Preparation method of astragalus seed oil

Abstract

The invention relates to the field of preparation of astragalus seed oil. The invention relates to a preparation method of astragalus seed oil, which comprises the following steps: soaking plump astragalus seeds in water at 40-50 DEG C for 1-2 hours, drying the soaked astragalus seeds at normal temperature for 10-20 hours, crushing the astragalus seeds with dried epidermis, and then adopting a supercritical carbon dioxide extraction method to obtain first batch of astragalus seed oil crude oil; the method comprises the following steps: firstly stir-frying residues obtained after first astragalus seed oil is obtained by adopting a supercritical carbon dioxide extraction method at 185-200 DEG C for 15-30 minutes, then adopting an ultrasonic-assisted extraction method to obtain crude astragalus seed oil of a second batch, and adopting ethyl acetate as an organic solvent; mixing all the astragalus seed crude oil, and then carrying out precipitation, degumming, deacidification and decoloration treatment to remove impurities and free fatty acids and improve the oil purity so as to obtain treated astragalus seed oil; and putting the treated astragalus seed oil into a precipitation tank, extracting from top to bottom in a layering manner, and putting into different containers to obtain astragalus seed oil with different components.

Description

Technical Field

[0001] The present invention relates to the field of preparation of Astragalus seed oil. Background Art

[0002] Astragalus seed oil (essential oil) is a natural oil extracted from Astragalus seeds, which has high nutritional value and potential application value. In terms of regulating metabolism and cardiovascular health, it can assist in reducing blood sugar and improving cardiovascular function; in terms of immune regulation and anti-inflammatory, it can enhance immunity, anti-inflammatory and antioxidant; in terms of liver protection and organ protection, it can protect the liver and kidneys and enhance cardiopulmonary function; in terms of skin care and beauty, it can moisturize and repair the skin and brighten the skin and resist aging; and it also has the effects of warming the middle-jiao and dispelling cold, and detumescence and pain relief. Astragalus seed oil is a composite oil, and its different functions are often realized by different single-chain hydrocarbon oils.

[0003] In the prior art, Astragalus seeds are mostly used for oil extraction together with other oil seeds, and the high nutritional value of Astragalus seeds themselves is damaged during the oil extraction process. There are generally two methods for single Astragalus seeds. The supercritical carbon dioxide extraction method or the ultrasonic-assisted extraction method is used for extraction. The supercritical carbon dioxide extraction method adopts the process conditions: temperature 30°C, pressure 30 MPa, time 2 hours, and the yield can reach 3.31%. This method can efficiently retain the active ingredients in the oil. In the ultrasonic-assisted extraction method (such as Journal of the Chinese Cereals and Oils Association, Vol. 24, No. 11, 2019, Ultrasonic-assisted extraction and fatty acid composition analysis of Astragalus seed oil), the process conditions are: petroleum ether as the extraction agent, liquid-solid ratio 10:1 (mL / g), ultrasonic temperature 60°C, time 25 minutes, power 120 W, and the oil yield is 14.82%. The ultrasonic technology can shorten the extraction time. The above two extraction methods are carried out separately and the oil yield is low. Summary of the Invention

[0004] The technical problem to be solved by the present invention is: how to improve the oil yield of Astragalus seed oil.

[0005] The technical solution adopted by the present invention is: a preparation method of Astragalus seed oil, characterized in that it is carried out according to the following steps: Step 1: Soak plump Astragalus seeds in water at 40-50°C for 1-2 hours, dry the soaked Astragalus seeds at room temperature for 10-20 hours, crush the Astragalus seeds with dry epidermis, and then obtain the first batch of crude Astragalus seed oil by using the supercritical carbon dioxide extraction method; Step 2: First stir-fry the residue after obtaining the first Astragalus seed oil by using the supercritical carbon dioxide extraction method at 185-200°C for 15-30 minutes, and then obtain the secondary batch of crude Astragalus seed oil by using the ultrasonic-assisted extraction method, and the organic solvent is ethyl acetate; Step 3: Mix all the crude Astragalus membranaceus seeds oil and then conduct precipitation, degumming, deacidification, and decolorization treatments to remove impurities and free fatty acids, improve the purity of the oil, and obtain the treated Astragalus membranaceus seeds oil. Step 4: Place the treated Astragalus membranaceus seeds oil in a precipitation tank, extract it layer by layer from top to bottom and place it in different containers to obtain Astragalus membranaceus seeds oil with different components.

[0006] In Step 1, when using the supercritical carbon dioxide extraction method, the extraction conditions are: temperature 35°C, pressure 40 MPa, and time 1.5 hours; in Step 2, the conditions of the ultrasonic-assisted extraction method are: temperature 65°C, time 0.5 hour, and liquid-solid ratio 15 mL / g.

[0007] The precipitation, degumming, deacidification, and decolorization treatments in Step 3 are as follows: Let the second batch of Astragalus membranaceus seeds oil stand for precipitation to remove the sediment at the bottom, then add an aqueous sodium hydroxide solution with a mass percentage concentration of 1 - 1.5%, and the mass of the aqueous sodium hydroxide solution added each time is 10 - 15% of the second batch of Astragalus membranaceus seeds oil, and then centrifuge to obtain the treated Astragalus membranaceus seeds oil.

[0008] In Step 2, after obtaining the crude oil of the second batch of Astragalus membranaceus seeds oil, add 0.1% of its mass of a composite enzyme to the residue of the ultrasonic-assisted extraction method and enzymatically hydrolyze for 2 - 3 h. The composite enzyme is a mixed enzyme of cellulase and Candida antarctica lipase with a mass percentage of (7 - 9):1, and then use the ultrasonic-assisted extraction method again to obtain the crude oil of the last batch of Astragalus membranaceus seeds oil.

[0009] After obtaining the Astragalus membranaceus seeds oil with different components in different layers, centrifuge the Astragalus membranaceus seeds oil of each component again through a centrifuge. On the one hand, concentrate the oil, and on the other hand, separate the oils with different lengths and molecular weights to obtain Astragalus membranaceus seeds oil with different components.

[0010] The beneficial effects of the present invention are: The present invention uses the supercritical carbon dioxide extraction method or the ultrasonic-assisted extraction method to extract Astragalus membranaceus seeds step by step to obtain Astragalus membranaceus seeds oil, which not only improves the oil yield of Astragalus membranaceus seeds oil, but also can obtain higher-quality Astragalus membranaceus seeds oil and ordinary-quality Astragalus membranaceus seeds oil through layered filling. Specific Embodiments

[0011] A method for preparing Astragalus membranaceus seeds oil is carried out according to the following steps: Step 1: Soak the plump Astragalus membranaceus seeds in water at 40 - 50°C for 1 - 2 hours, dry the soaked Astragalus membranaceus seeds at room temperature for 10 - 20 hours, crush the Astragalus membranaceus seeds with dry epidermis, and then use the supercritical carbon dioxide extraction method to obtain the crude oil of the first batch of Astragalus membranaceus seeds oil.

[0012] The particle size of Astragalus membranaceus seeds affects the quality and oil yield of Astragalus membranaceus seed oil. Therefore, it is necessary to screen Astragalus membranaceus seeds to obtain seeds with a suitable particle size to improve the oil yield. The particle sizes of different varieties of Astragalus membranaceus seeds vary greatly, so there is no unified standard. For example, Astragalus membranaceus (soft Astragalus): The seeds are oblate-reniform, with a size of 2.8-3.6 mm in length, 2.5-2.9 mm in width, and 1.0-1.4 mm in thickness; while the diameters of most common varieties of Astragalus membranaceus seeds are between 1-2 mm.

[0013] The moderate temperature soaking of Astragalus membranaceus seeds has an impact on the crude oil yield of the first batch of Astragalus membranaceus seed oil obtained by the subsequent carbon dioxide extraction method. On the one hand, the temperature should ensure that beneficial chemical components are not damaged, and on the other hand, the Astragalus membranaceus seeds can fully absorb water (normal temperature drying after soaking is beneficial for water to enter the interior of the Astragalus membranaceus seeds), causing long-chain degradation. Finally, during supercritical carbon dioxide extraction, a better oil yield can be obtained. Practice shows that soaking in water at 40-50°C for 1-2 hours and then drying at normal temperature can obtain a better oil yield. Compared with directly extracting oil from completely dry Astragalus membranaceus seeds, the oil yield can be increased by more than 30%. However, soaking should not be excessive, otherwise a large amount of hydrocarbon chain scission of Astragalus membranaceus seed oil will occur, reducing the nutritional value.

[0014] In this embodiment, plump Astragalus membranaceus seeds are soaked in water at 45°C for 1.5 hours, and the soaked Astragalus membranaceus seeds are dried at normal temperature for 15 hours. When using the supercritical carbon dioxide extraction method, the extraction conditions are: temperature 35°C, pressure 40 MPa, and time 1.5 hours. This method can extract oil at low temperature and retain active ingredients such as flavonoids and saponins.

[0015] In the supercritical state, supercritical carbon dioxide is brought into contact with the substance to be separated, enabling it to selectively extract components with different polarity sizes, boiling points, and molecular weights in sequence. Of course, the extracts obtained for each pressure range cannot be single, but the conditions can be controlled to obtain a mixture with the best ratio. Then, by means of decompression and temperature increase, the supercritical fluid is turned into ordinary gas, and the substance to be extracted is completely or basically precipitated, thereby achieving the purpose of separation and purification. Therefore, the supercritical fluid carbon dioxide extraction process is composed of extraction and separation. The supercritical carbon dioxide extraction method can be carried out for extraction at a temperature close to room temperature (35-40°C) and under the shroud of carbon dioxide gas, effectively preventing the oxidation and dissipation of heat-sensitive substances. Therefore, all components of the medicinal plant are maintained in the extract, and substances with high boiling points, low volatility, and easy thermal decomposition can be extracted below their boiling point temperatures.

[0016] Step 2: The residue after obtaining the first batch of Astragalus membranaceus seed oil by the supercritical carbon dioxide extraction method is first stir-fried at 185-200°C for 15-30 minutes, and then the ultrasonic-assisted extraction method is used to obtain the crude oil of the second batch of Astragalus membranaceus seed oil, and the organic solvent used is ethyl acetate.

[0017] The conditions of the ultrasonic-assisted extraction method are as follows: temperature 65°C, time 0.5 hour, and liquid-to-solid ratio 15 mL / g.

[0018] The ultrasonic-assisted extraction method is a method that utilizes the cavitation effect, mechanical effect, and thermal effect of ultrasonic waves to accelerate the release, diffusion, and dissolution of effective substances inside cells, significantly improving the extraction efficiency. The main theoretical basis for ultrasonic extraction is the cavitation effect, thermal effect, and mechanical action of ultrasonic waves. When high-energy ultrasonic waves act on a medium, the medium is torn into many small cavities, which instantaneously close and generate an instantaneous pressure of up to several thousand atmospheres, namely the cavitation phenomenon. The bursting of tiny bubbles in ultrasonic cavitation generates an extremely high pressure, enabling the rupture of plant cell walls and the entire organism to be completed instantaneously, shortening the fragmentation time. At the same time, the vibration effect generated by ultrasonic waves enhances the release, diffusion, and dissolution of intracellular substances, thereby significantly improving the extraction efficiency.

[0019] To improve the oil yield, after obtaining the crude oil of the second batch of Astragalus membranaceus seeds, add 0.1% of its mass of a composite enzyme to the residue of the ultrasonic-assisted extraction method and enzymatically hydrolyze for 2 - 3 h. The composite enzyme is a mixed enzyme of cellulase and Candida antarctica lipase with a mass percentage of (7 - 9):1, and then use the ultrasonic-assisted extraction method again to obtain the crude oil of the last batch of Astragalus membranaceus seeds.

[0020] Enzymatic hydrolysis breaks the long molecular chains of the residue under the action of the composite enzyme to form small molecular chains, thereby obtaining a higher oil yield. Through enzymatic hydrolysis, the oil yield can be increased by about 15%.

[0021] Step 3: Mix all the crude Astragalus membranaceus seed oils and then perform precipitation, degumming, and deacidification treatments to remove impurities and free fatty acids, improve the purity of the oil, and obtain the treated Astragalus membranaceus seed oil.

[0022] Regardless of the means of production, the crude Astragalus membranaceus seed oil contains a large amount of impurities. Therefore, it is necessary to carry out treatment to remove impurities. When the crude Astragalus membranaceus seed oil precipitates, the crude oil at the bottom layer and the top layer contain more impurities. Therefore, it is necessary to extract the middle part for degumming and deacidification treatments, while the crude oil at the bottom layer and the top layer of the crude Astragalus membranaceus seed oil need to be placed in the residue of Step 2, enzymatically hydrolyzed with the composite enzyme, and then extracted again.

[0023] Precipitation, degumming, and deacidification are as follows: The second batch of Astragalus seed oil is allowed to stand still to precipitate the bottom sediment (the upper oil phase is taken after static stratification), and then sodium hydroxide aqueous solution is added (using hydration degumming). The mass percentage concentration of the sodium hydroxide aqueous solution is 1 - 1.5%, and the mass of the sodium hydroxide aqueous solution added each time is 10 - 15% of the second batch of Astragalus seed oil. Then, centrifugal separation is carried out to obtain the treated Astragalus seed oil. A centrifugal equipment is used with a rotation speed of 4000 - 6000 rpm and an outlet pressure of 1.5 ± 0.5 kg / cm 3 .

[0024] Step 4: Place the treated Astragalus seed oil in a precipitation tank, and extract it layer by layer from top to bottom and place it in different containers to obtain Astragalus seed oil with different components. Layered extraction can obtain Astragalus seed oil with more excellent and different uses.

[0025] After obtaining Astragalus seed oil with different components in different layers, the Astragalus seed oil of each component is centrifugally separated again by a centrifuge. On the one hand, the oil is concentrated, and on the other hand, oils with different chain lengths of hydrocarbons, aromatics, and molecular weights are separated to obtain Astragalus seed oil with different components.

[0026] In order to obtain Astragalus seed oil with different components more precisely, an extraction process can also be added, and different extraction liquids (such as ethanol, ethyl acetate, etc.) are used for extraction and classification. The ultimate goal is to obtain Astragalus seed oil with components closer to being single.

Claims

1. A preparation method of astragalus seed oil, characterized in that, The steps are as follows: Step 1: Soak the plump Astragalus membranaceus seeds in water at 40 - 50 °C for 1 - 2 hours, dry the soaked Astragalus membranaceus seeds at room temperature for 10 - 20 hours, crush the seeds with dry epidermis, and then obtain the first batch of crude Astragalus membranaceus oil by supercritical carbon dioxide extraction method; Step 2: First, stir-fry the residue after obtaining the first batch of Astragalus membranaceus oil by supercritical carbon dioxide extraction method at 185 - 200 °C for 15 - 30 minutes, and then obtain the second batch of crude Astragalus membranaceus oil by ultrasonic-assisted extraction method. The organic solvent used is ethyl acetate; Step 3: Mix all the crude Astragalus membranaceus oil and conduct precipitation, degumming, and deacidification treatments to remove impurities and free fatty acids, improve the purity of the oil, and obtain the treated Astragalus membranaceus oil; Step 4: Place the treated Astragalus membranaceus oil in a precipitation tank, extract it layer by layer from top to bottom and place it in different containers to obtain Astragalus membranaceus oil with different components.

2. The preparation method of an astragalus seed oil according to claim 1, characterized in that: In Step 1, when using the supercritical carbon dioxide extraction method, the extraction conditions are: temperature 35 °C, pressure 40 MPa, and time 1.5 hours; in Step 2, the conditions of the ultrasonic-assisted extraction method are: temperature 65 °C, time 0.5 hours, and liquid-to-solid ratio 15 mL / g.

3. The preparation method of an astragalus seed oil according to claim 1, characterized in that: The precipitation, degumming, deacidification, and decolorization treatments in Step 3 are as follows: Let the second batch of Astragalus membranaceus oil stand for precipitation to remove the sediment at the bottom, then add sodium hydroxide aqueous solution. The mass percentage concentration of the sodium hydroxide aqueous solution is 1 - 1.5%, and the mass of the sodium hydroxide aqueous solution added each time is 10 - 15% of the second batch of Astragalus membranaceus oil, and then centrifuge to obtain the treated Astragalus membranaceus oil.

4. The preparation method of an astragalus seed oil according to claim 1, wherein: In Step 2, after obtaining the second batch of crude Astragalus membranaceus oil, add 0.1% of its mass of composite enzyme to the residue of the ultrasonic-assisted extraction method and enzymolyze for 2 - 3 h. The composite enzyme is a mixed enzyme of cellulase and Candida antarctica lipase with a mass percentage of (7 - 9):1, and then use the ultrasonic-assisted extraction method again to obtain the last batch of crude Astragalus membranaceus oil.

5. The preparation method of an astragalus seed oil according to claim 1, characterized in that: After crushing the seeds with dry epidermis, add antioxidant vitamin E, and then use the supercritical carbon dioxide extraction method to obtain the first batch of crude Astragalus membranaceus oil. The antioxidant vitamin E accounts for 0.05% - 0.1% of the mass of Astragalus membranaceus seeds.

6. The preparation method of an astragalus seed oil according to claim 1, wherein: After obtaining Astragalus membranaceus oil with different components in different layers, centrifuge each component of Astragalus membranaceus oil again by a centrifuge. On the one hand, concentrate the oil, and on the other hand, separate the oils with different chain lengths of hydrocarbons, different types of aromatic hydrocarbons, and molecular weights to obtain Astragalus membranaceus oil with different components.