JP5812657B2 - Bitter or astringent taste inhibitor for beverages or foods - Google Patents

Description

The present invention relates to a bitter or astringent beverage or a food bitter or astringent inhibitor, a method of using the same, a processed tea leaf product with reduced bitterness or astringency, and a beverage containing the processed tea leaf product or The present invention relates to a food and a method for producing the processed tea leaf product.
Specifically, the present invention relates to a bitterness and astringency inhibitor comprising casein phosphopeptide or sericin, and relates to a method for suppressing the bitterness or astringency of a beverage or food by adding casein phosphopeptide or sericin to the beverage or food.
The present invention also relates to a processed tea leaf product to which casein phosphopeptide or sericin is added, a beverage or food containing the processed tea leaf product, and a method for producing the processed tea leaf product.

  Bitterness and astringency of beverages and foods are important elements of palatability as characteristics of the beverages and foods. On the other hand, too bitterness and astringency of flavors are factors that impair the flavor of beverages and foods. In recent years, plant-derived functional ingredients have attracted attention for the purpose of promoting health. However, many of these ingredients have strong bitterness and astringency, and beverages and foods containing sufficient amounts have bitterness and astringency. Becomes stronger and the palatability is reduced. Therefore, it is required to suppress the bitterness and astringency of beverages and foods.

  In particular, tea contains various functional ingredients including catechins, and is attracting attention as a health functional drink or food. However, the intake of catechins is limited due to strong astringency and bitterness.

  As a method for reducing the bitterness and astringency of tea beverages, methods for removing catechins with a resin such as insoluble polyvinylpolypyrrolidone (PVPP) have been reported (Patent Documents 1, 2, and 3). However, since these methods use expensive resins, they are costly and require complicated operations. Moreover, since the catechins are removed, the health function expected of the processed tea leaf product is reduced.

  Further, as a method for suppressing the bitterness and astringency of the tea extract, proteins such as protamine (patent document 4), milk protein (patent document 5), soybean protein (patent document 6), and pea protein (patent document 7) are added. A method is disclosed. However, the effects of these proteins were not always sufficient. Furthermore, since these proteins have a strong flavor, when added to a processed tea leaf product, the flavor of the beverage or food is affected. In addition, these proteins have poor solubility, and when added to beverages, turbidity and precipitation occur.

  Furthermore, a method for suppressing the bitterness of a tea composition using cyclodextrin has been reported (Patent Document 8). In order to suppress bitterness by addition of cyclodextrin, it is necessary to add a large amount of cyclodextrin, and when a large amount of cyclodextrin is added, there arises a problem that a taste of cyclodextrin occurs.

Japanese Patent Laid-Open No. 9-220055 JP 2000-41577 A Japanese Patent Application Laid-Open No. 2004-159597 JP-A-5-328935 JP 2000-323913 A JP 2004-73196 A JP 2006-180830 A JP-A-3-16848

The object of the present invention is to suppress the bitterness and astringency of beverages and foods.
In particular, the inhibitory effect on bitterness and astringency caused by tea catechins is high, and even if a sufficient amount of catechins and theaflavins are added to the beverage or food, the flavor of the beverage or food itself is not impaired, It is intended to provide a simple and low-cost method for producing a processed tea leaf product and a beverage or food containing the processed tea leaf product and the processed tea leaf product that do not impair the appearance of the processed tea leaf.

  The inventors of the present invention selectively bind a specific protein component to catechins and theaflavins in beverages or foods, particularly to strongly bind to gallate catechins that have a strong bitterness and astringency. As a result, the present inventors have found that beverages and foods in which bitterness and astringency are easily suppressed can be provided without affecting the flavor and appearance, and the present invention has been completed.

That is, the present invention is as follows.
(1) A bitter or astringent taste inhibitor for beverages or foods, characterized by containing casein phosphopeptide or sericin as an active ingredient, and (2) adding a casein phosphopeptide or sericin. Catechins contained in beverages or foods, characterized by adding casein phosphopeptides or sericin to beverages or foods containing catechins Concentration reduction method

Furthermore, the present invention is as follows.
(4) Casein phosphopeptide or sericin is added to one type selected from tea leaf extract, suspension, granulated product, pulverized product, and dry powder of the extract or suspension. Processed tea leaves (5) Drinks or foods characterized by containing the processed tea leaves (6) Processed tea leaves characterized by adding casein phosphopeptide or sericin to tea leaf extract or suspension (7) A method for producing a processed tea leaf product comprising adding powdered casein phosphopeptide or sericin to powdered tea leaf or solid tea leaf extract and granulating

  Moreover, the present invention is the above (4) to (7), wherein the amount of casein phosphopeptide or sericin added is 0.01 to 100 parts by mass with respect to 1 part by mass of the solid content derived from tea leaves; Are black tea, green tea, and oolong tea.

ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to suppress the bitterness or astringency which a drink or food has, without affecting the flavor of a drink or food. In particular, the effect of suppressing the bitterness and astringency of catechins and theaflavins in processed tea leaves is high without impairing the flavor of tea.
Therefore, the amount of the tea leaf processed product added to the beverage or food can be increased without reducing the flavor inherent to the beverage or food.
Furthermore, even tea beverages containing normal concentrations of catechins and theaflavins can be drunk in large quantities because bitterness and astringency are reduced.
Furthermore, since the tea beverage produced in this way does not cause turbidity, the appearance of the product is excellent and it contributes to the quality improvement of the product.

The present invention is described in detail below.
(1) Bitter / Astringent Inhibitor In the present invention, protein-based casein phosphopeptide (CPP) or sericin is used as an active ingredient for suppressing a bitter / astringent taste.
Casein phosphopeptide (abbreviated as CPP) is a peptide obtained by degrading milk protein casein with trypsin, and is disclosed in, for example, JP-A-58-170440 and JP-A-59-159793. Can be obtained according to the method.

Japanese Patent Laid-Open No. 59-159793 introduces the following production method.
"Example 1: 10 g of lactate casein (New Zealand) was dissolved in water to give a 10% solution (pH 8.0). To this solution was added 0.01% swine crystal trypsin (manufactured by Novo) to the substrate to pH 7 The mixture was reacted at 0.5 to 8.5 for 6 hours at 50 ° C. To this reaction solution, ferric chloride was added to a concentration of 10 mM, and the mixture was stirred and allowed to stand overnight at 5 ° C. The precipitated CPP Fractions were collected by centrifugation, washed with a small amount of water and then vacuum dried to give 1.2 g of CPP fraction, CPP purity was 92%, N / P = 8.9.
Such casein phosphopeptides may be commercially available products such as “CPP-III” manufactured by Meiji Food Materia Co., Ltd.

  On the other hand, sericin is a protein contained in silk fiber, and is treated with hot water to elute the silkworm or raw silk into the water, which is disclosed in International Publication No. 2002-086133, etc. Can be obtained according to the method.

The following manufacturing method is introduced in the pamphlet of International Publication No. 2002-086133.
“Production Example 1: 1 kg of cocoon (made by Bombyx mori) was hydrothermally treated in 50 L of 0.2% sodium carbonate aqueous solution (pH 11-12) at 95 ° C. for 2 hours, and sericin The resulting sericin hydrolyzate extract was filtered using a filter having an average pore size of 0.2 μm to remove aggregates, and then the filtrate was desalted with a reverse osmosis membrane to obtain a sericin concentration of 0. Then, a 2% colorless and transparent aqueous solution of sericin hydrolyzate was obtained, which was then concentrated using an evaporator until the sericin concentration was about 2%, and then freeze-dried to obtain a purity of 90%. Thus, 100 g of a sericin hydrolyzate (polypeptide A) powder having an average molecular weight of 20,000 was obtained.

As sericin, a commercially available product such as “Hi-sericin P-103” manufactured by Kashiro Sangyo Co., Ltd. may be used.
The sericin may be one having a molecular weight degraded to about 1,000 to 100,000 by an enzyme such as trypsin.
When the sericin has a low molecular weight, the effect of reducing bitterness and astringency is weak, whereas when it has a high molecular weight, the solubility is expected to be poor. Therefore, the molecular weight of sericin in the present invention is preferably 1,000 to 100,000.

  CPP or sericin does not have a characteristic odor like pea protein, soy protein or milk protein, and does not have a strong astringent taste like protamine. Therefore, in order to become familiar with the flavor of beverages or foods, especially tea, when added to beverages or foods, especially tea, their flavors are not impaired.

  Addition of pea protein, soybean protein, milk protein and protamine to beverages, especially tea extract, causes turbidity, but adding CPP or sericin to beverages, especially tea extract, does not cause turbidity. Natural and preferable as a beverage. CPP or sericin has a high inhibitory effect on bitterness or astringency against tea-derived catechins or theaflavins, so that the amount of the tea-containing composition added to beverages or foods can be increased. Physiological activity effect can be enhanced.

In addition to CPP or sericin, antioxidants, salt, fragrances, various esters, sugars, colorants, emulsifiers, preservatives, seasonings, sweeteners, color formers, as long as the bitter taste control effect of the present invention is not impaired. In addition, additives such as a pH adjusting agent may be blended.
In addition, the form of the bitter and astringent taste inhibitor of the present invention is not particularly limited, and examples thereof include an aqueous solution, an emulsion, a powder, a granular material, and a preparation.

The bitter and astringent taste inhibitor of the present invention may be used for food or drink before use in the production process of a beverage or food, used during production, or used in a produced product. It is not particularly limited.
In addition, as described later, a processed tea leaf product containing CPP or sericin can be used for beverages or foods. Also in this case, the use time of the processed tea leaf product is not particularly limited.

(2) Beverages or foods containing bitterness or astringency components Beverages or foods for which bitterness and astringency are to be suppressed in the present invention include beverages and foods in general that have a bitterness or astringency that causes a problem in palatability, Specifically, it is a beverage or food containing polyphenols or alkaloids as plant-derived bitter substances.
For example, black tea, green tea, and oolong tea containing polyphenol component catechins, theaflavins, and thealvidins as bitter substances, and foods containing these tea leaf extracts, concentrates, and tea leaf materials can be mentioned.

Further, coffee containing polyphenol component chlorogenic acid or alkaloid caffeine as a bitter substance, and extracts and concentrates thereof, and foods containing coffee bean raw materials can be mentioned.
Furthermore, cocoa and chocolate made from cocoa beans containing catechins of polyphenol components and the alkaloid theobromine as bitter substances are also included.
In addition, various health teas such as guava tea containing tannin, which is an astringent ingredient, can be mentioned.

(3) Use amount of bitter and astringent taste inhibitor Generally, in the case of protein, when the addition amount increases, the flavor of the protein itself affects the flavor of the beverage or food to which it is added. However, since the unique flavor of CPP or sericin itself is weak, it can be used more than general proteins. However, considering the cost, if the effect can be expected, the addition amount should be low.
Therefore, the amount of the bitter and astringent taste inhibitor of the present invention is generally within the range of 0.001 to 50 parts by mass of the active ingredient CPP or sericin in the inhibitor with respect to 1000 parts by mass of the beverage or food. The amount is preferably 0.01 to 50 parts by mass. If the amount is less than 0.001 part by mass, a sufficient bitter and astringent taste suppressing effect cannot be obtained. On the other hand, if the amount exceeds 50 parts by mass, the cost increases and the cost increases.

Addition of bitter and astringent taste inhibitors to foods and drinks, add bitter and astringent taste inhibitors to the beverage or food solution at the above-mentioned use amount, and immediately after mixing at a temperature condition of 5 to 90 ° C. or for 1 second to 30 minutes. If stirring is continued, the bitterness or astringency component in CPP or sericin and a drink or food will couple | bond together.
Such bonds are due to intermolecular interactions such as hydrophobic bonds, hydrogen bonds, ionic bonds, etc., but the bitterness or astringency components physically contact the sensory organs in the oral cavity by binding to CPP or sericin. It becomes impossible, and as a result, it does not feel bitterness or astringency.

The solution thus obtained can be used as a beverage or food, but a mixture from which moisture has been removed by spray drying, freeze drying, or the like can also be used for powder or solid food.
In the case of a solid food, if it is immersed in a CPP or sericin solution at a temperature of 5 to 90 ° C. for 1 minute to 1 day, the CPP or sericin and the bitter or astringent component in the food are combined.
Alternatively, even when solid CPP or sericin is directly mixed with solid food, when the food is eaten, CPP or sericin is combined with the bitter or astringent component in the food in the oral cavity.

  Moreover, CPP or sericin in the present invention strongly binds to catechins, particularly gallate catechins that are considered to have a strong bitterness and astringency. Therefore, when mixed with a beverage or food, the concentration of free catechins contained in the beverage or food can be reduced. When the concentration of free catechins contained in a beverage or food is lowered, it is expected that the bitterness or astringency of the beverage or food is reduced.

(4) Processed Tea Leaf Product The processed tea leaf product of the present invention is a CPP or sericin selected from tea leaf extract, suspension, granulated product, pulverized product, and dry powder of the extract or suspension. Is added.
The tea leaves in the present invention are those obtained by processing leaves and stems of the camellia family Camellia genus, representative examples of which are non-fermented tea such as green tea, semi-fermented tea such as oolong tea, and tea leaves of fermented tea such as black tea. Can be mentioned.

Since CPP and sericin used in the present invention have a relatively weak flavor of the protein itself, even if the concentration is high, there is little influence, but considering the cost, it is better to add a smaller amount.
The blending ratio of CPP or sericin in the processed tea leaf product is generally from 0.01 to 100 parts by mass with respect to 1 part by mass of the tea leaf-derived solid, although it depends on the content of catechins and theaflavins in the tea-derived solids. Yes, preferably 0.1 to 10 parts by mass, and more preferably 0.1 to 3 parts by mass.

  If the blending ratio of CPP or sericin is less than 0.01 parts by mass, the effect of suppressing the bitterness or astringency of tea becomes insufficient, and the effect of suppressing the sufficient bitterness or astringency cannot be obtained. If it exceeds, it will be expensive and expensive.

(5) Manufacturing method of processed tea leaves The extraction method of tea leaves is not particularly limited, but known hot water extraction is preferably used.
Moreover, since the obtained extract has a large amount of water, it may be preferable to concentrate it. The concentration means is not particularly limited, but a conventional method such as reduced pressure concentration, heat concentration, freeze concentration and the like can be selected as appropriate, but reduced pressure concentration or freeze concentration is more preferable because there is little deterioration in flavor due to heating.

  The method for adding CPP or sericin to the tea leaf extract is that the CPP or sericin aqueous solution or suspension is used to prepare a tea leaf extract or tea leaf suspension. Sericin may be added. Further, CPP or sericin may be added after the tea leaf extract or tea leaf suspension is dried to a powder state, and is not particularly limited.

Addition of CPP or sericin to the tea leaf extract or suspension is carried out immediately after mixing at a temperature of 5 to 90 ° C by adding CPP or sericin to the tea leaf extract or suspension in the above-mentioned use amount, or If stirring is continued for 1 second to 30 minutes, CPP or sericin and the tea leaf extract or the bitter or astringent component in the suspension are combined.
Such bonds are due to intermolecular interactions such as hydrophobic bonds, hydrogen bonds, ionic bonds, etc., but the bitter taste component cannot physically contact the sensory organs in the oral cavity by binding to CPP or sericin. As a result, no bitterness or astringency is felt.

  The liquid tea leaf product thus obtained can be used as a beverage or food. In addition, water can be removed from the processed tea leaves in a liquid state by spray drying, freeze drying, or the like. The powdered tea leaf product thus prepared has a low water content and is suitable for storage and transportation.

  Furthermore, the processed tea leaf product can be obtained by granulating after adding the solid or solution or suspension of casein phosphopeptide or sericin to the solid from which water has been removed from the tea leaf extract or suspension by spray drying or freeze drying, etc. It is also possible to manufacture.

It is also possible to produce a processed tea leaf product by mixing a granulated tea leaf with a solid or solution or suspension of CPP or sericin and granulating it.
Even when a processed tea leaf product obtained by granulating solid CPP or sericin with a solid tea leaf extract or a fine powdered tea leaf, when eating food containing the processed tea leaf product, CPP or sericin Bitterness and astringency are reduced by combining bitterness or astringency components in food.

(6) Beverage or food containing processed tea leaves The beverage or food of the present invention is a drink or food characterized by containing the processed tea leaves. Here, the beverage or food is a beverage, powder for beverage, candy, gummi, chewing gum, tablet, tableted confectionery, biscuits, cookies, chocolate, jelly, pudding, bavaroa, cakes, bun, sheep gourd, ice cream, frozen confectionery It is preferable that it is 1 type chosen from these. Since the processed tea leaf product of the present invention has sufficiently suppressed bitterness and astringency, it does not reduce the flavor of the beverage or food itself, so the added amount of the processed tea leaf product can be increased more than before, and catechins Beverages or foods with a high content of tea-derived components such as theaflavins and theaflavins.

If the amount of processed tea leaves is small, a sufficient amount of tea-derived components cannot be ingested. On the other hand, when the added amount of processed tea leaves is increased, the flavor of beverages and foods is affected and the cost is increased.
Therefore, although the amount of tea leaf processed products added to beverages or foods depends on the target food, 0.1 to 30 parts by weight of the tea leaf processed product is added to 100 parts by weight of food in terms of solid content. Is preferred.

  When the processed tea leaf product of the present invention is used for food, it may be used before the production process of the beverage or food, used during production, or used in the product after production. There is no particular limitation.

  The present invention will be described in more detail with reference to the following examples. However, the following examples are used only for illustrative purposes, and the present invention is not limited thereto.

[Measurement Example 1] Solid amount of tea leaf extract Approximately 30 g of sea sand (20-35 mesh: manufactured by Wako Pure Chemical Industries, Ltd.) was added to a porcelain evaporating dish in advance and 1 with a drier set at 105 ° C together with a stirring bar. Dry for more than an hour, allow to cool in a desiccator, and weigh its weight (A) precisely.
About 6 g of tea leaf extract is added here, and its weight (B) is accurately measured and spread evenly with a stir bar. Next, this is dried for 2 hours in a dryer set at 105 ° C., allowed to cool in a desiccator, and then its weight (C) is precisely measured.
The solid content in 100 g of tea extract is calculated by the following formula.
Solid amount = {(C)-(A)} / {(B)-(A)} × 100%

[Measurement Example 2] HPLC analysis of catechins Samples subjected to binding experiments between CPP and bitter or astringent substances were filtered using an ultrafiltration membrane (Amicon Ultra 0.5 (3k) manufactured by Millipore). The filtrate was quantified for the remaining amount of catechins using the following high performance liquid chromatography (HPLC).
The HPLC conditions used in this experimental example are shown below:

Equipment: “Agilent 1100 HPLC system” manufactured by Agilent Technologies, Inc.
Column: “CAPCELL PAK C18MG” manufactured by Shiseido Co., Ltd. (column temperature: 40 ° C.)
Eluent: A. Acetonitrile
B. 10% acetonitrile aqueous solution (pH 2.5 H ₃ PO ₄ )
Gradient condition: 0 minutes → 10 minutes → 25 minutes → 35 minutes A. 0% 0% 15% 100%
B. 100% 100% 85% 0%
Flow rate: 1 mL / min Detection wavelength: 280 nm
The concentration of each component was calculated using a calibration curve prepared with a pure product.

[Test Example 1] Preparation of black tea leaf extract 1000 g of hot water (ion-exchanged water) boiled in 10 g of black tea leaves (produced in India) divided into commercially available tea packs, extracted for 5 minutes, The tea leaf extract was obtained by discarding. When the solid content of this black tea leaf extract was measured according to the method described in Measurement Example 1, it was 0.35% by weight.

[Test Example 2] Preparation of green tea leaf extract 1000 g of hot water (ion-exchanged water) boiled into 10 g of green tea leaves (produced in Shizuoka) divided into commercially available tea packs, extracted for 5 minutes, The green tea leaf extract was obtained by discarding. According to the method described in Measurement Example 1, the solid content of the green tea leaf extract was measured and found to be 0.28% by weight.

[Test Example 3] Preparation of high-concentration green tea leaf extract 1000 g of hot water (ion-exchanged water) boiled in 30 g of green tea leaves (produced in Shizuoka) divided into commercially available tea packs, extracted for 5 minutes, and then green tea together with the tea pack A high concentration green tea leaf extract was obtained by discarding the leaves. According to the method described in Measurement Example 1, the solid content of this highly concentrated green tea leaf extract was measured and found to be 0.73% by weight.

[Example 1] Inhibition effect of CPP and sericin on bitter and astringent taste of black tea In the following tests, CPP is "CPP-III" manufactured by Meiji Food Materia Co., Ltd., and sericin is "Hi Sericin P-103" manufactured by Kashiro Sangyo Co., Ltd. "It was used.

After leaving the tea leaf extract prepared in Test Example 1 to room temperature, CPP or sericin was added to a predetermined concentration and stirred for 1 minute to obtain a processed tea leaf product.
About these processed tea leaf products, sensory evaluation was performed by 8 panelists, and bitterness and astringency were compared. The bitter and astringent taste was evaluated on a 7-point scale from 1 (very weak) to 7 (very strong), with the additive-free tea leaf extract as 5 points.
Table 1 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 1 shows the number of evaluators who performed each evaluation. Further, Table 1 also shows the presence or absence of turbidity occurring in the processed tea leaf product.

[Comparative Example 1] The bitter and astringent taste inhibitory effect of pea protein, soybean protein and sodium casein on the bitter and astringent taste of tea )) Or soybean protein ("Prolina 900" manufactured by Fuji Oil Co., Ltd.) or sodium caseinate ("EM7" manufactured by DMV International) was added to obtain a processed tea leaf product.
About these processed tea leaf products, sensory evaluation was performed by 8 panelists, and bitter and astringent tastes were compared.
The bitter and astringent taste was evaluated on a 7-point scale from 1 (very weak) to 7 (very strong), with 5 black tea extracts added. Table 1 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 1 shows the number of evaluators who performed each evaluation. Further, Table 1 also shows the presence or absence of turbidity occurring in the processed tea leaf product.

As shown in Table 1, not only the bitter and astringent taste of the tea leaf processed product to which CPP or sericin was added was reduced from the additive-free tea leaf extract, but also a bitter and astringent taste reducing effect was reported. The bitter and astringent taste was reduced compared to the case where sodium caseinate was added.
Further, even when CPP or sericin was added to the tea leaf extract, no nuisance such as roughness was felt, and no turbidity occurred. On the other hand, when pea protein, soy protein, and sodium caseinate were added to the black tea extract, a sense of taste including a rough feeling was felt, and turbidity also occurred.
From these things, it became clear that a preferable food and drink can be produced by using the processed tea leaf product of the present invention.

[Example 2] CPP and sericin's bitter and astringent inhibitory effect on bitter and astringent taste of green tea After leaving the green tea leaf extract prepared in Test Example 2 to room temperature, the CPP used in Example 1 to achieve a predetermined concentration or Sericin was added and stirred for 1 minute to obtain a processed green tea leaf product.
These green tea leaf processed products were subjected to sensory evaluation by nine panelists and compared bitterness and astringency.
The bitter and astringent taste was evaluated on a 7-point scale of 1 (very weak) to 7 (very strong), with the additive-free green tea leaf extract as 5 points. Table 2 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 2 shows the number of evaluators who performed each evaluation. Further, Table 2 also shows the presence or absence of turbidity occurring in the processed green tea leaf product.

[Comparative Example 2] Pea protein, soy protein, and sodium casein inhibitory effect on green tea bitterness and astringency Instead of CPP or sericin in Example 2, pea protein or soybean protein or casein used in Comparative Example 1 at a predetermined concentration Sodium green tea leaf processed product was obtained by adding sodium.
These green tea leaf processed products were subjected to sensory evaluation by nine panelists and compared bitterness and astringency.
The bitter and astringent taste was evaluated on a 7-point scale of 1 (very weak) to 7 (very strong), with the additive-free green tea leaf extract as 5 points. Table 2 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 2 shows the number of evaluators who performed each evaluation. Further, Table 2 also shows the presence or absence of turbidity occurring in the processed green tea leaf product.

As shown in Table 2, the bitter and astringent taste of the green tea leaf processed product to which CPP and sericin were added was not only reduced compared to the additive-free green tea leaf extract, but also a bitter and astringent taste-reducing effect was reported. The bitter and astringent taste was reduced compared to the case where sodium caseinate was added. Further, even when CPP or sericin was added to the green tea leaf extract, no nuisance such as a rough feeling was felt, and no turbidity was generated.
On the other hand, when pea protein, soy protein, or sodium caseinate was added to the green tea leaf extract, a nuisance such as a rough feeling was felt, and turbidity also occurred.
From these things, it became clear that a preferable food and drink can be produced by using the processed green tea leaf product of the present invention.

[Example 3] Casein phosphopeptide and sericin inhibit bitterness and astringency on bitterness and astringency of high-concentration green tea Example: To leave the high-concentration green tea leaf extract prepared in Test Example 3 to room temperature and then reach a predetermined concentration CPP or sericin used in 1 was added and stirred for 1 minute to obtain a processed product of high-concentration green tea leaves.
About these high concentration green tea leaf processed products, sensory evaluation was performed by eight panelists, and bitterness and astringency were compared.
The bitter and astringent taste was evaluated on a 7-point scale of 1 (very weak) to 7 (very strong), with 7 additive-free high concentration green tea leaf extracts.
Table 3 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 3 shows the number of evaluators who performed each evaluation. Further, Table 3 also shows the presence or absence of turbidity occurring in the processed product of high-concentration green tea leaves.

[Comparative Example 3] Soybean protein and sodium casein inhibitory effect on bitterness and taste of high-concentration green tea Instead of CPP or sericin in Example 3, soybean protein or sodium caseinate used in Comparative Example 1 at a predetermined concentration was added. A high concentration green tea leaf processed product was obtained.
About these high concentration green tea leaf processed products, sensory evaluation was performed by eight panelists, and bitterness and astringency were compared.
The bitter and astringent taste was evaluated on a 7-point scale of 1 (very weak) to 7 (very strong), with 7 additive-free high concentration green tea leaf extracts.
Table 3 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 3 shows the number of evaluators who performed each evaluation. Further, Table 3 also shows the presence or absence of turbidity occurring in the processed product of high-concentration green tea leaves.

As shown in Table 3, the bitter and astringent taste of the high-concentration green tea leaf processed product to which CPP and sericin were added was not only reduced from the additive-free high-concentration green tea leaf extract, but also the bitter and astringent taste reduction effect was reported. The bitter and astringent taste was reduced as compared with those added with soy protein and sodium caseinate.
Moreover, even when CPP or sericin was added to the high-concentration green tea leaf extract, no nuisance such as a rough feeling was felt and no turbidity was generated.
On the other hand, when soy protein and sodium caseinate were added to the processed green tea leaf product, a sense of taste including a rough feeling was felt, and turbidity also occurred.
From these facts, it was clarified that preferable food and drink can be produced by using the processed product of high concentration green tea leaves of the present invention.

[Example 4] Binding experiment between CPP and catechins in high-concentration green tea 300 μL of high-concentration green tea leaf processed product containing 1.00% by weight of CPP prepared in Example 3 was subjected to ultrafiltration membrane (Amicon manufactured by Millipore) Filtration was performed using Ultra 0.5 (3k)) to obtain a filtrate.
As a comparison, 300 μL of the high-concentration green tea extract prepared in Test Example 3 was filtered using an ultrafiltration membrane (Amicon Ultra 0.5 (3k) manufactured by Millipore) to obtain a filtrate.

Table 4 shows the results obtained by analyzing the filtrate thus obtained by HPLC under the conditions shown in Measurement Example 2 above.
In the table, gallate type catechins refer to epigallocatechin-3-O-gallate, epicatechin-3-O-gallate, gallocatechin-3-O-gallate, and catechin-3-O-gallate. Non-gallate catechins include epigallocatechin, epicatechin, gallocatechin, and catechin.
The “gallate-type catechin residual rate” indicates the residual rate of gallate-type catechins in high-concentration green tea to which CPP is added, and was calculated using the following calculation formula (I).
Residual rate (%) = a / b × 100 (%) (I)
[Wherein a: concentration of gallate catechins in the filtrate of high concentration green tea added with CPP, b: concentration of gallate catechins in the filtrate of high concentration green tea without addition of CPP]

The “non-gallate catechin residual rate” indicates the residual rate of non-gallate catechins in high-concentration green tea to which CPP was added, and was calculated using the following calculation formula (II).
Residual rate (%) = c / d × 100 (%) (II)
[Where c: concentration of non-gallate catechins in the filtrate of high-concentration green tea added with CPP, d: concentration of non-gallate catechins in the filtrate of high-concentration green tea without addition of CPP]

  As shown in Table 4, it was revealed that CPP selectively binds to gallate catechins. From this, it is considered that CPP reduces the concentration of free gallate catechins contained in high-concentration green tea and suppresses the bitter taste of high-concentration green tea.

[Example 5] Manufacture of processed powdered green tea leaves After adding 5 parts by weight of the CPP used in Example 1 to 1000 parts by weight of the green tea leaf extract prepared in Test Example 2, the powdered green tea was freeze-dried. A processed leaf product was obtained.

[Example 6] Manufacture of tablets Using the processed powdered green tea leaf product obtained in Example 5, tablets having the compositions shown in Table 5 below were produced according to a conventional method. As a result, it was confirmed that bitterness and astringency were effectively suppressed in this tablet.

[Example 7] Production of candy Using the powdered green tea leaf processed product obtained in Example 5, a candy having the composition shown in Table 6 below was produced according to a conventional method. As a result, it was confirmed that bitterness and astringency were effectively suppressed in this candy.

[Example 8] Effect of CPP and sericin on bitter and astringent taste of cocoa 2 g of commercially available cocoa powder (cocoa powder content 22 to 24%) was dissolved in 100 mL of hot water and allowed to stand at room temperature. The CPP or sericin used in Example 1 was added to the cocoa beverage prepared in this manner so as to have a predetermined concentration, followed by stirring for 1 minute.
About these cocoa drinks, sensory evaluation was performed by 8 panelists, and bitterness and astringency were compared.
The bitter and astringent taste was evaluated on a 7-point scale from 1 (very weak) to 7 (very strong), with 5 cocoa drinks without additives. Table 7 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 7 shows the number of evaluators who performed each evaluation.

[Comparative Example 4] Soybean protein and sodium casein suppressive effect on bitterness and astringency of cocoa Instead of casein phosphopeptide or sericin of Example 8, the soy protein or sodium caseinate used in Comparative Example 1 at a predetermined concentration was added. Got a cocoa drink.
About these cocoa drinks, sensory evaluation was performed by 8 panelists, and bitterness and astringency were compared.
The bitter and astringent taste was evaluated on a 7-point scale from 1 (very weak) to 7 (very strong), with 5 cocoa drinks without additives. Table 7 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 7 shows the number of evaluators who performed each evaluation.

As shown in Table 7, the bitter and astringent taste of the cocoa beverage added with CPP and sericin was not only reduced from the additive-free cocoa beverage, but also added soy protein and sodium caseinate, which have been reported to have a bitter astringency reduction effect. The bitter and astringent taste was reduced. Further, even when CPP or sericin was added to the cocoa beverage, no off-flavors such as a rough feeling were felt, and no turbidity occurred.
On the other hand, when soy protein or sodium caseinate was added to the cocoa beverage, a sense of taste including a rough feeling was felt, and turbidity also occurred.
From these facts, it was revealed that preferable foods and drinks can be produced by using the bitter and astringent taste inhibitor containing the CPP or sericin of the present invention as an active ingredient.

[Test Example 4] Preparation of guava leaf extract 1000 g of hot water (ion-exchanged water) boiled in 10 g of dried guava leaf subdivided into commercially available tea packs is extracted for 5 minutes, and then the guava leaf is discarded together with the tea pack. The guava leaf extract obtained in step 1 was used as guava tea.

[Example 9] CPP and sericin inhibit bitterness and astringency of Guava tea bitterness and astringency After leaving the guava leaf extract prepared in Test Example 4 until it reaches room temperature, the CPP used in Example 1 to obtain a predetermined concentration Alternatively, sericin was added and stirred for 1 minute.
About these guava leaf extracts, sensory evaluation was performed by 10 panelists, and bitterness and astringency were compared.
The bitter and astringent taste was evaluated on a 7-point scale from 1 (very weak) to 7 (very strong), with the additive-free guava leaf extract as 7 points. Table 8 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 8 shows the number of evaluators who performed each evaluation.
Further, Table 8 also shows the presence or absence of turbidity generated in the guava leaf extract.

[Comparative Example 5] Soy protein and sodium casein suppressive effect on bitter and astringent taste of guava tea Instead of casein phosphopeptide or sericin in Example 9, soy protein or sodium caseinate used in Comparative Example 1 at a predetermined concentration was added. Thus, a guava leaf extract was obtained.
About these guava leaf extracts, sensory evaluation was performed by 10 panelists and bitterness and astringency were compared.
The bitter and astringent taste was evaluated on a 7-point scale from 1 (very weak) to 7 (very strong), with the additive-free guava leaf extract as 7 points.
Table 8 shows the average value of the evaluation points.
In addition, the presence or absence of off-flavors was also evaluated. The taste was evaluated as none (◯), slightly present (Δ), or present (×). Table 8 shows the number of evaluators who performed each evaluation. Further, Table 8 also shows the presence or absence of turbidity generated in the guava leaf extract.

As shown in Table 8, the bitter and astringent taste of the guava leaf extract to which CPP and sericin were added was not only reduced from the additive-free guava leaf extract, but also the soy protein and casein reported to have a bitter and astringent taste reducing effect. The bitter and astringent taste was reduced as compared with the one added with sodium.
Further, even when CPP or sericin was added to the guava leaf extract, no off-flavors such as a rough feeling were observed, and turbidity did not occur.
On the other hand, when soy protein or sodium caseinate was added to the guava leaf extract, a nuisance such as a rough feeling was felt, and turbidity also occurred.
From these facts, it was revealed that preferable foods and drinks can be produced by using the bitter and astringent taste inhibitor containing the CPP or sericin of the present invention as an active ingredient.

  According to the present invention, it is possible to provide a preferred form of beverage or food without the influence of bitterness or astringency. In particular, various processed tea leaf products containing a sufficient amount of catechins and theaflavins can be provided as beverages and foods in a preferable form without the influence of bitterness and astringency.

Claims (9)

  A bitter or astringent taste inhibitor for beverages or foods, comprising a casein phosphopeptide or sericin as an active ingredient.   The bitter or astringent taste inhibitor according to claim 1, wherein the beverage or food is a beverage or food containing polyphenol or alkaloid.   The bitter and astringent taste inhibitor according to claim 1, wherein the beverage or food is a beverage or food containing tannin, catechins, theaflavins, thealvidins or chlorogenic acid.   The bitter or astringent taste inhibitor according to claim 1, wherein the beverage or food is a beverage or food containing black tea, green tea, oolong tea, various health teas, coffee, cocoa and extracts thereof. A catechin-containing beverage or food characterized in that bitterness or astringency is suppressed by the addition of casein phosphopeptide. The catechin-containing beverage or food according to claim 5, wherein the amount of casein phosphopeptide added is 0.001 to 50 parts by mass with respect to 1000 parts by mass of the beverage or food. A processed tea leaf product in which bitterness or astringency is suppressed by addition of casein phosphopeptide, wherein the tea leaf processed product is a tea leaf extract, suspension, granulated product, pulverized product, and the extract. Or the said tea leaf processed product which is 1 type chosen from the dry powder of a suspension. The tea leaf processed product according to claim 7, wherein the amount of casein phosphopeptide added is 0.01 to 100 parts by mass with respect to 1 part by mass of solid content derived from tea leaves. A beverage or food comprising the processed tea leaf product according to claim 7 or 8.