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1.
Supercritical CO2 extraction is a viable alternative process for the extraction of high-quality oil from olive husk (also known as olive pomace),
a residue obtained in the production of olive oil. We analyzed the effect of pressure (100–300 bar), temperature (40–60°C),
solvent flow (1–1.5 L/min), and particle size (0.30–0.55 mm) on four important quality parameters of the oil extracted with
CO2: tocopherol concentration, extinction coefficients at 232 and 270 nm, and saponification value. Response surface methodology
was used to obtain mathematical expressions related to the operating variables and parameters studied. Results from these
experiments were also used to design a three-step sequential CO2 extraction procedure to obtain a higher-quality extract. The optimal operational sequence consisted of a first extraction
step at 75 bar for 1 h using 1% (vol/vol) ethanol modifier, followed by a second extraction stage at 350 bar for 2.5 h without
ethanol and a third step, also at 350 bar, for 2.5 h but using ethanol. These extraction conditions obtained an intermediate
fraction of oil with 64% yield and all normal parameters according to European Commission food legislation. This fraction
is suitable without any further refining. On the contrary, the oils obtained by hexane extraction and by conventional supercritical
CO2 extraction at optimal conditions are suitable for human consumption after further refining. This last finding may result
in improved economics of the sequential CO2 extraction process compared to the conventional extraction method with hexane. 相似文献
2.
Lampante olive oil refining with supercritical carbon dioxide 总被引:6,自引:4,他引:6
P. Bondioli C. Mariani A. Lanzani E. Fedeli A. Mossa A. Muller 《Journal of the American Oil Chemists' Society》1992,69(5):477-480
Lampante olive oil has been treated in a supercritical CO2 extraction plant operating in a continuous countercurrent mode. We report the results of a systematic investigation to define
the optimal operative parameters. We also have examined the compositional variation of lampante olive oil samples with different
characteristics and of different geographic origins before and after refining at optimal conditions. Although practical feasibility
of the proposed procedure can be questioned, the results demonstrate the possibility of fractionating components contained
in the starting oil even if present at trace levels. 相似文献
3.
为了回收利用葡萄酒酿造过程产生的副产品中的有效成分,本文利用超临界CO2萃取技术从葡萄籽中提取含有不饱和脂肪酸的葡萄籽油,意在考量超临界CO2技术在萃取葡萄籽油方面的作用。设计单因素实验,研究了萃取压力、萃取温度、CO2流量以及停留时间对葡萄籽油萃取率的影响。单因素实验结果表明萃取压力对萃取结果的影响最为显著。萃取温度和CO2流量对萃取率的影响都存在最佳值,当温度和流量超过最佳值,萃取率开始降低。在单因素实验的基础上进行响应面实验,采用中心复合设计进行实验方案设计以优化萃取葡萄籽油工艺。对响应面实验结果进行方差分析,建立多元回归模型,模型P值<0.0001,预测超临界CO2萃取葡萄籽油的最佳萃取条件为:萃取压力28MPa、萃取温度321 K、CO2流量15.5L/h,停留时间155min,萃取率达到14.12%。 相似文献
4.
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
5.
A. Molero G mez E. Mart nez de la Ossa 《Journal of the American Oil Chemists' Society》2000,77(9):969-974
The extraction of wheat germ oil by liquid and supercritical CO2 is described from the point of view of both operative method and pretreatment of raw material. The best conditions for wheat
germ oil extraction are: pressure, 150 bar; temperature, 40°C; and solvent flow rate, 1.5 L/min at standard temperature and
pressure. The yields and fatty acid compositions obtained are very similar to those resulting from the conventional extraction
process using hexane as solvent (8.0 wt%), although a higher-quality oil is obtained by using CO2 as solvent (free fatty acids, 12.4%; tocopherol content, 416.7 mg tocopherol/g wheat germ oil). These factors lead to the
conclusion that the extraction process using CO2 could be economically competitive with the conventional process, since it considerably simplifies the oil refinement stages
and completely eliminates the solvent distillation stage, which are the most costly processing steps in terms of energy consumption. 相似文献
6.
Ehsan Jenab Karamatollah Rezaei Zahra Emam‐Djomeh 《European Journal of Lipid Science and Technology》2006,108(6):488-492
Samples of crushed and cooked canola seeds (Okapy Double Zero) were extracted using supercritical carbon dioxide (SCCO2) (34.0 MPa and 40.0 °C) and a commercial organic solvent (AW406). Oil solubility was obtained through several stepwise extractions under the conditions of this study, and then three additional extractions were performed to measure fatty acid compositions, iodine values, chlorophyll concentrations and unsaponifiable matter. The yield of SCCO2 extraction was lower than that after extraction with AW406 solvent, due to the incomplete SCCO2 extraction process. Fatty acid composition analysis showed that the SCCO2‐extracted oil was slightly higher in polyunsaturated fatty acids and lower in erucic and behenic acids. However, iodine values and unsaponifiable matter did not indicate significant differences (p >0.05) in the two extracted oils. The chlorophyll concentration of SCCO2‐extracted oil was lower than that in the AW406 solvent, and as a result, the color of SCCO2‐extracted oil was lighter. 相似文献
7.
Supercritical carbon dioxide (SC-CO2) was used to partially defat walnuts, and the oxidative stability of the extracted walnut oils was assessed. The SC-CO2-extracted oils were less stable during accelerated storage in the dark than was pressed walnut oil, as determined by PV,
headspace analysis by solid-phase microextraction, and sensory methods. The SC-CO2-extracted oils, however, exhibited greater photo-oxidative stability than did pressed walnut oil by all of these methods,
possibly because of the presence of chlorophyll in the pressed oil. Oxidative stability indices and tocopherol contents were
significantly lower in the SC-CO2-extracted oils than in pressed oil. 相似文献
8.
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
9.
10.
响应曲面法优化超临界CO2萃取猕猴桃籽油条件 总被引:2,自引:0,他引:2
以猕猴桃籽为试验原料,在单因素试验的基础上,采用响应曲面分析法建立了超临界CO2萃取猕猴桃籽油萃取率的二次多元回归方程,探讨了压力、温度、CO2流量等关键因素对萃取率的作用规律。结果表明,萃取压力、温度、CO2流量对萃取率影响显著,萃取压力和温度交互效应影响显著。根据萃取率回归方程对猕猴桃籽油的超临界萃取工艺参数进行了优选,最优工艺参数为:压力31.7 MPa,温度40.2℃,CO2流量27.4 kg/h,该条件下萃取率高达32.57%,与试验值31.24%仅有4.5%的误差,证实了该方程的预测值与试验值之间具有较好的拟合度。超临界CO2萃取的猕猴桃籽油与己烷提取的油脂在脂肪酸组成上没有显著差别。 相似文献
11.
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
12.
13.
14.
Influence of ecological cultivation on virgin olive oil quality 总被引:1,自引:1,他引:0
Francisca Gutiérrez Teresa Arnaud Miguel A. Albi 《Journal of the American Oil Chemists' Society》1999,76(5):617-621
The quality of oil extracted from ecologically cultivated olives of the Picual variety was compared with oil extracted from
Picual olives cultivated using conventional methods. Olive trees were grown in a two-section plot. Fruits from each plot were
harvested at various stages of ripeness, and acidity value, peroxide index, ultraviolet absorption at 232 and 270 nm, stability
to oxidation, sensory analysis, fatty composition, and contents of tocopherols, phenolic compounds, and sterols were determined
on oil extracted from each treatment. The results showed that the organic virgin olive oil was of a superior quality to the
conventional virgin olive oil in all the quality parameters analyzed. 相似文献
15.
Enzymatic alcoholysis of cod liver oil, with an immobilized lipase, was carried out in supercritical carbon dioxide. The enzyme
was catalytically active under the experimental conditions used. The reaction medium was investigated to preferentially extract
ethyl esters, synthesized during the course of the experiment, from the unconverted cod liver oil substrate and side-products.
The effect of pressure changes on the amount of tri-, di-, and monoglycerides and ethyl esters, present in both the extract
and the remaining lipid residue, was determined. Furthermore, the fatty acid compositions of the lipid classes were analyzed,
and the relative amounts of both eicosapentaenoic acid and docosahexaenoic acid to palmitic acid were determined. The results
show that it is possible to preferentially extract the synthesized ethyl esters at low pressures. The extract collected at
9 MPa contained 64 g ethyl esters/100 g extract, while the total amount of all other lipid classes detected was 19 g/100 g
extract. As the pressure was increased, the relative amount of the other lipid classes detected in the extract, especially
triglycerides, was enhanced. The relative amounts of both eicosapentaenoic acid and docosahexaenoic acid to palmitic acid
increased for some lipid classes in the extract. This increase was most pronounced for the monoglyceride lipid class. The
integration of biocatalysis and product fractionation, applied in this study, suggests that the potential for biocatalysis
in industrial processes is considerably wider than had been thought. 相似文献
16.
藿香不仅是一种中草药,还是一种天然香料植物,可从中提取藿香浸膏和藿香油,用来调配香精,用于日用品和食品的加香。本文通过单因素试验和正交试验,对超临界二氧化碳提取藿香梗和藿香叶浸膏的提取工艺条件进行了优化。超临界二氧化碳萃取藿香梗浸膏的最佳工艺条件是萃取压力15 MPa、萃取温度42 ℃、CO2流量37 L8226;h-1、萃取时间3.5 h,产率为1.28%;超临界二氧化碳萃取藿香叶浸膏的最佳工艺条件是萃取压力18 MPa、萃取温度39 ℃、CO2流量37 L8226;h-1、萃取时间3.5 h,产率为2.53%。 相似文献
17.
L. Calvo M. J. Cocero J. M. Díez 《Journal of the American Oil Chemists' Society》1994,71(11):1251-1254
Extraction of oilseeds with supercritical carbon dioxide (SC−CO2) is a promising technique to obtain vegetable oils. However, instability of such oils has been associated in the past with
SC−CO2 extraction. The reasons underlying such instability were unclear. Results presented here suggest that oil instability may
be related to the oxygen content of CO2. In fact, oil stability decreases sharply when refined oil (additive-free) is re-extracted with SC−CO2 and can be related to the oxygen content in the CO2. Never-theless, oil stability could be improved to the level of conventionally extracted oil by adding trace amounts of ascorbic
acid. 相似文献
18.
Stoning olives has been proposed as an alternative to crushing the whole fruit during the oil extraction process. Seven pairs
of oils obtained from stoned and nonstoned olives from five different cultivars were evaluated to determine the effect of
the proposed technology on oil quality. The main organoleptic and physicochemical parameters as well as resistance to oxidation
showed no obvious influence of stoning on oil quality. Chemometric analysis of the data showed the oils grouped more according
to genetics (cultivar) than to technology. Lipoxygenase activity in the paste from whole and stoned olives showed no effect
that could be attributed to the technology. Furthermore, the stone did not contribute significantly to increasing the lipoxygenase
activity in the olive paste. 相似文献
19.
Extraction of essential oil from geranium (Pelargonium graveolens) with supercritical carbon dioxide
Amelia Peterson Siti Machmudah Bhupesh C Roy Motonobu Goto Mitsuru Sasaki Tsutomu Hirose 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(2):167-172
This study investigated the supercritical fluid extraction (SFE) of geranium essential oil from geranium (Pelargonium graveolens) using supercritical carbon dioxide solvent. The extraction yield was measured as a function of pressure, temperature and carbon dioxide flow rate. At low pressure (10 MPa) and high temperature (343 K), waxes were co‐extracted with the essential oil, resulting in artificially elevated essential oil extraction yields as no method was available with the SFE apparatus used to separate co‐extracted waxes and oil. At high pressure (30 MPa) and low temperature (313 K), the amount of wax co‐extracted decreased. Under these ‘optimum’ conditions, the extraction yield increased with decrease in flow rate giving a maximum extraction yield of 2.53%. All samples were analyzed by gas chromatography–mass spectrometry and the effect of pressure and extraction time on oil composition was studied. The percentage compositions of terpene hydrocarbons, terpenols, geraniol and geranyl esters were significantly affected by pressure and extraction time. The oil samples obtained by SFE were also compared with commercially obtained steam distilled samples. All major components of the commercially obtained oils were present in the SFE‐obtained oils; however, the percentage composition of the major components differed greatly between steam distilled and SFE oils. Copyright © 2005 Society of Chemical Industry 相似文献
20.
Helga Gunnlaugsdottir Björn Sivik 《Journal of the American Oil Chemists' Society》1997,74(11):1483-1490
A combined process of lipase (E.C. 3.1.1.3) catalysis and extraction of product with supercritical carbon dioxide was studied.
The effect of different flow rates of the extraction fluid on the selective removal of the ethyl esters (EE) synthesized in
a lipase-catalyzed alcoholysis of cod liver oil with ethanol was investigated. The faster the flow rate, the faster the extraction
rate and the higher the recovery of EE. For example, after a 270-min extraction, the total recovery of EE was 1520 mg for
a flow rate of 0.3 liter carbon dioxide at atmospheric pressure and room temperature/min (NL/min) as compared to 250 mg when
0.015 NL/min was used. The concentration of EE in the carbon dioxide was found to decrease with increasing flow rate, which
indicates that the rate of diffusion of EE limits their extraction at fast flow rates. A high flow rate was found to result
in a more selective extraction of EE, i.e., less amounts of other lipid components present in the reaction mixture were coextracted
with the EE. Further, by increasing the flow rate, the equilibrium of the reaction was shifted slightly toward ester synthesis.
An increase in the flow rate from 0.015 to 0.075 NL/min resulted in an approximately 10% increase in total conversion (from
73 to 82%), whereas only a negligible increase was obtained when the flow rate was increased further to 0.15 NL/min. 相似文献