Pulse high pressure-based pretreatment and drying method for guishiwai traditional Chinese medicine decoction pieces

Abstract

The present application relates to the technical field of traditional Chinese medicine processing, and particularly relates to a Guishiyi traditional Chinese medicine decoction piece pretreatment drying method based on pulse high pressure, which solves the problem that high temperature leads to loss of aroma, a substantial decrease in volatile oil content, and direct weakening of drug efficacy in the prior art; and for high-sugar medicinal materials such as longan arillus, high temperature easily causes surface crust or internal charring, affecting appearance and taste. The Guishiyi traditional Chinese medicine decoction piece pretreatment drying method based on pulse high pressure comprises raw material cleaning and grading pretreatment, and the collected Guishiyi traditional Chinese medicine is removed from impurities and non-medicinal parts, and the surface of the medicinal material is quickly cleaned of mud and dust using flowing pure water. The overall drying cycle of the present application is compressed from 18-24 hours of the conventional method to 6-12 hours, and energy consumption is reduced by about 30%; finally, the decoction piece is subjected to microbial limit examination, the total number of aerobic bacteria is less than 10³ CFU / g, and the number of molds and yeasts is less than 10² CFU / g.

Description

Technical Field

[0001] The present invention relates to the technical field of traditional Chinese medicinal material processing, in particular to a pretreatment and drying method for Guishiwei traditional Chinese medicinal decoction pieces based on pulse high voltage. Background Art

[0002] As an outstanding representative of authentic medicinal materials in Guangxi, Guishiwei includes ten kinds of Chinese medicinal materials with strong regional characteristics and clinical values, namely Cinnamomi Cortex (including Cinnamomi Ramulus), Siraetiae Fructus, Illicii Veri Fructus, Guangxi Curcumae Rhizoma (including Curcumae Kwangsienis Radix), Longan Arillus (dried longan), Sophorae Tonkinensis Radix et Rhizoma, Spatholobi Caulis, Abri Herba, Zanthoxyli Nitidi Radix and Pheretima Guanchongensis. Relying on the unique geographical climate and biodiversity of Guangxi, these medicinal materials have formed the authentic characteristics of stable quality and remarkable curative effect. For example, Cinnamomi Cortex is famous for its high volatile oil content and strong aroma, and is a good medicine for warming and unblocking meridians; Siraetiae Fructus takes mogroside as its core component and has the effect of clearing heat and moistening lung. However, as a natural plant or animal-derived product, Guishiwei usually contains high moisture after harvesting. If scientific pretreatment and drying are not carried out in time, it is very prone to mildew, moth infestation or degradation of active ingredients. Therefore, drying is a key link to guarantee its medicinal quality and storage safety.

[0003] In the prior art, the pretreatment and drying of Guishiwei traditional Chinese medicinal decoction pieces mainly relies on traditional natural sun-drying, hot air drying or simple vacuum drying technology. Although these methods are widely used, they have exposed obvious drawbacks in actual production. First, traditional hot air drying often has high temperature and long drying cycle. For medicinal materials rich in volatile oil such as Cinnamomi Cortex and Illicii Veri Fructus, high temperature will lead to loss of aroma and a significant decrease in volatile oil content, which directly weakens the efficacy; for medicinal materials with high sugar content such as Longan Arillus, high temperature easily causes surface crusting or internal coking, which affects the appearance and taste. Secondly, the mass transfer efficiency of conventional drying methods is low, and moisture usually gradually migrates from the surface to the interior of the medicinal material, which easily leads to the phenomenon of "dry outside but wet inside", resulting in the risk of moisture regain and mildew of the medicinal material during storage. In addition, existing drying methods can hardly meet the special requirements of different texture medicinal materials in Guishiwei. For rhizome medicinal materials with hard texture and fruit medicinal materials with soft texture, there is a lack of an efficient pretreatment technology that can break the cell wall resistance, accelerate the escape of internal moisture and retain heat-sensitive active ingredients to the greatest extent. Therefore, there is an urgent need for a pretreatment and drying method for Guishiwei traditional Chinese medicinal decoction pieces based on pulse high voltage to solve the above problems. Summary of the Invention

[0004] The purpose of the present invention is to provide a pretreatment and drying method for Guishiwei traditional Chinese medicinal decoction pieces based on pulse high voltage, which solves the problems existing in the prior art that high temperature will lead to loss of aroma, a significant decrease in volatile oil content and directly weaken the efficacy; and for medicinal materials with high sugar content such as Longan Arillus, high temperature easily causes surface crusting or internal coking, which affects the appearance and taste.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for pre-treatment and drying of Gui Shiwei traditional Chinese medicine slices based on pulsed high voltage includes the following steps: Step 1: Raw material cleaning and grading pretreatment. Remove impurities and non-medicinal parts from the harvested Gui Shi Wei Chinese medicinal materials. Use running pure water to quickly wash the mud and dust off the surface of the medicinal materials. Grade the medicinal materials according to their texture and shape. Step 2: Pulsed high-voltage electric field treatment. The pre-treated medicinal materials are spread flat on an insulating porous tray and placed in the pulsed high-voltage treatment chamber. Step 3: Vacuum pulsed permeation, transferring the medicinal materials after pulsed high-pressure treatment to the material tray inside the vacuum drying oven; Step 4: Variable temperature combined drying, using a segmented variable temperature drying process to dehydrate and dry the medicinal materials; Step 5: Softening and Moistening. After drying, remove the medicinal materials and place them in a sealed container. Let them stand at room temperature for 24-48 hours. Step Six: Sterilization and Packaging. The softened medicinal slices are then subjected to ultraviolet sterilization or low-temperature ozone sterilization again, followed by vacuum packaging or nitrogen-filled packaging according to pharmacopoeia standards to obtain the finished product.

[0006] Preferably, the harvested Gui Shi Wei Chinese medicinal herbs, including cinnamon, monk fruit, star anise, Guangxi turmeric, longan pulp, sophora root, chicken blood vine, chicken bone grass, thorny thorn, and earthworm, are placed on a clean workbench. They are manually selected to remove mud, stones, insect-damaged parts, moldy parts, and other non-medicinal parts. The herbs are then transferred to a washing tank and rinsed with room-temperature purified water at a flow rate of 0.5–1.0 m / s for 2–5 minutes to wash away dust, impurities, and some microorganisms adhering to the surface. After washing, the herbs are classified according to their botanical parts and physical characteristics: root and rhizome herbs such as sophora root, thorny thorn, chicken blood vine, and Guangxi turmeric, and whole herb herbs such as chicken bone grass, are processed using stainless steel... The slicer cuts the herbs into oblique slices 2–5 mm thick or segments 1–3 cm long. For fruit-based herbs, monk fruit can be kept whole or split open along the equator to remove the seeds. Longan pulp needs to have its outer shell removed and the pit removed. Star anise is kept intact or broken into single petals according to subsequent processing requirements. For bark-based herbs such as cinnamon and cassia branches, the rough outer bark is first scraped off with a bamboo knife, then rolled into a tube or cut into small square pieces of 2–4 cm. For animal-based herbs such as earthworm, the herbs are longitudinally split along the midline of the abdomen, and the internal organs are removed with a soft brush and rinsed repeatedly with clean water until the body cavity is clean. All processed herbs are laid flat on a food-grade plastic screen and allowed to air dry naturally in a ventilated room for 10–30 minutes to allow surface moisture to drip off, forming the material to be processed.

[0007] Preferably, the drained medicinal materials are evenly spread on an insulating porous tray made of polytetrafluoroethylene or ceramic, with a single layer thickness controlled at 1–3 cm to avoid stacking and heavy pressure; the tray is pushed into the pulse high-voltage processing chamber, the chamber door is closed and sealed; the parallel plate electrode system is adjusted so that the distance between the upper and lower electrodes is 5–15 cm to ensure that the medicinal materials are in a region with a uniform electric field intensity distribution; the high-voltage pulse power supply is started, and the output parameters are set as follows: electric field intensity 20–40 kV / cm, pulse frequency 50–200 Hz, pulse width 2–5 μs, and pulse wave... The wave shape is a square wave or an exponentially decaying wave. Under the conditions of an ambient temperature of 20–25℃ and a relative humidity of 40%–60%, a high-voltage pulse is continuously applied to the medicinal material for 10–20 minutes. During this process, the electric field acts on the inside of the medicinal material tissue, causing a transmembrane potential difference across the cell membrane. When the critical threshold is exceeded, irreversible electroporation is triggered, forming nanoscale microporous channels on the cell membrane and cell wall. After the treatment is completed, the high-voltage power supply is turned off, the treatment chamber door is opened, the tray is taken out, and there are no obvious traces of charring or carbonization on the surface of the medicinal material, maintaining its original color and shape.

[0008] Preferably, the medicinal materials treated with pulsed high pressure are transferred to stainless steel material trays, arranged in a single layer, and placed into a vacuum drying oven with a programmable control system. The oven door is closed and the vacuum system is activated. A rotary vane vacuum pump gradually reduces the pressure inside the oven from atmospheric pressure to -0.08 MPa to -0.095 MPa, maintaining this negative pressure for 10–15 minutes. This allows the air in the interstitial spaces of the medicinal materials to expand due to the pressure reduction and escape from the micropores. Subsequently, the vacuum pump is turned off, and the inlet valve is slowly opened to introduce air into the oven through a 0.22 μm filter. Dry compressed air or high-purity nitrogen filtered through a membrane is used to restore the pressure inside the chamber to atmospheric pressure. This process is completed within 2–5 minutes. After the pressure is balanced, the vacuum pump is restarted for a second vacuuming operation. The above "vacuuming-gas return" cycle is repeated a total of 3–5 times. During each cycle, the entry and exit of gas creates a dynamic pressure difference inside the medicinal material, which promotes further expansion of the intercellular spaces and displaces residual gas, creating a low-resistance path for subsequent moisture migration. After the last gas return is completed, the chamber is kept at atmospheric pressure to prepare for the next drying stage.

[0009] Preferably, after drying, the heating and fan systems are turned off. After the temperature inside the chamber naturally drops to room temperature, the medicinal materials are removed from the material tray and placed into a sealed food-grade polyethylene or stainless steel container with a lid. No desiccant or filler is added to the container. The stacking height of the medicinal materials should not exceed 30cm. The container is placed in a constant temperature and humidity room with a temperature of 20–25℃ and a relative humidity of 50%–60% and left to stand for 24–48 hours. During this period, spontaneous diffusion occurs inside the medicinal materials due to the existence of a moisture gradient. Moisture in high moisture content areas migrates to low moisture content areas, eventually achieving a uniform overall moisture distribution. After softening, the medicinal materials feel soft and pliable, without obvious brittleness or localized dampness.

[0010] Preferably, the softened medicinal slices are laid flat on a conveyor belt and sent into an ultraviolet sterilization chamber, where they are irradiated with a low-pressure mercury lamp array with a wavelength of 254nm, an irradiation intensity of 50–100μW / cm², and a treatment time of 5–10 minutes; or a low-temperature ozone generator is used, and ozone gas with a concentration of 5–10mg / L is introduced to fumigate in a sealed chamber for 15–20 minutes; after sterilization, the medicinal slices are weighed according to specifications, packed into aluminum foil composite bags or aluminized film bags, vacuum-packed to a residual pressure ≤-0.09MPa using a vacuum packaging machine, and then heat-sealed; or nitrogen-filled packaging machine is used to inject nitrogen gas with a purity ≥99.9% to a positive pressure of 0.02–0.05MPa inside the bag and then seal it; the packaged finished products are labeled and stored in a cool, dry place.

[0011] This invention has at least the following beneficial effects: This invention improves the retention rate of volatile oil-rich medicinal materials such as cinnamon and star anise by more than 25% compared to traditional hot air drying after the entire process, as determined by gas chromatography-mass spectrometry. The saponins in monk fruit are effectively protected during the low-temperature and low-humidity stage, with content fluctuations controlled within ±3%. Rhizome and root medicinal materials such as Curcuma zedoaria and Sophora tonkinensis slices show no obvious shrinkage or cracking after drying, have uniform cross-sections, and a moisture content distribution standard deviation of less than 1.2%. The percentage indicates that the phenomenon of "dry outside and moist inside" has been basically eliminated; under the synergistic effect of pulsed electric field and vacuum pulse, the tissue looseness of animal-derived medicinal materials such as earthworm increases, the drying time is shortened by about 40%, and no off-odor or protein denaturation and aggregation occurs; the overall drying cycle is reduced from 18-24 hours in conventional methods to 6-12 hours, and energy consumption is reduced by about 30%; the final medicinal slices are tested for microbial limits, and the total number of aerobic bacteria is less than 10³ CFU / g, and the number of molds and yeasts is less than 10² CFU / g. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0013] Example 1 It includes the following steps: Step 1: Raw material cleaning and grading pretreatment. Remove impurities and non-medicinal parts from the harvested Gui Shi Wei Chinese medicinal materials. Use running pure water to quickly wash the mud and dust off the surface of the medicinal materials. Grade the medicinal materials according to their texture and shape. Step 2: Pulsed high-voltage electric field treatment. The pre-treated medicinal materials are spread flat on an insulating porous tray and placed in the pulsed high-voltage treatment chamber. Step 3: Vacuum pulsation permeation: transfer the medicinal materials treated by pulsed high pressure to the material tray in a vacuum drying oven; Step 4: Variable-temperature combined drying: dehydrate and dry the medicinal materials by adopting a segmented variable-temperature drying process; Step 5: Softening back and moisture equalization: after drying is completed, take out the medicinal materials, place them in a closed container, and let them stand at room temperature for 24-48 hours; Step 6: Sterilization and packaging: subject the re-softened decoction pieces to ultraviolet sterilization or low-temperature ozone sterilization again, then carry out vacuum packaging or nitrogen-filled packaging according to pharmacopoeia standards, and the finished product is obtained.

[0014] Through the systematic series arrangement of manual sorting operation table, spray cleaning tank, stainless steel slicer, pulsed high pressure treatment chamber (with parallel plate electrode and high voltage pulse power supply), program-controlled vacuum drying oven, constant temperature and humidity conditioning chamber, and integrated ultraviolet / ozone sterilization-packaging equipment, the six working procedures of cleaning and grading, electric field perforation, vacuum pulsation, variable temperature drying, moisture equalization and re-softening, and aseptic packaging are completed successively in the working flow. This achieves the comprehensive effects of efficient dehydration, high retention of heat-sensitive components, complete tissue structure, controllable microorganisms and consistent batch quality for Guishiwei decoction pieces without relying on chemical additives or high-temperature long-time heat treatment.

[0015] Example 2 The harvested Guishiwei Chinese medicinal materials, including Cinnamomi Cortex, Siraetiae Fructus, Illicii Veri Fructus, Curcumae Guangxiensis Rhizoma, Longan Arillus, Sophorae Tonkinensis Radix et Rhizoma, Spatholobi Caulis, Abri Herba, Zanthoxyli Nitidi Radix and Pheretima Guangxiensis, are placed on a clean operation table, and manually sorted to remove silt, stones, worm-eaten products, moldy products and other non-medicinal parts; then the medicinal materials are transferred to a cleaning tank, sprayed and washed with normal temperature pure water at a flow rate of 0.5–1.0m / s for a duration of 2–5 minutes, so that the dust, impurities and part of microorganisms attached to the surface of the medicinal materials are washed off; after cleaning, classified treatment is carried out according to the botanical parts and physical properties of the medicinal materials: for rhizome medicinal materials such as Sophorae Tonkinensis Radix et Rhizoma, Zanthoxyli Nitidi Radix, Spatholobi Caulis, Curcumae Guangxiensis Rhizoma, and whole herb medicinal materials such as Abri Herba, a stainless steel slicer is used to cut them into oblique pieces with a thickness of 2–5mm or segments with a length of 1–3cm; among fruit medicinal materials, Siraetiae Fructus can be kept as a whole fruit or cut open along the equatorial direction to remove seeds, Longan Arillus needs to be peeled and cored, while Illicii Veri Fructus remains in complete star shape or broken into single petals according to subsequent processing requirements; for bark medicinal materials such as Cinnamomi Cortex and Cinnamomi Ramulus, first scrape off the rough old bark on the surface with a bamboo knife, then roll it into a cylinder or cut into small square pieces of 2–4cm; for animal medicinal material Pheretima Guangxiensis, cut it open longitudinally along the ventral midline, remove visceral residues with a soft brush, and repeatedly rinse with clean water until the body cavity is clean; all treated medicinal materials are laid flat on food-grade plastic screens, and naturally drained in a ventilated room for 10–30 minutes, so that free water on the surface drips off to form materials to be treated.

[0016] By using a clean operating table, a room temperature pure water spray system with a flow rate of 0.5–1.0 m / s, a food-grade stainless steel slicer (adjustable thickness 2–5 mm), a bamboo peeler, a soft brush, and a perforated plastic screen, the workflow performs differentiated pretreatments such as cutting, pitting, peeling, and washing on root and rhizome herbs (such as Sophora tonkinensis and Curcuma zedoaria), whole herb herbs (such as Abrus precatorius), fruit herbs (such as Siraitia grosvenorii, Longan pulp, and star anise), bark herbs (such as Cinnamomum cassia and Cinnamomum cassia twig), and animal herbs (such as Pheretima aspergillum). After draining for 10–30 minutes in a ventilated environment, the workflow achieves the effects of improved surface cleanliness of medicinal materials, thorough removal of non-medicinal parts, standardization of morphology and specifications, and uniform stress distribution in subsequent processing.

[0017] Example 3 Spread the drained medicinal materials evenly on an insulating porous tray made of polytetrafluoroethylene or ceramic, with a single layer thickness controlled at 1–3 cm to avoid stacking and heavy pressure; push the tray into the pulse high-voltage processing chamber, close the door and seal it; adjust the parallel plate electrode system so that the distance between the upper and lower electrodes is 5–15 cm, ensuring that the medicinal materials are in a region with a uniform electric field intensity distribution; start the high-voltage pulse power supply, setting the output parameters to electric field intensity 20–40 kV / cm, pulse frequency 50–200 Hz, pulse width 2–5 μs, and pulse waveform as follows. Square wave or exponentially decaying wave; under ambient temperature of 20–25℃ and relative humidity of 40%–60%, a high-voltage pulse is continuously applied to the medicinal material for 10–20 minutes; during this process, the electric field acts on the inside of the medicinal material tissue, causing a transmembrane potential difference across the cell membrane. When the critical threshold is exceeded, irreversible electroporation is triggered, forming nanoscale micropore channels on the cell membrane and cell wall; after the treatment, the high-voltage power supply is turned off, the treatment chamber door is opened, the tray is taken out, and there are no obvious charring or carbonization marks on the surface of the medicinal material, maintaining its original color and shape.

[0018] By integrating an insulated porous tray made of polytetrafluoroethylene or ceramic, parallel plate high-voltage electrodes with adjustable spacing (5–15 cm), a high-voltage pulse power supply with programmable output parameters (electric field strength 20–40 kV / cm, frequency 50–200 Hz, pulse width 2–5 μs), and a temperature and humidity monitoring unit (20–25℃, 40%–60% RH), the workflow applies microsecond-level high-voltage pulses to a single layer of flat-laid medicinal materials at room temperature for 10–20 minutes. This causes the cell membrane to form irreversible nanoscale micropores due to the transmembrane potential exceeding the threshold, achieving the effect of significantly reducing cell wall mass transfer resistance and constructing physical channels for rapid water migration without producing charring or carbonization.

[0019] Example 4 After pulsed high-pressure treatment, the medicinal materials are transferred to stainless steel trays, arranged in a single layer, and placed into a vacuum drying oven with a programmable control system. The oven door is closed and the vacuum system is activated. A rotary vane vacuum pump gradually reduces the pressure inside the oven from atmospheric pressure to -0.08 MPa to -0.095 MPa, maintaining this negative pressure for 10–15 minutes. This allows the air in the interstitial spaces of the medicinal materials to expand due to the pressure reduction and escape through the micropores. The vacuum pump is then turned off, and the inlet valve is slowly opened to introduce air filtered through a 0.22 μm membrane into the oven. Use filtered, dry compressed air or high-purity nitrogen to restore the pressure inside the chamber to atmospheric pressure. This process should be completed within 2–5 minutes. After the pressure is balanced, start the vacuum pump again for a second vacuuming. Repeat the above "vacuuming-gas return" cycle a total of 3–5 times. During each cycle, the entry and exit of gas creates a dynamic pressure difference inside the medicinal material, which promotes further expansion of the intercellular spaces and displaces residual gas, creating a low-resistance path for subsequent moisture migration. After the last gas return is completed, maintain the chamber at atmospheric pressure to prepare for the next drying stage.

[0020] By employing a combination of a stainless steel material tray, a vacuum drying oven with pressure sensors and PLC control, a rotary vane vacuum pump (ultimate vacuum ≤ -0.095 MPa), a dry air / nitrogen inlet valve filtered by a 0.22 μm sterilization filter, and an automatic pressure balancing system, the workflow executes 3–5 cycles of “vacuuming (-0.08 to -0.095 MPa, 10–15 min) – slow gas return (2–5 min)”. The periodic pressure difference drives the gas to repeatedly enter and exit through the formed micropores, achieving the effects of further expanding the intercellular spaces, replacing residual air inside, and reducing the vapor diffusion resistance during subsequent drying processes.

[0021] Example 5 After drying, turn off the heating and fan systems. Once the temperature inside the chamber has naturally dropped to room temperature, remove the medicinal materials from the material tray and place them into a sealed food-grade polyethylene or stainless steel container with a lid. Do not add any desiccant or filler to the container. The stacking height of the medicinal materials should not exceed 30cm. Place the container in a constant temperature and humidity room with a temperature of 20–25℃ and a relative humidity of 50%–60% and let it stand for 24–48 hours. During this period, spontaneous diffusion will occur inside the medicinal materials due to the existence of a moisture gradient. Moisture in high moisture content areas will migrate to low moisture content areas, eventually achieving a more uniform overall moisture distribution. After the softening process, the medicinal materials will feel soft and pliable to the touch, without obvious brittleness or localized dampness.

[0022] By using food-grade polyethylene or stainless steel sealed containers (with the stacking height of medicinal materials ≤30cm) in conjunction with a temperature and humidity controlled (20–25℃, 50%–60%RH) constant temperature and humidity storage room, the workflow involves letting the herbs stand for 24–48 hours after drying. This utilizes the moisture gradient existing inside the herbs to drive water molecules to spontaneously diffuse from high humidity areas to low humidity areas, thereby eliminating the "dry outside, wet inside" phenomenon, reducing the standard deviation of the moisture content of the entire batch of medicinal slices to below 1.2%, and improving the flexibility of the medicinal slices and the consistency of dissolution during subsequent decoction.

[0023] Example 6 The softened medicinal slices are laid flat on a conveyor belt and sent into an ultraviolet sterilization chamber. They are irradiated with a low-pressure mercury lamp array with a wavelength of 254nm, an irradiation intensity of 50–100μW / cm², and a treatment time of 5–10 minutes. Alternatively, a low-temperature ozone generator is used, and ozone gas with a concentration of 5–10mg / L is introduced to fumigate in a sealed chamber for 15–20 minutes. After sterilization, the medicinal slices are weighed according to specifications and packed into aluminum foil composite bags or aluminized film bags. A vacuum packaging machine is used to evacuate the bags until the residual pressure is ≤-0.09MPa, and then the bags are heat-sealed. Alternatively, a nitrogen-filling packaging machine is used to inject nitrogen gas with a purity of ≥99.9% to a positive pressure of 0.02–0.05MPa inside the bag and then seal it. The packaged products are labeled and stored in a cool, dry place.

[0024] By integrating a 254nm low-pressure mercury lamp array (irradiance 50–100μW / cm²) or a low-temperature ozone generator (output concentration 5–10mg / L), aluminum foil composite / aluminized film packaging bags, intelligent weighing system, vacuum packaging machine (residual pressure ≤-0.09MPa) or nitrogen-filled packaging machine (injecting N2 purity ≥99.9% to a positive pressure of 0.02–0.05MPa), the workflow completes surface microbial inactivation and implements high-barrier sealing under non-thermal conditions, achieving the hygiene standard of total aerobic bacteria <10³CFU / g and mold and yeast <10²CFU / g. At the same time, it effectively isolates oxygen and moisture, extends the shelf life of medicinal slices, and maintains the stability of active ingredients such as volatile oils and saponins.

[0025] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention. The scope of protection claimed by the appended claims and their equivalents is defined.

Claims

1. A method for pre-treatment and drying of Gui Shiwei traditional Chinese medicine slices based on pulsed high voltage, comprising the following steps: Step 1: Raw material cleaning and grading pretreatment. Remove impurities and non-medicinal parts from the harvested Gui Shi Wei Chinese medicinal materials. Use running pure water to quickly wash the mud and dust off the surface of the medicinal materials. Grade the medicinal materials according to their texture and shape. Step 2: Pulsed high-voltage electric field treatment. The pre-treated medicinal materials are spread flat on an insulating porous tray and placed in the pulsed high-voltage treatment chamber. Step 3: Vacuum pulsed permeation, transferring the medicinal materials after pulsed high-pressure treatment to the material tray inside the vacuum drying oven; Step 4: Variable temperature combined drying, using a segmented variable temperature drying process to dehydrate and dry the medicinal materials; Step 5: Softening and Moistening. After drying, remove the medicinal materials and place them in a sealed container. Let them stand at room temperature for 24-48 hours. Step Six: Sterilization and Packaging. The softened medicinal slices are then subjected to ultraviolet sterilization or low-temperature ozone sterilization again, followed by vacuum packaging or nitrogen-filled packaging according to pharmacopoeia standards to obtain the finished product.

2. The method for pretreatment and drying of Gui Shiwei traditional Chinese medicine slices based on pulsed high voltage according to claim 1, characterized in that, The harvested medicinal herbs, including cinnamon, monk fruit, star anise, turmeric, longan pulp, sophora root, chicken blood vine, chicken bone grass, thorny thorn, and earthworm, are placed on a clean workbench. They are manually selected to remove mud, stones, insect-damaged parts, moldy parts, and other non-medicinal components. The herbs are then transferred to a washing tank and rinsed with room-temperature purified water at a flow rate of 0.5–1.0 m / s for 2–5 minutes to wash away dust, impurities, and some microorganisms. After washing, the herbs are classified according to their botanical parts and physical characteristics: rhizomes such as sophora root, thorny thorn, chicken blood vine, and turmeric, and whole herbs such as chicken bone grass, are processed using stainless steel cutting tools. The slicer cuts the herbs into oblique slices 2–5 mm thick or segments 1–3 cm long. For fruit-based herbs, monk fruit can be kept whole or split open along the equator to remove the seeds. Longan pulp needs to have its outer shell removed and the pit removed. Star anise is kept intact or broken into single petals according to subsequent processing requirements. For bark-based herbs such as cinnamon and cassia branches, the rough outer bark is first scraped off with a bamboo knife, then rolled into a tube or cut into small square pieces of 2–4 cm. For animal-based herbs such as earthworm, the herbs are longitudinally split along the midline of the abdomen, and the internal organs are removed with a soft brush and rinsed repeatedly with clean water until the body cavity is clean. All processed herbs are laid flat on a food-grade plastic screen and allowed to air dry naturally in a ventilated room for 10–30 minutes, allowing surface moisture to drip off, forming the material to be processed.

3. The method for pretreatment and drying of Gui Shiwei traditional Chinese medicine slices based on pulsed high voltage according to claim 1, characterized in that, The drained medicinal materials are evenly spread on an insulating porous tray made of polytetrafluoroethylene or ceramic, with the thickness of a single layer controlled at 1–3 cm to avoid stacking and heavy pressure; the tray is pushed into the pulse high-voltage treatment chamber, the door is closed and sealed; the parallel plate electrode system is adjusted so that the distance between the upper and lower electrodes is 5–15 cm to ensure that the medicinal materials are in a region with a uniform electric field intensity distribution. Turn on the high-voltage pulse power supply and set the output parameters as follows: electric field strength 20–40 kV / cm, pulse frequency 50–200 Hz, pulse width 2–5 μs, and pulse waveform as square wave or exponentially decaying wave. Under the conditions of ambient temperature 20–25℃ and relative humidity 40%–60%, continuously apply high-voltage pulses to the medicinal materials for 10–20 minutes. During this process, the electric field acts on the inside of the medicinal material tissue, causing a transmembrane potential difference across the cell membrane. When the critical threshold is exceeded, irreversible electroporation is triggered, forming nanoscale microporous channels on the cell membrane and cell wall. After the treatment is completed, turn off the high-voltage power supply, open the treatment chamber door, and remove the tray. The surface of the medicinal materials shows no obvious charring or carbonization marks and retains its original color and shape.

4. The method for pretreatment and drying of Gui Shiwei traditional Chinese medicine slices based on pulsed high voltage according to claim 1, characterized in that, The medicinal materials, after being treated with pulsed high pressure, are transferred to stainless steel material trays, arranged in a single layer, and then placed into a vacuum drying oven equipped with a programmable control system. The oven door is closed and the vacuum system is activated. A rotary vane vacuum pump gradually reduces the air pressure inside the oven from atmospheric pressure to -0.08 MPa to -0.095 MPa, maintaining this negative pressure for 10–15 minutes. This allows the air in the interstitial spaces of the medicinal materials to expand due to the pressure reduction and escape through the micropores. Subsequently, the vacuum pump is turned off, and the inlet valve is slowly opened to introduce air into the oven through a 0.22 μm filter membrane. Filtered dry compressed air or high-purity nitrogen is used to restore the pressure inside the chamber to atmospheric pressure. This process should be completed within 2–5 minutes. After the pressure is balanced, the vacuum pump is restarted for a second vacuuming operation. The above "vacuuming-gas return" cycle is repeated a total of 3–5 times. During each cycle, the entry and exit of gas creates a dynamic pressure difference inside the medicinal material, which promotes further expansion of the intercellular spaces and displaces residual gas, creating a low-resistance path for subsequent moisture migration. After the last gas return is completed, the chamber is kept at atmospheric pressure to prepare for the next drying stage.

5. The method for pretreatment and drying of Gui Shiwei traditional Chinese medicine slices based on pulsed high voltage according to claim 1, characterized in that, After the drying process is complete, turn off the heating and fan systems. Once the temperature inside the chamber has naturally dropped to room temperature, remove the medicinal materials from the material tray and place them into a sealed food-grade polyethylene or stainless steel container with a lid. Do not add any desiccant or filler to the container. The height of the medicinal materials should not exceed 30cm. Place the container in a constant temperature and humidity room with a temperature of 20–25℃ and a relative humidity of 50%–60% and let it stand for 24–48 hours. During this period, spontaneous diffusion will occur inside the medicinal materials due to the existence of a moisture gradient. Moisture in high moisture content areas will migrate to low moisture content areas, eventually achieving a uniform overall moisture distribution. After the softening process is complete, the medicinal materials will feel soft and pliable, without obvious brittleness or localized dampness.

6. The method for pretreatment and drying of Gui Shiwei traditional Chinese medicine slices based on pulsed high voltage according to claim 1, characterized in that, The softened medicinal slices are laid flat on a conveyor belt and sent into an ultraviolet sterilization chamber. They are irradiated with a low-pressure mercury lamp array at a wavelength of 254 nm, with an irradiation intensity of 50–100 μW / cm², for 5–10 minutes. Alternatively, a low-temperature ozone generator is used, introducing ozone gas at a concentration of 5–10 mg / L, and fumigating in a sealed chamber for 15–20 minutes. After sterilization, the medicinal slices are weighed according to specifications and packed into aluminum foil composite bags or aluminized film bags. A vacuum packaging machine is used to evacuate the bags until the residual pressure is ≤-0.09 MPa, then heat-sealing is performed. Alternatively, a nitrogen-filling packaging machine is used to inject nitrogen gas with a purity ≥99.9% to a positive pressure of 0.02–0.05 MPa inside the bag before sealing. The packaged products are labeled and stored in a cool, dry place.