JPH08242771A - Japanese style confection and its production - Google Patents

Abstract

PURPOSE: To obtain a Japanese style confection which mainly comprises thick malt syrup and shows excellent moisture retention and stability by admixing a partially heat-denatured whey protein and salts thereto. CONSTITUTION: (A) A heat-denatured whey protein powder which is prepared by heating a solution obtained by dissolving desalted whey protein is a concentration of less than 15wt.% in water at 55-120 deg.C and drying the aqueous solution is used in amount of more than 1wt.%, preferably more than 5wt.% and (B) a monovalent or divalent salt (preferably calcium chloride, calcium lactate, magnesium chloride, sodium chloride, potassium chloride, sodium ascorbate and the like) is added thereto and, the partially heated whey protein is gelled to give the objective Japanese style confection whose water retention and stability are improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a Japanese confectionery containing bean paste as a main component, which has improved water retention and stability, and a method for producing the same.

[0002]

2. Description of the Related Art Japanese confectionery is a food of a great variety. Among them, fresh confectionery whose main ingredient is bean paste prepared from red beans and green beans is a typical Japanese confectionery. Examples of such raw confectionery include confectionery collectively referred to as a paste. This is a mixture of raw sweetened bean paste, shiratama powder, fertilizer, etc., kneaded with heat and kneaded well, then added agar, kneaded with heat and kneaded well, and kneaded yokan or water yokan in a mold,
Alternatively, a kudzu paste prepared by adding starch to a sweetened bean paste may be used. In each of these raw confectionery, white ball powder, starch or agar is added in order to impart viscosity to the bean jam, and their texture and shape are maintained by their gelation action. In particular, Mizuyokan is a confection that makes the best use of the gelling action of agar and is characterized by a unique refreshing feeling. All of these pastes use a large amount of sugar, and the water retention of the sugar maintains the stability and storability of the product. For example,
The moisture content of kneaded yokan is about 26%, which is not particularly low in fresh confectionery, but the sugar is in a state of holding the moisture, which reduces the water activity and improves storage stability. And the water retention is improved. In recent years, it has been attempted to partially use additives having a gelling ability such as guar gum and gelatin instead of agar. JP-A-60
Japanese Patent No. 94061 discloses a method for producing a layered Japanese confectionery using gelatin as a gelling agent, and Japanese Patent Application Laid-Open No. 4-27175 discloses a technique of using esterified or crosslinked starch. It is disclosed. These techniques cannot be commonly used in Japanese sweets containing soybean paste as a main component, which is a so-called paste, and they do not have the effect of improving water retention and storage stability of the prepared Japanese sweets. In addition, the characteristics of raw confectionery vary greatly depending on the type and quality of the gelling agent used for gelling, such as starch, kudzu powder, shiratama powder, and agar. It is necessary and it is difficult to standardize the work. Furthermore, depending on the type and amount of gelling agent used, there is a large difference in the water retention and stability of raw confectionery. Especially in recent years, sweets with reduced sweetness have been demanded,
It has become common to control sugar usage to an extremely low level, replacing traditional traditional methods. For this reason, it may be possible to rely on conventional craftsmanship.

[0003]

The present inventors have studied the characteristics of whey protein, and as a result, whey protein is usually a globular protein. It has been found that soluble aggregates formed in a chain form are formed, and when a salt is added to the soluble aggregates, an insoluble gelation product is formed. In order to efficiently prepare this soluble aggregate, the concentration of an aqueous solution of whey protein is adjusted so as not to gel even when heat-treated, and the heat treatment is performed at a temperature of 55 to 120 ° C. for a time of 60 minutes or less. I found good things to do. It was also found that the soluble aggregate can be pulverized by spray-drying or freeze-drying treatment, and by dissolving the powder in water, the soluble aggregate is restored. This soluble aggregate was found to be useful as a raw material for meat processing and desserts because it forms an irreversible gel by freezing or salt, and has already applied for a patent (Japanese Patent Application No. 4-11234). issue). The present inventors have conducted further research based on such findings, and the above-mentioned soluble aggregates have improved water retention and stability in Japanese sweets containing sweetened bean paste as a main component as shown above. Furthermore, they have found that the storage stability can be significantly improved.

The present invention was made on the basis of the above-mentioned findings. By mixing a partially heat-denatured whey protein and a monovalent or divalent salt, the partially heat-denatured whey protein is gelled. It is an object of the present invention to provide a Japanese confectionery containing bean paste as a main component, which has improved water retention and stability. In addition, in the present invention, confectionery containing paste as a main component and referred to as a paste is used in the following term of Japanese confectionery. These Japanese sweets are kneaded paste, kneaded yokan,
Including water yokan and steamed yokan. Furthermore, in the present invention, the raw material for sweets containing bean paste as the main component is a partially heat-denatured whey protein content of 1.0% by weight or more and a monovalent or divalent salt which is harmless to food hygiene to 0% whey protein. It is another object of the present invention to provide a method for producing a Japanese confectionery containing 0.05% by weight or more of the partially heat-denatured whey protein to gel, thereby obtaining a Japanese confectionery having improved water retention and stability.

[0005]

Means for Solving the Problems The present invention provides an aqueous whey protein solution prepared at a concentration that does not heat-coagulate when heated at a temperature higher than the heat denaturation temperature of whey protein as described above, at the heat denaturation temperature of the protein. A partially heated denatured product of whey protein obtained by heating and a harmless monovalent or divalent salt are used for the production of a Japanese confectionery containing sweetened bean paste as a main component. It is known that an aqueous whey protein solution usually solidifies by heating and forms a brittle gel when the protein concentration is 15% or more. In order not to form such a gel by heating, the protein concentration is 15% or less, preferably 10% or less, particularly preferably 8 to 10%.
When an aqueous solution adjusted to a concentration of less than or equal to 55% is heated at a temperature of 55 ° C or higher and 120 ° C or lower, preferably 65 ° C to 95 ° C, the protein is partially denatured and a hydrophobic portion appears on the molecular surface of whey protein, which is a globular protein. Come on. When the whey protein thus prepared and a monovalent or divalent salt are used for the production of Japanese sweets containing bean paste as a main component, especially kneaded products, the hardness and texture of the Japanese sweets may vary depending on the gelation state of the whey protein. Can be adjusted freely, and it becomes possible to improve the water retention of Japanese confectionery, which was difficult with the conventional techniques, and to impart storage stability. It is known that this whey protein aqueous solution is gelated by adding salt ions or increasing the concentration of salt ions around protein molecules by freezing. The present invention takes advantage of the fact that such protein properties can maintain water retention and stability in place of starch, agar, shiratama powder, etc. used in conventional confectionery production. The characteristics of this aqueous whey protein solution vary depending on the hydrophobicity of the whey protein. Normally, the whey protein is adjusted to pH 6 to 9 under the above-mentioned concentration conditions and heated for 5 to 30 minutes. An aqueous solution in which the protein is denatured into a soluble aggregate can be obtained. The method for preparing this aqueous protein solution is described in JP-A-5-6455.
It can be carried out according to the method disclosed in JP-A-0.

When the whey protein solution is heated at a protein concentration that does not coagulate by heating, a certain denaturation state occurs and S
At the same time as the H / SS exchange reaction, the degree of hydrophobicity also increases. As a result, protein molecules associate with each other to form soluble aggregates. This state is called a soluble aggregate. The present invention can easily adjust the texture such as the hardness and the viscosity of Japanese confectionery, especially the paste containing sweetened bean paste as a main ingredient, by appropriately combining the soluble aggregates and salts for gelling the same, and It has novelty and inventive step where the storage stability can be greatly improved. No gel is formed at the stage of this soluble aggregate, but this soluble aggregate is subjected to freeze / thaw treatment as described above (Japanese Patent Laid-Open No. 3-280).
No. 834, Japanese Patent Application Laid-Open No. 3-277249), salts such as salt and calcium are added (Japanese Patent Application Laid-Open No. 5-64).
No. 550), acidifying the solution (JP-A 2-1)
24067), soluble aggregates form a three-dimensional network structure, resulting in an irreversible gel. The gel thus obtained is characterized by high water retention and does not undergo the aging that starch exhibits. Further, since water is retained in the gel body, it is considered that it contributes to the improvement of storage stability.

As a method for heating the whey protein aqueous solution for obtaining a partially heated denatured product of whey protein used for the production of Japanese confectionery of the present invention, it is preferable to heat at 55 to 120 ° C. at which whey protein is denatured by heating. It is particularly preferable to heat at 65 ° C to 95 ° C. 55
Protein denaturation does not occur below ℃. The heating time is preferably maintained at that temperature for 1 second to 60 minutes, particularly preferably 30 to 60 minutes. If the heating time is short, denaturation does not occur and the FI value defined below becomes low, and if it is high, browning and toxic lysinoalanine are produced, which is not preferable. The whey protein concentration is 0.5 to 1
It is 5%, and particularly preferably a solution containing 5 to 10% whey protein. The pH of this whey protein is 6
It is preferable to adjust to -9. The degree of heat denaturation of the partially heat-denatured whey protein used in the present invention can be confirmed by measuring the degree of hydrophobicity. Usually, the hydrophobicity (FI / mg protein) defined below is 50 or more, and particularly preferably 100 or more. If it is not more than 50 / mg protein, a partially heated denatured product of whey protein suitable for use in the production of Japanese confectionery of the present invention cannot be obtained.

Hydrophobicity: An aqueous whey protein solution to be tested is diluted to an appropriate concentration (about 0.1 to 0.3 g protein / L),
8 mM 1-anilinonaphthalene-8-sulphonic acid was added as a fluorescent probe, and the excitation wavelength was 3 using a fluorometer.
Measured at 70 nm and emission wavelength of 470 nm (fluorescence amount FI)
The obtained values are shown per whey protein (mg). This heat denaturation measuring method is described in the above-mentioned JP-A-5-6.
It can be carried out according to the description disclosed in Japanese Patent No. 4550.

The partially heated denatured product of whey protein prepared by the above-mentioned method shows about 30 to 95% of protein and 0.5 to 10% of ash content in terms of solid content, but if necessary, starch can be used. It can also be diluted with wheat flour. As a raw material for preparing the whey protein aqueous solution or powder thereof used in the present invention, whey protein concentrate (WPC) or whey protein isolate (WPI) purified from whey obtained in the process of producing cheese or the like from milk. ) Etc. can be mentioned. In particular, WPI has a high degree of purification and is particularly preferable for carrying out the present invention, and is also desirable in terms of flavor.

In the present invention, an aqueous solution containing the above partially-heated denatured whey protein or a dry powder thereof is used alone, or if necessary, it is usually used for imparting water retention and stability to Japanese sweets. It may be mixed with starch or gelling agent. When this solution or its powder is used for the production of Japanese confectionery, it is converted into whey protein in an amount of 1.0 to 10% by weight, particularly preferably 3 to 6% by weight, based on the raw material.
More preferably, 5% by weight is added. In this case, as described above, known additives such as starch and gelling agent may be used in combination. In the production of the Japanese confectionery of the present invention, the aqueous solution obtained by heating the aqueous solution of whey protein as described above may be used directly or may be a dry powder.

The aqueous solution obtained by heat-treating the aqueous solution of whey protein can be pulverized by a drying treatment. The powdering method can be exemplified by a spray drying method, a freeze drying method, a drum drying method and the like. In any method, the powdered whey protein partially heated denatured product used in the present invention can be prepared. You can It was confirmed that the partially heat-denatured product of whey protein produced as described above had a structure distinctly different from that of ordinary whey protein. That is, whey proteins, which are usually spherical, form soluble linear aggregates by partial heat denaturation. This linear aggregate is another name for the above-mentioned soluble aggregate, but the spherical whey protein is partially denatured by heating and has a continuous shape like beads. This is linear due to the delicate balance between the electrostatic repulsive force due to the charge of the protein and the attractive force of the hydrophobic interaction. Since the whey protein in this state has a high hydrophobicity (FI), p
It is more susceptible to H changes and the action of salts. For example,
Examples include neutralization of charges by salts and acidic pH (pH 4 or less). In addition, since free -SH groups in β-lactoglobulin and α-lactalbumin that compose whey proteins are activated, proteins are easily bound to each other via -SH groups. Furthermore, addition of salt or acidification neutralizes the positive charge, reduces electrostatic repulsion, and facilitates protein association.

For the above-mentioned reasons, a reaction with the monovalent or divalent salts used for the production of the Japanese confectionery of the present invention is caused to be organized and viscous, and water is used for gel formation. Further, by incorporating it into the gel, it is possible to obtain a Japanese confectionery which imparts an appropriate viscosity, has a small amount of water separation, and has high water retention and good storage stability. Since the Japanese confectionery prepared by the present invention contains whey protein, it can supply essential amino acids such as lysine and sulfur-containing amino acids, which tend to be deficient, and has a high nutritional effect. In the present invention, a partially heat-denatured whey protein solution or a powdered product thereof is used as a protein at a concentration varying in the range of 3 to 7% by weight, whereby a crispness peculiar to agar gel such as water yokan It is possible to provide Japanese confectioneries in various gel states, from a gel having a good texture to a gel having a highly adherent texture composed of a new flour such as Uiro. Furthermore, by using a high concentration of 7 to 10% by weight, a hard gel such as kneaded yokan can be provided. Further, if the concentration is as low as 1% by weight or less, it can be used as a stabilizer for bean jam.

According to the present invention, the partially heated denatured whey protein is 1.0% by weight or more with respect to the raw material for sweets containing sugar bean paste as a main raw material, and monovalent or divalent salts which are harmless to food hygiene are added to whey protein. And 0.05% by weight or more are added and mixed to form a gel structure, whereby a Japanese confectionery with improved water retention and storage stability can be obtained. By changing the addition amount of this partially heated denatured whey protein and the water content of the product, even an unskilled craftsman can obtain an agar gel-like tissue, a kudzu gel-like tissue, and a Kaminari powder gel-like tissue. Thus, Japanese confectionery containing bean paste as a main component, for example, a kneaded product such as yokan or a Japanese confectionery such as kneaded paste, can be freely prepared. The content of partially heat-denatured whey protein is set to 5% by weight and the addition amount of salt for gelation is changed to freely prepare a water-yokan-like tissue, a yokan-like tissue, and a uiro-like tissue. . In addition, in order to prepare a kneading-like texture, the water content of the raw material is made relatively low, and the amount of partially heat-denatured whey protein added is 1
It should be about%. These structures have good water retention properties and improve the storage stability of Japanese sweets. Also, unlike starches, it does not deteriorate in quality due to aging.

The salt used in the present invention may be either an organic salt or an inorganic salt, as long as it is a monovalent or divalent salt which is generally usable for food hygiene and is generally usable. Such salts include calcium chloride, sodium chloride, magnesium chloride, potassium chloride, calcium sulfate, sodium sulfate, magnesium sulfate, potassium sulfate, sodium monophosphate, sodium diphosphate, sodium polyphosphate, sodium hydrogen carbonate, sodium citrate. , Calcium lactate, sodium tartrate,
Inorganic salts such as sodium ascorbate and organic salts may be used alone or in combination of two or more.
The above salts have a function of cross-linking the partially heat-denatured whey protein with an ionic bond, but if it is too small, it does not exert its effect, and if it is too large, it acts excessively and forms a hard and poorly textured gel. . Generally, it is necessary that the salt concentration is not less than 0.05% by weight based on the whey protein in order to gel an aqueous solution having a partially heated denatured whey protein concentration of 15% or less. Therefore, in order to prepare the Japanese confectionery of the present invention, it is preferable that the salt added to the Japanese confectionery raw material has a concentration of 0.05% or more with respect to whey protein. Depending on the type of Japanese confectionery, there are cases where a certain amount of salt is contained in the raw material, such as salt bean jam.In that case, the amount of salt added to achieve the desired tissue state depends on the content. Need to be reduced.

The salt may be added as a solid as long as it has high dispersibility, but it is preferably used as a 1 to 20 wt% salt aqueous solution. When it is used in a solution, the dispersibility is further increased and partial crosslinking due to insolubility of the salt can be prevented. The desirable concentration of each salt in the raw material is 0.07 to 0.5% by weight for calcium chloride, calcium lactate and magnesium chloride with respect to whey protein, and sodium chloride, potassium chloride, sodium ascorbate and sodium tartrate for whey protein. 0.5-2.0% by weight, sodium monophosphate, sodium diphosphate, sodium polyphosphate 0.8-2.5% by weight, sodium hydrogen carbonate, sodium citrate 0.3-1.
0% by weight. If it deviates from this numerical range, the partially heat-denatured whey protein does not gel or exhibits an extreme gel state, which is not preferable. Further, in the case of a high concentration, some salts have a salty or bitter taste, which is not preferable.

The present invention will be described in more detail with reference to the following examples.

Example 1 In this example, a method for preparing the partially heat-denatured whey protein used in the present invention and a method for preparing this powder will be described. (1) Commercially available whey protein isolate WPI (BIO-I
Product made by SOLATES LTD. BIOPRO) 1
kg was dissolved in deionized water to a total amount of 10 kg (whey protein concentration 10%, pH 7). The mixture was heated with stirring and held for 25 minutes after the liquid temperature reached 85 ° C. Then, it was cooled to 20 ° C. to obtain a heat-denatured whey protein aqueous solution. When the FI value of this aqueous solution was measured according to the above definition, it was 98 / mg protein. This solution was used as a partially heated denaturing aqueous solution of whey protein. 1000 l of the aqueous solution prepared by the above method was spray-dried by a conventional method using a spray-drying device to obtain 8 kg of dry powder. This powder was a fine powder having high water solubility. When this powder was dissolved in water to a concentration of 10% and the FI value was measured, it was 98 / mg protein.

(2) Whey protein isolate (WPI, Taiyo Kagaku KK, Sanlacto I-1, protein content 89.
8%, ash content 1.34%) 200 g deionized water 1800
10 g of WPI solution (protein concentration 9%, ash content 0.13%, pH 7) was prepared. This WPI solution was heated in a hot water bath with stirring and kept for 25 minutes after the liquid temperature reached 80 ° C. Then, cool to 5 ℃ in ice water,
Partially heat-denatured whey protein was obtained. F of this protein
When the I value was measured, it was 95 / mg protein.

(3) Whey protein concentrate WPC (EX
120 g of PRESS FOOD, TYPE 7502, 75% protein, 5% ash) was dissolved in 1880 g of deionized water to prepare a 6% WPC solution (protein concentration 4.5%, ash content 0.3).
%, PH 6.8) was prepared. The WPC solution was heated in a hot water bath with stirring and kept for 5 minutes after the liquid temperature reached 95 ° C. Then, it cooled to 30 degreeC, and it concentrated to 9% solid concentration with the ultrafiltration apparatus (molecular weight fraction 10000). Then, it was heated to 50 ° C., and a whey protein powder denatured by heating with a pressure spray dryer was obtained. 1 of this powder
It was dissolved in water to 0% concentration and the FI value was measured. 83 /
It was mg protein.

[0019]

[Example 2] To 160 parts of unsweetened raw bean jam and 70 parts of sugar, 250 parts of the partially heated denatured whey protein aqueous solution prepared in Example 1 (2) was mixed and mixed well until both were homogeneously mixed. Kneaded. This was then cooled to 20 ° C. or lower, and then 20 parts of an 8 wt% calcium lactate aqueous solution was added with stirring. 80 ml of this solution was filled and sealed in a mold, and allowed to stand overnight at 5 ° C. to obtain a Japanese confectionery having a water-yokan-like texture. On the other hand, as a conventional product, agar yokan was prepared using agar as in the prior art. That is, bean paste 160
2 parts of agar and 268 parts of water were mixed by heating with 70 parts of sugar and 70 parts of sugar, and 80 ml each was filled and sealed in a mold to be solidified. Furthermore, 5 parts of starch was added to this formulation to give a comparative example.

It is said that water yokan is difficult to store for a long period of time. Since it has a high water content, water is separated when it is stored for a long period of time and the quality is remarkably deteriorated. For this reason, canned products are generally used. However, even if such a product is used for a long time, a large amount of water is observed when the can is opened. The product prepared by the above production method was stored, and the amount of free water in the total volume was measured. Figure 1 shows changes in the amount of water separation over time.
In addition, Table 1 shows the results of sensory evaluation by 20 panelists.
It was shown to. The water yokan according to the present invention was able to maintain the quality during production even during long-term storage.

[0021]

[Table 1] ───────────────────────────────── Sensory evaluation results ────────── ─────────────────────── 1st day 2nd day 6th day 8th day 10th day ───────────── ───────────────────── Inventive product Smooth No change No change No change No change Conventional product Smooth No change Brittle shrinkage Roughness Starch-added product Smooth no change Brittle shrinkage Roughness ──────────────────────────────────

[0022]

[Example 3] 400 parts of sweetened bean paste and 70 parts of sugar,
50 parts of the partially heat-denatured whey protein spray-dried product prepared in Example 1 (1) and 476 parts of water were mixed and completely dissolved. To this solution, 4 parts of a 25 wt% calcium chloride solution was added with stirring. Fill the mold with this solution,
The mixture was allowed to stand overnight at 5 ° C to obtain a Japanese confectionery having a texture of kneaded yokan. The product was stored for 30 days or longer, but no tissue change or syneresis was observed.

[0023]

Example 4 350 parts of sweetened white bean paste and 70 parts of sugar were heat treated at 90 ° C. for 10 minutes according to Example 1 (3).
Partially heat-denatured whey protein solution 5 with C 8.5 wt% concentration
50 parts were mixed and completely dissolved. After cooling this solution to 20 ° C. or lower, 40 parts of a 10% sodium dihydrogen phosphate solution was added with stirring. This solution was filled in a mold and allowed to stand at 5 ° C. overnight to obtain a Japanese confectionery having a Uiro texture. The product was stored for 30 days or longer, but no tissue change or syneresis was observed.

[0024]

[Example 5] 400 parts of sweetened bean paste and 70 parts of sugar,
80 parts of a spray-dried product of partially heat-denatured whey protein prepared according to Example 1 (1) was mixed with 410 parts of water,
It was completely dissolved. To this solution, 40 parts of an 8 wt% calcium lactate solution was added with stirring. This solution was filled in a mold and allowed to stand at 5 ° C. overnight to obtain a Japanese confectionery that had a kudzu steamed and youkan-like texture. The product was stored for 30 days or longer, but no tissue change or syneresis was observed.

[0025]

EFFECTS OF THE INVENTION The present invention provides a Japanese confectionery containing bean paste as a main component with improved water retention and stability, and a method for producing the same. In the present invention, the partially heat-denatured whey protein forms a reticulated gel by the added inorganic salts and organic salts. The formed gel has elasticity and water retention, and the properties of the gel can be changed by changing the protein concentration and the salt concentration. When the partially heated denatured whey protein is present in the Japanese confectionery, a gel is formed as a result of the reaction with the inorganic salt and the organic salt, so that the water retention and storage stability of the Japanese confectionery can be improved. Furthermore, by changing the amount of addition depending on the purpose, various partially heat-denatured proteins such as gel-like tissue using agar, kudzu-like gel-like tissue, and gel-like tissue using Kamishinoko are available. It is possible to form Japanese sweets in a gel state. Furthermore, the Japanese confectionery obtained according to the present invention is excellent in preservability because it does not release water.

[Brief description of drawings]

FIG. 1 shows the results of measuring the amount of water separation with time of the water yokan prepared in Example 2.

Claims (7)

[Claims] 1. A partially heated denatured whey protein is contained in an amount of 1% by weight or more and a monovalent or divalent salt is contained in an amount of 0.05% by weight or more based on the whey protein, and the partially heated whey protein is gelled. , Japanese sweets containing bean paste as a main component, which have improved water retention and stability. 2. The partially heat-denatured whey protein is a heat-treated aqueous solution obtained by dissolving substantially desalted whey protein in water at a protein concentration of 15% or less and heat-treating at a temperature of 55 to 120 ° C. The Japanese confectionery according to claim 1. 3. A partially heat-denatured whey protein is substantially desalted, and whey protein is dissolved in water at a protein concentration of 15% or less and heat-treated at a temperature of 55 to 120 ° C. to dry the heat-treated aqueous solution. The Japanese confectionery according to claim 1, which is a powder obtained by 4. The Japanese confectionery according to claim 1, wherein the partially heated denatured whey protein has a hydrophobicity (FI) of 50 / mg protein or more. 5. The monovalent or divalent salt is a potassium salt,
The Japanese confectionery according to claim 1, which is at least one salt selected from the group consisting of sodium salt, calcium salt and magnesium salt. 6. A monovalent or divalent salt is calcium chloride, calcium lactate, magnesium chloride, sodium chloride, potassium chloride, sodium ascorbate, sodium tartrate, sodium monophosphate, sodium diphosphate, sodium polyphosphate, hydrogen carbonate. The Japanese confectionery according to claim 1, which is one or more salts selected from the group consisting of sodium and sodium citrate. 7. A partially heated denatured whey protein of 1 wt% or more and a monovalent or divalent salt of 0.05 wt% or more with respect to whey protein are added and mixed to a Japanese confectionery material containing bean paste as a main component. A method for producing a Japanese confectionery having improved water retention and stability, which comprises gelling a partially heated denatured whey protein.