Mycelium structure and method for producing mycelium structure

Abstract

Provided is a mycelium structure having excellent mechanical strength and flexibility. Also provided is a method for producing a mycelium structure having excellent mechanical strength and flexibility. A mycelium structure according to the present invention has: a mycelium comprising mycelia connected in a three-dimensional shape; and a starchy substance covering the mycelia. In addition, the density of the mycelium structure is preferably 0.8 g / cm3 or more and 5.0 g / cm3 or less. In addition, the average diameter of the hyphae covered with starch is preferably 2.0 [mu] m or more and 20.0 [mu] m or less. Furthermore, in a stress-strain curve showing the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, the maximum stress in the elastic region is preferably 2.0-40.0 MPa inclusive, and the maximum strain is preferably 0.5-4.0% inclusive.

Description

Technical Field

[0001] This invention relates to a mycelial structure and a method for manufacturing the mycelial structure. Background Technology

[0002] In recent years, as products with low environmental impact, the market has demanded products made from natural materials. For example, Patent Document 1 discloses a composite material in which 65-100% by weight of solid content is composed of cellulose microfibrils, ensuring high strength.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent document 1: Japanese Patent Application Publication No. 2003-201695.

[0006] In order to use the material for various purposes, it is necessary to balance strength and flexibility. Although the composite material in Patent Document 1 has high strength, it lacks flexibility.

[0007] Therefore, as a material with excellent mechanical strength and flexibility, it is necessary to provide mycelial structures. Summary of the Invention

[0008] The mycelial structure involved in the application examples of this invention has:

[0009] Mycelium consisting of hyphae connected in a three-dimensional shape and starch covering the hyphae.

[0010] The method for manufacturing mycelial structures according to the application examples of the present invention includes:

[0011] The permeation process allows the starch solution to permeate the cultured mycelium; and

[0012] The drying process involves drying the mycelium that has been permeated with the starch solution. Attached Figure Description

[0013] Figure 1 This is a process diagram illustrating the manufacturing method of the mycelial structure involved in the embodiment.

[0014] Figure 2 Table 1 shows the composition of the mycelial structure and the evaluation results of the mycelial structure in each embodiment and comparative example.

[0015] Explanation of reference numerals in the attached figures

[0016] S102, Mycelium preparation process; S104, Infiltration process; S106, Drying process. Detailed Implementation

[0017] Hereinafter, the mycelial structure and the method for manufacturing the mycelial structure of the present invention will be described in detail based on the preferred embodiments shown in the accompanying drawings.

[0018] [1] Mycelial structure

[0019] First, the mycelial structure involved in the implementation method will be described.

[0020] The mycelial structure consists of a mycelium composed of hyphae connected in a three-dimensional shape and a starchy substance covering the hyphae. This structure results in a mycelial structure with excellent mechanical strength and flexibility.

[0021] [1-1] Mycelium

[0022] The mycelium contains at least the hyphae of mushrooms. This allows for excellent flexibility in the mycelial structure.

[0023] The hyphae of mushrooms are the fibrous structures that make up the mycelium of mushrooms. As for the types of mushrooms, there are no particular limitations. Examples include: *Agaricus arvensis*, *Agrocybe brasiliensis*, *Amylomyces rouxii*, species of the genus *Amylomyces*, *Armillaria mellea*, *Aspergillus nidulans*, *Aspergillus niger*, *Aspergillus oryzae*, *Ceriporia lacerata*, *Coprinus coatus*, *Fibroporia vaillantii*, *Fistulina hepatica*, *Flammulina velutipes*, *Fomitopsis officinalis*, *Ganoderma masessile*, *Ganoderma tsugae*, and *Ganoderma*. lucidum, Hericium erinaceus, Hypholoma capnoides, Hypholoma sublateritium, Inonotus obliquus, Lactarius chrysorrheus, Macrolepidota procera, Morchella angusticeps, Myceliophthora thermophila, Neurospora crassa, Penicillium camembertii, Penicillium chrysogenum, Penicillium rubens, Phycomyces blakesleeanus, Pleurotus djamor, Pleurotus ostreatus, Polyporus squamosus, Psathyrella aquatica, Rhizopus microspores, Rhizopus oryzae, SchizophyllumThe fungi include *Streptomyces venezuelae*, *Stropharia rugosoannulata*, *Thielavia terrestris*, *Ustilago maydis*, *Lentinula*, *Meripilus*, *Grifola*, *Leucopaxillus*, *Fomitopsis*, and *Tricholoma*.

[0024] Mycelium is the substance formed by the aggregation of multiple mycelia of mushrooms. It should be noted that in the following description, mushroom mycelia will also be referred to as "mycelia".

[0025] The average diameter of the hyphae constituting the mycelium is preferably 0.2 μm or more and 4.0 μm or less, more preferably 0.3 μm or more and 3.5 μm or less, and even more preferably 0.4 μm or more and 3.0 μm or less. It should be noted that, in this invention, "hyphae constituting the mycelium" refers to the hyphae before they are covered by the starch described later. If the average diameter of the hyphae constituting the mycelium is within the specified range, a mycelial structure with particularly improved mechanical strength and flexibility can be manufactured.

[0026] It should be noted that the average diameter of the hyphae that make up the mycelium was measured as follows.

[0027] First, the mycelium was magnified and observed within a single image containing more than 100 hyphae. Next, images of at least 10 hyphae were randomly selected, and the width of each image was measured. Then, the average of these measurements was taken as the average diameter of the hyphae constituting the mycelium. It should be noted that the average diameter of the mycelium covered by starch, as described later, was also measured in the same way.

[0028] The average length of the hyphae constituting the mycelium is not particularly limited, but is preferably 0.01 mm or more and 3.0 mm or less, more preferably 0.10 mm or more and 2.0 mm or less, and even more preferably 0.50 mm or more and 1.0 mm or less. If the average length of the hyphae constituting the mycelium is within this range, then, for example, when the mycelial structure is shaped into a sheet, the hyphae are oriented along the surface of the mycelial structure, and at the same time, the hyphae moderately intertwine with each other. This, in particular, improves the mechanical strength and flexibility of the mycelial structure.

[0029] It should be noted that the average length of the hyphae that make up the mycelium was measured as follows.

[0030] First, the mycelium was magnified and observed within an image containing more than 100 hyphae. Next, images of at least 10 hyphae were randomly selected, and the maximum achievable length within each image was measured. Then, the average of these measurements was taken as the average length of the hyphae constituting the mycelium. It should be noted that the average length of the hyphae covered with starch, as described later, was also measured in the same way.

[0031] The preferred fiber density of the mycelium constituting the mycelium is 0.1 g / cm³. 3 Above and 0.8g / cm 3 The following is more preferably 0.2 g / cm³. 3 Above and 0.7g / cm 3 The following is a further preferred value: 0.3 g / cm³ 3 Above and 0.6 g / cm 3 The following applies. If the fiber density of the hyphae constituting the mycelium is within the specified range, it can particularly improve the mechanical strength and flexibility of the mycelial structure.

[0032] It should be noted that the fiber density of the mycelium that makes up the mycelium was measured as follows.

[0033] First, the weight of the mycelium was determined using an electronic balance. Next, the volume of the mycelium was measured. It should be noted that volume refers to the apparent volume, including pores. Then, by dividing the mass by the volume, the fiber density of the mycelium constituting the mycelium could be obtained. It should also be noted that the fiber density of the starch-covered mycelium, described later, was measured in the same manner.

[0034] Furthermore, the hyphae preferably contain chitin. Chitin is included as a component of the cell wall constituting the hyphae. Chitin is a high molecular weight polysaccharide with N-acetylglucosamine containing acetamide groups added to glucose as its structural units. Chitin has hydroxyl groups, so the hyphae are easily cross-linked by the cross-linking agent, for example, when a cross-linking agent described later is used to impart strength. As a result, the mechanical strength of the hyphal structure can be improved.

[0035] [1-2] Starch

[0036] In the mycelial structure, at least a portion of the hyphae are covered with starch. This results in excellent mechanical strength of the mycelial structure. It should be noted that, in the following description, starch will also be referred to simply as "starch".

[0037] Starch is a molecule composed of multiple α-glucose molecules polymerized through glycosidic bonds. Starch can be a linear molecule or contain branched chains. Starch can be derived from various plants. More specifically, it can be derived from grains such as corn, wheat, and rice; legumes such as broad beans, mung beans, and red beans; tubers such as potatoes, sweet potatoes, and cassava; wild grasses such as ferns and kudzu; and palm trees such as sago palm.

[0038] Starch can be processed starch. Examples of processed starches include: acetylated adipic acid cross-linked starch, acetylated starch, oxidized starch, sodium octenyl succinate starch, hydroxypropyl starch, hydroxypropylated phosphoric acid cross-linked starch, phosphorylated starch, phosphoric acid monoesterified phosphoric acid cross-linked starch, urea phosphorylated esterified starch, sodium starch glycolate, and high amylose corn starch. Additionally, starch can also be modified starch. Examples of modified starches include starches obtained through processing or modification of starch, specifically dextrin.

[0039] The average diameter of the starch-covered hyphae is preferably 2.0 μm or more and 20.0 μm or less, more preferably 3.0 μm or more and 18.0 μm or less, and even more preferably 4.0 μm or more and 15.0 μm or less. If the average diameter of the starch-covered hyphae is within the above range, the mechanical strength and flexibility of the hyphal structure can be further improved.

[0040] The thickness of the starch covering the mycelium is preferably 1.8 μm or more and 16.0 μm or less, more preferably 2.7 μm or more and 14.5 μm or less, and even more preferably 3.6 μm or more and 11.0 μm or less. If the thickness of the starch covering the mycelium is within this range, the mechanical strength and flexibility of the mycelial structure can be improved. It should be noted that the thickness of the starch covering the mycelium is obtained by subtracting the average diameter of the mycelium constituting the mycelium from the average diameter of the mycelium after it is covered with starch, and then dividing by 2.

[0041] Furthermore, the average diameter of the mycelia constituting the mycelium is defined as D1 (μm), and the average diameter of the mycelia after being covered with starch is defined as D2 (μm). Here, D2 / D1 is the ratio of the average diameter before and after starch coverage. D2 / D1 is preferably 1.1 or more and 20.0 or less, more preferably 1.5 or more and 15.0 or less, and even more preferably 2.0 or more and 10.0 or less. By setting the D2 / D1 ratio within the aforementioned range, the mechanical strength and flexibility of the mycelial structure can be particularly improved.

[0042] The optimal density of the mycelial structure is 0.8 g / cm³. 3 Above and 5.0 g / cm 3 The preferred value is 1.2 g / cm³. 3 Above and 4.5g / cm3 The following is a further preferred value of 1.5 g / cm³. 3 Above and 4.0 g / cm 3 The following applies. If the density of the mycelial structure is within the specified range, it can particularly improve the mechanical strength and flexibility of the mycelial structure.

[0043] The porosity of the mycelial structure is not particularly limited, but is preferably 1.0% by volume or more and 20.0% by volume or less, more preferably 2.0% by volume or more and 15.0% by volume or less, and even more preferably 3.0% by volume or more and 10.0% by volume or less.

[0044] In addition, the fiber density of the mycelium constituting the mycelium is set as M1 (g / cm³). 3 The density of the mycelial structure was set as M2 (g / cm³). 3 At this point, M2 / M1 is the mass ratio before and after starch coating. M2 / M1 is preferably 2.0 or more and 20.0 or less, more preferably 2.5 or more and 15.0 or less, and even more preferably 3.0 or more and 10.0 or less. By setting the M2 / M1 ratio within the aforementioned range, the mechanical strength and flexibility of the mycelial structure can be particularly improved.

[0045] [1-3] Other components contained in mycelium

[0046] In addition, mycelium may contain other components. Examples of other components include: plasticizers, stabilizers, antioxidants, UV absorbers, lubricants, flame retardants, antistatic agents, colorants, fillers, etc.

[0047] Examples of plasticizers include: oils, sugar alcohols, glycerol, adipate-based plasticizers, phthalate-based plasticizers, trimellitate-based plasticizers, polyester-based plasticizers, (meth)acrylate polymers, ethylene-based copolymer elastomers, chlorinated polyethylene (CPE), (meth)acrylate resins (PMMA), polystyrene resins (PS), polyvinyl acetate resins (PVAc), nitrile rubber (NBR), and styrene-butadiene rubber (SBR). By incorporating plasticizers into the mycelium, the flexibility of the mycelial structure can be improved.

[0048] Oil is a hydrophobic liquid, generally an ester of alcohols and fatty acids. Examples of oils include substances derived from plants, animals, and minerals. Examples of vegetable oils include castor oil, rapeseed oil, soybean oil, palm oil, flaxseed oil, olive oil, avocado oil, sesame oil, perilla oil, cottonseed oil, safflower oil, corn oil, rice bran oil, camellia oil, coconut oil, and peanut oil. More specifically, examples include epoxidized vegetable oils such as epoxidized soybean oil (ESBO) and epoxidized flaxseed oil (ELSO).

[0049] Examples of sugar alcohols include maltitol, lactitol, tetrasaccharide alcohol, pentitol, hexitol, erythritol, sorbitol, xylitol, mannitol, and glycerol.

[0050] The content of other components in the mycelium is not particularly limited, but is preferably 20.0% by mass or less, more preferably 15.0% by mass or less, and even more preferably 10.0% by mass or less.

[0051] [1-4] Others

[0052] The substances contained in mycelium can be cross-linked with each other using a cross-linking agent. The cross-linking agent reacts with the hydroxyl groups contained in the mycelium and fibers by applying heat. This improves the mechanical strength of the mycelial structure.

[0053] Examples of crosslinking agents include: aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, azelaic acid, and sebacic acid; aromatic dicarboxylic acids such as phthalic acid, isophthalic acid, and terephthalic acid; dicarboxylic acids with hydroxyl groups such as tartaric acid and malic acid; tricarboxylic acids such as citric acid and aconitic acid; and amino acids with multiple carboxyl groups such as aspartic acid and glutamic acid. One or a mixture of two or more of these can be used.

[0054] In addition, mycelium can be treated with ozone, deacetylated, or have its chemical bonds altered using sebacic acid, tannins, etc. These treatments can further improve the mechanical strength of the mycelial structure.

[0055] Treatments to improve the mechanical strength and flexibility of mycelial structure can be carried out individually or in combination as appropriate.

[0056] [1-5] Applications of mycelial structure

[0057] Mycelial structures can be shaped into various forms depending on their intended use. More specifically, they can be formed into, for example, sheets, plates, and meshes. Specific examples of applications include paper, non-woven fabrics, wallpaper, wrapping paper, colored paper, drawing paper, recording media, decorative sheets, fiberboard, filters, absorbent materials, sound absorbers, cushioning materials, and mats.

[0058] The mycelial structure involved in this embodiment has excellent mechanical strength and softness, so it can be used as a natural material such as a leather substitute (alternative leather).

[0059] [1-6] Characteristics of mycelial structure

[0060] As for the mycelial structure involved in this embodiment, in the stress-strain curve showing the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, the maximum stress in the elastic region is preferably 2.0 MPa or more and 40.0 MPa or less, more preferably 5.0 MPa or more and 35.0 MPa or less, and even more preferably 8.0 MPa or more and 30.0 MPa or less. This further improves the mechanical strength of the mycelial structure.

[0061] Furthermore, regarding the mycelial structure according to this embodiment, in the stress-strain curve showing the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, the maximum strain in the elastic region is preferably 0.5% or more and 4.0% or less, more preferably 1.0% or more and 3.5% or less, and even more preferably 1.5% or more and 3.0% or less. This significantly improves the flexibility of the mycelial structure.

[0062] Tensile testing can be performed using, for example, the autograph AGS-5kNX (manufactured by Shimadzu Corporation).

[0063] [2] Method for manufacturing mycelial structures

[0064] Next, an example of the method for manufacturing the mycelial structure described above will be explained.

[0065] Figure 1 This is a process diagram illustrating the manufacturing method of the mycelial structure involved in the embodiment.

[0066] Figure 1 The method for manufacturing the mycelial structure shown includes: a mycelial preparation step S102, preparing mycelia; a permeation step S104, permeating the mycelia with a starch solution; and a drying step S106, drying the permeated starch solution. Based on this configuration, a mycelial structure with excellent mechanical strength and flexibility can be manufactured.

[0067] [2-1] Mycelium preparation process

[0068] In the mycelium preparation step S102, firstly, mycelium containing mycelia is prepared. Mycelium is formed, for example, by collecting multiple mycelia and shaping or forming them into sheets. It should be noted that the mycelium can be flat or shaped into a predetermined form.

[0069] It should be noted that cultured mycelium is preferred as the mycelium. The average length of the mycelium in cultured mycelium is longer than that of the dehiscent tissue of mushroom mycelium. Therefore, the intertwining of mycelium in cultured mycelium results in a more flexible mycelial structure.

[0070] When mycelial strains are inoculated onto a culture medium and cultured, the resulting mycelium grows and spreads throughout the entire medium, forming mycelial tissue. The culture medium can be either a solid or liquid medium.

[0071] The culture medium can contain components that improve mechanical strength and flexibility. Examples of components that improve mechanical strength and flexibility include, for instance, plasticizers and cross-linking agents, as mentioned above. In addition to these components, the culture medium may also contain nutrients required for mushroom mycelial proliferation, gelling agents, etc.

[0072] When using solid culture media, sheet-shaped media can be used. This simplifies or eliminates secondary processing, enabling efficient production of sheet-like mycelia. Liquid culture media, on the other hand, are composed of nutrients, plasticizers, cross-linking agents, etc., dispersed in a dispersion medium such as water. Because of their liquid form, liquid media are easier to manage and handle. Furthermore, stirring and other operations can be performed in liquid media, facilitating uniform and rapid cultivation.

[0073] The culture conditions, such as culture temperature, culture time, and humidity, should be set appropriately according to the type of mycelium and culture medium.

[0074] In the cultured mycelium, the hyphae are interconnected in a three-dimensional shape. This gives the mycelium superior flexibility.

[0075] The cultured mycelium can be shaped as needed. This allows for the production of mycelium in the desired form.

[0076] As mycelium, mycelium that has undergone treatment to improve its mechanical strength and flexibility can be prepared. Examples of treatments to improve mechanical strength and flexibility include the addition of plasticizers and cross-linking agents, and ozone treatment.

[0077] [2-2] Penetration process

[0078] Next, in the infiltration step S104, the prepared mycelium is infiltrated with a starch solution. As the infiltration method, immersing the mycelium in the starch solution is preferred. The starch solution only needs to penetrate at least a portion of the mycelium, but it is preferable to penetrate the entire mycelium.

[0079] The starch solution is a solution containing starch and water. The starch concentration of the starch solution is preferably 3.0% by mass or more and 30.0% by mass or less, more preferably 5.0% by mass or more and 28.0% by mass or less. If the starch concentration is within this range, the starch solution can penetrate more effectively into the interior of the mycelium.

[0080] Furthermore, the starch concentration of the starch solution is preferably 15.0% by mass or more and 25.0% by mass or less, particularly preferably 18.0% by mass or more and 22.0% by mass or less. If the starch concentration is within this range, it is easier to meet the aforementioned ranges of maximum stress and maximum strain. This further improves the mechanical strength and flexibility of the mycelial structure.

[0081] Any additives can be added to starch solutions as needed. Examples of additives include condensing agents, antioxidants, stabilizers, and lubricants.

[0082] The time for immersing the mycelium in the starch solution is preferably 130 minutes or more, more preferably 145 minutes or more, and even more preferably 160 minutes or more. This allows the starch solution to penetrate into the interior of the mycelium, and in particular improves the mechanical strength and flexibility of the mycelial structure.

[0083] Furthermore, from a production point of view, the time for immersing the mycelium in the starch solution is preferably 250 minutes or less, more preferably 220 minutes or less, and even more preferably 200 minutes or less.

[0084] Furthermore, heating the starch solution during infiltration can shorten the time required for the starch solution to permeate into the entire mycelium. Additionally, reducing the viscosity of the starch solution can also shorten the infiltration time. Moreover, stirring the starch solution or applying external force to the mycelium can promote contact between the starch solution and the mycelium, thereby also shortening the infiltration time.

[0085] Alternatively, vacuum impregnation can be used as a permeation method. In this case, the required permeation time can be adjusted by regulating the vacuum level and vacuum time during impregnation.

[0086] [2-3] Drying process

[0087] In the drying process S106, the mycelium, after being permeated by the starch solution, is dried to evaporate the moisture. After the moisture evaporates, the starch coats the mycelium by wrapping around it. This improves the mechanical strength and flexibility of the mycelial structure.

[0088] As drying conditions, heating is preferably performed at 80.0°C or higher and 120.0°C or lower, more preferably at 85.0°C or higher and 115.0°C or lower, and even more preferably at 80.0°C or higher and 110.0°C or lower. This allows moisture to evaporate from the mycelium, particularly improving the mechanical strength and flexibility of the mycelial structure. However, the drying conditions are not limited to the aforementioned ranges; for example, drying at room temperature is also possible.

[0089] Drying can be carried out under atmospheric pressure or under pressure with heating. Preferably, the pressure is 40.0 kPa or higher and 230.0 kPa or lower, more preferably 45.0 kPa or higher and 225.0 kPa or lower, and even more preferably 50.0 kPa or higher and 220.0 kPa or lower. This allows for further evaporation of moisture from the mycelium, improving the mechanical strength and flexibility of the mycelial structure.

[0090] Furthermore, after the drying process, a second penetration and drying process can be performed. This allows for a thicker starch coating on the mycelium, particularly improving the mechanical strength of the mycelial structure.

[0091] [3] The effects achieved by the above implementation methods

[0092] In summary, the mycelial structure involved in the above embodiments has a mycelium composed of mycelia connected in a three-dimensional shape and starch covering the mycelia.

[0093] Based on this composition, a mycelial structure with excellent mechanical strength and flexibility can be obtained.

[0094] Furthermore, in the mycelial structure described in the above embodiment, the density is preferably 0.8 g / cm³. 3 Above and 5.0 g / cm 3 the following.

[0095] This composition is particularly effective in improving the mechanical strength and flexibility of the mycelial structure.

[0096] Furthermore, in the mycelial structure described in the above embodiments, the average diameter of the mycelia covered by starch is preferably 2.0 μm or more and 20.0 μm or less.

[0097] Based on this composition, by covering the mycelium with starch, the mechanical strength and flexibility of the mycelial structure can be further improved.

[0098] Furthermore, in the mycelial structure described in the embodiment, in the stress-strain curve showing the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, the maximum stress in the elastic region is preferably 2.0 MPa or more and 40.0 MPa or less.

[0099] This composition can further improve the mechanical strength of the mycelial structure.

[0100] Furthermore, in the mycelial structure described in the above embodiments, in the stress-strain curve showing the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, the maximum strain in the elastic region is preferably 0.5% or more and 4.0% or less.

[0101] This composition, in particular, enhances the flexibility of the mycelial structure.

[0102] Furthermore, the method for manufacturing mycelial structures according to the above embodiments includes: a permeation step S104, in which a starch solution is permeated into the cultured mycelium; and a drying step S106, in which the mycelium permeated with the starch solution is dried.

[0103] Based on this composition, mycelial structures with excellent mechanical strength and flexibility can be manufactured.

[0104] Furthermore, as a method for manufacturing the mycelial structure according to the above embodiments, in the drying step S106, it is preferable to heat the mycelium after it has been permeated with starch solution at a temperature of 80.0°C or higher and 120.0°C or lower.

[0105] Based on this composition, moisture evaporates further from the mycelium, creating a mycelial structure with significantly enhanced mechanical strength and flexibility.

[0106] Furthermore, as a method for manufacturing the mycelial structure according to the above embodiments, in the drying step S106, it is preferable to pressurize the mycelium after it has been permeated with starch solution at a pressure of 40.0 kPa or higher and 230.0 kPa or lower.

[0107] Based on this composition, moisture evaporates further from the mycelium, which can improve the mechanical strength and flexibility of the mycelial structure.

[0108] Furthermore, as a method for manufacturing the mycelial structure according to the above embodiments, the average diameter of the mycelia constituting the mycelium is preferably 0.2 μm or more and 4.0 μm or less.

[0109] Based on this composition, a mycelial structure with significantly enhanced mechanical strength and flexibility can be obtained.

[0110] Furthermore, as a method for manufacturing the mycelial structure according to the above embodiments, the fiber density of the mycelia constituting the mycelium is preferably 0.1 g / cm³. 3 Above and 0.8g / cm 3 the following.

[0111] This composition is particularly effective in improving the mechanical strength and flexibility of the mycelial structure.

[0112] Furthermore, as a method for manufacturing the mycelial structure according to the above embodiments, the starch concentration of the starch solution is preferably 3.0% by mass or more and 30.0% by mass or less.

[0113] This structure allows starch solution to penetrate the mycelium more effectively, resulting in a mycelium structure with significantly enhanced mechanical strength and flexibility.

[0114] Furthermore, as a method for manufacturing the mycelial structure according to the above embodiments, the starch concentration of the starch solution is preferably 15.0% by mass or more and 25.0% by mass or less.

[0115] Based on this configuration, it is easier to meet the aforementioned range of maximum stress and maximum strain, and it is possible to manufacture mycelial structures with further improved mechanical strength and flexibility.

[0116] The mycelial structure and its manufacturing method according to the present invention have been described above based on preferred embodiments, but the present invention is not limited thereto. For example, the mycelial structure according to the present invention can be replaced with any constituent having the same function in the embodiments described above, or any constituent can be added to the embodiments.

[0117] Furthermore, the method for manufacturing the mycelial structure of the present invention can be modified to add any desired steps to the embodiments described above.

[0118] Example

[0119] Next, specific embodiments of the present invention will be described, but the present invention is not limited thereto. In the following embodiments, the processing and measurement are carried out at room temperature (23°C) without showing temperature conditions.

[0120] [4] Fabrication of mycelial structure

[0121] [4-1] Example 1

[0122] First, prepare the mycelium obtained from the culture of Ganoderma lucidum. The average diameter of the mycelium is 2.0 μm, and the fiber density is 0.5 g / cm³. 3 .

[0123] Next, the prepared mycelium was immersed in a starch solution. A 20% by mass starch solution was used. After immersion at room temperature for 160 minutes, the mycelium was removed from the starch solution.

[0124] Then, the mycelium, after being permeated with starch solution, was heated and pressurized to evaporate the water. The heating and pressurization conditions were 100.0℃ and 50.0kPa.

[0125] The mycelial structure of Example 1 was obtained as shown above.

[0126] [4-2] Examples 2-5 and Comparative Example 1

[0127] The manufacturing conditions for mycelial structures, such as Figure 2The changes shown in Table 1 were made, but otherwise the mycelial structures of Examples 2-5 and Comparative Example 1 were obtained in the same manner as in Example 1. It should be noted that in Comparative Example 1, the starch solution was not permeated into the mycelium.

[0128] In addition, the density of the mycelial structures obtained in Examples 2-5 was 0.8 g / cm³. 3 Above and 5.0 g / cm 3 The average diameter of the hyphae covered with starch was greater than 2.0 μm and less than 20.0 μm.

[0129] [5] Evaluation of mycelial structure

[0130] First, a mycelial structure was stamped to create a test specimen. Next, a tensile test was conducted on the specimen using an autograph AGS-5kNX (manufactured by Shimadzu Corporation) according to JIS P 8113:2006. A stress-strain curve was generated showing the relationship between the stress (MPa) applied during the tensile test and the strain (%) at that point, thus determining the elastic region.

[0131] [5-1] Mechanical strength

[0132] The mechanical strength is evaluated by comparing the maximum stress within the elastic region with the following evaluation criteria. The higher the value of the maximum stress within the elastic region, the better the mechanical strength.

[0133] A: The maximum stress within the elastic region is above 8.0 MPa and below 40.0 MPa;

[0134] B: The maximum stress within the elastic region is above 6.0 MPa and below 8.0 MPa;

[0135] C: The maximum stress within the elastic region is above 4.0 MPa and below 6.0 MPa;

[0136] D: The maximum stress within the elastic region is above 2.0 MPa and below 4.0 MPa;

[0137] E: The maximum stress within the elastic region is less than 2.0 MPa.

[0138] [5-2] Softness

[0139] The flexibility is evaluated by comparing the maximum strain within the elastic region with the following evaluation criteria. The higher the maximum strain within the elastic region, the better the flexibility.

[0140] A: The maximum strain within the elastic region is greater than 1.5% and less than 4.0%;

[0141] B: The maximum strain within the elastic region is greater than 1.0% and less than 1.5%;

[0142] C: The maximum strain within the elastic region is greater than 0.5% and less than 1.0%;

[0143] D: The maximum strain within the elastic region is less than 0.5%.

[0144] These evaluation results, together with the manufacturing conditions of the mycelial structures of the various embodiments and comparative examples, are summarized in Table 1.

[0145] As shown in Table 1, the mycelial structures of the described embodiments exhibit excellent mechanical strength and flexibility. In contrast, the mycelial structures of the comparative examples did not yield satisfactory results.

[0146] Furthermore, in the drying process, the heating temperature was changed to a range of 80.0°C to 120.0°C, and the pressure conditions were changed to a range of 40.0 kPa to 230.0 kPa. Otherwise, the mycelial structures were manufactured in the same manner as in Examples 1 to 5. These mycelial structures were evaluated in the same way as described above, and the results were the same as those described above.

[0147] In addition, during the mycelial preparation process, the average diameter of the mycelia constituting the mycelium is between 0.2 μm and 4.0 μm, and the fiber density of the mycelia constituting the mycelium is between 0.1 g / cm³. 3 Above and 0.8g / cm 3 Except for the following modifications, the mycelial structures were manufactured in the same manner as in Examples 1-5. These mycelial structures were evaluated in the same way as described above, and the same results were obtained.

Claims

1. A mycelial structure, characterized in that, It has a mycelium composed of hyphae connected in a three-dimensional shape and starch covering the hyphae.

2. The mycelial structure according to claim 1, wherein, The density of the mycelial structure is 0.8 g / cm³. 3 Above and 5.0 g / cm 3 the following.

3. The mycelial structure according to claim 1 or 2, wherein, The average diameter of the hyphae covered by the starch is greater than 2.0 μm and less than 20.0 μm.

4. The mycelial structure according to claim 1 or 2, wherein, In the stress-strain curve showing the relationship between the stress applied by the tensile test and the strain at that time, The maximum stress within the elastic region is above 2.0 MPa and below 40.0 MPa. Where MPa is the unit of stress, and the unit of strain is %.

5. The mycelial structure according to claim 1 or 2, wherein, In the stress-strain curve showing the relationship between the stress applied by the tensile test and the strain at that time, The maximum strain within the elastic region is greater than 0.5% and less than 4.0%. The unit of stress is MPa, and % is the unit of strain.

6. A method for manufacturing a mycelial structure, characterized in that, have: The permeation process allows the starch solution to permeate the cultured mycelium; and The drying process involves drying the mycelium that has been permeated with the starch solution.

7. The method for manufacturing mycelial structures according to claim 6, wherein, In the drying process, the mycelium permeated with the starch solution is heated to a temperature above 80.0°C and below 120.0°C.

8. The method for manufacturing the mycelial structure according to claim 6 or 7, wherein, In the drying process, the mycelium permeated with the starch solution is pressurized to a pressure of 40.0 kPa or higher and 230.0 kPa or lower.

9. The method for manufacturing the mycelial structure according to claim 6 or 7, wherein, The average diameter of the hyphae constituting the mycelium is greater than 0.2 μm and less than 4.0 μm.

10. The method for manufacturing the mycelial structure according to claim 6 or 7, wherein, The fiber density of the mycelium constituting the mycelium is 0.1 g / cm³. 3 Above and 0.8g / cm 3 the following.

11. The method for manufacturing the mycelial structure according to claim 6 or 7, wherein, The starch concentration of the starch solution is 3.0% by mass or more and 30.0% by mass or less.

12. The method for manufacturing mycelial structures according to claim 11, wherein, The starch concentration of the starch solution is 15.0% by mass or more and 25.0% by mass or less.

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