Embodiments of the present invention generally relate to roasting of coffee beans, and particularly, to a method, apparatus, and computer program product for identifying initial roasting degree of coffee beans.
Enjoy fresher coffee is now becoming a great need to consumers. In order to meet different requirements of customers, segmented roasting has been proposed. As an example, for conventional green coffee beans, the moisture content usually ranges from 9% to 12% with a tolerant error of 0.3%. When the segmented roasting is applied, there will be different levels of partially roasted coffee beans that have different initial states such as moisture content. For example, the moisture content of some coffee beans could be very close to 5%. The consumers could buy such partially roasted coffee beans and perform home roasting according to their personal preferences.
It would be appreciated that for the coffee beans with different levels of partial roasting, initial states of the coffee beans will be different. As used herein, the term “initial state” refers to one or more properties of the coffee beans to be consumed by the consumers. For example, the initial state of coffee beans may include initial moisture content, heat capacity, density, color, or any other properties of the coffee beans. In particular, for those partially roasted coffee beans, the initial state of coffee beans is at least indicative of the initial roasting degree of the coffee beans.
When the coffee beans are roasted by the consumers, the initial roasting degree of the coffee beans will influence the roasting effect. For example, if the coffee beans contain more moisture content, the heating temperature of the coffee beans in the first phase normally should be slowly increased. This would facilitate the heat evenly penetrating into the core of the coffee beans and make the water evenly steaming out from the core to the surface of the coffee beans. Therefore, it would be beneficial to select the roasting profile based on the initial roasting degree of the input coffee beans.
At present, however, coffee roasters usually pre-set a roasting profile to all the consumers regardless of the initial roasting degree of the coffee beans. Some coffee roasters allow the consumers to decide the roasting temperature and time. For common customers, however, manual setting of the roasting profile would probably make home roasting obscure.
In order to ensure the roasting effect and to provoke the passion and enhance the pleasure of home roasting, there is need in the art for a solution that is capable of automatically identifying the initial roasting degree of coffee beans such that the roasting profile may be controlled accordingly.
In order to address the above and other potential problems, embodiments of the present invention propose a method, apparatus, and computer program product for identifying initial roasting degree of the coffee beans.
In one aspect, embodiments of the present invention provide a method for identifying an initial roasting degree of coffee beans. The method comprises steps of: measuring information indicating temperature change of the coffee beans while the coffee beans are roasted; and identifying the initial roasting degree of the coffee beans at least partially based on the measured information. Other embodiments in this regard include a corresponding computer program product for identifying an initial roasting degree of coffee beans.
In another aspect, embodiments of the present invention provide an apparatus for identifying an initial roasting degree of coffee beans. The apparatus comprises: a measuring unit configured to measure information indicating temperature change of the coffee beans while the coffee beans are roasted; and an identifying unit configured to identify the initial roasting degree of the coffee beans at least partially based on the measured information.
These embodiments of the present invention can be implemented to realize one or more of the following advantages. By measuring temperature change of the beans over a time period, it is possible to accurately identify the initial roasting degree of coffee beans within a relatively short period. In some embodiments, the initial roasting degree may be directly calculated. As such, the initial roasting degree of coffee beans can be identified without reliance on too much prior knowledge and experiments. Alternatively, predetermined associations between the temperature changes and different initial roasting degree of reference coffee beans may be established and used for identification of initial state. In this way, the initial roasting degree of the coffee beans can be identified quickly with low costs. By utilizing the identified initial roasting degree to control the roasting profile, good roasting effect can be achieved.
Other features and advantages of embodiments of the present invention will also be understood from the following description of exemplary embodiments when read in conjunction with the accompanying drawings, which illustrate, by way of example and principles of the present invention.
The details of one or more embodiments of the present invention are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the invention will become apparent from the description, the drawings, and the claims, wherein:
Throughout the figures, same or similar reference numbers indicates same or similar elements.
In general, embodiments of the present invention provide a method, apparatus, and computer program product for identifying an initial roasting degree of coffee beans. For identifying a roast degree of coffee beans, we may classify the degrees from 0 (fresh green beans without any roasting) to 10 (fully and darkest roasted). In accordance with embodiments of the present invention, the initial roasting degree of coffee beans is identified within a relatively short period after the coffee beans are roasted. In some embodiments, measured temperature change of the coffee beans is compared against predetermined associations between temperature changes and the initial roasting degree of reference coffee beans. By referring to such associations, the initial roasting degree of the coffee beans may be identified efficiently and accurately. Alternatively or additionally, in some embodiments, it is also possible to identify the initial roasting degree by calculating the heat capacity of the coffee beans based on the measured temperature change.
Reference is now made to
At step S101, information indicating temperature change of the coffee beans is measured while the coffee beans are being roasted. As used herein, the temperature of the coffee beans may be the coffee beans' surface temperature. In some alternative embodiments, the temperature of environment in which the coffee beans are located (such as the ambient temperature) may be used as an estimation of the temperature of the coffee beans.
In accordance with embodiments of the present invention, the temperature change may be represented in various manners. For example, in some exemplary embodiments, the temperature change is the amount of the temperature change of the coffee beans within a predefined time period. Alternatively or additionally, the temperature change is in the form of elapsed time period during which the coffee beans are roasted from a predefined initial temperature to a predefined target temperature. Exemplary embodiments of the measured information will be detailed below.
In order to measure the information indicating the temperature change, a temperature sensor may be utilized. For example, the temperature sensor may be arranged in the roasting chamber of the coffee roaster. After the coffee beans are fed into the roasting chamber, the temperature sensor is configured to continuously or periodically sense and record the surface temperatures of the coffee beans to thereby measure the temperature change over a given time period. Moreover, in some exemplary embodiments, the coffee roaster is equipped with a timer to detect relevant time periods in measuring the temperature change.
In some exemplary embodiments, in order to facilitate the measurement of the information indicating the temperature change and the identification the initial roasting degree of the coffee beans, the roasting chamber is heated to a certain temperature before the coffee beans are fed and roasted. The pre-heating of the roasting chamber would be beneficial in terms of energy saving. Moreover, such “hot start” may apply suitable temperature to the coffee beans immediately with right enough heat permeation to the core of the coffee beans. In this way, the temperature balanced period is shortened.
The method 100 then proceeds to step S102, where the initial roasting degree of the coffee beans is identified at least partially based on the information measured at step S101. Depending on different forms of the measured information, embodiments of the present invention may identify the initial roasting degree in various different manners.
For example, in some exemplary embodiments, one or more properties of the coffee beans may be directly calculated based on the measured information indicating the temperature change of the coffee beans. Then the initial roasting degree of the coffee beans is identified based on predetermined associations between the calculated one or more properties and the initial roasting degree of the coffee beans. Exemplary embodiments in this regard will be discussed later.
Alternatively or additionally, in some exemplary embodiments, the associations between the temperature changes and initial roasting degree of various types of reference coffee beans are determined and stored in advance in testing phase. As used herein, the term “reference coffee” refers to those coffee beans whose initial roasting degree and possibly other relevant properties are known. In such embodiments, the initial roasting degree of the coffee beans is identified based on comparison between the measured information and the corresponding information as indicated in the predetermined associations. Exemplary embodiments in this regard will be discussed later.
Specifically, in some exemplary embodiments, the method 100 may be performed in an early stage of the roasting process. For example, the measurement and identification may begin immediately after the coffee beans are fed into the roasting chamber. Since embodiments of the present invention are capable of identifying the initial roasting degree of the coffee beans in a relatively short time period, in this way, the roasting profile for the remaining of the roasting may be controlled accordingly. For example, if it is found that the current roasting profile is not suitable for the identified initial roasting degree of the coffee beans, it is possible to select a suitable roasting profile based on the identified initial roasting degree and replace the current one.
It would be appreciated that in accordance with embodiments of the present invention, the initial roasting degree can be identified upon consumption of the coffee beans. In this way, potential effects due to change of the initial roasting degree during storage, shipment and/or sale of the coffee beans are eliminated. For example, the initial roasting degree that is detected in advance, for example, by the providers would probably be inaccurate since the moisture content usually changes over time due to loss or absorption of moisture depending on the ambient temperature. Rather, in accordance with embodiments of the present invention, the exact initial roasting degree of the coffee beans at the time of consumption can be identified.
It should be noted that the early start of the method 100 is not necessarily required in all the cases. For example, in some alternative embodiments, the measurement and identification may be initiated by the consumer. Additionally, automatic control of the roasting profile is optional as well. For example, in some alternative embodiments, the identified initial roasting degree and any relevant information may be simply displayed to the consumer, for example, via a display on the coffee roaster or any other appropriate manners. Additionally or alternatively, a suggested roasting profile, which is determined based on the identified initial roasting degree of the coffee beans, may be displayed to the consumer. As such, the consumer is capable manually changing the roasting profile according to the displayed information.
As shown in
Then, after the coffee beans are roasted for a predefined time period (denoted as t), the reached temperature Tm of the coffee beans is measured at step S202. In this embodiment, elapse of the time period is detected by a timer. Accordingly, amount of the temperature change (denoted as ΔT) of the coffee beans over the time period t is calculated as follows:
ΔT=Tm−T0 (1)
At step S203, the quantity of heat (denoted as Q) applied to the coffee beans within the time period t is estimated. In some exemplary embodiments, the quantity of heat Q applied to the coffee beans may be estimated based on quantity of heat produced by the coffee roaster during the time period t. For example, in some embodiments, the quantity of heat Q is calculated as follows:
Q=η·P·t (2)
where η and P represent the heat efficiency and power of the coffee roaster, respectively. It would be appreciated that for a given coffee roaster, the heat efficiency η and power P are known.
The method 200 then proceeds to step S204, where the weight (denoted as M) of the coffee beans fed into the roasting chamber is obtained. In some exemplary embodiments, the weight M is predetermined. That is, in those embodiments, the consumer is only allowed to feed specified weight of coffee beans into the roasting chamber each time. For example, in some exemplary embodiments, the coffee roaster may provide several optional weights for consumer's selection. Alternatively, the weight M is received from the user. For example, the coffee roaster may provide a mechanism that allows the user to input the weight of the coffee beans fed into the roasting chamber. Alternatively or additionally, in some exemplary embodiments, a weight sensor may be arranged in the coffee roaster to measure the weight of coffee beans fed into the roasting chamber.
Next, at step S205, the heat capacity (denoted as C) of the coffee beans is calculated based on the amount of the temperature change ΔT within the time period t, the quantity of heat Q, and the weight M of the coffee beans. In some exemplary embodiments, the heat capacity C is calculated as follows:
C=Q/(M·ΔT) (3)
Given the calculated heat capacity C of the coffee beans, the initial roasting degree of the coffee beans is identified at step S206 based on prior knowledge. More specifically, for various types of reference coffee beans with different initial roasting degree, their associated heat capacities (denoted as Cr) are measured and stored in advance. Accordingly, the calculated heat capacity C of the coffee beans is compared with the pre-stored heat capacities Cr to find a most matching one. The initial roasting degree corresponding to the matching heat capacity Cr is determined as the initial roasting degree of the coffee beans being roasted.
It can be seen in the above embodiments, the heating time t is predefined. In some alternative embodiments, it is also possible to predefine the amount of temperature change (ΔT) instead of the heating time t. Accordingly, what is measured at step S202 is the time period t elapsed upon the temperature of the coffee beans reaching the target temperature Tm=T0+ΔT, rather than the target temperature Tm. That is, in such embodiments, the term ΔT in equation (3) is known and the term t in equation (2) is measured at step S202.
Generally speaking, in the embodiments discussed with reference to
In the testing phase, associations between different initial roasting degree of the reference coffee beans and respective reference information are determined and recorded, each piece of the reference information indicating the temperature change of the associated reference coffee beans while the associated reference coffee beans are roasted. Then such predetermined associations may be used to identify the initial status of any given coffee beans.
To be specific, as shown in
Next, at step S303, depending on the form of the predetermined associations of the reference coffee beans, information indicating the temperature change of the coffee beans while the coffee beans are roasted is measured. Then, the initial roasting degree of the coffee beans is identified by comparing the measured information to the reference information in the predetermined associations at step S304.
In particular, in some exemplary embodiments, the reference information in the predetermined associations at least includes reference temperatures of the associated reference coffee beans after the coffee beans are roasted from the predefined initial temperature T0 to a target temperature Tm. That is, in those embodiments, the initial and target temperatures T0 and Tm are predefined. In the testing phase, for each type of the reference coffee beans, the reference time period (denoted as tr) during which the reference coffee beans are roasted from T0 to Tm is measured. The reference time periods tr are then stored in association with the respective initial roasting degree of the reference coffee beans. Specifically, in some exemplary embodiments, there may be a plurality of target temperatures Tm. Accordingly, for each of the target temperatures Tm, the reference time period tr for each type of the reference coffee beans is measured and stored.
As an example, Table 2 shows exemplary associations between the initial roasting degree and the reference information. In this case, the reference information includes reference time period tr (in second) for the reference coffee beans to reach the respective target temperatures Tm from the predefined initial temperature T0 (not shown in the table). In this example, there are four predefined target temperature Tm, namely, 190° C., 210° C., 220° C. and 230° C. In the testing phase, a home coffee roaster is used to roast the coffee beans. In this example, the coffee roaster has a heating plate at the bottom of the roasting chamber, a mixing rod to mix the coffee beans during the roasting, and a temperature sensor inside the roasting chamber which is in contact with the coffee beans to sense the surface temperature of the coffee beans. The voltage and heating power of the coffee roaster are 120 v and 800 w, respectively. The roasting chamber is a cylinder with a diameter of 7 cm and a height of 19 cm.
In operation, the roasting chamber is pre-heated to 230° C. It would be appreciated that as the coffee beans are fed into the roaster chamber, the chamber's temperature will drop down. For each types of A, B and C, the reference coffee beans of 30 grams are fed into the roasting chamber of the coffee roaster. The initial temperature T0 is set as the surface temperature of the reference coffee beans before being fed into the roasting chamber. Normally, the initial temperature is near the room temperature which is around 20° C. in this example. Alternatively, the reference coffee beans may be processed to any specified initial temperature. Then the time period tr used to reach the respective target temperature Tm are measured and recorded, as shown in Table 2. It should be noted that the specific values in this example are merely for the purpose of illustration, without limiting the scope of the present invention.
Accordingly, in such embodiments, the coffee beans with the predefined initial temperature (for example, 20° C. in the example discussed with reference to Table 2) are fed into the roasting chamber. At step S303, the measured information at least includes measured time period t during which the coffee beans in the roasting chamber are roasted from the initial temperature T0 to a selected target temperature(s) Tm. Then, at step S304, the measured time period t is compared with the reference time periods tr for the selected target temperature Tm to find a matching reference time period tr. The initial roasting degree associated with the matching reference time period tr is determined as the initial roasting degree of the coffee beans in consideration.
As an example, it is assumed that the time period t during which the coffee beans are roasted from T0 to a selected target temperature Tm=210° C. is 36.5 seconds. The measured time period t=36.5 is compared with the reference time periods tr for Tm=210° C. in the predetermined associations. It is found that for the selected target temperature Tm=210° C., the measured time period t matches the reference time period tr associated with the reference coffee beans of type A. Accordingly, the initial state of the reference coffee beans of type A is determined as the initial roasting degree of the target coffee beans in the roasting chamber.
Specifically, in some exemplary embodiments, more than one target temperature Tm may be utilized. Accordingly, a plurality of time periods t are measured at step S303 for different target temperatures Tm. At step S304, each of the measured time periods t is compared with the reference time periods tr for the respective target temperature Tm, thereby obtaining a plurality of candidate initial roasting degree. Then the initial roasting degree of the coffee beans may be identified based on those candidate initial roasting degree, for example, by the majority decision. In this way, the initial roasting degree of the coffee beans can be identified more accurately.
Alternatively or additionally, in some exemplary embodiments, the reference information at least includes reference temperatures of the associated reference coffee beans after they are roasted from an initial temperature T0 for a time period t. That is, in such embodiments, the initial temperature T0 and the heating time t are determined in advance. Accordingly, in the testing phase, for each type of the reference coffee beans, the reference temperature (denoted as Tr) of the reference coffee after being roasted from the initial temperature T0 for the predefined time period t is measured. The reference temperatures Tr are then stored in association with the respective initial roasting degree of the reference coffee beans. Specifically, in some exemplary embodiments, there may be a plurality of predefined time periods t. Accordingly, for each of the time periods t, the reference temperature Tr for each type of the reference coffee beans is measured and stored.
In such embodiments, the coffee beans with the predefined initial temperature are fed into the roasting chamber. At step S303, the measured information at least includes measured temperature Tm of the coffee beans after the coffee beans are roasted from the initial temperature T0 for a selected time period(s) t. Then, at step S304, the measured temperature Tm is compared with the reference temperatures Tr for the selected time period t to find a matching reference temperature Tr. The initial roasting degree associated with the matching reference temperature Tr is determined as the initial roasting degree of the coffee beans in consideration.
In some exemplary embodiments, more than one predefined time t may be utilized. Accordingly, a plurality of temperature Tm are measured at step S303 for different time periods t. At step S304, each of the measured temperature Tm is compared with the reference temperatures Tr for the respective time period t, thereby obtaining a plurality of candidate initial roasting degree. Then the initial roasting degree of the coffee beans may be identified based on those candidate initial roasting degree to improve the identification accuracy.
In some exemplary embodiments, the predetermined associations may have an additional dimension of weight. That is, in the testing phase, for the same type of reference beans, it is possible to pre-store the associations between the reference information indicating the temperature changes and the initial roasting degree for different weights. In such embodiments, in method 300, the weight of the coffee beans fed into the coffee roaster is obtained. As discussed above, in accordance with embodiments of the present invention, the weight of the coffee beans may be fixed, received from the user, or measured by a weight sensor. At step S304, the weight of the coffee beans in the coffee roaster may be first used to retrieve corresponding reference information from the predetermined associations for comparison with the measured information obtained at step S303.
In some exemplary embodiments, the measured information includes amount of the temperature change of the coffee beans over a time period. In such embodiments, the apparatus 400 may further comprise: a heat quantity estimating unit configured to estimate quantity of heat applied to the coffee beans within the time period; a weight obtaining unit configured to obtain weight of the coffee beans; and a heat capacity calculating unit configured to calculate heat capacity of the coffee beans based on the amount of the temperature change, the quantity of heat and the weight of the coffee beans.
In some exemplary embodiments, the identifying unit 401 is configured to identify the initial roasting degree of the coffee beans at least partially based on the measured information, according to predetermined associations between different initial roasting degree of reference coffee beans and respective reference information, the reference information indicating temperature changes of the associated reference coffee beans while the associated reference coffee beans are roasted.
Specifically, in some exemplary embodiments, the measured information includes a measured temperature of the coffee beans after the coffee beans are roasted from an initial temperature for a predefined time period, and the reference information includes reference temperatures of the associated reference coffee beans after the associated reference coffee beans are roasted from the initial temperature for the predefined time period. In such embodiments, the identifying unit 401 is configured to identify the initial roasting degree of the coffee beans by matching the measured temperature and the reference temperatures.
Alternatively or additionally, in some exemplary embodiments, the measured information includes a measured time period during which the coffee beans are roasted from an initial temperature to a predefined temperature, and the reference information includes reference time periods during which the associated reference coffee beans are roasted from the initial temperature to the predefined temperature. In such embodiments, the identifying unit 401 is configured to identify the initial roasting degree of the coffee beans by matching the measured time period and the reference time periods.
In some exemplary embodiments, the apparatus 400 may comprise a chamber heating unit configured to heat a roasting chamber to be used for roasting the coffee beans for measuring the information indicating the temperature change of the coffee beans.
It should be noted that the apparatus 400 may be implemented as hardware, software/firmware, or any combination thereof. In some embodiments, one or more units in the apparatus 400 may be implemented as software modules. For example, embodiments of the present invention may be embodied as a computer program product that is tangibly stored on a non-transient computer-readable medium. The computer program product comprises machine executable instructions which, when executed, cause the machine to perform steps of any of the methods 100, 200 and 300. Alternatively or additionally, some or all of the units in the apparatus 400 may be implemented using hardware modules like integrated circuits (ICs), application specific integrated circuits (ASICs), system-on-chip (SOCs), field programmable gate arrays (FPGAs), and so on forth.
Moreover, in some exemplary embodiments, the apparatus 400 may be integrated with the coffee roaster. As an example,
Specifically, in accordance with embodiments of the present invention, the apparatus 400 is integrated with the coffee chamber 500. For example, in some embodiments, a temperature sensor 501 is arranged in the roasting chamber 16 to measure the temperature of the coffee beans fed into the roasting chamber 16. As discussed above, in some exemplary embodiments, the temperature sensor 501 is a part of the measuring unit 401 in the apparatus 400. Additionally, in this embodiment, the coffee roaster 501 is equipped with a timer (not shown) configured to detect relevant time periods in measuring the temperature change. Optionally, in those embodiments where it is necessary to measure the weight of the coffee beans, the weight obtaining unit of the apparatus 400, in form of a weight sensor 502, is arranged in the coffee roaster. For example, the weight sensor 502 may be also arranged in the roasting chamber 16. It should be noted that the locations of various units of the apparatus 400 in the coffee roaster 500 are just for the purpose of illustration, without limiting the scope of the present invention.
In general, the various exemplary embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of the exemplary embodiments of the present invention are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.
In the context of the present invention, a machine readable medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.
Computer program code for carrying out methods of the present invention may be written in any combination of one or more programming languages. These computer program codes may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor of the computer or other programmable data processing apparatus, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a computer, partly on the computer, as a stand-alone software package, partly on the computer and partly on a remote computer or entirely on the remote computer or server.
Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination.
Various modifications, adaptations to the foregoing exemplary embodiments of this invention may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings. Any and all modifications will still fall within the scope of the non-limiting and exemplary embodiments of this invention. Furthermore, other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these embodiments of the invention pertain having the benefit of the teachings presented in the foregoing descriptions and the drawings.
Therefore, it will be appreciated that the embodiments of the invention are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are used herein, they are used in a generic and descriptive sense only and not for purposes of limitation.
Number | Date | Country | Kind |
---|---|---|---|
PCT/CN2014/076114 | Apr 2014 | CN | national |
14178542.8 | Jul 2014 | EP | regional |
Filing Document | Filing Date | Country | Kind |
---|---|---|---|
PCT/EP2015/057816 | 4/10/2015 | WO | 00 |