Evaluation method for surface crusting degree of traditional Chinese medicine extract

Abstract

The invention discloses a method for evaluating the surface crusting degree of a traditional Chinese medicine extract. The method for evaluating the surface crusting degree of the traditional Chinese medicine extract provided by the invention comprises the following steps: determining the texture indexes of the surface crusting of the traditional Chinese medicine extract under different drying conditions by using a texture analyzer, and researching the reduced pressure drying characteristics of the rhizoma polygonati extract under different drying conditions by adopting a drying experiment; a texture analyzer detection result and a drying experiment evaluation result are combined for correlation analysis, and the surface crusting degree of the traditional Chinese medicine extract is comprehensively evaluated. According to the method provided by the invention, the detection result of the texture analyzer and the evaluation result of the drying experiment are combined for correlation analysis, the surface crusting degree of the traditional Chinese medicine extract is comprehensively evaluated, and compared with a traditional sensory evaluation method, the method is more convenient, objective and accurate, so that the subjective influence generated by sensory detection can be avoided as far as possible; and the process level of the traditional Chinese medicine extract reduced-pressure drying technology is improved, and the method has important significance for improving quality and efficiency of traditional Chinese medicine extract reduced-pressure drying.

Description

Technical Field

[0001] The invention belongs to the technical field of Chinese herbal medicines, and in particular relates to a method for evaluating the degree of crusting on the surface of a Chinese herbal medicine extract. Background Art

[0002] As an important intermediate for preparing modern solid preparations such as Chinese medicine granules, tablets, and capsules, Chinese medicine dry extracts directly affect the quality of medicines. Drying is an indispensable process for obtaining Chinese medicine dry extracts in preparation production. Since the traditional Chinese medicine extract drying method is mainly based on heat treatment, it has the disadvantages of long drying time, high drying temperature, poor quality of dried products, high energy consumption and low production efficiency. Therefore, continuously improving the drying technology of extracts is an important guarantee for the modernization of Chinese medicine pharmaceutical manufacturing. Vacuum drying is one of the main drying methods for Chinese medicine extracts. It has the advantages of being simple and easy to operate, low drying temperature, low oxygen content in the drying oven, and a wide range of applicability. However, vacuum drying has high labor intensity and low thermal efficiency (thermal energy utilization rate is less than 40%). During the drying process, the material is prone to surface crusting and pseudo-drying. Even after drying for several days, it still cannot meet the requirements of subsequent crushing for the moisture content of the dry extract, resulting in the inability to crush and interruption of the production process. A large number of production and research practices have shown that surface crusting is a common phenomenon in the vacuum drying process of Chinese medicine extracts. Since the shell layer seriously hinders the migration of internal moisture to the surface of the extract, it is difficult to dry the extract, resulting in a false surface drying with dry outside and wet inside. Therefore, surface crusting is an important reason and key common problem for the low efficiency of vacuum drying of Chinese medicine extracts.

[0003] However, there is almost no research on the surface crusting during the vacuum drying process of traditional Chinese medicine extracts, and in practice, there is still no solution to this problem.

[0004] In view of this, the present invention is proposed. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and provide a method for evaluating the degree of crusting on the surface of traditional Chinese medicine extract.

[0006] The present invention solves the technical problem by adopting the following technical solutions.

[0007] The embodiment of the present invention provides a method for evaluating the degree of crusting on the surface of a traditional Chinese medicine extract, comprising: using a texture analyzer to determine the textural indexes of crusting on the surface of the traditional Chinese medicine extract under different drying conditions, and simultaneously using a drying experiment to study the reduced-pressure drying characteristics of a polygonatum extract under different drying conditions, combining the texture analyzer detection results with the drying experiment evaluation results to perform a correlation analysis, and comprehensively evaluating the degree of crusting on the surface of the traditional Chinese medicine extract.

[0008] The present invention has the following beneficial effects:

[0009] The present invention provides a method for evaluating the degree of crusting on the surface of a Chinese medicine extract, comprising: using a texture analyzer to determine the textural index of crusting on the surface of a Chinese medicine extract under different drying conditions, and simultaneously using a drying experiment to study the reduced pressure drying characteristics of a polygonatum extract under different drying conditions, combining the texture analyzer test results with the drying experiment evaluation results to perform a correlation analysis, and comprehensively evaluating the degree of crusting on the surface of the Chinese medicine extract. The above method provided by the present invention combines texture analyzer detection with vacuum drying experiments, combines the texture analyzer test results with the drying experiment evaluation results to perform a correlation analysis, and comprehensively evaluates the degree of crusting on the surface of the Chinese medicine extract, which is more convenient, objective, and accurate than traditional sensory evaluation methods, thereby being able to avoid the subjective influence of sensory detection as much as possible, and having a good guiding significance for improving the drying efficiency and quality of Chinese medicine extracts by reduced pressure drying. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0011] Figure 1 The curves of the water ratio of Chinese medicine extracts changing with time at different temperatures;

[0012] Figure 2 The curves of the drying rate of Chinese medicine extracts changing with time at different temperatures;

[0013] Figure 3 The curves of the water ratio of Chinese medicine extracts changing with time under different vacuum degrees;

[0014] Figure 4 The curves of drying rate of Chinese medicine extract under different vacuum degrees are shown below;

[0015] Figure 5 The pressure was -0.08MPa, and the extract was dried at 70℃ for 6 hours. The texture analyzer test was used for the extract.

[0016] Figure 6 The texture analyzer test value of Chinese medicine extract is -0.08MPa, dried at 80℃ for 6 hours;

[0017] Figure 7 The texture analyzer test value of Chinese medicine extract is -0.08MPa, dried at 90℃ for 6 hours;

[0018] Figure 8 The texture analyzer test value of Chinese medicine extract after drying for 6 hours at 90℃ and -0.06MPa;

[0019] Fig. 9 The texture analyzer test value of Chinese medicine extract after drying for 6 hours at 90℃ and -0.07MPa;

[0020] Fig.10 The texture analyzer test value of Chinese medicine extract after drying for 6 hours at 90℃ and -0.08MPa;

[0021] Fig.11 The curve of the water ratio of Chinese medicine extract changing with time under the conditions of -0.08MPa and 70℃ (left figure) and the texture analyzer detection value of Chinese medicine extract (right figure). DETAILED DESCRIPTION

[0022] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0023] The following is a specific description of a method for evaluating the degree of crusting on the surface of a traditional Chinese medicine extract provided in an embodiment of the present invention.

[0024] The embodiment of the present invention provides a method for evaluating the degree of crusting on the surface of a traditional Chinese medicine extract, comprising: using a texture analyzer to determine the textural indexes of crusting on the surface of the traditional Chinese medicine extract under different drying conditions, and simultaneously using a drying experiment to study the reduced-pressure drying characteristics of a polygonatum extract under different drying conditions, combining the texture analyzer detection results with the drying experiment evaluation results to perform a correlation analysis, and comprehensively evaluating the degree of crusting on the surface of the traditional Chinese medicine extract.

[0025] The crusting on the surface of Chinese herbal medicine extracts is an important reason and key common problem for the low efficiency of vacuum drying of Chinese herbal medicine extracts. However, the causes of crusting are complex, and the formation time of the shell is very short, which is difficult to capture in seconds by naked eye observation, and the hardness of the initial shell is low. Due to the limitations of SEM sampling and the complexity of the causes of crusting of the extract itself, it is difficult to compare groups and make scientific and effective evaluations.

[0026] After research and practice, the inventor proposed a method for evaluating the degree of crusting on the surface of Chinese medicine extracts, which combines the test results of the texture analyzer and the evaluation results of the drying experiment to conduct a correlation analysis and comprehensively evaluate the degree of crusting on the surface of the Chinese medicine extracts. Although the complexity of the causes of crusting of the extracts themselves is difficult to compare in groups, the crusting mechanism of the extracts under different drying conditions is consistent. The texture analyzer (TA) experiment directly places the entire extract on the sample table for detection, so the position of the probe falling is controlled to be fixed, which is convenient for comparing the textural indicators of the materials under different drying conditions, and exploring the influence of drying conditions on surface crusting. At the same time, combined with the evaluation results of the drying experiment, the degree of crusting on the surface of the Chinese medicine extract can be evaluated more objectively, providing favorable support for improving the drying efficiency of the Chinese medicine extract.

[0027] In an optional embodiment, the method comprises the following steps: preparing a Chinese medicine extract and taking samples for later use; testing the texture indexes of the samples at different temperatures and vacuum degrees using a texture analyzer to obtain a basic database of the degree of crusting on the surface of the Chinese medicine extract samples; clustering analysis is performed on the hardness values ​​of the samples in the basic database to establish the crusting law of the Chinese medicine extract samples; at the same time, a drying experiment is performed to determine the weight of the samples at different temperatures and vacuum degrees, and a drying kinetic model of the relationship between the moisture ratio and the drying time is established; correlation analysis is performed on the texture analyzer test results of multiple groups of different samples and the drying experiment evaluation results, and the degree of crusting on the surface of the Chinese medicine extract is comprehensively evaluated.

[0028] In an optional embodiment, the measurement mode is a compression mode, and the probe is a P / 2 cylindrical probe.

[0029] In an optional embodiment, the parameters are set as follows: the probe puncture speed is 0.5 mm / s, the probe post-puncture speed is 10 mm / s, and the puncture distance ends when the puncture is 0.6 mm away from the bottom of the extract.

[0030] In an optional embodiment, the textural indicators include hardness, viscosity, compressive strength, elasticity and tensile strength.

[0031] In an optional embodiment, using a texture analyzer to determine the texture index of the crust on the surface of the Chinese medicine extract under different drying conditions includes: using a texture analyzer to determine the texture index of the crust on the surface of the Chinese medicine extract at different temperatures;

[0032] Preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at 50-100°C, and more preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at 70°C, 80°C, and 90°C.

[0033] In an optional embodiment, using a texture analyzer to measure the texture index of the crust on the surface of the Chinese medicine extract under different drying conditions includes: using a texture analyzer to respectively measure the texture index of the crust on the surface of the Chinese medicine extract under different vacuum degrees;

[0034] Preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at -0.06Mpa to -1.00Mpa, respectively. More preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at -0.06Mpa, -0.07Mpa, and -0.08Mpa, respectively.

[0035] In an optional embodiment, the drying experiment is used to study the reduced pressure drying characteristics of the polygonatum sibiricum extract under different drying conditions, including: placing the Chinese medicine extract in a vacuum drying oven, and establishing a curve of moisture ratio, drying rate and drying time by examining the weight of the sample at different temperatures and vacuum degrees, and determining the crusting behavior on the surface of the Chinese medicine extract;

[0036] Preferably, the drying experiment is used to study the reduced pressure drying characteristics of the polygonatum sibiricum extract under different drying conditions, including: placing the Chinese medicine extract in a vacuum drying oven, and establishing a curve of moisture ratio, drying rate and drying time by examining the weight of the sample at a temperature of 50-100°C and a vacuum degree of -0.06Mpa to -1.00Mpa, and determining the crusting behavior on the surface of the Chinese medicine extract;

[0037] More preferably, the Chinese medicine extract is placed in a vacuum drying oven, and the weight of the sample is examined at temperatures of 70°C, 80°C, and 90°C and at vacuum degrees of -0.06Mpa, -0.07Mpa, and -0.08Mpa, to establish a curve of moisture ratio, drying rate and drying time, and determine the crusting behavior on the surface of the Chinese medicine extract.

[0038] In an optional embodiment, the method of Chinese medicine extract is: prepare a standard Chinese medicine decoction according to the method of standard decoction of Chinese medicine pieces: take an appropriate amount of Polygonatum sibiricum decoction pieces, add 8 times the amount of water to soak for 30 minutes, decoct 3 times, each time for two hours, pass through 200 mesh gauze while hot, combine the decoction, let it stand overnight to precipitate, take the supernatant and concentrate it at a temperature of 75°C to a relative density of 1.25g / cm at 25°C 3 The thick paste concentrate is refrigerated in the freezer.

[0039] The present invention will be further described below in conjunction with the embodiments.

[0040] A method for evaluating the degree of crusting on the surface of a traditional Chinese medicine extract comprises the following steps (hereinafter described using polygonatum extract as an example):

[0041] Preparation of Polygonatum sibiricum extract:

[0042] Prepare the standard decoction of Polygonatum odoratum according to the preparation method of standard decoction of Chinese herbal medicine. Take an appropriate amount of Polygonatum odoratum decoction slices, add 8 times the amount of water to soak for 30 minutes, decoct for 3 times, each time for 2 hours, pass through 200 mesh gauze while hot, combine the decoction, leave it overnight to precipitate, take the supernatant and concentrate it at 75℃ to a relative density of 1.25g / cm 3 . The thick paste concentrate (measured at 25°C) is placed in a freezer for refrigeration.

[0043] Drying of Polygonatum sibiricum extract:

[0044] In order to explore the vacuum drying characteristics of Polygonatum sibiricum extract, 80g of Polygonatum sibiricum extract was accurately weighed, spread on a metal tray with a width of 15cm and a length of 20cm, and placed in a vacuum drying oven for drying. The relevant parameters were taken out every 60 minutes to measure, and the measurement of various parameters was completed quickly. To ensure the continuity of the drying parameters, the extract with the same initial parameters was weighed again each time the drying was carried out until the drying lasted for twelve hours. By investigating the influence of vacuum degree (-0.06Mpa, -0.07Mpa, -0.08Mpa) and drying temperature (70℃, 80℃, 90℃) on the dry basis moisture content and water loss rate of the extract, the curve of moisture ratio, drying rate and drying time was established. The dried product obtained in each experiment was measured in parallel 3 times.

[0045] Moisture ratio

[0046] The moisture ratio indicates the ratio of the sample's moisture content at time t to the initial moisture content under certain drying conditions, and can be used to reflect the drying rate of the material. Calculate using the following formula.

[0047] MR=(MM 平衡 ) / (M pre -M 平衡 )

[0048] Where: M is the moisture content of the sampling point; M pre and M 平衡 The initial moisture content and the dry basis moisture content at drying equilibrium. The dry basis moisture content M of the material at drying equilibrium 平衡 Much smaller than the initial dry basis moisture content M pre ,because

[0049] This can be approximately considered as M 平衡 The value of is zero.

[0050] Water loss rate

[0051] The water loss rate during the drying process is expressed by the change in the dry basis moisture content of the material at adjacent time points within a certain period of time, and is calculated using the following formula.

[0052] DR=(M t1 -M t1+Δt ) / Δt

[0053] Where: DR is the water loss rate (g / (g·min)); M t1 、M t1+Δt They represent the dry basis moisture content (g / g) of the material at time t1 and t1+Δt respectively; Δt is the time difference (min).

[0054] Figure 1-2 , Figure 3-4 These are the drying characteristic curves of Chinese medicine extract at different temperatures and vacuum degrees. The experiment shows that drying temperature and vacuum degree are important factors affecting the reduced pressure drying of Polygonatum sibiricum extract. When the drying temperature is constant, the higher the vacuum degree, the faster the moisture ratio decreases and the more significant the increase in drying rate, and vice versa.

[0055] Texture Analyzer Parameter Settings

[0056] The surface shell of Polygonatum sibiricum extract is hard in the later stage of drying. The preliminary experiment found that the use of P / 2N needle probe will cause the needle to deform, affecting the sensitivity and accuracy of the test results, so P / 2 column probe was selected. After a long period of debugging and optimization, the test mode was selected as compression, the probe puncture speed was 0.5mm / s, the probe post-puncture speed was 10mm / s, and the puncture distance was ended when the puncture was 0.6mm away from the bottom of the extract, so as to reflect the mechanical information of the extract from the surface to the bottom to the greatest extent.

[0057] Depend on Figure 1-4 It can be seen that within the first 6 hours of drying, the strength of the force on the surface of the Polygonatum sibiricum extract is not much different. After 6 hours, the hardness of the surface shell of the extract is proportional to the drying time. The longer the drying time, the greater the hardness. The reason is related to the migration of internal moisture when heated, the physical and chemical properties of the extract itself, and external environmental factors. When the extract is heated, complex physical and chemical reactions occur, and the moisture and heat transfer process is very complex, resulting in a porous structure of the surface shell that is quite complex.

[0058] According to the drying experiment, it is found that the drying temperature is the key factor affecting the drying rate. The drying temperature is inversely proportional to the drying time and directly proportional to the drying rate. The higher the drying rate of the extract means the faster the water loss rate. During the drying process of the Polygonatum sibiricum extract, the surface shell solidifies from the outside to the inside, and the hardness increases accordingly. Figure 5-7 , controlling the vacuum degree unchanged, and using the probe to sample the sample at the same location within the same drying time, it can be found that the temperature increase is proportional to the hardness of the surface shell. The result is consistent with the conclusion of the drying experiment. At -0.08MPa, when dried for 6h, the surface hardness under the controlled temperature of 90℃ is 26.67 and 10.67 times that of 70℃ and 80℃ respectively.

[0059] See also Figure 8-10During the same drying time, the drying temperature is kept unchanged. The degree of crusting on the surface of the extract is different under different vacuum degrees. As the vacuum degree increases, the sample is sampled at the same location within the same drying time using a probe. It can be found that the results are similar to those presented by the drying temperature. When the vacuum degree increases, the hardness of the surface shell will also increase. At 90°C, when dried for 6 hours, the surface hardness controlled at a temperature of -0.08MPa is 16 and 13.33 times that of -0.06MPa and -0.07MPa, respectively.

[0060] By comparing the two sets of data, it can be found that the higher the drying temperature and vacuum degree, the harder the shell layer on the surface of the extract is, which indirectly reflects the greater degree of crusting on the surface of the extract. Due to the complex mass transfer and heat transfer mechanism of the extract during heating, there are many factors that affect it, such as the heat transfer mode between the gaseous water in the pores and the solid skeleton, the heat radiation effect of the inner wall of the drying box on the material, and the physical and chemical properties of the extract itself. The above experimental results alone cannot be used to fully determine the cause of crusting. The increase of drying temperature and vacuum degree can aggravate the degree of surface crusting to a certain extent, but the disadvantages may be ignored when the temperature is increased to a certain range. Combined with the drying experiment, it can be seen that under the three groups of conditions, the drying rate at 90℃ is the highest, significantly greater than 70℃ and 80℃, but the drying rate does not increase proportionally with the increase of temperature. On the contrary, the difference in drying characteristics between 70℃ and 80℃ is smaller than that between 90℃ and 70℃, and between 90℃ and 80℃. The initial consideration is that the shell layer formed on the surface of the extract affects the migration speed of water. When the drying temperature and vacuum degree exceed a certain limit, the surface crust can then weaken the barrier to water loss.

[0061] See also Fig.11 Taking the Polygonatum sibiricum extract dried under -0.08MPa and 70℃ as an example, combined with its moisture ratio curve (left figure) and texture analyzer test value (right figure), it can be observed that the force value (surface hardness) detected by the TA probe was 1300g at 12h. It can be found that the hardness of the shell is inversely proportional to the moisture ratio of the system. At the same time, observing the surface image collected by SEM, it can be seen that pores have appeared on the surface of the shell at this time, thereby indirectly judging the degree of crusting of the extract, and conversely using the change in moisture ratio to control the drying time of the extract to regulate the crusting behavior.

[0062] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for evaluating the degree of crusting on the surface of a traditional Chinese medicine extract, characterized in that: include: A texture analyzer was used to determine the textural indicators of crusting on the surface of Chinese herbal extracts under different drying conditions. At the same time, a drying experiment was used to study the reduced-pressure drying characteristics of Polygonatum sibiricum extracts under different drying conditions. The texture analyzer test results and the drying experiment evaluation results were combined for correlation analysis to comprehensively evaluate the degree of crusting on the surface of Chinese herbal extracts.

2. The method according to claim 1, characterized in that The following steps are involved: The texture indexes of the samples at different temperatures and vacuum degrees are tested by a texture analyzer to obtain a basic database, and the texture indexes in the basic database are clustered by a cluster analysis method to reflect the degree of crusting on the surface of the Chinese medicine extract; at the same time, the weight of the samples at different temperatures and vacuum degrees is measured by a drying experiment, and a curve of moisture ratio, drying rate and drying time is established to determine the crusting behavior on the surface of the Chinese medicine extract; The correlation analysis was performed on the texture analyzer test results and drying experiment evaluation results of multiple groups of different samples, and the degree of crusting on the surface of Chinese medicine extracts was comprehensively evaluated.

3. The method according to claim 1, characterized in that The texture analyzer measurement mode is compression mode.

4. The method according to claim 3, characterized in that The texture analyzer probe is a P / 2 column probe.

5. The method according to claim 3, characterized in that: The parameters were set as follows: probe puncture speed of 0.5 mm / s, probe post-puncture speed of 10 mm / s, and puncture distance ended when the puncture reached a distance of 0.6 mm from the bottom of the extract.

6. The method according to claim 1, characterized in that The texture indicators include hardness, viscosity, compressive strength, elasticity and tensile strength.

7. The method according to claim 1, characterized in that The texture indexes of the surface crust of the Chinese medicine extract under different drying conditions are measured by using a texture analyzer, including: using a texture analyzer to measure the texture indexes of the surface crust of the Chinese medicine extract under different temperatures; Preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at 50-100°C, and more preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at 70°C, 80°C, and 90°C.

8. The method according to claim 1, characterized in that Using a texture analyzer to measure the texture indexes of the crust on the surface of the Chinese medicine extract under different drying conditions includes: using a texture analyzer to measure the texture indexes of the crust on the surface of the Chinese medicine extract under different vacuum degrees; Preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at -0.06Mpa to -1.00Mpa, respectively. More preferably, a texture analyzer is used to measure the texture indices of the crust on the surface of the traditional Chinese medicine extract at -0.06Mpa, -0.07Mpa, and -0.08Mpa, respectively.

9. The method according to claim 1, characterized in that: The drying experiment was used to study the reduced pressure drying characteristics of polygonatum sibiricum extract under different drying conditions, including: placing the Chinese medicine extract in a vacuum drying oven, and establishing a curve of water ratio, drying rate and drying time by examining the weight of the sample at different temperatures and vacuum degrees, and determining the crusting behavior on the surface of the Chinese medicine extract; Preferably, the drying experiment is used to study the reduced pressure drying characteristics of the polygonatum sibiricum extract under different drying conditions, including: placing the Chinese medicine extract in a vacuum drying oven, and establishing a curve of moisture ratio, drying rate and drying time by examining the weight of the sample at a temperature of 50-100°C and a vacuum degree of -0.06Mpa to -1.00Mpa, and determining the crusting behavior on the surface of the Chinese medicine extract; More preferably, the Chinese medicine extract is placed in a vacuum drying oven, and the weight of the sample is examined at temperatures of 70°C, 80°C, and 90°C and at vacuum degrees of -0.06Mpa, -0.07Mpa, and -0.08Mpa, to establish a curve of moisture ratio, drying rate and drying time, and determine the crusting behavior on the surface of the Chinese medicine extract.

10. The method according to claim 1, characterized in that The method of the Chinese medicine extract is as follows: prepare the Chinese medicine standard decoction according to the method of the Chinese medicine decoction piece standard decoction: take an appropriate amount of Chinese medicine decoction piece, add 8 times the amount of water to soak for 30 minutes, decoct for 3 times, each time for 2 hours, pass through 200 mesh gauze while hot, combine the decoction, place overnight to precipitate, take the supernatant and concentrate it at a temperature of 75°C to a relative density of 1.25g / cm at 25°C. 3 The thick paste concentrate is refrigerated in the freezer.

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