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SYED S. H. RIZVI ZER-RAN YU AJAY BHASKAR LORRAINE ROSENBERRY 《Journal of food science》1993,58(5):996-1000
A static method was used to measure the solubilities and distribution coefficients of δ-lactones (pure), inherent (natural levels) δ-lactones of anhydrous milk fat (AMF) and fortified (added) δ-lactones in AMF in supercritical carbon dioxide (SC-CO2) at 40°C with pressures of 5–30 MPa. At 40°C distribution coefficients of δ-lactones increased with pressure and exhibited molecular weight-dependency. Using experimental data, a mathematical model based on thermodynamic equilibria and material balance was developed and used to predict the distribution of inherent δ-lactones of AMF in a continuous SC-CO2 extraction system. At 24.1 MPa/40°C column conditions, AMF was separated into a raffinate and 5 fractions. Predicted δ-lactones distribution coefficients in the raffinate and extract were in good agreement with experimental data. 相似文献
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A continuous supercritical carbon dioxide processing system was designed, built and operated to investigate its performance for fractionation of anhydrous milk fat (AMF). Packed columns showed mass transfer efficiencies five times greater than a spray column, Short- and medium-chain fatty acids were concentrated in the extract fractions and their amounts decreased as separation pressure increased. The ratio of unsaturated to saturated fatty acids in the raffinate fraction was 0.68 compared to 0.52 in the original AMF. The proportions of low-melting triglycerides in the range —42 to 15°C were greater in the extract fractions (44–72%) compared to the original AMF (29%). 相似文献
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Utilization of beef fat might be improved via production of fractions with specific functional properties. Beef fat was fractionated using supercritical carbon dioxide at 40°C and pressures from 10.3–27.6 MPa. Extractions followed by one or two stage separation were collected into glass vials at atmospheric pressure and temperature. Resultant extracts were analyzed for fatty acid content by gas chromatography (GC). A significant difference in concentration due to extraction pressure for 16 straight chain fatty acids, 6 branched chain fatty acids, and 7 unknowns was found. Total fatty acids (mg/g extract) increased as pressure increased. Monounsaturated and polyunsaturated fatty acids increased with increasing pressure and solvent density as shown by the saturate/ unsaturate, saturate/monounsaturate, and saturate/polyunsaturate ratios. 相似文献
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Sudarsan Mukhopadhyay Devanand L Luthria Rebecca J Robbins 《Journal of the science of food and agriculture》2006,86(1):156-162
An investigation to optimize the extraction of phenolic acids from black cohosh using a pressurized liquid extractor system was studied with the aim of developing a generalized approach for sample preparation of phenolic compounds from plant matrices. Operating parameters such as solvent composition, solid‐to‐solvent ratio, temperature, particle size distribution, and number of extraction cycles were identified as main variables that influence extraction efficiency. A mixture of methanol and water (60:40 v/v) was found to be the best solvent for total phenolics (TP) and individual phenolic acids. The four phenolic acids extracted from black cohosh were identified by HPLC and LC‐MS as caffeic acid, ferulic acid, sinapic acid and isoferulic acid. Over 96% of the measured phenolics were extracted in first two cycles. The extraction efficiency for black cohosh with MeOH:H2O (60:40 v/v) was found to be maximum at a solid‐to‐solvent ratio of 80 mg ml?1. TP content of the extract was found to increase with temperature up to 90 °C. Particle size was found to have a large impact on extraction efficiency of TP. Samples with particle size between 0.25 mm and 0.425 mm provided optimum extraction of phenolics from black cohosh. Published in 2005 for SCI by John Wiley & Sons, Ltd. 相似文献
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Sage herb (Salvia officinalis L.) was extracted at supercritical fluid extraction (SFE) conditions with carbon dioxide at different parameters and the extracts tested on their antioxidant activity (AA). SFE of sage herb at 35 MPa pressure was found to be an effective method to obtain pure extracts. The yields of the extracts were substantially increased by using 1% of entrainer solvent ethanol. The fractionation of sage extract was a complex procedure in terms of extract distribution between separators operating at various pressure and temperature conditions. It was also proved by testing the AA of the extracts in rapeseed oil. The effect of the extracts on the rapeseed oil weight gain varied in a wide range (from 'very low' to 'high') depending on the fractionation conditions. Preliminary results showed that to obtain more effective antioxidant fractions separation steps should be started at 10 MPa lower pressure than that used for the extraction. 相似文献
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E. Daukas P. R. Venskutonis V. Povilaityte B. Sivik 《Molecular nutrition & food research》2001,45(5):338-341
Sage herb (Salvia officinalis L.) was extracted at supercritical fluid extraction (SFE) conditions with carbon dioxide at different parameters and the extracts tested on their antioxidant activity (AA). SFE of sage herb at 35 MPa pressure was found to be an effective method to obtain pure extracts. The yields of the extracts were substantially increased by using 1% of entrainer solvent ethanol. The fractionation of sage extract was a complex procedure in terms of extract distribution between separators operating at various pressure and temperature conditions. It was also proved by testing the AA of the extracts in rapeseed oil. The effect of the extracts on the rapeseed oil weight gain varied in a wide range (from ‘very low’ to ‘high’) depending on the fractionation conditions. Preliminary results showed that to obtain more effective antioxidant fractions separation steps should be started at 10 MPa lower pressure than that used for the extraction. 相似文献
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采用有机溶剂萃取法对香荚兰浸膏进行精制,通过电子鼻、感官评定确定最佳溶剂,以主要化合物含量为指标优化溶剂比例及萃取次数,利用气相色谱-质谱法检测浸膏精制前后挥发性成分相对含量。结果表明:最佳溶剂为乙酸乙酯-正丁醇、溶剂体积比3∶7、萃取3次时香草醛相对含量最高为9.48%,香荚兰浸膏精制效果较好;浸膏精制后,芳香族类化合物相对含量由35.58%增加至51.00%,烷烃类化合物相对含量由4.42%减少至0.78%。该研究结果可为香荚兰浸膏综合利用及产品研发提供理论参考及技术支持。 相似文献
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Mangosteen fruit pericarp is one of the important sources of bioactive compound xanthone. Supercritical carbon dioxide (SC-CO2) extraction was employed to extract xanthones from mangosteen fruit pericarp at three different levels of pressure (200–300 bar),
temperature (40–60 °C) and solvent to material ratio (100–300 kg/kg). The optimal conditions for the total xanthone yield
and the influence of parameters were determined by response surface methodology (RSM) using Box–Behnken design. In our study,
the increase in total xanthone yield in SC-CO2 fluid extraction depends more on the solute’s vapor effect. From response surface plots, pressure, temperature and solvent
to material ratio exhibited independent and interactive effects on the extraction of xanthones. A regression equation for
predicting the total xanthone yield was derived by statistical analysis, and a model with predictive ability of 0.99 was obtained.
Maximum xanthone yield of 8.01% was predicted by RSM at 60 °C, 300 bar and a solvent to material ratio of 300 kg/kg while
experimentally a yield of 7.56% was achieved. HPLC analysis was carried out for the optimum conditions for the identification
and quantification of the xanthones. The antioxidant activities of the extracts were investigated by ferric reducing antioxidant
power (FRAP) and the results showed that the extracts were enriched with antioxidant compound. 相似文献
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Lucia Leo Leonardo Rescio Loredana Ciurlia Giuseppe Zacheo 《Journal of the science of food and agriculture》2005,85(13):2167-2174
The objective of this study was to extract oil and tocopherols from almond seeds using supercritical carbon dioxide and to compare this extraction with a traditional solvent method. Oil and tocopherol extraction rates were determined as functions of the pressure (350–550 bar), temperature (35–50 °C) and CO2 flow rate (10–30 kg h−1), using a 10‐l vessel. The effects of matrix particle size on extraction yield were also studied and it was demonstrated that extraction yield is greatly influenced by particle size. Maximum recovery was obtained in the first 2–3 h of extraction at a pressure of 420 bar, a temperature of 50 °C and a flow rate of 30 kg h−1 CO2. These results suggest that the elevated initial oil and tochopherol solubility is related to the increased proportion of fatty acids in the initial extract. The results were compared with those obtained when hexane/methanol was used as a solvent. Copyright © 2005 Society of Chemical Industry 相似文献
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目的:优化葛缕子精油的提取工艺并对其成分进行分析。方法:以葛缕子籽粒为原料,采用超临界CO2技术提取葛缕子精油,并通过气相色谱—质谱(GC-MS)对精油挥发性成分进行分析。结果:超临界CO2提取葛缕子精油的最佳工艺条件为提取釜温度50℃,分离釜温度40℃,提取釜压力30 MPa,分离釜压力0.4 MPa,二氧化碳流速20 g/min,提取时间90 min,此条件下精油得率为4.79%。与同时蒸馏萃取(SDE)法相比,超临界CO2流体能快速扩散到样品颗粒内部并充分溶解其中的精油成分,具有提取时间短、得率高、无溶剂残留的优点。超临界CO2法制备的葛缕子精油中,主要成分为D-柠檬烯(50.96%)和香芹酮(46.65%),挥发性成分种类及含量均高于同时蒸馏萃取法的。结论:超临界CO2法比同时蒸馏萃取法更适合葛缕子精油的提取。 相似文献
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Oil was extracted from fried chipped potatoes using supercritical carbon dioxide. The goals of the study were to determine the effect of process parameters on the extraction, explore the scalability of the process, and determine useful kinetic parameters. Extraction conditions range 27.6–41.4 MPa (4000–6000 PSI), 35–80 °C and solvent flow rate of 0.5–5.0 g CO2/min. Up to 100% of the oil was recovered from the potato chips at the highest pressure and temperature conditions. Two process conditions were chosen for comparison of performance with a larger scale (1:5) system, maintaining the same CO2 flow rate to feed mass ratio. Good agreement between scales was seen at the higher pressure and temperature settings. Kinetic parameters, calculated using a literature model, indicated that, as expected, the extraction is limited by internal diffusion. 相似文献
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Ultrafiltration/Reverse Osmosis Concentration of Lobster Extract 总被引:1,自引:0,他引:1
A membrane concentration system consisting of tubular polysulphone ultrafiltration (UF) and polyamide reverse osmosis (RO) was evaluated for concentrating key water soluble flavor compounds from lobster extracts. Major flavor-giving compounds in the extract were glutamic acid, glycine, arginine, uridine 5′-monophosphate (UMP), succninic acid and glucose. Factors affecting performance of the UF/RO systems, such as flow rate, feed solid level, temperature and pressure, on permeate flux and solids rejection were measured. The optimum UF conditions were 1.5% feed solid level, 15 L/min feed flow rate, 50°C feed temperature and 1 MPa log mean transmembrane pressure. The RO system retained all dissolved flavor components and its ideal operating conditions were 40°C, 2.8 MPa log mean transmembrane pressure and a flow rate of 15 L/min. 相似文献
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目的:研究富贵菜多糖提取纯化工艺,为有效开发利用功能性食品--富贵菜提供方法学基础。方法:通过正交试验,优化提取方案;采用Sevag 法脱蛋白,双氧水和活性碳脱色,蒽酮- 硫酸法测定多糖含量。结果:在温度100℃,固液比1:7(富贵菜:水,g/mL),提取时间3.5h,提取次数2 次的条件下,所得多糖含量最高。以氯仿:正丁醇的体积比4:1 为脱蛋白剂,加入0.15g/mL 的活性炭溶液,80℃脱色45min,脱色2 次或加入多糖供试液体积70% 的双氧水试液于60℃脱色120min 效果最佳。结论:该工艺条件简单可行,多糖提取率高,稳定性好,可作为富贵菜多糖的提取纯化工艺。 相似文献
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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. 相似文献
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《International Dairy Journal》2007,17(9):1021-1027
Three dairy emulsions containing 10 wt% anhydrous milk fat (AMF), alone or in mixture with its low or high melting temperature fraction (olein- or stearin-rich fraction, respectively), were aged at 4 °C for 24 h and then submitted to a whipping test at this temperature. We observed that the AMF/olein emulsion presented less crystalline fat content, and a higher ability for air incorporation than the other two emulsions. In addition, air bubbles formed in the AMF/olein-rich emulsion presented a more uniform size distribution, a smaller proportion of bubbles higher than 50 μm, and they appeared to be coated with a thicker layer of fat droplets. These results indicated that foam-structure forming properties in reduced milk fat emulsions can be enhanced by lowering the proportion of saturated triglycerides. 相似文献