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Showing papers in "Journal of the American Oil Chemists' Society in 1988"


Journal ArticleDOI
TL;DR: A 17-hydroxyocta-decanoic acid at the C-1’ -position and acetate groups at the B-6’ and C-6' -positions of sophorose were found as substituents in the lactone and acidic forms of these lipids.
Abstract: Cultivation of Torulopsis bombicola ATCC 22214 on a mixture of glucose and oleic acid (A) or oleic acid alone (B) produced large amounts of sophorose lipids. In the case of A, 38 g/1 of crude product were finally isolated; fermentation B led to 77 g/1. After separation by MPLC and TLC, six glycolipids were obtained and identified by NMR and fast atom bombardment-mass spectrometry (FAB-MS). In general, a 17-hydroxyocta-decanoic acid at the C-1’ -position and acetate groups at the C-6’ -and C-6’ -positions of sophorose were found as substituents in the lactone and acidic forms of these lipids. The composition of product from A was as follows: 62% of sophorolipid 1’,4’ -lactone 6’ ,6’ -diacetate (SL-1), 4% of sophorolipid 1’,4’-lactone 6’-monoacetate (SL-2), 4% of sophorolipid 1’,4 ’-lactone (SL-3), 4% of sophorolipid 1’,6’-and l’,6’-lactones (SL-4a,b), 4% of sophorolipid 6’-monoacetate acid (SL-5), 4% of sophorolipid acid (SL-6) and finally 17% of other lipids. In B, the principal lactone (40%) had a double bond in the fatty acid moiety; the other components were identical with the above products. Yields of 13% SL-2 and of 35% lipids containing no carbohydrate were significant. SL-1 was deacetylated to SL-3 (yield: 25-307c) using acetyl-esterase in a two-phase system (cyclohexane/water).

290 citations


Journal ArticleDOI
TL;DR: In this article, thermally decomposed soybean oil was distilled in air or in nitrogen sparge with standard ASTM distillation apparatus, and the results showed that approximately 75% of the products were made up of alkanes, alkenes, aromatics and carboxylic acids with carbon numbers ranging from 4 to more than 20.
Abstract: Soybean oil was thermally decomposed and distilled in air or in nitrogen sparge with standard ASTM distillation apparatus. GC-MS analysis showed that approximately 75% of the products were made up of alkanes, alkenes, aromatics and carboxylic acids with carbon numbers ranging from 4 to more than 20. Fuel properties of the pyrolyzed materials were characterized and compared with those of the parent oil. The pyrolyzates had lower viscosities and higher cetane numbers than the parent vegetable oil. Thermally decomposed soybean oil shows promise as alternative fuel for the direct-injection diesel engine.

268 citations


Journal ArticleDOI
TL;DR: In this paper, the preparation of methyl esters of used frying oil, available as waste from restaurants and households, is described, and fuel specifications of this fuel are given, and values for gaseous (HC, CO, NOx) and particulate emissions, measured with a vehicle powered by a turbocharged, direct injection diesel engine, are shown.
Abstract: The preparation of methyl esters of used frying oil, available as waste from restaurants and households, is described. Fuel specifications of this fuel are given, and values for gaseous (HC, CO, NOx) and particulate emissions, measured with a vehicle powered by a turbocharged, direct injection diesel engine, are shown. The ester fuel shows slightly lower HC and CO emissions but increased NOx values compared with reference US-2D fuel. The particulate emissions, however, are significantly lower with used frying oil. Preliminary results of an engine road test are described.

211 citations


Journal ArticleDOI
TL;DR: In this paper, a preliminary heat-bleach at 250 C was used for the determination of total tocopherols in crude as well as refined palm oil, olein and stearin.
Abstract: By using a preliminary heat-bleach at 250 C the Emmerie-Engel method has been adapted for the determination of total tocopherols (including tocotrienols) in crude as well as refined palm oil, olein and stearin. Total tocopherol contents found were: Crude palm oil, 794 ppm (n=10); RBD palm oil, 563 ppm (n=13); RBD palm olein, 643 ppm (n=40); RBD palm stearin, 261 ppm (n=19), where n is the number of samples analyzed. During the detergent fractionation no tocopherols were lost, but the tocopherols were concentrated in the olein fraction. The fate of the tocopherols during degumming, bleaching and steam refining/deodorizing of Crude palm olein containing 978 ppm total tocopherol was studied. Over the whole refining process only 8% of the tocopherols were lost, 62% of the original tocopherols were retained in the RBD palm olein, while the remaining 30% were concentrated in the fatty acid distillate which contained 7,040 ppm tocopherol.

185 citations


Journal ArticleDOI
TL;DR: In this article, a fungal lipase on a unique macroporous support was demonstrated to catalyze ester synthesis in quantitative yields, employing attractive commercial conditions, and the capability of the catalyst to operate efficiently in reverse under a variety of unnatural, hostile, solvent-containing environments was discussed.
Abstract: The lipase-catalyzed synthesis of ester bonds has been well-documented lately and is of much current commercial interest. Immobilization of a fungal lipase on a unique macroporous support allows not only the ability to operate in non-aqueous media but to catalyze ester synthesis in quantitative yields, employing attractive commercial conditions. Catalyst dose and process configurations will be illustrated. The capability of the catalyst to operate efficiently in reverse under a variety of unnatural, hostile, solvent-containing environments will be discussed. The range of substrates for this immobilized lipase, Lipzome, has been investigated. The enzyme will catalyze ester synthesis with saturated, unsaturated and a variety of branched carboxylic acids. The alcohol specificity for this enzyme also is equally broad. A wide variety of straight-chain, branched and polar alcohols can be substrates. In addition, some examples of alcohol specificity for kinetic isomer resolution will be cited.

183 citations


Journal ArticleDOI
TL;DR: In this article, the authors found that mycelia of arachidonic acid-producing fungi belonging to the genus Mortierella are rich sources of 5,8,11,14,17-cis-eicosapentaenoic acid (EPA).
Abstract: Mycelia of arachidonic acid-producing fungi belonging to the genusMortierella were found to be rich sources of 5,8,11,14,17-cis-eicosapentaenoic acid (EPA). Production of EPA by these fungi was observed only when they were grown at low temperature (6–16 C). EPA comprised 5–20% of the total extractable mycelial fatty acids in most strains tested. No significant accumulation of EPA was observed on incubation at high temperature (20–28 C), at which the other major mycelial C-20 fatty acid, arachidonic acid, was still efficiently produced. In a study on the optimization of the culture conditions for EPA production by a selected fungiM. alpina 20–17, a medium containing glucose and yeast extract as major carbon and nitrogen sources, respectively, was found to be suitable. Periodic feeding of glucose during growth of the fungus and cultivation at high temperature (20 C) during the early growth phase followed by temperature shift to 12 C were found to be effective at increasing mycelial yield and reducing cultural period, respectively. Under the optimal culture conditions, the EPA production reached 0.49 mg/ml of culture broth (29 mg/g dry mycelia). This value accounted for 13.5% of the total fatty acids in the extracted lipids. Other major fatty acids in the lipids were palmitic acid (6.0%, by weight), stearic acid (5.3), oleic acid (6.2), linoleic acid (3.0), γ-linolenic acid (3.5) and arachidonic acid (60.0).

165 citations


Journal ArticleDOI
TL;DR: In this article, the search for an adsorbent to use as the support material for the lipase was discussed, and it was found that hydrophobic microporous powders, membranes and fibers gave the best performance.
Abstract: Enzymatic hydrolysis of triglycerides has been studied as a low energy-consuming alternative to the present steam (Colgate-Emery) process. Cost analysis of the enzymatic process indicates that use of immobilized lipase compares favorably with the present steam process. This paper discusses the search for an adsorbent to use as the support material for the lipase. Hydrophobic microporous powders, membranes and fibers were found to give the best performance, as little of the lipase’s activity was lost upon immobilization. Lipase immobilized on Accurel powder has been studied in various reactor configurations for the hydrolysis of triglycerides. Reactor designs studied include cocurrent and counter-current fixed beds, continuous stirred tank reactors, and the diaphragm reactor. Productivities of the latter two reactor types were 1100 and 1700 kg fatty acid per kg immobilized lipase.

135 citations


Journal ArticleDOI
TL;DR: Monoglycerides have been obtained in 80% yield by enzyme catalyzed hydrolysis of the corresponding triglyceride using a 1,3-specific lipase which leaves the 2- position intact.
Abstract: Monoglycerides have been obtained in 80% yield by enzyme catalyzed hydrolysis of the corresponding triglyceride. The reaction was carried out in an oil-rich microemulsion (L 2 phase) formulated without cosurfactant. Best results were obtained with the anionic surfactant sodium bis(2-ethylhexyl)sulfosuccinate (AOT), isooctane as hydrocarbon component and a molar ratio of aqueous buffer of pH 7 to surfactant of 12. The enzyme used was a 1,3-specific lipase which leaves the 2- position intact. However, the 2-monoglyceride formed slowly undergoes acyl migration to 1-monoglyceride which subsequently is hydrolyzed to glycerol and fatty acid. Optimal reaction time at 35 C reaction temperature was found to be three hr.

135 citations


Journal ArticleDOI
TL;DR: In this paper, the extraction of oil from fixed beds of canola seed (Brassica napus) was studied using carbon dioxide at temperatures and pressures ranging from 25 to 90°C and 10 to 36 MPa, respectively.
Abstract: The extraction of oil from fixed beds of canola seed (Brassica napus) was studied using carbon dioxide at temperatures and pressures ranging from 25 to 90°C and 10 to 36 MPa, respectively. The oil solubility in CO2 was found to be strongly dependent on CO2 pressure and weakly dependent on the system temperature. The highest observed oil solubility was 11 mg/g CO2 and occurred at 36 MPa and 55°C. The manner in which different methods of seed pretreatment (flaking, cooking, pressure rupturing, chopping and crushing) affected the extraction process also was studied. The total amount of oil recovered from the seeds by CO2 extraction was found to be strongly dependent on the pretreatment. No measurable quantity of oil chould be recovered from whole, intact seeds. The amount of oil extractable from flaked and cooked seeds was comparable to that recoverable by conventional hexane extraction.

128 citations


Journal ArticleDOI
TL;DR: In this paper, supercritical fluid CO2 was used to fractionate menhaden oil fatty acid ethyl esters to obtain concentrates of the esters of allcis-5,8,11,14,17-eicosapentaenoic acid (EPA) and all cis-4,7,10,13,16,19-docosahexaenoic amino acid (DHA) and found that the separation of the ethyl Esters of EPA and DHA occurred primarily by carbon number.
Abstract: Supercritical fluid CO2 was used to fractionate menhaden oil fatty acid ethyl esters to obtain concentrates of the esters of allcis-5,8,11,14,17-eicosapentaenoic acid (EPA) and allcis-4,7,10,13,16,19-docosahexaenoic acid (DHA) Separation of the ethyl esters was found to occur primarily by carbon number, thus limiting the degree to which the ethyl esters of EPA and DHA could be concentrated Urea fractionation of whole esters in order to remove saturates, monoenes and dienes prior to fractionation with supercritical fluid CO2 resulted in concentrates of EPA and DHA in purities exceeding 90% Several criteria are given for the selection of crude oils in order to maximize both purity and yield of concentrates

124 citations


Journal ArticleDOI
TL;DR: Calculation shows that the remaining fatty acids are a “basic” composition for these fish oils, with similar totals for saturated (14:0, 16:0), monounsaturated (16:1, 18:1) and polyunsaturated (primarily n-3) fatty acids.
Abstract: It is known that the 20:1 and 22:1 fatty acids of fish oils from temperate and northern latitudes are of exogenous origin. By discounting these two fatty acids, calculation shows that the remaining fatty acids are a “basic” composition for these fish oils, with similar totals for saturated (14:0, 16:0), monounsaturated (16:1, 18:1) and polyunsaturated (primarily n-3) fatty acids. Thus, any of these oils are potential raw materials for urea complexing of acids or esters to give concentrates enriched in eicosapentaenoic and docosahexaenoic fatty acids.

Journal ArticleDOI
TL;DR: In this paper, the volatile compounds formed during autoxidation of methyl linolenate (MLe) at 22-24°C were analyzed by a technique which reveals the flavor compounds having the highest flavor units (ratio of the concentration to the odor threshold).
Abstract: The volatile compounds formed during autoxidation of methyl linolenate (MLe) at 22–24°C were analyzed by a technique which reveals the flavor compounds having the highest flavor units (ratio of the concentration to the odor treshold). After a reaction time of 48 hr, when ca. 20 mol percent of the MLe had been converted into hydroperoxides,trans, cis-2,6-nonadienal followed by 1,cis-5-octadien-3-one,rans,cis-3-5-octadien-2-one andcis-3-hexenal showed the highest flavor units. After 102 hr 1,cis-5-octadien-3-one was by far the most important odor compound, followed bycis-3-hexenal andtrans,cis-2,6-nonadienal.

Journal ArticleDOI
TL;DR: In this article, different fractionation techniques have been evaluated to separate γ-linolenic acid specifically from the other fatty acids present in the oil and, in particular, from α-linorenic acid.
Abstract: Blackcurrant seed oil is known to be one of the richest natural sources of γ-linolenic (allcis-6,9,12-octadecatrienoic) acid, with values of up to 20% of this acid. These concentrations are sufficient for most applications of the oil, but some utilizations require higher concentrations of γ-linolenic acid. Blackcurrant seed oil also contains up to 14%α-linolenic (allcis-9,12,15-octadecatrienoic) acid. Different fractionation techniques have been evaluated to separate γ-linolenic acid specifically from the other fatty acids present in the oil and, in particular, fromα-linolenic acid. Distillation as well as fractionated crystallization at various temperatures did not give any reasonable results. Surprisingly enough, urea fractionation in methanol gives a specific separation ofα- and γ-linolenic acid, whereas stearidonic (allcis-6,9,12,15-octadecatetraenoic) acid, which is present at around 3% in the blackcurrant seed oil, cannot be separated by urea fractionation. Stearidonic acid, like γ-linolenic acid, has a double bond in the Δ6 position, which makes these two acids unique in this respect. This most probably explains their similar behavior toward urea-occlusion. Further semi-industrial preparative HPLC separations allowed us to obtain fractions of 95% γ-linolenic acid.

Journal ArticleDOI
TL;DR: In this article, a low-linolenic acid soybena oil was extracted from the seeds of three such genotypes were processed in laboratory simulations of commercial procedures to finished deodorized oils.
Abstract: During the last 15 years, hybridization and induced mutation breeding of soybeans have been successful in producing an altered fatty acid composition in the extracted oil The objective of those investigations was to produce a low-linolenic acid soybena oil Crude oils extracted from the seeds of three such genotypes were processed in laboratory simulations of commercial procedures to finished deodorized oils Analysis of the fatty acid composition of the three oils showed the linolenic acid content to be 33%, 42% and 48% The stability of these finished oils was compared to that of oil from a soybean variety having a linolenic acid content of 77% and of a commercial hydrogenated-winterized soybean oil (30% linolenic acid) Test and control oils were evaluated by a trained sensory panel initially, after accelerated storage at 60 C and during use at 190 C in room tests Peroxide values were determined at the time of sensory evaluation Results indicated there was no significant difference in flavor stability during storage between test and control oils There was no significant difference, between the oils, in peroxide development during accelerated storage Compared to control oils, the test oils had improved overall room odor intensity scores and lacked the fishy odors of non-hydrogenated soybean oil and the hydrogenated odors of commercial cooking oil

Journal ArticleDOI
TL;DR: In this paper, the authors discuss the commercial utility of immobilized enzymes and discuss the process configurations, scale-up issues and catalyst lifetime/productivity of such enzymes, as well as their application in a continuous column operation.
Abstract: Lipases will catalyze the incorporation of new fatty acids into the triglyceride component of a fat (acidolysis) or can rearrange/redistribute the existing fatty acid radicals in the fat’s triglycerides (transesterification). Both processes can dramatically change the physical characteristics of the fat. Immobilization of the lipase allows for the use of the catalyst in a continuous column operation. Examples illustrating the commercial utility of such immobilized enzymes are presented. Process configurations, scale-up issues and catalyst lifetime/productivity are discussed.

Journal ArticleDOI
TL;DR: The results indicate that the B lipase is formed by partial deglycosylation of the A lipase and that this influences the activity toward emulsions, and that the two enzymes have been immobilized by adsorption.
Abstract: An extracellular lipase produced by fermentation with a selected strain ofMucor miehei has been purified partially in two forms: A and B. The forms have a high degree of antigenic identity and have similar pH-activity profiles with tributyroylglycerol as the substrate with optima at pH 7. The differences are A, in contrast to B, requires activation at alkaline pH before analysis; A binds with concanavalin A more completely than B, the net charges are slightly different at pH 8; the isoelectric points are different. Our results indicate that the B lipase is formed by partial deglycosylation of the A lipase and that this influences the activity toward emulsions. The two enzymes have been immobilized by adsorption. These preparations and the soluble forms were highly specific for primary ester of triacylglycerols (TG), usually hydrolyzed TG of 12:0, 14:0, 16:0 and 18:1 more rapidly than those of 4:0, 6:0, 8:0 and 10:0 in mixtures of monoacid TG (4:0 to 18:1), and were not stereospecific for TG. Immobilization altered the specificity of the preparations somewhat in that slightly more 14:0 and 16:0 were released.

Journal ArticleDOI
TL;DR: The effect of neem leaf extracts on Aspergillus parasiticus growth and aflatoxin biosynthesis was investigated in this paper, where the extracts were prepared by blending 50 g (wet weight) of fresh leaves in one 1 of 10 mM potassium phosphate (pH 7.0) or by boiling the leaves in the buffer.
Abstract: The effect of neem (Azadirachta indica) leaf extracts onAspergillus parasiticus growth and aflatoxin biosynthesis was investigated. The extracts were prepared by blending 50 g (wet weight) of fresh leaves in one 1 of 10 mM potassium phosphate (pH 7.0) or by boiling the leaves in the buffer. Extracts were added to fungal growth media at 1, 5, 10, 20 and 50% (vol/vol) concentrations prior to inoculation. The formulations did not affect fungal growth (i.e., mycelial dry weight) but essentially blocked (>98%) aflatoxin biosynthesis at concentrations greater than 10% (vol/vol). The inhibitory effect was somewhat diminished (60–70%) inhibition) in heated leaf extracts. Volatile components of the extracts were analyzed using capillary gas chromatography/mass spectrometry; the major volatile component was 3-methyl 2-buten-1-ol. However, volatiles from blended leaf extracts did not affect either aflatoxin synthesis or fungal growth. The neem-mediated inhibition appears to involve regulation of secondary metabolism, because once secondary biosynthesis was initiated the inhibitory effect of the neem leaf constituents was lost.

Journal ArticleDOI
TL;DR: In this article, a combination of column chromatography, urea fractionation, high performance liquid chromatography (HPLC) on a C18 reverse phase column and silver nitrate thin layer chromatography was used to detect the C18∶2 isomers.
Abstract: Heat treatment of sunflower oil resulted in the formation of linoleic geometrical and positional isomers. These isomers were isolated using a combination of column chromatography, urea fractionation, high performance liquid chromatography (HPLC) on a C18 reverse phase column and silver nitrate thin layer chromatography (TLC). Each component was submitted to hydrazine reduction and the resulting monoenes to AgNO3-TLC. The resultingcis andtrans fractions were submitted to ozonolysis in BF3-MeOH in order to determine the position of the ethylenic bonds. The major isomers were thecis, trans andtrans, cis 18∶2 Δ9, 12, thetrans, trans 18∶2 Δ9, 12 and somecis, trans, trans, cis andtrans, trans 18∶2 conjugated dienes. Thecis, trans andtrans, cis conjugated dienes were the Δ9, 11, Δ10, 12, Δ11, 13 and Δ12, 14 while thetrans, trans isomers were the Δ9, 11, Δ10, 12 and Δ11, 13. These C18∶2 isomers also were detected in oils collected from restaurants and market vendors.

Journal ArticleDOI
TL;DR: In this article, the optimum pretreatment before hexane extraction of oil was flaking, autoclaving, adjustment to 30% seed moisture including 0.12% enzyme concentration (g enzyme protein/100 g flakes), and incubation for 12 hr at 50 C, followed by drying to 4% moisture.
Abstract: Hydrolysis of three canola cultivars with carbohydrase reduced oil extraction time and increased oil yield. The optimum pretreatment before hexane extraction of oil was flaking, autoclaving, adjustment to 30% seed moisture including 0.12% enzyme concentration (g enzyme protein/100 g flakes), and incubation for 12 hr at 50 C, followed by drying to 4% moisture. Hexane extraction was enhanced by grinding the flakes. The relative order of enzyme efficiency in enhancement of oil extraction was mixed activity enzyme >β-glucanase>pectinase>hemicellulase>cellulase.

Journal ArticleDOI
TL;DR: This paper investigated the volatiles in soybean oil oxidized at different conditions by three capillary gas chromatographic methods: (a) direct injection (5 min heating at 180 C); (b) static headspace (20 min heating 20 C, pressurizing for one min), and (c) dynamic head space (purging 15 min at 180C onto a porous polymer trap, desorbing from trap for five min).
Abstract: To develop new knowledge on undesirable flavors affecting the quality of foods containing polyunsaturated lipids, we investigated the volatiles in soybean oil oxidized at different conditions by three capillary gas chromatographic methods: (a) direct injection (5 min heating at 180 C); (b) static headspace (20 min heating at 180 C, pressurizing for one min), and (c) dynamic headspace (purging 15 min at 180 C onto a porous polymer trap, desorbing from trap for five min). A fused silica column was used with bonded polymethyl and phenyl siloxane phase. At peroxide values between 2 and 10, the major volatile products found in soybean oil by the three methods were pentane, hexanal, 2-heptenal, 2,4-heptadienal and 2,4-decadienal. The intensities of each volatile compound varied with the analytical methods used.

Journal ArticleDOI
TL;DR: This article showed that thermally oxidized compounds had a significant effect on the volatile compound formatiion and molecular oxygen disappearance in the headspace of oil at α = 0.05.
Abstract: Soybean oil purified by silicic acid column chromatography did not contain peroxides, free fatty acids, phospholipids or oxidized polar compounds. The purified soybean oil was thermally oxidized at 180°C for 96 hr in the presence of air. The thermally oxidized compounds (31.3%) were separated from the purified soybean oil by gradient elution silicic acid chromatography. Thermally oxidized compounds contained hydroxyl groups, carbonyl groups andtrans double bonds according to the infrared spectrum. Thermally oxidized compounds were added to soybean oil and purified soybean oil at 0, 0.5, 1.0, 1.5 and 2.0% to study the effects of these compounds on the oxidative stability of oil. The oxidative stabilities of oils were determined by gas chromatographic analysis of volatile compound formation and molecular oxygen disappearance in the headspace of oil bottles. The thermally oxidized compounds showed prooxidant effects on the oxidative stabilities of both refined, bleached and deodorized soybean oil and purified soybean oil. Duncan’s Multiple Range Test showed that thermally oxidized compounds had a significant effect on the volatile compound formatiion and oxygen disappearance in the headspace of oil at α=0.05.

Journal ArticleDOI
TL;DR: It was concluded that rat hepatic microsomal enzymes are induced by dietary DUFO and that the level of induction is influenced by dietary protein level.
Abstract: This study was conducted to investigate the effects of deteriorated used frying oil (DUFO) and dietary protein levels upon the hepatic microsomal drugmetabolizing enzyme system. Fresh soybean oil was subjected to a deep-frying process at 205±5°C for four six-hr periods. The resultant DUFO was incorporated into high protein (HU) (27% lactalbumin) or low protein (LU) (8% lactalbumin) test diets at a 15% level. High protein (HF) and low protein (LF) diets containing fresh soybean oil served as the control. Male Long-Evans young rats fed the test diets for eight weeks showed decreased fat absorption and increased red blood cell (RBC) in vitro hemolysis. The activities of hepatic aminopyrine N-demethylase (AD), aniline hydroxylase (AH), NADPH-cytochrome C reductase (NCD), UDP-glucuronyl transferase (UDPGT) and glutathione S-transferase (GST) as well as cytochrome P-450 content were significantly increased in rats fed the HU diet. However, the AD, AH and GST activities, as well as the cytochrome P-450 content of the LU group, were increased to a lesser extent and significantly lower than those of the HU group. Rats fed the LU diet were the only group that showed significantly elevated serum GOT (E.C. 2.6.1.1, glutamate-oxaloacetate transaminase) and GPT (E.C. 2.6.1.2, glutamatepyruvate transaminase) values. Supplementation of 0.3% DL-methionine to the HU diet further increased GST activity. Unexpectedly, rats fed the low protein control diet (LF) also had raised levels of AD, AH and UDPGT activities as well as in vitro RBC hemolysis. It was concluded that rat hepatic microsomal enzymes are induced by dietary DUFO and that the level of induction is influenced by dietary protein level.

Journal ArticleDOI
TL;DR: In this article, data on soybean yield, protein content and oil content were provided by three crushing companies and showed a definite trend toward lower protein content in soybeans processed and most likely grown in northern versus southern locations (about 34 to 44 N latitude) in 1986-87.
Abstract: Data on soybean yield, protein content and oil content were provided by three crushing companies. There was a definite trend toward lower protein content in soybeans processed and most likely grown in northern versus southern locations (about 34 to 44 N latitude) in 1986–87 (r=0.77). In 1983–86, protein content was generally lower in soybeans processed in Minnesota than in those processed in Indiana and Illinois. Effects of location on oil content and of year on protein and oil content were less clear. Uniform Soybean Tests data over 11 years and four locations (3 in Minnesota, 1 in Illinois) showed significant effects of year on oil content and of location on yield and oil content, but little effect of either on protein content.

Journal ArticleDOI
TL;DR: In this paper, the authors investigated the kinetics of polymorphic transformations in monoacid saturated triglycerides and the influence caused by the presence of certain solid surfactants were investigated.
Abstract: The kinetics of polymorphic transformations in monoacid saturated triglycerides and the influence caused by the presence of certain solid surfactants were investigated. Selected emulsifiers can be incorporated at the level of 10 wt% within the triglyceride, without changing the crystal lattice; on the other hand, their presence affects the heat capacity of the triglyceride and the NMR relaxation time T1. Following the polymorphic transformation both during aging and during heating in the DSC, it was observed that both the mechanism and rate of transformation of the triglyceride strongly depend on the kinetic conditions and on its own chemical structure. In conjunction with these results it also was observed that the effect of the emulsifier is strongly dependent on the transformation conditions. The kinetic effect of the additive on the solid-solid transformation has been found to be strictly associated with its hydrophilic moiety structure; a model of molecular incorporation has been proposed which describes the arrangement of the surfactant molecules parallel to the triglyceride chains and formation of vacancies. The selectivity of the additive concerning its effect of dynamic controller of polymorphic transformations has been explained by its capacity to create hydrogen bonds with the neighboring triglycerides, which was called the “Button Syndrome.” The wide range of different additives and triglycerides used supplied a better understanding of the factors which determine the polymorphic and crystallization behavior in triglycerides.

Journal ArticleDOI
TL;DR: In this paper, a short-path distillation of anhydrous milk fat was performed at temperatures of 245 and 265 C and pressures of 220 and 100 μm Hg.
Abstract: Anhydrous milk fat was fractionated by short-path distillation into four fractions at temperatures of 245 and 265 C and pressures of 220 and 100 μm Hg. Two fractions (LF1 and LF2) were liquid, one fraction (IF) was semi-solid and one fraction (SF) was solid at room temperature. The fractions were characterized by melting temperature profile, solid fat index and triglyceride and fatty acid compositions. The peak melting temperature progressively increased (8.8 to 38.7 C) from liquid to solid fractions. The solid fat content ranged from 0 to 27.5% at 20 C, while native milk fat was 15.4%. The short chain (C24–C34) triglycerides were enriched in the LF1 fraction, long chain (C42–C54) triglycerides were concentrated in the SF fraction, and medium chain (C36–C40) triglycerides in the IF fraction; in the LF2 fraction, though, both short and medium chain triglycerides were enriched. Short chain (C4–C8) fatty acids gradually decreased from liquid to solid fractions and the trend was reverse for long chain (C14–C18) fatty acids, both saturated and unsaturated. The weight average molecular weights and geometric mean-carbon number of milk fat fractions were in the range of 590.7–782.8 and 31.9–46.3, respectively, compared to 729.3 and 41.0, respectively, for native milk fat, suggesting short-path distillation effects a very high degree of molecular weight separation.

Journal ArticleDOI
TL;DR: In this article, polyphenols were extracted from the rape of Israeli olive oil using hexane, acetone and ethanol in a simple sequential procedure yielding three fractions (A,B,C).
Abstract: Polyphenols were extracted from the rape of Israeli olive oil using hexane, acetone and ethanol in a simple sequential procedure yielding three fractions (A,B,C). Fraction A (extracted with hexane) contained few polyphenols (0.05%), while Fraction B (extracted with acetone) and Fraction C (extracted with ethanol) contained about 5% polyphenols each. Fractions B and C were also found to contain the highest ortho-di-phenol concentration (about 3%). The addition of purified Fraction B at a level of 100 ppm to refined olive or soybean oils partially inhibited the oxidative deterioration when the oils were stored in the dark at 100 C.

Journal ArticleDOI
TL;DR: In this article, the structures of oligomers and dimers produced by autoxidation of methyl linolenate and its purified oxidation products were investigated to obtain a better understanding of the mechanism of oxidative deterioration of unsaturated lipids.
Abstract: The structures of dimers and oligomers produced by autoxidation of methyl linolenate and its purified oxidation products were investigated to obtain a better understanding of the mechanism of oxidative deterioration of unsaturated lipids. The dimers were separated by gel permeation chromatography, characterized by molecular weight determinations before and after sodium borohydride reduction, and analyzed by ultraviolet, infrared,1H NMR and fast atom bombardment mass spectrometry. Autoxidation of methyl linolenate at 40 C to peroxide value of 1062 produced 6.8% dimers mainly derived from hydroperoxides, hydroperoxy epidioxides and dihydroperoxides. These dimers were 88% peroxide-linked (C-O-O-C) and 12% ether- (C-O-C) and/or carbon-linked (C-C). Autoxidation of methyl linolenate monohydroperoxides at 40 C produced dimers that were 72% peroxide- and 28% ether/carbon-linked. Thermal decomposition of linolenate hydroperoxides at 150 C gave dimers that were 100% ether/carbon-linked, and catalytic decomposition with ferric chloride-ascorbic acid at room temperature gave dimers with 43% peroxide and 57% ether/carbon linkages. Autoxidation of linolenate hydroperoxy epidioxides at 40 C produced dimers containing hydroperoxy epidioxides, dihydroperoxides and monohydroperoxides joined with peroxide and ether/carbon linkages. Under the same conditions, autoxidation of linolenate dihydroperoxides produced dimers containing dihydroperoxides and hydroperoxy epidioxides joined with peroxide and ether/carbon linkages. These dimers contribute to oxidative and flavor deterioration of polyunsaturated fats in the same way as the hydroperoxide precursors by further decomposition to produce volatile compounds.

Journal ArticleDOI
TL;DR: In this paper, a differential scanning calorimeter (DSC) was used to measure the fractional crystallization of cocoa butter in the presence and absence of sorbitan monostearate at different cooling rates.
Abstract: Cocoa butter was crystallized in the differential scanning calorimeter (DSC) in the presence and the absence of sorbitan monostearate at different cooling rates. The solidification and fusion curves were recorded. It was found that cooling rate affects enthalpies and temperatures of phase transitions. The very slow cooling rate causes a significant decrease in crystallization enthalpy, suggesting that fractionation of glycerides occurs under these conditions. In the presence of sorbitan monostearate 5%, cooling and heating curves of cocoa butter are sharper, the solidification point is higher and the fusion point is slightly lower. Further, in the presence of sorbitan monostearate both crystallization and fusion enthalpies are lower than in pure cocoa butter. The presence of the emulsifier seems mainly to promote the fractional crystallization. Fusion curves after different periods of isothermal crystallization suggest that higher polymorphic forms differ in chemical composition from lower ones, and that the presence of sorbitan monostearate affects the fractionation in the fat.

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TL;DR: In this article, the suitability of Turkish sulphur olive oil monoester as a diesel fuel substitute has been investigated, and some preliminary laboratory tests concerning the applicability of the fuel oil monoeater as an industrial byproduct such as crude fuel oil has been performed.
Abstract: Esterification of Turkish sulphur olive oil with different types of straight- and branched-chain monohydric alcohols has been investigated. Reaction conditions such as temperature and time have been evaluated, and monoester yield has been determined. As the alcohol component, direct application of an industrial byproduct such as crude fuel oil has been investigated. Finally some preliminary laboratory tests concerning the suitability of the fuel oil monoester as a diesel fuel substitute have been performed.

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TL;DR: Synergism in foaming effectiveness, measured by initial foam heights, appears to be related to synergy in surface tension (γ) reduction effectiveness, but not to synergism in γ reduction efficiency or in mixed micelle formation.
Abstract: The relationship between synergism in Ross-Miles foaming and the existence of other types of synergism in binary mixtures of surfactants has been investigated. All studies were conducted in solutions of constant ionic strength (0.1 M NaCl) at 25 and/or 60 C. Six anionic-zwitterionic or anionic-nonionic mixtures and a sodium dodecylbenzenesulfonate (LAS)-soap mixture, all consisting of commercial surfactants, were studied. Synergism in foaming effectiveness, measured by initial foam heights, appears to be related to synergism in surface tension (γ) reduction effectiveness, but not to synergism in γ reduction efficiency or in mixed micelle formation. The LAS-soap system showed negative synergism in foaming effectiveness, correlated with negative synergism in γ reduction effectiveness, the conditions for which are defined. There appears to be no correlation between synergism in foaming efficiency and synergism in either γ reduction efficiency or mixed micelle formation. There also appears to be no unambiguous relationship between foam stability, measured by the ratio of the 5-minute to the initial foam height, and the average area per surfactant molecule at the aqueous solution/air interface.