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1.
Samples of freshly ground corn kernels and freshly ground rolled oats were extracted via pressurized liquid extraction (accelerated solvent extraction) using four different organic solvents [hexane, methylene chloride
(also known as dichloromethane), isopropanol, and ethanol] at two temperatures (40 and 100°C). Lipid yields varied from 2.9
to 5.9 wt% for ground corn and from 5.5 to 6.7 wt% for ground oats. With ground corn, more lipid was extracted as solvent
polarity was increased, and for each individual solvent, more lipid was extracted at 100°C than at 40°C. With ground oats,
the same temperature effects was observed, but the solvent polarity effect was more complex. For both corn and oats, methylene
chloride extracted the highest levels of each of the nonpolar lipid classes. In general, for both corn and oats, icnreasing
solvent polarity resulted in increasing yields of polar lipids, and for each solvent, more of each lipid class was extracted
at 100°C, than at 40°C. Among the lipids in corn extracts, the phytosterols may be the most valuable, and total phytosterols
ranged from about 0.6 wt% in the hot ethanol extracts to about 2.1 wt% in the hot hexane and methylene chloride extracts.
Total phytosterols in all oat extracts were about 0.1 wt%. Digalactosyldiacylglycerol was the most abundant polar lipid in
the oat extracts; its levels ranged from 1.6 wt% in the cold hexane extracts to 4.3 wt% in the hot ethanol extracts. 相似文献
2.
M. P. Hojilla-Evangelista D. J. Myers L. A. Johnson 《Journal of the American Oil Chemists' Society》1992,69(3):199-204
An investigation was conducted to identify and characterize protein extracted by 45% ethanol:55% 0.1 M NaOH from flaked, defatted,
undegermed corn (Zea mays L.) during Sequential Extraction Processing (SEP). This new approach to corn milling, SEP, recycles the ethanol produced
from the fermentation of cornstarch to upstream steps of protein extraction and the simultaneous extraction of corn oil and
dehydration of the ethanol. About 10% of the protein was extracted by ethanol during counter-current-percolation oil extraction.
Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and amino acid analysis identified this protein as zein.
Nearly 65% of the total protein was recovered by the process in the protein extraction step from soft dent corn (Pioneer 3377),
medium-hard dent corn (Pioneer 3732) and high-lysine corn. The freeze-dried solids of the ethanol/alkali extracts from these
corn hybrids contained about 80% crude protein (db). The amino acids were present in quantities similar to those in whole
corn and markedly higher than those in corn gluten meal. These results indicate that SEP produces high-quality protein suitable
for food and industrial uses.
Paper presented at the Symposium on Oilseed Processing for Edible Food and Feed Products, 82nd Annual Meeting of the AOCS,
May 12–15, 1991.
Research Associate, Assistant Professor, and Professor, respectively. 相似文献
3.
H. Sun D. Wiesenborn P. Rayas-Duarte A. Mohamed K. Hagen 《Journal of the American Oil Chemists' Society》1995,72(12):1551-1555
Amaranth seed (Amaranthus hypochondriacus cv. K432) was processed to obtain oil, reported to be a promising source of squalene. The amaranth seed was ground using
a stone mill, then separated into oil-rich embryonic tissue (or “bran”) and starchy perisperm. Amaranth bran was much more
stable than rice bran when free fatty acid (FFA) content and peroxide value were monitored. Milling at a gap of 0.755 mm did
not result in excessive damage to the starch in the perisperm fraction and yielded a bran fraction that contained more than
three-fourths of the oil and a starchy fraction consisting of more than two-thirds of the seed weight. The bran particles
were too fine for effective bench-scale extraction of the oil. Consequently the bran was extruded into collects prior to extraction.
Two extrusion settings were evaluated regarding the rate of moisture injection, while the bran feed rates were constant. There
was no significant difference in appearance or size between the two dried collets. Collets were extracted with hexane using
an Armfield Extraction/Desolventizing Unit (Model FT 29, Armfield, Ltd., Hampshire, England). Oil recovery averaged 97.7 and
80.0%, respectively. Oil was extracted at high yield from the bran when the bran was extruded into collets. Oil can be obtained
as a coproduct of amaranth starch by milling and separating the fractions of amaranth seed. Milling, extrusion, and extraction
did not decrease significantly the squalene content in amaranth oil, but increased FFA content and peroxide value and changed
tocopherol content of the oil. 相似文献
4.
Selective extraction of phosphatidylcholine from lecithin by supercritical carbon dioxide/ethanol mixture 总被引:10,自引:0,他引:10
Leyla Teberikler Sefa Koseoglu Aydin Akgerman 《Journal of the American Oil Chemists' Society》2001,78(2):115-120
Selective extraction of phosphatidylcholine (PC) from deoiled soybean lecithin using supercritical fluid (SCF) mixtures of
carbon dioxide (CO2) and ethanol was studied at moderate pressures. Temperature was varied between 60 and 80°C at pressures of 17.2 and 20.7
MPa. Ethanol was added as co-solvent to supercritical CO2 at the levels of 10 and 12.5 wt%. Constant rate of extraction of the individual phospholipids (PL) was observed for 150 min
during which the extractions were carried out. Pressure and ethanol fraction had a positive effect on the selective extraction
of PC, whereas temperature had a negative effect. Under all the conditions studied, the extracts were mainly composed of PC
while the extraction of the other PL was very low. Extraction at 60°C and 20.7 MPa with 10 wt% ethanol/90 wt% CO2 SCF mixture resulted in 95% selectivity to PC. 相似文献
5.
David Villanueva Bermejo Pilar Luna Marina S. Manic Vesna Najdanovic-Visak Guillermo Reglero Tiziana Fornari 《Food and Bioproducts Processing》2013,91(4):303-309
This paper reports experimental data on the pressurized liquid extraction of caffeine from green coffee beans and green tea leaves using ethyl lactate (ethyl 2-hydroxy-propanoate). This solvent is a new bio-renewable agrochemical solvent, naturally produced by fermentation from corn derived feedstock, which has been recently considered as a very suitable and environmental benign solvent for food industrial applications.Static extraction assays (one step during 10 min) were carried out in an Accelerated solvent extraction (ASE) system at three different extraction temperatures, namely 100, 150 and 200 °C. Extraction yield and caffeine recovery were determined and compared with those obtained when using other liquid solvents, such as ethyl acetate or ethanol. High recovery of caffeine (≈60%) was found in the extracts produced using ethyl lactate, which demonstrates the potential use of this green solvent for the extraction of caffeine from different vegetable sources. 相似文献
6.
Mono-carboxylic, straight-chain fatty acids are present in extracts of lignite and subbituminous coal (0.4–1.0 wt%, daf basis), but not in those of a bituminous coal. They are removed with nearly equal ease by both solvent and supercritical gas (SCG) extraction. Octacosanoic acid is the major constituent, and values of the carbon preference index (even over odd) lie between 2 and 6. Solvent extraction of the coals also removes small quantities (< 0.08 wt%) of straight-chain alkanes which are closely related in composition to the straight-chain fatty acids and are probably derived from them during maturation. However, previous SCG extraction of the coals yielded much larger quantities of straight-chain alkanes (0.3–0.7 wt%). Pyrolysis experiments with a lignite fatty acid fraction and with tetracosanoic acid show that these acids largely survive SCG extraction and, therefore, are not the main source of the relatively large quantity of straight-chain alkanes in these extracts. 相似文献
7.
Ioana Asofiei Ioan Calinescu Adrian Trifan Iulia Gabriela David 《Chemical Engineering Communications》2016,203(12):1547-1553
Extraction of polyphenols from sea buckthorn leaves using microwave-assisted extraction (MAE) is described. The influence of different parameters on the extraction process (reactor type, stirring rate, extraction time, temperature, ethanol/water ratio) was studied. The polyphenolic extracts were analyzed in order to determine the total phenolic content (TPC) either by the Folin–Ciocalteu method or by differential pulse voltammetry (DPV), and the concentration of the main polyphenolic compounds by high-performance liquid chromatography (HPLC). The specific microwave energy was also determined. MAE resulted in a shorter extraction time (7.5 versus 30 min for the conventional method). The best results for MAE were obtained at a temperature of 90°C, using a solvent/plant ratio of 20/1 and 50% ethanol in the extraction solvent. The highest values of antioxidant capacity were obtained for polyphenolic extracts resulted from microwave extraction. 相似文献
8.
Corn oil was extracted from whole ground corn using ethanol as the solvent. The yield of oil was measured as a function of
temperature, time of extraction, solvent-to-solids ratio, and ethanol concentration. Optimal conditions were a solvent-to-solids
ratio of 4 mL/g corn, an ethanol concentration of 100%, 30 min of extraction time, and a temperature of 50°C. Under these
conditions, a single batch extraction yielded ≈3.3 g oil/100 g corn, equivalent to 70% extraction efficiency. A three-stage
extraction, where the same corn was exposed to fresh ethanol, resulted in a yield of ≈4.5 g/100 g corn (2.5 lb/bu of corn),
equivalent to 93% recovery of the oil in corn. When anhydrous ethanol was used to repeatedly extract fresh corn, moisture
was absorbed linearly by ethanol from the corn in successive stages, which, in turn, decreased oil yield and increased nonoil
components in the extract. 相似文献
9.
朱宝伟 《化学工业与工程技术》2014,(3):4-8
微波条件下,研究了在乙醇抽提神府煤中加入氯化锌对其结果的影响。采用气相色谱/质谱联用的方法分析了乙醇和乙醇-氯化锌抽提物的组成;利用傅里叶红外光谱技术分析了神府脱矿物质煤、乙醇抽余煤和乙醇-氯化锌抽余煤的结构。分析结果显示:在乙醇溶剂中添加少量的氯化锌,其抽提物的组成发生了改变;乙醇-氯化锌抽余煤与原脱矿物质煤和乙醇抽余煤相比,芳环吸收强度降低,表明在抽提过程中可能伴随着烷基化反应的发生。 相似文献
10.
In the United States, sorghum is primarily used for animal feed and ethanol production but has potential to provide value-added coproducts including waxes and oil. The surface of sorghum contains 0.1–0.4% wax; however, wax extraction from whole kernels before fermentation may not be economical. An alternative method for this extraction could be facilitated through decortication, abrasion of the surface to remove bran. Decortication increases the starch content of decorticated sorghum, potentially improving ethanol yields, while concentrating wax and oil to the bran. Typically, oil (triacylglycerols) and waxes are extracted from bran in one extraction and waxes are precipitated from oil using cold temperatures then filtration. This research compared traditional fractionation (simulated with a two-step, single-temperature extraction) to a two-step, dual-temperature extraction, whereby oil is first extracted at room temperature and then waxes at elevated temperature. Extractions were performed using an accelerated solvent extractor with hexane or ethanol as solvents. Ethanol extraction showed greater yields (~15% w/w) compared to those of hexane (~11% w/w) because polar materials were extracted. Using hexane, the two-step, dual-temperature fractionation separated waxes from oils via the temperature of extraction solvent with similar purity to the traditional method that fractionated via cold precipitation and filtration. For ethanol, the traditional single-step method fractionated with higher wax purity but lower oil purity compared to the two-step, dual-temperature fractionation. 相似文献
11.
A preparative-scale supercritical fluid extraction/supercritical fluid chromatography (SFE/SFC) procedure has been developed
for the removal of oil from corn bran to obtain fractions enriched with free sterols and ferulate-phytosterol esters (FPE).
Operational parameters from an analytical-scale supercritical fluid fractionation technique were translated to and optimized
on a home-built, preparatory-scale SFE/SFC apparatus. SFE was performed at 34.5 MPa and 40°C using supercritical carbon dioxide.
These conditions did not result in exhaustive extraction of the corn bran, but yielded about 96% of the available oil. SFC
was conducted in three steps, followed by reconditioning of the sorbent bed. Preparative-scale SFE/SFC of corn bran produced
a fraction enriched greater than fourfold in free sterols and 10-fold in FPE, suggesting that such a scheme could be used
industrially to produce a functional food ingredient. 相似文献
12.
Phytosterols are hypocholesterolemic. Like corn fiber oil, the lipid extracts of certain cereal by-products may be rich sources
of these health-promoting compounds. The objective of this research was to examine the phytosterol content and composition
of various cereal by-products. Total lipids in rice bran, wheat bran, wheat germ, durum wheat (bran and germ mixture), oat
bran, oat hull, and corn fine fiber were extracted, and the sterol profiles of the extracted lipids were analyzed by GC. Rice
bran contained the most lipids (22.2%), followed by wheat germ, durum wheat, oat bran, wheat bran, and oat hull; corn fine
fiber contained the least amount of lipids (1.7%). Sitosterol, campesterol, and stigmasterol were the major phytosterols in
these lipid extracts, whereas brassicasterol was detected only in wheat samples. Rice bran oil contained considerable amounts
of cycloartenol and 24-methylenecycloartanol, which were unique to these samples. Total sterol concentrations in extracted
lipids were similar for rice bran, wheat bran, wheat germ, and durum wheat (21.3–15.1 mg/g), but they were very low in oat
bran lipids and oat hull lipids (3.4 and 8.2 mg/g, respectively). Corn fine fiber lipids contained the highest amount of sterols
(48.3 mg/g). Rice bran appears to be the best source of phytosterols, with the highest oil content and high concentration
of sterols. 相似文献
13.
Darrell Sparks Rafael Hernandez Mark Zappi Dean Blackwell Trey Fleming 《Journal of the American Oil Chemists' Society》2006,83(10):885-891
Extraction of rice bran lipids was performed using supercritical carbon dioxide (SC−CO2) and liquid propane. To provide a basis for extraction efficiency, accelerated solvent extraction with hexane was performed
at 100°C and 10.34 MPa. Extraction pressure was varied for propane and SC−CO2 extractions. Also, the role of temperature in SC−CO2 extraction efficiency was investigated at 45,65, and 85°C. For the SC−CO2 experiments, extraction efficiencies were proportional to pressure and inversely proportional to temperature, and the maximal
yield of oil achieved using SC−CO2 was 0.222±0.013 kg of oil extracted per kg of rice bran for conditions of 45°C and 35 MPa. The maximal yield achieved with
propane was 0.224±0.016 kg of oil per kg of rice bran at 0.76 MPa and ambient temperature. The maximum extraction efficiencies
of both SC−CO2 and propane were found to be significantly different from the hexane extraction baseline yield, which was 0.261±0.005 kg
oil extracted per kg of rice bran. A simulated economic analysis was performed on the possibility of using SC−CO2 and propane extraction technologies to remove oil from rice bran generated in Mississippi. Although the economic analysis
was based on the maximal extraction efficiency for each technology, neither process resulted in a positive rate of return
on investment. 相似文献
14.
《分离科学与技术》2012,47(11):1647-1657
Pressurized liquid extraction was used to obtain beta-ecdysone-rich extracts from Brazilian ginseng (Pfaffia glomerata) roots. The effects of temperature, pressure, and solvent on extraction yield, beta-ecdysone content, and antioxidant activity were determined. Extraction yield increased with temperature up to 25% (dry basis) while the selectivity decreased. The use of Ethanol:Water (80:20 v/v) as solvent produced extracts with the highest antioxidant activity. Beta-ecdysone recovery was maximized using pure ethanol. In the first hour of extraction, approximately 70% of the total yield and 74% of the total beta-ecdysone mass is obtained. The cost of manufacturing significantly decrease as the extractor capacity increased. 相似文献
15.
Supercritical fluids extraction and anti-solvent purification of carotenoids from microalgae and associated bioactivity 总被引:1,自引:0,他引:1
Bing-Chung Liau Fong-Ping Liang Shih-Lan Hsu Chieh-Ming J. Chang 《The Journal of Supercritical Fluids》2010,55(1):169-8
This study investigated co-solvent modified supercritical carbon dioxide extraction of lipids and carotenoids from the microalgal species of Nannochloropsis oculata. Supercritical carbon dioxide (SCCO2) anti-solvent precipitation of carotenoids from the extracts following purification of Zeaxanthin was also examined. Continuous modification by ethanol of supercritical carbon dioxide extractions showed that the addition ratio was important for extraction efficiency of lipids and carotenoids. SCCO2 extraction at 350 bar, 323 K and 16.7 wt% of ethanol addition yielded 239.7 mg of triglycerides and 7.61 mg of carotenoids per gram extract with a total yield of 15.5%. SCCO2 anti-solvent experiments showed that the content of Zeaxanthin in the precipitate was greater than that in the fraction of normal phase column chromatography. The purest Zeaxanthin (93.8%) was then successfully isolated from the purified fraction by using a reverse-phase HPLC column chromatography. Rat macrophages treated by ultra-sonicated water extracts of the SCCO2 defatted algae showed a positive phagocytotic activity. 相似文献
16.
The recovery of additional co-products from the dry-grind process for ethanol could influence the industry greatly, as most
facilities today rely on subsidies and tax incentives to operate. Modification of the process to include the extraction of
oil could add $0.30–0.50 per bushel to the value derived from corn. A process combining solvent extraction with membrane technology
to recover the oil was investigated. To evaluate the feasibility of this process, several nanofiltration membranes were tested
for their stability in ethanol. Each of the membranes was conditioned with a solution of water/ethanol (0–100 vol/vol%) and
the top three were chosen based on their performance with respect to flux and rejection. Beginning at 5 g/L, solutions of
corn oil in ethanol were concentrated to over 100 g/L with the DK (Osmonics-Desal, Minnetonka, MN), TFC-SR1 (Koch Membrane
Systems, Inc., Wilmington, MA) and TFC-SR2 (Koch) membranes. The liquid extract was then similarly concentrated, yielding
a retentate fraction that was highly concentrated with solids in addition to corn oil, such as protein (zein), lecithins,
and other potentially high-value fractions soluble in ethanol. Analysis of the extract retentate showed a significant increase
in oil concentration with an increase in the volume concentration ratio, indicating that pure ethanol extracts from corn may
be successfully concentrated using nanofiltration membranes. 相似文献
17.
Megan E. Hums Robert A. Moreau Michael J. Powell Jonathan L. Hoyt 《Journal of the American Oil Chemists' Society》2018,95(7):845-852
Sorghum has potential as a domestic source of wax for applications in the food and nonfood industries. The waxes extracted from sorghum have similar physical properties to those of Carnauba wax, a common imported commercial wax. This work focused on the extraction, fractionation, and characterization of waxes from sorghum kernels. Extraction was performed by varying the extraction conditions including temperature and solvents (hexane, ethanol, and methanol). A fractionation technique was developed to separate and quantify waxes from nonwaxes. The fractions were then characterized using a reverse‐phase high‐performance liquid chromatography method developed in our laboratory that utilizes an evaporative light‐scattering detector for quantification. The results showed that the average amount of wax extracted from the surface of intact sorghum kernels was about 0.3 wt% using hexane at temperatures between 25 and 120°C and 1000 psi. The yield of wax via hexane extraction increased with temperature and ranged from about 0.06 to 0.39 wt%. Extraction with alcohols resulted in higher yields of extracts, but after fractionation to remove nonwax components, the yield of waxes was reduced by 31% for ethanol and 47% for methanol compared to hexane. 相似文献
18.
Chattip Prommuak Wanchai De-Eknamkul Artiwan Shotipruk 《Separation and Purification Technology》2008,62(2):444-448
Extraction of carotenoids and flavonoids from yellow Thai silk waste was investigated. The total recovery of 0.7 mg carotenoids and 5.1 mg flavonoids/g dry weight was obtained by ethanol extraction. Different methods for extractions of these pigments were carried out using two benign solvents: ethanol and subcritical water (SW) to determine the extraction efficiency of the solvents in various extraction conditions. For extraction of carotenoids, ethanol was suitable as extraction solvent and the amount of carotenoids increased with increasing temperature and extraction time. For flavonoids, SW extraction was suitable but the amount of flavonoids decreased with increasing SW temperature and extraction time due to decomposition at such conditions. In addition, the silk extracts were found to have low IC50 values (15.6–23.3 μg/ml), the concentrations of the silk extracts that exhibit 50% reduction in 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid), (ABTS) free radicals, thus indicating high antioxidant activities. 相似文献
19.
Harrison Lik Nang Lau Yuen May Choo Ah Ngan Ma Cheng Hock Chuah 《Journal of the American Oil Chemists' Society》2006,83(10):893-898
The qualities of oils extracted from fresh and dried palm-pressed mesocarp fiber were evaluated. The means of extraction included
conventional solvent extraction and supercritical carbon dioxide (SC-CO2) extraction with and without addition of ethanol. Extraction efficiency using pure SC-CO2 and the effect of moisture content on efficiency were studied. Minor components, such as vitamin F, carotenoids, squalene
and phytosterols, obtained by different methods were compared. The quality of oil recovered from fresh palm-pressed fiber
is generally better than that of oil recovered from dried fiber. The SC-CO2 extraction rate was lower for fresh fiber than for dried fiber. The incorporation of ethanol with SC-CO2 resulted in oil with higher oxidative stability than did SC-CO2 alone. Concentrations of minor components and the acylglycerol compositions of the oils extracted from both types of fibers
were similar. 相似文献
20.
K. Radha Krishnan P. Azhagu Saravana Babu S. Babuskin M. Sivarajan 《Chemical Engineering Communications》2013,200(12):1577-1585
In the present research work, the effect of solvents, particle size, solvent/solid ratio, and temperature on the extraction efficiency of oregano (Origanum vulgare) and mustard (Brassica nigra) were investigated. The extraction process proceeded at a fast rate followed by a slower one. Particle size, solvent type, solvent/solid ratio and temperature had a positive effect on the extraction process, and maximum extraction was achieved by ethanol. Extraction kinetics was determined with a mathematical model derived from Fick's second law. The results were verified with Fick's diffusion model for extraction kinetics in all experiments, which provided the initial rate and extent of solid–liquid extraction. Antioxidant values were determined using 1, 1-diphenyl-2-picrylhydrazyl (DPPH) and 2, 2′-azino-Bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS). The extracts of O. vulgare and B. nigra prepared using ethanol showed optimal antioxidant activity. 相似文献