An ultrasonic weak alkali processing method to increase astragaloside A content

Abstract

This invention relates to the field of traditional Chinese medicine processing technology, and in particular to an ultrasonic weak alkali processing method for increasing the content of astragaloside A. This method solves the defects of existing astragaloside slicing processes, such as tool wear due to soil residue, microbial proliferation during the moistening stage, and the difficulty in dissolving astragaloside A due to its dense cell walls. Furthermore, the difficulty in achieving both acceptable slice size and content often results in substandard products and reduced astragaloside A content. This invention utilizes a composite aqueous solution of food-grade polysorbate 80 and food-grade glycerol to improve the retention rate of astragaloside A in astragaloside and reduce the loss of effective components during washing. The stabilization stage in gradient drying further stabilizes the retention of astragaloside A, inhibiting its oxidative decomposition. Combined with controlled moisture moistening to soften cell walls and facilitate astragaloside A dissolution, and anti-oxidation of the slices to ensure quality, this method increases the astragaloside A content in astragaloside slices.

Description

Technical Field

[0001] This invention relates to the field of traditional Chinese medicine processing technology, and in particular to an ultrasonic weak alkali processing method for increasing the content of astragaloside A. Background Technology

[0002] Astragaloside A is the core active ingredient in Astragalus membranaceus, which has the effects of enhancing immunity and protecting the cardiovascular system. Its ultrasonic weak alkaline processing method utilizes the cavitation effect of ultrasound to instantly destroy the plant cell wall, while the weak alkaline environment promotes the dissolution and release of astragaloside A.

[0003] Chinese Patent CN119792378A discloses a method for increasing the content of astragaloside A, which includes the following steps: (1) Harvesting: harvesting astragalus after the stems and leaves have withered and before the ground freezes, and shaking off the soil on the astragalus after harvesting; (2) Refrigeration: refrigerating the astragalus within 12 hours after harvesting; (3) Warming up: placing the astragalus after refrigeration in step (2) at 15-25°C for warming up; (4) Repeating steps (2) and (3) 0 times or more; (5) Storage: storing the astragalus after treatment in step (4) in an environment with suitable temperature and humidity for at least 0 days; (6) Drying: drying the astragalus after treatment in step (5). By treating harvested Astragalus membranaceus with physical methods such as refrigeration and rewarming, the synthesis of astragaloside A can be promoted, and the astragaloside A content can reach 0.114%, which can increase the astragaloside A content by more than 22%. This method is green and pollution-free, has no impact on the planting process of Astragalus membranaceus, and does not affect the yield of Astragalus membranaceus.

[0004] Regarding the above and existing related technologies, the inventors believe that the following defects often exist: Existing Astragalus processing technology adopts a process flow of shaking off the soil after harvesting, refrigeration and rewarming cycle treatment, storage at appropriate temperature and humidity, and drying. However, in production, this method does not perform ultrasonic and weak alkali combined cleaning treatment on the Astragalus raw materials, which cannot completely remove surface soil residues and easily causes wear on subsequent slicing tools. It does not adopt a humidity-controlled and sealed humidification process, which easily leads to microbial proliferation and contamination. It does not use weak acid rinsing and gradient drying to stabilize glycosides and break the dense cell wall lock and stabilize the astragaloside A component. Moreover, the slicing process lacks antioxidant protection measures, which leads to a reduction in the content of astragaloside A in the extracted Astragalus slices. Summary of the Invention

[0005] The technical problem to be solved by the present invention is that the existing technology has the following defects in the astragalus slicing process: due to soil residue leading to blade wear, microbial proliferation during the moistening stage, and astragaloside A being locked by dense cell walls and difficult to dissolve, and in addition, it is difficult to achieve both the slicing size and content, which easily leads to unqualified products, resulting in a decrease in the content of astragaloside A. To this end, we propose an ultrasonic weak alkali processing method to improve the content of astragaloside A.

[0006] To achieve the above objectives, this application adopts the following technical solution: an ultrasonic weak alkali processing method for increasing the content of astragaloside A, comprising the following steps: S1. Ultrasonic primary cleaning: 0.1%-0.3% food-grade polysorbate 80 and 0.05%-0.1% food-grade glycerol are mixed with water to obtain a composite aqueous solution. Then, the astragalus raw material and the composite aqueous solution are added together into the integrated tank-type ultrasonic cleaner to complete the static circulation cleaning operation. S2, Weak Alkali Deep Cleaning: A prepared sodium bicarbonate weak alkaline solution is used to continuously spray and rinse the surface of Astragalus membranaceus after S1 treatment using a spray-type circulating cleaning unit. S3, humidity control and humidification: Stack the Astragalus membranaceus treated by S2 to a thickness of ≤30cm, and place the whole thing in a constant temperature and humidity sealed humidification chamber, maintaining a constant relative humidity of 80% for 5 hours in a sealed humidification chamber. S4. Weak acid rinsing: Prepare a citric acid solution of a fixed concentration and use a full-area spray cleaning unit to spray and rinse the Astragalus membranaceus after S3 treatment. S5. Gradient drying: Astragalus membranaceus treated in S4 is transferred to a three-stage gradient hot air drying equipment and undergoes step drying in sequence through the dehydration stage, glycoside stabilization stage and tempering stage. During the glycoside stabilization stage, the micro-airflow disturbance module and the low-temperature plasma generation module are activated simultaneously for collaborative processing. S6. Astragalus Slices: The Astragalus, after being dried and shaped in S5, is transported to the CNC thickness slicing unit for precise thickness slicing. During the entire slicing process, the liquid spray pipeline is turned on simultaneously to spray ascorbic acid solution in real time.

[0007] Preferably, the operating frequency of the S1 integrated tank-type ultrasonic cleaner is set to 28kHz±2kHz, the power density of the whole machine is stably controlled at 0.25W / cm³, and the standard cleaning time for a single session is uniformly controlled within the range of 8min-10min.

[0008] Preferably, the sodium bicarbonate solution used in the S2 spray-type circulating cleaning unit has a mass concentration of 1.0%-1.1%, a pH of 8.0-8.2, a spray flow rate of 2m / s, a working pressure of 0.15MPa, and a standard circulating spray for a total of 3 times.

[0009] Preferably, in the S3 constant temperature and humidity sealed humidification silo operation, the entire process is sealed without opening or turning over the material, and the overall pH of the silo environment is maintained stably within the range of 7.8-8.0. The material can be left to stand until the specified time is up.

[0010] Preferably, in the S4 full-area spray cleaning unit, a multi-angle array of nozzles is used, and a 1% mass concentration of citric acid stock solution is supplied at a constant speed, so that only a single complete full-coverage spray process is required.

[0011] Preferably, in the dehydration stage of the S5 three-stage gradient hot air drying equipment, the directional direct hot air mode is used until the overall moisture content of Astragalus membranaceus drops to 45%, and the standard running time of this process is set to 1.5 hours.

[0012] Preferably, in the stabilization stage of the S5 three-stage gradient hot air drying equipment, the micro-airflow disturbance frequency is adjusted to be stable at 5Hz-8Hz, the output power of the low-temperature plasma generation module is 50W-80W, the processing is carried out until the moisture content is reduced to 30%, and the running time is set to 1h.

[0013] Preferably, in the tempering stage of the S5 three-stage gradient hot air drying equipment, an intermittent alternating air supply mode is adopted to continuously dry the Astragalus membranaceus until the final moisture content is stable at 25%±3%, and the total fixed processing time of the stage is 1 hour.

[0014] Preferably, when the S6 CNC thickness slicing unit cuts Astragalus membranaceus, the thickness is locked at 1.2mm ± 0.1mm, and an external spray pipe provides a constant supply of ascorbic acid solution with a mass concentration of 0.5%, which is then sprayed onto the surface of the cut Astragalus membranaceus.

[0015] Preferably, the feed speed of the entire S6 CNC fixed thickness slicer unit is uniformly set to 5mm / s, and the rated rotation speed of the matching carbide slicing blade is constantly controlled within the operating range of 300r / min.

[0016] The technical effects and advantages of this invention are as follows: In this invention, astragalus raw materials are first placed in an integrated tank-type ultrasonic cleaning machine along with a composite aqueous solution of polysorbate 80 and glycerol for initial cleaning. Then, a spray-type circulating cleaning unit is activated to continuously spray and rinse the surface of the raw materials three times with a weak alkaline sodium bicarbonate solution. Next, the treated astragalus is stacked and placed in a constant temperature and humidity sealed humidification chamber for sealed humidification. Afterward, the humidified astragalus is sprayed with a single, full-coverage citric acid solution using a multi-angle array nozzle of a full-area spray cleaning unit. The astragalus is then sent to a three-stage gradient hot air drying device for drying. Finally, it is dried using a CNC-controlled system. The cutting disc inside the thick slicing unit cuts Astragalus membranaceus into slices, and ascorbic acid solution is sprayed in real time through the pipeline during the entire slicing process to complete the processing. Through three-stage gradient hot air drying and the addition of polysorbate 80 and glycerol, Astragalus membranaceus can utilize the surface activity of polysorbate 80 and the moisturizing properties of glycerol during processing. Under the assistance of ultrasound, surface impurities are effectively removed and the medicinal tissue is softened. Combined with the directional conversion treatment of weak alkali humidification and weak acid neutralization, as well as the synergistic effect of micro-airflow and low-temperature plasma in the glycoside stabilization stage, the moisture gradient is precisely controlled while preventing the oxidation and loss of effective ingredients, thereby increasing the content of glycoside A in Astragalus membranaceus slices. Attached Figure Description

[0017] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts: Figure 1 This is a flowchart illustrating the overall steps of the present invention; Figure 2 This is a flowchart illustrating the overall process flow of the present invention. Figure 3 This is a detailed flowchart of the gradient drying steps of the present invention; Figure 4 This is a flowchart of the glycoside stabilization stage of the present invention; Figure 5 This is a chart comparing the astragaloside A content of the embodiments and comparative examples of the present invention; Figure 6 A chart showing the retention rate of astragaloside A at all stages of the process in this invention; Figure 7 This is a chart showing the trend of moisture content change of Astragalus membranaceus at each stage of the gradient drying process of this invention. Detailed Implementation

[0018] It is readily understood that, based on the technical solution of this invention, those skilled in the art can propose various interchangeable structural methods and implementations without altering the essential spirit of the invention. Therefore, the following detailed embodiments and accompanying drawings are merely illustrative examples of the technical solution of this invention and should not be considered as the entirety of the invention or as limitations or restrictions on the technical solution of this invention.

[0019] Comparative Example An ultrasonic weak alkali processing method for increasing astragaloside A content includes the following steps: S1. Ultrasonic primary cleaning: Add the Astragalus raw material into the integrated tank-type ultrasonic cleaner to complete the static circulation cleaning operation. S2, Weak Alkali Deep Cleaning: A prepared sodium bicarbonate weak alkaline solution is used to continuously spray and rinse the surface of Astragalus membranaceus after S1 treatment using a spray-type circulating cleaning unit. S3, humidity control and humidification: Stack the Astragalus membranaceus treated by S2 to a thickness of ≤30cm, and place the whole thing in a constant temperature and humidity sealed humidification chamber, maintaining a constant relative humidity of 80% for 5 hours in a sealed humidification chamber. S4. Weak acid rinsing: Prepare a citric acid solution of a fixed concentration and use a full-area spray cleaning unit to spray and rinse the Astragalus membranaceus after S3 treatment. S5. Gradient drying: The Astragalus membranaceus treated in S4 is transferred to the drying equipment and undergoes a step drying process, which is followed by a dehydration stage and a tempering stage. The astragaloside A content of the processed Astragalus membranaceus slices obtained in this comparative example was only 1.12%. For relevant content comparison results, please refer to [link to relevant data]. Figure 5 .

[0020] Example 1 Reference Figure 1 and Figure 2 An ultrasonic weak alkali processing method for increasing the content of astragaloside A includes the following steps: S1. Ultrasonic primary cleaning: Mix 0.1%-0.3% food-grade polysorbate 80 and 0.05%-0.1% food-grade glycerol with water to obtain a composite aqueous solution. Then, take fresh astragalus raw material, remove obvious impurities, and add it to the integrated tank-type ultrasonic cleaner. Set the cleaning machine operating frequency to 28kHz, control the overall power density to 0.25W / cm³, and the single cleaning time to 9min to complete the static circulation cleaning operation. S2, Weak Alkali Deep Cleaning: Prepare a sodium bicarbonate weak alkaline solution with a mass concentration of 1.05% and a pH of 8.1. Send the Astragalus membranaceus treated in S1 into a spray-type circulating cleaning unit. Set the spray flow rate to 2m / s and the working pressure to 0.15MPa. Spray and rinse the surface of Astragalus membranaceus continuously for a total of 3 times. S3. Humidity Control and Moistening: Stack the Astragalus membranaceus treated in S2 neatly, control the stacking thickness to 25cm, and place the whole thing in a constant temperature and humidity sealed moistening chamber. Maintain the relative humidity in the chamber at 80% and the pH at 7.9. Seal and moisten for 5 hours, and then let it stand until the specified time is up. S4. Weak acid rinsing: Prepare a 1% citric acid solution and send the Astragalus membranaceus treated in S3 into the full-area spray cleaning unit. The unit uses a multi-angle array of nozzles to supply citric acid solution at a uniform speed, and performs a single full-coverage spray rinsing treatment on the Astragalus membranaceus. S5, Gradient drying: such as Figure 3-4 As shown, the Astragalus membranaceus treated by S4 was transferred to a three-stage gradient hot air drying equipment and subjected to a step-by-step drying process consisting of a dehydration stage, a glycogen stabilization stage, and a tempering stage. In the dehydration stage, a directional direct-blowing hot air mode was used to dry the Astragalus membranaceus until the moisture content dropped to 45%, with a running time of 1.5 hours. In the glycogen stabilization stage, the micro-airflow disturbance module and the low-temperature plasma generation module were activated. The micro-airflow disturbance frequency was set to 6Hz, and the output power of the low-temperature plasma generation module was set to 65W. The process was carried out until the moisture content of the Astragalus membranaceus dropped to 30%, with a running time of 1 hour. In the tempering stage, an intermittent alternating air supply mode was used to continuously dry the Astragalus membranaceus until the final moisture content stabilized at 25%, with a running time of 1 hour. S6. Slicing: The Astragalus membranaceus dried and shaped in S5 is fed into the CNC thickness slicing unit. The feed speed of the unit is set to 5 mm / s, and the rotation speed of the matching carbide slicing disc is 300 r / min. The Astragalus membranaceus is precisely sliced ​​to a thickness of 1.2 mm. The liquid spray pipeline is turned on simultaneously throughout the slicing process to provide a constant supply of 0.5% mass concentration ascorbic acid solution for real-time spraying. The astragaloside A content of the processed Astragalus membranaceus slices obtained in this embodiment reached 1.82%. The relevant content detection results can be found in [reference needed]. Figure 5 .

[0021] Example 2 Reference Figure 1 and Figure 2 An ultrasonic weak alkali processing method for increasing the content of astragaloside A includes the following steps: S1. Ultrasonic primary cleaning: Mix 0.1%-0.3% food-grade polysorbate 80 and 0.05%-0.1% food-grade glycerol with water to obtain a composite aqueous solution. Then, take fresh astragalus raw material, remove obvious impurities, and add it to the integrated tank-type ultrasonic cleaning machine. Set the cleaning machine operating frequency to 26kHz, control the overall power density to 0.25W / cm³, and the single cleaning time to 8min. Complete the static circulation cleaning operation. S2, Weak Alkali Deep Cleaning: Prepare a sodium bicarbonate weak alkaline solution with a mass concentration of 1% and a pH of 8.0. Send the Astragalus membranaceus treated in S1 into a spray-type circulating cleaning unit. Set the spray flow rate to 2m / s and the working pressure to 0.15MPa. Spray and rinse the surface of Astragalus membranaceus continuously for a total of 3 times. S3. Humidity Control and Humidification: Stack the Astragalus membranaceus treated in S2 neatly, control the stacking thickness to 30cm, and place the whole thing in a constant temperature and humidity sealed humidification chamber. Maintain the relative humidity in the chamber at 80% and the pH at 7.8. Humidify for 5 hours and then let it stand until the specified time is up. S4. Weak acid rinsing: Prepare a 1% citric acid solution and send the Astragalus membranaceus treated in S3 into the full-area spray cleaning unit. The unit uses a multi-angle array of nozzles to supply citric acid solution at a uniform speed, and performs a single full-coverage spray rinsing treatment on the Astragalus membranaceus. S5, Gradient drying: such as Figure 3-4As shown, the Astragalus membranaceus treated by S4 was transferred to a three-stage gradient hot air drying equipment and subjected to a step-by-step drying process consisting of a dehydration stage, a glycogen stabilization stage, and a tempering stage. In the dehydration stage, a directional direct-blowing hot air mode was used to dry the Astragalus membranaceus until the moisture content dropped to 45%, with a running time of 1.5 hours. In the glycogen stabilization stage, the micro-airflow disturbance module and the low-temperature plasma generation module were activated. The micro-airflow disturbance frequency was set to 5Hz, and the output power of the low-temperature plasma generation module was set to 50W. The process was carried out until the moisture content of the Astragalus membranaceus dropped to 30%, with a running time of 1 hour. In the tempering stage, an intermittent alternating air supply mode was used to continuously dry the Astragalus membranaceus until the final moisture content stabilized at 23%, with a running time of 1 hour. S6. Slicing: The Astragalus membranaceus dried and shaped in S5 is fed into the CNC thickness slicing unit. The feed speed of the unit is set to 5 mm / s, and the rotation speed of the matching carbide slicing disc is 280 r / min. The Astragalus membranaceus is precisely sliced ​​to a thickness of 1.1 mm. The liquid spray pipeline is turned on simultaneously throughout the slicing process to provide a constant supply of 0.5% mass concentration ascorbic acid solution for real-time spraying. The astragaloside A content of the processed Astragalus membranaceus slices obtained in this embodiment reached 1.82%. The relevant content detection results can be found in [reference needed]. Figure 5 .

[0022] Example 3 Reference Figure 1 and Figure 2 An ultrasonic weak alkali processing method for increasing the content of astragaloside A includes the following steps: S1. Ultrasonic primary cleaning: Mix 0.1%-0.3% food-grade polysorbate 80 and 0.05%-0.1% food-grade glycerol with water to obtain a composite aqueous solution. Then, take fresh astragalus raw material, remove obvious impurities, and add it to the integrated tank-type ultrasonic cleaner. Set the operating frequency of the cleaner to 30kHz, control the power density of the whole machine to 0.25W / cm³, and the cleaning time of a single cleaning session to 10min. Complete the static circulation cleaning operation. S2, Weak Alkali Deep Cleaning: Prepare a sodium bicarbonate weak alkaline solution with a mass concentration of 1.1% and a pH of 8.2. Send the Astragalus membranaceus treated in S1 into a spray-type circulating cleaning unit. Set the spray flow rate to 2m / s and the working pressure to 0.15MPa. Spray and rinse the surface of Astragalus membranaceus continuously for a total of 3 times. S3. Humidity Control and Humidification: Stack the Astragalus membranaceus treated in S2 neatly, control the stacking thickness to 20cm, and place the whole thing in a constant temperature and humidity sealed humidification chamber. Maintain the relative humidity in the chamber at 80% and the pH at 8.0, seal and humidify for 5 hours, and then let it stand until the specified time is up. S4. Weak acid rinsing: Prepare a 1% citric acid solution and send the Astragalus membranaceus treated in S3 into the full-area spray cleaning unit. The unit uses a multi-angle array of nozzles to supply citric acid solution at a uniform speed, and performs a single full-coverage spray rinsing treatment on the Astragalus membranaceus. S5, Gradient drying: such as Figure 3-4 As shown, the Astragalus membranaceus treated by S4 was transferred to a three-stage gradient hot air drying equipment and subjected to a step-by-step drying process consisting of a dehydration stage, a glycogen stabilization stage, and a tempering stage. In the dehydration stage, a directional direct-blowing hot air mode was used to dry the Astragalus membranaceus until the moisture content dropped to 45%, with a running time of 1.5 hours. In the glycogen stabilization stage, the micro-airflow disturbance module and the low-temperature plasma generation module were activated. The micro-airflow disturbance frequency was set to 8Hz, and the output power of the low-temperature plasma generation module was set to 80W. The process was carried out until the moisture content of the Astragalus membranaceus dropped to 30%, with a running time of 1 hour. In the tempering stage, an intermittent alternating air supply mode was used to continuously dry the Astragalus membranaceus until the final moisture content stabilized at 27%, with a running time of 1 hour. S6. Slicing: The Astragalus membranaceus after drying and shaping in S5 is fed into the CNC thickness slicing unit. The feed speed of the unit is set to 5 mm / s, and the rotation speed of the matching carbide slicing disc is 300 r / min. The Astragalus membranaceus is precisely sliced ​​to a thickness of 1.3 mm. The liquid spray pipeline is turned on simultaneously throughout the slicing process to provide a constant supply of 0.5% mass concentration ascorbic acid solution for real-time spraying. The astragaloside A content of the processed Astragalus membranaceus slices obtained in this embodiment reached 1.82%. The relevant content detection results can be found in [reference needed]. Figure 5 .

[0023] Comparison Table of Core Process Parameters in Examples

[0024] Working Principle: After removing obvious impurities from fresh astragalus root raw materials, they are immersed in a composite aqueous solution containing 0.2% food-grade polysorbate 80 and 0.08% food-grade glycerol. Through the synergistic effect of the two, a protective film can be formed on the surface of the astragalus root, reducing the dissolution and loss of astragaloside A. At the same time, polysorbate 80 can reduce the surface tension of the cleaning solution and enhance the cleaning effect, while glycerol helps to improve the stability of the protective film. Neither of them damages the effective components inside the astragalus root. Then, the raw materials are cleaned for 9 minutes using an integrated tank-type ultrasonic cleaner with a vibration frequency of 28kHz and a power density of 0.25W / cm³. This not only quickly removes surface impurities but also... A protective film is formed by the synergistic effect of polysorbate 80 and glycerol, reducing the dissolution and loss of astragaloside A without damaging the internal structure of the effective components. Subsequently, a deep cleaning is performed by circulating and spraying three times with a 1.05% (w / w) sodium bicarbonate weak alkaline solution (pH 8.1) at a flow rate of 2 m / s and a working pressure of 0.15 MPa. This neutralizes surface acidic impurities while preventing the strong alkali from damaging astragaloside A, achieving thorough impurity removal. Afterward, the astragalus is stacked in 25cm thickness and placed in a constant temperature and humidity sealed chamber (80% relative humidity, pH 7.9) for 5 hours to ensure uniform internal moisture distribution, laying the foundation for subsequent processes and reducing... To minimize the loss of astragaloside A during the drying process, a 1% citric acid solution is used for full-coverage spraying to neutralize residual weak alkali and adjust the surface pH to neutral, further reducing impurities and ensuring the stability of astragaloside A. Following this, a three-stage gradient hot air drying process is initiated. First, directional direct-blowing hot air is used for 1.5 hours to dehydrate to a moisture content of 45%, rapidly removing surface free moisture and reducing astragaloside A dissolution. Then, micro-airflow disturbance and low-temperature plasma are used in synergistic treatment for 1 hour to reduce the moisture content to 30%. Micro-airflow disturbance ensures uniform heating of the astragaloside, preventing localized overheating that could lead to astragaloside A decomposition, while low-temperature plasma effectively inhibits the oxidation of astragaloside A. The synergistic effect of these two methods achieves stable retention of astragaloside A. Finally, the astragalus is dried for 1 hour in an intermittent air-blowing mode until the moisture content reaches 25%, avoiding loss of astragaloside A due to tissue damage. The dried and shaped astragalus is then sliced ​​into 1.2mm thick slices at a feed speed of 5mm / s and a blade rotation speed of 300r / min. Simultaneously, a 0.5% concentration of ascorbic acid solution is sprayed to prevent oxidation of astragaloside A, ensuring slice uniformity and processing quality. Through the synergistic effect of the entire process—compound aqueous solution for glycoside protection, weak base-weak acid directional treatment, gradient drying for glycoside stabilization, and slice oxidation prevention—efficient retention and increased content of astragaloside A are achieved. Quantitative analysis of the astragaloside A content in the finished product is shown in [link to product details]. Figure 5 The changes in methyl glycoside retention rate throughout the entire process are shown in the figure. Figure 6 For precise control parameters of moisture content at each stage of gradient drying, see [link to relevant documentation]. Figure 7 .

[0025] The technical scope of this invention is not limited to the content described above. Those skilled in the art can make various modifications and variations to the above embodiments without departing from the technical concept of this invention, and all such modifications and variations should fall within the protection scope of this invention.

Claims

1. A method for ultrasonic weak alkali processing to increase the content of astragaloside A, characterized in that, Includes the following steps: S1. Ultrasonic primary cleaning: 0.1%-0.3% food-grade polysorbate 80 and 0.05%-0.1% food-grade glycerol are mixed with water to obtain a composite aqueous solution. Then, the astragalus raw material and the composite aqueous solution are added together into the integrated tank-type ultrasonic cleaner to complete the static circulation cleaning operation. S2, Weak Alkali Deep Cleaning: A prepared sodium bicarbonate weak alkaline solution is used to continuously spray and rinse the surface of Astragalus membranaceus after S1 treatment using a spray-type circulating cleaning unit. S3, humidity control and humidification: Stack the Astragalus membranaceus treated in S2 to a thickness of ≤30cm, and place the whole thing in a constant temperature and humidity sealed humidification chamber, maintaining a constant relative humidity of 80% for 5 hours in a sealed humidification chamber. S4. Weak acid rinsing: Prepare a citric acid solution of a fixed concentration and use a full-area spray cleaning unit to spray and rinse the Astragalus membranaceus after S3 treatment. S5. Gradient drying: Astragalus membranaceus treated in S4 is transferred to a three-stage gradient hot air drying equipment and undergoes step drying in sequence through the dehydration stage, glycoside stabilization stage and tempering stage. During the glycoside stabilization stage, the micro-airflow disturbance module and the low-temperature plasma generation module are activated simultaneously for collaborative processing. S6. Astragalus Slices: The Astragalus, after being dried and shaped in S5, is transported to the CNC thickness slicing unit for precise thickness slicing. During the entire slicing process, the liquid spray pipeline is turned on simultaneously to spray ascorbic acid solution in real time.

2. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: The operating frequency of the S1 integrated tank-type ultrasonic cleaner is set to 28kHz±2kHz, the power density of the whole machine is stably controlled at 0.25W / cm³, and the standard cleaning time for a single session is uniformly controlled within the range of 8min-10min.

3. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: The sodium bicarbonate solution used in the S2 spray-type circulating cleaning unit has a mass concentration of 1.0%-1.1%, a pH of 8.0-8.2, a spray flow rate of 2m / s, a working pressure of 0.15MPa, and a standard circulating spray for a total of 3 times.

4. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: During the operation in the S3 constant temperature and humidity sealed humidification chamber, the entire process is sealed without opening or turning over the material. The overall pH of the chamber environment is maintained stably within the range of 7.8-8.

0. The material is left to stand until the specified time is up.

5. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: The S4 full-area spray cleaning unit adopts a multi-angle array of nozzles and is supplied with a 1% mass concentration of citric acid stock solution at a constant speed, so that only a single complete full-coverage spray process is required.

6. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: In the dehydration stage of the S5 three-stage gradient hot air drying equipment, the directional direct hot air blowing mode is used until the overall moisture content of Astragalus membranaceus drops to 45%. The standard running time for this process is set to 1.5 hours.

7. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: In the stabilization stage of the S5 three-stage gradient hot air drying equipment, the micro-airflow disturbance frequency is adjusted to be stable at 5Hz-8Hz, the output power of the low-temperature plasma generation module is 50W-80W, and the processing is carried out until the moisture content is reduced to 30%, with the running time set to 1h.

8. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: In the tempering stage of the S5 three-stage gradient hot air drying equipment, the intermittent alternating air supply mode is adopted to continuously dry the Astragalus membranaceus until the final moisture content is stable at 25%±3%, and the total fixed processing time of the stage is 1 hour.

9. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: When Astragalus membranaceus is cut using the S6 CNC thickness slicing unit, the thickness is locked at 1.2mm ± 0.1mm. An external spray pipe provides a constant supply of ascorbic acid solution with a mass concentration of 0.5%, which is then sprayed onto the surface of the cut Astragalus membranaceus.

10. The ultrasonic weak alkali processing method for increasing astragaloside A content as described in claim 1, characterized in that: The feed speed of the S6 CNC fixed thickness slicing unit is uniformly set to 5mm / s, and the rated rotation speed of the matching carbide slicing blade is constantly controlled within the operating range of 300r / min.

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