Low-caffeine coffee concentrate

Abstract

Provided is a low-caffeine coffee concentrate for preparing a beverage, said beverage having a reduced caffeine content but yet maintaining the original flavor of coffee, in particular the deep richness and bitter after taste thereof, in an unimpaired state and, therefore, enabling a consumer to enjoy the authentic flavor of cafe latte.　In a coffee concentrate having a reduced caffeine content, the taste of coffee is enhanced and the authentic flavor of cafe latte is achieved without impairing the original flavor of coffee, by adjusting the content of caffeine and the content of acetic acid within a specific range.

Description

Low-caffeine coffee concentrate

[0001] The present invention relates to coffee concentrates, and in particular to low-caffeine coffee concentrates for dilution with milk to make a cafe latte.

[0002] Caffè latte is a drink that originated in Italy and is made by mixing espresso and milk. In recent years, American-style cafe bars have become popular, and caffè latte has also become established as a favorite beverage in Japan. Various coffee concentrates for caffè latte have been developed to allow people to easily make a luxurious cafe-like caffè latte at home (e.g., Non-Patent Documents 1 and 2).

[0003] However, the caffeine contained in coffee can stimulate the central nervous system and heart, as well as digestive organs such as the stomach and intestines, and so it tends to be avoided by people who are highly sensitive to these stimuli and health-conscious people. Therefore, decaffeinated coffee, which has reduced or eliminated caffeine, has been developed and is commercially available.

[0004] However, caffeine is one of the main flavor components of coffee, and reducing or eliminating it reduces the richness and bitterness characteristic of coffee, resulting in a loss of flavor. Therefore, various methods for improving the flavor of decaffeinated coffee have been proposed. Examples of methods for improving the flavor of decaffeinated coffee include adding theanine to decaffeinated coffee (Patent Document 1), incorporating ethyl isovalerate into decaffeinated coffee (Patent Document 2), incorporating potassium sulfate and / or potassium lactate into decaffeinated coffee (Patent Document 3), adding neutral amino acids such as valine, leucine, and isoleucine to decaffeinated coffee (Patent Document 4), and blending quercetin glycoside into low-caffeine coffee (Patent Document 5).

[0005] Japanese Patent Application Laid-Open No. 2004-105003 Republished No. 2011-108631 Japanese Patent Application Laid-Open No. 2015-50959 Japanese Patent Application Laid-Open No. 2009-254307 Japanese Patent Application Laid-Open No. 2017-143831

[0006] Suntory Beverage & Food International, news release, "New release of 'Boss Home Espresso Latte Mix'," [online], February 15, 2016, [Retrieved June 28, 2019], Internet <URL: https: / / www.suntory.co.jp / softdrink / news / pr / article / SBF0395.html> Coca-Cola Japan, news release, "'Georgia European Sarutahiko Coffee Supervised Coffee Base' Released Nationwide from Monday, April 9th," [online], April 2, 2018, [Retrieved June 28, 2019], Internet <URL: https: / / www.cocacola.co.jp / press-center / news-20180402-11>

[0007] Since coffee concentrate for making a cafe latte is diluted with milk before drinking, it is important that the richness (fullness) and bitterness characteristic of coffee are felt without diluting the flavor when mixed with milk. In particular, coffee concentrate with reduced caffeine content has a problem in that, because it contains a small amount of caffeine, a flavor component, diluting it with milk tends to impair the deep richness that is the original flavor of coffee and the bitterness characteristic of coffee felt in the aftertaste (also referred to as aftertaste bitterness in this specification).

[0008] To provide a low-caffeine coffee concentrate for preparing a beverage that has a reduced caffeine content but does not impair the inherent flavor and aroma of coffee, particularly the deep body and bitter aftertaste, and allows one to enjoy the flavor and aroma of authentic cafe latte.

[0009] The present inventors discovered that by adjusting the caffeine content and acetic acid content within specific ranges in a coffee concentrate with a reduced caffeine content, the coffee flavor is enhanced even when diluted with milk, and the coffee's inherent aroma and flavor, such as its deep body and bitter aftertaste, is not lost, resulting in the creation of an authentic cafe latte flavor, which led to the completion of the present invention. The present invention relates to, but is not limited to, the following: [1] A low-caffeine coffee concentrate for dilution at a dilution ratio of 3 to 6 to produce a beverage for consumption, the low-caffeine coffee concentrate satisfying the following (i) to (iv): (i) containing caffeine (A) at a concentration such that the caffeine concentration in the beverage produced by dilution is 0.1 to 10 mg / 100 g, (ii) containing acetic acid (B) at a concentration such that the acetic acid concentration in the beverage produced by dilution is 1 mg / 100 g or more, (iii) the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] is 0.7 to 25, and (iv) containing a coffee flavor. [2] The low-caffeine coffee concentrate according to [1], containing caffeine (A) at a concentration such that the caffeine concentration in the beverage produced by dilution is 0.5 to 6 mg / 100 g. [3] The low-caffeine coffee concentrate according to [1] or [2], containing a coffee extract, having a coffee solids concentration of 5 to 12 wt %. [4] The low-caffeine coffee concentrate according to [3], wherein the coffee solids concentration is 6 to 11% by weight. [5] The low-caffeine coffee concentrate according to [3] or [4], which contains a coffee extract and a coffee flavor. [6] The caffeine concentration relative to the coffee solids concentration (caffeine concentration / coffee solids concentration) is 2 x 10 －３ [7] The low-caffeine coffee concentrate according to any one of [3] to [5], wherein the caffeine concentration relative to the coffee solids concentration (caffeine concentration / coffee solids concentration) is 4 x 10 or less. －４[6] The low-caffeine coffee concentrate according to [6], which is the following: [8] The low-caffeine coffee concentrate according to any one of [1] to [7], which has a pH of 5.0 to 7.0. [9] The low-caffeine coffee concentrate according to [8], which has a pH of 5.3 to 6.0.

[10] The low-caffeine coffee concentrate according to any one of [1] to [9], which is for dilution with milk.

[11] A method for producing a low-caffeine coffee concentrate to be diluted at a dilution ratio of 3 to 6 to produce a beverage for consumption, the method comprising the steps of: (i) blending caffeine (A) at a concentration such that the caffeine concentration in the diluted beverage is 0.1 to 10 mg / 100 g; (ii) blending acetic acid (B) at a concentration such that the acetic acid concentration in the diluted beverage is 1 mg / 100 g or more; (iii) adjusting the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)]] to 0.7 to 25; and (iv) blending a coffee flavor.

[0010] By using the coffee concentrate with reduced caffeine content of the present invention, it is possible to prepare a beverage that can enjoy the flavor and aroma of authentic caffe latte despite the reduced caffeine content. The low-caffeine coffee concentrate of the present invention is highly convenient, as it can be easily prepared by simply mixing it with milk to create a caffe latte with a reduced caffeine content and an authentic flavor. Furthermore, the low-caffeine coffee concentrate of the present invention can be produced by adjusting the caffeine content and acetic acid content within specific ranges, which is advantageous in that it does not require special equipment and can be provided easily and inexpensively.

[0011] FIG. 1 is a diagram summarizing the results of Experiments 4 and 5.

[0012] (Coffee concentrate and low-caffeine coffee concentrate) In this specification, "coffee concentrate" refers to a liquid having a coffee flavor that is diluted to produce a beverage (hereinafter, sometimes simply referred to as a diluted beverage). Here, "liquid having a coffee flavor" refers to a liquid having an aroma reminiscent of coffee, and specifically refers to a liquid containing a coffee flavor. Coffee flavor will be described later.

[0013] Furthermore, in this specification, the term "low-caffeine coffee concentrate" refers to a coffee concentrate in which the caffeine has been reduced or removed, and more specifically refers to a liquid having a coffee flavor that is to be diluted and made into a drink, and that contains caffeine at a concentration that results in a caffeine concentration in the drink after dilution of 0.1 to 10 mg / 100 g.

[0014] The dilution ratio for diluting the low-caffeine coffee concentrate of the present invention may be set appropriately according to the consumer's preferences, but is preferably 3 to 6 times by volume. Specifically, for example, a dilution ratio of 3 times by volume means adding 2 volumes of dilution medium to 1 volume of low-caffeine coffee concentrate. In this specification, the dilution ratio is based on a volume ratio.

[0015] The present invention is based on the discovery that adjusting the caffeine content and acetic acid content in a low-caffeine coffee concentrate within specific ranges enhances the coffee flavor of a beverage produced by diluting the low-caffeine coffee concentrate. The coffee flavor enhancement effect of acetic acid will be described later; this enhances the flavor of small amounts of caffeine. Therefore, the low-caffeine coffee concentrate of the present invention must have a caffeine concentration of at least 0.1 mg / 100 g after dilution, and from the perspective of reducing caffeine, a concentration of 0.1 to 10 mg / 100 g is preferred. To further enhance the effects of the present invention, the low-caffeine coffee concentrate of the present invention preferably contains caffeine at a concentration that results in a diluted beverage of 0.3 to 8 mg / 100 g, more preferably a caffeine concentration that results in a diluted beverage of 0.5 to 6 mg / 100 g, and particularly preferably a caffeine concentration that results in a diluted beverage of 0.8 to 3 mg / 100 g. From another perspective, the low-caffeine coffee concentrate of the present invention has a caffeine concentration relative to the coffee solids concentration contained therein (caffeine concentration / coffee solids concentration) of 2×10 －３ Preferably, it is 4×10 or less. －４It is more preferable that the coffee solids concentration is equal to or less than the above. The coffee solids concentration will be described later.

[0016] The caffeine content of the low-caffeine coffee concentrate of the present invention can be calculated by multiplying the caffeine content in the diluted beverage by the dilution ratio. For example, if the coffee concentrate is diluted 4 times, a "coffee concentrate containing caffeine at a concentration such that the diluted beverage has a caffeine concentration of 0.1 to 10 mg / 100 g" refers to a coffee concentrate containing 0.4 to 40 mg / 100 g of caffeine. Based on this, the low-caffeine coffee concentrate of the present invention, which is diluted 3 to 6 times to produce a beverage for consumption, preferably contains 0.3 to 60 mg / 100 g of caffeine, more preferably 0.9 to 48 mg / 100 g of caffeine, more preferably 1.5 to 36 mg / 100 g of caffeine, and even more preferably 2.4 to 18 mg / 100 g of caffeine.

[0017] The caffeine content in the coffee concentrate and the caffeine content in the diluted beverage can be measured by a known method using high performance liquid chromatography (HPLC), for example.

[0018] In the low-caffeine coffee concentrate of the present invention, the method for adjusting the caffeine content to the desired level is not particularly limited. For the purpose of reducing the caffeine content in the coffee concentrate, a coffee extract obtained from coffee beans from which caffeine has been removed or reduced may be used, or caffeine may be removed or reduced from the coffee extract. Examples of methods for removing or reducing caffeine include methods of removing caffeine from refined green coffee beans, methods using coffee beans from which caffeine has been removed by breeding techniques and genetic engineering techniques, methods of selectively removing caffeine by immersing green coffee beans in a solvent such as an organic solvent, water, or supercritical carbon dioxide, and methods of adsorbing and removing caffeine from the coffee extract using activated carbon, ion exchange resins, or the like. These caffeine removal or reduction methods may be used alone or in combination.

[0019] On the other hand, the caffeine content can be increased to adjust the caffeine content in the low-caffeine coffee concentrate to a desired amount, and in such cases, a caffeine preparation acceptable for food and beverages can be added.

[0020] (Acetic Acid) By adjusting the caffeine content and acetic acid content of the low-caffeine coffee concentrate of the present invention to fall within specific ranges, the coffee flavor is enhanced even in beverages produced by diluting the low-caffeine coffee concentrate, and the beverages have a deep body and bitter aftertaste that is equal to or greater than the flavor and aroma of beverages produced by diluting coffee concentrates with no reduced caffeine. Among the acidic components, acetic acid specifically has the effect of enhancing the flavor of caffeine.

[0021] The acetic acid content in the coffee concentrate of the present invention is adjusted so that the acetic acid concentration in the diluted beverage is 1 mg / 100 g or more, preferably 2 mg / 100 g or more, more preferably 3 mg / 100 g or more, and even more preferably 6 mg / 100 g or more.

[0022] Acetic acid is a volatile acid, and its pungent acidic odor is known to adversely affect flavor. Therefore, in beverages that have not been treated to reduce caffeine, it has been proposed to reduce the acetic acid content of coffee beans in order to improve flavor (see, for example, JP 2011-97832 A and JP 2005-11396 A). In the present invention, a predetermined amount of acetic acid is added to a concentrated solution of low-caffeine coffee that has been treated to reduce the caffeine content. If the acetic acid content is too low, the desired effect of enhancing the caffeine flavor may not be achieved.

[0023] The taste-enhancing effect of caffeine increases depending on the concentration of acetic acid. However, if the concentration of acetic acid in the diluted beverage is greater than 25 mg / 100 g, not only will the taste-enhancing effect plateau, but the odor of acetic acid may also inhibit the desired effect. Therefore, the upper limit of the acetic acid content in the coffee concentrate of the present invention is preferably 25 mg / 100 g or less of the diluted beverage, more preferably 20 mg / 100 g or less, and even more preferably 18 mg / 100 g or less.

[0024] The acetic acid content of the low-caffeine coffee concentrate of the present invention can be calculated, similarly to the caffeine content, by multiplying the acetic acid content in the diluted beverage by the dilution ratio. For example, a "coffee concentrate containing acetic acid at a concentration such that the acetic acid concentration in the diluted beverage is 1 mg / 100 g or more" means a coffee concentrate containing acetic acid at a concentration of 4 mg / 100 g or more when the coffee concentrate is diluted 4 times. Based on this, a low-caffeine coffee concentrate of the present invention for dilution at a dilution ratio of 3 to 6 times to produce a beverage for consumption preferably contains 3 mg / 100 g or more of acetic acid, more preferably 6 mg / 100 g or more of acetic acid, more preferably 9 mg / 100 g or more of acetic acid, and even more preferably 18 mg / 100 g or more of acetic acid. Furthermore, the low-caffeine coffee concentrate of the present invention, which is diluted at a dilution ratio of 3 to 6 times to produce a beverage for drinking, preferably contains 150 mg / 100 g or less of acetic acid, preferably 120 mg / 100 g or less of acetic acid, and more preferably 108 mg / 100 g or less of acetic acid.

[0025] The acetic acid content in the coffee concentrate and the acetic acid content in the diluted beverage can be measured by a method using high performance liquid chromatography (HPLC), a common method for analyzing organic acids.

[0026] To achieve the desired effect, the concentration ratio of caffeine (A) to acetic acid (B), [(B) / (A)], is also important in the low-caffeine coffee concentrate of the present invention. Specifically, [(B) / (A)] is 0.7 to 25, preferably 1 to 20, more preferably 3 to 15, and particularly preferably 5 to 15. In particular, for a low-caffeine coffee concentrate containing caffeine at a concentration such that the caffeine concentration in the diluted beverage is 0.5 to 6 mg / 100 g, it is preferable to adjust [(B) / (A)] to 0.7 to 25, 1 to 20, 3 to 15, or 5 to 15.

[0027] The acetic acid used in the low-caffeine coffee concentrate of the present invention may be any acetic acid or salt thereof that can be added to foods and beverages. Furthermore, crude extracts, extracts, or refined products from natural products containing acetic acid may also be blended into the coffee concentrate.

[0028] (Coffee Flavor) The low-caffeine coffee concentrate of the present invention contains a coffee flavor. The coffee flavor used in the present invention includes coffee flavorings as food additives that can be added to beverages, as well as extracts of roasted coffee beans containing coffee aroma components (also referred to as "coffee extract" in this specification). A low-caffeine coffee concentrate containing a coffee flavoring and a coffee extract is a preferred embodiment of the present invention.

[0029] The inventors have discovered that a certain amount of acetic acid can enhance the richness and bitter aftertaste of coffee, as well as its nutty aroma. Therefore, when the coffee flavor in the low-caffeine coffee concentrate of the present invention contains a coffee flavoring, it is preferable that the coffee flavoring contain a nutty aroma component. Examples of nutty aroma components include pyrazines such as 2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine, and 2,3,5-trimethylpyrazine. 2,3,5-trimethylpyrazine is particularly suitable because it has a roasted nutty aroma and significantly enhances the effects of the present invention.

[0030] The coffee flavor used in the present invention is not particularly limited, and commercially available products can be freely used as appropriate. Those skilled in the art may use the terms "fragrance" to refer to the aroma of roasted and ground coffee, "aroma" to refer to the aroma of extracted coffee, and "flavor" to refer to the aroma of coffee when sipped in the mouth, but in this specification, the term "coffee flavor" also includes flavors with coffee fragrance and coffee aroma.

[0031] When a coffee flavor is blended into the low-caffeine coffee concentrate of the present invention, the amount of coffee flavor blended can be appropriately set taking into consideration the potency of the flavor used, the dilution ratio of the coffee concentrate, etc., but is usually about 0.01 to 5.0 wt %, preferably about 0.03 to 4.0 wt %, more preferably about 0.05 to 3.0 wt %, and even more preferably about 0.1 to 1.5 wt %, of the coffee concentrate.

[0032] The coffee flavor in the low-caffeine coffee concentrate of the present invention may contain a coffee extract. As used herein, the term "coffee extract" refers to a solution obtained by extracting roasted and ground coffee beans with water or hot water, and also includes coffee extract obtained by concentrating the coffee extract, and a solution obtained by drying the coffee extract and adjusting the amount of the dried solid matter to an appropriate amount with water or hot water.

[0033] The type of coffee beans used for the coffee extract is not particularly limited, but examples include Blue Mountain, High Mountain, Jamaica, Crystal Mountain, Guatemalan Antigua, Colombian Supremo, Mocha Jara, Mocha Matari, Kilimanjaro, Toraja, Kalosi, Gayo Mountain, Mandheling, Brazil, and Hawaiian Kona. Coffee bean species include Arabica and Robusta. One type of coffee bean may be used, or multiple types may be blended.

[0034] These green beans can be roasted in a coffee roaster and used as a raw material for the coffee extract. For example, the green coffee beans can be roasted by placing them inside a rotating drum and heating them from below with a gas burner or the like while rotating and stirring the drum. The roasting level of such coffee beans is approximately 14 to 30 in terms of L value. Since the low-caffeine coffee concentrate of the present invention is used to prepare cafe lattes, it is preferable that the coffee beans have a taste reminiscent of espresso. Since the darker the coffee beans are roasted, the more bitter and rich the flavor becomes, so dark-roasted beans (approximately 14 to 22 in terms of L value, preferably approximately 15 to 20) are typically used for espresso. It is also preferable to use dark-roasted beans as the roasted coffee beans used as a raw material for the coffee extract to be used in the low-caffeine coffee concentrate of the present invention. Here, the L value is an index representing the degree of roasting of coffee and is the value measured using a colorimeter to measure the brightness of ground roasted coffee beans (black is represented by 0 and white is represented by 100).

[0035] There are no limitations on the method for extracting coffee extract from roasted coffee beans. For example, roasted coffee beans are ground into coarse, medium, or fine grinds, and then extracted for 10 seconds to 30 minutes using water or hot water (0 to 200°C). The extraction method can be appropriately selected from known methods such as drip, siphon, boiling, jet, and continuous column methods. In the case of a column method, for example, coffee beans are placed in a column-type extractor, and hot or cold water is supplied to the extractor. In this case, multi-stage extraction can also be performed. Here, multi-stage extraction refers to an extraction method using an apparatus in which multiple independent extraction towers are connected in series by piping. Multi-stage extraction can produce an extract having a high coffee solids concentration equivalent to that of a concentrate without a concentration step, making it a preferred extraction method from the perspective of flavor and aroma.

[0036] The liquid containing the coffee flavor can be used as a coffee concentrate (hereinafter also referred to as coffee concentrate base) that serves as the base for the low-caffeine coffee concentrate of the present invention, and the caffeine concentration, acetic acid concentration, and concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] in the coffee concentrate base can be adjusted to fall within predetermined ranges to produce the low-caffeine coffee concentrate of the present invention.

[0037] For example, the low-caffeine coffee concentrate of the present invention may be prepared by using the above-mentioned coffee extract as a coffee concentrate base as is, and adjusting the caffeine concentration, acetic acid concentration, and the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] in the coffee concentrate base to fall within predetermined ranges.

[0038] Alternatively, the low-caffeine coffee concentrate of the present invention may be prepared by using the above-mentioned coffee extract as is as a coffee concentrate base, adjusting the caffeine concentration, acetic acid concentration, and the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] in the coffee concentrate base to fall within predetermined ranges, and further adding a coffee flavoring as necessary.

[0039] When the low-caffeine coffee concentrate of the present invention contains a coffee extract, the coffee solids concentration in the coffee extract is preferably 5 to 12% by weight. When the low-caffeine coffee concentrate of the present invention contains a coffee extract, the coffee extract is preferably contained in the low-caffeine coffee concentrate so that the coffee solids concentration in the low-caffeine coffee concentrate is 5 to 12% by weight. A coffee extract having a coffee solids concentration of 5 to 12% by weight can be used as a coffee concentrate base as is, or diluted as appropriate, to produce a low-caffeine coffee concentrate having a coffee solids concentration of 5 to 12% by weight.

[0040] Here, in this specification, the term "coffee solids" refers to, for example, the weight (g) of the soluble solids in the coffee extract, determined from the sugar refractometer reading (Brix) at 20°C. Specifically, the sugar refractometer reading (Brix) of the coffee extract is measured using a sugar refractometer (such as the Atago RX-5000), and the weight (g) of the coffee solids is calculated by multiplying this by the amount (g) of the coffee extract used for the measurement. Furthermore, the coffee solids concentration in this specification refers to the concentration (wt%) based on the weight (g) of the coffee solids determined above. Specifically, the coffee solids concentration (wt%) in the coffee extract can be determined by calculating the percentage of the weight of the coffee solids determined above relative to the weight of the coffee extract. The coffee solids concentration in the low-caffeine coffee concentrate of the present invention can be determined in a similar manner. The Brix value may also be used as the coffee solids concentration in the coffee extract or concentrate of the present invention.

[0041] When the coffee solids concentration in the low-caffeine coffee concentrate of the present invention is 5% by weight or more (preferably 6% by weight or more), the original taste of coffee is easily perceived even when it is used at a dilution ratio of, for example, 3 to 6 times with milk, and when the above-mentioned specified amount of acetic acid is added, the original deep body and bitterness of coffee can be further enhanced. Furthermore, from the viewpoint of flavor and aroma, the upper limit of the coffee solids concentration in the low-caffeine coffee concentrate of the present invention is preferably 12% by weight, more preferably 11% by weight, and particularly preferably 10% by weight.

[0042] (Other Components) In order to ensure the remarkable effects of the present invention, the pH of the low-caffeine coffee concentrate of the present invention is preferably 5.0 to 7.0, more preferably 5.0 to 6.0, and even more preferably 5.3 to 6.0. To adjust the pH, common pH adjusters such as sodium bicarbonate and sodium hydroxide can be used.

[0043] In addition to the above-mentioned components, sweeteners (sucrose, isomerized sugar, glucose, fructose, lactose, maltose, aspartame, acesulfame K, sucralose, stevia, etc.), antioxidants (sodium L-ascorbate, etc.), emulsifiers (sucrose fatty acid esters, sorbitan acid esters, polyglycerin fatty acid esters, etc.), acidulants, flavorings, etc. may be appropriately blended, provided that the effects of the present invention are not impaired.

[0044] (Dilution Medium) Any liquid acceptable for food and beverage use may be used as the dilution medium for diluting the low-caffeine coffee concentrate of the present invention, but milk is preferably used.

[0045] The low-caffeine coffee concentrate of the present invention is characterized by having a caffeine content and an acetic acid content within a predetermined range, thereby enhancing the coffee flavor of the beverage produced by diluting with a dilution medium, and providing a deep, full-bodied coffee flavor and bitter aftertaste that is equal to or even greater than the flavor and aroma of a beverage produced by diluting a coffee concentrate with a non-reduced caffeine content. Therefore, even when mixed with a large amount of milk, the low-caffeine coffee concentrate of the present invention can produce a beverage that has a rich coffee flavor and a strong bitterness (especially a bitter aftertaste) that is not overpowered by the milk. Thus, the low-caffeine coffee concentrate of the present invention is suitable for use as a concentrate for dilution with milk. Here, the term "milk" as used herein refers to a white liquid in which proteins and fats exist as fine colloidal particles, which would otherwise dilute the flavor and aroma of coffee. This term includes animal milks such as cow's milk, as well as plant-based milks such as soy milk, almond milk, rice milk, and coconut milk.

[0046] (Method for producing low-caffeine coffee concentrate) From another aspect, the present invention also relates to a method for producing a low-caffeine coffee concentrate for preparing a beverage that has a reduced caffeine content but does not impair the original coffee aroma and flavor, particularly the deep body and bitter aftertaste, and that allows the flavor and flavor of authentic cafe latte to be enjoyed.

[0047] Specifically, the present invention relates to a method for producing a low-caffeine coffee concentrate to be diluted at a dilution ratio of 3 to 6 to produce a beverage for consumption, the method comprising the steps of: (i) blending caffeine (A) at a concentration such that the caffeine concentration in the diluted beverage is 0.1 to 10 mg / 100 g; (ii) blending acetic acid (B) at a concentration such that the acetic acid concentration in the diluted beverage is 1 mg / 100 g or more; (iii) adjusting the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)]] to 0.7 to 25; and (iv) blending a coffee flavor.

[0048] The present invention will be described in more detail below with reference to experimental examples, but the present invention is not limited thereto. Furthermore, in this specification, unless otherwise specified, numerical ranges are stated to include their endpoints.

[0049] In the present examples, the amounts of each component in the beverage were measured by the following methods.

[0050] <Measurement of caffeine concentration> The caffeine concentration was determined by diluting each sample 10-fold (w / w) with mobile phase A, filtering it through a membrane filter (Cellulose Acetate 0.45 μm, manufactured by ADVANTEC), and injecting it into HPLC. The HPLC measurement conditions were as follows: Column: TSK-gel ODS-80TsQA (4.6 mmφ x 150 mm, Tosoh Corporation) Mobile phase: A: water: trifluoroacetic acid = 1000:0.5 B: acetonitrile: trifluoroacetic acid = 1000:0.5 Flow rate: 1.0 ml / min Column temperature: 40°C Gradient conditions: Hold 100% of solution A for 5 minutes from the start of analysis, 7.5% of solution B from 5 to 10 minutes, 10.5% of solution B from 10 to 20 minutes, hold 10.5% of solution B from 20 to 32 minutes, 26.3% of solution B from 32 to 45 minutes, 75.0% of solution B from 45 to 46 minutes, hold 75.0% of solution B from 46 to 51 minutes, 0% of solution B from 51 to 52 minutes Solution B was held at 0% from 52 to 58 minutes. Injection volume: 5.0 μl Detection wavelength: 280 nm Retention time: 19.3 minutes Standard substance: caffeine (anhydrous) (Nacalai Tesque, Inc.)

[0051] <Measurement of Acetic Acid Concentration> Each sample beverage was mixed with 0.5% perchloric acid, diluted with ion-exchanged water, filtered through a membrane filter (Cellulose Acetate 0.45 μm, manufactured by ADVANTEC), and injected into HPLC for quantification. The HPLC measurement conditions were as follows: Model: LC-20AD (Shimadzu Corporation) Detector: Electrical conductivity meter CDD-10AVP (Shimadzu Corporation) Column: Shim-pack SCR-102H x 2 φ8 mm x 300 mm (Hitachi Chemical Co., Ltd.) Mobile phase: 5 mmol / L aqueous p-toluenesulfonic acid solution Reaction solution: An aqueous solution in which p-toluenesulfonic acid was diluted with water to a p-toluenesulfonic acid concentration of 5 mmol / L, and which contained 20 mmol / L Bis-Tris and 0.1 mmol / L EDTA Flow rate: Mobile phase 0.8 ml / min, reaction solution 0.8 ml / min Column temperature: 45°C Injection volume: 10 μl

[0052] [Experiment 1] The relationship between the acetic acid concentration and the strength of body, bitterness, and aroma was investigated for beverages produced by diluting low-caffeine coffee concentrate with milk.

[0053] First, low-caffeine coffee concentrate samples were prepared. Caffeine extract (Shiratori Pharmaceutical Co., Ltd.) and commercially available coffee flavoring agents containing pyrazines were blended with ion-exchanged water to achieve the final concentrations shown in the "Concentrate" row of Table 1. Various amounts of powdered acetic acid (Nippon Synthetic Chemical Industry Co., Ltd.) were then added to prepare low-caffeine coffee concentrates with the various acetic acid concentrations shown in the "Concentrate" row of Table 1. When the pH was below 5.0, sodium bicarbonate was added to adjust the pH to 5.0-5.5. These low-caffeine coffee concentrates with different acetic acid concentrations were diluted 5-fold with milk (coffee flavor liquid:milk ratio 1:4) to obtain cafe latte-like beverages with caffeine concentrations of 2 mg / 100 g and coffee solids concentrations of 0%.

[0054] A sensory evaluation of this cafe latte-like beverage was conducted by a trained panel of five experts. Using a sample without added acetic acid (Sample 1-1) as a control, the evaluation assessed whether the beverages approximated the taste of a cafe latte, i.e., a beverage made by mixing espresso and milk. Specifically, each panel member individually evaluated the coffee's richness (the coffee's richness must be clearly perceived), bitterness (the coffee's bitterness must be clearly perceived), and aroma (the coffee aroma must be clearly perceived). A rating of "Good" was given when all five panel members rated the beverage as more similar to a cafe latte than the control; a rating of "Average" was given when three to four panel members rated the beverage as more similar to a cafe latte than the control; and a rating of "Poor" was given when two or fewer panel members rated the beverage as more similar to a cafe latte than the control (including when all panel members rated the beverage as no different from the control).

[0055] The results are shown in Table 1. When acetic acid was contained at a concentration of 1 mg / 100 g or more in the cafe latte flavored beverage obtained by diluting with a large amount of milk (5 times dilution), in addition to the smooth, creamy mouthfeel that is unique to milk, the coffee taste (richness, bitterness) and aroma (particularly the nutty aroma) were enhanced depending on the concentration of acetic acid, resulting in a flavor similar to that of a cafe latte.

[0056]

[0057] [Experiment 2] The relationship between the caffeine concentration and the acetic acid concentration when coffee concentrate was diluted with milk was investigated.

[0058] Coffee concentrates were prepared in the same manner as in Experiment 1, except that caffeine was added to the concentrations shown in the "Concentrate" row of Tables 2-1 to 2-4. These coffee concentrates were diluted 5-fold with milk, and sensory evaluations were carried out in the same manner as in Experiment 1, using samples without added acetic acid (Samples 2-1, 2-4, 2-7, 2-10, 2-13, 2-16, 2-19, and 2-22) for each caffeine concentration as controls.

[0059] The results are shown in Table 2. When the caffeine concentration in the beverage obtained by dilution was less than 0.1 mg / 100 g (Samples 2-2, 2-3, 2-5, and 2-6), the enhancement of the coffee taste and aroma by acetic acid was not confirmed. On the other hand, when the caffeine concentration in the beverage obtained by dilution exceeded 10 mg / 100 g (Samples 2-20 and 2-21), the beverage had a sufficient coffee flavor without the addition of acetic acid, and therefore the enhancement of the coffee taste and aroma by acetic acid was not confirmed. This demonstrates that a caffeine concentration of 0.1 to 10 mg / 100 g of the diluted beverage is necessary to achieve the effects of the present invention.

[0060]

[0061]

[0062]

[0063]

[0064] [Experiment 3] The effect of pH on the caffeine taste-enhancing effect of acetic acid was investigated. Phosphoric acid and sodium bicarbonate were added appropriately to Samples 1-5 (pH 5.5) from Experiment 1 to prepare low-caffeine coffee concentrates with pHs ranging from 4.0 to 7.5. Controls without added acetic acid were prepared for each pH, ​​and the low-caffeine coffee concentrates and the control products were diluted 5-fold with milk in the same manner as in Experiment 1 and subjected to sensory evaluation.

[0065] When the pH of a low-caffeine coffee concentrate was below 5.0, it caused aggregation and precipitation when mixed with milk. This aggregation likely made it difficult to perceive the coffee taste and aroma, and the addition of acetic acid did not significantly enhance the caffeine flavor. On the other hand, when the pH of a low-caffeine coffee concentrate exceeded 7.0, the overall flavor of the beverage was dull, making it difficult to perceive the coffee or milk flavors. Even with the addition of acetic acid, several panelists reported an improved coffee flavor, but did not report the same significant effect as with low-caffeine coffee concentrates with a pH of 5.0-6.0 or 5.3-6.0.

[0066] [Experiment 4] A low-caffeine coffee concentrate prepared by blending coffee extract and coffee flavor was diluted with milk, and the relationship between the acetic acid concentration and the strength of body, bitterness, and aroma was investigated.

[0067] First, a low-caffeine coffee extract was prepared. Specifically, commercially available roasted coffee beans (L value ≈18) whose caffeine content had been reduced using supercritical carbon dioxide extraction were used, and steam treatment was performed in the same manner as in Example 3 of JP2005 / 011396A to obtain low-caffeine steam-treated roasted coffee beans. These roasted beans were ground to a medium grind and placed in a multi-stage column-type extraction device. Hot water was added to perform multi-stage extraction, resulting in a coffee extract with an extract Brix (i.e., coffee solids concentration in the extract) of 12%. This coffee extract was diluted with water to obtain a coffee extract with a coffee solids concentration of 5%. These coffee extracts with a coffee solids concentration of 5% were used as coffee concentrate bases to prepare low-caffeine coffee concentrates with a coffee solids concentration of 5%.

[0068] Specifically, this coffee extract with a coffee solids concentration of 5% was blended with the acetic acid used in Experiment 1 and a coffee flavor containing pyrazines (a flavor different from that used in Experiment 1) according to the formulation shown in Table 3-1. The pH was adjusted to 5.3 to 6.0 using sodium bicarbonate to prepare low-caffeine coffee concentrates (Samples 4-1 to 4-7) with the contents of each component shown in the "Concentrate" row of Table 3-1. As a control, a low-caffeine control coffee concentrate was prepared by adding 9 mg / 100 g of caffeine and 0.3 g / 100 g of the coffee flavor to ion-exchanged water, without the coffee extract, but with the same caffeine and coffee flavor concentrations. The low-caffeine coffee concentrates and low-caffeine control coffee concentrates thus prepared, each with different acetic acid concentrations, were diluted four-fold with milk (coffee concentrate:milk = 1:3) to obtain a caffe latte-like beverage.

[0069] Additionally, 20 mg / 100 g of the caffeine used in Experiment 1 was added to a coffee extract with a coffee solids concentration of 5%, and the above-mentioned coffee flavor was added to prepare high-caffeine coffee concentrates (Samples 4-8 to 4-10) having the component contents shown in the "Concentrate" row of Table 3-2. A high-caffeine control coffee concentrate was also prepared as a control, lacking the coffee extract but with the same caffeine and coffee flavor concentrations. The high-caffeine coffee concentrates and high-caffeine control coffee concentrates thus prepared, each with a different acetic acid concentration, were diluted four-fold with milk (coffee concentrate:milk = 1:3) to obtain a caffe latte-like beverage.

[0070] A sensory evaluation of these cafe latte-like beverages was carried out in the same manner as in Experiment 1, comparing them with a control beverage having the same caffeine concentration and coffee flavor concentration.

[0071] The results are shown in Tables 3-1 and 3-2. A low-caffeine coffee concentrate containing a low concentration of caffeine, resulting in a caffeine concentration in the beverage obtained upon dilution within the range of 1 to 10 mg / 100 g (2.3 mg / 100 mg), contained acetic acid (B) at a concentration such that the concentration of acetic acid (B) in the beverage obtained upon dilution was 1 mg / 100 g or greater, and the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] was adjusted to 0.7 to 11, resulting in a cafe latte that clearly conveyed the strength and bitterness of the coffee and evoked a mellow coffee like espresso. Combined with the results in Table 2, it was shown that a concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] in the range of 0.7 to 25 is preferable.

[0072]

[0073]

[0074] [Experiment 5] The coffee extract with a coffee solids concentration of 12% prepared in Experiment 4 was mixed with an appropriate amount of water to prepare coffee extracts with coffee solids concentrations of 2%, 9%, and 12%. These coffee extracts with coffee solids concentrations of 2%, 9%, and 12% were used as coffee concentrate bases to prepare low-caffeine coffee concentrates with coffee solids concentrations of 2%, 9%, and 12%, respectively. Specifically, coffee flavor and various concentrations of acetic acid were blended with these coffee extracts with different coffee solids concentrations in the same manner as in Experiment 4 to obtain the formulations shown in Tables 4-1 and 4-2. Low-caffeine coffee concentrates with different coffee solids concentrations and different acetic acid concentrations were obtained. These low-caffeine coffee concentrates were diluted four-fold with milk and subjected to sensory evaluation in the same manner as in Experiment 1.

[0075] The results are shown in Tables 4-1 and 4-2. Even in beverages containing caffeine derived from coffee extract, in coffee concentrates containing a low concentration of caffeine, such as 1 to 10 mg / 100 g of the diluted beverage, by adding acetic acid (B) at a concentration such that the acetic acid content in the diluted beverage is 1 mg / 100 g or more, and by adjusting the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] to be in the range of 0.7 to 25, particularly in the range of 3 to 15, a cafe latte was obtained that had a strong coffee flavor and bitterness that was reminiscent of a mellow coffee like espresso.

[0076] Figure 1 shows a summary of the results of Experiments 4 and 5. In the figure, the ● marks indicate beverages that the expert panel evaluated as having a particularly rich and bitter coffee flavor, and they were evaluated as cafe latte-style beverages that leave a lingering coffee aftertaste even after drinking it, and leave a pleasant rich coffee flavor and bitterness in the mouth for a long time.

[0077]

[0078]

Claims

1. A low-caffeine coffee concentrate for diluting at a dilution ratio of 3 to 6 to produce a beverage for drinking, said low-caffeine coffee concentrate satisfying the following (i) to (iv): (i) containing caffeine (A) at a concentration such that the caffeine concentration in the beverage produced by said dilution is 0.1 to 10 mg / 100 g, (ii) containing acetic acid (B) at a concentration such that the acetic acid concentration in the beverage produced by said dilution is 1 mg / 100 g or more, (iii) the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] is 0.7 to 25, and (iv) containing a coffee flavor.

2. A low-caffeine coffee concentrate according to claim 1, comprising a coffee extract, the low-caffeine coffee concentrate having a coffee solids concentration of 5-12% by weight.

3. A low-caffeine coffee concentrate according to claim 1 or 2, having a pH of 5.0 to 7.

0.

4. A low-caffeine coffee concentrate according to any one of claims 1 to 3 for dilution with milk.

5. A method for producing a low-caffeine coffee concentrate to be diluted at a dilution ratio of 3 to 6 to produce a beverage for drinking, comprising the steps of: (i) blending caffeine (A) at a concentration such that the caffeine concentration in the diluted beverage is 0.1 to 10 mg / 100 g; (ii) blending acetic acid (B) at a concentration such that the acetic acid concentration in the diluted beverage is 1 mg / 100 g or more; (iii) adjusting the concentration ratio of caffeine (A) to acetic acid (B) [(B) / (A)] to 0.7 to 25; and (iv) blending a coffee flavor.