JPH0622644A - Composition for artificial culture of mushroom - Google Patents

Abstract

PURPOSE:To provide the composition satisfying mushroom growing conditions, safe in view of food sanitation, using chitosan as an inexpensive alternative to sawdust getting hard to obtain, containing a composite made up of bean-curd refuse and chitosan. CONSTITUTION:A composition comprising (A) 100 pts.wt. of bean-curd refuse, (B) 8 pts.wt. of chitosan (deacetylation degree: 75%), (C) 8 pts.wt. of lactic acid, and (D) 484 pts.wt. of water is agitated for 5 min. using a blender. Then, 4.5 pts.wt. of sodium bicarbonate is added to the composition followed by agitation to adjust the pH value of the blend at 6.2, and the resulting blend is cast into a stainless steel vat and frozen at -20 deg.C and then lyophilized. The resultant blend is treated in acetic anhydride to prepare a porous composite, which is then made into granules, thus obtaining the objective composition having the above-mentioned advantages and useful as a solid medium for artificial culture of mushroom such as Fomes japonicus, Flammulina velutipes, or shiitake.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to the use of okara, which is a by-product after the production of tofu, and more particularly to a composition used as a solid medium for artificial cultivation of mushrooms.

[0002]

2. Description of the Related Art Okara has heretofore been obtained as a by-product in the production of tofu, and various treatment methods and uses thereof have been studied. Recently, a technique has been known in which fats and oils and soybean protein are added to okara, and a lump food is formed by an extruder. (Food processing technology, VOL.
10, No. 2, 1990).

However, a practical method of utilizing okara has not been established so far, and although it has been partially used as a food material or feed, it has not reached a fundamental solution for its effective utilization, and it is more Development of high value-added usage is desired. On the other hand, chitosan is a deacetylated version of chitin obtained from crab and shrimp shells, and has the second largest biomass amount after cellulose, so its application development is being actively pursued.

Artificial cultivation of mushrooms has already been carried out with shiitake mushrooms, maitake mushrooms, enoki mushrooms, ganoderma lucidum, etc.
The medium used for cultivation is a mixture of sawdust (mainly deciduous broad-leaved tree) and rice bran at a fixed ratio. However, with the depletion of forest resources worldwide and the increasing demand for timber, it is currently difficult to obtain large numbers of sawdust for mushroom cultivation. In addition, the price of sawdust is increasing year by year, which is one of the factors that put pressure on the management of growers. Therefore, there is a demand for the development of a sawdust substitute that is inexpensive and available in large quantities.

To date, as an example of using chitosan for mushroom culture, a method of cultivating an edible mushroom by mixing sawdust and rice bran and adding an amino acid salt of chitosan as a water retention agent (JP-A-62-285729). ), A method of artificially cultivating by adding chitinase to a medium for culturing hyphae of basidiomycetes (JP-A-63-188323), a method of cultivating edible mushrooms by adding carboxymethyl cellulose and chitosan to the culture medium (special (Kaisho No. 62-232314), a fruiting body formation inducer of mushrooms containing N-acetylglucosamine or chitin oligomer as an active ingredient (JP-A-1-254606), and a mushroom containing chitosan oligomer or a salt thereof as an active ingredient. There are already fruiting body formation inducers (JP-A 1-211508) and the like, but none of them has been developed as a complete substitute for sawdust-rice bran.

[0006]

[Means for Solving the Problems] The present inventor has focused on utilizing okara for the purpose of developing a substitute of sawdust-rice bran medium for artificial cultivation of mushrooms. Then, in the process of considering the effective use of Okara, the complex of Okara and chitosan has an organized physical property having adhesiveness,
It was found that the medium has physical properties as a solid medium for artificial cultivation of mushrooms, and the present invention has been completed based on this finding.

The complex of okara and chitosan used in the present invention is produced by the following method. Chitosan is added to Okara, mixed under acidic conditions, neutralized, and lyophilized or extruded to obtain a viscous and structured product. The amount of chitosan to 100 parts of okara is 0.1 to 10 parts by weight, preferably 4 to
Eight copies. If it is less than 0.1 parts by weight, the okara will not bind,
In addition, it is not preferable because the growth of various bacteria cannot be suppressed sufficiently, and when it exceeds 10 parts by weight, the growth of mushroom fungi is affected. As the desirable acid, lactic acid, hydrochloric acid, sulfuric acid, citric acid, glutamic acid, acetic acid and the like which are commonly used in food production are used. Addition amount is 0.5 to 1 part chitosan
Three copies is appropriate. Adjust the pH to 6.0 or lower using these acids. If the pH exceeds 6.0, chitosan cannot be sufficiently dissolved, and a structured product in which okara and chitosan are sufficiently bound cannot be obtained. Next, neutralization is performed. Examples of the neutralizing agent include sodium carbonate, sodium bicarbonate, ammonium hydrogen carbonate, sodium hydroxide and the like. The pH after neutralization is
The range is 5.5 to 8, preferably 6 to 7.

After the neutralization step, organization is performed by freeze-drying or an extruder treatment. In the case of freeze-drying, it is frozen by leaving it in a freezing room at about -20 ° C. If it is frozen rapidly using liquid nitrogen etc., the ice crystals will become fine and fine texture will be obtained. Then freeze-dry. When acetic anhydride is added to the lyophilized product to acetylate chitosan, the chitosan becomes chitin and becomes water-insoluble, so that the water resistance and antibacterial property can be changed. The degree of acetylation is controlled by the amount of acetic anhydride used, the pH of the reaction solution, and the reaction time. Finally, it is neutralized with alkali, and the sample is thoroughly washed with water and dried.

When an extruder is used, it is 50-18
By heating at 0 ° C., preferably about 70 to 110 ° C., it is possible to continuously obtain a structured product having sufficient strength. The diameter of the small holes to be extruded is preferably 0.5 to 30 mm. If it is 0.5 mm or less, clogging tends to occur, and if it is 30 mm or more, it becomes difficult to supply the structured material. The structured product thus obtained is noodle-like and can be washed with water. It can also be dried with a drum dryer or the like and stored for a long period of time.

Both the freeze-dried product and the extruder-treated product are porous composites, which may be used after being crushed into granules having an appropriate size. The complex thus obtained is porous, good air circulation, and because chitosan has antibacterial activity, it prevents the growth of bacteria, so that it is used as a solid medium for artificial cultivation of mushrooms. Suitable to use. When this composite is used as a composition, it can be used as a substitute for sawdust-rice bran or as a partial substitute thereof. The mushrooms cultivated by the composition of the present invention are not particularly limited, and all of them can be applied to the mushrooms normally cultivated using sawdust-rice bran as a medium.

[0011]

EXAMPLES The present invention will be described in more detail with reference to the following examples. Production Example 1 Production of Complex of Okara and Chitosan Using Dry Freezing Method 100 parts by weight of Okara (water content 81.1%, oil 3.6%, protein 4.8
%, Sugar 6.4%, fiber 3.3%, ash 0.8%) and chitosan (deacetylation degree 75%) 8 parts by weight, lactic acid 8 parts by weight, water 4
84 parts by weight was added, and the mixture was stirred with a blender for 5 minutes. The pH at this time was 3.6. Next, 4.5 parts by weight of baking soda was added, and the mixture was further stirred for 5 minutes. At this time, the pH was 6.2 and it showed fluidity. The obtained mixture was poured into a stainless steel vat, frozen at −20 ° C., and then freeze-dried. It was then treated in acetic anhydride to prepare a porous composite and granulate it.

Production Example 2 Production of Complex of Okara and Chitosan Using Extruder 100 parts by weight of Okara (water: 79.6%, protein: 5.2%, lipid: 4.
5% by weight of chitosan was added to 2%, sugar 6.7%, crude fiber 3.4%, and ash 0.9%), and mixed for 2 minutes in a kettle emulsifying kettle. Next, 8 parts by weight of lactic acid was added and mixed for 3 minutes. The pH at this time was around 4. Then 4.5 parts by weight of baking soda was added and further mixed. The pH at this time was about 6.5. This mixture is put in an extruder at a rotation speed of 130 rpm, the first barrel temperature is 100 ° C, the second barrel temperature is 130 ° C, and the die diameter is 1.5 mm.
A noodle-like chitosan-okara porous composite was prepared under the conditions of × 2, feed rate of about 33.6 kg / hour, and pressure of about 50 kg / cm ² .

Example 1 Ganoderma lucidum and rice bran were mixed at a weight ratio of 4: 1 and water was added to prepare a water content of 63% by weight (1.7 to water for 1 medium). A predetermined amount was packed in a pot, and a hole having a diameter of 1.5 cm and a depth of 5 cm was formed in the center, and sterilized at 121 ° C. for 120 minutes.
Similarly, only the chitosan-okara complex prepared in Production Example 1, a mixture of sawdust and the chitosan-okara complex prepared in Production Example 1 in a weight ratio of 4: 1, and rice bran and Preparation Example 1 were prepared. The mixture of the above chitosan-okara complex at a weight ratio of 1: 4 was adjusted to have a water content of 63% by weight. The pot was filled in the same manner as above and sterilized at 121 ° C. for 20 minutes.

After sterilization, each medium was sufficiently cooled to room temperature,
An inoculum of Ganoderma lucidum grown on potato dextrose agar was inoculated. Incubate at 25 ° C and 50% relative humidity for 20-30 days. After the hyphae grow on the entire surface of the pot, remove the lid,
Put it in a container that is deep enough to contain the entire pot, and then fill the container with a bowl of red ball soil that has been sufficiently absorbed and sterilized.
The cells were cultured at 30 ° C., 95% relative humidity and 140 lux for 14 days.
When the fruit body primordia were formed and extended, the illuminance was raised to 600 lux and the cells were cultured at 30 ° C and 70% relative humidity. The results are shown in Table 1.

[0015]

[Table 1]

Example 2 Enokitake sawdust and rice bran were mixed in a weight ratio of 3: 1 and water was added to adjust the water content to 63% by weight. 12 pieces with a hole of 1.5 cm in diameter and 5 cm in depth in the center
Sterilized at 1 ° C for 120 minutes.

Similarly, only the chitosan-okara complex prepared in Production Example 2, a mixture of sawdust and the chitosan-okara complex prepared in Production Example 2 in a weight ratio of 3: 1, rice bran and Production Example. A mixture of the chitosan-okara complex prepared in 2 in a weight ratio of 1: 3 was adjusted to a water content of 65%. Fill the pot as above
Sterilized at 121 ° C for 20 minutes. After sterilization, each medium was sufficiently cooled and inoculated with Enokitake inoculum grown on potato dextrose agar. After culturing at 18 ° C. and 75% relative humidity for 20 days, the fungus was scratched. Then, it was cultivated at 13 ° C. and 95% for 10 days to form fruit bodies, and further cultivated at 3 ° C. and 75% for 15 days in a suppression chamber, and then cultivated at 5 ° C. and 70% for 10 days and harvested.
The results are shown in Table 2.

[0018]

[Table 2]

Example 3 Shiitake sawdust and rice bran were mixed in a weight ratio of 10: 1.5, and water was added to adjust the water content to 65%. A predetermined amount was packed in a cultivation bag, a hole having a diameter of 1.5 cm was made at several places, and sterilized at 121 ° C for 120 minutes. Similarly, only the chitosan-okara complex prepared in Preparation Example 1, a mixture of sawdust and the chitosan-okara complex prepared in Preparation Example 1 in a weight ratio of 10: 1.5, and rice bran and Preparation Example 1 were prepared. A mixture of chitosan-okara complex at a weight ratio of 1.5: 10 was adjusted to a water content of 65%. The cultivation bag was packed in the same manner as above, punctured, and sterilized at 121 ° C. for 20 minutes.

After the sterilization, the medium was sufficiently cooled and inoculated with the shiitake inoculum grown on the potato dextrose agar medium. After 100 days of culturing at 22 ° C and 75% relative humidity, germination shock was applied. After forming the fruit body primordium, smash the bag and
After culturing at 95 ° C for 7 days at 95%, fruiting bodies were formed. The results are shown in Table 3.

[0021]

[Table 3]

As described above, according to each of the examples, when the complex comprising okara and chitosan is used alone or in combination with sawdust in the medium for artificial cultivation of mushrooms, the conventional sawdust-
It was found that the average yield did not change much as compared with the case of using the rice bran medium, and it could be sufficiently used as a substitute.

[0023]

INDUSTRIAL APPLICABILITY According to the present invention, by effectively utilizing a complex consisting of okara and chitosan, which are by-products of tofu, it is possible to provide a safe medium for artificial cultivation of mushrooms, which is provided with conditions for growing mushrooms and is safe for food. A composition can be provided which can be used. This composition can be used as an alternative to the conventional sawdust-rice bran medium.

Claims (1)

[Claims] 1. A composition for artificial cultivation of mushrooms, which contains a complex of okara and chitosan.