JP2003000176A - Method for fermentation in fermented soybeans and circulation ventilation type fermentation chamber in fermented soybeans - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide both a method for fermented soybeans production, with which high-quality and uniform fermented soybeans can be produced by more uniformizing a temperature of fermented soybeans stored in a container and a fermentation progress and a circulation ventilation type fermentation chamber in fermented soybeans suitable for fermenting soybeans. SOLUTION: In this circulation ventilation type fermentation chamber, the average air velocity of circulation ventilation is 0.5 m/s to 1 m/s and an average temperature difference between an inlet part and an outlet part of a container housing chamber is <=3 deg.C to ferment soybeans. The circulation ventilation type fermentation chamber suitable therefor is provided with two independent container housing chambers and two independent air-conditioned air circulation ventilation systems.

Description

Detailed Description of the Invention

[0001]

[Field of Industrial Application] The present invention improves the fermentation temperature of fermented soybeans by using a circulating-ventilated fermented soybeans to make the temperature of the stored fermented soybeans more uniform and to improve the fermentation rate. The present invention relates to a method for producing natto to enable production of natto of uniform quality, and a circulating draft type natto fermentation chamber suitable for fermenting natto by the production method.

[0002]

2. Description of the Related Art In general, natto is manufactured by immersing raw soybeans in water for a predetermined time and then steaming them under a predetermined pressure, inoculating the steamed soybeans with natto bacterium and putting them in a predetermined natto container. Have been stored in a container, the containers are stacked in multiple stages, placed in a fermentation chamber, and fermented under predetermined conditions.

A conventional natto fermentation chamber is disclosed in Japanese Patent Laid-Open No. 4158/1992.
As described in Japanese Patent No. 6 or the like, containers are simply stacked in a natto fermentation chamber, and an air conditioning unit having an air conditioning function and a downward fan is installed on the ceiling of the fermentation chamber. In general, the temperature of the soybeans in the natto containers stacked in a large number in the container is adjusted by blowing air.

In such a conventional natto fermentation room,
The air blower fan of the air conditioning unit blows air to the center and sides of the fermentation chamber.However, in the natto fermentation chamber, a large number of containers containing a large number of natto containers are stacked, and the ventilation resistance of these containers is increased. There was a problem that ventilation could not be performed properly. In addition, a large amount of heat is generated during the period when fermentation of natto bacteria is vigorous, so cooling is necessary, and at that time, the cooling air blown out from the air conditioning unit is particularly likely to flow to the lower part of the natto fermentation chamber. It was difficult to keep the room temperature uniform in the natto fermentation room. For example, it has been confirmed that there is a temperature difference of 5 to 6 ° C. in the air between the lower part and the upper part of the natto fermentation chamber at the time when fermentation is most active in the conventional natto fermentation chamber. As a result, it was difficult to make the product temperature of each natto container uniform, and it was difficult to manufacture natto of good quality and uniform quality.

In order to improve these drawbacks of the conventional natto fermentation chamber, the natto fermentation chamber is divided into a container accommodating chamber and a circulation ventilation chamber, and the circulation ventilation chamber is equipped with an air conditioning function and a blower fan at the ceiling. An air conditioning unit is provided, and a straightening vane having a plurality of through holes is provided on both left and right sides of the container storage chamber. Various devices have been devised (Japanese Patent Laid-Open Nos. 1-174352 and 5)
-276890, JP-A-10-136923, etc.).

FIG. 4 is a side sectional view showing the construction of an example of the circulating ventilation type natto fermentation chamber as described above. As shown in the figure, inside the natto fermentation chamber 10, there is installed a container storage chamber 18A partitioned by a ceiling plate 12A and side walls 14A and 14B, and the container storage chamber 18A is steamed. The container containing the natto container 25 containing soybeans has a plurality of rows in a horizontal direction (four rows (24a, 24a, 24a in the illustrated example.
(b, 24c, 24d)), the required number (for example, 15 steps) can be stacked and stored on the gantry 17, and the required number of containers (for example, 8 rows) can be stored in the depth direction. There is. The container housing chamber 18A has openings 14a and 14b whose both ends are open, and the opening has openings 14a and 14b for rectifying the flow velocity of the air flowing through the interior of the container.
a and 15b are installed.

The ceiling plate and the side wall of the natto fermentation chamber 10,
Ceiling plate 12A and side wall 14A of container storage chamber 18A,
A space for circulating ventilation is formed between the space 14B and 14B, and this space is divided by the partition wall 13 into two circulation ventilation chambers 16A and 16B. An air conditioning unit 22A is installed on the ceiling so as to penetrate the partition wall 13.

The air conditioning unit 22A is composed of a cooler 22a, a heater 22b, a humidity controller 22c, a blower fan 23, and the like. The outside air introduced from the outside air inlet 22i and the suction port 22e from the circulation ventilation chamber 16A. The air that has been sucked in is adjusted to a predetermined temperature and a predetermined humidity, and the air outlet 22d is adjusted.
It can be supplied to the circulation ventilation chamber 16B.
Further, a control means for switching the direction of circulating ventilation at a predetermined interval is provided so that the blower fan 23 is reversed and air is sucked from the circulating ventilation chamber 16B into the air conditioning unit 22A and can be supplied to the circulating ventilation chamber 16A after air conditioning. There is. In this circulating-ventilation type natto fermentation chamber 10, even if the directions of circulating ventilation are two directions of forward and reverse, there is only one system of circulating ventilation.

In the conventional circulation ventilation type natto fermentation chamber 10 having the above-described structure, when the air conditioning unit 22A is operated, the conditioned air adjusted to a predetermined temperature and humidity is supplied into the container accommodating chamber 18A, and the air conditioning is performed. The air absorbs the heat of fermentation generated from natto during fermentation. The conditioned air that has absorbed the heat of fermentation flows out from the outlet of the container storage chamber 18A, is readjusted to a predetermined temperature and humidity by the air conditioning unit 22A, and then supplied again into the container storage chamber 18A. That is, the fermentation of natto is promoted and produced by circulating ventilation of conditioned air.

Since the conditioned air supplied into the container storage chamber 18A absorbs the heat of fermentation in the process of passing through the container storage chamber 18A, the temperature of the conditioned air on the outlet side of the container storage chamber 18A is equal to the temperature on the inlet side. Will be higher than. Due to the difference in temperature, the product temperature of natto tends to vary between the outlet side and the inlet side in the container storage chamber 18A, and in order to manufacture high quality and uniform natto, the temperature deviation of the conditioned air is required. Should be within a predetermined range. Therefore, the size of the container storage chamber 18A, and consequently the number of containers stored in the container storage chamber, is naturally limited.

If, for example, the production amount in the fermentation chamber of the form shown in FIG. 4 is doubled (the scale of the number of containers stored is doubled), the volume of the container storage chamber 18A is simply doubled. However, since only one circulation ventilation system is provided, that is, the entire amount of conditioned air passes through all the containers accommodated in the container accommodating chamber 18A in succession, the temperature deviation of the conditioned air described above. Since it is not possible to store the natto in a predetermined range at the entrance and the exit, it is impossible to manufacture a uniform natto. For that purpose,
In order to double the size, it is necessary to add another new fermentation chamber of the same shape and size, and equipment cost,
Maintenance costs are high, and the installation space must be large.

On the other hand, when fermenting natto using the circulating ventilation type natto fermenting chamber as described above, in order to produce high quality and uniform natto, as described above, the temperature deviation in the container accommodating chamber is appropriately maintained. At the same time, it is said that it is necessary to make the circulating air flow at an appropriate speed, but research from this point of view is still insufficient, and the above-mentioned Japanese Patent Laid-Open Publication No. Hei 5 (1999) -242242 is referred to.
In the publication No. 276890, it was reported that the production rate was high when the temperature difference between the upper and lower shelves was about 3 ° C., but there was no analysis in relation to the wind speed of the circulating draft, and Kaihei 10-136923 discloses that the air velocity of circulating ventilation is set to about 0.6 m / s to 1.8 m / s, but no analysis is made from the relationship with the temperature difference.

[0013]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and a first object is to optimize fermentative production of natto of higher quality and uniform quality. The second purpose is to improve fermented fermented fermented natto fermented fermented fermented fermented soybeans that can produce a large amount of good quality and uniform quality fermented soybeans efficiently and at low cost. To provide a room.

[0014]

Means for Solving the Problems In order to find a fermentation condition capable of fermenting natto of higher quality and uniform quality, the present inventors have used a circulating-ventilated natto fermentation chamber of the form shown in FIG. Through many experiments and studies, the optimum average wind speed of circulating draft and its optimum average temperature difference were found, and the present invention was completed.

That is, the present invention is a method for fermenting natto using a circulating-ventilation type natto fermenting chamber, in which the average wind speed of circulating ventilation is 0.5 m / s to 1.0 m / s, and the container is housed with circulating ventilation. The average temperature difference between the room inlet and outlet is 3 ° C
The present invention relates to a method for producing natto characterized by being within the range.

In the present invention, if the average wind speed of the circulating ventilation exceeds 1.0 m / s, the natto will dry and the soybean will be colored black, so that the quality that can be provided to the consumer cannot be secured. Further, the average wind speed of circulating ventilation is 0.
When it is less than 5 m / s, the ability to take away the fermentation heat is insufficient, the variation in the fermentation index value becomes large, and especially natto in the part where the product temperature becomes high becomes overfermented and an ammonia odor is generated, We cannot secure the quality that satisfies consumers.

In the present invention, if the average temperature difference between the circulating air between the inlet and the outlet of the container storage chamber is about 3 ° C. or less, it can be suppressed within the variation of the fermentation index value that cannot be achieved in the conventional fermentation chamber. It is possible to produce high quality natto. However, when the average temperature difference is about 4 ° C. or more, variations in the fermentation index value become large, and a large amount of poor quality natto occurs. The best fermentation is possible within an average temperature difference of about 2 ° C.

In addition, the circulation ventilation type natto fermentation chamber according to the present invention, which can effectively carry out the method for producing natto described above, has the first and second container accommodating chambers 18A in which both ends are opened in the fermentation chamber 10. , 18B are arranged facing each other,
A first circulation ventilation chamber 16A that communicates with both of the opposing openings 14b and 14c of the first and second container storage chambers 18A and 18B, and a first circulation ventilation chamber 16A that communicates with the other open portion 14a of the first container storage chamber 18A. The second circulation ventilation chamber 16B and the third opening communicating with the other opening 14d of the second container storage chamber 18B
A circulation ventilation chamber 16C is formed, and further includes first and second air conditioning units 22A and 22B that communicate one side with the first circulation ventilation chamber 16A.
The other side of A communicates with the second circulation ventilation chamber 16B, and the other side of the second air conditioning unit 22B communicates with the third circulation ventilation chamber 16C, whereby the fermentation chamber has a "first container accommodation chamber". 18A-first circulation ventilation chamber 16A-first air conditioning unit 22A-second circulation ventilation chamber 16B-first container accommodating chamber 18A ", and a" second ventilation air circulation system ". Container accommodation chamber 18B-first circulation ventilation chamber 1
6A-second air conditioning unit 22B-third circulation ventilation chamber 16
C-second container housing chamber 18B "
The air-conditioning air circulation ventilation system is formed, and further, it is provided with control means for switching the ventilation directions of the first and second air-conditioning air circulation ventilation systems at predetermined intervals.

According to the above circulation ventilation type natto fermentation chamber, the natto containers accommodated in the fermentation chamber are divided into two container accommodating chambers, and each container accommodating chamber has a first container and a first container. The conditioned air is sent by two substantially independent conditioned air circulation ventilation systems. Therefore, in the case of the same production volume, the average temperature difference between the inlet and outlet of each container storage chamber of circulating ventilation can be made smaller than that of the conventional circulating ventilation type natto fermentation chamber. It is possible to efficiently and efficiently produce high quality and uniform quality natto.

Further, it is relatively easy to arrange each container accommodating chamber or air conditioning unit so that the first and second independent air-conditioning air circulation ventilation systems are formed in one fermentation chamber (building). Yes, even in the case of doubling the production volume, the equipment cost and maintenance cost can be significantly reduced compared to the case where another new fermentation chamber of the same shape and size is added as in the past. Also, the installation space can be saved.

[0021]

DETAILED DESCRIPTION OF THE INVENTION

[0022]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited thereto. Example 1 (Selection of Average Velocity of Circulating Ventilation) 240 kg of dried whole soybean (very small grain) was washed with water, immersed in 700 L of cold water at about 17 ° C. for 10 hours, then placed in a steaming pot and steamed under pressure (2 kg. / Cm ² , 133 ° C). After completion of the pressure steaming, commercially available Bacillus subtilis natto was inoculated so as to be about 10 ³ per 1 g of steamed soybean. About 50 g of the steamed soybeans inoculated with this natto fungus were filled in a 99 mm square Styrofoam natto container by a filling machine, and then 50 natto containers filled with the steamed soybean inoculated with natto bacteria were 49 per container.
Stores one by one (7 x 7), and then this container 1
A container accommodating chamber 18 in the circulation ventilation type natto fermentation chamber 10 shown in FIG. 4 in which five units are stacked as a basic unit (one row).
Housed in A. In addition, the circulation ventilation type natto fermentation room 10 of FIG.
A maximum of 4 rows (24a to 24d) can be accommodated in each of the above-mentioned containers stacked in 15 stages, but in this embodiment, they are accommodated in 2 rows (24a, 24b).

Fermentation was carried out by reversing the normal and reverse circulation ventilation at a temperature (40 ° C.) and humidity (90%) according to a conventional method at intervals of 5 minutes. In this case, the air conditioning ventilation unit 22A was used.
Fermentation fan 23 was adjusted to set 5 test plots in which the average wind speed of circulating ventilation was changed in 5 steps, and fermented.

The average wind speed of circulating ventilation in each test section is the result shown in Table 1. Note that the average wind speed of the circulating draft is 6 at the inlet and outlet of the container storage chamber, 3 at the bottom, 3 in the middle, and 3 at the top. Anemomaster anemometer: Kanomax Japan Made, model 6
011) is the average value of the wind speed measured.

[0025]

[Table 1]

After fermenting under such conditions for 20 hours,
Remove the natto container stored in the container from the fermentation chamber,
Then, it was stored in a aging chamber at 4 ° C., aged for 2 days, and then taken out. Then, all the natto containers stored in the uppermost container, the middle container, and the lowermost container of the container accommodating chamber were taken out and opened, and the natto inside was evaluated, and the results are summarized in Table 3. In addition, the evaluation evaluated the quality of the natto in a natto container by the fermentation index value classified into 1-10 grades like Table 2, and measured the variation degree by the range of a fermentation index value.

[0027]

[Table 2]

When natto produced by a conventional method in a conventional fermenting room generally used in the natto industry is evaluated, a fermenting index value range of about 4 to 8 is produced according to the above evaluation criteria. Those with a fermentation index value of 5 to 6 are natto that can be eaten deliciously. Further, those having a fermentation index value of 4 or less have no flavor of natto and have a very weak stringing, which is a quality problem. Further, if the fermentation index value is 7 or more, natto will not last for a long time, and an ammonia odor will be felt, which is a quality problem. The above test results are summarized in Table 3.

[0029]

[Table 3]

As a result, the average wind speed of circulating ventilation is 1.0.
When it was higher than m / s, the natto dried and the soybean was colored black so that the quality that could be provided to the consumer could not be secured. The average wind speed of circulating ventilation is 0.5m.
If it is less than / s, the ability to take away the heat of fermentation is insufficient, and the variation in the fermentation index value becomes large, and especially natto in the part where the product temperature is high becomes overfermented and produces an ammonia odor. , It was not possible to ensure the quality that would satisfy consumers. As a result of the above, it was concluded that the average wind speed of circulating ventilation is 0.5 m / s to 1.0 m / s in an appropriate range.

Example 2 (Selection of Average Temperature Difference of Circulating Ventilation) A container containing a natto container filled with steamed soybeans inoculated with natto bacterium prepared by the same method as in Example 1 has 15 stages. The stacked ones were stored as a basic unit (one row) in a container storage chamber 18A in the circulation ventilation type natto fermentation chamber 10 shown in FIG.

In this embodiment, as shown in Table 4, the number of rows of the containers is set to 1 (24a) and 1.5 (24a) in the circulating ventilation type natto fermenting chamber 10 as shown in Table 4. And 2
4b 7 stages), 2 rows (24a, 24b), 3 rows (24a,
24b, 24c) and four rows (24a, 24b, 24c,
24d), and the average temperature difference of circulating ventilation is 1 ° C to
Five test plots were set by preparing so as to vary between 6 ° C. Fermentation is carried out according to the usual temperature (40 ℃) and humidity (90
%), And the circulating air flow in the forward and reverse directions was reversed at intervals of 5 minutes, and the average wind speed was 0.8 m / s. The average wind speed is the average value of the wind speed of the circulating draft measured by the same method as in Example 1.

Further, in this example, the average temperature difference between the circulating ventilation air at the inlet and outlet of the container storage chamber 18A of these five test sections was measured. The average temperature difference is the difference between the average temperature of the circulating ventilation air at the inlet and the average temperature of the circulating ventilation air at the outlet measured by installing a thermometer at the same location as when measuring the wind velocity of the circulating ventilation. .

In addition, in order to obtain the difference in product temperature in the natto container in each test area, the product temperature at the top, middle, and bottom of the inlet and outlet of the container storage chamber 18A is set to the natto container 25.
A thermometer was inserted into the inside for measurement, and the difference between the average product temperature at the three inlet portions and the average product temperature at the three outlet portions was determined to obtain the average product temperature difference.

[0035]

[Table 4]

After fermenting in this manner, the natto container stored in the container was taken out of the fermentation chamber and then at 4 ° C.
It was stored in the aging chamber of No. 2 and aged for 2 days, and then taken out. Then, all the natto containers stored in the uppermost container, the middle container, and the lowermost container in the container storage chamber were taken out and opened, and the natto was evaluated. The evaluation was performed in the same manner as in Example 1. The above results are summarized in Table 5.

[0037]

[Table 5]

As a result of the above, if the average temperature difference between the circulating air at the inlet and the outlet of the container storage chamber is about 3 ° C. or less, it can be suppressed within the variation of the fermentation index value that cannot be achieved in the conventional fermentation chamber. It has been confirmed that high quality natto with a fermentation index value of about 5 to 6 can be produced. On the other hand, when the average temperature difference is about 4 ° C. or more, variations in the fermentation index value become large, and natto of poor quality often occurs, which is not preferable. The most excellent fermentation was possible within an average temperature difference of about 2 ° C.

[Third Embodiment] (Regarding Circulating Ventilation Type Natto Fermentation Chamber) Next, a preferred embodiment of the natto fermentation chamber according to the present invention will be described with reference to the accompanying drawings. FIG. 1 is a partially cutaway perspective view showing a first embodiment of a natto fermentation chamber according to the present invention. 2 is a vertical sectional view taken along line LL in FIG. 1, and FIG. 3 is a horizontal sectional view taken along line HH in FIG.

As shown in the figure, in this example, the natto fermenting chamber 10 is of a box type as a whole, and a first container accommodating chamber 18A formed by a ceiling wall 12A and side walls 14A and 14B is formed therein. And two container accommodating chambers of the second container accommodating chamber 18B formed by the ceiling wall 12B and the side walls 14C and 14D are provided side by side with a predetermined distance. The side walls 14A and 14B of the first container storage chamber 18A have openings 14a and 14b having a size substantially corresponding to the container storage portion, and the side walls 14C and 14D of the second container storage chamber 18B have similar openings. It has 14c and 14d. Then, between the first and second container accommodating chambers 18A and 18B, facing openings 14b and 1 of the first and second container accommodating chambers 18A and 18B are provided.
4c so as to communicate with both sides of the first circulation ventilation chamber 16
A is formed. Reference numeral 19 is an opening / closing door provided at the container loading / unloading port.

Between the ceiling wall of the natto fermentation chamber 10 and the ceiling wall 12A of the first container storage chamber 18A, and between the side wall of the natto fermentation chamber 10 and the opening 14a in the side wall 14A of the container storage chamber 18A, Two circulation ventilation chambers 16B are formed, and further between the ceiling wall of the natto fermentation chamber 10 and the ceiling wall 12B of the second container storage chamber 18B and between the natto fermentation chamber 10
A third circulation ventilation chamber 16C is formed between the side wall of the container and the opening 14a in the side wall 14D of the container storage chamber 12B.

On the ceiling of the first circulation ventilation chamber 16A, a plurality of blower fans 23 having suction ports 23a are installed in the depth direction at substantially constant intervals, and above the blower fan 23. A first air conditioning unit 22A and a second air conditioning unit 22B are installed so that one of them communicates with the first circulation ventilation chamber 16A. And
The other side of the first air conditioning unit 22A has the second circulation ventilation chamber 1
6B, and the other side of the second air conditioning unit 22B communicates with the third circulation ventilation chamber 16C. As a result, in the fermentation chamber 10, the “first container storage chamber 18A
-First circulation ventilation chamber 16A-First air conditioning unit 22A-
Second circulation ventilation chamber 16B-first container storage chamber 18A "
And a first air-conditioning air circulation ventilation system formed by the following: "second container accommodation chamber 18B-first circulation ventilation chamber 16A-second air conditioning unit 22B-third circulation ventilation chamber 16C-second container accommodation" Two air-conditioning air circulation ventilation systems, which are the second air-conditioning air circulation ventilation system formed by the chamber 18B "are formed.

The air conditioning units 22A and 22B are the cooler 2
2a and 22e, heaters 22b and 22f, and humidity controllers 22c and 22g. Then, according to the rotation direction of the blower fan 23, the outside air introduced from the outside air inlet 22i and the air sucked from the first circulation ventilation chamber 16A through the inlet 23a are adjusted to a predetermined temperature and humidity, respectively. From the air outlets 22d and 22h to the second circulation ventilation chamber 16B and the third circulation ventilation chamber 16C, and the air in the second circulation ventilation chamber 16B and the third circulation ventilation chamber 16C. From the suction port 23a through the air conditioning units 22A and 22B to the first circulation ventilation chamber 1
It is possible to switch to the reverse circulation flow that circulates to 6A.

Each opening 14a, 14b, 14c, 14d
In the first container container chambers 18A and 18B, preferably, as shown in the figure, there are installed rectifying plates 15a, 15b, 15c, 15d for rectifying circulating ventilation. The flow velocity of the air flowing through is uniformed. Note that the current plates 15a, 15b, 15c, 1
As 5d, for example, a punching plate in which a large number of holes are formed at a constant vertical and horizontal pitch, or one in which a large number of slits are formed can be used, and the pitch and the slits are installed more densely in the lower part than in the upper part of the straightening vane. It is preferable to use the one that can stabilize the amount of circulating air in the vertical direction and enhance the rectifying effect.

In the first and second container storage chambers 18A and 18B, as described above, a container 2 for storing a natto container 25 containing a predetermined amount of steamed soybeans inoculated with natto bacteria.
4a, 24b, 24c, and 24d are stacked and accommodated on the mount 17. In this example, each container is 99m
A natto container, which is used in a conventional method of about m square size, accommodates about 49 (7 × 7) containers. In the actual operation, the first and second container accommodating chambers 18A and 1A are used for the reason described in the first and second embodiments.
Regarding the number of containers accommodated in 8B, the average wind speed of circulating ventilation is finally 0.5 m / s to 1.0 m / s, and the average temperature difference between the inlet and outlet of the container accommodating chamber is within 3 ° C. It is preferable that the number be maintained. Specifically, when accommodating the above-mentioned containers, it is preferable to accommodate two or less container rows per container accommodation chamber.

After the required number of containers are accommodated in the first and second container accommodating chambers 18A and 18B as described above, the air conditioning units 22A and 22B and the blower fan 2 are accommodated.
Drive 3 As a result, in each of the container accommodating chambers 18A and 18B, the conditioned air adjusted to a predetermined temperature and humidity is circulated in the forward direction through the first conditioned air circulation ventilation system and the second conditioned air circulation ventilation system. And, as the reverse circulation flow, the average wind speed of circulating ventilation is 0.5 m / s to 1 m / s,
The fermentation heat generated from natto during fermentation is efficiently and uniformly absorbed by the conditioned air supplied so that the average temperature difference is within 3 ° C.

The conditioned air that has absorbed the heat of fermentation flows out from the container accommodating chambers 18A and 18B, and the air conditioning unit 22A
And after being readjusted to a predetermined temperature and humidity by 22B,
It is again supplied to the two container storage chambers 18A and 18B. As a result, the fermented natto can be efficiently fermented by the circulating ventilation of the conditioned air, and high quality and uniform quality can be fermented.

According to the above-mentioned circulation ventilation type natto fermenting chamber, the natto container accommodated in the fermenting chamber 10 is divided into two container accommodating chambers 18A and 18B and accommodated, and
The conditioned air is sent to each container accommodating chamber by the first and second independent conditioned air circulation ventilation systems. Therefore, in the case of the same production volume, the average temperature difference between the inlet and outlet of each container storage chamber of circulating ventilation is the same as that of the conventional circulating ventilation type natto fermentation chamber with only one air-conditioning circulation ventilation system. It becomes small compared to. As a result, it is possible to efficiently and efficiently produce high-quality and uniform quality natto.

Further, the container accommodating chambers and the air conditioning units are arranged so that the first and second independent air-conditioning air circulation ventilation systems are formed in one fermentation chamber 10.
Even if the production volume is doubled, for example, the equipment cost and maintenance cost can be significantly reduced compared to the case where another new fermentation chamber of the same shape and size is added as before. ,
Installation space can also be saved.

[Example 4] (The above-mentioned circulating draft natto fermentation chamber 1)
Fermentation of natto using 0) Containers containing natto containers containing steamed soybeans prepared in the same manner as in Example 1 were provided in the circulating ventilation type natto fermentation chambers shown in FIGS. 24a, 24
b, 24c, 24d). Fermentation was performed in the same manner as in Example 1 by reversing forward and backward ventilation at a temperature (40 ° C.) and humidity (90%) at an interval of 5 minutes by an ordinary method, and the average wind speed of circulating ventilation was 0.8 m. / S, fermenting was performed at an average temperature difference of circulating ventilation between the inlet and outlet of the container storage chamber of 2.5 ° C. The measurement of the average wind speed and the average temperature difference of the circulating draft was performed in the same manner as in Example 1, but in this Example,
This is carried out in both of the two container accommodating chambers, and the arithmetic mean of the average wind speed and the average temperature difference is calculated.

After fermenting for 20 hours in this manner, the natto container was taken out of the container storage chamber, placed in a low temperature aging chamber at 4 ° C., and aged for 48 hours to produce natto. The quality of the natto produced in this manner and the variation thereof were 5 to 5.5 in light of the fermentation index value described in Example 1, and it was possible to produce good quality natto with uniform quality. .

[0052]

According to the method for fermenting natto according to the present invention,
It becomes possible to manufacture high quality natto with a more uniform quality that was impossible in the past. Further, by using the circulating ventilation type natto fermentation chamber according to the present invention, it is possible to effectively produce a large amount of high-quality and uniform quality natto according to the method for fermenting natto according to the present invention.

[Brief description of drawings]

FIG. 1 is a perspective view of a circulation ventilation type fermentation chamber according to the present invention.

FIG. 2 is a vertical cross-sectional view taken along line LL of the circulation ventilation type fermentation chamber of FIG.

FIG. 3 is a horizontal sectional view taken along line HH of the circulating draft fermentation chamber of FIG.

FIG. 4 is a vertical cross-sectional view of a conventional circulating draft fermentation chamber.

[Explanation of symbols]

10 Circulating ventilation fermentation chamber 18A First container storage room 18B Second container storage chamber 14a to d Container container opening 16A First circulation ventilation room 16B Second circulation ventilation chamber 16C Third circulation ventilation room 22A First air conditioning unit 22B Second air conditioning unit 24a-d container 25 natto container

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Tsutomu Iwata             4-85, Dojoyamacho, Hekinan City, Aichi Prefecture (72) Inventor Nobuo Takashima             1-14-1 Uchikanda, Chiyoda-ku, Tokyo             Stand Plant Construction Co., Ltd. (72) Inventor Yukio Fukushima             1-14-1 Uchikanda, Chiyoda-ku, Tokyo             Stand Plant Construction Co., Ltd. (72) Inventor Yoshio Kido             1-14-1 Uchikanda, Chiyoda-ku, Tokyo             Stand Plant Construction Co., Ltd. F term (reference) 3L053 BB10                 4B020 LB14 LP18 LY04

Claims (4)

[Claims] 1. A method of fermenting natto using a circulating ventilation type natto fermenting chamber, wherein an average wind speed of circulating ventilation is 0.5 m /
The method for producing natto is characterized in that the average temperature difference between the inlet and outlet of the container storage chamber for circulating ventilation is within 3 ° C. 2. A first and second opening at both ends in the fermentation chamber.
Container accommodation chambers are arranged so as to face each other, and the first circulation ventilation chamber communicating with both the opposing opening portions of the first and second container accommodation chambers and the other opening portion of the first container accommodation chamber. A second circulation ventilation chamber that communicates with the third circulation ventilation chamber that communicates with the other open portion of the second container storage chamber is formed, and further, a first circulation ventilation chamber that communicates with one side of the first circulation ventilation chamber. And a second air-conditioning unit, the other side of the first air-conditioning unit is in communication with the second circulation air chamber, and the other side of the second air-conditioning unit is in communication with the third circulation air chamber. Includes a first container-accommodating chamber, a first circulation-ventilating chamber, a first air-conditioning unit, a second circulation-venting chamber, and a first container-accommodating chamber. Two
A second air-conditioning air circulation system, which is formed by the following container accommodation chamber-first circulation ventilation chamber-second air conditioning unit-third circulation ventilation chamber-second container accommodation chamber. In addition, the circulation ventilation type natto fermentation chamber is characterized by further comprising a control means for switching the ventilation directions of the first and second air-conditioning air circulation ventilation systems at predetermined intervals. 3. The circulating-ventilated natto fermentation chamber according to claim 2, wherein each opening of each container storage chamber is provided with a current plate. 4. The average wind speed of circulating ventilation is 0.5 m / s-1.
The circulating ventilation type natto fermentation chamber according to claim 2 or 3, characterized in that the operation is carried out at 0 m / s, and the average temperature difference between the inlet and outlet of the container storage chamber for circulating ventilation is within 3 ° C. Driving method.