超临界CO2萃取西瓜籽油的研究

采用超临界CO2流体萃取方法从西瓜籽中提取西瓜籽油.利用正交实验探讨萃取压力、萃取温度、萃取时间、夹带剂用量对西瓜籽油萃取率的影响.结果表明,影响西瓜籽油萃取率的因素主次顺序为:萃取压力>萃取时间>萃取温度> 夹带剂用量;最佳提取条件为萃取压力40 MPa,萃取温度45℃,萃取时间150 min,夹带剂乙醇用量7%.在最佳条件下西瓜籽油萃取率为52.18%.     

超临界CO_2法萃取芹菜叶黄酮

在考察超临界CO2萃取温度、萃取压力、萃取时间以及夹带剂用量等单因素对黄酮萃取率影响的基础上,采用Box-Behnken响应曲面设计法,建立影响因素和黄酮得率之间的回归方程。结果表明:萃取温度、萃取压力、萃取时间对超临界CO2萃取芹菜中黄酮工艺影响极显著,夹带剂用量影响显著,最佳提取工艺条件为萃取温度70℃、萃取压力30 MPa、萃取时间2.5 h、夹带剂用量为1 mL/g。该条件下黄酮得率为9.03%,与预测值相近,差异不显著,符合实验要求。     

超临界CO2流体萃取荷叶总生物碱工艺研究

采用超临界CO2流体萃取技术研究荷叶总生物碱的提取工艺条件.以萃取温度、萃取压力、夹带剂流速、萃取时间为工艺参数,通过单因素试验和正交试验相结合的方法,确定超临界CO2流体萃取荷叶总生物碱的最佳工艺,即:萃取温度55℃,萃取压力20MPa,夹带剂流速0.2 mL/min,萃取时间2h.各因素影响荷叶总生物碱得率的次序为:萃取温度＞萃取时间＞萃取压力＞夹带剂流速.最佳工艺验证试验的荷叶总生物碱得率为318.45μg/g.     

超临界CO2萃取花椒果皮总黄酮的工艺

以七年生花椒果皮为原料,进行超临界CO2萃取分离花椒总黄酮的工艺研究,采用硝酸铝-亚硝酸钠法对萃取物中的总黄酮含量进行了定量测定,重点考察了萃取温度、萃取压力、萃取时间以及夹带剂用量对总黄酮得率的影响.正交实验结果表明,各种因素对花椒萃取率的影响的程度从高到低依次为:萃取温度＞萃取压力＞萃取时间＞夹带剂用量.超临界CO2流体萃取花椒黄酮的优化条件为:萃取温度为50℃,萃取压力35MPa,萃取时间150min,夹带剂用量4mL/g,此时花椒总黄酮提取率为19.574％.     

花椒有效成分的CO_2超临界萃取工艺

通过对影响花椒CO2超临界萃取的因素:萃取压力、时间、温度、CO2流量、夹带剂用量进行考察,由正交试验确定了较优萃取工艺,对花椒有效成分提取率的影响依次为:萃取压力＞萃取时间＞萃取温度＞CO2流量＞乙醇夹带剂用量;得出超临界萃取的较优工艺,以期为花椒CO2超临界萃取的工业化大生产提供科学依据.     

超临界CO2萃取核桃油的研究

研究了影响核桃油超临界CO2流体萃取的因素,在试验条件下,其影响因素次序为:夹带剂、萃取压力、CO2体积,萃取温度影响不大.优化了超临界CO2流体萃取核桃油的工艺条件:夹带剂无水乙醇,用量为投料量的质量分数的10%;萃取压力30 MPa,萃取温度35℃,萃取时间3.5 h,CO2流量15～20kg/h.用气相色谱法分析了超临界CO2流体萃取核桃油的脂肪酸酸组成和含量,其不饱和脂肪酸含量较高.     

超临界CO_2萃取姜黄素工艺中试研究

采用超临界CO2萃取姜黄素,萃取釜的萃取压力、夹带剂的用量对姜黄素萃取率影响较大,但萃取压力25 MPa夹带剂用量6倍以上时,萃取率差异较小;萃取温度对姜黄素萃取率影响较小,萃取温度40℃以上时萃取率均在92%以上。试验得出超临界CO2萃取姜黄素的工艺条件     

超临界CO2萃取车前草中熊果酸的工艺研究

目的:研究超临界CO2萃取车前草中熊果酸的工艺条件.方法:探讨萃取压力、萃取温度、萃取时间、夹带剂类型及用量对熊果酸收率的影响,确定了超临界CO2萃取车前草中熊果酸的适宜条件.结果:超临界萃取最优条件为萃取压力35 MPa,萃取温度为40℃,选择无水乙醇为夹带剂,夹带剂质量分数为20%,萃取时间2 h,CO2流量为20 L/h,产品的出膏率为3.58%,萃取物中熊果酸的含量为6.93%.结论:该法与传统方法相比,具有操作简便快速,溶剂用量少,有效成分提取率高等优点.     

炒青绿茶儿茶素超临界CO_2萃取工艺优化研究

采用单因素试验和正交试验对炒青绿茶儿茶素超临界CO2萃取工艺进行探讨,确定萃取效果影响的程度从高到低依次为:萃取压力夹带剂乙醇用量萃取时间萃取粒度,最佳萃取工艺为:底物与夹带剂(乙醇)之比为100g/250mL,萃取压力25MPa,萃取温度50℃,粒度为60目,萃取120min。按照该工艺茶叶中儿茶素粗提物的得率为6.0536%。     

超临界CO2萃取芦笋中总黄酮的工艺研究

采用超临界CO2萃取技术对芦笋中的黄酮类化合物进行了萃取研究，运用L9（3^4）正交表系统研究了萃取压力，萃取温度，萃取时间以及夹带剂用量对萃取率的影响。确定了超临界CO2萃取芦笋总黄酮的最佳工艺条件为：温度为70℃、时间为2h、压力为30MPa、夹带剂（75％乙醇）用量为2．0mL／g。此条件下得到总黄酮比率为1．35％，其黄酮得率是常规溶剂乙醇提取法总黄酮得率的2．7倍。     

CO_2超临界流体萃取技术提取甜橙皮精油的研究

设计和建立了一套超临界萃取试验装置,实现了用超临界ＣＯ２萃取洋葱油的实验,着重研究了萃取压力、温度和时间等重要参数对萃取率的影响。     

CONCENTRATION OF ONION JUICE VOLATILES BY REVERSE OSMOSIS AND ITS EFFECTS ON SUPERCRITICAL CO2 EXTRACTION

Supercritical carbon dioxide extraction of onion oil at moderate temperatures produces aproduct which is characteristic of the fresh flavor of onions. It was attempted to improve extraction efficiency by concentrating the onion juice by reverse osmosis prior to supercritical CO₂ extraction. Reverse osmosis was carried out for all combinations of 600, 700, and 800 psi feed pressure and 25 and 35C. The juice was concentrated to 18 ^oBtix and then subjected to supercritical CO₂ extraction. The effect of concentration on the extraction process was evaluated by comparing the yields of extracts from concentrated juice with that of single strength juice. Concentration of onion juice by reverse osmosis improved the efficiency of supercritical CO₂ extraction of onion oil and did not alter its characteristic fresh aroma.     

Supercritical carbon dioxide extraction of onion oleoresin

Supercritical carbon dioxide (SC-CO₂) extraction on a laboratory-scale, was applied to produce oleoresin from dried onion (Allium cepa L). The goal of this work was to determine the optimal conditions of extraction for producing oleoresin with the highest yield and the best quality. A polynomial model was developed on the data. The square of correlation coefficient was R²=0·9022 (at P⩽0·05). The statistical analysis showed that the extraction pressure, temperature, and time have significant influence on the yield of the oleoresin. Increasing these parameters resulted in an increase in the yield. Maximum yield was obtained when the extraction pressure and temperature were above 350 bar and 57°C, respectively. At the lowest pressure (150 bar) applied the highest concentration of sulphur was produced in the oleoresin. The concentration of sulphur increased as a function of temperature when the pressure was maintained at 300 and 400 bar. The composition of volatile compounds of oleoresin differed from that of distilled onion oil. © 1998 SCI.     

Comparison of yields and quality of nutmeg butter obtained by extraction of nutmeg rind by soxhlet and supercritical carbon dioxide (SC-CO2)

Nutmeg is a native South East Asian plant which has medicinal properties. In this work, supercritical extraction was studied in order to obtain experimental data of the influence of pressure, temperature and particle size and in comparison to soxhlet extraction. Supercritical extraction was conducted at operating temperatures of 40, 50 and 60 °C, operating pressures of 20.7, 27.6, 34.5 and 41.4 MPa and dynamic extraction time was 90 min. The effect of three different sieved particle sizes ?0.500, ?1 mm and ?2 mm on the extraction yield was examined. The results show that the highest yield was 38.8 g oil/100 g sample obtained under extraction temperature of 60 °C, pressure 41.4 MPa using particle size of ?0.5 mm. Soxhlet extraction yields 34 g oil/100 g sample for 6 h of extraction time. The GCTOFMS shows that the supercritical extracts exhibited significantly higher aromatic ether group comparable to those obtained by soxhlet.     

圆葱中精油及黄酮类提取工艺研究

研究了提取溶剂种类、浸提温度、浸提时间、料液比等对圆葱精油及黄酮提取率的影响。试验表明,选择乙酸乙酯作为提取溶剂,料液比为1∶1.25(g∶mL),浸提温度40℃,浸提时间120min时圆葱精油提取率可达到0.19%;在超声波辅助萃取圆葱皮中总黄酮的研究中,乙醇浓度80%,料液比1∶10(g∶mL),超声温度40℃,超声时间15min时提取率最高。     

紫皮洋葱油索氏提取工艺优化

采用响应曲面法对紫皮洋葱油提取工艺进行优化。以紫皮洋葱油得率为指标,采用索氏提取法,对提取溶剂,提取时间,料液比和回流温度等提取条件进行单因素试验。在此基础上,根据Box-Benhnken中心组合方法进行三因素三水平的试验设计,并进行响应面分析。结果表明,紫皮洋葱油最佳提取工艺条件为:石油醚为溶剂,料液比为3.64/80(g:mL),提取时间为3.83h,回流温度为78.49℃。在此工艺条件下,紫皮洋葱油得率理论值为0.462%,实测值为0.470%,与理论值相比,相对误差为1.73%。     

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.     

椪柑籽油超临界提取工艺的优化

利用临界CO2萃取技术提取椪柑籽油。在单因素试验的基础上,采用Box-Behnken中心组合设计对椪柑籽油超临界CO2萃取工艺中的时间、温度、压力和流量4因素的最优化组合参数进行定量研究,得到各因素与椪柑籽油得率关系的数学模型。结果表明:最佳的工艺条件为萃取压力34.4MPa、CO2流量25.8L/h、萃取时间147.6min、萃取温度39.3℃。该条件下,椪柑籽油提取得率的理论值为45.95%,实测值为(45.12±1.36)%(n=3),说明回归模型能较好地预测椪柑籽油的提取得率。     

溶剂法提取洋葱油的工艺研究

系统研究了样品不同的预处理方法、浸提溶剂、浸提时间等对洋葱油质量和得率的影响，确定了一条操作简单的洋葱油提取工艺，较佳条件为：新鲜洋葱直接匀浆，常温下用石油醚浸提9h，这一工艺条件下所得的洋葱油质量好、得率为0．158％；采用索氏提取法洋葱油得率可提高到0．440％。     

超临界CO2流体萃取-精馏小米糠油

采用超临界CO2萃取-精馏技术从小米细糠中提取小米糠油。研究萃取压力、萃取温度、萃取时间、CO2流量对出油率的影响,以及压力、温度对精馏的影响。结果表明：在萃取压力30MPa、萃取温度45℃、萃取时间2h、CO2流量50kg/h的萃取条件下小米糠粗油的出油率可达19.69%。在精馏柱压力10MPa、4个精馏柱温度分别为40、45、50、55℃条件下,对粗油进行精馏得到小米糠精油。通过检测,超临界萃取法提取的小米糠油含有较高的不饱和脂肪酸,尤其是含有高达67.8%的亚油酸,且各项理化指标均优于市售小米糠油。