Method for producing koji-containing food product, and koji-containing food product

Abstract

Provided is a method for producing a koji-containing food product, the method comprising a step for fermenting a mixture containing rice, Aspergillus oryzae, and water, and a step for heating the solid contained in the mixture. Also provided is a dried koji-containing food product, the food product including a decomposition product of rice fermentation by Aspergillus oryzae and inactivated Aspergillus oryzae.

Description

Method for producing food using koji and food using koji

[0001] The present invention relates to a method for producing a food product using koji and a food product using koji.

[0002] Patent Document 1 describes a liquid seasoning that has a good balance of umami, sweetness, and saltiness while maintaining the functions of salt koji, and is obtained by fermenting and maturing a mixture of rice koji, salt, and water at a low temperature, followed by solid-liquid separation.

[0003] JP 2014-50352 A

[0004] The liquid seasoning described in Patent Document 1 is obtained by fermenting and aging a mixture of rice koji, salt, and water, followed by solid-liquid separation to obtain the liquid used as the seasoning. The solid components from the solid-liquid separation are discarded as by-products, and there has been a demand for more effective use of resources. The present invention aims to provide a method for producing a koji-based food from the solid components and other by-products of the liquid seasoning, and to provide a koji-based food.

[0005] Thus, a first aspect of the present invention is a method for producing a koji-based food, comprising the steps of fermenting a mixture containing rice, koji mold, and water, and heating a solid contained in the mixture. A second aspect is the method for producing a koji-based food of the first aspect, in which the solid is heated at 80°C or higher and 140°C or lower. A third aspect is the method for producing a koji-based food of the first or second aspect, in which the solid is heated for 30 minutes to 5 hours or lower. A fourth aspect is the method for producing a koji-based food of any one of the first to third aspects, in which the mixture in the fermenting step contains salt and is fermented. A fifth aspect is the method for producing a koji-based food of the fourth aspect, in which the mixture is fermented at 4°C or higher and 40°C or lower. A sixth aspect is the method for producing a koji-based food of the fourth or fifth aspect, in which the mixture contains rice koji obtained by propagating koji mold on steamed rice, and water. A seventh aspect is the method for producing a koji-based food of any one of the first to sixth aspects, in which the mixture is further fermented with ethanol. An eighth aspect is a method for producing a koji-using food, comprising a step of heating rice koji produced by propagating koji mold on steamed rice. A ninth aspect is a method for producing a koji-using food of the eighth aspect, in which the rice koji is heated at 80°C or higher and 140°C or lower. A tenth aspect is a method for producing a koji-using food of the eighth or ninth aspect, in which the rice koji is heated for 30 minutes or longer and 5 hours or shorter. An eleventh aspect is a method for producing a koji-using food of any one of the eighth to tenth aspects, in which the rice koji is preheated at 50°C or higher and 75°C or lower before the step of heating the rice koji. A twelfth aspect is a method for producing a koji-using food of the eleventh aspect, in which the preheating of the rice koji is carried out for 3 hours or longer before the step of heating the rice koji. A thirteenth aspect is a dried koji-using food comprising a fermentation decomposition product of rice koji mold and inactivated koji mold. A fourteenth aspect is a koji-using food of the thirteenth aspect, in which the koji-using food further comprises salt. A fifteenth aspect is the koji-using food of the thirteenth or fourteenth aspect, wherein the koji-using food contains 3-furaldehyde. A sixteenth aspect is the koji-using food of any one of the thirteenth to fifteenth aspects, wherein peak A corresponding to a Maillard reaction product of cysteine ​​and glucose is detected in HPLC analysis and LC-MS analysis.A seventeenth aspect is the koji-using food of the sixteenth aspect, wherein (1) in a chromatograph under the following HPLC analysis conditions, when the retention time of Peak A is taken as 1.0, Peak B has a relative retention time of 1.1 to 1.6, (2) the absorption maximum wavelength of Peak B is 279 to 289 nm, and (3) in mass analysis of Peak B in positive ion mode by ESI-MS, Peak B has a peak with an m / z of 125.9 to 127.9. "HPLC analysis conditions" Extract: Extract with water in an amount four times the weight of the analyte. Mobile phase A: 0.1% by mass trifluoroacetic acid aqueous solution Mobile phase B: acetonitrile Isocratic conditions: mobile phase A 95%, mobile phase B 5% Flow rate: 0.6 mL / min Column: CAPCELL PAK C18 AQ (Osaka Soda Co., Ltd., 4.6 mm x 100 mm, 3 μm) Detection wavelength: 297 nm.

[0006] According to the first aspect of the present invention, it is possible to provide foods such as seasonings that have an excellent taste, such as richness, while maintaining the umami of koji from by-products of liquid shio-koji. According to the second and third aspects, it is possible to impart a good flavor, such as deep richness. According to the fourth and fifth aspects, it is possible to improve the flavor, such as the richness, of foods. According to the sixth aspect, it is possible to provide foods that have the umami of rice koji. According to the seventh aspect, it is possible to provide foods that have an alcoholic flavor and have improved shelf life due to spoilage prevention, sterilization, etc. According to the eighth aspect, it is possible to provide foods such as seasonings that have an excellent taste, such as richness, while maintaining the umami of koji, using rice koji. According to the ninth and tenth aspects, it is possible to impart a good flavor, such as deep richness. According to the eleventh and twelfth aspects, it is possible to mature rice koji (activate enzymes) and enhance the richness of products using koji. According to the thirteenth aspect, it is possible to provide foods that have an excellent flavor, such as richness, while maintaining the umami of rice koji. According to the fourteenth aspect, it is possible to provide foods that are even more excellent in flavor, richness, etc. According to the fifteenth aspect, the Maillard reaction proceeds, and it is possible to provide a food product having excellent flavor, richness, etc. According to the seventeenth and eighteenth aspects, it is possible to provide a food product having excellent flavor, richness, etc., due to the presence of a peak.

[0007] 1 is a process diagram showing an example of a conventional method for producing liquid shio-koji. 2 is a process diagram showing an example of a process for producing a koji-based food product of the first embodiment. 3 is a diagram showing absorption spectra of the food product of the present invention, a sample of the food product before heating, etc. 4 is a diagram showing FT-IR spectra of the food product of the present invention (a) and a sample of the food product before a heat-drying process (b). 5 is a graph showing the change in taste intensity over time (a) and the spread of taste in the mouth (b) in a sensory evaluation when the food product of the present invention is used in butter cookies. 6 is a process diagram showing an example of a process for producing a koji-based food product of the second and third embodiments. 7 is a graph showing the results of gas chromatography-mass spectrometry of the koji-based food product of the present invention, etc. 8 is a diagram showing an HPLC chromatograph of the koji-based food product of the present invention. 9 is a diagram showing the results of HPLC analysis, where (a) is an analysis graph of the koji-based food product and (b) is a graph of a Maillard reaction product of cysteine ​​and glucose. 10 is a diagram showing the UV spectrum of a sample. 11 is a diagram showing mass spectrometry graphs in ESI-MS positive ion mode, where (a) is a graph of the koji-based food product of the present invention and (b) is a graph of a Maillard reaction product of cysteine ​​and glucose. FIG. 1 is a graph showing a mass analysis graph in positive ion mode by ESI-MS for the koji-using food product of the first embodiment.

[0008] The following describes embodiments of the present invention. These descriptions and examples are intended to illustrate embodiments and do not limit the scope of the invention. In this disclosure, expressions such as "greater than or equal to xx and less than or equal to xx" or "xx to xx" that represent numerical ranges refer to numerical ranges that include the stated upper and lower limits, unless otherwise specified. The method for producing koji-based foods according to the first embodiment is characterized by including a step of fermenting a mixture containing rice, koji mold, and water, and a step of heating a solid contained in the mixture.

[0009] First, we will describe the koji-based food produced by the first embodiment. The koji-based food produced by this embodiment can provide foods obtained using this food with a rich, full-bodied flavor. The following mechanism is presumed to explain this. As described below, by adding koji to rice and fermenting it, the sugars, proteins, and other components in the rice are decomposed by various decomposing enzymes, producing reducing sugars, amino acids, peptides, and other components. Conventionally, foods obtained by fermentation have not been further heated. However, in this embodiment, heating solids containing these decomposition products, particularly solids after solid-liquid separation, initiates the Maillard reaction, producing melanoidins, which impart a rich flavor and a lasting flavor. It is also known that koji fermentation produces aroma components such as amines and aldehydes, which impart a rich aroma to foods. Furthermore, by using rice, dietary fiber derived from rice and sugars produced by rice decomposition impart a rich texture. It is believed that the richness of these flavors, aromas, and textures exert different effects depending on the food ingredients used, resulting in richness, umami, and other flavors.

[0010] A method for producing koji-based foods according to the first embodiment will be described in detail below. First, a mixture containing rice, koji mold, and water is fermented. There is no limit to the type of food that can be obtained as long as it is obtained by fermenting rice, koji mold, and water. In this embodiment, salt is typically added to produce shio-koji, but it is also possible to produce amazake without adding salt, to produce sake by adding yeast, or to produce mirin by adding alcohol.

[0011] The following describes the production of shio-koji. Typically, koji mold is added to rice to produce what is called rice koji. The rice koji used in this embodiment can be prepared according to a conventional method for producing rice koji. Specifically, it is obtained by spraying koji mold (also called seed koji) on steamed rice obtained by steaming rice and allowing it to grow under conditions optimal for the koji mold. The koji mold may be grown using an automatic fermenter (e.g., HK-60, manufactured by Yaegaki Food & System Co., Ltd.) by culturing it at 25 to 40°C for 2 to 4 days. Commercially available rice koji may be used in the present invention. Rice may be of the non-glutinous variety, such as glutinous rice, or sake rice, preferably polished rice (white rice). Either Japonica or Indica rice may be used as non-glutinous rice. Rice may be washed, soaked in water, and drained as needed.

[0012] The koji mold is not particularly limited as long as it is a koji mold used in conventional koji production. Suitable examples include Aspergillus species such as Aspergillus oryzae and Aspergillus sojae. Commercially available koji molds sold as seed koji may be used, or cultured koji molds may be used. The koji mold may be in the form of granules or powder. The koji mold used in this embodiment is preferably a koji mold with high saccharification power and protease production ability, specifically koji mold for miso, koji mold for rice koji, or koji mold for soy sauce, more preferably koji mold for rice koji or koji mold for miso, and even more preferably koji mold for miso. These may be used alone or in combination of two or more.

[0013] The mixture containing rice, koji mold, and water for fermentation is usually in the form of rice in water. When producing shio-koji by fermentation, salt and water are mixed with the rice koji obtained above. These may be added simultaneously or sequentially. The rice koji is mixed in a proportion of 30% to 70% by mass, preferably 35% to 60% by mass, more preferably 40% to 55% by mass, and even more preferably 45% to 50% by mass. The salt is mixed in a proportion of 2% to 20% by mass, preferably 3% to 18% by mass, more preferably 4% to 16% by mass, and even more preferably 5% to 15% by mass. The salt can suppress microbial growth in the mixture. If the amount of salt is too small, microbial growth tends to occur.

[0014] A mixture containing rice, koji mold, and water is fermented. The mixture is preferably fermented and aged at a temperature that does not inactivate the koji mold-derived enzymes contained in the mixture. Here, koji mold-derived enzymes refer to enzymes produced by koji mold, including, for example, amylase, protease, lipase, and cellulase. These enzymes are heat-sensitive, and proteases in particular are inactivated by fermentation at temperatures above 60°C. In a preferred embodiment, the fermentation temperature is 4 to 40°C, preferably 20 to 38°C, more preferably 25 to 35°C, and even more preferably 28 to 32°C. At these temperatures, the koji mold-derived enzymes are not inactivated. During fermentation, not only does koji mold ferment, but koji mold-derived enzymes also typically decompose starch, proteins, lipids, and other components contained in rice, a process sometimes referred to as saccharification. The fermented mixture (fermented and aged product) is generally called "shiokoji" (salt koji) and is sometimes sold commercially in this form.

[0015] In a preferred embodiment, fermentation is carried out until the Brix of the fermented mixture (fermented and matured product) increases by 4% or more, preferably 6% or more, and more preferably 9% or more, based on the Brix value on the first day of fermentation. Here, Brix refers to the value measured using a refractometer, and the value varies depending on the increase or decrease of sucrose, salt, various amino acids, glucose, maltose, and other components. Therefore, the Brix value varies depending on the composition of the raw materials used in the brewing liquid. For example, in the case of a brewing liquid containing 50% by mass of rice koji, 13% by mass of salt, and 37% by mass of water, fermentation is carried out until the Brix of the fermented mixture reaches 37% or more, preferably 39% or more, and more preferably 41% or more. Brix can be measured using methods known to those skilled in the art, such as a commercially available handheld refractometer or digital refractometer. Generally, measuring Brix is ​​easier than measuring direct sugar concentration.

[0016] In a preferred embodiment, fermentation is carried out until the direct sugar concentration of the fermented mixture increases by 8% or more, preferably 12% or more, and more preferably 18% or more, based on the direct sugar concentration measured on the first day of fermentation. Here, direct sugar refers to direct reducing sugar, and the direct sugar concentration varies depending on the composition of the raw materials used in the brewing liquid. For example, in the case of a mixture containing 50% by mass of rice koji, 13% by mass of salt, and 37% by mass of water, fermentation is carried out until the direct sugar concentration of the fermented brewing liquid reaches 16% or more, preferably 20% or more, and more preferably 26% or more. The direct sugar concentration can be measured using methods known to those skilled in the art, such as the modified Somogyi method ( Journal of the Agricultural Chemical Society of Japan 28(3) 171-174 (1954)) or the method specified in the Japanese Agricultural Standards for Soy Sauce.

[0017] In a more preferred embodiment, fermentation is carried out until the Brix of the fermented mixture (fermented and matured product) increases by 4% or more and the direct sugar concentration increases by 8% or more, preferably until the Brix increases by 6% or more and the direct sugar concentration increases by 12% or more, and more preferably until the Brix increases by 9% or more and the direct sugar concentration increases by 18% or more, based on the values ​​on the first day of fermentation.When the Brix of the fermented mixture (fermented and matured product) increases by 4% or more and the direct sugar concentration increases by 8% or more, based on the values ​​on the first day of fermentation, the balance of umami, sweetness, and saltiness is better. According to one embodiment of the present invention, for example, in the case of a brewing liquid containing 50% by weight of rice koji, 13% by weight of salt, and 37% by weight of water, fermentation is preferably carried out until the fermented mixture (fermented and matured product) has a Brix of 37% or more and a direct sugar concentration of 16% or more, more preferably until the Brix is ​​39% or more and the direct sugar concentration is 20% or more, and even more preferably until the Brix is ​​41% or more and the direct sugar concentration is 26% or more.

[0018] In a preferred embodiment, fermentation is carried out at low temperature for 1 to 60 days, preferably 2 to 30 days, more preferably 3 to 21 days, even more preferably 4 to 14 days, even more preferably 6 to 13 days, particularly preferably 8 to 12 days, and most preferably 10 days. The lower the temperature, the longer the fermentation period, due to the decreased activity of the koji-derived enzymes. Therefore, in a more preferred embodiment, fermentation is carried out at 20 to 38°C for 3 to 21 days, more preferably 4 to 14 days, even more preferably 6 to 13 days, particularly preferably 8 to 12 days, and most preferably 10 days. In a further preferred embodiment of the present invention, fermentation is carried out at 20 to 38°C for 3 to 21 days, until the Brix of the fermented mixture (fermented and matured product) increases by 4% or more and the direct sugar concentration increases by 8% or more, based on the values ​​on the first day of fermentation.

[0019] In a post-fermentation step, the solids in the mixture are heated. In a preferred embodiment, the solids and liquid are separated by a solid-liquid separation method, and the resulting solids are heated. The solid-liquid separation method is not particularly limited, and may be a method typically used for mirin or soy sauce. Examples include compression filtration using a compression filter, compression using a filter cloth, and solid-liquid separation using a centrifuge, with compression filtration being preferred. The filtrate obtained by solid-liquid separation can be used directly as a liquid seasoning (liquid shio-koji) using conventional technology.

[0020] The solid component obtained by solid-liquid separation is obtained as pressed cake, which, as mentioned above, has traditionally been discarded as a by-product. In this embodiment, the pressed cake is crushed to approximately 5 mm using a mincer or the like to form a powder, and then heated. During this heating process, the powder dries and the resulting food is given a rich, umami-like flavor. To achieve this, the heating temperature is preferably 80°C or higher and 140°C or lower, more preferably 100°C or higher and 120°C or lower. Furthermore, the heating temperature is preferably 30 minutes to 5 hours, more preferably 30 minutes to 3 hours, and even more preferably 1 hour or higher. In particular, temperatures around 80°C or lower tend to result in insufficient heating, while temperatures around 140°C or higher tend to result in the powder becoming "burnt," making it unsuitable for food. Furthermore, koji mold is further killed by the addition of ethanol (alcohol) during the fermentation process, as described below. It is usually completely killed by heating the pressed cake and inactivated after drying. When using koji mold in dishes that involve a pickling process, it is preferable that all of the koji mold be dead, since surviving koji mold will decompose ingredients such as meat and fish. However, if cooking is to be performed immediately after addition or if ingredients that are not susceptible to enzymatic decomposition are used, it is acceptable for some of the koji mold to remain viable. If it is necessary to confirm the inactivation of koji mold, this can be confirmed, for example, by culturing it on potato dextrose agar medium. Furthermore, when multiple dyes are used in the fluorescent staining method, an image staining bacteria with respiratory activity and an image staining all bacteria are obtained, respectively. By overlaying the two resulting images with different colors, it is possible to confirm the presence and proportion of bacteria without respiratory activity (dead bacteria). Furthermore, whether the bacteria appearing in the image are the control koji mold can be confirmed, for example, by examining the DNA sequence of the bacteria. After heating, the color of the powder preferably darkens compared to before drying, changing to a light brown or the like. As mentioned above, this is thought to be because the sugars and proteins in rice are broken down by various enzymes during fermentation, resulting in reducing sugars, amino acids, peptides, etc., which undergo the Maillard reaction when heated, producing melanoidin, a reaction product.Because melanoidin is not a single substance, it is difficult to grasp its formation. However, in addition to the change in color tone, the absorption peak in the absorption spectrum of Example 3 (FIG. 3A) shifts to a longer wavelength than before heating, at about 325 nm, similar to Reference Example C in which lysine and galactose were mixed and heated, and the FT-IR spectrum of Example 4 (FIG. 4A) shows a change in the fingerprint region (1500 cm). －１ From 650 cm －１ ) is evidenced by an increased number of peaks.

[0021] The resulting powder is classified into powders of a preferred size, typically using a sieve or other means commonly used in the food industry, to obtain the koji-based food of this embodiment. The smaller the powder, the better the texture. As explained above, this food is in a dry state and contains a fermentation hydrolyzate of rice by koji mold, salt, and inactivated koji mold. Given its composition, this food may be eaten as is, but is particularly preferred for use as a seasoning for other dishes and sweets. The dishes to which it can be added are not particularly limited, but examples include the following: Side dishes: hamburger steak, curry, cod roe, rolled omelet, cream stew, etc. Sauces and soups: consommé soup, meat sauce, white sauce, cheese sauce, miso ramen soup, miso soup, anchovy sauce, etc. Sweets: lacto ice cream, cookies, milk chocolate, white chocolate, potato chips, scones, etc. The amount added to dishes, etc., depends on the dish used, but is preferably between 0.1% and 5% by mass. The type of flavor obtained varies depending on the dish used, the amount used, the environment in which it is used, etc., but can include a milky, cheesy, broth-like, spicy, sour, etc. Other effects on the taste of dishes may include suppressing saltiness, masking the smell of livestock, and prolonging the spiciness of chili peppers, etc.

[0022] It is also preferable to further add ethanol (alcohol) to the food of this embodiment from the viewpoints of improving flavor and shelf life through sterilization. The addition may be made at any stage, such as during the rice fermentation process or the press cake heating process. In some cases, yeast may be added to the mixture before fermentation to produce it. The amount of ethanol is preferably 0.5% by mass or more and 10% by mass or less, more preferably 1% by mass or more and 6% by mass or less, and even more preferably 2% by mass or more and 5% by mass or less, relative to the koji-based food of this embodiment. If the concentration is too low, the effect of the addition tends not to be apparent, while if the concentration is too high, the alcohol odor and taste tend to be prominent, which is undesirable.

[0023] Next, methods for producing koji-based foods according to the second and third embodiments will be described with reference to FIG. 6 . The method for producing a koji-based food according to the second embodiment includes a step of heating rice koji, which is obtained by cultivating koji mold on steamed rice. Furthermore, the method for producing a koji-based food according to the third embodiment, as in the method for producing a koji-based food according to the second embodiment, is characterized by preheating the rice koji at a temperature of 50°C to 75°C before heating it. In FIG. 6 , the "preheating" step shown in the figure is not performed in the second embodiment, while in the third embodiment, the "preheating" step is performed before the "heat-drying" step. The koji-based foods produced according to the second and third embodiments (hereinafter abbreviated as "koji-based food according to the second embodiment" and "koji-based food according to the third embodiment," respectively) differ from the koji-based food produced according to the first embodiment in their production methods, and in particular, do not require a step of fermenting a mixture containing rice, koji mold, and water. However, like the koji-based food according to the first embodiment, the koji-based foods according to the second and third embodiments can provide foods prepared using them with a rich, full-bodied flavor. The mechanism behind this is presumed to be as follows: Rice contains sugars, proteins, and other compounds. When koji mold is grown on steamed rice to obtain rice koji, and when the resulting rice koji is heated, these compounds are decomposed by various decomposing enzymes to produce reducing sugars, amino acids, peptides, and other compounds. As mentioned above, foods obtained by fermentation have not traditionally been further heated. However, in the second and third embodiments, these decomposition products are contained in the rice koji, and heating the rice koji induces a Maillard reaction, producing melanoidins, which impart richness to the flavor and also contribute to the long-lasting flavor. Furthermore, in the third embodiment, preheating the rice koji before heating allows the rice koji to mature and activates the enzymes contained therein, thereby enhancing the richness of the koji-based food. Furthermore, in the second and third embodiments, the use of rice contributes to richness in texture through the rice-derived dietary fiber and sugars produced by rice decomposition. It is believed that the richness of these flavors and textures exerts different effects depending on the food ingredients used in combination, resulting in richness, umami, and other flavors.

[0024] Next, a method for producing a koji-using food according to the second embodiment will be described in detail. Rice koji, which is obtained by propagating koji mold on steamed rice, is heated. Rice koji can be produced according to a conventional method for producing rice koji. Specifically, koji mold (also called seed koji) is sprinkled on the steamed rice obtained by steaming rice, and the koji mold is allowed to propagate under optimal conditions. Propagation of the koji mold may be carried out by culturing it at 25 to 40°C for 2 to 4 days using an automatic fermenter (e.g., HK-60, manufactured by Yaegaki Food & System Co., Ltd.). Commercially available rice koji may be used. The rice, koji mold, and other ingredients used as the raw materials for the rice koji can be the same as those described for the koji-using food according to the first embodiment.

[0025] Next, the rice koji is heated. During this heating process, in order to dry the entire rice koji and impart richness, umami, flavor, and the like to the resulting food, the heating temperature is preferably 80°C or higher and 140°C or lower, more preferably 100°C or higher and 120°C or lower. The heating temperature is preferably 30 minutes to 5 hours, more preferably 30 minutes to 3 hours, and even more preferably 1 hour or higher. In particular, temperatures around 80°C or lower tend to result in insufficient heating, while temperatures around 140°C or higher tend to result in the rice koji becoming "burnt," making it undesirable for food. The koji mold dies during this heating process and is usually completely inactivated after drying. When using the koji mold in dishes that require a pickling process, it is preferable that all of the koji mold be dead, since surviving koji mold decomposes ingredients such as meat and fish. However, if cooking is to be done immediately after addition or if ingredients that are not susceptible to enzymatic decomposition are used, it is acceptable for some of the koji mold to remain viable. The inactivation of koji mold, the presence and proportion of dead bacteria, and whether the bacteria are koji mold can be confirmed using the same methods as in the first embodiment described above. After heating, as with the powder in the first embodiment, the color of the rice koji preferably darkens compared to before drying, turning light brown or similar. This is thought to be because, as described above, sugars, proteins, etc. in rice are decomposed by various decomposing enzymes when turning into rice koji, producing reducing sugars, amino acids, peptides, etc., which further decompose during heating, and the Maillard reaction that occurs during heating produces melanoidin, a reaction product. Because melanoidin is not a single substance, it is difficult to determine its formation; however, evidence of its formation includes not only the color change but also the production of some Maillard reaction products, as shown in Example 13.

[0026] The resulting powder is then classified using a method commonly used in the food industry, such as a sieve, to obtain a powder of a desired size, resulting in the koji-based food product of the second embodiment. The smaller the powder, the better the texture. As explained above, this food product is in a dry state, containing the fermentation decomposition product of rice by koji mold and inactivated koji mold.

[0027] Next, a method for producing a koji-based food product according to a third embodiment will be described. In the third embodiment, the "preheating" step, circled by a dotted line in FIG. 6 , is performed before the "heat drying" step. Specifically, the rice koji, which is made by propagating koji mold on steamed rice, is preheated before being heated. The preheating temperature is preferably 50°C or higher and 75°C or lower, more preferably 55°C or higher and 70°C or lower. The preheating time is preferably 3 hours or longer, even more preferably 4 hours or longer. While there is no theoretical upper limit to the preheating time, a prolonged period of time is ineffective, so practically, a period of one day or less is preferable. By selecting these temperatures and times, the enzymes derived from koji mold in the rice koji can be matured and activated at a temperature that does not inactivate (deactivate). As a result of the maturation and activation, the koji-based food product can have a stronger full-bodied flavor compared to a product without preheating (the koji-based food product of the second embodiment). In the third embodiment, the rice koji used and the steps after preheating are the same as those in the method for producing a koji-based food according to the second embodiment described above. After preheating the rice koji, it is heated and dried, crushed, and classified in the same manner as in the second embodiment to obtain a powdered product, the koji-using food product of the third embodiment (see Figure 6). The obtained koji-using food product of the third embodiment is in a dry state, containing fermentation decomposition products of rice by koji mold and inactivated koji mold, just like the koji-using food product of the second embodiment.

[0028] While both the koji-based foods of the second and third embodiments may be eaten as is due to their composition, they are particularly preferred for use as seasonings for other dishes and confectioneries. The type of dish to which they are added is not particularly limited, and examples of foods similar to those described for the koji-based foods of the first embodiment include those described for the koji-based foods of the first embodiment. The amount added to a dish, etc., depends on the dish, etc., but is preferably 0.1% by mass or more and 5% by mass or less. The type of flavor obtained varies depending on the dish used, the amount used, the environment used, etc., but includes milky, cheesy, brothy, spicy, sour, etc. Other effects on the taste of dishes, etc., include suppressing saltiness, masking the odor of livestock, and prolonging the spiciness of chili peppers, etc. The koji-based foods of the second and third embodiments may also preferably be further supplemented with ethanol (alcohol) from the perspectives of improving flavor and shelf life through sterilization. Salt can also be added. The amounts and effects of ethanol and salt are the same as those of the koji-based foods of the first embodiment.

[0029] The koji-using foods of the first to third embodiments are all dried foods containing a fermentation hydrolyzate of rice by koji mold and inactivated koji mold. By including Maillard reaction products, these foods can enhance the richness, umami, and other properties of other foods. As an example, each koji-using food preferably contains 3-furaldehyde, one of the intermediate products of the Maillard reaction, as described in Example 12, although this is not limited thereto. From the perspective of enhancing the richness, umami, and other properties of other foods, the content of 3-furaldehyde in the koji-using food is preferably 7 ng / g or more, and particularly preferably 10 ng / g or more. Furthermore, each koji-using food preferably detects peak A, corresponding to the Maillard reaction product of cysteine ​​and glucose, in HPLC and LC-MS analysis, as described in Example 13, although this is not limited thereto. The compound of Peak A has a maximum absorption wavelength in the UV spectrum within the range of 297 nm±5 nm, particularly within the range of 297±3 nm, and in mass analysis by ESI-MS in positive ion mode, it has a peak with an m / z of 125.9 or more and 127.9 or less. Furthermore, although not limited thereto, each koji-using food preferably has: (1) in a chromatograph under the HPLC analysis conditions described in Example 13, when the retention time of Peak A is taken as 1.0, Peak B has a relative retention time of 1.1 or more and 1.6 or less; (2) the maximum absorption wavelength of Peak B is 279 nm or more and 289 nm or less; and (3) in mass analysis by ESI-MS in positive ion mode, Peak B has a peak with an m / z of 125.9 or more and 127.9 or less.

[0030] The following examples illustrate embodiments of the present invention in detail, but the present invention is not limited to these examples. In the following description, unless otherwise specified, the amounts used, such as "parts" and "%," are based on mass. [Example 1] Rice koji and liquid seasoning were prepared according to the process shown in Figure 1, and a koji-using food product of the first embodiment was prepared according to the process shown in Figure 2. (1) Preparation of Rice Koji: Rice was soaked in 1.2 times the amount of water for 12 hours, drained for 2 hours, and then steamed for 45 minutes using a steamer (manufactured by Hanyuda Iron Works Co., Ltd.) to obtain steamed rice. The steamed rice was cooled to 30°C, and seed koji (miso seed koji, obtained from Higuchi Matsunosuke Shoten Co., Ltd.) was sprinkled and mixed in several batches so that 0.3 g of seed koji was used per 1 kg of steamed rice (steamed rice:seed koji = 1000:0.3) (seed cutting). The rice mixed with the koji starter was cultured at 35°C for 42 hours in an automatic fermenter (HK-60, manufactured by Yaegaki Food & System Co., Ltd.) with occasional stirring to obtain rice koji. (2) Preparation of liquid seasoning 50 kg of the obtained rice koji, 13 kg of salt (normal salt), and 37 L of water were mixed to obtain a mash. The mash was fermented and aged at 30°C for 10 days to obtain a matured product. The matured product was press-filtered using a press filter (equipment name: laboratory press, manufactured by NSK Engineering Co., Ltd.), and the filtrate was obtained as a liquid seasoning, while press cake was obtained as a solid component. (3) Preparation of koji-based food The press cake obtained was roughly crushed using a chopper (manufactured by Zenmigo Co., Ltd., model: 10B) and then heated and dried at 105°C for 2 hours using a three-stage band dryer. The obtained lees were pulverized in a hammer mill and passed through a 40 mesh sieve using a vibrating sieve (Tokuju Manufacturing Co., Ltd., model: TMC-70-2S) to obtain a powder that passed through a 40 mesh sieve as the target koji-based food. 65 kg of the koji-based food of the first embodiment was obtained from 100 kg of pressed lees. The koji-based food obtained in (3) was used in the following Examples up to Example 8.

[0031] Example 2 The free amino acid composition and sugar composition of the resulting koji-based food were measured using the following method. Amino acid analysis: Approximately 1 g or 2 g of the koji-based food was accurately weighed and extracted with 50 mL of 75% ethanol under reflux at 80°C for 30 minutes. Impurities were then removed by filtration, and the resulting solution was brought to a constant volume of 100 mL. A 4 mL aliquot of this extract was then concentrated to dryness using an evaporator (Tokyo Rikakikai Co., Ltd., Rotary Evaporator K-1000). The solution was then completely dissolved in 8 mL of citrate buffer (pH 2.2). The filtrate was then filtered through a 0.45 μm membrane filter (Toyo Roshi Kaisha, Ltd., trade name "DISMIC 26CS045AN"), and the amino acids were analyzed using a Shimadzu LC-VP amino acid analysis system (Shimadzu Corporation) by high-performance liquid chromatography with OPA (o-phthalaldehyde) post-column derivatization and fluorescence detection. Reducing Sugar Analysis 490 mL of water was added to 10 g of the koji-based food product and mixed by stirring. 5 mL of the mixed solution was placed in a beaker, and 95 mL of water was added and mixed again by stirring. The resulting solution was filtered through a 0.45 μm membrane filter (manufactured by Toyo Roshi Kaisha, Ltd., trade name "DISMIC 26CS045AN"), and the reducing sugar content was analyzed using a Shimadzu high-performance liquid chromatograph reducing sugar analysis system (manufactured by Shimadzu Corporation). The measurement results are shown in Tables 1 and 2, respectively, along with the results for the state before the heat-drying step (3) above and the results for a commercially available liquid shio koji. The nutritional information (theoretical values ​​per 100 g) of the resulting koji-based food product as a food product is also shown in Table 3.

[0032]

[0033]

[0034] In Table 1, "-" indicates a value below the detection limit. Table 1 shows that the free amino acids have decreased compared to before the drying process, but no significant specificity for each amino acid is observed. Table 2 shows that all amino acids except fructose have decreased compared to before the drying process. Furthermore, Tables 1 and 2 suggest that heating causes amino acids and reducing sugars to produce melanoidins through the Maillard reaction.

[0035] Example 3: The absorption spectra of the resulting koji-based food and the sample before the heat-drying process were analyzed. Specifically, 10 volumes of distilled water were added to each sample, and the samples were pulverized and micronized using a homogenizer (Nippon Seiki Seisakusho, US-150T). The resulting solution was centrifuged at 3,000 rpm for 20 minutes using a centrifuge (Kokusan Co., Ltd., refrigerated / tabletop centrifuge H-30R). The resulting supernatant was filtered through a 0.45 μm membrane filter (Toyo Roshi Kaisha, product name "DISMIC 26CS045AN") and the absorbance at each wavelength was measured using a spectrophotometer (Shimadzu Corporation, UV-1280 UV-Visible Spectrophotometer). The results are shown in the absorption spectrum diagram in Figure 3. In the figure, A is the koji-based food sample (Example), and B is the sample before the heat-drying process. As a reference example, an aqueous solution containing equal amounts of lysine and galactose was heated at 105°C for 2 hours, and a sample was similarly pulverized, micronized, centrifuged, filtered, and measured. The results are shown in Figure 3 as Reference Example C. As shown in Figure 3, the absorption spectrum peak of sample B before heating was near 300 nm, but the peak of the koji-based food A of the example shifted to a longer wavelength near 325 nm after heating. Reference Example C, in which a mixture of lysine and galactose was heated, also showed a peak near 325 nm, similar to the example. In C, melanoidin was produced by the Maillard reaction of lysine and galactose, and in Example A, as inferred from Tables 1 and 2, melanoidin was also produced by the Maillard reaction of sugars, amino acids, peptides, etc. present in the pressed cake.

[0036] Example 4 The obtained koji-based food product and the sample before the heat-drying process were placed directly on the sample stage, and the FT-IR spectrum (measuring device: IRAffinity-IS, manufactured by Shimadzu Corporation) was analyzed. The results are shown in Figures 4(a) and 4(b). The fingerprint region (1500 cm), which tends to show a substance-specific spectrum, －１ From 650 cm －１ ) the number of peaks increased in the koji-based food of the present invention. This indicates that during the heat-drying process, sugars, amino acids, peptides, etc. present in the pressed cake undergo a Maillard reaction, producing a large number of substances including melanoidins.

[0037] [Example 5] <Sensory evaluation> A sensory evaluation was carried out by trained expert panelists (hereinafter referred to as "panelists") on each of the following foods, with and without the koji-based food (Example) added (Example). (5-1) Butter cookies Butter cookies (Control) were made from the ingredients of the following composition and baked at 170°C for 10 minutes, and butter cookies (Example) were made in the same manner except that 37.5 g of the koji-based food of the present invention was further added. A sensory evaluation was carried out by 10 panelists. -Butter Cookie Ingredients- Wheat flour: 250g Unsalted butter: 100g Brown sugar: 100g Whole egg: 1 The change in taste intensity was evaluated by absolute rating (strongest: 1, weakest: 0) at 0, 5, 10, 15, and 20 seconds after placing the object in the mouth, and the average value for each time period among 10 panelists was calculated. The results are shown as a graph of time change in Figure 5(a). At all times, Example 1 tasted stronger than Control 2. In addition, the absolute rating of the spread of taste in the mouth (strongest: 1.2, weakest: 0) was calculated, and the average value for each panelist was calculated and shown in Figure 5(b). The Example exhibited a greater spread of taste in the mouth.

[0038] (5-2) Potato Chips A seasoning (control) consisting of the following ingredients and a seasoning (example) prepared in the same manner except that 7.2 parts of dextrin and 45 parts of the koji-containing food product of the present invention were used instead of 52.2 parts of dextrin were used. -Seasoning-Ingredients- Anhydrous crystalline glucose: 40 parts Butter flavor: 1 part Soy sauce flavor: 1 part Roasted soy sauce flavor: 1 part Finely powdered silicon dioxide: 0.8 parts Potato starch: 4 parts Dextrin: 52.2 parts Commercially available lightly salted potato chips were purchased, and seasoning powder such as salt on the surface was removed as much as possible with a brush. The potato chips and seasoning (example or control) were mixed in a ratio of 92 parts:8 parts, and a sensory evaluation was conducted by 13 panelists. The sensory evaluation was carried out using a two-point discrimination method, in which participants held the samples in their mouths and then swallowed them to select the sample with a good, strong body. The results of the number of participants' selections are shown in Table 4.

[0039] (5-3) Salted cod roe Commercially available salted cod roe was purchased, the membrane of the cod roe was removed, and only the egg grains were used. The koji-based food product of the present invention was added to salted cod roe in an amount of 0.5% and mixed, and compared with salted cod roe without additives (control). Sensory evaluation was performed by 13 panelists using a two-point discrimination method, who put the sample in their mouths and then swallowed it, and selected the sample with the strongest umami and rich flavor. The results of the number of people who selected are shown in Table 4.

[0040] (5-4) Miso Ramen Soup A comparison was made between miso ramen soup (control) and miso ramen soup (Example) containing 0.25% of the koji-based food product of the present invention. Sensory evaluation was performed by 13 panelists using a two-point discrimination method, who held the samples in their mouths and then swallowed them to select the sample with the strongest umami and richness. The results of the number of people who selected are shown in Table 4.

[0041] (5-5) Chocolate 150 parts of chocolate (black chocolate or white chocolate) was melted in a hot water bath, mixed with 100 parts of feuillantine chocolate and 1.5 parts of the koji-based food of the present invention, and then cooled in a refrigerator to produce a round feuillantine chocolate. On the other hand, feuillantine chocolate (control) was prepared in the same manner except that the koji-based food of the present invention was not mixed, and a sensory evaluation was performed. The sensory evaluation was performed using a two-point discrimination method by 13 panelists, who held the chocolate in their mouths and then swallowed it to select samples with a strong umami and rich flavor. The results of the number of people who selected each of the black chocolate and white chocolate are shown in Table 4.

[0042] (5-6) Dashimaki Eggs A mixture of the following ingredients was poured into a mold and baked in a steam convection oven at 160°C for 30 minutes to obtain a dashimaki egg (control). -Dashimaki Egg Ingredients- ・Chicken eggs: 10 ・Bonito stock: 150 mL ・Mirin: 27 mL ・Sake: 40 mL ・White stock: 27 mL Furthermore, a dashimaki egg (Example) was produced in the same manner, except that 7.5 g of the koji-based food product of the present invention was further added. A sensory evaluation was performed on the Example and Control dashimaki eggs. The sensory evaluation was performed using a two-point discrimination method by eight panelists, who put the samples in their mouths and then swallowed them to select the sample with the strongest umami and rich flavor. The results for the number of people selected are shown in Table 4.

[0043] (5-7) White Sauce A white sauce (control) was prepared by simmering the following ingredients. A white sauce (example) was also prepared in the same manner, except that 9 parts of the koji-based food product of the present invention was added to the following ingredients. -White Sauce Ingredients- Chicken breast: 300 parts Liquid Shio-Koji (Hanamaruki Co., Ltd.): 15 parts White sauce: 300 parts Milk: 150 parts Salt: 2.4 parts Onion: 200 parts Bunashimeji mushrooms: 100 parts Unsalted butter: 15 parts A sensory evaluation was conducted on the example and control white sauces. The sensory evaluation was conducted by eight panelists using a two-point discrimination method. They put the samples in their mouths, swallowed them, and selected the sample with the strongest umami and rich flavor. The results for the number of people selected are shown in Table 4.

[0044] (5-8) Scones Scones (control) were made using the following ingredients. Furthermore, scones (example) were made in the same manner, except that 12 g of the koji-based food of the present invention was further added to the following ingredients. To make the scones, weak flour, baking powder, sugar, and salt, along with the koji-based food if used, were mixed together, and then butter was added and kneaded to form a crumbly shape. Meanwhile, milk was added to beaten eggs and mixed, and this was lightly mixed with the weak flour and other ingredients previously mixed, molded, and baked in an oven at 180°C for 15 minutes to produce scones. - Scone Ingredients - ・Strong flour: 200 g ・Baking powder: 8 g ・Sugar: 30 g ・Butter: 70 g ・Egg: 1 ・Milk: 50 g ・Salt: 1 g A sensory evaluation was performed on the example and control scones. The sensory evaluation was carried out by eight panelists using a two-point discrimination method, who put the samples in their mouths, swallowed them, and selected the samples with the strongest umami and richness. The results of the number of people who selected are shown in Table 4.

[0045] In all the foods, the results showed that the foods using the koji of the present invention had a stronger body and flavor, with a significant difference.

[0046] <Sensory evaluation> The written responses for the examples of the present invention and the control in the sensory evaluation of each food are compared below. (5-2) Potato chips Example - The initial taste (saltiness) was mild. - The buttery taste (milk taste) was enhanced. - The umami taste lingers. Control - The salty taste comes first. - The buttery taste (milk taste) was not felt very much. (5-3) Salted cod roe Example - Strong taste from the middle taste to the aftertaste. - The salty taste was felt mild. Control - The salty taste was felt strongly. (5-4) Miso ramen soup Example - The initial taste (salty taste) was mild. - The aftertaste became stronger from the middle taste, and the umami taste lingered in the aftertaste. Control - The salty taste was felt first, and the subsequent flavor quickly disappeared. (5-5) Chocolate White chocolate Example - The milky taste was enhanced. - The middle taste was enhanced. Control - The milky taste was felt first, and then quickly disappeared. Dark Chocolate Example - Bitterness is masked. - Richness of fats and oils is enhanced. - Aftertaste is enhanced from the middle. Control - Bitterness comes first. - Richness is not felt very much. (5-6) Rolled Egg with Dashi Example - Aftertaste is long. - Dashi taste is felt strongly. Control - Dashi taste is felt at the same time as egg taste, but it disappears quickly. (5-7) White Sauce Example - Milk taste is felt stronger. - Butter taste is felt stronger. Control - Salt taste comes first. - Flavor is not felt very strong. (5-8) Scone Example - Butter taste is felt stronger. - Texture is crispy. Control - Flavor is not felt strong. - Texture is crumbly.

[0047] [Example 6] The koji-based foods obtained in Example 1 assumed a lighter brown to ochre color upon heating than the pressed cake, and as shown in Example 5, each food was imparted with richness, umami, and the like. Instead of heating at 105°C for 2 hours as in Example 1, heating was carried out at the following temperatures and times, and the resulting powders were evaluated based on the color tone of the powders obtained. - 70°C, 1 hour: Almost no change in color tone was observed before and after heating. - 80°C, 30 minutes: The color tone change was slightly less than in Example 1. - 100°C, 1 hour: A color tone change similar to that in Example 1 was observed. - 120°C, 1 hour: A slightly reddish color tone was observed compared to Example 1. - 140°C, 30 minutes: The color tone was more reddish than in Example 1, and a faint burnt odor was observed.

[0048] Example 7 Sensory Evaluation: Suppression of Saltiness To examine the suppression of saltiness (a salty taste that directly irritates the tongue) of the koji-based food of the present invention, panelists conducted the following sensory evaluation. (7-1) Saline solution A 1.0% (w / v, mass-to-volume ratio percentage) saline solution (control) and the koji-based food obtained in Example 1 were added to this saline solution to prepare saline solutions with a koji-based food concentration of 0.2% (w / v) (Example; 2 g of koji-based food per 1 L of saline solution) and then subjected to a sensory evaluation. For the sensory evaluation, 11 panelists held the control and Example saline solutions in their mouths and then swallowed them, and evaluated the saltiness using the following 5-point rating system, with the panelists' average being calculated. "Saltiness Evaluation" Weak 1 2 3 4 5 Strong The evaluation results are as follows: The koji-based food of the present invention demonstrated a statistically significant (p<0.01) effect of suppressing saltiness. "Evaluation results": average evaluation by 11 panelists Control: 3.8 Example: 2.6 (7-2) Anchovy sauce A commercially available anchovy sauce (control) and an anchovy sauce (example) with a koji-based food concentration of 0.5% by mass were prepared by adding the koji-based food obtained in Example 1 to this anchovy sauce, and a sensory evaluation was carried out. For the sensory evaluation, 11 panelists held each of the anchovy sauces from the control and example in their mouths and then swallowed them, and selected the one with the strongest saltiness using a two-point discrimination test. The evaluation results are as follows, and the koji-based food of the present invention was found to have a statistically significant effect (p<0.05) in suppressing saltiness and harshness. "Evaluation results": number of panelists' selections Control: 9 Example: 2

[0049] Example 8 Sensory Evaluation: Spiciness-Sustaining Effect To examine the spiciness-sustaining effect of the koji-based foods of the present invention, a panel conducted the following sensory evaluation. (8-1) Chili Pepper Liquid A chili pepper liquid (control) containing 0.3% (w / v, mass-to-volume ratio percentage) chili pepper extract extracted with water was prepared, and a chili pepper liquid (Example) was prepared by adding the koji-based food obtained in Example 1 to the chili pepper liquid to give a koji-based food concentration of 0.3% (w / v). These were then subjected to a sensory evaluation. For the sensory evaluation, 11 panelists held the chili pepper liquids of the Control and Example in their mouths and then swallowed them. They evaluated the spiciness-sustaining effect using the following 5-point rating system, and the average of the panelists' scores was calculated. "Spiciness-Sustaining Effect" Short 1 2 3 4 5 Long The evaluation results are as follows: A statistically significant difference (p<0.01) was observed for the koji-based foods of the present invention. "Evaluation results": average evaluation by 11 panelists Control: 3.2 Example: 4.3 (8-2) Curry A commercially available curry roux (control) and a curry roux (example) were prepared by adding the koji-based food obtained in Example 1 to this curry roux to make the koji-based food concentration 0.3% by mass, and a sensory evaluation was conducted. For the sensory evaluation, seven panelists held each of the control and example curry roux in their mouths and then swallowed them, and selected the one with the longest-lasting spiciness in a two-point discrimination test. The evaluation results are as follows, and a statistically significant difference (p<0.01) was observed in the koji-based food of the present invention. "Evaluation results": number of panelists' selections Control: 0 Example: 7

[0050] Example 9: Koji-using foods of the second and third embodiments were prepared according to the process shown in Figure 6. However, the classification process was omitted. (1) Koji-using Food of the Second Embodiment The rice koji obtained in Example 1 (1) was heated at 105°C for 2 hours using a steam convection oven (Rational, SelfCooking Center XS) and then dried. The heated rice koji was pulverized using a blender to obtain the desired koji-using food in powder form. 0.78 kg of the koji-using food of the second embodiment was obtained from 1.0 kg of rice koji. (2) Koji-using Food of the Third Embodiment The rice koji obtained in Example 1 (1) was preheated at 60°C for 6 hours using a thermostatic oven (Espec, SH-221), then heated at 105°C for 2 hours using a steam convection oven (Rational, SelfCooking Center XS) and then dried. The heated rice koji was pulverized in a blender to obtain the desired koji-based food product in powder form. 0.85 kg of the koji-based food product of the third embodiment was obtained from 1.0 kg of rice koji. The nutritional information (theoretical values ​​per 100 g) of the resulting koji-based foods of the second and third embodiments is shown in Table 5.

[0051]

[0052] Example 10 Sensory Evaluation: Umami-Lasting Effects To examine the umami-lasting effects of the koji-using foods of the second and third embodiments, panelists conducted a sensory evaluation of the following consommé soup. A commercially available consommé soup (control) and a consommé soup (Example) prepared by adding the koji-using food of the second or third embodiment to this soup to obtain a koji-using food concentration of 1.0% by mass were prepared, and a sensory evaluation was conducted. Nine panelists held each of the control and Example consommé soups in their mouths and then swallowed them, and selected the one with the longest-lasting umami flavor using a two-point discrimination test. The evaluation results are as follows: the koji-using food of the third embodiment exhibited a statistically significant (p<0.05) umami-lasting effect, whereas six panelists selected the koji-using food of the second embodiment, which was more than the three panelists who selected the control, but no statistically significant difference was observed. "Evaluation results": Number of panelists' selections Food using koji of the second embodiment Control: 3 Example: 6 Food using koji of the third embodiment (p<0.05) Control: 1 Example: 8

[0053] Example 11 Sensory Evaluation: Spiciness-Sustaining Effect To investigate the spiciness-sustaining effect of the koji-using food of the third embodiment, panelists conducted a sensory evaluation of the following chili pepper extract. A chili pepper extract (control; chili pepper extract concentration in water: 0.3% by mass) and a chili pepper extract (Example) prepared by adding the koji-using food of the third embodiment to this extract to make the koji-using food concentration 1.0% by mass were prepared, and a sensory evaluation was conducted. For the sensory evaluation, nine panelists held the consommé soups of the control and Example in their mouths and then swallowed them, and selected the one with the longest-lasting spiciness using a two-point discrimination test. The evaluation results are as follows, and a statistically significant difference (p<0.05) was observed for the umami-sustaining effect. "Evaluation Results": Number of panelists' selections: Control: 1 Example: 8

[0054] Example 12: Substances in the koji-using food of the present application were investigated. First, a qualitative analysis was performed on the koji-using food, a sample before the heat-drying process, and rice koji using a gas chromatograph mass spectrometer (GCMS-QP2010 Ultra, manufactured by Shimadzu Corporation). The analysis conditions were as follows, and the resulting graphs are shown in Figure 7. In the figure, A is a graph for the sample of the koji-using food of the first embodiment obtained in Example 1(1) (Example), B is a sample of the pressed cake (before the heat-drying of the koji-using food) obtained in Example 1(2) (Comparative Example), and D is a graph for the rice koji sample obtained in Example 1(1). <Analysis conditions> Solid-phase microextraction (SPME) SPME fiber: 65 μm Stable Flex PDMS / DVB (Supelco 57293-U, manufactured by Merck Life Sciences) Incubation time: 10 minutes Oven: 105°C SPME adsorption time: 5 minutes Desorption time: 1 minute Gas chromatograph Column oven: Maintained at 40°C for 5 minutes. Then, the temperature was increased to 220°C at a rate of 8°C per minute and maintained at 220°C for 5 minutes. Vaporizer temperature: 250°C Column: ZB-WAX-PLUS (60 m, 0.25 mm ID, df = 0.25 m) Carrier gas: Helium Carrier gas control: Constant linear velocity, 31.2 cm / sec Injection mode: Split Mass spectrum Interface: 230°C Ion source: 220°C Measurement mode: Scan Mass range: m / z 20 to 400 Event time: 0.3 sec The peak with a retention time of 18.8 minutes in graph A is not present in graphs B and D. This peak was identified as 3-furaldehyde by the search database: MIST 11 Mass Spectral Library.

[0055] Next, the quantification of 3-furaldehyde contained in the koji-containing foods of the first to third embodiments, the sample before the heat-drying process (pressed cake obtained in Example 1(2)), and the rice koji obtained in Example 1(1) was carried out by headspace gas chromatography mass spectrometry. 2 g of sample was weighed into a 20 mL vial and measured under the following analytical conditions. <Analysis Conditions> Headspace Autoinjector: AOC-5000 Syringe Heater: MSH 02-00B Syringe Size: 2.5 mL Injection Volume: 1.0 mL Incubation Time: 20 minutes Oven: 80°C Syringe Needle Temperature: 80°C Gas Chromatography and Mass Spectrum The gas chromatograph mass spectrometer (Shimadzu Corporation, GCMS-QP2010 Ultra) described above was used, and the conditions were the same. The 3-furaldehyde content in each sample is shown in Table 6.

[0056] "<5" in the table indicates that it was not detected at or below the detection limit (5 ng / g). Similarly, 3-furaldehyde was not detected in any foods made with rice koji, such as commercially available powdered koji. Based on its structure, 3-furaldehyde is thought to be contained as an intermediate product of melanoidin in the Maillard reaction, and is thought to be one of the sources of the umami and rich flavor of foods made with koji.

[0057] Example 13: High-performance liquid chromatography (HPLC) analysis was performed on the koji-based food of the present application using a Nexera (Shimadzu Corporation) to attempt to identify the substances contained therein. HPLC analysis was performed on the koji-based food of the first embodiment obtained in Example 1(1) under the following conditions. <HPLC analysis conditions> Extract: Extracted with water in an amount four times the weight ratio of the analyte. Mobile phase A: 0.1% by mass trifluoroacetic acid aqueous solution. Mobile phase B: acetonitrile. Isocratic conditions: Mobile phase A 95%, mobile phase B 5%. Flow rate: 0.6 mL / min. Column: CAPCELL PAK C18 AQ (Osaka Soda Co., Ltd., 4.6 mm x 100 mm, 3 μm). Detection wavelength: 297 nm. The resulting chromatogram is shown in Figure 8. As shown in Figure 8, two characteristic peaks are observed at retention times of 7.07 minutes (Peak A) and 9.55 minutes (Peak B). The koji-using food of the second embodiment and the koji-using food of the third embodiment also have two similar peaks as shown below. <Peak position: retention time> - koji-using food of the second embodiment: 7.06 minutes, 9.56 minutes - koji-using food of the third embodiment: 7.03 minutes, 9.50 minutes

[0058] (1) Peak A Peak A is a Maillard reaction product of cysteine ​​and glucose, as shown below. The control Maillard reaction product was obtained by heating 1 mole of cysteine, 2 moles of glucose, and 0.2 moles of sodium bicarbonate at 105°C for 2 hours. HPLC analysis, UV spectrum comparison, and LC-MS analysis were performed on the koji-based food and the Maillard reaction product of cysteine ​​and glucose. For the HPLC analysis, the koji-based food of the first embodiment was used as the koji-based food. A water extract of the koji-based food was adsorbed onto an ODS column (a reverse-phase chromatography column packed with a silica gel carrier and a packing material to which octadecylsilyl groups are chemically bonded). A sample eluted with a 10% aqueous ethanol solution was analyzed by HPLC under the same conditions. The Maillard reaction product of cysteine ​​and glucose was adsorbed onto the ODS column and eluted with a 10% aqueous ethanol solution. The HPLC analysis results are shown in FIG. 9 . Figure 9 (a) is an HPLC analysis graph of the koji-based food, and (b) is a graph of the Maillard reaction product of cysteine ​​and glucose. Both graphs show a peak at approximately the same retention time of 3.9 minutes (the peak surrounded by a dotted line). Figure 10 shows a superimposed UV spectrum of the component corresponding to the peak at approximately 3.9 minutes in the two samples. A represents the spectrum of the peak contained in the koji-based food, and C represents the spectrum of the Maillard reaction product of cysteine ​​and glucose. As is clear from Figure 10, the components from the two samples both had the same maximum absorption wavelength of 297 nm in their UV spectra. Furthermore, Figure 11 shows a mass spectrometry graph in the positive ion mode of ESI-MS, obtained by analyzing the components corresponding to the peaks in the two samples using LC-MS. Figure 11 (a) is a graph of the koji-based food of the first embodiment, and (b) is a graph of the Maillard reaction product of cysteine ​​and glucose. Both graphs have a peak at an m / z of approximately 144.9. From the above, it can be seen that the koji-based foods Nos. 1 to 3 contain Maillard reaction products of cysteine ​​and glucose. The Nexera (Shimadzu Corporation) was used as the apparatus for Figures 9 and 10, and the HPLC analysis conditions for Figure 9 were as follows:FIG. 11 is a graph obtained by performing mass analysis of the peaks corresponding to the peaks shown in FIG. 10 using a Waters Alliance (manufactured by Japan Waters) connected to QDa as a detector, and the LC-MS analysis conditions are as follows: <HPLC analysis conditions> Mobile phase A: 0.1% by mass trifluoroacetic acid aqueous solution Mobile phase B: acetonitrile Isocratic conditions: mobile phase A 95%, mobile phase B 5% Flow rate: 1.0 mL / min Column: CAPCELL PAK C18 MGII (Osaka Soda Co., Ltd., 4.6 mm x 100 mm, 3 μm) Detection wavelength: 297 nm <LC-MS analysis conditions> Mobile phase A: 0.1% formic acid Mobile phase B: acetonitrile (containing 0.1% formic acid) Isocratic conditions: mobile phase A 95%, mobile phase B 5% Flow rate: 1.0 mL / min Column: CORTECS C18 (Nihon Waters, 4.6 mm x 150 mm, 2.7 μm) Detector: QDa (scan range m / z 30 to 1250).

[0059] (2) Peak B For the koji-using foods of the first to third embodiments, the retention time of Peak B in HPLC analysis, the relative retention time ratio of Peak B to Peak A (Peak B retention time / Peak A retention time), and the maximum absorption wavelength in the UV spectrum are shown in Table 7. From these results, it is believed that Peak B is the same compound in all of the koji-using foods.

[0060]

[0061] The mass spectrometry graph of the LC-MS analysis in the positive ion mode of ESI-MS is shown in Figure 12. The analyses of peak B were carried out in the same manner as for peak A.

[0062] A: Example, B: Before heating, C: Reference example, 1: Example, 2: Control

Claims

1. The method includes a step of fermenting a mixture containing rice, koji mold, and water, a step of separating the mixture into a solid and a liquid, and a step of heating the solid obtained by separation. A method for producing foods using koji.

2. The method for producing a koji-based food product according to claim 1, wherein the solid is heated at a temperature of 80°C or higher and 140°C or lower.

3. The method for producing a koji-containing food according to claim 1, wherein the solid is heated for 30 minutes or more and 5 hours or less.

4. The method for producing a koji-containing food according to any one of claims 1 to 3, wherein the mixture in the fermenting step is fermented while containing salt.

5. The method for producing a koji-based food product according to claim 4, wherein the mixture is fermented at a temperature of 4°C or higher and 40°C or lower.

6. 5. The method for producing a koji-containing food according to claim 4, wherein the mixture contains water and rice koji, which is made by propagating koji mold on steamed rice.

7. The method for producing a koji-containing food according to any one of claims 1 to 3, wherein the mixture is further fermented in the presence of ethanol.

8. This involves heating the rice koji, which is made by growing koji mold on steamed rice. A method for producing food using koji, The method for producing a food using koji, wherein the food using koji contains 3-furaldehyde.

9. The method for producing a food using koji according to claim 8, wherein the rice koji is heated at a temperature of 80°C or higher and 140°C or lower.

10. The method for producing a food using koji according to claim 8, wherein the rice koji is heated for 30 minutes or more and 5 hours or less.

11. The method for producing a food using koji according to any one of claims 8 to 10, wherein the rice koji is preheated at 50°C or higher and 75°C or lower before the step of heating the rice koji.

12. The method for producing a koji-containing food according to claim 11, wherein the rice koji is preheated for 3 hours or more before the step of heating the rice koji.

13. A dried food product using koji, which contains a fermented decomposition product of rice using koji mold and inactivated koji mold.

14. The koji-based food product according to claim 13, further comprising salt.

15. The koji-based food according to claim 13, which contains 3-furaldehyde.

16. In the koji-containing food, peak A corresponding to a Maillard reaction product of cysteine ​​and glucose is detected in HPLC analysis and LC-MS analysis. The koji-containing food according to any one of claims 13 to 15.

17. The koji-based food further comprises (1) In a chromatograph obtained under the following HPLC analysis conditions, when the retention time of the peak A is taken as 1.0, the peak B has a relative retention time of 1.1 to 1.6, (2) the absorption maximum wavelength of the peak B is 279 nm or more and 289 nm or less; (3) In the mass analysis of the peak B by ESI-MS in positive ion mode, the peak has an m / z of 125.9 or more and 127.9 or less. The koji-containing food according to claim 16. "HPLC analysis conditions" Extraction solution: Extract with water in an amount four times the weight of the analyte. Mobile phase A: 0.1% by mass trifluoroacetic acid aqueous solution Mobile phase B: acetonitrile Isocratic conditions: Mobile phase A 95%, Mobile phase B 5% Flow rate: 0.6mL / min Column: CAPCELL PAK C18 AQ (Osaka Soda Co., Ltd., 4.6 mm x 100 mm, 3 μm) Detection wavelength: 297 nm