bluuebunny/crossref_metadata_2025_split huggingface dataset:
Antioxidant and radical‐scavenging activities of buckwheat seed components
Authors: Przybylski R. , Lee Y. C. , Eskin N. A. M. 
Published: May 2007

AbstractThe search for endogenous components in food ingredients exhibiting antioxidant activity has been intensified in order to eliminate synthetic antioxidants. Tocopherols are widely used as natural antioxidants, although their protective ability is not always sufficient. Buckwheat seed components were evaluated for antioxidant and free radical‐scavenging activities using solvents of different polarities to isolate components from hulls and groats. Components extracted from buckwheat hulls were pro‐oxidant in canola oil. Antioxidant activity of extracts from buckwheat groats increased when more polar solvents were used for extraction. The highest activity was observed for the methanolic extract. Radical‐scavenging activity of buckwheat extracts was analyzed with DPPH (2,2‐diphenyl‐2‐picryl‐hydrazyl). This activity increased when the more polar solvents were used for extraction, with the highest activity observed for the methanolic extract. It was also observed that the radical scavenging effectiveness of extracts was concentration dependent. Analysis revealed the presence of tocopherols in the hexane extract, while methanolic extracts were rich in phenolic acids and flavonoids.
Relation of fat bloom in chocolate to polymorphic transition of cocoa butter
Authors: Bricknell J. , Hartel R. W. 
Published: May 2007

AbstractA special chocolate with spray‐dried sugar (50:50 w/w sucrose/20 Dextrose Equivalent corn syrup solids) was made to study the polymorphic changes in cocoa butter crystals using X‐ray diffraction. Anhydrous milk fat (AMF) and high‐, middle‐, and low‐melting milk fat fractions were used to replace 2% (w/w) of cocoa butter. Chocolates were tempered, and the consistency of temper among chocolate samples was verified by a temper meter. Chocolates were cycled between 19 and 29°C at 6‐h intervals to induce fat bloom. The special chocolates were analyzed by X‐ray spectroscopy and colormeter.X‐ray analysis on the special chocolates showed polymorphic transition from the βV to the βVI form of cocoa butter. After a lag phase, the percentage of the βVI form rapidly increased. However, the sample made with the high‐melting milk fat fraction transformed slowly to βVI. Visual bloom appeared rapidly on the special chocolates made with AMF, middle‐ and low‐melting fractions, whereas visual bloom was very slow to appear on the special chocolates made with high‐melting milk fat fraction and on the cocoa butter control. The commercial chocolate responded consistently; the control bloomed rapidly, the AMF exhibited some bloom resistance, and the high‐melting fraction inhibited bloom. Despite the βV to βVI transition, the control chocolates with amorphous sugar did not bloom. Since the only difference in the chocolates was sugar microstructure, differences in bloom formation were caused by the microstructure, not the polymorphic transition.
Thermal analysis of isothermal crystallization kinetics in blends of cocoa butter with milk fat or milk fat fractions
Authors: Metin Serpil , Hartel Richard W. 
Published: May 2007

AbstractThe kinetics of isothermal crystallization of binary mixtures of cocoa butter with milk fat and milk fat fractions were evaluated by applying the Avrami equation. Application of the Avrami equation to isothermal crystallization of the fats and the binary fat blends revealed different nucleation and growth mechanisms for the fats, based on the Avrami exponent. The suggested mechanism for cocoa butter crystallization was heterogeneous nucleation and spherulitic growth from sporadic nuclei. For milk fat, the mechanism was instantaneous heterogeneous nucleation followed by spherulitic growth. For milk fat fractions, the mechanism was high nucleation rate at the beginning of crystallization, which decreased with time, and plate‐like growth. Addition of milk fat fractions did not cause a significant change in the suggested nucleation and growth mechanism of cocoa butter.
Physico‐chemical characteristics of palm‐based oil blends for the production of reduced fat spreads
Authors: Lida Habi Mat Dian Noor , Ali A. Rahim Md 
Published: May 2007

AbstractThe effect of blending and interesterification on the physicochemical characteristics of fat blends containing palm oil products was studied. The characteristics of the palm‐based blends were tailored to resemble oil blends extracted from commercial reduced fat spreads (RFS). The commercial products were found to contain up to 20.4% trans fatty acids, whereas the palm‐based blends were free of trans fatty acids. Slip melting point of the blends varied from 26.0–32.0°C for tub, and 30.0–33.0°C for block RFS. Solid fat content at 5 and 10°C (refrigeration temperature), respectively, varied from 10.9–19.7% and 8.5–17.6% for tub, and 28.2–38.6% and 20.8–33.5% for block RFS. Melting enthalpy of the tub RFS varied from 35.0–54.3 J/g and that of block RFS varied from 58.0–75.4 J/g. To produce block RFS, 65% palm oil (PO) and 18% palm kernel olein (PKOo) could be added in a ternary blend with sunflower oil (SFO), but only 47% PO and 10% PKOo are suggested for tub RFS. Higher proportion of PO, i.e., 72% for block RFS and 65% for tub RFS, could be used after the ternary blend was interesterified. Although a ternary blend of palm olein (POo)/SFO/PKOo was not suitable for RFS formulation, after interesterification as much as 90% POo and 26% PKOo could be used in the block RFS formulation. For tub RFS a maximum of 30% POo was found suitable.
The influence of chemical interesterification on the physicochemical properties of complex fat systems. 3. Rheology and fractality of the crystal network
Authors: Marangoni Alejandro G. , Rousseau Dérick 
Published: May 2007

AbstractChemically interesterified and noninteresterified lard‐canola oil (LCO) and palm oil‐soybean oil blends ranging from 100% hardstock to 50%:50% hardstock/vegetable oil (w/w) were evaluated for hardness index (HI) using cone penetrometry and viscoelastic properties, such as shear storage modulus G′, using controlled‐stress rheometry. The HI and G′ of palm oil decreased upon addition of soybean oil, and chemical interesterification did not affect the HI or G′ of palm oil or palm oil‐soybean oil blends. The HI and G′ of lard decreased upon addition of canola oil, while chemical interesterification led to increases in both the HI and G′ of lard and LCO blends. All these effects were nonsolid fat content‐related, since solid fat content did not change substantially upon chemical interesterification. The microstructure of the fat crystal network in lard and palm oil was quantified rheologically using fractal analysis. Chemical interesterification did not affect the fractal dimension of the fat crystal networks in palm oil or lard (2.82 and 2.88, respectively). The rheological properties of the macroscopic systems were not affected by the spatial distribution of mass within their fat crystal networks. Moreover, our results suggest that the increases in G′ observed in lard upon chemical interesterification are potentially due to changes in the properties of the particles which make up the network (crystal habit).
The seed fatty acid composition and the distribution of Δ5‐olefinic acids in the triacylglycerols of some taxaceae (Taxus and Torreya)
Authors: Wolff Robert L. , Pédrono Frédérique , Marpeau Anne M. , Christie William W. , Gunstone Frank D. 
Published: May 2007

AbstractThe fatty acid compositions of the seeds from three Taxus (yew) species and one Torreya species belonging to the Taxaceae family [Taxus cuspidata (Japanese yew), T. chinensis (Chinese yew), T. baccata (English yew), and Torreya grandis (Chinese nutmeg yew)] have been established. These compositions were compared with those previously published for T. canadensis (Canadian yew) and Torreya nucifera. In Taxus species, as well as in Torreya species, Δ5‐olefinic acids are present in the seed lipids from all species analyzed. In Taxus, 5,9‐18:2 (taxoleic) acid is the prominent Δ5‐olefinic acid. It represents between 9.5 and 16.2% of total fatty acids. Other Δ5‐olefinic acids that occur in low amounts are 5,9,12‐18:3 (<3.5%), 5,11‐20:2 (<0.3%), 5,11,14‐20:3 (<2.2%), and 5,11,14,17‐20:4 (<0.3%) acids. In Torreya species, the major Δ5‐olefinic acid is 5,11,14‐20:3 (sciadonic) acid (between 6.7 and 11.2%). In contrast to Taxus species, the 5,9‐18:2 and 5,9,12‐18:3 acids are scarce in Torreya species: less than 0.1%. Also, the 9,12,15‐18:3 acid content is significantly lower in Torreya than in Taxus. The prominence of taxoleic acid among Δ5‐olefinic acids in the seed lipids is a unique characteristic of the genus Taxus that isolates it from all other Coniferophytes analyzed so far. However, this feature is not shared by other Taxaceae species, such as Torreya, and with regard to their seed fatty acid compositions, the family Taxaceae appears particularly heterogeneous. Our observations favor the hypothesis that in Gymnosperm seeds, there might exist two Δ5‐desaturases, one specific for unsaturated acids with a Δ9‐ethylenic bond (active in Taxus but not in Torreya), and the other specific for unsaturated acids with a Δ11‐ethylenic bond (active in Torreya but not in Taxus). Our data also highlight the importance of the elongase(s) in the metabolism of fatty acids in Gymnosperm seeds. 14‐Methylhexadecanoic acid, a habitual component of Pinaceae and Ginkgo biloba seed lipids, could not be detected in the Taxaceae studied here. 13C nuclear magnetic resonance spectroscopy of the oils from both genera has confirmed that Δ5‐olefinic acids are apparently excluded from the internal position of triacylglycerols, which is a characteristic common to all Gymnosperm species analyzed so far, and consequently of great antiquity in their life history.
Hydroxytyrosol and tyrosol as the main compounds found in the phenolic fraction of steam‐exploded olive stones
Authors: Fernández‐BolaɁos J. , Felizón B. , Brenes M. , Guillén R. , Heredia A. 
Published: May 2007

AbstractThe lignocellulosic by‐products, whole stones, and seed husks obtained from processing pitted table olives and oil olives were pretreated under various conditions of steam explosion, with and without previous acid impregnation. The various water‐soluble noncarbohydrate compounds generated during steam explosion, such as sugar degradation compounds (furfural and hydroxymethylfurfural), lignin degradation compounds (vanillic acid, syringic acid, vanillin, and syringaldehyde) and the simple phenolic compounds characteristic of olive fruit (tyrosol and hydroxytyrosol), were identified. The amount of hydroxytyrosol solubilized was higher than that of the other compounds, and increased with increasing steaming temperature and time. This suggests its presence as a structural component of the olive stone.
Identification of trans‐3,5‐dimethoxystilbene in commercial soy protein isolates
Authors: Boatright W. L. , St. Pyrek J. , Song J. , Crum A. D. 
Published: May 2007

AbstractA previously unidentified component of the lipid extracts from commercial soy protein isolates (SPI) was analyzed by gas chromatography‐mass spectrometry (GC‐MS), high resolution mass spectrometry (HRMS), ultraviolet‐visible spectroscopy, and GC‐Fourier transform infrared spectrometry (FTIR). All these data, together with mass spectra of derivatives obtained by hydrogenation, indicated the structure of an unsymmetrical dimethoxystilbene. Subsequently, standard trans‐3,5‐dimethoxystilbene, synthesized according to established procedures, was found to have identical retention times and spectra by GC‐MS and GC‐FTIR with the compound isolated from commercial SPI. Laboratory SPI prepared from Probst, Stressland, and Burlison variety soybeans contained no detectable amounts of either trans‐3,5‐dimethoxystilbene or dehydroabietinal.
Studies on lipid and fatty acid compositions of puffer livers from Indian coastal waters with seasonal variation
Authors: Hazra Alok K. , Ghosh Somiranjan , Banerjee Shivaji , Mukherjee Biswapati 
Published: May 2007

AbstractThe puffer fishes Chelonodon patoca, Sphaeroides oblongus, Lagocephalus lunaris, and L. inermis of Indian coastal waters are wasted in huge quantity. The livers of these fishes were investigated for their lipid contents and fatty acid compositions in different seasons. It was found that monsoon season is the suitable time to obtain the maximal lipids (40.1–48.8%) from their livers, an amount similar to cod liver lipid content (39.5–55.0%). The fatty acids were mostly saturates and monoenes (60–70%). Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) concentrations (7–12%) were high during monsoon season. Neutral lipids were the predominant lipid class (>80%) and comprised triglycerides (277–674 mg/g) and cholesterol (0.6–3.1 mg/g). Quality indices of puffer liver lipids, e.g., specific gravity, refractive index, acid value, iodine value, saponification value and unsaponifiable matter, were evaluated. Puffer liver lipids were quantitatively and qualitatively comparable to other commercially important marine fish oils. The overall study suggests the possibility of future commercial utilization of liver lipids from puffer, an unconventional, cheap, and easily available source.
5α,8α‐Epidioxycholest‐6‐en‐3‐β‐ol from three cone snails of the Indian ocean
Authors: Aknin M. , Viracaoundin I. , Faure R. , Gaydou E. M. 
Published: May 2007

AbstractThree cone snail species (Conus ebraeus, C. leopardus, C. tessulatus, family Conidae) have been investigated for their sterolic fraction. Besides cholesterol, 5α,8α‐epidioxycholest‐6‐en‐3‐β‐ol has been isolated from each species and the structure determined using two‐dimensional nuclear magnetic resonance. The occurrence of 5α,8α‐epidioxycholest‐6‐en‐3‐β‐ol in high amounts in the crude extract (0.5%), constitutes an interesting source of this compound.
Physical refining of rice bran oil in relation to degumming and dewaxing
Authors: De B. K. , Bhattacharyya D. K. 
Published: May 2007

AbstractPhysical refining of rice bran oil (RBO) with acidity between 4.0 and 12.4% has been investigated in relation to degumming and dewaxing pretretments. It appears that physical refining after combined low‐temperature (10°C) degumming‐dewaxing produces good‐quality RBO with respect to color, free fatty acid, oryzanol, and tocopherol content.
Differential extraction of eleostearic acid‐rich lipid‐protein complexes in tung seeds
Authors: Dyer John M. , Tang Fuqiang , Chapital Dorselyn C. , Lax Alan R. , Shepherd Hurley S. , Shih Ding S. , Pepperman Armand B. 
Published: May 2007

AbstractLipid‐protein complexes were identified in the 104,000×g supernatant fraction of developing tung seeds. Incubation of this fraction with linoleoyl‐CoA promoted an increase of chloroform‐extractable lipids in a time‐dependent manner. High‐performance liquid chromatography analysis indicated that the extracted lipids were similar to mature tung oil triglycerides. Differential extraction using chloroform or chloroform/methanol indicated that linoleoyl‐CoA promoted extraction of pre‐existing lipids rather than de novo synthesis. An increase in extractable lipids was also observed after incubation with proteinase K. Isolation of lipid‐protein complexes by sucrose density centrifugation and analysis of proteins by gel electrophoresis revealed several proteins specifically associated with this lipid fraction.
Effect of fatty acid positional distribution and triacylglycerol composition on lipid by‐products formation during heat treatment: I. Polymer formation
Authors: Martin J. C. , Dobarganes M. C. , Nour M. , Marquez‐Ruiz G. , Christie W. W. , Lavillonnière F. , Sébédio J.L 
Published: May 2007

AbstractEffects of the fatty acid positional distribution and of the triacylglycerol (TG) composition on polymerization of TG during heat treatment were studied. Diacid TG molecules, acylated only with linoleic acid or linolenic acid along with palmitic acid, and positioned either in the central position (PLP and PLnP, respectively) or in one of the two outer positions (PPL and PPLn, respectively) were synthesized. Monoacid TG, i.e., trilinolein and trilinolenin, were also synthesized and mixed with tripalmitin in a 1:2 ratio. These model TG were also compared to TG models that consisted of a canola oil and its randomized counterpart, whose fatty acid positional distribution and TG composition were determined by means of high‐performance liquid chromatography (HPLC). After heating, the polymer content and composition were evaluated by HPLC‐size exclusion chromatography. Both pure TG and the canola oil models showed that acylation of polyunsaturated acids in the central position was protective against polymerization, although the effect was mainly observed with linolenic acid. The synthetic‐TG study showed that the monoacid TG species exhibited higher sensitivity toward polymerization than the diacid species. The slight differences in the TG species between both canola oils did not allow observation of such a relationship with regard to TG composition.
Effect of fatty acid positional distribution and triacylglycerol composition on lipid by‐products formation during heat treatment: II. Trans isomers
Authors: Martin J. C. , Nour M. , Lavillonnière F. , Sébédio J.L 
Published: May 2007

AbstractThis study examined the effect of the fatty acid positional distribution and of the triacylglycerol (TG) composition on heat‐induced trans isomerization of linoleic and linolenic acids. For this, we synthesized diacid TG molecules that were acylated only with linoleic acid (L) or with linolenic acid (Ln) along with palmitic acid (P). The fatty acid of interest was positioned either in the central position (PLP and PLnP, respectively) or in one of the two outer positions (PPL and PPLn, respectively). Monoacid TG, i.e., trilinolein and trilinolenin, were also synthesized and mixed with tripalmitin in a 1:2 ratio. This model TG was also compared to another TG model, which consisted of a canola oil and its randomized counterpart whose fatty acid positional distribution and TG composition were determined by means of high‐performance liquid chromatography. After heating, the content of trans isomers was determined by gas‐liquid chromatography with a polar capillary column. In model TG, polyunsaturated fatty acids in monoacid TG (LLL and LnLnLn) exhibited the highest degree of isomerization, compared to diacid TG, and this effect was greatest at 220°C. At this temperature, an effect of the TG structure was observed only with linolenic acid. In that situation, 18:3n‐3 acylated in the central position of the TG molecule (PLnP) displayed the highest sensitivity to trans geometrical isomerization. Although to a lesser extent, the same trends as for the pure TG model were observed with the canola oil model with regard to the influence of the fatty acid positional distribution and TG molecular species.
Fatty acid composition and contents of trans monounsaturated fatty acids in frying fats, and in margarines and shortenings marketed in Denmark
Authors: Ovesen Lars , Leth Torben , Hansen Kirsten 
Published: May 2007

AbstractThis study examined trans monounsaturated fatty acid contents in all margarines and shortenings marketed in Denmark, and in frying fats used by the fast‐food restaurants Burger King and McDonald's. Trans C18:1 content was 4.1±3.8% (g per 100 g fatty acids) in hard margarines, significantly higher than the content in soft margarines of 0.4±0.8%. Shortenings had an even higher content of trans C18:1, 6.7±2.3%, than the hard margarines. Margarines and shortenings with high contents of long‐chain fatty acids had about 20% total trans monoenoic of which close to 50% were made up of trans long‐chain fatty acids. Both fast‐food frying fats contained large amounts of trans C18:1, 21.9±2.9% in Burger King and 16.6±0.4% in McDonald's. In Denmark the per capita supply of trans C18:1 from margarines and shortenings and frying fats has decreased steadily during recent years. The supply of trans C18:1 from margarines and shortenings in the Danish diet is now 1.1 g per day.
Effects of oilseed storage proteins on aflatoxin production by aspergillus flavus
Authors: Mellon Jay E. , Cotty Peter J. 
Published: May 2007

AbstractPotential involvement of seed storage proteins in susceptibility to aflatoxin contamination was assessed with in vitro tests. Initially, two oilseed storage proteins [cottonseed storage protein (CSP) and zein] were compared with bovine serum albumin (BSA) and collagen. Supplementation of a complete defined medium with either oilseed storage protein resulted in significantly more aflatoxin production by Aspergillus flavus than supplementation with either BSA or collagen. Little or no aflatoxin was produced when either BSA, CSP, or zein was employed (at 0.5%) as both the sole carbon and the sole nitrogen source. Media with collagen (0.5%) as the sole nitrogen and carbon source supported aflatoxin production similar to the complete defined medium. Although lower than levels observed with defined medium, aflatoxin production increased with both increasing CSP concentration (0 to 2.0%) and increasing zein concentration (0 to 6.0%) when these proteins served as both the sole carbon and sole nitrogen source. Denaturing polyacrylamide gel electrophoresis and protease activity assays indicated that fungal acquisition of protein carbon was probably via hydrolysis mediated by the 35 kD metalloprotease of A. flavus. Media lacking nitrogen but containing sucrose (5.0%) and supplemented with either zein (1.7%) or CSP (2.0%) supported three‐ to eightfold more aflatoxin production than the complete defined medium. The results suggest seed storage proteins, when present with an accessible carbon source, may predispose oilseed crops to support production of high levels of aflatoxins by A. flavus during seed infection.
Determination of unsaturated fatty acid composition by high‐resolution nuclear magnetic resonance spectroscopy
Authors: Miyake Yuko , Yokomizo Kazuhisa , Matsuzaki Narihide 
Published: May 2007

AbstractHigh‐resolution nuclear magnetic resonance (NMR) spectroscopy provides useful data for analyzing fatty acid compositions of edible vegetable oils. Quantitation of each fatty acid was carried out by evaluation of particular peaks. According to the 1H NMR method, terminal methyl protons, divinyl protons, and allyl protons are useful to calculate linolenic acid, linoleic acid, and oleic acid, respectively. The ω‐2 carbon, divinyl carbon, and allylic carbons were used for calculation of these acids by the 13C NMR method. Compositional results obtained by NMR coincided well with those of the conventional gas chromatography (GC) method. Results from 13C NMR were in better agreement with those from GC than were the results obtained by the 1H NMR method.