KR100481772B1 - How to make sterile tofu in a container - Google Patents

Abstract

The present invention relates to a method for producing sterile tofu placed in a container, wherein the method preserves soymilk at 70-85 ° C. for 10-20 minutes, cools it to 30 ° C. and preserves it for 20-40 minutes, and incorporates heat resistant apo Germicidal germs, sterilized by heating the germinated soy milk for 4 seconds at 128 ~ 135 ℃, and sterilized soy milk is stored below 20 ℃, mixed with an aqueous magnesium chloride solution to the sterilized container And a solidification step of solidifying the mixed liquid in the container by heating the sealed container in a sterile atmosphere.

Description

How to prepare sterile tofu in a container

The present invention relates to a method for producing sterile tofu placed in a container, in particular, a spore of heat-resistant apolytic bacteria adhered to soybeans without sterilization without using a sterilizing agent and having good long-term storage.

Conventionally, as this kind of method, for example, as disclosed in JP-A 51-67745, soymilk is stored at 70 to 85 ° C for 10 to 20 minutes, and this is cooled to 30 to 45 ° C to 20 to 80 degrees. The germicidal heat-resistant apolytic bacteria germinated into the soymilk after being preserved for a minute are germinated, and the sterilized process of sterilizing the germinated soymilk by heating at 122 ° C. or higher and below 128 ° C. for 1 to 4 seconds, and the sterilized soy milk is stored at or below room temperature. Background Art A method comprising a filling step of mixing an aqueous solution of gluconodeltalactone and filling the resulting mixture with a sterile container under a sterile atmosphere, and a solidification step of heating the sealed container to solidify the mixed solution in the container.

Tofu obtained by the above method was difficult to sterilize, to be too soft in hardness, to have a sour taste, and so on.

The reason why the sterilization is not sure is due to the low heating temperature and the inability to completely kill the heat-resistant apolytic bacteria. As a result, long-term storage of 3 months was not possible at room temperature.

It is thought that there exists a problem in the heating conditions in a sterilization process as a cause of too soft hardness. On the other hand, it is thought that glucono-delta-lactone is used as a coagulant as a cause of the taste being sour. The reason for using gluconodeltalactone is considered to be slow release, that is, the reaction rate is slow, and the range of optimum addition amount is considerably wider than magnesium chloride.

An object of the present invention is to provide a method for producing sterile tofu that can be sterilized reliably for long-term storage and that is put in a container having good flavor at a suitable hardness.

In the method for producing sterile tofu placed in a container according to the present invention, the soymilk is stored for 10 to 20 minutes at 70 to 85 ° C, cooled to 30 ° C, and stored for 20 to 40 minutes to germinate heat-resistant follicle forming bacteria incorporated in soymilk. Sterilized by heating the germinated soy milk for 4 seconds at 128 to 135 ° C., and storing the sterilized soy milk at 20 ° C. or lower, and mixing the aqueous magnesium chloride solution therein with the aseptic container in a sterile atmosphere. And a solidification step of heating the sealed container to solidify the mixed liquid in the container.

In the method for producing sterile tofu placed in a container according to the present invention, since the heating temperature at sterilization is set at 128 to 135 ° C, sterilization is assured, and the obtained tofu is brought to an appropriate hardness.

Moreover, since magnesium chloride is used as a coagulant, a flavor-flavored tofu can be obtained compared with the tofu obtained by the conventional method which uses glucono delta lactone.

In addition, since the preservation of 70-85 degreeC in a sterilization process is performed not by reheating what was once cooled, but by cooling the soymilk heated by steam heat, the heating process of soymilk can be reduced and flavor is good. Tofu of moderate hardness can be obtained. When the soymilk is stored at 70 to 85 ° C for 10 to 20 minutes, the soymilk is treated with steam at a temperature higher than the storage temperature for about 30 minutes, and bacteria other than the apolytic bacteria are killed therebetween.

If the sterilization step is performed by cooling the soymilk, which is 85 to 90 ° C. by steam heat, at 70 to 85 ° C. and storing it for 20 minutes, shock is given to the follicle forming bacteria. Start germination

When the aqueous magnesium chloride solution used in the filling step is stored at 20 ° C. or lower, a tofu having a moderate reaction rate with soymilk and a uniform structure is produced.

When the coagulation step is carried out by passing it through a steam bath heated at 85 to 95 ° C. for 40 to 70 minutes, a structure having no coagulation unevenness is made to have uniform tofu.

Hereinafter, the present invention will be described according to Examples.

Soymilk obtained by the conventional method is brought to 85 ~ 90 ℃ by heat when steamed and boiled raw soybeans in a steam bath, it is quenched to a temperature of 70 ~ 85 ℃ by plate heat exchanger and stored for 10 to 20 minutes In order to germinate the follicle forming bacteria, the plate heat exchanger is cooled again to 30 ° C and stored for 20 to 40 minutes. Subsequently, the bubble is removed by a vacuum degassing apparatus, and it is preserve | saved for 4 second by the UHT sterilization apparatus at the temperature of 128-135 degreeC, and it heats continuously, and the germinating follicle forming bacteria are completely killed. Sterilized soymilk is quenched and stored in sterile tanks. Storage temperature is 20 degrees C or less, Preferably it is 15-17 degreeC.

Magnesium chloride is dissolved in water in a coagulant dissolution tank, sterilized by a membrane filter, cooled to the same temperature as soymilk, and stored in a sterile tank.

The soymilk and magnesium chloride stored in the tank, respectively, are separately fed to the filling machine and mixed just before filling. The amount transferred of the magnesium chloride aqueous solution is carried out by a metering pump, and is uniformly mixed with soymilk.

Aseptic chargers to be used include those having a container-forming seal type and those having a container supply type.

The process of the container-type sealing type charger is as follows. Synthetic resin wound in the form of a roll formed as a container body, a sheet laminated with aluminum foil and paper, and an adhesive tape for sealing portions are separately supplied, first sterilized through a hydrogen peroxide treatment tank, and then dried by hot air at 100 ° C. or higher. Hydrogen peroxide is completely removed. Thereafter, in the shaping / filling chamber stored at constant pressure in sterile air, the container body is first molded into an appropriate capacity and shape, and then magnesium chloride-containing soymilk is filled and sealed.

The container supply type charger is arranged on the top wall of the sterile chamber and the inlet with valve is open in the sterile chamber. And a conveyor with a plurality of containers under the inlet is to move. The interior of the sterile chamber, including the apparatus, is sterilized by spraying with hydrogen peroxide water, and then returned to room temperature after the existing air is replaced by hot air, and stored in a sterile atmosphere. The filling into the container is performed by the self loading of the soymilk and the magnesium chloride solution, and the filling time is controlled by opening and closing the valve. After filling, the lid is mechanically capped and heat sealed in the same sterile chamber.

The sealed container filled with soymilk is passed through a steam bath heated at 85 to 95 ° C for 40 to 70 minutes to solidify the soymilk in the container. Subsequently, cooling is carried out through a water bath containing cooling water to obtain tofu that has an unprecedented flavor and can be stored for a long time.

Next, the test and the result which were performed in order to determine the germination optimal condition and final sterilization temperature of apoblast-forming bacteria are demonstrated below.

Test 1

10 ml of soymilk obtained by a conventional method from a raw material is placed in a test tube, subjected to a molten stopper to autoclave, and to prepare B. subtilis to 10 ² cfu / ml. do. Heat treatment was carried out at 70 ° C, 75 ° C, 80 ° C and 85 ° C for 10 minutes for 20 minutes to adjust a total of eight types of samples. 1 ml of each of these eight types of samples was taken, and the apolytic bacteria present therein were measured by a conventional method. Subsequently, this heat-treated sample was cooled to 30 degreeC and 40 degreeC, and it preserve | saved for 20 minutes, 40 minutes, and then boiled water bath was performed for 10 minutes, and the apopocytobacteria was measured by the conventional method again. The results are shown in Table 1.

Obviously from Table 1a and Table 1b, the cooling time is best suited for 20 minutes when heat-stored at 70 ° C and 75 ° C, and the most suitable for 40 minutes for heat-storage at 80 ° C and 85 ° C. Do.

TABLE 1a

TABLE 1b

Test 2

The tofu obtained by a conventional method from the raw material was heated at 122 ° C, 125 ° C, 128 ° C, 130 ° C, 132 ° C, and 135 ° C for 4 seconds, and then tofu was made for test, and the hardness was measured. The hardness was measured by using a 10 φ adapter made of FUDOH rheometer (Leiotech Co., Ltd.) at 6 cm / min. The test results are shown in Table 2.

According to Table 2, preferable hardness was 70-90 (g), and sterilization conditions were most suitable when it was 128 degreeC, 130 degreeC, and 132 degreeC.

TABLE 2

Example

About 75 kg of soymilk was prepared by dissolving 1 bag (15 kg) of US peeled soybean (shape flakes) in 75 kg of water, heating at 105 ° C. for 4 minutes in a steamer, and removing the paper with a press machine. Solid content of soymilk was 10.2%. The temperature of this soymilk is 89 ° C, which is cooled to 75 ° C with a plate cooler for 20 minutes, imparted thermal shock to the apolytic bacteria, and further cooled to 30 ° C with a plate cooler, and stored for 20 minutes. The germ spores germinated about 88%. The germinated soy milk was placed in a degassing apparatus to remove bubbles, heated at 132 ° C. for 4 seconds with a UHT sterilizer, cooled to 20 ° C., and stored in a sterile tank.

Magnesium chloride was dissolved in the dissolution tank. A membrane filter was installed in the piping from the dissolution tank to the charger to allow sterilization. Magnesium chloride aqueous solution was uniformly mixed by injecting soymilk into a pipe conveyed from a sterile tank to a filling machine with a metering pump. The used charger is the said container formation sealing type. Using this filling machine, the container was continuously and sterilely formed, filled with magnesium chloride-containing soymilk, and sealed in a container, passed through a steam tank stored at 85 to 95 ° C. for 40 to 70 minutes, and then cooled by passing through a water tank containing cooling water. Tofu was prepared in a 200cc container of about 250 packs.

The tofu put in the container manufactured in the present example was satisfactory in flavor after being stored at room temperature for 3 months, and had good hardness and texture, and was a good product.

The method of the present invention provides a method for producing sterile tofu placed in a container having a good flavor while improving sterilization degree to enable long-term storage and at the same time maintaining appropriate hardness and tissue.

Claims (5)

Soymilk is stored at 70-85 ° C. for 10-20 minutes, cooled to 30 ° C. and stored for 20-40 minutes to germinate heat resistant follicle forming bacteria mixed in soy milk, and the germinated soy milk is heated at 128-135 ° C. for 4 seconds. Sterilization process to sterilize, A filling step of storing the sterilized soymilk at 20 ° C. or lower, mixing the aqueous magnesium chloride solution thereto, and filling and sealing the obtained liquid mixture in a sterile container under a sterile atmosphere; A method of producing sterile tofu in a container, comprising a coagulation step of heating the sealed container to solidify the mixed liquid in the container. The method for producing aseptic tofu in a container according to claim 1, wherein the sterilization step is performed by cooling the soymilk at 85 to 90 ° C by steam heat at 70 to 85 ° C and storing it for 10 to 20 minutes. The method for producing sterile tofu in a container according to claim 1 or 2, wherein the aqueous magnesium chloride solution used in the filling step is stored at 20 ° C or lower. The method for producing sterile tofu in a container according to claim 1 or 2, wherein the solidification step is performed by passing the solidification step through a steam bath heated to 85 to 95 ° C for 40 to 70 minutes. The method for producing aseptic tofu in a container according to claim 3, wherein the solidification step is performed by passing the solidification step through a steam bath heated to 85 to 95 ° C for 40 to 70 minutes.