1、大学英语四六级写作高分句型 玫瑰天竺葵油的超临界流体萃取 学院 工程技术学院 专业 食品科学与工程 姓名 刘晓旭 学号 09105046Production of rose geranium oil using supercritical fluid extraction生产的玫瑰天竺葵油的超临界流体萃取AbstractThe present work aims to apply the supercritical fluid extraction (SFE) with carbon dioxide as a clean technology to extract the natural es
2、sential oil from a Portuguese-grown rose geranium (Pelargonium sp.). Geranium oil is an important ingredient in perfumery as middle note and is a natural resource with potential to be explored in Portugal, 摘要:这个工作的目的是申请把超临界流体萃取二氧化碳作为一项清洁技术来提取葡萄牙生长的天然挥发油。天竺葵精油作为中调香油的一个重要组成成分,是一个在葡萄牙探索的潜在的自然资源,since t
3、his plant is well adapted to our climate and soil. A new SFE equipment was designed and constructed and it was used for the extraction of geranium. The obtained extracts were characterised by GC/MS and their organoleptic quality (colour and odour) was evaluated and compared with the materials obtain
4、ed by the traditional techniqueshydrodistillation and organic solvent extraction. 因为这种植物可以很好的适应我们的气候和土壤。一个新的超临界流体萃取设备被设计和建造的,它被用来提取天竺葵。得到的提取物用GC/MS和它们的感官器官(颜色和气味)评估和用传统技术,水蒸馏,有机溶剂得到的材料作比较。The best extraction conditions were: extraction time of 1530 min, temperature of 40 C, pressure of 90100 bar, cu
5、t fresh plant and dynamic mode. The SFE yields varied between 0.019 and 0.22%. The CO2 geranium extract had a superior organoleptic quality, with very fresh natural floralfruity character and a pale yellow colour, most suitable for the use in perfumery。最好的提取条件是:提取时间是1530分钟,温度为40C,压力温度为90100巴,切新鲜的植物和
6、动态模式。这中间变化的超临界流体萃取的产量为0.0190.22%。老鹳草提取物的CO2有优越的感官质量,有新鲜的天然花香,果香和淡黄色的颜色,最适合用于香水。Keywords: Supercritical fluid extraction; Essential oil; Rose geranium (Pelargonium graveolens); Experimental set-up; Process parameters; Fragrance natural material关键词:超临界流体萃取法;玫瑰天竺葵精油(Pelargonium graveolens);实验设置;工艺参数;香味
7、天然材料3.2. Effect of operating parameters3.2 操作参数的影响In this work, the influence of the operating conditions on the extraction yield, chemical composition and organoleptic quality was considered. The extraction parameters herein studied were:time of extraction, pressure, temperature, plant pre-treatmen
8、t and operating mode (static/dynamic). 在这个作品中,影响的操作条件对提取率、化学成分和感官的特性都考虑在内。提取的参数在这里是:提取时间,压力,温度,植物预处理和操作模式(动态)。To analyze the influence of parameters on the composition of the SFE extracts, four groups of key fragrant components representative of the main types of components were considered: F1the mo
9、st volatile fraction, constituted by rose oxide and isomenthone.对超临界流体萃取物的合成物的参数影响进行分析,4组关键的芳香合成物代表的主要类型被考虑在内:F1-最易挥发性馏分,由玫瑰氧化物和异薄荷酮组成。F2the characteristic fraction,constituted by guaia-6,9-diene and citronellyl formate (two components characteristic of geranium oil).F2-特有的馏分,由guaia-6 citronellyl,9-
10、diene甲酸(两部分组成,天竺葵精油)的特点。F3the rose scented fraction, composed of citronellol andgeraniol (rhodinol fraction).F3玫瑰的芳香馏分,由香茅醇和香叶醇组成(玫瑰醇馏分)F4the low volatility fraction, with geranyl tiglate and phenylethyl tiglate.All the fractions were compared with the essential oil composition.F4-低挥发性馏分,有香叶基和巴豆酸苯乙酯
11、,所有的部分与精油的合成物相比较。3.2.1. Extraction time effect3.2.1 提取时间的影响The SFE yield and composition was not significantly affected by the extraction time, as can be seen in Table 4. It is note worthy that for very long extraction time (180 min) the amount of linalool was higher, as can be seen in Table 4, whic
12、h indicates that there was a degradation of geraniol into linalool, due to the long heating and exposure to water vapour, as was explained by Guerere et al. 13.超临界流体萃取的产量和合成物不会被提取时间明显的影响,只可以在4表中看出。它有价值的表明了非常长的提取时间(180分钟)沉香醇的数量越高,可以在表4中看出,这表明香叶醇退化成沉香醇,是因为长时间的热量和曝光成水蒸气,这被Guerere等人解释。3.2.2. Pressure ef
13、fect3.2.2 压力的影响The SFE yield was significantly influenced by the extraction pressure, as can be seen in Table 4. In fact, increasing the extraction pressure from 80 to 160 bar, the yield increased more than 10 times. The higher CO2 density at high pressures increases its solvent power and therefore
14、more substances were extracted.抽取压力对超临界流体萃取的产量产生显著地影响,可以在表4中看出。实际上把提取压力从80巴提高到160巴,产量就被提高多于10倍。在高压力下提高溶解力CO2密度越高,因此越多的物质就会被提取出来。The study of pressure effect on composition is shown in Fig. 4.The most volatile fraction (F1) increased with pressure, while the rose fraction (F3) and the low volatility
15、fraction (F4) amount decreased, more significantly for F4. Considering the characteristic fraction (F2), citronellyl formate followed the increasing trend shown by fraction F1, while guaia-6,9-diene did not change significantly. These results show that only for the more volatile components, the incr
16、ease of the soluble amount with the increasing pressure was significant.压力对合成物的影响的研究在4图中显示。最易挥发性馏分随压力而提高,当玫瑰馏分和低挥发性馏分的数量下降对于F4会更加明显。考虑到特有的馏分,甲酸香茅酯在图1中呈现增长的趋势,同时,9-diene guaia-6没有明显变化,这些结果只显示更多的挥发组分,可溶的成分的数量随着压力增高而增高是显著的。3.2.3. Temperature effect3.2.3 温度的影响It was observed that increasing extraction t
17、emperature from 40 to 100 C the yield decreased three times. This fact reveals that the effect of decreasing the fluid density and thus its solving power is dominant over the increase of vapour pressure of components.观察得到提取的温度从40C 增高到100C,产量降低3倍。这个事实揭示了流体密度缩减的影响和它的解决力量要比合成物蒸汽压力的提高占优势。On the other ha
18、nd, comparing the compositions (see Fig. 5), it can be seen that the temperature affected differently the components behaviour. Rose oxide in F1 and citronellyl formate in F2 had a maximum amount in the extract of 80 C and citronellol in F3 had a maximum at 60 C. 另一方面,对照组成物,可以看到温度对组成物的习性有不同的影响。图1中的玫
19、瑰氧化物和图2中的甲酸香茅酯在80度的提取温度都有最高数量而在图3中的香茅醇在60度数量最高。By contrast, geranyl and phenylethyl tiglates in F4 fraction showed a minimum at 80 C,as well as geraniol in F3,although it is little pronounced. In the case of isomenthone in F1, the effect of temperature is not evident.相反,在图4中的tiglates香叶基苯在80度时数量最小,和图
20、3中的香叶醇相同,尽管有一点点显著。对于图1中的异薄荷酮,温度的影响不是很显著。It can be concluded that for those components that showed a maximum in composition, the effect of increasing vapour pressure with increasing temperature was dominant over the loss of solving power of supercritical CO2, happening the opposite for the ones that
21、showed a minimum. Looking at linalool composition,in spite of its amount was still low compared with theessential oil, it was increasing with the increase of extraction temperature, especially at the higher temperatures of 80 and 100 C, due to the effects already mentioned and described by Guerere e
22、t al. 13可以推断这些合成物在组成上显示出最大数量随着温度的升高而增高的蒸汽压力的影响比超临界二氧化碳的溶解力的损失程度要占优势,这与最小数量对立。看一下沉香醇的组成物,即使它的数量始终比精油低,它业随着提取温度的升高而升高,尤其是在80度到120度的更高的温度下,这些影响已经被Guerere等人提到和描述了。The extraction yield obtained by using ground frozen plant was 25% higher than the yield obtained using cut fresh plant. This is explained by
23、 the fact that grounding the plant,the contact surface area is increased,improving the extraction.通过用研磨冻结的植物提取的产量要比通过切取新鲜植物而获得的产量高25% 。接地的植物,接触面升高,产量就会升高。 Note that the increase of yield means that more material is extracted, but not necessarily that there is an increase in the amount of volatile fr
24、action yield because non-volatiles are also extracted. Considering the influence of this parameter on composition,the content in the most volatile components (F1) and rose scented fraction (F3) decreased 8 and 20%, respectively, while the amount of guaia-6,9-diene in F2 increased 27%. For fraction F
25、4 the effect was not significant. This result revealed that there was loss in the volatile components during the process of grinding, even though the plant was ground frozen, while thenon-polar components (F2), having more affinity to wax material in the plant, are better extracted when the contact
26、area with the solvent is bigger.产量的提高意味着更多的原料被提取出来但是不是很明显的意味着挥发性馏分数量的提高,因为非挥发物也被提取出来,考虑到这个参数对合成物的影响,最易挥发物和玫瑰芳香成分的含量会降低8%到20%,分别的说,guaia-6的数量提高27%。对于图4影响还不是很显著,这个结果揭示了在研磨过程中挥发性合成物有所损失,尽管植物被研磨冻结,当thenon-polar元件(F2),有着更多的亲和力,能在植物的蜡状材料时,溶解力更大更易被提取。3.2.5. Operating mode effect3.2.5 操作模式的影响The extraction
27、yield using dynamic operating mode increased 43% compared to the yield obtained with static operating mode.The dynamic mode favoured the extraction of the more volatile fraction (F1) and the characteristic fraction (F2). For the rose scented fraction (F3) and low volatile fraction (F4), their amount
28、 decreased using the dynamic mode, showing that the low volatility compounds have a slower dissolution in SFE solvent and therefore the dynamic time used was not enough to extract their entire amount.使用动态的操作模式的提取率和静态的操作模式获得的产量比起要高于43% ,动态模式是因为更多的挥发性馏分和特有馏分提取物而更占上风,至于玫瑰的芳香馏分和低量的挥发性馏分,它们的数量在使用动态模式中降低,
29、显示了低量的挥发性化合物在超临界流体萃取法溶剂中溶解的更慢,因此动态的时间不足够用于提取全部的数量。3.3. Organoleptic description3.3 感官的描述The absolutes from SFE extracts showed a pale yellow yellow colour, having a floralfruity natural clean fresh character, resembling the actual plant scent but with the floralfruity note more striking. Thestillort
30、eaoff notes (boiled plant),characteristic of geranium essential oil but not desired, were not noticed in SFE absolutes.The floral character is due to the components geraniol and citronellol, while the fruity nuances derive from their formates, acetates and tiglates and the freshness is imparted by i
31、somenthone. The concrete was a yellow paste, with a sweet-floral balsamic odour, most probably due to the presence of waxes. The smelling strips were practically not stained, so the non-volatiles content was low.从超临界流体萃取法中提取的纯物质呈现淡黄色,具有天然,新鲜,花果香味的特性,类似真实植物的气味更加显著。off笔记的still多尔tea(煮植物、特色的天竺葵精油但不理想,都没
32、有注意到在萃取绝对化。植物的特性是由于成分和citronellol醇,而圆润的细微差别源自于它们的甲酸盐,醋酸盐和被异薄荷酮给予,凝结物是一个黄色的糊状物,带着一个甜植物的香脂的气味,很有可能归因于蜡状物的存在,有气味的条几乎没有败坏,所以非挥发性成分含量很低。The colour was more intense for the extracts obtained at lower temperature (40 C), higher pressure (160 bar), using smaller particle size (ground plant) and dynamic operating mode. The absolute from SFE extract obtained at very high pressure presented a greener odour nuance due to its higher amount of rose oxide (strong odour reminiscent of geranium and carrot leaves 1). The