JPS6053594B2 - Vinegar manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing vinegar by an aerated fermentation method.

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Although various efforts have been made to improve the construction of ``A'', there are still areas to be improved.

For example, there are methods to produce vinegar with a high acetic acid concentration using a continuous or semi-continuous fermentation method using aerated fermentation, and methods to produce vinegar at a high fermentation temperature for the purpose of reducing cooling costs. High acetic acid concentration and high temperature suppress the growth ability of acetic acid bacteria and lower the concentration of acetic acid bacteria in the moromi, resulting in a lower production rate than in the case of lower acetic acid concentration and temperature. There are many.

As mentioned above, if the growth of acetic acid bacteria is suppressed and the production rate is reduced due to high acetic acid concentration or high temperature, some means should be used to increase the concentration of acetic acid bacteria in the moromi, and eventually Naturally, attempts are made to increase production rates, typically by searching for nutritional substances that can withstand high acetic acid concentrations and high temperatures to promote growth and increase production rates. Attempts have been made to add nutrients to the moromi, or to find mutant strains and inoculate them, but although it takes a lot of effort to obtain such nutrients and mutant strains, the expected results have not been achieved. Therefore, for example, the fermentation temperature is usually below 30°C, and when fermentation is carried out at an acetic acid concentration of 7% by weight/volume or higher, productivity usually gradually decreases. Ta.

On the other hand, when carrying out the continuous fermentation method with aerated fermentation, the bacterial cells in the moromi taken out from the fermenter are separated and returned to the original fermenter for reuse. A method of increasing the production rate by increasing the amount is also known.

At that time, typical methods for separating the bacterial cells from the moromi include centrifugation and a method of allowing the moromi to stand and sedimentation, but these methods do not cause the bacterial activity to be lost due to mechanical lag. In addition, it requires a large-scale centrifugal separator and a bacterial cell sedimentation tank, and has disadvantages such as having to stand still for a long time in order to sediment the bacterial cells. In addition, the acetic acid bacteria used in the production of vinegar absolutely require oxygen, and for example, there is a special situation in which almost all of them are deactivated by interrupting ventilation for a very short period of time. It was impossible to put into practical use the method of separating the bacterial cells from the moromi and returning them to the original fermenter for reuse.

Furthermore, in order to compensate for the shortcomings of the conventional method and enable the reuse of bacterial cells, a bacterial cell separation tank with porous materials such as unglazed, sintered metal, or cellulose filters was installed inside the fermenter. A fermentation tank has been devised, but this device separates the moromi while keeping the bacterial cells in the fermentation tank, which improves the above drawbacks, but it has a complicated mechanism inside the fermentation tank. Since a bacterial cell separation tank is provided, the equipment is likely to malfunction during fermentation, and the porous material is likely to be clogged with bacterial cells and insoluble substances in the moromi, and in such cases, fermentation must be stopped. There are drawbacks such as the need to temporarily suspend operations for repairs and cleaning. On the other hand, in acetic acid fermentation, acetic acid bacteria absorb oxygen and ethanol dissolved in the moromi to perform acetic acid fermentation, and oxygen is absolutely necessary, but the ability of acetic acid bacteria to absorb dissolved oxygen is extremely strong. The oxygen dissolved in the moromi is immediately consumed by the acetic acid bacteria, resulting in a concentration of dissolved oxygen. The concentration will be very low.

Under such conditions, the production rate is proportional to the oxygen dissolution rate, so various efforts have been made to improve the oxygen dissolution rate even in vinegar production methods using aeration fermentation. For example, methods are known in which oxygen is used to aerate the air to increase the oxygen concentration in the air, or oxygen gas itself containing a trace amount of carbon dioxide is aerated. Although these methods can certainly increase the rate of oxygen dissolution into the moromi and increase the production rate, there are limits to the growth and fermentation ability of the acetic acid bacteria themselves, and the oxygen supply capacity is limited. It is almost impossible to expect to improve the growth and fermentation ability of the acetic acid bacterium itself by simply increasing the production rate, so even if it is possible to improve the production rate to a certain extent, it is impossible to improve it further. As the temperature increases, the effectiveness of using oxygen diminishes.

In particular, when fermentation is carried out at a higher fermentation temperature or acetic acid concentration as mentioned above, the fermentation ability of acetic acid bacteria is suppressed by the high fermentation temperature or acetic acid concentration itself. No matter how much you increase the supply rate, you cannot increase the production rate. The present invention overcomes the drawbacks of these conventional methods, uses an ultra-overnight device to separate acetic acid bacteria from the moromi taken out from the fermenter, and returns it to the fermenter without reducing its activity. While increasing the concentration of acetic acid bacteria in the container, in order to cope with the oxygen consumption of the high concentration of acetic acid bacteria, we use oxygen to aerate air with increased oxygen concentration, thereby increasing the production rate and efficiently producing vinegar. It is an object of the present invention to provide a method for producing vinegar by an aerated fermentation method that makes it possible to produce vinegar by a continuous fermentation method or a semi-continuous fermentation method. The moromi taken out from the fermenter is passed through an ultraviolet filtration device installed outside the fermenter, and is separated into clear moromi that does not contain acetic acid bacteria and moromi that contains acetic acid bacteria at a higher concentration than the original state. Clear moromi is discharged from the fermentation system, and moromi containing acetic acid bacteria in a higher concentration than the original state is returned to the fermenter within 1 minute after the moromi is taken out of the fermenter. A reduction process is added continuously or intermittently to the fermenter so that the moromi is reduced to a higher concentration. This is a method for producing vinegar, which is characterized in that fermentation is carried out at a dissolved oxygen concentration in the moromi of 0.2 ppm or more.

Hereinafter, the present invention will be specifically explained in detail.

First, a specific example of the apparatus used in the present invention will be explained with reference to the drawings.

In the figure, 1 is a fermenter, and a conventionally known one is used.

The fermenter 1 is provided with an aeration pipe 6 for aerating air and oxygen into the internal mash and an air introduction pipe 5 for introducing air and oxygen into the aeration pipe 6. Stirring blade 2 for finely pulverizing and dispersing and mixing in the moromi
A stirring shaft 3 is provided to connect the stirring blade 2 to an electric motor 4 provided outside the fermenter 1 in order to rotate the stirring blade 2. In acetic acid fermentation, alcohol, the main raw material, and acetic acid, the main product, are both volatile. -30%) is sufficiently mixed and can efficiently supply oxygen to the moromi. 7
is an exhaust pipe provided in the fermenter 1, from which air and oxygen separated from the moromi after supplying air and oxygen to the moromi are exhausted.

Reference numeral 8 denotes a raw material moromi input pipe provided in the fermenter 1, which is used not only to input raw material moromi into the fermenter 1 but also to input acetic acid bacteria, nutritional substances, alcohol, etc.

Reference numeral 9 denotes a mash removal pipe installed below the level of the mash in the fermenter 1. When producing vinegar by the continuous fermentation method, raw mash is continuously inputted from the mash input pipe 8 to the fermenter. When the liquid level of the moromi in the fermenter 1 rises, the moromi continuously overflows out of the fermenter 1 through the mortar removal pipe 9, so that continuous fermentation is carried out while maintaining a constant amount of moromi, that is, the liquid level. It's getting old.

Furthermore, the fermenter 1 is provided with a serpentine pipe 10 inside thereof, which allows the moromi to be cooled or heated by passing cold water or hot water through it, which is not shown in the figure. Although it is not, the temperature of the moromi is automatically measured and
The temperature of the moromi in the fermenter 1 can be kept constant by an automatic temperature controller that automatically opens and closes a solenoid valve connected to the fermenter 1. 11 is a moromi discharge pipe provided at the bottom of the fermenter 1, and is used to take out the moromi from inside the fermenter 1, and 12 and 13 are valves provided in the middle of the moromi discharge pipe 9 and the moromi discharge pipe 11. It is used by opening and closing as appropriate depending on the purpose.

Furthermore, the mash discharge pipe 11 is branched between the fermenter 1 and the valve 13, and is connected to the mash circulation pump 14 via the valve 21 and the vibrator 16, and the mash circulation pump 14 has a valve 22 in the middle. Ultrafiltration device 15 via vibrator 17 with
It is connected to the. A vibrator 18 having a valve 23 is further connected to the ultrafiltration device 15, and the tip of the vibrator 18 opens into the inside of the fermenter 1. Here, as the ultrafiltration device 15, a commonly used one can be used, but one having a filter membrane that can withstand at least an acetic acid solution of a concentration equivalent to that contained in vinegar is suitable.

The cellulose-based membrane that has been commonly used in the past is destroyed by the effects of hydrolysis and other actions due to the acetic acid in vinegar, so we recommend using a membrane that is highly resistant to acetic acid and is made of polymers such as acrylonitrile or Teflon. It is preferable to use an ultraviolet penetration device that has a The moromi taken out from the fermenter 1 is filtered through this ultrafiltration device 15, and the clear moromi that does not contain acetic acid bacteria (hereinafter referred to as clarified moromi) is passed through the clarified moromi discharge pipe 19.
is discharged from the fermentation system through the Further, the vibrator 17 is branched between the mash circulation pump 14 and the valve 22, and is connected to the mash discharge pipe 20 via the valve 24.

This mash discharge pipe 20 is used when the mash is discharged while the mash is being circulated by operating the mash circulation pump 14. Note that the valves 21, 22, 23, and 24 are opened and closed as appropriate depending on the purpose. Reference numerals 25, 26, and 27 are storage tanks for receiving the moromi containing acetic acid bacteria or the clarified mash discharged from the mash removal pipe 9, the clarified mash discharge pipe 19, and the mash discharge pipe 20, respectively.

The moromi circulation pump 14 sucks the moromi in the fermenter 1 through the mortar discharge pipe 11 and the vibrator 16, and further sends it through the vibrator 17 to the ultrafiltration device 15.
The function is to return the moromi containing acetic acid bacteria in a higher concentration than the original state (hereinafter referred to as acetic acid bacteria concentrated moromi) through the vibrator 18 into the fermenter 1, and at the same time, the ultrafiltration device 15 It also serves to apply the necessary pressure to the moromi to filter it.

Therefore, there is a device with a discharge flow rate that allows the mash in the fermenter 1 to be returned to the original fermenter 1 as acetic acid bacteria concentrated mash through the ultrafiltration device 15 within one minute. It is preferable to have a lift such that a suitable p overpressure can be applied to the ultrafiltration device 15. Note that in order to be able to circulate the moromi within one minute as described above, it is not only necessary to increase the discharge flow rate of the mortar circulation pump 14, but also to increase the flow rate of the mortar circulation system. The diameter and length of 16, 17, 18, etc. are also relevant. Therefore, the shortest distance can be made as small as possible by using the thinnest vibrator possible, which is economical. Also,
The air introduction pipe 5 branches into two parts in the middle, one of which is connected to a compressor 28 and the other to an oxygen cylinder 29.

Here, both the compressor 28 and the oxygen cylinder 29 may be conventionally known ones. Although not shown, not only one oxygen cylinder 29 but two or more oxygen cylinders 29 can be used sequentially by a switching cock. 30 and 3
1 is an air and oxygen flow meter.

32, 33 and 34 are valves, especially 32 and 34
are pressure reducing valves for reducing the pressure to an appropriate pressure when using air and oxygen gas from the compressor 28 and oxygen cylinder 29, respectively.

A dissolved oxygen meter 35 is electrically connected to a sensor 36 and is provided to measure the dissolved oxygen concentration in the moromi in the fermenter 1.

Next, the production of vinegar by continuous fermentation or semi-continuous fermentation using aerated fermentation according to the present invention using the apparatus of the above-mentioned specific example will be explained.

In the present invention, first, alcohol, water,
The mash for starting fermentation prepared using acetic acid fermentation liquid or acetic acid and nutrients for acetic acid bacteria is filled. Here, as the acetic acid fermentation liquid, a suitable moromi obtained by acetic acid fermentation, such as lees vinegar mash after completion of fermentation, is used, and as nutrients for acetic acid bacteria, for example, sake lees infusion, yeast factory scratches, sugars, inorganic salts, etc. , organic acids, etc. are used. In addition, when filling the moromi for starting fermentation, the valves 12, 1
Not only valves 3 and 21 but also valves 22, 23 and 24 are closed. After filling fermentation tank 1 with moromi for starting fermentation,
The electric motor 4 is operated to rotate the stirring blades 2 through the stirring shaft 3, and while stirring the mash, hot water or steam is passed through the cork tube 10 and heated to a predetermined temperature between 25 and 35°C.

After the temperature of the moromi reaches a predetermined temperature, a temperature controller is activated, and thereafter, the predetermined temperature is maintained at 25 to 35° C. by heating or cooling as appropriate.

Thereafter, 5 to 30% air is aerated into the mash through the air introduction pipe 5 and the aeration pipe 6 per minute based on the mash content. Air is obtained by operating the compressor 28 and controlled by the pressure reducing valve 32 to an appropriate pressure (for example, 1 to 2 k91).
After the pressure is reduced to cIt), the flow rate is adjusted to the appropriate flow rate as described above by the flow meter 30, and the air is supplied through the air introduction pipe 5 and the air diffuser pipe 6. Note that at the start of this fermentation, it is more economical to close the valve 33 and the pressure reducing valve 34 and not use oxygen gas. The air separated from the moromi is then exhausted from the exhaust pipe 7. After sufficient oxygen has been distributed to the moromi in this way, acetic acid bacteria are inoculated. In this case, it is appropriate to inoculate at least acetic acid bacteria that can ferment at the desired high acetic acid concentration and high temperature. There are no particular limitations on the inoculation method, and conventionally known inoculation means can be used. The moromi that has been inoculated with acetic acid bacteria in this way is
When aeration and stirring are performed at ~30% aeration volume and a temperature of 25 to 35°C, acetic acid bacteria proliferate and fermentation begins, and the alcohol in the moromi is converted to acetic acid, increasing the acetic acid concentration. .

When the fermentation progresses and the acetic acid concentration of the moromi has sufficiently increased, in the case of a continuous fermentation method, the raw material moromi is fed into the fermentation tank 1 from the raw material moromi input pipe 8 using a metering pump or a head, for example. Input quantitatively and continuously by means of means.

As the raw material moromi, a moromi prepared using alcohol, water, an acetic acid fermentation liquid or acetic acid, and nutrients for acetic acid bacteria is used.

The acetic acid fermentation liquid and the nutrients for the acetic acid bacteria used are the same as those described for the moromi for starting fermentation. When the raw material moromi is quantitatively and continuously put into the fermenter 1,
The amount of moromi in the fermenter 1 gradually increases, and the liquid level of the moromi becomes higher.

Therefore, the valve 12 of the moromi extraction pipe 9 is opened to allow the moromi in the fermenter 1 to overflow through the mortar extraction pipe 9, and the overflowing moromi is received in the storage tank 25. Adjust the amount of liquid in the moromi. In this way, vinegar is produced by the continuous fermentation method. In the present invention, valves 21, 22, and 23 are closed during continuous fermentation in order to forcibly increase the concentration of acetic acid bacteria in the moromi and improve the production rate. The open moromi circulation pump 14 is operated to take out the mash in the fermenter 1 from the mash discharge pipe 11, and the mash is sent to the ultra-filtration device 15 through the vibrators 16 and 17, where the mash is filtered to produce clear mash and acetic acid bacteria concentration. An operation is added in which the moromi and moromi are separated and the acetic acid bacteria concentrated moromi is returned to the original fermentation tank 1.

In addition, the clarified moromi is passed from the ultrafiltration device 15 to the clarified moromi discharge pipe 19.
It is discharged to the storage tank 26 through.

The opening degree of the valves 21, 22, and 23 is adjusted to adjust the circulation speed of the mash and the filtration pressure applied to the filtration membrane of the ultrafiltration device 15. The circulation speed of the moromi is that after the moromi is taken out from the fermenter 1, it passes through the circulation pump 14 and the ultrafiltration device 15, becomes acetic acid bacteria concentrated moromi, and then returns to the original fermenter 1.
Adjust so that the time it takes to return to the inside is within 1 minute. Further, the overpressure is normally adjusted to be maintained at about 1 to 2k91cT1. In this way, the ultrafiltration device 15 filters the moromi and takes out the clarified moromi, but if the extraction flow rate, that is, the overspeed, is greater than the rate at which raw material moromi is introduced into the fermenter 1, the fermenter The amount of moromi in 1 gradually decreases until it is almost empty and becomes empty.

Therefore, the overspeed of the ultrafiltration device 15 is set to be less than the input speed of the raw material mash, and the portion of the mash that is not discharged at an insufficient speed and the liquid level of the mash is to be raised is discharged from the fermentation pipe 9. The liquid level of the moromi is kept constant by overflowing to the outside of tank 1. In addition, if the filtration speed is unavoidably higher than the feeding speed of the raw material, the ultra-low filtration device 15 is used to keep the liquid level of the moromi almost constant.
Perform filtration intermittently. That is, when the clarified moromi is extracted by filtering the moromi using the ultrafiltration device 15,
Since the input speed of the raw mash is slower, the mash in the fermenter 1 gradually decreases, but when the mash reaches its limit, the overflow is stopped and the raw mash is added again to restore the original mash. When the mash volume recovers, filtration is performed again, and when the mash volume decreases too much, filtration is stopped again, thereby ensuring a nearly constant mash volume, or liquid level. Keeping the above points in mind, by continuing to filter the moromi using the ultrafiltration device 15 to obtain acetic acid bacteria-concentrated moromi and return it to the fermenter 1, the concentration of acetic acid bacteria in the moromi in the fermenter 1 can be increased. gradually increases, and finally reaches a concentration of acetic acid bacteria that corresponds to the highest oxygen supply capacity available in the fermenter used.

In such a state, even if the acetic acid bacteria concentration is increased any further, the acetic acid bacteria will be in a state of insufficient oxygen, and the production rate will therefore no longer be improved. In such a state, the oxygen consumption ability of acetic acid bacteria is greater than the rate of oxygen dissolution into the mortar, and the dissolved oxygen is immediately consumed by acetic acid bacteria, so at this point, the dissolved oxygen meter 35
When the sensor 36 is activated and the dissolved oxygen concentration in the fermenter 1 is measured, it is found that it is almost zero.

In the present invention, oxygen is added from the oxygen cylinder 29 before the dissolved oxygen in the moromi approaches zero, which may reduce the activity of acetic acid bacteria, and preferably before it reaches 0.2 ppm or less. By starting the supply of gas and aerating air with increased oxygen concentration, the rate of oxygen dissolution into the moromi is increased.

In this way, by fully matching the oxygen consumption rate of acetic acid bacteria that has been improved by using the ultrafiltration device, it is possible to achieve a very high production rate that could not be achieved conventionally. It is.

To supply oxygen gas, first, the pressure is reduced to an appropriate pressure (for example, 1 to 2 kgIc71f) using the pressure reducing valve 34, and then the valve 33 is opened and the flow rate is adjusted to an appropriate flow rate using the flow meter 31 for ventilation. However, in this case, the air from the compressor 28 is also vented at the same time, and the oxygen gas from the oxygen cylinder 29 is mixed with air in the middle of the air introduction pipe 5 and vented to the aeration pipe 6.

The flow rate of air and oxygen gas and their mixing ratio are changed according to the oxygen consumption rate of the acetic acid bacteria in the moromi in the fermenter 1, and the mortar is filtered by an ultrafiltration device 15 to obtain acetic acid bacteria concentrated moromi. If the reduction into the fermenter 1 is continued, the concentration of acetic acid bacteria in the moromi in the fermenter 1 will further increase.
The oxygen consumption rate increases accordingly, and the dissolved oxygen concentration, which had once been high, begins to decrease. While measuring the concentration of dissolved oxygen in the mash using the oxygen meter 35, the flow rate of oxygen gas is increased to increase the mixing ratio with air to increase the rate of oxygen dissolution into the mash.

Note that if it is necessary to further improve the oxygen dissolution rate, the air from the compressor 28 is transferred to the valve 3.
2 may be closed and not used at all, and only oxygen gas from the oxygen cylinder 29 is vented. Even in such a case, the dissolved oxygen concentration in the moromi in the fermenter 1 must be maintained at 0.2 ppm or more. is the same as above.

In any case, the production rate is determined by the degree of concentration of acetic acid bacteria in the fermenter 1 by the ultrapolar filtration device 15, the flow rate of oxygen gas and air, and the mixing ratio. Once a certain high production rate has been achieved,
If continuous fermentation is possible without reusing acetic acid bacteria by ultrafiltration at the desired high acetic acid concentration or high temperature, in other words, if there is even a small amount of fermentation or proliferation, such a method is recommended. If a state is reached where the production rate does not improve even with the addition of filtration using an ultrafiltration device, the ultrap-filtration is temporarily interrupted and normal continuous fermentation is continued, and once the production rate has decreased to a certain extent, the production rate is increased again. It is desirable to perform ultrafiltration intermittently by restarting ultrafiltration, then interrupting and restarting ultrafiltration, in order to maintain almost the maximum productivity. Even in this case, aeration of air with increased oxygen content will reduce the dissolved oxygen concentration in the moromi to 0.2pp.
It continues while being adjusted to maintain m or more.

In addition, if fermentation is carried out at the desired high acetic acid concentration or high temperature but does not grow, the acetic acid bacteria may be grown at a lower acetic acid concentration or temperature, and the acetic acid bacteria may be concentrated and the oxygen content reduced by ultrafiltration. After the acetic acid bacteria concentration is sufficiently increased by aeration of air with increased acetic acid concentration, the desired high acetic acid concentration and high temperature are achieved. At this time, the valve 12 of the mortar removal pipe 9 is closed and the ultraviolet filtration device 15 is turned on. The amount of moromi corresponding to the input amount of raw material moromi is taken out from the clarified moromi discharge pipe 19 as clarified moromi, and the acetic acid bacteria are completely removed from the fermentation system. Fermentation is continued while maintaining high productivity. This method is also possible, and in this case as well, air with an increased oxygen content is aerated so as to maintain a dissolved oxygen concentration of 0.2 ppm or more, as described above.

The moromi in the storage tank 25 obtained as described above is subjected to p-filtration and sterilized to produce a vinegar product, and the clarified moromi in the storage tank 26 is sterilized if necessary to produce a vinegar product. Vinegar is produced by the continuous fermentation method through aerated fermentation using an ultrapolar filtration device in the manner described above, but in the case of the semi-continuous fermentation method, the operations are almost the same as the continuous fermentation method.

In the case of semi-continuous fermentation using aerated fermentation, the fermentation tank 1 is filled with moromi to start fermentation, stirred and heated to a predetermined temperature, then aeration is started, and acetic acid bacteria are inoculated to start fermentation. However, when the fermentation progresses and the acetic acid concentration rises to the target concentration, usually about half of the mash is taken out from the mash discharge pipe 11 of the fermenter 1 without interrupting aeration and stirring, and approximately the same amount of raw mash is extracted. is introduced from the raw material moromi injection pipe 8.

Therefore, the acetic acid concentration of the moromi in the fermenter 1 is low at the start of fermentation, gradually increases as fermentation progresses, and reaches its maximum when the moromi is taken out.

Immediately after the fermentation tank 1 is filled with the raw material moromi after the moromi is taken out, the temperature is at its lowest level, and as the fermentation progresses, it rises again until it reaches the highest level when the moromi is taken out, and a cycle continues.

During this time, the acetic acid bacteria begin to proliferate from a state where the acetic acid concentration is low, and simultaneously perform fermentation to increase the acetic acid concentration while continuing to proliferate. Additionally, the alcohol concentration in the moromi is generally highest immediately after filling the raw moromi, and decreases as fermentation progresses as alcohol is converted to acetic acid, reaching its lowest level when the moromi is taken out. In the case of a semi-continuous fermentation method in which fermentation continues in this manner, the ultrafiltration device 15 is used to filter the moromi. It is preferable to carry out filtration at the time of taking out the moromi.

Otherwise, the mash that has not reached the desired acetic acid concentration and has a high alcohol concentration will be clarified and discharged from the ultraviolet filtration device 15. This is because the concentration and alcohol concentration are both inappropriate and undesirable for use as a vinegar product. Note that the process of filtering the mash using the ultrafiltration device 15 and discharging the clear mash to the storage tank 26, and returning the acetic acid bacteria concentrated mash to the fermentation tank 1 to reuse the acetic acid bacteria is semi-continuous fermentation. The same applies to the continuous fermentation method described above.

However, when producing vinegar using a semi-continuous fermentation method, it is preferable that the alcohol concentration of the moromi to be taken out is as low as possible and the acetic acid concentration is high. % by volume), not only growth but also hardly any fermentation takes place, so it is desirable to take out the moromi in the fermenter 1 in as short a time as possible.

In this case, it is preferable to use an ultrafiltration device with a suitably large overrate; however, the installed ultrafiltration device is capable of discharging a predetermined amount of mash from the fermenter 1 within a predetermined period of time. There will be cases where this is not the case. In such a case, valve 24
The amount of moromi that cannot be filtered within the time allowed for opening and removing the moromi is discharged to the storage tank 27 through the mortar discharge pipe 20. In this way, the acetic acid bacteria that would normally be discharged out of the fermenter 1 together with the moromi when the moromi is taken out are separated from the mortar using the ultrafiltration device 15 and returned to the fermenter 1 in the form of acetic acid bacteria concentrated moromi. By reusing the ultraviolet filtration device 15, the concentration of acetic acid bacteria in the moromi in the fermenter 1 can be increased compared to when the ultraviolet filtration device 15 is not used. It becomes possible to carry out semi-continuous fermentation at a high production rate by supplementing the growth activity and fermentation ability of .

Note that the higher the concentration of acetic acid bacteria in the moromi in the fermenter 1 using the ultrapolar filtration device 15, the higher the production rate, but in both the semi-continuous fermentation method and the continuous fermentation method Similarly, there is a limit to improving the production rate depending on the maximum oxygen supply capacity that can be obtained with the fermentation equipment used, and when the concentration of acetic acid bacteria is reached to the extent that the maximum production rate can be obtained,
When we measure the dissolved oxygen concentration in the moromi, we find that it is almost zero. Therefore, as in the case of the continuous fermentation method described above, supply of oxygen gas from the oxygen cylinder 29 is preferably started before the dissolved oxygen concentration becomes 0.2 ppm or less, and air with increased oxygen concentration is aerated.

Then, the flow rate of air and oxygen gas and their mixing ratio are changed according to the oxygen consumption rate by the acetic acid bacteria in the moromi, and the dissolved oxygen meter 35 is adjusted so as to maintain the dissolved oxygen concentration in the moromi at 0.2 ppm or more. Therefore, while measuring the dissolved oxygen concentration in the moromi, it is possible to increase the flow rate of oxygen gas and increase the mixing ratio with air to increase the rate of oxygen dissolution into the moromi, and the method of supplying oxygen gas can also be done in the same manner as described above. It is similar to the fermentation method Yanghe. The production rate is determined by the degree of concentration of acetic acid bacteria in the fermentation tank 1 by the ultrafiltration device 15, the flow rate and mixing ratio of oxygen gas and air, and the production rate is determined at a certain target production rate. Once this has been achieved, it is sufficient to add ultra-filtration to the extent that the production rate or acetic acid bacteria concentration can be maintained. Once the limit has been reached, ultra-deep filtration will be stopped in the next cycle, and if it is recognized that the production capacity has begun to decline, ultra-deep filtration will be carried out again in that cycle as appropriate. Almost maximum productivity can be maintained by carrying out ultrafiltration, and in this case as well, continuous aeration of air with increased oxygen content is necessary to maintain a dissolved oxygen concentration of 0.2 ppm or more. The same is true for the fermentation method.

The moromi in the storage tank 27 obtained as described above is filtered and sterilized to produce a vinegar product, and the clarified moromi in the storage tank 26 is sterilized if necessary to produce a vinegar product.

In this way, when producing vinegar using the continuous or semi-continuous fermentation method using aerated fermentation, the moromi is filtered using an ultra-filtering device, and the resulting acetic acid bacteria concentrated moromi is returned to the original fermentation tank. While increasing the concentration of acetic acid bacteria in the moromi through reduction, the concentration of dissolved oxygen in the moromi in the fermenter is maintained at 0.2 ppm or higher by aerating air with increased oxygen content. It is possible to increase production capacity, which has been suppressed by acetic acid concentration and high temperature, but in doing so, the growth activity and fermentation ability of the acetic acid bacteria that are returned to the original fermenter have been deactivated. is meaningless.

Therefore, since acetic acid bacteria in particular are sensitive to oxygen deficiency due to their characteristics, the present inventors efficiently reused acetic acid bacteria using an ultraviolet filtration device with little impact on the acetic acid bacteria. In order to do this, what kind of circulation speed should be used for the moromi? In other words, the moromi taken out from the fermenter 1 passes through the mortar circulation pump 14 and the ultra-filtering device 15, becomes an acetic acid bacteria-concentrated mortar, and is recycled again. The following experiment was conducted in order to determine how much time should be taken for the fermentation tank 1 to be reduced.

That is, an 80' capacity fermenter 1, a maximum lift of 20 m, a maximum discharge flow rate of 20'/min, a mash circulation pump 14, and a filtration surface/area of 0.
．． Ultrafiltration device 15 with a maximum p overrate of 10'/hour (vinegar) at 2rr1 and a molecular weight cut-off of approximately 13,000, a compressor 28 with a maximum working pressure of 10k91cIi and an air supply capacity of 75e per minute, and a 7-point compressor with a maximum working pressure of 10k91cIi and 75e per minute. Using a fermentation device as shown in the drawing, which consists of an oxygen cylinder 29 containing pure oxygen, etc., the fermentation tank 1 contains sake lees infusion, alcohol, acetic acid fermentation liquid, and water, each having an acetic acid concentration and an alcohol concentration of 1 weight. /volume% and 5% by volume of fermentation starting fermentation fermentation fermentation paste 45e is introduced from the raw material moromi input pipe 8, and the electric motor 4 is operated to rotate the stirring blade 2 attached to the tip of the stirring shaft 3 at approximately 700 revolutions/minute. The moromi was heated to 32'C by passing warm water at 60'C into the cork tube 10 while stirring the moromi by rotating at a rotational speed of .

When the temperature of the moromi reaches 32, the temperature of the moromi is set to 32.
The temperature was maintained between ~32.5°C. and compressor 2
8 was activated to open the pressure reducing valve 32, and air was aerated through the air introduction pipe 5 and the aeration pipe 6 to the fermentation starting moromi in the fermentation tank 1. Note that the air was adjusted to a pressure of 1k91d using a pressure reducing valve 32 and a flow rate of 5e per minute using a flowmeter 30 for ventilation. After sufficient oxygen was supplied to the moromi, acetic acid bacteria were inoculated to start fermentation.

In this case, the inoculation is carried out by inoculating approximately 5e of moromi, which is continuously fermented at 30°C in a 25 kt aerated fermenter with an acetic acid concentration of 5 to 5.5% by weight/volume, into fermenter 1 within one minute. This was done by moving. After that, when the acetic acid bacteria proliferate and fermentation progresses, and the acetic acid concentration in the moromi reaches 5% by weight/volume, it is composed of sake lees infusion, alcohol, acetic acid fermentation liquid, and water, and the acetic acid concentration and alcohol concentration are each 1% by weight/volume. Quantitatively and continuously injecting the raw material moromi prepared to 5% by volume from the raw material mortar input pipe 8 according to production capacity so as to maintain the acetic acid concentration of the moromi at 5 to 5.5% by weight/volume, and The valve 12 of the mortar removal pipe 9 was opened to cause the mortar to overflow into the storage tank 25.

After stably fermenting for about one week at a fermentation temperature of 32 to 32.5°C, the valves 21, 22, and 23 are opened and the mash circulation pump 14 is activated to transfer the mash in the fermenter 1 to the fermenter 1. −
Circulate in the order of vibrator 16 → moromi circulation pump 14 → vibrator 17 → ultrafiltration device 15 → vibrator 18 → fermentation tank 1, and at the same time adjust the opening degree of valves 21, 22, and 23 with ultrafiltration device 15. The fermentation process has begun.

Then, by adjusting the opening degree of the valves 21, 22, and 23, the moromi is taken out from the fermenter 1, and the moromi circulation pump 14 and the limiter are removed. The amount of time it took for the acetic acid bacteria to pass through the filtration device 15, become a concentrated mash of acetic acid bacteria, and return to the original fermenter 1 was varied to see how the production capacity varied.

The results are shown in Table 1. From the results in Table 1, 2.3y if the ultrafiltration device is not activated.
The production rate was 3.3 y/l/hour by operating the ultrapolar filtration device and increasing the concentration of acetic acid bacteria in the moromi in the fermenter 1. It can be seen that the production speed can be increased up to a very high time.

Since the production rate of 3.3 y/f/hour is the highest, it can be inferred that the oxygen supply capacity of this fermentation apparatus is the limiting factor in this case. It was also found that if the time required for circulation of the moromi is longer than 1 minute, even if the ultrafiltration device is activated to increase the concentration of acetic acid bacteria in the moromi, the production rate will actually decrease. It can be seen that when operating the filtration device to increase the concentration of acetic acid bacteria in the moromi in the fermenter 1, it is preferable to keep the circulation speed of the moromi within 1 minute.

Next, acetic acid bacteria are separated from the moromi taken out from the fermenter using an ultrafiltration device and returned to the fermenter without reducing activity, increasing the concentration of acetic acid bacteria in the moromi in the fermenter.
In order to cope with the high concentration of oxygen consumed by acetic acid bacteria, we carried out the following experiments and experiments to clarify that the production rate can be improved by aerating air with increased oxygen concentration using oxygen. The results are shown below.

That is, using the fermentation apparatus shown in the drawings in the same way as in the previous experiment, about 45 e of fermentation starting material was introduced into the fermentation tank 1 through the raw material input pipe 8, and the electric motor 4 was operated to turn the stirring shaft 3 on. The stirring blade 2 attached to the tip was rotated at about 700 revolutions per minute to stir the mash, and hot water at 60°C was passed through the cork tube 10 to warm the mash to 30'C.

When the temperature of the moromi reaches 30℃, the temperature of the moromi should be increased to 30℃.
maintained at between 0 and 30.5°C, and heated to 1k in the same manner as above.
Aeration was started at a pressure of gIcIt at an aeration rate of 5' per minute, and when sufficient oxygen was supplied to the mash, acetic acid bacteria were inoculated to start fermentation.

In this case, the inoculation is carried out in a 25k1 aerated fermenter at 30'C with an acetic acid concentration of 5 to 5.5 wt/vol%, and approximately 5f of the mash is transferred to fermenter 1 within 158 mL. This was carried out by After inoculation, when the acetic acid bacteria proliferate and fermentation progresses until the acetic acid concentration in the moromi reaches 5% by weight/volume, the same raw material moromi as described above is poured into the raw material moromi from the raw material moromi input tube 8 so that the acetic acid concentration in the moromi is 5 to 5%. Quantitatively and continuously inputting the mortar according to production capacity to maintain 5% by weight/volume, and removing the mash from the pipe 9
The valve 12 was opened to allow the moromi to overflow into the storage tank 25.

After carrying out stable fermentation for about one week at 30 to 30.5°C in this way, valves 21, 22 and 23 are opened,
The moromi circulation pump 14 is operated to circulate the moromi in the fermenter 1 in the same manner as described above, and at the same time the valves 21, 22 and 23 are activated.
The ultrafiltration device 15 started filtering the moromi while adjusting the degree of opening.

In this case, the circulation time of the moromi was set to about 1 mark 2.
Continuous fermentation was thus continued while carrying out ultrafiltration and adjusting the input rate of raw material moromi according to production capacity so as to maintain the acetic acid concentration in the moromi at 5 to 5.5% by weight/volume.
When stable production became possible, the dissolved oxygen meter 35 and sensor 36 were activated to measure the dissolved oxygen concentration in the mash in the fermenter 1, and it was found that it was almost at zero.

Therefore, while continuing the filtration of the mash by the ultraviolet filtration device 15, the valve 33 and the pressure reducing valve 34 were opened to reduce the pressure to 1k91c1.
1, and while adjusting the flow rate with the flow meter 31, ventilation of air with increased oxygen content by supplying oxygen gas was started. Then, while aerating air with increased oxygen content by supplying oxygen gas, the dissolved oxygen meter 35 and sensor 3
6 to measure the dissolved oxygen concentration in the moromi in the fermenter 1,
The flow rate of oxygen gas was gradually increased so that the value was maintained at 0.2 ppm or more. In this way, we finally decided to supply oxygen gas at a rate of about 2 f/min and waited for the production rate to stabilize. The dissolved oxygen concentration in the moromi began to gradually decrease, and when it became difficult to maintain the concentration above 0.2 ppm, the ultrafiltration of the moromi using the ultrafiltration device 15 was interrupted, and the dissolved oxygen concentration was again reduced. When the concentration started to rise, the limit offshore flow was started, thereby maintaining almost stable production. The results of the above experiments are shown in Table 2. From the results in Table 2, the production rate can be improved by adding ultrafiltration, but in addition, oxygen gas is used to aerate air with a higher oxygen concentration than normal, reducing the dissolved oxygen concentration in the moromi to 0. It can be seen that if the concentration is maintained at 2 ppm or more during fermentation, the production rate can be dramatically improved.

As described above, according to the present invention, when producing vinegar by a continuous fermentation method or a semi-continuous fermentation method by aerated fermentation, acetic acid bacteria are separated and activated from the moromi taken out from a fermenter using an ultraviolet filtration device. While increasing the concentration of acetic acid bacteria in the moromi in the fermenter without reducing the concentration of acetic acid bacteria, we used oxygen to increase the oxygen concentration in order to cope with the increased oxygen consumption of the acetic acid bacteria. The present invention is an extremely advantageous method for producing vinegar by aerated fermentation, since the production rate can be increased to an extent that was previously unimaginable by aerating air.

Next, examples of the present invention will be shown.

Example 1 80e capacity fermenter 1, maximum lifting height 20m. and an ultrafiltration device 15 with a maximum discharge flow rate of 20 e/min, a filtration area of 0.2 d, a maximum overspeed of 10'/hour (vinegar), and a molecular weight cut-off of approximately 13,000, maximum usage. pressure is 10k
Sake lees infusion, alcohol, Approximately 45e of moromi for starting fermentation, consisting of acetic acid fermentation liquid and water, with acetic acid concentration and alcohol concentration of 2% by weight/volume and 6% by volume, respectively.
is charged through the raw material mash injection pipe 8, and the electric motor 4 is operated to move the stirring blade 2 attached to the tip of the stirring shaft 3 to about 70 m
The moromi was stirred by rotating at a rotational speed of 0 revolutions/minute.

At this point, not only valve 13 but also valves 12, 21, 2
2, 23 and 24 were also closed. Also valves 32, 3
3 and 34 were also closed. After that, about 6 to 10
The moromi was heated to about 33°C by passing warm water at 0°C, and then a temperature controller was operated to maintain the temperature at 33 to 33.5°C.

Then, the compressor 28 was activated, the pressure reducing valve 32 was opened, and air was aerated through the air introduction pipe 5 and the aeration pipe 6 into the fermentation-starting mash in the fermenter 1. In addition, the air is 1k91c due to the pressure reducing valve 32! Ventilation was carried out at a pressure of 5e per minute and a flow rate of 5e per minute using a flowmeter 30. In this way, air at a temperature of 33 to 33.5°C and a pressure of 1 k91 cI is aerated at an air flow rate of 51 per minute and stirred at a rotational speed of about 700 revolutions per minute, and the fermentation tank 1 is sufficiently filled with air. Once the oxygen is flowing, the acetic acid concentration is 5 to 5.5 in another fermenter.
Approximately 5e of the mash containing acetic acid bacteria, which is undergoing continuous fermentation at a temperature of 30 to 30.5°C in weight/volume%, is transferred through the raw material mash input pipe 8 in about a ratio of seconds, and the total amount of mash is approximately 50e. The vaccination was completed.

The acetic acid concentration in the moromi immediately after inoculation is 2. The alcohol concentration is 5. The melt amount was %, but after inoculation it was 23%.
At the hour, the acetic acid concentration in the moromi was 2.8% by weight/volume.
It was observed that fermentation had started.

Furthermore, 7S after vaccination! In the middle, the acetic acid concentration in the moromi is 6.7% by weight/volume, and the alcohol concentration is 0. The melt amount was %. Therefore, it consists of sake lees infusion, alcohol, acetic acid fermentation liquid, and water, and the acetic acid concentration and alcohol concentration are each 1% by weight/volume.
and 7% by volume of the raw material moromi is continuously introduced through the raw material moromi input pipe 8 using a metering pump until the acetic acid concentration of the moromi is 7 to 7.5.
Dosing speed was adjusted to maintain weight/volume %.

At the same time as starting to add raw material moromi, the valve 12 of the moromi take-out pipe 9 was opened to cause the moromi in the fermenter 1 to overflow into the storage tank 25 outside, but at that time, the height of the moromi take-out pipe 9 was adjusted The liquid volume of the moromi in the fermenter 1 was always maintained at about 50e. In this way, the acetic acid concentration of the moromi is 7-7.5% by weight/volume and the alcohol concentration is 0.3-0. Fermentation was continued while adjusting the input rate of the raw material moromi to maintain the stoichiometry %, and the production rate stabilized at 1.5y acetic acid/e moromi/hour. Therefore, about 7 days after the start of fermentation, the valves 21, 22, and 23 are opened, the moromi circulation pump 14 is activated, and the vibrator 16,
While circulating the moromi through 17 and 18, the valve 2
1, 22, and 23 so that the circulation time of the moromi is about w seconds and the overpressure of the ultrafiltration device 15 is 1.0 k9 nod on average. I started overdoing it.

In this way, the moromi is circulated by the moromi circulation pump 14 and passed through the ultrafiltration device 15 to separate it into clear moromi and acetic acid bacteria-enriched moromi, and the acetic acid bacteria-enriched moromi is the original fermented moromi. When fermentation was continued while being returned to tank 1, the concentration of acetic acid bacteria in the moromi gradually increased, and at the same time, the production rate began to increase, so the input rate of raw material moromi was increased according to the production rate. The acetic acid concentration of the moromi is 7-7.5% by weight/volume and the alcohol concentration is 0.3-0. Further fermentation was continued while adjusting to maintain the % loading. Approximately 6 days after starting concentration of acetic acid bacteria using the ultrafiltration device 15, the production rate reached approximately 3.5 days.
The ratio was 1y acetic acid/'moromi/hour.

At this point, the dissolved oxygen meter 35 and sensor 36 were activated to measure the dissolved oxygen concentration in the fermenter 1, and it was found to be 0.2~
It was approximately 0.5 ppm, and it was judged that it would be impossible to further increase the production speed if the situation remained as it was. Therefore, while continuing to pass the moromi using the limit passing device 15, the valve 33
and open the pressure reducing valve 34 to reduce the pressure of oxygen gas to 1k91
Supply of oxygen gas was started as cIL, and the flow rate of oxygen gas at this point was 0.5 e/min.

Then, the dissolved oxygen meter 35 and sensor 36 are activated,
While measuring the dissolved oxygen concentration in the fermentation tank 1, the concentration of dissolved oxygen in the fermentation tank 1 is controlled by the ultrafiltration device 15 to maintain the dissolved oxygen concentration in the range of approximately 0.2 to 2 ppm. The flow rate of oxygen gas was gradually increased depending on the degree of concentration of acetic acid bacteria in the moromi. In addition, when supplying oxygen gas,
This was done in such a way that the supply of the next oxygen gas was not interrupted before the oxygen gas in one oxygen cylinder was completely consumed. About 5 days after starting the supply of oxygen gas, the production rate obtained in fermenter 1 reached about 6.3 g acetic acid/e moromi/hour,
At this time, the supply rate of oxygen gas was about 12'/min.

Then, the oxygen gas supply was set to about 2e/min, and the dissolved oxygen meter 3
5 and the sensor 36 to measure the dissolved oxygen concentration in the moromi in the fermenter 1, and check that the value is approximately 0.2 to 2p.
In order to maintain the concentration of acetic acid bacteria in the mash in the fermenter 1 through filtration in the ultrafiltration device 15, the consumption of oxygen increases, and the dissolved oxygen concentration in the mash increases. is 0.7! When it became difficult to maintain the mash at Ppm or higher, the process of passing the mash through the ultrafiltration device 15 was temporarily interrupted. After a while, the production rate slowed down a little and the dissolved oxygen concentration in the mash in the fermenter 1 rose, and when it was about to reach 2 ppm or more, ultrafiltration was performed again.
When the production rate is 3y acetic acid/e moromi/hour and the dissolved oxygen concentration in the moromi in the fermenter 1 is about to drop to 0.2 ppm or less, the ultrafiltration device 15 filters out the moromi. When the filtration is stopped and the production rate further decreases and the dissolved oxygen concentration in the mash in the fermenter 1 begins to rise, the ultrapolar filtration is restarted and the air with increased oxygen content is replaced with oxygen gas. Continuous fermentation was carried out for about 3 weeks at a very high production rate of an average of 6y acetic acid/'moromi/hour, while maintaining the dissolved oxygen concentration in the moromi in the fermenter 1 within the range of approximately 0.2 to 2 ppm while providing ventilation. continued. The moromi in the storage tank 25 obtained as described above is sterilized by P filtration to produce a vinegar product, and the clarified moromi in the storage tank 26 is sterilized if necessary to produce a vinegar product.

Example 2 Using a fermentation apparatus as shown in the drawing similar to that described in Example 1, a fermentation tank 1 containing sake lees infusion, alcohol, acetic acid fermentation liquid, and water with an acetic acid concentration and an alcohol concentration of 6.5 weight each. /volume% and 2. Approximately 45 e of mortar for starting fermentation is filled through the raw material mortar input pipe 8, and the electric motor 4
The stirring blade 2 attached to the tip of the stirring shaft 3
was rotated at a rotational speed of about 700 revolutions/minute to stir the moromi.

At this point, valves 12, 13, 21, 22, 23, 2
4, 32, 33 and 34 were closed. and snake pipe 1
Heat the moromi to about 30'C by pouring hot water at about 60°C into the oven, and then operate the temperature controller to keep the temperature of the moromi at 29.5~29.5°C.
It was maintained at 30.5°C. After that, compressor 2
8 was activated to open the pressure reducing valve 32, and air was aerated through the air introduction pipe 5 and the aeration pipe 6 into the mash in the fermentation tank 1 for the start of fermentation. In addition, the air is 1k91c due to the pressure reducing valve 32!
Ventilation was carried out at a pressure of 5e per minute and a flow rate of 5e per minute using a flowmeter 30. In this way, the temperature is 29.5 ~
While aerating air at a temperature of 30.5°C and a pressure of 1k91cI1 at an aeration rate of 5' per minute and stirring at a rotational speed of about 700 revolutions per minute, when sufficient oxygen has spread to the moromi in the fermenter 1, the inoculation is carried out. I did this.

In other words, about 5e of moromi containing acetic acid bacteria with an acetic acid concentration of about 7.5% by weight/volume is transferred from another fermentation tank in which fermentation is carried out by a semi-continuous fermentation method to the raw material moromi injecting tube within about 10 seconds. The inoculation was completed by transferring to the fermenter 1 through 8 to make the total mash to be about 50'. The acetic acid concentration in the moromi immediately after inoculation is 6. Weight/
Alcohol concentration in volume % is 2. However, at 17 Vff after inoculation, the acetic acid concentration was 7. The alcohol concentration was 1.2% by volume (volume/volume%). Therefore, an alcohol solution with an alcohol concentration of about 5% by volume is poured at a rate of about 200ml per hour.
Fermentation was continued by continuously adding raw materials through the moromi input tube 8 at a rate of 1, but the acetic acid concentration was 14.1% by weight/volume.
At this time, the addition of a total of 10.5 e of alcohol solution was completed, and the alcohol concentration of the moromi was 1.7% by volume. Further fermentation is continued until the acetic acid concentration reaches 15. Weight/
When the volume reaches %, the valves 21 and 24 are opened, and the moromi circulation pump 14 is operated at the same time, so that the moromi in the fermenter 1 reaches approximately 20%.
The moromi was taken out to the storage tank 27 through the vibrators 16, 17, and 20 so that

The removal of the moromi is completed in 3 steps by adjusting the opening degree of the valves 21 and 24, and after the removal is completed,
Immediately made from sake lees infusion, alcohol, acetic acid fermentation liquid, and water, with acetic acid concentration and alcohol concentration of 0.5% by weight/volume.
Approximately 30 e of raw material mash of 3% by volume was charged into the fermenter 1 at a rate of approximately 5' per hour. After the removal of the moromi was completed, the mortar circulation pump 14 was of course stopped, and the valves 21 and 24 were also closed. It took about 6 hours to finish filling the raw material moromi, and the acetic acid concentration in the moromi immediately after filling was approximately 6.7% by weight/volume, and the alcohol concentration was 1. The melt amount was %. Approximately 5 hours after filling the raw material moromi, the acetic acid concentration in the moromi was 7.2% by weight/volume and the alcohol concentration was 0.9% by volume. Fermentation was further continued by adding at a rate similar to the above.

Approximately 4 minutes after starting addition of the alcohol solution, the acetic acid concentration in the moromi was 14.1% by weight/volume, and the alcohol concentration was 1.5%. Weight %, i.e. total concentration [acetic acid concentration (weight/volume %)
)+alcohol concentration (volume %)] was 15.7%, so the addition of the alcohol solution was stopped at this point, and the fermentation was continued. After another 5 hours, the acetic acid concentration was 15
．． Since the alcohol concentration was 0.4% by volume at 3% by weight/volume, 2% of the moromi was added to the fermenter 1 in the same manner as above.
Leave 0e and take out the rest, and add 30e of the same raw material moromi as above.
After filling, fermentation was carried out in the same manner as above.

In this way, when the acetic acid concentration reached 15% by weight/volume or more, all of the moromi in the fermenter 1 was removed, leaving only 201.
When we repeated 5 cycles of semi-continuous fermentation by adding 30e of new raw material moromi and further adding alcohol solution, the average production rate was about 1.4y/y, not considering the first cycle at the start of fermentation. e/time has come.

Therefore, from the 6th cycle onward, when the acetic acid concentration in the moromi reaches 15% by weight/volume or higher and it is time to take out the moromi, the valves 22 and 23 are opened in addition to the valves 21 and 24, and the mortar circulation pump 14 is activated. The moromi was taken out to the storage tank 27 through the vibrators 16, 17 and 20, and could be returned to the ultrafiltration device 15 and the fermenter 1.

Then, by adjusting the opening degree of these valves 21, 22, 23 and 24, the p overpressure in the ultrafiltration device 15 is on average about 1.5 kg 1 cT1, the filtration rate is 15'/hour, and the amount of water taken out from the fermenter 1 is adjusted. The circulation speed was such that the fermented moromi could be returned to the fermenter 1 as an acetic acid bacteria-concentrated moromi within 2 hours. In this way, for about an hour, while ultrafiltering the moromi, 15' of clear moromi was obtained from Vibe 19, and then again from Vibe 2.
Approximately 25' of the moromi that could not be filtered was taken out from 0, and the acetic acid bacteria concentrated moromi was returned to the fermenter 1 to make the amount of moromi in the fermenter 1 20e, and then the ultrafiltration was stopped and immediately the The same raw material moromi was prepared in the same manner as above until the total amount of moromi in the fermenter 1 was about 5.
It was filled so that it was 0'.

After filling the raw material moromi, the acetic acid concentration of the moromi in the fermenter 1 was 7.0% by weight/volume, and the alcohol concentration was 13% by volume, but after 4 hours, the acetic acid concentration was 7.5% by weight/volume. %, and the alcohol concentration is 0. When the melt amount reached %, addition of the alcohol solution was started at a rate of about 300 ml/hour. Then, the fermentation was further continued, and when the addition of 10.5' alcohol solution was completed 3 hours after the start of addition of alcohol solution, the acetic acid concentration was 14. The alcohol concentration is 1. The stent volume %, that is, the total concentration is 15.
It became 9%. Further fermentation is continued until the acetic acid concentration reaches 15.
When the alcohol concentration reached 0.7% by volume, the moromi was taken out for about 1 hour or more in the same manner as above while adding ultra-filtration, and the amount of moromi in the fermenter 1 was reduced. When the temperature reached 20e, the ultra-sake fermentation and removal of the mash were stopped in the same manner as above, and the raw mash was immediately filled in the same manner as above.

After filling the raw material moromi, as fermentation progresses and the acetic acid concentration increases, the alcohol solution is added until the alcohol concentration in the moromi reaches 0. When the total concentration of the moromi is around 16% by adding so as not to go below the various amount%, stop adding the alcohol solution and continue the fermentation until the acetic acid concentration reaches 15% by weight/volume or more. , Complete the extraction of the moromi while adding ultrafiltration before the alcohol concentration in the moromi becomes 0.3% by volume or less, and then immediately fill the raw moromi, and perform ultrafiltration when taking out the moromi. Semi-continuous fermentation was continued while adding

In this way, the average production speed of each cycle after the addition of ultra-high filtration at the time of removing the mash was 1.7y/e/hour, 2.1f1/e/hour, and 2.6f/e/hour. It gradually started to rise.

Therefore, in the 4th cycle after the addition of ultrap-filtration at the time of taking out the moromi, the acetic acid concentration in the moromi became 8.1% by weight/volume, and from the time when the alcohol solution started to be added in the same manner as above, the dissolved oxygen meter 35 and The sensor 36 was activated to begin measuring the dissolved oxygen concentration in the moromi. At the beginning of this measurement, the dissolved oxygen concentration in the sake was 0.9 to 1.2 ppm.
However, as fermentation progressed and the acetic acid concentration in the moromi rose, the dissolved oxygen concentration gradually decreased until the acetic acid concentration reached 10. When the seed amount/volume % is reached, 0.
It was 2 to 0.4 ppm. At this point, open the valve 33 and pressure reducing valve 34 to reduce the pressure of oxygen gas to 1kg1cI.
At t, supply of oxygen gas was started.

The flow rate of oxygen gas was set to 2 e/min, and thereafter, semi-continuous fermentation was continued while supplying oxygen gas at this flow rate to aerate the air with increased oxygen concentration (in this example, the flow rate of oxygen gas was kept constant). (However, depending on the situation, this flow rate may be changed.) The acetic acid concentration in the moromi was 14.1% by weight/volume and the total concentration was 16% in the first minute after starting the supply of oxygen gas, so at this point, the addition of the alcohol solution was stopped and further fermentation was carried out. Continued.

And the acetic acid concentration of moromi is 15. When the mash amount/volume % is reached, the moromi is transferred to fermenter 1 while adding ultra-high filtration in the same manner as above.
When the amount of mash in the fermenter 1 reaches 20e, the concentration of acetic acid bacteria and the removal of the mash by the ultrafiltration device 15 are stopped, and the same raw mash as above is immediately poured into the fermenter 1 in the same manner as above. The total amount of moromi was 50e. After filling the raw material moromi, as fermentation progresses and the acetic acid concentration increases, the alcohol solution is added until the alcohol concentration in the moromi reaches 0. Add so that the amount does not exceed %,
When the total concentration of the moromi reaches around 16%, the addition of alcohol solution is stopped, and when the fermentation is continued and the acetic acid concentration reaches 15% by weight/volume or more, the alcohol concentration in the moromi becomes 0.
．． The extraction of the moromi is completed while adding an ultra-high filtration before the concentration becomes less than 3% by volume, and then the raw moromi is immediately filled, and when the moromi is taken out, an ultra-high filtration is applied and oxygen is added as described above. Semi-continuous fermentation was continued while aeration of concentrated air was carried out.

The average production rate of each cycle after supplying oxygen gas and starting ventilation of air with increased oxygen concentration as described above is 3.
．． 1y/e/hour, 3.4f/l/hour, 3.9y/e
/hour, 4.3y/e/hour, 4.5y/'/hour, 4
．． 9y/e/hour, 5.2y/e/hour, 5.6y/e
/hour, but at the 9th cycle, when the acetic acid concentration reached 10.5% by weight/volume, the dissolved oxygen in the moromi reached about 0.5 to 0.7 ppm.

Thereafter, in the ninth cycle, when the acetic acid concentration reached 15.5% by weight/volume, the mortar circulation pump 14 was operated to start taking out the mash from the fermenter 1, but at this point the ultrafiltration device If the ultrapolar filtration of the moromi by 15 is added, the dissolved oxygen concentration in the moromi will probably be 0.2pp in the next cycle.
It was expected that the value would be less than m.

Therefore, when taking out the moromi, the valve 22 was closed, and the ultrafiltration of the moromi by the ultrafiltration device 15 was not applied. However, in the next cycle, after filling the raw moromi, the concentration of acetic acid in the moromi increases to 15% by weight/volume or more, and even when it is necessary to take out the moromi and refill the raw moromi, the dissolved oxygen in the moromi increases. Since the concentration was about 0.8 to 1.0 ppm, an ultrapolar filter was added when removing the mash.

In this way, while supplying oxygen gas at a flow rate of 2e/min to aerate the air with increased oxygen concentration, the moromi is taken out with or without concentrating the acetic acid bacteria by ultrafiltration as appropriate. Semi-continuous fermentation is carried out by immediately filling the raw material moromi with the dissolved oxygen concentration in the moromi at 0.2 ppm or more, and producing vinegar of 15% by weight/volume or more at an average rate of about 4.8 q/'/hour. It lasted 19 cycles at production speed.

The moromi in the storage tank 27 obtained in this way is
The clarified moromi in the storage tank is sterilized and made into a vinegar product if necessary.

[Brief explanation of drawings]

The drawings are simplified cross-sectional views showing specific examples of the apparatus used in the present invention. 1... Fermentation tank, 2... Stirring blade, 3...
... Stirring shaft, 4 ... Electric motor, 5 ...
・Air introduction pipe, 6... Diffuser pipe, 7...
Exhaust pipe, 8... Raw material mash input pipe, 9... Mash removal pipe, 10... Serpentine pipe, 11... Mash discharge pipe, 12, 13...・・Valve, 14・・・Make circulation pump, 15・・・Extreme drinking device, 16, 1
7, 18... Vibrator, 19... Clear mash discharge pipe, 20... Mash discharge pipe, 21, 22, 23, 2
4... Valve, 25, 26, 27...
Storage tank, 28...Compressor, 29.
... Oxygen cylinder, 30, 31 ... Flow meter, 32 ... Pressure reduction valve, 33 ... Valve, 34 ... Pressure reduction valve, 35 ... ...Dissolved oxygen meter, 36...sensor.

Claims (1)

[Claims] 1. In a method for producing vinegar by a continuous fermentation method or a semi-continuous fermentation method using aerated fermentation, the moromi taken out from a fermenter is ultrafiltered by an ultrafiltration device installed outside the fermenter. The moromi is filtered into a clear moromi that does not contain acetic acid bacteria and a moromi that contains acetic acid bacteria in a higher concentration than the original state. The moromi contained in
The process of reducing the moromi to the fermenter is carried out continuously or intermittently so that the moromi is returned to the fermenter within 1 minute after it is taken out from the fermenter as a moromi containing acetic acid bacteria at a higher concentration than the original state. At the same time, the dissolved oxygen concentration in the moromi in the fermenter is reduced to 0.2p by aerating air with increased oxygen content using oxygen.
A method for producing vinegar, characterized by fermenting it at a temperature of pm or higher. 2. When the dissolved oxygen concentration in the moromi in the fermenter reached nearly 0.2 ppm, air with increased oxygen content was aerated using oxygen to bring the dissolved oxygen concentration in the moromi in the fermenter to 0.2 ppm. 2
2. The method for producing vinegar according to claim 1, wherein the vinegar is fermented at a concentration of ppm or more.