Processing method of stems and leaves of pilea japonica and pilea japonica scented tea

Abstract

The invention discloses a processing method of stems and leaves of pilea japonica and pilea japonica scented tea. The method comprises the following steps: harvesting stems and leaves 10 cm above the ground in the earlier stage of flowering; after cleaning and slitting, carrying out two-stage fixation at 70 DEG C and 50 DEG C; softening at the temperature of 40 DEG C and the RH of 70%, and adding the wolfberry powder and the ginger juice; carrying out spraying treatment for 5 minutes by using a 0.1% cellulase solution, and rolling by using a silica gel coated roller until the wall breaking rate is 80%; heating and drying at the temperature of 50 DEG C, 55 DEG C and 45 DEG C until the water content is 8 + / -0.5%; and finally, spraying vitamin C or chitosan to form a film, and carrying out vacuum nitrogen-filled packaging. The retention rate of flavone and polysaccharide of the prepared eriocheir sinensis flower tea is larger than or equal to 92%, the retention rate of volatile oil is larger than or equal to 90%, the leaching rate is increased by 30% or above, the retention rate of main components is larger than or equal to 90% after the eriocheir sinensis flower tea is stored for 24 months at normal temperature, and the problems that in the prior art, the retention rate of components is low, leaching is difficult, and the storage period is short are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of traditional Chinese medicine processing. More particularly, the present application relates to a processing method of stems and leaves of Lysimachia foenum-gracum Hance and a Lysimachia foenum-gracum Hance tea. BACKGROUND

[0002] Lysimachia foenum-gracum Hance is a perennial herbaceous medicinal plant, which is commonly used as a medicinal and edible plant in local folk. It is often used for medicinal tea, medicinal diet and health care. The stems and leaves of Lysimachia foenum-gracum Hance are rich in flavonoids, chlorogenic acid, polysaccharides and volatile oil and other active ingredients, and have high medicinal and edible value.

[0003] At present, the traditional processing method of Lysimachia foenum-gracum Hance is mostly direct drying after harvesting, or drying treatment after simple steaming. However, these existing processing methods have the following obvious defects: Firstly, the harvesting period and position are not accurate. Traditional harvesting is mostly concentrated in the flowering period, and the inflorescence is mainly used as medicine, ignoring the characteristics that the active ingredient content in stems and leaves reaches the peak before flowering, resulting in low background content of effective components of medicinal raw materials, which directly affects the internal quality of the final product.

[0004] Secondly, the retention rate of active ingredients is low. In traditional processing, long-time high-temperature fixation or open-air sunning is often used. This rough processing method easily leads to oxidation and degradation of heat-sensitive and light-sensitive components such as flavonoids and chlorogenic acid, and a large amount of volatile oil components are lost, resulting in weakening of the aroma of medicinal materials and decline of medicinal effect.

[0005] Thirdly, the medicinal ingredients are difficult to leach out. Lysimachia foenum-gracum Hance stems and leaves are rich in cellulose and hemicellulose, and have a dense tissue structure. The existing processing technology does not specifically perform cell wall breaking treatment, so that the cell wall is difficult to break during brewing or decoction, the effective component dissolution rate is low, and the full play of the medicinal effect is limited.

[0006] In addition, the storage stability is poor. The traditional dried Lysimachia foenum-gracum Hance lacks effective oxidation and moisture prevention treatment, and is prone to problems such as discoloration, loss of aroma, and decrease of effective ingredient content during storage, resulting in short shelf life of medicinal materials, which is difficult to meet the needs of commercial circulation and long-term use.

[0007] In summary, the existing processing technology of Lysimachia foenum-gracum Hance has the problems of unscientific harvesting, low component retention rate, insufficient release of medicinal effect, short storage period, unstable quality of medicinal materials, etc., and it is urgent to develop a scientific and controllable processing technology of Lysimachia foenum-gracum Hance stems and leaves suitable for industrial production. SUMMARY

[0008] An object of the present application is to solve at least the above problems and to provide at least the advantages described later.

[0009] In order to achieve these objects and other advantages according to the present application, a processing method of Lysimachia foenum-gracum Hance stems and leaves is provided, comprising the following steps: a. Harvesting and pretreatment: Before the flowering period of *Hymenoplastes pubescens*, harvest the stems and leaves above 10 cm from the ground, discard the lignified basal section, and after washing and cutting, obtain the pretreated stems and leaves; b. Two-stage blanching: The pretreated stems and leaves are subjected to high-temperature blanching and low-temperature aroma preservation softening in sequence; the high-temperature blanching is to raise the temperature to 65~75℃ and hold it for 20~40 seconds, and then cool it down; the low-temperature aroma preservation softening is to treat at 45~55℃ for 10~20 minutes. c. Softening: The stems and leaves after blanching are softened and mixed with medicinal property regulating excipients; d. Enzyme-assisted cell wall breaking: Spray cellulase solution onto the softened stems and leaves for enzymatic hydrolysis, and then roll them to break the cell walls. e. Programmed temperature drying: The stems and leaves after cell wall disruption are dried under gradient temperature control. The first stage removes surface moisture, the second stage removes free water between cells, and the third stage is dried at low temperature to constant weight. f. Oxygen-proof encapsulation and packaging: Spray food-grade antioxidant film-forming solution onto the surface of dried stems and leaves to form a protective layer, and then air-dry and vacuum-packed with nitrogen.

[0010] Preferably, the cleaning in step a includes: rinsing with running water first, and then soaking in 0.5% saline solution for 1 minute; the cutting involves cutting the stem into 3-5cm segments while keeping the leaves intact.

[0011] Preferably, in step b: The high-temperature sterilization process uses steam or infrared heating to raise the temperature to 70°C and maintain it for 30 seconds, then cools it down to 50°C. The low-temperature aroma preservation and softening process involves treating the stems and leaves with 50°C hot air or swirling air for 12-15 minutes, during which the stems and leaves are continuously turned over, and the humidity of the hot air is controlled at 50-60%RH.

[0012] Preferably, the conditions for the softening treatment in step c are: temperature 40℃, humidity 70%RH, and time 20 minutes; the medicinal property regulating excipients are 0.5% wolfberry powder and 0.5% ginger juice by weight of stems and leaves, which are mixed in by spraying.

[0013] Preferably, in step d: the concentration of the cellulase solution is 0.1%, the spraying amount is 0.1% ± 0.02% of the stem and leaf weight, and the enzymatic hydrolysis time is 5 ± 1 minutes; the rolling treatment is carried out using a silicone-coated roller to achieve a stem and leaf cell wall breakage rate of 80%.

[0014] Preferably, the programmed heating and drying in step e specifically involves: First stage: constant temperature treatment at 50℃ for 12 minutes; Second stage: constant temperature treatment at 55℃ for 25 minutes; Third stage: Dry at a constant temperature of 45℃ until the moisture content of the stems and leaves reaches 8±0.5%.

[0015] Preferably, the food-grade antioxidant film-forming solution in step f is a 0.05% vitamin C solution or a 0.1% chitosan solution, and the thickness of the film formed does not exceed 50 micrometers; the packaging is vacuum nitrogen-filled dispensing using aluminum foil light-shielding material.

[0016] The present invention also provides a tea or slices of *Rhizophora flavescens* prepared using the above-described processing method.

[0017] The present invention has at least the following beneficial effects: High retention rate of active ingredients and significantly improved quality of medicinal materials: This invention precisely targets the harvest window before flowering, ensuring that active ingredients such as flavonoids, chlorogenic acid, and polysaccharides in the stems and leaves are at their peak, thus guaranteeing the quality of raw materials from the source. Simultaneously, a two-stage blanching process is employed: first, polyphenol oxidase and chlorophyllase are rapidly inactivated at 70℃ to prevent enzymatic oxidation of components; then, aroma preservation and softening are achieved at 50℃, avoiding the loss of volatile oils. Testing shows that the finished product of this invention retains ≥92% of flavonoids, ≥85% of chlorogenic acid, ≥90% of volatile oils, and ≥93% of polysaccharides, with an overall degradation rate of less than 5% for active ingredients, significantly superior to traditional sun-drying or high-temperature drying processes.

[0018] Significantly Improved Extraction Efficiency of Medicinal Components: This invention innovatively introduces enzyme-assisted rolling cell wall disruption technology, specifically targeting the characteristics of the stems and leaves of *Anemarrhena asphodeloides*, which are rich in cellulose and have dense cell walls. By selectively degrading the cellulose components in the cell walls with a 0.1% cellulase solution, combined with the gentle physical compression of a silicone-coated roller, the cell wall disruption rate of the stems and leaves reaches approximately 80%. This technology effectively destroys the cell wall structure that hinders component dissolution while preserving the integrity of the leaves, increasing the extraction efficiency of medicinal components by more than 30% compared to traditional processes, ensuring that the medicinal efficacy is fully realized during brewing or decoction.

[0019] High storage stability and significantly extended shelf life: This invention adds an oxygen-proof encapsulation step after drying, forming a thin protective layer no more than 50 micrometers thick on the surface of the stems and leaves by spraying with 0.05% vitamin C solution or 0.1% chitosan solution, effectively isolating oxygen and moisture. Combined with vacuum nitrogen-filled packaging and aluminum foil light-shielding material, a multi-layered protection system is constructed. Experiments have shown that after 24 months of storage at room temperature, the content of the main active ingredients in the processed medicinal herbs remains above 90% of the pre-storage content, with no significant changes in color or aroma, resulting in a significantly extended shelf life compared to traditionally dried medicinal materials.

[0020] With outstanding medicinal and edible value and improved palatability, this invention sprays in 0.5% wolfberry powder and 0.5% ginger juice during the conditioning and softening step. On the one hand, this aligns with the traditional processing concept of "conditioning" in She ethnic medicine, appropriately adjusting the cold properties of the herb. On the other hand, the sweetness of wolfberry and the spiciness of ginger synergistically improve the flavor and taste of the herb, making it more suitable for use as a substitute tea or medicinal food ingredient, thus broadening the application scenarios of the product.

[0021] Good industrial adaptability: The entire process parameters are clear and highly controllable, and can be directly applied to large-scale production lines.

[0022] Other advantages, objectives and features of the present invention will become apparent in part from the following description, and in part from those skilled in the art through study and practice of the invention. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to embodiments, so that those skilled in the art can implement it based on the description.

[0024] It should be noted that, unless otherwise specified, the experimental methods described in the following implementation plan are all conventional methods, and the reagents and materials described are all commercially available unless otherwise specified.

[0025] <Example 1> A method for processing the stems and leaves of *Anemarrhena asphodeloides* includes the following steps: a. Harvesting and Pre-treatment: Harvesting time: Choose a sunny morning between 9 and 11 am, when the flowers of the herb are in the early stage of blooming (before the flower buds are fully open); Harvesting method: Cut the stems and leaves above 10 cm from the ground and discard the lignified basal section; Raw material pretreatment: Remove insect-infested leaves, withered leaves, and dirt and impurities; rinse quickly with running water to remove dirt and sand adhering to the surface of stems and leaves; soak in 0.5% saline solution for 1 minute to reduce microbial adhesion and close the surface cells. Cutting specifications: Cut the stem into 3-5cm sections, while keeping the leaves intact.

[0026] b. Two-stage wrap-up: High-temperature sterilization: Spread the stems and leaves evenly, and use steam or infrared heating to quickly raise the temperature to 70°C, hold for 30 seconds, and then cool down to 50°C. Low-temperature aroma preservation and softening: Treat with 50℃ hot air or swirling air for 12-15 minutes, turning continuously during the process, to achieve simultaneous softening of stem fibers and preservation of aroma and active ingredients.

[0027] c. Softening of tone: After blanching, place the stems and leaves in a 40℃ constant temperature and humidity chamber for 20 minutes to soften (ambient humidity 70%RH). Spray with 0.5% wolfberry powder and 0.5% ginger juice to adjust the cold properties of the medicine and improve palatability.

[0028] d. Enzyme-assisted cell disruption: Spray with 0.1% cellulase solution for 5 minutes to partially degrade the cell wall structure; use a silicone-coated roller to roll and press the stems and leaves to achieve a cell wall breakage rate of about 80%, while retaining some leaf morphology.

[0029] In actual production, operators can judge whether the "rolling" is in place by the following methods: the leaves are basically intact, without obvious breakage, the edges are slightly curled, the stem segments are flat but not broken, the fibers are loose and visible but not broken, there is a slight sandy feeling when rubbing (the sound of cell breaking), but no powdery feeling, and when the sample is taken for microscopic observation, the cell wall is broken to 70-85%, and when steeped in hot water for 5 minutes, the soup color is significantly darker (compared to the unbroken sample).

[0030] e. Programmed heating and drying: Following the principle of "gradient temperature control, fast at first and then stable", the drying process is carried out in three stages: First stage: constant temperature treatment at 50℃ for 12 minutes to remove free surface moisture; Second stage: constant temperature treatment at 55℃ for 25 minutes to remove free water between cells; The third stage: dry at a constant temperature of 45℃ until the moisture content of the stems and leaves reaches 8±0.5%, completing the final drying process.

[0031] f. Oxygen-proof encapsulation and packaging: After drying, spray with 0.05% vitamin C solution or 0.1% chitosan solution to form a thin protective film on the surface of stems and leaves. The film thickness should not exceed 50 micrometers to delay the oxidation of active ingredients. After air drying, the product is packaged using a vacuum nitrogen-filling process and light-blocking aluminum foil. It comes in two sizes: 15-30g / packet of medicinal food and 3-5g / packet of medicinal slices.

[0032] <Comparative Example 1> Traditional sun-drying method, process steps: Harvesting: Harvest the whole plant, including the inflorescence and the woody stem at the base, during the flowering period; Pretreatment: Rinse with clean water and air dry the surface moisture naturally; Cutting: Cut the whole plant into segments of varying lengths, 3-8cm. Drying: Expose to direct sunlight for 3 days, turning occasionally during the process, until the moisture content is approximately 10%. Packaging: Sealed in ordinary plastic bag, store at room temperature.

[0033] <Comparative Example 2> Traditional steaming and drying method, process steps: Harvesting: Harvest the stems and leaves at the initial flowering stage, 10cm or more above the ground; Pretreatment: Rinse with clean water and drain; Blanching: Steam for 5 minutes with boiling water. Drying: Dry in an 80℃ hot air drying oven for 4 hours until the moisture content is 9%; Packaging: Aluminum foil bag with ordinary seal, store at room temperature.

[0034] Comparative Example 3 (Comparison of Harvesting Timing) Process steps: Except for adjusting the harvesting time to the peak flowering period (when the flowers are fully open), the other steps are exactly the same as in Example 1 of this invention.

[0035] <Comparative Example 4> (Single-stage filming completion) Process steps: The two-stage blanching process was cancelled and replaced with blanching at a constant temperature of 60°C for 15 minutes (to both inactivate enzymes and dry the product). The remaining steps are exactly the same as in Example 1 of this invention.

[0036] <Comparative Example 5> (High-temperature blanching + no cooling) Process steps: The two-stage blanching process is changed to 70℃ steam blanching, and then the process proceeds directly to the next step (without 50℃ low-temperature aroma preservation and softening). The remaining steps are exactly the same as in Example 1 of this invention.

[0037] Comparative Example 6 (Enzyme-free cell disruption) Process steps: The step of "spraying 0.1% cellulase solution" is omitted, and only the silicone-coated roller rolling treatment is performed. The remaining steps are exactly the same as in Example 1 of this invention.

[0038] Comparative Example 7 (Physical kneading and cell wall breaking only) Process steps: The enzyme treatment and rolling roller were removed, and the traditional hand kneading was replaced with 5 minutes (simulating the processing technology of some substitute teas). The remaining steps were basically the same as those in Example 1 of this invention.

[0039] Comparative Example 8 (without anti-oxidation encapsulation) Process steps: The step of "spraying 0.05% vitamin C solution" is omitted. After drying, the product is directly vacuum-packed with nitrogen. The remaining steps are exactly the same as in Example 1 of this invention.

[0040] Comparative Example 9 (Standard Packaging) The oxygen-proof encapsulation and vacuum nitrogen filling are omitted, and ordinary sealed packaging with aluminum foil bags is used. The remaining steps are exactly the same as in Embodiment 1 of this invention.

[0041] <Determination of Flavonoid Retention Rate> Preparation of reference solution: Accurately weigh an appropriate amount of rutin reference standard, dissolve it in methanol and dilute to volume to prepare a reference solution containing 0.2 mg per 1 mL.

[0042] Preparation of test solution: Take about 1.0 g of powdered *Anthopogon japonicus* (passed through a No. 3 sieve), accurately weigh it, place it in a stoppered conical flask, accurately add 25 mL of 70% ethanol, stopper tightly, weigh it, sonicate (power 250 W, frequency 40 kHz) for 30 min, cool it, weigh it again, replenish the lost weight with 70% ethanol, shake well, filter it, and collect the filtrate to obtain the test solution.

[0043] Determination method: Accurately measure an appropriate amount of the test solution and place it in a 25 mL volumetric flask. Using the NaNO2-Al(NO3)3-NaOH colorimetric method, add 1.0 mL of 5% sodium nitrite solution sequentially, shake well, and let stand for 6 min; add 1.0 mL of 10% aluminum nitrate solution, shake well, and let stand for 6 min; add 10.0 mL of 4% sodium hydroxide solution, add water to the mark, shake well, and let stand for 15 min. Using the corresponding reagent as a blank, measure the absorbance at a wavelength of 510 nm. Simultaneously, accurately measure the reference solution and perform colorimetric determination using the same method. The retention rate of flavonoid components is calculated according to the following formula: Flavonoid retention rate (%) = (Flavor content of the sample after processing / Flavonoid content of the fresh sample before processing) × 100% In the formula, the flavonoid content of the fresh product before processing is based on the value measured after freeze-drying of fresh medicinal herbs, stems and leaves from the same batch.

[0044] <Chronic Acid Retention Rate Determination> Chromatographic conditions: High-performance liquid chromatography (HPLC) was used. Column: Kromasil C 18 Column (250 mm × 4.6 mm, 5 μm); mobile phase: acetonitrile-0.4% phosphoric acid solution (20:80); detection wavelength: 324 nm or 327 nm; flow rate: 1.0 mL·min -1 Column temperature: 25℃; Injection volume: 10μL.

[0045] Preparation of reference solution: Accurately weigh an appropriate amount of chlorogenic acid reference standard, dissolve it in methanol and dilute to volume to prepare a reference solution containing 40 μg per 1 mL.

[0046] Preparation of test solution: Take about 0.5g of powdered *Anthopogon japonicus* (passed through a No. 3 sieve), accurately weigh it, place it in a stoppered conical flask, accurately add 25mL of 50% methanol, stopper tightly, weigh it, sonicate for 30min, cool it, weigh it again, replenish the lost weight with 50% methanol, shake well, filter it, and take the filtrate to obtain the test solution.

[0047] Determination method: Accurately pipette 10 μL each of the test solution and the reference solution into the liquid chromatograph, measure the peak area, and calculate the chlorogenic acid content using the external standard method. The retention rate of chlorogenic acid is calculated using the following formula: Chlorogenic acid retention rate (%) = (Chlorogenic acid content of the sample after processing / Chlorogenic acid content of the fresh sample before processing) × 100% In the formula, the chlorogenic acid content of the fresh product before processing is based on the value measured after freeze-drying of fresh medicinal herbs, stems and leaves from the same batch.

[0048] <Determination of the Retention Rate of Volatile Oil Components> Volatile oil extraction: Refer to General Chapter 2204, Determination of Volatile Oils, of the Chinese Pharmacopoeia (2020 Edition). Accurately weigh approximately 100g of the *Hymenochloa crus-galli* flower sample and place it in a volatile oil analyzer. Add 500mL of water and several glass beads. Connect the volatile oil analyzer to the reflux condenser. Add water from the top of the condenser until it fills the graduated section of the volatile oil analyzer and overflows into the flask. Place the flask in a heating mantle and slowly heat to boiling, maintaining a gentle boil for 5 hours, until the oil level in the analyzer no longer increases. Stop heating and let stand for at least 1 hour before reading the volatile oil content.

[0049] Calculation of volatile oil content: Volatile oil content (mL / 100g) = Volatile oil volume (mL) / Sample weight (g) × 100 Volatile oil component analysis: An appropriate amount of the extracted volatile oil was dehydrated with anhydrous sodium sulfate and then analyzed by gas chromatography-mass spectrometry (GC-MS). Chromatographic conditions: HP-5MS capillary column (30m × 0.25mm, 0.25μm); Temperature program: initial temperature 60℃, hold for 2 min, increase to 120℃ at 5℃·min⁻¹, then increase to 250℃ at 10℃·min⁻¹, hold for 10 min; Injector temperature 250℃; Carrier gas: high-purity helium; Flow rate 1.0 mL·min⁻¹. -1 Split ratio 20:1; injection volume 1 μL. Mass spectrometry conditions: EI ion source, electron energy 70 eV, ion source temperature 230℃, quadrupole temperature 150℃, scan range m / z 35-500. Major volatile oil components were identified by searching the NIST spectral library, and the relative content of each component was calculated using the peak area normalization method.

[0050] Volatile oil retention rate (%) = (Volatile oil content of the sample after processing / Volatile oil content of the fresh product before processing) × 100% In the formula, the volatile oil content of the fresh product before processing is based on the value measured after freeze-drying of fresh medicinal herbs, stems and leaves from the same batch.

[0051] <Determination of Polysaccharide Component Retention Rate> Preparation of reference solution: Accurately weigh 10 mg of glucose reference standard dried to constant weight at 105℃, place it in a 100 mL volumetric flask, add water to dissolve and dilute to the mark, shake well, and prepare a glucose reference solution containing 0.1 mg per mL.

[0052] Preparation of the test solution: Accurately weigh approximately 1.0 g of *Anthopogon japonicus* sample powder (passed through a No. 3 sieve), place it in a round-bottom flask, add 100 mL of water, heat under reflux for 2 hours, filter while hot, add 50 mL of water to the residue, heat under reflux for 1 hour, filter again, combine the filtrates, concentrate to approximately 10 mL, cool, add anhydrous ethanol to achieve an alcohol content of 80%, shake well, and refrigerate overnight. Centrifuge, discard the supernatant, dissolve the precipitate in hot water, transfer to a 50 mL volumetric flask, cool, add water to the mark, shake well, and the test solution is ready.

[0053] Preparation of standard curve: Accurately measure 0.2, 0.4, 0.6, 0.8, and 1.0 mL of glucose reference solution into stoppered test tubes, add water to bring the volume to 1.0 mL, accurately add 1.0 mL of 5% phenol solution to each tube, shake well, and then quickly and accurately add 5.0 mL of sulfuric acid. Shake well again, let stand for 10 min, and then incubate in a 40℃ water bath for 15 min. Remove from the water bath and quickly cool to room temperature. Using the corresponding reagent as a blank, measure the absorbance at a wavelength of 490 nm. Plot the standard curve with absorbance on the ordinate and glucose mass on the abscissa.

[0054] Determination method: Accurately measure 1.0 mL of the test solution, and follow the method under the preparation of the standard curve, starting from "add 1.0 mL of 5% phenol solution", and measure the absorbance. Read the mass of glucose in the test solution from the standard curve and calculate the polysaccharide content.

[0055] Polysaccharide retention rate (%) = (Polysaccharide content of the sample after processing / Polysaccharide content of the fresh sample before processing) × 100% In the formula, the polysaccharide content of the fresh product before processing is based on the value measured after freeze-drying of fresh anemone flowers, stems and leaves harvested in the same batch.

[0056] <Sensory Evaluation Methods> Based on the identification methods of medicinal materials in the Chinese Pharmacopoeia and the general principles of sensory evaluation of food, a sensory evaluation system for raw medicinal materials and processed medicinal products was established.

[0057] Evaluation personnel: A panel of 10 trained sensory evaluators (5 traditional Chinese medicine professionals and 5 tea evaluators) was formed.

[0058] Evaluation indicators and weights: Three indicators are set: color (30%), aroma (40%), and shape (30%), and a 100-point scoring system is used.

[0059] Evaluation criteria: as shown in the table below.

[0060] Evaluation method: The samples were coded and randomly presented to the evaluators. Each evaluator scored them independently, and the average score of each indicator was taken as the total sensory evaluation score.

[0061] <Methods for detecting cell wall breakage rate> Cell wall disruption rate was determined by combining microscopic observation with a specific component release method.

[0062] Microscopic observation method: Take an appropriate amount of Antherina sample, place it on a glass slide, add 1 drop of distilled water, cover with a coverslip, and observe under an optical microscope (10×40x). Randomly select 10 fields of view, count the number of cells with cell wall disruption and the total number of cells, and calculate the cell wall disruption rate according to the following formula: Microscopic cell wall disruption rate (%) = (Number of cells with disrupted cell walls / Total number of cells) × 100% Conductivity method: Accurately weigh 1.0 g of *Antheridae* sample and place it in a 100 mL beaker. Add 50 mL of distilled water and extract by stirring in a 25℃ constant temperature water bath for 10 min. Immediately filter with filter paper and measure the conductivity (μS·cm⁻¹) of the filtrate using a conductivity meter. Simultaneously, thoroughly grind the *Antheridae* sample to completely disrupt the cell wall and measure its conductivity using the same method as a control. Calculate the cell wall disruption rate using the following formula: Electrical conductivity cell wall breakage rate (%) = (Sample conductivity - Unbroken control standard conductivity) / (Completely broken control standard conductivity - Unbroken control standard conductivity) × 100% In the formula, the unbroken cell wall reference standard is a sample of fresh anther flower stems and leaves that have not undergone cell wall disruption treatment and have been freeze-dried.

[0063] The average of the results from the two methods was used as the final cell wall breakage rate.

[0064] <Leaching Rate Testing Methods> Refer to the method for determining the extracts of Chinese medicinal materials as specified in General Chapter 2201 of the Chinese Pharmacopoeia (2020 edition).

[0065] Determination of extractive efficacy: Accurately weigh 1.0 g of *Hymenoplastrus orbiculatus* flower sample, place it in a 250 mL Erlenmeyer flask, accurately add 100 mL of water, seal tightly, and soak in a boiling water bath for 30 min (simulating brewing conditions). Filter while hot. Determine the flavonoid content of the filtrate according to the method in <Determination of Flavonoid Retention Rate>, and record it as C1. Separately, take powder from the same batch, grind it thoroughly, and determine the total flavonoid content according to the aforementioned method, recording it as C0. Calculate the flavonoid extraction rate using the following formula: Flavonoid extraction rate (%) = C1 / C0 × 100% The chlorogenic acid leaching rate and polysaccharide leaching rate were determined using the same method, and the average value of the three was taken as the comprehensive leaching rate.

[0066] <Method for determining 24-month storage retention> Refer to the long-term stability test methods in the "Technical Guidelines for Stability Research of Traditional Chinese Medicine and Natural Drugs".

[0067] Sample storage: Take 3 batches of pilot-scale raw herb flower products, repackage them according to the intended market packaging (aluminum film vacuum nitrogen-filled packaging), and place them in a constant temperature and humidity chamber at a temperature of 25℃±2℃ and a relative humidity of 60%±10% to simulate normal temperature storage conditions.

[0068] Sampling time point: Samples were taken and tested at 24 months.

[0069] Testing indicators: After sampling at each time point, the flavonoid content was determined according to the aforementioned method, and sensory evaluation was performed according to the aforementioned method.

[0070] Content retention rate calculation: 24-month content retention rate of flavonoids (%) = (content of the component after 24 months of storage / content of the component after 0 months) × 100%.

[0071] <Results and Analysis> The test results of the examples and comparative examples are shown in the table below: Note: * indicates pre-storage testing data. The pre-storage data for Comparative Examples 8 and 9 are the same as those for Example 1. **The sensory scores before storage are compared with those of Example 1 in Comparative Examples 8 and 9. The leaching rate comparison is based on the flavonoid leaching rate of Example 1 (100%), and negative values ​​indicate the percentage lower than the benchmark.

[0072] The background content comparison between Comparative Example 3 (harvested at full bloom) and Example 1 is shown in the table below: The trends in component content changes in Examples 1, 8, and 9 after 24 months of storage are shown in the table below: I. The impact of harvesting time on the baseline quality of medicinal materials (Comparative Example 3) Comparative Example 3 used the exact same processing technique as Example 1, only the harvesting time was changed from the pre-flowering stage to the peak flowering stage. The results showed that the contents of major active ingredients such as flavonoids, chlorogenic acid, volatile oils, and polysaccharides in the anther stems and leaves harvested at the peak flowering stage were significantly lower than those in the pre-flowering stage, with a decrease of 2.6-8.5 percentage points. This result verifies the scientific validity of the invention's "precisely locking the pre-flowering harvesting window"—at this time, the accumulation of active ingredients in the stems and leaves reaches its peak, providing a high-quality raw material foundation for subsequent processing. Even with the most optimized processing techniques, the difference in raw material quality cannot be compensated for; therefore, precise control of the harvesting time is the primary prerequisite for ensuring the quality of the final product.

[0073] II. The effect of different blanching processes on component retention (Comparative Examples 1, 2, 4, and 5) 1. Traditional sun-drying method (Comparative Example 1) Comparative Example 1 used the traditional open-air sun-drying process, and the results showed extremely low retention rates of various components: flavonoids 61%, chlorogenic acid 53%, volatile oils 42%, and polysaccharides 67%. This is because prolonged exposure to sunlight caused photo-oxidative degradation of photosensitive components (such as flavonoids and chlorogenic acid), while high temperatures and contact with air accelerated the loss of volatile oils. The sensory score was only 62 points, with a dark brown color and a weak aroma, indicating that the traditional sun-drying method cannot meet the production requirements of high-quality raw medicinal herb tea.

[0074] 2. Traditional steaming and drying method (Comparative Example 2) Comparative Example 2, which involved steaming in boiling water for 5 minutes followed by drying at 80℃, showed improved component retention compared to sun-drying, but the volatile oil retention rate remained at only 51%. While the high temperature of the steam during steaming inactivated the oxidase to some extent, it also caused a significant loss of volatile components. The sensory score was 71 points, with a yellowish color and insufficient aroma, indicating that a single steaming process cannot simultaneously meet the dual requirements of enzyme inactivation and aroma preservation.

[0075] 3. Single-stage wrap-up (Comparative Example 4) Comparative Example 4 eliminated the two-stage blanching process and replaced it with a constant-temperature hot air blanching at 60℃ for 15 minutes. The results showed that the retention rates of flavonoids and chlorogenic acid were 83% and 76%, respectively, which were improved compared to Comparative Examples 1 and 2. However, the retention rate of volatile oil was only 72%, significantly lower than the 90.8% of Example 1. In the sensory evaluation, the color was dark yellow, the aroma was weak, and there was a slightly musty smell, indicating that although the constant-temperature treatment at 60℃ could partially inactivate enzymes, prolonged heating led to a serious loss of heat-sensitive volatile oils.

[0076] 4. No cooling after high-temperature blanching (Comparative Example 5) Comparative Example 5 proceeded directly to the next step after high-temperature blanching at 70℃, without undergoing low-temperature softening at 50℃. The results showed that the volatile oil retention rate further decreased to 68%, and the stem fibers were not sufficiently softened, resulting in a noticeably prickly feel when kneaded. This indicates that the lack of a low-temperature softening stage not only exacerbated the loss of volatile oils but also prevented the effective softening of the stem fiber structure, affecting subsequent cell wall breaking and the final product's texture.

[0077] 5. Synergistic advantages of two-stage wrap-up (Example 1) Example 1 employed a two-stage process: "70℃ high-temperature blanching for 30 seconds + 50℃ low-temperature softening and aroma preservation for 12-15 minutes." The high-temperature stage rapidly inactivates polyphenol oxidase and chlorophyllase, preventing enzymatic browning and component degradation; the low-temperature stage provides gentle treatment, fully softening the stem fibers while maximizing the retention of aromatic components such as volatile oils. Ultimately, the retention rates of flavonoids, chlorogenic acid, volatile oils, and polysaccharides reached 92.5%, 86.2%, 90.8%, and 93.1%, respectively, with a sensory score of 94 points, exhibiting a vibrant green color and rich aroma. This result fully demonstrates the effectiveness of the two-stage blanching technique, which combines rapid initial processing with slower slowing, balancing enzyme inactivation and aroma preservation, achieving a dual optimization of component retention and sensory quality.

[0078] III. The effect of cell wall disruption method on leaching efficiency (Comparative Examples 6 and 7) 1. Enzyme-free cell wall disruption (Comparative Example 6) Comparative Example 6 omitted cellulase treatment and only underwent silicone-coated roller pressing. The results showed that the cell wall breakage rate was only 52%, significantly lower than the 80% in Example 1; the leaching rate was 22% lower than in Example 1. This indicates that physical extrusion alone is insufficient to effectively disrupt the cellulose-rich cell wall structure, and the cell wall barrier cannot be fully opened, resulting in hindered dissolution of the active ingredients.

[0079] 2. Traditional hand-kneading (Comparative Example 7) Comparative Example 7 used traditional hand-kneading for 5 minutes instead of enzyme-assisted rolling to break down the cell walls. The results showed that the cell wall breaking rate was only 43%, and the extraction rate was 31% lower than that of Example 1. At the same time, the leaf morphology was severely damaged, and the sensory score was only 78 points. This indicates that the traditional kneading process has limited effect on breaking down the cell walls of stem and leaf medicinal materials and easily damages the integrity of the appearance, making it unsuitable for the production of high-quality raw medicinal herb tea.

[0080] 3. Synergistic advantages of enzyme-assisted rolling cell disruption (Example 1) Example 1 employed a combined process of "treatment with 0.1% cellulase solution for 5 minutes + rolling with a silicone-coated roller." Cellulase selectively degrades the cellulose components in the cell wall, softening the cell wall structure; the silicone-coated roller applies moderate pressure while protecting the leaf morphology. The synergistic effect of these two processes resulted in a cell wall disruption rate of 80%, with an extraction rate 22-31 percentage points higher than comparative examples 6 and 7, while maintaining good leaf morphology (sensory score of 94). This result validates the technical approach of synergistic cell wall disruption through "biochemical treatment + physical treatment," which not only solves the problem of difficult cell wall disruption in stem and leaf medicinal materials but also ensures the product's appearance and quality.

[0081] IV. The impact of storage technology on shelf life (Comparative Examples 8 and 9) 1. Encapsulation without oxygen protection (Comparative Example 8) Comparative Example 8 eliminated the vitamin C solution spraying step and directly applied vacuum nitrogen-filled packaging after drying. After 24 months of storage, the flavonoid retention rate was 82%, lower than the acceptable standard of 90%; the sensory score dropped to 78 points, the color became slightly darker, and the aroma weakened. This indicates that even with vacuum nitrogen-filled packaging, the lack of a surface film protective layer cannot completely inhibit the slow oxidation caused by residual oxygen inside the packaging, especially for easily oxidized components such as volatile oils.

[0082] 2. Standard packaging (Comparative Example 9) Comparative Example 9 simultaneously eliminated oxygen-proof encapsulation and vacuum nitrogen filling, using only a standard aluminum foil bag seal. After 24 months of storage, the flavonoid retention rate had decreased to 74%, the sensory score was 63 points, and there was significant fading, a weak aroma, and a slight stale smell. This demonstrates that conventional packaging is completely inadequate for long-term storage, validating the necessity of the multi-protection system of this invention.

[0083] 3. Synergistic advantages of oxygen-proof encapsulation + vacuum nitrogen filling (Example 1) Example 1 employs a triple protection system: "0.05% Vitamin C solution spray film formation + vacuum nitrogen-filled packaging + aluminum foil light shielding." The Vitamin C solution forms a thin protective film layer no more than 50 micrometers thick on the surface of the stems and leaves, effectively isolating oxygen and moisture; vacuum nitrogen filling further reduces the residual oxygen content inside the packaging; and the aluminum foil light shielding prevents photo-oxidation. The synergistic effect of these three factors ensures that the flavonoid retention rate of each major component is ≥90% after 24 months of storage, and the sensory score still reaches 91 points. This result fully demonstrates the advanced nature and reliability of the storage technology of this invention, providing technical assurance for achieving an ultra-long shelf life of 24 months for medicinal herb tea.

[0084] Although embodiments of the present invention have been disclosed above, they are not limited to the applications listed in the specification and embodiments. They can be applied to various fields suitable for the present invention. For those skilled in the art, other modifications can be easily made. Therefore, without departing from the general concept defined by the claims and their equivalents, the present invention is not limited to the specific details and embodiments shown and described herein.

Claims

1. A method for processing the stems and leaves of *Hymenoplastics*, characterized in that... Includes the following steps: a. Harvesting and pretreatment: Before the flowering period of *Hymenoplastes pubescens*, harvest the stems and leaves above 10 cm from the ground, discard the lignified basal section, and after washing and cutting, obtain the pretreated stems and leaves; b. Two-stage blanching: The pretreated stems and leaves are subjected to high-temperature blanching and low-temperature aroma preservation softening in sequence; the high-temperature blanching is to raise the temperature to 65~75℃ and hold it for 20~40 seconds, and then cool it down; the low-temperature aroma preservation softening is to treat at 45~55℃ for 10~20 minutes. c. Softening: The stems and leaves after blanching are softened and mixed with medicinal property regulating excipients; d. Enzyme-assisted cell wall breaking: Spray cellulase solution onto the softened stems and leaves for enzymatic hydrolysis, and then roll them to break the cell walls. e. Programmed temperature drying: The stems and leaves after cell wall disruption are dried under gradient temperature control. The first stage removes surface moisture, the second stage removes free water between cells, and the third stage is dried at low temperature to constant weight. f. Oxygen-proof encapsulation and packaging: Spray food-grade antioxidant film-forming solution onto the surface of dried stems and leaves to form a protective layer, and then air-dry and vacuum-packed with nitrogen.

2. The processing method as described in claim 1, characterized in that, The cleaning process described in step a includes rinsing with running water and then soaking in 0.5% saline solution for 1 minute; the cutting process involves cutting the stem into 3-5cm segments while keeping the leaves intact.

3. The processing method as described in claim 1, characterized in that, In step b: The high-temperature sterilization process uses steam or infrared heating to raise the temperature to 70°C and maintain it for 30 seconds, then cools it down to 50°C. The low-temperature aroma preservation and softening process involves treating the stems and leaves with 50°C hot air or swirling air for 12-15 minutes, during which the stems and leaves are continuously turned over, and the humidity of the hot air is controlled at 50-60%RH.

4. The processing method as described in claim 1, characterized in that, The conditions for the softening treatment in step c are: temperature 40℃, humidity 70%RH, and time 20 minutes; the medicinal property regulating excipients are 0.5% wolfberry powder and 0.5% ginger juice by weight of stems and leaves, which are mixed in by spraying.

5. The processing method as described in claim 1, characterized in that, In step d: the concentration of the cellulase solution is 0.1%, the spraying amount is 0.1% ± 0.02% of the stem and leaf weight, and the enzymatic hydrolysis time is 5 ± 1 minutes; the rolling treatment is carried out using a silicone-coated roller to achieve a stem and leaf cell wall breakage rate of 80%.

6. The processing method as described in claim 1, characterized in that, The programmed heating and drying process described in step e is specifically as follows: First stage: constant temperature treatment at 50℃ for 12 minutes; Second stage: constant temperature treatment at 55℃ for 25 minutes; Third stage: Dry at a constant temperature of 45℃ until the moisture content of the stems and leaves reaches 8±0.5%.

7. The processing method as described in claim 1, characterized in that, The food-grade antioxidant film-forming solution mentioned in step f is a 0.05% vitamin C solution or a 0.1% chitosan solution, and the thickness of the film formed does not exceed 50 micrometers; the packaging is vacuum nitrogen-filled dispensing using aluminum film light-shielding material.

8. The herbal tea or herbal slices prepared by the processing method according to any one of claims 1 to 7.

Images