Dried kudzu flower powder and foods containing dried kudzu flower powder

Abstract

The present invention pertains to a food that contains a dried kudzu flower powder and has a moisture content of 8 wt% or less. In this food, the ratio of the fraction passing through a 2 mm-mesh screen is preferably 20 wt% or more. The food according to the present invention has a good taste and smell.

Description

[Technical Field]

[0001] The present invention relates to dried powder of kudzu flower and a food product containing the same. [Background technology]

[0002] Kudzu is a creeping plant of the legume family, and kudzu starch extracted from its roots has long been used as an ingredient in Japanese sweets. Its roots and flowers, called kudzu root and kudzu flower, respectively, have long been used in China as antipyretics, antidiarrheals, and treatments for alcoholism.

[0003] As for kudzu flowers, kudzu flower extracts extracted with a solvent (kudzu flower extract) are widely used. For example, a food composition for preventing or improving menopausal symptoms, which contains kudzu flower extract and one or more extracts selected from the group consisting of bee husk and dried orange peel, has been proposed (Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-197519 Summary of the Invention [Problem to be solved by the invention]

[0005] However, kudzu flower extract requires an extraction process, which increases the number of manufacturing steps and makes the manufacturing process complicated. In addition, kudzu flower extract has a unique flavor (taste and aroma), making it unsuitable for eating as is or for incorporating into a wide range of foods.

[0006] An object of the present invention is to provide dried kudzu flower powder that has a good flavor and is suitable as a food, and a food containing the same. [Means for solving the problem]

[0007] In the course of their research into foods using kudzu flowers, the present inventors focused on the use of dried kudzu flower powder to improve the unique flavor of kudzu flower extract. Specifically, they discovered that dried kudzu flower powder has a more favorable flavor as a food product than kudzu flower extract. As a result of further research into this dried kudzu flower powder, they discovered that adjusting the moisture content of the dried kudzu flower powder to a predetermined amount can preserve its favorable flavor for a long period of time, leading to the completion of the present invention.

[0008] That is, the present invention is as follows. [1] Dried kudzu flower powder characterized by having a moisture content of 8% by weight or less. [2] The dried kudzu flower powder described in [1], in which the proportion of the fraction passing through a sieve with 2 mm mesh is 20% by weight or more. [3] The dried kudzu flower powder according to [1] or [2], characterized in that it is for food use. [4] A food product comprising the dried kudzu flower powder according to any one of [1] to [3]. [5] A food product containing dried kudzu flower powder and having a moisture content of 8% by weight or less. [6] The food product according to [4] or [5], characterized in that it is for reducing body fat. [7] The food product according to [4] or [5], characterized in that it is used to improve obesity. [8] The food product according to [4] or [5], characterized in that it is used to improve blood cholesterol. [Effects of the Invention]

[0009] The dried powder of kudzu flower of the present invention and foods containing the same have good taste and aroma. DETAILED DESCRIPTION OF THE INVENTION

[0010] The dried powder of kudzu flower of the present invention and the food containing the same are characterized by having a moisture content of 8% by weight or less.

[0011] The dried powder of kudzu flowers has a better taste and aroma than the extract of kudzu flowers, and is therefore suitable as a food product. Furthermore, since the water content is 8% by weight or less, the following effects are achieved. (1) It is suitable for use as food because it retains its good taste and aroma for a long period of time, can be stored for a long period of time, and has a sufficient shelf life. (2) When the dried powder of kudzu flowers is ingested as is, it has a pleasant flavor, making it suitable for use as a food (powdered food, tablet, etc.) that is ingested as is (without being suspended in water, etc.). (3) Because it disperses easily in water (hot water), it is also suitable for use as a powdered drink (instant drink). (4) Since the amount of tectorigenins (useful components of kudzu flowers) dissolved in water (hot water) is large, it is also suitable for use as a tea bag beverage.

[0012] The moisture content of the kudzu flower dried powder of the present invention and foods containing it is preferably 3% by weight or more. A moisture content of 3% by weight or more tends to increase cell-activating activity. In the food of the present invention, the moisture content of the entire food and the moisture content of the blended kudzu flower dried powder itself are considered to be the same.

[0013] Kudzu is a perennial climbing plant of the genus Pueraria in the family Fabaceae, and kudzu flowers are used in the present invention. The kudzu flowers used in the present invention may be harvested at any stage, from bud to fully opened flower, or a mixture of flowers harvested at each stage may be used. The type of kudzu is not particularly limited, but examples include Pueraria thomsonii, Pueraria lobata, and Pueraria thunbergiana. From the standpoints of availability and various effects, Pueraria thomsonii is preferred.

[0014] The dried kudzu flower powder of the present invention is a powder obtained by drying and pulverizing collected kudzu flowers, and does not include dried powder of extract or squeezed juice. Specifically, for example, kudzu flowers collected are washed and dried to obtain dried kudzu flowers, which are then pulverized to obtain dried kudzu flower powder.

[0015] Regarding the particle size distribution (by weight) of the kudzu flower dried powder of the present invention, from the viewpoints of flavor, dispersibility, and elution of tectorigenins and the like, the proportion of the fraction passing through a sieve with a mesh size of 2 mm, preferably 1.18 mm, is preferably 5 wt% or more, more preferably 10 wt% or more, even more preferably 20 wt% or more, even more preferably 50 wt% or more, even more preferably 70 wt% or more, and particularly preferably 80 wt% or more. Furthermore, this fraction is preferably a fraction that does not pass through a sieve with a mesh size of 0.25 mm, preferably 0.15 mm. For example, this fraction may be a fraction that passes through a sieve with a mesh size of 2 mm but not 0.25 mm, or a fraction that passes through a sieve with a mesh size of 1.18 mm but not 0.15 mm.

[0016] The lower limit of the proportion of the fraction that passes through a 2 mm opening but does not pass through a 0.25 mm opening is not particularly limited, but from the viewpoint of flavor, dispersibility, or elution of tectorigenins, etc., it is preferably 1.5 wt% or more, more preferably 5 wt% or more, even more preferably 10 wt% or more, even more preferably 20 wt% or more, even more preferably 50 wt% or more, and particularly preferably 65 wt% or more. The upper limit of the proportion of the fraction that passes through a 2 mm opening but does not pass through a 0.25 mm opening is not particularly limited, but from the viewpoint of flavor, dispersibility, or elution of tectorigenins, etc., it is preferably 99 wt% or less, more preferably 98 wt% or less, even more preferably 95 wt% or less, even more preferably 94 wt% or less, even more preferably 93 wt% or less, and particularly preferably 92 wt% or less.

[0017] The lower limit of the proportion of the fraction that passes through a 1.18 mm opening but does not pass through a 0.15 mm opening is not particularly limited, but from the viewpoint of flavor, dispersibility, or elution of tectorigenins, etc., it is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 20% by weight or more, even more preferably 40% by weight or more, even more preferably 60% by weight or more, and particularly preferably 70% by weight or more. The upper limit of the proportion of the fraction that passes through a 1.18 mm opening but does not pass through a 0.15 mm opening is not particularly limited, but from the viewpoint of flavor, dispersibility, or elution of tectorigenins, etc., it is preferably 99.5% by weight or less, more preferably 99% by weight or less, even more preferably 98% by weight or less, even more preferably 97% by weight or less, even more preferably 96% by weight or less, and particularly preferably 95% by weight or less.

[0018] The upper limit of the particle size (median size (by weight)) of the kudzu flower dried powder of the present invention is preferably 2 mm or less, more preferably 1.65 mm or less, and particularly preferably 1 mm or less, from the viewpoints of flavor, dispersibility, and elution of tectorigenins, etc. Preferably, it is 0.15 to 1.65 mm, more preferably 0.18 to 1.65 mm, even more preferably 0.25 to 1.00 mm, even more preferably 0.30 to 0.90 mm, even more preferably 0.35 to 0.80 mm, and particularly preferably 0.38 to 0.70 mm. The particle size distribution and median diameter can be measured using, for example, a robot sifter manufactured by Seishin Enterprise Co., Ltd.

[0019] Traditionally, tea bag beverages filled with plant powders, such as flower tea, characterized by their aroma, have often used relatively large powders. In other words, they have been used without being finely crushed, because the aroma quickly deteriorates during storage after being crushed into fine particles. In contrast, dried kudzu flower powder, with a moisture content of 8% by weight or less, does not lose its aroma quickly even when crushed to the fine particle size mentioned above, and the aroma can be maintained even in a fine powder.

[0020] Furthermore, the loose bulk density of the kudzu flower dried powder of the present invention is preferably 0.2 g / mL or more from the viewpoint of ease of filling when producing powdered foods such as powdered drinks and tea bag drinks.

[0021] Furthermore, the compressibility of the kudzu flower dried powder of the present invention is preferably 11% or more from the viewpoint of ease of filling when producing powdered foods such as powdered drinks and tea bag drinks containing the kudzu flower dried powder. The compressibility is a value calculated from the difference between the hardened bulk density and the loose bulk density.

[0022] The loose bulk density was determined by filling a container of a specified capacity with dried kudzu flower powder, leveling off the top, and measuring the weight. The hardened bulk density was determined by filling a container of a specified capacity with dried kudzu flower powder, tapping it 180 times, and then leveling off the top and measuring the weight.

[0023] The specific surface area (helium adsorption BET method) of the dried powder of kudzu flower in the present invention is 0.3 m from the viewpoints of flavor, dispersibility, and elution of tectorigenins, etc. 2 / g or more, and 0.4m 2 / g or more is more preferable, and 0.5m 2 / g or more is more preferable, and 0.6m 2 / g or more is more preferable, and 0.65m 2 / g or more, and more preferably 0.7m 2 It is particularly preferable that the saturation coefficient is 1 / g or more.

[0024] The lower limit of the angle of repose of the kudzu flower dried powder of the present invention is preferably 31 degrees or more, more preferably 44 degrees or more, even more preferably 45 degrees or more, even more preferably 46 degrees or more, and particularly preferably 47 degrees or more. The upper limit of the angle of repose of the kudzu flower dried powder of the present invention is preferably 65 degrees or less, more preferably 55 degrees or less, even more preferably 53 degrees or less, even more preferably 52 degrees or less, even more preferably 51 degrees or less, and particularly preferably 50 degrees or less. The angle of repose can be measured, for example, using a Multitester MT1000 manufactured by Seishin Enterprise Co., Ltd.

[0025] The content of kudzu flower dried powder in the food of the present invention is not particularly limited, but is generally, for example, 0.01 to 100% by weight, preferably 1 to 95% by weight, more preferably 3 to 90% by weight, and even more preferably 5 to 85% by weight, based on the total weight of the food. Furthermore, when used as a powdered beverage or tea bag beverage, the content of kudzu flower dried powder is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 20% by weight or more, even more preferably 50% by weight or more, even more preferably 80% by weight or more, and particularly preferably 90% by weight or more. Furthermore, when kudzu flower dried powder is used as a tea bag beverage, the tea bag beverage may contain only kudzu flower dried powder.

[0026] Since dried kudzu flower powder contains isoflavones such as tectorigenins, it is effective in reducing body fat. The food of the present invention can be used as a general food, as well as a functional food whose efficacy has been recognized by a designated organization, such as a food for specified health uses, a food with nutrient function claims, or a food with functional claims, so-called health foods. The content of tectorigenins in dried kudzu flower powder is, for example, preferably 1 to 25% by weight, more preferably 3 to 20% by weight, and even more preferably 5 to 15% by weight. Tectorigenins refer to one or more compounds selected from tectorigenin, tectoridin, and tectorigenin 7-O-xylosylglucoside (TGXG). When tectorigenins contain two or more of the above compounds, the content of tectorigenins refers to the total amount of these compounds.

[0027] That is, the food of the present invention can be used as an obesity-reducing food (diet food), such as a food for reducing body fat. Such an obesity-reducing food is not particularly limited as long as it contains kudzu flower dried powder with a moisture content of 8% by weight or less and can be distinguished from other products in that it is used to reduce obesity. For example, the scope of the present invention includes products that display on the product itself, packaging, instructions, or promotional materials (advertising media) that the product has a function related to obesity reduction, such as a body fat reduction function. Note that the obesity-reducing food of the present invention is not limited to products that display kudzu flower as an active ingredient on the product packaging, etc. For example, products that do not specify the active ingredient may also be used. Furthermore, even general foods that are manufactured and sold with a suggested use are included in the scope of the obesity-reducing food of the present invention.

[0028] Specifically, examples of so-called health foods include those that claim to "suppress fat absorption," "for those concerned about weight," "help those who are slightly obese to lose weight and body fat," "help those who are slightly obese to reduce visceral fat (belly fat) and BMI," "for those concerned about visceral fat," "reduce (improve) high BMI," "for those concerned about high BMI," "make it easier to burn fat," and "supports a healthy figure."

[0029] The food of the present invention can also be used as a food for improving blood cholesterol. Such a food for improving blood cholesterol is not particularly limited as long as it contains kudzu flower dried powder with a moisture content of 8% by weight or less and is distinguishable from other products in that it is used to improve blood cholesterol, such as lowering cholesterol or inhibiting cholesterol elevation. For example, the scope of the present invention includes products that display a cholesterol-improving function on the product itself, packaging, instructions, or promotional materials (advertising media) of the present invention. The blood cholesterol-improving food of the present invention is not limited to products that display kudzu flower as an active ingredient on the product packaging, etc. For example, products without a specified active ingredient may also be used. Furthermore, even general foods that are manufactured and sold with a suggested use are included in the scope of the blood cholesterol-improving food of the present invention.

[0030] Specifically, examples of so-called health foods include those that claim to "suppress the rise in cholesterol," "for those concerned about cholesterol," "lower (improve) high cholesterol," and "lower total cholesterol and bad (LDL) cholesterol."

[0031] The intake amount of the health food of the present invention is not particularly limited. However, in order to further enhance its effects, in the case of a food in which kudzu flower dried powder is ingested as is, the intake amount of kudzu flower dried powder per adult is preferably 0.1 mg or more, more preferably 10 mg or more, and even more preferably 50 mg or more per day. The upper limit is, for example, 5000 mg, preferably 3000 mg, and more preferably 2000 mg. In the case of a food in which kudzu flower dried powder is extracted with hot water or the like, such as a tea bag drink, the intake amount of kudzu flower dried powder (amount contained in a tea bag) per adult is preferably 0.01 mg or more, more preferably 1 mg or more, and even more preferably 100 mg or more per day. The upper limit is, for example, 5000 mg, preferably 3000 mg, and more preferably 2000 mg.

[0032] The health food of the present invention may be appropriately designed so that the daily intake is the above-mentioned intake amount, and may be taken in one dose or in multiple doses. For example, it may be taken 1 to 4 times per day, as long as the total amount is the above-mentioned intake amount. The health food of the present invention may be packaged as a daily amount in a single container or divided into, for example, 2 to 3 containers so that the daily intake is the above-mentioned intake amount.

[0033] Examples of the form of the food of the present invention include tablets, capsules, powders, granules, particles, rods, plates, blocks, solids, rounds, caplets, chewable tablets, sticks, jellies, etc. Among these, in the case of health foods, tablets, capsules, powders, granules, rounds, and chewable tablets are preferred.

[0034] When in powder or granular form, it can be used as a powdered drink or tea bag drink. In the case of tea bag drinks, the dried kudzu flower powder of the present invention has a high elution amount of tectorigenins (useful components of kudzu flower) in water (hot water), so it can effectively achieve body fat reduction effects, etc.

[0035] The food product of the present invention can be produced by known methods, optionally adding ingredients other than the dried kudzu flower powder. Examples of other ingredients include water-soluble vitamins (vitamins B1, B2, B3, B5, B6, B12, B13, B15, B17, biotin, choline, folic acid, inositol, PABA, vitamin C, and vitamin P) and oil-soluble vitamins (vitamins A, D, E, and K); minerals (magnesium, phosphorus, zinc, and iron); sulfur-containing compounds (e.g., found in garlic); flavanoids (e.g., hesperidin and quercetin); proteins (e.g., collagen); peptides; amino acids; animal fats and oils; vegetable fats and oils; and ground animal or plant extracts.

[0036] In particular, when the food product of the present invention is used as a powdered beverage or tea bag beverage, other plant materials besides the dried kudzu flower powder may be blended. Examples of plant materials include tea leaves such as green tea leaves and black tea leaves, catnip, hyssop, milk thistle, yarrow, and chicory. Examples of these plant materials include dried powders obtained by drying and grinding harvested plants. Among these plant materials, using tea leaves, especially green tea leaves, in combination with the product provides a more favorable flavor. [Example]

[0037] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples, and the present invention can take various forms as long as the object of the present invention can be achieved.

[0038] 1. Sensory test 1-1. Comparison by moisture content <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The drying time for the hot air drying was adjusted to achieve a predetermined moisture content. The dried kudzu flowers (dried kudzu flowers) were milled under controlled conditions to achieve a median diameter (by weight) of approximately 0.4 mm, a fraction passing through a 2 mm sieve with a mesh size of 90% or more, and a fraction passing through a 2 mm sieve but not a 0.25 mm sieve with a mesh size of 70-81%. The kudzu flower dried powders of Examples 1-4 and Comparative Example 1 were produced with similar median diameters and particle size distributions. After production, the powders were stored at room temperature (25°C) for at least one month before testing. The moisture contents of Examples 1-4 and Comparative Example 1 are shown in Table 1.

[0039] [Table 1]

[0040] <Sensory testing> For Examples 1 to 4 and Comparative Example 1, sensory tests were carried out by the methods described below to evaluate flavor and the like.

[0041] (1) Eight subjects were given 1 g of dried kudzu flower powder from the test cup, and the taste intensity and other aspects were evaluated. The evaluation was scored according to the following criteria in comparison with Comparative Example 1. The results are shown in Table 2.

[0042] 3 points very good 2 points Good 1 point: Rather good 0 points No change -1 point: Rather bad -2 points Bad -3 points Very bad

[0043] [Table 2]

[0044] (2) A tea bag filled with dried kudzu flower powder was extracted with hot water and given to six subjects for evaluation. Specifically, 1.7 g of dried kudzu flower powder was first packed into a tea bag. 300 mL of hot water was poured into the tea bag, which was then left to stand for 3 minutes, after which the tea bag was shaken up and down approximately 10 times and then removed. Approximately 30 mL of the extract was transferred to a test cup, and the sweetness and richness upon ingestion, as well as stickiness and discomfort in the mouth after ingestion were evaluated. The evaluation criteria were the same as those in (1) above. The results are shown in Table 3.

[0045] [Table 3]

[0046] Tables 2 and 3 show that kudzu flower dried powder with excellent flavor and other properties can be obtained by adjusting the moisture content of the kudzu flower dried powder to 8% by weight or less (Examples 1 to 4). In particular, kudzu flower dried powder with a moisture content of 3 to 8% by weight exhibited significantly superior flavor and sweetness and other properties (Examples 2 to 4). However, when kudzu flower extract was used, the flavor and taste were worse than those of kudzu flower dried powder, even though the moisture content was the same.

[0047] 1-2. Comparison by median diameter (weight basis) <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The hot air drying was carried out by adjusting the drying time so that the specified moisture content was obtained. The dried kudzu flowers (dried kudzu flowers) were subjected to a pulverization process under adjusted pulverization conditions, and fractionated through a sieve to produce dried kudzu flower powders of Examples 5 to 8, each with a moisture content of 3.2% by weight and different median diameters. The median diameters of Examples 5 to 8 are shown in Table 4.

[0048] [Table 4]

[0049] <Sensory testing> Five subjects evaluated the sweetness of the aroma by placing their noses close to a test cup containing 1 g of dried kudzu flower powder. They then took a pinch of dried kudzu flower powder from the cup and ingested it, and evaluated the aftertaste. After ingestion, the aroma remaining in the mouth was evaluated. The evaluation criteria were the same as in 1-1(1) above. The results are shown in Table 5.

[0050] [Table 5]

[0051] As shown in Table 5, the kudzu flower dried powders with a median diameter of 0.18 mm or more (Examples 6 to 8) had a superior aftertaste when ingested compared to the kudzu flower dried powder with a median diameter of 0.17 mm (Example 5). In particular, the kudzu flower dried powders with a median diameter of 0.18 to 1.65 mm (Examples 6 and 7) also had a superior sweet aroma before ingestion and a superior aroma after ingestion.

[0052] 1-3.Comparison by specific surface area <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The hot air drying was performed by adjusting the drying time so that the desired moisture content was achieved. The dried kudzu flowers (dried kudzu flowers) were then pulverized under adjusted pulverization conditions and fractionated through a sieve to produce dried kudzu flower powders of Examples 9 and 10, each with a moisture content of 3.2% by weight and different specific surface areas. The specific surface areas of Examples 9 and 10 are shown in Table 6.

[0053] [Table 6]

[0054] <Sensory testing> Five subjects evaluated the sweetness of the aroma by placing their noses close to a test cup containing 1 g of dried kudzu flower powder. They then took a pinch of dried kudzu flower powder from the cup and ingested it, evaluating its flavor, intensity, and aftertaste. After ingestion, the aroma remaining in the mouth was evaluated. The evaluation criteria were the same as in 1-1(1) above. The results are shown in Table 7.

[0055] [Table 7]

[0056] As shown in Table 7, the specific surface area is 0.5 m 2 / g (Example 9) 2 The dried powder of kudzu flower containing 100mg of kudzu or more (Example 10) had an excellent sweet aroma before ingestion, flavor, strength of taste and aftertaste upon ingestion, and aroma after ingestion.

[0057] 1-4. Comparison by particle size distribution <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The hot air drying was performed by adjusting the drying time so that the desired moisture content was achieved. The dried kudzu flowers (dried kudzu flowers) were subjected to a pulverization process under adjusted pulverization conditions, and fractionated through a sieve to produce the kudzu flower dried powders of Examples 11 to 13, each with a moisture content of 3.2% by weight and different particle size distributions. The particle size distributions and median diameters of Examples 11 to 13 are shown in Table 8.

[0058] [Table 8]

[0059] <Sensory testing> Five subjects evaluated the sweetness of the aroma by placing their noses close to a test cup containing 1 g of dried kudzu flower powder. They then picked up a sample of dried kudzu flower powder from the cup, evaluated the color intensity, and then ingested it. After ingestion, the aroma remaining in the mouth was evaluated. The evaluation criteria were the same as in 1-1(1) above. The results are shown in Table 9.

[0060] [Table 9]

[0061] As shown in Table 9, dried kudzu flower powders (Examples 12 and 13) in which the proportion of the fraction that passed through a 2 mm mesh size but did not pass through a 0.25 mm mesh size was 20% by weight or more had a sweeter aroma before ingestion, a deeper color upon ingestion, and a better aroma after ingestion than powders in which the proportion of this fraction was less than 20% by weight (Example 11).

[0062] 1-5. Comparison by angle of repose <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The hot air drying was carried out by adjusting the drying time so that the specified moisture content was obtained. The dried kudzu flowers (dried kudzu flowers) were subjected to a pulverization process under adjusted pulverization conditions, and fractionated through a sieve to produce the kudzu flower dried powders of Examples 14 to 17, each with a moisture content of 3.2% by weight and different angles of repose. The angles of repose for Examples 14 to 17 are shown in Table 10.

[0063] [Table 10]

[0064] <Sensory testing> Five subjects evaluated the sweetness of the aroma by placing their noses close to a test cup containing 1 g of dried kudzu flower powder. They then picked up a sample of dried kudzu flower powder from the cup, evaluated the color intensity, and then ingested it. After ingestion, the aroma remaining in the mouth was evaluated. The evaluation criteria were the same as in 1-1(1) above. The results are shown in Table 11.

[0065] [Table 11]

[0066] As shown in Table 11, the kudzu flower dried powders with a repose angle of 53 degrees or less (Examples 15 to 17) had a stronger color intensity upon ingestion than the kudzu flower dried powder with a repose angle of 54 degrees (Example 14). Furthermore, the kudzu flower dried powders with a repose angle of 45 degrees or more (Examples 16 and 17) also had a sweeter aroma before ingestion and a stronger aroma after ingestion than the kudzu flower dried powder with a repose angle of 44 degrees (Example 15).

[0067] 2.Dissolution test 2-1. Comparison by moisture content (1) <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The drying time for the hot air drying was adjusted to achieve the desired moisture content. The dried kudzu flowers (dried kudzu flowers) were milled under controlled conditions to achieve a median diameter of approximately 0.4 mm, a fraction passing through a 2 mm mesh size of 90% or more, and a fraction passing through a 2 mm mesh size but not a 0.25 mm mesh size of 70-81%. The dried kudzu flower powders of Examples 18 and 19 and Comparative Example 2 were produced with similar median diameters and particle size distributions. After production, the powders were stored at room temperature (25°C) for at least one month before testing. The moisture contents of Examples 18 and 19 and Comparative Example 2 are shown in Table 12.

[0068] [Table 12]

[0069] <Dissolution test> 100 mg of kudzu flower dried powder was weighed into a 1.5 mL tube, 1 mL of pure water was added, and the mixture was vortexed for 30 seconds. After centrifugation, the supernatant was measured for absorbance at 465 nm. The absorbance of pure water was measured as a blank. The blank value was subtracted, and the values ​​for Examples 18 and 19 were evaluated as absorbances, with Comparative Example 2 set at 100. Higher absorbances indicate higher dissolution rates of the components contained in the kudzu flower dried powder. The results are shown in Table 13.

[0070] [Table 13]

[0071] Compared to the kudzu flower dried powder with a moisture content of over 8% by weight (Comparative Example 2), the kudzu flower dried powder with a moisture content of 8% by weight or less (Examples 18 and 19) had higher absorbance values ​​and showed excellent dissolution properties of the components contained in the kudzu flower dried powder.

[0072] 2-2. Comparison by moisture content (2) <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The drying time for the hot air drying was adjusted to achieve the desired moisture content. The dried kudzu flowers (dried kudzu flowers) were milled under controlled conditions to achieve a median diameter of approximately 0.4 mm, a fraction passing through a 2 mm mesh size of 90% or more, and a fraction passing through a 2 mm mesh size but not a 0.25 mm mesh size of 70-81%. The kudzu flower dried powders of Examples 20 and 21, with similar median diameters and particle size distributions, were produced. After production, the powders were stored at room temperature (25°C) for at least one month before testing. The moisture contents of Examples 20 and 21 are shown in Table 14.

[0073] [Table 14]

[0074] <Dissolution test> 100 mg of dried kudzu flower powder was weighed into a 1.5 mL tube, 1 mL of pure water was added, and the mixture was vortexed for 30 seconds. After centrifugation, the supernatant was measured for absorbance at 465 nm. The absorbance of pure water was measured as a blank. The blank value was subtracted, and the value of Example 21 was set to 100, and the value of Example 20 was used as the absorbance for evaluation. The results are shown in Table 15.

[0075] [Table 15]

[0076] Compared to the dried kudzu flower powder with a moisture content of less than 3% by weight (Example 21), the dried kudzu flower powder with a moisture content of 3% by weight or more (Example 20) had a higher absorbance value and was superior in terms of the elution of the components contained in the dried kudzu flower powder.

[0077] 2-3. Comparison by median diameter <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The hot air drying was performed by adjusting the drying time so that the specified moisture content was obtained. The dried kudzu flowers (dried kudzu flowers) were subjected to a pulverization process under adjusted pulverization conditions, and fractionated through a sieve to produce the kudzu flower dried powders of Examples 22 to 26, each with a moisture content of 3.2% by weight and different median diameters. The median diameters of Examples 22 to 26 are shown in Table 16. [Table 16]

[0078] <Dissolution test> 100 mg of dried kudzu flower powder was weighed into a 1.5 mL tube, 1 mL of pure water was added, and the mixture was vortexed for 30 seconds. After centrifugation, the supernatant was measured for absorbance at 465 nm. The absorbance of pure water was measured as a blank. The blank value was subtracted, and the values ​​for Examples 22 to 25 were evaluated as absorbance, with Example 26 set to 100. The results are shown in Table 17.

[0079] [Table 17]

[0080] Compared to the kudzu flower dried powder with a median diameter of 1.67 mm (Example 26), the kudzu flower dried powders with a median diameter of 1.65 mm or less (Examples 22 to 25) had higher absorbance values ​​and were superior in dissolving the components contained in the kudzu flower dried powder.

[0081] 3. Analysis of tectorigenins The amount of tectorigenins (total amount of tectorigenin, tectoridin, and tectorigenin 7-O-xylosylglucoside) contained in the dried kudzu flower powder was analyzed by the method described below. The content of tectorigenins in the dried kudzu flower powders of Examples 1 to 26 was 5 to 15 wt%.

[0082] Tectorigenins were measured by refluxing dried kudzu flower powder with 50% methanol and then analyzing by HPLC. Specifically, the analytical column was a YMC-Pack ODS AM12S05-2546WT (φ4.6 × 250 mm) manufactured by YMC Co., Ltd., and the guard column was a YMC-Pack ODS AM12S05-G304CC (φ4.0 × 23 mm) or YMC-Pack ODS AM12S05-0204GC (φ4.0 × 20 mm) manufactured by YMC Co., Ltd. The mobile phase was a mixture of acetonitrile / water / acetic acid (mobile phase A volume ratio = 15:85:0.1, mobile phase B volume ratio = 35:65:0.1), with the column temperature set at 35°C and the flow rate set at 1.0 mL / min. The gradient conditions are as shown in Table 18.

[0083] [Table 18]

[0084] 4. Comparison with Kudzu Flower Extract <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried in the sun and by hot air drying to a moisture content of 5%. The dried kudzu flowers were crushed, and the dried kudzu flower powder with a median diameter of approximately 0.4 mm was used for the test. Meanwhile, the harvested kudzu flowers were extracted with hot water, filtered, and then dried with hot air to a moisture content of 5%.

[0085] <Sensory testing> The above-mentioned kudzu flower dried powder and kudzu flower extract powder were subjected to sensory tests using the following two methods.

[0086] (1) Four subjects were given 1 g of dried kudzu flower powder from the test cup, and the sweetness of the aroma and other characteristics were evaluated before ingestion. The evaluation was scored according to the following criteria in comparison with kudzu flower extract powder. The results are shown in Table 19.

[0087] 3 points very good 2 points Good 1 point: Rather good 0 points No change -1 point: Rather bad -2 points Bad -3 points Very bad

[0088] [Table 19]

[0089] As shown in Table 19, the dried kudzu flower powder was superior to the kudzu flower extract powder in all the evaluated items.

[0090] (2) A tea bag filled with dried kudzu flower powder was extracted with hot water and given to four subjects for evaluation. Specifically, 1.7 g of dried kudzu flower powder was first packed into a tea bag. 300 mL of hot water was poured into the tea bag, which was then left to stand for 3 minutes, after which the tea bag was shaken up and down approximately 10 times and then removed. The extract was transferred to a test cup, and the sweetness and richness upon ingestion, as well as stickiness and discomfort in the mouth after ingestion were evaluated. The evaluation criteria were the same as those in (1) above. The results are shown in Table 20.

[0091] [Table 20]

[0092] As shown in Table 20, the dried kudzu flower powder was superior to the kudzu flower extract powder in all the evaluated items.

[0093] 5. Dissolution test and cell activation test 5-1. Comparison by moisture content <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The drying time for the hot air drying was adjusted to achieve the desired moisture content. The dried kudzu flowers (dried kudzu flowers) were milled under controlled conditions to achieve a median diameter (weight basis) of approximately 0.4 mm, a fraction passing through a 2 mm sieve with a mesh size of 90% or more, and a fraction passing through a 2 mm sieve but not a 0.25 mm sieve with a mesh size of approximately 70-80%. The dried kudzu flower powders of the Examples and Comparative Examples were produced with similar median diameters and particle size distributions. After production, the powders were stored at room temperature (25°C) for at least one month before testing. The moisture contents of Examples 27-30 and Comparative Example 3 are shown in Table 21.

[0094] [Table 21]

[0095] <Dissolution test> The dissolution test was carried out by the following method. (1) Approximately 200 mg of dried kudzu flower powder was weighed into a 5 mL sampling tube. (2) Serum-free DMEM was added to the solution to a concentration of 100 mg / mL, and the mixture was stirred for 2 minutes using a tube mixer. (3) The mixture was centrifuged at 15,000×g for 2 minutes at room temperature, and the supernatant was collected in a 1.5 mL sampling tube. (4) To remove fine powder, the mixture was further centrifuged (room temperature, 15,000×g for 2 minutes) and the supernatant was collected. (5) The supernatant was diluted 100-fold with serum-free DMEM, and 100 μL of each was dispensed onto an assay plate (UV-Star). The absorbance at 264 nm was measured. In addition, the absorbance of serum-free DMEM alone was measured as a blank, and the absorbance was corrected.

[0096] The results are shown in Table 22. The dissolution rate is shown as a relative value, with the blank-corrected absorbance at 264 nm of Comparative Example 3 taken as 100, and a higher value means higher dissolution rate.

[0097] [Table 22]

[0098] The kudzu flower dried powders of Examples 27 to 30, which had a moisture content of 8% or less, were superior in dissolution properties to the kudzu flower dried powder of Comparative Example 3, which had a moisture content of more than 8%.

[0099] <Cell activation test> A cell activation test was carried out by the following method. (1) Caco-2 cells cultured in 10% FBS-1% NEAA-DMEM medium were seeded onto a 96-well plate and pre-cultured in a CO2 incubator at 37°C. (2) After pre-culture, the cells were washed once with serum-free DMEM. (3) The sample (100 mg / mL) eluted in (4) of the above <Elution Test> was diluted with serum-free DMEM to 1.25 mg / mL and added to each well. As a control, serum-free DMEM medium was added. (4) After adding the sample, the cells were cultured in a CO2 incubator at 37°C for 6 hours. (5) After washing once with serum-free DMEM medium, 150 μL / well of Cell Counting Kit-8 diluted 30-fold with serum-free DMEM was added. Additionally, a blank well containing no cells was also added in the same manner. (6) After allowing the color to develop appropriately in a CO2 incubator at 37°C, the absorbance at 450 nm was measured. The cell activation activity was calculated by correcting for the blank absorbance.

[0100] The results are shown in Table 23. The cell-activating activity is shown as a relative value with the control value taken as 100, and a higher value means a higher cell-activating activity.

[0101] [Table 23]

[0102] In all examples, the cell-activating activity values ​​were higher than the control. Examples 28 to 30, in which the water content was 3% or more and 8% or less, had higher cell-activating activity than Example 27, in which the water content was less than 3%.

[0103] 5-2. Comparison by median diameter <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried by sun drying and hot air drying. The hot air drying was performed by adjusting the drying time so that the desired moisture content was achieved. The dried kudzu flowers (dried kudzu flowers) were subjected to a pulverization process under adjusted pulverization conditions, and fractionated through a sieve to produce dried kudzu flower powders of Examples 31 to 34, each with a moisture content of 3.2% by weight and different median diameters. The median diameters of Examples 31 to 34 are shown in Table 24.

[0104] [Table 24]

[0105] <Dissolution test> The test was conducted in the same manner as the dissolution test in "5-1. Comparison by water content" above. In this test, approximately 150 mg of dried kudzu flower powder was weighed in (1), and in (2), it was stirred for 10 minutes in a tube mixer.

[0106] The results are shown in Table 25. The dissolution rate is expressed as a relative value, with the blank-corrected absorbance at 264 nm of Example 34 taken as 100, and a higher value means higher dissolution rate.

[0107] [Table 25]

[0108] Compared with Example 34, which had a median diameter of more than 1.65 mm, the kudzu flower dried powders of Examples 31 to 33, which had a median diameter of 1.65 mm or less, all had excellent dissolution properties.

[0109] <Cell activation test> The test was conducted in the same manner as the dissolution test in "5-1. Comparison by water content" above. In this test, the dissolved sample was diluted to 3 mg / mL in (2) and then cultured for 8 hours in (4).

[0110] The results are shown in Table 26. The cell-activating activity is shown as a relative value with the control value taken as 100, and a higher value means a higher cell-activating activity.

[0111] [Table 26]

[0112] In all Examples, the numerical values ​​of the cell activating activity were higher than the control. Examples 32 to 34, in which the median diameter was 0.18 mm or more, had higher cell activating activity than Example 31, in which the median diameter was less than 0.17 mm.

[0113] 6. Confirmation of changes in blood cholesterol levels after intake of dried kudzu flower powder <Preparation of dried kudzu flower powder> The harvested kudzu flowers were dried in the sun and by hot air drying. The drying time for the hot air drying was adjusted to achieve the desired moisture content. The dried kudzu flowers (dried kudzu flowers) were then crushed under adjusted crushing conditions and fractionated through a sieve to produce dried kudzu flower powders with the same moisture content (approximately 5% by weight) but different median diameters (1.75 mm, 0.45 mm).

[0114] <Animal testing> Male C57BL / 6J mice were acclimatized and then divided into groups based on body weight. Each group was allowed to freely consume the diet shown in Table 27 below for 36 days. On the final day of the study, the mice were dissected, and blood was collected from the inferior vena cava to obtain serum. Total blood cholesterol levels were measured using a commercially available kit (product name "Cholesterol E-Test Wako"; Fujifilm Wako Pure Chemical Industries, Ltd.). The results are shown in Table 28.

[0115] [Table 27]

[0116] [Table 28]

[0117] Ingestion of dried powder of kudzu flowers reduced total cholesterol levels in the blood. A particularly large reduction was observed in Example 36, which has a smaller particle size.

[0118] 7. Sensory test using a combination of dried kudzu flower powder and green tea <Sensory testing> Tea bags filled with dried kudzu flower powder and dried green tea powder of predetermined moisture content and median diameter were extracted with hot water, and the extract was administered to five subjects for evaluation. Specifically, 0.45 g of dried kudzu flower powder and 1.25 g of dried green tea powder were first packed into a tea bag. 150 mL of hot water was poured into the tea bag, and the tea bag was left to stand for 3 minutes. After stirring the tea bag up and down approximately 10 times, the tea bag was removed. The palatability upon ingestion was evaluated. For Examples 38 to 40 and Comparative Example 4, the composition ratio of dried kudzu flower powder and dried green tea powder in the tea bag, as well as the median diameter and moisture content of the dried kudzu flower powder used in each Example and Comparative Example, are shown in Table 29.

[0119] [Table 29]

[0120] The evaluation was performed by assigning points according to the following criteria in comparison with Comparative Example 4. The results are shown in Table 30.

[0121] 3 points very good 2 points Good 1 point: Rather good 0 points No change -1 point: Rather bad -2 points Bad -3 points Very bad

[0122] [Table 30]

[0123] As shown in Table 30, good results were obtained when kudzu flower dried powder and green tea dried powder were used in combination with the kudzu flower dried powder of the present invention, which had a moisture content of 8% or less. Furthermore, the combination of kudzu flower dried powder and green tea dried powder with a median diameter of 0.18 to 1.65 mm (Examples 38 and 39) produced even better results.

[0124] [Formulation Example 1] Tea bags (2 g per bag) containing dried kudzu flower powder were produced. The dried kudzu flower powder had a moisture content of 4% by weight and a median diameter (by weight) of 1 mm. The beverage made using the resulting tea bags had a good taste and aroma. Furthermore, consuming this beverage once a day provided excellent effects such as reducing body fat.

[0125] [Composition Example 2] Tea bags (2 g per bag) containing dried kudzu flower powder (70 wt%) and dried catnip powder (30 wt%) were produced. The dried kudzu flower powder had a moisture content of 4 wt% and a median diameter (by weight) of 1 mm. The beverage made using the resulting tea bags had a good taste and aroma. Furthermore, consuming this beverage once a day provided excellent effects such as reducing body fat.

[0126] [Composition Example 3] Tea bags (2 g per bag) containing dried kudzu flower powder (50 wt%) and dried hyssop powder (50 wt%) were produced. The dried kudzu flower powder had a moisture content of 6 wt% and a median diameter (by weight) of 1.4 mm. The beverage made using the resulting tea bags had a good taste and aroma. Furthermore, consuming this beverage once a day provided excellent effects such as reducing body fat.

[0127] [Composition Example 4] A food product (2 g) containing dried kudzu flower powder (70% by weight) and dried catnip powder (30% by weight) was produced. The dried kudzu flower powder had a moisture content of 4% by weight and a median diameter (by weight) of 1 mm. The resulting food product had a good taste and aroma. Furthermore, taking this food product once a day provided excellent effects such as reducing body fat. [Industrial Applicability]

[0128] The food of the present invention can be used as a general food as well as a health food, and is therefore highly useful industrially.

Claims

[Claim 1] A dried powder of kudzu flowers characterized by having a moisture content of 8% by weight or less and a median diameter of 0.18 to 1.65 mm.

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