Coffee machine and coffee bean baking treatment method

Abstract

The invention discloses a coffee machine and a coffee bean baking treatment method, the coffee machine comprises a bean storage bin, a grinder, a heater and a powder screening device, the bean storage bin is provided with a bin outlet, the grinder is provided with a first inlet and a first outlet, and the first inlet of the grinder is connected with the bin outlet. The heater is provided with a baking cavity which is provided with a second inlet and a second outlet, the second inlet is connected with the first outlet, and the powder screening device is connected with the second outlet of the heater. The ground coffee powder is subjected to secondary baking, so that impurities adsorbed by the coffee beans due to long-time moisture absorption can be effectively removed, the peculiar smell of the coffee powder is removed, the cooking degree of the coffee powder is further improved, and the coffee flavor is increased. And compared with a treatment mode of baking and then grinding the green coffee beans, the coffee machine disclosed by the invention has the advantages that the process treatment time is short, the coffee can be quickly brewed, and the user experience is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of coffee processing, and in particular to a coffee machine and a method for roasting coffee beans. Background Art

[0002] In the daily coffee brewing process, the long-stored cooked coffee beans are prone to reduce the flavor substances and increase the odor due to improper storage. Directly grinding the long-stored coffee beans and brewing coffee will damage the coffee flavor and affect the brewing experience. Summary of the invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a coffee machine, which performs secondary roasting on ground coffee powder and combines a specific particle size screening process to remove the odor of coffee powder, remove staleness and enhance aroma, increase coffee flavor, and enhance user brewing experience.

[0004] Another object of the present invention is to provide a method for roasting coffee beans.

[0005] According to an embodiment of the present invention, the coffee machine includes: a bean storage bin having an outlet; a grinder having a first inlet and a first outlet, the first inlet of the grinder being connected to the outlet; a heater having a roasting chamber, the roasting chamber having a second inlet and a second outlet, the second inlet being connected to the first outlet; and a powder sifter connected to the second outlet of the heater.

[0006] According to the coffee machine of the embodiment of the present invention, the bean storage bin is used to store the pre-roasted roasted coffee beans, and the grinder is connected to the bean storage bin. Before the coffee beverage making process, the roasted coffee beans in the bean storage bin that may affect the flavor due to long-term storage are first ground, and the ground roasted coffee powder is secondarily roasted by the heater, which can effectively remove the impurities adsorbed by the roasted coffee beans in the bean storage bin due to long-term moisture absorption, remove the odor of the roasted coffee powder, and further improve the maturity of the ground coffee powder, further increase the flavor and mellow taste of the coffee beverage. In addition, compared with the processing method of directly roasting and grinding the raw coffee beans, the coffee machine of the present invention has a shorter processing time, can quickly brew coffee, and improve the user experience.

[0007] In some embodiments, the heater includes: a heating container, the inner cavity of the heating container constitutes the baking cavity; a graphene layer, the graphene layer is arranged on the heating container, and is used to cover the baking cavity and heat the baking cavity; further, the graphene layer is evenly coated on the heating container, so as to achieve uniform heating of the baking cavity.

[0008] In some specific embodiments, the graphene layer is coated on the inner surface of the heating container, and the heating container is a heat conductor; the heater includes a heating element connected to the heating container.

[0009] In other specific embodiments, the heating container is a heat conductor, the graphene layer is coated on the outer surface of the heating container, and the graphene layer serves as a heating element that is powered by electricity.

[0010] Specifically, an insulating layer is provided between the graphene layer and the heating container.

[0011] Furthermore, the outer side of the graphene layer is covered with a heat insulation layer.

[0012] In some embodiments, the heater is configured as a tube, the top of the tube forms the second inlet, and the bottom of the tube forms the second outlet.

[0013] The coffee bean roasting method according to an embodiment of the present invention comprises the following steps: feeding a predetermined amount of cooked coffee beans into a grinder for grinding to generate coffee powder; feeding the coffee powder into a roasting chamber for heating to generate roasted coffee powder; and feeding the coffee powder into a powder sifter after roasting to obtain coffee powder of a predetermined particle size.

[0014] According to the coffee bean roasting method of the embodiment of the present invention, the ground coffee powder is first ground and then roasted to effectively remove impurities adsorbed by the coffee beans due to long-term moisture absorption, remove the peculiar smell of the coffee powder, and further improve the maturity of the coffee powder and increase the coffee flavor. In addition, compared with the method of roasting and then grinding the raw coffee beans, the coffee machine of the present invention has a shorter process time, can quickly brew coffee, and improve the user experience.

[0015] Specifically, the coffee powder needs to reach 105-120° C. during roasting.

[0016] In some embodiments, the predetermined particle size of the powder sifter is between 35 and 100 um.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0019] Figure 1 is a schematic structural diagram of a coffee machine according to an embodiment of the present invention;

[0020] Figure 2is a schematic diagram of a heater according to some embodiments of the present invention;

[0021] Figure 3 is a schematic structural diagram of a heater according to some other embodiments of the present invention;

[0022] Figure 4 4 is a flowchart of a method for roasting coffee beans according to an embodiment of the present invention.

[0023] Reference numerals:

[0024] Coffee machine 100;

[0025] Bean storage bin 1; outlet 11;

[0026] grinder 2; first inlet 21; first outlet 22;

[0027] Heater 3; baking chamber 30; graphene layer 301; second inlet 31; second outlet 32; heating container 33; heating element 34; insulating layer 35; heat insulation layer 36;

[0028] Powder sifter 4;

[0029] Coffee machine body 5; powder outlet 51. DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0031] In the description of the present invention, it should be understood that the terms "center", "upper", "lower", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0032] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] Reference below Figure 1-Figure 3 A coffee machine 100 according to an embodiment of the present invention is described.

[0034] The coffee machine 100 according to the embodiment of the present invention comprises: a bean storage bin 1, a grinder 2, a heater 3 and a powder sifter 4. The coffee beans are stored in the bean storage bin 1. The bean storage bin 1 has a bin outlet 11. The grinder 2 has a first inlet 21 and a first outlet 22. The first inlet 21 of the grinder 2 is connected to the bin outlet 11. When the coffee machine 100 is working, the coffee beans are transported out from the bin outlet 11, and the coffee beans enter the grinder 2 through the first inlet 21. The grinder 2 grinds the coffee beans into coffee powder. It can be understood that the beans stored in the bean storage bin 1 are cooked coffee beans, and the grinder 2 grinds the roasted coffee beans into coffee powder.

[0035] In daily use, improper storage of roasted coffee beans may reduce the flavor substances, and directly grinding and brewing the long-stored roasted coffee beans into coffee may damage the flavor of the coffee. The coffee machine 100 of the present invention is provided with a heater 3, which performs secondary roasting on the ground coffee powder to remove the staleness and enhance the aroma, thereby improving the user's brewing experience.

[0036] The heater 3 has a roasting chamber 30, and the roasting chamber 30 has a second inlet 31 and a second outlet 32, and the second inlet 31 is connected to the first outlet 22. The coffee powder is delivered from the first outlet 22 of the grinder 2 and can enter the roasting chamber 30 through the second inlet 31. The roasting chamber 30 heats the coffee powder, which can effectively remove impurities adsorbed by the coffee beans due to long-term moisture absorption, remove the peculiar smell of the coffee powder, and further improve the maturity of the coffee powder and increase the coffee flavor.

[0037] Existing coffee machines also have a component for roasting green coffee beans, which can prevent the cooked coffee beans from absorbing moisture after being left for a long time. However, the coffee machine process for roasting green coffee beans takes a long time, and the waiting time for brewing coffee each time is too long, which affects the user experience. The coffee machine 100 of the present invention processes the roasted cooked coffee beans, grinds the cooked coffee beans into coffee powder, and then roasts the coffee powder again. The coffee machine 100 of the present invention has a short process processing time, can quickly brew coffee, and improve the user experience.

[0038] It is understandable that the particle size of coffee powder will affect the flavor of the final brewed coffee. When the particle size of coffee powder is too small, it is easy for the coffee powder to emit a white smell that affects the flavor during the brewing process; and when the particle size of coffee powder is too large, the flavor substances in the coffee powder are difficult to precipitate, which will also affect the flavor of the coffee.

[0039] The coffee machine 100 of the present invention also includes a powder sifter 4, which is connected to the second outlet 32 ​​of the heater 3. The coffee powder after secondary baking enters the powder sifter 4 through the second outlet 32. The powder sifter 4 can sieve out the coffee powder whose particle size does not meet the requirements and retain the coffee powder whose particle size is within a preset range, so as to improve the taste of the final brewed coffee and enhance the user experience.

[0040] In some embodiments of the present invention, the user can interactively control the coffee machine 100 through the display interface, select the grinding particle size of the powder sifter 4, and obtain the second-roasted coffee powder that meets the user's needs to complete the subsequent coffee beverage production process and enhance the roasted flavor of the old roasted coffee beans.

[0041] According to the coffee machine 100 of the embodiment of the present invention, by performing a secondary roasting on the ground coffee powder, impurities adsorbed by the coffee beans due to long-term moisture absorption can be effectively removed, the peculiar smell of the coffee powder can be removed, and the maturity of the coffee powder can be further improved to enhance the coffee flavor. In addition, compared with the processing method of roasting and then grinding the raw coffee beans, the coffee machine 100 of the present invention has a shorter process processing time, can quickly brew coffee, and improve the user experience.

[0042] In some embodiments of the present invention, Figure 1 As shown, there can be multiple bean storage bins 1, which can increase the storage capacity of coffee beans. One refill can be used for a longer time, reducing the time of frequent refills and improving the convenience of use. In addition, coffee beans of different flavors can be stored in different bean storage bins 1, and the coffee machine 100 can brew coffee of different flavors, thereby improving the functionality of the coffee machine 100.

[0043] In some embodiments of the present invention, a plurality of grinding heads are provided in the grinder 2, and the plurality of grinding heads are arranged at intervals. The coffee machine 100 of the present invention can control the particle size of the ground coffee powder by adjusting the gaps between the plurality of grinding heads to improve the taste of the final brewed coffee.

[0044] In some specific embodiments of the present invention, multiple grinding heads grind the coffee beans into a particle size of 40um-100um.

[0045] In some embodiments, Figure 1 As shown, the heater 3 is configured as a tube. When the coffee machine 100 is working, the heater 3 is vertically arranged, the top of the tube forms a second inlet 31, and the bottom of the tube forms a second outlet 32.

[0046] The coffee powder delivered from the grinder 2 enters the heater 3 from the second inlet 31 at the top of the tube body, and is delivered from the second outlet 32 ​​at the bottom of the tube body. The coffee powder can naturally fall into the roasting chamber 30 under the action of gravity, and then escape from the second outlet 32 ​​under the action of gravity. The coffee powder can be delivered under the action of its own gravity, which saves the need to set a delivery component in the heater 3, reduces the weight of the coffee machine 100 while saving manufacturing costs, and is easy to use.

[0047] In addition, when the heater 3 is a vertically arranged tube, the time for the coffee powder to be heated in the roasting chamber 30 is substantially the same as the time for the coffee powder to fall freely in the roasting chamber 30. At this time, by designing the length of the tube of the heater 3, the time for heating the coffee powder can be very conveniently designed, thereby controlling the degree of secondary roasting.

[0048] Of course, the shape of the heater 3 of the present application is not limited thereto. For example, the upper end of the heater 3 is funnel-shaped to hold coffee powder, and the lower end is provided with multiple forks to guide the coffee powder to multiple powder sifters 4. For another example, a spiral guide vane may be provided in the heater 3, and after the coffee powder is poured into the roasting chamber 30, it is guided to the powder sifter 4 along the spiral guide vane.

[0049] In some embodiments, Figure 2 and Figure 3 As shown, the heater 3 comprises: a heating container 33 and a graphene layer 301, and the inner cavity of the heating container 33 constitutes a baking cavity 30. The graphene layer 301 is arranged on the heating container 33, and is used to cover the baking cavity 30 to achieve uniform heating of the baking cavity 30.

[0050] The use of the graphene layer 301 is an innovative application of the coffee machine 100. Graphene is a material in which carbon atoms are tightly stacked into a single-layer two-dimensional honeycomb lattice structure. Graphene has very good thermal conductivity, and the thermal conductivity of some single-layer graphene can even exceed 5000W / mK.

[0051] Therefore, the graphene layer 301 is selected to be disposed on the heating container 33 and cover the roasting chamber 30. The graphene layer 301 can evenly conduct the heat obtained by itself on the entire graphene layer 301, thereby evenly heating the roasting chamber 30. In this way, the coffee powder can be evenly heated, avoiding the situation where some coffee powder is not heated enough to cause the coffee powder to have a strange smell, and also avoiding the situation where some coffee powder is overheated to cause a burnt smell.

[0052] It should be noted here that the design goal of the coffee machine 100 of the present application is to remove the odor in the coffee powder by accurately controlling the heating temperature and heating time during the secondary roasting process of the cooked coffee beans, especially during the roasting process of the heater 3. If the coffee powder is damp, it needs to be dried to remove the odor, and the required heat accuracy is required to be high. However, the present solution uses the graphene layer 301 to heat the coffee powder, and the extremely high thermal conductivity is conducive to controlling the heating temperature of the coffee powder and the amount of heat received by the coffee powder. Therefore, the use of the graphene layer 301 in the coffee machine 100 can improve the control accuracy.

[0053] In some specific embodiments, Figure 2 As shown, the graphene layer 301 is coated on the inner surface of the heating container 33, the heating container 33 is a heat conductor, and the heater 3 includes a heating element 34 connected to the heating container 33. That is to say, in this scheme, the graphene layer 301 itself is used as a heat equalizer. When the heating element 34 generates heat, the heat is transferred to the heat-conducting heating container 33, and the heating container 33 then conducts the heat to the graphene layer 301. Since the graphene layer 301 has a high thermal conductivity, even if the heat transferred from the heating container 33 to the graphene layer 301 is different at different places, the heat will eventually tend to be evenly distributed on the graphene layer 301, so that the graphene layer 301 can evenly heat the coffee powder in the roasting chamber 30.

[0054] Among them, by coating the graphene layer 301 on the inner surface of the heating container 33, it is not only convenient for processing, but also conducive to maintaining a seamless connection between the graphene layer 301 and the heating container 33, so that the efficiency of heat transfer from the heating container 33 to the graphene layer 301 can be improved. Moreover, this arrangement is convenient for maintaining the uniformity of the thickness of the graphene layer 301 and reducing unnecessary waste. In addition, the heating container 33 is surrounded by the outside of the graphene layer 301, which is conducive to radiating the heat of the graphene layer 301 inward as much as possible, reducing heat waste.

[0055] Here, the structure of the heating element 34 and the relative position of the heating element 34 and the heating container 33 are not limited. For example, the heating element 34 is a heating tube or a heating net, and the heating element 34 is wrapped around the surface of the heating container 33. For another example, the heating element 34 is a heating wire embedded in the heating container 33. The heating element 34 can adopt the heating element structure of household appliances known in the prior art.

[0056] In other specific embodiments, Figure 3As shown, the graphene layer 301 is a heating element 34 that is powered on. That is, the graphene layer 301 is conductive, and the graphene layer 301 generates heat when powered on. Moreover, when the graphene layer 301 generates heat when powered on, the graphene layer 301 still has a high thermal conductivity. Even if the heat generated in different places of the graphene layer 301 is different, the heat will eventually tend to be evenly distributed on the graphene layer 301, so that the graphene layer 301 can evenly heat the coffee powder in the roasting chamber 30.

[0057] Specifically, the heating container 33 is a heat conductor, and the graphene layer 301 is coated on the outer surface of the heating container 33. Here, the graphene layer 301 is coated on the outer surface of the heating container 33, and the heating container 33 is used to support the graphene layer 301, which is not only convenient for processing, but also conducive to maintaining a seamless connection between the graphene layer 301 and the heating container 33, so that the efficiency of heat transfer from the heating container 33 to the graphene layer 301 can be improved. Moreover, in this setting mode, the graphene layer 301 does not need to be set too thick by using the heating container 33 for support, which can save the material of the graphene layer 301.

[0058] Specifically, an insulating layer 35 is provided between the graphene layer 301 and the heating container 33. Since the coffee powder may contain a certain amount of humidity, the insulating layer 35 is used to separate the graphene layer 301 and the heating container 33 to prevent the coffee powder from being electrified, thereby improving the safety of use.

[0059] Optionally, the insulating layer is a ceramic coating, which ensures heat conduction.

[0060] Furthermore, the outer side of the graphene layer 301 is covered with a heat insulation layer 36 , so that the heat insulation layer 36 surrounds the outer side of the graphene layer 301 , which is conducive to radiating as much heat of the graphene layer 301 inward as possible, thereby reducing heat waste.

[0061] Optionally, the heating container 33 is a metal container, which improves the structural strength of the heating container 33 and the support reliability of the graphene layer 301. In addition, the metal container can also achieve a certain thermal conductivity, and improve the shock and impact resistance in the bump, thereby extending the service life of the heater 3.

[0062] Further optionally, the heating container 33 is made of SUS304 or aluminum alloy.

[0063] In some optional embodiments, such as Figure 2 and Figure 3 As shown, the heating container 33 is constructed in a tubular shape, and a baking chamber 30 is defined inside the heating container 33 . The second outlet 32 ​​is arranged at the top of the heating container 33 , and the second inlet 31 is arranged at the bottom of the heating container 33 .

[0064] The heating container 33 is a heat conductor, and the heating element 34 heats the heating container 33. The heating container 33 radiates heat into the roasting chamber 30. The coffee powder is heated after entering the roasting chamber 30, which can effectively remove impurities adsorbed by the coffee beans due to long-term moisture absorption, remove the peculiar smell of the coffee powder, and further improve the maturity of the coffee powder, thereby increasing the coffee flavor.

[0065] The coffee powder enters the roasting chamber 30 from the second inlet 31 at the top of the heating container 33, and then the coffee powder slides freely under the action of gravity. The coffee powder is heated by radiation during the sliding process in the roasting chamber 30, and the coffee powder is evenly heated to avoid the situation where some coffee powder is not heated enough, resulting in the coffee powder having a strange smell. Compared with heating the coffee powder by hot air or other methods, the heater 3 of the coffee machine 100 of the present invention will not blow the coffee powder everywhere to cause loss, and the coffee powder can be roasted twice during the sliding process. The heating effect of the heater 3 is high, and the coffee machine 100 of the present invention has a short process processing time, which can quickly brew coffee and improve the user experience.

[0066] The coffee powder is heated by radiation during the process of sliding down in the roasting chamber 30, and the effective heating time of the coffee powder is limited by the pressure difference on both sides of the roasting chamber 30 and the inclination angle of the roasting chamber 30. The axial length and inclination angle of the heating container 33 can be selected according to actual use to improve the roasting effect of the coffee powder.

[0067] Optionally, the heater 3 further includes: a non-stick layer attached to the inner surface of the heating container 33. The non-stick layer can prevent the coffee powder from adhering to the inner surface of the heating container 33, effectively reduce the adhesion rate of the coffee powder, improve the powder yield, reduce the number of cleaning times of the roasting chamber 30, and facilitate use. In addition, when the coffee powder adheres to the inner surface of the heating container 33, the heater 3 will overheat the coffee powder, and even if the coffee powder falls off the inner surface of the heating container 33, it will affect the maturity of the coffee powder and the coffee flavor.

[0068] In some embodiments of the present invention, the powder sifter 4 can screen out coffee powder whose particle size does not meet the requirements and screen out coffee powder whose particle size is within a preset range. By setting the powder sifter 4, coffee powder with uniform particle size can be obtained, and the brewing flavor is sufficient, while avoiding the change of the roasting degree of the coffee powder due to uneven secondary roasting, thereby affecting the taste.

[0069] Specifically, the powder sifter 4 can screen the coffee powder into one particle size specification or multiple particle size specifications. Figure 1 In the example shown, all the sifters 4 can sieve the coffee powder into one particle size specification. Figure 1In the example shown, one part of the powder sifters 4 sifts the coffee powder into one particle size specification, and the other part of the powder sifters 4 sifts the coffee powder into another particle size specification. When the two sifters work at the same time, coffee powder of two particle sizes can be obtained at the same time. When the two sifters switch work, the coffee machine obtains coffee powder of one particle size specification at a time.

[0070] In some embodiments of the present invention, the particle size screening range of the powder sifter 4 is ±10% um of the predetermined screening particle size. For example, when the powder sifter 4 is predetermined to screen coffee powder with a particle size of 50 um, the powder sifter can screen out coffee powder with a particle size of 45 um-55 um. For another example, when the powder sifter 4 is predetermined to screen coffee powder with a particle size of 100 um, the powder sifter can screen out coffee powder with a particle size of 90 um-110 um.

[0071] Of course, in the present application, there is no limitation on the particle size screening range of the powder sifter 4. For example, the particle size screening range of the powder sifter 4 is ±5% um, ±15% um, etc. of the predetermined screening particle size.

[0072] In some embodiments of the present invention, Figure 1 As shown, there are multiple powder sifters 4, which can quickly sift out a large amount of coffee powder in a predetermined particle size, thereby improving work efficiency. The coffee machine 100 of the present invention has a short process processing time, can quickly brew coffee, and improve user experience.

[0073] In other embodiments of the present invention, there are multiple powder sifters 4, and the multiple powder sifters 4 can be set with different particle size specifications to sift out coffee powder of various particle sizes, thereby improving the functionality of the coffee machine 100.

[0074] In some embodiments of the present invention, the powder sifter 4 can rotate along the axis of the powder sifter 4 , and centrifugal rotation can be superimposed to improve the mesh passing efficiency and enhance the working efficiency of the powder sifter 4 .

[0075] In some embodiments of the present invention, Figure 1 As shown, the coffee machine 100 also includes a coffee machine body 5, and the bean storage bin 1, the grinder 2, the heater 3 and the powder sifter 4 are all arranged in the coffee machine body 5. A powder outlet 51 is arranged at the bottom of the coffee machine body 5, and the powder outlet 51 is connected to the powder sifter 4, and the sifted coffee powder is transported out from the powder outlet 51.

[0076] In some embodiments, the bean storage bin 1, grinder 2, heater 3 and powder sifter 4 are arranged at intervals in the vertical direction, and the coffee beans can automatically enter the next process under the action of their own gravity, thereby saving manufacturing costs and reducing the weight of the coffee machine 100 for ease of use.

[0077] According to the roasting method of coffee beans of the embodiment of the present invention, refer to Figure 4 , including the following steps:

[0078] S1: A predetermined amount of cooked coffee beans is sent to a grinder 2 for grinding to generate coffee powder.

[0079] S2: The coffee powder is sent to the roasting chamber 30 for heating to generate roasted coffee powder.

[0080] Heating the coffee powder can effectively remove impurities adsorbed by the cooked coffee beans due to long-term moisture absorption, remove the odor of the coffee powder, and further improve the maturity of the coffee powder and increase the coffee flavor.

[0081] S3: After roasting, the coffee powder is sent to the powder sifter 4 to obtain coffee powder with a predetermined particle size. The powder sifter 4 retains coffee powder with a particle size within a preset range to improve the taste of the final brewed coffee and enhance the user experience.

[0082] The coffee powder obtained in this way has uniform particles, rich brewing flavor, and improves the user experience.

[0083] In some embodiments, the coffee powder needs to reach 105-120° C. The heater 3 bakes the coffee powder to 105-120° C. In this temperature range, impurities adsorbed by the coffee beans due to long-term moisture absorption can be effectively removed, and the odor of the coffee powder can be removed. At the same time, the Maillard reaction will not occur due to excessive temperature, which will further increase the maturity of the coffee powder and change the flavor.

[0084] In some embodiments, the predetermined particle size of the powder sifter 4 is 35 to 100 um. The particle size of the coffee powder will affect the flavor of the final brewed coffee. When the particle size of the coffee powder is too small, the coffee powder will easily emit a white taste that affects the flavor during the brewing process; and when the particle size of the coffee powder is too large, the flavor substances in the coffee powder are difficult to precipitate, which will also affect the flavor of the coffee. The predetermined particle size of the powder sifter 4 is 35 to 100 um. The powder sifter 4 retains coffee powder with a particle size within the preset range to improve the taste of the final brewed coffee and enhance the user experience.

[0085] Since the powder sifter 4 needs to sift the coffee powder machine, in order to achieve the amount of coffee beans for one cup of coffee, the amount of coffee beans ground each time is 1.2-1.5 times the amount of conventional coffee beans, ensuring the rich aroma of the brewed coffee.

[0086] The structures and operations of other components of the coffee machine according to the embodiment of the present invention, such as the powder sifter 4 and the liquid outlet control device, are well known to those skilled in the art and will not be described in detail here.

[0087] In the description of this specification, the description with reference to the terms "embodiment", "example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0088] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A coffee machine, characterized in that: include: A bean storage bin, wherein the bean storage bin has an outlet; A grinder, the grinder having a first inlet and a first outlet, the first inlet of the grinder being connected to the outlet; a heater, the heater having a baking chamber, the baking chamber having a second inlet and a second outlet, the second inlet being connected to the first outlet; A powder sifter is connected to the second outlet of the heater.

2. The coffee machine according to claim 1, characterized in that The heater comprises: A heating container, the inner cavity of which constitutes the baking cavity; A graphene layer is disposed on the heating container and is used to heat the baking chamber.

3. The coffee machine according to claim 2, characterized in that The graphene layer is coated on the inner surface of the heating container, and the heating container is a heat conductor; The heater includes a heating element connected to the heating container.

4. The coffee machine according to claim 2, characterized in that The graphene layer is a heating element that is powered by electricity.

5. The coffee machine according to claim 4, characterized in that The heating container is a heat conductor, the graphene layer is coated on the outer surface of the heating container, and an insulating layer is provided between the graphene layer and the heating container.

6. The coffee machine according to claim 4, characterized in that The outer side of the graphene layer is covered with a heat insulation layer.

7. The coffee machine according to any one of claims 1 to 6, characterized in that: The heater is configured as a tube, the top of the tube forms the second inlet, and the bottom of the tube forms the second outlet.

8. A method for roasting coffee beans, characterized in that: The coffee beans are first ground and then roasted using the coffee machine as claimed in claim 1, comprising the following steps: Sending a predetermined amount of cooked coffee beans to a grinder for grinding to produce coffee powder; delivering the coffee powder to a roasting chamber for heating to generate roasted coffee powder; After roasting, the coffee powder is sent to a powder sifter to obtain coffee powder with a predetermined particle size.

9. The method for roasting coffee beans according to claim 8, characterized in that: The coffee powder is roasted at a temperature of 105-120°C.

10. The method for roasting coffee beans according to claim 8, characterized in that: The predetermined particle size of the powder sifter is 35 to 100 um.

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