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1.
Extraction of tocopherols from the deodorized distillate of soybean oil with liquefied petroleum gas
Gisele Maria Buczenko Juarez Souza de Oliveira Oscar Felippe von Meien 《European Journal of Lipid Science and Technology》2003,105(11):668-671
Deodorizer distillate, produced during the last processing step of edible oil refinement, is a mixture of tocopherols, sterols, fatty acids, glycerides, hydrocarbons, water and other materials. The amount of tocopherols in deodorizer distillate is large enough to be considered as raw material for vitamin E preparation. In this work, separation of tocopherols from sterols has been achieved using liquefied petroleum gas (LPG) extraction. LPG was chosen as extraction solvent in order to improve extract recovery and prevent tocopherol degradation. 相似文献
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A supercritical fluid extraction method has been applied to test the feasibility of tocopherol concentration from soybean
sludge with carbon dioxide at temperatures and pressures ranging from 35 to 70°C and 200 to 400 bar, respectively. The supercritical
solubility of the esterified soybean sludge was over 4–6 times greater than that of the original soybean sludge. By a simple
batch-type one-stage method the tocopherols in the esterified soybean sludge could be concentrated up to 40 wt%. The overall
results of the present study show that soybean sludge initially containing about 13–14 wt% tocopherols may require a countercurrent
multistage column to be highly and effectively concentrated. 相似文献
4.
C. Adhikari H. E. Snyder T. W. Kwon P. K. Clark 《Journal of the American Oil Chemists' Society》1992,69(11):1141-1145
By varying the extracting conditions, it may be possible to produce high-quality, low-phosphorus and low-free fatty acid (FFA)
oil extracted from water or mechanically damaged soybeans. The variability in phospholipids and FFA was studied in oil extracted
by an alternative process from undamaged, damaged and aged soybeans subjected to various changes. Forrest and Hutcheson cultivars
were used, and extractions were from finely ground flour rather than from flakes. Freezing caused the maximum increase in
FFA and phosphorus levels compared to other levels in damaged or undamaged soybeans, but the levels were reasonable compared
to flake extraction. Phosphorus and FFA increased when storage temperatures went from 25 to 45°C, extraction temperatures
from 25 to 50°C and moisture of the flour from 6 to 10%. However, the storage time of soybeans with initially high moisture
(20%) did not have a marked influence on FFA and phosphorus levels. Immediately after grinding moisture of the flour elevated
or lowered the phosphorus level to a great extent, although it had little influence on the FFA level. Phosphatidic acid and
phosphatidylcholine were identified as the main phospholipids present when total phosphorus was low in extracted oil. The
time taken for the flour to dry to 6% moisture (after grinding and before it was extracted) was critical. The alternative
extraction process moderated the expected increase in FFA and phospholipids as the result of soybean damage. 相似文献
5.
Quantification of sphingolipids in soybeans 总被引:1,自引:0,他引:1
Soybean is believed to be a rich source of sphingolipids, a class of polar lipids with desirable biological activities. Analytical
methods for sphingolipids vary, and quantitative data for sphingolipids in foods, including soybeans, are scarce. the objectives
of this study were to establish a method for quantification of sphingolipids in soybeans and to determine whether genotype,
stage of maturity, and growing location affect sphingolipid content in soybeans. Separation of neutral lipids and interfering
polar lipids from sphingolipids by saponification, transesterification, and solvent partition was studied. Solvent partition
accompanied by TLC purification was determined to be the most accurate sample preparation method for HPLC quantification of
cerebroside. There were significant differences in cerebroside concentration among genotypes, with a range of 142 to 492 nmol/g
seed (dry wt basis). The differences in cerebroside concentration between immature and mature seeds of one genotype and between
two seed production locations of one genotype were considerable but not statistically significant. 相似文献
6.
腈纶含油率检验方法对比 总被引:1,自引:0,他引:1
使用索氏萃取法、红外光谱分析法、紫外分光光度法对腈纶短纤维含油率进行了测定,对其结果进行了假设检验分析,并比较了3种方法。结果表明:3种方法测定3.20 dtex×102 mm,6.00 dtex×102 mm, 2.78 dtex×64 mm腈纶短纤维的含油率分别为0.358%-0.365%,0.534%~0.550%,0.401%~0.410%; 假设检验分析表明,3种方法均接受假设,其检验水平一致;3种方法各有特点,在进行含油率测试时,可根据条件和需要,合理选择分析方法。 相似文献
7.
G. William Chase Jr. Casimir C. Akoh Ronald R. Eitenmiller 《Journal of the American Oil Chemists' Society》1994,71(8):877-880
A comparison of the responses of an evaporative light-scattering detector (ELSD) and a fluorescence detector for tocopherols
in vegetable oils by high-performance liquid chromatography is presented. The tocopherols were separated from acylglycerols
by gel-permeation chromatography (GPC). The tocopherol fraction was collected off a set of four GPC columns with a mobile
phase of methylene chloride before separation on a normal-phase silica column with a mobile phase of hexane/isopropanol, 99.7∶0.3
(vol/vol). An internal standard of 5,7 dimethyltocol, which was detected by both the ELSD and fluorescence detector, was used
to obtain quantitative data. The fluorescence detector was ten times more sensitive than the ELSD. γ-Tocopherol was the major
tocopherol detected in the vegetable oils studied and ranged from 24.1–93.3 mg/100 g. The amounts of tocopherols found in
the vegetable oils agreed favorably with the literature values. 相似文献
8.
Comparison of membrane extraction with traditional extraction methods for biodiesel production 总被引:1,自引:0,他引:1
Three traditional methods for the refining step in biodiesel production were compared: (i) washing with distilled water; (ii)
washing with acid (HCl); and (3) dissolving and extracting in a solvent (hexane or petroleum ether) and then washing with
distilled water. Biodiesel with a high purity (97.5%) could be obtained by all three methods, but serious emulsification occurred
during the refining processes, which led to high refining losses. A novel refining method was developed by using hollow fiber
membrane extraction, and polysulfone was selected as the most suitable membrane. This process effectively avoided emulsification
during refining and decreased the refining loss. The purity of the biodiesel obtained was about 99%; and other properties,
such as density, kinematic viscosity, water content, and acid value, conformed to the standards. 相似文献
9.
S. Fakirov 《应用聚合物科学杂志》2006,102(2):2013-2014
Modification of a Soxhlet apparatus widely used for extraction is suggested. This modification is aimed at overcoming the main disadvantage of the Soxhlet apparatus for extraction, that the extraction takes place at around room temperature. The modified apparatus allows extraction to be performed with boiling solvent, which has obvious advantages when working with polymers. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 2013–2014, 2006 相似文献
10.
Concentration of sterols and tocopherols from olive oil with supercritical carbon dioxide 总被引:1,自引:0,他引:1
Elena Ibáñez Andrés M. Hurtado Benavides Francisco J. Señoráns Guillermo Reglero 《Journal of the American Oil Chemists' Society》2002,79(12):1255-1260
A process based on the use of a semicontinuous countercurrent supercritical fluid extraction has been developed to isolate
and concentrate minor compounds, such as sterols and tocopherols, from olive oil. In the present work, an evaluation of the
efficiency of different random packing materials (Raschig rings, Dixon rings, Fenske rings, and glass beads) to selectively
separate sterols and tocopherols from olive oil has been performed. Parameters such as recovery, enrichment, and selectivity
vs. TG are discussed. Considering the importance of supercritical fluid extraction as a clean processing technology and the
interest in minor compounds with nutraceutical properties from olive oil, the process studied represents an alternative to
the reuse of low-quality olive oil to extract high added-value products. 相似文献
11.
A novel constant interfacial area cell (NCIAC), by spatially separating the agitation from liquid flow circulation of organic and aqueous two phases, was suggested to obtain detailed kinetic data for Er(III) extraction from chloride medium by 2-ethyl-hexyl-phosphonic acid mono-(2-ethylhexyl) ester (EHEHPA). Different from the traditional Lewis cell and the constant interfacial area cell with laminar flow, the concentrations of Er(III) in organic and aqueous two phases were uniform, and the stability of the interfacial area between the two phases could be controlled effectively. Therefore, the special requirements for the design of agitators in the traditional Lewis cell and the constant interfacial area cell for minimizing the influence of diffusion resistance could be avoided. Experimental results indicated that the extraction kinetics was mainly affected by the aqueous flow rate, interfacial area between organic and aqueous two phases, and the aqueous pH values. An extraction kinetic equation was suggested based on the experimental data. 相似文献
12.
Chunyang Wang Jing Ning Padmanaban G. Krishnan Duane P. Matthees 《Journal of the American Oil Chemists' Society》1998,75(5):609-613
Vitamin E is a natural antioxidant that plays significant roles in food preservation and disease prevention. There are eight
naturally occurring vitamin E isomers (tocols): α-, β-, γ-, and δ-tocopherols and α-, β-, γ-, and δ-tocotrienols. Corn oil
is a major source of vitamin E. Most of the corn oil produced in the United States is a co-product of corn wet-milling. There
is limited knowledge about the effects of corn wet-milling on the retention of these vitamin E isomers. A high-performance
liquid chromatography method was developed for simultaneous determinations of tocols in steeped corn samples. Effects of steeping
conditions (steeping time and SO2 concentration) on retention of tocols in corn were investigated. α-Tocopherol, γ-tocopherol, α-tocotrienol, and γ-tocotrienol
are the predominant vitamin E isomers in the corn variety used in the study. Steeping conditions had little effect on the
concentration of α-tocopherol and α-tocotrienol. However, a higher concentration of SO2 and a shorter steeping time gave a slightly higher γ-tocotrienol content and lower γ-tocopherol content. Corn kernels steeped
in a vitamin C solution had a much higher concentration of the tocols than those steeped in SO2 solution. 相似文献
13.
Biologically produced mucic acid may form crystals before being separated from the biomass. Here we use Soxhlet extraction of fungal biomass to obtain mucic acid that was otherwise lost when separating biomass from the supernatant. Culture supernatant was used to extract the biomass, avoiding dilution of the mucic acid while retaining a cell-free suspension. Soxhlet extraction of biomass recovered 7% of total mucic acid produced at pH 4 and 24% at pH 6. The potential for mucic acid to cyclize to the 1,4-lactone was investigated by solid state NMR, confirming that very little lactone was present after the crystallization step. 相似文献
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Soybean lecithin is used as an emulsifier in food, cosmetic, and pharmaceutical industries. The proportion of individual phospholipids
(PL) and their FA composition may affect the functional properties of lecithin. In this research, lecithins recovered from
four modified soybeans and one commodity soybean, which were processed by extrusion-expelling and conventional solvent extraction,
were analyzed for proportion of PL class and FA composition. HPLC with an ELSD analysis demonstrated that the percentage of
PC in extrusion-expelled lecithin was higher than in solvent-extracted lecithin, whereas the PE content was lower. GC analysis
showed that FA compositions of the PL varied with soybean type. The oil extraction method did not significantly affect FA
composition. Critical micelle concentration tested with a tensiometer showed differences among the lecithins. 相似文献
16.
F. Dionisi J. Prodolliet E. Tagliaferri 《Journal of the American Oil Chemists' Society》1995,72(12):1505-1511
A method involving reversed-phase high-performance liquid chromatography with amperometric detection has been developed for
the analysis of tocopherols and tocotrienols in vegetable oils. The sample preparation avoids saponification. Recoveries of
α-tocotrienol and γ-tocotrienol in extra virgin olive oil were 97.0 and 102.0%, respectively. No tocotrienols were detected
in olive, hazelnut, sunflower, and soybean oils, whether virgin or refined. However, relatively high levels of tocotrienols
were found in palm and grapeseed oils. This method could detect small quantities (1–2%) of palm and grapeseed oils in olive
oil or in any tocotrienol-free vegetable oil and might, therefore, help assess authenticity of vegetable oils. 相似文献
17.
The extraction of ethanol with the solvents of aldehydes mixed with m-xylene was studied for the bioethanol concentration process.Furfural and benzaldehyde were selected as extraction solvents,with which the solubility of water is small,expecting large distribution coefficient of ethanol.The liquid–liquid two-phase region was the largest with m-xylene solvent,followed by benzaldehyde and furfural.The region of two liquid–liquid phase became larger with the mixed solvent of m-xylene and furfural than that with furfural solvent.The NRTL model was applied to the ethanol–water–furfural–m-xylene system,and the model could well express the liquid–liquid equilibrium of the system.For any solvent used in this study,the separation selectivity of ethanol relative to water decreased as the distribution coefficient of ethanol increased.The separation selectivity with m-xylene was the largest among the employed solvents,but the distribution coefficient was the smallest.The solvent mixture of furfural and m-xylene showed relatively high distribution coefficient of ethanol and separation selectivity,even in the higher mass fraction of m-xylene in the solvent phase.The ethanol extraction with a countercurrent multistage extractor by a continuous operation was simulated to evaluate the extraction performance.The ethanol content could be concentrated in the extract phase with relatively small number of extraction stages but low yield of ethanol was obtained. 相似文献
18.
Jeffrey A Galloway 《Polymer》2004,45(2):423-428
The effect of sample size on the results of solvent extraction measurements for detecting cocontinuity in polymer blends was investigated. Poly(ethylene oxide)/polystyrene (PEO/PS) blend samples of several thicknesses were analyzed by removing the PEO phase using water extraction. The experimental degree of continuity was shown to have a linear dependence on the reciprocal of sample thickness. A model is proposed to explain this dependence and to allow the bulk or true degree of continuity to be determined. Measurement of the bulk degree of continuity is useful for understanding properties of cocontinuous polymer blends such as electrical conductivity, impact strength, or tensile strength. 相似文献
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Three different process alternatives for the production of soybean oil by supercritical carbon dioxide extraction were analyzed.
The first two processes were organized according to the classical scheme, based on high-pressure extraction followed by separation
induced by pressure reduction. Different techniques were used to recover the solvent in these two schemes, in the liquid and
in the gas phases, respectively. The third alternative was based on an isobaric scheme—the oil, extracted at high pressure,
was separated by chainging the temperature in the separator. In a further improvement, a technique for the heat transfer network
integration was added to all the process schemes. The different schemes were used to establish the process configuration that
can produce a lower operating cost for soybean oil extraction. Operating costs were considered on an industrial scale to carry
out a screening of the different alternatives. The operating cost of these plants were then compared with the hexane extraction
process. A substantial reduction in the specific costs was obtained in the case of heat transfer integration, and the operating
costs fell in the same range as conventional extraction plants. 相似文献