Coffee beans with mixed flavor and preparation process thereof

Abstract

The invention relates to the field of coffee beans, and particularly discloses coffee beans with mixed flavor and a preparation process thereof. The invention discloses a preparation process of coffee beans with mixed flavor. The preparation process comprises the following steps: screening raw ESecsian beans and raw Kenila beans, sorting, removing impurities, optimizing color sorting, and pre-treating to obtain washed ESecsian beans, sun-dried ESecsian beans and washed Kenila beans; the coffee beans with mixed flavor are prepared by the following steps: respectively dehydrating ESecRussian water-washed beans and Kenya water-washed beans according to a specific mode, then blending the dehydrated ESecRussian water-washed beans and Kenya water-washed beans with ESecRussian solarized beans according to a weight ratio of (2-3): (4-5.5): (2.5-3), carrying out specific baking heating and heat preservation treatment, and then carrying out air cooling at a certain air speed until the bean temperature is 35 DEG C or below. According to the preparation method, the effect of preparing the coffee beans with the mixed flavor is achieved, and the coffee beans can present a unique flavor through a specific preparation process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coffee beans, in particular to a coffee bean with mixed flavors and a preparation process thereof. BACKGROUND

[0002] Coffee is one of the most widely consumed beverages in the world, and its quality is closely related to the preparation process of coffee beans. At present, the common preparation process of coffee beans on the market mainly includes the steps of screening, water washing / sun drying, roasting, cooling and the like. Impurities in raw beans are removed through screening, and then pretreatment is performed through water washing or sun drying. Roasting makes the raw beans change color and produce appropriate aroma, and cooling obtains roasted coffee beans. Different raw beans have different flavors, and different water washing / sun drying and roasting processes can obtain coffee with different flavors. Some people also propose that different coffee beans can be mixed to provide consumers with products with more harmonious and diverse flavors. However, it is difficult to obtain coffee beans with mixed flavors, and the control of the flavors is always a big problem in the field. SUMMARY

[0003] In order to solve the above technical problems, the present application provides a coffee bean with mixed flavors and a preparation process thereof.

[0004] In a first aspect, the present application provides a preparation process of a coffee bean with mixed flavors, comprising the following steps: S1. Screening: sorting and removing impurities from Ethiopian raw beans and Kenyan raw beans, and then performing color selection optimization; S2. Pretreatment: obtaining Ethiopian water-washed beans, Ethiopian sun-dried beans and Kenyan water-washed beans; S3. Roasting: dehydrating the Ethiopian water-washed beans and the Kenyan water-washed beans, and then blending them with the Ethiopian sun-dried beans, wherein the Ethiopian water-washed beans, the Ethiopian sun-dried beans and the Kenyan water-washed beans are blended in a weight ratio of (2-3):(4-5.5):(2.5-3), and then heated at a heating rate of 8-10℃ / min to 180-196℃, and then heated at a heating rate of 4-5℃ / min to 204-210℃ after holding for 7-9min, and then the roasting is completed; S4. Cooling: air cooling at a wind speed of 8-10m / s to reduce the bean temperature to below 35℃, and obtaining the coffee bean with mixed flavors.

[0005] By adopting the above technical solution, this application first uses a screening step to sort and remove impurities from Ethiopian and Kenyan green beans and optimize color sorting, which can remove impurities and optimize bean quality; the pretreatment yields different types of beans, providing a basis for subsequent blending; the roasting step mixes the three types of beans in a specific weight ratio and roasts them using a specific heating rate and temperature, which enables the coffee beans to form a unique blended flavor; the cooling step uses air cooling at a specific wind speed to lower the bean temperature, which helps to fix the coffee bean flavor, and finally produces coffee beans with a blended flavor.

[0006] Importantly, Ethiopian washed beans have fresh floral and citrus notes, resulting in a very bright acidity that provides a refreshing citrus acidity and floral base. Ethiopian sun-dried beans, on the other hand, offer ripe berry aromas and fermented wine notes. Due to the sun-drying process, they also have a higher sweetness, adding to the berry fermentation feel and sweetness layers. Kenyan washed beans have blackcurrant flavors and a unique phosphoric acidity, with fuller and more uniform grains, bringing bright blackcurrant acidity and a brown sugar finish. Blending these three beans in a certain weight ratio can create a complex and balanced flavor structure.

[0007] Overall, this application improves the purity and quality of coffee beans by sorting, removing impurities, and optimizing the color of Ethiopian and Kenyan green beans. By blending and roasting Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans obtained through different processing methods in a specific weight ratio, coffee beans with a blended flavor can be produced, meeting consumers' demand for diverse flavors. Furthermore, roasting at a specific heating rate and temperature, followed by air cooling at a specific wind speed, helps to form unique flavors and improve the taste and quality of the coffee beans.

[0008] Preferably, in step S3, the dehydration of Ethiopian washed beans specifically includes: Air dry until the moisture content reaches 45-50%, then heat to 50℃ at a rate of 0.8-1℃ / min under conditions of 35-40℃ and 3-4m / s wind speed until the moisture content reaches 10-11%, and optimize color sorting until the color difference value △E < 2.

[0009] Preferably, in step S3, the dehydration of Kenyan washed beans specifically includes: Centrifuge at 1100-1200 rpm for 5-6 min, then dry at 55-60℃ for 12 h, and then dry at 35-40℃ for 36 h until the moisture content reaches 11-12%. Color sorting is then performed until the color difference value ΔE < 2.

[0010] By adopting the above technical solution, the moisture content of Ethiopian washed beans can reach 10-11% and the color difference value ΔE < 2. This ensures the dehydration effect while optimizing the color, guaranteeing the quality and stability of Ethiopian washed beans. Combined with screening, pretreatment, blending with other beans in proportion, roasting at a specific heating rate and air cooling, coffee beans with a blended flavor are finally produced.

[0011] Preferably, in step S3, Ethiopian washed beans and Kenyan washed beans are dehydrated separately and then blended with Ethiopian sun-dried beans in a weight ratio of 2.5:4.7:2.8.

[0012] By adopting the above technical solution, this application screens and pre-processes Ethiopian and Kenyan green beans. After dehydrating Ethiopian washed beans and Kenyan washed beans separately, they are blended with Ethiopian sun-dried beans in a weight ratio of 2.5:4.7:2.8. After roasting and cooling, coffee beans with a unique blended flavor can be obtained. The specific weight ratio helps to achieve a better blending effect of coffee bean flavor.

[0013] Preferably, in step S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are mixed together, heated to 188°C at a heating rate of 9°C / min, held at that temperature for 3 minutes, and then heated to 207-208°C at a heating rate of 4.5°C / min to end the roasting process.

[0014] Preferably, in step S1, color sorting optimization is performed until the color difference value ΔE < 3.

[0015] By adopting the above technical solution, after sorting and removing impurities from Ethiopian and Kenyan green coffee beans, color sorting optimization is carried out until the color difference value ΔE < 3, which can further improve the quality of coffee beans and provide high-quality raw materials for the subsequent preparation of coffee beans with mixed flavors.

[0016] Preferably, in step S2, the Ethiopian raw beans are soaked, peeled and degummed, fermented and degummed, washed, and floated to obtain Ethiopian washed beans.

[0017] Preferably, in step S2, Ethiopian raw beans are exposed to sunlight for 35-42 days, followed by peeling, degumming, and shelling to obtain Ethiopian sun-dried beans.

[0018] Preferably, Kenyan green beans are soaked, peeled and degummed, fermented and degummed, double-washed, and floated to obtain washed Kenyan beans.

[0019] By adopting the above-mentioned technical solutions, this application performs soaking, dehulling and degumming, fermentation and degumming, washing / double washing and flotation treatments on Ethiopian green beans and Kenyan green beans, which can remove impurities and gums from the surface of green beans, improve the purity of coffee beans, and lay a good foundation for the subsequent preparation of coffee beans with blended flavors; exposing Ethiopian washed beans to sunlight can enable the coffee beans to develop the unique flavor of sun-dried beans; subsequent dehulling and degumming and flotation treatments can remove impurities, ensure the purity and quality of coffee beans, and help to produce coffee beans with blended flavors.

[0020] Secondly, this application provides a blended flavor coffee bean prepared by the above-described preparation process.

[0021] In summary, this application includes the following beneficial technical effects: In the screening step, Ethiopian and Kenyan green coffee beans are sorted and impurities are removed to improve their purity. Further color sorting optimization is performed until the color difference value ΔE < 3, selecting coffee beans with more uniform color and better quality, laying the foundation for the subsequent preparation of high-quality blended coffee beans. In the pre-processing stage, Ethiopian green beans are soaked, dehulled, fermented, washed, and floated to obtain Ethiopian washed beans. These washed beans are then sun-dried and dehulled before being floated to obtain Ethiopian sun-dried beans. Kenyan green beans are soaked, dehulled, fermented, washed, and floated to obtain Kenyan washed beans. These different processing methods impart different flavor characteristics to the coffee beans. In the roasting step, Ethiopian and Kenyan washed beans are processed using specific dehydration methods and then blended with Ethiopian sun-dried beans. This specific weight ratio allows the different flavors of the coffee beans to meld together. Staged, specific heating rates and temperature control can stimulate the flavor compounds inside coffee beans, allowing them to fully release their unique aroma and flavor, thus producing coffee beans with a blended flavor to meet consumers' demand for diverse flavors. The cooling step, which rapidly lowers the bean temperature to below 35°C, helps to fix the unique flavors formed during the roasting process, prevents the loss of flavor compounds, and further enhances the taste and quality of the coffee beans. Detailed Implementation

[0022] The present application will be further described in detail below with reference to embodiments and comparative examples.

[0023] A process for preparing coffee beans with a blended flavor includes the following steps: S1. Screening: Ethiopian and Kenyan green beans are sorted and impurities are removed, followed by color sorting optimization; S2. Pre-treatment: to obtain Ethiopian washed beans, Ethiopian sun-dried beans and Kenyan washed beans; S3. Roasting: Dehydrate Ethiopian washed beans and Kenyan washed beans separately, then blend them with Ethiopian sun-dried beans at a weight ratio of (2-3):(4-5.5):(2.5-3). Then, heat the mixture to 180-196℃ at a heating rate of 8-10℃ / min, hold it at that temperature for 7-9 minutes, and then heat it to 204-210℃ at a heating rate of 4-5℃ / min to finish roasting. S4. Cooling: Air cooling is performed at a wind speed of 8-10 m / s to lower the bean temperature to below 35°C, resulting in coffee beans with a blended flavor.

[0024] In a preferred embodiment of this application, the dehydration of Ethiopian washed soybeans in step S3 specifically includes: Air dry until the moisture content reaches 45-50%, then heat to 50℃ at a rate of 0.8-1℃ / min under conditions of 35-40℃ and 3-4m / s wind speed until the moisture content reaches 10-11%, and optimize color sorting until the color difference value △E < 2.

[0025] In a preferred embodiment of this application, the dehydration of Kenyan washed beans in step S3 specifically includes: centrifugation at 1100-1200 rpm for 5-6 min, followed by drying at 55-60°C for 12 h, drying at 35-40°C for 36 h until the moisture content reaches 11-12%, and color sorting optimization until the color difference value ΔE < 2.

[0026] In a preferred embodiment of this application, in step S3, Ethiopian washed beans and Kenyan washed beans are dehydrated and then blended with Ethiopian sun-dried beans in a weight ratio of 2.5:4.7:2.8.

[0027] In a preferred embodiment of this application, in step S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are blended, heated to 188°C at a heating rate of 9°C / min, held at that temperature for 3 minutes, and then heated to 207-208°C at a heating rate of 4.5°C / min to end the roasting process.

[0028] In a preferred embodiment of this application, in step S1, color sorting optimization is performed until the color difference value ΔE < 3.

[0029] In a preferred embodiment of this application, in step S2, Ethiopian raw beans are soaked, peeled and degummed, fermented and degummed, washed, and floated to obtain washed Ethiopian beans.

[0030] In a preferred embodiment of this application, in step S2, Ethiopian raw beans are exposed to sunlight for 35-42 days, followed by peeling, degumming, and shelling to obtain Ethiopian sun-dried beans.

[0031] In a preferred embodiment of this application, Kenyan green beans are soaked, peeled and degummed, fermented and degummed, double-washed, and flotated to obtain washed Kenyan beans.

[0032] Example 1 A process for preparing coffee beans with a blended flavor includes the following steps: S1. Screening: Ethiopian and Kenyan green beans are placed in a vibrating screen for sorting and impurity removal. Then, a CCD color sorter is used to identify and remove moldy and insect-infested beans until the color difference value △E of the beans is less than 3. S2. Preprocessing: S21. Soak the selected Ethiopian green coffee beans in a water tank for 24 hours. Remove unripe, shriveled, and other defective beans that float by density difference, and retain the high-quality beans that sink to the bottom. Then, use a peeling machine to remove the outer skin and most of the pulp of the coffee cherries, put them into a fermentation tank, add an equal amount of water, and let them ferment for 30 hours. Then, rinse the coffee beans thoroughly with water to remove residual pectin and fermentation byproducts. Remove defective beans with uneven density by water flow sorting to ensure that the beans are clean and obtain Ethiopian washed coffee beans. S22. Place the selected Ethiopian green beans into a water tank to separate the floating light impurities by density difference. Then spread the fruits on a drying bed with a thickness of no more than 5cm to avoid mold. Expose them to sunlight for 35 days. Turn the fruits once every hour for the first 7 days, turn them 4 times a day from 7 to 21 days, and stop turning them from 22 to 25 days. Then use a shelling machine to remove the peel, pulp and parchment layer, retaining the silver skin, to obtain Ethiopian sun-dried beans. S23. Soak the selected Kenyan green beans in a water tank for 24 hours. Remove unripe, shriveled, and other defective beans that float by density difference, and keep the high-quality beans that sink to the bottom. Then, use a peeling machine to remove the outer skin and most of the pulp of the coffee cherries, put them into a fermentation tank, add an equal amount of water, and let them ferment for 30 hours. Then rinse the coffee beans with water to remove residual pectin and fermentation byproducts. Remove defective beans with uneven density by water flow sorting to ensure that the beans are clean. Finally, rinse the coffee beans with water to obtain Kenyan washed beans. S3. Baking: Air-dry the Ethiopian washed beans until the moisture content reaches 50%, then heat them to 50°C at a rate of 1°C / min under conditions of 40°C and a wind speed of 3m / s. The moisture content was increased to 11%, and then a CCD color sorter was used to identify and remove moldy and insect-damaged beans until the color difference value ΔE < 2. Kenyan washed beans were centrifuged at 1200 rpm for 5 min, then dried at 60℃ for 12 h and at 35℃ for 36 h until the moisture content reached 12%. Again, a CCD color sorter was used to identify and remove moldy and insect-damaged beans until the color difference value ΔE < 2. Ethiopian washed beans, Ethiopian sun-dried beans and Kenyan washed beans were mixed in a weight ratio of 2:5.5:2.5. The mixture was then heated to 196℃ at a heating rate of 10℃ / min, held at that temperature for 9 min, and then heated to 210℃ at a heating rate of 4℃ / min to end the roasting process. S4. Cooling: Air cooling is performed at a wind speed of 10 m / s to lower the bean temperature to below 35°C, resulting in coffee beans with a blended flavor.

[0033] Example 2 A process for preparing coffee beans with a blended flavor includes the following steps: S1. Screening: Ethiopian and Kenyan green beans are placed in a vibrating screen for sorting and impurity removal. Then, a CCD color sorter is used to identify and remove moldy and insect-infested beans until the color difference value △E of the beans is less than 3. S2. Preprocessing: S21. Soak the selected Ethiopian green coffee beans in a water tank for 24 hours. Remove unripe, shriveled, and other defective beans that float by density difference, and retain the high-quality beans that sink to the bottom. Then, use a peeling machine to remove the outer skin and most of the pulp of the coffee cherries, put them into a fermentation tank, add an equal amount of water, and let them ferment for 30 hours. Then, rinse the coffee beans thoroughly with water to remove residual pectin and fermentation byproducts. Remove defective beans with uneven density by water flow sorting to ensure that the beans are clean and obtain Ethiopian washed coffee beans. S22. Place the selected Ethiopian green beans into a water tank to separate the floating light impurities by density difference. Then spread the fruits on a drying bed with a thickness of no more than 5cm to avoid mold. Expose them to sunlight for 42 days. Turn the fruits once every hour for the first 7 days, turn them 4 times a day from 7 to 21 days, and stop turning them from 22 to 25 days. Then use a shelling machine to remove the skin, pulp and parchment layer, retaining the silver skin, to obtain Ethiopian sun-dried beans. S23. Soak the selected Kenyan green beans in a water tank for 24 hours. Remove unripe, shriveled, and other defective beans that float by density difference, and keep the high-quality beans that sink to the bottom. Then, use a peeling machine to remove the outer skin and most of the pulp of the coffee cherries, put them into a fermentation tank, add an equal amount of water, and let them ferment for 30 hours. Then rinse the coffee beans with water to remove residual pectin and fermentation byproducts. Remove defective beans with uneven density by water flow sorting to ensure that the beans are clean. Finally, rinse the coffee beans with water to obtain Kenyan washed beans. S3. Baking: Air-dry the Ethiopian washed beans until the moisture content reaches 45%, then heat them to 50°C at a rate of 0.8°C / min under conditions of 35°C and 4m / s wind speed. Until the moisture content reaches 10%, a CCD color sorter is used to identify and remove moldy and insect-damaged beans until the color difference value ΔE < 2. Kenyan washed beans are centrifuged at 1100 rpm for 5 min, then dried at 55℃ for 12 h and at 40℃ for 36 h until the moisture content reaches 11%. Again, a CCD color sorter is used to identify and remove moldy and insect-damaged beans until the color difference value ΔE < 2. Ethiopian washed beans, Ethiopian sun-dried beans and Kenyan washed beans are blended in a weight ratio of 3:4:3. The mixture is then heated to 180℃ at a heating rate of 8℃ / min, held at that temperature for 7 min, and then heated to 204℃ at a heating rate of 5℃ / min to finish roasting. S4. Cooling: Air cooling is performed at a wind speed of 8 m / s to lower the bean temperature to below 35°C, resulting in coffee beans with a blended flavor.

[0034] Example 3 A preparation process for coffee beans with a blended flavor differs from that of Example 1 in that, in S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are blended in a weight ratio of 2.9:4.5:2.6, while the rest is the same as in Example 1.

[0035] Example 4 A preparation process for coffee beans with a blended flavor differs from that of Example 1 in that, in S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are blended in a weight ratio of 2.8:4.5:2.7, while the rest is the same as in Example 1.

[0036] Example 5 A preparation process for coffee beans with a blended flavor differs from that of Example 1 in that, in S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are blended in a weight ratio of 2.5:4.7:2.8, while the rest is the same as in Example 1.

[0037] Example 6 A preparation process for coffee beans with a blended flavor differs from that of Example 1 in that, in S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are blended in a weight ratio of 2.2:4.9:2.9, while the rest is the same as in Example 1.

[0038] Comparative Example 1 Includes the following steps: S1. Screening: Ethiopian and Kenyan green beans are placed in a vibrating screen for sorting and impurity removal. Then, a CCD color sorter is used to identify and remove moldy and insect-infested beans until the color difference value △E of the beans is less than 3. S2. Preprocessing: S21. Place the selected Ethiopian green beans into a water tank and separate the floating light impurities by density difference. Then spread the fruits on a drying bed with a thickness of no more than 5cm to avoid mold. Expose them to sunlight for 35 days. Turn the fruits once every hour for the first 7 days, turn them 4 times a day from 7 to 21 days, and stop turning them from 22 to 25 days. Then use a shelling machine to remove the skin, pulp and parchment layer, retaining the silver skin, to obtain Ethiopian sun-dried beans. S22. Soak the selected Kenyan green beans in a water tank for 24 hours. Remove unripe, shriveled, and other defective beans that float by density difference, and keep the high-quality beans that sink to the bottom. Then, use a peeling machine to remove the outer skin and most of the pulp of the coffee cherries, put them into a fermentation tank, add an equal amount of water, and let them ferment for 30 hours. Then rinse the coffee beans with water to remove residual pectin and fermentation byproducts. Remove defective beans with uneven density by water flow sorting to ensure that the beans are clean. Finally, rinse the coffee beans with water to obtain Kenyan washed beans. S3. Roasting: Kenyan washed beans are centrifuged at 1200 rpm for 5 min, then dried at 60℃ for 12 h, and then dried at 35℃ for 36 h until the moisture content reaches 12%. Moldy and insect-damaged beans are then identified and removed using a CCD color sorter until the color difference value ΔE < 2. Ethiopian sun-dried beans and Kenyan washed beans are blended at a weight ratio of 5.5:2.5, then heated to 196℃ at a heating rate of 10℃ / min, held at that temperature for 9 min, and then heated to 210℃ at a heating rate of 4℃ / min to end the roasting process. S4. Cooling: Air cooling is performed at a wind speed of 10 m / s to lower the bean temperature to below 35°C, resulting in coffee beans with a blended flavor.

[0039] Comparative Example 2 Includes the following steps: S1. Screening: Ethiopian raw beans are placed in a vibrating screen to sort and remove impurities, and then a CCD color sorter is used to identify and remove moldy beans and insect-infested beans until the color difference value △E of the beans is less than 3. S2. Preprocessing: S21. Soak the selected Ethiopian green coffee beans in a water tank for 24 hours. Remove unripe, shriveled, and other defective beans that float by density difference, and retain the high-quality beans that sink to the bottom. Then, use a peeling machine to remove the outer skin and most of the pulp of the coffee cherries, put them into a fermentation tank, add an equal amount of water, and let them ferment for 30 hours. Then, rinse the coffee beans thoroughly with water to remove residual pectin and fermentation byproducts. Remove defective beans with uneven density by water flow sorting to ensure that the beans are clean and obtain Ethiopian washed coffee beans. S22. Place the selected Ethiopian green beans into a water tank to separate the floating light impurities by density difference. Then spread the fruits on a drying bed with a thickness of no more than 5cm to avoid mold. Expose them to sunlight for 35 days. Turn the fruits once every hour for the first 7 days, turn them 4 times a day from 7 to 21 days, and stop turning them from 22 to 25 days. Then use a shelling machine to remove the peel, pulp and parchment layer, retaining the silver skin, to obtain Ethiopian sun-dried beans. S3. Roasting: Air-dry Ethiopian washed beans until the moisture content reaches 50%, then heat to 50℃ at a rate of 1℃ / min under conditions of 40℃ and a wind speed of 3m / s. Continue until the moisture content reaches 11%, then use a CCD color sorter to identify and remove moldy and insect-damaged beans until the color difference value ΔE < 2. Blend Ethiopian washed beans and Ethiopian sun-dried beans at a weight ratio of 2:5.5, then heat to 196℃ at a rate of 10℃ / min, hold for 9 minutes, and then heat to 210℃ at a rate of 4℃ / min to complete the roasting process. S4. Cooling: Air cooling is performed at a wind speed of 10 m / s to lower the bean temperature to below 35°C, resulting in coffee beans with a blended flavor.

[0040] Comparative Example 3 The difference from Example 1.1 is that in S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are roasted separately, specifically as follows: Ethiopian washed beans are air-dried until the moisture content reaches 50%. Then, at a temperature of 40°C and a wind speed of 3 m / s, the temperature is increased to 50°C at a rate of 1°C / min. This process continues until the moisture content reaches 11%. Moldy and insect-damaged beans are then identified and removed using a CCD color sorter until the color difference value ΔE < 2. The beans are then placed at 180°C and heated at a rate of 10°C / min until the moisture content decreases from 11% to 5%. Finally, the temperature is increased to 205°C and roasted for another 150 seconds to complete the roasting process. Ethiopian sun-dried beans were placed at 190°C and heated at a rate of 12°C / min until the moisture content dropped to 6%. The temperature was then increased to 210°C and roasted for another 180 seconds to complete the roasting process. Kenyan washed beans were centrifuged at 1200 rpm for 5 minutes, then dried at 60°C for 12 hours and at 35°C for 36 hours until the moisture content reached 12%. Moldy and insect-damaged beans were then identified and removed using a CCD color sorter until the color difference value ΔE < 2. The beans were then placed at 175°C and heated at a rate of 6°C / min until the moisture content decreased from 12% to 5%. The temperature was then increased to 195°C and roasted for another 90 seconds to complete the roasting process. The roasted Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans were blended in a weight ratio of 2:5.5:2.5.

[0041] Performance testing A sensory group of 100 volunteers was recruited, and members were required to drink at least one cup of coffee per week. The coffee beans with mixed flavors obtained in the examples and comparative examples were ground into powder, then brewed with water at 93°C, left to stand for 5 minutes, and the coffee grounds on the surface of the coffee liquid were gently pushed away and removed with a cupping spoon. Then the members began to taste the coffee and perceive the different flavors and tastes. The sensory evaluation was modified from the SCAA standard, as detailed in Table 1. The members' evaluation records are detailed in Table 2.

[0042] Table 1 Sensory Evaluation Criteria Table 2 Evaluation Record Sheet Data Analysis: As shown in Table 2, the coffee beans with blended flavor obtained in this application performed well in acidity, bitterness, and mouthfeel scores. In particular, more than half of the experimental groups of beans scored 3 points in the overall flavor score, proving that the preparation process of this application can stimulate the flavor substances inside the coffee beans, allowing the coffee beans to fully release their unique aroma and flavor, thereby producing coffee beans with blended flavor to meet consumers' demand for diverse flavors. The unique flavor formed by the coffee beans during the roasting process avoids the loss of flavor substances, further improving the taste and quality of the coffee beans. It can be seen that this application can improve the purity and quality of coffee beans by sorting and removing impurities and optimizing color sorting of Ethiopian and Kenyan green beans. By blending and roasting Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans obtained by different processing methods in a specific weight ratio, coffee beans with blended flavor can be prepared to meet consumers' demand for diverse flavors. Furthermore, roasting with a specific heating rate and temperature, and air cooling at a specific wind speed, helps to form a unique flavor and improve the taste and quality of the coffee beans.

[0043] In Comparative Examples 1-2, this application removed Ethiopian washed beans and Kenyan washed beans from the blending system, respectively. The results showed that the overall flavor score dropped to 1 point. It can be seen that Ethiopian washed beans have fresh floral and citrus notes, and therefore have very bright acidity, which can provide fresh citrus acidity and floral base. Ethiopian sun-dried beans have ripe berry aromas and fermented wine aromas. Due to the sun-drying process, they also have high sweetness, which increases the berry fermentation feeling and sweetness layer. Kenyan washed beans have blackcurrant flavor and unique phosphoric acidity. The beans are fuller and more uniform, bringing bright blackcurrant acidity and brown sugar finish. The three can form a complex and balanced flavor structure when blended in a certain weight ratio.

[0044] In Comparative Example 3, this application roasted Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans separately. The results showed that the overall flavor score dropped to 1 point. It can be seen that by mixing the three beans in a specific weight ratio and roasting them at a specific heating rate and temperature, this application can enable the coffee beans to form a unique blended flavor. Compared with the existing technology of roasting and controlling parameters separately, this not only saves process steps and costs, but also helps the coffee beans to form a unique flavor and improves the taste and quality of the coffee beans.

[0045] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A process for preparing coffee beans with a blended flavor, characterized in that, Includes the following steps: S1. Screening: Ethiopian and Kenyan green beans are sorted and impurities are removed, followed by color sorting optimization; S2. Pre-treatment: to obtain Ethiopian washed beans, Ethiopian sun-dried beans and Kenyan washed beans; S3. Roasting: Dehydrate Ethiopian washed beans and Kenyan washed beans separately, then mix them with Ethiopian sun-dried beans at a weight ratio of (2-3):(4-5.5):(2.5-3). Then, heat the mixture to 180-196℃ at a heating rate of 8-10℃ / min, hold it at that temperature for 7-9 minutes, and then heat it to 204-210℃ at a heating rate of 4-5℃ / min to finish roasting. S4. Cooling: Air cooling is performed at a wind speed of 8-10 m / s to lower the bean temperature to below 35°C, resulting in coffee beans with a blended flavor.

2. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, In step S3, the dehydration of Ethiopian washed beans specifically includes the following steps: Air dry until the moisture content reaches 45-50%, then heat to 50℃ at a rate of 0.8-1℃ / min under conditions of 35-40℃ and 3-4m / s wind speed until the moisture content reaches 10-11%, and optimize color sorting until the color difference value △E < 2.

3. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, In step S3, the dehydration of Kenyan washed beans specifically includes the following steps: Centrifuge at 1100-1200 rpm for 5-6 min, then dry at 55-60℃ for 12 h, and then dry at 35-40℃ for 36 h until the moisture content reaches 11-12%. Optimize color sorting until the color difference value ΔE < 2.

4. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, In step S3, Ethiopian washed beans and Kenyan washed beans are dehydrated separately and then blended with Ethiopian sun-dried beans in a weight ratio of 2.5:4.7:2.

8.

5. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, In step S3, Ethiopian washed beans, Ethiopian sun-dried beans, and Kenyan washed beans are mixed together, heated to 188°C at a heating rate of 9°C / min, held at that temperature for 3 minutes, and then heated to 207-208°C at a heating rate of 4.5°C / min to end the roasting process.

6. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, In step S1, color sorting optimization is performed until the color difference value △E < 3.

7. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, In step S2, Ethiopian raw beans are soaked, peeled and degummed, fermented and degummed, washed, and floated to obtain washed Ethiopian beans.

8. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, In step S2, Ethiopian raw beans are exposed to sunlight for 35-42 days, then the skin and gum are removed, and the beans are dehulled to obtain Ethiopian sun-dried beans.

9. The preparation process of coffee beans with a blended flavor according to claim 1, characterized in that, Kenyan green beans are soaked, peeled and degummed, fermented and degummed, double-washed, and floated to obtain washed Kenyan beans.

10. A coffee bean with a blended flavor obtained by the preparation process of the coffee bean with a blended flavor according to any one of claims 1-9.

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