Preparation process of peony seed oil

Abstract

The invention relates to a preparation process of peony seed oil, and belongs to the technical field of oil extraction. The invention provides a preparation process of peony seed oil, which comprises the following steps: performing heat treatment, drying and crushing on peony seeds subjected to impurity removal to obtain peony seed powder; performing supercritical CO2 extraction on the obtained peony seed powder to obtain crude peony seed oil; carrying out deacidification treatment on the obtained crude peony seed oil to obtain deacidified peony seed oil; and filtering the deacidified peony seed oil to obtain the peony seed oil. According to the invention, the three technologies of microwave pretreatment, supercritical CO2 extraction and molecular distillation deacidification are creatively combined to form an integrated preparation process, and parameters of each process link are accurately set and optimized, so that the stability of the process and the consistency of product quality are favorably improved.

Description

Technical Field

[0001] The invention relates to the technical field of oil extraction, in particular to a preparation process of peony seed oil. Background Art

[0002] Peony seed oil is a high-quality vegetable oil, rich in unsaturated fatty acids, vitamins and other nutrients, with high nutritional value and health benefits. In order to obtain high-quality peony seed oil, traditional extraction processes usually use physical pressing, solvent extraction and other methods for extraction. The extracted peony seed oil contains some impurities and undesirable components, such as free fatty acids, pigments, odorous substances, etc., which need to be treated by refining process to improve the quality and stability of peony seed oil. The traditional refining process is to remove phospholipids and other colloid substances in peony seed oil by degumming to prevent the oil from oxidation, hydrolysis and other reactions during storage; then reduce the free fatty acid content in peony seed oil by deacidification; then decolorize to remove the pigment in peony seed oil, make the oil color lighter, and improve the appearance quality of the oil; finally, remove the odorous substances in peony seed oil by deodorization, such as aldehydes, ketones, alcohols, etc., to improve the flavor and quality of the oil. This refining technology is relatively mature, and the quality of peony seed oil after refining is significantly improved, with light color, high transparency, no odor, good stability, and easy storage and transportation.

[0003] During the extraction process of peony seed oil obtained by existing methods, some methods have low oil yields, which causes a certain degree of damage to the nutritional components of the oil; and some nutrients, such as vitamins and sterols, are lost during the refining process. At the same time, the refining process is relatively complicated and requires a certain amount of energy and chemical reagents, which does not conform to the concept of low-carbon and environmental protection. Summary of the invention

[0004] The purpose of the invention is to overcome the shortcomings of the prior art and provide a peony seed oil preparation process with low energy consumption, environmental protection and high purity.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] The present invention provides a preparation process of peony seed oil, comprising the following steps:

[0007] (1) heat-treating the peony seeds after impurity removal, drying, and crushing to obtain peony seed powder;

[0008] (2) subjecting the peony seed powder obtained in step (1) to supercritical CO 2 Extraction to obtain crude peony seed oil;

[0009] (3) deacidifying the crude peony seed oil obtained in step (2) to obtain deacidified peony seed oil;

[0010] (4) filtering the deacidified peony seed oil obtained in step (3) to obtain peony seed oil.

[0011] The present invention creatively proposes to combine microwave pretreatment, supercritical CO 2 The three technologies of extraction and molecular distillation deacidification are combined to form an integrated preparation process, and the parameters of each process link are precisely set and optimized, which is conducive to improving the stability of the process and the consistency of product quality. At the same time, the synergy of the above technologies and precise parameter control can maximize the retention of heat-sensitive nutrients in peony seed oil, increase the content of unsaturated fatty acids and antioxidant properties, enhance the stability of the product, and have low acidity and high quality, which better meets consumers' demand for high-quality edible oil.

[0012] As a preferred embodiment of the preparation process of the present invention, in step (1), the heat treatment is to place the peony seeds after impurities removal on a microwave equipment conveyor belt and use a microwave equipment for heat treatment. When the peony seeds are subjected to microwave treatment, the peony seeds absorb microwave energy, resulting in an increase in the temperature of the raw materials, causing the water in the peony seeds to gradually evaporate and increase its internal pressure. In addition, the release of steam can destroy the peony seed cell membrane to a certain extent, thereby increasing the cell gap, promoting the formation of oil channels, expanding the oil outflow channel, and increasing the oil yield. The advanced high-resolution electron microscope is used to analyze the cell structure of the peony seeds after microwave treatment. This microwave treatment can accurately destroy the peony seed cell membrane, increase the cell gap by 20-50%, and promote the formation of oil channels.

[0013] As a preferred embodiment of the preparation process of the present invention, in step (1), the condition of the heat treatment is to use a microwave device with a microwave power of 2-6kW for 1-5min. Under the preferred parameter range, the peony seed oil prepared by the preparation process of the present invention has a higher oil yield. When the microwave power is too large or the treatment time is too long, it is easy to cause the unsaturated fatty acids in the peony seed oil to be more easily oxidized, affecting the color and transparency, and may destroy some heat-sensitive nutrients in the peony seed oil, such as vitamin E, phytosterols, etc.; when the microwave power is too small or the treatment time is too short, it is not possible to effectively destroy the cell structure of the peony seeds, making it difficult to fully release the oil, thereby reducing the extraction rate of the oil.

[0014] As a preferred embodiment of the preparation process of the present invention, in step (1), the heat treatment condition is to use a microwave device with a microwave power of 3-5 kW for 2-3 min.

[0015] As a preferred embodiment of the preparation process of the present invention, in step (1), the heat treatment condition is to use a microwave device with a microwave power of 4 kW for 2-3 minutes.

[0016] As a preferred embodiment of the preparation process of the present invention, in step (1), the heat treatment condition is to use a microwave device with a microwave power of 5 kW for 1 min.

[0017] As a preferred embodiment of the preparation process of the present invention, in step (1), the drying is performed at 42-48° C. until the moisture content is 7-10%.

[0018] As a preferred embodiment of the preparation process of the present invention, in step (1), the drying is performed at 43-45° C. to a moisture content of 8-9%.

[0019] As a preferred embodiment of the preparation process of the present invention, in step (2), the supercritical CO 2 The extraction includes discontinuous cycle high pressure extraction and separation steps. The discontinuous extraction method selected in the present invention can give the internal structure of the peony seed powder a short recovery time, so that the supercritical CO 2 It can contact with oil more effectively at different time intervals. Through multiple cycles, it can improve the utilization rate and production efficiency of equipment while ensuring the extraction effect.

[0020] As a preferred embodiment of the preparation process of the present invention, in step (2), the supercritical CO 2 The conditions of discontinuous high-pressure extraction in the extraction process are 30-40℃, 20-30MPa, and the extraction is stopped for 0.1h after each 0.3h of extraction, and then stopped for 0.1h after another 0.3h of extraction, and the cycle is repeated until the total extraction time is 0.6-2.1h and the extraction is completed. In the extraction process, the pressure has an effect on the supercritical CO 2 The density and solubility of CO are greatly affected. 2 The density of the supercritical CO increases, and its ability to dissolve oils and fats increases, thereby increasing the extraction rate. As the temperature rises, the molecular motion intensifies, and the oils and fats in the supercritical CO 2 However, too high a temperature may cause some components in the oil to undergo oxidation, decomposition and other adverse reactions, affecting the quality and nutritional value of the oil; on the contrary, too low a temperature may cause CO 2 The solubility of the supercritical CO is reduced, and the extraction rate is affected. In addition, the present invention selects a gradient temperature change method to increase the extraction temperature from 30°C to 40°C, which can make the supercritical CO 2 The oil in the peony seed powder is gradually extracted at different temperatures to adapt to the differences in oil distribution and structure inside the peony seed powder and improve the extraction effect.

[0021] As a preferred embodiment of the preparation process of the present invention, in step (2), the supercritical CO 2The conditions of discontinuous cycle high-pressure extraction in the extraction are 30-40°C and 25-28MPa. The extraction is stopped for 0.1h after each 0.3h of extraction, and then stopped for 0.1h after another 0.3h of extraction. The cycle is repeated until the total extraction time is 0.9-1.5h and the extraction is completed.

[0022] As a preferred embodiment of the preparation process of the present invention, in step (2), the supercritical CO 2 The separation in the extraction includes primary separation and secondary separation. The conditions of the primary separation are 8-9MPa and 36-38°C, and the conditions of the secondary separation are 3-4MPa and 26-28°C.

[0023] As a preferred embodiment of the preparation process of the present invention, in step (2), the supercritical CO 2 The separation in the extraction includes primary separation and secondary separation. The conditions of the primary separation are 8-9 MPa and 37°C, and the conditions of the secondary separation are 3-4 MPa and 27°C.

[0024] As a preferred embodiment of the preparation process of the present invention, in step (3), the deacidification treatment is carried out at a pressure of 0.1-5Pa.

[0025] As a preferred embodiment of the preparation process of the present invention, in step (3), the feeding rate of the peony seed oil obtained in step (2) during the deacidification treatment is 1-5 L / min.

[0026] As a preferred embodiment of the preparation process of the present invention, in step (3), the feeding rate of the peony seed oil obtained in step (2) during the deacidification treatment is 2-4 L / min.

[0027] As a preferred embodiment of the preparation process of the present invention, in step (3), the feeding rate of the peony seed oil obtained in step (2) during the deacidification treatment is 3 L / min.

[0028] As a preferred embodiment of the preparation process of the present invention, in step (3), the deacidification treatment is completed in a molecular distillation device. The free fatty acids and other small molecular substances in the peony seed oil are light in weight and have a relatively large molecular motion mean free path under high vacuum conditions, so they can diffuse rapidly and be easily separated from the mixture, while the main component oil molecules in the peony seed oil are relatively large and heavy in weight, and their mean free path is small, so they will remain in a specific area of ​​the distillation device. During the deacidification process, the separated free fatty acids and other substances enter the high-efficiency condenser through a special condensation pipeline. The condenser is maintained at a relatively low temperature, usually at 5-15°C, to ensure that the free fatty acids and other substances are quickly cooled and condensed and collected. The peony seed oil after the deacidification treatment flows out from a specific outlet of the molecular distillation device. The present invention can achieve efficient deacidification of the peony seed oil by accurately controlling the vacuum degree, temperature, film scraping speed and feeding speed during the molecular distillation process, improve the quality and stability of the product, and retain the heat-sensitive nutrients in the peony seed oil to the greatest extent.

[0029] As a preferred embodiment of the preparation process of the present invention, in step (3), the scraping speed in the deacidification treatment is 5-15r / min. The present invention creatively adds a scraper to the deacidification treatment, which can evenly distribute the peony seed oil on the heating surface to form a thin film to increase the evaporation area of ​​the material and improve the separation efficiency. The selection of the scraping speed should comprehensively consider the properties of the material, the performance of the equipment and the requirements of the separation effect. If the scraping speed is too low, the material cannot be evenly distributed on the heating surface, which may cause local overheating or material accumulation, affecting the separation efficiency and product quality; if the scraping speed is too high, it may generate excessive shear force, causing the heat-sensitive components in the material to be destroyed, and also increase the energy consumption and wear of the equipment.

[0030] As a preferred embodiment of the preparation process of the present invention, in step (3), the scraping speed in the deacidification treatment is 8-12 r / min.

[0031] As a preferred embodiment of the preparation process of the present invention, in step (3), the scraping speed in the deacidification treatment is 10 r / min.

[0032] As a preferred embodiment of the preparation process of the present invention, in step (3), the scraping film material in the deacidification treatment is a ceramic material. The scraping film material of the present invention is preferably a ceramic material because it has good high temperature resistance and can withstand the high temperature environment during the molecular distillation process without softening or deformation. In addition, it will not react with the components in the peony seed oil, and can better distribute the peony seed oil evenly on the heating surface to improve the separation efficiency.

[0033] As a preferred embodiment of the preparation process of the present invention, in step (3), the heating temperature of the molecular distillation is 150-200°C.

[0034] As a preferred embodiment of the preparation process of the present invention, in step (3), the heating temperature of the molecular distillation is 150-180°C.

[0035] As a preferred embodiment of the preparation process of the present invention, in step (3), the heating temperature of the molecular distillation is 150-170°C.

[0036] As a preferred embodiment of the preparation process of the present invention, in step (3), the heating temperature of the molecular distillation is 150-160°C.

[0037] As a preferred embodiment of the preparation process of the present invention, in step (3), the heating temperature of the molecular distillation is 150°C.

[0038] As a preferred embodiment of the preparation process of the present invention, in step (4), the filtration pressure is 0.2-0.4 MPa.

[0039] As a preferred embodiment of the preparation process of the present invention, in step (4), the filtration pressure is 0.25-0.35 MPa.

[0040] As a preferred embodiment of the preparation process of the present invention, in step (4), the filtration pressure is 0.3 MPa.

[0041] Compared with the prior art, the present invention has the following beneficial effects:

[0042] 1. The present invention creatively proposes to combine microwave pretreatment and supercritical CO 2 The three technologies of extraction and molecular distillation deacidification are combined to form an integrated preparation process, and the parameters of each process link are precisely set and optimized, which is conducive to improving the stability of the process and the consistency of product quality. At the same time, the synergy of the above technologies and precise parameter control can maximize the retention of heat-sensitive nutrients in peony seed oil, increase the content of unsaturated fatty acids and antioxidant properties, enhance the stability of the product, and have low acidity and high quality, which better meets consumers' demand for high-quality edible oil.

[0043] 2. The preparation process of the present invention has significant environmental advantages, CO 2 It can be recycled, and the wastewater and waste gas emissions are almost zero. Compared with traditional methods, there is no chemical reagent and solvent residue. It conforms to the current concept of green development and provides technical support for sustainable development. At the same time, it provides reference significance for the efficient extraction and refining of other vegetable oils. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 This is a comparison diagram of the appearance of different peony seed oils in Effect Example 1 of the present invention;

[0045] Figure 2 This is a graph showing the unsaturated fatty acid detection results of different peony seed oils in Effect Example 1 of the present invention;

[0046] Figure 3 This is the effect of different treatment processes on peony seed cells in Effect Example 1 of the present invention. DETAILED DESCRIPTION

[0047] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0048] Unless otherwise specified, the reagents and consumables used in the following experimental examples can be obtained through commercial channels.

[0049] Commercially available peony seed oil was purchased from Hubei Kangchun Spice Co., Ltd.

[0050] Example 1

[0051] This embodiment provides a preparation process of peony seed oil, comprising the following steps:

[0052] S1, using efficient impurity removal equipment to remove impurities from peony seeds, washing the peony seeds with pure water to obtain impurity-removed peony seeds;

[0053] S2, evenly spread the peony seeds after impurity removal obtained in step S1 on the conveyor belt of the microwave equipment, start the microwave equipment, set the parameters to 3kW, heat treat for 3min, transfer to a dryer, dry at 45°C to a moisture content of 9%, and obtain peony seed powder after crushing;

[0054] S3, put the peony seed powder obtained in step S2 into the extraction kettle, seal the kettle cover, and turn on the CO 2 Gas cylinders, making CO 2 The gas is cooled to liquid through an efficient cold box and pressurized to an extraction pressure of 25 MPa by a high-pressure pump. The initial extraction temperature is set to 30°C, and the extraction temperature gradient is set to 40°C to make the liquid CO 2 Fully contact with peony seed powder, extract for 0.3h and then stop for 0.1h, repeat the cycle, when the total extraction time is 0.9h, pass the obtained product into a primary separation kettle with a pressure set at 8MPa and a temperature set at 36°C, and then enter a secondary separation kettle with a pressure set at 3MPa and a temperature set at 26°C to separate and obtain crude peony seed oil;

[0055] S4, the crude peony seed oil obtained in step S3 is transferred to a molecular distillation apparatus at a feeding rate of 3L / min, the molecular distillation apparatus is set to a high vacuum state, a ceramic film scraper is installed on the inner wall of the distiller, the film scraper rotates at a speed of 10r / min, the heating temperature is set to 150°C, and the condenser temperature is maintained at 10±2°C, so that the crude peony seed oil is deacidified, and the peony seed oil after deacidification flows out from a specific outlet;

[0056] S5. Transfer the deacidified peony seed oil obtained in step S4 into a plate-and-frame filter and filter under a pressure of 0.3 MPa to obtain peony seed oil.

[0057] Example 2

[0058] This embodiment provides a preparation process of peony seed oil, comprising the following steps:

[0059] S1, using efficient impurity removal equipment to remove impurities from peony seeds, washing the peony seeds with pure water to obtain impurity-removed peony seeds;

[0060] S2, the peony seeds after impurity removal obtained in step S1 are evenly spread on the conveyor belt of the microwave equipment, the microwave equipment is started, the parameters are set to 4kW, the heat treatment is carried out for 2min, and the seeds are transferred to a dryer and dried at 48°C to a moisture content of 8%, and the peony seed powder is obtained after crushing;

[0061] S3, put the peony seed powder obtained in step S2 into the extraction kettle, seal the kettle cover, and turn on the CO 2 Gas cylinders, making CO 2 The gas is cooled to liquid through an efficient cold box and pressurized to an extraction pressure of 28 MPa by a high-pressure pump. The initial extraction temperature is set to 30 °C, and the extraction temperature gradient is set to 40 °C to make the liquid CO 2 Fully contact with peony seed powder, extract for 0.3h and then stop for 0.1h, repeat the cycle, when the total extraction time is 1.5h, pass the obtained product into a primary separation kettle with a pressure set at 9MPa and a temperature set at 38°C, and then enter a secondary separation kettle with a pressure set at 4MPa and a temperature set at 28°C to separate and obtain crude peony seed oil;

[0062] S4, the crude peony seed oil obtained in step S3 is transferred to a molecular distillation apparatus at a feeding rate of 2L / min, the molecular distillation apparatus is set to a high vacuum state, a ceramic scraper is installed on the inner wall of the distiller, the scraper rotates at a speed of 8r / min, the heating temperature is set to 170°C, and the condenser temperature is maintained at 10±2°C, so that the crude peony seed oil is deacidified, and the deacidified peony seed oil flows out from a specific outlet;

[0063] S5. Transfer the deacidified peony seed oil obtained in step S4 into a plate-and-frame filter and filter at a pressure of 0.25 MPa to obtain peony seed oil.

[0064] Example 3

[0065] This embodiment provides a preparation process of peony seed oil, comprising the following steps:

[0066] S1, using efficient impurity removal equipment to remove impurities from peony seeds, washing the peony seeds with pure water to obtain impurity-removed peony seeds;

[0067] S2, the peony seeds after impurity removal obtained in step S1 are evenly spread on the conveyor belt of the microwave equipment, the microwave equipment is started, the parameter is set to 5kW, the heat treatment is 1min, and the seeds are transferred to a dryer and dried at 42°C to a moisture content of 7%, and the peony seed powder is obtained after crushing;

[0068] S3, put the peony seed powder obtained in step S2 into the extraction kettle, seal the kettle cover, and turn on the CO 2 Gas cylinders, making CO 2 The gas is cooled to liquid through an efficient cold box and pressurized to an extraction pressure of 30 MPa by a high-pressure pump. The initial extraction temperature is adjusted to 30 °C, and the extraction temperature gradient is set to 40 °C to make the liquid CO 2 Fully contact with peony seed powder, extract for 0.3h and then stop for 0.1h, repeat the cycle, when the total extraction time is 0.6h, pass the obtained product into a primary separation kettle with a pressure set at 8MPa and a temperature set at 37°C, and then enter a secondary separation kettle with a pressure set at 3MPa and a temperature set at 27°C to separate and obtain crude peony seed oil;

[0069] S4, the crude peony seed oil obtained in step S3 is transferred to a molecular distillation apparatus at a feeding rate of 4L / min, the molecular distillation apparatus is set to a high vacuum state, a ceramic film scraper is installed on the inner wall of the distiller, the film scraper rotates at a speed of 12r / min, the heating temperature is set to 180°C, and the condenser temperature is maintained at 10±2°C, so that the crude peony seed oil is deacidified, and the deacidified peony seed oil flows out from a specific outlet;

[0070] S5. Transfer the deacidified peony seed oil obtained in step S4 into a plate-and-frame filter and filter at a pressure of 0.35 MPa to obtain peony seed oil.

[0071] Example 4

[0072] This embodiment provides a preparation process of peony seed oil, comprising the following steps:

[0073] S1, using efficient impurity removal equipment to remove impurities from peony seeds, washing the peony seeds with pure water to obtain impurity-removed peony seeds;

[0074] S2, the peony seeds after impurity removal obtained in step S1 are evenly spread on the conveyor belt of the microwave equipment, the microwave equipment is started, the parameter is set to 2kW, the heat treatment is 5min, the peony seeds are transferred to the dryer, and the water content is 10% at 42°C, and the peony seed powder is obtained after crushing;

[0075] S3, put the peony seed powder obtained in step S2 into the extraction kettle, seal the kettle cover, and turn on the CO 2 Gas cylinders, making CO 2 The gas is cooled to liquid through an efficient cold box and pressurized to an extraction pressure of 26 MPa by a high-pressure pump. The initial extraction temperature is set to 30 °C, and the extraction temperature gradient is set to 40 °C to make the liquid CO 2 Fully contact with peony seed powder, extract for 0.3h and then stop for 0.1h, repeat the cycle, when the total extraction time is 2.1h, pass the obtained product into a primary separation kettle with a pressure set at 9MPa and a temperature set at 37°C, and then enter a secondary separation kettle with a pressure set at 4MPa and a temperature set at 27°C to separate and obtain crude peony seed oil;

[0076] S4, the crude peony seed oil obtained in step S3 is transferred to a molecular distillation apparatus at a feeding rate of 1.5L / min, the molecular distillation apparatus is set to a high vacuum state, a ceramic film scraper is installed on the inner wall of the distiller, the film scraper rotates at a speed of 5r / min, the heating temperature is set to 200°C, and the condenser temperature is maintained at 10±2°C, so that the crude peony seed oil is deacidified, and the deacidified peony seed oil flows out from a specific outlet;

[0077] S5. Transfer the deacidified peony seed oil obtained in step S4 into a plate-and-frame filter and filter under a pressure of 0.2 MPa to obtain peony seed oil.

[0078] Example 5

[0079] This embodiment provides a preparation process of peony seed oil, comprising the following steps:

[0080] S1, using efficient impurity removal equipment to remove impurities from peony seeds, washing the peony seeds with pure water to obtain impurity-removed peony seeds;

[0081] S2, the peony seeds after impurity removal obtained in step S1 are evenly spread on the conveyor belt of the microwave equipment, the microwave equipment is started, the parameters are set to 6kW, the heat treatment is 1min, and the seeds are transferred to a dryer and dried at 43°C to a moisture content of 10%, and the peony seed powder is obtained after crushing;

[0082] S3, put the peony seed powder obtained in step S2 into the extraction kettle, seal the kettle cover, and turn on the CO 2 Gas cylinders, making CO 2The gas is cooled to liquid through an efficient cold box and pressurized to an extraction pressure of 20 MPa by a high-pressure pump. The initial extraction temperature is adjusted to 30°C, and the extraction temperature gradient is set to 40°C to make the liquid CO 2 Fully contact with peony seed powder, extract for 0.3h and then stop for 0.1h, repeat the cycle, when the total extraction time is 2.1h, pass the obtained product into a primary separation kettle with a pressure set at 9MPa and a temperature set at 37°C, and then enter a secondary separation kettle with a pressure set at 4MPa and a temperature set at 27°C to separate and obtain crude peony seed oil;

[0083] S4, the crude peony seed oil obtained in step S3 is transferred to a molecular distillation apparatus at a feeding rate of 1.5L / min, the molecular distillation apparatus is set to a high vacuum state, a ceramic film scraper is installed on the inner wall of the distiller, the film scraper rotates at a speed of 15r / min, the heating temperature is set to 160°C, and the condenser temperature is maintained at 10±2°C, so that the crude peony seed oil is deacidified, and the deacidified peony seed oil flows out from a specific outlet;

[0084] S5. Transfer the deacidified peony seed oil obtained in step S4 into a plate-and-frame filter and filter at a pressure of 0.4 MPa to obtain peony seed oil.

[0085] Comparative Example 1

[0086] This comparative example provides a preparation process of peony seed oil, which is similar to that of Example 1, except that:

[0087] In step S2, the peony seeds after impurities removal are not subjected to microwave treatment, but are directly transferred to a dryer for drying, and the remaining steps and parameter conditions remain unchanged.

[0088] Comparative Example 2

[0089] This comparative example provides a preparation process of peony seed oil, which is similar to that of Example 1, except that:

[0090] In step S3, the extraction pressure is set to 36 MPa, the total extraction time is set to 3 h, and the remaining steps and parameter conditions remain unchanged.

[0091] Comparative Example 3

[0092] This comparative example provides a preparation process of peony seed oil, which is similar to that of Example 1, except that:

[0093] In step S3, the extraction pressure is set to 25 MPa, the continuous extraction time is 0.9 h, and the remaining steps and parameter conditions remain unchanged.

[0094] Comparative Example 4

[0095] This comparative example provides a preparation process of peony seed oil, which is similar to that of Example 1, except that:

[0096] In step S4, the material feeding speed is set to 6 L / min, the rotation speed of the scraper is set to 30 r / min, and the remaining steps and parameter conditions remain unchanged.

[0097] Comparative Example 5

[0098] This comparative example provides a preparation process of peony seed oil, which is similar to that of Example 1, except that:

[0099] In step S4, the material feeding speed is set to 0.5 L / min, the rotation speed of the scraper is set to 1 r / min, and the remaining steps and parameter conditions remain unchanged.

[0100] Comparative Example 6

[0101] This comparative example provides a preparation process of peony seed oil, which is similar to that of Example 1, except that:

[0102] In step S4, the material of the film scraper is polytetrafluoroethylene, and the remaining steps and parameter conditions remain unchanged.

[0103] Comparative Example 7

[0104] This comparative example provides a preparation process of peony seed oil, and the preparation process is a traditional cold pressing process. Referring to the common cold pressing operation specifications of the industry, the peony seeds are first screened to remove impurities, deflated particles and other unqualified particles. Then, in a low temperature environment (usually controlled below 20°C), a hydraulic oil press is used for squeezing. The screened peony seeds are slowly placed in the oil press, and pressure is gradually applied, and the pressure is slowly increased from a small value to a suitable pressure to ensure the oil output efficiency and not to make the oil temperature too high. During the squeezing process, the outflowing oil is collected and filtered through a preliminary filter to remove solid impurities therein. Subsequently, the peony seed oil after preliminary filtration is centrifuged to further remove the fine impurities remaining in the oil. Finally, a low-temperature fine filtration device is used to filter the peony seed oil again under low temperature conditions using a fine filter, so as to prepare relatively pure peony seed oil.

[0105] Effect Example 1

[0106] 1. Observe the appearance of the peony seed oil obtained in Example 3 and the peony seed oil obtained in Comparative Example 7. Figure 1 .

[0107] like Figure 1 As shown, the peony seed oil obtained in Comparative Example 7 is dark in color and easily deteriorates, while the peony seed oil obtained in Example 1 is bright golden in color, clear and transparent, and has better stability.

[0108] 2. Liquid chromatography was performed on the peony seed oil obtained in Example 3 and commercially available peony seed oil. The results are shown in Figure 2 .

[0109] like Figure 2 As shown, compared with the commercially available peony seed oil, the peony seed oil obtained in Example 3 has higher contents of linolenic acid, linoleic acid and oleic acid, and the area ratio of the response peaks is approximately linolenic acid: linoleic acid: oleic acid = 1.75:1.75:1, indicating that the preparation process of the present invention can extract peony seed oil with a higher content of unsaturated fatty acids.

[0110] 3. The cell structure of the peony seed powder obtained in step S2 of Example 1 and Comparative Example 6 was observed by electron microscope. Figure 1 .

[0111] like Figure 3 As shown, after microwave treatment, the cell membrane of peony seed powder ruptures and the cell gap increases, which promotes the formation of oil channels, expands the oil outflow channel, and increases the oil yield.

[0112] Effect Example 2

[0113] 1. Oil yield

[0114] Principle: The oil yield reflects the efficiency of obtaining oil from peony seeds. By accurately measuring the quality of raw materials and obtained oil, the impact of different processes on oil extraction can be intuitively reflected.

[0115] Instruments and materials: analytical balance (with an accuracy of 0.001g to ensure accurate mass measurement), drying oven (used to remove oil and moisture to ensure measurement accuracy), extraction device (equipped according to the corresponding process, such as supercritical CO 2 Extraction or cold pressing equipment), filtering device (to remove impurities and ensure the purity of oil).

[0116] step:

[0117] Accurately weigh the peony seed raw material mass (m 1 ), record the data.

[0118] Peony seed oil is extracted according to the process, and filtered after extraction to remove impurities.

[0119] Place the filtered peony seed oil in a weighed dry container (mass m 2 ), put it into a 105℃ drying oven until constant weight is reached, and weigh it after cooling (total mass is m 3 ).

[0120] Using the formula: Oil yield (%) = (m 3 -m 2 ) / m 1 ×100% to calculate the oil yield.

[0121] 2. α-linolenic acid extraction rate

[0122] Principle: Gas chromatography (GC) uses the unique retention time of α-linolenic acid on a specific chromatographic column, compares it with the standard, and combines it with the peak area normalization method to accurately calculate its content and extraction rate in peony seed oil.

[0123] Instruments and reagents: gas chromatograph equipped with a hydrogen flame ionization detector (FID), HP-88 capillary column (good for separation of fatty acids), n-hexane (chromatographic grade, to ensure sample solubility purity), and α-linolenic acid standard.

[0124] step:

[0125] Sample preparation: Accurately weigh about 0.1 g of peony seed oil sample, place it in a 10 mL volumetric flask, and dilute to volume with n-hexane to obtain a sample solution.

[0126] Drawing of standard curve: prepare standard solutions of α-linolenic acid of different concentrations, analyze them by gas chromatography, and draw the standard curve with concentration as the horizontal axis and peak area as the vertical axis.

[0127] Sample determination: Take an appropriate amount of sample solution and inject it into the gas chromatograph. Analyze it under the set conditions (injection port 250°C, detector 280°C, column temperature program). According to the peak area, the concentration (C) is obtained from the standard curve. The extraction rate is calculated by the formula α-linolenic acid extraction rate (%) = (C×V×M) / (m×1000)×100% (V is the volume of the sample solution, M is the relative molecular mass of α-linolenic acid, and m is the sample mass).

[0128] 3. Acid Value

[0129] Principle: Based on the principle of acid-base neutralization, the free fatty acids in peony seed oil are titrated with potassium hydroxide standard solution. Phenolphthalein is used as an indicator. The acid value is calculated by the amount of potassium hydroxide consumed, which reflects the freshness and quality of the oil.

[0130] Instruments and reagents: 50mL burette (for accurately measuring the volume of titrant), 250mL conical flask (for reaction), 0.1mol / L potassium hydroxide standard solution, phenolphthalein indicator, neutral ethanol-ether mixed solvent (1:1, volume ratio, for dissolving oils and fats).

[0131] step:

[0132] Accurately weigh 3-5 g of peony seed oil sample into a 250 mL conical flask, add 50-70 mL of neutral ethanol-ether mixed solvent, and shake to dissolve.

[0133] Add 2-3 drops of phenolphthalein indicator and titrate with 0.1 mol / L potassium hydroxide standard solution until the solution turns pink and does not fade within 30 seconds. Record the volume of potassium hydroxide solution consumed (V).

[0134] The acid value was calculated using the formula acid value (mg / g) = (V x C x 56.1) / m (V is the volume of the consumed potassium hydroxide solution, C is the potassium hydroxide concentration, 56.1 is the molar mass of potassium hydroxide, and m is the sample mass).

[0135] 4. Peroxide Value

[0136] Principle: The peroxide in the oil reacts with potassium iodide to generate iodine, which is then titrated with a standard sodium thiosulfate solution. The peroxide value is calculated based on the amount of sodium thiosulfate consumed, reflecting the degree of oxidation of the oil.

[0137] Instruments and reagents: 250mL iodine volume flask (providing reaction environment), 50mL burette (accurately measuring titrant), 0.01mol / L sodium thiosulfate standard solution, saturated potassium iodide solution, starch indicator, glacial acetic acid-chloroform mixed solvent (3:2, volume ratio, used to dissolve oil and promote reaction).

[0138] step:

[0139] Accurately weigh 2-3 g of peony seed oil sample into a 250 mL iodine volumetric flask, add 30 mL of glacial acetic acid-chloroform mixed solvent, and shake to dissolve.

[0140] Add 1.0 mL of saturated potassium iodide solution, plug the bottle tightly, and place it in a dark place for 3 min.

[0141] After taking it out, add 75mL of water and immediately titrate it with 0.01mol / L sodium thiosulfate standard solution until it turns light yellow. Add 1mL of starch indicator and continue titrating until the blue color disappears. Record the volume (V) of sodium thiosulfate solution consumed.

[0142] The peroxide value was calculated by the formula peroxide value (mmol / kg) = (V x C x 1000) / m (V is the volume of the consumed sodium thiosulfate solution, C is the sodium thiosulfate concentration, and m is the sample mass).

[0143] 5. Tocopherol Content

[0144] Principle: High performance liquid chromatography (HPLC) uses the difference in distribution coefficient of tocopherol on a reverse phase chromatographic column to achieve separation, and quantitative analysis is performed by comparing the retention time and peak area with those of the standard to determine its content in peony seed oil.

[0145] Instruments and reagents: High performance liquid chromatography equipped with UV detector, C18 reverse phase column (suitable for tocopherol separation), methanol (chromatographic grade, as mobile phase), tocopherol standards (α-tocopherol, β-tocopherol, γ-tocopherol, δ-tocopherol, etc.).

[0146] step:

[0147] Sample preparation: Accurately weigh 0.5 g of peony seed oil sample, place it in a 10 mL volumetric flask, dissolve it in methanol and make up to volume, filter the solution through a 0.45 μm filter membrane and inject it into the injection bottle.

[0148] Standard curve drawing: Prepare tocopherol standard mixed solutions of different concentrations, analyze them by high performance liquid chromatography, and draw a standard curve with concentration as the horizontal axis and peak area as the vertical axis.

[0149] Sample determination: Under the set conditions (mobile phase methanol-water (95:5, volume ratio), flow rate 1.0 mL / min, detection wavelength 292 nm), the sample solution was injected into the liquid chromatograph for analysis, the concentration (C) was obtained from the standard curve according to the peak area, and the content was calculated using the formula tocopherol content (mg / kg) = (C×V×1000) / m (V is the volume of the sample solution, and m is the sample mass).

[0150] 6. Phytosterol Content

[0151] Principle: Gas chromatography-mass spectrometry (GC-MS) is used to separate phytosterols by gas chromatography column, and then qualitatively and quantitatively analyze them by mass spectrometer to accurately determine their content in peony seed oil.

[0152] Instruments and reagents: gas chromatography-mass spectrometry, HP-5MS capillary column (good for separation of phytosterols), n-hexane (chromatographic grade, used for extraction), phytosterol standards (such as β-sitosterol, stigmasterol, etc.).

[0153] step:

[0154] Sample preparation: Accurately weigh 0.2 g of peony seed oil sample, add potassium hydroxide-ethanol solution, and saponify in a water bath at 80°C for 1 h. After cooling, extract with n-hexane, dry the extract with anhydrous sodium sulfate, and concentrate to obtain a sample solution.

[0155] Standard curve drawing: prepare standard mixed solutions of plant sterols of different concentrations, analyze them by gas chromatography-mass spectrometry, and draw a standard curve with concentration as the horizontal axis and mass spectrum peak area as the vertical axis.

[0156] Sample determination: Under the set conditions (injection port 280°C, ion source 230°C, column temperature program), the sample solution was injected into the instrument for analysis, the concentration (C) was obtained from the standard curve according to the mass spectrum peak area, and the content was calculated by the formula: phytosterol content (mg / kg) = (C×V×1000) / m (V is the volume of the sample solution, and m is the sample mass).

[0157] 7. Squalene Content

[0158] Principle: High performance liquid chromatography (HPLC) is based on the separation of squalene on a reverse phase column based on the difference in the distribution coefficient of squalene. The quantitative analysis is performed by comparing the retention time and peak area with those of the standard to determine its content in peony seed oil.

[0159] Instruments and reagents: High performance liquid chromatograph equipped with UV detector, C18 reverse phase column (suitable for squalene separation), methanol (chromatographic grade, as mobile phase), squalene standard.

[0160] step:

[0161] Sample preparation: Accurately weigh 0.3 g of peony seed oil sample, place it in a 10 mL volumetric flask, dissolve it in methanol and make up to volume, filter the solution through a 0.45 μm filter membrane and inject it into the injection bottle.

[0162] Standard curve drawing: prepare squalene standard solutions of different concentrations, analyze them by high performance liquid chromatography, and draw a standard curve with concentration as the horizontal axis and peak area as the vertical axis.

[0163] Sample determination: Under the set conditions (mobile phase methanol-water (98:2, volume ratio), flow rate 1.2mL / min, detection wavelength 210nm), the sample solution was injected into the liquid chromatograph for analysis, the concentration (C) was obtained from the standard curve according to the peak area, and the content was calculated using the formula squalene content (mg / kg) = (C×V×1000) / m (V is the volume of the sample solution, and m is the sample mass).

[0164] According to the above method, the oil yield, α-linolenic acid extraction rate, acid value, peroxide value, tocopherol content, phytosterol content and squalene content of the peony seed oil obtained in Examples 1-5 and Comparative Examples 1-6 are shown in Table 1.

[0165] Table 1 Determination results of quality indexes of peony seed oil obtained by different preparation processes

[0166]

[0167]

[0168] As shown in Table 1, the oil yield, α-linolenic acid extraction rate, acid value, peroxide value, tocopherol content, phytosterol content and squalene content of the embodiment are substantially better than those of the comparative example, and the comprehensive performance is better, indicating that the preparation process of the present invention can prepare peony seed oil with high oil yield, high α-linolenic acid extraction rate, low acid value, high peroxide value and high active ingredient.

[0169] The specific analysis of the indicators in Table 1 is as follows:

[0170] 1. Oil yield

[0171] The oil yield of Example 1 reached 28.5%, and that of Example 3 was relatively high at 29.2%. The oil yields of Examples 2, 4, and 5 were 27.8%, 26.5%, and 27.2%, respectively. This shows that under different combinations of process parameters, there are certain differences in the oil yield, but the overall range is relatively stable and considerable. Among them, the process conditions of Example 3 may be more effective in promoting oil extraction, while the oil yield of Example 4 is relatively low, which may be due to the fact that the degree of destruction of the peony seed cell structure due to the setting of its microwave power and treatment time is not ideal, or some parameters in the extraction and molecular distillation process do not achieve the optimal oil extraction effect.

[0172] Since the comparative example 1 was not subjected to microwave treatment, the oil yield was only 23%, which was significantly lower than that of the embodiment. This fully demonstrates that microwave pretreatment plays an important role in improving the oil yield of peony seed oil. It can destroy the cell structure of peony seeds and promote the formation of oil channels, thereby increasing the extraction efficiency of oil. The different settings of extraction pressure and time in comparative examples 2 and 3 resulted in oil yields of 26% and 25.5%, respectively, which were also lower than those in embodiment 1, indicating that inappropriate extraction pressure and time will affect the extraction effect of oil.

[0173] 2. α-linolenic acid extraction rate

[0174] The extraction rate of α-linolenic acid showed some fluctuations in the examples. The extraction rate of Example 3 was the highest, which was 47.2%. Examples 1 and 2 were 46.5% and 45.8%, respectively. Examples 4 and 5 were relatively low, which were 44.5% and 45.2%. This shows that different process parameters have a significant effect on the extraction of α-linolenic acid. Higher microwave power and appropriate treatment time (such as Example 3) may help to better extract α-linolenic acid from peony seeds without destroying its structure. However, in Example 4, the extraction rate of α-linolenic acid may be reduced due to insufficient optimization of the parameters of microwave treatment or other steps.

[0175] Comparative Example 1 was not subjected to microwave treatment, and the α-linolenic acid extraction rate was only 42%, which once again proved the positive effect of microwave pretreatment on the extraction of α-linolenic acid. The changes in the extraction conditions of Comparative Examples 2 and 3 resulted in α-linolenic acid extraction rates of 43.5% and 43%, respectively, which were lower than those of Example 1, indicating that inappropriate extraction parameters would reduce the extraction effect of α-linolenic acid. The changes in the deacidification process of Comparative Examples 4 and 5 resulted in α-linolenic acid extraction rates of 41% and 40%, respectively, which were lower than those of the Example, indicating that inappropriate deacidification parameters would reduce the extraction effect of α-linolenic acid.

[0176] 3. Acid value

[0177] The acid value of Example 1 is 0.45 mg / g, the acid value of Example 3 is relatively low at 0.4 mg / g, and the acid values ​​of Examples 2, 4, and 5 are 0.5 mg / g, 0.6 mg / g, and 0.55 mg / g, respectively. This shows that different process combinations have a certain effect on the acid value of peony seed oil, and a lower acid value indicates that the quality of the oil is better. Among them, the process of Example 3 may be more effective in inhibiting oil rancidity, while the acid value of Example 4 is relatively high, which may be due to the increase in the degree of oil oxidation caused by certain parameters in the extraction or molecular distillation process, or the parameters during microwave treatment increase the free fatty acid content in the oil.

[0178] The acid value of Comparative Example 1 is 0.7 mg / g, which is significantly higher than that of Example 1, indicating that microwave pretreatment helps to reduce the acid value, probably because it can reduce the impurities and microbial content in the oil, thereby inhibiting the production of free fatty acids. The acid value of Comparative Example 2 is 0.8 mg / g. Higher extraction pressure and longer extraction time may lead to aggravated oxidation of the oil and increase the acid value. The acid value of Comparative Example 3 is 0.65 mg / g, which is also higher than that of Example 1, indicating that changes in the continuous extraction time will affect the acid value. The acid value of Comparative Example 4 is 1.2 mg / g, and the acid value of Comparative Example 5 is 0.85, indicating that only suitable deacidification parameters can effectively improve the deacidification efficiency, thereby reducing the acid value of the oil. The acid value of Comparative Example 6 is 0.52 mg / g, which is significantly higher than that of Example 1, indicating that scrapers of different materials will affect the deacidification efficiency, thereby increasing the acid value of the oil.

[0179] 4. Peroxide value

[0180] The peroxide value of Example 1 is 1.2 mmol / kg, the peroxide value of Example 3 is relatively low at 1.1 mmol / kg, and the peroxide values ​​of Examples 2, 4, and 5 are 1.3 mmol / kg, 1.4 mmol / kg, and 1.35 mmol / kg, respectively. The lower the peroxide value, the better the oxidative stability of the oil. The process of Example 3 may be more effective in reducing oil oxidation, while the peroxide value of Example 4 is relatively high, which may be due to the fact that its process parameters increase the chance of oil contacting oxygen during processing, or that certain parameters destroy the antioxidant components in the oil, thereby reducing the oxidative stability of the oil.

[0181] The peroxide value of comparative example 1 is 1.6mmol / kg, which is higher than that of example 1, indicating that microwave pretreatment helps to improve the oxidative stability of oils and fats. The peroxide value of comparative example 4 is as high as 2.2mmol / kg. This is because its feeding speed is too fast and the speed of the scraper is too high, which causes the oils and fats to be subjected to excessive shear force and heat during the molecular distillation process, accelerating the oxidation of the oils and fats, thereby increasing the peroxide value of the oils and fats. This shows that inappropriate feeding speed and speed of the scraper will increase the loss of oils and fats during deacidification. The peroxide value of comparative example 5 is 1.7mmol / kg. The lower feeding speed and speed of the scraper may affect the efficiency of molecular distillation, causing the oils and fats to stay in the equipment for too long, which will also lead to an increase in the peroxide value. The peroxide value of comparative example 6 is 1.4mmol / kg, which is lower than that of example 1, indicating that the scraper of inappropriate material may reduce the stability of the oils and fats due to uneven heat transfer.

[0182] 5. Tocopherol content

[0183] The tocopherol content of embodiment 1 is 820mg / kg, and the tocopherol content of embodiment 3 is relatively high 830mg / kg, and the tocopherol content of embodiment 2,4,5 is respectively 810mg / kg, 800mg / kg and 805mg / kg.Tocopherol is an important antioxidant, and the height of its content affects the quality and stability of peony seed oil.The process of embodiment 3 may be more effective in protecting tocopherol from being destroyed, and the tocopherol content of embodiment 4 is relatively lower than other embodiments, which may be due to its certain parameters in microwave treatment, extraction or molecular distillation process causing the loss of tocopherol to increase.

[0184] The tocopherol content of Comparative Example 1 is 780mg / kg, which is lower than Example 1, indicating that microwave pretreatment helps to retain tocopherol. The tocopherol contents of Comparative Examples 2, 3, 4, and 5 are 770mg / kg, 785mg / kg, 750mg / kg, and 760mg / kg, respectively, which are all lower than Example 1, indicating that tocopherol in grease can be more effectively retained only under a specific parameter range. In Comparative Example 6, due to the change in the scraper material, the tocopherol content is 790mg / kg, which is lower than Example 1, which may be because the polytetrafluoroethylene material, compared with the ceramic material, has a certain impact on the stability of tocopherol during molecular distillation.

[0185] 6. Phytosterol content

[0186] The phytosterol content of Example 1 is 2850 mg / kg, the phytosterol content of Example 3 is relatively high at 2880 mg / kg, and the phytosterol contents of Examples 2, 4, and 5 are 2820 mg / kg, 2790 mg / kg, and 2800 mg / kg, respectively. Phytosterols have a variety of physiological functions, and the level of their content is also one of the important indicators for measuring the quality of peony seed oil. The process of Example 3 may be more effective in extracting and retaining phytosterols, while the phytosterol content of Example 4 is relatively low, which may be due to the incomplete extraction of phytosterols caused by its process parameters or losses during processing.

[0187] The phytosterol content of Comparative Example 1 is 2700 mg / kg, which is lower than that of Example 1, indicating that microwave pretreatment has a positive effect on the extraction and retention of phytosterols. The phytosterol contents of Comparative Examples 2, 3, 4, and 5 are 2730 mg / kg, 2750 mg / kg, 2650 mg / kg, and 2680 mg / kg, respectively, indicating that only under a specific parameter range can the loss of phytosterols during extraction and deacidification be reduced. The phytosterol content of Comparative Example 6 is 2800 mg / kg, which is lower than that of Example 1. This may be because the scraper made of inappropriate material will reduce the deacidification efficiency, thereby increasing the loss of phytosterols.

[0188] 7. Squalene content

[0189] The squalene content of Example 1 is 26 mg / kg, the squalene content of Example 3 is relatively high at 27 mg / kg, and the squalene contents of Examples 2, 4, and 5 are 25 mg / kg, 24 mg / kg, and 24.5 mg / kg, respectively. Squalene is a component with health care functions, and the change in its content also reflects the effect of different processes on the components of peony seed oil. The process of Example 3 may be more effective in extracting squalene, while the squalene content of Example 4 is relatively low, which may be due to the fact that its process parameters are not conducive to the extraction and retention of squalene.

[0190] The squalene content of Comparative Example 1 is 22 mg / kg, which is lower than that of Example 1, indicating that microwave pretreatment helps to improve the extraction rate of squalene. The squalane contents of Comparative Examples 2, 3, 4, and 5 are 23 mg / kg, 23.5 mg / kg, 21 mg / kg, and 21.5 mg / kg, respectively, indicating that inappropriate extraction parameters and deacidification parameters will reduce the extraction effect of squalane. The squalane content of Comparative Example 6 is 25 mg / kg, which is lower than that of Example 1, indicating that the different materials of the scraper have a relatively low loss of squalane in oils and fats.

[0191] In summary, by analyzing the various index data of the embodiments and comparative examples, it can be seen that different process parameter combinations have a significant effect on the oil yield, α-linolenic acid extraction rate, acid value, peroxide value, tocopherol content, phytosterol content and squalene content of peony seed oil. In actual production, appropriate process parameters should be selected according to the specific requirements for product quality to obtain high-quality peony seed oil.

[0192] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A process for preparing peony seed oil, characterized in that: The following steps are involved: (1) heat-treating the peony seeds after impurity removal, drying, and crushing to obtain peony seed powder; (2) subjecting the peony seed powder obtained in step (1) to supercritical CO2 extraction to obtain crude peony seed oil; (3) deacidifying the crude peony seed oil obtained in step (2) to obtain deacidified peony seed oil; (4) filtering the deacidified peony seed oil obtained in step (3) to obtain peony seed oil.

2. The preparation process according to claim 1, characterized in that: In step (1), the heat treatment is to place the peony seeds after impurities removal on a conveyor belt of a microwave device and perform heat treatment using a microwave device.

3. The preparation process according to claim 2, characterized in that: In step (1), the heat treatment condition is to use a microwave device with a microwave power of 2-6 kW for 1-5 min.

4. The preparation process according to claim 1, characterized in that: In step (2), the supercritical CO2 extraction includes discontinuous cyclic high-pressure extraction and separation steps.

5. The preparation process according to claim 4, characterized in that: In step (2), the conditions of the discontinuous cycle high-pressure extraction in the supercritical CO2 extraction are 30-40°C and 20-30MPa. The extraction is stopped for 0.1h after each 0.3h of extraction, and then stopped for 0.1h after another 0.3h of extraction. The cycle is repeated until the total extraction time is 0.6-2.1h and the extraction is completed.

6. The preparation process according to claim 4, characterized in that: In step (2), the separation in the supercritical CO2 extraction includes primary separation and secondary separation, the conditions of the primary separation are 8-9MPa and 36-38°C, and the conditions of the secondary separation are 3-4MPa and 26-28°C.

7. The preparation process according to claim 1, characterized in that: In step (3), the feed rate of the peony seed oil obtained in step (2) during the deacidification treatment is 1-5 L / min.

8. The preparation process according to claim 1, characterized in that: In step (3), the scraping speed during the deacidification treatment is 5-15 r / min and the heating temperature is 150-200°C.

9. The preparation process according to claim 1, characterized in that: In step (3), the scraping film material in the deacidification treatment is a ceramic material.

10. The preparation process according to claim 1, characterized in that: In step (4), the filtration pressure is 0.2-0.4 MPa.

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