JP3694061B2 - Methods for preventing contamination of bacteria in solid culture - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a method for preventing contamination of bacteria in culturing solid culture raw materials (hereinafter abbreviated as culture raw materials).
[0002]
[Prior art]
Conventional culture raw materials can be cultured by a cooling process in which air is supplied from above while the heat-treated culture raw material is loaded on a transfer belt conveyor and then naturally cooled, or a solid culture device (hereinafter referred to as a culture device). Air is used in various places, such as a culture process in which air is blown to the culture raw material. This air is drawn directly from the outside air or through a filter, but is usually used without any treatment.
[0003]
Further, in the washing step of the culture apparatus after use, it is usually washed with water and dried with hot air, and in some cases, heat sterilization treatment with steam is added.
[0004]
[Problems to be solved by the invention]
Even in the past, preventing adherence of various bacteria to the culture raw material is an essential condition for realizing solid culture well. However, in the conventional cooling process of the culture raw material, there is a possibility that various germs are mixed in the air taken in from the outside air, and the above conditions are not always observed.
[0005]
In addition, in the culture process, it is impossible to avoid the risk of contamination by air that is sucked through the filter. This is not only due to the performance of the filter, but also the culture apparatus itself is difficult to sterilize sufficiently by the washing process, especially the complicated mechanism parts, that is, the air conditioner and duct, are difficult to wash, and the remaining dirt is the propagation of various bacteria. Because it was helping.
[0006]
Therefore, in each process of culturing the culture raw material, not only the air taken from the outside air is sterilized, but also the culture raw material cooling process, the culture process and the culturing apparatus cleaning process in order to prevent the contamination of the culture raw material. Therefore, it was decided to investigate methods for preventing contamination of solid culture in solid culture.
[0007]
[Means for Solving the Problems]
What was developed as a result of the study was a method for preventing contamination of bacteria using ozone. The first is a method for preventing contamination of solid culture in solid culture, in which air containing ozone (hereinafter referred to as ozone air) is supplied to the culture raw material in the cooling step of the heat-treated culture raw material. Ozone air is generated by generating ozone in the air taken from outside air or by mixing separately generated ozone.
[0008]
The second is a method for preventing contamination of germs in solid culture, wherein ozone is supplied to the air taken into the air-conditioning path in the culture step of the culture raw material. In this case, an ozone generation mechanism may be provided at the air intake port of the air conditioning path, and an ozone decomposition mechanism may be provided between the ozone generation mechanism and the culture raw material.
[0009]
Third, in the washing step of the culture apparatus, ozone air or water containing ozone (hereinafter referred to as ozone water) is brought into contact with the inside of the culture apparatus or the air-conditioning path, and the method for preventing contamination of solid culture in solid culture It is. Ozone air or ozone water may be used during cleaning or after cleaning.
[0010]
[Action]
The present invention aims to prevent direct or indirect contamination of culture raw materials by utilizing the bactericidal action of ozone. The air taken from outside air has a risk of carrying various germs in the cooling process of the culture raw material, but in the present invention, the ozone contained therein kills the germs even if they are transported. Moreover, since germs mixed in the culture material are also killed, contamination of the culture material can be prevented.
[0011]
There is also a risk of contamination by germs in the culture raw material being cultured inside the culture apparatus because air taken from outside air is ventilated for cooling. The ozone generation mechanism provided at the air intake port of the air conditioning path supplies ozone to the air taken in from the outside air and kills germs in the air. Although ozone air has little effect on useful bacteria in the culture raw material, by providing an ozonolysis mechanism between the culture raw material and the ozone generation mechanism, only sterile air can be supplied to the culture raw material.
[0012]
The culture apparatus or air conditioning path cannot be cleaned completely due to the complexity of the structure. In the present invention, from this viewpoint, by sterilizing the apparatus or the path with ozone at the same time as cleaning, the generation and propagation of various bacteria are prevented, and the culture apparatus or the air-conditioning path with extremely high sterility is obtained. This is because ozone can be fed into places where the washing water does not reach, for example, details of the air conditioning path.
[0013]
Each of the above methods can be used independently, but by using them together, it is possible to prevent contamination of the culture raw material in a series of steps and to obtain a clean culture environment.
[0014]
【Example】
Hereinafter, examples of the method for preventing contamination of germs of the culture raw material of the present invention will be described with reference to the drawings. FIG. 1 is a side view of a cooler 1 that cools by spraying ozone air while transferring a heat-treated culture raw material. The cooler 1 closes the net conveyor 2 with a hood 3 to form a closed space 4. An air intake 6 incorporating an ozone generation mechanism 5 is provided above the closed space 4. Ozone air is sprayed onto the culture material to be transferred. For example, for steamed defatted soybeans transferred at 4 t / h, ozone air may be sprayed at a rate of 150 m ³ / min. In this example, since ozone is generated in the air taken in from the outside air, ozone can be contained almost uniformly in the ozone air, and the sterilization action by ozone can be expected in the entire closed space 4.
[0015]
The bactericidal action by ozone works directly on the culture raw material and is effective in preventing the contamination of the culture raw material, and indirectly prevents the contamination of the cooler 1 to ensure a clean cooling process. After the cooling step, the cooler 1 is washed, but if washing is insufficient, there is a possibility that various germs will propagate on the cooler 1. Therefore, after cleaning, ozone air may be further blown to sterilize.
[0016]
FIG. 2 is a cross-sectional view of a culture apparatus 14 in which the cleaning pipe 8 of the rotating bed 7 is connected to the tank 9 of ozone water, and the ozone generation mechanism 12 and the ozone decomposition mechanism 13 are added to the air intake 11 of the air conditioning path 10. . The washing pipe 8 is for mainly washing the rotating bed 7 by discharging or spraying washing water from below while rotating the rotating bed 7 after discharging the cultured raw material. In this embodiment, first, normal water is discharged and washed over the entire lower surface of the rotating bed 7, and then ozone water adjusted to 5 mg / l is sprayed to sterilize. After washing, ozone air can be circulated from the air conditioning path 10 to dry the rotating bed 7 while further sterilizing it.
[0017]
The ozone generation mechanism 12 provided in the air intake port 11 of the air conditioning path 10 sterilizes the introduced air and blows aseptic air to the culture raw material. There is a distance between the air intake 11 of the air conditioning path 10 and the rotating bed 7 on which the solid culture raw material is spread, and the influence of useful ozone in the culture raw material by ozone is usually not a problem. By decomposing the air, only aseptic air can be blown to the culture apparatus 14.
[0018]
As described above, the ozone generation mechanism 12 provided at the air inlet 11 of the air conditioning path 10 can be used in both the washing process and the culturing process. However, since the purpose is to circulate ozone air in the cleaning process, the operation of the ozone decomposition mechanism 13 is not required, and ozone having a relatively high concentration is required. Further, in the culturing process, it is only necessary to sterilize the taken-in air, and therefore, ozone having a relatively low concentration may be used. In some cases, the ozonolysis mechanism 13 is operated.
[0019]
The culture raw material using the ozone of the present invention or the bacterial contamination prevention method of the culture apparatus is effective even when used individually, but by linking all together, the culture raw material is cultured in an extremely clean and sterile state. Can be realized. In addition, the above method has an advantage that can be realized without significant changes to the conventional apparatus.
[0020]
【The invention's effect】
According to the present invention, a series of steps from the heat treatment to the end of the culture can be performed aseptically for the culture raw material, and an extremely good culture can be realized. Can be secured.
[0021]
Conventionally, since the culture raw material has been processed in a relatively closed space, a sufficient effect of ozone can be obtained only by adding a simple ozone generation mechanism to the apparatus, and newly generated equipment costs can be suppressed. Thus, it can be said that the present invention realizes high cost-effectiveness.
[Brief description of the drawings]
FIG. 1 is a side view of a cooler to which a method for preventing contamination of germs of the present invention is applied.
FIG. 2 is a cross-sectional view of a culture apparatus to which the method for preventing contamination of germs of the present invention is applied.
[Explanation of symbols]
1 Cooler 5 Ozone generation mechanism 6 Air intake 8 Wash pipe
10 Air conditioning route
11 Air intake
12 Ozone generation mechanism
14 Incubator

Claims (2)

Solid culture Oite the cooling process of the heat treated solid culture material, heat-treated raw material supplying air containing ozone in the raw material while being transported on the endless belt belt, characterized by cooling the raw material For preventing contamination of bacteria.   In the culture process of blowing to the deposited solid culture raw material, ozone is supplied to the air outside the solid culture apparatus taken into the air-conditioning path from the air intake of the solid culture apparatus, and a method for preventing contamination of germs in solid culture .

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