bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of elementary sulfur and sulfur compounds in lipid extracts by thin‐layer chromatography
Authors: Murphy Mary T. J. , Nagy Bartholomew , Rouser George , Kritchevsky Gene
Published: January 2007

Elementary sulfur, long chain thiols and sulfides in lipid mixtures can be separated and identified by thin layer chromatography (TLC), preparation of derivatives, development of typical flourescent colors with Rhodamine 6G under ultraviolet light, and colors with other spray reagents. Silica gel mixed with magnesium silicate and the same adsorbent plus silver nitrate are used for polar stationary phase and silver nitrate complexing chromatography, respectively.

Elementary sulfur yields a purple fluorescent spot with Rhodamine 6G in contrast to the yellow fluorescent of most lipids. Compounds isolated by means of TLC were further identified by spectroscopic methods. The sulfur bacterium (Chromatium sp.), and the Orgueil carbonaceous meteorite were analyzed by the new technique. Elementary sulfur was identified in both samples, but the lipid compositions of the bacteria and meteorite were found to be entirely different. The meteorite lipids and hydrocarbons were also different from the abiological hydrocarbons synthesized in a Miller high frequency spark discharge experiment.

The new analytical technique is suitable for the analysis of recent biological matter, petroleum, bitument and organic matter from marine sediments.
Determination of structure of unsaturated fatty acid positional isomers
Authors: Stein R. A.
Published: January 2007

The methods for determining the positions of unsaturation in fatty acids are reviewed. Overoxidation and isolation problems germane to permanganate oxidations, and the formation of by‐products and attack of solvents during ozonolysis are considered. The applicability of mass, nuclear magnetic and infrared spectral data to the problem of locating positions of unsaturation is discussed.
Determination of oxirane content of derivatives of fats
Authors: Maerker Gerhard
Published: January 2007

Although oxirane functions react readily with a large variety of chemical reagents, no single analytical method has been universally successful in measuring the oxirane content of all epoxides. This failure is ascribable to the manner in which the chemical reactivity of the three membered cyclic ethers is modified by molecular structure and by the presence of nearby substituents.

A survey of the various types of published analytical methods is given, but major emphasis is placed upon a discussion of procedures applicable to the analysis of epoxy derivatives of fats. Most of these latter methods depend upon the addition of some reagent, HX, to the epoxide ring with simultaneous cleavage of a carbon‐oxygen bond.
Integrated processing of peanut for the separation of major constituents
Authors: Subrahmanyan V. , Bhatia D. S. , Kalbag S. S. , Subramanian N.
Published: January 2007

Bench‐scale experiments were carried out on the processing of peanut by a new method. The decuticled kernels were pasted, and the paste was subjected to the Skipin process to recover approximately 30% oil; the residual paste was made into a dispersion at 10.0 pH and clarified to get a carbohydrate meal (15.7% moisture‐free); the clarified dispersion was centrifuged to obtain another 12% fat and the remaining dispersion was acidified to get the protein (21.9% moisture‐free).

Fifteen batches of 100‐1b. (45.4 kg.) each have been processed, and the reproducibility of the yields has been ascertained. The scope for increasing the oil yield and for improving protein quality is discussed.
Colorimetric determination of urease activity in soybean meals
Authors: Schramm Guenter , Aines Philip D.
Published: January 2007

A quantitative method for the determination of urease activity in soybean meals is described. The procedure is based on the incubation of the meal sample with a known amount of urea, followed by colorimetric determination of the urea with p‐dimethylaminobenz‐aldehyde after incubation. Urease activity is expressed as the amount of urea decomposed under the specified conditions. The test is both accurate and specific for urease. The method is very reproducible and sensitive, especially at low urease activities.
Gas‐Liquid chromatography of fatty derivatives. I. Separation of homologous series ofa‐olefins, n‐hydrocarbons, n‐nitriles, and n‐alcohols
Authors: Link W. E. , Hickman H. M. , Morrissette R. A.
Published: January 2007

Gas‐liquid chromatography has been shown to be applicable to the analysis of several fatty derivatives. The difficulties inherent in conventional separation schemes such as liquid‐liquid chromatography, fractional distillation, and crystallization can be overcome through the use of gas‐liquid chromatography. It becomes the preferred procedure for several reasons: a) fractions are more nearly pure, b) analysis time is a fraction of the time required for conventional separations, c) operational procedures are simple and highly reproducible, d) sample size requirements are low, e) the cost per unit analysis is low.

These factors suggest that gas‐liquid chromatography is highly useful as an analytical tool in fat research. In many cases the determination of chainlength distribution has already become a routine function.

There remain areas in which gas‐liquid chromatography has not been completely successful. Until very recently the separation of fatty methyl esters of similar chain length and varying degrees of unsaturation has been time‐consuming and tedious. Several new partitioning agents hold out great promise in the separation of the isomeric C18 fatty acids. More selective partitioning agents and refined techniques undoubtedly will equally improve the resolution of unsaturated alcohols and other unsaturated fatty derivatives.
Influence ofcis andtrans double bonds on the thermal and structural properties of monoacid triglycerides
Authors: Desmedt A. , Culot C. , Deroanne C. , Durant F. , Gibon V.
Published: January 2007

In order to determine the importance ofcis ortrans unsaturations from a technological point of view, the study of the structural and thermal properties of monoacid triglycerides: tristearin (SSS), triolein (OOO) and trielaidin (EEE) has been undertaken. X‐ray powder diffraction and differential scanning calorimetry are useful tools to elucidate the physicochemical properties of such compounds. In this work polymorphism, kinetics of polymorphism and intersolubility have been investigated. From a structural point of view, we have shown that, according to the polymorphic form, the conformational properties of EEE are similar to those of the corresponding saturated molecule SSS or to those of thecis unsaturated analogue OOO. The study of the intersolubility behavior of these three compounds has shown a different affinity of thecis andtrans unsaturated molecules vs the completely saturated one. By the same method, we have observed thattrans unsaturated hydrocarbon chains cocrystallize with bothcis‐unsaturated (OOO) and totally saturated hydrocarbon chains (SSS); thetrans double bond of EEE can adapt to the two kinds of lattices. The study of the kinetics of polymorphism has shown that 5% of OOO or EEE accelerate the β′→β transition of SSS, while the reason for the two phenomena is quite different. The adaptation of EEE tocis‐unsaturated and to saturated hydrocarbon chains shown in the structural and intersolubility behavior analyses also appears in the kinetic study, after adjunction of 5% of OOO into EEE. All the results confirm that, from structural and thermal points of view, EEE has an intermediate behavior between SSS and OOO.
Equilibrium distributions of key components of spearmint oil in sub/supercritical carbon dioxide
Authors: Platin Sevan , Özer Elif Ö. , Akman Ugur , Hortaçsu Öner
Published: January 2007

Effects of temperature (at 35, 45 or 55°C) and pressure (10–110 atm) on the relative distribution coefficients of the twelve key components of spearmint oil (essential oil ofMentha cardiaca; Scotch spearmint) at equilibrium in dense CO2 were investigated under conditions ranging from subcritical to supercritical regions. Effects of vapor pressure, molecular weight and polarity of the key components on their equilibrium distributions in sub/supercritical CO2 are discussed. At 35°C, all key components of spearmint oil are equally soluble in dense CO2 within the 12–102 atm pressure region. At 45 and 55°C, the key components are equally soluble for pressures greater than about 60 atm. However, around either 45°C/27 atm or 55°C/35 atm conditions, the relative distribution coefficients of all monoterpene hydrocarbons and of isomenthone (an oxygenated monoterpene) exhibit maxima, which are due to significantly higher vapor pressures of these components and significantly lower solvating power of the dense‐gas solvent at these particular temperatures and pressures. Vapor‐pressure effects, coupled with the decrease in solvating power, dominate the effects of polarity and molecular mass of the key components. Deterpenation of spearmint oil with dense CO2 is possible around either 45°C/27 atm or 55°C/35 atm, where the monoterpene hydrocarbons tend to concentrate in the CO2‐rich phase.
Benefits and limitations of a novel chlorophyll adsorbent
Authors: Chapman D. M.
Published: January 2007

Silica hydrogels acidified with strong mineral acids, such as sulfuric acid, are highly effective chlorophyll and phospholipid adsorbents relative to traditional acid‐activated bleaching earth (ABE), but they are not effective β‐carotene adsorbents. When an acidified silica is used as the only bleaching agent, sulfuric acid leaches into the oil, and after deodorization, Tintometer red and yellow (R/Y) numbers are higher than those for ABE‐bleached and deodorized oils. The fixed R/Y colors do not arise solely from the decomposition of β‐carotene during deodorization. Sequential treatments of canola oils with sulfuric acid/silica and ABE can be performed to overcome all of the drawbacks associated with sulfuric acid/silica treatment alone, such that finished oils can be produced by lower overall adsorbent dosages.
The formation of oxo‐ and hydroxy‐fatty acids in heated fats and oils
Authors: Schwartz Daniel P. , Rady Aly H. , Castañeda Soledad
Published: January 2007

A fast‐food fat (mostly tallow), olive oil and safflower oil were heated in air for 4 d and periodically analyzed for oxofatty acids (OFA), monohydroxy‐fatty acids (HFA) and polyhydroxy‐fatty acids (PHFA). After transmethylation, the OFA were estimated as 2,4‐dinitrophenylhydrazones, and the HFA and PHFA were quantitated as pyruvic acid 2,6‐dinitrophenylhydrazone esters. At least half of the maximum concentration attained for OFA, HFA and PHFA was generated between 16–24 h of heating of each oil. Safflower oil contained greater concentrations of HFA and PHFA than either olive oil or the fast‐food fat. The fastfood fat sample contained a greater concentration of OFA than did the other oils. The sum of the concentrations of OFA, HFA and PHFA at the time of maximum formation in the oils was approximately 260 μmoles/g at 48–72 h for safflower, 200 μmoles/g at 48–72 h for olive and 170 μmoles/g at 72 h for the fast‐food fat.
Triacylglycerol consumption during spore germination of vesicular‐arbuscular mycorrhizal fungi
Authors: Gaspar M. L. , Pollero R. J. , Cabello M. N.
Published: January 2007

Lipids and fatty acids of spores of the vesicular‐arbuscular mycorrhizal fungusGlomus versiforme were identified and quantitatively determined at different times of germination. Triacylglycerols were, by far, the most abundant lipid (38% on a wet‐weight basis). Phosphatidylethanolamine, together with minor quantities of other phospholipids, was the main polar lipid. Palmitoleic, palmitic and oleic acids were quantitatively the most important fatty acids in total lipids, and even more so in the triacylglycerol fraction. Minor percentages of fatty acids, identified as ω3 and ω6 polyunsaturated, completed the fatty acid spectra. Germination ofG. versiforme spores evokes a continuous decrease of triacylglycerols and an increase of phospholipids. The balance of fatty acids during germination suggests either a degradation or a transference of fatty acids from triacylglycerols to phospholipids.
Selectivity control in substituted fatty amines synthesis from esters or nitriles in the presence of bifunctional catalysts
Authors: Barrault J. , Brunet S. , Suppo‐Essayem N. , Piccirilli A. , Guimon C.
Published: January 2007

Copper chromite‐type catalysts, supported by alumina or graphite and promoted with barium, were used for the onestep synthesis of tertiary fatty amines [R2NCH3 or RN(CH3)2] from ester, acid or nitrile and ammonia, methanol and hydrogen. The surface composition of the catalysts, studied by X‐ray photoelectron spectroscopy and by adsorption experiments, showed that there was a correlation between selectivity and the presence of a well‐dispersed CuCrO2 phase, stabilized with barium. Moreover, the elements influencing the stability of the copper catalysts were also studied, and the promoter or/and the support increased the copper surface area and the stability of the catalyst in the presence of water or ammonia.
Influence of fatty acids on the tocopherol stability in vegetable oils during microwave heating
Authors: Yoshida Hiromi , Tatsumi Mikiko , Kajimoto Goro
Published: January 2007

Effects of 0, 0.05, 0.25, 0.50 and 1.0% levels of fatty acids (caproic, caprylic, capric and lauric) or hydrocarbons (decane and dodecane) on tocopherol stability in vegetable oils during microwave heating were determined by measuring tocopherol losses and carbonyl and anisidine values. The fatty acids showed similar prooxidant activities toward tocopherols in purified vegetable, oils when heated in a microwave oven. However, decane or dodecane, which had the same number of carbons as capric or lauric acid but no carboxylic group, did not show prooxidant activity. The shorter the chainlength and the higher the level of fatty acids, the greater was the reduction of tocopherols in the oils. The addition of low‐molecular weight fatty acids resulted in greater acceleration in the oxidation of to pay attention to these free fatty acids produced in the oils when heated in a microwave oven.
Positional analysis and determination of triacylglycerol structure ofArgania spinosa seed oil
Authors: Maurin R. , Fellat‐Zarrouck K. , Ksir M.
Published: January 2007

The distribution of fatty acids between the sn‐1, sn‐2 and sn‐3 positions of triacylglycerols fromArgania spinosa seed oil of Morocco has been determined. Saturated fatty acids showed a preference for external positions. The sn‐1 position contained slightly more palmitic acid than the sn‐3 position, whereas stearic acid was preferentially esterified at the sn‐3 position. Linoleic acid occurred predominantly in the sn‐2 position with lesser amount evenly distributed between the sn‐1 and the sn‐3 positions, as generally found in vegetable oils. Oleic acid was distributed with a slight preference shown for the internal position, whereas the distribution between the external positions revealed a slight preference for the sn‐1 position. The distribution of the triacylglycerols determined from high‐performance liquid chromatography (HPLC) is at variance with that calculated from the 1‐random 2‐random 3‐random distribution theory. This is particularly true for trioleoyl and trilinoleoylglycerols. In contrast, the agreement between theory and experiment is good for triacylglycerols containing two oleoyl and one linoleoyl chains, one oleoyl, one linoleoyl and one palmitoyl chains or one oleoyl, one palmitoyl, and one stearoyl chains.
Continuous transmethylation of palm oil in an organic solvent
Authors: Krisnangkura Kanit , Simamaharnnop Ratchadaporn
Published: January 2007

Palm oil was transmethylated continuously at 70°C in an organic solvent with sodium methoxide as a catalyst. The optimum ratio of toluene to palm oil is 1∶1 (v/v). When the methanol‐to‐oil molar ratio was 13∶1, transmethylation was 96% complete within 60 seconds. At higher molar ratio (17∶1), transmethylation was 99% complete in 15 seconds. For lower molar ratios of methanol‐to‐oil (9∶1 and 5.8∶1), yields of palm oil methyl ester (POME) were 84 and 58%, respectively. Benzene was also a good solvent for transmethylation, but the yield of POME was slightly lower than toluene. Tetrahydrofuran did not accelerate transmethylation.
Technological and economical aspects of the metathesis of unsaturated esters
Authors: Sibeijn M. , Poels E. K. , Bliek A. , Moulijn J. A.
Published: January 2007

The metathesis of alkenes is a well‐established reaction that is applied in various commercial processes. The meta‐thesis of functionalized olefins has not yet been commercialized despite its considerable potential. The conversion of oleochemical feedstocks into specialty chemicals appears especially attractive. In this paper, a process scheme is proposed for the production of 1,18‐dimethyl octadecanedioate from pure methyl oleate by metathesis. The chemical and technological bottlenecks are explored, and a rough economic evaluation of this route is given. From these considerations, it is concluded that such a process for the metathesis of functionalized alkenes could be viable only if certain conditions are met. Rapid catalyst deactivation is identified as one of the main obstacles. Feedstock purity, efficient recycling of unreacted feed and multiple catalyst regeneration are crucial for economic feasibility. Rhenium‐based catalysts are to be preferred over molybdenum ones because their activation is easier and regenerability is superior. Finally, the direction for future technological and catalysis research is given based upon the results of this work.
Effects of the degree of unsaturation of coexisting triacylglycerols on cholesterol oxidation
Authors: Li Nan , Ohshima Toshiaki , Shozen Kei‐ichi , Ushio Hideki , Koizumi Chiaki
Published: January 2007

In order to evaluate the effects of the degree of unsaturation of triacylglycerols on cholesterol oxidation, mixtures of purified sardine oil triacylglycerols (iodine value, IV=182.6) and cholesterol; of partially hydrogenated sardine oil triacylglycerols (IV=174.5) and cholesterol; and of fully hydrogenated sardine oil triacylglycerols (IV=92.0) and cholesterol were incubated at 25°C in the dark. The oxidative stability of the samples decreased with increasing degree of unsaturation of the triacylglycerols in the sample mixtures; the induction period for peroxide values (PV) of the sardine oil triacylglycerols and cholesterol was shorter than that of the partially hydrogenated sardine oil triacylglycerols and cholesterol. Certain polyunsaturated fatty acids (PUFAs) in the constituent fatty acids of sardine oil triacylglycerols started to decrease after a shorter induction period compared with that of the partially hydrogenated triacylglycerols. The prominent cholesterol oxides accumulated in the samples were 7β‐hydroxycholesterol, 7‐ketocholesterol, β‐epoxide and cholestane triol. The tendency for accumulation of cholesterol oxides in the time course coincided with the changes in PV as well as the decrease in PUFAs. Cholesterol was oxidized in conjunction with autoxidation of coexisting fish oil triacylglycerols. Although lowering the degree of unsaturation of fish oil triacylglycerols was effective in prolonging the induction period of cholesterol oxidation, the rate of cholesterol oxidation in the cholesterol oxides' formation phase after the induction period was not affected by the difference in the proportion of highly unsaturated fatty acids in the natural and partially hydrogenated triacylglycerols of fish oils.
Pilot‐plant selective hydrogenation of soybean oil: Activation and evaluation of copper‐containing catalysts
Authors: Moulton K. J. , Moore D. J. , Beal R. E.
Published: January 2007

In pilot‐plant tests, the linolenate content of soybean oil was reduced to less than 1% without increasing the saturates, by hydrogenation to an IV of about 115 with an active copper‐chromite catalyst. The linolenate‐linoleate selectivity ratio (KLe/KLo) was from 9 to 12. Several commercial copper‐chromite catalysts were used in hydrogenation tests. The activities of four of five commercial catalysts tested were improved to various degrees by heating in air at 350 C (one was inactive both before and after heating). Examination by differential thermal analysis (DTA) of each catalyst, just as received and then after being heated at 350 C, demonstrated that heating greatly diminished or removed peak areas from the DTA curve. Studies made with one commerical copper‐chromium‐barium catalyst showed that heating the catalyst was also necessary to gain maximum linolenate‐linoleate selectivity in hydrogenating soybean oil.
Relationship of structure to properties of surfactants. 15 Isomeric sulfated polyoxyethylenated Guerbet alcohols
Authors: Murphy D. S. , Zhu Z. H. , Yuan X. Y. , Rosen M. J.
Published: January 2007

The properties at 25°C in aqueous 0.1M NaCl at the aqueous solution/air, aqueous solution/hexadecane, and aqueous solution/hydrophobic solid interfaces of two isomeric Guerbet alcohol‐derived surfactants C8H17CH(C6H13)CH2(OC2H4)5SO4Na, one in which the octyl and hexyl groups are both linear (L isomer), the other in which they are both highly branched (B isomer), have been investigated and compared in some cases with commercial sodium linear dodecylbenzene‐sulfonate (LAS). The cmc value increases, the pC20 value decreases, and the ΔGoad value becomes less negative in the order: L isomer—B isomer—LAS. The minimum area/molecule at the aqueous solution/air interface increases in the order: LAS≪L isomer<B isomer.

The L isomer is slightly more hydrophobic than the B isomer, and both are considerably more surface‐active than LAS. The greater steric inhibition to micellization in the B isomer results in the lowest minimum surface tension. Both isomers have similar minimum interfacial tension values against hexadecane. Unusually small minimum area/molecule values for the two isomers at the aqueous solution/hydrophobic solid interface may indicate multilayer adsorption there. Both isomers are more efficient at reducing the contact angle than LAS. Mixtures of the B isomer with the corresponding unsulfated Guerbet alcohol show only weak interaction between the two. No synergism in surface (or interfacial) tension reduction efficiency or micelle formation exists at either the aqueous solution/air or aqueous solution interface but the mixture does show synergism in surface (or interfacial) tension reduction effectiveness, yielding a surface tension value of 28.2 dynes/cm, and an interfacial tension value of 0.1 dyne/cm against hexadecane. Draves wetting times increase in the order: B isomer<LASL isomer.
Influence of interesterification on the oxidative stability of marine oil triacylglycerols
Authors: Kimoto Hiromi , Endo Yasushi , Fujimoto Kenshiro
Published: January 2007

To understand the relationship between triacylglycerol structure of marine oils and their oxidative stability, peroxide values and absorbed oxygen levels of whale, sardine, cod liver and skipjack oils, interesterified by lipase and NaOCH3, were compared with those of native oils during storage at 40°C. Triacylglycerol structures of marine oils were characterized by high‐performance liquid chromatography and differential scanning calorimetry analyses. Enzymatically interesterified fish oils were more stable than native oils because the level of highly unsaturated triacylglycerols was decreased. However, the oxidative stability of interesterified whale oil was more susceptible to oxidation than the native oil.
Enzymatic phosphatidylcholine hydrolysis in organic solvents: An examination of selected commercially available lipases
Authors: Haas M. J. , Scott K. , Jun W. , Janssen G.
Published: January 2007

Eight commercial lipase preparations were examined for the ability to hydrolyze phosphatidylcholine (PC) in hexane solutions. Only the enzymes fromHumicola lanuginosa, Rhizopus delemar andCandida rugosa displayed appreciable activity. Solvent polarity was the largest single factor affecting activity. TheH. lanuginosa sample was most active in polar solvents. TheR. delemar preparation was most active in polar (2‐hexamone) and nonpolar (decane) solvents and least active in solvents of intermediate polarity (hexane). The solvent dependence of the activity of theC. rugosa enzyme varied with the ratio of substrate to enzyme. Different degrees of activity were retained by the three enzymes after passive immobilization on Celite, controlled‐pore glass, polypropylene and Amberlite XAD‐7 resins. No single resin yielded the best retained activity for all three preparations. When examined in 2‐octanone, hexane and isooctane, the Celite‐immobilizedR. delemar andH. lanuginosa enzymes exhibited highest activity in 2‐octanone, while immobilizedC. rugosa was most active in isooctane. The water content at which maximum activity was observed was relatively independent of solvent polarity and the amount of catalyst but was proportional to the amount of PC in the reaction. The retention of activity by immobilizedRhizomucor miehei lipase (Lipozyme) during multiple hydrolytic cycles required a reduction in the water content of the system below that yielding optimal activity in a single cycle.
Kinetics of catalytic transfer hydrogenation of soybean oil
Authors: Smidovnik A. , Kobe J. , Leskovsek S. , Koloini T.
Published: January 2007

The catalytic transfer hydrogenation of soybean oil was studied by using various concentrations of sodium formate solutions, an emulsifier and paladium on a carbon catalyst. Sodium formate concentration and addition of the emuldifier significantly affect the reaction rate because of their influence on the liquid/liquid interface. Under conditions in which diffusion effects are eliminated, all reactions carried out in diluted sodium formate solution obey first‐order kinetics with respect to fatty acids. This allows control over the hydrogenation process of soybean oil, needed to obtain partially hydrogenated oil containing about 1% linolenic acid and a relatively high level of linoleic acid with no increase in the stearic acid concentration.
Oil and minor components of sesame (Sesamum indicum L.) strains
Authors: Tashiro T. , Fukuda Y. , Osawa T. , Namiki M.
Published: January 2007

Oil and mior components of sesamin and sesamolin were studied in 42 strains ofSesamum indicum L. The oil contents of the seed ranged from 43.4 to 58.8% and varied inversely with the percentage of hull (r=−0.804, significant at the 1% level). The hull percentage was used as a criterion to predict oil content. The percentage of sesamin in the oil ranged from 0.07 to 0.61% and that of sesamolin from 0.02 to 0.48%. There was a significant positive correlation between the oil content of the seed and the sesamin content of the oil (r=0.608, significant at the 1% level); no correlation was found between the oil and sesamolin contents.

The average oil content found for the white‐seeded strains was 55.0% and for the black‐seeded strains 47.8%, the difference of 7.2% being significant at the 1% level. The white‐ and black‐seed strains also differed significantly in sesamin content, but not in sesamolin content.
Oxidative stability of soybean oil at different stages of refining
Authors: Kwon T. W. , Snyder H. E. , Brown H. G.
Published: January 2007

Oxidative stabilities of soybean oil samples at 7 different stages of commercial refinement were measured by weight increases. Also, a method was developed for isolating essentially pure soybean triglyceride, and its oxidative stability was measured. Crude oil was most stable and the highly purified soybean triglyceride was least stable, with other samples being intermediate in stability. Adding phospholipids and tocopherols to the highly purified soybean triglyceride gave its oxidative stability, and in combination they were synergistic in delaying oxidation. The weight increase method demonstrated that surface exposure is an important variable in rates of autoxidation.
Sensory characteristics and oxidative stability of soybean oil and flour extracted with aqueous isopropyl alcohol
Authors: Warner K. , Baker E. C.
Published: January 2007

Soybean flakes extracted with hexane or aqueous isopropyl alcohol (85%, 87.7% and 90.5% IPA by weight) were processed to toasted flours and the miscellas to refined soybean oils. These products were evaluated for sensory characteristics and oxidative stability. Sensory analyses of initial oils and flours indicated good quality products. Initial flavor scores of IPA‐extracted oils and flours were not significantly different from those of hexane‐extracted oil and flour. Flour samples aged at 49 C for 1 mo and 37 C for 3 mo were rated slightly lower in flavor score than the initial flours. Flavor scores of oils decreased after aging but remained acceptable. Oils extracted with aqueous IPA concentrations of 85% and 90.5% received significantly lower scores than oils extracted with hexane or 87.7% IPA after 8 hr of fluorescent light exposure. Oxidative stability measured by the induction of weight increases of the oils during aging was similar. Residual solvent flavors were slightly detectable in unaged IPA flours and in those aged 3 mo at 37 C.
Use of a gas chromatographic reactor to study lipid photooxidation
Authors: Faria J. A. F. , Mukai M. K.
Published: January 2007

A gas chromatographic reactor can be used to investigate the prooxidant activities of different light sources on polyunsaturated lipids, including linoleic acid and safflower oil. The rate of oxidation was followed from the early stages of oxygen uptake, using a thermal conductivity detector (TCD). The experiments were made at low O2 concentrations and at a broad range of temperatures. To monitor the effect of light on the oxidation of linoleic acid, chlorophyll and methylene blue were used as sensitizers, and β‐carotene was used as a reported inhibitor of oxidation. The simultaneous measurements of oxygen uptake and volatiles formation were also monitored using a TCD and flame ionization detector (FID). The method is presently being developed as a technique to predict the stability of fatty foods packaged in transparent or translucent materials.
Solid phases of trimargarin: A comparison to tristearin
Authors: Simpson T. D.
Published: January 2007

Data from Raman spectroscopy, X‐ray diffraction, infrared spectroscopy and differential scanning calorimetry confirm the existence of four solid state phases for trimargarin. Results of the trimargarin investigation are compared to previous results of tristearin and examined in the light of odd vs even chain‐length triglycerides. The conclusion reached is that polymorphic properties of triglycerides result from a balance of three dominant interactions: end‐group planar interactions, lateral hydrocarbon chain interactions and glycerol units intermolecular interactions. This contrasts to a general belief that the end‐group planar interactions dictate physical behavior of lipids.
Polycarboxylic acids containing acetal functions: calcium sequestering compounds based on oxidized carbohydrates
Authors: Nieuwenhuizen M. S. , Kieboom A. P. G. , van Bekkum H.
Published: January 2007

A number of polycarboxylic acids containing acetal functions have been prepared by a two‐step oxidation of carbohydrates. Their calcium sequestering behavior is compared with that of a series of model polycarboxylic acids. It is found that calcium sequestration by oxidized carbohydrates is less than that by corresponding ether polycarboxylates, since (a) acetal oxygens have a lower coordinating power than ether oxygens, and (b) there is extra steric repulsion upon calcium complexation by both the additional CH2 OH groups and the unfavorable natural configuration of the oxidized carbohydrates investigated. Some of the oxidized carbohydrates show greater calcium sequestering capacities than corresponds to the stability constant. This is probably caused by crystal growth inhibition or precipitation‐inhibition phenomena. Two model compounds illustrate that the acetal moiety is sufficiently stable under washing conditions, whilst it hydrolyses under acidic waste water conditions into small (hydr)oxycarboxylates.
Separation and quantitative determination of monoacylglycerol mixtures by reversed phase HPLC
Authors: Maruyama Kazushige , Yonese Chizuo
Published: January 2007

The separation and quantitative determination of underivatized saturated and unsaturated monoacylglycerol were examined by reversed phase high performance liquid chromatography using acetonitrile/water as the mobile phase. Monoacylglycerol (MG) mixtures containing saturated MG (C6‐MG‐C18‐MG), monooleoylglycerol and monolinoleoylglycerol were sufficiently resolved, but mixtures of 1‐MG and 2‐MG with the same acyl group could not be separated under the conditions given below: column, C‐8 chemical bonded column (4.6 × 250 mm); sample solvent, diethyl ether (UV detector at 210–215 nm) or chloroform; mobile phase, acetonitrile/water (7:3, v/v). Quantitative determinations were made for mixtures of three components (representative standard MGs) on a reversed phase column (Unisil Q, C‐8) using a UV detector and the internal standard method. Standard deviation and coefficient of variation gave accurate, reproducible results.
Computer modeling of packing arrangements and transitions in saturated‐cis‐unsaturated mixed triglycerides
Authors: Hagemann J. W. , Rothfus J. A.
Published: January 2007

Conformational analysis of modeledcis‐unsaturated chains in triunsaturated and symmetrical monounsaturated triglycerides has identified pseudo‐linear chain orientations that allow lower molecular mechanical energies than are possible with conventionalcis‐chains. Energy plots recorded during bond rotations near the double bond show that energy barriers between linear and normalcis‐configurations are often less than 5 Kcal/mol. Pseudo‐linear orientations, which allow compatible side‐by‐side packing of saturated and unsaturated chains in double‐chainlength mixed triglycerides, also provide a route for efficient transformation between double‐chainlength and triple‐chainlength configurations in solid polymorphic triglycerides.
Inhibition of mitochondrial fatty acid elongation by antibodies to 3‐ketoacyl‐CoA thiolase
Authors: Staack Harold , Davidson Bruce , Schulz Horst
Published: January 2007

Antibodies to pig heart 3‐ketoacyl‐CoA thiolase inhibited almost completely and in a parallel fashion thiolase and the acetyl‐CoA‐dependent fatty acid elongation system present in an acetone powder extract of pig heart mitochondria. This finding leads to the conclusion that mitochondrial fatty acid elongation occurs by reversal of fatty acid oxidation. Several lines of evidence point to the thiolase‐catalyzed condensation reaction as the rate‐limiting step in the formation of elongated products. However, the accumulation of hydroxy acids suggests the enoyl‐CoA reductase activity is limiting in the synthesis of saturated fatty acids.
Pyrrolidone‐based surfactants (a literature review)
Authors: Login Robert B.
Published: January 2007

As the alkyl group of N‐alkylated pyrrolidones is increased to C8P, surface‐active properties become important. The resulting surfactant can interact synergistically with an anionic surfactant. This interaction is based on the electronegativity of the pyrrolidone carbonyl oxygen which can accept a proton to form a pseudoquaternary ammonium ion that can form an ion pair with large anions (i.e., anionic surfactants). The resulting ion pair is further stabilized by hydrophobic bonding between the two alkyl chains. In addition, pyrrolidone can electrostatically interact with aromatics, hydrogen‐bond to nonionics, and, in essence, associate electrostatically/hydrophobically similarly to polyvinylpyrrolidone. This interaction of the pyrrolidone functional group can be transposed from one surfactant hydrophobe structure to another. This paper reviews the literature concerning the addition of pyrrolidone to a variety of hydrophobes of interest to both industrial and academic researchers. The chemistry of selected surface‐active pyrrolidone derivatives, prepared from butyrolactone, aminoethylpyrrolidone, epoxypropylpyrrolidone, chloromethylpyrrolidone and itaconic acid, is reviewed. Pyrrolidone is a versatile substituent, capable of enhancing the performance of a variety of surfactant structures by improving water solubility, compatibility and solvency in a compact head group that favors surfactancy. In addition, the pyrrolidone ring, when incorporated into derivatives, usually reduces toxicity.
Coffee stain on textiles. Mechanisms of staining and stain removal
Authors: Kissa Erik
Published: January 2007

Coffee stains on textiles are mainly caused by the water‐soluble and acidic colored substances in coffee. The acidic nature of coffee stain has been shown by ultraviolet and visible spectroscopy of coffee as a function of pH; ion‐pair formation with a cationic surfactant and titration with Hyamine 1622 and a surfactant‐specific electrode; and precipitation of the colored components in coffee with barium hydroxide as a barium salt. The permanence of coffee stains on textiles depends on the nature of the fibers. The affinity of coffee stain to fibers, indicated by resistance to detergency, increases in the order polyester<cotton<nylon. Coffee stain has little affinity to polyester fibers but adheres to cotton and even more firmly to nylon. The strong affinity to nylon and the pH dependence of staining suggest an ionic interaction of carboxyl and phenolic groups with amine end‐groups in nylon. The ionic attraction is augmented by nonionic interactions that are enhanced by the oligomeric or polymeric nature of the staining substances. In accord with the dominantly acidic character of coffee stain, an alkaline medium is needed for the dislodgment of coffee stain from nylon fibers. Bleaching of coffee in solution with perborate, activated with sodiumn‐nonanoyloxybenzenesulfonate, or Oxone® (DuPont, Wilmington, DE) obeys pseudo first‐order kinetics. Oxone, a peroxysulfate triple salt, is a more powerful oxidant for coffee stain than sodium perborate, but its use is limited by the bleach fastness of dyes.
The effect of relative humidity gradient on water vapor permeance of lipid and lipid‐hydrocolloid bilayer films
Authors: Greener Donhowe I. , Fennema O.
Published: January 2007

The water vapor (WV) permeance of lipid and lipid‐hydrocolloid films exposed to relative humidity (RH) gradients of 100–0%, 100–50%, 100–65% and 100–80% RH were determined. The lipids used were beeswax (BW) or a blend of BW and acetylated monoglycerides (AG). Hydrocolloids used were methylcellulose, carboxymethylcellulose or ethylcellulose (EC). All films, except those containing EC, exhibited increased water vapor permeance as the RH gradient was reduced by raising the low‐end RH. This increase in permeance was apparently caused by hydration and swelling across the entire film thickness, thus facilitating water movement through the film. Because of its hydrophobicity, EC likely lessened this swelling. Knowledge of the WV properties of edible films at relatively small gradients in the upper half of the RH spectrum, such as those used in this study, is useful because these conditions are far more common to foods than are the 100–0% gradients that are often used when evaluating films. Even though the WV permeance of BW and BW/AG films increased greatly at the 100–80% RH gradient, as compared to gradients ranging from 100–65% to 100–0%, they still possess WV barrier properties sufficient to be useful for foods.
Synthesis of oleyl oleate as a jojoba oil analog
Authors: Sánchez N. , Martinez M. , Aracil J. , Corma A.
Published: January 2007

Synthesis of a wax ester analog of jojoba oil was accomplished from oleic acid and oleyl alcohol with a zeolite as catalyst. A full 23 factorial design at two levels has been used in the synthesis. The variables selected were temperature, reduced pressure and initial catalyst concentration. The most important variable within the range studied was temperature. Reduced pressure had a negative influence, and initial catalyst concentration showed a positive influence on the process. A response equation has been determined for the yield of ester. The properties of the synthesized product are similar to those of natural jojoba oil.
Lipase‐catalyzed transesterification of phosphatidylcholine at controlled water activity
Authors: Svensson Ingemar , Adlercreutz Patrick , Mattiasson Bo
Published: January 2007

The incorporation of a free fatty acid into thesn‐1 position of phosphatidylcholine by lipase‐catalyzed transesterification was investigated. The thermodynamic water activity of both the enzyme preparation and the substrate solution was adjusted to the same value prior to the reaction. The reaction rate increased with increasing water activity but the yield of modified phosphatidylcholine decreased due to hydrolysis. By using a large excess of the free fatty acid (heptadecanoic acid), the hydrolysis reaction was slowed down, so a higher yield was obtained at a given degree of incorporation. The best results were obtained withRhizopus arrhizus lipase immobilized by adsorption on a polypropylene support. With this preparation, a yield of 60% and nearly 50% incorporation of heptadecanoic acid (100% incorporation in thesn‐1 position) was obtained at a water activity of 0.064. The enzyme preparation had good operational stability and position specificity. Little incorporation (<1%) was observed in thesn‐2 position, when almost all the fatty acid in thesn‐1 position was exchanged.
Effects of deodorization and steam‐refining parameters on finished oil quality
Authors: Maza A. , Ormsbee R. A. , Strecker L. R.
Published: January 2007

Deodorization and steam‐refining parameters have significant impact on the quality of finished oil. Hence, optimization of parameters is critical for the production of acceptable oil. Temperature, time, throughput rate, sparging steam rate and pressure must be optimized to produce edible oil with desirable characteristics. Process optimization modeling in the laboratory, pilot plant and refinery is utilized to obtain predictive equations correlating product characteristics with deodorization parameters and feedstock properties. This optimization technique is demonstrated on model feedstocks and typical commercial oil. Finished corn and soybean oil quality are expressed by tocopherols and free fatty acid levels and sensory attributes during accelerated storage.
Quality factors in exported peanuts from agrentina, China and the united states
Authors: Sanders T. H. , Vercellotti J. R. , Crippen K. L. , Hinsch R. T. , Rasmussen G. K. , Edwards J. H.
Published: January 2007

In three crop years (1986–1988), peanuts exported from Argentina, China and the United States were evaluated for biochemical composition relative to flavor and shelf‐life quality potentials and physical size conformity. Relationships were consistent in that oil stability was associated with high tocopherol and oleic/linoleic acid ratio, and with low free fatty acid, peroxide, carbonyl, and copper and iron content. Peanuts from specific origins had recurring component patterns, with highest indications for shelf life and flavor potential in United States samples. Although no single factor or group of factors can be relied on completely as predictors of flavor or quality, these data establish a significant positive relationship between oil quality factors and roasted peanut flavor quality potential. Argentina and United States peanuts were the most consistently sized, and China peanuts generally had the lowest count/weight.
Detection of interesterified fats in hydrogenated fats
Authors: Adhikari S. , Adhikari J.
Published: January 2007

Interesterification of fats is being used increasingly as an alternative to hydrogenation in preparing shortening and margarine bases. The detection of interesterified fats in vanaspati (a hydrogenated fat) is relevant because of possible adulteration problems. Either palmitic acid‐rich or stearic acid‐rich interesterified fats were blended with 13 market samples of hydrogenated fat (vanaspati) and examined by on‐plate lipase hydrolysis of glycerides, gas chromatographic determination of fatty acids of the isolated 2‐monoglycerides and calculation of two emperical indices. These were R1, the ratio of the amounts of palmitic acid present in the 2‐position to that in the total glyceride, and R2, the ratio of saturated acid present in the 2‐position to total saturated fatty acid in the fat. The vanaspati, R1 was always below 10 and R2 was always below 20. The presence of 5–10% interesterified fat raised both figures and offered a suitable basis for the detection of interesterified fats in hydrogenated fats.
Composition of crystals of palm olein formed at room temperature
Authors: Swe P. Z. , Man Y. B. Che , Ghazali H. M.
Published: January 2007

The composition of purified plam olein crystals formed at room temperature (25°C) was identified in this study. Two peaks were obtained when the crystals were analyzed by reverse‐phase high‐performance liquid chromatography (RP‐HPLC). The retention times of these peaks suggested that they were not triglycerides. Gas‐liquid chromatography of fatty acid methyl ester analysis of the crystals showed the presence of C16, C18:0, and C18:1 fatty acids. Further analysis by gas‐liquid chromatography of carbon number, after collecting the fractions from RP‐HPLC, concluded that the major peak A was 1,3‐dipalmito‐glycerol. The minor peak B was tentatively identified as 1‐palmito‐3‐stearo‐glycerol and/or 1‐palmito‐3‐oleo‐glycerol due to unavailability of respective standard glycerides. The differential scanning calorimetry thermogram of the crystals show that A and B were indeed the high melting glycerides, with melting and crystallization points of 70.4 and 53.8°C, respectively.
The mechanism of cobalt drier action
Authors: Girard Theodore A. , Beispiel Myron , Bricker Clark E.
Published: January 2007

The influence of cobalt driers on the initial stages of the drying of polyunsaturated esters has been studied. Cobalt (II) appears to from an unstable complex of variable composition with the polyunsaturated ester. This complex catalyzes the uptake of oxygen and increases the rate of oxygen absorption by the ester. The energy of activation for oxygen uptake by the ester in the presence of cobalt is only 1.3 kcal/mole, while in the absence of cobalt, the activation energy is 10.8 kcal/mole. The absorption of oxygen by the ester is followed by the formation of hydroxy and/or hydroperoxy groups, the loss of alkene groups, an increase in conjugation and conversion from the cis to the trans isomer. Polymerization occurs during these latter changes.
Preparation of 2‐decyl‐2‐hydroxymethyl‐1, 3‐propanediol from dodecanal and from petroselinic acid
Authors: Holmes R. L. , Moreau J. P.
Published: January 2007

Dodecanal was reacted with formaldehyde and potassium hydroxide in ethanol and with formaldehyde and calcium oxide in aqueous methanol to give about 30% of the theoretical yield of 2‐decyl‐2‐hydroxymethyl‐1, 3‐propanediol (DHP).

Petroselinic acid was ozonized in methylene chloride, and the ozonide reduced to aldehydes with formic acid and zine. The methylene chloride solution was emulsified with water and reacted with formaldehyde and potassium hydroxide. A yield of 32% of DHP was isolated.

Pure 5,5,5‐trimethylol valeric acid could not be isolated from the reaction mixture of formaldehyde and potassium hydroxide with the mixed aldehydes from petroselinic acid, but a small amount of material was isolated by ion exchange resins which had high infrared absorption for hydroxyl and carboxylic acid and which polymerized on standing.