Bottled black soy tea beverage and method for suppressing astringent taste of bottled black soy tea beverage

Abstract

To provide a bottled black soy tea beverage that suppresses astringency and further inhibits oil separation occurring over time.SOLUTION: There is provided a bottled black soy tea beverage containing at least tannins, isoflavones, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, and 2,6-dimethylpyrazine. The bottled black soy tea beverage contains water-soluble isoflavones as the main component of isoflavones. The ratio of isoflavone content to tannin content (isoflavones / tannins) ranges from 0.5 to 6.0 and the total mass content of 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, and 2,6-dimethylpyrazine is 260 ppb to 1500 ppb.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a packaged black bean tea beverage in which black bean tea obtained by extracting roasted black soybeans or a black bean tea beverage containing components thereof is filled into a container, and a method for suppressing the astringent taste of a packaged black bean tea beverage. [Background technology]

[0002] Kuromame (officially known as "black soybeans") is one of many types of soybeans, and refers to soybeans with black seed coats. They contain polyphenols, anthocyanins, and even isoflavones. The isoflavones contained in soybeans are mainly found in soybean germ and have a similar molecular structure and function to the female hormone estrogen. As a result, they are said to be effective in improving menstrual irregularities, preventing osteoporosis and breast cancer, as well as improving skin, whitening, and breast enhancement.

[0003] Black soybean tea is made by roasting black soybeans (also known as "kuromame"), crushing them as needed, and then extracting them with hot water. It is rich in polyphenols and anthocyanins, and is said to be effective in anti-aging, dieting, and alleviating menopausal symptoms.

[0004] Regarding the production method of black bean tea, Patent Document 1 discloses a method for producing black bean tea suitable for extraction in bean form, which includes a soaking process in which raw black soybeans are soaked in water or alkaline water while still in bean form to swell, a draining process in which the black soybeans are drained after the soaking process is complete, a roasting process in which hot air is blown onto the black soybeans after the draining process is complete to roast them at a roasting temperature of 160 to 240°C, and a cooling process in which the soybeans are forcibly cooled to below 70°C after the roasting process is complete.

[0005] Patent Document 2 also discloses a method for producing black bean tea, which comprises polishing black beans to separate them into black bean kernels and black bean skins, soaking the black bean kernels in water for a predetermined period of time to make them germinating active, followed by a cold water immersion process, a steaming process in which the kernels are steamed, a drying process, a roasting process, and a cooling process, while the black bean skins are mixed with the black bean kernels as they are or after the roasting process and then subjected to a cooling process. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-41638 [Patent Document 2] Japanese Patent Application Laid-Open No. 2006-158329 Summary of the Invention [Problem to be solved by the invention]

[0007] Black bean tea, which contains isoflavones, has a unique astringent taste due to the isoflavones, which was a problem to be solved when it came to flavoring packaged beverages. In addition, some of the isoflavones extracted from roasted black beans are poorly soluble in water, which reduces the clarity (transparency) of the beverage. Furthermore, because black bean tea is produced by extracting roasted black beans, oil may float to the surface, which was also an issue that needed to be resolved for a packaged beverage.

[0008] The object of the present invention is to provide a packaged black bean tea beverage that can suppress an astringent taste, has excellent clarity (transparency), and can also suppress oil floating that occurs over time, as well as a method for suppressing the astringent taste of a packaged black bean tea beverage. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention proposes the following aspects.

[0010] [1] A first aspect of the present invention is a packaged black bean tea beverage containing at least tannins, isoflavones, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine, It contains water-soluble isoflavones as the main component of isoflavones, The ratio of the mass of isoflavones to the mass of tannins (isoflavones / tannins) is 0.5 to 6.0, and The packaged black bean tea beverage has a total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine of 260 ppb to 1500 ppb.

[0011] [2] A second aspect of the present invention is a packaged black bean tea beverage according to the first aspect, wherein the mass content of the isoflavones is 20.0 mg / 100 ml or less. [3] A third aspect of the present invention is a packaged black bean tea beverage according to the first or second aspect, wherein the mass content of the tannins is 15.0 mg / 100 ml or less. [4] A fourth aspect of the present invention is a packaged black bean tea beverage according to any one of the first to third aspects, wherein the ratio of the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine to the soluble solids content (Brix) of the packaged black bean tea beverage (total dimethylpyrazines / Brix) is 500 or more. [5] A fifth aspect of the present invention is a packaged black bean tea beverage according to any one of the first to fourth aspects, wherein the guaiacol content by mass is 118 ppb or less.

[0012] [6] A sixth aspect of the present invention is a method for suppressing an astringent taste in a packaged black bean tea beverage containing at least tannins, isoflavones, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine, comprising: The ratio of the mass of isoflavones to the mass of tannins (isoflavones / tannins) is adjusted to 0.5 to 6.0, and A method for suppressing the astringent taste of a packaged black bean tea beverage, characterized by adjusting the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine to 260 ppb to 1500 ppb. [Effects of the Invention]

[0013] The packaged black bean tea beverage proposed by the present invention can suppress astringent taste, has excellent clarity (transparency), and can also suppress oil floating that occurs over time. Therefore, it can be suitably provided as a packaged black bean tea beverage filled in, for example, a transparent container. DETAILED DESCRIPTION OF THE INVENTION

[0014] An example of an embodiment of the present invention will be described below, but the present invention is not limited to the embodiment described below.

[0015] <Black bean tea beverage of the present invention> A packaged black bean tea beverage according to one embodiment of the present invention (referred to as "the black bean tea beverage of the present invention") is a packaged black bean tea beverage containing at least isoflavones, tannins, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine.

[0016] In the present invention, a "black bean tea beverage" is a beverage that contains as its main ingredient an extract (referred to as "black bean tea") obtained by roasting black soybeans (black beans), grinding them as needed, and extracting them with water (including cold water, warm water, and hot water), or that contains the extracted components of the extract (black bean tea) as the main solid ingredient of the beverage, and is prepared by adding water, an isoflavone preparation, a pH adjuster, vitamin C, etc. as needed. In this case, "containing extract (black bean tea) as the main ingredient" means that the extract (black bean tea) accounts for 50% or more by mass of the beverage, and can be considered to account for 60% or more by mass of that, 70% or more by mass of that, 80% or more by mass of that, 90% or more by mass of that, or 95% or more by mass (including 100% by mass). Furthermore, "contains the extracted components of the extract (black bean tea) as the main solid component of the beverage" means that the components contained in the extract (black bean tea) account for 50% or more by mass of the solid components of the beverage, and can be considered to account for 60% or more by mass of that, 70% or more by mass of that, 80% or more by mass of that, 90% or more by mass of that, and 95% or more by mass (including 100% by mass).

[0017] Extracted components from roasted black beans typically include isoflavones, tannins, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, 2,6-dimethylpyrazine, and guaiacol, as well as carbohydrates, amino acids, potassium, magnesium, sodium, calcium, and phosphorus. The amounts of sugars, starch, and caffeine are below the detection limit. Among these, components that are thought to affect the flavor of black bean tea include isoflavones, tannins, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, 2,6-dimethylpyrazine, and guaiacol.

[0018] (Isoflavones) The black bean tea beverage of the present invention contains isoflavones. The term "isoflavones" specifically refers to some or all of the 12 types of isoflavones, namely, daidzin, glycitin, genistin, malonyldaidzin, malonylglycitin, malonylgenistin, acetyldaidzin, acetylglycitin, acetylgenistin, daidzein, glycitein, and genistein, and the "mass content of isoflavones" refers to the total mass content of the 12 types of isoflavones.

[0019] In the black bean tea beverage of the present invention, the main component of the isoflavones contained therein is preferably a water-soluble isoflavone, from the viewpoint of clarifying the black bean tea beverage of the present invention. Since some of the isoflavones extracted from roasted black beans are poorly soluble in water, in order to clarify the black bean tea beverage of the present invention, it is preferable that the main component of the isoflavones contained in the black bean tea beverage of the present invention is a water-soluble isoflavone. In this case, "the main component of isoflavones contained in the black bean tea beverage of the present invention" means a component that accounts for 50% or more by mass of the isoflavones contained in the black bean tea beverage of the present invention, preferably a component that accounts for 60% or more by mass of that, 70% or more by mass of that, 80% or more by mass of that, 90% or more by mass of that, and 95% or more by mass (including 100% by mass) of that. In order to make the main component of the isoflavones contained in the black bean tea beverage of the present invention water-soluble isoflavones, for example, insoluble isoflavones extracted from the raw material, roasted black beans, can be removed by filtration or the like, and an isoflavone preparation prepared to dissolve in water can be added. In addition, isoflavone preparations prepared to be soluble in water can usually be prepared from isoflavones derived from soybean germ.

[0020] The mass content of isoflavones in the black bean tea beverage of the present invention is preferably 20.0 mg / 100 ml or less, more preferably 18.0 mg / 100 ml or less, and even more preferably 15.0 mg / 100 ml or less, from the perspective of a guideline for daily intake. On the other hand, from the viewpoint of the functionality of isoflavones, the mass content of isoflavones is preferably 1.0 mg / 100 ml or more, more preferably 3.0 mg / 100 ml or more, even more preferably 5.0 mg / 100 ml or more, even more preferably 8.0 mg / 100 ml or more, and even more preferably 10.0 mg / 100 ml or more. To measure the mass content of isoflavones in the black bean tea beverage of the present invention, analysis can be carried out by high performance liquid chromatography (HPLC), as shown in the Examples below.

[0021] The isoflavones in the black bean tea beverage of the present invention include isoflavones derived from black beans, isoflavones derived from soybean germ, and isoflavones derived from soybeans. The mass content of isoflavones in the black bean tea beverage of the present invention can be adjusted by, for example, adjusting extraction conditions, adjusting filtration conditions, or adding an isoflavone preparation, but is not limited to these methods.

[0022] (Isoflavones / Tannins) In the black bean tea beverage of the present invention, the ratio of the mass of isoflavones contained to the mass of tannins contained (isoflavones / tannins) is preferably 0.5 to 6.0. In the black bean tea beverage of the present invention, if the ratio of isoflavones / tannins is 0.5 or more, the concentration of the black bean tea as a beverage is appropriate, and if it is 6.0 or less, the astringent taste specific to isoflavones is not felt, which is preferable. From this perspective, in the black bean tea beverage of the present invention, the ratio of isoflavones to tannins is preferably 0.5 or more, more preferably 1.0 or more, and even more preferably 1.5 or more, while it is preferably 6.0 or less, more preferably 5.6 or less, and even more preferably 5.0 or less.

[0023] In the black bean tea beverage of the present invention, the ratio of isoflavones to tannins can be adjusted by adjusting the extraction conditions or the amount of isoflavone preparation added, although the method is not limited to these.

[0024] To measure the mass of tannin contained in the black bean tea beverage of the present invention, analysis can be carried out using the ferric tartrate colorimetric method, as shown in the Examples below.

[0025] (tannins) In the black bean tea beverage of the present invention, the tannin content is preferably 17.0 mg / 100 ml or less, more preferably 15.0 mg / 100 ml or less, and even more preferably 10.0 mg / 100 ml or less, from the viewpoint of astringency. On the other hand, from the viewpoint of the concentration of black bean tea, the tannin content is preferably 0.2 mg / 100 ml or more, more preferably 0.8 mg / 100 ml or more, and even more preferably 1.4 mg / 100 ml or more.

[0026] In order to adjust the tannin content in the black bean tea beverage of the present invention, a method of adjusting the extraction conditions can be used, but the method is not limited to this.

[0027] (Dimethylpyrazine) In the black bean tea beverage of the present invention, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine are substances that produce roasted aroma, and the total mass content of these is preferably 260 ppb to 1500 ppb. In the black bean tea beverage of the present invention, if the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine is 260 ppb or more, it is preferable from the standpoint of the potency of the moderate roasted aroma of black bean tea, and if it is 1500 ppb or less, it is preferable from the standpoint of suppressing the oil floating that occurs over time and not sensing the burnt aroma of black bean tea. From this perspective, in the black bean tea beverage of the present invention, the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine is preferably 260 ppb or more, more preferably 350 ppb or more, and even more preferably 550 ppb or more, and on the other hand, it is preferably 1500 ppb or less, more preferably 1300 ppb or less, and even more preferably 1150 ppb or less.

[0028] In the black bean tea beverage of the present invention, methods for adjusting the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine include, but are not limited to, adjusting the roasting conditions of the raw material roasted black beans or adjusting the extraction conditions.

[0029] To measure the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine in the black bean tea beverage of the present invention, analysis can be performed using a gas chromatograph mass spectrometer (GC-MS) as shown in the examples described below.

[0030] (Dimethylpyrazine total / Brix) The black bean tea beverage of the present invention preferably has a ratio (total dimethylpyrazines / Brix) of the total mass content (ppb) of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine to its soluble solids content (Brix (mass%)) of 300 or more, more preferably 500 or more, and even more preferably 1000 or more, from the viewpoint of the duration of the roasted aroma that lingers in the mouth after drinking the black bean tea beverage. On the other hand, from the viewpoint of the intensity of the flavor of black bean tea, it is preferably 5000 or less, more preferably 1200 or less, and even more preferably 900 or less.

[0031] In the black bean tea beverage of the present invention, the total dimethylpyrazines / Brix can be adjusted by adjusting the extraction conditions or the roasting intensity of the raw material black beans, although methods are not limited to these.

[0032] (Guaiacol) In the black bean tea beverage of the present invention, from the viewpoint of suppressing bitterness, the guaiacol content by mass is preferably 130 ppb or less, more preferably 118 ppb or less, and even more preferably 95 ppb or less. On the other hand, from the viewpoint of the rich flavor of black bean tea, it is preferable that it is 10 ppb or more, and more preferably 15 ppb or more.

[0033] In the black bean tea beverage of the present invention, methods for adjusting the mass of guaiacol contained therein include, but are not limited to, adjusting the roasting conditions of the raw material, roasted black beans, or adjusting the extraction conditions.

[0034] To measure the guaiacol content in the black bean tea beverage of the present invention, analysis can be carried out using a gas chromatograph mass spectrometer (GC-MS), as shown in the Examples below.

[0035] (Soluble solid content (Brix)) The soluble solids content in the black bean tea beverage of the present invention is preferably 0.1 to 1.5% by mass. If the soluble solids content is 0.1% by mass or more and 1.5% by mass or less, the flavor of the black bean tea beverage of the present invention can be appropriately perceived, which is preferable. From this perspective, in the black bean tea beverage of the present invention, the soluble solids content is preferably 0.15% by mass or more or 1.30% by mass or less, more preferably 0.20% by mass or more or 0.90% by mass or less, and even more preferably 0.25% by mass or more or 0.85% by mass or less. In the black bean tea beverage of the present invention, the soluble solids content can be adjusted to the above range by, for example, adjusting the selection and mixing of raw materials, the extraction conditions, the amount of dilution water, and the amount of isoflavone preparation blended, but is not limited to this method.

[0036] In addition, the components obtained by extracting roasted black beans with water usually contain, in addition to the above-mentioned isoflavones, tannins, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, 2,6 dimethylpyrazine and guaiacol, a total of 0.1 to 1 ppm of amino acids, 5.0 to 70.0 mg / 100 ml of potassium, 3.0 to 50.0 mg / 100 ml of sodium, 1.0 to 15.0 mg / 100 ml of phosphorus, 0.05 to 0.8 mg / 100 ml of calcium, 0.1 to 5.0 mg / 100 ml of magnesium, 0.05 to 2.0 g / 100 g of carbohydrates, and 0.01 g / 100 g to 1.5 g / 100 g of protein, and the mass contents of sugars glucose, fructose, sucrose, maltose, lactose, starch and caffeine are all below the detection limit. And, all of the following examples and comparative examples have been confirmed to have such component compositions.

[0037] (clarity) The black bean tea beverage of the present invention is preferably a clear beverage. From this perspective, the T% of the black bean tea beverage of the present invention is preferably 60% or more, more preferably 70% or more, and even more preferably 75% or more.

[0038] (pH) The pH of the black bean tea beverage of the present invention is preferably 6.20 to 6.60, from the viewpoint of providing a sense of concentration when drunk, and more preferably 6.25 or more or 6.55 or less, and even more preferably 6.30 or more or 6.50 or less.

[0039] <Method of producing black bean tea beverage of the present invention> The black bean tea beverage of the present invention can be produced, for example, by extracting roasted black beans with an aqueous solvent to obtain an extract (extraction step), filtering the obtained extract (filtration step), adding an isoflavone preparation if necessary (addition step), adding or blending appropriate ingredients to prepare a blend (blending step), sterilizing the blend, and filling the blend into a container (sterilization and filling step) to produce a bottled black bean tea beverage. However, the production method is not limited to this. For example, the order of the addition step and the filtration step may be reversed, and the addition step and the blending step may not be separate steps. Each step will be described below.

[0040] According to the method for producing a black bean tea beverage of the present invention, the flavor of the packaged black bean tea beverage can be improved, and in particular the astringent taste can be suppressed. Therefore, the method for producing a packaged black bean tea beverage can be used as a method for suppressing the astringent taste of packaged black bean tea beverages. That is, as an example of an embodiment of the present invention, a method for suppressing the astringent taste of a packaged black bean tea beverage containing at least tannin, isoflavones, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine is a method for suppressing the astringent taste of a packaged black bean tea beverage containing at least tannin, isoflavones, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine, characterized by adjusting the ratio of the mass of isoflavones to the mass of tannins (isoflavones / tannins) to 0.5 to 6.0, and adjusting the total mass of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine to 260 ppb to 1500 ppb.

[0041] (Roasted black beans) Roasted black beans can be obtained by roasting raw black beans. Examples of raw black beans include Tanba Kuro, Hikari Kuro, Tokachikuro, Kurosengoku, Iwaikuro, Tamadaikoku, Shinano Kuro, Ganbane, Murasakizukin, Wachi Kuro, Sakushu Kuro, Kurodamaru, and Kuromarukun.

[0042] The roasting treatment can be carried out by any method known to those skilled in the art, such as hot air roasting, sand roasting, far-infrared roasting, open-air roasting, rotary drum roasting, medium roasting, microwave roasting, superheated steam roasting, charcoal roasting, etc. These methods can also be combined.

[0043] By adjusting the roasting conditions, it is possible to adjust, for example, the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine, the mass content of guaiacol, and the like, as described above.

[0044] Therefore, taking these points into consideration, one example of roasting conditions is that, with regard to the roasting temperature, from the viewpoint of imparting a roasted aroma to the raw black beans, the product temperature is preferably 130° C. or higher, more preferably 140° C. or higher, even more preferably 150° C. or higher, and even more preferably 160° C. or higher. On the other hand, from the viewpoint of preventing the outer skins of the raw black beans from burning, the product temperature is preferably 200° C. or lower, more preferably 190° C. or lower, even more preferably 180° C. or lower, and even more preferably 170° C. or lower.

[0045] Regarding the roasting time, in order to roast the raw black beans to the core, it is preferable to maintain the above temperature for 600 seconds or more, more preferably 700 seconds or more, even more preferably 800 seconds or more, and even more preferably 900 seconds or more. On the other hand, it is preferable to maintain the above temperature for 1500 seconds or less, even more preferably 1400 seconds or less, even more preferably 1300 seconds or less, and even more preferably 1200 seconds or less. However, the conditions are not limited to these.

[0046] The roasted raw material black beans are crushed as needed. By grinding the raw black beans, the elution properties are improved, and more of the components in the raw black beans can be eluted. The pulverization method used in this case may be a roll grinder type, a flat cutter type, a conical cutter type, or the like.

[0047] (extraction process) The roasted black beans are preferably extracted with an aqueous solvent.

[0048] The method for extracting roasted black beans is not particularly limited, and any known method may be used, such as immersion extraction, drip extraction, or showering extraction. Examples of water-soluble solvents that can be used for extraction include pure water, tap water, distilled water, desalted water, alkaline ionized water, lake water, deep sea water, ion-exchanged water, deoxygenated water, natural water, hydrogen water, and water containing water-soluble organic compounds (e.g., alcohols) or inorganic salts.

[0049] By adjusting the extraction conditions, it is possible to adjust the tannin content, the 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine content, the guaiacol content, the soluble solids content (Brix), and the like, as described above. Therefore, taking this into consideration, the amount of water-soluble solvent used during extraction is preferably 5 times (mass) or more of the amount of roasted black beans, since the raw black beans are soaked in the solvent, and more preferably 8 times (mass) or more, more preferably 10 times (mass) or more, and even more preferably 13 times (mass) or more. On the other hand, from the viewpoint of the concentration of black bean tea, it is preferably 50 times (mass) or less, more preferably 45 times (mass) or less, more preferably 40 times (mass) or less, and even more preferably 35 times (mass) or less. Note that the extraction temperature refers to the temperature of the extraction solvent. The temperature for extracting roasted black beans is preferably 30° C. or higher, more preferably 50° C. or higher, even more preferably 70° C. or higher, and even more preferably 80° C. or higher, from the viewpoint of allowing the flavor of the raw black beans to be adequately felt. Note that the extraction temperature refers to the temperature of the extraction solvent. The extraction time of the roasted black beans is preferably 10 minutes or more, more preferably 20 minutes or more, more preferably 30 minutes or more, and even more preferably 50 minutes or more, from the viewpoint of dissolving the components derived from the raw black beans. On the other hand, from the viewpoint of the stability of the properties of the packaged beverage, it is preferably 120 minutes or less, more preferably 110 minutes or less, more preferably 100 minutes or less, and even more preferably 90 minutes or less. Stirring may be performed as necessary.

[0050] (filtration process) The black bean extract obtained by the above extraction is preferably immediately cooled and then filtered. Rapid cooling can further promote the precipitation or suspension of substances that cause turbidity, which not only more reliably prevents the occurrence of suspension or precipitation in the final black bean tea beverage, but also shortens the production time. The method of rapid cooling is not particularly limited, but in consideration of cooling efficiency, it is preferable to rapidly cool the material to about 5 to 30°C using, for example, a plate-type heat exchanger. As the filtration method, it is preferable to use a combination of centrifugal filtration, shape-selective filtration, adsorption filtration, etc., and shape-selective filtration is particularly effective.

[0051] By this type of filtration, it is possible to filter out isoflavones, which are sparingly soluble in water and are contained in the components extracted from roasted black beans. Furthermore, even if the order of the addition process and the filtration process is reversed, water-soluble isoflavones can remain in the beverage after the filtration process, and at least the main component of the isoflavones contained in the black bean tea beverage of the present invention can be water-soluble isoflavones.

[0052] (addition process) If necessary, it is preferable to add a water-soluble isoflavone preparation. Since some of the isoflavones extracted from roasted black beans are poorly soluble in water, in order to improve the clarity (transparency) of the black bean tea beverage of the present invention, it is preferable to filter out the poorly water-soluble isoflavones and add a water-soluble isoflavone preparation containing water-soluble isoflavones. However, it is difficult to adjust the mass content of water-soluble isoflavones in the black bean tea beverage of the present invention to 5.0 mg / 100 ml or more simply by extracting roasted black beans. Therefore, in order to adjust the mass content of water-soluble isoflavones in the black bean tea beverage of the present invention to 5.0 mg / 100 ml or more, it is necessary to add an isoflavone preparation or polyphenol preparation containing water-soluble isoflavones.

[0053] Water-soluble isoflavone preparations are commercially available, and isoflavones can be prepared, for example, by extracting soybeans, particularly soybean germs, with an organic solvent.

[0054] The amount of the water-soluble isoflavone preparation to be added is not particularly limited, but it is preferable to adjust it so that it falls within the above-mentioned ratio of isoflavones to tannins.

[0055] (Mixing process) The filtrate obtained in the above filtration step is diluted as necessary, and additives such as minerals, antioxidants such as ascorbic acid and sodium ascorbate, flavorings, pH adjusters such as sodium bicarbonate, emulsifiers, preservatives, sweeteners, coloring agents, thickening stabilizers, seasonings, and strengtheners are blended, either singly or in combination, as necessary. In addition, roasted black beans or soybean germs with different roasting conditions, or multiple types of extracts (filtrates) with different extraction conditions may be mixed and used, or a concentrate may be produced through a concentration process, and the concentrate may be used as is, or may be granulated by spray drying or the like.

[0056] (sterilization / filling process) The beverage obtained in the preparation process is pasteurized before or after being filled into containers. Examples of containers to be filled include glass bottles, molded containers mainly made of polyethylene terephthalate (so-called PET bottles), plastic containers such as multi-layer molded containers, paper containers, and metal containers.

[0057] When a plastic container is used as the container, the oxygen transmission rate (cc / Day / 500 mL bottle) of the container at 25°C and 55% RH is preferably 0.01 to 0.1, more preferably 0.015 or more or 0.08 or less, and even more preferably 0.02 or more or 0.06 or less.

[0058] When filling a container with the black bean tea beverage, it is preferable to fill it at room temperature, and it is also preferable to fill it with nitrogen.

[0059] Sterilization can be carried out at any stage of the manufacturing process. The sterilization conditions can be selected so that they provide the same effect as those specified in the Food Sanitation Act. For example, when a heat-resistant container is used, retort sterilization can be performed. When a non-heat-resistant container is used, the containerized black bean tea beverage can be produced by, for example, sterilizing the black bean tea beverage at high temperature for a short time using a plate-type heat exchanger or the like, cooling it to a predetermined temperature, and filling it while heating, or by aseptically filling it at a low temperature, for example, 10 to 50°C.

[0060] <Explanation of terms> In this specification, when the expression "X to Y" (X and Y are any numbers) is used, unless otherwise specified, it means "X or more and Y or less," as well as "preferably larger than X" or "preferably smaller than Y." Furthermore, when it is expressed as "X or more" (X is any number) or "Y or less" (Y is any number), it also includes the intention that "it is preferable that it is greater than X" or "it is preferable that it is less than Y." [Example]

[0061] The present invention will now be described in further detail with reference to the following examples and comparative examples.

[0062] <Black bean tea drink A> 150 kg of black beans (Hikarikuro (produced in Hokkaido)) were placed in a Fuji Royal far-infrared batch roaster (Fuji Coffee Machine Co., Ltd.), roasted at a product temperature of 200°C for 1500 seconds, and then immediately cooled to obtain roasted black beans. 30g of these roasted black beans were placed in a stainless steel drip extraction container (inner diameter 150mm x height 150mm, volume approximately 3120cm 3 The contents were poured into a container (bottle) so that the height was uniform, and 2 L of 90°C ion-exchanged water was poured in. After holding for 10 minutes, the cock was opened and the contents were drained to obtain an extract. The extraction container was equipped with a cock that could drain the contents and an 80-mesh wire screen for filtering the contents. The discharged extract was cooled to 25°C, filtered through a stainless steel mesh (235 mesh), and then filtered through a flannel to obtain a filtrate. After cooling, the filtrate was centrifuged (continuous centrifuge SA-1, manufactured by Westfalia) for specific gravity separation, and then filtered by shape separation using a cartridge filter (10 μm) to obtain black bean tea beverage A.

[0063] <Black bean tea drink B> In the production method of the above black bean tea beverage A, black bean tea beverage B was obtained in the same manner as black bean tea beverage A, except that the product temperature of the black beans was 110°C for 1500 seconds, the amount of roasted black beans added during extraction was 1000g, and the holding time was changed to 90 minutes.

[0064] <Black bean tea drink C> In the production method of the above black bean tea beverage A, black bean tea beverage C was obtained in the same manner as black bean tea beverage A, except that the product temperature of the black beans was 120°C for 1500 seconds, the amount of roasted black beans added during extraction was 30g, and the holding time was changed to 9 minutes.

[0065] <Black bean tea drink D> In the production method of the above black bean tea beverage A, black bean tea beverage D was obtained in the same manner as black bean tea beverage A, except that the product temperature of the black beans was changed to 250°C x 1500 seconds, the amount of roasted black beans added during extraction was changed to 1000g, and the holding time was changed to 90 minutes.

[0066] Vitamin C and baking soda were added to each of the black bean tea beverages A to D above to adjust the pH to 6.4, and then pure water was added to make up to 5 L. The beverages were then sterilized using UHT and filled into PET bottles to produce the packaged black bean tea beverages. The analytical values ​​for each beverage are shown in Table 1.

[0067] [Table 1]

[0068] <Examples 1 to 6 and Comparative Examples 1 to 4> The above black bean tea beverages A to D were mixed to achieve the mass ratios shown in Table 2, and a water-soluble isoflavone preparation derived from soybean germ (tannin content: less than the lower limit of quantification (lower limit of quantification 3.75 g / 100 g), water-soluble isoflavone content: 11.62 g / 100 g) was added to achieve the isoflavone content mass shown in Table 3. Vitamin C and baking soda were then added to adjust the pH to 6.4, and pure water was added to bring the total volume to 5 L. The mixture was sterilized using UHT and filled into PET bottles to obtain a bottled black bean tea beverage (sample).

[0069] [Table 2]

[0070] <Beverage component analysis> The black bean tea drinks A to D and the packaged black bean tea drink (sample) were analyzed and measured using the following methods, and the values ​​of each component and each physical property were calculated.

[0071] (Isoflavones) High performance liquid chromatograph (HPLC) was operated under the following conditions, and quantitative determination was carried out by the calibration curve method. Daidzin, glycitin, and genistin were used as standard substances, and calibration curves were prepared based on their respective peak areas. Daidzin, malonyldaidzin, acetyldaidzin, and daidzein were quantified as daidzin, glycitin, malonylglycitin, acetylgenistin, and glycitein using the calibration curve of daidzin, genistin, malonylgenistin, acetylgenistin, and genistein using the calibration curve of glycitin, and genistein, malonylgenistin, acetylgenistin, and genistein, respectively. The quantified values ​​were multiplied by the molecular weight ratio of each compound to the standard substance used to prepare the calibration curve to obtain the mass content of each compound. The mass content of daidzin, glycitin, genistin, malonyldaidzin, malonylglycitin, malonylgenistin, acetyldaidzin, acetylglycitin, acetylgenistin, daidzein, glycitein, and genistein was then added together to obtain the mass content of isoflavones.

[0072] Column: Kanto Chemical Mightysil RP-18 φ4.6 x 250 mm Column temperature: 35℃ Mobile phase: 15% acetonitrile solution Acetonitrile:water:acetic acid = 15:85:0.1 (W / W) 35% acetonitrile solution Acetonitrile:water:acetic acid = 35:65:0.1 (W / W) Elution conditions: Linear gradient of acetonitrile concentration from 15 to 35% in 50 minutes Do the following. Flow rate: 1mL / min Injection volume: 10μL Detection: Waters "Ultraviolet detector UV254nm"

[0073] (tannins) Tannins were determined according to the ferrous tartrate method by Anan et al. (Reports of Tea Research 71 (1990) 43-74). The pH of the phosphate buffer used for the measurement was changed to 5.5.

[0074] (Dimethylpyrazine, guaiacol) The total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine and the mass content of guaiacol were measured using a gas chromatograph mass spectrometer (GC-MS) under the following conditions. The total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine is expressed as "three types of pyrazines" in the table.

[0075] Each sample was diluted appropriately, and 10 mL of sample, 3 g of sodium chloride, and 10 ppm guaiacol-3,4,5,6-d4 (internal standard) were added to a 20 mL vial. The sample was then extracted. The extraction procedure was performed using a solid-phase microextraction (SPME) fiber (Sigma-Aldrich, 50 / 30 μm DVB / CAR / PDMS, 1 cm) at 60°C for 30 min. The resulting sample was subjected to gas chromatography-mass spectrometry under the following conditions. The mass content of each aroma component was determined by the standard addition method using the ratio of the peak area of ​​each component to the peak area of ​​the internal standard.

[0076] Gas chromatograph conditions: Equipment used: Agilent 5973N (Agilent Technologies) Injection: Splitless mode Inlet temperature: 240℃ Column: DB-WAX 60m x 0.25mm x 0.25μm Carrier: Helium Flow rate: 0.8mL / min Oven temperature: 40℃~5℃ / min~240℃ Mass spectrometry conditions: Equipment used: Agilent 5973N (Agilent Technologies) Ionization method: Electron ionization (EI) method The following ions were used to quantify each component. Guaiacol-3,4,5,6-d4 m / z 128 2,5 dimethylpyrazine m / z 108 2,3 dimethylpyrazine m / z 108 2,6 dimethylpyrazine m / z 108 Guaiacol m / z 124

[0077] (Soluble solid content (Brix)) Brix was measured using a measuring device manufactured by Atago Co., Ltd. (digital differential densitometer RX-DD7α-Tea).

[0078] (T%) The container-packed black bean tea beverages (samples) obtained in the Examples and Comparative Examples were shaken well, and 4.0 mL was sampled in a standard glass cell. The transmittance (660 nm) was measured using a Shimadzu UV-1800 ultraviolet-visible spectrophotometer, and the result was expressed as clarity (T%).

[0079] <Sensory evaluation test> Seven panelists engaged in the manufacture of tea beverages were selected to evaluate the packaged black bean tea beverages (samples) obtained in the Examples and Comparative Examples, and tests 1 to 5 were conducted based on the following evaluation methods. After discussion, the most common evaluation was adopted for each test, and the results of the discussion were also used for the overall evaluation. Test 1 was carried out for Examples 1 to 6 and Comparative Examples 1 to 4, and for Examples 1 to 6 which showed good results in Test 1, further Tests 2 to 5 were carried out.

[0080] As a control for each test, the following preparation was used. Positive control for Test 1: Black bean tea made by steeping a 300g packet of commercially available whole black bean tea in 200ml of boiling water for 3 minutes. Negative control for Test 1: Isoflavone solution prepared by dissolving 20 mg of a commercially available formulation (Fujiflavone P10) in 100 ml of hot water at 60°C. Positive control for Tests 2 and 3: Black bean tea heated to 50°C (122°F) Positive control for Test 4: Black bean tea cooled to 5°C (10°F) Negative control for Test 5: A guaiacol solution prepared by adding guaiacol to hot water at 50°C to make a concentration of 100 ppm.

[0081] First, the panelists were asked to drink the control in advance and discuss the flavor of the control among themselves, so that they would have a common understanding of the control's "astringency," "burnt aroma," "taste," "lingering sweetness," "persistence of sweet roasted aroma," and "bitterness."

[0082] The definitions of the evaluation items in each test are as follows: Astringent taste: A bitter taste-like sensation specific to isoflavone preparations that tightens the tongue when drinking a diluted aqueous solution containing only the isoflavone preparation used in this study. Burnt aroma: A bitter, charcoal-like smoky aroma mixed with a sour aroma that is felt when the coffee is over-roasted. Oil float: The thickness of oil present on the liquid surface. Taste: The rich sweetness and aroma of black bean drink. Lingering sweetness: The sweetness that lingers after drinking black bean drink. Persistence of sweet roasted aroma: The length of time that the sweet roasted aroma that feels like sweetness lasts after drinking. Bitterness: A bitter aftertaste that can be felt when drinking warm.

[0083] Sensory evaluation of test 1 The beverage was drunk at room temperature and evaluated for astringency and burnt aroma, and after storing at room temperature for 30 days, the beverage was evaluated for oiliness and taste.

[0084] (Astringent taste and burnt aroma when drunk at room temperature) 3: No astringent taste or burnt smell (same as the positive control). 2: There is a slight astringent taste or a slight burnt smell, but it is within the acceptable range. 1: A strong astringent taste (same as the negative control) or a strong burnt smell.

[0085] (Oil floating and taste) 3: The oil float is less than 1.5 mm and the taste is strong (same as the positive control) 2: The oil float is 1.5 mm or more but less than 2.0 mm, or the taste is weak (slightly weaker than the positive control) 1: Oil float is 2.0 mm or more, or the taste is barely detectable (the taste of the positive control is not detectable)

[0086] ● Sensory evaluation of test 2 The drink was heated to 60°C and then drunk, and the astringent taste was evaluated.

[0087] (Astringent taste when heated) 3: Almost no astringent taste when heated and drunk (almost no astringent taste when drinking the negative control) 2: A slight astringent taste is felt when drinking warm (weaker than the negative control) 1: Astringent taste felt when heated and drunk (same as negative control)

[0088] ● Sensory evaluation of test 3 The beverage was heated to 60°C and consumed, and the aftertaste of sweetness was evaluated.

[0089] (Lingering sweetness when heated) 3: When heated and drunk, a sweet aftertaste is felt (same as the positive control) 2: When drinking warm, the sweetness is a little weak (it disappears after 2 seconds of putting it in your mouth) 1: When drinking warm, there is no lingering sweetness.

[0090] ● Sensory evaluation of test 4 The beverages were cooled to 5°C and consumed to evaluate the persistence of the sweet roasted aroma.

[0091] (Persistence of sweet roasted aroma when drinking chilled) 3: Sweet roasted aroma persists when drinking chilled (same as positive control) 2: When drunk cold, the sweet roasted aroma remains slightly lingering (lasts for 2 seconds after swallowing) 1: The sweet roasted aroma hardly lasts when drinking chilled

[0092] ● Sensory evaluation of test 5 The beverage was heated to 60°C and drunk, and the bitterness was evaluated.

[0093] (Bitterness when heated) 3: Almost no bitterness when heated 2: A slight bitterness is felt when drinking heated 1: Bitterness felt when heated and drunk (same as negative control)

[0094] [Table 3]

[0095] (Consideration) The results of Test 1 showed that the astringent taste and burnt aroma were suppressed for Examples 1 to 5. Furthermore, oil floating could be suppressed while still retaining a pleasant taste. Therefore, it was found that by adjusting the isoflavone content / tannin content ratio to 0.5 to 6 and adjusting the total content of the aroma components 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, and 2,6-dimethylpyrazine (also referred to as "three pyrazines") to 260 ppb to 1500 ppb, it is possible to provide a black bean tea beverage with no astringent taste and reduced oil floating. Furthermore, by filtering out the poorly water-soluble isoflavones contained in the components extracted from roasted black beans and leaving the water-soluble isoflavones contained in the isoflavone preparation, such as soybean germ-derived isoflavones, in the beverage, the clarity (transparency) of the beverage could be improved. From this, it was found that it is preferable that at least the main component of the isoflavones contained in the black bean tea beverage of the present invention is water-soluble isoflavones, such as soybean germ-derived isoflavones.

[0096] The results of Test 2 showed that an astringent taste was felt when heated in Example 6. This indicates that the astringent taste of black bean tea beverages can be suppressed even when heated and consumed by adjusting the isoflavone content to 20.0 mg / 100 ml or less.

[0097] The results of Test 3, as seen in Example 5, showed that no lingering sweetness was felt when drinking heated. Therefore, it was found that by adjusting the tannin content to 15.0 mg / 100 ml or less, it is possible to provide a black bean tea beverage that has a lingering sweetness even when heated.

[0098] The results of Test 4, as seen in Example 5, showed that the sweet roasted aroma did not persist when the beverage was cooled. Therefore, it was found that by adjusting the ratio of three pyrazines / Bx to 500 or more, it is possible to provide a black bean tea beverage that retains the sweet roasted aroma when the beverage is cooled.

[0099] The results of Test 5 showed that Example 2 tasted bitter when heated and drunk. This indicates that the bitterness of the black bean tea beverage when heated and drunk can be reduced by adjusting the aroma component guaiacol to 118 ppb or less.

Claims

1. A packaged black bean tea beverage containing at least tannins, isoflavones, 2,5 dimethylpyrazine, 2,3 dimethylpyrazine, and 2,6 dimethylpyrazine, It contains water-soluble isoflavones as the main component of isoflavones, The ratio of the mass of isoflavones contained to the mass of tannins contained (isoflavones / tannins) is 0.5 to 6.0, and A packaged black bean tea beverage having a total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine of 260 ppb to 1500 ppb.

2. 2. The packaged black bean tea beverage according to claim 1, wherein the mass content of the isoflavones is 20.0 mg / 100 ml or less.

3. 3. The packaged black bean tea beverage according to claim 1, wherein the mass content of the tannins is 15.0 mg / 100 ml or less.

4. The packaged black bean tea beverage according to claim 1 or 2, wherein the ratio of the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine to the soluble solids content (Brix) of the packaged black bean tea beverage (dimethylpyrazine total / Brix) is 500 or more. Packaged black bean tea beverage.

5. 3. The packaged black bean tea beverage according to claim 1, wherein the guaiacol content is 118 ppb or less.

6. A method for suppressing an astringent taste in a packaged black bean tea beverage containing at least tannins, isoflavones, 2,5-dimethylpyrazine, 2,3-dimethylpyrazine, and 2,6-dimethylpyrazine, comprising: The ratio of the mass of isoflavones to the mass of tannins (isoflavones / tannins) is adjusted to 0.5 to 6.0, and A method for suppressing the astringent taste of a packaged black bean tea beverage, comprising adjusting the total mass content of 2,5 dimethylpyrazine, 2,3 dimethylpyrazine and 2,6 dimethylpyrazine to 260 ppb to 1500 ppb.

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