Sweet taste enhancer

Abstract

To provide a sweet taste enhancer capable of enhancing sweet taste in food or beverages without increasing the content of saccharide-based sweet components (such as sucrose, glucose, or fructose) or non-saccharide sweet components, and also to provide a food, beverage, seasoning, or the like which comprises the sweet taste enhancer and the sweet taste of which is enhanced due to the sweet taste-enhancing effect.SOLUTION: A sweet taste enhancer for a food or beverage containing a sweet component comprises ergothioneine as an active ingredient. A food or beverage with enhanced sweet taste can be obtained by incorporating ergothioneine as the sweet taste enhancer.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a sweetening enhancer for food and beverages, and food and beverages such as foods, beverages, or seasonings containing the sweetening enhancer and having enhanced sweetness.

Background Art

[0002] Sweetness is a particularly widely preferred taste among the five basic tastes (bitterness, saltiness, sourness, sweetness, umami), but since it is not as strongly felt as bitterness or saltiness, excessive intake of high-calorie saccharides such as sucrose (table sugar) and glucose (glucose) that are often contained in food and beverages has become a global health problem. Due to such backgrounds and recent health trends, there are strong measures and demands for not over-consuming saccharides. However, simply reducing the amount of sugar such as table sugar in food and beverages has a problem that it affects the taste of the food and beverages and the deliciousness decreases.

[0003] Also, although low-calorie or non-calorie sweeteners have been widely used as sugar substitute sweeteners, food and beverages using these high-intensity sweeteners often have unpleasant bitter tastes or aftertastes, and the sweetness lasts for a long time, so the taste is often inferior in terms of taste quality compared to food and beverages using sugar or the like. Therefore, research and development of sweetening substances that enhance the sweetness of sugar and can maintain the sweetness and original deliciousness of food and beverages even when the amount of sugar substitute sweeteners is minimized or the amount of sugar is reduced has been promoted.

[0004] As such a sweetness enhancer, Patent Document 1 describes methyl anthranilate, and when added to a sucrose-containing food or drink product with a sucrose concentration of 2% by mass in the food or drink product, it has been reported to exhibit a sweetness enhancing effect corresponding to an increase in the sucrose concentration in the food or drink product of 0.4 to 0.6% by mass. Further, Patent Document 2 describes a specific quinoline compound, Patent Document 3 describes 2-(3-benzyloxypropyl)pyridine, and Patent Document 4 describes 1-(2-hydroxyphenyl)-3-(pyridin-4-yl)propan-1-one. However, all of these sweetness enhancers are chemically synthesized substances, and their safety as foods has not been confirmed.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Non-Patent Documents

[0006]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] The problem to be solved by the present invention is to provide a sweetness enhancer that can enhance the sweetness of food and drink products without increasing the content of saccharide-based sweetening components or non-saccharide-based sweetening components, which are sweetening components. Further, it is to provide food and drink products such as foods, beverages, or seasonings that contain the sweetness enhancer and have enhanced sweetness due to the sweetness enhancing effect thereof.

Means for Solving the Problem

[0008] As a result of intensive research on substances that can enhance the sweetness of high-calorie saccharides such as sugar, the present inventors found that ergothioneine, which can only be produced by some microorganisms such as fungi, actinomycetes, and cyanobacteria such as mushrooms and Aspergillus oryzae, when contained in trace amounts in food and drink products containing saccharide-based sweetening components such as sucrose, glucose, or fructose, can enhance the sweetness of the food and drink products. Furthermore, it was found that ergothioneine can also enhance the sweetness of non-saccharide-based sweetening components, leading to the completion of the present invention.

[0009] The present invention relates to a sweetness enhancer described in the following (1) to (3), or a food and drink product described in (4) to (7). (1) A sweetness enhancer containing ergothioneine as an active ingredient. (2) A sweetness enhancer for food and drink products containing saccharide-based sweetening components, containing ergothioneine as an active ingredient. (3) The sweetness enhancer according to (2) above, wherein the saccharide-based sweetening component is one or more selected from the group consisting of saccharides such as sucrose (sugar), glucose (glucose), fructose (fructose), fructose-glucose liquid sugar, oligosaccharides, starch syrup, trehalose, maltose (malt sugar), sugar alcohols such as sorbitol, mannitol, and xylitol. (4) A food and drink product containing saccharide-based sweetening components, characterized in that it contains ergothioneine, which is a sweetness enhancer, in an amount of 0.0001% by weight or more based on the sucrose content, 0.0001% by weight or more based on the glucose content, or 0.0003% by weight or more based on the fructose content, and has enhanced sweetness. (5) The food and drink product according to (4) above, wherein the food and drink product is a food, beverage, or seasoning. (6) The food or drink according to (4) above, wherein the food or drink is soy sauce, mirin, amazake, liquid sugar, prepared soy milk, or milk. (7) The food or drink according to (4) above, which is produced using an ergothioneine-high-producing koji strain.

[0010] The present invention also relates to a sweetness enhancer described in (8) and (9) below, or a food or drink described in (12). (8) A sweetness enhancer for a food or drink containing a non-saccharide sweet component, which contains ergothioneine as an active ingredient. (9) The sweetness enhancer according to (8) above, wherein the non-saccharide sweet component is at least one selected from the group consisting of high-intensity sweeteners such as aspartame, acesulfame potassium, sucralose, stevia, lakanka, stevia, licorice, and sweet amino acids. (10) A food or drink containing a non-saccharide sweet component, characterized in that it contains ergothioneine, which is a sweetness enhancer, in an amount of 0.0005% by weight or more based on the content of the high-intensity sweetener, or 0.0004% by weight or more based on the content of the sweet amino acid, and the sweetness of the food or drink is enhanced.

Advantages of the Invention

[0011] According to the sweetness enhancer of the present invention, with the addition of an extremely small amount, it is possible to extract sweetness while reducing the content of the sweet component in the food or drink, so that the sweetness can be enhanced naturally without impairing the flavor. In addition, if food or drink such as seasonings, foods, and beverages to which this is added are consumed, the intake of saccharides can be reduced, and excessive sugar intake can be prevented.

Embodiments for Carrying Out the Invention

[0012] The present invention relates to a sweetness enhancer for a food or drink containing a saccharide sweet component and / or a non-saccharide sweet component, which contains ergothioneine as an active ingredient, and a food or drink with enhanced sweetness containing ergothioneine, which is a sweetness enhancer. In the present invention, “%” means “% by weight” even if the unit is not specified, and 1 ppm is 0.0001% by weight.

[0013] Ergothioneine (hereinafter also referred to as "ERG") was discovered as a sulfur-containing amino acid isolated from Claviceps purpurea and has been confirmed to exist in the living bodies of plants and animals. However, plants and animals cannot synthesize ergothioneine, and the ergothioneine in the living body is considered to be derived from ergothioneine synthesized by microorganisms such as basidiomycetes. It is contained in some mushrooms of basidiomycetes, for example, edible mushrooms such as shiitake mushroom, enoki mushroom, maitake mushroom, and king oyster mushroom, and is particularly known to be abundant in turkey tail mushroom. It is also known that Aspergillus oryzae produces ERG.

[0014] The biosynthetic pathway of ERG from histidine is known in microorganisms, and the sulfur atom is supplied from cysteine. ERG has high antioxidant properties, and its elastase inhibitory effect and tyrosinase inhibitory effect have been reported, and it has attracted particular attention in the fields of beauty and food such as whitening and wrinkle prevention. In addition, it has been found that ERG is involved in the body's antioxidant defense system, and its application in the medical field has also been attempted. ERG has high thermal stability and pH stability, can maintain its antioxidant effect even at high temperatures, and is expected to be used as an antioxidant in addition to being formulated into foods in anticipation of its physiological effects.

[0015] As methods for producing ERG, extraction from basidiomycetes such as turkey tail mushroom, chemical synthesis, and fermentation using microorganisms are being carried out. Extraction from basidiomycetes such as turkey tail mushroom takes time to obtain raw materials and is not suitable for mass production. Chemical synthesis is suitable for mass production, but it is necessary to use expensive synthetic reagents. Therefore, research on production methods by fermentation such as fermentation using C1 compound-assimilating bacteria or yeast, fermentation using microorganisms overexpressing the ERG biosynthetic gene (Patent Document 5), and solid culture using Aspergillus oryzae into which the ERG biosynthetic gene has been introduced to overexpress ERG (Non-Patent Document 1) is being advanced.

[0016] In the sweet taste enhancer of the present invention, commercially available ERG obtained by chemical synthesis may be used, or extracts or purified products thereof from mushrooms containing ERG, Aspergillus koji that produces ERG and its culture, or sake lees produced using Aspergillus koji may also be used. Further, for food and drink products using Aspergillus koji as a raw material, without adding ERG, by using Aspergillus koji that highly produces ERG, the amount of ERG in the food and drink product can be increased to enhance the sweet taste. Examples of the mushrooms used for extracting ERG include Pleurotus cornucopiae var.citrinopileatus, Pleurotus ostreatus, Lentinula edodes, Grifola Frondosa, etc. of the genus Pleurotus of the family Pleurotaceae, which can be preferably listed in descending order of ERG content, and one or more of these can be used in combination.

[0017] As the Aspergillus koji that produces ERG, any fungus belonging to the genus Aspergillus can be used. As an example, Aspergillus oryzae, Aspergillus sojae, Aspergillus niger, Aspergillus luchuensis, Aspergillus tamarii can be mentioned. As the strain of Aspergillus koji, for example, strains available from depository institutions such as Aspergillus oryzae RIB326 strain, strains contained in commercially available seed koji, or strains obtained by isolation from food and drink production environments such as sake breweries and soy sauce brewing cellars can be used.

[0018] In addition to the above wild strain, as the Aspergillus koji that produces ergosterol (ERG), mutant strains with high ERG production can be isolated and used by using common mutagenesis methods. Examples of mutagenesis methods include irradiation with ultraviolet rays (UV) or X-rays that physically damage DNA to introduce mutations, and treatment with alkylating agents such as N-methyl-N'-nitro-N-nitrosoguanidine (NTG) or ethyl methanesulfonate (EMS) that chemically damage DNA to introduce mutations.

[0019] Furthermore, an Aspergillus koji strain with high ERG production into which a gene related to ERG biosynthesis has been introduced by gene recombination can be used. For example, an Aspergillus oryzae mutant strain into which the egtA gene has been introduced (see Patent Document 6 and Non-Patent Document 1), or an Aspergillus-specific AO090005000664 gene (encoded amino acid sequence: SEQ ID NO: 1) into which a G428S mutation or a C459F mutation has been introduced, or a specific gene mutation such as deletion of 1 to 112 amino acids in the region of W404 to Q515, and its ortholog gene have been introduced to increase the expression of ERG (see PCT / JP2023 / 020131), etc., but not limited thereto.

[0020] In this specification, the Aspergillus koji strain with high ERG production refers to a strain in which the produced ERG is 5 to 10 times or more, preferably 20 times or more, compared to a strain that has not mutated or been transformed, in liquid culture at 20 to 30°C for 3 to 14 days (the liquid medium is 5% Perfum SM (manufactured by Kikkoman Corporation) medium, without pH adjustment). For example, an Aspergillus sojae strain in which the above egtA gene is forcibly expressed, or an Aspergillus oryzae mutant strain containing an amino acid mutation or amino acid deletion in the region of W404 to Q515 of the above mutant AO090005000664 gene and its ortholog gene corresponds thereto.

[0021] In addition, when food and drink products use koji mold fermented products as raw materials, such as soy sauce, sake, amazake, mirin, miso, etc., even without adding ERG during production, by using an ERG-high-producing koji mold strain for koji making, the ERG content in the food and drink products can be increased. In particular, when using an ERG-high-producing koji mold strain for the production of fermented foods, fermented beverages, and fermented seasonings, it exhibits effects other than sweetness enhancement compared to the case where ERG is added.

[0022] The saccharide-based sweetening components of the present invention include sucrose (table sugar), glucose (grape sugar), fructose (fruit sugar), fructose-glucose liquid sugar, oligosaccharides, starch syrup, trehalose, maltose (malt sugar), sugar alcohols such as sorbitol, mannitol, xylitol, maple syrup, or honey, etc. In addition, the non-saccharide-based sweetening components of the present invention include high-intensity sweeteners such as acesulfame potassium, aspartame, sucralose, stevia, lacanca, licorice (glycyrrhiza), and sweet-tasting amino acids such as glycine (Gly), alanine (Ala), threonine (Thr), serine (Ser), lysine (Lys), proline (Pro), etc. The food and drink products of the present invention contain one or more saccharide-based sweetening components and / or one or more non-saccharide-based sweetening components.

[0023] The enhancement of sweetness means that the sweetness caused by these is felt stronger compared to the case without the sweetness enhancer of the present invention. Specifically, it means that even if the amount of table sugar, etc. is reduced by 1 to 50% by adding the sweetness enhancer, the same sweetness can be felt. Also, it means that even if the amount of table sugar, etc. is 1.1 to 2 times the original amount, the same sweetness can be felt by adding the sweetness enhancer. Or, when a small amount of table sugar, etc. is contained but not felt, it means that the sweetness can be felt for the first time by adding the sweetness enhancer.

[0024] The amount of ERG that has a sweetening enhancing effect on the sucrose content of food and drink products is 0.01% by weight or more of ERG for a sucrose solution of 0.5% or more and less than 1%, 0.0025% by weight or more for a sucrose solution of 1% or more and less than 10%, and 0.0001% by weight or more for a sucrose solution of 10% or more. Since almost no sweetness is felt in food and drink products with a sucrose content of less than 1%, generally, by containing 0.0001% by weight or more, or 0.0025% by weight or more of ERG with respect to the sucrose content, the sweetening enhancing effect of food and drink products can be exhibited. Thus, the sweetening enhancer of the present invention exhibits the sweetening enhancing effect of food and drink products by containing 0.0001% by weight or more, preferably 0.0025% by weight or more of ERG with respect to the sucrose content in food and drink products.

[0025] Also, for food and drink products containing glucose or fructose, by containing 0.0001% by weight or more, preferably 0.0005% by weight or more of ERG with respect to the glucose content, and by containing 0.0003% by weight or more of ERG with respect to the fructose content, the sweetening enhancing effect of food and drink products can be exhibited. When a food and drink product contains any one or more of sucrose, glucose, or fructose, 0.0001 to 0.0003% by weight or more of ERG may be contained with respect to any of the contents.

[0026] The sweetening enhancer of the present invention exhibits the sweetening enhancing effect of food and drink products by containing 0.0005% by weight or more of ERG with respect to the aspartame content in food and drink products. Also, for food and drink products containing stevia, by containing 0.05% by weight or more of ERG with respect to the stevia content, and by containing 0.0004% by weight or more of ERG with respect to the content of sweet amino acids, the sweetening enhancing effect of food and drink products can be exhibited. When a food and drink product contains a non-saccharide sweet component, 0.0004 to 0.0005% by weight or more of ERG may be contained with respect to a non-saccharide sweet component other than stevia.

[0027] In addition, since the sweetening effect does not increase even when a large amount of the sweetening enhancer of the present invention is contained, considering economic efficiency, ERG can be contained in food and drink products at 0.15% by weight or less, for example 0.12 or 0.09% by weight or less, 0.06 or 0.03% by weight or less. With respect to the content of the sweet component in food and drink products, ERG can be contained at 15% by weight or less, for example 12 or 9% by weight or less, 6 or 3% by weight or less.

[0028] Note that the concentration of ERG is measured by LCMS under the following conditions. (HPLC conditions) HPLC analysis is performed under the following conditions. Apparatus: HPLC apparatus: HPLC: Nexera series (manufactured by Shimadzu Corporation) Column: COSMOSIL 2.5HILIC column 3.0×150 2.5μm 3.0 mm I.D.×15.0 cm (manufactured by Nacalai) Flow rate: 0.5 mL / min Temperature: 40°C Mobile phase: A) 0.1% (v / v) aqueous formic acid solution, B) 0.1 (v / v) formic acid acetonitrile Isocratic: 0 - 10 minutes (B: 80%) Injection volume: 5 μL (Mass spectrometry) Apparatus: LCMS - 2020 (manufactured by Shimadzu Corporation) (Mass spectrometry (LC - MS) analysis conditions) Ionization conditions: ESI+ MS conditions: SIM ERG: m / z230.1([M + H] + ) Retention time: around 5 minutes

[0029] Food and drink products containing the saccharide - based sweet component and / or non - saccharide - based sweet component of the present invention are foods, beverages, or seasonings. The food can be used in all foods and is not limited. For example, frozen desserts such as ice cream and sherbet, desserts such as jelly, pudding, and yokan, dairy products or dairy product substitutes such as yogurt, cheese, and whipped cream, spreads such as nut butter, baked confectioneries such as cookies, biscuits, and cakes, confectioneries such as chocolate, chewing gum, and steamed buns, breads such as sweet bread and table bread, jams, ramune, tablets, lozenges, mycoprotein, pet food, medical foods, etc. are exemplified.

[0030] Beverages are also not limited. For example, soft drinks, milk beverages, soup for beverages such as canned soup, soy milk beverages such as prepared soy milk, sports drinks, fruit juice beverages, alcoholic beverages such as Japanese sake, shochu, and cocktails, amazake which is a rice saccharide, black tea, coffee, green tea, cocoa, nutritional drinks for quasi-drugs, etc. are exemplified. Not only liquid ones but also gel-like and semi-solid ones such as jelly beverages are included. Seasonings are also not limited. Examples include soy sauce, mirin, miso, cooking wine, sauce, soup stock, dashi such as bonito stock, sushi vinegar, sauce, ketchup, liquid sugar, syrup, etc.

[0031] Also, in the process of manufacturing food and beverages, when adding the sweetening enhancer of the present invention to food and beverages, the addition time may be added in any process, and as long as the necessary amount is contained in the final food and beverage product, the addition method is also not limited.

Examples

[0032] Hereinafter, the details of the present invention will be specifically described by showing examples, but the present invention is not limited thereto. In addition, when simply described as “%” in the examples, it means “% by weight”. Also, room temperature samples were used for the sensory evaluation.

[0033] [Test 1: Sweetening enhancement effect of sucrose solution by ERG] Sucrose was added to pure water to prepare six sucrose samples with concentrations of 0%, 1%, 1.5%, 2%, 2.5%, and 3%, and as the seventh sample, a sample prepared by adding purified ergothioneine (purity 99.5% or higher, from Tetrahedron) to 2% sucrose to a final concentration of 60 ppm was prepared. The sweetness was sensory evaluated by a professional panel of five trained sweetness-sensitive subjects. For the five professional panels, regarding the sweetness of the seventh 60 ppm ERG-added 2% sucrose sample, they were asked to select a sample with equivalent sweetness from among the first to sixth sucrose samples (the concentrations were not disclosed to the panel). After tasting each sample and before tasting the next sample, the mouth was thoroughly rinsed with water at room temperature. The results showed that all five panelists evaluated the seventh ERG-added 2% sucrose sample to have the same sweetness as a 2.5% sucrose solution. The addition of 60 ppm of ERG made the sweetness of the 2% sucrose solution equivalent to that of a 2.5% sucrose solution, confirming the sweetness-enhancing effect of ERG.

[0034] [Test 2: Confirmation of the Sweetness of ERG Itself] Similar to Test 1, six sucrose samples with concentrations of 0%, 1%, 1.5%, 2%, 2.5%, and 3% were prepared, and as the seventh sample, a sample prepared by adding ergothioneine to water to a final concentration of 60 ppm was prepared. A drinking test was conducted by the same five professional panels as in Test 1. After tasting each sample and before tasting the next sample, the mouth was thoroughly rinsed with water at room temperature, and the sweetness was sensory evaluated. For the five professional panels, regarding the sweetness of the seventh sample, they were asked to select a sample with equivalent sweetness from among the first to sixth sucrose samples (the concentrations were not disclosed to the panel). The results showed that all five panelists evaluated the seventh sample (prepared by adding ERG to water to a final concentration of 60 ppm) to have the same sweetness as a 0% sucrose solution, confirming that ERG itself has no sweetness.

[0035] [Test 3: ERG Addition Amount That Enhances the Sweetness of Sucrose] (1) In the case of 1 - 50% sucrose samples Samples were prepared by adding ergothioneine to a 1 - 50% sucrose solution so that the final concentrations were 0 ppm, 0.05 ppm, 0.1 ppm, 0.25 ppm, and 0.5 ppm (ERG0 - 0.5 in Table 1 below; hereinafter, "ERGX" means a sample with X ppm of ERG added).

Table 1

[0036] For 1 - 50% sucrose samples (the concentrations are not disclosed to the panel) with ERG added at each concentration, a drinking test was conducted by four expert panels different from Tests 1 and 2, with a 1 - 50% sucrose sample without ergothioneine added as a control, and the sweetness was sensory - evaluated. After tasting each sample and before tasting the next sample, the mouth was thoroughly rinsed with water at room temperature. Pairs combining the control 1 - 50% sucrose sample and 1 - 50% sucrose samples with ergothioneine added at each concentration were presented to the expert panels, and the panels evaluated which of the presented pair of samples tasted sweeter through a two - point discrimination test. The evaluation results are shown in Table 2.

[0037] <Evaluation method of two - point discrimination test> Evaluation results of the sweetness of the test product compared with the control 〇: The sweetness is enhanced compared with the control. ◇: The sweetness is the same as the control. Note that the evaluation method and display of the evaluation results of the two - point discrimination test are the same for other tests.

[0038]

Table 2

[0039] Table 2 shows the evaluation results of the two - point discrimination test by four expert panels A - D and indicates the lower limit of the ERG concentration for the sweetness - enhancing effect on the 1 - 50% sucrose solution. In a sucrose solution of more than 0.5% and less than 1%, when ergothioneine (ERG) was added at 0.5 ppm or more, all the subjects evaluated that the sweetness was enhanced. In a sucrose solution of 1% or more and less than 10%, when ERG was added at 0.25 ppm or more, all the subjects evaluated that the sweetness was enhanced. In a sucrose solution of 10% or more, when ERG was added at 0.1 ppm or more, all the subjects evaluated that the sweetness was enhanced. The amount of ERG that has a sweetness enhancing effect on the sucrose content of food and drink is equivalent to 0.01% by weight or more of ERG in a sucrose solution of more than 0.5% and less than 1%, 0.0025% by weight or more in a sucrose solution of 1% or more and less than 10%, and 0.0001% by weight or more in a sucrose solution of 10% or more.

[0040] (2) In the case of the 4% sucrose sample Samples (ERG 5 - 900) were prepared by adding ergothioneine to a 4% sucrose solution so that the final concentrations were 5 ppm, 20 ppm, 60 ppm, 100 ppm, 400 ppm, and 900 ppm. For the 4% sucrose samples (the concentrations were not disclosed to the panel) with ERG added at each concentration, a drinking test was conducted by 4 professional panels different from Tests 1 and 2, and the sweetness was sensory evaluated. Pairs combining the control 4% sucrose sample in Table 3 below and the 4% sucrose samples with ergothioneine added at each concentration were presented to the professional panel, and the panel evaluated which of the presented pairs of samples tasted sweeter by a two - point discrimination test.

[0041]

Table 3

[0042] Table 3 shows the ERG concentration at which the sweetness enhancing effect on 4% sucrose becomes constant. Since the 4% sucrose sample with 400 ppm of ERG added had the same degree of sweetness as the one with 100 ppm of ERG added, it was evaluated that even if more than 100 ppm of ERG was added, the degree of sweetness enhancement did not change compared to the one with 100 ppm of ERG added, and it was confirmed that the sweetness enhancing effect became constant at 100 ppm of ERG. From the above, in the case of a 4% scroll solution, when ERG was added at 5 ppm to 100 ppm, it was evaluated that as the addition amount increased, the sweetness was sequentially enhanced. When it exceeded 100 ppm, the sweetness enhancement effect was the same as that in the case of adding 100 ppm.

[0043] [Test 4: Upper limit of ERG addition amount] It was dissolved in water at 40 °C so that the ergothioneine concentration became 10% (100,000 ppm), and then left standing at 4 °C. When the solution was checked after 1 day, ERG had precipitated. From the above, the concentration at which ERG can be contained in water is less than 10%.

[0044] [Test 5: Sweetness enhancement effect of glucose solution by ERG] Glucose was added to pure water to prepare six glucose samples with concentrations of 0%, 13%, 14%, 15%, 16%, and 17%, and as the seventh sample, a sample in which ergothioneine was added to 15% glucose so that the final concentration became 60 ppm. The sweetness was sensory evaluated by a professional panel of the same five trained sweetness-sensitive subjects as in Test 1. For the five professional panels, regarding the sweetness of the seventh 60 ppm ERG-added 15% glucose sample, samples with equivalent sweetness were selected from the first to sixth glucose samples (the concentrations were not disclosed to the panel). The results were that among the five panels, three evaluated the seventh ERG-added 15% glucose sample as having the same sweetness as a 16% glucose solution, and two evaluated it as having the same sweetness as a 17% glucose solution. By adding 60 ppm of ERG, the sweetness of the 15% glucose solution became equivalent to that of a 16% glucose solution, and the sweetness enhancement effect of ERG on glucose was confirmed.

[0045] [Test 6: ERG addition amount to enhance the sweetness of glucose] (1) In the case of a 50% glucose sample To the 50% glucose sample, ergothioneine was added at final concentrations of 0.5 ppm, 1 ppm, 3 ppm, 5 ppm, 10 ppm, 20 ppm, 60 ppm, 100 ppm, 400 ppm, and 900 ppm to prepare samples ERG0 - 900 (Table 4).

Table 4

[0046] Four professional panels were presented with pairs combining a control 50% glucose sample without added ergothioneine and 50% glucose samples with ergothioneine added at each concentration. The panels evaluated which of the presented samples tasted sweeter through a two - point discrimination test. The results are shown in Table 5.

[0047]

Table 5

[0048] Table 5 shows the lower limit of the ERG concentration for the sweet - taste enhancement effect on the 50% glucose solution. In the 50% glucose solution, when ERG was added at 0.5 ppm or more, all the panels evaluated that the sweetness was enhanced. This corresponds to ERG having a sweet - taste enhancement effect at 0.0001 wt% or more relative to the glucose content of food and beverages.

[0049] (2) In the case of the 10% glucose solution The same test as in the 50% glucose solution in (1) above was carried out on the 10% glucose solution using the samples (ERG0 - 20) shown in Table 6. The results of the sensory evaluation by the two - point discrimination test are shown in Tables 7 and 8.

Table 6

[0050]

Table 7

[0051] Table 7 shows the lower limit of the ERG concentration for the sweetening effect on a 10% glucose solution. In the 10% glucose solution, when ERG was added at 0.5 ppm or more, all panelists evaluated that the sweetness was enhanced. For the glucose content of food and drink, ERG having a sweetening effect is equivalent to 0.0005% by weight or more.

[0052] [Table 8]

[0053] Table 8 shows the ERG concentration at which the sweetening effect on a 10% glucose solution becomes constant. Since the 10% glucose sample with 100 ppm of ERG added had the same degree of sweetness as the one with 60 ppm of ERG added, it was evaluated that even when ERG was added in excess of 60 ppm, the degree of sweetening enhancement did not change from that with 60 ppm added, and it was confirmed that the sweetening effect became constant at 60 ppm of ERG. From the above, in the 10% glucose solution, when ERG was added at 0.5 ppm to 60 ppm, it was evaluated that the sweetness was sequentially enhanced as the addition amount increased. When it exceeded 60 ppm, the sweetening effect did not change from the case of adding 60 ppm.

[0054] [Test 7: Sweetening effect of ergothioneine on fructose solution] Fructose was added to pure water to prepare six fructose samples with concentrations of 0%, 4.5%, 5%, 5.25%, 5.5%, and 6%, and as the seventh sample, a sample in which ergothioneine was added to 5% fructose so that the final concentration became 60 ppm. The sweetness was sensory evaluated by a professional panel of five trained sweetness-sensitive subjects who were the same as those in Test 1. For the five professional panels, regarding the sweetness of the seventh 5% fructose sample with 60 ppm of ERG added, samples having the same sweetness were selected from among the first to sixth fructose samples (the concentrations were not disclosed to the panel). As a result, three out of five panelists evaluated the seventh sample as having the same sweetness as a 5.5% fructose solution, and two panelists evaluated it as having the sweetness of a 5.25% fructose solution. With the addition of 60 ppm of ERG, the sweetness of the 5% fructose solution became equivalent to that of a 5.25 - 5.5% fructose solution, and the sweetening effect of ERG on fructose was confirmed.

[0055] [Test 8: ERG addition amount enhancing the sweetness of fructose] Samples ((ERG0 - 10)) were prepared by adding ergothioneine to a 20% fructose sample to final concentrations of 0.5 ppm, 1 ppm, 3 ppm, 5 ppm, and 10 ppm. For 20% fructose samples with ERG added at each concentration (the concentration was not disclosed to the panel), a drinking test was conducted by four professional panels using a 20% fructose sample without ergothioneine as a control, and the sweetness was sensory - evaluated. The evaluation results are shown in Table 9. Also, samples (ERG0.5 - 900) were prepared by adding ergothioneine to a 20% fructose sample to final concentrations of 0.5 ppm, 5 ppm, 10 ppm, 20 ppm, 40 ppm, 60 ppm, 80 ppm, 100 ppm, 200 ppm, 400 ppm, and 900 ppm. Pairs of 20% fructose samples with different sequential concentrations of ERG added (for example, pairs of ERG20 ppm and 40 ppm) were presented to professional panels, and the panels evaluated which of the presented samples tasted sweeter through a two - alternative forced - choice test. The evaluation results are shown in Table 10.

[0056]

Table 9

[0057]

Table 10

[0058] For the 20% fructose sample with 0.5 ppm or more of ERG added, all panelists evaluated that the sweetness was enhanced. ERG having a sweetness enhancement effect is equivalent to 0.0003% by weight or more based on the fructose content of the food or drink product. In addition, since the 20% fructose sample with 100 ppm of ERG added was evaluated to have the same degree of sweetness as the one with 80 ppm of ERG added, it was confirmed that even when ERG is added in excess of 80 ppm, the degree of sweetness enhancement remains the same as that with 80 ppm added, and the sweetness enhancement effect becomes constant at 80 ppm of ERG. From the above, in the 20% fructose solution, when 0.5 ppm to 80 ppm of ERG was added, it was evaluated that the sweetness was sequentially enhanced as the addition amount increased. When it exceeded 80 ppm, the sweetness enhancement effect was the same as that with 80 ppm added.

[0059] [Test 9: Addition amounts for enhancing the sweetness of various sweet components of ERG] The following Test 9 was the same two - point discrimination test as Tests 3, 5, and 7, and a sensory evaluation was conducted by three professional panels. (1) Trehalose Samples were prepared by adding ergothioneine to the 50% trehalose sample so that the final concentrations were 0.5 ppm, 1 ppm, 3 ppm, 5 ppm, 10 ppm, and 20 ppm (Table 11, ERG0 - 20).

Table 11

[0060] For the 50% trehalose samples with ERG added at each concentration (the concentration was not disclosed to the panel), pairs combining the control 50% trehalose sample and the 50% trehalose samples with ergothioneine added at each concentration were presented to the professional panel, and the panel evaluated which sample in the presented pairs felt sweeter through a two - point discrimination test. The test results are shown in Table 12.

Table 12

[0061] (2) Fructose glucose liquid sugar A 50% liquid sugar sample of isomerized sugar (New Fructose 55 (NF55), Showa Sangyo Co., Ltd.) containing 55% or more of fructose was added with ERG concentrations (ERG0 to 20) shown in Table 13 to prepare samples. A pair combining a control 50% liquid sugar sample and a 50% liquid sugar sample with ERG added at each concentration was presented, and the panel evaluated which of the presented samples tasted sweet by a two-point discrimination test. The test results are shown in Table 13.

[0062]

Table 13

[0063] (3) Highly saccharified reduced maltose (sugar alcohol) A 50% maltose sample of highly saccharified reduced maltose (ES-600, Product Food Science Co., Ltd.) containing a large amount of monosaccharide alcohol and disaccharide alcohol was added with ERG concentrations (ERG0 to 10) shown in Table 14 to prepare samples. A pair combining a control 50% maltose sample and a 50% maltose sample with ERG added at each concentration was presented, and the panel evaluated which of the presented samples tasted sweet by a two-point discrimination test. The test results are shown in Table 14.

[0064]

Table 14

[0065] (4) Oligosaccharide A 50% oligosaccharide sample (Fujio Oligo #450, Nippon Food Chemical Co., Ltd.) was prepared by adding ERG at the concentrations shown in Table 15 (ERG0 - 10). Pairs were presented consisting of a control 50% oligosaccharide sample and 50% oligosaccharide samples with ERG added at each concentration. The panel evaluated which of the presented samples tasted sweeter using a two - point discrimination test. The test results are shown in Table 15.

[0066]

Table 15

[0067] (5) Aspartame A 10% aspartame sample (Pulse Sweet Slim Up Sugar, Ajinomoto Co., Inc.) was prepared by adding ERG at the concentrations shown in Table 16 (ERG0 - 20). Pairs were presented consisting of a control 10% aspartame sample and 10% aspartame samples with ERG added at each concentration. The panel evaluated which of the presented samples tasted sweeter using a two - point discrimination test. The test results are shown in Table 16.

[0068]

Table 16

[0069] (6) Stevia A 0.1% stevia sample was prepared by adding ERG at the concentrations shown in Table 17 (ERG0 - 20). Pairs were presented that combined a control 0.1% stevia sample and 0.1% stevia samples with added ERG at each concentration. The panel evaluated which of the presented samples tasted sweeter using a two - point discrimination test. The test results are shown in Table 17.

[0070]

Table 17

[0071] (7) Amino acid (glycine) A 12.5% glycine sample was prepared by adding ERG at the concentrations shown in Table 18 (ERG0 - 10). Pairs were presented that combined a control 12.5% glycine sample and 12.5% glycine samples with added ERG at each concentration. The panel evaluated which of the presented samples tasted sweeter using a two - point discrimination test. The test results are shown in Table 18.

[0072]

Table 18

[0073] [Test 10: Sweetness - enhancing effect of sweet rice wine] Production of sweet rice wine 1,250 g of white rice was soaked overnight, transferred to a colander, and drained for 2 hours. Then it was wrapped in a Tetoron cloth and steamed at 100°C for 40 minutes. The steamed rice was cooled to 45°C and inoculated with koji spores. It was wrapped in a Pyren cloth and koji making was started under the conditions of 35°C and 95% humidity. Nineteen hours after the start of koji making, the koji rice was loosened and wrapped again with a Pyren cloth. When the product temperature reached 40°C, the Pyren cloth was spread out to flatten the koji rice. After another 40 hours, the koji rice was loosened well and left standing again. Koji was taken out after 42 hours. 2.5 times the amount of 60°C hot water was added to 800 g of the obtained koji rice, and a saccharification reaction was carried out at 55°C and 200 rpm. After 16 hours, the Brix was adjusted to 18% and transferred to a heat-resistant container, and sterilized at 85°C for 30 minutes. When preparing the Brix of amazake, water or ergothioneine was added to prepare amazake with ergothioneine concentrations in amazake of 12 ppm (with water added), 30 ppm, 45 ppm, 80 ppm, 145 ppm, and 345 ppm.

[0074] The sweetness of amazake was sensory evaluated by a professional panel of 5 trained sweetness sensitivity subjects. Five professional panels were presented with pairs of amazake containing different concentrations of ERG (ERG12 - 345) shown in Table 19, and the panelists evaluated which of the presented samples tasted sweet by a two-alternative forced-choice test. The results are shown in Table 19. Amazake prepared with ERG of 30 ppm or more was evaluated by all panelists as having enhanced sweetness. Amazake prepared with ERG of 345 ppm was evaluated by a majority of the panelists as having the same degree of sweetness as amazake prepared with ERG of 145 ppm, and the degree of sweetness enhancement was not different from that with 145 ppm added. In amazake, when containing 30 ppm - 145 ppm of ERG, it was evaluated that the sweetness was sequentially enhanced as the content increased. Even when exceeding 145 ppm, the sweetness enhancement effect was not different from the case of adding 145 ppm.

[0075]

Table 19

[0076] [Test 11: Sweetness Enhancement Effect of Mirin] Commercially available mirin (ergothioneine content 1.6 ppm) was heated to remove alcohol, and mirin was prepared by adding ergothioneine to this so that the final concentration of ergothioneine became 1.6 ppm, 2.1 ppm, 4.6 ppm, 6.6 ppm, 11.6 ppm, 21.6 ppm (ERG1.6 - 21.6). Regarding the mirin added with ERG at each concentration (the concentration was not disclosed to the panel), a drinking test was conducted by three professional panels using mirin without added ergothioneine (ERG1.6) as a control, and the sweetness was sensory evaluated. Pairs combining the control mirin and the mirin added with ergothioneine at each concentration were presented to the professional panel, and the panel evaluated which of the presented samples felt sweeter by a two - point discrimination test. The results are shown in Table 20.

[0077] [Table 20] Not only the 2.1 ppm mirin added with 0.5 ppm ERG, but also the mirin containing 4.6 - 21.6 ppm ERG was evaluated by all panelists as having enhanced sweetness.

[0078] [Test 12: Sweetness Enhancement Effect of Soy Sauce] (1) Special - selected round - soybean soy sauce Soy sauce was prepared by adding ergothioneine to commercially available special - selected round - soybean soy sauce (Kikkoman Corporation) so that the added concentration of ergothioneine became 10 ppm, 20 ppm, 50 ppm (EGR10, 20, 50). Regarding the soy sauce added with ERG at each concentration (the concentration was not disclosed to the panel), a drinking test was conducted by three professional panels using soy sauce without added ergothioneine (ERG0) as a control, and the sweetness was sensory evaluated by a two - point discrimination test. The results are shown in Table 21.

[0079] [Table 21] Soy sauce with 10 ppm or more of ERG added was evaluated by all panelists as having enhanced sweetness.

[0080] (2) Sweet soy sauce ERG was added to commercially available sweet soy sauces (Golden Purple, Fun Dokin Soy Sauce), and the same test as in (1) above was conducted. The results are shown in Table 22. [Table 22] Soy sauce with 10 ppm or more of ERG added was evaluated by all panelists as having enhanced sweetness.

[0081] [Test 13: Sweetness enhancement effect of prepared soy milk] ERG was added to commercially available prepared soy milk (Kikkoman Corporation) so that the final concentration of ergothioneine was 0.5 ppm, 1 ppm, 3 ppm, 5 ppm, 10 ppm, and 20 ppm to prepare sample prepared soy milk (EGR0.5 - 20). For prepared soy milk with ERG added at each concentration (the concentration was not disclosed to the panel), using prepared milk without ergothioneine added (ERG0) as a control, a drinking test was conducted by 3 professional panelists, and the sweetness was sensory evaluated by a two - point discrimination test. The results are shown in Table 23.

[0082] [Table 23] Prepared soy milk containing 3 ppm of ERG was evaluated by 2 panelists as having enhanced sweetness, and prepared soy milk containing 5 ppm of ERG was evaluated by all panelists as having enhanced sweetness. Also, prepared soy milk containing 40 ppm of ERG had an increased creamy feeling.

[0083] [Test 14: Sweetness enhancement effect of milk] ERG was added to commercially available milk so that the final concentration of ergothioneine was 0.5 ppm, 1 ppm, 3 ppm, 5 ppm, 10 ppm, and 20 ppm to prepare sample milk (EGR0.5 - 20). For milk added with ERG at various concentrations (the concentrations were not disclosed to the panel), a drinking test was conducted by three professional panels with milk without ergothioneine (ERG0) as a control, and the sweetness was sensory evaluated by a two-point discrimination test. The results are shown in Table 24.

[0084]

Table 24

Claims

1. A sweetening enhancer containing ergothioneine as an active ingredient.

2. A sweetening enhancer for food and drink containing a saccharide-based sweetening component, with ergothioneine as an active ingredient.

3. The sweetening enhancer according to claim 2, wherein the saccharide-based sweetening component is one or more selected from the group consisting of sucrose (table sugar), glucose (grape sugar), fructose (fruit sugar), fructose-glucose liquid sugar, oligosaccharide, starch syrup, trehalose, maltose (malt sugar), sugar alcohols such as sorbitol, mannitol, and xylitol.

4. A food and drink containing a saccharide-based sweetening component, characterized in that it contains ergothioneine, which is a sweetening enhancer, in an amount of 0.0001% by weight or more based on the sucrose content, 0.0001% by weight or more based on the glucose content, or 0.0003% by weight or more based on the fructose content, and has enhanced sweetness.

5. The food and drink according to claim 4, wherein the food and drink is a food, beverage, or seasoning.

6. The food and drink according to claim 4, wherein the food and drink is soy sauce, mirin, sweet sake, liquid sugar, prepared soy milk, or milk.

7. The food and drink according to claim 4, produced using an ergothioneine-high-producing koji strain.

8. A sweetening enhancer for food and drink containing a non-saccharide-based sweetening component, with ergothioneine as an active ingredient.

9. The sweetening enhancer according to claim 8, wherein the non-saccharide-based sweetening component is one or more selected from the group consisting of high-intensity sweeteners such as aspartame, acesulfame potassium, sucralose, stevia, lakanka, stevia, licorice, and sweet-tasting amino acids.

10. A food and drink containing a non-saccharide-based sweetening component, characterized in that it contains ergothioneine, which is a sweetening enhancer, in an amount of 0.0005% by weight or more based on the high-intensity sweetener content, or 0.0004% by weight or more based on the sweet-tasting amino acid content, and has enhanced sweetness.

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