Continuous automatic device capable of improving flash extraction quality of coffee

Abstract

The utility model belongs to the technical field of instant coffee, and particularly discloses a continuous automatic device capable of improving flash extraction quality of coffee. A discharging port I of a feeding unit and a water outlet of a water supply unit of the device are communicated with a feeding port II of a screw conveyor, an extraction unit comprises a first-stage flash extraction tank, a second-stage flash extraction tank and a second-stage pump, the discharging port II of the screw conveyor is communicated with a feeding port III of the first-stage flash extraction tank, and a discharging port III of the first-stage flash extraction tank is communicated with a feeding port IV of the second-stage flash extraction tank through the second-stage pump. A filter screen is arranged in the secondary flash extraction tank, a filtrate outlet is communicated with a water inlet of the cooler, a water outlet of the cooler is communicated with the storage tank, and the material supply unit, the water supply unit, the screw conveyor and the secondary pump are electrically connected with the control system. According to the utility model, the screw conveyor is combined with the two-stage flash extraction tank structure for infiltration, excessive extraction can be avoided through the control system, the flash extraction quality is improved, the extraction time is shortened, the extract yield is improved, and the device has the characteristics of simple structure, good extract quality, short extraction time and high powder yield.

Description

Technical Field

[0001] The utility model belongs to the technical field of instant coffee, and specifically relates to a continuous automatic device which has simple structure, good extraction quality, short extraction time, high powder yield and can improve the coffee flash extraction quality. Background Art

[0002] Coffee products are mainly divided into instant, ready-to-drink and freshly ground coffee. Among them, instant coffee is a dry coffee extract obtained by evaporating the water in the coffee extract. Since instant coffee can be quickly dissolved in hot water, it is simpler than the complicated brewing method of ready-to-drink and freshly ground coffee, and it occupies less space and volume during storage and transportation, and is more durable in storage, so it has gained widespread popularity. As coffee consumers continue to pursue high-quality coffee, the demand for high-quality instant coffee powder has increased.

[0003] At present, the production process of instant coffee powder mainly includes roasting, crushing, extraction, hot concentration and freeze drying or spray drying. Among them, the coffee extraction stage is the key link to determine the quality of instant coffee powder, but currently high temperature and high pressure extraction is mostly used, and in order to obtain a higher powder yield, the coffee extraction time is as long as more than 300 minutes. The long-term high temperature and high pressure extraction not only causes the extraction of bad flavor substances in the coffee, but also destroys some aroma and nutrients in the coffee, resulting in poor quality of the extracted instant coffee powder, making it difficult to increase the added value of coffee.

[0004] For this reason, a flash coffee process has emerged in the prior art, which uses hot water to quickly extract coffee powder, and then adds ice cubes or rapidly cools it down to make cold coffee. The flash coffee process cools the hot coffee in a very short time, which can effectively lock in the aroma components produced when the hot coffee is extracted, and prevent the bad flavor substances in the coffee from being extracted. At the same time, it can also minimize the occurrence of oxidation reactions, giving the coffee an excellent flavor. However, the existing flash coffee equipment mostly adopts an infiltration-filtering extraction structure. Although the structure is relatively simple, its structure only allows intermittent flash extraction, which makes its flash extraction efficiency low. In addition, since it is difficult for water to penetrate into the compacted coffee powder, it is difficult to fully extract the coffee powder, resulting in the final extraction liquid being of low quality and serious waste of coffee powder. It is generally only used in household coffee machines. In addition, there is also a rotatable porous powder tray combined with an upper parallel water supply, powder supply and slag discharge system. The porous powder tray rotates to simultaneously realize loading, extraction and slag discharge, which not only avoids the problem of water having difficulty in penetrating into the coffee powder, but also avoids the waiting time for loading and slag discharge, thereby improving the extraction efficiency, and can also balance the quality of the extract and the extraction rate by controlling the rotation speed of the porous powder tray; but since the porous powder tray needs to rotate and switch between loading, extraction and slag discharge, it is difficult to effectively seal during extraction, and it is easy to cause the aroma components produced during extraction to be oxidized and reduce the quality of the extract, and since the coffee powder and hot water are relatively still during the extraction process, the extraction temperatures of the coffee powder in the middle and at the edge are significantly different, making it difficult for the coffee powder to be effectively extracted, and its extraction process is still intermittent extraction, and its extraction efficiency is relatively low. Utility Model Content

[0005] In order to overcome the deficiencies of the prior art, the utility model develops a continuous automatic device which has a simple structure, good extraction quality, short extraction time, high powder yield and can improve the quality of coffee flash extraction.

[0006] The utility model is implemented as follows: it includes a feeding unit, a water supply unit, a screw conveyor, an extraction unit, a cooler, a storage tank, and a control system. The discharge port I of the feeding unit and the water outlet of the water supply unit are respectively connected to the feed port II of the screw conveyor. The extraction unit includes a primary flash extraction tank, a secondary flash extraction tank, and a secondary pump. The discharge port II of the screw conveyor is connected to the feed port III of the primary flash extraction tank. The discharge port III of the primary flash extraction tank is connected to the feed port IV of the secondary flash extraction tank through the secondary pump. A filter is provided in the secondary flash extraction tank. The filtrate outlet of the secondary flash extraction tank is connected to the water inlet of the cooler. The water outlet of the cooler is connected to the storage tank. The feeding unit, the water supply unit, the screw conveyor and the secondary pump are respectively electrically connected to the control system.

[0007] Furthermore, the first-stage flash extraction tank and the second-stage flash extraction tank are both cylindrical closed percolation tanks, and a spiral guide plate is fixedly arranged in the inner cavity of the percolation tank from top to bottom, and the discharge port II of the screw conveyor is connected with the feed port III at the top of the first-stage flash extraction tank, and the discharge port III at the bottom of the first-stage flash extraction tank is connected with the feed port IV at the top of the second-stage flash extraction tank through a second-stage pump.

[0008] Furthermore, an inverted cone-shaped liquid storage cavity is provided at the bottom of the first-stage flash extraction tank, and a discharge port III of the first-stage flash extraction tank is provided at the bottom of the liquid storage cavity.

[0009] Furthermore, the filter screen is an inverted cone filter screen and is arranged at the lower part of the secondary flash extraction tank, the open end of the filter screen is tightly connected to the inner wall of the secondary flash extraction tank, and the filtrate outlet is arranged outside the filter screen at the bottom of the secondary flash extraction tank.

[0010] Furthermore, an extruder is provided below the secondary flash extraction tank, and a coffee grounds straight tube is provided at the lower end of the filter screen in the secondary flash extraction tank, the top end of the coffee grounds straight tube is connected with the bottom of the filter screen, the lower part of the coffee grounds straight tube passes through the bottom wall of the secondary flash extraction tank and is connected with the feed port V of the extruder, the liquid outlet I of the extruder is connected with the water inlet of the cooler through a recovery liquid pump, and the extruder and the recovery liquid pump are electrically connected to the control system respectively.

[0011] Furthermore, a fine filter is provided between the secondary flash extraction tank and the cooler, the filtrate outlet of the secondary flash extraction tank is connected to the liquid inlet of the fine filter through a liquid outlet pump, the liquid outlet I of the extruder is connected to the liquid inlet of the fine filter through a recovery liquid pump, the liquid outlet II of the fine filter is connected to the water inlet of the cooler, and the liquid outlet pump is electrically connected to the control system.

[0012] Furthermore, the feeding unit includes a raw material bin and a screw metering machine. The raw material bin is fixedly arranged above the screw metering machine, and the screw metering machine is arranged above the screw conveyor. The discharge port IV of the raw material bin is connected with the feed port VI of the screw metering machine, and the discharge port VI of the screw metering machine is connected with the feed port II of the screw conveyor through a pipeline, and the screw metering machine is electrically connected to the control system.

[0013] Furthermore, an electric valve is provided on the connecting pipeline between the discharge port VI of the screw metering machine and the feed port II of the screw conveyor, and the electric valve is electrically connected to the control system.

[0014] Furthermore, the water supply unit includes a water tank, a high-pressure variable frequency pump, a flow meter, and a heater which are connected in sequence, and the high-pressure variable frequency pump, the flow meter, and the heater are electrically connected to the control system respectively.

[0015] Compared with the prior art, the beneficial effects of the utility model are:

[0016] 1. The utility model adopts a screw conveyor to soak the coffee powder, and then extracts the soaked coffee powder through a two-stage flash extraction tank. At the same time, the control system automatically controls the time and temperature of feeding, water supply, soaking and extraction, thereby avoiding over-extraction and reducing oxidation reactions caused by traditional high temperature and high pressure, improving the quality of instant coffee powder, and realizing continuous extraction, effectively improving the extraction efficiency. It is particularly suitable for the industrial production of instant coffee powder and is also suitable for use in commercial coffee machines with large flow rates.

[0017] 2. The utility model adopts the extraction structure of screw conveyor infiltration + two-stage flash extraction tank, and a spiral guide plate is arranged in the flash extraction tank, so that the coffee powder is dynamically mixed with hot water during the extraction process, which can not only increase the dissolution rate of effective cost in the coffee powder to improve the extraction efficiency, but also make the extraction temperature of the coffee powder more uniform to improve the extraction quality, and the infiltration + two-stage flash extraction structure can form different extraction temperatures, so as to maintain the excellent flavor of the coffee given by the flash extraction, but also can extract the beneficial substances in the coffee powder as much as possible through the temperature gradient, effectively taking into account the quality of the extract and the powder yield.

[0018] 3. The screw conveyor infiltration + two-stage flash extraction tank and the subsequent cooler of the utility model are all closed structures, which can not only avoid the dissipation of aroma substances during the coffee flash extraction process, but also minimize the contact between the flash extraction materials and the air. Combined with the lower flash extraction temperature, it can effectively slow down the occurrence of oxidation reactions during the flash extraction process, thereby giving the extract (i.e. instant coffee powder) excellent flavor.

[0019] In summary, the utility model has the characteristics of simple structure, good extract quality, short extraction time and high powder yield. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of a partial connection structure of the utility model;

[0021] In the figure: 1-feeding unit, 11-raw material bin, 12-screw metering machine, 13-electric valve, 2-water supply unit, 21-water tank, 22-high pressure frequency conversion pump, 23-flow meter, 24-heater, 3-screw conveyor, 4-extraction unit, 41-first-stage flash extraction tank, 411-liquid storage chamber, 42-second-stage flash extraction tank, 43-secondary pump, 44-filter screen, 45-spiral guide plate, 46-coffee grounds straight pipe, 47-liquid outlet pump, 5-cooler, 6-storage tank, 7-extruder, 8-recovery liquid pump, 9-fine filter. DETAILED DESCRIPTION

[0022] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but the present invention is not limited in any way. Any changes or improvements made based on the teachings of the present invention belong to the protection scope of the present invention.

[0023] like Figure 1 As shown, the utility model includes a feeding unit 1, a water supply unit 2, a screw conveyor 3, an extraction unit 4, a cooler 5, a storage tank 6, and a control system. The discharge port I of the feeding unit 1 and the water outlet of the water supply unit 2 are respectively connected to the feed port II of the screw conveyor 3. The extraction unit 4 includes a primary flash extraction tank 41, a secondary flash extraction tank 42, and a secondary pump 43. The discharge port II of the screw conveyor 3 is connected to the feed port III of the primary flash extraction tank 41. The discharge port III of the primary flash extraction tank 41 is connected to the feed port IV of the secondary flash extraction tank 42 through the secondary pump 43. A filter screen 44 is provided in the secondary flash extraction tank 42. The filtrate outlet of the secondary flash extraction tank 42 is connected to the water inlet of the cooler 5. The water outlet of the cooler 5 is connected to the storage tank 6. The feeding unit 1, the water supply unit 2, the screw conveyor 3 and the secondary pump 43 are respectively electrically connected to the control system.

[0024] The primary flash extraction tank 41 and the secondary flash extraction tank 42 are both cylindrical closed percolation tanks, and a spiral guide plate 45 is fixedly arranged in the inner cavity of the percolation tank from top to bottom. The discharge port II of the screw conveyor 3 is connected with the feed port III at the top of the primary flash extraction tank 41, and the discharge port III at the bottom of the primary flash extraction tank 41 is connected with the feed port IV at the top of the secondary flash extraction tank 42 through the secondary pump 43.

[0025] An inverted cone-shaped liquid storage chamber 411 is further provided at the bottom of the primary flash extraction tank 41 , and a discharge port III of the primary flash extraction tank 41 is provided at the bottom of the liquid storage chamber 411 .

[0026] The filter screen 44 is an inverted cone-shaped filter screen and is arranged at the lower part of the secondary flash extraction tank 42 . The open end of the filter screen 44 is tightly connected to the inner wall of the secondary flash extraction tank 42 . The filtrate outlet is arranged outside the filter screen 44 at the bottom of the secondary flash extraction tank 42 .

[0027] An extruder 7 is provided below the secondary flash extraction tank 42, and a coffee grounds straight pipe 46 is provided at the lower end of the filter screen 44 in the secondary flash extraction tank 42. The top end of the coffee grounds straight pipe 46 is connected to the bottom of the filter screen 44, and the lower part of the coffee grounds straight pipe 46 passes through the bottom wall of the secondary flash extraction tank 42 and is connected to the feed port V of the extruder 7. The liquid outlet I of the extruder 7 is connected to the water inlet of the cooler 5 through the recovery liquid pump 8, and the extruder 7 and the recovery liquid pump 8 are electrically connected to the control system respectively.

[0028] A fine filter 9 is also provided between the secondary flash extraction tank 42 and the cooler 5. The filtrate outlet of the secondary flash extraction tank 42 is connected to the liquid inlet of the fine filter 9 through a liquid outlet pump 47. The liquid outlet I of the extruder 7 is connected to the liquid inlet of the fine filter 9 through a recovery liquid pump 8. The liquid outlet II of the fine filter 9 is connected to the water inlet of the cooler 5. The liquid outlet pump 47 is electrically connected to the control system.

[0029] The feeding unit 1 includes a raw material bin 11 and a screw metering machine 12. The raw material bin 11 is fixedly arranged above the screw metering machine 12. The screw metering machine 12 is arranged above the screw conveyor 3. The discharge port IV of the raw material bin 11 is connected with the feed port VI of the screw metering machine 12. The discharge port VI of the screw metering machine 12 is connected with the feed port II of the screw conveyor 3 through a pipeline. The screw metering machine 12 is electrically connected to the control system.

[0030] An electric valve 13 is also provided on the pipeline connecting the discharge port VI of the screw metering machine 12 and the feed port II of the screw conveyor 3 , and the electric valve 13 is electrically connected to the control system.

[0031] The water supply unit 2 includes a water tank 21, a high-pressure variable frequency pump 22, a flow meter 23, and a heater 24 which are connected in sequence. The high-pressure variable frequency pump 22, the flow meter 23, and the heater 24 are electrically connected to the control system respectively.

[0032] The control system is an industrial computer or a PLC system, and the extruder 7 is a commercially available food extruder.

[0033] like Figure 1 As shown, the coffee flash extraction principle and process of the utility model are as follows:

[0034] Step 1: Crush the roasted coffee beans into fine powder with a particle size of about 60 mesh, and then put it into the raw material bin 11.

[0035] Step 2: Input the feed rate of coffee powder, such as 0.1T / h, extraction water flow rate, such as 1.5T / h, and water temperature, such as 100°C, into the control system, start the automatic control switch of the control system, and the device enters the automatic operation state.

[0036] Step 3: The high-pressure variable frequency pump 22 automatically adjusts the operating pressure according to the set water supply flow rate, such as 1.5 T / h (with an overpressure protection device, the same below), and the heater 24 heats the water supply at the set temperature, such as 100°C, to deliver hot water to the screw conveyor 3. The screw metering machine 12 continuously feeds the roasted coffee bean powder into the feed port II of the screw conveyor 3 at the set feed rate, such as 0.1 T / h, and the coffee powder and hot water are infiltrated in the screw conveyor 3.

[0037] Step 4: The control system controls the rotation speed of the screw conveyor 3 according to a preset value, and finally sprays the solid-liquid mixture into the first-stage flash extraction tank 41 under high pressure for primary extraction. The spiral guide plate 45 provided in the first-stage flash extraction tank 41 causes the fine coffee powder to tumble in the extraction liquid, thereby improving the extraction rate and the powder yield.

[0038] Step 5: After the primary extraction of the coffee powder, the solid-liquid mixture flows out from the bottom of the primary flash extraction tank 41, and is pressurized by the secondary pump 43 and sprayed into the secondary flash extraction tank 42. Similarly, the spiral guide plate 45 in the tank causes the coffee powder to roll in the extraction liquid, thereby fully extracting the coffee powder.

[0039] Step 6: After the extract passes through the filter screen 44 at the bottom of the secondary flash extraction tank 42, it flows out from the filtrate outlet and is pressurized and transported to the fine filter 9 through the outlet pump 47 for filtration. Finally, the liquid is cooled to a set temperature such as 10°C by the cooler 5, and then enters the storage tank 6 for storage. At the same time, the coffee grounds directly enter the extruder 7 through the coffee grounds straight pipe 46 at the bottom of the secondary flash extraction tank 42. The extruded coffee grounds are discharged from the slag discharge port of the extruder 7 for solid waste treatment. The extruded liquid is transported to the front end of the fine filter 9 through the outlet port I through the recovery liquid pump 8 and mixed with the extract pumped out by the outlet pump 47, and finally passed into the fine filter 9.

[0040] Step 7: In order to reduce the amount of extraction liquid flowing into the extruder 7, coffee grounds must be stored in the coffee grounds straight pipe 46 connected to the feed port V of the extruder 7. Therefore, when the extraction liquid passes through the filter screen 44 of the secondary flash extraction tank 42, the extruder 7 will automatically adjust the frequency of the extrusion motor according to the height of the coffee grounds in the coffee grounds straight pipe 46, thereby adjusting the rotation speed of the extruder 7 in time to ensure that the coffee grounds in the coffee grounds straight pipe 46 have a necessary height of coffee grounds.

[0041] The above is only a preferred specific implementation of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A continuous automatic device capable of improving the quality of coffee flash extraction, characterized in that: The invention comprises a feeding unit (1), a water supply unit (2), a screw conveyor (3), an extraction unit (4), a cooler (5), a storage tank (6), and a control system. The discharge port I of the feeding unit (1) and the water outlet of the water supply unit (2) are respectively connected to the feed port II of the screw conveyor (3). The extraction unit (4) comprises a primary flash extraction tank (41), a secondary flash extraction tank (42), and a secondary pump (43). The discharge port II of the screw conveyor (3) and the feed port II of the primary flash extraction tank (41) are connected to the feed port II of the primary flash extraction tank (41). Ⅲ, the discharge port Ⅲ of the primary flash extraction tank (41) is connected to the feed port Ⅳ of the secondary flash extraction tank (42) through the secondary pump (43), a filter screen (44) is arranged in the secondary flash extraction tank (42), the filtrate outlet of the secondary flash extraction tank (42) is connected to the water inlet of the cooler (5), the water outlet of the cooler (5) is connected to the storage tank (6), and the feed unit (1), the water supply unit (2), the screw conveyor (3) and the secondary pump (43) are respectively electrically connected to the control system.

2. The continuous automatic device capable of improving the quality of coffee flash extraction according to claim 1, characterized in that: The first-stage flash extraction tank (41) and the second-stage flash extraction tank (42) are both cylindrical closed percolation tanks. A spiral guide plate (45) is fixedly arranged from top to bottom in the inner cavity of the percolation tank. The discharge port II of the screw conveyor (3) is connected to the feed port III at the top of the first-stage flash extraction tank (41). The discharge port III at the bottom of the first-stage flash extraction tank (41) is connected to the feed port IV at the top of the second-stage flash extraction tank (42) via a second-stage pump (43).

3. The continuous automatic device capable of improving the quality of coffee flash extraction according to claim 2, characterized in that: An inverted cone-shaped liquid storage chamber (411) is further provided at the bottom of the primary flash extraction tank (41), and a discharge port III of the primary flash extraction tank (41) is provided at the bottom of the liquid storage chamber (411).

4. The continuous automatic device capable of improving the quality of coffee flash extraction according to claim 2, characterized in that: The filter screen (44) is an inverted cone-shaped filter screen and is arranged at the lower part of the secondary flash extraction tank (42); the open end of the filter screen (44) is tightly connected to the inner wall of the secondary flash extraction tank (42); and the filtrate outlet is arranged outside the filter screen (44) at the bottom of the secondary flash extraction tank (42).

5. The continuous automatic device capable of improving the quality of coffee flash extraction according to claim 4, characterized in that: An extruder (7) is arranged below the secondary flash extraction tank (42); a coffee grounds straight tube (46) is arranged at the lower end of the filter screen (44) in the secondary flash extraction tank (42); the top end of the coffee grounds straight tube (46) is connected to the bottom of the filter screen (44); the lower part of the coffee grounds straight tube (46) passes through the bottom wall of the secondary flash extraction tank (42) and is connected to the feed port V of the extruder (7); the liquid outlet I of the extruder (7) is connected to the water inlet of the cooler (5) via a recovery liquid pump (8); and the extruder (7) and the recovery liquid pump (8) are respectively electrically connected to a control system.

6. The continuous automatic device capable of improving the quality of coffee flash extraction according to claim 5, characterized in that: A fine filter (9) is also provided between the secondary flash extraction tank (42) and the cooler (5); the filtrate outlet of the secondary flash extraction tank (42) is connected to the liquid inlet of the fine filter (9) via a liquid outlet pump (47); the liquid outlet I of the extruder (7) is connected to the liquid inlet of the fine filter (9) via a recovery liquid pump (8); the liquid outlet II of the fine filter (9) is connected to the water inlet of the cooler (5); and the liquid outlet pump (47) is electrically connected to a control system.

7. The continuous automatic device capable of improving the quality of coffee flash extraction according to any one of claims 1 to 6, characterized in that: The feeding unit (1) comprises a raw material bin (11) and a screw metering machine (12); the raw material bin (11) is fixedly arranged above the screw metering machine (12); the screw metering machine (12) is arranged above the screw conveyor (3); the discharge port IV of the raw material bin (11) is connected to the feed port VI of the screw metering machine (12); the discharge port VI of the screw metering machine (12) is connected to the feed port II of the screw conveyor (3) through a pipeline; and the screw metering machine (12) is electrically connected to a control system.

8. The continuous automatic device capable of improving the quality of coffee flash extraction according to claim 7, characterized in that: An electric valve (13) is also provided on the pipeline connecting the discharge port VI of the screw metering machine (12) and the feed port II of the screw conveyor (3), and the electric valve (13) is electrically connected to the control system.

9. The continuous automatic device capable of improving the quality of coffee flash extraction according to claim 7, characterized in that: The water supply unit (2) comprises a water tank (21), a high-pressure variable frequency pump (22), a flow meter (23), and a heater (24) which are connected in sequence; the high-pressure variable frequency pump (22), the flow meter (23), and the heater (24) are respectively electrically connected to a control system.

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