JP2012110247A - Method for producing beverage or food having reduced bitterness or astringency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple method for producing a beverage or food having sufficiently reduced bitterness or astringency at a low cost.SOLUTION: The method for producing the beverage or food having the reduced bitterness or astringency includes the following steps 1 and 2: step 1: a step for allowing bitter or astringent components to bond with a polyamino acid by adding the polyamino acid obtained by polycondensing only a basic amino acid as a monomer by an amide bond, or a polyamino acid obtained by polycondensing only a neutral amino acid as a monomer by the amide bond, or a mixture of these polyamino acid to the beverage or food containing the bitter or astringent component; and step 2: a step for removing the bonded product of the bitter or astringent component with the polyamino acid formed in the step 1 from the beverage or food.

Description

The present invention relates to a beverage and food production method with reduced bitterness and astringency.
Specifically, after using a polyamino acid obtained by polycondensation of only basic amino acids or a polyamino acid obtained by polycondensation of only neutral amino acids, a bitter and astringent ingredient contained in a beverage or food is bound to the polyamino acid, and then the beverage And a method for producing a beverage or food with reduced bitterness or astringency by a method of removing the bound product from the food.

The bitterness and astringency of beverages and foods are important elements of palatability as characteristics of the beverages and foods. On the other hand, too strong bitterness and astringency, on the other hand, are factors that impair the flavor of beverages and foods. Therefore, it is required to reduce the bitterness and astringency of beverages and foods.
For this reason, various attempts have been made to remove bitterness components and astringency components contained in beverages and foods.

As a method for removing bitter substances and bitter substances in beverages and foods, a method of adsorbing and removing tannin using polyvinylpolypyrrolidone resin (Patent Document 1 and Patent Document 2), and astringency and bitterness of beverages using protamine An improved method (Patent Document 3) has been reported.
However, since the polyvinyl polypyrrolidone resin widely binds to polyphenol, it is not suitable for selectively removing gallate type catechins and gallate type theaflavins having strong bitterness and astringency.

  In order to overcome this drawback, a method of selectively removing gallate catechins using a polyvinylpolypyrrolidone resin has been proposed (Patent Document 4). In this method, tea leaves are extracted with warm water at 40 to 80 ° C., a step of preparing a tea leaf extract in which the proportion of gallate catechins in the total catechins is 50% or less, and the tea leaf extract is 60 to 90 ° C. Is a method for producing a tea-based composition comprising a step of reducing the proportion of gallate-type catechins in the tea leaf extract to the total catechins to 30% or less by contacting with polyvinylpolypyrrolidone in the temperature range.

However, the method of selectively removing gallate catechins using the above-mentioned polyvinyl polypyrrolidone resin is a complicated method. In addition, the method for producing a tea extract using polyvinylpolypyrrolidone is disadvantageous in terms of cost because it requires a large amount of expensive resin.
Moreover, since the method using protamine is a method of removing the produced insoluble matter, protamine with strong astringency remains in the beverage, which affects the flavor of food and drink.

On the other hand, for the binding of polyamino acid consisting of only basic amino acid or only neutral amino and polyphenol, it relates to the binding of polyproline consisting only of neutral amino acid proline and high molecular polyphenol proanthocyanidin. There is a report (Non-Patent Document 1).
However, there has been no report that a polyamino acid composed of only basic amino acids or neutral amino acids binds to catechins which are low molecular weight polyphenols to suppress bitterness and astringency.

Japanese Patent Laid-Open No. 9-220055 JP 2000-41577 A JP-A-6-153875 Japanese Patent Application Laid-Open No. 2004-159597

The Journal of Biological Chemistry, 256, 4494-4497 (1981)

  An object of the present invention is to solve the above-mentioned problems in the prior art, and to provide a method for producing a beverage or food with sufficiently reduced bitterness and astringency, and a simple and low-cost method.

The present inventors have found that a polyamino acid composed only of a basic amino acid or a neutral amino acid selectively binds catechins, theaflavins, thearvidins and chlorogenic acid, which are polyphenols in beverages , and the results Thus, the inventors have found a method capable of easily producing beverages and foods with reduced bitterness and astringency without affecting the flavor, and have completed the present invention.

That is, the present invention
(1) A method for producing a beverage or food with reduced bitterness or astringency, comprising the following steps 1 and 2.
Step 1: A polyamino acid in which only a basic amino acid is polycondensed by an amide bond as a monomer or a polyamino acid in which only a neutral amino acid is polycondensed by an amide bond as a monomer to a food or drink containing a bitter or astringent ingredient Step of adding a mixture of these polyamino acids to combine a bitter or astringent component with a polyamino acid Step 2: Removing a combination of the bitter or astringent component and the polyamino acid produced in Step 1 from a beverage or food Process

(2) Further, the present invention is characterized in that in the production method of (1), the removal in step 2 is the following removal method (a), (b), (c) or (d). .
(A) Removal method by ultrafiltration (b) Removal method by centrifugal separation (c) Method of removing by causing precipitation of a combination of a bitter or astringent component and a polyamino acid by adding a water-soluble organic solvent (D) A method in which a polyamino acid is fixed to a solid carrier, and a combined product of the bitterness or astringency component and the polyamino acid is removed by taking out the fixed carrier from the beverage or food.

(3) Furthermore, the present invention relates to the production methods of (1) and (2) above,
The beverage or food is a beverage or food containing polyphenol or alkaloid; it is a beverage or food containing catechins, theaflavins, thearvidins or chlorogenic acid; black tea, green tea, oolong tea, coffee, cocoa and its It is characterized by being a drink or food containing an extract.
(4) Furthermore, the polyamino acid is obtained by polymerizing the same type of amino acid as a monomer;
The basic amino acid is at least one selected from the group consisting of arginine, histidine and lysine;
Each of the neutral amino acids is at least one selected from the group consisting of alanine, glycine, proline, valine, leucine, isoleucine, phenylalanine, tyrosine, tryptophan, cysteine, methionine, asparagine, glutamine, serine and threonine. And

(5) Furthermore, the present invention provides the production methods of (1) and (2),
The molecular weight of the polyamino acid is 500 to 100,000,
The amount of polyamino acid added is 0.001 to 50 parts by mass with respect to 1,000 parts by mass of beverage or food, respectively.

  According to the present invention, it is possible to easily produce a beverage or food with reduced bitterness or astringency without affecting the flavor of the beverage or food. In particular, catechins, which are the main factors of bitterness or astringency, particularly gallate catechins with a strong bitterness or astringency can be selectively and efficiently removed, so that a beverage or a bitterness or astringency sufficiently reduced Can provide food.

The present invention is described in detail below.
[I] Binding step of bitter or astringent components (1) Polyamino acid In the present invention, a polyamino acid is a polyamino acid obtained by polycondensation of only a basic amino acid by a peptide bond as a monomer, or neutral as a monomer It refers to a polyamino acid in which only amino acids are polycondensed by peptide bonds, or a mixture of these polyamino acids. “Basic amino acid only” means that the monomer constituting the polymer is only a basic amino acid and does not contain an acidic amino acid or a neutral amino acid. Accordingly, the polyamino acid obtained by polycondensation of only basic amino acids by peptide bonds is one or more selected from the group consisting of lysine, arginine and histidine having a basic side chain. Monomer.

  In addition, the meaning of `` neutral amino acid only '' is the same, and polyamino acids in which only neutral amino acids are polycondensed by peptide bonds are alanine, glycine, and proline (with no dissociation group in the side chain). proline), valine, leucine, isoleucine, phenylalanine, tyrosine, tryptophan, cysteine, methionine, asparagine, glutamine ( One or more selected from the group consisting of glutamine), serine and threonine are used as monomers.

Polyamino acids in which the same type of amino acid is polymerized as the monomer are preferable, and the amino acids constituting the polyamino acids are preferably those in which the amino group at the alpha position and the carboxyl group have an amide (peptide) bond, as in normal proteins. However, the present invention is not limited to this.
Specifically, polyarginine, polyhistidine, polylysine, polyalanine, polyglycine, polyproline, polyvaline, polyleucine, polyisoleucine, polyphenylalanine, polytyrosine, polytryptophan, polycysteine, polymethionine, polyasparagine, polyglutamine One or more selected from polyserine and polythreonine are used.
That is, a polyamino acid composed of a basic amino acid and a polyamino acid composed of a neutral amino acid can be used alone, or a mixture of both can be used.

When the polyamino acid 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 the polyamino acid in the present invention is preferably 500 to 100,000, particularly preferably 500 to 30,000, and most preferably 3,000 to 25,000.
The synthesis of polyamino acids is mainly carried out by decarboxylation polycondensation of N-carboxyamino acid anhydride (N-carboxylic acid anhydride, NCA). Polymerization by an activated NCA type polymerization mechanism using a tertiary amine as an initiator in an organic solvent is commonly used because it has a high polymerization rate and is easy to obtain a high molecular weight one.
As the polyamino acid in the present invention, a chemically synthesized commercially available product can be used as it is.

(2) Beverages or foods containing bitterness or astringency components Beverages or foods that can reduce bitterness or astringency in the present invention refers to beverages and foods that have a bitterness or astringency that may affect the taste. Specifically, it is a beverage or food containing polyphenol or alkaloid as a bitter substance.
Examples thereof include black tea, green tea, oolong tea, extracts and concentrates thereof, and foods containing tea leaf materials, which contain polyphenol component catechins, theaflavins, and thealvidins as bitter substances.
Further, as a bitter substance, there may be mentioned coffee containing polyphenol component chlorogenic acid or alkaloid caffeine, an extract or concentrate thereof, and food containing coffee beans.
Furthermore, cocoa and chocolate made from cocoa beans containing catechins of polyphenol components and the alkaloid theobromine as bitter substances are also included.

(3) Use amount of polyamino acid and binding with bitterness or astringency components In general, 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, the polyamino acid itself does not have a unique flavor, and in the present invention, since the added polyamino acid is removed from the beverage or food, there is no upper limit on the amount used.
However, considering the cost, if the effect can be expected, the addition amount should be low. The amount of polyamino acid added is generally 0.001 to 50 parts by weight, preferably 0.01 to 10 parts by weight with respect to 1,000 parts by weight of beverage or food. If the amount is less than 0.001 part by mass, a sufficient bitterness or astringency suppressing effect cannot be obtained. On the other hand, if the amount exceeds 50 parts by mass, the cost increases and the cost increases.
The combination with the bitter taste astringency component is as follows: Add the polyamino acid to the beverage or food solution in the above amount, and immediately after mixing at a temperature of 5 to 90 ° C. or for 1 second to 30 minutes. The polyamino acid and the bitter or astringent component in the food and drink are combined. Such bonds are due to intermolecular interactions such as hydrophobic bonds, hydrogen bonds, and ionic bonds.

(II) Step of removing bitterness or astringency components The polyamino acid in the present invention binds to catechins, particularly gallate catechins having a strong bitterness or astringency, so after mixing with beverages or foods containing catechins, By removing the combined product of the polyamino acid and catechins, the concentration of catechins contained in beverages and foods can be reduced. As a result, the bitterness and astringency of beverages and foods can be reduced.

  The polyamino acid removal method in the present invention is described below: (a) ultrafiltration treatment with a separation membrane, (b) treatment by centrifugation, (c) treatment with an organic solvent, and (d) polyamino acid bound to a carrier. The polyamino acid can be efficiently removed by treatment with one or more separation methods selected from the use of, but is not limited to these methods.

(A) Treatment with Separation Membrane This is a method of removing a combined product of a polyamino acid which is a polymer and a bitter astringency material by membrane (filtration) treatment. As the type of membrane, an ultrafiltration membrane or a dialysis membrane can be used.
(B) Treatment by centrifugation This is a method for centrifuging a beverage or food extract to precipitate and remove a combined product of a polyamino acid which is a polymer and a bitter and astringent substance.

(C) Treatment with an organic solvent After adding a water-soluble organic solvent such as ethanol to precipitate a combined product of a polyamino acid that is a polymer and a bitter astringent material, the combined product is removed by filtration or centrifugation, In this method, the obtained solution is concentrated to remove the organic solvent.
(D) Use of a polyamino acid bound to a carrier A polyamino acid bound to a carrier and a solid polyamino acid-bitter taste product are separated from the beverage or food extract by filtration, centrifugation, magnetic force, etc. and removed. It is a method to do. As the carrier used in the present invention, silica gel, polyamide gel, magnetic beads and the like modified so that polyamino acids can be bonded to the surface can be used.

  The beverage or food extract obtained through the removal step by the separation methods (a) to (d) described above can be used as it is as a beverage or food with reduced bitterness and astringency, but it is easy to work and preserve. Considering the good nature, water can be removed by vacuum concentration or freeze-drying and used as a powder.

  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]
The specimen subjected to the binding experiment was filtered using an ultrafiltration membrane (Amicon Ultra 0.5 (3k) manufactured by Millipore), and the filtrate was analyzed for catechins using the following high performance liquid chromatography (HPLC). The remaining amount was quantified.
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. 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 extract 1000g of hot water (ion-exchanged water) boiled in 10g of tea leaves (produced in India) divided into commercially available tea packs, extracted for 5 minutes, then discarded tea leaves together with tea packs As a result, a black tea extract was obtained.

[Test Example 2] Preparation of green tea extract liquid Green tea leaves (produced in Shizuoka) divided into commercially available tea packs 10 g of hot water (ion-exchanged water) boiled in 10 g were extracted for 5 minutes, and then the green tea leaves were discarded together with the tea packs. As a result, a green tea extract was obtained.

[Test Example 3] Binding experiment between various polyamino acids and EGCG The polyamino acids used in the tests are shown in Table 1 below.

  20 mg / mL polyamino acid solution prepared with 50 mM phosphate buffer (pH 6.4), 6 umol / mL epigallocatechin-3-O-gallate (hereinafter referred to as “EGCG”) solution and the above phosphate buffer Were mixed to prepare a mixed solution of polyamino acid having a predetermined concentration and EGCG of 2 umol / mL. The mixture was stirred for 15 minutes at room temperature, and then filtered using an ultrafiltration membrane (Amicon Ultra 0.5 (3k) manufactured by Millipore) to obtain a filtrate.

Table 2 shows the results of analyzing the filtrate thus obtained by HPLC under the conditions shown in the above measurement examples. In the table, “EGCG residual ratio” indicates the residual ratio of EGCG in the EGCG solution to which various test substances have been added, and was calculated using the following calculation formula (I).
Residual rate (%) = b / a × 100 (%) (I)
[Wherein a: EGCG concentration in the filtrate to which a phosphate buffer is added instead of the test substance,
b: EGCG concentration in filtrate added with test substance]

As shown in Table 2, polyarginine, polyhistidine and polylysine, which are polyamino acids composed only of basic amino acids, and polyglycine and polyproline, which are polyamino acids composed only of neutral amino acids, bind to EGCG. It became clear to do.
On the other hand, it has been clarified that polyaspartic acid, which is a polyamino acid composed only of acidic amino acids, does not bind to EGCG at all.
Therefore, various polyamino acids composed of only basic amino acids or only neutral amino acids can reduce the free EGCG concentration contained in beverages and foods, and reduce the bitterness and astringency of beverages and foods containing EGCG. Conceivable.

[Example 1] Preparation of black tea with reduced catechins 75 uL of a 20 mg / mL polyamino acid solution prepared with 50 mM phosphate buffer (pH 6.4) and 225 uL of black tea extract prepared in Test Example 1 were mixed. After stirring for 15 minutes at room temperature, the mixture was filtered using an ultrafiltration membrane (Amicon Ultra 0.5 (3k) manufactured by Millipore) to obtain a filtrate.

The results obtained by analyzing the filtrate thus obtained by HPLC under the conditions shown in the above measurement examples are shown in Table 3.
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 black tea to which various polyamino acids are added, and was calculated using the following calculation formula (II).
Residual rate (%) = d / c × 100 (%) (II)
[Where c: concentration of gallate catechins in the filtrate added with phosphate buffer instead of the test substance, d: concentration of gallate catechins in the filtrate added with the test substance]
The “non-gallate catechin residual rate” indicates the residual rate of non-gallate catechins in black tea added with various polyamino acids, and was calculated using the following formula (III).
Residual rate (%) = f / e × 100 (%) (II)
[Wherein e: concentration of non-gallate catechins in the filtrate added with phosphate buffer instead of the test substance, f: concentration of non-gallate catechins in the filtrate added with the test substance]

As shown in Table 3, by using polyarginine, polyhistidine, and polylysine, which are polyamino acids composed only of basic amino acids, and polyglycine and polyproline, which are polyamino acids composed only of neutral amino acids. Thus, a black tea extract from which gallate-type catechin was selectively removed could be obtained.
On the other hand, such a black tea extract could not be obtained with polyaspartic acid, which is a polyamino acid composed only of acidic amino acids.
From this, by using a polyamino acid composed of only basic amino acids or only neutral amino acids, gallate catechins contained in black tea are removed, and a black tea extract with reduced bitterness and astringency is obtained. It is considered possible.

[Example 2] Preparation of green tea with reduced catechins 75 uL of a 20 mg / mL polyamino acid solution prepared with a 50 mM phosphate buffer (pH 6.4) and 225 uL of a green tea extract prepared in Test Example 2 were mixed. After stirring for 15 minutes at room temperature, the mixture 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 the above measurement examples.
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 ratio” indicates the residual ratio of gallate-type catechins in green tea to which various polyamino acids are added, and was calculated using the following calculation formula (II).
Residual rate (%) = d / c × 100 (%) (II)
[Where c: concentration of gallate catechins in the filtrate added with phosphate buffer instead of the test substance, d: concentration of gallate catechins in the filtrate added with the test substance]
The “non-gallate catechin residual rate” indicates the residual rate of non-gallate catechins in green tea to which various polyamino acids are added, and was calculated using the following calculation formula (III).
Residual rate (%) = f / e × 100 (%) (III)
[Wherein e: concentration of non-gallate catechins in the filtrate added with phosphate buffer instead of the test substance, f: concentration of non-gallate catechins in the filtrate added with the test substance]

  As shown in Table 4, by using polyarginine, polyhistidine, polylysine, which are polyamino acids composed only of basic amino acids, and polyglycine, polyproline, which are polyamino acids composed only of neutral amino acids Thus, a green tea extract from which gallate-type catechin was selectively removed could be obtained. On the other hand, such a green tea extract could not be obtained with polyaspartic acid, which is a polyamino acid composed only of acidic amino acids. Therefore, by using a polyamino acid composed of only basic amino acids or only neutral amino acids, gallate catechins contained in green tea are removed, and a green tea extract with reduced bitterness and astringency is obtained. It is considered possible.

[Example 3] Preparation of black tea with reduced bitterness and astringency To the black tea extract prepared in Test Example 1, polyglycine and polyproline were added to a predetermined concentration and mixed uniformly. Next, 4 mL of this black tea extract was centrifuged at 12000 rpm for 30 minutes. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the black tea extract without additives. Table 5 shows the average value of the evaluation points. Table 5 shows the results of evaluating the presence or absence of off-flavors.

[Comparative Example 1] Black tea prepared using protamine A similar concentration of protamine was added in place of the polyglycine and polyproline of Example 3 and the same operation was performed. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the black tea extract without additives. Table 5 shows the average value of the evaluation points. Table 5 shows the results of evaluating the presence or absence of off-flavors.

  As shown in Table 5, the bitter taste of the centrifugal supernatant of the black tea extract to which polyglycine or polyproline was added was reduced from that of the non-added centrifugal supernatant, no off-flavor was observed, and polyglycine or polyproline was used. It became clear that tea with reduced bitterness and astringency can be made. On the other hand, when protamine was used, black tea with reduced bitterness and astringency could not be produced due to the strong off-taste.

[Example 4] Preparation of green tea with reduced bitterness and astringency To the green tea extract prepared in Test Example 2, polyhistidine and polyproline were added to a predetermined concentration and mixed uniformly. Next, 4 mL of this green tea extract was centrifuged at 12000 rpm for 30 minutes. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the green tea extract with no additive added. Table 6 shows the average value of the evaluation points. Table 6 shows the results of evaluating the presence or absence of off-flavors.

[Comparative Example 2] Green tea prepared using protamine The same procedure was performed by adding protamine at a predetermined concentration in place of the polyhistidine and polyproline of Example 4. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the green tea extract with no additive added. Table 6 shows the average value of the evaluation points. Table 6 shows the results of evaluating the presence or absence of off-flavors.

  As shown in Table 6, the bitter taste of the centrifugal supernatant of the green tea extract to which polyhistidine or polyproline was added was reduced from that of the additive-free centrifugal supernatant, and no off-flavor was observed. Polyhistidine or polyproline was used. It became clear that green tea with reduced bitterness and astringency could be created. On the other hand, when protamine was used, green tea with reduced bitterness and astringency could not be created due to its strong off-taste.

[Example 5] Preparation of cocoa with reduced bitterness and astringency 4 g of commercially available cocoa powder (cocoa powder content 22-24%) was dissolved in 100 mL of hot water and allowed to stand until it reached room temperature. Polyhistidine and polyproline were added to the cocoa beverage thus prepared so as to obtain a predetermined concentration, followed by thorough stirring. Next, 4 mL of this cocoa beverage was centrifuged at 12000 rpm for 30 minutes. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the additive-free cocoa beverage. Table 7 shows the average value of the evaluation points. Table 7 shows the results of evaluating the presence or absence of off-flavors.

[Comparative Example 3] Cocoa prepared using protamine The same procedure was performed by adding protamine at a predetermined concentration instead of polyhistidine and polyproline in Example 5. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the additive-free cocoa beverage. Table 7 shows the average value of the evaluation points. Table 7 shows the results of evaluating the presence or absence of off-flavors.

  As shown in Table 7, the bitter taste of the centrifugal supernatant of the cocoa beverage to which polyhistidine or polyproline was added was lower than that of the non-added centrifugal supernatant, and no off-flavor was observed, using polyhistidine or polyproline. It became clear that cocoa beverages with reduced bitterness and astringency can be produced. On the other hand, when protamine was used, a cocoa beverage with reduced bitterness and astringency could not be produced due to its strong off-taste.

[Example 6] Preparation of coffee with reduced bitter and astringent taste 2 g of commercially available instant coffee was dissolved in 100 mL of hot water and allowed to stand at room temperature. Polyhistidine was added to the coffee beverage thus prepared to a predetermined concentration and mixed to be uniform. Next, 4 mL of this coffee beverage was centrifuged at 12000 rpm for 30 minutes. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the additive-free coffee drinks. Table 8 shows the average value of the evaluation points. Table 8 shows the results of evaluating the presence or absence of off-flavors.

[Comparative Example 4] Coffee made using protamine A similar concentration of protamine was added in place of the polyhistidine of Example 6 and the same operation was performed. The supernatant thus obtained was subjected to sensory evaluation by three panelists, and the 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 centrifugal supernatants of the additive-free coffee drinks. Table 7 shows the average value of the evaluation points. Table 8 shows the results of evaluating the presence or absence of off-flavors.

  As shown in Table 8, the bitterness and astringency of the centrifuge supernatant of the coffee beverage added with polyhistidine is lower than that of the addition-free centrifuge supernatant, and no off-flavor is observed, and the bitterness and astringency are reduced using polyhistidine. It was revealed that the coffee beverages made can be made. On the other hand, when protamine was used, a coffee beverage with reduced bitterness and astringency could not be produced due to the strong off-flavor.

[Example 7] Production method of tea beverage using polyproline bound to solid phase carrier 20 mL of 0.01 M pyridine washing solution was added to 2.5 mL of magnetic microbead suspension ("Biomagplus amine" manufactured by Polyscience). After stirring, magnetic microbeads were collected by magnetic force, and the supernatant was discarded. This operation was repeated 4 times.
Thereafter, 10 mL of 5% glutaraldehyde solution was added and stirred for 3 hours. Next, the supernatant was discarded while collecting magnetic microbeads by magnetic force, 20 mL of 0.01 M pyridine washing solution was added and stirred, and then magnetic microbeads were collected by magnetic force, and the supernatant was discarded. The washing operation using this pyridine washing solution was repeated 4 times.
Next, 10 mL of 50 mM phosphate buffer (pH 6.4) in which 65 mg of polyproline was dissolved was added to the magnetic microbeads and stirred for 20 hours.
Thereafter, magnetic microbeads were collected by magnetic force, and the supernatant was discarded. 20 mL of 50 mM phosphate buffer (pH 6.4) was added to the collected magnetic microbeads and stirred, and then magnetic microbeads were collected by magnetic force, and the supernatant was discarded. This washing operation was repeated 4 times.
In this way, 100 mg of magnetic microbeads immobilized with polyproline were mixed with 100 g of the black tea extract obtained in Test Example 1 or 100 g of the green tea extract obtained in Test Example 2, and after stirring well for 15 minutes, at 8000 rpm Centrifugation for 10 minutes was performed, and a black tea extract or a green tea extract was obtained as a supernatant.

[Example 8] Green tea extract-containing powder composition To 1000 parts by weight of the green tea extract obtained in Test Example 2, 2 parts by weight of polyhistidine was added, mixed uniformly, and then centrifuged at 12000 rpm for 30 minutes. went. The centrifugal supernatant thus obtained was freeze-dried to obtain a green tea extract-containing powder composition.

[Example 9] Manufacture of tablets Using the tea extract-containing powder composition obtained in Example 8, tablets having the compositions shown in Table 9 below were prepared according to a conventional method.

Example 10 Production of Candy Candy having the composition shown in Table 10 below was prepared according to a conventional method.

  According to the present invention, a beverage or food with reduced bitterness and astringency can be provided by a simple and low-cost production method without affecting the original flavor of food and drink.

Claims (10)

A method for producing a beverage or food with reduced bitterness or astringency, comprising the following steps 1 and 2.
Step 1: A polyamino acid in which only a basic amino acid is polycondensed by an amide bond as a monomer or a polyamino acid in which only a neutral amino acid is polycondensed by an amide bond as a monomer to a food or drink containing a bitter or astringent ingredient Step of adding a mixture of these polyamino acids to combine a bitter or astringent component with a polyamino acid Step 2: Removing a combination of the bitter or astringent component and the polyamino acid produced in Step 1 from a beverage or food Process 2. The production method according to claim 1, wherein the removal in step 2 is the following removal method (a), (b), (c) or (d).
(A) Removal method by ultrafiltration (b) Removal method by centrifugal separation (c) Method of removing by causing precipitation of a combination of a bitter or astringent component and a polyamino acid by adding a water-soluble organic solvent (D) A method in which a polyamino acid is fixed to a solid carrier, and a combined product of the bitterness or astringency component and the polyamino acid is removed by taking out the fixed carrier from the beverage or food.   The method according to claim 1 or 2, wherein the beverage or food is a beverage or food containing polyphenols or alkaloids.   The production method according to claim 1 or 2, wherein the beverage or food is a beverage or food containing catechins, theaflavins, thearvidins or chlorogenic acid.   The production method according to claim 1 or 2, wherein the beverage or food is a beverage or food containing black tea, green tea, oolong tea, coffee, cocoa and an extract thereof.   The production method according to claim 1, wherein the polyamino acid is obtained by polymerizing the same type of amino acid as a monomer.   The method according to claim 1, wherein the basic amino acid is at least one selected from the group consisting of arginine, histidine and lysine.   The neutral amino acid is at least one selected from the group consisting of alanine, glycine, proline, valine, leucine, isoleucine, phenylalanine, tyrosine, tryptophan, cysteine, methionine, asparagine, glutamine, serine and threonine. The manufacturing method according to claim 1.   The production method according to claim 1, wherein the molecular weight of the polyamino acid is 500 to 100,000.   The production method according to claim 1, wherein the amount of polyamino acid added is 0.001 to 50 parts by mass with respect to 1,000 parts by mass of the beverage or food.