JP7686401B2 - Coffee drinks - Google Patents

Description

The present invention relates to a coffee beverage. More specifically, the present invention relates to a coffee beverage and a method for producing the same, and a method for reducing unpleasant flavors in a coffee beverage.

Coffee beverages have a unique flavor and aroma and are widely enjoyed as a luxury beverage. The flavor and aroma preferred in coffee beverages are determined from various viewpoints, such as richness, aftertaste, and balance of sourness and sweetness. Conventionally, research and development of coffee beverages according to desired flavors has been conducted.
For example, Patent Document 1 discloses a coffee beverage containing specific amounts of 2-methylfuran, guaiacol, and propanal from the viewpoint of obtaining a strong and good coffee flavor and a good aftertaste. Patent Document 2 discloses a coffee extract containing specific ratios of furfural and at least one selected from guaiacol, 4-ethylguaiacol, and 4-vinylguaiacol from the viewpoint of obtaining a rich, fragrant roasted aroma and a good, crisp aftertaste.

JP 2019-146526 A JP 2011-125283 A

On the other hand, regarding the richness of coffee beverages, although it is known that increasing the degree of roasting of coffee beans is a way to enhance the richness, there has been a tendency for off-flavors to be produced when the degree of roasting is increased to increase the richness.
Therefore, the inventors focused on the aroma components contained in coffee in order to achieve both improved richness and reduced unpleasant flavors, and as a result of conducting new intensive research, they unexpectedly discovered that when the ratio of caffeine concentration to chlorogenic acid concentration exceeds a certain level, specific aroma components can effectively reduce unpleasant flavors while improving the richness of a coffee beverage.

According to the present invention,
When the ratio of the caffeine concentration to the chlorogenic acid concentration (caffeine concentration/chlorogenic acid concentration) is A, the concentration of guaiacol is B (ppb), and the concentration of 4-ethylguaiacol is C (ppb),
(i) A is 4.0 or more;
(ii) A coffee beverage is provided, wherein B/A is 85-300 and/or C/A is 45-200.

Further, according to the present invention,
1. A method for producing a coffee beverage, comprising the steps of:
When the ratio of the caffeine concentration to the chlorogenic acid concentration (caffeine concentration/chlorogenic acid concentration) is A, the concentration of guaiacol is B (ppb), and the concentration of 4-ethylguaiacol is C (ppb),
(i) A is 4.0 or more;
(ii) adjusting the B/A to 85 to 300 and/or the C/A to 45 to 200.

Further, according to the present invention,
A method for reducing unpleasant flavors in a coffee beverage, comprising:
When the ratio of the caffeine concentration to the chlorogenic acid concentration (caffeine concentration/chlorogenic acid concentration) is A, the concentration of guaiacol is B (ppb), and the concentration of 4-ethylguaiacol is C (ppb),
(i) A is 4.0 or more;
(ii) A method for reducing unpleasant flavors in a coffee beverage is provided, the method comprising the step of adjusting the B/A to 85 to 300 and/or the C/A to 45 to 200.

The present invention provides technology for coffee beverages that can simultaneously improve richness and reduce unpleasant flavors.

The following is a detailed description of an embodiment of the present invention. In this specification, the notation "a to b" in the description of a numerical range means a or more and b or less, unless otherwise specified.

In this specification, "body" refers to the richness and flavor felt when drinking a coffee beverage, and "off-flavors" refers to the unpleasant, bitter taste that lingers on the tongue when taking a sip of a coffee beverage.

The concentration (content) of chlorogenic acid and the concentration (content) of caffeine in a coffee beverage can be quantified by high performance liquid chromatography (HPLC). The concentration (content) of aroma components in a coffee beverage can be measured by GC-MS.

<Coffee drinks>
In the coffee beverage of the present embodiment, when the ratio of the caffeine concentration to the chlorogenic acid concentration (caffeine concentration/chlorogenic acid concentration) is A, the guaiacol concentration is B (ppb), and the 4-ethylguaiacol concentration is C (ppb),
(i) A is 4.0 or more;
(ii) B/A is 85 to 300 and/or C/A is 45 to 200.

Here, the above-mentioned chlorogenic acid and caffeine are components contained in coffee beans and are contained in coffee beverages. It is generally known that as the roasting degree of coffee beans progresses, chlorogenic acid decomposes, while caffeine remains in the coffee beans without being decomposed. Therefore, as the roasting degree of coffee beans increases, that is, as the L value of the roasted coffee beans decreases, the caffeine concentration/chlorogenic acid concentration contained in the coffee beans increases.
In addition, both guaiacol and 4-ethylguaiacol are known as aroma components that characterize coffee beverages, and are generally contained in coffee beverages.
According to the study of the present inventor, it was found that adding guaiacol or 4-ethylguaiacol to various coffee extracts (base liquids) obtained using coffee beans sometimes reduces the unpleasant taste of the coffee beverage, and sometimes increases the unpleasant taste. Therefore, the present inventor made a hypothesis that controlling the concentrations of guaiacol and 4-ethylguaiacol in a certain coffee extract (base liquid) is effective in controlling the richness and unpleasant taste of the coffee beverage, and carried out a study. As a result, it was found that by simultaneously controlling the ratio of the caffeine concentration to the chlorogenic acid concentration and the guaiacol concentration, or the ratio of the caffeine concentration to the chlorogenic acid concentration and the 4-ethylguaiacol concentration, it is possible to effectively achieve both an improvement in richness and a reduction in unpleasant taste, and thus the coffee beverage of this embodiment was completed.

[Caffeine concentration/chlorogenic acid concentration]
In the coffee beverage of this embodiment, (i) A is 4.0 or more. A is preferably 4.2 or more, and more preferably 4.5 or more. This allows for both improved fullness and reduced unpleasant flavors, while also providing a good coffee feel and satisfying drinking experience. On the other hand, the upper limit of A is not particularly limited, but from the viewpoint of maintaining a coffee-like flavor, it is, for example, preferably 12 or less, more preferably 10 or less, and even more preferably 9 or less.
Incidentally, A tends to increase as the degree of roasting of coffee beans increases (the L value decreases); however, in the coffee beverage of this embodiment, the above condition (i) can be satisfied by further adding a caffeine component to a coffee extract obtained by a conventional method using a caffeine preparation or the like.

Furthermore, in the coffee beverage of this embodiment, the caffeine concentration is preferably 10 to 200 mg/100 ml, more preferably 20 to 150 mg/100 ml, even more preferably 40 to 100 mg/100 ml, and particularly preferably 50 to 80 mg/100 ml.
By setting the caffeine concentration to be equal to or higher than the lower limit, it becomes easier to improve the richness of the flavor, whereas by setting the caffeine concentration to be equal to or lower than the upper limit, it becomes possible to maintain a good balance between the improvement of the richness of the flavor and the reduction of unpleasant flavors.

[Guaiacol]
Guaiacol, also known as 2-methoxyphenol, is used in the artificial synthesis of vanillin and the like, and is also known as an aroma component resembling deep-roasted coffee.
In the coffee beverage of this embodiment, (ii) B/A is 85 to 300, preferably 90 or more, and more preferably 100 or more. This makes it possible to improve full-bodiedness while reducing unpleasant flavors. It also makes it possible to achieve a good balance between coffee flavor and drinkability. Meanwhile, B/A is preferably 280 or less, and from the viewpoint of obtaining a fuller body, more preferably 250 or less.
Furthermore, the concentration B of guaiacol in the coffee beverage of this embodiment is preferably 100 to 2500 ppb, and more preferably 200 to 2000 ppb.

[4-Ethylguaiacol]
4-Ethylguaiacol, also known as 2-methoxy-4-ethylphenol, is an aroma component known to have a deep-roasted coffee-like aroma.
In the coffee beverage of this embodiment, the C/A is 45 to 200, preferably 50 or more, and more preferably 70 or more. This makes it possible to improve the richness while reducing unpleasant flavors. It also makes it possible to achieve a good balance between the coffee flavor and the satisfying taste. On the other hand, the C/A is preferably 160 or less.
The concentration C of 4-ethylguaiacol in the coffee beverage of this embodiment is preferably 50 to 2000 ppb, more preferably 80 to 1500 ppb, and even more preferably 100 to 1200 ppb.

In this embodiment, the above A, B/A, and C/A are adjusted by, for example, separately adding caffeine, guaiacol, and 4-ethylguaiacol to a coffee extract obtained by a known method for adjusting the roasting degree of coffee beans.

[Coffee drinks]
The coffee beverage of this embodiment is a beverage made from components extracted or dissolved from coffee beans (coffee components) and beverages to which other components have been added, and is a beverage that gives off a coffee flavor when drunk. As described in the "Fair Competition Code for Labeling of Coffee-Containing Beverages, etc." established in 1977, it includes beverages made from coffee beans and beverages to which sugars, dairy products, emulsified edible oils and fats, and other edible materials have been added and sealed in a container. In this embodiment, even if the amount of coffee beans used is less than 1% by weight in terms of raw beans, the beverage is treated as a coffee beverage if it gives off a coffee flavor when drunk.

The above-mentioned coffee beans are not particularly limited, and examples of cultivated species include Arabica, Robusta, and Liberica. The varieties of coffee beans are not particularly limited, and examples of coffee beans include Mocha, Brazil, Colombia, Guatemala, Blue Mountain, Kona, Mandheling, and Kilimanjaro. The coffee beans may be one type or a blend of two or more types.
The conditions of roasting temperature and roasting environment of the coffee beans are not particularly limited, and a usual method can be used. In addition, the extraction method using roasted coffee beans is not particularly limited, and examples thereof include a drip type, a siphon type, a boiling type, a jet type, and a continuous type.

Here, the method of adding coffee to the coffee beverage of this embodiment is not particularly limited and can be determined appropriately by a person skilled in the art. For example, a solution (coffee extract) obtained by extracting ground roasted coffee beans with water or hot water, a coffee extract obtained by concentrating a coffee extract, instant coffee obtained by drying a coffee extract, etc., can be used, and one or more of these can be added to the beverage.
The ground roasted coffee beans include, but are not limited to, coarsely ground, medium ground, fine ground, and the like.
Meanwhile, according to the "Fair Competition Code for the Labeling of Drinking Milk," any drink containing 3.0% or more milk solids by weight is treated as a milk drink as of 2017. However, since the coffee drink according to this embodiment is a drink made from coffee beans, it will be treated as a coffee drink even if it contains 3.0% or more milk solids by weight.

In order to obtain a coffee-like flavor and deliciousness, the lower limit of the coffee soluble solids content in a coffee beverage is preferably 0.5% by mass or more, more preferably 0.9% by mass or more, and even more preferably 1% by mass or more.
On the other hand, the upper limit of the content of coffee soluble solids in a coffee beverage is preferably 2.5 mass% or less, more preferably 2.3 mass% or less, and even more preferably 2.0 mass% or less, from the viewpoint of maintaining a good coffee flavor.

The coffee beverage may be a black coffee beverage (with or without sweetener) that does not contain milk, or, if desired, a milk-based coffee beverage that contains one or more types of milk.

[Other ingredients]
Furthermore, the coffee beverage of the present embodiment may contain aroma components other than those described above, milk, sweeteners, acidulants, emulsifiers, pH adjusters (sodium bicarbonate, potassium carbonate, etc.), fruit juice, various nutritional components, colorants, diluents, antioxidants, thickening stabilizers, and the like, as long as the effects of the present invention are obtained.

Examples of the milk include raw milk, whole milk powder, skim milk powder, fresh cream, concentrated milk, partially skim milk, condensed milk, milk powder, and fermented milk. These may be used alone or in combination of two or more.
In the case of a milk-containing coffee beverage, the milk content is not particularly limited, but from the viewpoint of obtaining a good milk flavor and a good richness, the amount of milk solids (meaning the combined amount of milk fat and non-fat milk solids) is preferably 0.5 to 3.5 mass%, more preferably 0.8 to 2.5 mass%, and even more preferably 1.0 to 2.0 mass%.

The above sweeteners include low-intensity sweeteners such as sugars consisting of monosaccharides and disaccharides, oligosaccharides (combinations of about 2 to 10 monosaccharides), fructose glucose liquid sugar, high fructose liquid sugar, honey, sugar alcohols, xylitol, and D-sorbitol, and high-intensity sweeteners such as thaumatin, stevia extract, disodium glycyrrhizinate, acesulfame potassium, sucralose, aspartame, saccharin, neotame, and saccharin sodium. These may be used alone or in combination of two or more.

In particular, the coffee beverage of this embodiment preferably has a sugar content of 2.0 g/100 ml or less, more preferably 1.5 g/100 ml or less, and even more preferably 1.3 g/100 ml or less, which can more significantly improve the richness and reduce unpleasant flavors.
It is generally known that the inclusion of sugars in a coffee beverage tends to improve the body and mask unpleasant flavors. In contrast, the coffee beverage of the present embodiment satisfies the conditions (i) and (ii) above, and therefore can achieve both improved body and reduced unpleasant flavors even with a sugar content of 2.0 g/100 ml or less.
Examples of the sugars include monosaccharides such as glucose, galactose, and fructose, and disaccharides such as sucrose (including sugar and granulated sugar), lactose, maltose, and starch syrup (including glucose and maltose).

[container]
Examples of containers used for the coffee beverage of this embodiment include sealed containers made of glass, paper, plastic (polyethylene terephthalate, etc.), aluminum, steel, etc., or composite or laminated materials thereof. The type of container is not particularly limited, but examples include PET bottles, aluminum cans, steel cans, paper cartons, chilled cups, bottles, etc. From the viewpoint of maintaining the flavor of the coffee beverage, steel cans are preferred, and from the viewpoints of being lightweight and resealable, PET bottles, steel cans, and aluminum cans with lids are preferred.
The volume of the coffee beverage is not particularly limited, but is preferably 100 to 2000 g, and more preferably 100 to 500 g from the viewpoint of ease of drinking.

There are no particular limitations on the method of heat sterilization of bottled coffee beverages, but in Japan, heat sterilization is carried out in accordance with the provisions of the Food Sanitation Act. Specifically, there is a method in which the beverage is sterilized at high temperature for a short time, and then filled into a storage container that has been sterilized under aseptic conditions (UHT sterilization method), and a retort sterilization method in which the prepared liquid is filled into a storage container such as a can and then retorted.

The above describes embodiments of the present invention, but these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited to these.

<Method of analyzing aroma components>
10 mL of each coffee beverage to be analyzed was placed in a solid-phase microextraction (SPME) vial containing 3 g of NaCl, which was then sealed. Each vial was shaken at 40° C. for 5 minutes, and then a SPME fiber (DVB/CAR/PDMS, Stableflex 23Ga (Gray) 50/30 μm: SIGMA-ALDRICH) was exposed to the headspace in the vial.
The volatile components were adsorbed on the fiber for 30 minutes at 40° C., then desorbed at the injection port for 3 minutes, and analyzed by GC/MS. A calibration curve was prepared by the standard addition method, and cyclohexanol was used as the internal standard.
[GC/MS analysis conditions]
GC: Agilent Technologies 7890A.
MS: 5975C manufactured by Agilent Technologies.
Column: Agilent Technologies DB-WAX UI 30 m×0.25 mm, film thickness 0.25 μm.
Constant pressure mode: 122 KPa. Injection method: splitless. Carrier gas: He.
Inlet temperature: 240° C. Transfer line: 240° C.
Oven temperature: 40°C (5 min) → 5°C/min → 240°C (0 min).
MS conditions: scan mode
Quantitative ion: guaiacol m/z 81,
4-Ethylguaiacol m/z 152,
Cyclohexanol (internal standard) m/z 82

<Analysis conditions for caffeine and chlorogenic acid>
Each coffee beverage was filtered at 1000 rpm for 30 minutes using an ultrafiltration filter unit (Amicon Ultra) to obtain a sample. The caffeine content (mg/100 ml) and chlorogenic acid content (mg/100 ml) in 100 ml of the sample were then measured using UHPLC (Nexera (Shimadzu Corporation), detector: PDA) under the following conditions.
Column: ZORBAX EclipsePlus C18 (Agilent Technologies, Inc.)
Column oven temperature: 45°C
Mobile phase: ultrapure water containing 0.2% phosphoric acid and 8% methanol
Pump flow rate: 1.0 ml/min
Injection volume: 3 μl
Cell temperature control: 40°C
From each peak area, the caffeine content and chlorogenic acid content were calculated based on the area values of standard substances (caffeine: CAS 58-08-2, Wako Pure Chemical Industries, chlorogenic acid: CAS 327-97-9, SIGMA-ALDRICH).

[Test 1: Examination of body and off-flavor when varying B and C]
<Examples 1 to 13 and Comparative Examples 1 to 13>
(1) Preparation of control product Coffee beans (a mixture of Brazilian and Vietnamese coffee beans) were roasted to prepare three types of roasted coffee beans with different roast degrees (L value: 17.4, 20.1, 23.1). For each type of roasted coffee beans, Brazilian coffee beans and Vietnamese coffee beans with each L value were mixed in the weight ratios shown below.
Roasted coffee bean L value: 23.1 (Brazilian L value 24: Vietnamese L value 21 = 7:3)
L value: 20.1 (Brazilian L value 21: Vietnamese L value 18 = 7:3)
L value: 17.4 (Brazilian L value 18: Vietnamese L value 16 = 7:3)
55 g of each of the roasted coffee beans was extracted with 440 g of hot water at 95° C. to obtain each coffee extract.
Next, each coffee extract was mixed with sugar, milk (milk solids content 12.2% by mass), emulsifier, sodium caseinate, sodium bicarbonate, acesulfame potassium, and sucralose, sealed and filled into cans, and then retort sterilized to produce each coffee beverage (control products 1 to 5; sugar 0.5 g/100 ml) with the component concentrations shown in Table 1. In addition, caffeine preparations were added to control products 3 and 5 to achieve the concentrations shown in Table 1.

(2) Guaiacol or 4-ethylguaiacol was added to each control product at the concentrations shown in Tables 2 to 6 to prepare each coffee beverage.

(3) Sensory Evaluation The following sensory evaluations were carried out using the resulting coffee beverages. The results are shown in Tables 2 to 6.
Sensory evaluation: Each coffee beverage (20°C) was tasted by a panel of five or more coffee experts, who rated each of the following categories on a seven-point scale (1 to 7 points) for "off-flavor,""coffeeflavor,""drinkability," and "body-like flavor" according to the following evaluation criteria, and the average score was calculated. In addition, the standard value for each control product was set at 4 points.

Evaluation criteria: 7 points: Very strong compared to the control product; 6 points: Strong compared to the control product; 5 points: Slightly stronger compared to the control product; 4 points: Equivalent to the control product; 3 points: Slightly weaker compared to the control product; 2 points: Weaker compared to the control product; 1 point: Very weaker compared to the control product

[Test 2: Examination of body and off-flavor when sugar concentration is changed]
<Reference examples 1 to 3>
A coffee extract was similarly obtained using the roasted coffee beans (L value: 17.4) used in Test 1. The resulting mixture was then mixed with sugar, milk, an emulsifier, sodium caseinate, sodium bicarbonate, acesulfame potassium, and sucralose to give the component concentrations shown in Table 7, sealed in cans, and subjected to retort sterilization to produce each coffee beverage.
Next, a sensory evaluation was carried out in the same manner as in Test 1. The results are shown in Table 7.

From Table 7, it was found that compared to 0.5g/100ml of sugar, increasing the sugar content to 1.25g/100ml, 2.5g/100ml, or 4.5g/100ml tends to reduce unpleasant flavors and increase richness. In other words, by lowering the sugar content, it becomes more difficult to reduce unpleasant flavors and improve richness. From Tables 2 to 6, it was confirmed that in the coffee beverages of the examples, even with a sugar content of 0.5g/100ml, the effect of reducing unpleasant flavors and improving richness was sufficiently achieved.

Claims (10)

When the ratio of the caffeine concentration to the chlorogenic acid concentration (caffeine concentration/chlorogenic acid concentration) is A, the concentration of guaiacol is B (ppb), and the concentration of 4-ethylguaiacol is C (ppb),
(i) A is 4.5 or more;
(ii) A coffee beverage having a B/A of 85 to 300 and/or a C/A of 45 to 200. The coffee beverage according to claim 1, wherein the concentration of the guaiacol is 100 to 2500 ppb. The coffee beverage according to claim 1 or 2, wherein the concentration of 4-ethylguaiacol is 50 to 2000 ppb. A coffee beverage according to any one of claims 1 to 3, in which the sugar content is 2.0 g/100 ml or less. A coffee beverage according to any one of claims 1 to 4, containing milk. A coffee beverage according to any one of claims 1 to 5, packaged in a container. 1. A method for producing a coffee beverage, comprising the steps of:
When the ratio of the caffeine concentration to the chlorogenic acid concentration (caffeine concentration/chlorogenic acid concentration) is A, the concentration of guaiacol is B (ppb), and the concentration of 4-ethylguaiacol is C (ppb),
(i) A is 4.5 or more;
(ii) adjusting the B/A to 85 to 300 and/or the C/A to 45 to 200. The method further comprises the step of obtaining a coffee extract from the coffee beans,
8. The method for producing a coffee beverage according to claim 7, wherein in the preparation step, one or more selected from the group consisting of caffeine, guaiacol and 4-ethylguaiacol are added to the coffee extract. A method for reducing unpleasant flavors in a coffee beverage, comprising:
When the ratio of the caffeine concentration to the chlorogenic acid concentration (caffeine concentration/chlorogenic acid concentration) is A, the concentration of guaiacol is B (ppb), and the concentration of 4-ethylguaiacol is C (ppb),
(i) A is 4.5 or more;
(ii) A method for reducing unpleasant flavors in a coffee beverage, comprising the step of adjusting the B/A to 85 to 300 and/or the C/A to 45 to 200. The method further comprises the step of obtaining a coffee extract from the coffee beans,
10. The method for reducing unpleasant flavors in a coffee beverage according to claim 9, wherein in the preparation step, one or more selected from the group consisting of caffeine, guaiacol and 4-ethylguaiacol are added to the coffee extract.