Radix puerariae black tea beverage and preparation method thereof

Abstract

The present application relates to a kind of gualou red tea and its preparation method, the preparation method includes the following steps: gualou powder is mixed with black tea powder, the mixed powder of gualou powder is coated by the black tea powder is obtained;90-100 ℃ pure water is added in the mixed powder, after stirring and standing extraction, the gualou red tea is obtained, wherein, the mass ratio of the mixed powder and the pure water is 1:15-25, the gelatinization degree of the mixed powder is 80%-98%.The preparation method provided by the present application significantly improves the instant solubility and dispersion stability of the product, and the obtained high-concentration gualou red tea system is uniform, without caking and delamination;At the same time, the earthy smell of gualou and the mellow aroma of black tea are ingeniously blended, so that the final beverage is mild in nature and taste, smooth in mouthfeel and non-harmful to the spleen and stomach. The gualou red tea prepared by the preparation method of the present application maximizes the retention of active ingredients and stimulates its biological activity of regulating sugar and lipid metabolism and anti-inflammatory.

Description

Technical Field

[0001] This invention relates to the field of food industry technology, and in particular to kudzu root black tea and its preparation method. Background Technology

[0002] With dietary patterns shifting towards high-fat, high-calorie diets, the prevalence of metabolic syndromes such as obesity, hyperglycemia, hyper-LDL cholesterol, and fatty liver is increasing year by year, and the affected population is becoming increasingly younger. Current pathological studies indicate that a long-term high-fat diet disrupts the body's glucose and lipid metabolism homeostasis, damages the intestinal mucosal barrier, induces leaky gut syndrome, promotes the entry of intestinal endotoxins into the bloodstream and their accumulation in the liver, activates the body's immune cells, and releases large amounts of pro-inflammatory factors such as interleukin-1β, interleukin-6, and tumor necrosis factor-α, inducing chronic low-grade inflammation throughout the body and in the liver. This pathological reaction is a core contributing factor to insulin resistance, impaired glucose tolerance, and endogenous lipid metabolism disorders. Therefore, developing a functional food that can block endotoxin translocation at its source, inhibit systemic inflammation, and restore glucose and lipid metabolism homeostasis has become an urgent need in the field of health and wellness.

[0003] Kudzu root is rich in isoflavones such as puerarin and daidzein, which have the potential to regulate the body's "three highs" (high blood pressure, high blood sugar, and high cholesterol); black tea contains abundant tea polyphenols and theaflavins, possessing excellent antioxidant properties. Theoretically, the combination of the two can produce a synergistic effect. However, the current technology for preparing high-concentration functional beverages by combining kudzu root and black tea faces two technical bottlenecks:

[0004] Firstly, it is difficult to balance physical processing with sensory quality. Kudzu root powder, rich in starch, has extremely high viscosity, making it prone to clumping, absorbing water and swelling, and causing severe stratification or sedimentation when prepared at high concentrations, resulting in a sticky taste and an earthy flavor. Conversely, if black tea powder is mixed with kudzu root powder using conventional methods, its volatile aroma compounds easily antagonize the flavor of the kudzu root components, leading to a mixed aroma and poor palatability. Especially in ultra-concentrated states with a material-to-water ratio of 1:15 to 1:25, overcoming the dispersion challenge at high viscosity to achieve instant solubility, a smooth taste, and long-term system stability remains a technical hurdle in the industry.

[0005] Secondly, the synergistic effect of the drugs is insufficient. Most of the existing commercially available products are simple physical mixed tea bags or low-concentration liquid beverages. Not only is the dissolution rate of kudzu isoflavones and tea polyphenols low, but no research has been carried out on the compatibility optimization of the ingredients. The active ingredients of the raw materials are prone to antagonistic effects in vivo, and cannot achieve the synergistic effect of intercepting endotoxins, systemic anti-inflammation, and regulating glucose and lipid metabolism.

[0006] In summary, developing suitable formulations and processing techniques for preparing high-concentration kudzu black tea beverages, and solving the problems of flavor blending, system stability, and synergistic efficacy, are urgent technical issues to be addressed in this field. Summary of the Invention

[0007] Based on this, it is necessary to provide a kudzu root black tea beverage and its preparation method to address the above problems. This preparation method significantly improves the product's solubility and dispersion stability, resulting in a high-concentration kudzu root black tea beverage system that is uniform, free of lumps and stratification, maximizing the retention of active ingredients and stimulating their biological activities in regulating glucose and lipid metabolism and anti-inflammation. At the same time, it harmonizes the earthy smell of kudzu root with the mellow aroma of black tea, making the final beverage mild in nature and smooth in taste.

[0008] A method for preparing kudzu root black tea includes the following steps:

[0009] Kudzu root powder and black tea powder are mixed to obtain a mixed powder in which the black tea powder coats the kudzu root powder.

[0010] Pure water at 90-100℃ is added to the mixed powder, and after stirring and standing extraction, the kudzu root black tea is obtained. The mass ratio of the mixed powder to the pure water is 1:15-25, and the gelatinization degree of the mixed powder is 80%-98%.

[0011] In one embodiment, the kudzu root powder and the black tea powder are placed in a dry powder mixer and stirred for 2-10 minutes to obtain the mixed powder.

[0012] In one embodiment, the mixing speed of the dry powder mixer is 100-500 rpm.

[0013] In one embodiment, the kudzu root powder and the black tea powder constitute 45-55% by mass in the mixed powder.

[0014] In one embodiment, the kudzu root powder is selected from Bupleurum chinense root powder.

[0015] In one embodiment, the black tea powder is selected from Qimen black tea powder.

[0016] In one embodiment, the kudzu root powder has a particle size of 100-300 mesh, and the black tea powder has a particle size of 100-300 mesh; wherein the particle size ratio of the kudzu root powder to the black tea powder is 1:1-2.

[0017] In one embodiment, the stirring time is 1-2 minutes.

[0018] In one embodiment, the extraction time is 3-10 minutes.

[0019] A kudzu root black tea beverage prepared by the above preparation method.

[0020] The method for preparing kudzu root black tea provided by this invention effectively solves the inherent problems of high viscosity, easy water absorption and swelling, and clumping and stratification of kudzu root powder. The resulting high-concentration kudzu root black tea system is uniform, without clumping or stratification, significantly improving the product's solubility and dispersion stability. At the same time, it cleverly harmonizes the earthy smell of kudzu root with the mellow aroma of black tea, making the final beverage mild in nature and taste, smooth in texture, and gentle on the spleen and stomach.

[0021] Most importantly, the deep physical integration stimulates the synergistic pharmacodynamics between chemical components, allowing the kudzu root black tea prepared by the method of this invention to maximize the retention of active ingredients and enhance its biological activities in regulating glucose and lipid metabolism and anti-inflammation. This kudzu root black tea not only significantly reduces the area under the blood glucose curve induced by a high-fat diet, improves the fasting blood glucose baseline, and has a precise peak-shaving effect on postprandial blood glucose fluctuations, but also achieves bidirectional regulation of lipid metabolism, causing a sharp drop in low-density lipoprotein cholesterol while significantly restoring high-density lipoprotein cholesterol. Furthermore, this kudzu root black tea can significantly intercept the translocation of intestinal endotoxins into the blood and liver by improving intestinal barrier function, and completely block the systemic spread of pro-inflammatory factors such as interleukin-1β, interleukin-6, and tumor necrosis factor-α. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 The graph shows the content of kaempferol-3-O-rutin in the kudzu root black tea drinks prepared in Example 1 and Comparative Examples 1-6.

[0024] Figure 2 The graph shows the content of epicatechin in the kudzu root black tea beverages prepared in Example 1 and Comparative Examples 1-6.

[0025] Figure 3 The theaflavins content in the kudzu root black tea beverages prepared in Example 1 and Comparative Examples 1-6 is shown in the figure.

[0026] Figure 4 The graph shows the content of daidzein-4',7-diglucoside in the kudzu root black tea prepared in Example 1 and Comparative Examples 1-6.

[0027] Figure 5The graph shows the content of 4',6,7-trihydroxyisoflavone-6-methyl ether-7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside in the kudzu root black tea prepared in Example 1 and Comparative Examples 1-6.

[0028] Figure 6 The graph shows the content of 4',5,7-trihydroxy-6-methoxyisoflavone-7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside in the kudzu root black tea prepared in Example 1 and Comparative Examples 1-6.

[0029] Figure 7 The graph shows the content of malonyl daidzein in the kudzu root black tea drinks prepared in Example 1 and Comparative Examples 1-6.

[0030] Figure 8 The graph shows the content of puerarin xylososide II in the kudzu root black tea beverages prepared in Example 1 and Comparative Examples 1-6.

[0031] Figure 9 The graph shows the content of puerarin C in the kudzu root black tea beverages prepared in Example 1 and Comparative Examples 1-6.

[0032] Figure 10 The graph shows the rutin content in the kudzu root black tea drinks prepared in Example 1 and Comparative Examples 1-6.

[0033] Figure 11 The graph shows the content of new North American sagein in the kudzu root black tea drinks prepared in Example 1 and Comparative Examples 1-6;

[0034] Figure 12 The graph shows the content of isochlorogenic acid B in the kudzu root black tea drinks prepared in Example 1 and Comparative Examples 1-6.

[0035] Figure 13 The area under the blood glucose curve for each group of mice is plotted.

[0036] Figure 14 The graph shows the dynamic fluctuation of blood glucose in each group of mice over 120 minutes.

[0037] Figure 15 A graph showing the levels of low-density lipoprotein cholesterol in the serum of mice in each group;

[0038] Figure 16 A graph showing the levels of high-density lipoprotein cholesterol in the serum of mice in each group;

[0039] Figure 17 The graph shows the concentrations of local pro-inflammatory cytokines and endotoxins in the liver tissue of mice in each group. In the graph, A represents the concentration of interleukin-1β, B represents the concentration of interleukin-6, and C represents the concentration of endotoxin.

[0040] Figure 18 The graph shows the concentrations of systemic pro-inflammatory cytokines and endotoxins in the serum of mice in each group. In the graph, A represents the concentration of interleukin-1β, B represents the concentration of interleukin-6, C represents the concentration of tumor necrosis factor-α, and D represents the concentration of endotoxins.

[0041] Figure 19 HE staining images of liver tissue from mice in each group are shown below. A is an HE staining image of liver tissue from the normal group (magnification 2.0×, scale bar 500μm), B is an HE staining image of liver tissue from the normal group (magnification 20.0×, scale bar 50μm), C is an HE staining image of liver tissue from the normal group with added tea (magnification 2.0×, scale bar 500μm), and D is an HE staining image of liver tissue from the normal group with added tea (magnification 20.0×, scale bar 500μm). E is an HE staining image of liver tissue from mice in the high-fat group (magnification 2.0×, scale bar 500μm), F is an HE staining image of liver tissue from mice in the high-fat group (magnification 20.0×, scale bar 50μm), G is an HE staining image of liver tissue from mice in the high-fat plus tea group (magnification 2.0×, scale bar 500μm), and H is an HE staining image of liver tissue from mice in the high-fat plus tea group (magnification 20.0×, scale bar 50μm). Detailed Implementation

[0042] To facilitate understanding of the present invention, it will be described in more detail below. However, it should be understood that the present invention can be implemented in many different forms and is not limited to the embodiments or examples described herein. Rather, these embodiments or examples are provided to make the disclosure of the present invention more thorough and complete.

[0043] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the specification of this invention is for the purpose of describing particular embodiments or examples only and is not intended to limit the invention. The optional scope of the term "and / or" as used herein includes any one of two or more of the related listed items, as well as any and all combinations of the related listed items, including any two related listed items, any more related listed items, or a combination of all related listed items.

[0044] In this invention, numerical ranges are involved. Unless otherwise specified, the numerical ranges are considered continuous and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to an integer, it includes the range's description, every integer between the minimum and maximum values. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are included.

[0045] A method for preparing kudzu root black tea includes the following steps:

[0046] Kudzu root powder and black tea powder are mixed to obtain a mixed powder in which the black tea powder coats the kudzu root powder.

[0047] Pure water at 90-100℃ is added to the mixed powder, and after stirring and standing extraction, the kudzu root black tea is obtained. The mass ratio of the mixed powder to the pure water is 1:15-25, and the gelatinization degree of the mixed powder is 80%-98%.

[0048] Understandably, in highly concentrated scenarios with a material-to-water ratio of 1:15-25, the high viscosity resulting from the instantaneous gelatinization of kudzu root powder upon contact with water is the root cause of particle agglomeration and clumping. To address this, this invention utilizes a mixture of kudzu root powder and black tea powder, uniformly coating the kudzu root powder surface to form a physical "isolation layer." This structure effectively prevents direct contact and adhesion between kudzu root powder particles during the initial hydration stage, mitigating the risk of clumping from the outset. Simultaneously, the mixed powder exhibits a uniform light reddish-brown color, providing a direct visual basis for assessing the mixing uniformity during the process.

[0049] Based on this, the preparation method of the present invention further adds 90-100℃ pure water to the mixed powder, and uses stirring to promote dissolution and static extraction processes. This not only enables controllable in-situ gelatinization of kudzu root, controlling the gelatinization degree of the mixed powder to 80%-98%, but also accelerates the simultaneous dissolution of two functional components, kudzu root isoflavones and black tea polyphenols, maximizing the preservation of the structural integrity of the active components and stimulating their synergistic effect in vivo, ultimately producing a high-concentration kudzu root black tea beverage with a uniform system, no lumps, and no layering.

[0050] The method for preparing kudzu root black tea provided by this invention effectively solves the inherent problems of high viscosity, easy water absorption and swelling, and clumping and stratification of kudzu root powder, significantly improving the product's solubility and dispersion stability. The resulting high-concentration kudzu root black tea system is uniform, without clumping or stratification. Simultaneously, it cleverly harmonizes the earthy aroma of kudzu root with the mellow fragrance of black tea, resulting in a final beverage that is mild in nature and flavor, smooth in taste, and gentle on the spleen and stomach. Most importantly, the deep physical fusion stimulates the "synergistic effect" between chemical components, allowing the kudzu root black tea prepared by this method to maximize the retention of active ingredients and stimulate their biological activities in regulating glucose and lipid metabolism and anti-inflammation. This kudzu root black tea not only significantly reduces the area under the blood glucose curve induced by a high-fat diet and improves the fasting blood glucose baseline, but also has a precise peak-shaving effect on postprandial blood glucose fluctuations. Furthermore, it achieves bidirectional regulation of lipid metabolism, causing a sharp drop in low-density lipoprotein cholesterol while significantly restoring high-density lipoprotein cholesterol. In addition, this kudzu root black tea can significantly intercept the translocation of enterogenic endotoxins to the blood and liver by improving intestinal barrier function, and completely block the systemic spread of pro-inflammatory factors such as interleukin-1β, interleukin-6 and tumor necrosis factor-α.

[0051] To obtain a mixed powder in which the black tea powder coats the kudzu root powder, in some embodiments, the preparation method includes placing the kudzu root powder and the black tea powder in a dry powder mixer and stirring for 2-10 minutes to obtain the mixed powder. This invention utilizes a dry powder mixer to stir and mix the kudzu root powder and black tea powder for 2-10 minutes. Under the action of mechanical shearing force, the black tea powder uniformly coats the surface of the kudzu root powder, forming a physical "isolation layer."

[0052] To further achieve uniform mixing of the powders, the stirring speed of the dry powder mixer may optionally be 100-500 rpm.

[0053] In order to address the issues of clumping, swelling, and stratification of kudzu root powder under high-concentration formulation, and to balance the flavor, dissolution behavior of active ingredients, and in vivo efficacy of kudzu root powder and black tea powder, optionally, the mass percentage of kudzu root powder in the mixed powder is 45-55%, and the mass percentage of black tea powder is 45-55%; preferably, the mass percentage of kudzu root powder is 50%, and the mass percentage of black tea powder is 50%.

[0054] It is understandable that the content of puerarin and daidzein isoflavones in *Pueraria lobata* is significantly higher than in other kudzu roots, which is the material basis for its activity in regulating glucose and lipid metabolism. Qimen black tea is rich in unique theaflavins and aromatic substances; when combined with *Pueraria lobata*, it can more effectively mask the earthy taste of kudzu and exhibit stronger anti-inflammatory activity in vivo. In some embodiments, the kudzu root powder is selected from *Pueraria lobata* powder, and the black tea powder is selected from Qimen black tea powder.

[0055] In some embodiments, the kudzu root powder has a particle size of 100-300 mesh, and the black tea powder has a particle size of 100-300 mesh. This particle size range ensures that the kudzu root powder or black tea powder has a sufficiently large specific surface area to promote rapid dissolution during hot water extraction, while avoiding uneven mixing or clumping during brewing caused by excessively fine kudzu root powder or black tea powder due to severe electrostatic adsorption.

[0056] To ensure that the particle size of the black tea powder is always less than or equal to that of the kudzu root powder, preferably, the particle size ratio of the kudzu root powder to the black tea powder is 1:1-2. This ensures that the black tea powder and kudzu root powder can form a stable and uniform interlaced coating and spatial isolation when mixed, completely avoiding the technical defect of being unable to coat due to the extreme inversion of the particle sizes of the two components.

[0057] The increased surface area of ​​pulverized kudzu root powder and black tea powder makes them more susceptible to the adhesion of mold and other microorganisms. To sterilize, in some embodiments, the pulverized kudzu root powder and black tea powder are fed into a sterilization device for ultraviolet (UV) irradiation sterilization. The UV wavelength is controlled at 200-280 nm, preferably 254 nm, the irradiation dose is 30-100 mJ / cm², and the sterilization time is 10-30 min. After sterilization, a quantitative amount is temporarily stored. It is understood that sterilization after pulverization can directly inactivate microorganisms on the powder surface, reducing the risk of contamination in subsequent extraction and blending processes, and lessening the sterilization load at the end. Using 200-280 nm UV irradiation for sterilization avoids heat damage, fully preserving the heat-sensitive functional activities of kudzu root isoflavones and black tea polyphenols, and preventing the degradation of anti-inflammatory and lipid-regulating active ingredients by high-temperature sterilization. Furthermore, pre-sterilization of miscellaneous bacteria can prevent oxidation and mold growth and flavor deterioration during powder storage, ensuring uniform quality of the dry powder raw materials, stabilizing the active dissolution rate and efficacy of batch products, and improving batch consistency and food safety.

[0058] In some embodiments, the stirring time is 1-2 minutes. This invention adds purified water at 90-100℃ to the mixed powder and continuously stirs for 1-2 minutes. This utilizes high temperature to rapidly break down the crystalline regions of the starch granules, inducing controlled in-situ gelatinization of the kudzu root powder, rather than disordered water absorption and swelling. After stirring, the mixture is allowed to stand for 3-10 minutes for extraction, ensuring the full release of flavor compounds in the black tea while preventing the decomposition of heat-sensitive active substances caused by prolonged high temperatures. This process effectively ensures the long-term stability of the final product system without layering and a smooth taste.

[0059] After stirring and static extraction, the process further includes sterilization to obtain the kudzu root black tea beverage. The sterilization employs high-temperature instantaneous sterilization, controlling the sterilization temperature at 115-135℃ and the sterilization time at 4-15 seconds. This sterilization process after extraction kills impurities carried by the powder and microorganisms that grow during the extraction process, improving the beverage's stability at room temperature and preventing mold growth and flavor deterioration in high-concentration kudzu root black tea. This adapts the beverage to the needs of large-scale production, canning, storage, and long-term consumption of functional beverages, enhancing its industrial applicability.

[0060] A kudzu root black tea beverage prepared by the above preparation method.

[0061] The high-concentration kudzu root black tea beverage prepared by the method of this invention is homogeneous, without lumps or stratification, has a harmonious aroma, a mild and gentle taste, and is easy on the spleen and stomach, making it palatable. Animal efficacy tests have demonstrated that this kudzu root black tea beverage not only significantly reduces the area under the blood glucose curve induced by a high-fat diet and improves the fasting blood glucose baseline, but also has a precise peak-shaving effect on postprandial blood glucose fluctuations. Furthermore, it exhibits a strong lipid homeostasis repair ability, causing a sharp drop in low-density lipoprotein cholesterol and a significant rebound in high-density lipoprotein cholesterol, achieving bidirectional regulation. It also significantly intercepts the translocation of intestinal endotoxins to the blood and liver by improving intestinal barrier function, and completely blocks the systemic spread of pro-inflammatory factors such as interleukin-1β, interleukin-6, and tumor necrosis factor-α.

[0062] The technical solution of the present invention will be further described below through specific embodiments. However, those skilled in the art will understand that the following embodiments are only for illustrating the present invention and should not be regarded as limiting the scope of the present invention. Unless otherwise specified, specific conditions in the embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments used without specified manufacturers are all commercially available conventional products.

[0063] Example 1

[0064] The raw materials of Pueraria lobata powder and Qimen black tea powder were mechanically ground and pulverized separately, and then screened through a 200-mesh standard sieve to remove impurities, so as to obtain Pueraria lobata powder and Qimen black tea powder with uniform particle size distribution and a mesh size of 200 mesh.

[0065] The pulverized kudzu root powder and Qimen black tea powder were fed into a sterilization device for ultraviolet irradiation sterilization. The ultraviolet wavelength was controlled at 254nm, the irradiation dose was 100mJ / cm², and the sterilization time was 10min. After sterilization, the product was temporarily stored in a quantitative quantity.

[0066] Using an electronic balance, precisely weigh 0.5g of kudzu root powder and 0.5g of Qimen black tea powder respectively. Place the weighed kudzu root powder and Qimen black tea powder into a dry powder mixer equipped with a stirring paddle for thorough mixing. Start the dry powder mixer and control the stirring speed at 250 rpm, continuously stirring and mixing for 5 minutes. During this process, when the mixed powder reaches a completely uniform light reddish-brown color, and no visible local agglomeration of kudzu root powder or black tea powder is observed in randomly selected samples, it is considered fully mixed, and the mixed powder is obtained.

[0067] 20 mL of purified water at a temperature of 95℃-100℃ was injected into the mixed powder and placed in a brewing container that served as a normal pressure solid-liquid mixing reactor. The mixture was stirred continuously for 2 min to promote in-situ gelatinization of the kudzu root powder and accelerate the dissolution of the polyphenols in the black tea. The degree of gelatinization was 95.8%. The mixture was then allowed to stand for 5 min to extract the product, resulting in a kudzu root black tea beverage sample that was stable in long-term properties, free of lumps, and did not separate into layers.

[0068] The kudzu root black tea sample was sent to a sterilization device for high-temperature instantaneous sterilization. The sterilization temperature was controlled at 115℃ and the sterilization time was 15s to obtain the kudzu root black tea.

[0069] The kudzu root black tea beverage system obtained in Example 1 is uniform, without lumps or layers; at the same time, it cleverly harmonizes the earthy smell of kudzu root with the mellow aroma of black tea, making the final beverage mild in nature and taste, smooth in texture, and gentle on the spleen and stomach.

[0070] Comparative Example 1

[0071] The only difference between Comparative Example 1 and Example 1 is that in the raw materials of the kudzu root black tea drink in Comparative Example 1, the mass of kudzu root powder is 0.67g and the mass of Qimen black tea powder is 0.33g.

[0072] The degree of gelatinization was tested and found to be 42.3%.

[0073] Comparative Example 2

[0074] The only difference between Comparative Example 2 and Example 1 is that in the raw materials of the kudzu root black tea drink in Comparative Example 1, the mass of kudzu root powder is 0.75g and the mass of Qimen black tea powder is 0.25g.

[0075] The degree of gelatinization was tested and found to be 61.5%.

[0076] Comparative Example 3

[0077] The only difference between Comparative Example 3 and Example 1 is that in the raw materials of the kudzu root black tea drink in Comparative Example 1, the mass of kudzu root powder is 0.80g and the mass of Qimen black tea powder is 0.20g.

[0078] The degree of gelatinization was tested and found to be 53.8%.

[0079] Comparative Example 4

[0080] The only difference between Comparative Example 4 and Example 1 is that in the raw materials of the kudzu root black tea drink in Comparative Example 1, the mass of kudzu root powder is 0.90g and the mass of Qimen black tea powder is 0.10g.

[0081] The degree of gelatinization was tested and found to be 35.2%.

[0082] Comparative Example 5

[0083] The only difference between Comparative Example 5 and Example 1 is that the mass of kudzu root powder in the raw materials of the kudzu root black tea in Comparative Example 1 is 1.0g.

[0084] The degree of gelatinization was tested and found to be 48.6%.

[0085] Comparative Example 6

[0086] The only difference between Comparative Example 6 and Example 1 is that the mass of Qimen black tea powder in the raw materials of the kudzu root black tea drink in Comparative Example 1 is 1.0g.

[0087] The degree of gelatinization was tested and found to be 65.4%.

[0088] As can be seen from the gelatinization results of Example 1 and Comparative Examples 1-6, the gelatinization of the mixed powder prepared by the method of Example 1 reached a highly efficient, stable and controllable state (the gelatinization of Example 1 was as high as 95.8%); while the comparative examples 1-6, which did not use the method of this application, suffered from severe agglomeration, clumping or proportional antagonism, which resulted in water not being able to penetrate evenly, and the gelatinization was significantly lower and uncontrollable.

[0089] Test Example 1

[0090] The kudzu root black tea beverages prepared in Example 1 and Comparative Examples 1-6 were used as samples for mass spectrometry and chromatographic quantitative detection. The specific mass spectrometry and chromatographic quantitative detection methods are as follows:

[0091] (1) Sample pretreatment: Take the kudzu root black tea samples from each group, centrifuge at 12000 rpm for 10 min, take the supernatant and filter it through a 0.22 μm organic phase microporous membrane, and use the obtained filtrate as the test solution, and place it in a liquid chromatography-mass spectrometry instrument for detection.

[0092] (2) Chromatographic conditions: UPLC ultra-high performance liquid chromatography system was used. The chromatographic column was a C18 reversed-phase column (2.1 mm × 100 mm, 1.7 μm); the mobile phase A was 0.1% formic acid aqueous solution and the mobile phase B was acetonitrile; the flow rate was 0.3 mL / min; the column temperature was 40 ℃; the injection volume was 2 μL; gradient elution was performed.

[0093] (3) Mass spectrometry conditions: Electrospray ionization (ESI) was used, and multiple reaction monitoring (MRM) scanning was performed in both positive and negative ion monitoring modes. The capillary voltage was 3.0 kV, the desolvation gas temperature was 500 °C, and the desolvation gas flow rate was 800 L / h. Qualitative analysis was performed using the characteristic mass-to-charge ratio (m / z) of the parent ion and fragment ions of each target core active component, and the accurate chromatographic peak area of ​​each active ingredient was calculated using the external standard method.

[0094] The test results showed that the active components of the kudzu root black tea beverage included black tea polyphenols, such as kaempferol-3-O-rutin, epicatechin, theaflavins, rutin, neo-sennain, and isochlorogenic acid B, as well as kudzu root isoflavones, such as daidzein-4',7-diglucoside, 4',6,7-trihydroxyisoflavone-6-methyl ether-7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside, 4',5,7-trihydroxy-6-methoxyisoflavone-7-O-β-D-xylopyranosyl-(1→6)-β-D-glucopyranoside, malonyl daidzein, puerarin xyloside II, and puerarin C. The dissolution rates of each active component in the kudzu root black tea beverages of Example 1 and Comparative Examples 1-6 are shown in the appendix. Figure 1-12 .

[0095] Depend on Figure 1 It can be seen that the mass percentage content of kaempferol-3-O-rutin in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 ranges from 1.35% to 12.56%. Among them, the mass percentage content of kaempferol-3-O-rutin in Example 1 is 7.82%, which is second only to 12.56% in Comparative Example 6 and significantly higher than that in Comparative Examples 1-5. Kaempferol-3-O-rutin was not detected in Comparative Example 5.

[0096] Depend on Figure 2 It can be seen that the mass percentage content of epicatechin in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 of the present invention ranges from 0.09% to 13.97%. Among them, the mass percentage content of epicatechin in Example 1 is 7.78%, which is significantly higher than that in Comparative Examples 1-5.

[0097] Depend on Figure 3 It can be seen that the mass percentage content of theaflavins in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 ranges from 0.91% to 17.36%. Among them, the mass percentage content of theaflavins in Example 1 is 9.87%, which is significantly higher than that in Comparative Examples 1-5, and theaflavins were not detected in Comparative Example 5.

[0098] Depend on Figure 4It can be seen that the mass percentage content of daidzein-4',7-diglucoside in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 of the present invention ranges from 0.12% to 10.05%, of which the mass percentage content of daidzein-4',7-diglucoside in Example 1 is 5.45%, which is moderate.

[0099] Depend on Figure 5 It is known that the mass percentage content of 4',6,7-trihydroxyisoflavone-6-methyl ether-7-O-β-D-xylanopyranosyl-(1→6)-β-D-glucopyranoside in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 ranges from 3.42% to 9.36%. In Example 1, the mass percentage content of 4',6,7-trihydroxyisoflavone-6-methyl ether-7-O-β-D-xylanopyranosyl-(1→6)-β-D-glucopyranoside is 3.73%, while this substance was not detected in Comparative Example 6.

[0100] Depend on Figure 6 It can be seen that the mass percentage content of 4',5,7-trihydroxy-6-methoxyisoflavone-7-O-β-D-xylanopyranosyl-(1→6)-β-D-glucopyranoside in the kudzu root black tea of ​​Example 1 and Comparative Examples 1-6 ranges from 0.05% to 14.13%. Among them, the mass percentage content of 4',5,7-trihydroxy-6-methoxyisoflavone-7-O-β-D-xylanopyranosyl-(1→6)-β-D-glucopyranoside in Example 1 is 10.40%, which is second only to 14.13% in Comparative Example 6 and significantly higher than that in Comparative Examples 1-5. This substance was not detected in Comparative Examples 1-5.

[0101] Depend on Figure 7 It is known that the mass percentage content of malonyl daidzein in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 of the present invention ranges from 6.80% to 10.95%. Among them, the mass percentage content of malonyl daidzein in Example 1 is 8.19%, and malonyl daidzein was not detected in Comparative Examples 3 and Comparative Examples 5-6.

[0102] Depend on Figure 8 It can be seen that the mass percentage content of puerarin xylosinolate II in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 of the present invention ranges from 0.39% to 9.51%. Among them, the mass percentage content of puerarin xylosinolate II in Example 1 is 6.56%, and puerarin xylosinolate II was not detected in Comparative Example 5.

[0103] Depend on Figure 9 It can be seen that the mass percentage content of puerarin C in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 of the present invention ranges from 5.95% to 10.66%. Among them, the mass percentage content of puerarin C in Example 1 is 6.26%, and puerarin C was not detected in Comparative Examples 3 and Comparative Examples 5-6.

[0104] Depend on Figure 10 It can be seen that the mass percentage content of rutin in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 of the present invention ranges from 0.09% to 9.21%, and rutin was not detected in Example 1 and Comparative Example 3.

[0105] Depend on Figure 11 It can be seen that the mass percentage content of neo-North American senna in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 ranges from 2.36% to 13.31%. Among them, the mass percentage content of neo-North American senna in Example 1 is 6.86%, which is significantly higher than that in Comparative Examples 1-5. Neo-North American senna was not detected in Comparative Example 5.

[0106] Depend on Figure 12 It can be seen that the mass percentage of isochlorogenic acid B in the kudzu root black tea drinks of Example 1 and Comparative Examples 1-6 of the present invention ranges from 8.24% to 17.03%. Among them, the mass percentage of isochlorogenic acid B in Example 1 is 8.83%, and isochlorogenic acid B was not detected in Comparative Examples 2-3 and Comparative Examples 5-6.

[0107] The above test data shows that, with the dynamic changes in the ratio of Pueraria lobata powder to Qimen black tea powder in Example 1 and Comparative Examples 1-6, the dissolution of various core factors within the system exhibits a significant synergistic effect. Especially under the specific ratio in Example 1, not only is excellent stable physical integration demonstrated, but the balanced and maximized dissolution of the aforementioned Pueraria lobata isoflavone active components and the characteristic polyphenols and flavonoid active components of black tea is successfully achieved. This ratio effectively solves the problems of high viscosity aggregation and chemical antagonism between the two components under ultra-concentrated conditions, providing a crucial material basis for their subsequent role in regulating glucose and lipid metabolism and systemic anti-inflammatory effects in vivo.

[0108] Test Example 2

[0109] 1. Establishment of mouse model

[0110] C57BL / 6J mice (4-6 weeks old, male) were acclimatized for one week under standard conditions. They were then divided into four groups: normal group, normal group with tea, high-fat group, and high-fat group with tea, with five mice in each group.

[0111] Among them, the normal group and the normal group with added tea were fed standard maintenance diet, while the high-fat group and the high-fat group with added tea were fed high-fat and high-sugar diet (containing 60% fat energy ratio) to establish a high-fat mouse model.

[0112] During modeling, the normal tea-added group and the high-fat tea-added group were administered the sample described in Example 1 by gavage at a dose of 0.1 mL / 10 g body weight daily, while the normal group and the high-fat group were administered an equal volume of purified water by gavage daily. This gavage and feeding continued for a total of 12 weeks.

[0113] 2. Group processing

[0114] Mice in each group were administered gavage at a fixed time each day. The specific grouping and gavage methods are as follows:

[0115] Normal group: 0.2 mL of purified water was administered by gavage at regular intervals daily;

[0116] Normal tea addition group: 0.2 mL of the kudzu root black tea sample described in Example 1 was administered by gavage at regular intervals daily;

[0117] High-fat group: 0.2 mL of purified water was administered by gavage at regular intervals daily;

[0118] High-fat tea group: 0.2 mL of the kudzu root black tea sample described in Example 1 was administered by gavage at regular intervals each day.

[0119] 3. Indicator Testing

[0120] (1) Oral glucose tolerance test

[0121] After long-term intervention, mice in each group were fasted for 12 hours, during which time they were provided with normal drinking water. Subsequently, each group of mice was administered glucose solution by gavage at a dose of 0.2 mL. At 0, 15, 30, 60, 90, and 120 min after glucose gavage, tail vein blood samples were collected from each group of mice, and blood glucose values ​​were quantitatively measured and recorded at each time point using a glucometer.

[0122] After the experiment, the area under the curve (AUC) of glucose concentration change over time for each mouse during the entire experiment was calculated using the trapezoidal method to quantitatively assess the differences in glucose tolerance among the groups of mice.

[0123] (2) Serum biochemical index detection

[0124] After long-term modeling and intervention, blood samples were collected from mice in each group, centrifuged at 3000 rpm for 15 min at 4℃, and the supernatant was carefully aspirated to separate serum samples, which were then stored at -80℃ for later use.

[0125] Using a fully automated biochemical analyzer or a commercial enzyme immunoassay kit, and strictly following the instructions of the kit, the core lipid biochemical indicators such as low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) in the serum of mice in each group were accurately quantified.

[0126] (3) Detection of the content of pro-inflammatory cytokines and endotoxins

[0127] After the intervention, liver tissues of mice in each group were collected, accurately weighed, and added to pre-cooled physiological saline or PBS buffer at a ratio of tissue mass (g): homogenate (mL) = 1:9. After mechanical homogenization, the tissues were centrifuged at 3000 rpm for 10-15 min at 4℃, and the supernatant was collected as liver tissue homogenate samples for later use.

[0128] Commercially available enzyme immunoassay kits were used to detect the levels of endotoxin (LPS) in serum and local liver tissue. Simultaneously, a double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) kit was used, strictly following the kit instructions, to accurately determine the levels of endotoxin in mouse serum and local liver tissue, and to quantitatively detect the expression levels of core pro-inflammatory cytokines (interleukin-1β, interleukin-6, and tumor necrosis factor-α).

[0129] (4) Morphological observation of tissue sections

[0130] After the intervention, liver tissue samples were rapidly collected from each group of mice. The samples were washed with pre-cooled physiological saline to remove surface blood, blotted dry, and immediately immersed in 4% paraformaldehyde fixative for at least 24 hours. After fixation, the tissue samples were sequentially dehydrated with ethanol, cleared with xylene, and then embedded in paraffin. The embedded tissue blocks were then cut into continuous sections with a thickness of 4-5 μm using a paraffin microtome, unfolded, mounted on glass slides, and dried for later use.

[0131] Liver tissue sections from each group of mice were morphologically observed using hematoxylin-eosin (HE) staining. The tissue sections were examined in detail using a digital slide scanner at 2.0× low-power panoramic and 20.0× high-power local magnification, and typical fields of view were selected for comparative analysis. Results are shown in the appendix. Figure 19 .

[0132] 4. Test Results

[0133] (1) Effects of kudzu root black tea on glucose tolerance in mice

[0134] The results of the overall blood glucose exposure analysis are attached. Figure 13 From the appendix Figure 13 It can be seen that the area under the blood glucose curve in the high-fat group was as high as 1168.13 mmol / L·min, indicating that it had a severe pathological phenotype of impaired glucose tolerance; while the high-fat group with added tea, which was intervened with kudzu root black tea in Example 1, had its overall area under the blood glucose curve reduced to 904.05 mmol / L·min. Therefore, it can be seen that the kudzu root black tea in Example 1 has a very significant technical effect on stabilizing blood glucose and reducing overall glycemic load (P value less than 0.0001).

[0135] See the appendix for the results of the 120-minute continuous glucose fluctuation analysis. Figure 14The pairwise comparisons between the high-fat group and the high-fat plus tea group at specific monitoring time points are as follows: At the initial baseline period (0 min) before glucose loading, the fasting blood glucose level of mice in the high-fat plus tea group was significantly lower than that in the high-fat group (corrected P value less than 0.0001), confirming that the kudzu root black tea drink of Example 1 can fundamentally and long-term improve the fasting blood glucose baseline in mice on a high-fat diet. At the initial 15 min and 30 min of glucose loading, due to the plateau phase caused by the absorption of exogenous sugar into the blood, there was no statistically significant difference between the two groups (corrected P value at 30 min was 0.156). When the glucose loading reached 60 min, the acute regulatory advantage of the kudzu root black tea drink of Example 1 was stably released, and the blood glucose level of the high-fat plus tea group was significantly lower than that of the high-fat group (corrected P value less than 0.05). At the critical decline period of 90 min and 120 min in the later stage of glucose loading, the blood glucose level of mice in the high-fat plus tea group showed a cliff-like drop, significantly lower than that of the high-fat group (corrected P value less than 0.001).

[0136] The above data shows that the kudzu root black tea drink in Example 1 has the dual technical effects of long-term improvement of baseline fasting blood glucose and peak reduction regulation after acute glucose load.

[0137] (2) Effects of kudzu root black tea on serum biochemical indicators

[0138] The results of the detection of low-density lipoprotein cholesterol in mouse serum are shown in the appendix. Figure 15 .Depend on Figure 15 It is known that a long-term high-fat diet leads to a large accumulation of low-density lipoprotein cholesterol in the mice in the high-fat group, causing severe lipid metabolism disorders. In the high-fat group with kudzu root and black tea administered via gavage in Example 1, the serum low-density lipoprotein cholesterol level showed a precipitous drop compared to the high-fat group, with an absolute decrease of up to 0.55 mmol / L, which significantly reduced low-density lipoprotein cholesterol (P value less than 0.01).

[0139] The results of the detection of high-density lipoprotein cholesterol in mouse serum are shown in the appendix. Figure 16 .Depend on Figure 16 It was found that while LDL cholesterol decreased significantly, HDL cholesterol levels in the high-fat group with added tea showed a highly significant rebound, with the absolute serum HDL cholesterol content increasing by 1.965 mmol / L compared to the high-fat group (P < 0.001). Furthermore, a comparison between the normal group and the normal group with added tea showed that, under normal physiological conditions, the kudzu root black tea drink in Example 1 did not abnormally interfere with the body's lipid baseline, demonstrating excellent safety.

[0140] Based on the above biochemical data, it can be seen that the kudzu root black tea drink of Example 1 of the present invention does not only intervene in a single indicator in isolation, but can bidirectionally regulate and deeply repair the endogenous lipid metabolism homeostasis disorder induced by a high-fat diet, and fully demonstrates the excellent and safe technical efficacy of lowering lipids and protecting the cardiovascular system.

[0141] (3) Effects of kudzu root black tea on pro-inflammatory cytokines and endotoxins in mice

[0142] The results of the detection of local pro-inflammatory cytokines and endotoxins in mouse liver tissue are shown in the appendix. Figure 17 .Depend on Figure 17 It is evident that kudzu root black tea exhibits a strong ability to deeply intervene in the liver. Regarding hepatic interleukin-1β, the kudzu root black tea from Example 1 significantly inhibited the accumulation of hepatic interleukin-1β induced by a high-fat diet (P < 0.001). Experiments showed that the inflammatory factor levels in the high-fat plus tea group were not only far superior to those in the high-fat group, but also significantly lower than those in the normal group (P < 0.001). Regarding local hepatic interleukin-6, the kudzu root black tea from Example 1 showed universality in inhibiting interleukin-6, significantly downregulating the high-fat-induced hepatic interleukin-6 concentration (P < 0.001). Furthermore, under normal dietary conditions, the hepatic interleukin-6 concentration in the normal plus tea group was also significantly lower than that in the normal control group by approximately 34.4% (P < 0.001). Regarding local endotoxins in the liver, the kudzu root black tea drink in Example 1 showed a very significant endotoxin-reducing effect in the liver. Regardless of whether it was a high-fat diet or a standard diet, the liver endotoxin levels in the high-fat tea group and the normal tea group were significantly lower than those in the corresponding model group (P value less than 0.001), effectively reducing local toxin accumulation.

[0143] The results of the detection of systemic pro-inflammatory cytokines and endotoxins in mouse serum are shown in the appendix. Figure 18 .Depend on Figure 18It was found that the kudzu root black tea in Example 1 successfully blocked the spread of the inflammatory response from the liver to the systemic circulatory system by significantly downregulating the concentration of the pro-inflammatory factor interleukin-1β in serum (P value < 0.001). Simultaneously, in the serum interleukin-6 dimension, the kudzu root black tea in Example 1 significantly reduced the concentration of interleukin-6 in the circulatory system (P value < 0.001), demonstrating its significant advantage in improving systemic chronic inflammation. In the tumor necrosis factor-α dimension at the circulatory system level, the kudzu root black tea in Example 1 exhibited a robust interception effect. Serum tests showed that regardless of whether an individual was in a period of hyperlipidemia or normal physiological period, the intervention with the kudzu root black tea in Example 1 significantly reduced serum tumor necrosis factor-α levels (P value < 0.001); the reduction was most significant under normal dietary conditions, with a difference of 35.20 pg / mL between groups. Finally, regarding serum endotoxins, the intervention with kudzu root black tea in Example 1 significantly reduced the concentration in serum (P value less than 0.01), effectively blocking the occurrence of enterogenic endotoxemia. This finding provides key upstream mechanism support for the synergistic downregulation of all the aforementioned pro-inflammatory factors.

[0144] The above multi-dimensional biochemical indicators show that the kudzu root black tea drink of Example 1 of the present invention can build an excellent dual immune anti-inflammatory barrier for the body by intercepting endotoxin translocation at the source, deeply clearing local inflammatory factors in the liver, and completely blocking the spread of pro-inflammatory factors in the peripheral circulation system.

[0145] (4) Effects of kudzu root black tea on the morphology of mouse liver tissue

[0146] The specific pathological morphology of the liver tissue of each group of mice is as follows:

[0147] Normal control group and normal tea-added group: Results are shown in the appendix. Figure 19 A. Appendix Figure 19 B and appendix Figure 19 C. Appendix Figure 19 D. The tissue morphology of the two groups of mice showed a high degree of consistency. The liver capsule of both groups of mice was composed of dense connective tissue rich in elastic fibers of uniform thickness. The central vein was located in the center of the liver lobules, surrounded by hepatocytes and hepatic sinusoids arranged in a roughly radial pattern. Both groups showed widespread hepatocyte steatosis due to the physiological baseline, with tiny round vacuoles in the cytoplasm (black arrows), accompanied by a small amount of hepatocyte edema, manifested as loose and pale cytoplasm (red arrows), and a large amount of venous congestion (yellow arrows). No other obvious abnormalities were observed. The high degree of morphological similarity between the normal group with added tea and the normal control group confirms that the kudzu root black tea in Example 1 has no toxic side effects on the normal physiological structure of the body and has extremely high safety.

[0148] High-fat group: Results are attached. Figure 19 E and appendix Figure 19 F. The liver tissue capsule is composed of dense connective tissue of uniform thickness, rich in elastic fibers, and the lobule boundaries are indistinct. Under a microscope, extensive fatty degeneration of hepatocytes is visible, with tiny round vacuoles appearing in the cytoplasm (black arrows); occasional punctate necrosis of hepatocytes is observed within the lobules, accompanied by a small amount of inflammatory cell infiltration (red arrows); and extensive venous congestion is also visible (yellow arrows). These pathological damages confirm that a long-term high-fat diet has caused clear inflammatory damage to the liver parenchymal cells.

[0149] High-fat tea group: Results are shown in the appendix. Figure 19 G and appendix Figure 19 H. After simultaneous intervention with the kudzu root black tea described in Example 1, microscopic observation showed that although the group still exhibited significant hepatocyte steatosis (black arrows) and substantial venous congestion (yellow arrows) under a long-term high-fat diet, the punctate necrosis lesions and inflammatory cell infiltration commonly present in the high-fat model group completely disappeared, and no other obvious abnormalities were observed. The morphological results conclusively confirm that the kudzu root black tea of ​​Example 1 can target and block parenchymal cell necrosis, demonstrating excellent organ protection efficacy.

[0150] In summary, the kudzu root black tea drink of Example 1 has the effects of regulating glucose and lipid metabolism and anti-inflammatory effects. It can not only restore the metabolic balance of stabilizing blood sugar and lowering lipids, but also block the spread of inflammation in the whole body and the liver from the source, and achieve a multi-dimensional synergistic protective effect of completely reversing substantial inflammatory necrosis.

[0151] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0152] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for preparing a kudzu root black tea beverage, characterized in that, Includes the following steps: Kudzu root powder and black tea powder are mixed to obtain a mixed powder in which the black tea powder coats the kudzu root powder. Pure water at 90-100℃ is added to the mixed powder, and after stirring and standing extraction, the kudzu root black tea is obtained. The mass ratio of the mixed powder to the pure water is 1:15-25, and the gelatinization degree of the mixed powder is 80%-98%.

2. The preparation method according to claim 1, characterized in that, Place the kudzu root powder and the black tea powder in a dry powder mixer and stir for 2-10 minutes to obtain the mixed powder.

3. The preparation method according to claim 2, characterized in that, The stirring speed of the dry powder mixer is 100-500 rpm.

4. The preparation method according to claim 1, characterized in that, In the mixed powder, the mass percentage of kudzu root powder is 45-55%, and the mass percentage of black tea powder is 45-55%.

5. The preparation method according to claim 1, characterized in that, The kudzu root powder is selected from Bupleurum chinense root powder.

6. The preparation method according to claim 1, characterized in that, The black tea powder is selected from Qimen black tea powder.

7. The preparation method according to claim 1, characterized in that, The kudzu root powder has a particle size of 100-300 mesh, and the black tea powder has a particle size of 100-300 mesh; wherein the particle size ratio of the kudzu root powder to the black tea powder is 1:1-2.

8. The preparation method according to claim 1, characterized in that, The stirring time is 1-2 minutes.

9. The preparation method according to claim 1, characterized in that, The extraction time is 3-10 minutes.

10. A kudzu root black tea beverage prepared by the preparation method of any one of claims 1-9.

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