JP7729348B2 - Diluted coffee drinks - Google Patents

Description

The present invention relates to a dilution coffee beverage that is diluted with water or the like at the time of consumption and a method for producing the same.

Coffee is a popular, everyday beverage. To make it easier to enjoy coffee, numerous powdered instant coffees are available on the market, which can be consumed by dissolving them in water or other liquids, as well as coffee drinks for dilution, which can be consumed by diluting them in water or other liquids. However, the components responsible for the coffee's distinctive flavor and aroma are lost or altered during the powdering process for instant coffee and the concentration process for coffee drinks for dilution. As a result, instant coffee and coffee drinks for dilution have the problem of being inferior in flavor and aroma to regular coffee made from freshly roasted coffee beans.

Dilutable coffee beverages are expected to produce highly palatable coffee beverages with excellent taste and aroma, even when diluted with water, by using a high-concentration coffee extract containing a rich and balanced amount of flavor and aroma components as a raw material. However, in industrially mass-produced dilutable coffee beverages, solids extraction from roasted coffee beans is typically performed using a countercurrent multistage continuous extractor with multiple extraction towers connected in series to extract larger amounts of coffee solids, due to raw material costs. In particular, to hydrolyze and extract the polysaccharides in the roasted coffee beans, extraction is performed under high-temperature, high-pressure conditions with a water supply temperature of 170-190°C. The resulting high-concentration coffee extract is further concentrated as needed, and sweeteners and flavorings are added as needed to achieve the desired flavor, resulting in the production of a dilutable coffee beverage.

Several methods for improving the taste and aroma of coffee beverages obtained by diluting a coffee beverage for dilution have been reported. For example, Patent Document 1 describes how adjusting the turbidity of a coffee beverage for dilution when the coffee solids concentration is adjusted to 1.0 wt % and the value obtained by dividing the caffeine concentration by the coffee solids concentration within a specific range allows the characteristic coffee aroma and flavor to be maintained even when diluted with hot water, water, or milk. Patent Document 2 also describes how adjusting the content ratio of pyrazines and guaiacols within a specific range can improve the flavor and aroma of a coffee solution for dilution. It further describes how a coffee extract can be separated into a concentrate and a fraction by distillation, the concentrate treated with a porous adsorbent, and then the porous adsorbed concentrate and the fraction can be mixed to prepare a coffee beverage for dilution with a content ratio of pyrazines and guaiacols within a specific range.

JP 2017-163864 A International Publication No. 2010/125770

The present invention aims to provide a coffee beverage for dilution that can be easily prepared by simply diluting it with a liquid such as water to produce a coffee beverage with a strong coffee aroma and a clean aftertaste, as well as a method for producing the coffee beverage for dilution.

As a result of intensive research to solve the above-mentioned problems, the inventors discovered that by adjusting the coffee solids concentration of the coffee beverage to be diluted, the ratio of the 2,3,5-trimethylpyrazine content to the furaneol content, and the potassium content per coffee solids so that they each fall within a specific range, the coffee aroma and crispness of the coffee beverage obtained by dilution can be improved, leading to the completion of the present invention.

[1] A coffee beverage for dilution according to a first aspect of the present invention is characterized in that the coffee solids concentration is 7.0 to 15.0% by mass, the ratio of the 2,3,5-trimethylpyrazine content to the furaneol content is 0.8 or more, and the potassium content per coffee solids is 4.5 to 5.5% by mass.
[2] In the coffee beverage for dilution according to [1] above, the caffeine content per solid coffee content as a raw material is preferably 2.5 to 4.8% by mass.
[3] The coffee beverage for dilution according to [1] or [2] above is preferably a packaged beverage.
[4] The coffee beverage for dilution according to any one of [1] to [3] above, which is diluted 5 to 10 times with an edible aqueous solution at the time of consumption.
[5] A method for producing a coffee extract according to a second aspect of the present invention is a method for producing a coffee extract from roasted coffee beans by high-temperature, high-pressure extraction, characterized in that the water supply temperature in the high-temperature, high-pressure extraction is 145 to 160°C, the coffee extract has a coffee solids concentration of 7.0 to 15.0 mass%, a ratio of the 2,3,5-trimethylpyrazine content to the furaneol content of 0.8 or more, and a potassium content per coffee solids of 4.5 to 5.5 mass%.
[6] In the method for producing a coffee extract according to [5] above, it is preferable that the caffeine content of the coffee extract relative to the coffee solids is 2.5 to 4.8% by mass.
[7] A method for producing a coffee beverage for dilution according to a third aspect of the present invention involves producing a coffee extract by the coffee extract production method described in [5] or [6] above, and using the resulting coffee extract as a raw material to produce a coffee beverage for dilution.

By diluting the coffee beverage for dilution according to the first aspect of the present invention with water or the like, a coffee beverage with a strong coffee aroma and a clean aftertaste can be provided.
Furthermore, the coffee beverage for dilution can be easily produced by the method for producing a coffee extract according to the second aspect of the present invention and the method for producing a coffee beverage for dilution according to the third aspect of the present invention.

<Dilutable coffee drink>
In the present invention and this specification, the term "coffee beverage for dilution" refers to a composition that can be diluted with a liquid such as water or milk to prepare a coffee beverage. Generally, packaged coffee beverages that are mass-produced in factories and consumed as is without dilution have a coffee solids content (Brix %) of about 1.0 to 2.0%. A coffee beverage for dilution is diluted with water, milk, or the like to a coffee solids content of about 1.0 to 2.0% and then consumed, and is usually produced to have a coffee solids content of about 5.0 to 20%.

The coffee beverage for dilution according to the present invention is characterized by having a coffee solids concentration of 7.0 to 15.0% by mass, a ratio of the 2,3,5-trimethylpyrazine content to the furaneol content ([2,3,5-trimethylpyrazine content (ppm)]/[furaneol content (ppm)], hereinafter sometimes referred to as the "T/F value") of 0.8 or greater, and a potassium content per coffee solids of 4.5 to 5.5% by mass. By adjusting the coffee solids amount, T/F value, and potassium content within the above ranges and diluting the coffee solids to approximately 1.0 to 2.0%, a coffee beverage with a strong coffee aroma and a clean aftertaste can be obtained.

The coffee beverage for dilution according to the present invention has a coffee solids concentration of 7.0 to 15.0% by mass and is consumed after being diluted to the desired strength with an edible aqueous solution such as water. For example, the coffee beverage for dilution according to the present invention can be diluted 5 to 10 times with an edible aqueous solution at the time of consumption.

[Coffee solids]
In the present invention and this specification, "coffee solids" refers to soluble solids extracted from coffee beans. The coffee beverage for dilution according to the present invention is made from a coffee extract extracted from roasted coffee beans, and the coffee solids of the coffee beverage for dilution according to the present invention are solids (g) derived from the coffee extract used as the raw material.

In the present invention and this specification, the coffee solids concentration (mass%) of a coffee extract is the Brix value (mass%) measured using a Brix meter (refractometer) at 20°C. Hereinafter, the "coffee solids concentration (mass%) of a coffee extract" may be referred to as the "Brix value of the coffee extract." The coffee solids concentration of a coffee beverage for dilution can be calculated, for example, using the following formula:

[Coffee solids concentration of coffee beverage for dilution (mass%)] = [Brix value of raw coffee extract (mass%)] x [amount of raw coffee extract (L)] / [amount of coffee beverage for dilution (L)]

If the coffee solids of the coffee extract used as an ingredient contain solids from ingredients other than the coffee extract, the coffee solids of the coffee beverage to be diluted will be the solids of the coffee beverage to be diluted minus the total amount of solids of the ingredients other than the coffee extract. In this case, the coffee solids concentration of the coffee beverage to be diluted can be calculated, for example, using the following formula:

[Coffee solids concentration of coffee drink to be diluted (mass%)] = [Solids concentration of coffee drink to be diluted (mass%)] - [Total amount of solids of ingredients other than coffee extract (g)] / [Amount of coffee drink to be diluted (L)] x 100

In addition, the coffee solids content (g) of the coffee beverage for dilution according to the present invention can be calculated by multiplying the coffee solids concentration (mass %) of the coffee beverage for dilution by the amount of the coffee beverage for dilution (L).

[T/F value]
The coffee beverage for dilution according to the present invention has a T/F value of 0.8 or greater, preferably 0.8 to 5.0, and more preferably 0.8 to 3.0. 2,3,5-Trimethylpyrazine and furaneol are both aroma components contained in extracts of roasted coffee beans. 2,3,5-Trimethylpyrazine is a relatively volatile aroma component and is easily lost by heat treatment, etc. Furaneol, on the other hand, is highly water-soluble and relatively resistant to degradation during the production process. The coffee beverage for dilution according to the present invention has a relatively high T/F value of 0.8 or greater, minimizing loss of highly volatile aroma components. Therefore, by diluting the coffee beverage for dilution according to the present invention, a coffee beverage can be obtained that has a well-balanced sweet aroma necessary for delicious coffee and the fragrant aroma characteristic of regular coffee.

2,3,5-trimethylpyrazine and furaneol in diluted coffee beverages and coffee extracts can both be measured using gas chromatography-mass spectrometry (GC/MS).

[potassium]
The potassium concentration in the raw water is very low, and the potassium in a coffee extract is mainly derived from roasted coffee beans. However, the amount of potassium in roasted coffee beans is generally not affected by the type of coffee beans or the roasting conditions. In other words, the potassium content per coffee solid in a coffee extract ([amount of potassium in the coffee extract (g)] / [amount of coffee solid in the coffee extract (g)] x 100) is affected by the extraction efficiency ([amount of extracted coffee solid (g)] / [amount of roasted coffee beans used for extraction (g)]). The higher the extraction efficiency, the lower the amount of potassium relative to the coffee solid, and the lower the extraction efficiency, the higher the amount of potassium relative to the coffee solid.

The coffee beverage for dilution according to the present invention has a potassium content of 4.5 to 5.5% by mass per coffee solids. Coffee extracts extracted under extraction conditions that result in a potassium content of 4.5 to 5.5% by mass per coffee solids have sufficient extracted aroma components, but only a small amount of components that cause off-flavors. Therefore, coffee beverages for dilution produced using such coffee extracts as a raw material have a strong coffee-like aroma and little off-flavors, and by diluting them, a refreshing coffee beverage with little off-flavors and a good coffee-like aroma is obtained.

Potassium in dilute coffee drinks and coffee extracts can be measured using an atomic absorption spectrometer.

[Caffeine]
The caffeine in a coffee extract is derived from roasted coffee beans, and the amount of caffeine in roasted coffee beans generally varies depending on the type of coffee beans. In other words, the caffeine content per coffee solid in a coffee extract ([amount of caffeine in coffee extract (g)]/[amount of coffee solid in coffee extract (g)]×100) can be adjusted to within a desired range by appropriately adjusting the type and amount of raw coffee beans used.

Caffeine is the main component responsible for coffee's characteristic bitterness; if the caffeine concentration is too low, the coffee flavor weakens, while if it's too high, the aftertaste tends to be too bitter. The intensity of the bitter aftertaste also affects the cleanness of the aftertaste. Too much caffeine and a strong bitterness results in a dull aftertaste. A coffee extract with a caffeine content of 2.5 to 4.8% by mass per coffee solids in the coffee extract has a desirable bitterness for coffee and a clean aftertaste. Therefore, by diluting a coffee beverage for dilution produced using such a coffee extract as a raw material, a coffee beverage with a coffee-like bitterness and a clean aftertaste can be obtained.

Caffeine in dilute coffee beverages and coffee extracts can be measured using HPLC (high performance liquid chromatography).

The dilution coffee beverage of the present invention can be produced by adding other ingredients to the coffee extract as needed to achieve the desired product design. These other ingredients can be selected from additives commonly added to coffee beverages. Specific examples include sweeteners, flavorings, antioxidants, pH adjusters, thickeners, emulsifiers, etc.

Sweeteners include sugars such as sugar, sucrose, oligosaccharides, glucose, and fructose; sugar alcohols such as sorbitol, maltitol, erythritol, xylitol, and reduced starch syrup; high-intensity sweeteners such as aspartame, acesulfame potassium, sucralose, neotame, advantame, and saccharin; and stevia.

Flavors include coffee flavoring, milk flavoring, etc.

Examples of antioxidants include vitamin C (ascorbic acid), vitamin E (tocopherol), BHT (dibutylhydroxytoluene), BHA (butylhydroxyanisole), sodium erythorbate, propyl gallate, sodium sulfite, sulfur dioxide, chlorogenic acid, and catechin.

Examples of pH adjusters include citric acid, succinic acid, acetic acid, lactic acid, malic acid, and tartaric acid. Examples include organic acids such as gluconic acid, inorganic acids such as phosphoric acid, potassium carbonate, sodium hydrogen carbonate (sodium bicarbonate), and carbon dioxide.

Thickeners include starch hydrolysates such as dextrin, sugars such as maltose and trehalose, indigestible dextrin, dietary fiber such as pectin, guar gum and carrageenan, and proteins such as casein.

Examples of emulsifiers include glycerin fatty acid ester-based emulsifiers such as monoglycerides, diglycerides, organic acid monoglycerides, and polyglycerin esters; sorbitan fatty acid ester-based emulsifiers such as sorbitan monostearate and sorbitan monooleate; propylene glycol fatty acid ester-based emulsifiers such as propylene glycol monostearate, propylene glycol monopalmitate, and propylene glycol oleate; sugar ester-based emulsifiers such as sucrose stearate, sucrose palmitate, and sucrose oleate; and lecithin-based emulsifiers such as lecithin and lecithin enzyme hydrolysates.

When producing the coffee beverage for dilution according to the present invention, the coffee extract used as the raw material may be subjected to various processes in advance, such as concentration, dilution, and impurity removal. The coffee extract can be concentrated using commonly used concentration methods, such as thermal concentration, freeze concentration, or membrane concentration using reverse osmosis or ultrafiltration membranes. Impurity removal can be performed using processes commonly used to remove insoluble matter from beverages, such as filtration or centrifugation. These processes may also be performed on the coffee extract after other ingredients have been added and mixed.

The coffee beverage for dilution according to the present invention is preferably distributed on the market as a packaged beverage. The container and method for filling the coffee beverage for dilution can be appropriately selected from those commonly used in the manufacturing process of packaged coffee beverages. Examples of such containers include cans, plastic containers, paper containers, and glass bottles. Furthermore, filling into the container can be carried out in the air or under a nitrogen gas atmosphere.

When the coffee beverage for dilution according to the present invention is a packaged beverage, the coffee beverage for dilution, which has been pre-sterilized, may be aseptically filled into a sterilized container and sealed, or the container filled with the coffee beverage for dilution and sealed may be sterilized, or hot-pack filling may be performed, in which the heated coffee beverage for dilution is filled into a container while still hot and sealed.

The sterilization process can be selected from among the sterilization processes typically used in the production of coffee beverages, such as heat sterilization, retort sterilization, and ultraviolet irradiation sterilization. For example, heat sterilization may be low-temperature sterilization at 100°C or below, or high-temperature sterilization at 100°C or above. For example, a method of heating to a high temperature for a short period of time and then filling the product into a container that has been sterilized under aseptic conditions (UHT sterilization) is preferred.

The coffee beverage for dilution according to the present invention is diluted, for example, 5 to 10 times to achieve the desired strength when consumed. The aqueous solution used for dilution is not particularly limited as long as it is an edible aqueous solution, and examples include water, milk, low-fat milk, skim milk, and vegetable milk. Furthermore, the temperature of the aqueous solution used for dilution is not particularly limited, and may be any temperature between 0 and 100°C.

Plant-based milks include legume milk and nut milk. Legume milks include soy milk and peanut milk. Nut milks include almond milk, walnut milk, pistachio milk, hazelnut milk, cashew milk, and pecan milk. These milks and plant-based milks can be produced using conventional methods.

<Method of producing coffee extract>
For example, the coffee beverage for dilution according to the present invention can be produced by using a coffee extract as a raw material that has a coffee solids concentration of 7.0 to 15.0% by mass, a T/F value of 0.8 or more, and a potassium content per coffee solids of 4.5 to 5.5% by mass. A coffee extract having a coffee solids concentration, T/F value, and potassium content per coffee solids within the above ranges can be produced, for example, by a method of producing a coffee extract from roasted coffee beans by high-temperature, high-pressure extraction.

The roasted coffee beans used as a raw material in the coffee extract manufacturing method of the present invention are not particularly limited as long as they are roasted, and the type and origin of the coffee beans are not particularly limited. Examples of types of coffee beans include Arabica, Robusta, and Liberica, and blends of these beans are also acceptable. Examples of origins of coffee beans include Brazil, Colombia, Tanzania, Mocha, Kilimanjaro, Mandheling, Blue Mountain, Guatemala, Vietnam, and Indonesia.

The method for roasting coffee beans is not particularly limited, and can be selected from methods commonly used for roasting coffee beans, such as direct flame roasting, hot air roasting, far-infrared roasting, charcoal roasting, and microwave roasting. Roasting conditions can be selected appropriately to achieve the desired roast level. Furthermore, the roasted coffee beans used as the raw material may be those obtained by roasting green coffee beans, or those obtained by further roasting roasted coffee beans. Furthermore, they may also be those obtained by roasting green beans that have been subjected to known pre-roasting treatment.

It is preferable that the roasted coffee beans are ground before extraction. The equipment used to grind the roasted coffee beans is not particularly limited as long as it can grind them to the desired particle size. For example, grinding equipment such as a cutter mill, hammer mill, jet mill, impact mill, or Willey grinder can be used. The degree of grinding is not particularly limited, and roasted coffee beans of various shapes, such as coarse, medium, medium, medium-fine, and fine grinds, can be used.

The type and amount of roasted coffee beans used as raw materials are preferably selected appropriately and blended as needed so that the caffeine content of the resulting coffee extract falls within the desired range. For example, by keeping the ratio (mixing rate) of Robusta coffee beans to the total amount of raw roasted coffee beans relatively low and increasing the mix rate of Arabica or Liberica coffee beans, the caffeine content per coffee solid can be kept to approximately 2.5 to 4.8% by mass.

High-temperature, high-pressure extraction of roasted coffee beans can be carried out using a countercurrent multi-stage continuous extractor, which is commonly used in the production of instant coffee and other products. Roasted coffee beans are placed in multiple serially connected extraction towers, each filled with water as the extraction solvent, and the beans are continuously extracted under high pressure. There are no particular limitations on the water used as the extraction solvent; for example, tap water, distilled water, ion-exchanged water, natural water, etc. can be selected and used as appropriate.

The feed water temperature of the water supplied to the most upstream extraction tower is preferably 145 to 160°C. When producing instant coffee, the feed water temperature is generally 170 to 190°C. However, in the coffee extract production method of the present invention, by setting the feed water temperature to a relatively low temperature, the loss of aroma components is suppressed and the T/F value is increased. Furthermore, compared to feed water temperatures below 145°C, the amount of components extracted per coffee solids that may cause off-flavors in roasted coffee beans can be relatively reduced. Therefore, the coffee extract production method of the present invention produces a coffee extract with a high T/F value, rich in aroma components, but low in off-flavor components.

In the method for producing a coffee extract according to the present invention, the extraction ratio ([amount of coffee extract (g)] / [amount of raw roasted coffee beans (g)]) is not particularly limited. The smaller the extraction ratio, the more sufficiently components that are relatively easy to extract, such as aroma components, are extracted, but the amount of components that are relatively difficult to extract is reduced, resulting in a smaller total amount of extracted solids and a higher potassium content per coffee solid. On the other hand, if the extraction ratio is too high, the total amount of extracted solids tends to increase and the potassium content per coffee solid tends to decrease. Since this allows for a coffee extract of sufficient strength while minimizing the amount of extracted off-flavor components, it is preferable to set the extraction ratio at around 1.5 to 3.0.

The coffee extract obtained by high-temperature, high-pressure extraction is diluted with water or concentrated as needed to achieve the desired Brix value. The concentration method can be any of the methods listed above.

The coffee beverage for dilution according to the present invention can be produced by further adding various additives to the resulting coffee extract, as needed. Such additives include sweeteners, flavorings, antioxidants, pH adjusters, thickeners, emulsifiers, etc. Examples of such additives include those listed above.

In addition, the sterilization process and filling process into containers of the obtained diluted coffee beverage can be carried out using the methods mentioned above.

The present invention will now be described in more detail with reference to the following examples and reference examples, but the present invention is not limited to these examples. In the following examples, unless otherwise specified, "%" means "% by mass" and "ppm" means "ppm by mass."

[Brix value]
The Brix value of the coffee extract was measured for the sample at 20°C using a Brix meter (RX-5000α-plus, manufactured by ATAGO).

[Quantitative determination of furaneol and 2,3,5-trimethylpyrazine]
The contents of furaneol and 2,3,5-trimethylpyrazine in coffee extract were measured using a GC/MS system equipped with a thermal desorption pretreatment device under the following measurement conditions: The area ratio of furaneol to 2,3,5-trimethylpyrazine was determined using the quantitative ions described below, and the concentrations were calculated based on the obtained area ratio.

Pretreatment device: MPS2 XL TDU/CIS4 (manufactured by Gestel)
Purge conditions: Trapping purge 100 mL/min (35 min, 3500 mL)
Purge temperature: 80°C
Injection port conditions: 20°C (0.5 min) → 260°C (12°C/sec, hold for 10 min)
Analyzer GC: 7890B (manufactured by Agilent Technology)
Analyzer MS: 5977B (manufactured by Agilent Technology)
Column: Inertcap WAX-HT (60 m x 0.25 mm, film thickness 0.25 μm, manufactured by GL Science)
Quantitative ion (2,3,5-trimethylpyrazine): m/z = 122
Quantitative ion (furaneol): m/z = 128
Temperature conditions: 60°C (0 minutes) ⇒ 250°C (5°C/minute, hold for 15 minutes)
Carrier gas flow rate: He 2 mL/min Interface temperature: 250°C
Ion source temperature: 230°C

[Potassium determination]
The potassium content in the coffee extract was measured using an atomic absorption spectrometer under the following measurement conditions.

Apparatus: Atomic absorption spectrophotometer Z-2300 (Hitachi High-Tech Science Corporation)
Hollow cathode lamp: Hollow Cathode Lamp K (manufactured by Hitachi High-Tech Science Corporation)
Standard substance: Potassium standard solution K100 (Fujifilm Wako Pure Chemical Industries, Ltd.)

[Quantitative determination of caffeine]
The caffeine content in the coffee extract was measured by HPLC under the following measurement conditions.

HPLC equipment: 2695 Separations Module (manufactured by Waters), 2996 Photodiode Array Detector (manufactured by Waters)
Column: TSKgel ODS-80Ts (4.6 mm ID x 15 cm, 5 μm)
Column temperature: 40°C
Mobile phase A: 1% (v/v) acetic acid, 5% (v/v) acetonitrile
Mobile phase B: 1% (v/v) acetic acid, 50% (v/v) acetonitrile Detection: UV 274 nm
Injection volume: 50μL
Flow rate: 1 mL/min Gradient program: 10 min (A: 90%, B: 10%) → 10.1 min (A: 0%, B: 100%) → 18 min (A: 0%, B: 100%) → 18.1 min (A: 90%, B: 10%) → 25 min (A: 90%, B: 10%)
Standard substance: caffeine (Wako Pure Chemical Reagent)

[Example 1]
A coffee extract (Test Plots 1 to 10) was prepared from raw roasted coffee beans (a blend of Arabica and Robusta) using a countercurrent multistage continuous extractor and water as the extraction solvent, with the Arabica blending ratio (the proportion of Arabica in the total raw roasted coffee beans: %), water supply temperature, and extraction ratio shown in Tables 1 and 2. The analytical results of each coffee extract obtained are shown in Tables 1 and 2.

Each coffee extract was used as a dilution coffee beverage, which was then diluted with water to a Brix value of 1.8% to prepare a coffee beverage. Sensory evaluation of each coffee beverage was conducted by five in-house expert panelists for the strength of the coffee aroma and the clean aftertaste. Specifically, the strength of the coffee aroma and the clean aftertaste were scored using a visual analogue scale (VAS), with a minimum score of 1.0 and a maximum score of 5.0. A higher score indicates a stronger coffee aroma and a cleaner aftertaste. The average score of all panelists was used as the evaluation score for each coffee beverage. A score of 4.4 or higher was considered to indicate improvement in both the strength of the coffee aroma and the clean aftertaste. The evaluation results are shown in Tables 1 and 2.

Comparing test plots 1 to 8, the higher the inlet water temperature, the smaller the T/F value, and the lower the potassium content per coffee solids. Furthermore, the diluted coffee beverages from test plots 2 to 6, in which the inlet water temperature was 145 to 160°C, had both a coffee aroma intensity and a clean aftertaste of 4.4 or higher, resulting in highly palatable coffee beverages with excellent coffee aroma and a clean aftertaste. In contrast, the coffee extract from test plot 1, in which the inlet water temperature was 138°C, had a high potassium content per solids of 5.9%, and the diluted coffee beverage had a slightly weak aftertaste. The coffee extracts from test plots 7 and 8, in which the inlet water temperature was 170 to 180°C, had a small T/F value of 0.5 or less, and the diluted coffee beverages had a slightly weak coffee aroma. More specifically, in test plots 1 to 8, it was observed that the larger the T/F value, the stronger the coffee aroma tended to be, and the smaller the potassium content per coffee solids, the better the clean aftertaste tended to be.

On the other hand, the coffee extract from Test Group 9, which contained a low proportion of Arabica beans and a high proportion of Robusta beans in the raw roasted coffee beans, had a high caffeine content per coffee solids. The coffee beverage obtained by diluting this coffee had a good coffee aroma, but a strong bitterness and a weak aftertaste. Furthermore, despite the coffee beverage from Test Group 9 containing only 10% Arabica beans, it received a high coffee aroma intensity rating of 4.4. This is presumably due to the water supply temperature of 145°C and the slightly low extraction ratio of 1.5, which resulted in good extraction of aroma components. Furthermore, these extraction conditions resulted in a relatively high potassium content per coffee solids, which presumably extracted a relatively large amount of components that cause unpleasant flavors, resulting in a weak aftertaste.

Furthermore, when comparing Test Plot 5 and Test Plot 10, which were the same in terms of water supply temperature and Arabica blend ratio, but differed only in extraction ratio, the coffee beverage obtained from Test Plot 10 was inferior to the coffee beverage obtained from Test Plot 5 in both coffee aroma intensity and clean aftertaste. This is presumably because the T/F value of the coffee extract from Test Plot 10 was small at 0.7, and the extraction ratio was too high, disrupting the aroma balance.

Claims (7)

The coffee solids concentration is 7.0 to 15.0% by mass,
the ratio of the content of 2,3,5-trimethylpyrazine to the content of furaneol is 0.8 or more;
A coffee beverage for dilution, characterized in that the potassium content per coffee solid content is 4.5 to 5.5 mass %. A coffee beverage for dilution as described in claim 1, wherein the caffeine content per coffee solid is 2.5 to 4.8% by mass. A coffee beverage for dilution according to claim 1 or 2, which is a packaged beverage. A coffee beverage for dilution according to any one of claims 1 to 3, which is diluted 5 to 10 times with an edible aqueous solution when consumed. A method for producing a coffee extract from roasted coffee beans by high-temperature, high-pressure extraction,
The feed water temperature in the high-temperature, high-pressure extraction is 145 to 160°C,
The coffee extract has a coffee solids concentration of 7.0 to 15.0% by mass, a ratio of the 2,3,5-trimethylpyrazine content to the furaneol content of 0.8 or more, and a potassium content per coffee solids content of 4.5 to 5.5% by mass. A method for producing a coffee extract as described in claim 5, wherein the caffeine content of the coffee extract per coffee solids is 2.5 to 4.8% by mass. A coffee extract is produced by the method for producing a coffee extract according to claim 5 or 6,
A method for producing a coffee beverage for dilution, in which the obtained coffee extract is used as a raw material to produce a coffee beverage for dilution.