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

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

Background Art

[0002] Due to the increasing health consciousness of consumers, the consumption of green tea beverages is increasing. On the other hand, green tea has a unique bitter and astringent taste, and there are quite a few consumers who dislike it.

[0003] Therefore, studies on green tea beverages with reduced bitter and astringent tastes have also been underway. For example, Patent Document 1 discloses a green tea beverage having both a refreshing feeling and a green tea feeling, wherein the absorbance at 420 nm is 0.35 or less, the content of non-polymer catechins in the green tea beverage is 0.01 ppm or more and 300 ppm or less, the content of amino acids in the green tea beverage is 0.01 ppm or more and 500 ppm or less, the content of quinic acid in the green tea beverage is 0.005 ppm or more and 500 ppm or less, the ratio of the content of quinic acid to the content of non-polymer catechins is 0.5 or more, and the ratio of the content of quinic acid to the content of amino acids is 0.5 or more.

Prior Art Documents

[0007] The present invention relates to a green tea beverage containing non-polymerized catechins and acidic amino acids, wherein the non-polymerized catechin content is 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) is 18 to 30.

[0008] The green tea beverage according to the present invention has a reduced bitter taste due to its low content of non-polymerized catechins, while the ratio of acidic amino acids to non-polymerized catechins is within a specific range, resulting in a sufficient umami flavor and an excellent balance between bitterness, astringency, and umami. Furthermore, because of this good balance between bitterness, astringency, and umami, the green tea beverage is satisfying to drink and does not taste watery.

[0009] The above-mentioned green tea beverage preferably contains non-polymerized catechins of 155 mg / L to 350 mg / L. This enhances the umami flavor and improves the balance between bitterness and umami.

[0010] The above-mentioned green tea beverage preferably has a ratio of non-polymerized catechins to acidic amino acids of 18 to 27. This results in a more pronounced umami flavor and a better balance between bitterness and umami.

[0011] The above-mentioned green tea beverage contains monosaccharides, disaccharides, and trisaccharides, and preferably the total content of monosaccharides, disaccharides, and trisaccharides is 100 mg / L or more. This makes the effects on umami and bitterness more pronounced, allows the natural sweetness of green tea to be fully appreciated, and results in a well-balanced taste between bitterness and sweetness. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a green tea beverage that has sufficient umami while suppressing bitterness and astringency, and that has a good balance between bitterness and umami. [Modes for carrying out the invention]

[0013] The embodiments for carrying out the present invention will be described in detail below. However, the present invention is not limited to the following embodiments.

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

[0015] In this specification, "green tea beverage" refers to any liquid generally classified as a green tea beverage, and includes a green tea extract obtained by extracting green tea leaves. In addition to the green tea extract, the green tea beverage may also contain, for example, various additives, water, etc. The green tea leaves may be green tea as defined by the Japan Tea Association's "Green Tea Labeling Standards" (revised March 18, 2019), that is, tea leaves (including some stems) that have been processed to a state suitable for consumption after inactivating enzymes in the tea leaves by methods such as steaming or pan-frying, for example, sencha, gyokuro, kabusecha, gyokuro, bancha, or hōcha. The green tea extract may be in liquid form or in solid form such as powder. The green tea extract may also be a concentrate of the extract obtained by extracting green tea leaves. The green tea beverage according to this embodiment may be an alcoholic beverage (a beverage with an alcohol content of 1 v / v% or more) or a non-alcoholic beverage (a beverage with an alcohol content of less than 1 v / v%). Furthermore, the green tea beverage according to this embodiment may be a carbonated beverage.

[0016] In this specification, "non-polymerized catechin" refers to catechins that have not been polymerized. Specifically, catechins include 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 non-polymerized catechin content in the green tea beverage according to this embodiment is 350 mg / L or less. There is no particular lower limit to the non-polymerized catechin content, but from the viewpoint of reducing bitterness and astringency to a refreshing taste while still allowing the bitterness and astringency to be felt, it may be 100 mg / L or more, 125 mg / L or more, or 150 mg / L or more. Furthermore, from the viewpoint of allowing the umami to be felt more and achieving a better balance between bitterness and umami, it may be 155 mg / L or more, 175 mg / L or more, 200 mg / L or more, 225 mg / L or more, or 250 mg / L or more.

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

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

[0020] In this specification, "acidic amino acids" refers to aspartic acid and glutamic acid. The acidic amino acid content 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, also simply referred to as "content ratio") of 18 or more and 30 or less. By having the content ratio within this range, while the astringency is reduced, a sufficient umami can be felt, and it becomes a green tea beverage with an excellent balance between astringency and umami. Specifically, the content ratio is a value calculated by the following formula. Content ratio = Content of non-polymerized catechins (mg / L) / Content of acidic amino acids (mg / L)

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

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

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

[0025] The green tea beverage according to this embodiment contains monosaccharides, disaccharides and trisaccharides, and it is preferable that the total content of monosaccharides, disaccharides and trisaccharides is 100 mg / L or more. When the total content of monosaccharides, disaccharides and trisaccharides is within this range, in addition to making the above effects regarding umami and astringency more显著, the original sweetness of green tea can be充分 felt, and it becomes excellent in the balance between astringency and sweetness.

[0026] In this specification, "monosaccharide" means glucose and fructose. That is, the monosaccharide content is the total content of glucose and fructose.

[0027] A disaccharide refers to a sugar formed when two monosaccharide molecules undergo dehydration condensation to form a glycosidic bond, resulting in a single molecule. In this specification, "disaccharide" refers to sucrose. That is, the disaccharide content is the sucrose content.

[0028] A trisaccharide refers to a sugar formed when three monosaccharide molecules undergo dehydration condensation to form a glycosidic bond, resulting in a single molecule. In this specification, "trisaccharide" refers to raffinose. Therefore, the trisaccharide content is the raffinose content.

[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 achieving the aforementioned significant effects on sweetness and bitterness. 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 achieving the aforementioned significant effects on sweetness and bitterness, 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 this embodiment may have a total content of glucose, fructose, sucrose, and raffinose within the above range. This will produce 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 green tea beverages, by removing monosaccharides, disaccharides, and / or trisaccharides from green tea beverages, by appropriately setting the extraction conditions for green tea leaves (e.g., amount of tea leaves used, extraction temperature, extraction time), and by methods combining these.

[0032] The total content of monosaccharides, disaccharides, and / or trisaccharides can be measured, for example, using high-performance liquid chromatography (HPLC) as 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. Note that the tannin content is a value 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).

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

[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 include antioxidants, flavorings, inorganic salts, colorants, preservatives, acidulants, and pH adjusters. These additives can be blended individually or in combination.

[0036] The green tea beverage according to this embodiment can be provided in a container. The container can be any airtight container, such as a metal (e.g., aluminum, steel) can or barrel container, a glass container, a PET bottle, a paper container, a pouch container, etc. Among these, glass containers and PET bottles, which are transparent containers that allow the color of the green tea beverage to be seen, are preferred. Furthermore, the capacity of the container is not particularly limited, and any currently available containers can be used.

[0037] The green tea beverage according to this embodiment can be obtained, for example, by a manufacturing method that includes at least an extraction step of contacting green tea leaves 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 carrying out the extraction step under extraction conditions (described later) that shorten the extraction time compared to the amount of green tea leaves used. Alternatively, 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, by adding or removing non-polymerized catechins and acidic amino acids from the obtained green tea extract, or by combining these methods. The content of monosaccharides, disaccharides, and trisaccharides can be adjusted in the same manner.

[0038] The extraction process involves contacting green tea leaves with an extraction solvent to obtain a green tea extract. The manner in which the extraction solvent and green tea leaves come into contact is not particularly limited as long as a green tea extract is obtained; for example, immersing the green tea leaves in the extraction solvent is one example.

[0039] The extraction solvent used in the extraction process 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 of the weight of the extraction solvent to the weight of the green tea leaves (bath ratio) 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, 1 minute or more and 50 minutes or less, preferably 1.5 minutes or more and 30 minutes or less, more preferably 1.5 minutes or more and 10 minutes or less, and even more preferably 1.5 minutes or more and 6 minutes or less. Note that the extraction time is the time that the green tea leaves are in contact with the extraction solvent.

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

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

[0044] The manufacturing method according to this embodiment may further include an addition step and a post-processing step after the extraction step.

[0045] The addition step involves adding water and / or additives to the green tea extract as needed. The additives mentioned above can be used. The addition step can be carried out, for example, by adding the green tea extract, along with water and / or additives as needed, to a mixing tank and mixing. Furthermore, in the addition step, non-polymerized catechins and / or acidic amino acids may be added as needed to adjust the content of non-polymerized catechins and acidic amino acids in the green tea beverage.

[0046] The post-processing steps may include, for example, sterilization of the green tea beverage and filling of the green tea beverage into containers, which may be selectively performed as needed. [Examples]

[0047] The present invention will be described more specifically below based on examples. However, the present invention is not limited to the following examples.

[0048] [Example of test: Preparation and evaluation of green tea beverage] (Preparation of green tea beverages) Green tea beverages were 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 between 6.2 and 6.3.

[0050] (Analysis of content) The content of various components in each green tea beverage was analyzed using the method 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 (manufactured by 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. The only trisaccharide detected was raffinose.

[0052] <Non-polymerized catechins> Each green tea beverage was diluted 10-fold with ultrapure water and filtered through a 0.45 μm hydrophilic mixed cellulose ester filter to prepare the sample for measurement. HPLC (Shimadzu Prominence, Shimadzu Corporation) was used for the measurement. The measurement conditions were as follows: Column: WakoPak Navi C18-5, 4.6 x 150 mm (manufactured by 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 wavelengths: Measured at 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 2:1 with ultrapure water and filtered through a 0.45 μm cellulose acetate filter to prepare the sample for measurement. The content of each amino acid was quantified using an amino acid analyzer (JCL-500 / V2, manufactured by JEOL Ltd.). Note that in Table 1, the acidic amino acid content refers to the total content of aspartic acid and glutamic acid. The amino acid content refers to 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 sensory evaluation by a panel of five trained individuals. The sensory evaluation assessed each green tea beverage based on the following relative values: "bitterness," "umami," "balance between bitterness and umami," and "sweetness" (each item was scored in increments of 0.5 points between 1 and 5). For the "bitterness" evaluation item, the score for Comparative Example 2's green tea beverage was fixed at 5 points. Bitterness / Astringency: 1 point (weak) to 5 points (strong) Umami: 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) Balance of bitterness and sweetness: 1 point (unbalanced) to 5 points (well-balanced) Furthermore, for the "balance of bitterness and umami" evaluation item, a product where both bitterness and umami were clearly perceived was evaluated as "well-balanced," while a product where one of the bitterness or umami flavors was relatively strong and the other flavor was difficult to perceive was evaluated as "unbalanced." Similarly, for the "balance of bitterness and sweetness" evaluation item, a product where both bitterness and sweetness were clearly perceived was evaluated as "well-balanced," while a product where one of the bitterness or sweetness was relatively strong and the other flavor was difficult to perceive was evaluated as "unbalanced."

[0056] For each evaluation item, the average score of five trained panel members 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, which contained 350 mg / L or less of non-polymerized catechins and had a ratio of non-polymerized catechins to acidic amino acids (non-polymerized catechin content / acidic amino acid content) of 18 to 30, exhibited reduced bitterness and astringency, a sufficient umami flavor, and a superior balance between bitterness and umami compared to the green tea beverages of Comparative Examples 1 to 3, which did not meet these conditions.

Claims

1. It contains non-polymerized catechins and acidic amino acids, The non-polymerized catechin content is 350 mg / L or less, and A green tea beverage in which the ratio of non-polymerized catechin content to acidic amino acid content (non-polymerized catechin content / acidic amino acid content) is 18 or more and 21.0 or less.

2. The green tea beverage according to claim 1, wherein the non-polymerized catechin content is 155 mg / L or more and 350 mg / L or less.

3. It contains non-polymerized catechins and acidic amino acids, The non-polymerized catechin content is 350 mg / L or less. 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. It contains monosaccharides, disaccharides and trisaccharides, A green tea beverage in which the total content of monosaccharides, disaccharides, and trisaccharides is between 100 mg / L and 200 mg / L.

4. The green tea beverage according to claim 3, wherein the non-polymerized catechin content is 155 mg / L or more and 350 mg / L or less.

5. The green tea beverage according to claim 3 or 4, wherein the ratio of the content of non-polymerized catechins to the content of acidic amino acids is 18 or more and 27 or less.

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