Chocolate with high soybean saponin content

Abstract

It has been reported that soybean saponin has various physiological activities, but the content thereof in natural products is low, and it is difficult to blend soybean saponin with other materials in terms of flavor and physical properties. In addition, concentrated saponin greatly inhibits flavor. To find out a material highly containing saponin derived from soybean and free from unpleasant bitterness and astringency, and to produce chocolates highly containing saponin by using the material.SOLUTION: It has been found that a hardly soluble soybean protein material, which is an undecomposed residue produced by enzymatically hydrolyzing a soybean protein raw material, contains saponin at a high level and does not have unpleasant bitterness or astringency. By blending the hardly soluble soybean protein material with chocolate, a desired amount of saponin can be contained without affecting flavor and texture.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to chocolates with a high soybean saponin content and a method for producing the same. [Background technology]

[0002] Saponin is a general term for compounds formed by the o-glucoside bond between sapogenin and a sugar. Sapogenin is found in many plants, and is found in large amounts in the roots, stems, and leaves. It is known to be particularly abundant in beans. Approximately 50 or more types of saponins have been found in soybeans, but they are broadly classified into group A saponins and DDMP saponins, mainly based on differences in the structure of the non-sugar portion (called the aglycone) (Non-Patent Document 1). Group A saponins are called bisdesmoside saponins, which have soyasapogenol A as the aglycone and sugar chains attached to the C-3 and C-22 hydroxyl groups, and are the major saponin components detected in soybean seed hypocotyls (Non-Patent Document 1). DDMP saponin has an aglycone structure in which the C-22 hydroxyl group of soyasapogenol B is attached to the C-2 hydroxyl group of DDMP (2,3-dihydro-2,5-dihydroxy-6-methyl-4H-pyran-4-one), and is a monodesmoside saponin in which a sugar chain is glycosidically attached to the C-3 hydroxyl group of the soyasapogenol B residue (Non-Patent Document 1). Soybean saponin has been reported to have various physiological activities (Non-Patent Document 1). For example, it has been reported that soybean saponin has an anti-hyperlipidemic effect by binding to sterols and bile acids in the intestine and inhibiting their absorption. It has also been reported that soybean saponin inhibits colon cancer cell proliferation, and in vitro studies have shown a delay in the division cycle of cancer cells in a human colon cancer cell model. It has been reported that serum lipids such as cholesterol improve when a person takes 200 mg of saponin per day (Non-Patent Document 2).

[0003] Soybean saponin can be ingested from soy foods or as a highly concentrated extract from soybean hypocotyls. The soybean saponin content in soybean food materials is, for example, approximately 0.35% by mass in freeze-dried tofu and approximately 0.4% by mass in yuba, the soybean skin with the highest content (Non-Patent Document 2). Soybean protein isolates can contain as much as 1% by mass. Meanwhile, most soybean saponin is typically extracted from soybean hypocotyls using aqueous ethanol along with soybean isoflavones. For example, Patent Document 1 discloses a method for producing a composition rich in sapogenin, a component of saponin, using a lower alcohol. Furthermore, alcohol is also used in the method for producing soybean saponin shown in Patent Document 2.

[0004] Chocolates, such as chocolate, are widely consumed worldwide due to their pleasant flavor. They are also effective in masking unpleasant flavors, and many chocolates containing various physiologically functional substances are on the market. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 5597136 [Patent Document 2] Japanese Patent Application Publication No. 4-36242 [Non-patent literature]

[0006] [Non-Patent Document 1] Science Forum, Keisuke Kitamura, "All About Soybeans," Chapter 4, Section 8, 1, Soybean Saponin (Tomohiro Tsukamoto) [Non-patent document 2] Chemistry and Biology., 1983, Vol.21, No.4, 224-232. Summary of the Invention [Problem to be solved by the invention]

[0007] As mentioned above, chocolate has a high masking effect on other unpleasant flavors. To add 200 mg of saponin to a 60 g bar of commonly available chocolate, 20 g of soy protein isolate containing 1% saponin by mass would be required, and adding it to 60 g of chocolate would significantly impair the flavor and texture. The same is true for traditional foods such as tofu and yuba. A material containing a high concentration of saponin that has little effect on the flavor and texture when added to chocolate is desired. On the other hand, soy saponin isolated and purified using alcohol or other methods requires a complex and costly process, and even when used in small amounts, it produces an unpleasant bitterness or astringency. The present invention aims to find a material that is rich in soybean-derived saponin and does not have an unpleasant bitter or astringent taste, and to produce chocolates with a high saponin content using this material. [Means for solving the problem]

[0008] Through extensive research, the present inventors have discovered that a poorly soluble soy protein material, which is an unhydrolyzed residue produced by enzymatic hydrolysis of a soy protein raw material, contains a high amount of saponin without having an unpleasant bitter or astringent taste. They have found that by blending this poorly soluble soy protein material with chocolate, it is possible to obtain a desired amount of saponin without affecting the flavor and texture, and have thus completed the present invention.

[0009] That is, the present invention provides: (1) Chocolates characterized by containing 7 to 20% by mass of a hardly soluble soy protein material. (2) Chocolates according to (1), in which the hardly soluble soy protein material is an undecomposed residue produced by enzymatic hydrolysis of a soy protein raw material. (3) Chocolates according to (1) or (2), in which the hardly soluble soy protein material contains soybean saponin in an amount of 2.5% by mass or more in terms of dry matter and has an NSI of 10 to 60%. (4) A method for producing chocolates, including all of the following steps (A) to (C). (A) A process of enzymatically hydrolyzing a soy protein raw material and recovering the resulting unhydrolyzed residue. (B) A step of drying the collected fraction to obtain a poorly soluble soy protein material. (C) A process of preparing a chocolate dough containing a hardly soluble soy protein material, molding it as necessary, and then solidifying it. (5) The method for producing chocolates according to (4), which includes a step of adding the hardly soluble soy protein material to the dough so that the amount of the hardly soluble soy protein material is 7 to 20% by mass. (6) A method for producing a food material for supplying saponin, comprising all of the following steps (A) to (B): (A) A process of enzymatically hydrolyzing a soy protein raw material and recovering the resulting unhydrolyzed residue. (B) A step of drying the collected fraction to obtain a poorly soluble soy protein material, which is a food material for supplying saponin. It is related to. [Effects of the Invention]

[0010] According to the present invention, a saponin-rich food material containing a large amount of soybean saponin and chocolates containing a high saponin content can be easily obtained. The resulting saponin-rich food material and chocolates have a pleasant flavor that is free from either the off-flavor inherent in soybean protein materials or the bitterness inherent in saponin. DETAILED DESCRIPTION OF THE INVENTION

[0011] (Chocolate) The chocolates of the present invention are foods in which fats and oils form a continuous phase and are made using ingredients derived from cacao. One example is chocolates that comply with the "Fair Competition Code and Enforcement Regulations for Chocolate Labeling" established by the National Chocolate Industry Fair Trade Council. These are a general term for chocolate-based foods such as chocolate, semi-chocolate, chocolate confectionery, semi-chocolate confectionery, and chocolate processed products, and preferably refer to foods with a moisture content of 3% by mass or less. Chocolates also include those containing optional auxiliary ingredients such as sugars, milk powders, cacao ingredients (cocoa mass, cocoa, cocoa butter), fruit juice powders, fruit powders, flavoring agents, emulsifiers, flavorings, and coloring agents, blended in any proportion.

[0012] The flavors of chocolates naturally fall within the scope of sweet chocolates, which are primarily composed of cacao ingredients and sugars, milk chocolates and white chocolates, which also contain milk powder as a primary ingredient, as well as a variety of flavors such as coffee, caramel, matcha, fruit, vegetable, and salty flavors.

[0013] (Insoluble soy protein ingredient) The poorly soluble soy protein material of the present invention refers to a protein material derived from soy protein and having low solubility in water. Preferably, the soluble nitrogen index (NSI) described below is 10 to 60%, more preferably 20 to 50%. Furthermore, the TCA solubility rate described below is preferably 1 to 50%, more preferably 10 to 45%. Furthermore, the crude protein content in the dry matter is preferably 50% by mass or more, more preferably 60% by mass or more, and most preferably 65% ​​by mass or more. The crude protein content referred to in the present invention is the crude protein amount obtained by multiplying the nitrogen amount measured by the Kjeldahl method by a nitrogen conversion coefficient of 6.25. Typically, in the industrial production of peptides from soy protein, the undigested residue generated during the protease digestion of soy protein is obtained as a precipitate fraction. Because the main product, peptide, belongs to the low molecular weight fraction, this precipitate fraction is sometimes called "HMF" (High Molecular Weight Fraction), which means the high molecular weight fraction. The production method is explained below with examples.

[0014] (soy protein raw material) Soy protein raw materials are concentrated proteins made from soybeans, and examples include concentrated soy protein and isolated soy protein. The soy protein raw material may be sterilized and dried. Soy protein raw materials preferably contain 80% or more by dry mass of crude protein, with isolated soy protein being preferred. Soy protein isolates are generally prepared by the following method. Specifically, water is added to defatted soybeans, and extraction is carried out at approximately neutral pH. The soy milk is then extracted and the okara is separated to obtain soy milk. The soy milk is then adjusted to approximately pH 4.5, and the isoelectric precipitate is collected. Water and an alkaline agent are added to the precipitate to obtain an aqueous solution with a solids concentration of 5 to 15% by mass and a pH of 5.7 to 8.0, preferably approximately pH 6.8 to 7.5. The soy protein isolate obtained in this manner may be used directly in the subsequent steps, or water may be added to a dried soy protein isolate powder. The soy protein isolate is not limited to the above-mentioned method, and various modifications of the method may also be used. Examples of commercially available soy protein isolates include "Fujipro-R" and "Fujipro-SE" (manufactured by Fuji Oil Co., Ltd.).

[0015] (hydrolysis) Hereinafter, an embodiment of obtaining a hydrolysate and a poorly soluble soy protein material, which is a poorly soluble fraction, from a soy protein raw material by enzymatic hydrolysis will be described. The degree of enzymatic hydrolysis can be appropriately determined for peptides, which are the main products of the degradation process, taking into consideration the properties to be imparted to these peptides. Generally, it is appropriate that not all molecules are degraded to free amino acids, and a higher degree of degradation is preferable. When the degree of degradation is determined based on the yield of the sparingly soluble fraction, this yield is preferably 20 to 35% by mass, and more preferably 25 to 30% by mass. When determining based on the composition of the soluble fraction of the degradation process, the content of peptide fractions with a molecular weight of less than 500 can be, for example, preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 65% ​​by mass or more, based on the total amount of peptides and free amino acids. The content of peptide fractions with a molecular weight of less than 500 is measured as the molecular weight distribution described below.

[0016] The protease used for enzymatic hydrolysis to obtain a soy protein hydrolysate can be appropriately selected from proteases classified as "metalloproteases," "acid proteases," "thiol proteases," and "serine proteases," regardless of whether they are of animal, plant, or microbial origin, and preferably from proteases classified as "metalloproteases," "thiol proteases," and "serine proteases." Furthermore, a method in which two or more types of enzymes belonging to different classes are used in combination, either sequentially or simultaneously, is also efficient and preferred.

[0017] This classification of proteases is based on the type of amino acid at the active center, a method commonly used in the field of enzyme science. Representative examples of each type include "metal proteases" such as Bacillus-derived neutral protease, Streptomyces-derived neutral protease, Aspergillus-derived neutral protease, and thermoase; "acid proteases" such as pepsin, Aspergillus-derived acid protease, and Smithyme FP; "thiol proteases" such as bromelain and papain; and "serine proteases" such as trypsin, chymotrypsin, subtilisin, Streptomyces-derived alkaline protease, alcalase, and bioprase.

[0018] The reaction pH and reaction temperature of the protease treatment may be set according to the characteristics of the protease used, and typically the reaction pH is near the optimum pH, and the reaction temperature is near the optimum temperature. The reaction temperature is generally 20 to 80°C, preferably 40 to 60°C. After the reaction, the mixture is heated to a temperature sufficient to inactivate the enzyme (approximately 60 to 170°C) to inactivate any remaining enzyme activity.

[0019] (Separated drying) From the reaction solution after protease treatment, the insoluble fraction, which is the undigested residue produced by hydrolysis, is recovered by centrifugation or filtration to obtain an insoluble soy protein material. The recovered insoluble soy protein material is usually sterilized and then used in the form of a dry powder obtained by spray drying, freeze drying, etc. Sterilization is preferably by heat sterilization, and the heating temperature is preferably 110 - 170°C, more preferably 130 - 170°C. The heating time is preferably 3 - 20 seconds. Also, the reaction solution may be adjusted to an arbitrary pH. By performing a refinement treatment such as wet grinding before drying, a material with a better texture can also be obtained.

[0020] (Properties of the insoluble soy protein material) The insoluble soy protein material obtained in the steps exemplified above contains group A saponin and DDMP saponin, preferably 2.5% by mass or more, more preferably 3% by mass or more, in the dry matter of the insoluble soy protein material. Another major property of this material is that, although it is a material highly containing saponin, it does not cause deterioration of flavor during ingestion.

[0021] (Method for measuring the soluble nitrogen index) The soluble nitrogen index (NSI) is measured as follows. Add 60 ml of water to 3 g of the protein material sample, stir with a propeller at 37°C for 1 hour, then centrifuge at 1,400×g for 10 minutes, and collect the supernatant (I). Next, add 100 ml of water again to the remaining precipitate, stir with a propeller at 37°C for 1 hour again, then centrifuge and collect the supernatant (II). Combine the (I) liquid and the (II) liquid, add water to the mixed liquid to make it 250 ml. Filter this through filter paper (No. 5), and then measure the nitrogen content in the filtrate by the Kjeldahl method. At the same time, measure the nitrogen amount in the sample by the Kjeldahl method, and NSI is expressed as the ratio of the nitrogen amount recovered as the filtrate (water-soluble nitrogen) to the total nitrogen amount in the sample as a mass%. Basically, it is obtained by rounding off the numerical value of the second digit after the decimal point.

[0022] <TCA solubility rate> An equal volume of 0.44M trichloroacetic acid (TCA) is added to a 2% by mass aqueous solution of protein material to make a 0.22M TCA solution, and the percentage of soluble nitrogen is measured using the Kjeldahl method. This value is generally calculated by rounding off the number to two decimal places.

[0023] <Molecular weight distribution> The method for quantifying the peptide fraction with a molecular weight of less than 500 in peptides and free amino acids is exemplified below as a method for measuring molecular weight distribution. The hydrolyzate was adjusted to a dry matter concentration of 0.1% by mass in the eluent and filtered through a 0.2 μm filter to prepare the sample solution. A gel filtration system was constructed by connecting two columns in series. First, a known protein serving as a molecular weight marker was loaded, and a calibration curve was calculated based on the relationship between molecular weight and retention time. Next, the sample solution was loaded, and the percentage content of each molecular weight fraction was calculated by the ratio of the area of ​​a specific molecular weight range (time range) to the total area of ​​the absorbance chart (1st column: "TSK gel G3000SWXL" (Sigma-Aldrich), 2nd column: "TSK gel G2000SWXL" (Sigma-Aldrich), eluent: 1% SDS + 1.17% NaCl + 50 mM phosphate buffer (pH 7.0), 23°C, flow rate: 0.4 ml / min, detection: UV 220 nm). Generally, values ​​are calculated by rounding to two decimal places. The following markers were used: thyroglobulin, molecular weight: 335,000; γ-globulin, molecular weight: 150,000; albumin, molecular weight: 67,000; peroxidase, molecular weight: 43,000; myoglobin, molecular weight: 18,000; cytochrome C, molecular weight: 12,384; insulin, molecular weight: 5,734; glutathione, molecular weight: 307; and p-amino acid benzoic acid, molecular weight: 137.

[0024] (Chocolate preparation method) The chocolates of the present invention are characterized in that the poorly soluble soy protein material is added in an amount of 7 to 20% by mass in the dough. This amount is preferably 9 to 16% by mass, and more preferably 10 to 14% by mass. The poorly soluble soy protein material contains a high amount of saponin, and even when blended into chocolates in this manner, good flavor quality can be maintained. In particular, within the range of 7 to 20% by mass, the necessary amount of saponin can be ingested by consuming a practical amount of chocolate, while maintaining acceptable flavor properties for chocolates.

[0025] The method for preparing chocolates will now be described. Chocolates can basically be prepared using conventional methods. That is, sugar, cocoa mass, and, if necessary, other raw materials such as fats and oils, are mixed, and then refined (refined) using a roller or the like to prepare a chocolate raw material. Before or after the preparation, a poorly soluble soy protein material or the like is added and mixed to form a chocolate dough. The mixture is then heated and kneaded, molded as necessary, and then solidified to prepare chocolates. As another method, chocolates can also be prepared by adding a poorly soluble soy protein material or the like to a melted chocolate dough prepared in advance, mixing it, molding it as necessary, and then solidifying it. In either method, the poorly soluble soy protein material added is a powder obtained by powder drying or the like, or a material in a highly disintegratable state obtained by freeze-drying or the like. Preferably, these materials are further actively refined using a roller or the like to reduce the roughness of the chocolate and improve its texture. [Example]

[0026] The present invention will be described below with reference to examples, but is not limited to these. In the text, all parts and % are by weight unless otherwise specified.

[0027] (Production Example 1) Preparation of insoluble soy protein material To a 10% by mass aqueous solution of isolated soy protein ("FUJIPRO-R", manufactured by Fuji Oil Co., Ltd.), 0.2% by mass of protease ("PROTIN SD-AY10", manufactured by Amano Enzyme Inc.) was added, and an enzymatic hydrolysis reaction was carried out at 50 °C for 5 hours. After the reaction, it was heated at 100 °C for 5 minutes to inactivate the enzyme and cooled to room temperature. The precipitate was recovered by centrifugation at 8,000 G for 10 minutes to obtain a poorly digestible and poorly soluble soy protein material, the poorly soluble fraction (HMF). The obtained HMF was freeze-dried and then used in the subsequent steps. The yield of the poorly soluble fraction was 28% by mass, the crude protein content in the dry matter was 70.8% by mass, and the fraction with a molecular weight of less than 500 in the soluble fraction (peptides and free amino acids) was 65.4%.

[0028] (Measurement of saponin content) The 2 g test sample was subjected to heating reflux extraction twice with 100 mL of methanol, and the solution filtered through No.5B filter paper was made up to 250 mL. Approximately 3 mL was dried to dryness, heated under reflux for 1 hour with 4 mL of 10% hydrochloric acid methanol, and cooled. 30 mL of water, 40 mL of ethyl acetate, and 1 mL of internal standard substance (cholesterol caprylate - ethyl acetate solution 1 mg / mL) were added, stirred, and 5 mL of saturated sodium hydrogen carbonate solution was added twice to the upper layer, and 10 mL of water was added twice for dehydration to dryness. After adding 2 mL of ethyl acetate, 1 mL was taken, dried to dryness, 200 μL of pyridine and 200 μL of BSTFA [N,O-bis(trimethylsilyl)trifluoroacetamide] were added, held at 50 °C for 20 minutes and then cooled, 4 mL of ethyl acetate was added, and it was subjected to gas chromatography. Soyasapogenol A and soyasapogenol B were used as standard substances, and the total value was taken as the amount of soy saponin. The results are shown in Table 1.

[0029] <GLC analysis conditions> Detector: FID Column: DB-1 (J&W SCIENTIFIC) fused silica 0.53×30 m, film thickness 1.5 μm Temperature: Sample inlet and detector 320 °C Column 200 °C (held for 2 minutes) → 20 °C / min → 300 °C (held for 48 minutes) Carrier gas: Helium 100kPa, Hydrogen 60kPa, Air 50kPa

[0030] Table 1 shows the analytical values ​​of various soybean samples, including insoluble soybean protein material (HMF). A comparison with a commercially available soybean protein isolate ("Fujipro-R," manufactured by Fuji Oil Co., Ltd.), soybean peptide ("Hinute AM," manufactured by Fuji Oil Co., Ltd.), and commercially available freeze-dried tofu (manufactured by Misuzu Corporation) revealed that the saponin content of HMF is highly concentrated, three times that of regular soybean protein isolate material.

[0031] (Table 1) Saponin content in various soybean samples (mass % of dry matter) TIFF2026004225000001.tif52124 (Example 1) Preparation of chocolates with high saponin content 1. According to the formulation in Table 2, 88 parts by mass of chocolate raw material ("Milk Chocolate", manufactured by Fuji Oil Co., Ltd.) was heated to 50 to 53°C and melted. 2. 12 parts by mass of hardly soluble soy protein material (HMF) was added and mixed. 3. After tempering, it was solidified at 4°C. 4. The mixture was left in a room at 20 to 22°C for 3 hours to make chocolates. Since the poorly soluble soy protein material (HMF) contains 3.1% by mass of soy saponin, the present chocolates (Example 1) contain 0.372% by mass (372 mg per 100 g) of soy saponin. By consuming 50 to 60 g, which is the amount of a typical chocolate bar, you can ingest approximately 200 mg of soy saponin.

[0032] (Comparative Examples 1 to 4) Using soybean samples, isolated soy protein ("Fujipro-R"), soy peptide ("Hinute AM"), and koya tofu (manufactured by Misuzu Corporation), we investigated the preparation of chocolates containing 0.372% by mass of soy saponin. However, in the case of isolated soy protein, a blend of 39% by mass would be required, and in the case of soy peptide or koya tofu, a blend of over 100% by mass would be required, neither of which is realistic. Therefore, the amounts of these samples added were set to 12% by mass, the same as for the sparingly soluble soy protein material (HMF) (Example 1), and a concentrated saponin material ("Soy Saponin 80" manufactured by FAP Japan Co., Ltd., saponin content 80.0% by mass) was further added to make up the saponin shortage, resulting in a formulation that achieved 0.372% by mass (Comparative Examples 1 to 4). Freeze-dried tofu was powdered in a mixer and added. A control was also prepared using only chocolate dough containing no soy samples, and this was designated Reference Example 1. These formulations are shown in the upper row of Table 2.

[0033] (Table 2) Chocolate composition and evaluation results TIFF2026004225000002.tif86150

[0034] (evaluation) Each of the obtained chocolate samples was subjected to a sensory evaluation for the following items. Eight panelists well trained in the sensory evaluation of chocolate were selected to taste each sample in a blind test, and the scores for the following items were averaged. Items that received a score of 3 or more were considered to be acceptable. Bitterness 5 points: Chocolate has a pleasant bitterness 4 points: A slight bitterness that is unnatural for chocolate 3 points: Bitter, unnatural taste for chocolate 2 points: There is a lingering bitterness that is unnatural for chocolate. 1 point: There is a strong bitter aftertaste that is unnatural for chocolate. ○Astringency 5 points: No astringency 4 points: Not too bitter 3 points: Slightly bitter 2 points: Unpleasant astringency 1 point: Has a bitter, astringent taste Chocolate flavor 5 points: Very good chocolate flavor 4 points: Good chocolate flavor 3 points: Somewhat good chocolate flavor 2 points: Slightly lacking in chocolate flavor 1 point: Poor chocolate flavor Melts in your mouth 5 points: Melts in your mouth very well 4 points: Melts in the mouth well 3 points: Melts in the mouth fairly well 2 points: Melts in the mouth a little poorly 1 point: Does not melt in the mouth

[0035] The results are shown in the lower part of Table 2. Although Example 1 did not perform as well as Reference Example 1 (control), which did not contain any sample, it passed all sensory evaluation criteria. In contrast, when isolated soy protein was used, the required amount of saponin could not be achieved with this sample alone. Comparative Example 1, in which 12% by mass of isolated soy protein was added and the missing saponin was supplemented with concentrated saponin, tended to have poor melt-in-the-mouth texture and a decrease in bitterness, astringency, and chocolate flavor. Comparative Example 2, in which peptide and concentrated saponin were used in combination, deteriorated not only the melt-in-the-mouth texture but also the flavor, while Comparative Example 3, in which freeze-dried tofu and concentrated saponin were used in combination, deteriorated the melt-in-the-mouth texture. Comparative Example 4, in which concentrated saponin was used alone, had a particularly strong, unpleasant astringency. As described above, only Example 1, which used a poorly soluble soy protein material, contained a sufficient amount of saponin while minimizing the deterioration of flavor properties. [Industrial Applicability]

[0036] According to the present invention, saponin can be easily ingested, and foods and beverages with high saponin content can be widely distributed.

Claims

1. A chocolate containing 7 to 20% by mass of a hardly soluble soy protein material.

2. 2. The chocolate product according to claim 1, wherein the hardly soluble soy protein material is an unhydrolyzed residue produced by enzymatic hydrolysis of a soy protein raw material.

3. 3. The chocolate according to claim 1, wherein the poorly soluble soy protein material contains soybean saponin in an amount of 2.5% by mass or more based on the dry matter and has an NSI of 10 to 60%.

4. A method for producing chocolates, comprising all of the following steps (A) to (C). (A) A step of enzymatically hydrolyzing a soy protein raw material and recovering the resulting unhydrolyzed residue. (B) A step of drying the collected fraction to obtain a poorly soluble soy protein material. (C) A process of preparing a chocolate dough containing a hardly soluble soy protein material, molding it as necessary, and then solidifying it.

5. The method for producing chocolates according to claim 4, further comprising a step of adding the poorly soluble soy protein material to the dough so that the content of the poorly soluble soy protein material is 7 to 20% by mass.

6. A method for producing a food material for supplying saponin, comprising all of the following steps (A) to (B): (A) A step of enzymatically hydrolyzing a soy protein raw material and recovering the resulting unhydrolyzed residue. (B) A step of drying the collected fraction to obtain a poorly soluble soy protein material, which is a food material for supplying saponin.

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