Coffee bean roasting device and method

Abstract

To roast coffee beans so as to bring out a desired flavor.SOLUTION: A roasting device D for coffee beans includes: a roasting part 1 for roasting coffee beans; a measurement part 2 which measures a change in volatilization amount of a plurality of flavor components volatilizing from coffee beans to be roasted by the roasting part 1 and acquires measurement results; and an adjustment part 3 for adjusting how to roast by the roasting part 1 on the basis of the measurement results. The measurement results separately show changes in volatilization amount of the plurality of components. The plurality of components include a first component to be a sweet component and a second component to be a bitter component.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an apparatus and method for roasting coffee beans. [Background technology]

[0002] As an example of this type of technology, Patent Document 1 discloses a method for producing coffee beans, which includes a step of measuring an amount of carbon monoxide generated from coffee beans during roasting, a step of confirming the roast level of the coffee beans at the time of measuring the amount of carbon monoxide in a step of roasting the coffee beans, a step of determining a correspondence relationship between the roast level of the coffee beans and the amount of carbon monoxide based on a result of confirming the roast level of the coffee beans, and a step of using the correspondence relationship as an index of roast level when roasting coffee beans of at least a type or lot different from the coffee beans. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6173395 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, one of the purposes of roasting coffee beans is to bring out the desired aroma and flavor of the coffee beans. In conventional coffee bean roasting methods, the change in color of the coffee beans during roasting is often used as a criterion for controlling the roasting. For example, in the method disclosed in Patent Document 1, the correspondence between the amount of carbon monoxide generated from the coffee beans during roasting and the roast level of the coffee beans is used as an index for control, but since the roast level is based on the change in color of the coffee beans, the change in color of the coffee beans is directly related to the criterion for controlling the roasting (see paragraphs 0063 and 0073 of Patent Document 1).

[0005] However, there are many types of flavors that humans can perceive, such as fruity aromas, sweetness, bitterness, etc. For the above reasons, simply using the change in color of coffee beans as a criterion for controlling roasting is not appropriate from the perspective of bringing out the desired flavor and aroma of coffee beans.

[0006] The present disclosure has been made in view of the above points, and has an object to roast coffee beans so as to bring out a desired aroma and flavor. [Means for solving the problem]

[0007] A first aspect of the present disclosure is a coffee bean roasting device comprising: a roasting unit that roasts coffee beans; a measurement unit that measures changes in volatilization amounts of a plurality of components that constitute flavor and aroma components volatilized from the coffee beans roasted in the roasting unit and obtains measurement results; and an adjustment unit that adjusts a roasting method performed by the roasting unit based on the measurement results, wherein the measurement results separately indicate changes in volatilization amounts of the plurality of components.

[0008] In this disclosure, the "change in volatilization amount" of each component refers to the time history of the volatilization amount of each component in the air, and "measuring the change in volatilization amount" means being able to measure whether the volatilization amount at a certain elapsed time t has increased or decreased compared to the volatilization amount at elapsed time 0.

[0009] In this first disclosure, the measurement unit measures the change in the volatilization amount of multiple components that constitute the flavor and aroma components volatilized from the roasted coffee beans, and the adjustment unit adjusts the roasting method based on the measurement results, so that the coffee can be roasted to bring out the desired flavor and aroma. Furthermore, the measurement results show the change in the volatilization amount of the flavor and aroma components that contain multiple components separately for each component, so that the coffee can be roasted to adjust the multiple flavor and aroma components of the roasted coffee beans. As described above, the coffee beans can be roasted to bring out the desired flavor and aroma.

[0010] A second aspect of the present disclosure is a coffee bean roasting device according to the first aspect, wherein the measurement unit has an adsorption film on its surface capable of adsorbing molecules constituting the plurality of components, and the measurement unit measures a change in the volatilization amount of the plurality of components as the molecules contained in the air of the roasting unit are adsorbed by the adsorption film, and the measurement unit has a switching means capable of switching a state around the sensor, the switching means being capable of switching between a first state in which air from the roasting unit flows around the sensor, and a second state in which air from outside the roasting device flows around the sensor.

[0011] In this second aspect, a specific configuration is obtained in which the change in the volatilization amount of the flavor components is measured by a sensor. The measurement unit has a switching means that can switch between a first state in which air from the roasting unit flows around the sensor and a second state in which air outside the roasting device flows around the sensor, so that not only can the measurement of the change in the volatilization amount of the flavor components be performed in the first state, but also, if necessary, normal air outside the roasting device can be introduced in the second state to return the state around the sensor to the state before measurement. Then, even if an accurate measurement is no longer possible due to too many molecules being adsorbed on the adsorption film of the sensor or the moisture content of the adsorption film fluctuating, the sensor state can be initialized to accurately measure the volatilization amount of the flavor components.

[0012] A third aspect of the present disclosure is a coffee bean roasting device according to the first or second aspect, wherein the plurality of components include bitter components whose volatilization amount increases accelerated after the crack when the coffee beans are roasted.

[0013] In the third embodiment, the increase in the amount of volatilization of bitter components, the increase in the amount of volatilization of which accelerates after the crack, can be measured. In other words, coffee can be roasted so as to suppress the production of bitter components.

[0014] A fourth aspect of the present disclosure is a method for roasting coffee beans using the roasting device according to the third aspect, the method including a classification step of acquiring, for each component, a change in volatilization amount of the plurality of components using the plurality of sensors while roasting the coffee beans, a classification step of acquiring, for each component, a change in volatilization amount of the plurality of components using the plurality of sensors while roasting the coffee beans, and classifying the acquired plurality of volatilization amount changes by flavor type, and from the plurality of volatilization amount changes classified in the classification step, The method for roasting coffee beans includes an identification step of identifying a bitterness detection sensor from the plurality of sensors that can measure the change in the volatilization amount of the bitterness component by identifying the change in the volatilization amount of the bitterness component; a roasting step of roasting coffee beans after the identification step; a measurement step of measuring the change in the volatilization amount of the bitterness component volatilized from the coffee beans in the roasting step with the bitterness detection sensor to obtain the measurement result including the change in the volatilization amount of the bitterness component; and an adjustment step of adjusting the roasting method in the roasting step based on the measurement result.

[0015] In the fourth aspect, a bitterness detection sensor capable of measuring the change in the volatilization amount of bitter components is selected from among a plurality of sensors, and then a roasting process is carried out. Then, the change in the volatilization amount of each bitterness component volatilized from the coffee beans during the roasting process is measured, and the roasting method can be adjusted based on the measurement results. Therefore, roasting can be performed to bring out the desired aroma and flavor while suppressing the generation of bitter components. Effect of the Invention

[0016] As described above, according to the present disclosure, coffee beans can be roasted to bring out a desired aroma and flavor. [Brief description of the drawings]

[0017] [Figure 1] FIG. 1 is a schematic diagram showing a coffee bean roasting device according to an embodiment. [Diagram 2] 1 is a graph showing the change in the amount of volatilization of flavor components measured in Reference Example 1. [Diagram 3] 1 is a graph showing changes in the amount of volatilization of flavor components measured in Reference Example 2. [Figure 4] 1 is a graph showing changes in the amount of volatilization of flavor components measured in Reference Example 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following description of preferred embodiments of the present disclosure is merely exemplary in nature and is not intended to limit the present invention, its application, or its uses.

[0019] [Embodiment] <Coffee bean roasting equipment> 1 shows a coffee bean roaster D according to an embodiment of the present disclosure. Roasting device D includes a roasting unit 1 that roasts coffee beans, a measuring unit 2 that measures changes in the volatilization amounts of multiple components that constitute flavor and aroma components volatilized from coffee beans roasted in roasting unit 1, and an adjusting unit 3 that adjusts the roasting method performed by roasting unit 1 based on the measurement results of measuring unit 2.

[0020] Hereinafter, the configurations of roasting unit 1, measuring unit 2, and adjusting unit 3 will be specifically described with reference to FIG.

[0021] <Roasting Department> The roasting section 1 has a roasting container 11 for accommodating coffee beans. For industrial use, the roasting container 11 is large enough to accommodate, for example, 5 to 80 kg of coffee beans, and for home use, the roasting container 11 is large enough to accommodate, for example, 0.05 to 1 kg of coffee beans. The roasting container 11 is configured to be rotatable in order to mix the coffee beans. The rotation speed of the roasting container 11 is, for example, 30 to 120 rpm.

[0022] Moreover, roasting section 1 has a heat source 12 for supplying heat to the coffee beans contained in roasting container 11. Heat source 12 is, for example, a gas burner. The temperature of the air heated by the heat supplied by heat source 12 is, for example, 100 to 300°C.

[0023] Moreover, roasting section 1 has air blowing section 13 that blows air heated by heat supplied from heat source 12 to the coffee beans contained in roasting container 11. Air blowing section 13 is, for example, a compressor (blower). The amount of air blown by air blowing section 13 per 1 kg of coffee beans is, for example, 0.1 to 1 m per minute. 3 It is.

[0024] In addition, the roasting section 1 communicates with an exhaust passage 14a through which the air blown from the blowing section 13 passes through the inside of the roasting container 11 and is discharged to the outside of the roasting device D, and a measurement passage 14b through which the air flows into the measurement section 2 (hereinafter, when expressing the positions of the exhaust passage 14a and the measurement passage 14b, the side closer to the roasting container 11 is referred to as the "upstream side", and the side farther from the roasting container 11 is referred to as the "downstream side"). In the exhaust passage 14a, a temperature measuring section 15 is provided for measuring the temperature of the air discharged from the roasting container 11 in order to know the atmospheric temperature inside the roasting container 11. In addition, in the middle of the exhaust passage 14a, downstream of the temperature measuring section 15, a chaff collector 16 is provided for collecting chaff (so-called silver skin) of coffee beans. The chaff collector 16 is provided with an afterburner 17 for burning and removing the collected chaff.

[0025] In addition, roasting unit 1 is provided with control unit 18 that adjusts the roasting conditions for coffee beans to control roasting. Control unit 18 controls roasting by appropriately adjusting the roasting conditions and ending roasting, for example, in response to instructions from adjustment unit 3, as described below.

[0026] <Measurement part> The measurement unit 2 has a filter 21 provided in the middle of the measurement passage 14b. The filter 21 is for removing foreign matter such as chaff from the air that flows into the measurement passage 14b from the roasting container 11. The filter 21 is, for example, a ceramic filter that is resistant to high temperatures.

[0027] The measurement unit 2 also has a cooling device 22 provided in the measurement passage 14b downstream of the filter 21. The cooling device 22 is capable of cooling the air passing through the measurement passage 14b, for example, to room temperature.

[0028] Furthermore, measurement unit 2 has air valve 23 (switching means) provided in measurement passage 14b, downstream of cooling device 22. Air valve 23 is configured to be able to switch the air flowing downstream between a first state in which air from roasting container 11 flows through measurement passage 14b to the downstream side of air valve 23, and a second state in which clean air outside roasting device D flows downstream of air valve 23.

[0029] The measurement unit 2 also has a gas pump 24 provided in the middle of the measurement passage 14b downstream of the air valve 23. The gas pump 24 is configured to be able to adjust the amount of air flowing downstream by appropriately blowing air downstream.

[0030] The measuring section 2 also has a plurality of sensors 25 downstream of the gas pump 24, which measure the change in the volatilization amount of flavor components in the air flowing in from the roasting section 1. The plurality of sensors 25 can measure different components. The plurality of sensors 25 have an adsorption film on the surface that can adsorb specific molecules that constitute the flavor components. The plurality of sensors 25 can adsorb different types of specific molecules with their respective adsorption films (hereinafter, in the description of this embodiment, "multiple sensors" will be simply referred to as "sensors"). Since a specific voltage is always applied to the sensor 25, the sensor 25 vibrates at a specific vibration frequency corresponding to the specific voltage. When a molecule is adsorbed on the adsorption film, the sensor 25 changes the vibration frequency in response to the adsorbed molecular weight, and outputs a voltage signal α with an intensity corresponding to the change in the vibration frequency. The "adsorbed molecular weight" here is, strictly speaking, the difference between the weight of the molecule adsorbed on the adsorption film and the weight of the molecule released from the adsorption film, and is correlated with the molecular concentration in the air, that is, the amount of volatilization. That is, the intensity of the voltage signal α is determined according to the amount of volatilization of the adsorbable molecules in the air, and the amount of volatilization of the adsorbable molecules can be determined from the intensity of this voltage signal α. In this way, sensor 25 is configured to measure the amount of volatilization of molecules contained in the air that flows in from roasting section 1 through measurement passage 14b. Then, by measuring the change in the voltage signal α of sensor 25, the change in the amount of volatilization of molecules can be determined. A more specific measurement of the change in the amount of volatilization will be described later as an explanation of the measurement step in the roasting method.

[0031] The multiple flavor and aroma components that the sensor 25 can measure include a first component and a second component that has a different composition from the first component (i.e., at least one of the types of constituent molecules and the content rate of the constituent molecules is different). In this embodiment, the first component is a sweet component that starts to increase in volatilization amount prior to other components when the coffee beans are roasted, and the second component is a bitter component whose increase in volatilization amount accelerates after cracking when the coffee beans are roasted. Here, "crack" refers to a cracking sound that occurs during roasting of the coffee beans. In addition, "the increase in volatilization amount accelerates" means that the rate of increase in the volatilization amount becomes even faster. In other words, the rate of increase in the volatilization amount of the second component, which is a bitter component, becomes faster after cracking compared to before cracking.

[0032] The aforementioned measurement results indicate the time history of the volatilization amount (volatilization amount at each time point since the start of roasting) of the flavor components whose volatilization amount change is measured, specifically, the time history of the volatilization amount of the first component and the second component separately. Note that the measurement results may additionally indicate information at the time of measurement (e.g., temperature inside the roasting container, air temperature, etc.).

[0033] In addition, in case the pressure around the sensor 25 increases due to the air blown by the gas pump 24, an exhaust section (not shown) that can exhaust air to the outside may be provided around the sensor 25 so that the pressure around the sensor 25 can be kept constant.

[0034] <Adjustment section> Adjustment unit 3 receives data on the measurement results from measurement unit 2, and instructs control unit 18 of roasting unit 1 to adjust the roasting method as appropriate based on the measurement results. This allows adjustment of the roasting method by roasting unit 1. The specific adjustment method will be described later as an explanation of the adjustment steps in the roasting method.

[0035] The adjustment unit 3 includes a computer 31 for recording data on the measurement results.

[0036] <How to roast coffee beans> The coffee bean roasting method is a method of roasting coffee beans using the above-mentioned roasting device D. That is, the coffee bean roasting method includes a roasting step of roasting coffee beans, a measuring step of measuring the volatilization amounts of a plurality of flavor and aroma components volatilized from the coffee beans roasted in the roasting step to obtain measurement results, and an adjusting step of adjusting the roasting method based on the measurement results of the measuring step. Each step will be described below.

[0037] <Roasting process> Coffee beans are roasted by the above-mentioned roasting unit 1. Specifically, the roasting process is a process of roasting coffee beans by a so-called hot air method in which air heated by heat source 12 is blown by blowing unit 13 to supply heat to coffee beans in roasting container 11. The roasting time is determined according to the capacity of the roasting container and the set values ​​of the type and volatilization amount of the aroma and flavor components to be measured, and is, for example, 300 to 4800 seconds. The roasting container may be rotated during roasting. Also, the temperature inside roasting container 11 may be confirmed during roasting using temperature measuring unit 15.

[0038] The type of coffee beans used is not particularly limited, and may be, for example, any of Arabica, Robusta, Liberica, and Arabusta. The origin of the coffee beans is also not particularly limited, and may be, for example, any of Ethiopia, Kona, Java, Brazil, Ethiopia, Costa Rica, Kilimanjaro, Vietnam, Colombia, Tanzania, Mocha, Blue Mountain, Crystal Mountain, Kenya, Mandheling, and Mexico. The coffee beans may be used alone or in combination of two or more types. The coffee beans may be decaffeinated.

[0039] In the roasting process, in order to remove chaff from the coffee beans while roasting, the chaff generated by roasting may be collected by a chaff collector 16, or the chaff may be burned and removed by an afterburner 17.

[0040] <Measurement process> The volatilization amount of a plurality of flavor components is measured by the measuring unit 2 described above. The measurement of the volatilization amount may be performed continuously without interruption after the start of roasting, or may be performed intermittently with interruptions. When performing the measurement intermittently with interruptions, clean air is allowed to flow into the vicinity of the sensor 25 by the air valve 23 as necessary when no measurement is being performed. Note that, when the adsorption film of the sensor 25 is hydrophilic, it is preferable to make the above-mentioned clean air contain or be saturated with water vapor in order to prevent measurement errors caused by fluctuations in the amount of moisture in the adsorption film affecting the voltage signal α.

[0041] For a predetermined time (e.g., 100 seconds) after the start of roasting, the moisture contained in the coffee beans turns into water vapor, so the measurement of the amount of volatilization of the flavor and aroma components is not stable. In addition, since the moisture turns into water vapor through an endothermic reaction, the temperature inside the roasting container 11 remains at about 100°C during the predetermined time. For this reason, it is preferable to set the point at which the temperature inside the roasting container starts to rise after the predetermined time as the start point of the measurement of the flavor and aroma components. In addition, it is preferable to take the average value {α(0)} of each voltage signal of the sensor 25 for a predetermined time (e.g., 10 seconds) immediately after the start of measurement, and divide the voltage signal α obtained thereafter by the average value {α(0)}, α / {α(0)}, as the reference value for adjusting the roasting method. The reason for this is that the voltage signal immediately after the start of measurement contains information that depends on the initial state of the sensor 25, and such information becomes a bias for adjusting the roasting method, so that such a factor that causes a measurement error must be removed. Hereinafter, α / {α(0)} is referred to as the reference value β for adjusting the roasting method. This reference value β is considered to be approximately proportional to the magnitude of the volatilization amount of the flavor component measured by the sensor 25, and indicates the change in the volatilization amount of the flavor component.

[0042] <Adjustment process> The roasting method in the roasting section 1 is adjusted by the adjustment section 3 described above.

[0043] Specifically, adjustment unit 3 receives data on the measurement results from measurement unit 2 (i.e., the time history of the aforementioned reference value β), and instructs control unit 18 of roasting unit 1 to adjust the roasting method as appropriate based on the measurement results. Adjustments to the roasting method include, for example, adjusting the amount of heat from heat source 12 (for example, increasing or decreasing the amount of heat supplied, or stopping it), adjusting the amount of air blown by air blower unit 13, and adjusting the rotation speed of roasting container 11.

[0044] For example, the adjustment unit 3 sets a threshold value c for a reference value β that represents the change in the volatilization amount of flavor components measured by the sensor 25, and when the reference value β shown in the measurement result reaches the threshold c, it instructs the control unit 18 to adjust the roasting method.

[0045] <Action and Effects> In this embodiment, the measurement unit 2 measures the amount of evaporation of multiple flavor and aroma components volatilizing from the coffee beans being roasted, and the adjustment unit 3 adjusts the roasting method based on the measurement results, so that the roasting can be performed to bring out the desired flavor and aroma. Furthermore, the measurement results show the time history of the amount of evaporation of the flavor and aroma components containing multiple components separately for each component, so that the roasting can be controlled to adjust the multiple flavor and aroma components of the coffee beans being roasted. As described above, the coffee beans can be roasted to bring out the desired flavor and aroma.

[0046] Incidentally, as shown in Reference Examples 1 to 3 described below, the change in color of coffee beans during roasting differs depending on the type of coffee beans, and the amount of volatilization of each component that constitutes the flavor and aroma components during roasting also differs depending on the type of coffee beans.

[0047] Here, in this embodiment, the amount of evaporation of multiple aroma and flavor components volatilizing from the roasted coffee beans is measured, and the roasting method is adjusted by the adjustment unit 3 based on the measurement results, so that regardless of the type of coffee beans, the beans can be roasted in a way that consistently brings out the desired aroma and flavor.

[0048] Conventionally, when roasting coffee beans, the person roasting the beans (hereinafter referred to as the "operator") often judges whether the roasting is complete based on the color of the coffee beans that changes during the roasting process. When adjusting the roasting method based on the operator's judgment, if the operator's skill is insufficient, there is a risk that the roasting will not be performed accurately.

[0049] In this embodiment, the roasting method is adjusted by the adjustment unit 3 based on the above measurement results, so that roasting can be performed stably to bring out the desired aroma and flavor regardless of the operator's skill.

[0050] Incidentally, the sensor 25 outputs a voltage signal α corresponding to the amount of volatilization of flavor components from a specific vibration frequency corresponding to the weight of molecules adsorbed on the adsorption film. However, if the adsorption film is hydrophilic, the fluctuation in the amount of moisture in the air may affect the vibration frequency and thus the output voltage signal α. In other words, if the amount of moisture in the air fluctuates, the amount of volatilization of the components that constitute the flavor components may not be measured accurately. For example, since the air flowing from the roasting section 1 is generally dry due to roasting, the amount of moisture contained in the adsorption film decreases as the roasting time passes. Then, the vibration frequency also changes accordingly, but such a change in the vibration frequency (and the corresponding change in the voltage signal α) may cause measurement errors in the measurement of the change in the amount of volatilization of flavor components, and therefore, accurate measurement may not be possible. In addition, if too many molecules are adsorbed on the adsorption film of the sensor 25, accurate measurement may not be possible.

[0051] Here, in this embodiment, measurement unit 2 has air valve 23 that can be switched between a first state in which air from roasting unit 1 flows around sensor 25, and a second state in which air from outside roasting device D flows around sensor 25, so that normal air from outside roasting device D can be allowed to flow in in the second state as necessary to initialize the state around sensor 25, allowing intermittent measurement of flavor components by sensor 25. Then, even if the amount of volatilization of flavor components cannot be accurately measured due to fluctuations in the moisture content in the adsorption film or excessive adsorption of molecules to the adsorption film of sensor 25, the state of sensor 25 can be initialized to accurately measure the amount of volatilization of flavor components.

[0052] In addition, in this embodiment, it is possible to measure the amount of volatilization of bitter components, the increase in the amount of volatilization of which accelerates after the crack, i.e., it is possible to roast coffee in a manner that suppresses the production of bitter components.

[0053] Furthermore, in this embodiment, the measurement unit 2 has a gas pump 24 upstream of the sensor 25, and the gas pump 24 can appropriately blow air toward the sensor 25 to stabilize the pressure around the sensor 25, so that the sensor 25 can stably measure the change in the volatilization amount of the flavor components.

[0054] [Modifications of the embodiment] Incidentally, there are many types of flavors that humans can sense, such as fruity aromas, sweetness, bitterness, etc. For this reason, there may be cases where it is desired to understand what types of flavor components humans can sense correspond to components whose volatilization amount can be measured by each of the multiple sensors 25. In other words, there may be cases where it is desired to associate components whose volatilization amount can be measured by each of the multiple sensors 25 with what flavors humans perceive those components to be.

[0055] In consideration of the above, in the roasting method according to the modified embodiment, the components whose volatilization changes can be measured by each of the multiple sensors 25 are associated with flavors and aromas sensed by humans, and then the roasting method according to the above embodiment is carried out. The following describes the roasting method according to this modified embodiment, but explanations of parts common to the above embodiment will be omitted.

[0056] In the roasting method according to this modified example, first, while roasting coffee beans, a classification step is performed in which changes in volatilization amount of a plurality of components are obtained for each component by the plurality of sensors 25, and the obtained plurality of volatilization amount changes are classified by flavor type. The method of classifying the plurality of volatilization amount changes may be, for example, a method using a learning device that has previously machine-learned the relationship between the pattern of volatilization amount change and specific flavor components, or may be a statistical analysis including principal component analysis.

[0057] It should be noted that the multiple sensors 25 are capable of detecting different components, but in this modified example, it may be unclear what specific components the sensors can detect.

[0058] Next, an identification process is performed in which the time histories of the volatilization amounts of the first component (sweet component) and the second component (bitter component) are identified from the time histories of each component obtained in the classification process described above, and a first sensor (sweetness detection sensor) and a second sensor (bitterness detection sensor) that can measure the changes in the volatilization amounts of the first component and the second component, respectively, are identified from the multiple sensors 25.

[0059] Next, the roasting step, the measuring step, and the adjusting step are performed in the same manner as in the manufacturing method according to the above-described embodiment.

[0060] In this modification, a roasting process is performed after identifying a first sensor (sweetness detection sensor) and a second sensor (bitterness detection sensor) that can measure the change in the volatilization amount of a first component (sweetness component) and a second component (bitterness component) from among a plurality of sensors 25. Then, the change in the volatilization amount of the first component and the second component that volatilize from the coffee beans during the roasting process is measured, and the roasting method can be adjusted based on the measurement results. Therefore, roasting can be performed to bring out the desired aroma and flavor while suppressing the bitterness components.

[0061] Furthermore, in this modified example, the sensors 25 capable of measuring the first component and the second component are each identified, so that even if it is unknown which components can measure the change in volatilization amount with each of the multiple sensors 25, coffee can be roasted to bring out the desired aroma and flavor.

[0062] [Other embodiments] In the roasting device D according to the above embodiment, the roasting unit 1 only needs to be able to roast coffee beans. For example, direct-fire roasting may be performed in which the coffee beans are directly heated, in which case the blower unit 13 is not necessary. The measuring unit 2 only needs to be able to measure the amount of volatilization of flavor and aroma components, and it only needs to have at least the sensor 25. The measuring unit 2 is configured independently of the roasting unit 1 via the measurement passage 14b, but the measuring unit 2 may be configured integrally with the roasting unit 1, for example, it may be incorporated inside the roasting unit 1. With this configuration, if the distance between the coffee beans to be roasted and the sensor 25 of the measuring unit 2 is reduced, the time difference between roasting and the measurement of the amount of volatilization of flavor and aroma components is reduced, enabling more accurate control of the roasting.

[0063] Furthermore, in the above embodiment, the measurement results by the measurement unit 2 separately show the changes in the volatilization amount of the first component as a sweet component and the second component as a bitter component, but the measurement results are not limited to this and may be any that separately show the time history of the volatilization amount of multiple components.

[0064] In the above embodiment, the sensor 25 is provided in a plurality of types, but a single sensor may be used. In addition, the sensor 25 changes its vibration frequency when molecules are adsorbed to the adsorption film, but is not limited thereto and may be capable of measuring the change in the amount of volatilization of flavor components.

[0065] In addition, in the above embodiment, the change in the volatilization amount of flavor and aroma components is used as a criterion for controlling roasting, but the color of the coffee beans may also be added as a criterion.

[0066] Furthermore, in the above embodiment, when the reference value β indicated in the measurement result reaches a preset threshold value c, the adjustment unit 3 instructs the control unit 18 to adjust the roasting method, but instead of or in addition to this, the following may be done. That is, at an elapsed time t after the start of measurement, the adjustment unit 3 predicts the reference value β(t+Δt) at time t+Δt based on the change in the reference value (β(0)-β(t)) from elapsed time 0 to t, and issues an instruction to adjust the roasting method. For example, if the reference value β is for a flavor component whose volatilization amount monotonically increases or decreases after the start of measurement, the reference value β(t+Δt) at time t+Δt can be easily predicted at time t. EXAMPLES

[0067] Below, in order to demonstrate the usefulness of the coffee roasting apparatus D and roasting method according to the present disclosure, reference examples 1 to 3 will be described in which coffee beans were actually roasted and evaluated. As described above, the roasting apparatus D and roasting method according to the present disclosure are based on the change in the volatilization amount of the first component and the second component in order to adjust the roasting, whereas reference examples 1 to 3 are based on the change in the volatilization amount of only the second component. Moreover, the roasting apparatus and roasting method used in reference examples 1 to 3 are the same as each other, except that the roasted coffee beans are produced in different places.

[0068] <Preparing the roasting equipment> The configuration of the roasting device used was the same as that described in the above embodiment, except for the adjustment unit. Specific product names, etc. are as follows.

[0069] The filter used was Isofil (registered trademark) IV manufactured by Isolite Kogyo Co., Ltd. The roasting section used an industrial roasting furnace (model number R60ROA) manufactured by Gotthot Co., Ltd. A gas burner was used as the heat source, and a blower was used as the air blowing section.

[0070] As the sensors, 180 pieces of nose@MEMS (registered trademark) manufactured by I-PEX Corporation were used. In other words, the 180 sensors used can measure the change in the volatilization amount of a total of 180 types of molecules. As the gas pump, the above-mentioned accessory of nose@MEMS (registered trademark) was used. The capacity of the gas pump was stable at 100 mL / min.

[0071] <Classification process and identification process> Since the molecules capable of measuring the change in volatilization amount were unknown for the 180 sensors described above, the classification process and identification process described in the description of the modified example were carried out. That is, the patterns of change in the voltage signals of the 180 sensors during roasting were classified, and six types (patterns 1 to 6) that are particularly related to the aroma component x of coffee beans (hereinafter, the aroma component of coffee beans will be referred to as x) were identified from the classified patterns, and sensors A to F whose time changes in the obtained reference value βx are similar to these patterns 1 to 6 were identified. An explanation of these patterns 1 to 6 is shown in Table 1.

[0072] [Table 1]

[0073] The changes in the voltage signal corresponding to the change in the volatilization amount of the flavor component (first component) that increases before the other components are patterns 2 and 4, and the first sensors capable of measuring the change in the volatilization amount of this first component are sensors B and D. The changes in the voltage signal corresponding to the change in the volatilization amount of the flavor component (second component) that increases after the breakthrough are pattern 3, and the second sensor capable of measuring the change in the volatilization amount of this second component is sensor C.

[0074] <Roasting process and measurement process> Arabica coffee beans were roasted in amounts of 60 kg each from Colombia (Reference Example 1), Brazil (Reference Example 2), and Ethiopia (Reference Example 3). The point at which the temperature inside the roasting container started to rise after the start of roasting was taken as the start point of measurement of the aroma and flavor components. Data on the voltage signal αx for the aroma and flavor component x was received from sensors A to F. The average value {αx(0)} of the voltage signal for 10 seconds immediately after the start of measurement was calculated, and then αx / {αx(0)}, which was obtained by dividing the obtained voltage signal αx by {αx(0)}, was taken as the reference value βx of the aroma and flavor component x.

[0075] The changes in the reference value βx (corresponding to the change in the volatilization amount of the second component) measured in Reference Examples 1 to 3, which were obtained from the sensor C capable of measuring the change in the volatilization amount of the second component (bitter component), are shown in Figure 2 (Reference Example 1), Figure 3 (Reference Example 2), and Figure 4 (Reference Example 3), respectively. In the graphs of Figures 2 to 4, the vertical axis indicates the reference value βx of the second component x, and the horizontal axis indicates the measurement time of the flavor component x, with the measurement start time being set to 0.

[0076] <Adjustment process> The adjustment unit 3 is configured to stop the supply of heat to the coffee beans by the roasting unit 1, terminate the roasting, and stop the gas pump when the reference value βx obtained from the sensor C exceeds a preset threshold value cx for three seconds or more.

[0077] (Comparison of roasting results and sensory test) A sensory test was conducted using the sense of smell of five people, and the results were compared with the roasting results of Reference Examples 1 to 3.

[0078] In the above-mentioned measurement process, when the reference value βx of the flavor and aroma components measured by sensor C reached 1.1, 1.2, and 1.3, 100 g samples of coffee beans being roasted were taken from the roasting furnace and used as samples for evaluation. Hereinafter, the samples of Reference Example 1 (produced in Colombia) will be represented as C1, C2, and C3 in the order in which they were taken. Similarly, the samples of Reference Example 2 (produced in Brazil) and Reference Example 3 (produced in Ethiopia) will be represented as B1, B2, and B3, and E1, E2, and E3, respectively, in the order in which they were taken. Note that Figures 2 to 4 show the time points at which these samples were taken.

[0079] The sampled coffee beans were each crushed into powder, and a sensory test was conducted in which five people smelled the compressed coffee beans. The results of the sensory test are shown in Table 2 below. Note that the sensory test results shown in Table 2 are the results of the most consistent evaluations among the opinions of the five people who conducted the sensory test.

[0080] [Table 2]

[0081] Although the results of the sensory test differed depending on the type of coffee beans (place of origin) and the degree of roasting (the magnitude of the reference value βx), in all of Reference Examples 1 to 3, when the reference value βx (indicating the change in the volatilization amount of the second component) measured by Sensor C reached 1.3, a burnt odor was sensed (see C3, B3, and E3 in Table 2). This shows that the generation of a burnt odor can be suppressed by ending the roasting before the reference value βx reaches 1.3, regardless of the type of coffee beans.

[0082] (Check the color of coffee beans) The colors of the coffee beans roasted in Reference Examples 1 to 3 were confirmed as follows.

[0083] As mentioned above, the coffee beans collected as samples were ground into powder and compressed, and their color was measured using a Lightells kit (model number CM-100) and used as a reference. The color of the ground coffee beans in the powdered and compressed state was compared with the color sample of the measurement scale standard of the Specialty Coffee Association of America (SCAA) shown in Table 3 below.

[0084] [Table 3]

[0085] The color evaluation results for the coffee bean samples are shown in Table 4 below. Note that the values ​​in the "SCAA value of sample" section in Table 4 are the results of comparing with the SCAA standard color samples in Table 3.

[0086] [Table 4]

[0087] According to Table 4, when comparing the roasting times of the samples roasted in Reference Example 1 and Reference Example 2 with the same reference value βx, there are differences in that C1 is 70 seconds shorter than B1, C2 is 90 seconds shorter than B2, and C3 is 120 seconds shorter than B3. Despite these differences in roasting times, the color matching results for C1 (74) and B1 (75), C2 (55) and B2 (56), and C3 (35) and B3 (35) show almost the same values, and there is no significant difference in color between Reference Example 1 and Reference Example 2.

[0088] On the other hand, in Table 4, when the roasting times of the samples roasted in Reference Example 1 and Reference Example 3 are compared with each other, which show the same βx, there are only slight differences, that is, C1 is the same as E1, C2 is 10 seconds shorter than E2, and C3 is 10 seconds shorter than E3. However, the color matching results were C1 (74) and E1 (80), C2 (55) and E2 (61), and C3 (35) and E3 (38), and overall Reference Example 1 had a smaller SCAA value and a darker color than Reference Example 3. And, the difference in the respective SCAA values ​​is larger when comparing Reference Example 1 and Reference Example 3 than when comparing Reference Example 1 and Reference Example 2.

[0089] The results shown in Table 4 described above reveal the following. First, in a comparison between Reference Example 1 and Reference Example 2, the roasting time is significantly different between the same βx, but the difference in color is relatively small. In contrast, in a comparison between Reference Example 1 and Reference Example 3, the roasting time is small between the same βx, but the difference in color is relatively large. That is, the roasting level determined from the reference value βx may differ from the change in color of the coffee beans, and may also differ from the roasting level determined from the roasting time. For this reason, it can be seen that even if the roasting method is adjusted using either the change in color of the coffee beans or the roasting time as the criterion for determining the roasting level, the desired flavor and aroma components may not be extracted. In contrast, the manufacturing apparatus and manufacturing method according to the present disclosure, which adjusts the roasting method using the change in the volatilization amount of the flavor and aroma components as a reference value, are excellent in that the volatilization amount of the flavor and aroma components is directly measured, and therefore the desired flavor and aroma components can be extracted.

[0090] (Measurement of changes in volatilization of multiple flavor components) Tables 5 to 7 show the changes in each reference value β obtained by sensors A to F during roasting in Reference Examples 1 to 3. Table 5 shows the results of each reference value βx obtained by sensors A to F during roasting in Reference Example 1 (Colombian).

[0091] [Table 5]

[0092] Table 6 shows the results of each reference value βx obtained by sensors A to F in roasting of Reference Example 2 (produced in Brazil).

[0093] [Table 6]

[0094] Table 7 shows the results of each reference value βx obtained by sensors A to F in roasting of Reference Example 3 (produced in Ethiopia).

[0095] [Table 7]

[0096] As shown in Tables 5 to 7, the standard value βx of the aroma and flavor components volatilized from coffee beans by roasting shows different patterns depending on the type of coffee beans. In other words, the roasting device and roasting method according to the present disclosure, which measures the change in the volatilization amount of multiple aroma and flavor components and adjusts the roasting method using multiple corresponding standard values ​​as judgment criteria, can be said to be particularly useful when it is desired to bring out subtle aromas in the roasting of coffee beans. [Explanation of symbols]

[0097] D. Roasting Equipment 1. Roasting Department 2 Measuring part 3 Adjustment part 11 Roasting container 12 Heat source 13 Blower section 14a Exhaust passage 14b Measurement passage 15 Temperature measurement section 16 Chaff Collector 17. Afterburner 18 Control Unit 21 Filters 22 Cooling device 23 Air valve (switching means) 24 Gas Pump 25 Sensors (multiple sensors) 31 Computer

Claims

1. A roasting section for roasting coffee beans; a measurement unit that measures changes in the volatilization amounts of a plurality of components that constitute flavor and aroma components volatilized from the coffee beans roasted in the roasting unit and acquires measurement results; an adjustment unit that adjusts the roasting method of the roasting unit based on the measurement results; Equipped with The measurement unit has a plurality of sensors, the plurality of sensors have an adsorption film on a surface thereof capable of adsorbing molecules constituting the plurality of components, and the molecules contained in the air in the roasting section are adsorbed onto the adsorption film to measure a change in the amount of volatilization of the plurality of components; the adsorption films of the plurality of sensors are different from each other in the types of specific molecules that can be adsorbed; The measurement results show the volatilization changes of the multiple components separately. Coffee bean roasting equipment.

2. In the roasting apparatus according to claim 1, The coffee bean roasting device, wherein the measurement unit has a switching means capable of switching a state around the sensor, between a first state in which air from the roasting unit flows around the sensor, and a second state in which air outside the roasting device flows around the sensor.

3. A method for roasting coffee beans using the roasting device according to claim 1 or 2, The method for roasting coffee beans, wherein the plurality of components include bitter components whose volatilization amount increases accelerated after the crack when the coffee beans are roasted.

4. 4. The method for roasting coffee beans according to claim 3, a classification step of acquiring a change in volatilization amount of each of the plurality of components by the plurality of sensors while roasting the coffee beans, and classifying the acquired plurality of changes in volatilization amount by flavor type; a step of identifying a bitterness detection sensor capable of measuring the change in the volatilization amount of the bitterness component from among the plurality of the volatilization amount changes classified in the classification step, from among the plurality of sensors; a roasting step of roasting the coffee beans after the identifying step; a measuring step of measuring a change in the amount of volatilization of a bitter component volatilized from coffee beans in the roasting step with the bitterness detection sensor to obtain the measurement result including the change in the amount of volatilization of the bitter component; an adjusting step of adjusting the roasting method in the roasting step based on the measurement results; A method for roasting coffee beans comprising the steps of:

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