JP7465245B2 - Method for producing beverage with full-bodied taste - Google Patents

Description

The present invention relates to a method for producing a beverage with rich flavor.

Factors that determine the deliciousness of food and drink include taste, aroma, texture, and color, but in recent years, "kokumi" has also come to be considered important as a factor that determines deliciousness. "Kokumi" is considered to be a taste that can be recognized when a balanced number of stimuli are given in the three senses of taste (gustation), aroma (smell), and texture (touch), and when one feels a richness, complexity, mouthfulness, and lastingness (Non-Patent Documents 1 and 2).
As substances that impart full-bodied flavor to foods and beverages, sulfur-containing compounds such as garlic-derived alliin, γ-glutamyl-S-allyl-L-cysteine (GSAC), S-methyl-L-cysteine sulfoxide (SMCS), onion-derived isoalliin (PeCSO), and γ-glutamyl peptide of isoalliin (PeCSO), as well as yeast-derived peptides, glycopeptides, Maillard peptides, and other peptides have been reported to impart thickness, complexity, persistence, and breadth to umami solutions (Non-Patent Documents 3, 4, 5). It has also been reported that adding heated onion concentrate to consommé soup imparts full-bodied flavor, particularly enhancing the persistence of the aroma (Non-Patent Document 6).

Such substances that impart full-bodied taste have the effect of enhancing the richness, duration, and breadth of the base taste, but beverages have a problem in that they are difficult to enhance because of their poor base taste (particularly umami) and texture, and a method that can impart full-bodied taste to beverages or effectively enhance it is desired. Examples of techniques that can impart full-bodied taste to beverages include a method of adding potato-derived dextrin with a DE of 2 to 5 to a coffee-containing beverage or tea beverage with a sugar content reduced to 2.5 w/v% or less (Patent Document 1), a method of enhancing the full-bodied taste of a beverage by adding cyclodextrin (Patent Document 2), a method of imparting full-bodied taste by adding a rare sugar containing D-psicose to food and beverages such as blended tea, black tea, and coffee and heating the mixture (Patent Document 3), and a method of imparting or enhancing full-bodied taste by adding an amino acid-containing composition containing specific amino acids (L-methionine, L-lysine, L-leucine, and L-threonine) in specific ratios to milk and other protein beverages (Patent Document 4).

JP 2012-115247 A Japanese Patent Application Laid-Open No. 54-145268 JP 2014-113059 A JP 2009-11209 A

Toshihide Nishimura, Clinical Nutrition, 119(6), 616-617 (2011) Toshihide Nishimura, Ai Egusuka, Monthly Food Chemical, 2014-8 Vol. 352: 25-31, (2014) Agricultural and Biological Chemistry 54(1), 163-169, 1990 Bioscience, Biotechnology, and Biochemistry, 58(1), 108-110, 1994 Food Chemistry 99, 600-604, 2006 Tsutomu Odawara et al., Abstracts of the 65th Annual Meeting of the Japanese Society of Nutrition and Food Science, p. 213 (2011)

As mentioned above, there are several known technologies for imparting full-bodied flavor to beverages; however, the types and flavors of beverages have become increasingly diverse in recent years, and existing technologies alone may not be able to impart full-bodied flavor to all beverages. It would be desirable to develop new methods that differ from existing technologies in order to broaden, even just a little, the types of beverages to which full-bodied flavor can be imparted.

The objective of the present invention is to provide a new method for effectively producing beverages with rich flavor without requiring complicated processes or special equipment.

As a result of intensive research into the above-mentioned problems, the present inventors discovered that a heated product of L-ergothioneine (heated L-ergothioneine) can effectively impart full body flavor to a beverage, and thus completed the present invention. The present invention includes, but is not limited to, the following aspects.
[1] The following steps a) to d):
a) preparing a beverage preparation;
b) adding 0.3 to 440 ppm (w/w) of L-ergothioneine to the beverage preparation;
Step c) adjusting the pH (at 20° C.) of the beverage preparation to between 5.0 and 7.5; and Step d) heating the beverage preparation containing L-ergothioneine.
The heating conditions in the step d) are such that, when the heating temperature (° C.) is X and the heating time (minutes) is Y, the heating conditions satisfy the following formula (1):
Formula (1) Y≧34×(X−60) ^−1.1 (where 61≦X≦150)
A method for producing a beverage, which satisfies the above.
[2] The following steps a) and x) to z):
a) preparing a beverage preparation;
Step x of preparing an L-ergothioneine-containing solution;
a step y) of heating the L-ergothioneine-containing solution to prepare a heated L-ergothioneine solution; and a step z) of mixing the heated L-ergothioneine solution with the beverage preparation so that the L-ergothioneine concentration in the solution is 0.3 to 440 ppm (w/w).
The heating conditions in the step y) are such that, when the heating temperature (° C.) (minutes) is X and the heating time (minutes) is Y, the heating conditions satisfy the following formula (1):
Formula (1) Y≧34×(X−60) ^−1.1 (where 61≦X≦150)
and the pH (20°C) is 5.0 to 7.5.
[3] The method for producing a beverage according to [1] or [2], wherein the beverage contains 10 to 20,000 ppb of pyrazines.

According to the present invention, beverages with a rich flavor can be effectively produced simply by adding heated L-ergothioneine. This production method has the advantage that it does not require investment in special equipment and has very little negative impact on industrial productivity.

1 is a graph plotting the results of Experiment 6 of the embodiment.

Hereinafter, embodiments of the present invention will be described, however, the embodiments of the present invention are not limited to the following examples.
The present invention is based on the discovery that by incorporating heated L-ergothioneine as an active ingredient, it is possible to impart full-bodied taste to a beverage. Here, in the present invention, "full-bodied taste" means a feeling of overall mass, a rich taste with thickness and depth, and a fullness of taste in a sensory test of a beverage, and in the present invention, "imparting full-bodied taste" means enhancing or emphasizing "full-bodied taste". Specifically, this refers to enhancing the richness, duration, and breadth of the base taste of the beverage (tea, coffee, etc.), and in the case of a tasteless beverage (water, carbonated water, etc.), enhancing the richness that is recognized as a satisfying taste.

(L-Ergothioneine)
The present invention is based on the discovery that a full-bodied taste can be imparted to a beverage by including heated L-ergothioneine (L-(+)-Ergothioneine (CAS 58511-63-0)) (hereinafter, L-ergothioneine will be abbreviated as EGT) as an active ingredient. The addition of unheated EGT to a beverage does not produce the full-bodied taste imparting effect of the present invention, but the addition of heated EGT produces the full-bodied taste imparting effect, and compared to the absence of EGT, an effect of enhancing or accentuating the full-bodied taste of the beverage can be obtained. EGT is a compound represented by the following formula I, which is known to have excellent thermal stability, and it is believed that a part of the structure of this compound changes upon heat treatment, thereby exerting the effect of the present invention.

Heated EGT refers to an EGT solution obtained by heating EGT in a solution state at 61-150°C for a time period that satisfies the conditions of formula (1) described below. Here, the EGT that is the raw material for the heated EGT may be a commercially available EGT obtained by chemical synthesis, or an extract or refined product thereof from mushrooms or sake lees that contain EGT. Mushrooms that can be used for the extraction of EGT include the Golden/Yellow Oyster mushroom (Pleurotus cornucopiae var. citrinopileatus), which is a mushroom of the Pleurotus genus in the Pleurotus family; Agaricus bisporus, such as the White Button Mushroom, Crimini Mushroom, and Portabella Mushroom; Grey Oyster Mushroom (Pleurotus ostreatus); Shiitake mushroom (Lentinula edodes); Maitake mushroom (Grifola Frondosa); Ganoderma lucidum; Yamabushitake mushroom (Hericium erinaceus); Yanagimatsutake mushroom (Agrocybe aegerita); Chanterelle mushroom (Cantharellus Examples of such mushrooms include Boletus cibarius, Boletus edulis, and Morchella esculenta, and these can be used alone or in combination. Of these, Tamogitake mushroom is preferred due to its high EGT content. When using an extract as EGT, it is preferable to carry out a deodorization process or the like to produce a crude product, since the flavor of components other than EGT may affect the beverage.

(Beverages)
The beverage obtained by the present invention preferably has a pH (20°C) of 5.0 to 7.5. The pH (20°C) is more preferably 5.5 to 7.0, and even more preferably 5.5 to 6.5. In beverages with a pH of less than 5.0, where sourness is perceived, there are various methods for controlling the full-bodied taste, such as the type and amount of acid, and the type and amount of sweetener used in combination, so that the problem of the present invention is difficult to recognize, and the effect of imparting full-bodied taste by adding heated EGT of the present invention may be difficult to perceive. On the other hand, when the pH of the beverage exceeds 7.5, the dissolved carbon dioxide in the beverage may become carbonate ions (CO ₃ ²⁻ ), making it difficult to control the stimulus balance of taste, aroma, etc., and it may be difficult to impart the desired delicious full-bodied taste. The pH of the beverage can be easily measured using a commercially available pH meter.

Among aroma substances, pyrazines have been reported to be substances that impart fullness to the flavor of food and beverages, thereby imparting richness (Saito Tomoaki, Food Richness and Richness, Taste and Smell Journal, 11, 165-174 (2004)). When the base beverage contains pyrazines, the effect of imparting fullness by adding heated EGT according to the present invention is additively or synergistically expressed, and thus beverages containing pyrazines are an example of a preferred embodiment of the beverage of the present invention.

Specifically, the beverage obtained by the present invention preferably contains 10 to 20,000 ppb of pyrazines. An example of a beverage containing pyrazines is a beverage containing an extract of a roasted plant (roasted plant). Examples of plants that can be used as raw materials for roasted plants include tea leaves belonging to Camellia sinensis, such as green tea, black tea, oolong tea, and pu-erh tea; grains belonging to the Poaceae family, legumes, and Polygonaceae families, such as Job's tears, brown rice, barley, and buckwheat; and coffee beans belonging to the Rubiaceae family, Coffea genus. In this specification, a beverage containing tea leaf extract as a main component is referred to as a tea beverage, a beverage not containing a plant belonging to Camellia sinensis and containing an extract of grains as a main component is referred to as a grain tea beverage, and a beverage containing an extract of coffee beans is referred to as a coffee beverage. Among these, because the effects of the present invention are particularly pronounced, the beverage of the present invention is preferably a grain tea beverage such as barley tea or brown rice tea, or a tea beverage such as green tea. The beverage of the present invention may contain one type of roasted plant extract, or may contain multiple types of roasted plant extract. For example, a blended tea is also a suitable embodiment of the present invention.

As mentioned above, the beverage preferably contains 10 to 20,000 ppb of pyrazines. If the beverage is a coffee beverage, it preferably contains 2,000 to 20,000 ppb of pyrazines, more preferably 3,000 to 17,000 ppb, and even more preferably 4,000 to 15,000 ppb. If the beverage is a cereal tea beverage, it preferably contains 1,000 to 10,000 ppb, more preferably 2,000 to 9,000 ppb, and even more preferably 3,000 to 8,000 ppb. If the beverage is a tea beverage, it preferably contains 10 to 500 ppb, more preferably 12 to 400 ppb, and even more preferably 15 to 300 ppb. In the present invention, pyrazines refer to the total amount of pyrazine, 2-methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, ethylpyrazine, 2,3-dimethylpyrazine, 3-ethyl-2,5-dimethylpyrazine, and 2-ethyl-3,5-dimethylpyrazine.

The concentration of pyrazines in beverages can be determined by GC/MS. The quantification ions can be selected from the following ions with good detection sensitivity, peak shape, and peak separation. If the peak shape or sensitivity is not good with any of the following ions, the sample liquid can be diluted to an appropriate ratio with distilled water or SIM mode can be used.
Pyrazine m/z 80 or 53
2-Methylpyrazine m/z 94, 67 or 53
2,5-dimethylpyrazine m/z 108, 81 or 109
2,6-dimethylpyrazine m/z 108, 67, 81 or 109
2,3-Dimethylpyrazine m/z 67, 108, 66 or 109
Ethylpyrazine m / z 107, 108, 80, 53 or 81
3-Ethyl-2,5-dimethylpyrazine m/z 135, 136, 108, 107 or 121
2-Ethyl-3,5-dimethylpyrazine m/z 135, 136, 108 or 121
Generally, when a food or drink has "thickness", it is perceived as having a rich flavor and "body taste". Therefore, when a beverage has a thickness, the problem of the present invention is difficult to manifest. On the other hand, it is generally difficult for consumers to perceive "body taste" in a beverage without a thickness. Since the present invention can impart "body taste" to a beverage without a thickness, it can be said that a beverage without a thickness is preferable as a target for applying the manufacturing method of the present invention. Specifically, a beverage without a thickness refers to a beverage having a viscosity of 20 mPa·s or less, preferably 15 mPa·s or less, more preferably 10 mPa·s or less, or a beverage that does not contain a thickener. In this specification, the viscosity refers to a value measured using a B-type rotational viscometer under the following conditions: rotation speed: 60 rpm, sample temperature: 10°C, and measurement time: 30 seconds.

It is also known empirically that foods and beverages containing fats and oils have a rich taste. On the other hand, it is generally difficult for consumers to perceive a rich taste in beverages that do not contain fats and oils. Since the present invention can impart a rich taste to beverages that do not contain fats and oils, beverages that do not contain fats and oils are preferable targets for applying the manufacturing method of the present invention. A beverage that does not contain fats and oils is a beverage that does not contain animal fats such as milk fat or vegetable fats such as palm oil (including processed vegetable fats and oils), and specifically, a beverage that has a lipid content of 1.5 w/v% or less, preferably 1.0 w/v% or less, more preferably 0.5 w/v% or less, and particularly preferably 0 w/v%.

Similarly, beverages with low umami components are generally difficult to make consumers perceive a "rich taste," but the manufacturing method of the present invention can impart a "rich taste," making them a preferable target of the present invention. Examples of beverages with low umami components include beverages with low sugar or dextrin content and beverages with low protein content. A beverage with low sugar content refers to a beverage with a total carbohydrate content of 6.0 w/v% or less, preferably 5.0 w/v% or less, more preferably 4.0 w/v% or less, even more preferably 3.0 w/v% or less, particularly preferably 2.0 w/v% or less, or 0 w/v%. A beverage with low protein content refers to a beverage with a protein content of 1.5 w/v% or less, preferably 1.0 w/v% or less, more preferably 0.5 w/v% or less, particularly preferably 0 w/v%.

Similarly, beverages with low soluble solids are generally difficult to make consumers perceive a rich taste, but the manufacturing method of the present invention can impart a rich taste to beverages, making them preferable targets of the present invention. A beverage with low soluble solids is one in which the soluble solids content (Brix value) in the beverage is 8 or less, preferably 6 or less, more preferably 4 or less, even more preferably 2 or less, and particularly preferably 1 or less. There is no particular lower limit for the soluble solids content, but it is preferable for the soluble solids content (Brix value) in the beverage to be 0.1 or more, since it can more effectively impart rich taste. The soluble solids content can be evaluated by the Brix value obtained using a saccharometer or refractometer. Here, the Brix value is the refractive index measured at 20°C converted into the mass/mass percentage of the sucrose solution based on the conversion table of the ICUMSA (International Commission on Uniform Methods of Sugar Analysis). The unit is expressed in "°Bx", "%" or "degree".

In addition, the beverage of the present invention may contain various additives, as in the case of ordinary beverages, to the extent that the effects of the present invention are not impaired. Examples of various additives include flavorings, extracts, vitamins, minerals, colorants, antioxidants, etc.

The beverage of the present invention also includes a concentrated liquid that is diluted with water or the like for drinking.
(Method of producing beverages)
In the present invention, EGT may be blended into a beverage preparation and then heat-treated so that heated EGT is contained in the beverage (Method A), or heated EGT may be blended into the beverage (Method B). That is, the present invention encompasses an embodiment of a production method having the following steps:

(Method A)
A method for producing a beverage comprising the following steps a) to d):
a) preparing a beverage preparation;
b) adding EGT to the beverage preparation;
Step c) adjusting the pH of the beverage preparation to between 5.0 and 7.5; and Step d) heating the beverage preparation containing EGT.
(Method B)
A method for producing a beverage comprising the steps a) and x) to z) of:
a) preparing a beverage preparation;
Step x of preparing an EGT-containing solution;
y) heating the EGT containing solution to prepare a heated EGT solution; and z) mixing the beverage preparation with the heated EGT solution.

Here, method A will be described in detail using an example in which the beverage is a green tea beverage. Step a) of preparing the beverage liquid includes (a1) a pasteurization step to obtain roasted plants (tea leaves), (a2) an extraction step to obtain a roasted plant extract (tea leaf extract) from the roasted plants, and (a3) a step of adding an antioxidant, water, etc., as necessary, to the tea leaf extract to prepare a blended liquid.

(a1) The roasting step can be carried out using a roasting machine or a roasting machine used in the tea processing process. It is preferable to adopt conditions for the roasting step that can produce pyrazines. For example, there is heat roasting at a tea temperature of 100 to 160°C for 5 to 30 minutes, or heat roasting at a tea temperature of 150 to 250°C for 5 to 20 minutes.

(a2) In the extraction step, a tea leaf extract is obtained from the roasted tea leaves. As the extraction method, known methods such as kneader extraction, stirring extraction, drip extraction, column extraction, etc. can be used. The extraction ratio (mass of water for extraction/mass of tea leaves) and extraction time can be set appropriately depending on the extraction method, but for example, the extraction ratio is preferably 5 to 50 times, more preferably 10 to 40 times, and particularly preferably 15 to 30 times. In addition, the extraction time is preferably 3 to 120 minutes, and particularly preferably 7 to 60 minutes.

As the water for extraction, for example, distilled water, desalted water, tap water, alkaline ionized water, deep sea water, ion-exchanged water, deoxygenated water, water containing inorganic salts, etc. can be appropriately selected and used. In particular, it is preferable to use pure water or ion-exchanged water. From the viewpoint of extraction efficiency and flavor, the temperature of the water for extraction is preferably 50 to 95°C, and more preferably 60 to 90°C. After cooling, the obtained tea leaf extract is filtered and/or centrifuged to separate impurities.

(a3) In the blending process, antioxidants (such as ascorbic acid) are added as necessary. In addition, the product may be diluted with water or the like so that the pyrazines in the final beverage are 10 to 20,000 ppb.

In step b), EGT is added to the beverage preparation to prepare an EGT-containing beverage preparation. EGT is added so that the EGT concentration in the preparation is 0.3 ppm (w/w) or more, preferably 0.5 ppm (w/w) or more, more preferably 1 ppm (w/w) or more, even more preferably 4 ppm (w/w) or more, and particularly preferably 6 ppm (w/w) or more. There is no particular upper limit to the EGT concentration, but since adding a large amount of EGT does not increase the effect of imparting full-bodied flavor, taking into account economic benefits, it is about 440 ppm (w/w) or less. It is preferably 300 ppm (w/w) or less, more preferably 200 ppm (w/w) or less, even more preferably 100 ppm (w/w) or less, and particularly preferably 80 ppm (w/w) or less.

In step c), the pH of the beverage preparation is adjusted to 5.0 to 7.5. The beverage preparation used in step c) may be the beverage preparation prepared in step a), the beverage preparation containing EGT in step b), or the beverage preparation obtained by heating the EGT-containing beverage preparation in step d) described below. The preparation step of step (a3) and step c) may be carried out simultaneously. The pH of the beverage preparation may be appropriately adjusted using a pH adjuster such as sodium bicarbonate or sodium hydroxide.

In step d), the beverage preparation containing EGT is heat-treated. Step d) may be performed at any time after the step of adding EGT in step b), and may be performed subsequent to step b), or step b) may be followed by step c) and then step d). In step d), the EGT-containing beverage preparation is subjected to a heat treatment based on the following formula (1):
Formula (1) Y≧34×(X−60) ^−1.1 (where 61≦X≦150)
Here, X is the heating temperature (°C) and Y is the heating time (min). In this specification, the temperature described in relation to the heat treatment means the liquid temperature. It has been found that when heating is performed under conditions that satisfy formula (1), it is possible to obtain heated EGT that can effectively impart "kokumi" (rich taste).

The heating temperature is not particularly limited as long as it is in the range of 61 to 150°C and satisfies the condition of formula (1), but is preferably 65°C or higher, more preferably 80°C or higher, and even more preferably 90°C or higher. At temperatures below 61°C, no thermal change in EGT can be expected, and the effect of imparting full-bodied flavor by the heated EGT of the present invention may not be obtained. In relation to the effects of the present invention, the upper limit of the heating temperature is 150°C, and preferably about 140°C or lower.

The heating time may be any time as long as it satisfies the condition of formula (1) depending on the heating temperature. The upper limit of the heating time is usually preferably 60 minutes or less, more preferably 30 minutes or less, and even more preferably 15 minutes or less.

The heated EGT-containing beverage preparation obtained by method A can be used as is or diluted to produce a packaged beverage. When producing a packaged beverage, step c) or step d) is followed by step e) of filling the beverage into a container. As with general beverages, containers into which the beverage can be filled include molded containers whose main component is polyethylene terephthalate (so-called PET bottles), metal cans, paper containers composited with metal foil or plastic film, and ordinary packaging containers such as bottles.

Next, method B will be described in detail using the example where the beverage is a green tea beverage. Like method A, step a) of preparing the beverage liquid includes (a1) a pasteurization step to obtain roasted plants (tea leaves), (a2) an extraction step to obtain a roasted plant extract (tea leaf extract) from the roasted plants, and (a3) a step of adding an antioxidant, water, etc. to the tea leaf extract as necessary to prepare a blended liquid.

In step x), an EGT-containing solution is prepared. The EGT in the solution is at least 1.0 ppm, preferably at least 3.0 ppm, more preferably at least 5 ppm, and even more preferably at least 10 ppm. If the EGT is in a dissolved state, there is no particular upper limit to the EGT concentration in the solution, but it is usually about 10,000 ppm. The solvent for the EGT solution is preferably water, and for example, distilled water, desalted water, tap water, alkaline ionized water, deep ocean water, ion-exchanged water, deoxygenated water, water containing inorganic salts, etc. can be appropriately selected and used. When using a liquid extract from mushrooms, sake lees, etc. as EGT, it can be used as is or after concentration, etc., as necessary.

In step y), the EGT-containing solution is heated to prepare a heated EGT solution. The heating conditions in step y) are the same as those in step d) of method A. Note that if the extract is concentrated by heating in step x) and the heating conditions satisfy the conditions of step y), step y) can be omitted.

In step z), the beverage preparation liquid prepared in step a) is mixed with the heated EGT solution obtained in step y). The mixture is mixed so that the EGT concentration in the mixture is 0.3 to 440 ppm (w/w). The EGT concentration in the mixture is preferably 0.5 ppm (w/w) or more, more preferably 1 ppm (w/w) or more, even more preferably 4 ppm (w/w) or more, and particularly preferably 6 ppm (w/w) or more. In addition, since the effect of imparting full-bodied flavor is not enhanced even if a large amount of EGT is added, the concentration is 440 ppm (w/w) or less, taking into consideration the economic merit, and is preferably 300 ppm (w/w) or less, more preferably 200 ppm (w/w) or less, even more preferably 100 ppm (w/w) or less, and particularly preferably 80 ppm (w/w) or less.

Adjust the pH of the mixture as necessary so that it is within the range of 5.0 to 7.5. The pH of the mixture can be adjusted appropriately using a pH adjuster such as sodium bicarbonate or sodium hydroxide.

The mixture obtained by method B of the present invention can be used as is or diluted to produce a packaged beverage.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. The components and physical properties in the examples were measured by the following methods.
(Viscosity Measurement)
The viscosity was measured using a Brookfield viscometer under the following conditions:
- Model used: B-type viscometer (TVB-10 model, manufactured by Toki Sangyo Co., Ltd.)
Rotor: No. 20
Measurement sample: 400 mL
Measurement temperature: 10°C
Measurement time: 30 seconds Rotor rotation speed: 60 rpm
(Measurement of soluble solids)
The Brix value at 20° C. was measured using a sugar refractometer (Atago Co., Ltd., RX-5000).

(Quantitative determination of pyrazines)
5 ml of the sample beverage was placed in a 20 ml screw-type glass bottle (diameter 18 mm, manufactured by Gestell), sealed with a metal cap with a polytetrafluoroethylene (PTFE) septum (manufactured by Gestell), and aroma components were extracted by solid phase microextraction (SPME). Quantitation was performed by the standard addition method using the peak area detected in the EIC mode of GC/MS. The equipment and conditions used are shown below.
・SPME fiber: StableFlex/SS, 50/30μm DVB/CAR/PDMS (manufactured by Sperco)
- Fully automated volatile component extraction and introduction device: MultiPurposeSampler MPS2 XL (Gestell)
Preheating: 40°C for 5 minutes Stirring: None Extraction of volatile components: 40°C for 30 minutes Desorption time of volatile components: 3 minutes GC oven: GC7890A (Agilent Technologies)
Column: VF-WAXms, 60m x 0.25mm id df = 0.50μm (Agilent Technologies)
GC temperature conditions: 40°C (5 min) → 5°C/min → 260°C (11 min)
Carrier gas: Helium, 1.2 ml/min, constant flow rate mode Injection: Splitless method Inlet temperature: 250°C
Mass spectrometer: GC/MS Triple Ouad7000 (Agilent Technologies)
-Ionization method: EI (70 eV)
Measurement method: Scan measurement, or simultaneous scan and SIM measurement Scan parameters: m/z 35 to 350
The pyrazine content is the total amount of pyrazine, 2-methylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, 2,3-dimethylpyrazine, ethylpyrazine, 3-ethyl-2,5-dimethylpyrazine, and 2-ethyl-3,5-dimethylpyrazine. The ions used for the determination were as follows:
・Pyrazine m/z 80
2-Methylpyrazine m/z 67
2,5-Dimethylpyrazine m/z 108
2,6-Dimethylpyrazine m/z 108
2,3-Dimethylpyrazine m/z 108
Ethylpyrazine m/z 107
3-Ethyl-2,5-dimethylpyrazine m/z 135
2-Ethyl-3,5-dimethylpyrazine m/z 135
(quantification of lipids, carbohydrates, and proteins)
The sample beverages were analyzed for lipid, carbohydrate, and protein content as defined by the Food Labeling Standards (enforced April 1, 2015) based on Article 4, Paragraph 1 of the Food Labeling Act (Act No. 70 of 2013).

(Experiment 1) Effect of Heated EGT on Providing Body Flavor (Green Tea Drink A)
First, a green tea beverage was produced using green tea leaves. The green tea leaves were subjected to a series of rough tea processing steps, including applying steam heat to the raw tea leaves to inactivate the oxidizing enzymes contained in the raw tea leaves (de-blueing), kneading by rough rolling, rolling, medium rolling and fine rolling, and drying, and then pasteurization (using a rotary drum type pasteurizer; 100°C, 10 minutes). 4000g of ion-exchanged water heated to 65°C and 130g of the above-mentioned green tea leaves were placed in a kneader and stirred for 5 minutes. The mixture was cooled to below 30°C, and the tea leaves were removed by centrifugation to obtain a green tea extract, which was then diluted with water so that the soluble solids (Brix value) derived from the green tea leaves was 0.3°Bx. To this green tea extract, 400 ppm of L-ascorbic acid and 20 ppm or 440 ppm (w/w) of ergothioneine (EGT) (manufactured by TETRAHEDRON, purity 99.5% or more) were added, and sodium bicarbonate was added to adjust the pH (20°C) to 6.4 to obtain a beverage. This beverage was heated at 135°C for 30 seconds using a heat exchanger, cooled to about 80°C, filled into a 350 mL heat-resistant PET bottle, sealed, and then cooled to 20°C to obtain a bottled beverage (pyrazine content: 17.4 ppb, protein: 0% w/v, lipid: 0% w/v, carbohydrate: 0% w/v, soluble solids: 0.3°Bx, viscosity: 2 mPa·s, pH 6.1). For comparison, a bottled beverage (20°C) was also produced by filling the beverage in a PET bottle without heat treatment. In addition, packaged beverages that were heat-treated and packaged beverages that were not heat-treated were produced in the same manner, except that EGT was not added.

A drinking test was conducted by five expert panelists on the resulting packaged beverages, and the full-bodied taste was evaluated by the sensory panel. A beverage without added EGT and that had not been heat-treated was used as a control for this sensory evaluation. The five expert panelists were presented with pairs of control and EGT-added beverages (one unheated and one heat-treated), and the panelists evaluated which of the pairs presented had the full-bodied taste by a two-point discrimination test. The results are shown in Table 1. It was found that the addition of EGT alone does not produce the full-bodied taste effect, but that the addition of EGT and heat treatment does produce the full-bodied taste effect.

(Experiment 2) Study of EGT concentration (1)
A green tea extract was obtained in the same manner as in Experiment 1, and EGT 0-440 ppm and L-ascorbic acid 350 ppm were added thereto, and sodium bicarbonate was added to adjust the pH to 6.4 to obtain a beverage. This beverage was hot-packed in 190 mL cans at 180 g each, and then heat-treated at 135°C for 1.5 minutes using a retort sterilizer. The beverage was then cooled to 20°C to obtain a packaged beverage (pyrazine content: 17.5 ppb, protein: 0% w/v, lipid: 0% w/v, carbohydrate: 0% w/v, soluble solids: 0.3°Bx, pH 6.1). A sensory evaluation was carried out on the obtained packaged beverage by five expert panelists. The sensory evaluation was carried out by individually evaluating the strength of the body of the heat-treated beverage based on the following evaluation criteria, using the unheated beverage at each EGT concentration as a control, and summarizing the evaluation results after discussion. The full-bodied taste was evaluated based on the intensity of the full-bodied taste of the sample containing 20 ppm EGT and heated, which was evaluated by all the panelists as having full-bodied taste in Experiment 1, and was given a score of 4.

[Kokumi evaluation criteria]
4: Stronger full-bodied taste compared to the control (unheated product) 3: Full-bodied taste compared to the control (unheated product) 2: Slight full-bodied taste compared to the control (unheated product) 1: No difference in full-bodied taste intensity compared to the control (unheated product) The results are shown in Table 2. Beverages containing 0.3 ppm or more of heated EGT had a slightly full-bodied taste compared to the control. Beverages containing 1.0 ppm or more had effectively imparted full-bodied taste.

(Experiment 3) Study of EGT concentration (2)
A similar experiment was conducted, except that the green tea leaves of the green tea beverage in Experiment 2 were replaced with roasted tea leaves. The roasted tea leaves were prepared by subjecting fresh tea leaves after plucking to crude tea processing (deamination of green tea leaves, rough rolling, rolling, medium rolling, fine rolling, drying) and then heat-processing at 180°C for 15 minutes in a rotary drum roaster. The resulting packaged beverage (pyrazine content: 147.7 ppb, protein: 0% w/v, lipid: 0% w/v, carbohydrate: 0% w/v, soluble solids: 0.3°Bx, viscosity: 2 mPa·s, pH 6.1) was evaluated for full-bodiedness in the same manner as in Experiment 2.

The results are shown in Table 3. Even in roasted tea beverages, beverages containing 0.3 ppm or more of heated EGT had a slightly richer flavor than the control. Moreover, beverages containing 1.0 ppm or more effectively imparted richness.

(Experiment 4) Study on EGT concentration (3)
A similar experiment was conducted by replacing the green tea beverage of Experiment 2 with a barley tea beverage. Six-row barley was roasted by hot air roasting until the L value reached 32. 30 g of the roasted barley grains were immersed in 1 L of water, boiled for 10 minutes, and then solid-liquid separated to obtain a barley tea extract, which was diluted with water so that the soluble solids (Brix value) derived from barley tea was 0.3° Bx. EGT 0-440 ppm and sodium bicarbonate were added to the extract to adjust the pH to 6.5 to obtain a beverage. This beverage was hot-packed in 180 g portions into 190 mL cans, and then heated at 135° C. for 1.5 minutes using a retort sterilizer. The resulting packaged beverage was cooled to 20° C. (pyrazine content: 5965.5 ppb, protein: 0% w/v, lipid: 0% w/v, carbohydrate: 0% w/v, soluble solids: 0.3° Bx, viscosity: 3 mPa·s, pH 6.3). The resulting packaged beverage was evaluated for full-bodied flavor in the same manner as in Experiment 2.

The results are shown in Table 4. In the barley tea beverages, beverages containing 0.3 ppm or more of heated EGT also had a slightly richer flavor than the control. Moreover, beverages containing 1.0 ppm or more effectively imparted richness.

(Experiment 5) Study of EGT concentration (4)
A similar experiment was carried out by replacing the green tea beverage of Experiment 2 with a coffee beverage. First, a black coffee beverage was produced. Coffee beans (Guatemala species) were roasted to medium roast (L value 20) using a coffee bean roaster. The roasted coffee beans were ground and extracted (95°C) using a drip extractor to obtain a coffee extract in an amount 10 times the amount (weight) of the coffee beans, and the coffee bean-derived soluble solids (Brix value) was diluted with water to 1.1°Bx. EGT 0-440 ppm and sodium bicarbonate were added to the extract to adjust the pH to 6.3 to obtain a beverage. The black coffee beverage was heated at 100°C for 3 minutes using a heat exchanger and filled into a PET bottle under aseptic conditions to obtain a bottled black coffee beverage (pyrazine content: 9330 ppb, protein: 0% w/v, lipid: 0% w/v, carbohydrate: 0% w/v, soluble solids: 0.3°Bx, viscosity: 3 mPa·s, pH 6.3).

Next, a milk-added coffee beverage was produced. Sucrose 5.0% w/v, skim milk powder 1.5% w/v, and fresh cream 2.0% w/v were added to the above coffee extract (diluted with water to a Brix value of 1.1°Bx), and EGT 0-440 ppm and sodium bicarbonate were added to adjust the pH to 7.0 to obtain a beverage. This milk-added coffee beverage was heated at 145°C for 20 seconds using a heat exchanger and filled into PET bottles under aseptic conditions to obtain a packaged milk-added coffee beverage (pyrazine content: 4675 ppb, protein: 0.8% w/v, lipid: 0.5% w/v, carbohydrate: 5.0% w/v, soluble solids: 7.0°Bx, viscosity: 5 mPa·s, pH 6.8). The resulting packaged beverage was evaluated for full-bodied flavor in the same manner as in Experiment 2.

The results are shown in Table 5. In the case of black coffee beverages, beverages containing 0.3 ppm or more of heated EGT were perceived as having a slightly richer taste than the control. Furthermore, beverages containing 1.0 ppm or more effectively imparted richness. In the case of coffee beverages with milk, beverages containing 0.5 ppm or more of heated EGT were perceived as having a slightly richer taste than the control, and beverages containing 1.0 ppm or more effectively imparted richness. Compared to coffee beverages with milk, black coffee beverages tended to have a more pronounced effect of imparting richness.

(Experiment 6) Investigation of Heating Conditions A green tea beverage containing 20 ppm of EGT was produced in the same manner as in Experiment 2. 50 mL of this beverage was placed in plastic containers with lids and heated in a water bath at 60 to 95° C. When the heating temperature was 110° C. or higher, the beverage was heated using a heat exchanger or a retort sterilizer to obtain a packaged beverage in a plastic bottle or can.

A panel of four experts conducted a drinking test on the resulting packaged beverages, and conducted a sensory evaluation of the full-bodied taste. The sensory evaluation was conducted using a beverage that had not been heat-treated as a control. The expert panel was presented with pairs of a control beverage and a heat-treated beverage, and the panel conducted a two-point discrimination test to determine which beverage of the pair they felt had the full-bodied taste.

Beverages that were judged to have a clearly stronger kokumi than the control, i.e., beverages that were rated as "strong" or "slightly stronger" by three or more of the four panelists, were rated as ◯, and beverages that were rated as "strong" by all four panelists were rated as ◎. On the other hand, beverages that were rated as "strong" or "slightly stronger" by less than three of the four panelists were rated as "x". The results are shown in Table 6. The results are also plotted in Figure 1. From the data for ◯ and ◎, the range in which the effect of heat treatment is effective can be expressed by the approximate formula Y≧34×(X-60) ^−1.1 , where X is the heating temperature (°C) and Y is the heating time (minutes).

(Experiment 7) Effect of Heated EGT on Providing Body Flavor (Water)
Bottled mineral water (Suntory Natural Mineral Water) was used (pH 7.0). 20 ppm (w/w) of EGT was added to this water to obtain a beverage. This beverage was heated at 135°C for 30 seconds using a heat exchanger, cooled to about 80°C, filled into a 350 mL heat-resistant PET bottle, sealed, and then cooled to 20°C to obtain a packaged beverage (pyrazine content: 0 ppb, protein: 0% w/v, lipid: 0% w/v, carbohydrate: 0% w/v, soluble solids: 0°Bx, pH 6.9). For comparison, a packaged beverage (20°C) was also produced in which the beverage was filled into a PET bottle without being heat-treated. In addition, packaged beverages that had been heat-treated and packaged beverages that had not been heat-treated were produced in the same manner except that no EGT was added. The obtained packaged beverage (EGT-containing water) was evaluated by a two-point discrimination test in the same manner as in Experiment 1.

The results are shown in Table 7. It was found that the effect of imparting full-bodied flavor was not apparent simply by adding EGT, but that the effect of imparting full-bodied flavor was apparent by adding EGT and then carrying out a heat treatment. However, the effect of imparting full-bodied flavor in water was smaller than that in the case of the green tea beverage in Experiment 1. In the case of the green tea beverage, the full-bodied flavor was clearly stronger than in the control, whereas in the case of water, the full-bodied flavor was only slightly stronger.

(Experiment 8) Effect of Heated EGT on Providing Body Flavor (Green Tea Drink B)
The bottled green tea beverage (without EGT addition, heat sterilization) produced in Experiment 1 was used as a beverage to impart full-bodied taste. On the other hand, EGT was added and dissolved in pure water to prepare an EGT solution containing 500 ppm (w/w), which was then hot-packed in 180 g portions into 190 mL cans, and then heated at 135°C for 1.5 minutes using a retort sterilizer, followed by cooling to 20°C to produce an EGT-heated solution. The bottled green tea beverage was opened and poured into a plastic cup, and the EGT-heated solution was mixed so that the EGT concentration in the green tea beverage was the concentration shown in Table 8, to produce an EGT-containing green tea beverage (pH 6.3). As a control, a green tea beverage was also produced by mixing the EGT-heated solution with the same amount of water (without EGT addition). The obtained green tea beverage was subjected to a drinking test by five expert panelists, and the full-bodied taste was evaluated by sensory evaluation. The sensory evaluation was carried out using a beverage without EGT as a control. A panel of five experts was presented with pairs of a control and an EGT-added beverage, and the panel evaluated which beverage in each pair had the more kokumi taste using a two-point discrimination test.

The results are shown in Table 8. It was confirmed that adding heated EGT solution imparts a full-bodied taste. The majority of the panelists rated the beverage to which heated EGT solution was added so that the EGT level was 0.5 ppm or higher as having a full-bodied taste, and all panelists rated the beverage to which heated EGT solution was added so that the EGT level was 4.0 ppm or higher as having a full-bodied taste.

Claims (3)

The following steps a) to d):
a) preparing a beverage preparation;
b) adding 0.3 to 440 ppm (w/w) of L-ergothioneine to the beverage preparation;
Step c) adjusting the pH (at 20° C.) of the beverage preparation to between 5.0 and 7.5; and Step d) heating the beverage preparation containing L-ergothioneine.
The heating conditions in the step d) are such that, when the heating temperature (° C.) is X and the heating time (minutes) is Y, the heating conditions satisfy the following formula (1):
Formula (1) Y≧34×(X−60) ^−1.1 (where 61≦X≦150)
A method for producing a beverage, which satisfies the above. The following steps a) and x) to z):
a) preparing a beverage preparation;
Step x of preparing an L-ergothioneine-containing solution;
a step y) of heating the L-ergothioneine-containing solution to prepare a heated L-ergothioneine solution; and a step z) of mixing the heated L-ergothioneine solution with the beverage preparation so that the L-ergothioneine concentration in the solution is 0.3 to 440 ppm (w/w).
The heating conditions in the step y) are such that, when the heating temperature (° C.) (minutes) is X and the heating time (minutes) is Y, the heating conditions satisfy the following formula (1):
Formula (1) Y≧34×(X−60) ^−1.1 (where 61≦X≦150)
and the pH (20°C) is 5.0 to 7.5. The method for producing a beverage according to claim 1 or 2, wherein the beverage contains 10 to 20,000 ppb of pyrazines.