Method for producing fermented sweet bean paste

Abstract

To provide a method for producing a fermented sweet bean paste, in which rice koji does not remain in the final product even though rice koji is used, and which can have a texture and taste comparable to those of a conventional ordinary sweet bean paste.SOLUTION: The method for producing a fermented sweet bean paste according to the present invention is characterized in that a sweet bean paste material containing starch gelatinized by heat and a water-permeable filterable sheet enclosing a rice koji therein are heated for a predetermined time while being mixed in the same vessel, the food material is saccharified by the action of enzymes contained in the rice koji, and then the water-permeable filterable sheet is taken out, thereby obtaining a fermented food to which sweetness and umami due to the rice koji are added.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method for producing fermented bean paste that uses rice koji but does not leave any rice koji in the finished product, and that has a texture and flavor comparable to those of traditional ordinary bean paste. [Background technology]

[0002] Anko (red bean paste) is a well-known ingredient in Japanese sweets. In addition to that made from azuki beans, a wide variety of anko has long been made and widely eaten using white kidney beans, adzuki beans, pinto beans, sweet potatoes, chestnuts, and other ingredients.

[0003] Although it is a very familiar food for Japanese people, bean paste is very high in carbohydrates because it is basically made by cooking starchy ingredients with sugar. As excessive carbohydrate intake can have adverse effects on health, in recent years various attempts have been made to reduce the amount of carbohydrates contained in bean paste.

[0004] One such attempt is "fermented bean paste," which is actually being produced. Fermented bean paste is made by using rice koji instead of sugar to create sweetness. The enzymes contained in the rice koji saccharify (ferment) the azuki beans, allowing for a significant reduction in the amount of sugar used, or even no sugar at all, while still bringing out the sweetness and umami of the azuki beans.

[0005] However, this type of fermented bean paste has the drawback that rice koji remains in the finished product. Compared to red beans, rice koji itself has almost no umami flavor, so the remaining rice koji not only reduces the flavor of the fermented bean paste, but also affects its smoothness and makes it feel unpleasant to the touch.

[0006] The present inventors have conducted extensive research to solve the problems described above, and as a result have discovered that the problems described above can be solved by a method for producing fermented bean paste, in which food materials containing starch gelatinized by heating and a water-permeable filter sheet encasing rice koji are mixed in the same container and heated for a predetermined period of time, the food materials are saccharified by the action of enzymes contained in the rice koji, and the water-permeable filter sheet is then removed. Based on this finding, the present invention was created.

[0007] In addition, when filing the application for the present invention, the applicant (inventor) of the present application searched past patent documents, etc., and was able to find the following documents in the technical field to which the present invention pertains, but was unable to find any patent documents that detailed the technical ideas, etc., related to the present invention. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-282529 [Patent Document 2] Japanese Patent Publication No. 2022-180760 Summary of the Invention [Problem to be solved by the invention]

[0009] To provide a method for producing fermented bean paste which uses rice koji but does not leave any rice koji in the finished product and has texture and flavor comparable to those of traditional ordinary bean paste. [Means for solving the problem]

[0010] As a means for achieving this, the method for producing fermented bean paste according to the present invention is characterized in that ingredients containing starch gelatinized by heating and a water-permeable filter sheet encasing rice koji are mixed in the same container and heated for a predetermined period of time, the ingredients are saccharified by the action of enzymes contained in the rice koji, and then the water-permeable filter sheet is removed, thereby obtaining fermented bean paste infused with the sweetness and umami of the rice koji.

[0011] The method for producing fermented bean paste according to the present invention is also characterized in that it includes a step of adding mirin after saccharification of the ingredients.The method for producing fermented bean paste according to the present invention is also characterized in that the ingredients containing starch gelatinized by heating are adzuki beans and / or bleached bean paste gelatinized by heating.

[0012] Furthermore, the method for producing fermented bean paste according to the present invention is characterized in that the container used to heat the ingredients and water-permeable filter sheet while mixing them has the function of automatically rotating and the function of maintaining the temperature inside the container at a constant temperature range.

[0013] The method for producing fermented bean paste according to the present invention is also characterized in that the water-permeable filtering sheet is heat-sealed at its inner side. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a method for producing fermented bean paste that uses rice koji but does not leave any rice koji in the finished product, and that has a texture and flavor comparable to those of traditional ordinary bean paste. [Brief explanation of the drawings]

[0015] [Figure 1] Schematic diagram showing an example of an embodiment of a bag-shaped water-permeable filtering sheet. [Figure 2] Schematic diagram showing an example of an embodiment of a bag-shaped water-permeable filtering sheet. [Figure 3] Schematic diagram showing an example of an embodiment of a bag-shaped water-permeable filtering sheet. DETAILED DESCRIPTION OF THE INVENTION

[0016] Hereinafter, as an embodiment for carrying out the method for producing fermented bean paste according to the present invention, a method for producing fermented bean paste (tsubuan) using adzuki beans as a starch-containing ingredient will be described.

[0017] First, prepare raw azuki beans and the same weight of rice koji. The raw beans are boiled in an appropriate amount of water to soften them, making boiled azuki beans. The rice koji is placed in small portions inside a water-permeable filter sheet configured in the shape of a bag, as shown in Figure 1. The opening of this water-permeable filter sheet is then closed to prevent the rice koji from leaking out.

[0018] Any permeable filtering sheet can be used as long as it allows water to pass through while blocking the solid content of rice koji. These are generally sold under the names of tea bags and dashi packs. Note that the permeable filtering sheet is not limited to nonwoven fabrics, and any material, such as woven fabric, paper, or film, can be used as long as it has the above-mentioned functionality.

[0019] When dividing the rice koji into smaller portions, it is preferable to keep the amount of rice koji in each bag within the range of 20g to 80g. This is because if the amount is less than 20g, the amount is too small, requiring a large amount of bag-shaped water-permeable filter sheet. On the other hand, if the amount is more than 80g, the amount in one bag is too large, causing the rice koji to form clumps, which may prevent the enzymes from functioning properly and result in insufficient saccharification.

[0020] Furthermore, the method for dividing the rice koji into small portions and sealing them in a bag-shaped water-permeable filter sheet is not particularly limited, and any conventional technique can be used as appropriate, as long as it can prevent the rice koji from leaking out of the water-permeable filter sheet. However, considering convenience, heat sealing using a heat sealer is considered optimal. The shaded area in Figure 1 indicates the heat-sealed area.

[0021] Next, the boiled azuki beans and the water-permeable filter sheet with the rice koji inside sealed inside are placed in the same container, and water equivalent to 1.3 to 1.5 times the weight of the rice koji is added. After the water is added, the container is covered and the contents are continuously stirred in the container while heating to maintain the temperature within the range of 58 to 62°C. By heating and stirring in this state, the boiled azuki beans are saccharified by the action of the enzymes contained in the rice koji. The time required for saccharification depends on the condition of the azuki beans and the surrounding environment, but is expected to be around 6 to 10 hours.

[0022] It is preferable to use an electric cooking pot as a container for continuously mixing while heating as described above. In particular, it is particularly preferable to use an electric cooking pot that has a heating (heat retention) function and a function of rotating around an inclined axis from the viewpoint of convenience.

[0023] Once saccharification is complete, stop heating, open the container lid, and remove all of the water-permeable filter sheets. Then, with the lid removed, boil the mixture at a temperature between 105 and 115°C while evaporating the water until it is soft enough to be used as tsubuan (fried bean paste). The boiling time required to obtain fermented bean paste (tsubuan) is estimated to be around 40 to 60 minutes.

[0024] The sugar content of the fermented bean paste obtained in this way is about 30 to 35, which is quite moderate for bean paste. Therefore, the fermented bean paste obtained here allows you to feel the flavor of the red beans themselves, and is more suitable for use as an ingredient in cooking than in Japanese sweets.

[0025] By adding a predetermined amount of mirin to this fermented bean paste, it is possible to obtain bean paste with a sweetness (sugar content) suitable for use as an ingredient in Japanese sweets, etc. For convenience, this bean paste with added mirin will be referred to as "fermented mirin bean paste" hereinafter in this specification.

[0026] When producing fermented mirin bean paste, mirin is added at the stage of boiling down the bean paste after all the water-permeable filter sheets have been removed. The weight of mirin added is preferably equivalent to 80 to 90% of the weight of the raw adzuki beans used as the raw material.

[0027] In the above embodiment, raw adzuki beans are used as the starch-containing ingredient, but bleached bean paste can also be used. If bleached bean paste is used, fermented smooth bean paste can be produced. Of course, it is also possible to obtain fermented smooth bean paste by adding a step of straining the fermented smooth bean paste after obtaining it.

[0028] Furthermore, as long as the food material contains starch, it is possible to use other foods besides adzuki beans, such as beans such as white kidney beans, adzuki beans, pinto beans, as well as sweet potatoes and chestnuts, etc. Furthermore, the present invention is not limited to these, and any food material can be used as long as it contains starch and is gelatinized by heating.

[0029] In addition, as for the bag-shaped water-permeable filter sheet for containing rice koji described in the above embodiment, in addition to the one shown in FIG. 1, those having the configurations shown in FIGS. 2 and 3 can also be used.

[0030] Figures 2 and 3 show bag-shaped water-permeable filter sheets that can hold larger amounts of rice koji than those in Figure 1. If more rice koji is placed in one bag-shaped water-permeable filter sheet, the labor required for dividing it into smaller portions is reduced, simplifying the manufacturing process.

[0031] However, when using the bag-shaped water-permeable filter sheets shown in Figures 2 and 3, it is possible that the size will increase and the shape of the bag will be easily damaged. To avoid this, when using these, it is preferable to place the four masses of rice koji near the four corners of the bag, and then use a heat sealer to heat-seal the inside of the bag in a cross shape as shown by the shaded area in Figure 2, or to heat-seal the inside of the center of the bag as shown by the shaded area in Figure 3. [Example]

[0032] Next, the present invention will be described in more detail with reference to the following examples.

[0033] [Preparation] Koji products ("Rice flour koji" made by Ikedaya Brewing Co., Ltd. (Kumamoto Prefecture)) Commercially available tea bags Electric cooking pot (with heating (keep warm) and tilting axis rotation functions)

[0034] [Example 1: Fermented bean paste (tsubuan)] First, 300g of boiled azuki beans were prepared by boiling them in an appropriate amount of water until soft. Ten tea bags were prepared, each containing 300g of rice koji in small portions, and the openings were sealed with a heat sealer to prevent the rice koji from leaking outside the tea bags. Next, the prepared boiled azuki beans and tea bags were placed in an electric cooking pot, and 400cc of water was added.

[0035] The electric cooking pot was covered and the temperature was set to 60°C. The pot was then rotated with its axis tilted, and cooking was carried out for 8 hours to saccharify (ferment) the azuki beans. After 8 hours had passed, the lid was removed and the tea bag was taken out, then the temperature was set to 110°C and the beans were boiled for 45 minutes to remove the water and reach the desired softness, yielding fermented bean paste (tsubuan).

[0036] When the resulting fermented bean paste (tsubuan) was tasted, it was found to have a texture and flavor comparable to that of conventional low-sugar bean paste. It was hard to believe that it was made without added sugar.

[0037] [Example 2: Fermented mirin bean paste (tsubuan)] First, 300g of boiled azuki beans were prepared by boiling them in an appropriate amount of water until soft. Ten tea bags were prepared, each containing 300g of rice koji in small portions, and the openings were sealed with a heat sealer to prevent the rice koji from leaking outside the tea bags. Next, the prepared boiled azuki beans and tea bags were placed in an electric cooking pot, and 400cc of water was added.

[0038] The electric cooking pot was covered and the temperature was set to 60°C. The pot was then rotated with its axis tilted, and cooking was carried out for 8 hours to saccharify (ferment) the adzuki beans. After 8 hours had passed, the lid was removed and the tea bag was taken out. 250cc of mirin was added, the temperature was set to 110°C, and the mixture was boiled down for 45 minutes to remove the water and reach a suitable softness, yielding fermented mirin bean paste (chuan paste).

[0039] When the resulting fermented mirin bean paste (tsubuan) was tasted, it was found to have a texture and flavor comparable to that of conventional bean paste. It was also sufficiently sweet that it was hard to tell that it was bean paste made without added sugar.

[0040] [Example 3: Fermented bean paste (koshian)] First, 300g of bleached bean paste was prepared. Also, 10 tea bags were prepared, and 300g of rice koji was placed in each bag. The openings were sealed with a heat sealer to prevent the rice koji from leaking outside the tea bags. Next, the prepared bleached bean paste and tea bags were placed in an electric cooking pot, and 1200cc of water was added.

[0041] The electric cooking pot was covered and the temperature was set to 60°C. The pot was then rotated with its axis tilted, and cooking was carried out for 8 hours to saccharify (ferment) the sashi-an. After 8 hours had passed, the lid was removed and the tea bag was taken out. The temperature was then set to 110°C and the mixture was boiled down for 45 minutes to remove the water and achieve the desired softness, yielding fermented bean paste (smooth bean paste).

[0042] When the resulting fermented bean paste (smooth bean paste) was tasted, it was found to have a texture and flavor comparable to that of conventional low-sugar bean paste. It was hard to believe that it was made without added sugar.

[0043] [Example 4: Fermented mirin bean paste (koshian)] First, 300g of bleached bean paste was prepared. Ten tea bags were also prepared, and 300g of rice koji was placed in each bag. The openings of the tea bags were sealed with a heat sealer to prevent the rice koji from leaking outside. Next, the boiled bleached bean paste and tea bags were placed in an electric cooking pot, and 1200cc of water was added.

[0044] The electric cooking pot was covered and the temperature was set to 60°C. The pot was then rotated with its axis tilted, and cooking was carried out for 8 hours to saccharify (ferment) the sashimi bean paste. After 8 hours had passed, the lid was removed and the tea bag was taken out. 250cc of mirin was added, the temperature was set to 110°C, and the mixture was boiled down for 45 minutes to remove the water and achieve the desired softness, yielding fermented mirin bean paste (smooth bean paste).

[0045] When the resulting fermented mirin bean paste (smooth bean paste) was tasted, it was found to have a texture and flavor comparable to that of conventional bean paste. It was also sufficiently sweet, and it was hard to tell that it was bean paste made without added sugar. [Industrial Applicability]

[0046] According to the present invention, it is possible to provide a method for producing fermented bean paste that uses rice koji but does not leave any rice koji in the finished product, and that has a texture and flavor comparable to those of traditional ordinary bean paste.

Claims

1. This method for producing fermented bean paste is characterized by mixing ingredients containing starch gelatinized by heating with a water-permeable filter sheet encasing rice koji inside in the same container and heating for a predetermined time, saccharifying the ingredients by the action of enzymes contained in the rice koji, and then removing the water-permeable filter sheet, thereby obtaining fermented bean paste that is infused with the sweetness and umami of the rice koji.

2. 2. The method for producing fermented bean paste according to claim 1, further comprising the step of adding mirin after saccharification of the ingredients.

3. 2. The method for producing fermented bean paste according to claim 1, wherein the food material containing starch gelatinized by heating is adzuki beans gelatinized by heating and / or bleached bean paste.

4. 4. The method for producing fermented bean paste according to claim 3, wherein the container used for heating the food material and the water-permeable filter sheet while mixing them has an automatic rotation function and a function for maintaining the temperature inside the container at a constant temperature range.

5. 5. The method for producing fermented bean paste according to claim 4, wherein the water-permeable filtering sheet is heat-sealed at its inner side.

Images