Method for producing coffee extract

Abstract

Provided is a method for producing a coffee extract in which the aroma unique to coffee is enhanced and off-flavors are suppressed.　The present invention mixes: a coffee extract obtained by recovery until the extraction percentage is 1.0-20.0% (inclusive); and a coffee extract obtained due to an extract being subjected to a gas separation treatment according to a non-heating method, the extract being furthermore extracted after a first extraction step until the extraction percentage increases by 1.0-15.0% (inclusive).

Description

[Technical Field]

[0001] The present invention relates to a method for producing a coffee extract. Specifically, the present invention relates to a method for producing a coffee extract in which the aroma characteristic of coffee is enhanced and unpleasant flavors are suppressed. [Background technology]

[0002] When coffee beans are roasted, the flavor and aroma components contained in the green coffee beans undergo chemical changes, resulting in the unique taste and aroma of coffee. However, with the commonly known drip extraction method, it is known that the main components extracted change from the early to late stages of the coffee extraction process. For example, the desirable aroma components unique to coffee are mainly extracted in the early stages of extraction, while the components that contribute to unpleasant flavors are mainly extracted from the middle to late stages of extraction.

[0003] Various extraction methods for obtaining a good coffee extract have been investigated. For example, Japanese Patent Application Laid-Open No. 2018-068122 (Patent Document 1), Japanese Patent Application Laid-Open No. 2018-068247 (Patent Document 2), and Japanese Patent Application Laid-Open No. 2018-113986 (Patent Document 3) describe methods for producing a coffee extract using multi-stage extraction. However, even methods for extracting a coffee extract using multi-stage extraction still have the problem of extracting impurities. Furthermore, a method using activated carbon is known for removing impurities (Patent Document 4), but this method has the problem of simultaneously removing desirable aroma components along with the impurities. Under these circumstances, a method for providing a coffee extract that enhances the distinctive coffee aroma and suppresses impurities has been desired. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-068122 [Patent Document 2] Japanese Patent Application Publication No. 2018-068247 [Patent Document 3] Japanese Patent Application Publication No. 2018-113986 [Patent Document 4] Japanese Patent Application Laid-Open No. 2017-006015 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

[0005] An object of the present invention is to produce a coffee extract in which the aroma specific to coffee is enhanced and unpleasant flavors are suppressed. [Means for solving the problem]

[0006] While the aroma components specific to coffee are extracted in the early stages of the extraction process, using only low-extraction-rate coffee extract results in a very small amount of coffee extract obtained from a given amount of roasted and ground coffee beans, which creates a cost problem. On the other hand, if the extraction rate is increased to increase the amount of coffee extract obtained from a given amount of roasted and ground coffee beans, many of the impurity components extracted in the middle to late stages of the extraction process are also extracted.

[0007] As a result of extensive research, the inventors have found that a coffee extract that maintains the excellent aroma and flavor characteristic of coffee can be obtained by packing roasted and ground coffee beans into a column, supplying water to the column filled with the roasted and ground coffee beans, and extracting until the extraction rate reaches 1.0% to 20.0%. Furthermore, in the second extraction step, extraction is continued until the extraction rate increases by 1.0% to 15.0% after the first extraction step, and the off-flavor components in the resulting extract are removed by gas separation using a non-heating method, thereby reducing the off-flavor in the extract. They have also found that mixing the coffee extract obtained in the first extraction step with the coffee extract gas-separated after the second extraction step can produce a coffee extract with an enhanced coffee aroma and reduced off-flavor, thereby completing the present invention.

[0008] That is, the present invention relates to, but is not limited to, the following: (1) a) A first extraction step in which water is supplied to a column packed with roasted and ground coffee beans and a coffee extract is recovered until an extraction rate of 1.0% or more and 20.0% or less is reached, wherein the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans and is calculated by the following formula: (amount of coffee extract recovered in the first extraction step (kg) × Brix (%) of coffee extract recovered in the first extraction step) / (weight (kg) of roasted and ground coffee beans in the column), b) a second extraction step of recovering the coffee extract after the first extraction step until the extraction rate is further increased by 1.0% to 15.0%, wherein the extraction rate is calculated by the following formula: (amount of coffee extract recovered in the second extraction step (kg) × Brix (%) of coffee extract recovered in the second extraction step) / (weight (kg) of roasted and ground coffee beans in the column), c) a step of separating gas contained in the coffee extract obtained in the second extraction step without heating; and d) mixing the coffee extract obtained in the first extraction step with the coffee extract from which the gas has been separated; Including, A method for producing coffee extract. (2) The method according to (1), wherein the non-thermal gas separation in step c) is carried out by membrane treatment. (3) A manufacturing method according to (1) or (2), in which the amount of roasted and ground coffee beans packed per 1 L of column volume is 0.01 kg or more and 0.50 kg or less. (4) The method according to any one of (1) to (3), wherein the temperature of the water supplied to the column in the first extraction step is 40°C or higher and 120°C or lower. (5) The method according to any one of (1) to (4), wherein the temperature of the water supplied to the column in the second extraction step is 40°C or higher and 120°C or lower. (6) A method for enhancing the coffee aroma and suppressing unpleasant flavors in a coffee extract, comprising: a) a first extraction step in which water is supplied to a column packed with roasted and ground coffee beans and a coffee extract is recovered until an extraction rate of 1.0% or more and 20.0% or less is reached, wherein the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans and is calculated using the following formula: (amount of coffee extract recovered in the first extraction step (kg) × Brix (%) of coffee extract recovered in the first extraction step) / (weight (kg) of roasted and ground coffee beans in the column), b) a second extraction step of recovering the coffee extract after the first extraction step until the extraction rate is further increased by 1.0% to 15.0%, wherein the extraction rate is calculated by the following formula: (amount of coffee extract recovered in the second extraction step (kg) × Brix (%) of coffee extract recovered in the second extraction step) / (weight (kg) of roasted and ground coffee beans in the column), c) a step of separating gas contained in the coffee extract obtained in the second extraction step without heating; and d) mixing the coffee extract obtained in the first extraction step with the coffee extract from which the gas has been separated; Including, The method. [Effects of the Invention]

[0009] According to the present invention, it is possible to produce a coffee extract in which the aroma specific to coffee is enhanced and unpleasant flavors are suppressed. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 shows the results of a sensory evaluation test of coffee extracts with and without gas separation. DETAILED DESCRIPTION OF THE INVENTION

[0011] 1. Coffee extract production method In one aspect, the present invention provides a method for producing a coffee extract, comprising: a) a first extraction step of supplying water to a column packed with roasted and ground coffee beans and recovering a coffee extract until the extraction rate reaches 1.0% or more and 20.0% or less; b) a second extraction step of recovering the coffee extract after the first extraction step until the extraction rate increases by a further 1.0% or more and 15.0% or less; c) a step of separating gas contained in the coffee extract obtained in the second extraction step using a non-heating method; and d) a step of mixing the coffee extract obtained in the first extraction step with the coffee extract from which the gas has been separated. Here, the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans. The extraction rate in the first extraction step is calculated by (volume (kg) of coffee extract recovered in the first extraction step × Brix (%) of coffee extract recovered in the first extraction step) / (weight (kg) of roasted and ground coffee beans in the column). The extraction rate in the second extraction step is calculated by (volume (kg) of coffee extract recovered in the second extraction step × Brix (%) of coffee extract recovered in the second extraction step) / (weight (kg) of roasted and ground coffee beans in the column). This method makes it possible to produce a coffee extract that has an enhanced coffee aroma and reduced unpleasant flavors. In this specification, the term "coffee aroma" refers to the sweet aroma of freshly ground coffee. The term "unpleasant flavors" refers to unpleasant flavors such as burnt or medicinal odors.

[0012] 1-1. Roasted and ground coffee beans As used herein, "roasted and ground coffee beans" refers to beans obtained by grinding coffee beans that have been subjected to a process of heating and roasting green coffee beans, i.e., a "roasting process." In the present invention, the origin and variety of coffee beans used for the roasted and ground coffee beans are not particularly limited. For example, coffee bean origins include Brazil, Colombia, Tanzania, Mocha, Kilimanjaro, Mandheling, Blue Mountain, etc., and coffee bean varieties include Arabica, Robusta, Liberica, etc. Coffee beans from a single origin or variety may be used, or beans from different origins or varieties may be used in combination. The variety of coffee beans used in the method for producing a coffee extract of the present invention is not particularly limited, but it is preferable to use Arabica or Robusta beans.

[0013] In the present invention, the roasting method and conditions for obtaining roasted coffee beans from green coffee beans are not particularly limited. For example, methods such as direct flame, hot air, semi-hot air, charcoal fire, far-infrared, microwave, and superheated steam can be used, and equipment such as horizontal (horizontal) drum, vertical (vertical) drum, vertical rotating bowl, fluidized bed, and pressurized can be used, as long as the coffee beans are roasted to a degree of roasting appropriate for the desired purpose (light, cinnamon, medium, high, city, full city, French, or Italian) depending on the type of coffee beans.

[0014] In the roasted and ground coffee beans used in the present invention, the roasting temperature for obtaining roasted coffee beans is not particularly limited, but the roasting temperature is preferably 100°C or higher, 110°C or higher, 120°C or higher, 130°C or higher, 140°C or higher, 150°C or higher, or 160°C or higher, and more preferably 170°C or higher. Furthermore, the roasting temperature is preferably 300°C or lower, 290°C or lower, 280°C or lower, 270°C or lower, 260°C or lower, 250°C or lower, 240°C or lower, or 230°C or lower, and more preferably 220°C or lower. Typically, the roasting temperature range for obtaining roasted coffee beans for use in the present invention is preferably 100°C to 300°C, 110°C to 280°C, 120°C to 270°C, 130°C to 260°C, 140°C to 250°C, 150°C to 240°C, or 160°C to 230°C, and more preferably 170°C to 220°C. The roasting time for obtaining roasted coffee beans is not particularly limited, but is preferably 4 minutes or more, 5 minutes or more, 6 minutes or more, or 7 minutes or more, and more preferably 8 minutes or more. The roasting time is preferably 30 minutes or less, 25 minutes or less, 22 minutes or less, 20 minutes or less, 17 minutes or less, or 15 minutes or less, and more preferably 13 minutes or less. Typically, the roasting time range for obtaining roasted coffee beans is preferably 4 to 30 minutes, 5 to 25 minutes, 6 to 20 minutes, or 7 to 15 minutes, and more preferably 8 to 13 minutes. Furthermore, the roasting level of the roasted coffee beans is not particularly limited, but the roasting level, as measured by a colorimeter, is preferably 10 or more, 12 or more, 13 or more, or 14 or more, and more preferably 15 or more. Furthermore, the roasting level is preferably 30 or less, 28 or less, 27 or less, or 26 or less, and more preferably 25 or less. Typically, the roasting level of the roasted coffee beans, as measured by a colorimeter, is preferably 10 to 30, 12 to 28, 13 to 27, or 14 to 26, and more preferably 15 to 25. The roasting level is measured by placing the ground beans in a cell, thoroughly tapping, and then measuring with a spectrophotometer. As the spectrophotometer, SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd. or the like can be used.

[0015] Furthermore, the grinding method for obtaining the roasted and ground coffee beans of the present invention is not particularly limited, and general methods such as dry grinding and wet grinding can be used.

[0016] 1-2.Coffee extract As used herein, the term "coffee extract" refers to a liquid extracted from coffee beans. Examples of coffee extracts include extracts obtained by extracting roasted coffee beans with a solvent such as water, diluted or concentrated versions of such extracts, and slurries containing coffee beans or ground coffee beans. Furthermore, a coffee beverage can be obtained by appropriately diluting the "coffee extract" and optionally mixing it with other ingredients.

[0017] 1-3.First extraction process The method for producing a coffee extract of the present invention includes a first extraction step in which water is supplied to a column packed with roasted and ground coffee beans and the coffee extract is recovered until the extraction rate reaches 1.0% or more and 20.0% or less, and a second extraction step in which the coffee extract is recovered after the first extraction step until the extraction rate increases further by 1.0% or more and 15.0% or less.

[0018] Because the pleasant aroma components unique to coffee are obtained in the early stages of the extraction process, in order to obtain a coffee extract containing a large amount of the aroma components unique to coffee, it is preferable to recover an extract with a low extraction rate. Therefore, the method for producing a coffee extract of the present invention includes, as the first extraction step, a step of supplying water to a column packed with roasted and ground coffee beans and recovering the coffee extract until the extraction rate reaches 1.0% or more and 20.0% or less.

[0019] The temperature of the water supplied in the first extraction step is preferably 40°C or higher, 45°C or higher, 50°C or higher, 55°C or higher, 60°C or higher, or 65°C or higher, and more preferably 70°C or higher. The temperature of the water supplied in the first extraction step is preferably 120°C or lower, 116°C or lower, 112°C or lower, 108°C or lower, 106°C, or 104°C or lower, and more preferably 100°C or lower. Typically, the temperature of the water supplied in the extraction step is preferably in the range of 40°C to 120°C, 45°C to 116°C, 50°C to 112°C, 55°C to 108°C, 60°C to 106°C, or 65°C to 104°C, and more preferably 70°C to 100°C.

[0020] The extraction rate in the first extraction step is preferably 3.0% or more, 5.0% or more, 7.0% or more, 7.5% or more, 8.0% or more, 8.5% or more, 9.0% or more, or 9.5% or more, and more preferably 10.0% or more. The extraction rate in the first extraction step is preferably 18.5% or less, 18.0% or less, 17.5% or less, 17.0% or less, 16.5% or less, 16.0% or less, or 15.5% or less, and more preferably 15.0% or less. Typically, the range of extraction rate in the first extraction step is preferably 1.0% to 20.0%, 3.0% to 20.0%, 5.0% to 20.0%, 7.0% to 20.0%, 7.5% to 18.0%, 8.0% to 17.0%, 8.5% to 16.5%, 9.0% to 16.0%, or 9.5% to 15.5%, and more preferably 10.0% to 15.0%.

[0021] Here, the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans, and the extraction rate in the first extraction step is calculated by (amount (kg) of coffee extract recovered in the first extraction step × Brix (%) of coffee extract recovered in the first extraction step) / (weight (kg) of roasted and ground coffee beans in the column).

[0022] The amount of roasted and ground coffee beans packed into the extraction column is not particularly limited, but is preferably 0.01 kg or more, 0.05 kg or more, 0.06 kg or more, 0.07 kg or more, or 0.08 kg or more per liter of column volume, and more preferably 0.09 kg or more. Also, the amount of roasted and ground coffee beans packed into the extraction column is preferably 0.50 kg or less, 0.40 kg or less, or 0.30 kg or less per liter of column volume, and more preferably 0.20 kg or less. Typically, the weight range of roasted and ground coffee beans to be packed into the extraction column is 0.01 kg to 0.50 kg per liter of column volume (0.01 kg / L to 0.50 kg / L), preferably 0.05 kg / L to 0.50 kg / L, 0.065 kg / L to 0.40 kg / L, or 0.08 kg / L to 0.30 kg / L, and more preferably 0.09 kg / L to 0.20 kg / L.

[0023] The amount of coffee extract collected from the extraction column is not particularly limited as long as it is extracted to achieve the desired extraction rate, but the amount of coffee extract collected from the extraction column is preferably 0.1 kg or more, 0.3 kg or more, 0.5 kg or more, or 0.6 kg or more per 1 kg of raw material, and more preferably 0.75 kg or more per 1 kg of raw material. The amount of coffee extract collected from the extraction column is preferably 15 kg or less, 12 kg or less, 10 kg or less, 8 kg or less, or 6 kg or less per 1 kg of raw material, and more preferably 5 kg or less per 1 kg of raw material. Typically, the amount of coffee extract collected from the extraction column is preferably 0.1 kg to 15 kg, 0.3 kg to 12 kg, 0.5 kg to 10 kg, or 0.6 kg to 6 kg per 1 kg of raw material, and more preferably 0.75 kg to 5 kg per 1 kg of raw material.

[0024] In the first extraction step of the method for producing a coffee extract of the present invention, the rate at which water (kg) is supplied per 1 kg of roasted and ground coffee beans is not particularly limited, but it is preferable to supply water at a flow rate of 1 kg / h or more, 2 kg / h or more, 3 kg / h or more, 4 kg / h or more, or 5 kg / h or more per 1 kg of roasted and ground coffee beans, and it is preferable to supply water at a flow rate of 80 kg / h or less, 70 kg / h or less, 60 kg / h or less, 50 kg / h or less, or 40 kg / h or less. Typically, in the first extraction step of the method for producing a coffee extract of the present invention, the rate at which water is supplied per 1 kg of roasted and ground coffee beans is preferably 1 kg / h to 80 kg / h, 2 kg / h to 70 kg / h, 3 kg / h to 60 kg / h, 4 kg / h to 50 kg / h, or 5 kg / h to 40 kg / h. In this specification, for example, supplying water at a flow rate of 1 kg / h per 1 kg of roasted and ground coffee beans means supplying 5 kg of water per hour to the column when 5 kg of roasted and ground coffee beans are used.

[0025] The coffee solids concentration of the coffee extract obtained in the first extraction step of the coffee extract production method of the present invention is not particularly limited, but is preferably 0.5% or more, 0.75% or more, 1.0% or more, 1.25% or more, 1.5% or more, 1.75% or more, or 2.0% or more in Brix value, and is preferably 20% or less, 17.5% or less, 15% or less, 12.5% ​​or less, 10% or less, or 7.5% or less. Typically, the coffee solids concentration of the coffee extract obtained in the first extraction step of the coffee extract production method of the present invention is preferably in the range of 0.5% to 20%, 1.0% to 17.5%, 1.25% to 15%, 1.5% to 12.5%, 1.75% to 10%, or 2.0% to 7.5% in Brix value.

[0026] The Brix value is the refractive index measured at 20°C using a saccharometer or refractometer, converted to a mass / mass percentage of the sucrose solution based on the conversion table of the International Commission on Uniform Methods of Sugar Analysis (ICUMSA), and represents the soluble solids content of a beverage. The unit may also be expressed as "Bx," "%," or "degrees." The lower the Brix value of a beverage, the lower the content of soluble solids, including sugars.

[0027] 1-4.Second extraction process The second extraction step of the coffee extract manufacturing method of the present invention includes a step of recovering the coffee extract after the first extraction step until the extraction rate increases by a further 1.0% to 15.0%.

[0028] The temperature of the water supplied in the second extraction step is preferably 40°C or higher, 45°C or higher, 50°C or higher, 55°C or higher, 60°C or higher, or 65°C or higher, and more preferably 70°C or higher. Furthermore, the temperature of the water supplied in the second extraction step is preferably 120°C or lower, 116°C or lower, 112°C or lower, 108°C or lower, 106°C, or 104°C or lower, and more preferably 100°C or lower. Typically, the temperature of the water supplied in the second extraction step is preferably within the range of 40°C to 120°C, 45°C to 116°C, 50°C to 112°C, 55°C to 108°C, 60°C to 106°C, or 65°C to 104°C, and more preferably 70°C to 100°C.

[0029] In the second extraction step, it is preferable to recover the coffee extract until the extraction rate of the coffee extract increases by 3.0% or more, 5.0% or more, 5.5% or more, 6.0% or more, 6.5% or more, 7.0% or more, or 7.5% or more. In the second extraction step, it is preferable to recover the coffee extract until the extraction rate of the coffee extract increases by 14.5% or less, 14.0% or less, 13.5% or less, 13.0% or less, or 12.5% ​​or less. Typically, in the second extraction step, it is preferable to recover the coffee extract until the extraction rate of the coffee extract increases by 1.0% to 15.0%, 3.0% to 15.0%, 5.0% to 15.0%, 5.5% to 14.5%, 6.0% to 14.0%, 6.5% to 13.5%, 7.0% to 13.0%, or 7.5% to 12.5%.

[0030] Here, the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans, and the extraction rate in the second extraction step is calculated by (amount (kg) of coffee extract recovered in the second extraction step × Brix (%) of coffee extract recovered in the second extraction step) / (weight (kg) of roasted and ground coffee beans in the column).

[0031] The amount of coffee extract collected from the extraction column is not particularly limited as long as it is extracted to achieve the desired extraction rate, but the amount of coffee extract collected from the extraction column is preferably 0.5 kg or more, 1.0 kg or more, 1.5 kg or more, 2.0 kg or more, or 2.5 kg or more per 1 kg of raw material, and more preferably 3.0 kg or more per 1 kg of raw material. The amount of coffee extract collected from the extraction column is preferably 15 kg or less, 13.5 kg or less, 12 kg or less, 11 kg or less, or 10 kg or less per 1 kg of raw material, and more preferably 9.0 kg or less per 1 kg of raw material. Typically, the amount of coffee extract collected from the extraction column is preferably 0.5 kg to 15 kg, 1.0 kg to 13.5 kg, 1.5 kg to 12 kg, 2.0 kg to 11 kg, or 2.5 kg to 10 kg per 1 kg of raw material, and more preferably 3.0 kg to 9.0 kg per 1 kg of raw material.

[0032] In the second extraction step of the coffee extract production method of the present invention, the rate at which water is supplied per 1 kg of roasted and ground coffee beans is not particularly limited, but it is preferable to supply water at a flow rate of 1 kg / h or more, 2 kg / h or more, 3 kg / h or more, 4 kg / h or more, or 5 kg / h or more per 1 kg of roasted and ground coffee beans, and it is preferable to supply water at a flow rate of 80 kg / h or less, 70 kg / h or less, 60 kg / h or less, 50 kg / h or less, or 40 kg / h or less. Typically, in the second extraction step of the coffee extract production method of the present invention, the rate at which water is supplied per 1 kg of roasted and ground coffee beans is preferably 1 kg / h to 80 kg / h, 2 kg / h to 70 kg / h, 3 kg / h to 60 kg / h, 4 kg / h to 50 kg / h, or 5 kg / h to 40 kg / h.

[0033] Furthermore, the coffee solids concentration of the coffee extract obtained in the second extraction step of the coffee extract manufacturing method of the present invention is not particularly limited, but is preferably 0.05% or more, 0.10% or more, 0.15% or more, 0.20% or more, 0.25% or more, 0.30% or more, 0.35% or more, 0.40% or more, 0.45% or more, or 0.50% or more in Brix value, and is preferably 9.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, or 3.0% or less. Typically, the coffee solids concentration of the coffee extract obtained in the first extraction step of the coffee extract manufacturing method of the present invention preferably ranges in Brix value from 0.05% to 9.0%, 0.10% to 7.0%, 0.20% to 6.0%, 0.30% to 5.0%, 0.40% to 4.0%, or 0.50% to 3.0%.

[0034] 1-5. Gas separation process The method for producing a coffee extract of the present invention includes, after the second extraction step, a step of separating gas contained in the coffee extract obtained in the second extraction step using a non-heating method.

[0035] As mentioned above, while the pleasant aroma components unique to coffee are extracted in the early stages of the extraction process, using only a low-extraction-rate coffee extract results in a very small amount of coffee extract obtained from a given amount of roasted and ground coffee beans, which creates cost problems. On the other hand, increasing the extraction rate to increase the amount of coffee extract obtained from a given amount of roasted and ground coffee beans also results in a large amount of impurity components extracted in the middle to later stages of the extraction process. That is, a first extraction step in which a coffee extract with an extraction rate of 1.0% to 20.0% is recovered produces a coffee extract containing many of the aroma components unique to coffee, while a second extraction step in which coffee is further recovered after the first extraction step until the extraction rate increases by 1.0% to 15.0% produces a coffee extract containing a certain amount of impurity components. Therefore, the coffee extract production method of the present invention includes a step of separating gases contained in the coffee extract after the second extraction step using a non-heating method, thereby removing the impurity components from the coffee extract after the second extraction step.

[0036] The method of gas separation using a non-heating method is not particularly limited as long as it can remove easily volatilized components from the coffee extract. For example, pervaporation and membrane separation can be used. Pervaporation is also known as pervaporation or permeation evaporation, and specifically involves placing the liquid to be separated on one side of a membrane and applying a vacuum to the other side to selectively remove the vaporized components that have permeated the membrane. Membrane separation is a method of selectively separating gases using a membrane that allows only vaporized components to permeate. Examples of membranes used for gas separation include hollow fiber membranes.

[0037] In one embodiment, the gas separation after the second extraction step can be performed using a Liqui-Cel. Liqui-Cel is a separation membrane module that uses porous hollow fiber membranes and is capable of removing gas from a liquid. The gas separation conditions using Liqui-Cel are not particularly limited as long as they can remove the unpleasant flavor components from the coffee extract. For example, gas separation can be performed under the following conditions: <Liqui-Cel processing conditions> Equipment: 3M TM Liqui-Cel TM MM-1.7×8.75 (manufactured by 3M) Number of pieces used: 1 Amount of processed extract: 1.5 kg Processing time: 30 min Pump: 250ml / min Temperature: Room temperature (about 20℃) Nitrogen flow rate: 3L / min Vacuum level: -0.091MPa

[0038] In the method for producing a coffee extract of the present invention, the solids concentration in the coffee extract does not change before and after gas separation, but the solids concentration of the coffee extract after gas separation from the second extraction step is not particularly limited, but is preferably 0.05% or more, 0.10% or more, 0.15% or more, 0.20% or more, 0.25% or more, 0.30% or more, 0.35% or more, 0.40% or more, 0.45% or more, or 0.50% or more in Brix value, and is preferably 9.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, 4.5% or less, 4.0% or less, 3.5% or less, or 3.0% or less. Typically, the range of solids concentration after gas separation of the coffee extract following the second extraction step is preferably 0.05% to 9.0%, 0.10% to 7.0%, 0.20% to 6.0%, 0.30% to 5.0%, 0.40% to 4.0%, or 0.50% to 3.0% in Brix value.

[0039] 1-6.Mixing process The method for producing a coffee extract of the present invention includes a step of mixing the coffee extract obtained in the first extraction step with the coffee extract separated by gas after the second extraction step. As described above, the first extraction step, in which the coffee extract is collected until the extraction rate reaches 1.0% to 20.0%, produces a coffee extract containing a large amount of aroma components specific to coffee. Furthermore, the second extraction step, in which the coffee extract is collected after the first extraction step until the extraction rate further increases by 1.0% to 15.0%, produces a coffee extract containing a certain amount of impurity components. However, by separating the impurity components from the coffee extract, a coffee extract from which the impurity components have been removed can be produced. Therefore, by mixing the coffee extract obtained in the first extraction step with the coffee extract separated by gas after the second extraction step, a coffee extract with an enhanced coffee aroma and reduced impurity can be produced.

[0040] In the method for producing a coffee extract of the present invention, the mixing ratio of the coffee extract obtained in the first extraction step and the coffee extract from which gas has been separated after the second extraction step is not particularly limited, and the coffee extract obtained in the first extraction step and the coffee extract from which gas has been separated after the second extraction step can be mixed as appropriate so that the coffee extract after mixing has a desired Brix value. In the method for producing a coffee extract of the present invention, the concentration of the coffee extract obtained by mixing the coffee extract obtained in the first extraction step and the coffee extract from which gas has been separated after the second extraction step is preferably 0.5% or more, 0.75% or more, 1.0% or more, 1.25% or more, 1.5% or more, 1.75% or more, or 2.0% or more in terms of Brix value, and is preferably 10% or less, 9.0% or less, 8.0% or less, 7.0% or less, 6.0% or less, 5.0% or less, or 4.0% or less. Typically, in the method for producing a coffee extract of the present invention, the concentration of the coffee extract obtained by mixing the coffee extract obtained in the first extraction step with the coffee extract from which gas has been separated after the second extraction step is preferably in the range of 0.5% to 10%, 1.0% to 9.0%, 1.25% to 8.0%, 1.50% to 7.0%, 1.75% to 6.0%, or 2.0% to 4.0% in Brix value.

[0041] 1-7.Other The method for producing a coffee extract of the present invention can also include a heat sterilization step. When the method for producing a coffee extract of the present invention includes a heat sterilization step, the heat sterilization method is not particularly limited, and known methods such as FP sterilization and UHT sterilization can be used. For example, a heat-sterilized coffee extract or a diluted solution thereof can be produced by a method in which the coffee extract itself or a diluted solution thereof is heat sterilized and then packaged in a container, or a method in which the coffee extract or a diluted solution thereof is packaged in a container and then heat sterilized.

[0042] Furthermore, the method for producing a coffee extract of the present invention can also include a freezing step, if necessary.

[0043] 1-8. Coffee drinks, etc. In one aspect, the present invention provides a coffee extract produced by the aforementioned method for producing a coffee extract, which can enhance the coffee aroma and suppress unpleasant flavors.

[0044] In one aspect, the present invention provides a coffee beverage using the coffee extract produced by the aforementioned method for producing a coffee extract. The coffee beverage may contain milk, sugars, sweeteners, or other commonly used additives as appropriate.

[0045] In one embodiment, the coffee beverage can be packed in any container to produce a bottled coffee beverage. In the present invention, the container into which the coffee beverage is packed can be appropriately selected depending on the sterilization method and storage method, and any commonly used container can be used, such as an aluminum can, a steel can, a PET bottle, a glass bottle, or a paper container. When packing the coffee beverage of the invention according to this embodiment into a container, either a hot pack filling method or an aseptic filling method can be used, but the hot pack filling method is preferred.

[0046] 2. Method for enhancing the coffee aroma and suppressing unpleasant flavors in coffee extract In one aspect, the present invention provides a first extraction step of supplying water to a column packed with roasted and ground coffee beans and recovering a coffee extract until an extraction rate of 1.0% or more and 20.0% or less is reached, wherein the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans and is calculated by the following formula: (amount of coffee extract recovered in the first extraction step (kg) × Brix (%) of coffee extract recovered in the first extraction step) / (weight (kg) of roasted and ground coffee beans in the column), b) a second extraction step of recovering the coffee extract after the first extraction step until the extraction rate is further increased by 1.0% to 15.0%, wherein the extraction rate is calculated by the following formula: (amount of coffee extract recovered in the second extraction step (kg) × Brix (%) of coffee extract recovered in the second extraction step) / (weight (kg) of roasted and ground coffee beans in the column), c) a step of separating gas contained in the coffee extract obtained in the second extraction step without heating; and and d) a step of mixing the coffee extract obtained in the first extraction step with the coffee extract from which the gas has been separated. This method makes it possible to enhance the coffee aroma and suppress the unpleasant taste in the coffee extract. Furthermore, in the method for enhancing the coffee aroma and suppressing the unpleasant taste in the coffee extract, the roasted and ground coffee beans, the first extraction step, the second extraction step, the gas separation step, and the mixing step are as described in the section "1. Method for producing coffee extract." [Example]

[0047] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0048] Example 1: Preparation of coffee extract (1) Manufacturing of roasted and ground coffee beans Green coffee beans (produced in Brazil, No. 2 SS) were roasted in a coffee roaster so that the L value was 20. The roasted coffee beans were then ground in a grinder to obtain roasted and ground coffee beans.

[0049] (2) Coffee extract production (i) First Extraction Step and Second Extraction Step An extraction column (column volume: 10 L) was packed with the roasted and ground coffee beans produced in (1) above so that the bean weight was 1.0 kg per column, and then water at 94°C was supplied to the column until 9 kg of extract had been collected. After supplying water to the column, 1 kg of the resulting extract was collected, and the Brix value of each fraction was measured. The extraction rate was calculated using the following formula. (Amount of liquid collected (kg) x Brix (%) / (Weight of roasted coffee beans (kg))

[0050] Table 1 below shows the Brix value, extraction rate and cumulative extraction rate of each fraction. [Table 1]

[0051] Of the obtained fractions, the first 1 to 3 fractions were of good quality and had little impurity, so they were not subjected to Liqui-Cel removal of impurities, but the latter 4 to 9 fractions were subjected to Liqui-Cel treatment to verify whether impurities would be reduced. The Liqui-Cel treatment conditions were as follows:

[0052] <Liqui-Cel processing conditions> Equipment: 3M TM Liqui-Cel TM (Manufactured by 3M) Number of pieces used: 1 Extract processing volume: 1.5 kg Processing time: 30 min Extraction liquid pump: 250 ml / min Temperature: Room temperature (about 20℃) Nitrogen flow rate: 3L / min Vacuum level: -0.091MPa

[0053] Next, the first three fractions of coffee extract were mixed with the last six fractions of coffee extract that had been Liqui-Cel processed at a 1:2 ratio. Specifically, the ratio of the product of the Brix value of each extract and the blend volume was equal to the ratio of the extraction rates of each extract. That is, the cumulative extraction rate and Brix value of the first three fractions were 14.47% and 4.82%, respectively, while the cumulative extraction rate and Brix value of the last six fractions that had been Liqui-Cel processed were 10.33% and 1.72%, respectively. Therefore, the blend volume ratio of the first three fractions to the last six fractions that had been Liqui-Cel processed was 1:2. After mixing, the Brix value of the sample was adjusted to 1.3, sterilized at 115°C for 5 minutes, and then sensory evaluation was performed.

[0054] Example 2: Sensory evaluation of coffee extract Example 1 was a coffee extract prepared by mixing the first 1-3 fractions of the coffee extract produced in Example 1 with the second 4-9 fractions of the coffee extract that had been treated with Liqui-Cel. Comparative Example 1 was a coffee extract prepared by mixing the first 1-3 fractions of the coffee extract with the second 4-9 fractions of the coffee extract that had not been treated with Liqui-Cel. A sensory evaluation was conducted by expert panelists (five people) on Example 1 and Comparative Example 1. In the sensory evaluation, the expert panelists drank approximately 50 mL of each sample beverage and evaluated the sweet aroma (sweet aroma) specific to coffee and the absence of off-flavors (off-flavors) such as burnt or medicinal odors. Specifically, the stronger the sweet aroma was perceived, the higher the score, and the evaluation was performed on a scale of 0 to 100. The less off-flavors were perceived, the higher the score, and the higher the score, and the more off-flavors were perceived, the higher the score, and the evaluation was performed on a scale of 0 to 100. Furthermore, as a benchmark, a coffee extract (diluted to Brix 1.3%) was prepared by drip-extracting roasted and ground Brazilian No. 2 SS coffee beans in the usual way. The sweet aroma of this coffee extract was given a score of 0, and the absence of unpleasant flavors was given a score of 50.

[0055] The results are shown in Figure 1. As is clear from Figure 1, by producing a coffee extract using the Liqui-Cel treatment of the present invention, the unpleasant flavors in the coffee extract were reduced, and as a result, the sweet aroma unique to coffee became more pronounced. [Industrial Applicability]

[0056] INDUSTRIAL APPLICABILITY The present invention relates to a novel means for providing a coffee extract in which the characteristic coffee aroma is enhanced and impurities are suppressed, and therefore has high industrial applicability.

Claims

1. a) a first extraction step of supplying water to a column packed with roasted and ground coffee beans and recovering a coffee extract until an extraction rate of 1.0% to 20.0% is reached, where the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans and is calculated by the following formula: (amount of coffee extract recovered in the first extraction step (kg) × Brix (%) of coffee extract recovered in the first extraction step) / (weight (kg) of roasted and ground coffee beans in the column), b) a second extraction step of recovering the coffee extract after the first extraction step until the extraction rate is further increased by 1.0% to 15.0%, wherein the extraction rate is calculated according to the following formula: (amount of coffee extract recovered in the second extraction step (kg) × Brix (%) of coffee extract recovered in the second extraction step) / (weight (kg) of roasted and ground coffee beans in the column), c) a step of separating gas contained in the coffee extract obtained in the second extraction step by a non-heating method; and d) mixing the coffee extract obtained in the first extraction step with the coffee extract from which the gas has been separated; Including, A method for producing a coffee extract.

2. The method according to claim 1 , wherein the non-thermal gas separation in step c) is carried out by a membrane process.

3. The method according to claim 1 or 2, wherein the amount of roasted and ground coffee beans packed per 1 L of column volume is 0.01 kg or more and 0.50 kg or less.

4. The method according to any one of claims 1 to 3, wherein the temperature of the water supplied to the column in the first extraction step is 40°C or higher and 120°C or lower.

5. The method according to any one of claims 1 to 4, wherein the temperature of the water supplied to the column in the second extraction step is 40°C or higher and 120°C or lower.

6. A method for enhancing a coffee-specific aroma and suppressing unpleasant flavors in a coffee extract, comprising the steps of: a) a first extraction step of supplying water to a column packed with roasted and ground coffee beans and recovering a coffee extract until an extraction rate of 1.0% to 20.0% is reached, where the extraction rate is defined as the solids concentration (Brix) in the recovered coffee extract relative to the weight of the roasted and ground coffee beans and is calculated by the following formula: (amount of coffee extract recovered in the first extraction step (kg) × Brix (%) of coffee extract recovered in the first extraction step) / (weight (kg) of roasted and ground coffee beans in the column), b) a second extraction step of recovering the coffee extract after the first extraction step until the extraction rate is further increased by 1.0% to 15.0%, wherein the extraction rate is calculated according to the following formula: (amount of coffee extract recovered in the second extraction step (kg) × Brix (%) of coffee extract recovered in the second extraction step) / (weight (kg) of roasted and ground coffee beans in the column), c) a step of separating gas contained in the coffee extract obtained in the second extraction step by a non-heating method; and d) mixing the coffee extract obtained in the first extraction step with the coffee extract from which the gas has been separated; Including, The method.

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