JPH043169B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a method for producing a mushroom culture medium inoculated with inoculum used for cultivating mushrooms such as shiitake and oyster mushrooms. [Prior Art] Mushrooms such as shiitake and oyster mushrooms are relatively easy to cultivate, so large-scale cultivation is now being carried out by farmers. Until now, the mainstream method of artificially cultivating mushrooms was to use logs and inoculate them with inoculum to cause mushrooms to grow.However, with the depletion of logs, it has become more common to use culture media mainly made of sawdust. The method is now being replaced by inoculating the mushrooms with inoculum and causing the mushrooms to sprout. This is typically done in the following way. That is, first, a culture medium material consisting mainly of sawdust is prepared, this is packed in a container and sterilized by heating, etc., and then the obtained culture medium is inoculated with seed bacteria to form an artificial culture medium for mushrooms. Mushrooms such as shiitake and oyster mushrooms are produced by culturing this to spread mycelia and then causing the mushrooms to sprout. In the above-mentioned artificial cultivation, there are two types of seed bacteria used: solid seed bacteria and liquid seed bacteria. The above-mentioned solid inoculum is obtained by inoculating the inoculum into a solid culture medium mainly composed of rice bran, sawdust, etc., allowing hyphae to spread therein, and then pulverizing the inoculum, and is solid. On the other hand, a liquid starter is obtained by inoculating a starter into a liquid culture medium such as a potato culture solution, and is a liquid. [Problems to be Solved by the Invention] However, regardless of whether the above-mentioned solid seed or liquid seed is used, both have the following drawbacks, and therefore it is difficult to scale up the artificial cultivation of mushrooms. Have difficulty. In other words, in the case of artificially cultivating mushrooms using a solid seed, the formation of the solid seed and the inoculation must be performed in small quantities, and the equipment that is to be used repeatedly must be sterilized each time, which is complicated. The first difficulty is that the Moreover, in this case, the second difficulty is that the culture period is long and inconsistent. On the other hand, when artificially cultivating mushrooms using a liquid seed, inoculation is carried out by spraying the liquid seed onto the surface of the culture medium, which often results in excessive moisture locally during the spraying, which causes the elongation of hyphae. is likely to be suppressed. In addition, since water tends to volatilize from the surface of the culture medium, the seed culture environment becomes deficient in water over time, causing the proliferation of harmful bacteria. For this reason, the reality is that liquid seed bacteria are hardly used. On the other hand, an inoculum prepared by mixing mushroom hyphae with an aqueous solution of a binder of a water-soluble synthetic polymer substance selected from cellulose derivatives, polyvinyl alcohol, and propylene glycol alginate to form a paste has been proposed (Tokuko Sho). No. 47-51059). This paste-like starter is prepared for the purpose of inoculating the logs mentioned above, and the starter is inoculated by drilling small holes in the log and coating the paste-like starter into the holes. ing. In this case, since the seed fungus is pasty and sticky,
It has good inoculation workability without running off, and a film of synthetic polymer material based on the seed paste is formed on the surface of the inoculation site, which protects the seed and increases its ability to take root. . However, when this is applied to a shiitake mushroom culture medium using a culture substrate mainly composed of sawdust, there are difficulties in terms of injection into the culture medium, inoculation efficiency, and handling. The present invention was made in view of the above circumstances, and its purpose is to provide a method for producing a mushroom culture medium in which the inoculum is inoculated to the inside, which has a high inoculation efficiency, and which can also be automated. shall be. [Means for Solving the Problems] In order to achieve the above object, the method for producing a mushroom culture medium inoculated with inoculum of the present invention involves preparing a solid mushroom culture medium using a granular or powdered medium material, sterilizing the medium, and then sterilizing it. , a method in which a small-diameter nozzle is inserted into this sterilized mushroom culture medium, and an inoculum is inoculated through this small-diameter nozzle, and the inoculum is mushroom mycelia selected from agar, carrageenan, modified starch, and xanthan gum. Using a paste seed with a viscosity of 2,000 to 30,000 cps, which is prepared by mixing an aqueous solution of a water-soluble polymer binder, the tip of the above-mentioned small-diameter nozzle should be placed at a depth of 1/2 L to L, where L is the thickness of the mushroom culture medium. Plug directly into
Next, the pasty starter is injected under pressure while being gradually pulled up, and the pasty starter is inoculated in a vertically extending line. [Function] The present inventors believe that the paste-like starter is easier to handle than solid starters or liquid starters, and therefore,
Focusing on the possibility of mass-producing mushroom culture media, we conducted a series of studies to solve the above-mentioned problems with the above-mentioned paste-like inoculum. As a result, we came up with the idea that it would be preferable to use a small diameter nozzle to inoculate mushroom culture media made of granular or powdered medium materials such as sawdust instead of logs, and based on this, we conducted a series of further studies. layered. As a result, we made an aqueous solution using agar, carrageenan, modified starch, xanthan gum, etc. as the binder component, mixed mushroom mycelia into this aqueous solution, and adjusted the overall viscosity to 2,000 to 30,000 cps. It has been found that it can be smoothly injected into mushroom culture medium.
Furthermore, if the thickness of the culture medium is L, insert the small diameter nozzle to a depth of 1/2L to L,
While injecting the pasty starter under pressure, the small-diameter nozzle is gradually raised to inoculate the pasty starter in a vertically extending line, and the linearly inoculated starter spreads around the outer periphery around the linear inoculation area. The seedlings grow in the same direction, forming a uniform inoculated area deep inside the culture medium. As a result, the inventors discovered that it is possible to shorten and stabilize the cultivation period in artificial cultivation of mushrooms, and have arrived at this invention. Next, this invention will be explained in detail. The paste starter used in this invention can be obtained, for example, as follows. That is, it can be obtained by adding and mixing a previously sterilized water-soluble polymeric material binder (hereinafter abbreviated as "binder") to a solid seed culture or a liquid seed culture obtained by a conventional method. The method of mixing the above-mentioned binders is usually not to add and mix the binders as they are.
The binder is dissolved in distilled water to form a binder adjustment liquid, and then added and mixed. As the above-mentioned binder, one that has heat sterilization resistance and mushroom enzyme resistance, and does not inhibit the growth of mushroom hyphae is suitably used. As such a binder, agar, carrageenan, modified starch, and xanthan gum are used alone or in combination. Such a binder has good affinity for the mushroom culture medium made of granular or powdered medium materials such as sawdust, so that when the paste-form starter is injected, the paste-form starter becomes well inside the mushroom culture medium. It grows and forms an inoculum area. In addition, in order to examine the adaptability of each of the above-mentioned binders to the paste starter, each item shown in Table 1 below was evaluated. In this case, each binder was a distilled aqueous solution having a concentration shown in Table 1.

〔Effect of the invention〕

As described above, the present invention provides a paste-form inoculum with a viscosity of 2,000 to 30,000 cps, which is obtained by mixing mushroom mycelium with an aqueous solution of a water-soluble polymer binder selected from agar, carrageenan, modified starch, and xanthan gum. Using this, insert the tip of the small diameter nozzle into the mushroom culture medium, and if the thickness of the culture medium is L, then 1/2L
A depth of ˜L is reached, and the paste starter is injected under pressure from the tip of the nozzle while being gradually pulled up, and the paste starter is inoculated in a vertically extending line. Therefore, inoculation of the inoculum into an artificial culture medium for mushrooms using sawdust or the like can be carried out particularly well. In other words, the paste-like starter is adjusted to the above-mentioned viscosity, and at the same time, the water-soluble polymer binder constituting the paste-like starter is selected as a specific binder. It becomes well adapted to the culture medium, and can also be smoothly injected using a small diameter nozzle. In this case, if the thickness of the culture medium is L, the nozzle is
By inserting the paste to a depth of 1/2L to 1/2L and inoculating the paste starter in a linear manner while gradually pulling it up, the paste starter can be inoculated deep into the mushroom culture medium. After injection, the inoculated paste-like inoculum grows and spreads in the outer circumferential direction centering on the linear inoculated part, so that the inoculated area is uniformly formed deep inside the mushroom culture medium, and the hyphae grow and spread. It will be possible to shorten the time it takes to spread the virus. As described above, the inoculum inoculated culture medium of the present invention has an inoculated area uniformly formed deep inside, so that the mycelium spreads uniformly throughout the whole, resulting in shortening the mushroom cultivation period and increasing the yield. It becomes possible to realize it. In addition, by performing injection using the above-mentioned small-diameter nozzle, it becomes possible to inject the inoculum at the same time as making the hole, thereby making it possible to automate the inoculation. Therefore, it will be possible to modernize and rationalize the operation of artificial culture medium for mushrooms. Furthermore, according to such inoculation, the inoculum can be inoculated uniformly over the entire culture medium without wasting it, and the amount of inoculum to be inoculated can be significantly reduced. Next, examples will be described together with comparative examples. <Preparation of Paste Inoculum A> Add agar to distilled water and heat and dissolve for 10 minutes to prepare a 1% by weight (hereinafter abbreviated as "%") agar aqueous solution, then heat steam at 121°C for 20 minutes. Sterilized and homogenized by stirring. On the other hand, a bacterial mass was scraped out from a solid shiitake seed culture bottle in which the mycelium had been spread by the usual culture method, and the wet weight of this bacterial mass was
A paste starter a (viscosity 7000 cps) was prepared by mixing 4 g of the above agar solution with 12 ml of the above agar aqueous solution. Example 1 First, sawdust and rice bran were mixed at a ratio of 5:1,
The medium was adjusted to have a moisture content of 70% by adding water. Then, 1 kg of this was filled into a polypropylene bag and formed into a circular shape with a diameter of 110 mm and a height of 120 mm.The upper end was bent and the bag was sterilized with steam at 121°C for 90 minutes. This sterilized culture medium was opened, and the above paste-like inoculum was injected into the medium using a nozzle with a diameter of 20 mm so as to form a linear shape of 20 mm x 100 mm in diameter. The injection was performed at one location as shown in FIG. After injection, a previously sterilized lid was attached to the opening of the medium and cultured in an atmosphere at 25°C. Comparative Example 1 A cylindrical hole was made in the culture medium using a rod, and 8 g of wet weight of granular inoculum obtained by a conventional method was dropped from the top to inoculate the culture medium. Other than that, Shiitake mushrooms were cultured in the same manner as in Example 1. The average number of days required to complete mycelial infestation in the above examples and comparative examples, and the yield after removing the polypropylene bags and cultivating for 10 months to form fruiting bodies were investigated. The results are shown in Table 2. In Table 2, the samples for each item are
There are 30 pieces.

[Table] From the results in Table 2, the average number of days for mycelia to spread in Example 1 was significantly shortened compared to Comparative Example 1, and the relationship between fruiting body and fruiting body mass showed that fruiting bodies of good shape and uniform amount were produced. You can see what you can get. <Preparation of Paste Inoculum B> Add carrageenan to distilled water and heat and dissolve for 10 minutes to prepare a 2% carrageenan aqueous solution, then heat steam sterilize at 121°C for 20 minutes,
Stir to homogenize. On the other hand, a bacterial mass was obtained from a solid oyster mushroom seed culture bottle in which the mycelial infestation had been completed using the usual method.
By scraping out 4g (wet weight) and mixing it with 12ml of the above carrageenan aqueous solution, a paste-like starter b.
(viscosity 10,000 cps) was prepared. Example 2 The above b was used as a paste starter. Other than that, Oyster mushrooms were cultured in the same manner as in Example 1. Comparative Example 2 In place of the Shiitake fungus in Comparative Example 1, Oyster mushroom fungus was used. Other than that, an artificial culture medium was prepared in the same manner as in Comparative Example 1, and cultured at 25°C. The amount of inoculated bacteria and the number of days required to complete the spread of mycelia in the above Examples and Comparative Examples, and after scraping the upper part of the bacteria, cultivation under conditions of 8 to 10℃, under artificial light, and humidity of 95% or more The yield of the fruiting bodies produced by this process was investigated and shown in Table 3 below. In addition, in Table 3, the number of specimens is 30 each.

[Table] As is clear from Table 3, in Example 2, the number of days for mycelial spread was significantly shorter than in Comparative Example 2, and the amount of fruiting bodies per culture medium was large, yielding good results. I understand that. <Preparation of liquid shiitake mushroom starter> 500g of corn starch, 100g of glucose, corn stave liquor (C.
Add 130g of SL) and mix the liquid medium at 121℃ for 60 minutes.
Autoclave sterilized for minutes. On the other hand, 100 ml of sterile water was added to 50 g of sawdust shiitake seed fungi prepared in advance, homogenized, and added to the liquid medium. This at 25℃
Below, a liquid shiitake seed fungus was prepared by stirring culture for one week. <Preparation of Paste Inoculum C> Modified starch was added to distilled water and dissolved by heating for 10 minutes to prepare a 10% starch aqueous solution, followed by heat steam sterilization at 121° C. for 20 minutes and homogenization by stirring. 1 volume of the above liquid inoculum per 1 volume of this starch aqueous solution
Add the volume and mix to make a paste starter c (viscosity
12000cps) was prepared. Example 3 The pasty starter c was automatically injected into the culture medium using the inoculation device shown in FIG. That is, this inoculation device 7 includes a culture tank 8 for the liquid shiitake seed, and a pump 9 from the culture tank 8.
A pasty seed preparation tank 10 adds and stirs and mixes a binder preparation liquid (in this case, a starch aqueous solution) to the liquid seed provided through the liquid seed preparation tank 10, and a pump 11 and a solenoid valve 12 from this paste seed preparation tank 10.
and a nozzle 13 for injecting the paste-like seed culture supplied through the medium 2 into the medium 2. The nozzle 13 is reciprocated in the vertical direction by a driving means (not shown) such as a cylinder, and the nozzle opening can be inserted into the culture medium to a predetermined depth. Therefore, by placing the sterilized culture medium 2 with an opening below the nozzle 13 of this device 7 and lowering the nozzle 13, the nozzle opening can be inserted into the medium, and the paste-like inoculum can be inserted from the nozzle opening. By raising the nozzle 13 while discharging, linear injection of the paste starter is automatically performed. Shiitake mushrooms were cultured in the same manner as in Example 1, except that such an inoculation device 7 was used. In this example, the amount of inoculated bacteria, the number of days required to complete the spread of mycelia, and the yield of fruiting bodies produced by cultivating for 10 months after removing the polypropylene bag were investigated and are shown in Table 4 below. In addition, in Table 4, the number of specimens is 30.

【table】 [Brief explanation of drawings]

FIGS. 1 and 2 are explanatory diagrams for explaining the injection of the paste-like inoculum of the present invention into a culture medium, FIG. 3 is a front view showing a modification of the nozzle used for the injection, and FIG. 4 is an explanatory diagram of the present invention. An explanatory diagram for explaining an inoculation device used for injecting a paste-like starter into a culture medium,
FIG. 5 and FIG. 6 are explanatory diagrams for explaining other inoculation modes of the paste-like starter of the present invention, respectively. 1... Nozzle, 2... Culture medium, 4... Pasty starter.

Claims (1)

[Claims] 1. A method in which a solid mushroom culture medium is prepared using granular or powdered medium material, and after sterilization, a small-diameter nozzle is inserted into the sterilized mushroom culture medium, and the inoculum is inoculated through the small-diameter nozzle. , Mushroom mycelia were used as the above-mentioned inoculum, agar, carrageenan,
A viscosity of 2000~ made by mixing with an aqueous solution of a water-soluble polymer binder selected from modified starch and xanthan gum.
Using 30,000 cps of paste-like inoculum, the tip of the above-mentioned small-diameter nozzle is 1/
A method for producing a mushroom culture medium inoculated with inoculum, which is characterized by directly inserting the inoculum into a depth of 2 L to L, and then gradually pulling it up while injecting a paste inoculum under pressure, and inoculating the paste inoculum in a vertically extending line.