JPH0475730B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a mature artificial shiitake mushroom tree capable of producing a large amount of high quality shiitake mushrooms. [Conventional technology] In general, Shiitake mushroom cultivation involves inoculating seed fungi into Shiitake logs, covering them with grass, como, etc. to prevent direct contact with the outside air, and promoting the growth of mycelium in this state (temporarily laying down). This is done by spreading the fungus to create a staghorn tree, and then spreading this staghorn tree in an appropriate location to cause mycelium to grow and become mushrooms. However, with this conventional method of cultivating shiitake mushrooms,
Due to the decrease in shiitake logs, it is becoming difficult to supply them, and since the cultivation period is long, there is a desire to shorten the cultivation period. For this reason, recently
It is being considered to produce artificial mulberry trees using sawdust and the like, and to use these to cultivate shiitake mushrooms. In this artificial cultivation of shiitake mushrooms, a bottle is filled with sawdust to serve as a fungus bed medium, and the original bacteria are inoculated into the bottle, which is then capped and cultured to produce a white, soft mycelial mass (a fungal bed in which mycelium spreads). Alternatively, there is a method in which the mycelial mass is further overcultured to make the surface of the mycelial mass bulge-like, and the resulting mycelial mass is removed from the bottle and given a low-temperature shock by immersing it in cold water at appropriate times to cause the mushrooms to sprout. [Problems to be solved by the invention] However, according to the above method, it is easy to be contaminated with harmful bacteria, oddly shaped mushrooms occur, the growth rate of cut buds is poor, the growth rate is uneven, and the quality is poor. Also, there is a drawback that the yield is unstable. That is, in the above method, the state in which white mycelia have spread inside the bottle is determined with the naked eye, and when the inside of the bottle is filled with white mycelia and the surface of the mycelial mass has a raised state, the mycelial mass is taken out and removed. It is used as an artificial tree for cultivating shiitake mushrooms. However, when cultivating shiitake mushrooms using such artificial trees, the maturity of the mycelial mass, that is, the artificial tree, can be determined with the naked eye using the white color of the mycelial mass, the raised state of the surface of the mycelial mass, etc. Because this process is carried out using a method called ``Maturity'', the maturity level is inaccurate, and the seeds are cultivated while still being insufficiently mature. For this reason, there is a problem that many artificial saplings are produced due to poor bud pruning and poor quality and yield. The present invention was made in view of the above circumstances, and its purpose is to provide a fully-ripened artificial tree that can produce shiitake mushrooms with stable yield and quality of fruiting bodies over the entire cultivation period. [Means for Solving the Problems] In order to achieve the above object, the artificial shiitake mushroom tree of the present invention is an artificial shiitake mushroom tree containing cellulose and lignin derived from a culture medium. The weight ratio is set to 3.3 or higher. [Effect] In other words, the present inventors found that there is a gap between the whiteness and raised state of the mycelial mass due to the spread of mycelia, which are used as a guideline for determining the degree of ripeness of artificial mulberry trees, and the actual degree of ripeness. I conducted a series of studies thinking that this might be the case. As a result, even if the hyphae are sufficiently spread and the hyphae mass (artificial tree) turns white, the hyphae mass is not fully ripened in reality, and there is a difference between the state based on the spread of hyphae and the actual fully ripe state. It was found that there was a considerable gap in the mycelial mass, and when the mycelial mass turned white or became bulged, it was not yet fully ripe. Therefore, in order to objectively judge the degree of ripeness, Shiitake fungi assimilate (digest) cellulose and lignin in the medium during growth, and the amount of cellulose assimilated and the amount of lignin assimilated during mycelial growth. They found that there was a correlation between the amount of oxidation and a series of further studies. As a result, (cellulose)/(lignin)
The weight ratio (hereinafter referred to as "ratio") is suitable as an indicator of ripeness, and if the ratio is 3.3 or higher,
It was discovered that the artificial mulberry tree was actually fully ripe,
We have arrived at this invention. That is, when the (cellulose)/(lignin) ratio is 3.3 or more, the medium component raw materials are sufficiently digested and the mycelium mass is in a mature state. The lignin decomposition products necessary for forming the shiitake fruiting body are sufficiently absorbed into the mycelium mass. Therefore, when cultivating shiitake mushrooms using such fully-ripened artificial trees, it is possible to produce high-yield and high-quality shiitake mushrooms over the entire cultivation period. In addition, the appearance of the above-mentioned fully ripened artificial staghorn is not white but brownish in appearance. Next, this invention will be explained in detail. The fully ripened artificial shiitake mushroom tree of this invention is, for example,
It can be manufactured as follows. That is, first, a solid medium is prepared using sawdust, rice bran, bran, etc. as a medium composition, and this solid medium is filled into a container such as a polypropylene bottle or bag and sterilized by heating. Next, the inoculum was inoculated and the mycelium was cultured for 1 to 2 months at the optimal temperature for mycelial culture (20 to 26°C).
After the mycelial mass becomes a grown mycelial mass with a slightly raised surface, it is removed from the container. Conventionally, this has been provided as is as an artificial tree, but in this invention, the mycelium taken out from the container is arranged on a net-like shelf at a predetermined interval, and the mycelium of the mycelium is grown in this state. During this mycelium growth process, for example, as shown in FIG. Water for a month. In this case, watering should be divided into two stages: first, watering continuously to promote the activation of mycelium, and then watering slowly (watering with a small amount of water to avoid excessive moisture remaining in the mycelial mass) , watering for several hours a day) will give good results. The fully ripe shiitake mushrooms obtained in this way have a (cellulose)/(lignin) ratio of 3.3 or more. When producing this fully ripened artificial shiitake mushroom tree, the (cellulose)/(lignin) ratio was investigated when the mycelial mass was removed from the container and 20 days after it was placed on a shelf and watering started, and the results are shown in Figure 2.
In addition, in the initial medium raw material wood flour, (cellulose)/
The (lignin) ratio is usually in the range of 1.5 to 2.0, and this value varies depending on the amount of rice bran added and the wood used as the raw material for the wood flour. For example, if the amount of rice bran is small, the cellulose content will be low, so the (cellulose)/(lignin) ratio will be close to 1.5. and,
When taken out of the container, the (cellulose)/(lignin) ratio was 2.5, indicating that it was not fully ripe. And for this,
By watering for 20 days and continuing culturing, the (cellulose)/(lignin) ratio reaches 3.3, reaching full ripeness. The preferred range of the above (cellulose)/(lignin) ratio is 3.5 to 5.5. In this way (cellulose) / (lignin)
When setting the ratio of 3.3 or higher, (cellulose)/
(lignin) and lignin content (solid amount)
It is suitable that the amount is 15% by weight (hereinafter abbreviated as "%") or less, preferably 9 to 13%. In other words, when the lignin content (solid amount) decreases compared to the content in the initial mycelial mass, it means that the lignin is decomposed and the assimilation (digestion) rate of the medium is increasing. By reducing the lignin content to 15% or less in combination with the cellulose/lignin ratio, it becomes possible to more accurately determine the degree of maturity of the mycelial mass. Note that the above-mentioned cellulose and lignin were quantified by an analysis method based on the JIS method. The artificial shiitake mushroom logs obtained as described above can be treated in the same manner as shiitake logs derived from general shiitake logs by sprinkling with water or soaking in water to absorb water using known low-temperature stimulation, etc., to generate shiitake mushrooms. It is something. In this case, the yield is stable and high during the entire cultivation period, and there is no variation in quality. [Effects of the Invention] As described above, the fully ripened artificial shiitake mushroom tree of this invention can be used to determine the degree of ripeness using the spread of mycelium (when it spreads, the appearance becomes white) and the increase in ridges on the surface, unlike conventional methods. Ripeness is determined based on the (cellulose)/(lignin) ratio, which more accurately represents the actual ripeness, and is 3.3 or higher (3.3 or higher is ripe). . Therefore, over the entire cultivation period, shiitake mushrooms of stable quality can be produced at a high rate without causing poor bud pruning or uneven fruiting body growth due to lack of vigor of the bamboo shoots. Next, examples of the present invention will be described together with comparative examples. [Example, Comparative Example] (Culture of mycelial mass) First, mycelial mass was cultured as follows. That is, sawdust, rice bran, and bran were mixed in a ratio of 8:1:1, and water was added to this. 1 kg of this medium was filled into a container made of polypropylene, and a cap with a filter was attached. This was heated at 121°C.
Sterilize at high temperature for 90 minutes and inoculate with shiitake seed fungi.
The mycelia were cultured at a temperature of 0.degree. C. as shown in Table 1 to obtain mycelial masses. (Watering) Next, the mycelial mass was watered continuously for the number of days shown in Table 1 below as shown in Figure 1, and then
Gentle watering (watering for 8 hours a day) was performed for the number of days shown in the same table to obtain artificial mulberry trees. The (cellulose)/(lignin) ratio of the artificial Japanese oak thus obtained was determined and shown in Table 1 below. In this case, the amounts of cellulose and lignin were quantified by an analysis method based on the JIS method. At this time, the number of specimens was n=30 for each. (Cultivation method) Next, the artificial mulberry trees of Examples and Comparative Examples obtained in this way were cultivated for 6 months at a temperature of 8 to 18°C, and the bacterial contamination rate of the mulberry trees and the yield of Shiitake mushrooms were evaluated. The average weight per shiitake mushroom and the appearance rate of modified fruit bodies were investigated and shown in Table 1 below. In addition,
The yield of shiitake mushrooms was determined by dividing the total amount of shiitake mushrooms produced by the total weight of the initial culture medium.

【table】

[Table] From the results in Table 1, in Examples 1 to 4, the mycelial mass was matured under suitable watering conditions and temperature conditions, so that lignin was fully utilized. In particular, in Examples 3 and 4, the decomposition (assimilation) rate of lignin was high, so (cellulose)/
(lignin) ratio is 4.5 or more and lignin content is 10% or less. Comparing Example 3 and Example 4, there is almost no difference in the yield of Shiitake mushrooms between the two, but the weight of Shiitake mushrooms in Example 4 is higher than that in Example 4.
less than. This is thought to be because the lignin content of the artificial Japanese oak of Example 4 was less than 9%, and this was the difference from Example 3. On the other hand, in Comparative Examples 1 to 3, lignin was not fully utilized because the culture conditions, watering conditions, and temperature conditions were inappropriate. For this reason, activation of mycelia and full ripening of artificial mulberry trees are not achieved, and contamination with harmful bacteria and deformation of fruiting bodies are likely to occur, resulting in a decrease in yield and quality.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of watering a mycelial mass taken out from a container in an embodiment of the present invention, and FIG. 2 is an illustration of (cellulose)/(lignin)
It is an explanatory diagram of a change state of a ratio. 1... Mycelia mass, 2... Shelf, 3... Watering device or watering nozzle.

Claims (1)

[Claims] 1. A fully ripened artificial shiitake mushroom tree containing cellulose and lignin derived from a culture medium, which is characterized in that the weight ratio of (cellulose)/(lignin) is set to 3.3 or more.