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A novel method using ethanol and ultrasound to extract oil from cream obtained from enzyme-assisted aqueous extraction of soybean oil was developed. To evaluate the relationships between operating variables and free oil yield and to maximize the free oil yield, response surface methodology was introduced in this work. The developed regression model was fitted with R 2 = 0.9591. Optimized variables were: ethanol concentration of 73 %, ethanol addition volume of 0.55 L/kg, ultrasound power of 427 W, ultrasound time of 47 s, and ultrasound temperature of 53 °C. The free oil yield from the cream under the above conditions was 92.6 ± 3.4 %. Scanning electron microscopy (SEM) was used to evaluate the effect of ultrasonic treatment on ethanol-treated cream, and the SEM images clearly showed that the ultrasound treatment affected dispersing and fracturing of the microstructure of ethanol-treated cream.  相似文献   

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Chemical Properties of Virgin Coconut Oil   总被引:1,自引:0,他引:1  
A study on the commercial virgin coconut oil (VCO) available in the Malaysian and Indonesian market was conducted. The paper reported the chemical characteristics and fatty acid composition of VCO. There was no significant difference in lauric acid content (46.64–48.03%) among VCO samples. The major triacylglycerols obtained for the oils were LaLaLa, LaLaM, CLaLa, LaMM and CCLa (La, lauric; C, capric; M, myristic). Iodine value ranged from 4.47 to 8.55, indicative of only few unsaturated bond presence. Saponification value ranged from 250.07 to 260.67 mg KOH/g oil. The low peroxide value (0.21–0.57 mequiv oxygen/kg) signified its high oxidative stability, while anisidine value ranged from 0.16 to 0.19. Free fatty acid content of 0.15–0.25 was fairly low, showing that VCO samples were of good quality. All chemical compositions were within the limit of Codex standard for edible coconut oil. Total phenolic contents of VCO samples (7.78–29.18 mg GAE/100 g oil) were significantly higher than refined, bleached and deodorized (RBD) coconut oil (6.14 mg GAE/100 g oil). These results suggest that VCO is as good as RBD coconut oil in chemical properties with the added benefit of being higher in phenolic content.  相似文献   

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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   

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This study presents the green and effective aqueous enzymatic process assisted microwave extraction (AEME) to preparate macadamia nut oil (MNO). The conditions of the extraction process are optimized (extraction temperature 50 °C, extraction time 64 min, enzyme concentration 1.60% (w/w), and irradiation power 450 W). An oil yield of 58.09 ± 0.63% is achieved under these optimal conditions. The scanning electron micrograph (SEM) analysis of nuts before and after extraction illustrates that AEME promotes the emancipation of oil stored within the organelles. Gas chromatography-flame ionization detector (GC-FID) analysis reveals the fatty acid compositions of MNOs obtained by AEME and the Soxhlet extraction (SE) are similar and mainly dominated by monounsaturated fatty acids beneficial to human health which is higher in MNO than in any other known food. Moreover, gas chromatography-mass spectrometry (GC-MS) analysis reveals higher amounts of more odoriferous oxygenated terpenes is present in the MNO extracted by AEME in comparison with SE. The physicochemical properties of AEME oil are more excellent than those of SE oil. Moreover, AEME oil exhibits superior antioxidant capacities. In conclusion, green AEME gives relatively satisfactory yield and better retains the fragrance and functionality of MNO. Practical Applications: The present study provides a green extraction method and valuable data for the process design as well as industrial scale-up applications. In addition, compared to the nonsustainable and environmentally nonfriendly traditional method, AEME preserves the initial composition of the flavor substances and enhances the extraction of healthy beneficial compounds in MNO. Therefore, AEME oil can be used to develop functional edible oils or even in medicinal, cosmetic, and pharmaceutical preparations.  相似文献   

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刘春娟 《广东化工》2008,35(3):53-56
微波萃取技术作为一种新的萃取分离技术,为样品预处理方法带来了许多新的思维,已受到国内外许多行业科研工作者的广泛关注,具有很大的发展潜力和应用前景。文章综述了最近几年的微波萃取技术发展及其应用。  相似文献   

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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   

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水酶法提取大豆油   总被引:1,自引:0,他引:1       下载免费PDF全文
The procedure of enzymatic aqueous extraction of soybean oil was assessed when two-step controlled enzymatic hydrolysis was applied. With aqueous extraction of soybean oil-containing protein, the highest yield of oil was 96.1% at the optimized conditions studied. Soybean oil-containing protein was hydrolyzed and resulted in releasing part of oil. The separated protein that contained 40% oil was enriched due to its adsorption capacity of released oil, the average oil extraction yeild reached 93.5%. Then the high oil content protein was hydrolyzed again to release oil by enzyme, the oil extraction yeild was 80.4%. As a result, high quality of soybean oil was obtained and the content of total oil vield was 74.4%.  相似文献   

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微波诱导法萃取印楝种壳中印楝素的研究   总被引:8,自引:0,他引:8  
研究了利用微波诱导法萃取印楝种壳中印楝素的新方法 ,以HPLC分离并测定所萃取的印楝素含量。结果表明 ,与常用的甲醇室温浸提法和丙酮 45℃萃取法相比 ,微波诱导萃取法不仅萃取率高 ,而且萃取速度快 ,效率高  相似文献   

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微波辅助萃取煤的实验研究   总被引:1,自引:0,他引:1  
陈红  李建伟  逯俊庆  葛岭梅 《煤化工》2007,35(4):52-55,63
在微波辅助下,以神府煤为主要研究对象,四氢呋喃、丙酮、甲醇为溶剂,考察了萃取温度、时间、溶剂量及煤粒度对萃取率的影响,结果显示:使上述3种沸点接近的不同溶剂萃取率达到最佳值,所需要的萃取温度、溶剂量及煤粒度相差大;同时探讨了以四氢呋喃、丙酮、N,N-二甲基甲酰胺为溶剂,对不同变质程度煤的微波辅助萃取效果,结果是变质程度相似的煤在相同萃取条件下萃取率不同。运用红外光谱现代分析技术,对神府脱灰煤和四氢呋喃抽提残煤的结构进行对比分析,结果表明萃取并没有破坏煤的大分子结构。  相似文献   

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采用微波辅助水提法从金莲花中提取有效药用成分总黄酮。通过单因素和正交法实验研究了各种因素对黄酮提取率的影响。实验结果确定最佳工艺条件为:微波功率560w、辐照时间40s、固液比1:40、辐照次数2次,最大黄酮提取率为24.19%。  相似文献   

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微波辅助提取杨梅果肉中的黄酮类化合物   总被引:5,自引:0,他引:5  
研究了在微波辅助下,以乙醇为萃取剂提取杨梅果肉中的黄酮类化合物的工艺条件。分别以乙醇体积分数、固液比、微波档位、处理时间为单因素进行试验,最后用正交试验法确定最佳提取工艺。结果表明,在乙醇体积分数为60.0%,固液比为1:40,微波档位为低档,处理时间为4.0 min时,黄酮类化合物提取率最高,为3.45%,与传统工艺相比,处理时间大幅度减少,提取率有了显著提高。  相似文献   

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以柚子皮为原料,微波协同提取柚皮中果胶。采用单因素试验和正交试验,对微波协同提取柚皮中果胶的提取工艺进行优化研究。探讨了液料比、pH值、辐射时间、微波强度等因素对柚皮中果胶提取率的影响。试验结果表明,微波协同提取lOg粒径为0.25mm的柚皮粉末中果胶的最佳工艺条件为:总液料质量比30:1,提取液pH2.0,微波功率450W,提取时间60s。提取液经硫酸铝盐析,析出沉淀用酸化醇处理脱盐,过滤,滤渣用乙醇反复洗涤干燥即得果胶,产率14.7%。与加热提取法比较,微波协同提取能大大缩短提取时间,并提高了果胶的产率。  相似文献   

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微波和超声波辅助提取穿心莲内酯   总被引:1,自引:1,他引:1  
用正交法对微波和超声波辅助提取穿心莲内酯的工艺条件进行优化。微波辅助法提取穿心莲内酯的最佳工艺条件为温度40℃、提取溶剂为体积分数75%的乙醇、提取时间8 min;超声波辅助法提取穿心莲内酯的最佳工艺条件是提取溶剂为体积分数75%的乙醇,超声效率40%、超声时间50 min。微波提取法的平均回收率为99.9%,RSD为0.31%;超声波提取法的平均回收率为100.5%,RSD为0.21%。与超声波提取法相比,微波提取法提取时间较短,提取得率较高。  相似文献   

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微波辅助提取紫薯花青素的研究   总被引:2,自引:0,他引:2  
王道武  文茜  张龙 《广东化工》2010,37(12):24-26
文章以紫薯为原料,在微波条件下萃取其花青素,探讨了微波的辐射时间,温度,液固比,提取剂浓度对紫薯花青素萃取的影响,并采用大孔树脂AB-8纯化提取液,将纯化后的提取液进行反相高效液相色谱分析其成分。实验结果表明,紫薯花青素微波最佳提取条件为:辐射时间60 s,温度50℃,液固比40∶1,提取剂为1%HCl-95%乙醇溶液,最佳酸醇比为50∶50。  相似文献   

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