A tea extraction device and method of brewing tea

Abstract

The present application relates to the field of tea deep processing, and discloses a tea extraction liquid immersion type extraction device and method thereof, which comprises a fixed frame, a basket type immersion extraction mechanism is arranged beside the fixed frame, the basket type immersion extraction mechanism comprises an extraction immersion tank, an aeration type auxiliary extraction mechanism is arranged on the inner bottom of the extraction immersion tank, an extraction liquid discharge flow guide pipeline is fixedly connected to the bottom discharge end of the extraction immersion tank, and a centrifugal filtration mechanism is connected to the discharge end of the extraction liquid discharge flow guide pipeline in a butt joint mode. In the present application, three groups of series gradient variable speed centrifugal filtration mechanisms are arranged, a low-speed, medium-speed to high-speed step-up speed grading impurity removal process is adopted, the rotating speeds of the centrifugal mechanisms are independently regulated by frequency conversion, and the separation requirements of different particle size impurities are accurately matched; the first group of centrifugal filtration mechanisms is set to run at a low speed of 1500-2500 r / min, and the large particle tea dregs and coarse fiber materials in the tea soup are preferentially separated by a small centrifugal force.

Description

Technical Field

[0001] This invention relates to the field of deep processing of tea, and in particular to an immersion extraction device and method for tea extract. Background Technology

[0002] Tea extract is an intermediate product of deep processing of tea and is widely used in the production of tea drinks, solid tea powder, and tea beverages. Most existing immersion extraction equipment adopts the method of directly adding tea into the tank for immersion, resulting in tea residue mixed in the liquid and a large filtration load in the later stage. Some extraction equipment with baskets rely solely on static immersion, resulting in poor water flow in the tank, slow extraction rate of effective components of tea, and low extraction efficiency.

[0003] In existing technologies, the subsequent impurity removal of tea extracts mostly adopts single-stage centrifugal filtration. The single-stage centrifuge has a fixed speed, and under high-speed conditions, it is easy to shear and break large tea dregs, generating submicron-sized ultrafine colloidal particles. These colloids are difficult to filter out, which will cause the tea extract to become cloudy after cooling and to precipitate during storage. After centrifugal impurity removal, there is a lack of integrated equipment for deep membrane refining, instantaneous sterilization and aseptic filling. The resulting tea extract has a high impurity content, poor storage stability, large loss of flavor substances, and a short shelf life of the finished product. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide an immersion extraction device and method for tea extract to solve the problems of existing single-stage centrifugation which easily breaks tea residue into ultrafine colloids, easily causes turbidity and sedimentation of tea soup, and lacks integrated refining, sterilization and filling process, resulting in poor stability and shelf life of finished products.

[0005] To address the aforementioned problems, the present invention is implemented through the following technical solution.

[0006] An immersion extraction device and method for tea extract includes: a fixed frame; a basket-type immersion extraction mechanism is arranged beside the fixed frame; the basket-type immersion extraction mechanism includes an extraction immersion tank; an aeration-type auxiliary extraction mechanism is arranged at the bottom of the extraction immersion tank; an extract liquid discharge guide pipe is fixedly connected to the bottom discharge end of the extraction immersion tank; a centrifugal filtration mechanism is connected to the discharge end of the extract liquid discharge guide pipe; three sets of centrifugal filtration mechanisms are arranged; each centrifugal filtration mechanism includes a clarified liquid discharge port; a liquid transition buffer assembly is connected to the discharge end of the clarified liquid discharge port; and a controller is provided on the upper end of the fixed frame.

[0007] Preferably, the basket-type soaking and extraction mechanism further includes a basket body snap-fit ​​fixing plate, a material soaking basket, a basket limiting top plate, an inner limiting block, and a basket sealing end cap. The basket body snap-fit ​​fixing plate is fixedly installed on the inner side wall of the upper end of the extraction and soaking tank. The basket limiting top plate is fixedly installed on the upper part of the material soaking basket. The material soaking basket has a hollow mesh cylindrical structure. The top of the material soaking basket abuts against the bottom of the inner limiting block for limiting. The material soaking basket is vertically positioned and installed through the basket body snap-fit ​​fixing plate, and can be vertically disassembled and assembled along the basket body snap-fit ​​fixing plate inside the extraction and soaking tank.

[0008] Preferably, an inner limiting block is symmetrically fixed to the inner side of the upper end of the basket limiting top plate, and a basket sealing end cap is covered on the upper end of the inner side of the material soaking basket corresponding to the inner limiting block. The outer side of the basket sealing end cap is in close contact with the inner side of the basket limiting top plate, and the outer side of the basket limiting top plate is in close contact with the inner side of the top of the extraction soaking tank. The outer top surface of the basket sealing end cap is flush with the top surface of the basket limiting top plate and the top surface of the extraction soaking tank.

[0009] Preferably, the aeration-assisted extraction mechanism includes a sealing plate, microporous ceramic aeration plates, an air guide pipe, a pipe check valve, a Roots blower air supply pump, and a fixed mounting base. The sealing plate is fixedly installed at the bottom of the extraction soaking tank through the fixed mounting base, and the microporous ceramic aeration plates are fixedly installed on the upper surface of the sealing plate.

[0010] Preferably, a gas guide pipe is fixedly connected to the lower surface of the sealing support plate, and a pipeline check valve is installed in series on the pipeline section. One end of the gas guide pipe extending to the outside of the extraction soaking tank is connected to a Roots blower air supply pump. The microporous ceramic aeration plate is fixed to the upper surface of the sealing support plate in an arc-shaped protrusion. The air inlet end of the microporous ceramic aeration plate is connected to the gas guide pipe. The pipeline check valve is installed vertically in the middle section of the gas guide pipe to prevent the extract from flowing back into the Roots blower air supply pump.

[0011] Preferably, the centrifugal filtration mechanism includes a fixed support base, a drum end bearing seat, a drum drive belt, a drum main drive motor, a spiral end bearing seat, a spiral drive belt, a spiral pair drive motor, a spiral pusher, a feed port, a centrifugal drum, a solid filter residue discharge port, an outer shell, and a solid filter residue discharge pipeline. The fixed support base is fixed to the upper end of the fixed frame. The drum end bearing seat and the spiral end bearing seat are respectively fixedly installed at both ends of the fixed support base. The centrifugal drum is rotatably supported inside the drum end bearing seat. The output end of the drum main drive motor is connected to the centrifugal drum through the drum drive belt.

[0012] Preferably, a spiral pusher is coaxially rotatably supported inside the spiral end bearing seat. The spiral pusher is coaxially sleeved inside the centrifugal drum and has a clearance fit with the centrifugal drum. The output end of the spiral pair drive motor is connected to the spiral pusher via a spiral drive belt. A distribution port is provided in the middle of the spiral pusher. A clarified liquid outlet is provided in an annular arrangement at equal intervals at one end of the centrifugal drum near the spiral end bearing seat. A solid filter residue discharge port is provided in an annular arrangement at equal intervals at one end of the centrifugal drum away from the spiral end bearing seat. A solid filter residue discharge pipeline is connected and fixed to the outside of the solid filter residue discharge port. The centrifugal drum and the spiral pusher are covered by an outer shell, which is fixedly installed on the top of the fixed support base.

[0013] Preferably, the main drive motor of the centrifugal drum and the drive motor of the screw pair are independently fixed on both sides of the fixed support base. The centrifugal drum and the screw pusher are coaxially arranged and rotate independently. The drive belt of the drum and the drive belt of the screw are independently driven, so that the centrifugal drum and the screw pusher form an adjustable speed difference. The centrifugal filtration mechanism is provided in three sets. The three sets of centrifugal filtration mechanisms are connected in series along the direction of liquid flow. The working speed of the first set of centrifugal filtration mechanisms along the direction of liquid flow is set to 1500-2500 r / min, the working speed of the second set of centrifugal filtration mechanisms is set to 3000-4000 r / min, and the working speed of the third set of centrifugal filtration mechanisms is set to 4500-6000 r / min. The three sets of centrifugal filtration mechanisms are each equipped with an independent main drive motor of the drum and a drive motor of the screw pair, which are used to realize the independent speed adjustment of each centrifugal filtration mechanism.

[0014] Preferably, the feed liquid transition buffer assembly includes a feed delivery pipeline, the feed end of which is connected to the clarified liquid outlet, the discharge end of which is connected to a feed liquid buffer tank, the discharge end of which is connected to a discharge delivery pipeline fixedly at the bottom of the feed liquid buffer tank, a pipeline one-way valve fixedly connected in series on the discharge delivery pipeline section, and the discharge end of the discharge delivery pipeline connected to the next set of centrifugal filtration mechanisms.

[0015] An immersion extraction method for tea extract includes the following steps: S1. Basket-type closed constant temperature aeration soaking extraction: The tea raw materials are filled into the material soaking basket. The basket is vertically positioned by the basket body clamping and fixing plate on the inside of the extraction soaking tank. The basket is limited and fixed by the top limiting plate and the inner limiting block. The basket sealing end cover is closed to achieve tank sealing. Hot water for extraction is injected into the tank in advance. The extraction temperature is controlled at 75-95℃ by the tank steam jacket. The Roots blower is started. The airflow is delivered to the microporous ceramic aeration plate through the air guide pipe and the pipeline check valve. The micro-aeration disturbs the water body, enhances the dissolution of effective substances in the tea, and prevents the extract liquid from flowing back. After extraction, the material soaking basket is lifted to drain the liquid and clean the tea residue. The extract liquid is delivered to the next process through the extract liquid discharge guide pipe. S2. Three-stage gradient speed-controlled continuous centrifugal grading and impurity removal: The extract is transported to three sets of centrifugal filtration mechanisms connected in series. Each centrifugal filtration mechanism is independently driven by a main drive motor for the drum and a drive motor for the screw conveyor, creating an adjustable speed difference between the centrifugal drum and the screw conveyor to achieve continuous centrifugal sedimentation and automatic slag discharge. The liquid first enters the first set of centrifugal filtration mechanisms, running at a low speed of 1500-2500 r / min to remove large particles of tea residue and coarse fibers, avoiding the generation of ultrafine colloids by high-speed shearing. The discharged liquid enters the liquid buffer tank through the feed pipeline for stabilization. After pressure stabilization, the liquid is transported unidirectionally to the secondary equipment via a discharge pipeline equipped with a one-way valve. The second centrifugal filtration mechanism operates at a medium speed of 3000-4000 r / min to remove medium-sized tea dust and fine impurities. The discharged liquid is then pressure-stabilized and buffered again by the liquid-to-material transition buffer assembly and sent to the third centrifugal filtration mechanism, which operates at a high speed of 4500-6000 r / min to capture fine suspended particles and protein aggregates. The solid impurities separated at each stage are discharged through the solid filter residue discharge port and the solid filter residue discharge pipeline, ultimately yielding a low-turbidity clear tea liquid. S3. Nanofiltration Membrane Cross-flow Deep Refining and Purification: After three-stage gradient centrifugation and buffer pressure stabilization, the clarified tea liquor first passes through a 5-20μm pre-protection precision filter to intercept residual trace particles and protect the nanofiltration membrane element. The feed liquid is pressurized to 0.6-1.6MPa by a high-pressure feed pump and sent to a nanofiltration membrane pressure vessel with a built-in 200-800Da polyamide membrane element. Using a cross-flow filtration mode, relying on the membrane pore size sieving effect, water, tea polyphenols, theanine, and small-molecule aroma active substances are selectively permeated, while large-molecule pectin, crude protein, colloidal complexes, and other turbid impurities are retained. During the filtration process, part of the concentrate is recycled for purification, and high-impurity waste liquid is discharged periodically. The supporting sensing components monitor the operating conditions in real time, and the membrane flux is regenerated periodically with the CIP cleaning loop, finally obtaining a highly stable refined tea extract permeate. S4, UHT Ultra-High Temperature Instantaneous Sterilization: The nanofiltration-refined tea extract is sent to a UHT ultra-high temperature instantaneous sterilizer, preheated to 125-135℃ and held for 3-15 seconds to kill microorganisms and inactivate oxidases, inhibiting browning and deterioration of the tea soup; then it is rapidly cooled by heat exchange to retain the active substances and flavor of the tea to the maximum extent; the cooled sterile tea liquid is then sealed and transported to a sterile intermediate storage tank, where it is stored under nitrogen pressure to prevent oxidation and deterioration of the tea soup; S5. Aseptic Sealed Quantitative Filling and Storage: The refined tea extract in the aseptic temporary storage tank is transported to the aseptic filling unit through aseptic pipelines. Under the protection of the aseptic isolation hood and the SIP in-situ sterilization process, the precise quantitative filling is completed through the filling valve group. Then, the container is quickly sealed by the sealing capping mechanism to isolate it from external air and bacterial contamination, and finally, a finished tea extract with high clarity, pure flavor and long shelf life is obtained, completing the whole preparation process.

[0016] This invention provides an immersion extraction device and method for tea extract. Compared with the prior art, it has the following advantages: This invention employs three sets of series-connected gradient variable-speed centrifugal filtration mechanisms, using a step-by-step speed-increasing, graded impurity removal process from low to medium speed to high speed. Each centrifugal mechanism has its rotation speed independently controlled by frequency conversion to precisely match the separation requirements of impurities of different particle sizes. The first set of centrifugal filtration mechanisms operates at a low speed of 1500-2500 r / min, relying on relatively small centrifugal force to preferentially separate large tea dregs and coarse fibrous materials from the tea infusion. The low-speed operation avoids strong shearing and tearing effects, fundamentally avoiding the core defect of traditional one-step high-speed centrifugation that shreds tea dregs and generates difficult-to-remove nano and submicron-sized ultrafine colloids, thus solving the problem of subsequent clogging of nanofiltration membranes by ultrafine colloids. The second set of centrifugal filtration mechanisms operates at a medium speed of 3000-4000 r / min. The first centrifugal stage enhances centrifugal sedimentation force, precisely removing medium-sized tea particles and fine suspended impurities from the tea soup. The second centrifugal filtration unit operates at a high speed of 4500-6000 r / min, relying on ultra-large centrifugal force to capture and remove fine suspended particles and micro-protein aggregates from the tea soup, achieving step-by-step separation of impurities of all sizes (large, medium, and micro), significantly reducing the problems of cloudy tea soup after cooling and sedimentation during storage. At the same time, a feed transition buffer component is set between every two centrifugal stages, achieving stable pressure, stable flow, and uniform feed through the feed buffer tank, eliminating fluctuations in pipeline flow and pressure, and effectively preventing backflow of feed liquid with the help of pipeline one-way valves, ensuring constant feed conditions and stable and controllable separation effect for each centrifuge stage.

[0017] The system employs a detachable material soaking basket, which centrally holds the tea leaves. After extraction, the entire basket can be removed to drain the residue, preventing tea residue from remaining in the pipes and tank and simplifying the slag removal and cleaning process. The microporous ceramic aeration structure at the bottom of the tank uses microbubbles to agitate the water, enhancing the dissolution of effective substances from the tea leaves and improving extraction efficiency. The pipeline check valve prevents backflow of the liquid from damaging the air supply pump.

[0018] After multi-stage gradient centrifugation for impurity removal, a series nanofiltration cross-flow deep refining process is implemented. A 200-800 Da molecular weight cutoff polyamide nanofiltration membrane is used to achieve precise sieving under high-pressure cross-flow conditions of 0.6-1.6 MPa. It selectively allows water, tea polyphenols, theanine, small molecule aroma and other effective flavor and functional substances to pass through, while accurately retaining impurities that are prone to turbidity and precipitation, such as large molecule pectin, crude protein, and tea milk colloid complex. The front end is equipped with a 5-20 μm pre-protection precision filter, which can intercept residual hard particles in advance to effectively protect the nanofiltration membrane element. Combined with the CIP online cleaning loop, the membrane flux is restored in real time, which greatly extends the service life of the nanofiltration membrane. After nanofiltration refining, a UHT (ultra-high temperature instantaneous sterilization) process is employed. This process uses a short-term high-temperature sterilization at 125-135℃ for 3-15 seconds to kill bacteria, mold, and spores in the tea liquor and inactivate oxidases. Rapid heat exchange followed by cooling maximizes the preservation of the original aroma and active nutrients of the tea. The sterilized tea liquor is then passed into a sterile intermediate storage tank, where it is stored in a nitrogen-sealed, oxygen-free environment to inhibit oxidation and browning. Finally, aseptic filling using a sterile isolation hood and SIP (Self-Installation In-Place) sterilization process completes the sealing and bottling. The entire system integrates constant-temperature aeration immersion extraction, three-stage gradient variable-speed centrifugation for impurity removal, nanofiltration deep refining, UHT instantaneous sterilization, and aseptic bottling. The entire process is centrally controlled by a PLC controller, resulting in a compact workflow, high automation, and a finished tea extract with high clarity, no sediment, strong antioxidant capacity, and a longer shelf life. It is well-suited for the large-scale, continuous industrial production of high-quality tea extracts. Attached Figure Description

[0019] Figure 1 A schematic diagram of the overall three-dimensional structure of an immersion extraction device for tea extract.

[0020] Figure 2 This is a schematic diagram of the centrifugal filtration mechanism and the feed transition buffer assembly of an immersion extraction device for tea extract.

[0021] Figure 3 This is a schematic diagram of the exploded structure of the centrifugal filtration mechanism in an immersion extraction device for tea extract.

[0022] Figure 4 This is a schematic diagram of the extraction soaking tank and the aeration auxiliary extraction mechanism of the immersion extraction device for tea extract.

[0023] Figure 5 This is an exploded structural diagram of the aeration-assisted extraction mechanism and the basket-type soaking extraction mechanism for tea extract.

[0024] Figure 6 This is a schematic diagram of the aeration-assisted extraction mechanism in an immersion extraction device for tea extract.

[0025] Figure 7This is a schematic diagram of the immersion extraction method for tea extract.

[0026] The attached figures are labeled as follows: 1. Fixed frame; 2. Basket-type immersion extraction mechanism; 201. Extraction immersion tank; 202. Basket snap-fit ​​fixing plate; 203. Material immersion basket; 204. Basket limiting top plate; 205. Inner limiting block; 206. Basket sealing end cap; 3. Aeration-type auxiliary extraction mechanism; 301. Sealing support plate; 302. Microporous ceramic aeration plate; 303. Air guide pipe; 304. Pipeline check valve; 305. Roots blower air supply pump; 306. Fixed mounting base; 4. Extraction liquid discharge guide pipe; 5. Centrifugal filtration mechanism; 501. Fixed support base; 502. 503. Drum end bearing housing; 504. Drum drive belt; 505. Drum main drive motor; 506. Spiral end bearing housing; 507. Spiral drive belt; 508. Spiral pair drive motor; 509. Spiral pusher; 510. Distributor port; 511. Centrifugal drum; 512. Clarified liquid outlet; 513. Solid filter residue discharge port; 514. Outer shell; 515. Solid filter residue discharge pipeline; 6. Liquid transition buffer assembly; 601. Feed and liquid delivery pipeline; 602. Liquid buffer tank; 603. Discharge and liquid delivery pipeline; 604. Pipeline check valve; 7. Controller. Detailed Implementation

[0027] The present invention will be further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of protection of the present invention.

[0028] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0029] Reference Figures 1-7 An immersion extraction device and method for tea extract, comprising: a fixed frame 1, a basket-type immersion extraction mechanism 2 arranged beside the fixed frame 1, the basket-type immersion extraction mechanism 2 including an extraction immersion tank 201, an aeration-type auxiliary extraction mechanism 3 arranged at the bottom of the inner side of the extraction immersion tank 201, an extract liquid discharge guide pipe 4 fixedly connected to the bottom discharge end of the extraction immersion tank 201, a centrifugal filtration mechanism 5 connected to the discharge end of the extract liquid discharge guide pipe 4, three sets of centrifugal filtration mechanisms 5, each centrifugal filtration mechanism 5 including a clarified liquid discharge port 511, a liquid transition buffer assembly 6 connected to the discharge end of the clarified liquid discharge port 511, and a controller 7 arranged on the upper end of the fixed frame 1.

[0030] The basket-type soaking extraction mechanism 2 also includes a basket snap-fit ​​fixing plate 202, a material soaking basket 203, a basket limiting top plate 204, an inner limiting block 205, and a basket sealing end cap 206. The basket snap-fit ​​fixing plate 202 is fixedly installed on the inner wall of the upper end of the extraction soaking tank 201. The basket limiting top plate 204 is fixedly installed on the upper part of the material soaking basket 203. The material soaking basket 203 has a hollow mesh cylindrical structure. The top of the material soaking basket 203 abuts against the bottom of the inner limiting block 205 for limiting. The material soaking basket 203 is vertically positioned and installed through the basket snap-fit ​​fixing plate 202, and can be vertically disassembled and assembled along the basket snap-fit ​​fixing plate 202 inside the extraction soaking tank 201.

[0031] The inner side of the upper end of the basket limiting top plate 204 is symmetrically fixed with inner limiting blocks 205. The inner side of the material soaking basket 203 is covered with a basket sealing end cover 206 corresponding to the upper end of the inner limiting blocks 205. The outer side of the basket sealing end cover 206 is in close contact with the inner side of the basket limiting top plate 204. The outer side of the basket limiting top plate 204 is in close contact with the inner side of the top of the extraction soaking tank 201. The outer top surface of the basket sealing end cover 206 is flush with the top surface of the basket limiting top plate 204 and the top surface of the extraction soaking tank 201.

[0032] The aeration-type auxiliary extraction mechanism 3 includes a sealing plate 301, microporous ceramic aeration plates 302, an air guide pipe 303, a pipe check valve 304, a Roots blower air supply pump 305, and a fixed mounting base 306. The sealing plate 301 is fixedly installed at the bottom of the extraction soaking tank 201 through the fixed mounting base 306, and the microporous ceramic aeration plates 302 are fixedly installed on the upper surface of the sealing plate 301.

[0033] A gas guide pipe 303 is fixedly connected to the lower surface of the sealing plate 301. A pipe check valve 304 is installed in series on the gas guide pipe 303. One end of the gas guide pipe 303 extending to the outside of the extraction soaking tank 201 is connected to a Roots blower air supply pump 305. The microporous ceramic aeration plate 302 is fixed to the upper surface of the sealing plate 301 in an arc-shaped protrusion. The air inlet end of the microporous ceramic aeration plate 302 is connected to the gas guide pipe 303. The pipe check valve 304 is installed vertically in the middle section of the gas guide pipe 303 to prevent the extract from flowing back into the Roots blower air supply pump 305.

[0034] The centrifugal filtration mechanism 5 includes a fixed support 501, a drum end bearing seat 502, a drum drive belt 503, a drum main drive motor 504, a spiral end bearing seat 505, a spiral drive belt 506, a spiral pair drive motor 507, a spiral pusher 508, a distribution port 509, a centrifugal drum 510, a solid filter residue discharge port 512, an outer shell 513, and a solid filter residue discharge pipeline 514. The fixed support 501 is fixed to the upper end of the fixed frame 1. The drum end bearing seat 502 and the spiral end bearing seat 505 are fixedly installed at both ends of the fixed support 501, respectively. The centrifugal drum 510 is rotatably supported inside the drum end bearing seat 502. The output end of the drum main drive motor 504 is connected to the centrifugal drum 510 through the drum drive belt 503.

[0035] The spiral end bearing seat 505 is coaxially rotatably supported by a spiral pusher 508. The spiral pusher 508 is coaxially sleeved inside the centrifugal drum 510 and is clearance-fitted with the centrifugal drum 510. The output end of the spiral pair drive motor 507 is connected to the spiral pusher 508 through the spiral drive belt 506. The spiral pusher 508 has a distribution port 509 in the middle. The centrifugal drum 510 has a clarified liquid outlet 511 arranged in an annular shape at equal intervals at one end near the spiral end bearing seat 505. The centrifugal drum 510 has a solid filter residue discharge port 512 arranged in an annular shape at equal intervals at one end away from the spiral end bearing seat 505. A solid filter residue discharge pipe 514 is connected and fixed to the outside of the solid filter residue discharge port 512. The centrifugal drum 510 and the spiral pusher 508 are covered by an outer shell 513, which is fixedly installed on the top of the fixed support seat 501.

[0036] The main drive motor 504 of the drum and the drive motor 507 of the screw pair are independently fixed on both sides of the fixed support base 501. The centrifugal drum 510 and the screw pusher 508 are coaxially arranged and rotate independently. The drum drive belt 503 and the screw drive belt 506 drive independently, so that the centrifugal drum 510 and the screw pusher 508 form an adjustable speed difference. The centrifugal filtration mechanism 5 is provided in three sets. The three sets of centrifugal filtration mechanisms 5 are connected in series along the direction of liquid flow. The working speed of the first set of centrifugal filtration mechanisms 5 along the direction of liquid flow is set to 1500-2500 r / min, the working speed of the second set of centrifugal filtration mechanisms 5 is set to 3000-4000 r / min, and the working speed of the third set of centrifugal filtration mechanisms 5 is set to 4500-6000 r / min. The three sets of centrifugal filtration mechanisms 5 are equipped with independent main drive motors 504 and screw pair drive motors 507, which are used to realize the independent speed adjustment of each centrifugal filtration mechanism 5.

[0037] The feed liquid transition buffer assembly 6 includes a feed inlet pipeline 601, the feed end of which is connected to the clarified liquid outlet 511, the outlet end of which is connected to a feed liquid buffer tank 602, the bottom outlet end of which is connected to a discharge pipeline 603, a pipeline check valve 604 fixedly connected in series on the discharge pipeline 603, and the outlet end of the discharge pipeline 603 is connected to the next set of centrifugal filtration mechanisms 5.

[0038] An immersion extraction method for tea extract includes the following steps: S1. Basket-type closed constant temperature aeration soaking extraction: The tea raw material is filled into the material soaking basket 203. The basket 203 is vertically positioned by the basket body clamping and fixing plate 202 on the inner side of the extraction soaking tank 201. The basket is fixed by the basket limiting top plate 204 and the inner limiting block 205. The basket sealing end cover 206 is closed to seal the tank. Hot water for extraction is injected into the tank in advance. The extraction temperature is controlled at 75-95℃ by the tank steam jacket. The Roots blower air supply pump 305 is started. The airflow is delivered to the microporous ceramic aeration plate 302 through the air guide pipe 303 and the pipe check valve 304. The micro-aeration disturbs the water body, enhances the dissolution of effective substances in the tea, and prevents the extract from flowing back. After the extraction is completed, the material soaking basket 203 is lifted to drain the liquid and clean the tea residue. The extract is delivered to the next process through the extract discharge guide pipe 4. S2. Three-stage gradient speed-variable continuous centrifugal grading and impurity removal: The extract is transported to three sets of centrifugal filtration mechanisms 5 connected in series. Each centrifugal filtration mechanism 5 is independently driven by a main drive motor 504 for the drum and a drive motor 507 for the screw pair, so that the centrifugal drum 510 and the screw pusher 508 form an adjustable speed difference, realizing continuous centrifugal sedimentation and automatic slag discharge. The liquid first enters the first set of centrifugal filtration mechanisms 5, which runs at a low speed of 1500-2500 r / min to remove large tea dregs and coarse fibers, avoiding the generation of ultrafine colloids by high-speed shearing. The discharged liquid enters the liquid buffer tank 6 through the feed pipeline 601. After stabilizing the pressure and flow, the material is unidirectionally transported to the secondary equipment via the discharge and liquid delivery pipeline 603 with a pipeline check valve 604; the second centrifugal filtration mechanism 5 operates at a medium speed of 3000-4000 r / min to remove medium-sized tea dust and fine impurities; the material is then pressure-stabilized and buffered again by the material-liquid transition buffer component 6 and sent to the third centrifugal filtration mechanism 5, which operates at a high speed of 4500-6000 r / min to capture fine suspended particles and protein aggregates; the solid phase impurities separated at each stage are discharged through the solid phase filter residue discharge port 512 and the solid phase filter residue discharge pipeline 514, finally obtaining a low-turbidity clear tea liquid; S3. Nanofiltration Membrane Cross-flow Deep Refining and Purification: After three-stage gradient centrifugation and buffer pressure stabilization, the clarified tea liquor first passes through a 5-20μm pre-protection precision filter to intercept residual trace particles and protect the nanofiltration membrane element. The feed liquid is pressurized to 0.6-1.6MPa by a high-pressure feed pump and sent to a nanofiltration membrane pressure vessel with a built-in 200-800Da polyamide membrane element. Using a cross-flow filtration mode, relying on the membrane pore size sieving effect, water, tea polyphenols, theanine, and small-molecule aroma active substances are selectively permeated, while large-molecule pectin, crude protein, colloidal complexes, and other turbid impurities are retained. During the filtration process, part of the concentrate is recycled for purification, and high-impurity waste liquid is discharged periodically. The supporting sensing components monitor the operating conditions in real time, and the membrane flux is regenerated periodically with the CIP cleaning loop, finally obtaining a highly stable refined tea extract permeate. S4, UHT Ultra-High Temperature Instantaneous Sterilization: The nanofiltration-refined tea extract is sent to a UHT ultra-high temperature instantaneous sterilizer, preheated to 125-135℃ and held for 3-15 seconds to kill microorganisms and inactivate oxidases, inhibiting browning and deterioration of the tea soup; then it is rapidly cooled by heat exchange to retain the active substances and flavor of the tea to the maximum extent; the cooled sterile tea liquid is then sealed and transported to a sterile intermediate storage tank, where it is stored under nitrogen pressure to prevent oxidation and deterioration of the tea soup; S5. Aseptic Sealed Quantitative Filling and Storage: The refined tea extract in the aseptic temporary storage tank is transported to the aseptic filling unit through aseptic pipelines. Under the protection of the aseptic isolation hood and the SIP in-situ sterilization process, the precise quantitative filling is completed through the filling valve group. Then, the container is quickly sealed by the sealing capping mechanism to isolate it from external air and bacterial contamination, and finally, a finished tea extract with high clarity, pure flavor and long shelf life is obtained, completing the whole preparation process.

[0039] During use, the extraction and soaking tank 201 serves as the main extraction container. A basket is fixed to the inner wall of the upper end of the tank via a snap-fit ​​fixing plate 202. The material soaking basket 203 is integrally snap-fitted onto the basket fixing plate 202, achieving vertical positioning and detachable installation. The material soaking basket 203 has a perforated mesh structure for holding the tea raw materials, and its upper part is fixedly installed... The basket is limited by a top plate 204, and inner limiting blocks 205 are symmetrically fixed on the inner side of the upper end of the top plate 204. The top end face of the material soaking basket 203 abuts against the bottom end of the inner limiting blocks 205 to limit the material soaking basket 203 in both circumferential and vertical directions. The inner side of the upper end of the material soaking basket 203 is covered by a basket sealing end cap 206. The outer side wall of the basket sealing end cap 206 is tightly fitted with the inner side wall of the basket limiting top plate 204. The outer side wall of the basket limiting top plate 204 is fitted with the inner side wall of the top of the extraction soaking tank 201. The top surfaces of the basket sealing end cap 206 and the basket limiting top plate 204 are flush with the top surface of the extraction soaking tank 201 to ensure the overall airtightness of the tank.

[0040] During operation, the tea leaves are placed into the material soaking basket 203, and the entire basket is secured by the fixing plate 202. Hot water is injected into the extraction soaking tank 201 and maintained at a constant temperature of 75-95℃. Combined with bottom aeration and disturbance, the effective substances are dissolved. The basket is then sealed with the sealing end cap 206 to seal the tank opening. After extraction, the material soaking basket 203 can be vertically lifted and removed along the fixing plate 202 to achieve overall slag discharge, leaving no residue in the tank. The extracted liquid is then transported from the bottom outlet of the extraction soaking tank 201 to the next filtration process via the extraction liquid outlet guide pipe 4.

[0041] A sealing support plate 301 is fixedly installed at the bottom of the extraction and soaking tank 201 via a fixed mounting base 306. A microporous ceramic aeration plate 302 with an arc-shaped protrusion structure is fixed to the upper surface of the sealing support plate 301. A fixed air guide pipe 303 is connected to the lower surface of the sealing support plate 301. A pipe check valve 304 is installed vertically in series on the section of the air guide pipe 303. The outer end of the air guide pipe 303 is connected to a Roots blower air supply pump 305. During operation, the Roots blower air supply pump 305 generates high pressure. The airflow is guided through the air guide pipe 303 to the microporous ceramic aeration plate 302, where the microporous structure forms a large number of fine microbubbles, which evenly agitate the soaking water in the tank, enhancing the dissolution of tea polyphenols, theanine, and small aroma molecules. The pipeline check valve 304 is installed vertically in the middle of the pipeline, which can completely prevent the liquid inside the extraction soaking tank 201 from flowing back into the Roots blower air supply pump 305, preventing water from entering the pump and ensuring stable operation of the aeration extraction process.

[0042] Three sets of centrifugal filtration mechanisms 5 are arranged in series along the liquid flow direction. Each set of centrifugal filtration mechanism 5 is based on a fixed support 501. The fixed support 501 has a drum end bearing seat 502 and a spiral end bearing seat 505 fixed at its two ends, respectively. The drum end bearing seat 502 internally supports the centrifugal drum 510. The main drive motor 504 of the drum is connected to the centrifugal drum 510 through a drum drive belt 503, driving the centrifugal drum 510 to rotate at high speed. The spiral end bearing seat 505 internally coaxially supports the spiral pusher 508. The spiral pusher 508 is coaxially fitted inside the centrifugal drum 510. The spiral pair drive motor 507 independently drives the spiral pusher 508 to rotate through a spiral drive belt 506. Centrifugal drum 5 The centrifugal drum 510 and the screw feeder 508 are driven independently by two motors, forming a stable and adjustable speed difference to achieve continuous centrifugal sedimentation and automatic slag discharge. A distribution port 509 is opened in the middle of the screw feeder 508, through which the liquid material enters the centrifugal drum 510 for centrifugal separation. The centrifugal drum 510 has a ring-shaped and uniformly distributed clarified liquid outlet 511 near the screw end bearing seat 505 for discharging the clarified liquid. The centrifugal drum 510 has a ring-shaped and uniformly distributed solid phase filter residue discharge port 512 away from the screw end bearing seat 505. The solid phase filter residue discharge port 512 is connected to a solid phase filter residue discharge pipeline 514 to achieve centralized discharge of waste residue. The centrifugal drum 510 and the screw feeder 508 are covered by an outer shell 513 to achieve sealed and splash-proof operation.

[0043] The three centrifugal filtration units 5 employ a gradient speed-increasing classification and impurity removal logic, with parameters increasing progressively: the first centrifugal filtration unit 5 operates at a low speed of 1500-2500 r / min, using low shear centrifugal force to separate large tea dregs and coarse fibers, preventing the tea dregs from being sheared and broken into ultrafine colloids; the second centrifugal filtration unit 5 operates at a medium speed of 3000-4000 r / min, removing medium-sized tea dregs and fine suspended impurities; the third centrifugal filtration unit 5 operates at a high speed of 4500-6000 r / min, capturing fine suspended particles and protein aggregates, achieving classification and removal of impurities of all particle sizes.

[0044] A set of liquid transition buffer components 6 is set between each pair of adjacent centrifugal filtration units 5. The feed inlet of the liquid transition buffer component 6 is connected to the clarified liquid outlet 511 of the previous centrifugal filtration unit 5. The outlet of the feed inlet of the liquid ...

[0045] After undergoing three-stage gradient centrifugation and pressure stabilization to remove impurities, the low-turbidity tea liquor first passes through a 5-20μm pre-protection precision filter to intercept residual hard particles and protect the downstream membrane element. The liquor is then pressurized to 0.6-1.6MPa by a high-pressure feed pump and sent to a pressure vessel containing a 200-800Da polyamide nanofiltration membrane element. A cross-flow filtration method is used to selectively allow tea polyphenols, theanine, and small-molecule aroma molecules to pass through, while retaining large-molecule pectin, crude protein, colloidal complexes, and other turbid impurities. A portion of the concentrate is recycled for further purification, and waste liquid is periodically discharged. Combined with a CIP cleaning circuit, the membrane flux is continuously ensured to obtain a highly clear refined tea extract.

[0046] The refined tea liquid is fed into an UHT ultra-high temperature instantaneous sterilization equipment, where it is kept at 125-135℃ for 3-15 seconds to achieve thorough sterilization and inactivation of oxidases. Then, it is rapidly cooled to lock in the aroma. The cooled aseptic tea liquid enters an aseptic intermediate storage tank and is stored in a nitrogen-sealed environment to prevent oxidation and browning. Finally, it is transported to the aseptic filling unit through aseptic pipelines, where quantitative filling and capping are completed in an aseptic isolation hood and SIP in-situ sterilization environment, ultimately obtaining a highly stable finished tea extract with a long shelf life.

[0047] The controller 7 installed on the upper end of the fixed frame 1 electrically links the Roots blower air supply pump 305, the main drive motor 504 and the screw pair drive motor 507 of the three centrifugal mechanisms, the nanofiltration system, the sterilization unit and the filling equipment, so as to realize the sequential linkage of the entire process of extraction aeration, gradient centrifugation speed change, pressure stabilization feeding, membrane purification, sterilization and filling, the parameter adjustment, and the fault interlock, so as to realize the fully automatic continuous high-quality production of tea extract.

[0048] Therefore, although the invention has been described herein with reference to specific embodiments thereof, freedom of modification, various changes and substitutions are also within the scope of the foregoing disclosure, and it should be understood that in some cases, certain features of the invention may be adopted without departing from the scope and spirit of the invention and without corresponding use of other features. Thus, many modifications can be made to adapt a particular environment or material to the essential scope and spirit of the invention. The invention is not intended to be limited to the specific terminology used in the following claims and / or the specific embodiments disclosed as the best mode for carrying out the invention, but the invention will include any and all embodiments and equivalents falling within the scope of the appended claims. Therefore, the scope of the invention will be defined only by the appended claims.

Claims

1. An immersion extraction device for tea extract, characterized in that, include: A fixed frame (1) is provided with a basket-type soaking extraction mechanism (2) on the side of the fixed frame (1). The basket-type soaking extraction mechanism (2) includes an extraction soaking tank (201). An aeration-type auxiliary extraction mechanism (3) is provided at the bottom of the inner side of the extraction soaking tank (201). An extraction liquid discharge guide pipe (4) is fixedly connected to the bottom discharge end of the extraction soaking tank (201). A centrifugal filtration mechanism (5) is connected to the discharge end of the extraction liquid discharge guide pipe (4). The centrifugal filtration mechanism (5) is provided with three sets. The centrifugal filtration mechanism (5) includes a clarified liquid discharge port (511). A liquid transition buffer component (6) is connected to the discharge end of the clarified liquid discharge port (511). A controller (7) is provided at the upper end of the fixed frame (1). The centrifugal filtration mechanism (5) includes a fixed support base (501), a drum end bearing seat (502), a drum drive belt (503), a drum main drive motor (504), a spiral end bearing seat (505), a spiral drive belt (506), a spiral pair drive motor (507), a spiral pusher (508), a distribution port (509), a centrifugal drum (510), a solid filter residue discharge port (512), an outer shell (513), and a solid filter residue discharge pipeline (514). The fixed support base (501) is fixed to the upper end of the fixed frame (1). The drum end bearing seat (502) and the spiral end bearing seat (505) are fixedly installed at both ends of the fixed support base (501). The centrifugal drum (510) is rotatably supported inside the drum end bearing seat (502). The output end of the drum main drive motor (504) is connected to the centrifugal drum (510) through the drum drive belt (503). The main drive motor (504) of the rotating drum and the drive motor (507) of the screw pair are both independently fixed on both sides of the fixed support base (501). The centrifugal rotating drum (510) and the screw pusher (508) are coaxially arranged and rotate independently. The rotating drum drive belt (503) and the screw drive belt (506) are driven independently, so that the centrifugal rotating drum (510) and the screw pusher (508) form an adjustable speed difference. The centrifugal filtration mechanism (5) is provided in three sets, and the three sets of centrifugal filtration mechanisms (5) are connected in series along the direction of liquid flow. The working speed of the first centrifugal filtration mechanism (5) along the flow direction of the liquid is set to 1500-2500 r / min, the working speed of the second centrifugal filtration mechanism (5) is set to 3000-4000 r / min, and the working speed of the third centrifugal filtration mechanism (5) is set to 4500-6000 r / min. The three centrifugal filtration mechanisms (5) are respectively equipped with independent main drive motor (504) for the drum and drive motor (507) for the independent speed adjustment of each centrifugal filtration mechanism (5). The feed liquid transition buffer assembly (6) includes a feed delivery pipeline (601), the feed end of which is connected to the clarified liquid outlet (511), the discharge end of which is connected to a feed liquid buffer tank (602), the discharge end of which is connected to a discharge delivery pipeline (603), a pipeline check valve (604) fixedly connected to the pipeline section of the discharge delivery pipeline (603), and the discharge end of the discharge delivery pipeline (603) is connected to the next set of centrifugal filtration mechanisms (5).

2. The immersion extraction device for tea extract according to claim 1, characterized in that, The basket-type soaking extraction mechanism (2) also includes a basket snap-fit ​​fixing plate (202), a material soaking basket (203), a basket limiting top plate (204), an inner limiting block (205), and a basket sealing end cap (206). The basket snap-fit ​​fixing plate (202) is fixedly installed on the inner wall of the upper end of the extraction soaking tank (201). The basket limiting top plate (204) is fixedly installed on the upper part of the material soaking basket (203). The material soaking basket (203) is a hollow mesh cylindrical structure. The top of the material soaking basket (203) abuts against the bottom of the inner limiting block (205) for limiting. The material soaking basket (203) is vertically positioned and installed through the basket snap-fit ​​fixing plate (202), and can be vertically disassembled and assembled along the basket snap-fit ​​fixing plate (202) inside the extraction soaking tank (201).

3. The immersion extraction device for tea extract according to claim 2, characterized in that, The basket limiting top plate (204) is symmetrically fixed with inner limiting blocks (205) on the inner side of the upper end. The material soaking basket (203) is covered with a basket sealing end cap (206) on the upper end of the inner limiting block (205). The outer side of the basket sealing end cap (206) is in contact with the inner side of the basket limiting top plate (204). The outer side of the basket limiting top plate (204) is in contact with the inner side of the top of the extraction soaking tank (201). The outer top surface of the basket sealing end cap (206) is flush with the top surface of the basket limiting top plate (204) and the top surface of the extraction soaking tank (201).

4. The immersion extraction device for tea extract according to claim 1, characterized in that, The aeration-type auxiliary extraction mechanism (3) includes a sealing plate (301), microporous ceramic aeration plates (302), an air guide pipe (303), a pipe check valve (304), a Roots blower air supply pump (305), and a fixed mounting base (306). The sealing plate (301) is fixedly installed at the bottom of the extraction soaking tank (201) through the fixed mounting base (306), and the microporous ceramic aeration plates (302) are fixedly installed on the upper surface of the sealing plate (301).

5. The immersion extraction device for tea extract according to claim 4, characterized in that, The lower surface of the sealing plate (301) is connected to and fixed with a gas guide pipe (303). A pipe check valve (304) is installed in series on the pipe section of the gas guide pipe (303). One end of the gas guide pipe (303) extending to the outside of the extraction soaking tank (201) is connected to a Roots blower air supply pump (305). The microporous ceramic aeration plate (302) is fixed to the upper surface of the sealing plate (301) in an arc-shaped protrusion. The air inlet end of the microporous ceramic aeration plate (302) is connected to the gas guide pipe (303). The pipe check valve (304) is installed vertically in the middle section of the gas guide pipe (303) to prevent the extract liquid from flowing back into the Roots blower air supply pump (305).

6. The immersion extraction device for tea extract according to claim 1, characterized in that, The spiral end bearing housing (505) coaxially supports a spiral pusher (508). The spiral pusher (508) is coaxially sleeved inside the centrifugal drum (510) and has a clearance fit with the centrifugal drum (510). The output end of the spiral drive motor (507) is connected to the spiral pusher (508) via a spiral drive belt (506). The spiral pusher (508) has a material distribution port (509) in the middle. The centrifugal drum (510) is close to the spiral end bearing housing (505). One end of the centrifugal drum (510) is provided with a clarified liquid outlet (511) in an annular shape at equal intervals. The end of the centrifugal drum (510) away from the spiral end bearing seat (505) is provided with a solid phase filter residue discharge port (512) in an annular shape at equal intervals. A solid phase filter residue discharge pipeline (514) is connected and fixed to the outside of the solid phase filter residue discharge port (512). The centrifugal drum (510) and the spiral pusher (508) are covered with an outer shell (513). The outer shell (513) is fixedly installed on the top of the fixed support base (501).

7. An immersion extraction method for tea extract, applied to the immersion extraction apparatus for tea extract as described in any one of claims 1-6, characterized in that: Includes the following steps: S1. Basket-type closed constant temperature aeration soaking extraction: The tea raw materials are filled into the material soaking basket (203). The basket (203) is vertically positioned by the basket body clamping and fixing plate (202) inside the extraction soaking tank (201). The basket is fixed by the basket limiting top plate (204) and the inner limiting block (205). The basket sealing end cover (206) is closed to achieve tank sealing. Hot water for extraction is injected into the tank in advance, and the extraction is carried out by the steam in the tank. The jacket is used to control the extraction temperature at 75-95℃. The Roots blower pump (305) is started, and the airflow is delivered to the microporous ceramic aeration plate (302) through the air guide pipe (303) and the pipe check valve (304). The micro-aeration disturbs the water body, enhances the dissolution of effective substances in tea, and prevents backflow of the extract. After the extraction is completed, the material soaking basket (203) is lifted to drain the liquid and clean the tea residue. The extract is delivered to the next process through the extract discharge guide pipe (4). S2. Three-stage gradient speed-variable continuous centrifugal grading and impurity removal: The extract is transported to three sets of centrifugal filtration mechanisms (5) connected in series. Each centrifugal filtration mechanism (5) is driven independently by the main drive motor (504) of the drum and the drive motor (507) of the screw pair, so that the centrifugal drum (510) and the screw pusher (508) form an adjustable speed difference to achieve continuous centrifugal sedimentation and automatic slag discharge. The liquid first enters the first set of centrifugal filtration mechanisms (5) and runs at a low speed of 1500-2500r / min to remove large tea dregs and coarse fibers, and avoid high-speed shearing to generate super-fine particles. Fine colloids; the material is fed into the feed liquid buffer tank (602) through the feed liquid pipeline (601) and then stabilized in pressure and flow. It is then transported unidirectionally to the secondary equipment through the discharge liquid pipeline (603) with the pipeline check valve (604); the second set of centrifugal filtration mechanism (5) operates at a medium speed of 3000-4000r / min to remove medium-sized tea dust and fine impurities; the material is then fed into the third set of centrifugal filtration mechanism (5) after being stabilized and buffered again by the feed liquid transition buffer component (6), and then operates at a high speed of 4500-6000r / min to capture fine suspended particles and protein aggregates; The solid impurities separated at each stage are discharged through the solid filter residue discharge port (512) and the solid filter residue discharge pipeline (514) to finally obtain a clear tea liquid with low turbidity. S3. Nanofiltration Membrane Cross-flow Deep Refining and Purification: After three-stage gradient centrifugation and buffer pressure stabilization, the clarified tea liquid first passes through a 5-20μm pre-protected precision filter to intercept residual trace particles and protect the nanofiltration membrane element. The liquid is then pressurized to 0.6-1.6MPa by a high-pressure feed pump and sent to a nanofiltration membrane pressure vessel containing a 200-800Da polyamide membrane element. Using a cross-flow filtration mode, relying on the membrane pore size sieving effect, water, tea polyphenols, theanine, and small-molecule aroma active substances are selectively allowed to pass through, while large-molecule pectin, crude protein, colloidal complexes, and other turbid impurities are retained. During the filtration process, part of the concentrate is recycled for further purification, and high-impurity waste liquid is discharged periodically. The matching sensing components monitor the operating conditions in real time, and the membrane flux is regenerated periodically with the CIP cleaning circuit, ultimately obtaining a highly stable refined tea extract permeate; S4, UHT Ultra-High Temperature Instantaneous Sterilization: The nanofiltration-refined tea extract is sent to a UHT ultra-high temperature instantaneous sterilizer, preheated to 125-135℃ and held for 3-15 seconds to kill microorganisms and inactivate oxidases, inhibiting browning and deterioration of the tea soup; then it is rapidly cooled by heat exchange to retain the active substances and flavor of the tea to the maximum extent; the cooled sterile tea liquid is then sealed and transported to a sterile intermediate storage tank, where it is stored under nitrogen pressure to prevent oxidation and deterioration of the tea soup; S5. Aseptic Sealed Quantitative Filling and Storage: The refined tea extract in the aseptic temporary storage tank is transported to the aseptic filling unit through aseptic pipelines. Under the protection of the aseptic isolation hood and the SIP in-situ sterilization process, the precise quantitative filling is completed through the filling valve group. Then, the container is quickly sealed by the sealing capping mechanism to isolate it from external air and bacterial contamination, and finally, a finished tea extract with high clarity, pure flavor and long shelf life is obtained, completing the whole preparation process.

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