bluuebunny/crossref_metadata_2025_split huggingface dataset:
Odor significance of undesirable degradation compounds in heated triolein and trilinolein
Authors: Neff W. E. , Warner K. , Byrdwell W. C. 
Published: November 2006

AbstractTo better understand production of undesirable or negative odors such as fruity, plastic, and waxy that are characteristic of higher oleic acid‐containing oils, model heated oil systems of triolein and trilinolein were studied. Identification of the odor significance of volatile compounds produced by fractionated and nonfractionated triolein and trilinolein was done by purge and trap‐gas chromatography‐ion trap mass spectrometry‐olfactometry. The predominant odors of the triolein heated 1, 3, and 6 h at 190°C were fruity and plastic, with other negative odors of acrid and grassy. Some of the volatile compounds that produced negative odors in heated triolein, in order of increasing concentration, were hexanal (grassy), octanal (fruity), (E)‐2‐decenal (plastic), nonanal (fruity), and (E)‐2‐undecenal (plastic). Some of the negative odor compounds in trilinolein heated for 1, 3 and 6 h, in order of increasing concentration, included (E)‐2‐nonenal (plastic), pentanal (grassy), and hexanal (grassy). However, the amount of volatile compounds produced and the intensity levels of the odors were lower in trilinolein than in triolein. Formation of many of the volatiles was explained after identification of the volatile precursors, including epoxy, keto, and dimer oxidation products that were produced during heating.
A simple HPLC method for the simultaneous analysis of phosphatidylcholine and its partial hydrolysis products 1‐ and 2‐acyl lysophosphatidylcholine
Authors: Adlercreutz Dietlind , Wehtje Ernst 
Published: November 2006

AbstractA simple HPLC method for the simultaneous analysis of phosphatidylcholine (PC), 1‐acyl lysophosphatidylcholine (1‐acyl LPC), and 2‐acyl lysophosphatidylcholine (2‐acyl LPC) with refractive index detection is described. The separation of these three compounds was achieved on a Waters (Milford, MA) Spherisorb amino phase column using a mixture of ethanol and an aqueous oxalic acid solution as eluent. The optimal mixture of ethanol to oxalic acid solution was 92∶8 (vol/vol). PC and the two regioisomers of LPC eluted within 15 min. The calibration curves were linear in a concentration range from 0.05 to 2.5 mM. Natural PC or LPC eluted in a single peak, despite the diversity in the fatty acid composition. There was no rearrangement between 1‐acyl LPC and 2‐acyl LPC during analysis or storage in ethanol within 23 h. This method is thus especially suitable for studying reactions on PC and acyl migration in LPC.
Measurement of particle size distribution of tripalmitin crystals in a model solution using a laser diffraction method
Authors: Fitzgerald Andrea M. , Barnes O. John , Smart Ian , Wilson D. Ian 
Published: November 2006

AbstractThe form and size distribution of tripalmitin (PPP) crystals formed by quenching a solution in a batch crystallizer have been studied using scanning electron microscopy and a laser diffraction technique. Although the accuracy of the laser technique for particle sizing was affected by the nonsphericity of the crystals, the technique proved to be effective and very reproducible. Crystals recovered by filtration and sonication for laser sizing exhibited markedly different particle size distributions (PSD) and shapes compared to those prepared using another standard route, namely, suspension in butanol and centrifugation. Solutions of 2–10 wt% PPP in a paraffin solvent were crystallized at 25–40°C and displayed two ranges of behavior: (i) rapid growth under strongly supersaturated conditions, yielding narrow PSD of plate and needle‐like crystals; and (ii) slow growth in the metastable regime, yielding spherulitic aggregates of platelets that broke down under sonication during preparation for laser sizing. Suspension in alcohol followed by centrifugation yielded aggregates that did not break down under sonication, indicating that the sample preparation route affected the result of the analysis.
Thin‐film test to investigate liquid oxypolymerization of nonvolatile analytes: Assessment of vegetable oils and biodegradable lubricants
Authors: Asadauskas Svajus , Erhan Sevim Z. 
Published: November 2006

AbstractA thin‐film oxidation test was developed to investigate liquid oxypolymerization of nonvolatile analytes. Gel permeation chromatography (GPC) showed that the test delivered the required degree of oxidation with better than ±5% accuracy. The following oils were ranked according to their decreasing resistance to oxypolymer formation at 150°C: 90% oleic sunflower oil, triolein, meadowfoam oil, castor oil, canola oil, lesquerella oil, and soybean oil. Higher degrees of oxidation demonstrated the occurrence of oxidative gelation. Oxypolymerization tendencies of hydraulic fluids based on canola and rapeseed oils were comparable to those of canola oil without additives. The relative amount of C‐C polyunsaturation present in the fatty acid chain was a major differentiating factor. However, oxidation inhibitors also reduced the rates of oxypolymerization, as demonstrated by sunflower oil‐based hydraulic fluid. Canola and rapeseed lubricants needed better oxypolymerization control.
Synthesis of Δ2‐Isoxazoline fatty acid ester heterocycles
Authors: Kenar James A. , Erhan Sevim Z. 
Published: November 2006

AbstractFatty ester Δ‐2 heterocycles were prepared in good yields and excellent regioselectivity from 1,3‐dipolar cycloaddition reactions between methyl 10‐undecenoate and nitrile oxides. This methodology provides convenient access to the methyl esters of margaric (4b) and stearic (4c) acids in 63–66% yield that contain the isoxazoline heterocycle between C‐10 and C‐12. These fatty heterocycle compounds are synthesized in a one‐pot sequence in which methyl 10‐undecenoate is used to trap the reactive nitrile oxide intermediates that are generated by reacting aldoximes with aqueous sodium hypochlorite and a catalytic amount of triethylamine or by directly reacting hydroximic acid chlorides with a stoichiometric amount of base. The fatty ester Δ2‐isozazoline heterocycles represent a versatile synthon that may be useful to obtain oleochemicals with potentially new and interesting properties not easily accessible by other methods.
Supercritical fluid extraction of encapsulated oil products
Authors: Shih F. , Daigle K. 
Published: November 2006

AbstractStandard methods of oil analysis, for example, Soxhlet extraction and supercritical fluid extraction (SFE), were ineffective for recovering oil from encapsulated food products. Efforts were made to enhance SFE of the oil for these products. Samples were hydrated and heated, which helped to break down the encapsulating structure. In addition, extra diatomaceous earth was needed to absorb and disperse the added water. Optimal extraction conditions were established, and quantitative extraction of oil was achieved for various laboratory‐prepared and commercially encapsulated food products.
Enzyme‐assisted aqueous extraction of peanut oil
Authors: Sharma Aparna , Khare S. K. , Gupta M. N. 
Published: November 2006

AbstractEnzyme‐assisted aqueous extraction of oil from oilseeds is a relatively recent technique. In the present study, peanut oil was extracted under optimized aqueous extraction conditions using Protizyme™, which is predominantly a mixture of acid, neutral, and alkaline proteases. The optimal conditions were: enzyme concentration of 2.5% (w/w) in 10 g of peanut seeds, pH 4.0, 40°C, and 18 h incubation with constant shaking at 80 rpm. Centrifuging the mixture at 18,000 × g for 20 min separated the oil with a recovery of 86–92%. The merits of this process over existing solvent extraction and/or mechanical pressing methods are discussed.
An evaluation of supercritical fluid extraction as an analytical tool to determine fat in canola, flax, solin, and mustard
Authors: Barthet Véronique J. , Daun James K. 
Published: November 2006

AbstractSupercritical fluid extraction (SFE) with carbon dioxide was used to extract oil from soft oilseeds (flax, solin, canola, and mustard). Oil content determinations from the SFE method AOCS Am 3–96, with and without ethanol as a modifier, were compared to results obtained with an exhaustive extraction using petroleum ether (FOSFA as in AOCS Am 2–93). Without the modifier, oil recoveries using SFE were 10 to 15% lower than oil contents by the FOSFA method for the flax and canola samples. For mustard, the oil recoveries by SFE were about 20 to 30% lower than oil contents by the FOSFA method. In the presence of the modifier, oil recoveries for flax and canola were about 3% lower than the FOSFA recoveries. Varying the time, temperature, and amount of modifier (ethanol) showed that recoveries increased with time, pressure, temperature, and amount of modifier independently of the oilseeds tested. Kinetics of the SFE extraction showed that the oil recoveries increased with the extraction time and reached a plateau after 60 min. Multiple extractions (2×30 min), however, gave better recoveries than a single extraction for the same amount of time (60 min). The best results were obtained using multiple extractions without modifier or a combination of multiple extractions first without and then with 15% modifier. Under these last two conditions, oil recoveries were close to 100% for flax, solin, and canola, but mustard oil recoveries were still 10% lower than recoveries using the FOSFA method. Mustard samples gave the lowest oil recovery from SFE when compared to FOSFA method recoveries whatever conditions were tested, suggesting a matrix effect on the oil recovery. The acyl lipid content of the various extracts was studied using the sum of all FA expressed as TAG as a measure of acyl lipid extraction. The acyl lipid contents of the extracts were close to 100% when no modifier was used during the SFE. In the presence of modifier, the acyl lipid contents of the extracts were 10 to 15% lower than the results obtained without modifier. The amount of acyl lipid in the extract decreased as the quantity of modifier increased. This suggests that increasing the ethanol modifier increased the amount of polar compounds extracted without significantly increasing the total amount of lipids. The FA profiles were constant throughout the various extraction procedures.
One‐step methodology for the synthesis of FA picolinyl esters from intact lipids
Authors: Destaillats Frédéric , Angers Paul 
Published: November 2006

AbstractPicolinyl derivatives are used for structural determination of FA by GC‐MS. Although they provide reliable diagnostic fragments, the usual multistep methodologies applied for their preparation require TAG hydrolysis or acid chloride formation prior to picolinyl synthesis. These reaction conditions may result in the presence of artifact molecules in the samples and thus compromise analytical quality and accuracy. To address these problems, a rapid, simple and quantitative methodology for the synthesis of FA picolinyl esters from intact lipids was developed. It involves their transesterification under basecatalyzed conditions using 3‐potassiooxamethylpyridine in methylene chloride. The catalyst was prepared by proton exchange between potassium tert‐butoxide and anhydrous 3‐hydroxymethylpyridine. Mild reaction conditions allowed complete derivatization of TAG and phospholipids in 2 min at room temperature, and of FAME in 15 min at 45°C. The proposed procedure, which can be used on a routine basis, was applied to Ipomoae imperialis seed lipids and used to confirm occurrence of γ‐linoleic acid at a level of 0.9%.
Fast and accurate method for total 4‐desmethyl sterol(s) content in spreads, fat‐blends, and raw materials
Authors: Duchateau G. S. M. J. E. , Bauer‐Plank C. G. , Louter A. J. H. , van der Ham M. , Boerma J. A. , van Rooijen J. J. M. , Zandbelt P. A. 
Published: November 2006

AbstractPlant sterols are added as their FA esters to vegetable oil table spreads at levels of approximately 8% as a means to reduce blood cholesterol levels. A new chromatographic method was designed to quantify quickly the level of plant sterol FA esters in incoming (raw) materials and to monitor their processing and final product quality with respect to total sterol level. The method shows a significant improvement in elapsed time and thus labor cost over the classical methods for sterols published in normative references. This improvement was obtained together with high performance characteristics, as shown by the internal method validation for recovery and repeatability. Its validity and robustness were further tested and confirmed in an international collaborative test. The method allows monitoring of sterol content of raw materials, fat‐blends, and consumer products at the target level, with a range of 10% or less around this target. The calculated within‐ and between‐laboratory reproducibility were 0.680 and 1.194 w/w%, respectively, for sterol‐containing spreads. The results afforded by this method can be used for setting tight product specifications or to monitor trade between companies. We propose to add this new and fast method for total 4‐desmethyl sterol(s) to analytical method collections as an adjunct to methods already listed for more detailed sterol analysis.
Physical and textural characteristics of hydrogenated low‐erucic acid rapeseed oil and low‐erucic acid rapeseed oil blends
Authors: Danthine Sabine , Deroanne Claude 
Published: November 2006

AbstractLow‐erucic acid rapeseed oil (LERO) and hydrogenated low‐erucic acid rapeseed oil (HLERO) were blended in binary systems. The blends were then studied for their physical properties such as solid fat content, melting curves by DSC, textural properties, and polymorphism. Phase behavior diagrams were constructed from the DSC and X‐ray results, and isosolid diagrams were constructed from the NMR results. The mixture of HLERO and LERO displayed a monotectic behavior for all the storage time at 15°C. The aim of this work was to evaluate physical characteristics of binary blends of HLERO and nonydrogenated LERO in order to use only LERO and hardened LERO in bakery shortenings. The mixture of 60% HLERO and 40% LERO is suitable to use as a plastic shortening. This blend is β tending upon storage at 15°C. It could be used in pie crust applications.
Effect of a modified deep‐fat fryer on chemical and physical characteristics of frying oil
Authors: Negishi Hironori , Nishida Minoru , Endo Yasushi , Fujimoto Kenshiro 
Published: November 2006

AbstractWe designed a modified deep‐fat fryer (MDF) to have a smaller oil area (A) relative to depth or height (H) such that H/√A=0.93. The modification was intended to retard the thermal degradation of the frying oil and the production of waste oil. Frozen croquettes were fried in vegetable oil using the MDF (H/√A=0.93) and three conventional deep‐fat fryers (CDF1, H/√A=0.25; CDF2, H/√A=0.20; CDF3, H/√A=0.30) at 180°C for 72 h at 8 h/d. Frying oils were periodically collected, and their chemical and physical characteristics were examined. The acid value (AV) of frying oils used for 72 h in the MDF was lower than that for oils used in the CDF, although the AV was similar in all fryers until 32 h. The oil deep‐fried with MDF had a higher degree of color than that with CDF until 48 h. Polymerized materials and the carbonyl value of frying oil after heating 72h with MDF were lower than those with CDF. The residual tocopherol content of frying oil with MDF was 83% of the content in fresh oil, whereas with CDF the tocopherol contents were less than 63%. The oil consumption by MDF was less than that by CDF, although the turnover rate was higher in MDF than in CDF. These results suggest that during deep‐fat frying the MDF may retard the thermal deterioration of vegetable oils and generate less waste oil.
Enthalpies of mixing and heat capacities of mixtures containing alcohols and n‐alkanes with corn oil at 298.15 K
Authors: González C. , Resa J. M. , Concha R. G. , Goenaga J. M. 
Published: November 2006

AbstractEnthalpies of mixing for mixtures containing alcohols (methanol, ethanol, 1‐propanol, 2‐propanol, 1‐butanol, and 2‐butanol) plus corn oil or n‐alkanes (n‐hexane, n‐heptane, and n‐octane) plus corn oil were measured at 298.15 K and atmospheric conditions. The enthalpy was measured in the range of concentrations in which alcohols were miscible with the vegetable oil. Results were correlated by the Redlich‐Kister equation. The mixing of alcohols with corn oil was strongly endothermic, whereas values obtained for the binaries containing n‐alkanes were slightly endothermic. Thus, heat capacities were calculated for all the systems studied.
Rapid evaluation of olive oil quality by NIR reflectance spectroscopy
Authors: Mailer Rodney J. 
Published: November 2006

AbstractNIR spectroscopy calibrations have been developed for a range of quality parameters in olive oil, including FFA, PV, polyphenol content, induction time, chlorophyll, and the major FA. A set of 216 olive oil samples from throughout the Australian olive‐growing areas were used to provide a representative range of quality. The variation in the oils tested virtually covered the range of the chemical standard limits described by the International Olive Oil Council. A FOSS NIRSystems® 6500 spectrophotometer with a liquid cell holder was used. Multiple correlation coefficients squared (R2) for minor components stearic acid (0.86), and linolenic acid (0.85) were relatively low because the concentration range is very narrow compared with the reproducibility of the reference method. However, the major FA, oleic (0.99) and linoleic (1.00), FFA (0.97), and chlorophyll (0.98) provided high levels of accuracy. All of the parameters measured were sufficiently accurate for routine screening of olive oil.
Flavor stability and quality of high‐oleate and regular soybean oil blends during frying
Authors: Su Caiping , White Pamela 
Published: November 2006

AbstractThe percentages of oleate (18∶1), linoleate (18∶2), and linolenate (18∶3) in blended soybean oils (SBO) were evaluated for their impact on flavor stability and quality in fried foods. Six SBO treatments, including a control (conventional SBO, 21.5% 18∶1) and a high‐18∶1 SBO (HO, 79% 18∶1), were tested. In addition, these two oils were mixed in different ratios to make three blended oils containing 36.9, 50.7, and 64.7% 18∶1, abbreviated as 37%OA, 51%OA, and 65%OA, respectively. Also, a low‐18∶3 (LL) SBO containing 1.4% 18∶3 and 25.3% 18∶1 was tested. Bread cubes (8.19 cm3) were fried in each of 18 oils (6 treatments ×3 replicates). The fresh and stored bread cubes fried in 79%OA were second to the cubes fried in LL in overall flavor quality, were the weakest in intensity of stale, grassy, fishy, cardboard, and burnt flavors by sensory evaluation, and contained the least amounts of hexanal, hexanal, t‐2‐heptenal, t,t‐2,4‐nonadienal, and t,t‐2,4‐decadienal in volatile analysis. Other treatments were intermediate in these sensory and instrumental evaluations, as related to their 18∶1, 18∶2, and 18∶3 concentrations. In general, the results suggested that the overall flavor stability and eating quality of foods fried in the six oil treatments from the best to the poorest would be: LL≥79%OA, 65%OA, 51%OA, 37%OA, and control.
2S albumin gene expression in castor plant (Ricinus communis L.)
Authors: Chen Grace Q. , He Xiaohua , Liao Lucy P. , McKeon Thomas A. 
Published: November 2006

AbstractIn the castor plant (Ricinus communis L.), 2S albumins are highly allergenic seed proteins and are detrimental to the reintroduction of castor as a U.S. crop. Others have shown that the two 2S albumins are encoded by a single gene and processed from a precursor protein in castor. Little is known about the expression pattern of the 2S albumin gene. As part of a genetic approach to eliminating 2S albumin from castor, we investigated the developmental expression of this gene in castor seed. To assess seed developmental age quickly and accurately, we established a set of simple criteria, which included two visual markers, seed coat color and endosperm volume, and defined three phases that encompass the course of castor seed development. Northern analysis indicated that the 2S albumin mRNA is highly abundant in the mid‐phase of seed development. A comparison of 2S albumin genomic DNA and cDNA clones from two castor cultivars indicated that only a single gene is expressed. Protein domain sequence analysis revealed that castor 2S albumin contains the trypsin/α‐amylase inhibitor family domain, suggesting a role for the albumin in insect resistance.
Continuous fractionation of used frying oil by supercritical CO2
Authors: Osséo L. Sesti , Caputo G. , Gracia I. , Reverchon E. 
Published: November 2006

AbstractFractionation by supercritical carbon dioxide (SC−CO2) might be a way to purify used frying oils, since a selective separation of the oil components based on their polarity and M.W. can be attained. In this work, we studied the purification of peanut oil used for frying by SC−CO2 continuous fractionation in a packed column. The influence of pressure (15–35 MPa) and temperature (25–55°C) on the yield and on the composition of products was determined. The composition of the top and bottom products was evaluated by using size‐exclusion chromatography and other accepted chemical methods. Process conditions were selected to separate TG from degraded compounds. Experimental results indicated that the operating conditions leading to maximal TG recovery in the extract were 35 MPa, 55°C, and a solvent‐to‐feed ratio of 53. By operating at these conditions, it was possible to recover 97% of the TG placed on the column and about 52% by weight of the used frying oil. The composition of the purified top stream was very similar to that of fresh frying oil.
Enzymatic acidolysis of an arachidonic acid single‐cell oil with capric acid
Authors: Hamam Fayez , Shahidi Fereidoon 
Published: November 2006

AbstractIncorporation of capric acid (CA) into arachidonic acid (AA) single‐cell oil, using five commercial lipases, indicated that lipase PS‐30 from Pseudomonas sp. was most effective. The optimal conditions included an oil‐to‐CA mole ratio of 1∶3, a temperature of 45°C, incubation time of 24 h, 4% lipase from Pseudomonas sp., and a 2% (w/w) water content. Examination of positional distribution of FA on the glycerol backbone of modified AA single‐cell oil with CA showed that 89.7% of CA was concentrated in the sn‐1,3 positions of the TAG molecules. AA was mainly located at the sn‐2 position of the modified AA single‐cell oil. Enzymatically modified AA single‐cell oil had a higher conjugated dienes (CD) value than its unmodified counterpart. TBARS values of both modified and unmodified AA single‐cell oils increased progressively during the entire storage period, but no significant difference existed between TBARS values of both oils. Thus, enzymatically modified oil was more susceptible to oxidation than its unmodified counterpart, when considering both CD and TBARS values. Removal of natural antioxidants during oil modification might play a significant role in rapid oxidative deterioration of enzymatically modified oils. This possibility was confirmed when starting materials were subjected to the same reaction process in the absence of any enzyme, as the resultant oil was indeed significantly less stable than the control oil.