SYSTEM AND METHOD FOR PRODUCING AN EXTRACT

Abstract

A system and method for producing an extract from an extraction material by means of an extraction agent comprises a supply line for the extraction agent, a heating device, a brewing device for the extraction material and an extract collection container. The supply line contains a measuring element and at least one volumetric flow control element for the volumetric flow of the extraction agent. In addition, the temperature of the heated extraction agent can be measured by means of the measuring element. The system comprises a control unit, the control unit containing a dosage regime for the heated extraction agent for the brewing device. The dosage regimen can be selected by means of an input device, whereby the volumetric flow control element can be set according to the dosage regimen and is monitored via the measuring element.

Claims

1. A system for producing an extract of a hot beverage from an extraction material by means of an extraction agent, comprising a supply line for a continuous supply of the extraction agent, a heating device, a brewing device, as well as an extract collection container, wherein the brewing device contains the extraction material, wherein the supply line is configured for supplying the extraction agent to the heating device, wherein a connection line is provided for the heated extraction agent from the heating device to the brewing device, wherein the brewing device contains a receiving element for the extraction material, which is permeable to the heated extraction agent, so that the extract is obtainable by contact of the heated extraction agent with the extraction material, wherein the extract collection container is configured to collect the extract, wherein the supply line or the connection line contain at least one measuring element and at least one volumetric flow control element, wherein a control unit is provided which contains at least one dosage regimen for the heated extraction agent for the brewing device, the dosage regimen being selectable by means of an input device, whereby the volumetric flow control element can be set according to the dosage regimen and is monitored via the measuring element, and wherein a heating controller for controlling a heat supply to the heating device is provided.

2. The system of claim 1, wherein an opening time of the volumetric flow control element can be determined by means of the control unit from a desired volumetric flow or the pressure.

3. The system of claim 1, wherein the control unit comprises a computing unit, a comparison unit and a memory unit, wherein the memory unit contains the dosage regimen, or a plurality of dosage regimens.

4. (canceled)

5. The system of claim 3, wherein the dosage regimen contains desired volumetric flows, desired pressures or desired temperatures of the extraction agent or the heated extraction agent for a production of the extract.

6. The system of claim 5, wherein a measured volumetric flow value can be compared with a desired volumetric flow by means of the comparison unit or wherein a measured pressure value can be compared with the desired pressure by means of the comparison unit or wherein a measured temperature value can be compared with the desired temperature by means of the comparison unit or wherein an extraction process for a desired volumetric flow can be extrapolated from extraction processes with known volumetric flows.

7-9. (canceled)

10. The system of claim 3, wherein the desired volumetric flow can be added as a disturbance variable.

11. The system of claim 1, wherein the measuring element is configured as a flow measuring device for determining a measured volumetric flow value or a pressure measuring device for determining a measured pressure value or a temperature measuring device for determining a measured temperature value of at least one of the extraction agent or of the heated extraction agent.

12. The system of claim 1, wherein the volumetric flow control element is configured as a two-way valve, a control valve, a multi-way valve or a pump, or wherein the supply line contains the control valve or the pump or wherein the connection line contains the multi-way valve.

13. (canceled)

14. (canceled)

15. The system of claim 12, wherein the pump is configured as a controllable pump.

16. (canceled)

17. The system of claim 1, wherein the brewing device comprises a pressure vessel.

18. The system of claim 1, further comprising a distribution element for distributing the extraction agent onto the extraction material.

19. A method for producing an extract of a hot beverage from an extraction material by means of an extraction agent, comprising a system containing a supply line for the extraction agent, a heating device, a brewing device, and an extract collection container, wherein the brewing device contains the extraction material, wherein the extraction agent is fed to the heating device via the supply line, wherein the extraction agent is heated in the heating device to form a heated extraction agent, wherein the heated extraction agent is conducted from the heating device to the brewing device by means of a connection line, wherein an extract is obtained by contact of the heated extraction agent with the extraction material which contains the extraction agent and soluble components of the extraction material, wherein the extract is collected in the extract collection container, wherein the supply line or the connection line contain a measuring element and a volumetric flow control element, wherein a control unit is provided which contains at least one dosage regimen for the heated extraction agent for the brewing device, the dosage regimen is selected by means of an input device, wherein the volumetric flow control element is set according to the dosage regimen and is monitored via the measuring element wherein a heating controller controls a heat supply to the heating device.

20. The method of claim 19, wherein the volumetric flow of the extraction agent, which is converted by the heating device into the heated extraction agent, is recorded by means of a flow measuring device.

21. The method of claim 19, wherein a pressure of the extraction agent is measured by means of a pressure measuring device.

22. The method of claim 19, wherein the volumetric flow control element contains at least one flow control element selected from the group consisting of a control valve, a switching valve, a pump or a multi-way valve, wherein the control valve or the multi-way valve can be set in such a way that a desired volumetric flow corresponds to a measured volumetric flow value or a desired pressure corresponds to a measured pressure value or a desired temperature corresponds to a measured temperature value.

23. The method of claim 22, wherein the control unit comprises a computing unit, a comparison unit, a memory unit wherein the memory unit contains a plurality of dosage regimens which contain the desired volumetric flows, pressures, and the desired temperatures of the extraction agent or the heated extraction agent for production of the extract, wherein the volumetric flow measurement value is compared with the desired volumetric flow or the pressure measurement value with the desired pressure or the temperature measurement value with the desired temperature by means of the comparison unit or wherein an extraction process for a desired volumetric flow is extrapolated from extraction processes with known volumetric flows.

24. (canceled)

25. The method of claim 22, wherein one of the dosage regimens is selected by means of the input device which comprises the desired volumetric flow or the desired pressure or the desired temperature of the heated extraction agent.

26. The method of claim 22, wherein the measured volumetric flow value is compared with the desired volumetric flow, or the measured pressure value is compared with the desired pressure, or the measured temperature value is compared with the desired temperature by means of the control unit.

27. (canceled)

28. (canceled)

29. The method of claim 19, wherein a pressure of the heated extraction agent is increased in the brewing device.

30. The method of claim 19, wherein at least part of the extraction agent is not passed through the heating device, wherein at least a portion of the extraction agent can be fed into a bypass line by actuating a switching valve, so that the extraction agent is led to the brewing device or to the extract collection container bypassing the heating device.

31. (canceled)

32. (canceled)

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The system according to the invention is illustrated below with the aid of a few exemplary embodiments. It is shown in

[0058] FIG. 1 a system according to a first embodiment,

[0059] FIG. 2 a system according to a second embodiment,

[0060] FIG. 3 a system according to a third embodiment,

[0061] FIG. 4 a first example of a dosage regimen,

[0062] FIG. 5 a second example of a dosage regimen,

[0063] FIG. 6 a system according to a fourth embodiment,

[0064] FIG. 7 a third example of a dosage regimen,

[0065] FIG. 8 a fourth example of a dosage regimen.

DETAILED DESCRIPTION OF THE DRAWINGS

[0066] FIG. 1 shows a system 20 for producing an extract 10 from an extraction material 8 by means of an extraction agent 9, comprising a supply line 14 for the extraction agent 9, a heating device 5, a brewing device 6, and an extract collection container 11. If the system is to be used to produce a hot beverage, the extraction agent 9 can be water. The supply line 14 is connected to a water connection 1 for this application. The water connection 1 can be designed as a reservoir, tank or as a water pipe. The water connection 1 can optionally contain a water treatment system, for example a decalcifying system. The pressure of the extraction agent 9 in this range is in the range of between one and two bar; the pressure can essentially correspond to the pressure that is provided in the water pipe.

[0067] The supply line 14 is configured to supply the extraction agent 9 to the heating device 5. According to the present embodiment, the heating device 5 contains heating elements 15 for heating the extraction agent 9. A temperature measuring device 12 can be provided to determine the temperature prevailing in the heating device 5. The temperature measuring device 12 can comprise a temperature sensor or temperature capturing device.

[0068] A connection line 17 is provided for conducting the heated extraction agent 19 from the heating device 5 to the brewing device 6. A temperature measuring device 13 can be arranged in the connection line 17, preferably directly at the connection thereof to the heating device 5.

[0069] The brewing device 6 contains the extraction material 8. The brewing device 6 contains a receiving element 16 for the extraction material 8, which is permeable to the heated extraction agent 19, so that the extract 10 can be obtained by contact of the heated extraction agent 19 with the extraction material 8. The extract collection container 11 is configured to collect the extract 10. The extract collection container 11 can in particular comprise a cup for receiving a hot beverage.

[0070] A flow measuring device 18 for determining a measured value for the volumetric flow of the extraction agent 9 is arranged in the supply line 14. The flow measuring device 18 can be arranged at any desired position upstream of the heating device 5. The supply line 14 contains a control valve 7. The volumetric flow of the extraction agent 9 can be changed by means of the control valve 7. The control valve 7 can in particular be configured as a proportional valve. The flow measuring device 18 can be arranged downstream or upstream of the control valve 7. The control valve 7 can also be used for metering the extraction agent 9 and can be closed again after the corresponding opening time for the addition of a predetermined volume thereof has elapsed. The opening time is understood here to be a time duration or period in which the control valve 7 is at least partially open, so that the extraction agent 9 can flow to the heating device 5.

[0071] The system 20 contains a control unit 2, by means of which the volumetric flow of the extraction agent 9, as well as the temperature of the heated extraction agent 19 and the heat supply to the heating device 5 can be controlled. The control unit 2 comprises a computing unit 21, a comparison unit 22 and a memory unit 23. The memory unit 23 contains a plurality of dosage regimens which contain the desired volumetric flows and the desired temperatures of the extraction agent 9 for the production of the extract 10.

[0072] One of the dosage regimens can be selected by means of an input device 24, which includes the desired volumetric flow and the desired temperature of the heated extraction agent 19. By means of the computing unit 21, the opening time of the control valve 7 can be determined from the desired volumetric flow. By means of the comparison unit 22, the measured volumetric flow value can be compared with the desired volumetric flow, so that the control valve 7 can be set in such a way that the desired volumetric flow matches the measured volumetric flow value.

[0073] The extraction material 8 can be arranged in or on a receiving element 16, which can be configured as a filter, bag, or pad to be used for preparing a hot beverage.

[0074] The system can comprise a distribution element 26 for distributing the extraction agent 9 onto the extraction material 8. The distribution element 26 can, for example, be configured as a shower head. By means of the distribution element 26, the heated extraction agent 9 can be evenly distributed over the extraction material 8. If the distribution element is designed as a filter, for example a paper filter, for an extraction material to provide a hot beverage, different turbulences arise in the filter at different flow rates, which can result in different flavorings of the extract.

[0075] FIG. 2 shows a system according to a second embodiment, whereby the same reference numerals are used as in FIG. 1 for units, components or elements that are the same or have the same effect. In the following, only the differences with respect to the first embodiment according to FIG. 1 are described, otherwise, reference is made at this point to the description of FIG. 1, which should also apply to the same or identically acting units, components, or elements of this embodiment.

[0076] The system 20 according to FIG. 2 differs from the system 20 according to FIG. 1 in that it comprises a switching valve 4. The switching valve 4 is arranged in the supply line 14 between the control valve 7 and the heating device 5. As in the present illustration, it can be arranged between the flow measuring device 18 and the heating device 5; according to an embodiment not shown, it could also be arranged between the control valve 7 and the flow measuring device 18. The switching valve 4 is configured, for example, as a multi-way valve. In a first position of the switching valve 4, the connection between the control valve 7 and the heating device 5 is open, so that the extraction agent 9 can flow into the heating device 5. In a second position of the switching valve 4, the connection between the control valve 7 and the heating device 5 is closed and instead a connection between the control valve 7 and the extract collection container 11 is opened. This connection is shown as a bypass line 25.

[0077] Thus, according to this embodiment, at least a portion of the extraction agent 19 is not passed through the heating device 5. In particular, by actuating the switching valve 4, at least a portion of the extraction agent 9 is fed into a bypass line 25, so that the extraction agent 9 is conducted past the heating device 5 to the extract collection container 11.

[0078] FIG. 3 shows a system 20 according to a third embodiment, whereby the same reference numerals as in FIG. 1 are used for units, components or elements that are the same or have the same effect. In the following, only the differences to the first embodiment according to FIG. 1 are described, otherwise, reference is made at this point to the description of FIG. 1, which should also apply to the same or identically acting units, components, or elements of this embodiment.

[0079] According to FIG. 3, the brewing device 6 comprises a pressure vessel 36. The extraction material 8 is arranged in the interior of this pressure vessel 36 and is shown schematically. A pressure-increasing means for the extraction agent 9, for example a pump, can be provided in the supply line 14. The supply line 14, the heating device 5, the connection line 17 and the brewing device 6 form a closed system so that, apart from line losses, no pressure losses occur in the system and the pressure of the heated extraction agent 19 essentially corresponds to the pressure applied by means of the pressure-increasing means. The extraction material 8 can be arranged in or on a receiving element 16, which can be configured as a portafilter, capsule, bag, or pad for use in preparing a hot beverage. For the preparation of a hot beverage, the pressure is usually in a pressure range from 6 to 10 bar.

[0080] According to each of the embodiments, the extraction agent 9 can also be metered by means of the control valve 7. For this purpose, the control valve 7 can be controlled by the control unit 2 in such a way that the control valve 7 is closed when the measured value of the volumetric flow corresponds to the portion of the heated extraction agent 19 required in a certain phase of the extraction process that is to be supplied to the brewing device 6. A dosage regimen for metering the extraction agent 9 can comprise a single phase or a plurality of phases.

[0081] FIG. 4 shows a diagram for a dosage regimen according to which the extraction agent 9 is heated in a single phase. The diagram contains a time axis as the abscissa, on which the time t is plotted in seconds (s). The ordinate contains two different quantities, on the one hand the volumetric flow (ml/s) and on the other hand the temperature (° C.). The volumetric flow is shown with a continuous line, the temperature with a dash-dotted line, in order to be able to differentiate the two quantities more easily from one another. The volumetric flow is constant according to this dosage regimen. This means that the control valve 7 is opened at time t0, the opening width is kept constant and is closed again at time t1. The difference t1−t0 corresponds to the opening time of the control valve 7. The area of the volumetric flow shown as a rectangle corresponds to the metered volume D of the extraction agent 9. The point in time t0 is dimensioned such that the heating device 5 can be heated to the heating temperature T1 before the control valve 7 is opened. As soon as the heating device 5 has reached the heating temperature T1, that is to say at time t0 in the present illustration, the control valve 7 is opened. The heating temperature T1 remains constant until time t1. If the control valve is closed again at time t1, the heating temperature T1 drops because the heating device cools down. A further supply of energy to the heating device 5 is no longer necessary, so that no additional energy is required in the standby state.

[0082] FIG. 5 shows an exemplary example of a dosage regimen according to which the extraction agent 9 is heated in several phases. In a first phase, which takes place in a time segment that lasts from a point in time t0 to t1, the first volume D1 of the extraction agent 9 can be heated to a temperature T1. A heating phase is provided before time t0, in which the heating device 5 is preheated to the temperature required to obtain the temperature T1. If a flow heater is used as the heating device, the temperature of the heating device 5 for the flow heater, which is detected by the temperature measuring device 12, essentially corresponds to the temperature T1 of the heated extraction agent 19, which is measured by the temperature measuring device 13.

[0083] In a second phase, which runs in a time segment that lasts from a point in time t1 to t2, the control valve 7 is closed, so that no extraction agent 9 is passed to the heating device 5. The supply of heat to the heating device 5 is also interrupted, so that a cooling to temperature T2 takes place in the second phase. The heated extraction agent 19 is passed to the brewing device 6 during the second phase and comes into contact with the extract 10. If the extract 10 is in the form of a powder or a solid containing pores, the heated extraction agent 19 fills the pores in the second phase which persist between the grains of the powder or that persist in the solid. The extract 10 is moistened by the heated extraction agent 19 in this second phase.

[0084] In a third phase, which runs in a time segment that lasts from a point in time t2 to t3, the control valve 7 is opened again so that a second volume D2 of the extraction agent 9 can be heated to a temperature T2. According to the present example, the temperature T2 differs from the temperature T1. According to this example, the temperature T2 is lower than the temperature T1. According to an embodiment not shown, the temperature T2 could also be higher than the temperature T1. In the third phase, the volumetric flow is also smaller than in the first phase. The heat requirement for the heating device 5 is adapted accordingly. In the present example, the opening time t3−t2 essentially corresponds to the opening time t1−t0; these opening times can also differ from one another. The closing time t2−t1 between the opening times can correspond to at least one of the opening times or can differ from the opening times.

[0085] In the fourth phase, which runs in a time segment that lasts from a point in time t3 to t4, the control valve 7 is closed so that no extraction agent 9 is passed to the heating device 5. In this example, the closing time t4−t3 is shorter than the previous opening time t3−t2. During this brief period of time, the temperature can remain essentially constant, that is to say it can continue to be at the temperature T2.

[0086] In a fifth phase, which runs in a time segment that lasts from a point in time t4 to t5, the control valve 7 is opened again, so that a third volume D3 of the extraction agent 9 can be heated to a temperature T2, which during the opening time to a temperature T3 is lowered. According to the present example, the heating thus takes place with a negative temperature gradient. The heated extraction agent 19 has the temperature T2 at time t4. At time t5, the heated extraction agent 19 has the temperature T3. The temperature profile is linear in the present example, but it could also have a non-linear profile. According to an embodiment not shown, the temperature T3 could also be higher than the temperature T2. In the fifth phase, the volumetric flow is also greater than in the third phase. The heat requirement for the heating device 5 is adapted accordingly. In the present example, the opening time t5−t4 is longer than the opening time t1−t0.

[0087] In the sixth phase, which follows on from the fifth phase and which expires in a time segment that lasts from time t5 to t6, the control valve 7 is closed so that no extraction agent 9 is passed to the heating device 5. In this example, the closing time t6−t5 is shorter than the previous opening time t5−t4. During this brief period of time, the temperature is increased since a higher temperature is required for the subsequent seventh phase.

[0088] In a seventh phase, which runs in a time segment that lasts from a point in time t6 to t7, the control valve 7 is opened again so that a fourth volume D4 of the extraction agent 9 can be heated to a temperature T4 up to a temperature T5. The temperature is thus increased from the temperature T4 to the temperature T5 during the opening time t7−t6. According to the present example, the heating thus takes place with a positive temperature gradient. The heated extraction agent 19 has the temperature T4 at time t6. At the point in time t7, the heated extraction agent 19 has the temperature T5. The temperature profile is linear in the present example, but it could also have a non-linear profile. In the seventh phase, the volumetric flow is also changed. The heat requirement for the heating device 5 is adapted accordingly. According to the present example, the volumetric flow decreases from time t6 to time t7. For this purpose, the opening cross section of the control valve 7 is continuously or gradually reduced.

[0089] FIGS. 4 and 5 show only by way of example two examples for a large number of possible dosage regimens. Each of the dosage regimens can be stored in the memory unit 23 in order to be carried out when required by the instruction of a user.

[0090] FIG. 6 shows a system 50 according to a fourth embodiment, whereby the same reference numerals are used as in FIG. 1 for units, components or elements that are the same or have the same effect. In the following, only the differences from the first embodiment according to FIG. 1 are described, otherwise, reference is made at this point to the description of FIG. 1, which should also apply to the same or identically acting units, components, or elements of this embodiment.

[0091] According to FIG. 6, the brewing device 6 comprises a pressure vessel 36. The extraction material 8 is arranged in the interior of this pressure vessel 36 and is therefore shown schematically. A pressure-increasing means for the extraction agent 9, for example a pump 40, is provided in the supply line 14. The supply line 14, the heating device 5, the connection line 17 and the brewing device 6 form a closed system so that, apart from line losses, no pressure losses occur in the system and the pressure of the heated extraction agent 19 essentially corresponds to the pressure applied by means of the pressure-increasing means. The extraction material 8 can be arranged in or on a receiving element 16, which can be designed as a portafilter, capsule, bag, or pad for use in preparing a hot beverage. For the preparation of a hot beverage, the pressure is usually in a pressure range from 5 to 20 bar.

[0092] According to the present embodiment, a pressure sensor 41 is provided in the supply line 14 between the pump 40 and the heating device 5. The pressure generated by the pump 40 can be measured by means of the pressure sensor 41. The measured pressure value determined by the pressure sensor 41 is transmitted to the control unit 2. In addition, the pump can contain an angular velocity sensor or a flow measuring device, by means of which the volumetric flow flowing through the pump or the throughput can be determined. The corresponding measured value for the angular velocity, the volumetric flow or the throughput can also be transmitted to the control unit 2. According to this embodiment, the flow measuring device 18 is thus located directly on the pump 40 and not upstream of the pump 40, as shown in FIG. 6 as a possible variant. Of course, the flow measuring device 18 can also be located upstream of the pump 40.

[0093] Optionally, the extraction agent 9 can be metered by means of a control valve 7 in a manner analogous to the variants shown in FIGS. 1 to 3. For this purpose, the control valve 7 can be controlled by the control unit 2 in such a way that the control valve 7 is closed when the measured value of the volumetric flow corresponds to the portion of the heated extraction agent 19 required in a certain phase of the extraction process that is to be supplied to the brewing device 6. A dosage regimen for metering the extraction agent 9 can comprise a single phase or a plurality of phases. The control valve can in particular be configured as a proportional valve.

[0094] The use of a pressure-increasing means for the extraction agent 9 in the supply line 14 enables the generation of a flow profile or a plurality of flow profiles which are superimposed by minimum pressure profiles or maximum pressure profiles. That is, by setting the pump 41 or the control valve 7, different pressures or volumetric flows can be set accordingly. The pressures or volumetric flows can be changed during the duration of an extraction process, which is to say the extraction process can comprise several phases, each of the phases being able to be characterized by a different pressure or volumetric flow.

[0095] This means that the volume flow or the pressure in the supply line 14 downstream of the pressure-increasing means can be changed during the duration of an extraction process. As a result, the volumetric flow or pressure in the connection line 17 can also be changed.

[0096] Optionally, a multi-way valve 42 can be arranged in the connection line 17. The multi-way valve 42 is located between the heating device 5 and the brewing device 6. According to the present embodiment, the multi-way valve 42 has three different combinations of fluid connections, it is thus configured as a three-way valve. According to this embodiment, the multi-way valve 42 has three different positions and three fluid lines. One of these fluid lines is the connection line 17 through which heated extraction agent 19 can be supplied to the multi-way valve 42. Another, second fluid line is the connection line 43, through which the heated extraction agent 19 can be fed to the brewing device 6. A third fluid line can be provided, which is configured as a wastewater line 44 in order to supply the heated extraction agent 19 to a wastewater container or sewer.

[0097] In the first position of the multi-way valve 42, the connection line 17 is connected to the connection line 43 for carrying out an extraction process. The connection to the wastewater line 44 is interrupted in the first position, so that the wastewater line 44 does not receive any heated extraction agent 19. In the second position of the multi-way valve 42, the connection line 17 is connected to the sewage line 44. The connection to the connection line 43 is interrupted in the second position, so that the connection line 43 is not supplied with any heated extraction agent 19. In the second position, the connection line 17 and the supply line 14 can be flushed. This can be advantageous in order to preheat the connection line 17 and the multi-way valve 42 with heated extraction agent 19 in order to set the temperature precisely for a subsequent extraction. Therefore, optimal temperature conditions for the extraction can be obtained. In particular, any temperature profiles can be set exactly, in particular by means of the control unit 2.

[0098] In the third position of the multi-way valve 42, a connection between the connection line 43 and the sewage line 44 can be established. The connection to the connection line 17 is interrupted in the third position. A pressure in the pressure vessel 36 that is still higher than that of the surroundings can be reduced particularly at the end of an extraction.

[0099] The multi-way valve 42 can comprise two or three of the positions described, that is, a two-way valve can alternatively be provided instead of the three-way valve shown.

[0100] The brewing device 6 contains the extraction material 8. The brewing device 6 contains a receiving element 16 for the extraction material 8, which is permeable to the heated extraction agent 19, so that the extract 10 can be obtained by contact of the heated extraction agent 19 with the extraction material 8. The extract 10 leaves the brewing device via the discharge 47 in order to fill an extract collection container 11 at least partially. The extract collection container 11 is configured to collect the extract 10. The extract collection container 11 can in particular comprise a cup for receiving a hot beverage.

[0101] The pressure prevailing in the connection line 43 can be measured by means of a pressure measuring device 45. The measured pressure value can be transmitted to the control unit 2. The pressure measurement value determined with the pressure measuring device 45 can be used by means of the computing unit 21 located in the control unit 2 and the comparison unit 22 to superimpose the pressure profile which characterizes the extraction process.

[0102] The extraction process can thus be controlled as required by means of the control unit, because different flow rates, pressures, temperatures and pauses between individual phases of brewing or extraction can be set.

[0103] According to the present embodiment, the connection line 17, the multi-way valve 42, the connection line 43, the brewing device 6, the valve 46 and the discharge 47 can be preheated by means of heated extraction agent if there is no extraction material 8 in the brewing device. Thus, during the actual extraction process, there is no or only insignificant cooling of the heated extraction agent until it reaches the extraction material 8. Therefore, the temperature of the heated extraction agent can be precisely adjusted, so that an improved temperature stability can be obtained during the extraction process.

[0104] According to each of the embodiments, the extraction material 8 can be extracted with a pressure that is essentially the same for the entire extraction material 8, thus, a more uniform extraction can be performed with improved mass transfer from the extraction material 8 into the heated extraction agent 19, so that the concentration of the soluble components of the extraction material in the extract 10 is increased.

[0105] FIG. 7 shows a diagram for a dosage regimen according to which the extraction agent 9 is fed to the brewing device 6 according to FIG. 6 with a single predetermined pressure. The temperature profile should correspond to the temperature profile shown in FIG. 4. The diagram contains a time axis as the abscissa, on which the time t is plotted in seconds (s). The ordinate contains two different quantities, on the one hand the volumetric flow (ml/s) and on the other hand the pressure (bar). The volumetric flow is shown with a continuous line, the pressure with a dashed line, in order to be able to differentiate the two quantities more easily from one another. The volumetric flow is constant according to this dosage regimen, that is, the pump 40 delivers a constant volumetric flow. This means that the pump generates an increasing volumetric flow up to time t0, then the volumetric flow is kept constant by the pump and generates a decreasing volumetric flow at time t1. The difference t1−t0 corresponds to the duration of the brewing process. The area of the volumetric flow shown as a rectangle corresponds to the volume D of the extraction agent 9 during the brewing process.

[0106] The flow measuring device 18 can be used to determine whether the pressure in the supply line upstream of the pump 40 is constant. If necessary, the volumetric flow conveyed by the pump and its pressure can also be controlled as a function of the measured value determined by the flow measuring device 18. Alternatively, the volumetric flow that the pump 40 delivers can also be set by controlling the angular velocity of the pump 40. FIG. 7 shows a linearly increasing volumetric flow and a volumetric flow decreasing according to an exponential function. The pressure and the volumetric flow can be changed as desired depending on the setting of the pump 40, so that other courses are also conceivable which are not shown in the drawing.

[0107] The point in time t0 is dimensioned such that the heating device 5 can be heated to the heating temperature T1 before the pump 40 is operated in such a way that a constant volumetric flow can be generated. As soon as the heating device 5 has reached the heating temperature T1, thus, at time t0 in the present illustration, the multi-way valve is opened, that is to say the feed to the brewing device 6 is opened. The heating temperature T1 remains constant until time t1. When the multi-way valve is closed again at time t1, the heating device 5 can be switched off. Therefore, the heating temperature T1 decreases because the heater cools down. A further supply of energy to the heating device 5 is no longer necessary, so that no additional energy is required in the standby state.

[0108] FIG. 8 shows an exemplary example of a dosage regimen according to which the extraction agent 9 is fed to the brewing device 6 in several phases. A start phase of the pressure increase is provided before the point in time t0 when the pump 40 is put into operation. In this start phase, the volumetric flow increases. The multi-way valve 42 can be in the third position in order to build up pressure in the connection line 17 or in the second position in order to direct insufficiently preheated water into the line 44 leading to the wastewater. In this start phase, which runs in a time segment that lasts until time t0, the heating device 5 can be supplied with a volume D0 of the extraction agent 9 at an increasing pressure, which increases up to pressure p1. During the period t0−0 the volumetric flow increases; a volume D0 (ml) is conveyed, which is symbolized by the triangular area under the volumetric flow curve.

[0109] In a first phase, which runs in a time segment that lasts from a point in time t0 to t1, the multi-way valve 42 is in the first position, so that extraction agent 9 is passed through the heating device 5 into the connection line 17, through the multi-way valve 42 into the connection line 43 to the brewing device 6. The pump 40 remains in operation and the heating device 5 remains switched on as long as the heated extraction agent 19 is required to have the appropriate temperature for the brewing device 6. The supply of heat to the heating device 5 can also be interrupted if cooling is to take place in the first phase. During the period t1−t0 the volumetric flow is constant, a volume D1 (ml) is conveyed, which is symbolized by the rectangular area under the volumetric flow curve.

[0110] In a second phase, which runs in a time segment that lasts from a point in time t1 to t2, the multi-way valve 42 is in the second or third position, so that extraction agent 9 is not passed through the heating device 5 into the connection line 17 to the multi-way valve 42, but from the connection line 43 to the brewing device 6. The pump 40 is switched off and the heating device 5 remains switched on so that the extraction agent can reach the temperature required for the brewing device 6. The pressure can thus increase as a result of the heating of the extraction agent 9; according to the present embodiment, the pressure is p2 at time t2 and p1 at time t1. The pressure p2 is slightly higher than the pressure p1.

[0111] In a third phase, which runs in a time segment that lasts from a point in time t2 to t3, the multi-way valve 42 is in the first position, so that extraction agent 9 passes through the heating device 5 into the connection line 17 to the multi-way valve 42 and from the connection line 43 to the brewing device 6. The heated extraction agent 19 is thus conducted to the brewing device 6 during the third phase and comes into contact with the extract 10. If the extract 10 is in the form of a powder or a solid containing pores, the heated extraction agent 19 fills the pores in the third phase, that persist between the grains of the powder or that persist in the solid. The extract 10 is moistened by the heated extraction agent 19 in this third phase.

[0112] In the third phase, which runs in a time segment that lasts from a point in time t2 to t3, the pump 40 is switched on again or the volumetric flow is changed in such a way that a second volume D2 of the extraction agent 9 can be brought to a pressure p2 or maintained at the pressure p2. According to the present example, the pressure p2 differs from the pressure p1. According to this example, the pressure p2 is higher than the pressure p1. According to an embodiment not shown, the pressure p2 could also be lower than the pressure p1. In the third phase, the volumetric flow is also greater than in the first phase. The heat requirement for the heating device 5 can be adapted accordingly. In the present example, the opening time t3−t2 essentially corresponds to the opening time t1−t0; these opening times can also differ from one another according to an embodiment that is not shown. The closing time t2−t1 between the opening times can correspond to at least one of the opening times or can differ from the opening times. During the opening time, the multi-way valve is in the first position, during the closing time it is in one of the second or third positions, so that no heated extraction agent 19 is fed to the brewing device.

[0113] In the fourth phase, which runs in a time segment that lasts from a point in time t3 to t4, the pump 40 is switched off or its speed is reduced so that no extraction agent 9 is passed to the heating device 5. In this example, the closing time t4−t3 is shorter than the previous opening time t3−t2. During this short period of time, the pressure can remain essentially constant, that is to say it can keep the value p2. The temperature of the extraction agent 9 located in the heating device 5 can be increased, since no cold extraction agent can flow in.

[0114] In a fifth phase, which runs in a time segment that lasts from a point in time t4 to t5, the multi-way valve 42 again changes to the first position, so that a third volume D3 of the extraction agent 9 is reduced from pressure p2 to pressure p3 during the opening time. According to the present example, a pressure drop occurs during the fifth phase. The heated extraction agent 19 has the pressure p2 at time t4. At the point in time t5, the heated extraction agent 19 has the pressure p3. The pressure drop is linear in the fifth phase, but the pressure drop could also have a non-linear profile. According to an embodiment not shown, the pressure p3 could also be higher than the pressure p2. In the fifth phase, the volumetric flow is also smaller than in the third phase. The heat requirement for the heating device 5 can also be adapted accordingly. The opening time t5−t4 is longer than the opening time t1−t0 in the present example.

[0115] In the sixth phase, which follows the fifth phase, and which expires in a time segment that lasts from time t5 to t6, the multi-way valve 42 is shifted to the third position so that no heated extraction agent 19 is directed to the brewing device 6. In this example, the closing time t6−t5 is shorter than the previous opening time t5−t4. During this short period of time, the pressure in the connection line 17 is increased since a higher pressure is required for the subsequent seventh phase.

[0116] In a seventh phase, which runs in a time segment that lasts from a point in time t6 to t7, the multi-way valve is again shifted to the first position so that a fourth flow rate D4 of the extraction agent 9 can be increased from a pressure p4 to a pressure p5. The pressure is thus increased from pressure p4 to pressure p5 during the opening time t7−t6. The volumetric flow of the extraction agent 9, which is conveyed by the pump 40, increases, for example by increasing the angular velocity of the pump 40. The heated extraction agent 19 has the pressure p4 at time t6. At the point in time t7, the heated extraction agent 19 has the pressure p5. In the present example, the pressure profile is linear, but it could also have a non-linear profile.

[0117] FIGS. 7 and 8 show only by way of example two examples for a large number of possible dosage regimens for controlling the extraction process. Each of the dosage regimens can be stored in the memory unit 23 in order to be carried out when required by the instruction of a user.

[0118] It is obvious to a person skilled in the art that many further variants are possible in addition to the embodiments described without deviating from the inventive concept. The subject matter of the invention is therefore not restricted by the preceding description and is determined by the scope of protection which is defined by the claims. The broadest possible reading of the claims is authoritative for the interpretation of the claims or the description. In particular, the terms “contain” or “include” are to be interpreted in such a way that they refer to elements, components, or steps in a non-exclusive meaning, which is intended to indicate that the elements, components, or steps can be present or are used that they can be combined with other elements, components or steps that are not explicitly mentioned. When the claims relate to an element or component from a group which may consist of A, B, C to N elements or components, this formulation should be interpreted in such a way that only a single element of that group is required, and not one combination of A and N, B and N, or any other combination of two or more elements or components of this group.