coffee extract

Abstract

To provide a coffee extract with increased coffee-specific aroma and reduced off-flavors.SOLUTION: A coffee extract comprises 2,3-butanedione, guaiacol and 4-ethylguaiacol. In the coffee extract, the ratio of (a) the concentration (ppb) of 2,3-butanedione to (b) the total concentration (ppb) of guaiacol and 4-ethylguaiacol [(a) / (b)] is 3.1 or more, and the coffee solid content (Brix) is 20-40%.SELECTED DRAWING: None

Description

[Technical Field]

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

[0002] It is desirable to obtain a coffee extract from commonly used coffee ingredients that retains the distinctive coffee aroma and minimizes unpleasant flavors. The development of such a coffee extract would be a major commercial advantage in that it would enable the stable provision of high-quality coffee extracts at low cost.

[0003] Patent Document 1 describes a method for producing a concentrated coffee extract by passing a hot aqueous medium through a set of extraction towers (percolator towers) and combining an evaporation and concentration step with the extraction step. Patent Document 2 also describes a method for producing a concentrated coffee extract by passing hot water through a set of extraction columns. However, because typical coffee ingredients also contain many impurity components, there is a problem in that when coffee is extracted from such ingredients using a conventional extraction method, the impurity components are extracted along with the pleasant coffee aroma. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 47-20370 [Patent Document 2] Japanese Patent Application Publication No. 52-125670 DISCLOSURE OF THE INVENTION [Problem to be solved by the invention]

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

[0006] As a result of intensive research conducted by the present inventors to solve the above-mentioned problems, they have found that, in a coffee extract containing 2,3-butanedione, guaiacol, and 4-ethylguaiacol, a coffee solids concentration (Brix) of the coffee extract is adjusted to 1%, and the coffee extract is adjusted so that the ratio [(A) / (B)] of (A) the peak area ratio of 2,3-butanedione to (B) the sum of the peak area ratios of guaiacol and 4-ethylguaiacol is 7.0 or more. The present inventors have also discovered that a coffee extract containing 2,3-butanedione, guaiacol, and 4-ethylguaiacol can be provided with an enhanced coffee aroma and reduced unpleasant flavors by adjusting the ratio [(a) / (b)] of (a) the concentration (ppb) of 2,3-butanedione to (b) the total concentration (ppb) of guaiacol and 4-ethylguaiacol to be 3.1 or more, thereby completing the present invention.

[0007] That is, the present invention relates to, but is not limited to, the following: (1) A coffee extract containing 2,3-butanedione, guaiacol, and 4-ethylguaiacol, wherein the coffee extract has a coffee solids concentration (Brix) adjusted to 1% and the ratio of (A) the peak area ratio of 2,3-butanedione to (B) the sum of the peak area ratios of guaiacol and 4-ethylguaiacol [(A) / (B)] is 7.0 or more, wherein the peak area ratio is the ratio of the peak area of ​​each component to the peak area of ​​borneol when the peak areas are measured by gas chromatography-mass spectrometry using 10 ppb of borneol as an internal standard. (2) The coffee extract according to (1), wherein the ratio [(A) / (B)] is 8.0 to 30.0. (3) The coffee extract according to (1) or (2), having a coffee solids concentration (Brix) of 20 to 40%. (4) A beverage comprising the coffee extract according to any one of (1) to (3). (5) A coffee extract containing 2,3-butanedione, guaiacol, and 4-ethylguaiacol, The coffee extract, wherein the ratio [(a) / (b)] of (a) the concentration (ppb) of 2,3-butanedione to (b) the total concentration (ppb) of guaiacol and 4-ethylguaiacol in the coffee extract is 3.1 or more. (6) The coffee extract according to (5), wherein the ratio [(a) / (b)] is 3.4 to 30.0. (7) The coffee extract according to (5) or (6), having a coffee solids concentration (Brix) of 20 to 40%. (8) A beverage comprising the coffee extract according to any one of (5) to (7). [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a coffee extract in which the aroma specific to coffee is enhanced and unpleasant flavors are suppressed. DETAILED DESCRIPTION OF THE INVENTION

[0009] 1. Coffee extract In one aspect, the present invention provides a coffee extract containing 2,3-butanedione, guaiacol, and 4-ethylguaiacol, wherein the ratio [(A) / (B)] of the peak area ratio of (A) 2,3-butanedione to the sum of the peak area ratios of (B) guaiacol and 4-ethylguaiacol in a solution adjusted to a coffee solids concentration (Brix) of 1% is 7.0 or greater. In another aspect, the present invention provides a coffee extract containing 2,3-butanedione, guaiacol, and 4-ethylguaiacol, wherein the ratio [(a) / (b)] of the concentration (ppb) of (a) 2,3-butanedione to the sum of the concentration (ppb) of guaiacol and 4-ethylguaiacol in the coffee extract is 3.1 or greater. This configuration makes it possible to provide a concentrated coffee extract that enhances the distinctive coffee aroma and suppresses unpleasant flavors. In this specification, the terms "coffee aroma" and "top aroma" refer to the sweet aroma of freshly ground coffee. Also, in this specification, "highly clean" refers to the absence of any unpleasant flavors.

[0010] 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 extracts, and slurries containing coffee beans or ground coffee beans. Therefore, in one embodiment, the coffee extract of the present invention is a concentrated coffee extract. Note that, as used herein, the term "concentrated coffee extract" refers to an extract having a higher coffee solids concentration than a typical coffee extract.

[0011] As used herein, "coffee beans" refers to any of green coffee beans, roasted coffee beans, and roasted and ground coffee beans. Furthermore, as used herein, "green coffee beans" refers to coffee beans before they undergo a roasting process, which is a process in which coffee beans are heated and roasted, "roasted coffee beans" refers to coffee beans after they have undergone a roasting process, and "roasted and ground coffee beans" refers to beans obtained by grinding coffee beans that have undergone a roasting process.

[0012] In the present invention, the origin or variety of coffee beans is 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 production of the 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] The roasting temperature for obtaining the roasted and ground coffee beans used in the present invention is not particularly limited, but is preferably 100 to 300°C, more preferably 150 to 250°C, and particularly preferably 170 to 220°C. The roasting time for obtaining the roasted coffee beans is also not particularly limited, but is preferably 5 to 30 minutes, more preferably 10 to 25 minutes, and particularly preferably 15 to 20 minutes. The roasting level of the roasted coffee beans is also not particularly limited, but is preferably 10 to 30, more preferably 10 to 25, and particularly preferably 15 to 25, using the L value measured with a colorimeter as an index of roasting level. The roasting level is measured by placing the ground beans in a cell, thoroughly tapping, and then measuring with a spectrophotometer. The SE-2000 manufactured by Nippon Denshoku Industries Co., Ltd., or the like, can be used as the spectrophotometer.

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

[0016] 1-1,2,3-butanedione The coffee extract of the present invention contains 2,3-butanedione, a component that contributes to the unique coffee aroma. The peak area ratio of 2,3-butanedione in a solution of the coffee extract of the present invention, adjusted to a coffee solids concentration (Brix) of 1%, is not particularly limited as long as the ratio [(A) / (B)] of the peak area ratio of (A) 2,3-butanedione to the sum of the peak area ratios of (B) guaiacol and 4-ethylguaiacol falls within a specified range, but is preferably 0.3 to 3.0, more preferably 0.5 to 2.0, and even more preferably 0.8 to 1.2. If the peak area ratio of (A) 2,3-butanedione in the coffee extract of the present invention is too low, the unique coffee aroma will be insufficient. On the other hand, if the peak area ratio of (A) 2,3-butanedione is too high, the overall balance of the coffee aroma will be disrupted, resulting in an unusual sweetness that is different from coffee.

[0017] As used herein, "peak area ratio" refers to the ratio of the peak area of ​​a target component to the peak area of ​​borneol (10 ppb) when the peak area is measured by gas chromatography-mass spectrometry using 10 ppb of borneol as an internal standard. Quantitative analysis methods include the calibration curve method, which uses a standard substance for the target component, and the internal standard method, which uses an internal standard solution not present in the sample. However, since both methods are calculated based on the peak area values ​​obtained when gas chromatography-mass spectrometry is performed, the values ​​calculated by both methods are considered to be correlated. The gas chromatography-mass spectrometry conditions are as follows: GC main unit: Agilent Technologies 7890A ·MS Detector: Agilent Technologies 5975C inert XL MSD with Triple-Axis Detector Pretreatment device: MultiPurpose Sampler MPS for GC Sample injection conditions: DHS (dynamic headspace) method Sample temperature: 80℃ Pressure 160kPa Septum purge flow rate: 3 mL / min Splitless Mode Column: HP-INNOWAX (length: 60 m, diameter: 0.250 mm, thickness: 0.25 μm) Flow rate 1.5 mL / min Pressure 160 kPa Oven: 40℃ → 240℃ (7.5℃ / min) Post run: 10 min. In the above analysis, salt may be added to the sample as needed to promote the evaporation of aroma components into the headspace.

[0018] Furthermore, as long as the ratio [(a) / (b)] of (a) the concentration (ppb) of 2,3-butanedione to (b) the total concentration (ppb) of guaiacol and 4-ethylguaiacol described below is within a predetermined range, the concentration (ppb) of 2,3-butanedione per 1% Brix in the coffee extract of the present invention is not particularly limited, but is preferably 5.0 × 10 -3 ~1.0×10 5 ppb, more preferably 1.0 x 10 -2 ~8.0×10 4 ppb, and even more preferably 1.5 x 10 -2 ~5.0×10 4 If the concentration of (a) 2,3-butanedione in the coffee extract of the present invention is too low, the characteristic coffee aroma will be insufficient, whereas if the concentration of (a) 2,3-butanedione is too high, the overall balance of the coffee aroma will be lost, resulting in an unusual sweetness that is different from that of coffee.

[0019] 1-2. Guaiacol and 4-ethylguaiacol The coffee extract of the present invention contains guaiacol and 4-ethylguaiacol, which are components that contribute to the unpleasant taste characteristic of coffee. The total value of the peak area ratio of guaiacol and 4-ethylguaiacol in a coffee extract of the present invention, adjusted to a coffee solids concentration (Brix) of 1%, is not particularly limited as long as the ratio [(A) / (B)] described below is within a predetermined range, but is preferably 0.1 to 1.5, more preferably 0.1 to 0.5, and even more preferably 0.1 to 0.35. If the total value of the peak area ratio of (B) guaiacol and 4-ethylguaiacol in the coffee extract of the present invention is too low, the so-called "coffee flavor" due to bitterness and unpleasant tastes will be reduced, whereas if the total value of the peak area ratio of (B) guaiacol and 4-ethylguaiacol is too high, the unpleasant taste characteristic of coffee will be too strong.

[0020] Furthermore, as long as the ratio (a) / (b) described below is within a predetermined range, the total concentration (ppb) of guaiacol and 4-ethylguaiacol per 1% Brix in the coffee extract of the present invention is not particularly limited, but is preferably 1.5×10 -3 ~1.0×10 4 ppb, more preferably 2.0 x 10 -3 ~8.0×10 3 ppb, and even more preferably 3.0 x 10 -3 ~5.0×10 3 If the total concentration of (b) guaiacol and 4-ethylguaiacol in the coffee extract of the present invention is too low, the so-called "coffee flavor" resulting from bitterness and impurities will be reduced, whereas if the total concentration of (b) guaiacol and 4-ethylguaiacol is too high, the impurities specific to coffee will become too strong.

[0021] In one embodiment, the concentration (ppb) of guaiacol per 1% Brix in the coffee extract of the present invention is preferably 7.0 × 10 -4 ×~5.0×10 3 ppb, more preferably 1.0 x 10 -3 ~4.0×10 3 ppb, and even more preferably 1.5 x 10 -3 ~2.5×10 3 ppb.

[0022] In one embodiment, the concentration (ppb) of 4-ethylguaiacol per 1% Brix in the coffee extract of the present invention is preferably 7.0×10 -4 ~5.0×10 3 ppb, more preferably 1.0 x 10 -3 ~4.0×10 3 ppb, and even more preferably 1.5 x 10 -3 ~2.5×10 3 ppb.

[0023] 1-3. (A) The ratio of the peak area ratio of 2,3-butanedione to (B) the sum of the peak area ratios of guaiacol and 4-ethylguaiacol [(A) / (B)] In a coffee extract of the present invention, the coffee solids concentration (Brix) of which is adjusted to 1%, the ratio [(A) / (B)] of the peak area ratio of (A) 2,3-butanedione to the sum of the peak area ratios of (B) guaiacol and 4-ethylguaiacol is 7.0 or more, preferably 8.0 to 30.0, more preferably 9.0 to 20.0, and even more preferably 10.0 to 15.0. If this ratio [(A) / (B)] is too low, the off-flavor characteristic of coffee will be too strong, whereas if this ratio [(A) / (B)] is too high, the overall balance of the coffee aroma will be lost, resulting in an unusual sweetness that is different from coffee.

[0024] In one embodiment, the ratio [(a) / (b)] of (a) the concentration (ppb) of 2,3-butanedione to (b) the total concentration (ppb) of guaiacol and 4-ethylguaiacol in the coffee extract of the present invention is preferably 3.1 or more, more preferably 3.4 to 30.0, even more preferably 3.6 to 20.0, and particularly preferably 13.8 to 15.0.

[0025] 1-4. Coffee solids concentration The coffee solids concentration of the coffee extract of the present invention is not particularly limited, but is preferably 20 to 40% in Brix value, more preferably 25 to 37%, and particularly preferably 30 to 35%.

[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] 2. Beverages One aspect of the present invention is a beverage containing the aforementioned coffee extract. In the present invention, the aforementioned coffee extract can be used as a beverage as is, or can be concentrated or diluted as necessary to produce a beverage. The type of beverage is not particularly limited, but is preferably coffee, a coffee beverage, a coffee-infused soft drink, a coffee-infused soft drink (decaffeinated), or a coffee-infused carbonated beverage. These beverages are defined in Article 2 of the Fair Competition Code regarding the labeling of coffee beverages, etc.

[0028] If necessary, the beverage of the present invention may contain one or more additives such as bitterness suppressants, antioxidants, flavorings, various esters, organic acids, organic acid salts, inorganic acids, inorganic acid salts, inorganic salts, colorants, emulsifiers, preservatives, seasonings, acidulants, quality stabilizers, etc. Furthermore, when the beverage of the present invention is coffee, a coffee beverage, a coffee-containing soft drink, a coffee-containing soft drink (decaffeinated), or a coffee-containing carbonated beverage, it may be drunk black, or a sweetener such as milk or sugar may be added.

[0029] Furthermore, the beverage of the present invention can also be packaged as a container-packed beverage. The type of container is not particularly limited, and examples that can be used include ordinary packaging containers such as molded containers primarily made of polyethylene terephthalate (so-called PET bottles), metal cans, paper containers combined with metal foil or plastic film, and bottles.

[0030] Furthermore, when containerized beverages can be filled into containers such as metal cans and then heat sterilized, they can be produced under sterilization conditions stipulated in applicable laws and regulations (such as the Food Sanitation Act in Japan). For containers that cannot be retorted, such as PET bottles and paper containers, a method equivalent to the above can be used, such as sterilizing the beverage at high temperature for a short time using a plate heat exchanger, followed by cooling to a certain temperature and filling into containers.

[0031] 3. Coffee Extract Manufacturing Method The coffee extract of the present invention contains 2,3-butanedione, guaiacol, and 4-ethylguaiacol. The method for producing the coffee extract is not particularly limited, as long as the ratio [(A) / (B)] of (A) the peak area ratio of 2,3-butanedione to (B) the sum of the peak area ratios of guaiacol and 4-ethylguaiacol in a solution adjusted to a coffee solids concentration (Brix) of 1% is within the aforementioned range. In one embodiment, the coffee extract of the present invention contains 2,3-butanedione, guaiacol, and 4-ethylguaiacol. The method for producing the coffee extract is not particularly limited, as long as the ratio [(a) / (b)] of (a) the concentration (ppb) of 2,3-butanedione to (b) the sum of the concentration (ppb) of guaiacol and 4-ethylguaiacol in the coffee extract is within the aforementioned range. For example, the coffee extract can be produced by combining continuous multi-tube extraction and evaporation. Specifically, the coffee extract of the present invention can be produced through a) a first extraction step in which water at 70 to 120°C is supplied to a column packed with roasted and ground coffee beans to obtain a coffee extract, b) a second extraction step in which water at 125 to 150°C is supplied to the column packed with the roasted and ground coffee beans used in the first extraction step to obtain a coffee extract, c) a step of evaporating and concentrating the coffee extract obtained in the second extraction step, and d) a step of mixing the coffee extract obtained in the first extraction step with the evaporated and concentrated coffee extract.

[0032] To produce the coffee extract of the present invention, for example, a first extraction step can be used, in which a coffee extract is obtained by supplying water at 70 to 120°C, preferably 90 to 110°C, and more preferably 95 to 105°C, to a column packed with roasted and ground coffee beans. The column volume of the extraction column used in the first extraction step is not particularly limited, but is preferably 10 to 50 L, more preferably 15 to 30 L, and even more preferably 20 to 25 L.

[0033] Furthermore, the rate at which water is supplied per 1 L of column volume packed with roasted and ground coffee beans in the first extraction step is not particularly limited, but it is preferable to supply water at a flow rate of 1.0 to 10.0 kg / h per 1 L of column volume, more preferably at a flow rate of 2.0 to 7.0 kg / h per 1 L of column volume, and even more preferably at a flow rate of 3.0 to 5.0 kg / h per 1 L of column volume. Note that, in this specification, for example, supplying water at a flow rate of 1.0 to 10.0 kg / h per 1 L of column volume means supplying water to the column at a flow rate of 5.0 to 50.0 kg / h when the column volume used is 5 L.

[0034] The extraction rate of the extract obtained in the first extraction step is not particularly limited, but is preferably 10.0 to 23.0%, more preferably 12.0 to 21.0%, and even more preferably 14.0 to 20.0%.

[0035] In the first extraction step, from the viewpoint of obtaining a coffee extract rich in aroma components specific to coffee, it is preferable to connect multiple extraction columns filled with roasted and ground coffee beans in series and perform continuous extraction. The number of extraction columns in the first extraction step is preferably two or more, more preferably 2 to 10, and particularly preferably 3 to 6. When multiple extraction columns are used, coffee extracts can be extracted continuously by sequentially changing the extraction columns, for example, by supplying water at 70 to 120°C to a first extraction column filled with roasted and ground coffee beans to obtain a coffee extract, and then supplying the coffee extract obtained from the first extraction column to a second extraction column filled with roasted and ground coffee beans.

[0036] The volume of the extraction column used to produce the coffee extract of the present invention is not particularly limited, and the packing density of the roasted and ground coffee beans packed into the extraction column is also not particularly limited, but the amount of moistened roasted and ground coffee beans is preferably 0.20 to 0.50 kg / L (0.20 to 0.50 kg of moistened roasted and ground coffee beans per 1 L of column volume), more preferably 0.25 to 0.40 kg / L, and even more preferably 0.28 to 0.35 kg / L.

[0037] The amount of coffee extract collected from the extraction column is also not particularly limited, as it varies depending on the column volume and the amount of roasted and ground coffee beans packed in the column, but is preferably 0.05 to 0.50 kg per 1 L of column volume, more preferably 0.08 to 0.30 kg per 1 L of column volume, and particularly preferably 0.10 to 0.20 kg per 1 L of column volume. As mentioned above, the present invention also includes an embodiment in which multiple extraction columns packed with roasted and ground coffee beans are connected in series to perform continuous extraction, and the amount of coffee extract collected per 1 L of column volume is the amount collected per extraction column.

[0038] In order to produce the coffee extract of the present invention, a second extraction step can be included after the first extraction step, in which relatively high-temperature water is supplied to the column packed with roasted and ground coffee beans used in the first extraction step to obtain a coffee extract.

[0039] In the second extraction step, a column packed with the roasted and ground coffee beans used in the first extraction step is used. To produce the coffee extract of the present invention, the extraction temperature in the second extraction step is, for example, 125 to 150°C, preferably 125 to 140°C, and more preferably 125 to 135°C.

[0040] The column volume of the extraction column used in the second extraction step is not particularly limited, but is preferably 10 to 50 L, more preferably 15 to 30 L, and even more preferably 20 to 25 L.

[0041] Furthermore, in the second extraction step, it is preferable to maintain the temperature of the column packed with roasted and ground coffee beans throughout the extraction step, and the column temperature in the second extraction step is preferably 125 to 150°C, more preferably 125 to 140°C, and even more preferably 125 to 135°C.

[0042] In the second extraction step, the rate at which water is supplied per liter of column volume packed with roasted and ground coffee beans is not particularly limited, but it is preferable to supply water at a flow rate of 1.0 to 10.0 kg / h per liter of column volume, more preferably at a flow rate of 2.0 to 8.0 kg / h per liter of column volume, and even more preferably at a flow rate of 4.0 to 6.0 kg / h per liter of column volume.

[0043] The extraction rate of the coffee extract obtained in the second extraction step is not particularly limited, but is preferably 4.0 to 14.0%, more preferably 6.0 to 13.0%, and even more preferably 8.0 to 12.0%.

[0044] The coffee solids concentration of the coffee extract obtained in the second extraction step is not particularly limited, but is preferably 0.3 to 3.0% in Brix value, more preferably 0.5 to 2.5%, and even more preferably 1.0 to 2.0%.

[0045] Furthermore, the number of extraction columns used in the second extraction step is not particularly limited, but from the perspective of obtaining a high-concentration coffee extract, it is preferable to connect multiple extraction columns filled with roasted and ground coffee beans in series and perform continuous extraction. The number of extraction columns in the second extraction step is preferably two or more, more preferably 2 to 10, and particularly preferably 3 to 6. When multiple extraction columns are used, coffee extracts can be extracted continuously by sequentially changing the extraction columns, for example, by supplying water at 125 to 150°C to a first extraction column filled with roasted and ground coffee beans to obtain a coffee extract, and then supplying the coffee extract obtained from the first extraction column to a second extraction column filled with roasted and ground coffee beans.

[0046] The volume of the extraction column used in the second extraction step is not particularly limited. The packing density of the roasted and ground coffee beans packed into the extraction column is also not particularly limited, but the amount of moistened roasted and ground coffee beans is preferably 0.2 to 0.5 kg / L, more preferably 0.25 to 0.40 kg / L, and even more preferably 0.28 to 0.35 kg / L.

[0047] Furthermore, the amount of coffee extract collected from the extraction column in the second extraction step is not particularly limited, but is preferably 0.5 to 5.0 kg per 1 L of column volume, more preferably 0.8 to 3.0 kg per 1 L of column volume, and particularly preferably 1.0 to 1.5 kg per 1 L of column volume.

[0048] Furthermore, in order to produce the coffee extract of the present invention, a step of evaporating and concentrating the coffee extract obtained in the second extraction step can be included after the second extraction step.

[0049] The second extraction step uses a column filled with the roasted and ground coffee beans used in the first extraction step, so even when extraction is performed at a high temperature, the extraction efficiency of the coffee extract is not very high. Furthermore, when coffee is extracted at a high temperature, a large amount of impurity components is also included in the extract. Therefore, by evaporating and concentrating the coffee extract after the second extraction step, the concentration of the coffee extract can be increased and the impurity components can be volatilized, thereby suppressing the impurity in the coffee extract.

[0050] The heating temperature in the evaporation and concentration step is preferably 100 to 120°C, more preferably 105 to 115°C, and particularly preferably 108 to 112°C.

[0051] To produce the coffee extract of the present invention, a step of mixing the coffee extract obtained in the first extraction step with the coffee extract evaporated and concentrated after the second extraction step can be included. As described above, in the first extraction step, extraction at a low temperature (70 to 120°C) can be performed to obtain a coffee extract that maintains the good aroma and flavor unique to coffee. Furthermore, evaporative distillation after the second extraction step can obtain a highly concentrated coffee extract with reduced impurities. Therefore, by mixing the coffee extract obtained in the first extraction step with the coffee extract evaporated and concentrated after the second extraction step, a coffee extract with an enhanced coffee aroma and reduced impurities can be produced.

[0052] When producing the coffee extract of the present invention, the mixing ratio of the coffee extract obtained in the first extraction step and the coffee extract evaporated and concentrated after the second extraction step is not particularly limited, and the coffee extract obtained in the first extraction step and the coffee extract evaporated and concentrated after the second extraction step can be mixed as appropriate so that the coffee extract after mixing has the desired Brix value. In producing the coffee extract of the present invention, the coffee solids concentration of the coffee extract obtained by mixing the coffee extract obtained in the first extraction step and the coffee extract evaporated and concentrated after the second extraction step is preferably 20 to 40%, more preferably 25 to 37%, and particularly preferably 30 to 35%, in Brix value. [Example]

[0053] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0054] (1) Manufacturing of roasted and ground coffee beans Green coffee beans (Arabica, produced in Brazil) were roasted in a coffee roaster (manufactured by Probat) to an L value of 20. The roasted coffee beans were then ground in a roll mill (manufactured by GEA) to obtain roasted and ground coffee beans.

[0055] (2) Coffee extract production (i) First extraction step The roasted and ground coffee beans produced in (1) above were wetted with water (20 wt%) in an extraction column (GEA, volume 23 L) and then packed to a bean weight of 7.0 kg per column. Water at 100 °C was then supplied to the column at an extraction temperature of 100 °C and a flow rate of 80 kg / h, and extraction was performed to obtain a collected liquid volume of 3 kg. Next, the roasted and ground coffee beans were packed into a second column to obtain 7.0 kg of wetted beans per column, and two columns were connected together and similarly extracted to obtain a collected liquid volume of 3 kg. Furthermore, the roasted and ground coffee beans were packed into a third column to obtain 7.0 kg of wetted beans per column, and three columns were connected together and similarly extracted to obtain a collected liquid volume of 3 kg. The beans from the first column after three extractions were then sent to a process to collect a second extract. A new roasted and ground coffee beans was packed into a fourth column to obtain 7.0 kg of wetted beans per column, and three columns were connected together and similarly extracted to obtain a collected liquid volume of 3 kg. This extraction process was repeated (1 to 18 batches), and 10 to 18 batches of extracts that provided stable extraction rates and Brix values ​​were mixed to obtain the coffee extract after the first extraction process. The measurement results for each batch are shown in Table 1. The final coffee extract after the first extraction process had a liquid volume of 29.82 kg, a Brix of 29.21%, and an average extraction rate of 17.92%. [Table 1]

[0056] (ii) Second extraction step Up to four columns packed with the roasted and ground coffee beans used in the first extraction step (i) above were connected in series. Water at 130°C was then supplied to the columns at an extraction temperature of 130°C and a flow rate of 120 kg / h. Extraction was performed to obtain a 25 kg sample volume and a target extraction rate of 10%. After four extractions, the beans were discharged from the column, and new beans were loaded and used in the first extraction step. This extraction step was repeated (4 to 18 batches; batches 1 to 3 did not undergo the second extraction step because they had not yet completed the first extraction step). The extracts from 10 to 18 batches that provided stable extraction rates and Brix values ​​were mixed to obtain the coffee extract after the second extraction step. The measurement results for each batch are shown in Table 1. The final coffee extract after the second extraction step had a volume of 247.74 kg, a Brix of 1.80%, and an average extraction rate of 9.16%.

[0057] (iii) Evaporative distillation process Approximately 250 kg of the coffee extract after the second extraction step obtained in (ii) above was concentrated at a heating temperature of 110°C and an evaporation temperature of 50°C so that the coffee solids concentration in the extract would be 50%. The amount of liquid after evaporation and distillation of the coffee extract after the second extraction step obtained in (ii) above was 5.62 kg, and the Brix was 55.18%.

[0058] (iv) Preparation of sample coffee extract <Inventions> The invention product was prepared by mixing 1.0 kg of the coffee extract obtained in the first extraction step (i) above with 0.297 kg of the coffee extract obtained by evaporating and concentrating the coffee extract obtained in the second extraction step (iii) above. The volume of the invention product was 12.9 kg, and the Brix was 34.0%.

[0059] <Existing products 1-5> Five types of coffee extracts manufactured by other companies were used as existing products 1 to 5.

[0060] (3) Analysis of sample coffee extract The coffee solids concentration (Brix) of the coffee extracts of the invention product and existing products 1 to 5 was adjusted to 1%, and the peak area ratios of 2,3-butanedione, guaiacol, and 4-ethylguaiacol in the diluted coffee extracts were determined by gas chromatography-mass spectrometry using 10 ppb of borneol as an internal standard. The gas chromatography-mass spectrometry conditions were as follows: GC main unit: Agilent Technologies 7890A ·MS Detector: Agilent Technologies 5975C inert XL MSD with Triple-Axis Detector Pretreatment device: MultiPurpose Sampler MPS for GC Sample injection conditions: DHS (dynamic headspace) method Sample temperature: 80℃ Pressure 160kPa Septum purge flow rate: 3 mL / min Splitless Mode Column: HP-INNOWAX (length: 60 m, diameter: 0.250 mm, thickness: 0.25 μm) Flow rate 1.5 mL / min Pressure 160 kPa Oven: 40℃ → 240℃ (7.5℃ / min) Post run: 10 min.

[0061] Table 2 shows the peak area ratios of 2,3-butanedione, guaiacol, and 4-ethylguaiacol for the inventive product and existing products 1 to 5. Table 2 also shows the ratio (A / B) of the peak area ratio of 2,3-butanedione to the total peak area ratios of guaiacol and 4-ethylguaiacol. Table 3 also shows the concentrations of 2,3-butanedione, guaiacol, and 4-ethylguaiacol per 1% of the coffee solids concentration (Brix) of the coffee extracts for the inventive product and existing products 1 to 5. Table 3 also shows the ratio (a / b) of (a) the concentration of 2,3-butanedione to (b) the total concentration of guaiacol and 4-ethylguaiacol. As mentioned above, the coffee solids concentration (Brix) of the invented product is 34.0%, so the concentrations of 2,3-butanedione, guaiacol, and 4-ethylguaiacol in the invented product are 0.55 ppb, 0.05 ppb, and 0.09 ppb, respectively. [Table 2] [Table 3]

[0062] (4) Sensory evaluation test of coffee extract Next, the inventive product and existing products 1 to 5 produced in (2) above were each diluted with hot water to a Brix of 1% to obtain sample beverages for sensory evaluation testing. Each sample beverage was then subjected to a sensory evaluation by a panel of three experts. The sensory evaluation results for each sample beverage are shown in Table 4. [Table 4]

[0063] As shown in Tables 2 to 4, in the "invention product" in which the ratio [(A) / (B)] of the peak area ratio of (A) 2,3-butanedione to the sum of the peak area ratios of (B) guaiacol and 4-ethylguaiacol in the coffee extract is within the specified range, the sensory evaluation commented that the top aroma is sufficiently rich and extremely clean, indicating that the coffee aroma is enhanced and the off-flavors are suppressed. On the other hand, when [(A) / (B)] is below the range of the present invention, it was found that off-flavors and bitterness are perceived. This is also true for the "invention product" in which the ratio [(a) / (b)] of the concentration (ppb) of (a) 2,3-butanedione to the sum of the concentration (ppb) of (b) guaiacol and 4-ethylguaiacol in the coffee extract is within the specified range. It was shown that by setting the peak area ratio [(A) / (B)] and the concentration ratio [(a) / (b)] within a predetermined range, it is possible to provide a coffee extract that enhances the coffee's unique aroma and suppresses impurities. [Industrial Applicability]

[0064] The present invention provides a coffee extract in which the coffee-specific aroma is enhanced and impurities are suppressed, and therefore has high industrial applicability.

Claims

1. A coffee extract comprising 2,3-butanedione, guaiacol and 4-ethylguaiacol, the ratio [(a) / (b)] of (a) the concentration (ppb) of 2,3-butanedione to (b) the total concentration (ppb) of guaiacol and 4-ethylguaiacol in the coffee extract is 3.1 or more; The coffee solids concentration (Brix) is 20 to 40%, The concentration (ppb) of 2,3-butanedione per 1% Brix is ​​5.0×10 −3 to 1.0×10 5 , The concentration (ppb) of guaiacol per 1% of Brix is ​​7.0×10 −4 × to 5.0×10 3 ppb, The concentration (ppb) of 4-ethylguaiacol per 1% Brix is ​​7.0×10 −4 to 5.0×10 3 ppb. The coffee extract.

2. 2. The coffee extract according to claim 1, wherein the ratio [(a) / (b)] is 3.4 to 30.0.

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