel Vicki
Published: November 2006

The feasibility of applying methods developed by Safety Associates, Inc., to monitor oil degradation products, including malondialdehydes (AldeSafeTM), FFA (FASafeTM), and peroxides (PeroxySafeTM), in fresh and heat‐abused deep‐fat frying oil was evaluated. Based on performance qualification studies, the AldeSafe method was the most suitable SafTestTM assay for monitoring the quality of frying oil because of its high accuracy, precision, linearity, and reproducibility, and low detection/quantitation limits. A strong correlation (r=0.924) between the AldeSafe method and its counterpart, AOCS Official Method Cd 19‐90, also supported the suitability of the SafTest method for monitoring oil quality. Moreover, the FASafe method had a moderately strong relationship with AOCS Official Method Ca 5a‐40 (r=0.761). Our studies suggest that this test can be applied for monitoring frying oil; however, certain method performance limitations must be considered for routine analysis purposes. In contrast, the PeroxySafe method probably should not be used to monitor heat‐abused oil without further development because of high variability, low accuracy, and low correlation (r=0.062) with the AOCS Official Method Cd 8‐53 assay.
Enzymatic transesterification of sunflower oil in an aqueous‐oil biphasic system
Authors: Oliveira A. C. , Rosa M. F.
Published: November 2006

A biphasic oil‐aqueous system for FAME production by enzymatic catalysis was studied. The transesterification of sunflower oil with methanol was catalyzed by free or immobilized lipases from Rhizomucor miehei (Palatase 20 000 L) and Humicola insolens (Lipozyme TL 100 L). The effects of protein amount, temperature, pH, and molar ratio of methanol to sunflower oil on the enzymatic reaction using free lipase were evaluated; the best results were obtained with H. insolens, at pH 5, 40°C, and 36.8 mg of protein. By using this lipase immobilized in Hypol® 2002 (64. 8 mg of protein) at a 6∶1 methanol/oil molar ratio and a 2∶1 volumetric oil/water phase ratio, an ester content of 96.1% and a conversion of 91.2% were achieved. The immobilized lipase could be reused, although a 30% reduction in conversion efficiency was observed after four uses.
Functionality of soy protein produced by enzyme‐assisted extraction
Authors: Jung S. , Lamsal B. P. , Stepien V. , Johnson L. A. , Murphy P. A.
Published: November 2006

This study investigated the potential of enzymes to increase soy protein extractability without causing protein degradation. The aqueous extraction of protein was performed from defatted soy flakes on a laboratory‐and pilot‐plant scale. Yields of protein and reducing sugars were determined in the alkali extracts obtained with cellulases and pectinase, added alone or as cocktails. Using 5% (wt/g of protein) Multifect pectinase resulted in the best improvement of protein yields, which were 50 and 17% greater than the controls in laboratory‐ and pilot‐plant‐scale trials, respectively. This enhanced protein extraction was accompanied by an increased reducing sugar content in the aqueous extract compared with the control. Under the conditions tested, no enzyme cocktail markedly increased the protein yield compared with the use of single enzymes. The solubility curve for Multifect pectinase‐treated soy protein isolate (SPI) was typical of SPI at pH 2–10. Its foam stability significantly improved, but the emulsification properties declined. Multifect pectinase markedly reduced the viscosity of SPI. SDS‐PAGE showed that the α’ and α subunits of β‐conglycinin were modified, and glycoprotein staining showed that these modifications were probably due to a protease secondary activity in the pectinase preparation. One cellulase and one pectinase were identified as effective in modifying the protein and reducing sugar extractablity from the defatted soy flakes.
Soy protein combined with copper and boron compounds for providing effective wood preservation
Authors: Yang In , Kuo Monlin , Myers Deland J.
Published: November 2006

Chromated copper arsenate (CCA), an arsenicbased wood preservative, is toxic to human health and the environment. Although CCA is stable in seasoned wood, there are potential dangers during CCA manufacture, lumber treatment, and waste disposal. This research was conducted to study the effectiveness of soy products to replace toxic chromium and arsenic compounds in wood preservative formulations. Three soy product (Arpro 2100, HM 90, and Supro 760) were used as fixative agents in preservative solutions containing anhydrous CuSO4 and Na2B4O7·10H2O. The decay resistance of treated wood blocks was measured by a soil‐block culture method. Despite the large molecular sizes of copper‐protein and copper‐boron‐protein complexes, southern pine sapwood was treatable with these preservative formulations. Wood samples treated with >6 kg°m−3 CuSO4 and 7.5 kg·m−3 soy product, and subsequently leached for 3 d and exposed to the decay fungus Gloeophyllum trabeum (Fr.) Mur., sustained only 0.5% weight loss over 12 wk. Wood samples needed 40 kg·m−3 CuSO4 and 50 kg·m−3 soy protein to resist the copper‐tolerant decay fungus Postia placenta (Fr.) M. Lars. & Lomb. These results suggest that soy‐based wood preservatives can prevent wood products from fungal attack and can replace CCA.
Analysis and characterization of edible oils by chemometric methods
Authors: Giacomelli Liliana M. , Mattea Miguel , Ceballos Claudio D.
Published: November 2006

Chemometric techniques have been used to group samples with similar features as well as to discriminate among experimental data on edible oils. The objective of this study was to provide a simple method for differentiating vegetable oil types and to classify unknown samples using analytical techniques commonly used in the edible oil industry. We used principal component analysis to study the relationship between FA composition, tocopherol levels, CIF (Commission Internationale de l'Eclairage) parameters, and a photometric color index. The total variance in the original data matrix was established mainly by three principal components. Data processing allowed the oil samples to be identified and created a 2‐D map as a fingerprint of the oil types. This analysis can be used successfully to differentiate vegetable oil types and classify them as crude or refined oils.
Computer simulation of fractal dimensions of fat crystal networks
Authors: Tang Dongming , Marangoni Alejandro G.
Published: November 2006

The rheological properties of fat‐structured products are determined by the microstructure of their fat crystal networks, which can be quantified by using microscopical and rheological techniques. Of particular interest to this study is the quantification of the fractal dimension of the network using these two techniques. Fractal dimensions determined by polarized light microscopy include box‐counting, particle‐counting, and Fouriertransform fractal dimensions, whereas the fractal dimensions determined by small deformation dynamic rheology exploit the dependence of the storage modulus on the solids' volume fraction. This work reveals that different microscopy fractal dimensions are sensitive to different microstructural factors within the fat crystal network, and thus have different physical meanings. The boxcounting fractal dimension, Db, increases with increases in crystal size and area fraction of the fat crystals, whereas the particlecounting fractal dimension, Df, is sensitive to the radial distribution pattern of fat crystals; and the Fourier‐transform fractal dimension, DFT, decreases with increasing crystal size. In the studies on the macroscopic physical properties of fat crystal networks, it is necessary to find the determining structural characteristics and then use the fractal dimensions that are most closely related.
Comparison of the frying stability of regular and high‐oleic acid sunflower oils
Authors: Normand L. , Eskin N. A. M. , Przybylski R.
Published: November 2006

The frying stability of a regular sunflower oil (RSFO) was compared with that of a high‐oleic acid sunflower oil (HOSFO). The rate of FFA formation was greater for HOSFO than RSFO during 72 h of frying. The content of tocopherols was much higher in RSFO and their degradation was markedly slower than that observed for HOSFO. The formation of total polar compounds, however, was similar for both oils despite the dramatic differences in FA composition. This study further confirms the limitations in predicting frying stability based solely on the FA composition and is consistent with earlier studies conducted in our laboratory.
Mechanism of the inhibition of calmodulin‐dependent neuronal nitric oxide synthase by flaxseed protein hydrolysates
Authors: Omoni Adetayo O. , Aluko Rotimi E.
Published: November 2006

This work was aimed at producing potential nutraceutical peptides from flaxseed protein hydrolysate that can bind to calmodulin (CaM) and inhibit the activity of CaM‐dependent neuronal nitric oxide synthase (nNOS), an enzyme that has been implicated in some forms of human diseases. Flaxseed protein isolate was hydrolyzed with alcalase, and the resultant protein hydrolysate was passed through a 1000‐Da M.W. cut‐off membrane to isolate low‐M.W. peptides. The permeate from the membrane was loaded onto a cation‐exchange column, and adsorbed peptides were separated into fractions I and II that had a content of 42 and 51% basic amino acids, respectively. Kinetic analyses showed that both fractions were capable of binding to CaM, which led to reductions in the activity of nNOS; the inhibition constant (Kj) was 5.97 and 2.55 mg/mL for fractions I and II, respectively. Double reciprocal plots showed that the mode of enzyme inhibition was mostly noncompetitive. Estimation of nNOS structure by fluorescence spectroscopy indicated that binding of the peptides to CaM led to a gradual unfolding of enzyme structure as levels of the fractions were increased. We concluded that the flaxseed protein‐derived peptides may be used as ingredients for the formulation of therapeutic foods.
Correlating chemical structure and physical properties of vegetable oil esters
Authors: Rodrigues Jorge de A. , Cardoso Fabianne de P. , Lachter Elizabeth R. , Estevão Luciana R. M. , Lima Edson , Nascimento Regina S. V.
Published: November 2006

The influence of FA ester chemical structures on the rheology and crystallization temperature of those compounds was evaluated using methyl, n‐butyl, n‐octyl, and 2‐ethyl‐1‐hexyl FA esters with different chain lengths and different degrees of unsaturation. The rheological properties were analyzed in a high‐precision rheometer at various temperatures, and the crystallization temperatures were determined by DSC. Esters produced from the esterification of pure FA and from the transesterification of vegetable oils (i.e., soybean, corn, linseed, and babassu coconut oils) were evaluated. The length of the FA chain was shown to have a marked influence on the viscosity and crystallization temperature of the systems, whereas branching affected only the crystallization temperature to a significant extent. The viscosity and crystallization temperature of the systems were also influenced by the degree of unsaturation. One double bond was shown to increase viscosity, whereas two or three double bonds caused a decrease in the viscosity of the systems. Unsaturation lowered the crystallization temperature in all cases, regardless of the number of double bonds. From all the oils studied, methyl esters from babassu coconut oil presented the lowest crystallization temperatures.
A simple method to measure lipase activity in wheat and wheat bran as an estimation of storage quality
Authors: Rose Devin J. , Pike Oscar A.
Published: November 2006

The purpose of this research was to develop a simple method for measuring lipase activity as an indicator of wheat and wheat bran storage quality. This simplified method does not require the separation or purification of lipase. Optimal conditions for lipase activity measurements were determined by varying the substrate (olive oil) and water concentrations, temperature, and incubation time. Following incubation, FFA were quantified spectrophtometrically using a copper soap assay, and lipase activity was expressed as units/gram (U/g), where 1 U was defined as the microequivalents of oleic acid liberated per hour. The method was tested on one commercial and four pure wheat cultivars. The lipase activity was also correlated with the development of FFA during actual storage of heat‐treated commercial bran. Lipase activity in wheat bran ranged from 2.17 to 9.42 U/g, and in whole kernel wheat from 1.05 to 3.54 U/g. Optimal olive oil and water concentrations were 0.4 to 0.8 mL and 0.15 to 0.20 mL per g of defatted sample, respectively. Optimal incubation temperature was 40°C, and incubation times of up to 8 h were linear. Lipase activity was highly correlated with the buildup of FFA in stored wheat bran (R2=0.97).
Improvement in the gas chromatographic resolution of petroselinate from oleate
Authors: Isbell Terry A. , Green Lindsay A. , DeKeyser Stephanie S. , Manthey Linda K. , Kenar James A. , Cermak Steven C.
Published: November 2006

In the extraction of oils from seeds of the genus Coriandrum, GC separations of petroselinate from oleate often gave poor resolution of these two isomers. Oleic and petroselinic acids were esterified with a series of alcohols (methanol, ethanol, 1‐propanol, 2‐propanol, 2‐methyl‐1‐propanol, 1‐butanol, 3‐methyl‐1‐butanol, and 2‐ethyl‐1‐hexanol). GC resolution of the Δ6 from the Δ9 and Δ11 octadecenoates was examined for all ester derivatives on a polar phase column. The Δ6 and Δ9 isomers were unresolved as methyl esters; however, the 2‐ethyl‐1‐hexyl esters gave baseline separation of all three isomers under temperature programming conditions. When isothermal conditions were optimized for each ester, separation of these isomers was possible with good resolution values (>89%) for all the alcohols except methanol, which had a partial resolution of 51%. The rates of esterification of all the alcohols were determined for reactions with both oleic acid and triolein using potassium hydroxide as the esterification catalyst. Methanol gave the largest rate constant in both acid and oil esterification reactions with a rate constant 10‐fold better than all of the other alcohols. Based on rates of reaction, resolution of petroselinate from oleate, and removal of residual alcohol, the ethyl ester derivative appears to be the best choice for seed oils containing petroselinic acid.
Purification and identification of rice bran oil fatty acid steryl and wax esters
Authors: Gunawan Setiyo , Vali Shaik Ramjan , Ju Yi‐Hsu
Published: November 2006

Fatty acid steryl esters (FASE) and wax esters (WE) of rice bran oil (RBO) have potential applications in cosmetic, nutraceutical, and pharmaceutical formulations. FASE and WE were extracted from RBO by a modified Soxhlet extraction using hexane as the solvent. FASE and WE were then separated by storage in acetone at 10°C for 24 h. The FASE fraction was further purified by silica, gel column chromatography. The contents and compositions of FASE and WE, as well as their saponified products, were identified by GC and GC‐MS. The identification of FASE and WE was carried out by comparing the retention time of GC peaks and mass spectral analysis with standards synthesized in our laboratory. FASE and WE accounted for ca. 4.0% of crude RBO, of which 2.8–3.2% and 1.2–1.4% are FASE and WE, respectively. GC‐MS of FASE showed five major peaks. Major FA in the FASE fraction were linoleic acid and oleic acid, which were esterified with 4‐desmethyl, 4‐monomethyl, and 4,4‐dimethyl sterols. The contents of 4‐desmethylsterol, 4‐monomethylsterol, and 4,4‐dimethylsterol esters in crude RBO were 76.1, 8.7, and 15.1%, respectively. WE of RBO consisted of both even and odd carbon numbers ranging from C44 to C64. The major constituents were, saturated esters of C22 and C24 FA and C24 to C40 aliphatic alcohols, with C24 and C30 being the predominant FA and fatty alcohol, respectively. The advantages of using a modified Soxhlet extraction over column chromatography are less solvent usage and larger sample size per batch with shorter operation time.
Evaluation of the CP‐Sil 88 and SP‐2560 GC columns used in the recently approved AOCS official method Ce 1h‐05: Determination of cis‐, trans‐, saturated, monounsaturated, and polyunsaturated fatty acids in vegetable or non‐ruminant animal oils and fats by capillary GLC method
Authors: Nimal Ratnayake W. M. , Hansen Steven L. , Kennedy Michael P.
Published: November 2006

The AOCS Official Method Ce 1h‐05 was recently approved at the 96th AOCS Annual Meeting (2005) by the Uniform Methods Committee as the official method for determining cis and trans FA in vegetable or non‐ruminant fats and oils. A series of experiments was undertaken using a margarine (hydrogenated soybean oil) sample containing approximately 34% total trans FA (28% 18∶1 trans, 6% 18∶2 trans, and 0.2% 18∶3 trans), a low‐trans oil (ca. 7% total trans FA), and a proposed system suitability mixture (12∶0, 9c−18∶1, 11c−18;1, 9c,12c,15c−18∶3, 11c−20∶1, and 21∶0) in an effort to evaluate and optimize the separation on the 100‐m SP‐2560 and CP‐Sil 88 flexible fused‐silica capillary GC columns recommended for the analysis. Different carrier gases and flow rates were used during the evaluation, which eventually lead to the final conditions to be used for AOCS Official Method Ce 1h‐05.
Structuring of edible oils by mixtures of γ‐oryzanol with β‐sitosterol or related phytosterols
Authors: Bot Arjen , Agterof Wim G. M.
Published: November 2006

The relation between molecular structure of oil‐structuring agents and their gel‐forming capability was investigated for mixtures of the phytosterol ester γ‐oryzanol with a series of phytosterols. Dihydrocholesterol, cholesterol, β‐sitosterol, and stigmasterol were found to form firm transparent gels with γ‐oryzanol in sunflower oil under the conditions used in this work. The mixture of β‐sitosterol with γ‐oryzanol in sunflower oil does not gel immediately on cooling, but mechanical agitation such as shear promotes gelling. Gels that are formed immediately after cooling show a higher modulus than gels for which there is a time delay between cooling and agitation (150 vs. 100 kPa). The effect of oscillatory shear parameters (amplitude, frequency) is small, as long as the yield stress of the gel is not exceeded. The gels withstand compression very well (up to deformations of 10%), but yield at very small deformations. The enthalpy of melting of the solid phase is estimated to be 26±4 kJ/mol, putting it in the same range as for certain fibrillar steroid‐derived organogels.
Elastohydrodynamic properties of seed oils
Authors: Biresaw G.
Published: November 2006

The film‐forming properties of canola (CAN), soybean (SBO), and jojoba (JO) seed oils under elastohydrodynamic (EHD) conditions were investigated to determine whether differences in their chemical and physical properties affect their EHD properties. Polyalphaolefin (PAO), whose EHD properties have been reported before, was used as the reference synthetic oil. The effect of measurement variables (speed, load, and temperature) on the film thickness of seed oils was consistent with that predicted by EHD theory. Pressure‐viscosity coefficients (pvc) calculated from film thickness data at 40°C showed a steady‐state value until about 50 nm film thickness, from which the following mean and SD values for CAN, SBO, and JO were obtained (GPa−1): 10.0±0.9,7.6±0.7, and 7.3±0.5, respectively. However, further reduction of film thickness below about 50 nm resulted in an increase of pvc for CAN, but a decrease of pvc for SBO and JO.
Elucidation of acyl migration during lipase‐catalyzed production of structured phospholipids
Authors: Vikbjerg Anders F. , Mu Huiling , Xu Xuebing
Published: November 2006

Elucidation of acyl migration was carried out in the Lipozyme RM IM (Rhizomucor miehei)‐catalyzed transesterification between soybean phosphatidylcholine (PC) and caprylic acid in solvent‐free media. A five‐factor response surface design was used to evaluate the influence of five major factors and their relationships. The five factors—enzyme dosage, reaction temperature, water addition, reaction time, and substrate ratio—were varied on three levels together with two star points. Enzyme dosage, reaction temperature, and reaction time showed increased effect on the acyl migration into the sn‐2 position of PC, whereas increased water addition and substrate ratio had no significant effect in the ranges tested. The best‐fitting quadratic response surface model was determined by regression and backward elimination. The coefficient of determination (R2) was 0.84, which indicates that the fitted quadratic model has acceptable qualities in expressing acyl migration for the enzymatic transesterification. Correlation was observed between acyl donor in the sn‐2 position of PC and incorporation of acyl donor into the intermediate lysophosphatidylcholine. Furthermore, acyl migration into the sn‐2 position of PC was confirmed by TLC‐FID, as PC with caprylic acid was observed on both positions. Under certain conditions, up to 18% incorporation could be observed in the sn‐2 position during the lipase‐catalyzed transesterification.
Synthesis of polyfunctional fatty amines from sophorolipid‐derived 17‐hydroxy oleic acid
Authors: Zerkowski Jonathan A. , Solaiman Daniel K. Y.
Published: November 2006

A series of mono‐ and diamines and one triamine have been prepared using methyl 17‐hydroxy oleate as the common starting material. The 17‐hydroxy oleate is an abundant bioderived material obtained from acid alcoholysis of sophorolipids, which in turn are produced by fermentation of agricultural by‐products. Incorporation of the amino unit(s) can be selectively performed at either end of the chain or at its middle. The chief synthetic reactions used are allylic bromination, Curtius rearrangement, and the Mitsunobu reaction. These fatty amines also possess functionality such as hydroxy groups, carboxylic acids, and C−C double bonds. The amines are isolated in protected form using a variety of protecting groups, the identities of which can be selected on the basis of the intended use of the amine. These novel compounds will be of interest in the preparation of highly functionalized polymers and surfactants, among other areas.
Metathesis of unsaturated fatty acids: Synthesis of long‐chain unsaturated‐α,ω‐dicarboxylic acids
Authors: Ngo Helen L. , Jones Kerby , Foglia Thomas A.
Published: November 2006

The self‐metathesis of readily available monounsaturated FA has the potential of being an important pathway for the synthesis of symmetrical long‐chain unsaturated‐α,ω‐dicarboxylic acids (C18−C26). Previous studies on the self‐metathesis of monounsaturated FA esters using ruthenium catalysts in solution, however, suffered from low conversions as a result of the thermodynamic control of the reaction. We have found that the second‐generation Grubbs catalyst can effectively catalyze the solvent‐free self‐metathesis of monounsaturated FA of varying purity (from 90 to 99%) to afford two important products—monounsaturated dicarboxylic acids and hydrocarbons—in very high molar conversions (>80%). This solvent‐free self‐metathesis reaction also works for monounsaturated FA containing additional functional groups. Reactions were conducted at catalyst loadings as low as 0.005 mol%, and turnover numbers as high as 10,800 could be obtained. This discovery represents an attractive approach to the large‐scale production of useful monounsaturated‐α,ω‐dicarboxylic acids and long‐chain unsaturated hydrocarbons by means of this solvent‐free ruthenium‐catalyzed self‐metathesis of readily available monounsaturated FA.
Epoxidation of karanja (Pongamia glabra) oil by H2O2
Authors: Goud Vaibhav V. , Pradhan Narayan C. , Patwardhan Anand V.
Published: November 2006

Epoxidation of karanja oil (KO), a nondrying vegetable oil, was carried out with peroxyacetic acid that was generated in situ from aqueous hydrogen peroxide and glacial acetic acid. KO contained 61.65% oleic acid and 18.52% linoleic acid, respectively, and had an iodine value of 89 g/100 g. Unsaturated bonds in the oil were converted to oxirane by epoxidation. Almost complete epoxidation of ethylenic unsaturation was achieved. For example, the iodine value of the oil could be reduced from 89 to 19 by epoxidation at 30°C. The effects of temperature, hydrogen peroxide‐to‐ethylenic unsaturation ratio, acetic acid‐to‐ethylenic unsaturation ratio, and stirring speed on the epoxidation rate and on oxirane ring stability were studied. The rate constant and activation energy for epoxidation of KO were 10−6 L·mol−1·s−1 and 14.9 kcal·mol−1, respectively. Enthalpy, entropy, and free energy of activation were 14.2 kcal·mol−1, −51.2 cal·mol−1·K−1, and 31.1 kcal·mol−1, respectively. The present study revealed that epoxides can be developed from locally available natural renewable resources such as KO.