bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

AbstractSupercritical 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

AbstractThe 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

AbstractThe 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

AbstractLiquid 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

AbstractElectron 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

AbstractThis 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

AbstractThe 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

AbstractLipid 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

AbstractThe 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

AbstractUltrafiltration 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

AbstractIn 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

AbstractThe 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

AbstractStudies 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

AbstractAn 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

AbstractFish 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

AbstractA 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

AbstractDuring 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.