SFE-CO2与分子蒸馏技术分离纯化亚麻籽油中的α-亚麻酸
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摘要
亚麻,又名胡麻,为亚麻科(Linum usitatissimum L)亚麻属一年生草本植物,喜凉爽、干燥气候,是长日照作物,广泛分布于世界各地,有五千多年的种植历史。传入中国后迅速成为中国重要的油料经济作物,历年种植面积约为60万公顷,种子产量约为25-30万吨,本实验以亚麻作为主要原料,用超临界COz萃取技术提取亚麻精油,然后用分子蒸馏对所得的萃取物进行精分离,最后采用GC-MS联用分析仪对得到的蒸出物进行分析。探讨了不同条件(原料预处理、萃取压力、萃取温度、萃取时问、CO2流量、分离压力、分离温度、夹带剂、蒸馏温度、冷凝温度、真空度、转速等)对亚麻精油提取率及其品质的影响,寻找提取亚麻精油的最佳工艺参数。从而为亚麻的综合利用提供理论依据。
超临界流体萃取(supercritical Fluid Extraction)SFE是一种现代分离技术,使用超临界流体作为溶剂。SFE具有处理温度低,萃取挥发性成分效果好,不发生氧化变质的优点与传统的方法相比,可用于色素、香料香精、油脂的萃取等。本实验研究结论结论是超临界CO2萃取胡麻籽油的主要影响因素是萃取压力。萃取温度、萃取时间、CO2流量对实验结果的影响均不显著。经正交实验优选的萃取条件为：CO2流量25L/h；萃取压力30MPa；萃取温度45摄氏度；萃取时间2h。在优选的萃取条件下操作,胡麻籽油的萃取率基本稳定,平均萃取率为36.70%。所得胡麻籽油金黄色、透明。超临界CO.萃取胡麻籽油的萃取率较高,所得的产品较为纯净,不会造成产品污染。因此,避免了溶剂残留和环境污染等问题。
分子蒸馏(Molecular Distillation)又叫短程蒸馏,一种在极高真空、远低于沸点的条件下,利用分子自由程不同的特点完成的液-液分离过程。特别适用于高沸点、热敏性物质的分离,分子蒸馏是在极高真空(1Pa以下)下进行的,而且被蒸馏物受热时间非常短,从而能确保一些较高沸点而又对氧气、热敏感的有机物在蒸馏时不会被氧化、聚合、分解被破坏。应用VKL70型刮膜式分子蒸馏设备对a-亚麻酸进行小试提纯试验,蒸馏温度低,产品不易产生分解变质。并且操作简便,分离效率高,容易实现产业化。应用VKL70型刮膜式分子蒸馏设备对α-亚麻酸进行小试提纯试验,蒸馏温度低,产品不易产生分解变质。并且操作简便,分离效率高,容易实现产业化。试验采用多级操作方式,适宜的分离条件为：蒸馏温度90℃～105℃;操作压力0.3Pa～1.8Pa;进料温度60℃：进料速率90mL/h～100mL/h:刮膜器转速150r/min。经过四级分子蒸馏,可以将原料中的α亚麻酸由原来的67.5%提纯至82.3%。
Flax.(Linum usilalissimiim L) is an annual herb, which likes low temperature and dry climate. It is a long-day crop and widely distributed around the world with5.000years of cultivation history. The study is aimed at extracting oil from flax by Supercritical fluid extraction (SFE) and the molecular distillation(MD).The constituents of distilled oil are analyzed by gas chromatography-mass chromatography. Effects of different extraction conditions on product yield and quality of extracted oil samples are discussed and optimum technology variables are obtained. Thus, theoretical foundations for comprehensive utilization of flax are provided.
Supercritical fluid extraction (supercritical Fluid Extraction) SFE is a modern separation technology, supercritical fluid as a solvent. SFE has a low processing temperature, the effect of extraction of volatile components, oxidative deterioration does not occur compared to the advantages with the conventional method can be used to pigment, fragrance, flavor, grease extraction. The conclusions of this experimental study concluded that supercritical CO2extraction of the main factors of flax seed oil extraction pressure. Extraction temperature, extraction time, CO2flow rate had no significant effects on the experimental results. Orthogonal extraction conditions:the CO2flows25L/h; extraction pressure30MPa; extraction temperature of45degrees Celsius; extraction time2h. Operation, under the extraction conditions in the preferred flax seed oil extraction rate basically stable, the average extraction rate of36.70%. The resulting flax seed oil golden yellow, transparent. Supercritical CO:high extraction flax seed oil extraction rate, the resulting product is more pure and will not cause contamination of the product. Therefore, to avoid the problem of residual solvent and environmental pollution.
Molecular distillation (Molecular Distillation), also known as a short-path distillation, a high vacuum conditions, far below the boiling point of liquid-liquid separation process, completed by the characteristics of the type of the molecular free path. Particularly applicable to high boiling point, separation of the heat-sensitive material, the molecular distillation is carried out under high vacuum (1Pa), and the distillate heating time is very short, so as to ensure a higher boiling point and hot oxygen-sensitive organic matter will not be oxidized during distillation, polymerization, decomposition been destroyed. Wiped film molecular distillation equipment of application VKL70type small scale purification test for alpha-linolenic acid, low temperature distillation, the product is easy to produce the decomposition deterioration. And easy to operate, high separation efficiency, easy to achieve industrialization. Wiped film molecular distillation equipment of application VKL70type small scale purification test for alpha-linolenic acid, low temperature distillation, the product is easy to produce the decomposition deterioration. And easy to operate, high separation efficiency, easy to achieve industrialization. Test uses a multi-stage operation, appropriate separation:distillation temperature of90°C to105°C; the operating pressure0.3Pa to1.8Pa; feed temperature of60°C; feed rate of90ml/h to100mL/h; membrane wiper speed150r/min. After four molecular distillation, the raw material of alpha-linolenic acid from67.5%purified to82.3%.
超临界流体萃取(supercritical Fluid Extraction)SFE是一种现代分离技术,使用超临界流体作为溶剂。SFE具有处理温度低,萃取挥发性成分效果好,不发生氧化变质的优点与传统的方法相比,可用于色素、香料香精、油脂的萃取等。本实验研究结论结论是超临界CO2萃取胡麻籽油的主要影响因素是萃取压力。萃取温度、萃取时间、CO2流量对实验结果的影响均不显著。经正交实验优选的萃取条件为：CO2流量25L/h；萃取压力30MPa；萃取温度45摄氏度；萃取时间2h。在优选的萃取条件下操作,胡麻籽油的萃取率基本稳定,平均萃取率为36.70%。所得胡麻籽油金黄色、透明。超临界CO.萃取胡麻籽油的萃取率较高,所得的产品较为纯净,不会造成产品污染。因此,避免了溶剂残留和环境污染等问题。
分子蒸馏(Molecular Distillation)又叫短程蒸馏,一种在极高真空、远低于沸点的条件下,利用分子自由程不同的特点完成的液-液分离过程。特别适用于高沸点、热敏性物质的分离,分子蒸馏是在极高真空(1Pa以下)下进行的,而且被蒸馏物受热时间非常短,从而能确保一些较高沸点而又对氧气、热敏感的有机物在蒸馏时不会被氧化、聚合、分解被破坏。应用VKL70型刮膜式分子蒸馏设备对a-亚麻酸进行小试提纯试验,蒸馏温度低,产品不易产生分解变质。并且操作简便,分离效率高,容易实现产业化。应用VKL70型刮膜式分子蒸馏设备对α-亚麻酸进行小试提纯试验,蒸馏温度低,产品不易产生分解变质。并且操作简便,分离效率高,容易实现产业化。试验采用多级操作方式,适宜的分离条件为：蒸馏温度90℃～105℃;操作压力0.3Pa～1.8Pa;进料温度60℃：进料速率90mL/h～100mL/h:刮膜器转速150r/min。经过四级分子蒸馏,可以将原料中的α亚麻酸由原来的67.5%提纯至82.3%。
Flax.(Linum usilalissimiim L) is an annual herb, which likes low temperature and dry climate. It is a long-day crop and widely distributed around the world with5.000years of cultivation history. The study is aimed at extracting oil from flax by Supercritical fluid extraction (SFE) and the molecular distillation(MD).The constituents of distilled oil are analyzed by gas chromatography-mass chromatography. Effects of different extraction conditions on product yield and quality of extracted oil samples are discussed and optimum technology variables are obtained. Thus, theoretical foundations for comprehensive utilization of flax are provided.
Supercritical fluid extraction (supercritical Fluid Extraction) SFE is a modern separation technology, supercritical fluid as a solvent. SFE has a low processing temperature, the effect of extraction of volatile components, oxidative deterioration does not occur compared to the advantages with the conventional method can be used to pigment, fragrance, flavor, grease extraction. The conclusions of this experimental study concluded that supercritical CO2extraction of the main factors of flax seed oil extraction pressure. Extraction temperature, extraction time, CO2flow rate had no significant effects on the experimental results. Orthogonal extraction conditions:the CO2flows25L/h; extraction pressure30MPa; extraction temperature of45degrees Celsius; extraction time2h. Operation, under the extraction conditions in the preferred flax seed oil extraction rate basically stable, the average extraction rate of36.70%. The resulting flax seed oil golden yellow, transparent. Supercritical CO:high extraction flax seed oil extraction rate, the resulting product is more pure and will not cause contamination of the product. Therefore, to avoid the problem of residual solvent and environmental pollution.
Molecular distillation (Molecular Distillation), also known as a short-path distillation, a high vacuum conditions, far below the boiling point of liquid-liquid separation process, completed by the characteristics of the type of the molecular free path. Particularly applicable to high boiling point, separation of the heat-sensitive material, the molecular distillation is carried out under high vacuum (1Pa), and the distillate heating time is very short, so as to ensure a higher boiling point and hot oxygen-sensitive organic matter will not be oxidized during distillation, polymerization, decomposition been destroyed. Wiped film molecular distillation equipment of application VKL70type small scale purification test for alpha-linolenic acid, low temperature distillation, the product is easy to produce the decomposition deterioration. And easy to operate, high separation efficiency, easy to achieve industrialization. Wiped film molecular distillation equipment of application VKL70type small scale purification test for alpha-linolenic acid, low temperature distillation, the product is easy to produce the decomposition deterioration. And easy to operate, high separation efficiency, easy to achieve industrialization. Test uses a multi-stage operation, appropriate separation:distillation temperature of90°C to105°C; the operating pressure0.3Pa to1.8Pa; feed temperature of60°C; feed rate of90ml/h to100mL/h; membrane wiper speed150r/min. After four molecular distillation, the raw material of alpha-linolenic acid from67.5%purified to82.3%.
引文
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[2]Pemilla Johnsson. Phenolic Compounds in Flaxseed[M]. UppsalaTryck:SLU service/ReproUppsala,2004.
[3]MacRae W D, Towers G H N. Biological activities of lignans[J]. Phytochemistry,1984, 23:1207-1220.
[4]Meagher I P, Beecher G R, Flanangan V P, et al. Isolation and Chracterization of the Lignans Isolariciresinol and Pinoresinol in Flaxseed Meal J1. Pro.58 Flax Institute of the United States Fargo, ND, Flax Institute of the United States,2000.
[5]Wang C T, Makela T,Adlererutz H H, et al. Lignans and flavonoids inhibit aromatase enzyme in human preadipoeytes[J]. J Steroid Bioehem Mol Biol,1994,50:20-212.
[6]Johnsson P, Kamal Eldin A, Lundgren L N, et al. HPLC method foranalysis of secoisolariciresinol diglueoside in flaxseeds [J]. J Agric Food Chem,2000,48:5216-5219
[7]联合国粮农组织网站统计数据库,http://faosatat.fao.org/faostat/
[8]Tou J, Thompson L. Exposure to flaxseed of its lignancomponent during different developmental stages influences ratmanunary gland structures[J]. Carcinogenesis,1999,20(9): 1831-1835.
[9]Morton M S, Chan P S F,Cheng C, et al.Lignans and isoflavonoids in plasma and prostatic fluid in inen:samples from Portugal, Hongkong and the United Kingdom [J]. Prostate,1997, 32:22-128.
[10]Lin X, Gingrich J R,Bao W,et al.Effect of flaxseed supplementation on prostatic carcinoma in transgenic mice [J] Urology,2002,60:919-924.
[11]Li D, Yee J A, Thompson L U, et al. Dietary supplementation with secoisolariciresinol diglycoside (SDG)reduces experimental metastasis of melanoma cells in mice [J]. Cancer Letters, 1999,142:91-96.
[12]王惠芳,尉蕊仙.亚麻籽中提取亚麻胶的工艺探讨[J].西部粮油科技,2002(5)：23-24.
[13]罗彤彤,唐燕祥,单齐梅,等.胡麻胶提取新工艺的研究[J].矿冶,2003,12(4)：92-95.
[14]刘洪举.一种亚麻籽油的低温冷榨生产方法：中国,2007100912 64.2[P].2008-10-01.
[15]陈晶,许时婴.亚麻籽油的水酶法提取工艺的研究[J].食品工业科技,2007,28(2)：151-153.
[16]吴素萍,刘敦华.水酶法提取胡麻子油工艺条件的研究[J].中国油脂,2007,32(2)：19-22.
[17]李栋,张振山,汀立君,等.一种超声波辅助提取亚麻油的方法：中国,200710179325.0[P]2008-06-25.
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[3]MacRae W D, Towers G H N. Biological activities of lignans[J]. Phytochemistry,1984, 23:1207-1220.
[4]Meagher I P, Beecher G R, Flanangan V P, et al. Isolation and Chracterization of the Lignans Isolariciresinol and Pinoresinol in Flaxseed Meal J1. Pro.58 Flax Institute of the United States Fargo, ND, Flax Institute of the United States,2000.
[5]Wang C T, Makela T,Adlererutz H H, et al. Lignans and flavonoids inhibit aromatase enzyme in human preadipoeytes[J]. J Steroid Bioehem Mol Biol,1994,50:20-212.
[6]Johnsson P, Kamal Eldin A, Lundgren L N, et al. HPLC method foranalysis of secoisolariciresinol diglueoside in flaxseeds [J]. J Agric Food Chem,2000,48:5216-5219
[7]联合国粮农组织网站统计数据库,http://faosatat.fao.org/faostat/
[8]Tou J, Thompson L. Exposure to flaxseed of its lignancomponent during different developmental stages influences ratmanunary gland structures[J]. Carcinogenesis,1999,20(9): 1831-1835.
[9]Morton M S, Chan P S F,Cheng C, et al.Lignans and isoflavonoids in plasma and prostatic fluid in inen:samples from Portugal, Hongkong and the United Kingdom [J]. Prostate,1997, 32:22-128.
[10]Lin X, Gingrich J R,Bao W,et al.Effect of flaxseed supplementation on prostatic carcinoma in transgenic mice [J] Urology,2002,60:919-924.
[11]Li D, Yee J A, Thompson L U, et al. Dietary supplementation with secoisolariciresinol diglycoside (SDG)reduces experimental metastasis of melanoma cells in mice [J]. Cancer Letters, 1999,142:91-96.
[12]王惠芳,尉蕊仙.亚麻籽中提取亚麻胶的工艺探讨[J].西部粮油科技,2002(5)：23-24.
[13]罗彤彤,唐燕祥,单齐梅,等.胡麻胶提取新工艺的研究[J].矿冶,2003,12(4)：92-95.
[14]刘洪举.一种亚麻籽油的低温冷榨生产方法：中国,2007100912 64.2[P].2008-10-01.
[15]陈晶,许时婴.亚麻籽油的水酶法提取工艺的研究[J].食品工业科技,2007,28(2)：151-153.
[16]吴素萍,刘敦华.水酶法提取胡麻子油工艺条件的研究[J].中国油脂,2007,32(2)：19-22.
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