JPH0257886B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for cultivating basidiomycetes, and in particular to a method for cultivating basidiomycetes that can obtain fruiting bodies in a short period of time and at a high yield while preventing contamination of the culture medium with harmful bacteria. Traditionally, basidiomycetes such as shiitake mushrooms are produced by mixing nutritional substances such as rice bran with woody materials such as sawdust, adding an appropriate amount of water to prepare a culture medium, covering this with a synthetic resin film and sterilizing it, and then inoculating the seed fungus. A so-called artificial cultivation method is known in which fruiting bodies are obtained by cultivation under a suitable environment. However, in this method, as the basidiomycete continues to be cultured, the moisture in the culture medium increases due to the respiration of the bacteria, and this respiration-produced water fills the voids in the culture medium, and the culture medium becomes oxygenated. The mycelium becomes deficient and its vitality decreases significantly, and the humidity within the culture medium increases, resulting in a "stuffy" phenomenon.
Since this provides a favorable environment for the proliferation of harmful bacteria, especially Trichoderma, it has the disadvantage that contamination with harmful bacteria occurs during culture, and the fruiting bodies of Basidiomycetes often end without being formed. In addition, the above method is insufficient to supply oxygen, that is, air, necessary for the growth of basidiomycetes, and to remove respiratory gases such as carbon dioxide that are generated as the basidiomycetes grow. It has the disadvantage that the cultivation period is prolonged due to the growth inhibiting effect due to accumulation, and the yield of fruiting bodies is reduced. In addition, in order to solve this drawback, by providing many small air holes in the above synthetic resin film, it becomes easier to supply oxygen and discharge carbon dioxide gas.
Although the "stuffiness" phenomenon is improved, the evaporation of water in the culture medium is accelerated and the culture medium dries out, and harmful bacteria can also invade the culture medium through the air holes in the synthetic resin film, inhibiting the growth of mycelia, and It has the disadvantage that it has a great negative effect on the quality and yield of the fruit, and that cultivation becomes impossible halfway through. Therefore, the present inventors have conducted various studies to develop a method for cultivating basidiomycetes that does not have such drawbacks, and as a result, we have found that the method is made of two or more porous synthetic resin sheets, and that between adjacent sheets, one of the By covering the culture medium with a packaging sheet in which each hole in the sheet does not substantially overlap with each hole in the other sheet, excessive transpiration of the culture medium water during culture, contamination by harmful bacteria, etc. can be prevented, and the culture medium can be He learned that it was possible to obtain fruiting bodies of Basidiomycetes in a short period of time with good yield by properly supplying oxygen to the culture medium and discharging carbon dioxide gas from the culture medium to prevent the phenomenon of "stuffiness" in the culture medium. Based on this, the present invention was completed. That is, the present invention covers a culture medium with a packaging sheet that is composed of two or more porous synthetic resin sheets, and in which the holes in one sheet do not substantially overlap with the holes in the other sheet between adjacent sheets. This is a method of cultivating basidiomycetes, which is characterized by cultivating them. The present invention will be explained in detail below. Examples of the synthetic resin sheet used in the present invention include films and sheets formed from synthetic resins such as polyethylene, polyvinyl chloride, polypropylene, polystyrene, polycarbonate, or copolymers and blend polymers thereof. It is also possible to use one or more of these, or a laminate of them and a metal foil such as aluminum foil. In the present invention, on the synthetic resin sheet described above, a rupture port or crack is formed by piercing the needle of a roll or a looplet with needles embedded in the peripheral wall, or
Either use a punch to make a hole, or
A porous synthetic resin sheet is obtained by making intermittent cuts with something like a cutter knife. The pore diameter of the above-mentioned porous synthetic resin sheet is preferably set to a size that does not allow the constituent materials of the culture medium, such as sawdust, bran, etc., to pass through, and specifically, 1 mm or less is particularly preferred. In addition, as mentioned above, the shape of the hole includes the rupture port (crack mouth), perforation, and cut, but in the case of a rupture port (crack mouth), the exchange of oxygen gas and carbon dioxide gas is carried out at the rupture port (crack mouth). Although this is optionally carried out through a fissure, the fissure is usually closed, which is preferable because there is little intrusion of harmful bacteria from the outside and the culture medium is less likely to be contaminated. Next, two or more of the porous synthetic resin sheets described above are stacked, and each hole in one sheet substantially overlaps with each hole in the other sheet between the sheets that are adjacent to each other vertically, horizontally, or internally and externally. Obtain the packaging sheets by shifting them from each other so that they do not overlap. In the present invention, this description is extremely important, and even when there is only one porous synthetic resin sheet, or when two or more sheets are used in a superimposed manner, each hole in one sheet is different from that in the other sheet. If the pores overlap with each other, as mentioned at the beginning, the culture medium will dry out due to excessive transpiration of the culture medium water, and harmful bacteria will invade the culture medium through the pores of the porous synthetic resin sheet, resulting in basidiomycete hyphae. It damages the growth of the fruit, has a great negative impact on the quality and yield of the fruiting bodies, and the culture medium rots midway through, making it impossible to continue the culture. On the other hand, as in the present invention, a packaging sheet is made of two or more porous synthetic resin sheets, and each hole in one sheet does not substantially overlap with each hole in the other sheet between adjacent sheets. When covering the culture medium, it is necessary to supply oxygen necessary for the growth of basidiomycete hyphae, remove carbon dioxide gas generated during growth, and remove excess moisture generated in the culture medium due to the respiration of basidiomycetes. As it is moderately transpired into the outside air, the culture medium is always a suitable environment for the growth of basidiomycete hyphae, and the hyphae spread quickly and uniformly within the culture medium, allowing fruiting bodies to be obtained in a short period of time and in good yields. Can be done. And, most importantly, each pore opening in one sheet is closed by a non-opening in the other sheet, so that harmful bacteria that spoil the culture medium or fungus bed can escape from the pores in the outer sheet. Even if the microorganisms adhere to the culture medium, they must move between the sheets that are in close contact with each other in order to invade the culture medium, and as a result, there is an advantage that contamination by the harmful microorganisms can be significantly prevented. In the present invention, since the packaging sheet is made of two or more porous synthetic resin sheets stacked together, some of the many holes provided on one sheet slightly overlap with the holes on the other sheet. Although this may be unavoidable, it should be kept to the extent that contamination with harmful bacteria can be prevented to the maximum extent possible. As for the number of holes in the porous synthetic resin sheet, it is preferable to increase the number of holes in the sheet on the culture medium side, especially in the sheet in contact with the culture medium, than in the sheet on the outside air side, since this allows mycelia to spread evenly. In addition, the larger the number of porous synthetic resin sheets, that is, 2
Three sheets can more effectively prevent the invasion of harmful bacteria than one sheet. Furthermore, an air-permeable material such as a wrap or nonwoven fabric may be interposed between the sheets. Next, when covering the culture medium with a packaging sheet, the shape of the culture medium is as follows:
Alternatively, depending on the shape of the bag, any shape may be used, such as a rectangular parallelepiped, a cube, a semicylindrical shape, a cylindrical shape, a bell shape, and the like. Next, in order to carry out the present invention, the culture medium is coated and sterilized with the above-mentioned packaging sheet, and then the seed culture is inoculated.
The following cultivation is carried out according to the usual cultivation method for basidiomycetes. Alternatively, the culture medium is placed in another packaging container, packaging bag, or device, inoculated with seed bacteria, cultured for an appropriate period of time, for example, until basidiomycete fungi spread, and then taken out and covered with the above-mentioned packaging sheet, The following cultivation is carried out according to the usual cultivation method for basidiomycetes. That is, examples of the basidiomycete to which the basidiomycete cultivation method of the present invention is applied include enokitake, oyster mushroom, nameko, shiitake, tamogitake, kuritake, versicolor, Hiirotake, stone mante, and enameled mushroom. not limited to. In addition, the culture medium used in the present invention may be mainly made of one or more types of wood materials such as sawdust, vegetable fibrous materials such as bagasse, rice husks, pods, and straw; Examples include those to which fungal nutritional substances are added, but there are no limitations as long as it is a culture medium that is commonly used for cultivating basidiomycetes. In addition to the above-mentioned sawdust, the above-mentioned wood raw materials include, for example, beech, Quercus serrata, Quercus oak, Date birch,
Trees such as oak, hornbeam, cherry, styrax, poplar, alder, oak, Japanese chinquapin, tab, and teak are crushed or crushed using a conventional crusher, or are made into flakes using a plane, a slicer, or the like. At this time, if the tree is crushed or split,
It is preferable that the grain size is finer than about 4 mesh, and the wood flakes have a thickness of about 3 mesh.
It is preferably 1 mm or less, preferably 1 mm or less. Nutrient substances for basidiomycetes added to the above-mentioned main ingredients include nitrogen sources such as rice bran, corn bran, corn staple liquor, wheat gluten, amino acids, soybean meal, and soy sauce lees; carbon sources such as glucose and malt extract; monopotassium phosphate; Examples include minerals such as carbonated coal and magnesium sulfate; combinations of one or more selected from vitamins and the like. It is preferable to adjust the moisture content of the culture medium to 55 to 75%. In addition, when inoculating and culturing basidiomycetes, "hyphal aggregates" are grown on the surface of the culture medium at a specific temperature, e.g., 18-25°C, and humidity, e.g., 60-70%, depending on the type of individual basidiomycetes. The development of fruiting bodies subsequent to culturing is carried out by holding for a sufficient period of time for formation, and the development of fruiting bodies following culturing is carried out at specific temperatures, such as 10 to 20°C, humidity, and For example, at 80-90%, fruiting bodies are generated and maintained until they are fully grown. In regions and locations where the environmental humidity is high and in all seasons, basidiomycetes and hyphae are prevalent in the culture medium, and culture media that have a certain degree of resistance to contamination with harmful bacteria may be prepared using porous synthetic resin that is in contact with the outside air surface, if necessary. By partially removing the resin sheet, cultivation management can be carried out according to the environment. In addition, when fruiting bodies are formed, the packaging sheet of the present invention is removed in advance to prevent the shape of the fruiting bodies from deforming, and the fruiting bodies can be produced naturally or by a normal process such as submersion in water to ensure that the fruiting bodies are of good quality. It is possible to form a substance and harvest it. As is clear from the above description, the present invention consists of two or more porous synthetic resin sheets, and between the sheets that are separated from each other, the holes in one sheet do not substantially overlap with the holes in the other sheet. Cultivating by covering the culture medium with a packaging sheet has the following advantages. (1) Basidiomycetes, which have aerobic properties, can easily supply oxygen necessary for the growth of basidiomycetes such as shiitake mushrooms and nameko mushrooms, and easily discharge absorbed gases such as carbon dioxide gas generated during growth. Fungi grow vigorously without being affected by carbon dioxide gas. (2) As Basidiomycetes grow, the moisture content in the culture medium increases due to the breathing method, but when the culture medium is covered with a conventional film sheet that does not have air holes, this respiration-produced water is absorbed into the voids within the culture medium. The inside of the culture medium becomes oxygen-deficient,
The vitality of the hyphae is significantly reduced, and the humidity in the culture medium is high, creating an environmental condition that is favorable for harmful bacteria, especially Trichoderma, to flourish, resulting in harmful bacterial contamination during cultivation and the fruiting bodies of basidiomycetes. However, according to the method of the present invention, the moisture in the culture medium is appropriately evaporated, and the growth of basidiomycete fungi is suppressed in a culture medium with a moisture content that is optimal for the propagation of basidiomycete hyphae. can be cultivated. (3) Even if contaminant bacteria adhere to the surface of the outer sheet, the pores of the sheet are closed by the inner sheet, and by the time they enter the culture medium, the two sheets are in close contact with each other. Since it is necessary to move through the gaps, the frequency of contamination with harmful bacteria can be reduced. (4) In addition, the present invention allows cultivating basidiomycetes while maintaining the culture medium in an optimal condition for the growth of basidiomycete hyphae. Yield can be increased. Hereinafter, the present invention will be explained in more detail by showing examples. Example 1 A high-speed film was made into a bag with a diameter of 15 cm and a height of 20 cm by punching holes in a checkerboard shape of 2 cm on each side using a sewing machine.Beech sawdust 5 and raw rice bran 0.5 were added to the bag.
Add a culture medium prepared by adding water to 60% moisture and mix at a pressure of 1/Kg/cm ² and a temperature of 120°C.
After sterilizing the cells with saturated steam for 90 minutes, they were cooled to room temperature and inoculated with shiitake seed fungus (Kawamura Edible Bacteria Research Institute S54) (control). A culture medium prepared with 60% moisture was placed in a double bag made by stacking Hi-Zex film with holes punched vertically at 5 cm intervals on top of the film, sterilized, cooled, and inoculated with shiitake mushroom starter ( Present invention 1). Also, a total of 90 holes with a diameter of 2 mm, 10 rows vertically and 9 rows horizontally.
Make holes of about 100 lbs. with an incense stick, and place them in a double bag of high-speed film with a diameter of 15 cm and a height of 20 cm, which has been processed so that each hole on one sheet does not overlap with each hole on the other sheet, and the water is 60%. A culture medium prepared by adding water was added, sterilized, cooled, and shiitake seed fungi were inoculated (invention 2). In addition, the high-speed film of the above (invention 2) is made into three sheets (however, between adjacent sheets,
Shiitake inoculum was inoculated in exactly the same manner except that the holes in one sheet did not overlap with the holes in the other sheet (invention 3). The culture medium was then maintained at a temperature of 23°C and humidity.
When cultured under conditions of 60 to 70%, the control sample was contaminated by harmful bacteria entering the atmosphere, and the culture could not be continued.

[Table] Example 2 A double bag with a diameter of 15 cm and a height of 20 cm was made by punching holes in the inner sheet in a grid pattern of 2 cm on a side and in the outer sheet in a vertical pattern at 5 cm intervals using a sewing loop. Beech sawdust 5 on high-speed film
A culture medium prepared by adding 0.5% of raw rice bran to 60% moisture was added to the culture medium, and sterilized by applying saturated steam at a pressure of 1 kg/cm ² and a temperature of 120°C for 90 minutes, and then cooled to room temperature. , Shiitake seed fungus (Kawamura Edible Bacteria Research Institute S54) was inoculated (the present invention). A culture medium containing 60% moisture was added to Hi-Zex film, which was made into a bag without punching holes with a looper, sterilized, cooled, and inoculated with shiitake mushroom starter (control). Next, the cells were cultured in a culture medium at a temperature of 23° C. and a humidity of 60 to 70% for 20 to 35 days. After the mycelium spread, the culture was continued for 50 to 180 days at a temperature of 20°C and a humidity of 70 to 80%, and primordium formation was observed on the surface layer of the culture medium, so the film was removed and the culture medium was transferred to the growth chamber. The above culture medium is kept at a temperature of 15-20℃ in the generation chamber.
The fruiting bodies were kept under conditions of 85 to 95% humidity for 7 days to develop fruiting bodies, and the fruiting bodies were harvested. For the second and subsequent harvests, the culture medium was submerged in water to allow fruiting bodies to develop.
Note that the yield is the total yield in three outbreaks.

[Table] From the above results, it can be seen that the present invention not only shortens the cultivation period but also increases the yield of fruiting bodies. Example 3 With a slit length of 1 cm, use a cutter to open the slits so that the distance between the slits is 1.5 cm (vertical) and 5 cm (horizontal), and align the slits so that the inner side in contact with the medium surface and the outer side in contact with the outside air surface do not overlap, and adjust the diameter.
Processed into double bags 15cm high and 20cm high, sterilized by adding 5 parts of beech sawdust and 0.5 parts of raw rice bran to a Hi-Zex film to give a moisture content of 60%, then cooled to room temperature and used as a shiitake mushroom starter. (Mori Sangyo Co., Ltd. W4) (this invention). A culture medium containing 60% water was added to Hi-Zex film, which was made into a bag without slits, sterilized, cooled, and shiitake mushroom seed was inoculated (control). The culture medium was then cultured for 25 to 35 days at a temperature of 23°C and a humidity of 60 to 70%. After mycelial spread, the culture was continued for 60 to 180 days at a temperature of 20° C. and a humidity of 70 to 80%, and primordium formation was observed on the surface layer of the culture medium, so the film was removed and the culture medium was transferred to the growth chamber. The above culture medium is heated in the generation room at a temperature of 15-20℃ and a humidity of 85-95℃.
% conditions for 7 days to develop fruiting bodies,
The fruiting bodies were harvested. For the second and subsequent harvests, the culture medium was submerged in water to allow fruiting bodies to develop. The yield is the total yield in three outbreaks.

[Table] From the above results, it can be seen that the present invention not only shortens the cultivation period but also increases the yield of fruiting bodies. Example 4 A high-speed film made into a double bag with a diameter of 15 cm and a height of 20 cm by punching holes in the inner sheet in a grid pattern of 4 cm on a side and in the outer sheet in a vertical pattern at 5 cm intervals using a sewing loop. beech sawdust 5
Add a culture medium prepared by adding 1 part of raw rice bran to 63% moisture and heat at a pressure of 1 kg/cm ^2.
After being sterilized by applying saturated steam at 120°C for 90 minutes, it was cooled to room temperature and inoculated with Nameko seed fungus (Kokuken Sangyo N217) (the present invention). A culture medium containing 63% moisture was added to a Hi-Zex film, which was made into a bag without punching holes with a looper, sterilized and cooled, and Nameko inoculum was inoculated (control). Next, the culture medium is cultured and matured at a temperature of 23°C and a humidity of 60-70%, after which the bag is removed and transferred to a fruiting body generation chamber, where the fruiting bodies are incubated at a temperature of 15°C and a humidity of 85-95% with occasional watering. generated an entity.

[Table] From the above results, it can be seen that the present invention not only shortens the cultivation time but also increases the yield of fruiting bodies.

Claims (1)

[Claims] 1. Consisting of two or more porous synthetic resin sheets,
A method for cultivating basidiomycetes, which comprises cultivating a nutrient substrate between adjacent sheets by covering the nutrient substrate with a packaging sheet in which the holes in one sheet do not substantially overlap with the holes in the other sheet. 2. The method for cultivating basidiomycetes according to claim 1, wherein the porous synthetic resin sheet is a porous synthetic resin sheet with a pore diameter of 1 mm or less. 3. The method for cultivating basidiomycetes according to claim 1, wherein the two or more porous synthetic resin sheets are two or more porous synthetic resin sheets stacked so as to be able to slide on each other.