Green tea beverage

Abstract

To provide a green tea beverage that gives a rich feel of umami while having reduced astringency, and strikes a balance between umami and astringency.SOLUTION: A green tea beverage contains non-polymerized catechin and acidic amino acid, with the content of the non-polymerized catechin being 350 mg / L or less, and the ratio of the non-polymerized catechin content to the acidic amino acid content (non-polymerized catechin content / acidic amino acid content) being 18 or more and 30 or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to green tea beverages. [Background technology]

[0002] Consumption of green tea beverages is increasing due to the growing health consciousness of consumers. However, green tea has a unique bitter and astringent taste, which some consumers dislike.

[0003] Therefore, research is being conducted on green tea beverages with reduced bitterness and astringency.For example, Patent Document 1 discloses a green tea beverage having both a refreshing feeling and a green tea feeling, the green tea beverage having an absorbance of 0.35 or less at 420 nm, a content of non-polymer catechins in the green tea beverage being 0.01 ppm or more and 300 ppm or less, a content of amino acids in the green tea beverage being 0.01 ppm or more and 500 ppm or less, a content of quinic acid in the green tea beverage being 0.005 ppm or more and 500 ppm or less, a ratio of the content of the quinic acid to the content of the non-polymer catechins being 0.5 or more, and a ratio of the content of the quinic acid to the content of the amino acids being 0.5 or more. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-187276 A Summary of the Invention [Problem to be solved by the invention]

[0005] The bitter and astringent taste of green tea is mainly derived from tannins such as non-polymerized catechins. By reducing the amount of tannins in green tea, the bitter and astringent taste can be suppressed and green tea with a refreshing taste can be obtained. However, reducing the amount of tannins also impairs the inherent flavor of green tea, making it taste watery and unsatisfying to drink.

[0006] To provide a green tea beverage which has a sufficient delicious taste while suppressing bitterness and astringency, and has a good balance between the bitterness and astringency and the delicious taste. [Means for solving the problem]

[0007] The present invention relates to a green tea beverage containing non-polymerized catechins and acidic amino acids, in which the content of non-polymerized catechins is 350 mg / L or less and the ratio of the content of non-polymerized catechins to the content of acidic amino acids (content of non-polymerized catechins / content of acidic amino acids) is 18 or more and 30 or less.

[0008] The green tea beverage according to the present invention has a low content of non-polymerized catechins, which reduces bitterness and astringency, while the ratio of the contents of acidic amino acids and non-polymerized catechins within a specific range provides a sufficient umami taste and an excellent balance between the bitterness and astringency and the umami taste. Furthermore, since the green tea beverage has a good balance between the bitterness and astringency and the umami taste, it has the effect of being satisfying to drink and not feeling watery.

[0009] The green tea beverage preferably has a non-polymerized catechin content of 155 mg / L or more and 350 mg / L or less, which provides a stronger umami flavor and a better balance between the bitterness, astringency, and umami flavor.

[0010] In the green tea beverage, the ratio of the content of non-polymerized catechins to the content of acidic amino acids is preferably from 18 to 27. This allows for a stronger sense of umami, and a better balance between the bitterness, astringency, and umami.

[0011] The green tea beverage preferably contains monosaccharides, disaccharides and trisaccharides, with the total content of monosaccharides, disaccharides and trisaccharides being 100 mg / L or more, which not only makes the above-mentioned effects on umami and bitterness / astringency more pronounced, but also allows the inherent sweetness of green tea to be fully felt and provides an excellent balance between the bitterness / astringency and sweetness. Effect of the Invention

[0012] According to the present invention, it is possible to provide a green tea beverage which has a good balance between the bitterness, astringency and umami taste and yet has a sufficient umami taste while suppressing the bitterness and astringency. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Hereinafter, an embodiment of the present invention will be described in detail. However, the present invention is not limited to the following embodiment.

[0014] The green tea beverage of this embodiment contains non-polymerized catechins and acidic amino acids, the content of non-polymerized catechins is 350 mg / L or less, and the ratio of the content of non-polymerized catechins to the content of acidic amino acids (content of non-polymerized catechins / content of acidic amino acids) is 18 or more and 30 or less.

[0015] In the present specification, the term "green tea beverage" refers to any beverage generally classified as a green tea beverage, and is a liquid containing a green tea extract obtained by extracting green tea leaves. The green tea beverage may contain, in addition to the green tea extract, various additives, water, and the like. The green tea leaves may be green tea as defined in the "Green Tea Labeling Standards" (revised on March 18, 2019) by the Japan Tea Association, i.e., tea leaves (including some stems) produced in a state suitable for consumption after inactivating enzymes in the tea leaves by steaming or pan-frying, and may be, for example, sencha, gyokuro, kabusecha, tamaryokucha, bancha, or hocha. The green tea extract may be in a liquid form or in a solid form such as a powder form. The green tea extract may be a concentrate of an extract obtained by extracting green tea leaves. The green tea beverage according to the present embodiment may be an alcoholic beverage (a beverage having an alcohol content of 1 v / v% or more) or a non-alcoholic beverage (a beverage having an alcohol content of less than 1 v / v%). The green tea beverage according to this embodiment may be a carbonated beverage.

[0016] In this specification, "non-polymerized catechin" refers to catechins that are not polymerized. Specifically, catechins are gallocatechin (GC), epigallocatechin (EGC), catechin (C), epigallocatechin gallate (EGCG), epicatechin (EC), gallocatechin gallate (GCG), epicatechin gallate (ECG) and catechin gallate (CG). The content of non-polymerized catechin is the total content of these eight compounds.

[0017] The content of non-polymerized catechin in the green tea beverage according to the present embodiment is 350mg / L or less. There is no particular limit to the lower limit of the content of non-polymerized catechin, but from the viewpoint of reducing bitterness and astringency to be refreshing while still being able to feel the bitterness and astringency, it may be 100mg / L or more, 125mg / L or more, or 150mg / L or more. In addition, from the viewpoint of feeling the umami more and having a better balance between the bitterness and astringency and the umami, it may be 155mg / L or more, 175mg / L or more, 200mg / L or more, 225mg / L or more, or 250mg / L or more.

[0018] The content of non-polymerized catechins can be adjusted, for example, by adding non-polymerized catechins to a green tea beverage, by removing non-polymerized catechins from a green tea beverage, by appropriately setting the extraction conditions for green tea leaves (e.g., the amount of tea leaves used, extraction temperature, extraction time), or by a combination of these methods.

[0019] The content of non-polymerized catechins can be measured, for example, by using high performance liquid chromatography (HPLC) according to the method described in the Examples below.

[0020] As used herein, the term "acidic amino acids" refers to aspartic acid and glutamic acid. The content of acidic amino acids is the total content of aspartic acid and glutamic acid.

[0021] The green tea beverage according to this embodiment has a ratio of the content of non-polymerized catechins to the content of acidic amino acids (hereinafter simply referred to as the "content ratio") of 18 to 30. When the content ratio is within this range, the green tea beverage has a reduced bitter and astringent taste while still having a sufficient umami taste, and has an excellent balance between the bitter and astringent taste and the umami taste. Specifically, the content ratio is a value calculated by the following formula. Content ratio = content of non-polymerized catechin (mg / L) / content of acidic amino acid (mg / L)

[0022] From the viewpoint that the above-mentioned effects are more significantly exhibited, the content ratio may be 18.5 or more, 19 or more, 19.5 or more, 20 or more, or 20.5 or more. From the same viewpoint, the content ratio may be 29.5 or less, 29 or less, 28.5 or less, 28 or less, 27.5 or less, or 27 or less.

[0023] The content ratio can be adjusted, for example, by adding non-polymerized catechins and / or acidic amino acids to a green tea beverage, by removing non-polymerized catechins and / or acidic amino acids from a green tea beverage, by appropriately setting the extraction conditions for green tea leaves (e.g., the amount of tea leaves used, extraction temperature, extraction time), or by a combination of these methods.

[0024] The content of acidic amino acids can be measured, for example, by using an amino acid analyzer according to the method described in the Examples below.

[0025] The green tea beverage according to this embodiment contains monosaccharides, disaccharides and trisaccharides, and the total content of monosaccharides, disaccharides and trisaccharides is preferably 100 mg / L or more. When the total content of monosaccharides, disaccharides and trisaccharides is within this range, the above-mentioned effects on umami and bitterness / astringency become more pronounced, the inherent sweetness of green tea is fully felt and the bitterness / astringency and sweetness are well balanced.

[0026] As used herein, "monosaccharide" refers to glucose and fructose, i.e., the monosaccharide content is the total content of glucose and fructose.

[0027] A disaccharide refers to a sugar in which two monosaccharide molecules are dehydrated and condensed to form a glycosidic bond to form one molecule. In this specification, "disaccharide" refers to sucrose. That is, the content of disaccharide is the content of sucrose.

[0028] Trisaccharide means a sugar in which three monosaccharide molecules are dehydrated and condensed to form a glycosidic bond into one molecule. In this specification, "trisaccharide" means raffinose. In other words, the content of trisaccharide is the content of raffinose.

[0029] The total content of monosaccharides, disaccharides and trisaccharides may be 100 mg / L or more, 110 mg / L or more, 120 mg / L or more, 125 mg / L or more, or 130 mg / L or more, from the viewpoint of the above-mentioned effects on sweetness and bitterness / astringency being significantly exhibited. The total content of monosaccharides, disaccharides and trisaccharides may be, for example, 250 mg / L or less, 240 mg / L or less, 230 mg / L or less, 220 mg / L or less, or 210 mg / L or less. From the viewpoint of the above-mentioned effects on sweetness and bitterness / astringency being significantly exhibited, the total content of monosaccharides, disaccharides and trisaccharides may be 200 mg / L or less, 190 mg / L or less, 180 mg / L or less, 170 mg / L or less, 160 mg / L or less, or 155 mg / L or less.

[0030] The total content of monosaccharides, disaccharides, and trisaccharides may be represented by the sugars mainly contained in the green tea extract as described above. That is, the green tea beverage according to the present embodiment may have a total content of glucose, fructose, sucrose, and raffinose within the above range, thereby achieving the same effect.

[0031] The total content of monosaccharides, disaccharides and trisaccharides can be adjusted, for example, by adding monosaccharides, disaccharides and / or trisaccharides to the green tea beverage, by removing monosaccharides, disaccharides and / or trisaccharides from the green tea beverage, by appropriately setting the extraction conditions for the green tea leaves (e.g., the amount of tea leaves used, the extraction temperature, the extraction time), or by a combination of these methods.

[0032] The total content of monosaccharides, disaccharides and / or trisaccharides can be measured, for example, using high performance liquid chromatography (HPLC) according to the method described in the Examples below.

[0033] The tannin content of the green tea beverage according to this embodiment may be, for example, 25 mg / L or more and 45 mg / L or less. Furthermore, the weight ratio of non-polymerized catechins to tannins (non-polymerized catechins (mg / L) / tannins (mg / L)) of the green tea beverage according to this embodiment may be, for example, 0.70 or more and 0.85 or less. The tannin content is a value measured according to the Official Analysis Method for Green Tea ("Official Analysis Method for Tea", Report of the Tea Industry Research Institute, No. 6, pp. 169-170, 1970).

[0034] The pH of the green tea beverage according to the present embodiment may be, for example, 5.0 or more, and more preferably 5.5 or more. The pH of the green tea beverage according to the present embodiment may be, for example, 8.0 or less, or 7.5 or less. More preferably, the pH of the green tea beverage according to the present embodiment may be 7.0 or less, or 6.5 or less.

[0035] The green tea beverage according to this embodiment may contain additives known for beverages to the extent that they do not affect the effects of the present invention. The additives are not particularly limited, but examples thereof include antioxidants, flavorings, inorganic salts, coloring agents, preservatives, acidulants, pH adjusters, etc. These additives may be blended alone or in combination.

[0036] The green tea beverage according to this embodiment can be provided in a container. The container may be any container that can be sealed, and may be, for example, a metal (e.g., aluminum or steel) can or barrel container, a glass container, a plastic bottle container, a paper container, a pouch container, or the like. Among these, glass containers and plastic bottle containers, which are transparent containers through which the color of the green tea beverage can be seen, are preferred. The capacity of the container is not particularly limited, and any currently available containers may be used.

[0037] The green tea beverage according to the present embodiment can be obtained, for example, by a production method including at least an extraction step in which green tea leaves are contacted with an extraction solvent to obtain a green tea extract. The content of non-polymerized catechins and acidic amino acids in the green tea beverage can be adjusted, for example, by performing the extraction step under extraction conditions (described later) that shorten the extraction time compared to the amount of green tea leaves used. In addition, the content of non-polymerized catechins and acidic amino acids in the green tea beverage can be adjusted by mixing green tea extracts obtained under different extraction conditions, adding or removing non-polymerized catechins and acidic amino acids to the obtained green tea extract to adjust the content of non-polymerized catechins and acidic amino acids in the green tea beverage, or combining these to adjust the content of non-polymerized catechins and acidic amino acids in the green tea beverage. The content of monosaccharides, disaccharides, and trisaccharides can be adjusted in the same manner.

[0038] The extraction step is a step of contacting green tea leaves with an extraction solvent to obtain a green tea extract. The manner of contacting the extraction solvent with the green tea leaves is not particularly limited as long as the green tea extract is obtained, and an example of the contacting is soaking the green tea leaves in the extraction solvent.

[0039] The extraction solvent used in the extraction step is usually water. The temperature of the water may be, for example, 30 to 100°C, preferably 40 to 80°C, and more preferably 45 to 65°C.

[0040] The ratio (bath ratio) of the weight of the extraction solvent to the weight of the green tea leaves may be, for example, 10 to 50 times, preferably 20 to 40 times, and more preferably 30 to 40 times.

[0041] The extraction time may be, for example, from 1 minute to 50 minutes, preferably from 1.5 minutes to 30 minutes, more preferably from 1.5 minutes to 10 minutes, and even more preferably from 1.5 minutes to 6 minutes. The extraction time is the time during which the green tea leaves are in contact with the extraction solvent.

[0042] In one embodiment, the content of non-polymerized catechins and the ratio of the content of non-polymerized catechins to the content of acidic amino acids can be adjusted within the range specified for the green tea beverage of the present invention by shortening the extraction time compared to the amount of green tea leaves used. In this embodiment, the extraction step may be, for example, a step of immersing green tea leaves in water at 45 to 55°C (bath ratio 30 to 40 times) for 1.5 to 6 minutes to obtain a green tea extract. The extraction time (immersion time) is preferably 2 to 5.5 minutes. According to a production method including such an extraction step, it is often possible to omit the effort of further adjusting the contents of non-polymerized catechins and acidic amino acids in the green tea beverage.

[0043] In the extraction step, it is preferable to separate the extraction solvent (green tea extract) from the green tea leaves immediately after the extraction time has elapsed. Separation of the extraction solvent (green tea extract) from the green tea leaves can be carried out, for example, by filtration.

[0044] The production method according to this embodiment may further include an adding step and a post-treatment step after the extraction step.

[0045] The adding step is a step of adding water and / or additives to the green tea extract as necessary. The additives that can be used are those mentioned above. The adding step can be carried out, for example, by adding the green tea extract and, as necessary, water and / or additives to a mixing tank and mixing them. In addition, in the adding step, non-polymerized catechins and / or acidic amino acids may be added as necessary to adjust the contents of non-polymerized catechins and acidic amino acids in the green tea beverage.

[0046] The post-treatment step may selectively include, for example, sterilization of the green tea beverage, filling of the green tea beverage into containers, etc., as required. EXAMPLES

[0047] The present invention will be described in more detail below with reference to examples, although the present invention is not limited to the following examples.

[0048] [Test Example: Preparation and Evaluation of Green Tea Beverage] (Preparation of Green Tea Beverage) A green tea beverage was prepared by extracting green tea (tea leaves) with hot water under the conditions shown in Table 1.

[0049] The pH of the prepared green tea beverages was measured using a pH meter (F-72, manufactured by Horiba, Ltd.) The pH of all the green tea beverages was 6.2 to 6.3.

[0050] (Content Analysis) The content of various components in each green tea beverage was analyzed using the methods described below. The analysis results are shown in Table 1.

[0051] <Monosaccharides and disaccharides> Each green tea beverage was filtered through a 0.45 μm cellulose acetate filter and analyzed under the following conditions. Quantitative analysis was performed using the absolute calibration curve method. Equipment used: Ultimate3000 LC (Thermo Fisher Scientific) Detector: Corona CAD detector Column: Asahipak NH2P-50 (4.6 x 250 mm) (Shodex) Mobile phase A: Ultrapure water Mobile phase B: Acetonitrile Column temperature: 40℃ Injection volume: 5μL Flow rate: 1mL / min Gradient B: 75% (0 min)-75% (30 min)-10% (45 min)-10% (60 min) The only monosaccharides detected were fructose and glucose, the only disaccharide detected was sucrose, and the only trisaccharide detected was raffinose.

[0052] <Non-polymerized catechin> Each green tea beverage was diluted 10 times with ultrapure water and filtered through a 0.45 μm hydrophilic mixed cellulose ester filter to prepare a measurement sample. For the measurement, an HPLC (Shimadzu Prominence, manufactured by Shimadzu Corporation) was used. The measurement conditions were as follows. Column: WakoPak Navi C18-5, 4.6 x 150 mm (Fujifilm Wako Pure Chemical Industries, Ltd.) Injection volume: 20μL Flow rate: 1mL / min Mobile phase A: ultrapure water: phosphoric acid: acetonitrile = 1000: 2.5: 2.5 (v / v / v) Mobile phase B: methanol 0 to 2 minutes: Mobile phase A 93.3%, Mobile phase B 6.7% → 37 minutes: Mobile phase A 73.3%, Mobile phase B 26.7% → 37.1 to 47 minutes: Mobile phase A 0%, Mobile phase B 100% → 47.1 to 55 minutes: Mobile phase A 93.3%, Mobile phase B 6.7% Stop time: 55 minutes Post time: 0 minutes Oven temperature: 40℃ UV detector wavelength: Measurement 242nm and 272nm Fluorescence detector: Excitation wavelength 280 nm, fluorescence wavelength 310 nm Quantitative method: Absolute calibration curve method In Table 1, the content of non-polymerized catechins is the total content of gallocatechin (GC), epigallocatechin (EGC), catechin (C), epigallocatechin gallate (EGCG), epicatechin (EC), gallocatechin gallate (GCG), epicatechin gallate (ECG) and catechin gallate (CG).

[0053] <Amino acids> Each green tea beverage was diluted 2-fold with ultrapure water and filtered through a 0.45 μm cellulose acetate filter to prepare a measurement sample. The content of each amino acid was quantified using an amino acid analyzer (JCL-500 / V2, manufactured by JEOL Ltd.). In Table 1, the acidic amino acid content is the total content of aspartic acid and glutamic acid, and the amino acid content is the total content of all amino acids including acidic amino acids.

[0054] <Tannin> The tannin content was measured according to the official analytical method for green tea ("Official Analytical Method for Tea", Report of the Tea Research Institute, No. 6, pp. 169-170, 1970).

[0055] (Sensory evaluation) Each green tea beverage was subjected to a sensory evaluation by a trained panel of five members. The sensory evaluation was conducted by scoring the following relative values ​​between each green tea beverage for the evaluation items of "bitterness / astringency," "umami," "balance of bitterness / astringency and umami," and "sweetness" and "balance of bitterness / astringency and sweetness" when each green tea beverage was drunk (each evaluation item was scored in 0.5-point increments between 1 and 5 points). For the evaluation item of "bitterness / astringency," the score for the green tea beverage of Comparative Example 2 was fixed at 5 points. Bitterness: 1 point (weak) to 5 points (strong) Taste: 1 point (weak) to 5 points (strong) Balance of bitterness and umami: 1 point (unbalanced) to 5 points (well balanced) Sweetness: 1 point (weak) to 5 points (strong) Bitterness and sweetness balance: 1 point (unbalanced) to 5 points (well balanced) For the evaluation item "balance of bitterness, astringency and umami," a product in which both the bitterness, astringency and umami tastes were clearly perceived was rated as "balanced," whereas a product in which one of the bitterness, astringency and umami tastes was relatively strong and the other taste was difficult to sense was rated as "unbalanced." Similarly, for the evaluation item "balance of bitterness, astringency and sweetness," a product in which both the bitterness, astringency and sweetness were clearly perceived was rated as "balanced," whereas a product in which one of the bitterness, astringency and sweetness tastes was relatively strong and the other taste was difficult to sense was rated as "unbalanced."

[0056] For each evaluation item, the average score given by five trained panelists was used as the evaluation result. The evaluation results are shown in Table 1. [Table 1]

[0057] The green tea beverages of Examples 1 to 5, in which the content of non-polymerized catechins was 350 mg / L or less and the ratio of the content of non-polymerized catechins to the content of acidic amino acids (content of non-polymerized catechins / content of acidic amino acids) was 18 to 30, had reduced bitterness and astringency, had a sufficient umami flavor, and had an excellent balance between bitterness and astringency, compared to the green tea beverages of Comparative Examples 1 to 3, which did not satisfy these conditions.

Claims

1. It contains non-polymerized catechins and acidic amino acids, The non-polymerized catechin content is 275 mg / L or less, and A green tea beverage in which the ratio of non-polymerized catechins to acidic amino acids (non-polymerized catechin content / acidic amino acid content) is between 18 and 30.

2. A product containing monosaccharides, disaccharides and trisaccharides, The green tea beverage according to claim 1, wherein the total content of monosaccharides, disaccharides, and trisaccharides is 100 mg / L or more.