Evaluation of polyoxyethylene glycol esters of castor, high-erucic acid rapeseed, and soybean oils

The properties of polyoxyethylene glycol esters having different molecular weights and based upon different oils were studied for solubility, emulsification, and other surfactant properties. Three different oils as starting materials for the preparation of surfactant esters were evaluated. Solubility in water, isopropanol, mineral oil, and propylene glycol were evaluated as well as emulsification properties. The hydrophile-lipophile balance system proved to be a good tool to predict emulsification properties. Surprisingly, high-erucic rapeseed oil and castor surfactants were similar in solubility, and soy-based surfactants were found to be less water soluble.     

Fatty acid composition ofcuphea seed oils

Nineteen species of 10 taxonomic sections ofCuphea were analyzed for fatty acid composition of the seed oils. Two sections of the genus,Trispermum andPseudocircaea, previously unreported, are included. Lauric acid is the major component of the seed oil in seven of the species surveyed; capric andmyristic each predominate in five. Linolenic acid, previously thought to be only a trace component ofCuphea seed oils, is the major constituent of two species. Two others are rich in linoleic acid, another minor component of mostCupbea oils.     

Fatty acid esters of glycidol in refined fats and oils

Discrepancies in the analysis of 3‐chloropropane‐1,2‐diol (3‐MCPD) esters can be explained by the hypothesis that in some refined oils significant amounts of fatty acid esters of glycidol (glycidyl esters) are present in addition to 3‐MCPD esters. Glycidyl esters were separated from triacylglycerols by gel permeation chromatography (GPC) and detected by gas chromatography‐mass spectrometry (GC‐MS). Six samples of palm oil and palm oil‐based fats were analyzed by GPC and GC‐MS. In chromatograms of all samples, significant peaks, retention time and mass spectra in conformity with self‐synthesized glycidyl palmitate and glycidyl oleate were detectable. Quantification of individual glycidyl esters was not possible because of a lack of pure standards. Concentration of ester‐bound glycidol in different samples of fats and oils was estimated using an indirect difference method. Glycidyl esters could be detected only in refined, but not in crude or native, fats and oils. The highest concentrations were detected in palm oil and palm oil‐based fats. In a palm oil sample, glycidyl ester concentration varied according to different deodorization parameters, temperature, and time, while 3‐MCPD ester concentration was relatively constant, indicating that mitigation of glycidyl esters possibly may be achieved by optimizing refining parameters.     

Fatty acid composition of Iranian citrus seed oils

Fatty acid compositions of seed oils from eight Iranian citrus fruits were determined. The ranges of values for major fatty acids were 21.8–29.4% palmitic, 3.1–7.60% stearic, 0.3–1.3% palmitoleic, 23.5–32.3% oleic, 33.5–39.8% linoleic, and 3.1–7.6% linolenic. Low amounts (up to 0.1%) of myristic and arachidic acids and traces of a few unidentified ones constituted minor fatty acids.     

Fatty acid composition of oleaster pulp and pit oils

Fatty acid compositions of oleaster pulp and pit oils were determined by gas chromatography in 4 samples of different varieties. Pit oils were highly unsaturated, containing >90% linoleic, oleic, and linolenic acids, as well as traces of palmitoleic acid. Saturated fatty acids consisted of palmitic and stearic acids with traces of arachidic acid. Pulp oils showed fatty acid compositions entirely different from that of pit oils. They contained 9 saturated fatty acids, C₁₂ to C₂₄, some of them with high quantities, up to 34.9%, of the total fatty acids. Unsaturated fatty acids, mainly oleic and linoleic, with low quantities of palmitoleic and linolenic acids composed about one-third of the total fatty acids.     

Fatty acid composition of some pine seed oils

The fatty acid composition of seeds from seven species of the genusPinus (P. pinaster, P. griffithii, P. pinea, P. koraiensis, P. sylvestris, P. mughus, andP. nigra) was established. Pine seeds are rich in oil (31–68% by weight) and contain several unusual polymethylene-interrupted unsaturated fatty acids with acis-5 ethylenic bond. These are thecis-5,cis-9 18:2,cis-5,cis-9,cis-12 18:3,cis-5,cis-11 20:2, andcis-5,cis-11,cis-14 20:3 acids, with a trace ofcis-5,cis-9,cis-12,cis-15 18:4 acid. Their percentage relative to total fatty acids varies from a low of 3.1% (P. pinea) to a high of 30.3% (P. sylvestris), depending on the species. The majorcis-5 double bond-containing acid is generally thecis-5,cis-9,cis-12 18:3 acid (pinolenic acid). In all species, linoleic acid represents approximately one-half the total fatty acids, whereas the content of oleic acid varies in the range 14–36% inversely to the sum of fatty acids containing acis-5 ethylenic bond. The easily available seeds fromP. koraiensis appear to be a good source of pinolenic acid: their oil content isca. 65%, and pinolenic represents about 15% of total fatty acids. These values appear to be rather constant.Pinus pinaster, which is grown on several thousand acres in the southwest of France, is an interesting source ofcis-5,cis-11,cis-14 20:3 acid (7% in the oil, which isca. 35% of the dehulled seed weight), an acid sharing in common three double bonds with arachidonic acid. Apparently,P. sylvestris seed oil contains the highest level ofcis-5 double bond-containing acids among pine seed oils that have ever been analyzed.     

Fatty acid composition in seed oils of some onagraceae

The seeds ofOenothera picensis, O. indecora, Ludwigia longifolia andL. peruviana (Onagraceae) contained 18.3, 16.4, 13.9 and 10.1% oil, respectively. Chromatographic analyses showed high levels of linoleic acid (>71.5%) in the seed oils.     

Fatty acid composition ofThalictrum L. seed oils

The fatty acid composition of five representatives of theThalictrum L. genus of the plant familyRanunculaceae has been investigated. The fatty acids include mainly acids with double bonds in thetrans-5 position (about 60%). Although the main component of the fatty acids is a triene acid (trans-5,cis-9,cis-12-octadecatrienoic acid), the oils investigated are semidrying.     

Membrane degumming of crude soybean and rapeseed oils

Membrane separation in edible oil processing is a potential area for energy savings. However, technical and operating-cost-related barriers have impeded the successful application of membrane separation in food processing. Studies were undertaken with soybean and rapeseed oils in a magnetically stirred flat-membrane batch cell with two types of composite polymeric membranes at 3 MPa pressure and at a constant temperature of 40°C. The membranes were NTGS-1100 and NTGS-2100, and used silicon as the active layer and polysulfone and polyimide as support layers, respectively. The membrane selectively rejected phospholipids, the content being less than 240 mg/kg in the permeate without any pretreatment or dilution of crude oil with organic solvent. Long-term studies up to 97 days with soybean oil at two different pressures, 2 and 3 MPa, showed that the rejection of phosphatides was above 96% in most permeates. The permeate flux remained nearly constant but must be improved.     

Fatty acid composition inCuphea seed oils from brazil and nicaragua

Seed oils ofCuphea are characterized by a diverse assemblage of fatty acid patterns emphasizing short- and medium-chain fatty acids. For this report, seed oils of 19 populations from 14 species were analyzed. Thirteen species are from Brazil and one from Nicaragua. Fatty acid compositions of oils of eight species are reported for the first time. Lauric acid predominates in 10 species, myristic acid in one, and linoleic acid in three. Small amounts of C20:0 and C20:1 are recorded in one species. The major fatty acid for each taxonomic section is consistent with that reported earlier as characteristic of the section. Seed oil compositions of species previously reported from North or Central American populations are comparable to those of the Brazilian populations.     

Flavor and oxidative stability of soybean,sunflower and low erucic acid rapeseed oils

Three samples each of soybean, sunflower and low erucic acid rapeseed (LEAR) oils were evaluated for flavor and oxidative stability. The commercially refined and bleached oils were deodorized under identical conditions. No significant differences were noted in initial flavor quality. After storage at 25°C or 60°C in the dark, soybean oils—with or without citric acid—were more stable than either sunflower or LEAR oils. However, in the presence of citric acid, soybean oils were significantly less stable to light exposure than either LEAR or sunflower oils. In contrast, in the absence of citric acid, soybean oils were significantly more light stable than LEAR oils. In either the presence or absence of citric acid, sunflower oil was significantly more stable to light than soybean oil. Analyses by static headspace gas chromatography showed no significant differences in formation of total volatile compounds between soybean and LEAR oils. However, both oils developed significantly less total volatiles than the sunflower oils. Each oil type varied in flavor and oxidative stability depending on the oxidation method (light vs dark storage, absence vs presence of citric acid, 100°C vs 60°C). Presented at the annual meeting of the Canadian Section of AOCS, held in October 1987 in Winnipeg, Manitoba, Canada.     

Fatty acid composition of individual plasma steryl esters in phytosterolemia and xanthomatosis

The bulk of the plasma plant sterol in phytosterolemia occurs in the esterified form and is carried mostly in the low and high density lipoproteins. We have determined the fatty acid composition of the individual plasma steryl esters from a newly discovered subject with phytosterolemia and xanthomatosis. For this purpose the intact steryl esters were subject to high temperature gas liquid chromatography (GLC) on a polar capillary column, which separated the major esters on the basis of molecular weight and degree of unsaturation of the fatty acids. The saturated and unsaturated sterols esterified to saturated, monoenoic, dienoic and tetraenoic fatty acids were identified by GLC analysis of the sterol moieties of the corresponding AgNO₃-TLC fractions of the steryl esters. The GLC results were confirmed by reversed phase high performance liquid chromatography combined with mass spectrometry via direct liquid inlet interface. It was found that, in general, each fatty acid was esterified to the same complement of sterols, and that the esterified sterols possessed a composition comparable to that of the free plasma sterols, which was comprised of about 75% cholesterol, 6% campesterol, 4% 22,23-dihydrobrassicasterol and 15% β-sitosterol. The fatty acid composition of the steryl esters differed from that of the 2-position of the plasma phosphatidylcholines, which contained significantly less palmitic and oleic and more linoleic acid. On the basis of these results and a review of the literature it is suggested that the plasma cholesteryl and plant steryl esters in phytosterolemia originate from both synthesis in plasma via the lecithin-cholesterol acyltransferase and synthesis in tissues via the acylCoA-cholesterol acyltransferase.     

Fatty acid composition of oils extracted from Canadian weed seeds

The fatty acid composition of the diethyl ether extract from nine varieties of Canadian weed seeds is reported. Fatty acid compositions forRumex pseudonatronatus L. Borbus,Setaria viridis L. Beauv., andChenopodium album L. have not been previously reported. Contribution no. 358, Grain Research Laboratory, Canadian Grain Commission.     

Fatty acid composition of capsicum oils by gas liquid chromatography

The fatty acid composition of oils extracted from various parts (pericarp, seeds and stem) of the fruit ofCapsicum and from samples of Greek red pepper itself were obtained by gas liquid chromatography. Samples from three different varieties ofCapsicum annuum, cultivated in the region of Almopia, Greece, were taken from two crops (1967, 1968) and examined. The results are discussed. No characteristic differences in fatty acid composition of the corresponding samples of the parts ofCapsicum fruit of the three Greek varieties were noticed and there was no difference between the two crops. However, considerable differences in fatty acid composition between Greek and American varieties were observed, probably due to climatic conditions. Presented at the Association of Greek Chemists Meeting, Athens, 1970.     

trans-Polyunsaturated fatty acids in French edible rapeseed and soybean oils

The fatty acid compositions of rapeseed and soybean oils marketed in France have been determined by gas liquid chromatography on a fused-silica capillary column coated with a 100% cyanopropyl polysiloxane stationary phase. Under the operating conditions employed, methyl esters of linolenic acid geometrical isomers could be separated and quantitated easily without any other complementary technique. With only one exception, all samples under study (eight salad oils and five food samples) contain geometrical isomers of linolenic acid in measurable, although variable, amounts. Totaltrans-18:3 acids may account for up to 3% of total fatty acids. This value corresponds to a degree of isomerization (percentage oftrans isomers relative to total octadecatrienoic acids) of 30%. Examination of our data indicates that the distribution pattern of linolenic acid geometrical isomers does not depend on the degree of isomerization. The two main isomers always have thec,c,t and thet,c,c configurations. These isomers occur in the almost invariable relative proportions of 47.8±1.7% and 41.1±1.0%, respectively. The third mono-trans isomer is present in lower amounts−6.5±0.7%. The only di-trans isomer that can be quantitated with sufficient accuracy is thet,c,t isomer (4.9±1.5%). Mono-trans isomers of linoleic acid are also present in these oils. However, their maximum percentages are lower than those determined for linolenic acid geometrical isomers. In the oils showing the highest degrees of isomerization,trans isomers of linoleic acid account for 0.5% (rapeseed oils) and 1% (soybean oils) of total fatty acids. Taking into account all data, it would appear that the probability of isomerization of linolenic acid is about 13–14 times that of linoleic acid.     

Oxidative and flavor stabilities of soybean oils with low-and ultra-low-linolenic acid composition

The effects of linolenic acid (18∶3) concentration, combined with TBHQ addition, temperature, and storage time, on the oxidative and flavor stabilities of soybean oils (SBO) were evaluated. During storage under fluorescent light at both 21 and 32°C, the SBO with ultra-low-18∶3 concentration (1.0%, ULSBO) generally had greater oxidative stability than did SBO with low-18∶3 concentration (2.2%, LLSBO). The ULSBO had about half the p-anisidine value of LLSBO throughout storage. Although the ULSBO initially had significantly greater PV and poorer (lower) sensory scores for overall flavor quality than did LLSBO, significant differences disappeared with storage. The ULSBO had a lower content of polar compounds and greater oil stability indices than did LLSBO when TBHQ was present. All oils were more oxidatively stable with TBHQ addition, but the TBHQ addition did not result in improved flavor stability early in storage. In all tests, oils stored at 32°C were less stable than oils stored at 21°C. The TBHQ had a better antioxidant capacity when the 18∶3 concentration was lower. The retardation effect of TBHQ on lipid oxidation and the improved stability of ULSBO over LLSBO were more easily detected when the storage temperature was higher.     

Bleaching rapeseed and soybean oils with synthetic adsorbents and attapulgites

Efficiencies of synthetic adsorbents and attapulgites in bleaching alkali-refined rapeseed and soybean oils ranged from 13–53% and 93–97%, respectively. The Freundlich equation was more applicable than the Langmuir equation to the experimental adsorption isotherms of β-carotene on attapulgites. Bleaching with attapulgites reduced tocopherols by 12.5–29.5% in rapeseed oil and by 18.9–44.8% in soybean oil. Cosmetic-grade attapulgite was superior to the others in bleaching efficiency, equilibrium amount adsorbed and removal of free fatty acids.     

Chromatographie analysis of seed oils. Fatty acid composition of castor oil

The fatty acid composition of a number of domestic and foreign castor oils was determined by consecutive column and gas-liquid Chromatographic analysis. After saponification of the oils and removal of the unsaponifiables, the nonhydroxy, monohydroxy, and dihydroxy acids were fractionated by partition chromatography on silicic acid. The amount of acid in each fraction was determined by titration or weighing. Gravimetric data were in good agreement with the titrimetric data. The acids obtained by saponification were converted to methyl esters with diazomethane and similarly subjected to partition chromatography. The methyl esters from various fractions were analyzed by gas-liquid chromatography. Components were tentatively identified by their comparative retention times and confirmed Presented at the AOCS meeting in Chicago, 1961. A laboratory of the Western. Utilization Research and Development Division, Agricultural Research Service, U.S.D.A.