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1.
Aqueous enzymatic extraction (AEE) is an environmentally friendly edible‐oil‐extraction process that can also provide edible protein. However, the AEE process may form a stable emulsion in most cases, which seriously limits the large‐scale industry applications for producing vegetable oils. In this study, the salt‐assisted microwave radiation demulsification of the oil‐rich emulsion prepared with AEE from peanuts is investigated. The microwave demulsification method is compared with other conventional demulsification methods, including heating, and freezing–thawing. The salt‐assisted microwave demulsification of the emulsions shows a greater free oil yield than conventional heating demulsification. Moreover, the microwave demulsification shows a similar free oil yield in less time than freezing–thawing method. Under the optimal operating conditions of demulsification, the free oil yield can reach 92.3% with CaCl2‐assisted microwave demulsification for only 2 min. In addition, the oxidative properties and the fatty acid compositions of the demulsified peanut oil are investigated. No significant difference in the fatty acid composition is observed among salt‐assisted microwave, freezing–thawing, and heating demulsified oil. The oxidative properties of the salt‐assisted microwave demulsified peanut oil is better than the conventional heating demulsified oil. Thus, salt‐assisted microwave demulsification provides a quick and effective demulsification method to obtain vegetable oils with high quality. Practical Applications: Aqueous enzymatic extraction (AEE) is an environmentally friendly edible‐oil‐extraction process. To solve the problem of stable emulsion formed during AEE process, the salt‐assisted microwave demulsification of the oil‐rich emulsion prepared with AEE is developed with high efficiency (demulsification for 2 min). In addition, the oxidative properties of the microwave demulsified oil is better than the conventional heating demulsified oil.  相似文献   

2.
溶剂萃取新技术述评   总被引:2,自引:0,他引:2  
易筱筠  古国榜 《广东化工》2000,27(4):10-13,19
本文就溶剂萃取技术的新进展作一评述,介绍了近年来发展的几种淀粉地取新技术:超临界流体萃取、反胶团萃了 波萃取、微波萃取、电泳萃,磁场协助萃取、等。  相似文献   

3.
Recent technological advances and the development of new methods has provided an opportunity to obtain highly purified natural bioactive compound extracts with potential for the treatment and prevention of human diseases. The use of hazardous and toxic solvents for the extraction and processing of bioactive compounds from plant materials is considered a problem for health, safety and environmental pollution. Advanced technology aims to increase production of the desired compounds and find an alternative to using toxic solvents in the extraction of bioactive compounds from plant materials. The ever growing interest in plant bioactive compounds and today's concerns about environment issues have led to an increased need for an efficient and green extraction method. This review is focused on the extraction of bioactive compounds from plants using advanced and environment‐friendly methods such as supercritical fluid extraction, microwave‐assisted extraction, ultrasound‐assisted extraction and similar techniques that can extract rapidly and free from organic residues. An updated overview of the bioactive compounds present in the plant Phaleria macrocarpa and its extraction, fractionation, purification and isolation is provided. The advantages and disadvantages of both conventional and non‐conventional extraction methods are also discussed in this review. © 2014 Society of Chemical Industry  相似文献   

4.
超声强化超临界CO_2萃取葵粕绿原酸工艺   总被引:2,自引:0,他引:2  
阳元娥 《广东化工》2010,37(10):51-52,61
绿原酸具有抗氧化、清除自由基、抑制突变与抗肿瘤等生理活性。考察了萃取温度、压力、时间、流体流量和超声功率密度对超声超临界CO2萃取绿原酸的影响,结果表明,超声波的加入可以缩短超临界CO2萃取时间、降低CO2流量和提高萃取率。工艺优化后的条件为:70%乙醇加入量为400mL/100g原料,萃取温度、压力、时间、CO2流量分别为50℃、30MPa、3.5h、3.0L/h,超声频率和功率密度分别为20kHz、100W/L。优化条件下绿原酸的萃取率达4.71%  相似文献   

5.
考察当归挥发油的不同提取方法。文中用超临界CO2流体萃取法和微波辅助萃取法研究萃取当归挥发油。实验表明:超临界CO2萃取最佳工艺条件为萃取压力25 MPa、分离釜Ⅰ解析温度55℃、萃取温度45℃,提取率约1.9%;微波辅助萃取最佳工艺条件为无水乙醇为提取溶剂,微波功率800 W、微波辐射时间150 s、液料质量比为4.71∶1,提取率约11.2%。微波辅助萃取法取得当归油的收率高于超临界CO2萃取法。微波辅助萃取法萃取当归挥发油收率高,但外观品质较超临界萃取的当归挥发油差。  相似文献   

6.
煤化工有机废渣是煤化工生产过程中产生的有毒有害的有机固体废弃物,有强烈的刺激性气味,对人类及环境都有巨大的危害,一般归属于危险废物。为了更加有效地处理这些废渣,在分析国内外煤化工有机废渣处理技术的基础上,对煤化工有机废渣的各种萃取处理技术——普通溶剂萃取分离法、超临界萃取分离法、溶剂油萃取分离法、离子液体溶剂萃取分离法、切换溶剂萃取法等进行了详细介绍,并比较了各方法的优缺点,对比分析了各类萃取溶剂、萃取工艺,以期为未来煤化工有机废渣的处理提供参考。  相似文献   

7.
In this work, the ultrasound‐assisted extraction (UAE) of canola oil from canola seeds pretreated with microwaves using ethanol 99% as solvent is studied. Different process parameters are evaluated, such as extraction time, temperature, solid:solvent ratio, and ultrasound amplitude, optimizing the process using response surface methodology. Under optimum conditions, the extraction time is decreased by up to 75% with respect to conventional extractions, obtaining an oil with a higher content of total tocopherols and canolol, and with oxidation indexes within the established standard limits. The addition of a microwave pretreatment to the UAE with ethanol 99% shows a synergic effect between both processes, improving the oil yield. The results obtained in this study show the potential of the use of UAE for the extraction of canola oil using a green solvent, reducing processing times, environmental pollution, and achieving an oil of high quality and antioxidant concentration. Practical Application: The industrial use of petroleum‐derived solvents such as hexane has problems concerning sustainability, environment, and safety. In recent years, the use of “green” solvents for the extraction of vegetable oils began to be studied; however, it is necessary to develop stages that allow improving the extraction process by increasing the yield, reducing the processing times, and optimizing the oil quality. In this sense, ultrasound allows to shorten the extraction times while microwave pretreatments applied to canola seeds generate an increase in the concentration of antioxidants in the oil, facilitating the implementation of a “green” process in the industrial production.  相似文献   

8.
齐墩果酸是女贞子中的主要有效成分。综述了近年来女贞子中齐墩果酸的提取工艺及测定方法。提取工艺包括溶剂提取法、半仿生提取法、超临界流体萃取法、超声波提取法和大孔树脂吸附法。测定方法包括薄层扫描色谱法、气相色谱法、高效液相色谱法和毛细管胶束电动色谱层析法。  相似文献   

9.
微波萃取技术及其应用   总被引:10,自引:0,他引:10  
张成  贾绍义 《化学工业与工程》2004,21(6):444-447,478
微波萃取技术作为一种新型高效的萃取技术,是近年来的研究热门课题。微波可以穿透萃取介质,直接加热物料,能缩短萃取时间和提高萃取效率。本文对近年的微波萃取技术以及其研究做了综述,介绍了微波萃取的特点、主要影响因素及其应用。  相似文献   

10.
Extraction of rice brain oil using supercritical carbon dioxide and propane   总被引:1,自引:0,他引:1  
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   

11.
主要从水蒸气蒸馏法、溶剂萃取法、加速溶剂法、同时蒸馏法、超临界流体萃取法、微波和超声波辅助萃取法、酶提取法、半仿生提取法及固相微萃取技术等方面介绍了艾叶挥发油提取工艺的研究进展。以期为艾叶挥发油的开发研究及应用提供参考。  相似文献   

12.
吴良彪  王建荣 《广东化工》2012,39(14):63-64,58
文章对辣椒红色素的提取进行了较为详尽的研究。结果表明,适宜选用乙醇作为提取剂,提取液的最大吸收波长为471 nm;佳工艺条件是提取温度为55℃;提取时间2.5 h;物料比(g/ml)为1∶6.5。对微波辅助提取辣椒红色素的工艺进行了研究,最佳工艺条件:即微波功率为大火(600 W),微波作用12 min。该工艺具有溶剂用量少,提取周期较短,提取率较高等特点。且验证实验表明,该工艺条件操作稳定,有较好的重复性。  相似文献   

13.
Sunflower (Helianthus annuus L.) seed represents an important source for edible oil and its protein fraction is also recognised as valuable for human consumption when suitably purified from polyphenols, which negatively affect colour and nutritional value. On this basis, a main research has been developed, with the aim of testing the technical feasibility of a supercritical fluid extraction (SFE) process involving a preliminary supercritical CO2 (SC‐CO2) extraction of oil from sunflower de‐hulled seeds, followed by the removal of polyphenols from de‐fatted meal by means of ethanol coupled with SC‐CO2. The paper reports the experimental protocol followed, together with the kinetics of the extractions, knowledge of which allows the optimisation of working parameters and the determination of process yields.  相似文献   

14.
Batch solvent extraction techniques have been widely explored. On understanding its potential significance, this article aims to review kinetics and modeling of various extraction techniques which involve assisted means including microwave-assisted extraction (MAE), ultrasonic-assisted extraction (UAE), pulse electric field (PEF) and high voltage electrical discharge (HVED). This review includes a detailed discussion of the instrumental setup, extraction mechanisms and their distinct advantages and disadvantages. Additionally, the impact of the operating parameters on the extraction kinetics of the mentioned techniques are highlighted. The review also covers the mathematical modeling based on Fick's law, chemical rate law and empirical models. The established kinetic models of various extractions are also summarized to facilitate better understanding.  相似文献   

15.
Extraction yields and fatty acid profiles from freeze-dried Chlorella vulgaris by microwave pretreatment followed by supercritical carbon dioxide (MW-SCCO(2)) extraction were compared with those obtained by supercritical carbon dioxide extraction alone (SCCO(2)). Work performed with pressure range of 20-28 Mpa and temperature interval of 40-70 °C, gave the highest extraction yield (w/w dry weight) at 28 MPa/40 °C. MW-SCCO(2) allowed to obtain the highest extraction yield (4.73%) compared to SCCO(2) extraction alone (1.81%). Qualitative and quantitative analyses of microalgae oil showed that palmitic, oleic, linoleic and α-linolenic acid were the most abundant identified fatty acids. Oils obtained by MW-SCCO(2) extraction had the highest concentrations of fatty acids compared to SCCO(2) extraction without pretreatment. Native form, and microwave pretreated and untreated microalgae were observed by scanning electronic microscopy (SEM). SEM micrographs of pretreated microalgae present tearing wall agglomerates. After SCCO(2), microwave pretreated microalgae presented several micro cracks; while native form microalgae wall was slightly damaged.  相似文献   

16.
天然香料的提取分离技术   总被引:8,自引:0,他引:8  
本文综述了目前传统的天然香料的提取分离技术,如水蒸气蒸馏法、浸提法、压榨法、吸收法、结晶法;新兴的提取分离技术,如分子蒸馏、超临界CO2萃取、微波辅助萃取、加速溶剂萃取、超声提取、色谱法、膜分离、毛细管电泳法和旋转带精馏,以及这些方法的特点与应用前景。  相似文献   

17.
An ultrasound and microwave assisted alternant extraction method (UMAE) was applied for extracting dihydroquercetin (DHQ) from Larix gmelinii wood. This investigation was conducted using 60% ethanol as solvent, 1:12 solid to liquid ratio, and 3 h soaking time. The optimum treatment time was ultrasound 40 min, microwave 20 min, respectively, and the extraction was performed once. Under the optimized conditions, satisfactory extraction yield of the target analyte was obtained. Relative to ultrasound-assisted or microwave-assisted method, the proposed approach provides higher extraction yield. The effect of DHQ of different concentrations and synthetic antioxidants on oxidative stability in soy bean oil stored for 20 days at different temperatures (25 °C and 60 °C) was compared. DHQ was more effective in restraining soy bean oil oxidation, and a dose-response relationship was observed. The antioxidant activity of DHQ was a little stronger than that of BHA and BHT. Soy bean oil supplemented with 0.08 mg/g DHQ exhibited favorable antioxidant effects and is preferable for effectively avoiding oxidation. The L. gmelinii wood samples before and after extraction were characterized by scanning electron microscopy. The results showed that the UMAE method is a simple and efficient technique for sample preparation.  相似文献   

18.
超声波辅助萃取天然植物香料研究进展   总被引:1,自引:0,他引:1  
超声波辅助萃取技术近年已经在天然植物香料萃取方面得到越来越广泛的应用。对超声波(溶剂法)萃取、超声强化超临界CO2萃取和超声-微波协同萃取在天然植物香料提取方面的最新应用及研究进展进行了总结,同时对超声波辅助萃取天然植物香料前景进行了展望。  相似文献   

19.
分别介绍了超声提取工艺、微波提取工艺、超临界CO2萃取工艺的原理、工艺的主要影响因素、工艺的优缺点及工艺在中药提取中的具体应用。与传统的中药提取方法相比,3种新工艺存在着提取率高、选择性高、周期短等明显优势,是未来中药提取工艺的选择方向。  相似文献   

20.
概述了邻苯二甲酸酯类(PAEs)作为聚氯乙烯(PVC)增塑剂的应用、危害,说明了PAEs的理化性质,详细归纳了超声波、微波、超声.微波协同萃取技术的应用及PAEs分析测定方法.通过优化超声波、开放式微波和超声.微波等方式萃取PVC塑料样品中的PAEs的萃取条件,比较了3种不同萃取方式的萃取效率.结果表明,超声.微波协同萃取是比较理想的萃取方式.利用该方法对2种实际塑料样品中PAEs的萃取和分析,成功地定量测定了PVC塑料样品中DEHP、DINP和DBP等邻苯二甲酸酯类增塑剂的含量.该法可用于塑料制品中各类邻苯二甲酸酯类增塑剂的快速萃取和分析.  相似文献   

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