Mycelial structure and method for producing mycelial structure

Abstract

To provide a mycelial structure with excellent mechanical strength and flexibility. Also, to provide a method for producing a mycelial structure with excellent mechanical strength and flexibility. [Solution] The mycelial structure of the present invention comprises a mycelium composed of three-dimensionally connected hyphae and a starchy substance covering the hyphae. Furthermore, the mycelial structure has a density of 0.8 g / cm³. 3 More than 5.0g / cm 3 The following is preferable. Furthermore, it is preferable that the average diameter of the starchy hyphae is 2.0 μm or more and 20.0 μm or less. In addition, in the stress-strain curve showing the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, it is preferable that the maximum stress in the elastic region is 2.0 MPa or more and 40.0 MPa or less, and the maximum strain is 0.5% or more and 4.0% or less.

Description

[Technical Field]

[0001] This invention relates to mycelial structures and methods for producing mycelial structures. [Background technology]

[0002] In recent years, there has been a growing market demand for products made from naturally derived materials that have a low environmental impact. For example, Patent Document 1 discloses a composite material in which 65 to 100% by weight of the solid content consists of cellulose microfibrils and which ensures high strength. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2003-201695 [Overview of the project] [Problems that the invention aims to solve]

[0004] In order to use materials for a variety of applications, both strength and flexibility are required. However, the composite material described in Patent Document 1 has the problem of being strong but lacking flexibility.

[0005] Therefore, there is a need to provide a mycelial structure that is excellent in terms of mechanical strength and flexibility. [Means for solving the problem]

[0006] The mycelial structure in an example of the application of the present invention is It comprises a mycelial body composed of hyphae connected in a three-dimensional manner, and a starchy substance covering the hyphae.

[0007] The method for producing mycelial structures according to an application example of the present invention is: A permeation step in which a starch solution is permeated into the mycelium obtained by cultivation, and a drying step in which the mycelium permeated with the starch solution is dried, It has.

Brief Description of the Drawings

[0008] [Figure 1] It is a process diagram showing the configuration of a method for manufacturing a mycelium structure according to an embodiment. [Figure 2] Table 1 showing the configuration of the mycelium structure and the evaluation results of the mycelium structure for each example and comparative example.

Modes for Carrying Out the Invention

[0009] Hereinafter, the mycelium structure of the present invention and the method for manufacturing the mycelium structure will be described in detail based on the preferred embodiments shown in the accompanying drawings.

[0010] [1] Mycelium structure First, the mycelium structure according to the embodiment will be described.

[0011] The mycelium structure has a mycelium composed of three-dimensionally connected mycelia and a starch substance covering the mycelia. According to such a configuration, a mycelium structure excellent in mechanical strength and flexibility can be obtained.

[0012] [1-1] Mycelium The mycelium contains at least mushroom mycelia. Thereby, the flexibility of the mycelium structure can be made excellent.

[0013] Mushroom hyphae are the fibrous structures that make up the mycelium of mushrooms. The types of mushrooms are not particularly limited, but examples include Agaricus arvensis, Agrocybe brasiliensis, Amylomyces rouxii, species of the genus Amylomyces, Armillaria mellea, Aspergillus nidulans, Aspergillus niger, Aspergillus oryzae, Ceriporia lacerata, Coprinus comatus, Fibroporia vaillantii, Fistulina hepatica, and Flammulina bertipes. Velutipes), Fomitopsis officinalis, Ganoderma sessile, Ganoderma tsugae, Ganoderma lucidum, Hericium erinaceus, Hypholoma capnoides, Hypholoma sublaterium, Inonotus obliquus, Lactarius chrysorrheus, Macrolepiota procera, Morchella angusticeps, Myceliophthora thermophila, Neurospora crassa Penicillium crassa), Penicillium camembertii, Penicillium chrysogenum, Penicillium rubensRubens, Phycomyces blakesleeanus, Pleurotus djamor, Pleurotus ostreatus, Polyporus squamosus, Psathyrella aquatica, Rhizopus microspores, Rhizopus oryzae, Schizophyllum commune, Streptomyces venezuelae, Stropharia rugosoannulata, Thielavia terrestris, Ustilago maydis, Lentinula genus, Meripilus genus, Grifola genus, Leucopaxillus genus, Fomitopsis genus, Tricholoma genus, etc.

[0014] The mycelium is a collection of multiple mycelia of mushrooms. In the following description, the mycelium of mushrooms is also simply referred to as "mycelium".

[0015] The average diameter of the mycelia 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. In the present invention, the "mycelia constituting the mycelium" refers to the mycelia before being covered with starch described later. If the average diameter of the mycelia constituting the mycelium is within the above range, a mycelium structure with particularly improved mechanical strength and flexibility can be produced.

[0016] The average diameter of the mycelia constituting the mycelium is measured as follows. First, the mycelium is magnified and observed so that more than 100 hyphae fit within a single image, and an image is obtained. Next, more than 10 hyphae are randomly selected, and the width of each hyphae is measured. The average of these measurements is then taken as the average diameter of the hyphae constituting the mycelium. The average diameter of hyphae covered with starch, as described later, is measured in the same manner.

[0017] The average length of the hyphae constituting the mycelium is not particularly limited, but is preferably 0.01 mm to 3.0 mm, more preferably 0.10 mm to 2.0 mm, and even more preferably 0.50 mm to 1.0 mm. If the average length of the hyphae constituting the mycelium is within the above range, for example, when the mycelial structure is formed into a sheet, the hyphae will be oriented along the surface of the mycelial structure and will intertwine with each other appropriately. This can particularly enhance the mechanical strength and flexibility of the mycelial structure.

[0018] The average length of the hyphae that make up the mycelium is measured as follows: First, the mycelium is magnified and observed so that more than 100 hyphae fit within a single image, and an image is obtained. Next, more than 10 hyphae are randomly selected, and the maximum length possible within each hyphae is measured. The average of these measurements is then taken as the average length of the hyphae constituting the mycelium. The average length of hyphae covered with starch, as described later, is measured in the same manner.

[0019] The fiber density of the hyphae that make up the mycelium is 0.1 g / cm³. 3 More than 0.8g / cm 3 Preferably, it is 0.2 g / cm³. 3 More than 0.7g / cm 3 It is more preferable that the following is the case: 0.3 g / cm³ 3 More than 0.6g / cm 3 The following is even more preferable: If the fiber density of the hyphae constituting the mycelium is within the aforementioned range, the mechanical strength and flexibility of the mycelial structure can be particularly enhanced.

[0020] The fiber density of the hyphae that make up the mycelium is measured as follows. First, the weight of the mycelium is measured using an electronic balance. Next, the volume of the mycelium is measured. Note that the volume is the apparent volume, including voids. Then, by dividing the mass by the volume, the fiber density of the hyphae constituting the mycelium can be obtained. The fiber density of hyphae covered with starch, which will be described later, is measured in the same manner.

[0021] Furthermore, the hyphae preferably contain chitin. Chitin is included as a component of the cell wall that makes up the hyphae. Chitin is a high molecular weight polysaccharide whose structural unit is N-acetylglucosamine, which has an acetamide group added to glucose. Because chitin has a hydroxyl group, the hyphae are more easily crosslinked by the crosslinking agent, for example, when a crosslinking agent described later is used to impart strength. This makes it possible to further improve the mechanical strength of the mycelial structure.

[0022] [1-2] Starch In mycelial structures, at least a portion of the hyphae are covered with starch. This gives the mycelial structure excellent mechanical strength. In the following explanation, starch will also be simply referred to as "starch."

[0023] Starch is a molecule formed by the polymerization of multiple α-glucose molecules via glycosidic bonds. Starch may be a linear molecule or may contain branches. As starch, for example, starch derived from various plants can be used. More specifically, for example, starch derived from grains such as corn, wheat, and rice; legumes such as broad beans, mung beans, and adzuki beans; tubers such as potatoes, sweet potatoes, and tapioca; wild grasses such as bracken and kudzu; and palms such as sago palm can be used.

[0024] The starch may be modified starch. Examples of modified starch include acetylated adipic acid cross-linked starch, acetylated starch, oxidized starch, sodium octenyl succinate starch, hydroxypropyl starch, hydroxypropylated phosphate cross-linked starch, phosphorylated starch, phosphate esterified phosphate cross-linked starch, urea phosphorylated esterified starch, sodium starch glycolate, and high amylose corn starch. The starch may also be denatured starch. Examples of denatured starch include those obtained by processing or denaturing starch, specifically dextrin.

[0025] The average diameter of the starch-covered hyphae is preferably between 2.0 μm and 20.0 μm, more preferably between 3.0 μm and 18.0 μm, and even more preferably between 4.0 μm and 15.0 μm. If the average diameter of the starch-covered hyphae is within the above range, the mechanical strength and flexibility of the mycelial structure can be further improved.

[0026] The thickness of the starch covering the hyphae is preferably 1.8 μm to 16.0 μm, more preferably 2.7 μm to 14.5 μm, and even more preferably 3.6 μm to 11.0 μm. If the thickness of the starch covering the hyphae is within the above range, the mechanical strength and flexibility of the mycelial structure can be further improved. The thickness of the starch covering the hyphae is the value obtained by subtracting the average diameter of the hyphae constituting the mycelium from the average diameter of the hyphae covered with starch, and dividing by 2.

[0027] Also, let the average diameter of the hyphae constituting the mycelium be D1 (μm), and the average diameter of the hyphae covered with starch be D2 (μm). At this time, D2 / D1 is the ratio of the average diameters before and after being covered with starch. 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 ratio of D2 / D1 within the above range, the mechanical strength and flexibility of the mycelium structure can be particularly enhanced.

[0028] The density of the mycelium structure is 0.8 g / cm 3 or more and 5.0 g / cm 3 or less, preferably 1.2 g / cm 3 or more and 4.5 g / cm 3 or less, more preferably 1.5 g / cm 3 or more and 4.0 g / cm 3 or less. If the density of the mycelium structure is within the above range, the mechanical strength and flexibility of the mycelium structure can be particularly improved.

[0029] The porosity of the mycelium 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.

[0030] Also, let the fiber density of the hyphae constituting the mycelium be M1 (g / cm 3 ), and the density of the mycelium structure be M2 (g / cm<000​​​​​​Furthermore, the mycelium may contain other components. Examples of other components include plasticizers, stabilizers, antioxidants, UV absorbers, lubricants, flame retardants, antistatic agents, colorants, and fillers.

[0032] Examples of plasticizers include oils, sugar alcohols, glycerin, adipic acid ester plasticizers, phthalate ester plasticizers, trimellitic acid ester plasticizers, polyester plasticizers, (meth)acrylic acid ester polymers, ethylene copolymer elastomers, chlorinated polyethylene (CPE), (meth)acrylic resins (PMMA), polystyrene resins (PS), polyvinyl acetate resins (PVAc), acrylonitrile butadiene rubber (NBR), and styrene butadiene rubber (SBR). The inclusion of plasticizers in the mycelium can increase the flexibility of the mycelial structure.

[0033] Oil is a hydrophobic liquid and is generally an ester of an alcohol and a fatty acid. Examples of oils include those derived from plants, animals, and minerals. Examples of vegetable oils include castor oil, rapeseed oil, soybean oil, coconut oil, linseed 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, epoxidized vegetable oils such as epoxidized soybean oil (ESBO) and epoxidized linseed oil (ELSO) are also examples.

[0034] Examples of sugar alcohols include maltitol, lactitol, tetriitol, pentitol, hexitol, erythritol, sorbitol, xylitol, mannitol, and glycerin.

[0035] 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.

[0036] [1-4] Others The substances contained within the mycelium may be cross-linked by a cross-linking agent. When heat is applied, the cross-linking agent reacts with the hydroxyl groups contained in the mycelium and fibers. This can improve the mechanical strength of the mycelial structure.

[0037] Examples of crosslinking agents include aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic 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 more of these can be used.

[0038] Furthermore, the mycelium may be treated to alter its chemical bonding by methods such as ozone treatment, deacetylation, sebacic acid, or tannins. These treatments can further improve the mechanical strength of the mycelial structure.

[0039] Treatments to improve the mechanical strength and flexibility of the mycelial structure may be performed individually or in combination as appropriate.

[0040] [1-5] Uses of mycelial structure The mycelial structure can be molded into various shapes depending on its intended use. More specifically, it can be molded into sheets, boards, webs, etc. Specific examples of applications include paper, nonwoven fabrics, wallpaper, wrapping paper, colored paper, drawing paper, recording media, decorative sheets, fiberboards, filters, liquid absorbents, sound absorbers, cushioning materials, mats, and the like.

[0041] The mycelial structure according to this embodiment is particularly useful as a natural material, such as a leather substitute (alternative leather), because it exhibits excellent mechanical strength and flexibility.

[0042] [1-6] Characteristics of mycelial structure In this embodiment, the mycelial structure preferably has a maximum stress in the elastic region of 2.0 MPa to 40.0 MPa in the stress-strain curve showing the relationship between the stress (MPa) applied by a tensile test and the strain (%) at that time, more preferably 5.0 MPa to 35.0 MPa, and even more preferably 8.0 MPa to 30.0 MPa. This further enhances the mechanical strength of the mycelial structure.

[0043] Furthermore, in the mycelial structure according to this embodiment, the stress-strain curve showing the relationship between the stress (MPa) applied by a tensile test and the strain (%) at that time preferably has a maximum strain in the elastic region of 0.5% to 4.0%, more preferably 1.0% to 3.5%, and even more preferably 1.5% to 3.0%. This particularly improves the flexibility of the mycelial structure.

[0044] For tensile testing, for example, an Autograph AGS-5kNX (manufactured by Shimadzu Corporation) can be used.

[0045] [2] Method for producing mycelial structures Next, we will describe an example of a method for producing the mycelial structure mentioned above. Figure 1 is a process diagram showing the configuration of a method for producing a mycelial structure according to an embodiment.

[0046] The method for producing the mycelial structure shown in Figure 1 comprises a mycelial preparation step S102 in which the mycelium is prepared, an impregnation step S104 in which starch solution is impregnated into the mycelium, and a drying step S106 in which the impregnated starch solution is dried. With this configuration, a mycelial structure with excellent mechanical strength and flexibility can be produced.

[0047] [2-1] Mycelial preparation process In the mycelial preparation step S102, first, a mycelial body containing hyphae is prepared. The mycelial body is formed, for example, by gathering a large number of hyphae and shaping or papermaking them into a sheet. The mycelial body may be in the form of a flat plate or shaped into a predetermined form.

[0048] Furthermore, it is preferable to use mycelium obtained by cultivation. The average length of the hyphae in cultured mycelium is longer than that of the fibrous mycelium of mushrooms. Therefore, in cultured mycelium, the hyphae intertwine, which can improve the flexibility of the mycelial structure.

[0049] When a mycelial spawn is inoculated into a culture medium and cultured, a mycelial body can be obtained in which the grown hyphae spread throughout the entire medium. The culture medium may be a solid medium or a liquid medium.

[0050] The culture medium may contain components that improve mechanical strength and flexibility. Examples of components that improve mechanical strength and flexibility include plasticizers and crosslinking agents, as mentioned above. In addition to these components, the culture medium may also contain nutrients necessary for the growth of mushroom mycelium, gelling agents, etc.

[0051] In the case of solid culture media, a sheet-shaped medium may be used. This simplifies or eliminates secondary processing, allowing for the efficient production of sheet-shaped mycelium. Liquid culture media, on the other hand, consist of nutrients, plasticizers, crosslinking agents, etc., dispersed in a dispersion medium such as water. When using liquid culture media, management and handling of the medium are relatively easy because it is in liquid form. Furthermore, since stirring and other operations are possible with liquid culture media, it is easy to achieve uniformity and accelerate cultivation.

[0052] Culture conditions such as culture temperature, culture time, and humidity are set appropriately according to the type of mycelium and culture medium.

[0053] In mycelium obtained through cultivation, the hyphae are connected in a three-dimensional manner. This allows for greater flexibility in the mycelium.

[0054] The mycelium obtained by culturing may be shaped as needed. This makes it possible to obtain mycelium in the desired shape.

[0055] As for the mycelium, it may be prepared that has been treated to improve its mechanical strength and flexibility. Examples of treatments to improve mechanical strength and flexibility include the addition of plasticizers and crosslinking agents, and ozone treatment.

[0056] [2-2] Penetration process Next, in the infiltration step S104, the prepared mycelium is infiltrated into the starch solution. A preferred method of infiltration is to immerse the mycelium in the starch solution. It is sufficient for the starch solution to penetrate at least a portion of the mycelium, but it is preferable for it to penetrate the entire mycelium.

[0057] 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, and more preferably 5.0% by mass or more and 28.0% by mass or less. If the starch concentration is within the above range, the starch solution can penetrate more efficiently into the interior of the mycelium.

[0058] Furthermore, the starch concentration of the starch solution is more preferably between 15.0% by mass and 25.0% by mass, and particularly preferably between 18.0% by mass and 22.0% by mass. If the starch concentration is within the above range, the ranges of maximum stress and maximum strain described above can be more easily met. This makes it possible to further enhance the mechanical strength and flexibility of the mycelial structure.

[0059] The starch solution may contain any additives as needed. Examples of additives include condensing agents, antioxidants, stabilizers, and lubricants.

[0060] The immersion time of 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 deep into the mycelium, particularly enhancing the mechanical strength and flexibility of the mycelial structure.

[0061] Furthermore, from the viewpoint of productivity, 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.

[0062] Furthermore, heating the starch solution during the infiltration process can shorten the time it takes for the starch solution to penetrate the entire mycelium. Lowering the viscosity of the starch solution can also shorten the infiltration time. Additionally, stirring the starch solution or applying external force to the mycelium can promote contact between the starch solution and the mycelium, thereby shortening the infiltration time.

[0063] Alternatively, vacuum impregnation may be used as the penetration method. In this case, the time required for penetration can be adjusted by adjusting the degree of vacuum and the vacuum duration during impregnation.

[0064] [2-3] Drying process In drying step S106, the mycelium impregnated with starch solution is dried, and the moisture is evaporated. As the moisture evaporates, the starch coats the mycelium, clinging to it. This increases the mechanical strength and flexibility of the mycelial structure.

[0065] The drying conditions are preferably 80.0°C to 120.0°C, more preferably 85.0°C to 115.0°C, and even more preferably 80.0°C to 110.0°C. This allows more moisture to evaporate from the mycelium, particularly increasing the mechanical strength and flexibility of the mycelial structure. However, the drying conditions are not limited to the above ranges, and drying may also be done at room temperature, for example.

[0066] Drying may be carried out under atmospheric pressure, or it may be carried out under pressurized conditions by heating and pressurizing. In that case, the pressurized conditions are preferably 40.0 kPa to 230.0 kPa, more preferably 45.0 kPa to 225.0 kPa, and even more preferably 50.0 kPa to 220.0 kPa. This allows for further evaporation of moisture from the mycelium, improving the mechanical strength and flexibility of the mycelial structure.

[0067] Furthermore, the infiltration and drying processes may be repeated after the drying process. This allows for a thicker starch coating on the mycelium, particularly improving the mechanical strength of the mycelial structure.

[0068] [3] Effects of the above embodiment As described above, the mycelial structure according to the embodiment comprises a mycelium composed of hyphae connected in a three-dimensional manner, and a starchy substance covering the hyphae. This configuration yields a mycelial structure with excellent mechanical strength and flexibility.

[0069] Furthermore, in the mycelial structure according to the above embodiment, the density is 0.8 g / cm³. 3 More than 5.0g / cm 3 The following is preferable:

[0070] This configuration can particularly improve the mechanical strength and flexibility of the mycelial structure.

[0071] Furthermore, in the mycelial structure according to the above embodiment, it is preferable that the average diameter of the starchy hyphae is 2.0 μm or more and 20.0 μm or less.

[0072] With this configuration, the hyphae are covered with starch, which further improves the mechanical strength and flexibility of the mycelial structure.

[0073] Furthermore, in the mycelial structure according to the above embodiment, it is preferable that the maximum stress in the elastic region of the stress-strain curve, which shows the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, is between 2.0 MPa and 40.0 MPa. This configuration allows for further enhancement of the mechanical strength of the mycelial structure.

[0074] Furthermore, in the mycelial structure according to the above embodiment, it is preferable that the maximum strain in the elastic region of the stress-strain curve, which shows the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, is 0.5% or more and 4.0% or less. This configuration can particularly improve the flexibility of the mycelial structure.

[0075] Furthermore, the method for producing the mycelial structure according to the above embodiment includes an impregnation step S104 in which a starch solution is impregnated into the mycelium obtained by culturing, and a drying step S106 in which the mycelium impregnated with the starch solution is dried.

[0076] This configuration makes it possible to produce a mycelial structure with excellent mechanical strength and flexibility.

[0077] Furthermore, in the method for producing the mycelial structure according to the above embodiment, it is preferable to heat the mycelium permeated with the starch solution at a temperature of 80.0°C to 120.0°C during the drying step S106.

[0078] With this configuration, more water evaporates from the mycelium, and a mycelial structure with particularly improved mechanical strength and flexibility can be produced.

[0079] Furthermore, in the method for producing the mycelial structure according to the above embodiment, it is preferable to pressurize the mycelium permeated with the starch solution at a pressure of 40.0 kPa or more and 230.0 kPa or less during the drying step S106.

[0080] With this configuration, more water can evaporate from the mycelium, improving the mechanical strength and flexibility of the mycelial structure.

[0081] Furthermore, in the method for producing the mycelial structure according to the above embodiment, it is preferable that the average diameter of the hyphae constituting the mycelium is 0.2 μm or more and 4.0 μm or less.

[0082] This configuration makes it possible to produce mycelial structures with particularly improved mechanical strength and flexibility.

[0083] Furthermore, in the method for producing the mycelial structure according to the above embodiment, the fiber density of the hyphae constituting the mycelium is 0.1 g / cm³. 3 More than 0.8g / cm 3 The following is preferable:

[0084] This configuration allows for particularly enhanced mechanical strength and flexibility of the mycelial structure.

[0085] Furthermore, in the method for producing the mycelial structure according to the above embodiment, it is preferable that the starch concentration of the starch solution is 3.0% by mass or more and 30.0% by mass or less.

[0086] This configuration allows the starch solution to penetrate more efficiently into the mycelium, making it possible to produce a mycelial structure with particularly improved mechanical strength and flexibility.

[0087] Furthermore, in the method for producing the mycelial structure according to the above embodiment, it is preferable that the starch concentration of the starch solution is 15.0% by mass or more and 25.0% by mass or less.

[0088] With this configuration, the aforementioned ranges of maximum stress and maximum strain can be more easily met, and a mycelial structure with even greater mechanical strength and flexibility can be manufactured.

[0089] Although the mycelial structure and method for producing the mycelial structure of the present invention have been described above based on preferred embodiments, the present invention is not limited thereto. For example, the mycelial structure according to the present invention may be obtained by replacing each part of the above embodiments with any component having a similar function, or by adding any component to the above embodiments.

[0090] Furthermore, the method for producing the mycelial structure of the present invention may be modified by adding any desired steps to the above embodiment. [Examples]

[0091] Next, specific examples of the present invention will be described, but the present invention is not limited thereto. In the following examples, processes and measurements where the temperature conditions are not specified were performed at room temperature (23°C).

[0092] [4] Production of mycelial structure [4-1] Example 1 First, mycelium was prepared by culturing the spawn (Reishi mushroom). The hyphae that make up the mycelium have an average diameter of 2.0 μm and a fiber density of 0.5 g / cm². 3 That was the case.

[0093] Next, the prepared mycelium was immersed in a starch solution. A starch solution with a concentration of 20% by mass was used. After immersion at room temperature for 160 minutes, the mycelium was removed from the starch solution.

[0094] Subsequently, the mycelium impregnated with starch solution was heated and pressurized to evaporate the water. The heating and pressurizing conditions were 100.0°C and 50.0 kPa. The mycelial structure of Example 1 was obtained in the manner described above.

[0095] [4-2] Examples 2-5 and Comparative Example 1 Except for changing the manufacturing conditions of the mycelial structure as shown in Figure 2 (Table 1), the mycelial structures of Examples 2-5 and Comparative Example 1 were obtained in the same manner as in Example 1. In Comparative Example 1, the mycelium was not impregnated with starch solution.

[0096] Furthermore, the mycelial structures obtained in Examples 2-5 had a density of 0.8 g / cm³. 3 More than 5.0g / cm 3 The average diameter of the starchy hyphae was between 2.0 μm and 20.0 μm.

[0097] [5] Evaluation of mycelial structure First, the mycelial structure was punched out to prepare test specimens. Next, tensile tests were performed on the test specimens using an Autograph AGS-5kNX (Shimadzu Corporation) in accordance with JIS P 8113:2006. A stress-strain curve was created showing the relationship between the stress (MPa) applied by the tensile test and the strain (%) at that time, and the elastic region was identified.

[0098] [5-1] Mechanical strength The mechanical strength was evaluated by comparing the maximum stress in the elastic region with the following evaluation criteria. A higher value for the maximum stress in the elastic region indicates superior mechanical strength.

[0099] A: The maximum stress in the elastic range is between 8.0 MPa and 40.0 MPa. B: Maximum stress in the elastic region is 6.0 MPa or more and less than 8.0 MPa. C: Maximum stress in the elastic region is 4.0 MPa or more and less than 6.0 MPa. D: Maximum stress in the elastic region is between 2.0 MPa and less than 4.0 MPa. E: Maximum stress in the elastic region is less than 2.0 MPa

[0100] [5-2] Flexibility The flexibility was evaluated by comparing the maximum strain in the elastic range with the following evaluation criteria. A higher value for the maximum strain in the elastic range indicates greater flexibility.

[0101] A: Maximum strain in the elastic range is between 1.5% and 4.0%. B: Maximum strain in the elastic region is 1.0% or more and less than 1.5% C: Maximum strain in the elastic region is 0.5% or more and less than 1.0%. D: Maximum strain in the elastic region is less than 0.5%

[0102] These evaluation results, along with the manufacturing conditions for the mycelial structures of each of the above examples and comparative examples, are summarized in Table 1.

[0103] As is clear from Table 1, the mycelial structures of each of the above examples exhibited excellent mechanical strength and flexibility. In contrast, the mycelial structures of the comparative examples did not yield satisfactory results.

[0104] Furthermore, mycelial structures were produced in the same manner as in Examples 1 to 5, except that the heating temperature was varied within the range of 80.0°C to 120.0°C and the pressurizing conditions were varied within the range of 40.0 kPa to 230.0 kPa during the drying process. When these mycelial structures were evaluated in the same manner as described above, the same results were obtained.

[0105] Furthermore, in the mycelial preparation process, the average diameter of the hyphae constituting the mycelium is set to be between 0.2 μm and 4.0 μm, and the fiber density of the hyphae constituting the mycelium is set to be 0.1 g / cm³. 3 More than 0.8g / cm 3 Mycelial structures were produced in the same manner as in Examples 1 to 5, except for various modifications within the following range. When these mycelial structures were evaluated in the same manner as above, the same results were obtained. [Explanation of Symbols]

[0106] S102...Mycelium preparation process, S104...Infiltration process, S106...Drying process

Claims

1. A mycelial structure characterized by having a mycelial body composed of hyphae connected in a three-dimensional manner, and a starchy substance covering the hyphae.

2. The density is 0.8 g / cm³. ３ 5.0g / cm or more ３ The mycelial structure according to claim 1, which is as follows:

3. The mycelial structure according to claim 1 or 2, wherein the average diameter of the mycelium covered with the starch is 2.0 μm or more and 20.0 μm or less.

4. In a stress-strain curve showing the relationship between the stress (MPa) applied by a tensile test and the strain (%) at that time, The mycelial structure according to claim 1 or 2, wherein the maximum stress in the elastic region is 2.0 MPa or more and 40.0 MPa or less.

5. In a stress-strain curve showing the relationship between the stress (MPa) applied by a tensile test and the strain (%) at that time, The mycelial structure according to claim 1 or 2, wherein the maximum strain in the elastic region is 0.5% or more and 4.0% or less.

6. A permeation step in which a starch solution is permeated into the mycelium obtained by cultivation, and a drying step in which the mycelium permeated with the starch solution is dried, A method for producing a mycelial structure, characterized by having the following characteristics.

7. The method for producing a mycelial structure according to claim 6, wherein in the drying step, the mycelium in which the starch solution has permeated is heated at 80.0°C or higher and 120.0°C or lower.

8. A method for producing a mycelial structure according to claim 6 or 7, wherein in the drying step, the mycelium in which the starch solution has permeated is pressurized at 40.0 kPa or more and 230.0 kPa or less.

9. A method for producing a mycelial structure according to claim 6 or 7, wherein the average diameter of the hyphae constituting the mycelium is 0.2 μm or more and 4.0 μm or less.

10. The fiber density of the hyphae constituting the mycelium is 0.1 g / cm³. ３ 0.8g / cm or more ３ A method for producing a mycelial structure according to claim 6 or 7, which is as follows:

11. The method for producing a 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 producing a mycelial structure 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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