Extraction of canola seed (Brassica napus) oil using compressed propane and supercritical carbon dioxide

This study aimed to investigate the extraction of canola seed (Brassica napus) oil using supercritical carbon dioxide and compressed propane as solvents. The extractions were performed in a laboratory scale unit at temperatures and pressures of 40, 50 and 60 °C and 20, 22.5 and 25 MPa for carbon dioxide and 30, 45 and 60 °C and 8, 10 and 12 MPa for propane extractions, respectively. The results indicated that pressure and temperature were important variables for the CO₂ extraction, while temperature is the most important variable for the extraction yield with propane. The extraction with propane was much faster than that with carbon dioxide. The characteristics of the extracted oil, that is, the oxidative stability determined by DSC and the chemical profile of fatty acids determined by gas chromatography, were similar for the two solvents. The overall extraction curves were well described by the Sovová model.     

超临界二氧化碳萃取和精制柚皮香精油的研究

通过单因素和正交实验研究了超临界CO2 萃取柚皮精油的最佳工艺条件为 :原料粒度 60目 ,萃取时间 1h ,流量 2 0kg/h ,温度40℃ ,压力 16MPa。对柚皮精油采用二级分离脱萜的适宜的工艺条件为 :分离器Ⅰ压力 9MPa ,温度 45℃ ;分离器Ⅱ的压力 5MPa ,温度 50℃。分离器Ⅰ精油得率为 1 3 2 % ,比旋光度为αD2 0 3 9°72′。     

Optimization of supercritical carbon dioxide extraction of sea buckthorn (Hippophaë thamnoides L.) oil using response surface methodology

Response surface methodology (RSM) was employed to optimize the conditions of supercritical CO₂ extraction of the whole berry oil from sea buckthorn. The effects of pressure, temperature, CO₂ flow rate and extraction time on the yield of oil, vitamin E and carotenoids were investigated. Results showed that the data were adequately fitted into three second-order polynomial models. The independent variables, the quadratics of pressure and extraction time, the interactions between pressure and temperature, pressure and extraction time, temperature and extraction time, as well as flow rate and extraction time had a significant effect on the yield of the oil, vitamin E or carotenoids. It was predicted that the optimum extraction conditions within the experimental ranges would be the extraction pressure of 27.6 MPa and temperature of 34.5 °C with flow rate of 17.0 L/h and extraction time of 82.0 min. Under such parameters, the yields of oil, vitamin E and carotenoids were predicted to be 208.0 g/kg, 288.7 mg/kg and 620.0 mg/kg dry sea buckthorn berry, respectively. Monounsaturated fatty acids were predominant in the whole berry oil, accounting for over 62% of the total fatty acids.     

超临界二氧化碳萃取玫瑰茄籽油的响应面优化

在单因素实验基础上,以萃取温度、萃取压力、萃取时间为影响因素,以萃取率为指标,运用响应面实验设计法对超临界CO2萃取玫瑰茄籽油工艺条件进行优化。结果表明,在萃取温度50℃、萃取压力28MPa、萃取时间110min的条件下,玫瑰茄籽油提取率可达22%以上。     

超临界CO_2萃取黑加仑籽油研究

利用超临界CO2萃取技术,对影响黑加仑油萃取工艺条件进行研究,得出最佳工艺条件:投料量300g、萃取温度30℃、萃取压力25MPa,粉碎度50目、萃取时间3.5h;在此条件下黑加仑提油率为90.78%。超临界CO2法得到黑加仑籽油不饱和脂肪酸含量达90%以上,其中γ-亚麻酸含量为15.2%,品质优于溶剂萃取。     

Supercritical CO2 extraction of trans-lycopene from Portuguese tomato industrial waste

Supercritical CO₂ extraction of trans-lycopene from Portuguese tomato industrial wastes (skins and seeds) was carried out in a flow apparatus. The effects of moisture content, feed initial composition, particle size, solvent flow-rate, pressure and temperature on the extraction yield and recovery were evaluated.     

超临界二氧化碳萃取石榴籽油的研究

利用超临界CO2对石榴籽中石榴籽油的萃取进行了研究,研究了粉碎度、装料量、萃取压力、萃取温度、CO2流量、分离压力和分离温度对石榴籽油萃取率的影响。试验表明,超临界CO2萃取石榴籽油的工艺参数是粉碎度40目、装料量200g、萃取压力30MPa、萃取温度40℃、CO2流量15L/h、分离压力8MPa、分离温度35℃,萃取率23.55%。     

Effects of supercritical carbon dioxide extraction parameters on virgin coconut oil yield and medium-chain triglyceride content

The extraction of coconut oil has been performed using supercritical carbon dioxide (SC-CO₂). The extractions were performed at pressure and temperature ranges of 20.7–34.5 MPa and 40–80 °C, respectively. It was observed that almost all (more than 99%) of the total oil could be extracted. Response surface methodology (RSM) was applied to evaluate the effects of the parameters (pressure, temperature and CO₂ consumption) on the extraction yield and medium-chain triglycerides (MCTs), in terms of the fatty acid content in the extracted oil. A correlation was established with p-values for both responses significant at the 95% confidence level.     

山茶油的超临界CO_2逆流萃取脱酸脱臭研究

研究新的山茶油脱酸脱臭方法。采用超临界CO2逆流萃取对山茶毛油进行脱酸脱臭处理。结果显示,最佳的脱酸脱臭工艺条件为:进料位置为萃取柱Ⅳ段底部,萃取压力18.5 MPa,萃取柱Ⅰ、Ⅱ、Ⅲ、Ⅳ段温度分别为35、50、65、80℃,CO2流速15 L/h,分离釜压力5 MPa,分离釜温度40℃。通过1次逆流萃取,山茶油的酸值降低28.96%,臭味显著降低。山茶油的超临界CO2逆流萃取脱酸脱臭效果显著,工艺简单,并能保护其活性成分不被破坏,保持山茶油的天然品质。     

Concentration of tocopherols by supercritical carbon dioxide with cosolvents

In order to optimize the conditions for enrichment of tocopherols, tocopherol extraction from chemically modified rapeseed deodorizer distillate (RDD) at three levels (2%, 4%, and 6%) of each cosolvent (methanol, ethanol, and mixed ethanol) was carried out by using supercritical carbon dioxide (SC-CO₂). After chemical modification, the fatty acid methyl esters (FAME) in RDD were produced and showed improved solubility in SC-CO₂. Since FAME were more volatile, they were extracted preferentially over tocopherols and other higher molecular weight compounds. Two steps were applied in the SC-CO₂ extraction. First, the FAME mixture was extracted under 120 bar until the weight of extracts did not increase anymore, and then, tocopherols were concentrated under 250 bar. Second, the concentrates from the first step under 250 bar were esterified and then extracted again under 120 bar until the weight of extracts did not increase anymore. Different cosolvents (methanol, ethanol, mixed ethanol) were used for tocopherol isolation under 250 bar in the second step. Tocopherol content, tocopherol recovery and the weight of target extract (those extracts with a concentration of tocopherols above 40%) increased while the extraction time decreased.     

Improved lycopene extraction from tomato peels using cell-wall degrading enzymes

Four commercial enzyme preparations with pectinolytic, cellulolytic and hemicellulolytic activities were tested for their ability to enhance lycopene extraction from tomato peels. Screening experiments were performed at 25 °C by subjecting the peels to a 4-h enzyme incubation followed by 1-h hexane extraction. Peclyve EP and LI were the most efficient, with an almost 20-fold increase in extraction yield. Peclyve LI was used to evaluate the influence of solvent type and enzyme incubation time on lycopene recovery. Hexane, ethyl acetate and the mixture hexane/acetone/ethanol 50:25:25 (v/v) were used as solvents. Under the best extraction conditions (1-h enzyme incubation followed by a 3-h solvent extraction at 40 °C) up to 440 mg of lycopene per 100 g of dry tomato peels were obtained. The percentage recoveries were in the range of 3–30%, for the untreated peels, and 77–98% for the enzymatically treated material.     

In vitro antioxidant activities of Rosmarinus officinalis extracts treated with supercritical carbon dioxide

The leaves of Rosmarinus officinalis (rosemary) were subjected to supercritical CO₂ extraction (SFE). Different sources of variability, including location (Izmir, Canakkale and Mersin) and harvesting time (December, March, June and September), were considered. Among active constituents of rosemary, carnosic acid, carnosol and rosmarinic acid were analyzed by HPLC. Variability of the amounts of active constituents appears to be due to different geographical locations of growth and seasonal variations. The levels of the constituents were higher in the months of December 2003 and September 2004. In addition to this, 12 SFE extracts were screened for their radical-scavenging capacities and antioxidant activities by various in vitro assays, namely total phenol assay, DPPH radical-scavenging activity and trolox equivalent antioxidant capacity (TEAC).     

A supercritical tuneable process for the selective extraction of fats and essential oil from coriander seeds

A selective supercritical CO₂ extraction process has been developed in order to extract selectively the vegetal oil and the essential oil from coriander seeds in a consecutive way by tuning experimental conditions. A 4-step process has been set up: (i) seeds preparation by grinding and sieving, (ii) extraction by supercritical CO₂ and (iii; iv) selective separation in two separators with different pressure levels. The first part of this study consisted in studying the effects of the operating conditions (T, P, CO₂ density, flow rate and particle size distribution of ground seeds) on the yield of extraction. The results showed that the global performance of the process depends mainly on the pressure level of extraction, on the CO₂ flow rate and on the size of the ground seeds. An optimization of the parameters led to an extraction ratio of 90%. The second part of this study dealt with the effects of the operating conditions on the quality of extracts, and more precisely on their composition in vegetal oil and essential oil. It was observed that the supercritical extraction had no major effect on the fatty acid composition of the vegetal oil compared to classical extraction techniques, while essential oil is enriched in components such as linalool and that a previous drying of the seeds is deleterious. Finally, we propose a procedure in order to extract separately each oil by adjusting CO₂ density and separation conditions.     

Supercritical CO2 extraction optimization of pomegranate (Punica granatum L.) seed oil using response surface methodology

This study examined extraction of pomegranate seed oil by using supercritical carbon dioxide. Response surface methodology was used to evaluate the effects of the process parameters, namely extraction pressure, temperature and CO₂ flow rate on the yield of pomegranate seed oil. The extraction parameters were optimized with a central composite design experiment. The linear term of pressure, followed by the linear term of CO₂ flow rate, the quadratic terms of pressure, temperature and CO₂ flow rate and the interactions between pressure and temperature, as well as CO₂ flow rate and temperature, had significant effects on the oil yield (p < 0.05). Maximum yield of pomegranate seed oil from the mathematical model was predicted to be 156.3 g/kg dry basis under the condition of pressure 37.9 MPa and temperature 47.0 °C with CO₂ flow rate of 21.3 L/h. The fatty acid composition and the tocopherols' content of pomegranate seed oil extracted using supercritical CO₂ were compared with those obtained by Soxhlet method. Minor difference was found in the fatty acid composition of the oils extracted by the two methods. The content of total tocopherols was about 14% higher in the oil extracted with supercritical CO₂ than that obtained by Soxhlet extraction.     

Enrichment of tocopherols in modified soy deodorizer distillate using supercritical carbon dioxide extraction

Supercritical carbon dioxide (SC-CO₂) extraction of chemically modified Soy Deodorizer Distillate (DOD) at three levels of pressure (180–300 bar) and temperature (40–60 °C) to optimize the conditions for enrichment of tocopherols in the raffinate was carried out. After modification, soy DOD contained about 90% of fatty acid methyl esters (FAME), showed improved solubility in SC-CO₂, and better extraction rate. Since fatty acid methyl esters are more volatile, they are extracted preferentially over tocopherols and other high molecular weight compounds. Higher levels of pressure and temperature resulted in increased solubility of compounds with high molecular weight and tocopherols due to increased density of SC CO₂. So the extraction at higher pressures and temperatures resulted in a better yield of FAME along with tocopherols in the extract and this in turn decreased the degree of enrichment of tocopherols in the raffinate. However, specific level of pressure and temperature of extraction caused the increase in the solubility of FAME due to their volatility and results in enhanced enrichment of tocopherols in the raffinate. It was observed that the enrichment of tocopherols to ten times the original concentration of feed occurred at extraction pressure of 180 bar and temperature of 60 °C of SC-CO₂.     

Pressing and supercritical carbon dioxide extraction of walnut oil

The objective of this study was to evaluate the oil extraction process from walnut seeds by pressing followed by extraction with supercritical CO₂. In pressing experiments, a factorial arrangement was conducted in order to study the combined effects of seed moisture content (2.5%, 4.5% and 7.5%) and pressing temperature (25, 50 and 70 °C) on oil recovery and quality parameters. For all conditions tested, the oil quality compared well with that of cold-pressed walnut oil. Oil recovery increased significantly as moisture content raised. Highest oil recovery (89.3%) was obtained at 7.5% moisture content and 50 °C temperature. The cake resulting from pressing at these conditions was extracted with CO₂ in a high pressure pilot plant with single stage separation and solvent recycle. The effects of two different pressures (200 and 400 bar) and temperatures (50 and 70 °C) with regard to oil yield and quality, and time required for extraction were analyzed. At each condition, the extraction rate changed with the mass of solvent and extraction time. At first, the mass of oil extracted was determined by the oil solubility in CO₂ and a linear relationship was observed, where the slope results in the solubility of oil in CO₂ at the experiment conditions. After that, the extraction rate was governed by solubility and diffusion, and continuously decreased with time. The colour changed along the extraction from a whitish clear product to a yellow one. Tocopherol and carotenoid contents were significantly higher than those obtained by pressing. Extraction conditions did not affect significantly the fatty acid composition.     

Extraction of lipids from cherry seed oil using supercritical carbon dioxide

 Cherry seeds (Prunus avium L.) were extracted with compressed carbon dioxide at 313 K and 333 K in the pressure range 18–22 MPa. The influence of superficial velocity was also analysed using values of 0.02, 0.06 and 0.08 cm/s. The extraction yield was increased by a reduction in particle size. The physical and chemical characteristics of the oil were determined. The results, in terms of free fatty acids and sterol compositions, were compared with those obtained when hexane was used as solvent. Other physical and chemical characteristics were also compared with refined hexane-extracted oil. Received: 29 February 2000 / Revised version: 19 April 2999     

超临界CO2结合夹带剂萃取紫苏籽油研究

选择无水乙醇和乙酸乙酯作为夹带剂,超临界CO2萃取紫苏籽油.以得油率为考察指标,采用正交试验优化萃取条件,获得紫苏籽油萃取的最优工艺条件为:夹带剂为乙酸乙酯,添加量为CO2摩尔流量的3％,萃取温度40℃,萃取压力25 MPa.在此条件下,紫苏籽油得油率为36.7％.对萃取所得紫苏籽油品质进行测定,结果显示除了酸值偏高以外,其他指标均在正常范围内.紫苏籽油脂肪酸组成分析显示,不饱和脂肪酸含量丰富,尤以α-亚麻酸的含量最高,占总脂肪酸含量的61.45％.     

超临界CO_2流体萃取石榴籽油工艺条件的研究

以石榴籽为原料,对超临界CO2流体萃取石榴籽油的工艺条件进行了研究。通过单因素试验,研究了萃取压力、萃取温度和萃取时间对石榴籽油得率的影响。在单因素试验的基础上,通过正交试验确定了超临界CO2流体萃取石榴籽油的最佳工艺条件。结果表明,超临界CO2流体萃取石榴籽油最佳工艺条件为:萃取压力40 MPa,萃取温度55℃,萃取时间80 min,分离釜Ⅰ温度60℃,压力10 MPa,分离釜Ⅱ温度35℃,压力6 MPa。在最佳工艺条件下,石榴籽油得率为18.6%。     

响应面优化超临界CO2萃取怀远石榴籽油及其体外抗氧化性研究

以怀远石榴籽为原料,采用超临界CO_2萃取法制得石榴籽油。在单因素实验的基础上,以萃取压力、萃取温度、萃取时间及粉碎度为自变量,石榴籽油得率为响应值,采用响应面法优化萃取工艺,并对石榴籽油的理化指标与体外抗氧化性进行测定和分析。结果表明:超临界CO_2萃取石榴籽油的最佳萃取工艺条件为萃取压力32.0 MPa、萃取温度50.0℃、萃取时间103.0 min、粉碎度60.0目,在此条件下怀远石榴籽油得率为19.4%;超临界CO_2萃取法得到的石榴籽油酸值低,过氧化值与皂化值小,对DPPH·、ABTS~+·以及O_2~-·等自由基的清除能力较强。