JPH0215190B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing high quality vinegar in a simple manner and in an extremely short period of time. Several methods are known for producing vinegar. For example, a moromi (hereinafter referred to as vinegar moromi) consisting of alcohol-containing raw sake, nutritional substances of acetic acid bacteria, and vinegar seeds is aerated and stirred in a closed fermentation tank. However, in the so-called submerged aeration agitation method, which produces vinegar using a deep fermentation method, fermentation proceeds even inside the liquid, so compared to the static method (flat fermentation method), the equipment capacity per fixed floor area is larger. Also, it has the advantage of being able to be brewed quickly, but since the vinegar mash comes into contact with air bubbles in the fermentation tank, the excellent aroma of the raw alcoholic beverage that is the ingredient is lost, and unnecessary oxidation reactions occur. It has the disadvantage that it produces unpleasant aromas and tastes, making it difficult to obtain high-quality vinegar. In addition, the so-called drip fermentation method, in which a cylindrical fermentation tower is filled with carriers on which acetic acid bacteria have grown, and the vinegar moromi and air are allowed to pass through this packed bed, is also effective for rapid fermentation because the vinegar mortar is brought into contact with the air. However, like the above-mentioned intra-liquid aeration stirring method, high-quality vinegar cannot be obtained, and due to the non-uniformity of the packing density of the packed bed, the flow of vinegar mortar and air passing through the packed bed in contact with each other is poor. Non-uniformity causes drifting of the flow, creating dead spaces in some parts of the packed bed, and in areas where the vinegar mixture passes through a lot of contact, the acetic acid bacteria film layer that has grown on the surface of the carrier particles is destroyed and washed away, which significantly inhibits fermentation. On the other hand, vigorous fermentation cannot be sustained in areas where there is little or no contact passage, so vinegar cannot be obtained efficiently as a whole. In contrast, the static fermentation method has the advantage of producing high-quality vinegar with excellent aroma and taste because the vinegar mash does not come into unnecessary contact with air, but on the other hand, it requires a large horizontal surface. Because the fermentation is carried out in the factory, the production volume per unit area of the factory is extremely small, and it has the major drawback that it cannot be brewed quickly. Therefore, in view of the current situation, the inventors of the present invention believe that it is necessary to bring vinegar moromi into contact only with acetic acid bacteria, without directly contacting it with air. As a result of various studies on how to obtain high-quality vinegar very easily and in a very short period of time, we found that in a fermentation tank,
A large number of porous carrier membranes on which acetic acid bacteria are attached are arranged vertically or tilted, and vinegar mortar is supplied to the upper part of the carrier membrane and permeates, flows down the carrier membrane, and comes into contact with the acetic acid bacteria to perform acetic acid fermentation. The present invention was completed on the basis of this knowledge. That is, the present invention involves arranging a porous carrier membrane on which acetic acid bacteria are attached vertically or obliquely in a fermentation tank, supplying vinegar moromi to the upper part of the carrier membrane, penetrating it, and flowing down the inside of the carrier membrane. , is a method for producing vinegar characterized by carrying out acetic acid fermentation in contact with the acetic acid bacteria. The present invention will be explained in detail below. FIG. 1 is a schematic longitudinal sectional view showing one specific example of a vinegar manufacturing apparatus for carrying out the present invention. In FIG. 1, 1 is a fermentation tank, in which a carrier membrane 2 on which acetic acid bacteria are attached is arranged. The shape of the carrier membrane used here is arbitrary, such as flat, cylindrical, etc., as long as it is generally suitable for carrying out the present invention. Also, the membrane may be used alone,
It may also be used by laminating it on a porous support or a frame-shaped support. Further, the number of carrier films may be one, but a large number may be arranged and used at appropriate intervals. In this case, the spacing between the carrier films varies depending on the shape and size of the carrier film, how it is installed, the capacity of the blower, etc., but it is preferable to ensure sufficient air circulation. The carrier membrane is then arranged tilted to one side, preferably vertically. By arranging it in this way, the vinegar moromi supplied and permeated into the upper part of the carrier membrane naturally flows from the upper part to the lower part of the carrier membrane, and
It is possible to carry out acetic acid fermentation by contacting the acetic acid bacteria that have grown on the carrier membrane. It is desirable that the rate of supply of the vinegar mortar to the upper part of the carrier membrane is within a range that does not exceed the permeation rate of the vinegar mortar into the carrier membrane. In other words, if vinegar is supplied in an amount exceeding the amount permeated into the carrier membrane per unit time, the excess amount of vinegar will overflow from a part of the carrier membrane, and the acetic acid bacteria film that has grown on the carrier membrane will be destroyed. Since the layer is destroyed and washed away, there is a risk that acetic acid fermentation will not be able to continue vigorously in that area. As a means for supplying and infiltrating the upper part of the carrier membrane with vinegar moromi, as shown in the figure, a fermentation tank 3 is provided above the fermentation tank, and a through groove 4 is provided in the bottom wall of the tank 3, which closely fits with the upper end of the carrier membrane. Alternatively, a through hole is provided, the upper end of the carrier film is brought into close contact with the groove (or hole), the groove is closed, the moromi is supplied from the moromi supply pipe 5 to the mortar retention tank 3, and the upper end of the carrier film is filled with vinegar. A method of dipping the upper end of the carrier film in vinegar may be used, or a method of dropping or injecting vinegar mortar onto the upper part of the carrier film using a mortar dispersion pipe etc. is preferable because it allows the vinegar paste to be supplied to the carrier membrane without considering the permeation rate of the vinegar paste in the carrier membrane. Next, it is important that the surface of the carrier film is made of a material on which acetic acid bacteria can easily adhere to it. Examples of such materials include cloth and water-insoluble paper that are porous and have a thickness of several millimeters, and lipophilic (hydrophobic) nonwoven fabric and thick cloth are particularly preferred. Specific examples of thick nonwoven fabrics include WOSEP (manufactured by Toyo Rayon Co., Ltd.);
Examples of thick cloths include Toughnel Oil (manufactured by Mitsui Petrochemicals) and TEIJIN-OLSORB (manufactured by Teijin Corporation), and cotton flannelette as specific examples of thick cloths. Next, as a method for attaching acetic acid bacteria to the carrier film, 10 to 20% of the carrier film is placed in vinegar mortar inoculated with acetic acid bacteria.
A method of soaking for a few seconds and then lifting it into the air for a few seconds to several minutes is repeated for several days at a suitable temperature for the growth of acetic acid bacteria, and a method of infiltrating vinegar moromi inoculated with acetic acid bacteria from the upper end of the carrier membrane to infiltrate the inside of the carrier membrane. Examples include a method in which the solution is allowed to flow naturally from top to bottom and leached and dripped from the lower end of the carrier membrane for 20 to 30 hours at a temperature suitable for the growth of acetic acid bacteria.
In this way, acetic acid bacteria can be sufficiently attached to the carrier membrane. The acetic acid bacteria that have grown on this carrier film can be used repeatedly. In the case of batch fermentation, the lag phase is hardly observed from the second fermentation, and when vinegar mash is supplied, acetylation (the action of oxidizing alcohol to acetic acid, hereinafter the same) occurs in a short time. ) begins. Furthermore, even if the supply of vinegar moromi is temporarily stopped due to a malfunction of the equipment, the acetic acid bacteria will not die, and if vinegar mortar is supplied again, vigorous fermentation will start again. The oxidation rate of the carrier film on which the acetic acid bacteria have adhered is not much different from the acetylation rate of the bacterial film in the conventional static fermentation method when converted per unit area. As a result, the bacterial membrane area can be significantly increased compared to conventional static fermentation methods, and the fermentation period can be significantly shortened. Next, examples of the vinegar moromi used in the present invention include vinegar moromi prepared according to a normal vinegar manufacturing method, such as alcoholic beverages such as Japanese sake and grape wine, potatoes, etc.
Examples include alcohol-containing brews obtained by saccharification and alcohol fermentation of grains as raw materials, and alcohol-containing aqueous solutions to which acetic acid bacteria nutrients (for example, sake lees infusion) are added. The moromi after acetic acid fermentation drips out from the bottom of the carrier membrane and accumulates at the bottom of the fermentation tank.
The mash is taken out from the mash discharge pipe 6, and vinegar mash corresponding to the taken out mash is supplied to the mash retention tank 3 on the fermentation tank, so that vinegar can be continuously produced. In addition, if fermentation is not completed after the vinegar moromi flows down the carrier membrane once, the carrier membrane may be tilted instead of vertically, the shape of the carrier membrane may be widened toward the bottom, or the carrier membrane may be The acetic acid fermentation can be completed by increasing the contact time, contact amount, and contact area between the acetic acid bacteria and the vinegar mash by making the structure of the acetic acid bacteria denser. Furthermore, if the acetic acid fermentation cannot be completed by passing the vinegar moromi through the carrier membrane once, the moromi that has leached and dripped to the bottom of the fermentation tank is taken out from the moromi discharge pipe 6 and then transferred to the pipe 8 and the middle. By the action of the provided circulation pump 7, the mash is returned to the mash supply pipe 5, and by performing circulation fermentation, it is possible to obtain the mash which has undergone acetic acid fermentation. Next, the fermented mash obtained in this way is taken out of the fermentation tank, and then subjected to aging, filtration, and standardization of ingredients, followed by sterilization to produce a product according to the usual method of manufacturing vinegar. As is clear from the above explanation, the present invention does not involve violently contacting the vinegar moromi with bubbles or air as in the conventional submerged aeration stirring method and the dripping fermentation method, but rather acetic acid is produced inside the porous carrier membrane. This method brings the bacteria and the vinegar moromi into static contact, prevents the vinegar mortar from coming into direct contact with the air as much as possible, and rapidly acetylates the acetic acid bacteria, similar to the intra-liquid aeration stirring method. The excellent aroma of the ingredient sake is not lost, and the vinegar moromi does not unnecessarily come into contact with air and oxidize, resulting in unpleasant aromas and tastes. Very high quality vinegar can be obtained in a very short period of time using simple equipment. The present invention will be explained in more detail below with reference to Examples. In Figure 1, fermentation tank 1 is 40 cm long and 26 cm wide.
The carrier membrane 2 is placed on both sides of a 2 mm thick vinyl chloride carrier membrane support frame having the shape shown in FIG. A non-woven cloth (manufactured by Toyo Rayon) is pasted on the surface, and acetic acid bacteria are evenly and sufficiently attached to the surface17
(the effective total area of the carrier membrane is about ^15000cm2 )
The through grooves 4 are installed in the bottom wall of the fermentation tank 3, and are set up with their upper ends aligned almost vertically at 10 mm intervals.
The upper end of the carrier membrane is inserted to create a structure that does not leak water, and "a means for returning the moromi leached from the lower part of the carrier membrane to the fermentation tank as vinegar mortar" is connected to the opening of the mortar discharge pipe 6 and the mortar. The opening of the supply pipe 5 was connected to the opening of the supply pipe 5 by a pipe 8 equipped with a circulation pump 7, as shown in FIG. Incidentally, the amount of circulation of the moromi by the circulation pump 7 was made equal to the natural fall amount of the moromi that leached out and dripped from the lower end of the carrier membrane. Next, vinegar moromi 20 [acidity 1% (W/
V), alcohol 5% (V/V)] was added, the temperature inside the fermentation tank was maintained at approximately 30℃, and batchwise acetic acid fermentation was started while circulating the moromi, and oxidation was completed in approximately 40 hours. Vinegar with a final acidity of 5.5% was obtained. The change in acidity over time at this time is as shown in FIG. For comparison, 20% of the same vinegar mash was added to the fermentation tank used in the above method, and vinegar was produced using the normal static fermentation method while maintaining the temperature inside the fermentation tank at approximately 30℃, and the acetylation was completed. It took about one month to complete the process, and vinegar with a final acidity of 5% was obtained. Next, a panel of 20 people was trained to distinguish between the vinegar obtained by this static fermentation method and the vinegar obtained in this example (the present invention) (both of which had acidity adjusted to 5% with water). When compared by a sensory test, the results shown in Table 1 were obtained.

[Table] (Note) -: No significant difference.
From this result, in the case of the ordinary static fermentation method, it takes about one month to complete the oxidation, but when using the present invention, it takes only about 40 hours, which means that vinegar can be obtained in a very short period of time. The vinegar obtained by
Compared to vinegar obtained by the static fermentation method, which produces the highest quality vinegar with the best aroma and taste among the various vinegar production methods, this method yields high quality vinegar with even better aroma, taste, and overall taste. I understand that.

[Brief explanation of drawings]

FIG. 1 is a longitudinal schematic explanatory view showing a specific example of a vinegar manufacturing apparatus for carrying out the present invention, FIG. 2 is a carrier support frame that supports the carrier membrane of the present invention, and FIG. The carrier film and FIG. 4 are diagrams showing changes in acidity over time, respectively. DESCRIPTION OF SYMBOLS 1... Fermentation tank, 2... Carrier membrane, 3... Mortem retention tank, 4... Penetration groove, 5... Morté supply pipe, 6...
...mash discharge pipe, 7...circulation pump, 8...pipe.

Claims (1)

[Claims] 1. In a fermentation tank, a porous carrier membrane on which acetic acid bacteria are attached is arranged vertically or inclinedly, and vinegar moromi is supplied to the upper part of the carrier membrane and allowed to flow down inside the carrier membrane. A method for producing table vinegar characterized by carrying out acetic acid fermentation in contact with.