JP3188405B2 - Mushroom culture method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a method for cultivating a mushroom fungus. In cultivation of mushrooms, a sterilized medium is inoculated with an inoculum of a mushroom fungus, and after culturing the mushroom fungus for a certain period of time, some shock is applied to form a fruiting body, and the fruiting body is grown and harvested. In the cultivation of such mushrooms, it is important to prevent various bacteria from invading and spreading in the culture medium during cultivation of the mushrooms, and at the same time, to promote healthy growth of the mushrooms. The present invention relates to a method for cultivating a mushroom fungus, which can prevent various bacteria from invading and spreading in a culture medium during the culture of the mushroom fungus, and at the same time, promote healthy growth of the mushroom fungus.

[0002]

2. Description of the Related Art Conventionally, as a method for cultivating mushrooms, a method of inoculating a sterilized medium in a culture bag with a seed bacterium, sealing the upper opening of the culture bag with a sterilization filter, and culturing the mushroom bacterium is known. Is being done. In this conventional method, when sealing the upper opening of the culture bag, the culture is performed using a ring piece and a cap having an inner diameter slightly larger than the outer diameter of the ring piece and having a large number of through holes on the upper surface. A ring piece is applied to the outer periphery of the upper opening of the bag for use, the upper opening periphery of the culture bag is bent around the outer periphery of the ring piece, and a square disinfecting filter larger than the ring piece is placed thereon, Furthermore, the cap is pushed from above. However, in this conventional method, between the ring piece and the peripheral edge of the top opening of the culture bag bent to the wrinkle and between the peripheral edge of the upper opening of the culture bag bent to the wrinkle and the periphery of the sterilized filter bent to the wrinkle. Therefore, there is a drawback that, during the cultivation of the mushroom fungus, various bacteria invading from the gap adhere to the medium and spread. In order to prevent the invasion and spread of various bacteria as described above, a method of cultivating mushroom bacteria by storing a culture bag having an upper opening sealed with a sterilization filter in a container having a specific air permeability has been proposed. (JP-A-7-184474). However, in this conventional method, it takes time and effort because of the use of the storage body, and the cost is high.In particular, as a practical problem, the supply of oxygen to the medium tends to be insufficient, and the growth of mushrooms is insufficient due to environmental differences. Disadvantage.

[0003] As a method for cultivating mushrooms, there has been proposed a method in which a culture bag is not sealed with a sterilization filter.
This method forms many micropores in the culture bag itself,
These micropores are provided with a filter action of various bacteria (Japanese Utility Model Publication No. 57-22518, Japanese Patent Publication No. 2-5).
7886). However, in these conventional methods, it is very troublesome to form a large number of micropores having a filter action of various bacteria in the culture bag in the first place, and as a practical matter, it is necessary to provide the micropores with a sufficient filter function of various bacteria. In this case, the supply of oxygen to the culture medium tends to be insufficient, and the growth of mushrooms becomes insufficient.

[0004]

The problem to be solved by the present invention is that the conventional method is troublesome, expensive,
This is because various bacteria spread on the medium or the growth of mushrooms is insufficient.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a method for inoculating a sterilized medium in a culture bag with a seed bacterium and sealing the upper opening of the culture bag to culture the mushroom bacterium. , The culture bag is made of a synthetic resin having a wall thickness of 10 to 50 μm, and a hole having a diameter of 0.10 to 0.35 mm is formed in a portion forming an upper space in the bag.
Sealing the upper opening of the culture bag with a large number of 001 to 0.01% formed and forming an upper space in the bag corresponding to 1 to 4 times the volume of the sterilized medium. The present invention relates to a method for culturing mushrooms, which is a feature of the present invention.

In general, for cultivation of mushrooms, a culture bag made of a synthetic resin such as polyethylene or polypropylene is used, and the culture bag is filled with a medium, sterilized, and cooled. Next, inoculate the sterilized medium in the culture bag with the inoculum of mushrooms,
The top opening of the culture bag is sealed. In the conventional method for sealing, a sterilizing filter is used as described above, and a container having a specific air permeability is used. When a disinfecting filter is not used, a culture bag having a large number of micropores having a filter action for various bacteria is used as described above, and the upper opening of the culture bag is heat-sealed, or an aluminum piece is used. With the metal piece held as above, the periphery of the upper opening of the culture bag is bent several times and sealed with a clip, adhesive tape or the like. The temperature is 5 to 35 ° C, preferably 17 to 25 ° C, and the humidity is 30 to 90%, preferably 55.
The culture is performed under the conditions of about 65% and a surrounding airflow of 0.2 to 2.0 m / sec, preferably 0.5 to 1.5 m / sec.

In the present invention, a seed medium is inoculated into a sterilized medium in a culture bag, and the upper opening of the culture bag is sealed.
No sterilizing filter is used for sealing, and no container is used after sealing. When the upper opening of the culture bag is sealed, a space is formed above the sterilized medium in the culture bag. In the present invention, the portion forming the upper space in the bag has a diameter of 0.10-0. .35 mm, preferably 0.15
~ 0.30mm hole surface porosity 0.001 ~ 0.01
%, Preferably a large number of culture bags formed in a ratio of 0.003 to 0.008%. Such a hole can be formed as a puncture hole formed by piercing a synthetic resin culture bag with a needle, a punch hole punched out, or a hole formed by a laser beam or a chemical.

When a large number of the above holes are formed in the portion forming the upper space in the bag, various bacteria enter the upper space in the bag through the holes at the time of culture. However, under the above-described culture conditions, the inside of the bag is kept at an elevated pressure due to the generated CO ₂ and H ₂ O, so that even if the bacteria enter the upper space in the bag once, the bacteria remain in the upper space. It does not attach to the lower medium and does not spread, and is again discharged out of the bag through the hole. Bacteria that have entered the upper space in the bag are discharged out of the bag again by using the lifting pressure, thereby preventing the bacteria from attaching to the culture medium and spreading, while reducing oxygen in the air introduced into the upper space in the bag. In order to promote the growth of Mushroom fungi by incorporation into the culture medium by the diffusion, it is important to restrict the diameter of the pores forming the upper space in the bag and the surface porosity as described above. In the present invention, the diameter of the hole is
When it is a piercing hole, it means the outer diameter of the piercing portion of the used needle, and when it is a piercing hole, it means the inner diameter of the tip of the used punch. Furthermore, the surface porosity means the ratio (%) of the calculated total surface area of the pores to the surface area of the culture bag in the portion forming the upper space in the bag.

[0009] In order to take out the oxygen in the air introduced into the upper space inside the bag into the culture medium by diffusing the bacteria introduced into the upper space inside the bag using the lift pressure and discharging the oxygen from the air introduced into the upper space inside the bag, The size of the upper space in the bag formed at the top of the bag is also important. In the present invention, the upper opening of the culture bag is sealed with an upper space in the bag corresponding to 1 to 4 times, preferably 1.5 to 3 times the volume of the sterilized medium. In addition, the bacteria invading the upper space in the bag are discharged again out of the bag by using the lifting pressure, while the oxygen in the air introduced into the upper space in the bag is taken into the medium by its diffusion.
It is also important to maintain the upper space in the bag as described above. In the present invention, in order to maintain the upper space in the bag by giving the bag for culture after sealing the upper opening a corresponding degree of independence, the culture bag made of synthetic resin having a thickness of 10 to 50 μm, preferably 30 to 40 μm is used. Use bags.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention include the following 1) or 2) as preferred examples. 1) A medium for culture is filled in a polyethylene culture bag having a thickness of 40 μm, sterilized by heating under pressure, and cooled. Next, the sterilized medium in the culture bag is inoculated with Shiitake bacterium, and the periphery of the upper opening of the culture bag is bent four times while holding a rectangular flat aluminum piece, and sealed with a clip. As a culture bag, it has several times the volume of the medium to be filled,
The upper part has a large number of holes formed by piercing a needle in the upper part, but in the state sealed with the clip as described above, the upper space in the bag equivalent to three times the volume of the sterilized medium is used. A hole having a diameter of 0.20 mm (a hole formed by piercing a needle having an outer diameter of 0.20 mm at the piercing portion) is formed at a portion forming the upper space in the bag, with a surface porosity of 0.006%. In a large number. And temperature 17-25
Cultivation is performed under the conditions of a temperature of 55 ° C., a humidity of 55 to 65%, and a peripheral air flow of 0.5 to 1.5 m / sec.

2) A culture medium is filled in a polypropylene culture bag having a thickness of 30 μm, sterilized by heating, and cooled. Next, the sterilized medium in the culture bag is inoculated with shiitake bacterium, and the periphery of the upper opening of the culture bag is bent four times while holding a rectangular flat aluminum piece, and sealed with an adhesive tape. As the culture bag, one having several times the volume of the medium to be filled therein and having a large number of holes formed by piercing the needle with a slightly upper portion is used, but sealed with the clip as described above. In this state, an upper space in the bag corresponding to twice the volume of the sterilized medium is formed, and a hole having a diameter of 0.25 mm (a needle having an outer diameter of 0.25 mm at the piercing portion) is formed in the upper space in the bag. The surface porosity is 0.0
A large number are formed at a rate of 04%. And temperature 17-25 degreeC, humidity 55-65%, peripheral airflow 0.5
Culture under conditions of ~ 1.5 m / sec.

[0012]

【Example】

Test Category 1 Example 1 A medium having a composition of 90% by weight of sawdust, 5% by weight of bran, 4% by weight of rice bran and 1% by weight of corn powder and a water content of 65% by weight was placed in a polyethylene culture bag having a thickness of 40 μm. 2) Fill 2kg, sterilize by heating to medium temperature of 100 ℃
Cool. Next, 30 g of Shiitake fungi was inoculated into the sterilized medium in the culture bag, and the periphery of the upper opening of the culture bag was bent four times while holding a rectangular flat aluminum piece, and sealed with clips. did. The culture bag used had a volume several times that of the medium to be filled, and had a large number of holes formed by piercing a needle in the upper part, but sealed with clips as described above. In this state, an upper space in the bag equivalent to three times the volume of the sterilized medium is formed, and a hole having a diameter of 0.20 mm (a piercing portion having an outer diameter of 0.20 mm) is formed in a portion forming the upper space in the bag. Hole pierced with a needle)
Were formed at a ratio of 0.006% of the surface porosity. 50 bags of the same type were prepared, and these were prepared at a temperature of 17 to 25 ° C, a humidity of 55 to 65%, and a peripheral airflow of 0.5 to 65%.
The cells were cultured under the condition of 1.5 m / sec for 60 days. The medium was contaminated with various bacteria, the growth of Shiitake fungi, browning, and the condition of dew water were visually observed. These were evaluated according to the following criteria, and the results are shown in Table 1.

Bacterial contamination ◎: No germ contamination was observed at all in all 50 bags ；: Some germ contamination was observed in one bag 袋: Less than 3 bags germ contamination was observed in each part ×: More than 5 bags Growth of Shiitake bacterium is remarkably contaminated ◎; Growth of the bacterium is smooth over the entire medium in all 50 bags ○; Insufficient growth of the bacterium is partially observed in 1 to 3 bags △; Insufficient growth is observed in each part. ×: In 5 or more bags, the growth of bacteria shows remarkably suppressed formation over the entire medium. Browning ◎: Almost no browning is observed in all 50 bags. ×: Browning is observed in each part for 3 or more bags ×: Browning is remarkable over the entire medium for 5 or more bags Condensation water ◎: Almost no condensation water is found in all 50 bags ○: Condensed water is partially observed in 1 to 3 bags △: Condensed water is observed in each part of 3 or more bags ×: Condensed water is remarkable throughout the medium for 5 or more bags

Comparative Example 1 A culture bag similar to that of Example 1 was used (however, no porosity was formed).
After cooling and inoculation of the inoculum, the upper opening of the culture bag was sealed with a disinfecting filter (Tyvek, trade name, manufactured by DuPont) using a ring piece and a cap. Fifty bags were prepared in the same manner, and these were cultured under the same conditions as in Example 1. And it evaluated similarly to Example 1 and the result was shown in Table 1.

Comparative Example 2 After sealing the upper opening of the culture bag in the same manner as in Comparative Example 1, the sealed product was stored in a storage body (Luxer, trade name, manufactured by Asahi Kasei Kogyo Co., Ltd.), and a rectangular flat aluminum piece was formed. The outer periphery of the upper opening of the storage body was bent four times while holding the container, and sealed with a clip. Make 50 bags of the same thing,
These were cultured under the same conditions as in Example 1. And it evaluated similarly to Example 1 and the result was shown in Table 1.

Comparative Example 3 As a culture bag, a large number of micropores (holes formed by piercing the tip of an extremely fine needle) having a diameter of 0.02 to 0.4 μm were formed in a portion forming an upper space in the bag. An upper opening of the culture bag was sealed in the same manner as in Example 1 except that the above-mentioned one was used. Fifty bags were prepared in the same manner, and these were cultured under the same conditions as in Example 1. And it evaluated similarly to Example 1 and the result was shown in Table 1.

[0017]

[Table 1]

Test Category 2 Examples 2 to 5, Comparative Examples 4 to 7 Cultivation was carried out in the same manner as in Example 1 except that the diameter of the hole forming the upper space in the bag was changed as shown in Table 2. The top opening of the bag was sealed. Fifty bags were made in each case, and sealed under the same conditions as in Example 1. And it evaluated similarly to Example 1 and the result was shown in Table 2.

[0019]

[Table 2]

Test Category 3 Examples 6-9, Comparative Examples 8-11 The same procedures as in Example 1 were carried out except that the surface porosity of the holes forming the upper space in the bag was changed as shown in Table 3. To seal the upper opening of the culture bag. Fifty bags were made in each case, and sealed under the same conditions as in Example 1. Then, evaluation was made in the same manner as in Example 1, and the results are shown in Table 3.

[0021]

[Table 3]

Test Category 4 Examples 10 to 14, Comparative Examples 12 to 14 The upper opening of the culture bag was prepared in the same manner as in Example 1 except that the thickness of the culture bag was changed as shown in Table 4. Sealed.
Fifty bags were made in each case, and sealed under the same conditions as in Example 1. And it evaluated similarly to Example 1 and the result was shown in Table 4.

[0023]

[Table 4]

With respect to a culture bag having a thickness of 5 μm or less, an upper space in the bag could not be formed.

Test Category 5 Examples 15-18, Comparative Examples 15-18 Culture bags were prepared in the same manner as in Example 1 except that the volume ratio of the upper space in the bag to the sterilized medium was changed as shown in Table 5. Was sealed at the top opening. Fifty bags were made in each case, and sealed under the same conditions as in Example 1.
And it evaluated similarly to Example 1 and the result was shown in Table 5.

[0026]

[Table 5]

[0027]

As is clear from the above, the present invention as described above has an effect that healthy growth of mushroom fungi can be promoted at a low cost with a simple operation.

Claims (5)

(57) [Claims] 1. A method for inoculating a sterilized medium in a culture bag with a seed bacterium and culturing the mushroom bacterium by sealing an upper opening of the culture bag, wherein the culture bag has a wall thickness of 10 to 50.
A large number of holes having a diameter of 0.10 to 0.35 mm and made of a synthetic resin of μm and having a diameter of 0.10 to 0.35 mm were formed in a portion forming an upper space in the bag with a surface porosity of 0.001 to 0.01%. A method for cultivating a mushroom bacterium, comprising sealing an upper opening of the culture bag while forming an upper space in the bag corresponding to 1 to 4 times the volume of the sterilized medium. 2. The method for cultivating mushrooms according to claim 1, wherein the culture bag is made of a synthetic resin having a thickness of 30 to 40 μm. 3. The method for cultivating a mushroom bacterium according to claim 1, wherein a culture bag having a large number of holes having a diameter of 0.15 to 0.30 mm formed in a portion forming an upper space in the bag. 4. A culture bag having a large number of pores formed in a portion forming an upper space in the bag with a surface porosity of 0.003 to 0.008% as a culture bag. Culture method of mushrooms. 5. The mushroom fungus according to claim 1, 2, 3 or 4, wherein the upper opening of the culture bag is sealed with an upper space in the bag corresponding to 1.5 to 3 times the volume of the sterilized medium. Culture method.