GB2265153A - Substrate and method for culture of fungi, including shiitake (lentinus edodes) - Google Patents

Abstract

An improved substrate and method for culturing fungi, including shiitake. The substrate is essentially cellulose-free and comprises a major portion of grain and preferably minor portions of nutritional supplements. The grain is preferably sterilized by boiling in order to kill bacteria, and may be cooled in order to induce germination of the heat resistant spores, then preferably steam sterilized before the germinated spores have matured sufficiently to create new spores. The substrate is inoculated with fungi, which are then cultured.

Description

SUBSTRATE AND METHOD FOR CULTURE OF FUNGI, INCLUDING SHIITAKE (LENTINUS EDODES) Technical Field.

This invention relates to the cultivation of mushrooms and other fungi, especially shiitake (Lentinus edodes.

Background Art.

Inventors have long sought a method for efficiently and quickly cultivating fungi, especially Shiitake, because of its great demand and relatively limited supply.

Shiitake and other mushrooms art usually cultivated on logs or in cellulose based substrates.

Among the methods using a cellulose basea substrate are those described in U.S. Patent No. 4,127,965 to Mee and U.S. Patent No. 4,637,163 to Pellinen. Mee also teaches the use of a cellulose based substrate in a microorganism impermeable flexible container which is then sealed and sterilized. However, as taught by U.S. Patent No. 4,674,228 issued to Murata, removal of the mycelium from such container often causes damage that reduces productivity. Other methods also have been tried. For example, U.S.

Patent No. 4,735,014 to Weber teaches the use of hemp stalks and U.S. Patent No. 4,741,122 to Becsy teaches the use of agricultural wastes.

There are many drawbacks to the various methods for growing shiitake currently in use. Growing shiitake on logs in the traditional manner is slow and inefficient. Cultivation of shiitake in microorganism impermeable flexible containers (commonly known as "space bags") offers advantages over traditional methods, but still does not provide a satisfactory production rate.

Thus, it is an object of this invention to provide an improved method of cultivating fungi, especially shiitake.

It is a further object of this invention to provide an improved culture medium for the culture of fungi, including shiitake.

It is a further object of this invention to provide a more efficient and faster method of raising fungi, including shiitake.

Disclosure of Invention.

The invention is a new substrate for the growth of fungi, especially shiitake, created using a new method of sterilizing the substrate to allow cultivation of the desired fungi without contamination by competing organisms.

The new substrate is grain that is essentially cellulose free and that has been sterilized in accordance with the process described herein. As indicated above, the prior art in the growth of mushrooms and other fungi requires growth on logs, sawdust or other substrates containing a major portion of cellulose. However, cellulose is not necessary for the cultivation of shiitake. Shiitake mushrooms have the-Sbility to break down cellulose for essential nutrients, but can be more efficiently grown in a substrate containing these materials in an already usable form. Similarly, shiitake can break down lignin, which is a constituent of wood, but again shiitake can be cultivated more efficiently by providing the breakdown products instead of the lignin.

Prior art references have taught the use of grain as a nutritional supplement in a cellulose based substrate. See for example, Han, et. al, Physiology and Ecology of Lentinus Edodes (Berk sing., Mushroom Science XI, Proceedings of the Eleventh International Scientific Congress on the Cultivation of Edible Fungi (1981). However, the substrate of this invention is essentially free of cellulose and the grain itself is the substrate.

The grain substrate must be sterilized for the cultivation of fungi, including shiitake.

Unsterilized grain contains various bacteria and microorganisms that compete with mushrooms and other fungi and therefore reduce production efficiency.

Further, conventional heat sterilization techniques, such as steam sterilization, are insufficient to sterilize the grain against all competing microorganisms. Accordingly, conventionally sterilized grain is unsuitable as a substrate. In fact, one prior art reference states that, in view of the well-established use of tree logs and the amount of energy necessary to sterilize a ~ -lsstrate, widespread large scale use of any sterilized substrate to produce shiitake mushroom appears unlikely." San Antonio, "Cultivation of the Shiitake Mushroom', Hortsc ence, Vol. 16(2), April 1981.

The main problem with conventional heat sterilization of grain substrates is that certain bacteria, primarily of the genus Bacillus, form heat resistant spores that will survive such sterilization even though the bacteria themselves are killed.

Accordingly, even though a grain substrate may be conventionally heat sterilized, it will still contain spores of Bacillus bacteria which will contaminate the substrate and render it unsuitable for production of fungi, including shiitake. This invention solves the problem of bacterial contamination in the grain so that an appropriately sterile substrate is provided.

In the invention, the substrate is boiled to kill the bacteria that are present. The substrate is then cooled to induce any heat resistant spores to germinate. The substrate then is steam sterilized after such germination, but before the bacteria have matured sufficiently to form heat-resistant spores.

Of course, non-heating methods of sterilizing the grain substrate also can be used, such as irradiation. However, irradiation of the substrate would require greater governmental regulation and may affect marketability of the resulting mushrooms.

Other non-heating methods of sterilization could include, for example, chemical sterilization (in which chemical agents in solid, liquid or gaseous form are used for sterilization) or pressure sterilization (in which the substrate is subjected to extremes of high or low pressure (including vacuum), or both).

Of course, freezing can be used with the invention as well.

The invention can be practiced with the listed sterilization methods and all other sterilization methods that kill bacteria or other spore-forming microorganisms, but that normally leave surviving spores. As long as the spores are allowed to germinate after an initial sterilization, a second sterilization that kills the bacteria or other microorganisms will completely sterilize the substrate, if the second sterilization takes place before the bacteria or other microorganisms have matured sufficiently to form new spores. Thus, the particular methods of initial and secondary sterilization are not critical, as long as the spores are allowed to germinate after initial sterilization and the substrate is secondarily sterilized before the spores mature sufficiently to form new spores.

The substrate of the invention thus provides a more efficient medium for cultivation of mushrooms, including shiitake, because the nutrients required by the mushrooms are furnished directly, rather than being furnished in the form of cellulose and lignin that must be enzymatically broken down by the mushrooms. The invention also provides a more efficient method of cultivating mushrooms because competing microorganisms, including bacteria, are eliminated rom t:.e subs:-ate.

An advantage f the invention is the shortening of incubation '-es fer the shiitake. The invention shortens the incubation t-e for forming mycelium to 21 days, as -posed to log cultivation, which requires 8 months to @ year or incubation, and sawdust based su-strates, which require approximately 80 days ror incubation.

A further advantage of the invention is the increase in yield per pound of substrate. One hundred pounds of the substrate of the invention yields approximately 300 pounds (136.1 Kg) of shiitake within 5 months. By comparison, 100 pounds (45.4 Kg) of logs yields approximately 10 to 15 pounds (4.5 to 7 Kg) of shiitake over more than 3 years, and 100 pounds (45.4 Kg) of sawdust based substrate yields approximately 80 pounds (36.3 Kg) of shiitake over 8 months.

A further advantage of the invention is that no special spawn material is necessary. The same material used for fruiting can be used as a spawn material to start new production units, so that production can be increased immediately instead of waiting for new spawn to be grown. Similarly, no spawn is wasted if production is decreased.

A still further advantage of the invention is that production units may be kept in incubation beyond the 21 day period for up to 6 months if, for example, market conditions are unfavorable. This also allows stockpiling of colonized units for large seasonal production outputs.

In the practice of the invention, various nutritional supplements (including proteins, sugars, starches and vitamins) are boiled in water until they are dispersed throughout the mixture. The grain for the substrate is then added and boiled for approximately one hour in order to kill the bacteria present and cause the absorption of the dispersed nutritional supplements into the grain. The grain is then allowed to cool to induce germination of any heat-resistant spores. While the grain is cooling, it is mixed with permeability enhancing powders to prevent caking d packed into microorganism impermeable sterilizable containers, such as polypropylene bags.The bags are then steam sterilized in accordance with conventional practice before the germinated bacteria have matured sufficiently to orm spores.

After sterilization of the bags, colonization of the bags is acscnplished by introducing either pure spawn of the desired fungi or by introducing previously colonized grain The bags are then shaken to mix the spawn or previously colonized grain with the grain in order to decrease the incubation time.

The bags are then incubated for approximately three weeks at approximately 800 Fahrenheit (26.60C).

During this time, the spawn will digest most, if not all, of the substrate to form a mycelium.

The mycelium can then be induced to fruit by subjecting the bags to a cold shock of 40 to 65 degrees Fahrenheit (4.4 to 18.3"C) for 5 to 15 days under cool white fluorescent lighting. After the cold shock, fruiting to maturation is accomplished by removing the mycelium from the containers and exposing them to an intermittent chilled water mist, or otherwise placing the mycelium in a high humidity environment.

Alternatively, fruiting can be induced using only a cold water spray under lighter conditions Brief Description of Drawing.

Figure 1 is a flow chart of a preferred method of preparing the substrate of the invention.

Best Mode for Ca voinc Out Invention.

Figure 1 of the drawings sets forth generally a preferred method of preparing the substrate of the invention.

The ingredient5 ~in the substrate are preferably chosen to provide optimum nutrition for the fungi to be grown without requiring additional artificial supplements. This use of all-natural materials therefore makes sale and marketing of the cultivated fungi easier because fewer regulatory requirements are imposed. The preferred ingredients, their ranges and the optimum amounts are set forth below for preparing batches of the substrate.

Optimum ingredient Ranee Amount Whole Sorghum grain 150-300 ibs 200 (68.0-136.1 Kg) (90.7 Kg) Whole Oat grain 0-50 lbs 35 (0-22.7 Kg) (15.9 Kg) Russet Potatoes 5-20 lbs 10 (2.3-9.1 Kg) (4.5 Kg) Rolled Barley grain 0.5-15 ibs 5 (0.22-6.8 Kg) (2.3 Kg) Maple pea sprouts 0-15 ibs 5 (0-6.8 Kg) (2.3 Kg) Brewer's yeast powder 2-35 ibs 6 (0.9-15.9 Kg) (2.7 Kg) Hulled sunflower seed 0-10 lbs 2 (0-4.5 Kg) (0.9 Kg) Soybean meal 0-2.5 lbs 1.5 (0-1.1 Kg) (0.7 Kg) Corn gluten meal 0-2.5 lbs 1.5 (0-1.1 Kg) (0.7 Kg) Whole garlic 0-5.4 lb 1.5 (0.22-1.8 Kg) (0.7 Kg) Sunflower oil 0-20 tablespoons 10 (0-300 ml) (150 ml) Wheat germ oil -~ 0-20 tablespoons 10 (0-300 ml) (150 ml) Molasses 0-20 tablespoons 6 (0-300 ml) (90 ml) Water 20-35 gallons 25 (0.076-0.132 m3) (0.095 m3) Milk 0-1 gallon .25 (0-0.0038 m3) (0.00095 m3) The preferred coating ingredients, the ranges and the optimum for every two batches of the above substrate are set forth below: Limestone powder 25-75 lbs 50 (11.3-34 Kg) (22.7 Kg) Gypsum powder 100-200 lbs 160 (45.4-90.8 Kg) (72.6 Kg) Cottonseed meal 0-60 lbs 40 (0-27.2 Kg) (18.1 Kg) The maple pea sprouts are preferably grown for 6 to 12 days under a mist system. Commercial bean sprouts may also be used, but more roots and larger cotyledons are available with maple pea sprouts.

Sorghum provides vitamins, carbohydrates, starches, protein and minerals such as Copper, Iron, Manganese, Zinc and Selenium. Oats provide vitamins, minerals, carbohydrates, starches, proteins and salicylic acid. Salicylic acid promotes shiitake fruiting. Rolled barley grain provides vitamins and carbohydrates and absorbs excess water. Soybean meal provides a source of minerals, proteins and vitamins.

Brewer' s yeast powder provides high amounts of vitamins, especially B vitamins that promote mycelial growth. Sunflower seed and sunflower oil provide vitamins, minerals, proteins and saturated and unsaturated oils. The sunflower seed and oil also promote heavier secondary mycelial growth.

The pea sprouts promote a heavier amount of fruiting to occur. This allows some control over the size of the mushrooms. More sprouts allow for more mushrooms to erm but the mushrooms are smaller in size. Fewer sprouts allow for fewer mushrooms to for: but the mushrooms are larger in size. With no sprouts added, mushrooms with individual weights of from to 1 lbs (0.34-0.68 Kg) may form on the substrate.

Garlic provides natural antibacterial action in order to resist bacterial growth after boiling and sterilization of the substrate. Molasses provides sugars and wheat gesm oil provides saturated and unsaturated oils as well as vitamin D. Corn gluten meal provides vitamins, minerals, protein and selenium. Potatoes provide starch. Milk provides cassein and cheese can be substituted instead of milk.

The coating ingredients serve additional functions besides increasing permeability of the substrate. Limestone powder adjusts the pH of the substrate to neutral (approximately 7 to 8). The gypsum powder also provides long tesm pH maintenance and makes the grain substrate loose and powdery. The cottonseed meal provides protein and oil.

It should be noted that the prior art teaches that, under certain conditions, calcium inhibits fruiting of mycelium. However, the substrate of this invention contains substantial amounts of calcium from the limestone and gypsum powder.

The size and number of mushrooms can be controlled prior to colonization by the amount of substrate that is packed in the bags, with larger bags that contain more substrate producing larger and more mushrooms. For example, eight pound (3.6 Kg) bags will produce 3 pound (0.34 Kg) mushrooms for approximately 6 months.

Mushroom size and number can also be controlled after colonization by allowing individual colonized units to come into contact with each other. The individual units will for3 one large continuous unit forming larger and more numerous mushrooms than an individual unit.

Fully colonized units can be placed on shelving or strung on rods to maximize production per unit area.

The following example illustrates the use of this invention using the optimum amounts set forth above.

EXAMPLE The water is boiled in a 60 US gallon (0.227 m3) capacity kettle with a bottom spigot. The potatoes are sliced and then added to the boiling water together with the milk, garlic, corn gluten meal, wheat germ oil, sunflower oil, molasses, hulled sunflower seed, brewer's yeast powder and soybean meal The mixture is then boiled until all components break into small pieces. The mixture is preferably mixed with a portable paint mixer to help break clumps into small pieces. Maple pea sprouts are then added to the boiling mixture, which is stirred with a large paddle until the sprouts are soft. The oat grain, barley grain and sorghum grain are then added, together with sufficient water only to cover the grain.The mixture is then boiled and stirred until the water level falls below the grain level by 3 to 4 inches (7.6 to 10.2 cm) and the heat source is then turned off. After.

approximately one hour, any remaining liquid is drawn off from the bottom of the pot. At this point, the grain should be half-cooked and semi-hard. The grain is then allowed to cool for approximately 24 hours, at which time it is removed from the pot.

Two batches of grain are then placed in a large flat bin and the limestone powder, gypsum powder and cottonseed meal are mixed with the grain until all the grain is coated with powder. The grain should appear coated and should not stick in clumps. Two batches will yield approximately 1,200 pounds (544 Kg) of prepared substrate.

The prepared substrate is then packed into double polypropylene plastics bags (1.5 mil.). Each of these double bag units has a polypropylene collar, a cotton plug and an aluminium foil cover over the plug. The bags from 4 batches of the grain (approximately 2,400 pounds - 1088 Kg) are then loaded in a steam retort - 5 foot (152 cm) diameter, 13 feet (396 cm) long - and steam-sterilized at 250"F (1210C), 15 pounds per square inches (1.01 x 105 Pa) steam pressure for 7 hours. Each load is then cooled for 24 hours before seeding.

After the bags of substrate have been sterilized, they are preferably seeded under sterile conditions in laminar airflow hoods. Seeding is accomplished by introducing pure spawn or, preferably, colonized grain from previous production runs. Approximately 5 to 10 tablespoons (75 to 150 ml) of colonized grain is added into each 2-pound (0.91 Kg) bag. Each of the bags is then shaken to mix the colonized grain throughout the new unit.

This thorough mixing of the previously colonized grain with the substrate reduces the normal incubation time considerably. Thus, a 2-pound (0.91 Kg) bag will usually be fully colonized after approximately 3 weeks of incubation at 800F (26.60C). Usually 15 new 2-pound (0.91 Kg) units may be started from each colonized 2-pound (0.91 Kg) unit. The preferred size of bag is 8 pounds (3.6 Kg) because of the disproportionately greater number of buds per 8 pound (3.6 Kg) bag when compared with 2 pound (0.91 Kg) and 4 pound (1.8 Kg) bags.

After approximately 3 weeks, the grain substrate will be mostly or completely digested, leaving only the mycelium in the bag. The bag can be retained in the mycelial stage for approximately 3 to 4 months for shipment or storage. When mushroom production is desired, the bags containing the mycelium are subjected to a cold shock by chilling them at 40 to 650F (4.4 to 18.3 C)for 5 to 15 days under cool white fluorescent lighting of 25 to 100 lux. The preferred cold shock is at a temperature of 450F (7.20C) for 7 to 9 days, although a cold water bath for 24 to 48 hours also may be used.

The bags can be shipped in a refrigerated container during this cold shock stage.

As an alterative to the cold shock method of inducing fruiting, the msceli-=a may be removed from the bags and exposed to an intermittent cold water mist. it is preferred that the misting take place during daylight hours and also during a 2 hour period during the night the water used for misting is chilled to 50 to 750F (10 to 23.90c) and misting occurs for 2 to 120 seconds at 2 t: 10 minute intervals for 6 to 15 hours during the daylight period. Approximately 10 to 20 days after the mycelium is exposed to mist, shiitake mushrooms may be harvested. Subsequent crops from the bags may occur 20 to 30 days apart.

The relative humidity in the misting environment must be at least 80%.

As an alternative to the intermittent chilled water mist, the mycelium may be removed from the bags and allowed to fruit using previously known methods.

After the substrate has been spent, it may be used for other purposes, such as compost, animal feed, mushroom compost for other mushrooms or insect feed.

After formation of the mycelium, but before fruiting, the mycelium also may be used as animal feed or for human food. Useful biochemicals also may be extracted from the mycelium.

Although the foregoing invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it will ' be obvious that certain changes and modifications may be practiced within the scope of the invention, as described in the claims. For example, and not by way of limitation, the substrate described herein is suitable for growing many species of mushrooms, including those listed in Mushroom List 1, which is a part of this description and incorporated herein by reference, and many genera of fungi, including those listed in Fungal List 2, which is a part of this description and incorporated herein by reference. Many of these fungi are useful for their biochemical or other properties. Thus, the substrate can be used for growing penicillin mold, weed molds, yeasts and medicinal mushrooms.

Accordingly, no limitation is to be inferred except as set forth in the claims.

MUSHROOM LIST 1 Scientific Name Common Name Agaricus arvensis Horse Mushroom Agaricus augustus The Prince Agaricus bernardii Agaricus bisporus Agaricus bitorquis Agaricus campestris Common Field Mushroom Agaricus excellans Agaricus langei Agaricus macrosporus Agaricus silvaticus Agaricus silvicola Wood Mushroom Agaricus vaporarius Agrocybe aegerita Brown Swordbelt Armillaria Caligata Armillaria ponderosa Armillariella mellea Armillariella tabescens Auricularia polytricha Wood Ear Auricularia auricula Wood Ear Calvatia craniiformis Skull-shaped Puffball Calvatia gigantea Giant Puffball Clitocybe geotrapa Coorinus comatus Shaggy Inky Cap Dictyphora duplicata Netted Stinkhorn Flammulina velutipes Enoki Galerina mutabilis Ganoderma lucidum Reishi Grifola frondosa ~- Hen of the Woods Grifola umbellata Zhu Ling Hericium coralloides Pom Pom Hericium erinaceus Laetiporus sulphureus Sulfur Polypore Lentinus edodes Shiitake Lepiota naucina Smooth Lepiota Lepiota procera Parasol Mushroom Lepiota rachodes Scaly Lepiota Leoista nuda Wood Blewit Leucopaxillus giganteus Lycoperdon gemmatus Gem-Studded Puffball Lycoperdon pyriforme Pear-Shaped Puffball Lyophyllum cecastes Honshimeji Lyophyl lum ulmarium Macrolepiota procera Parasol Marasmius oreades Fairy Ring Morchella angusticeos Black Morel Morchella deliciosa Morchella esculenta White Morel Morchella conica Conical Morel Morchella crassipes Thick-Footed Morel Morchella elata Morchella semilibera Morchella vulgaris Common Morel Panellus serotinus Panus sp.

Pholiota adiposa Fat Pholiota Pholiota nameko Nameko Pleurotus columbinus Blue Oyster Pleurotus cornucopiae Canary Pleurotus cystidiosus Abalone Pleurotus eryngii Pleurotus flabellatus Pink Oyster Pleurotus florida Florida Oyster Pleurotus ostreatus Oyster Pleurotus pulmonarius Pleurotus sajor-caju Phoenix Pleurotus salmoned stramineus Sparassis crispa ~ Cauliflower Stropharia rugosoannulata Wine Red Stropharia Tremella fusciformis White Jelly Tricholomopsis rutflans Volvariella bakeril Volvariella bombycina Volvariella volvacea Paddy Straw FUNGAL LIST 2 List of Fungal Genera That Mav be Grown on the Substrate Abortiporus Amylostereum Absidia Anomoporia Achlya Antrodia Acremonium Apiotrichum Acrophialophora Arachnomyces Acrospeira Armillariella Actinomucor Arthrinium Agaricus Arthrobotrys Aggro cube Arthrographis Aleurodiscus Ascotricha Allescheria Ashbya Alternaria Aspergillus Alysidium Athelia Amanita Aureobasidium Amauroascus Auricularia Amylomyces Backusella Boletus Beauveria Bondarzewia Bispora Botryodiplodia Bjerkandera Botryotrichum Blakeslea Botrytis Blastomyces Bovista Boletopsis Byssochlamys Cadophora Coccospora Calbovista Cochliobolus Calcarisporium Colletotrichum Caldariomyces Collybia Calocera Co lumno cys tis Calocybe Conidiobolus Calonectria Coniella Calvatia Coniophora Camarops Coniothyrium Candida Conoplea Cantharellus Coprinus Celphalosporium Cordyceps Cephaliophora Coridus Cephaloascus Coriolus Ceratocystis Corticium Cercospora Cortinarius Cerinomyces Coryne Ceriosporopsis Corynespora Cerrena Coryneum Chaetomel la Craterellus Chaetomium Craterellus Chalara Crebrothecium Chalaropsis Cryphonectria Choanephora Cryptococcus Chondrostereum Cryptoporus Chroogomphus Cryptosporiopsis Chrysosporium Cunninghamella Circinella Curvularia Cladosportium Custingophora Clavariade lphus Cyanthus Claviceps Cylindrocarpon Clavicorona Cylindrocephalum Clavispora Cylindrocladium Clavulina Cystostereum Clitocybe Cytospora Clitopilus Cytospora Dacrymyces Dictyostelium Dacryopinax Diheterospora Dactylium Diplocarpon Daedalea Diplodia Debaryomyces Dips china Dekkera ~ Discula Dendryphion Ditiola Dentinum Doratomyces Dermaloma Dothistroma Dichomitus Drechslera Echinodontium Epicoccum Elsinoe Eupenicillium Emericella Eutypa Emericeilopsis Exophiala Entoloma Favolus Flammulina Femsjonia Fomes Filobasidium Fomitopsis Fistulina Fusarium Fla=nila Fuscoboletinus Ganoderma Gnomonia Geotrichum Gomphidius Gerlachia Gomphus Gibberella Grandinia Gilmaniella Graphium Gliocladium Grifola Gliomastrix Guepiniopsis Gloeophyllum Gymnopilus Gloeoporus Gyrodon Gloeosporium Gyromitra Glomerella Gyroporus Hanseniaspora Humicola Hansenula Humicolopsis Haploporous Hyal odendron Helicostylum Hydnum Helminthosporium Hygrophoropsis Helvella Hygrophorus Hendersonuia Hymenochaete Hericium Hyphopichia Heterobasidion Hypomyces Hirschioporus Hypomyces Hormodendrum Hypoxylon Incrustoporia - Irpex Inocybe Isaria Inonotus Ishnoderma Kloeckera Kluyveromyces Laccaria Lenzites Lactarius Leptosphaerulina Laetisaria Leucopaxillus Laurilia Libertella Leccinum Linderina Lentinellus Lipomyces Lentinula Lycoperdon Lentinus Lyophyl lum Lentodium Macrophomina Monads cuts Mammaria Monilinia Marasmiellus Monochaetia Marasmius Monodictus Melanconium Monosporium Melanoleuca Mortierella Memnoniella Mucor Meruliopsis Myceliophythora Merulius Mycena Merulius Mycocentrospora Metarrhizium Mycosphaerella Metschnikowia Myriococcum Micronectriella Myrothecium Mollisia Naematoloma Neurospora Nectria Nodulisporium Neocosmospora Nomuraea Odontia Oosporidium Oedocephalum Ophiostoma Oidiodendron Osmoporus Omphalotus Ostenia Onnia Oudemansiella Pachybasium Phyl loporus Pachysolen Physarum Paecilomyces Phytophthora Panellus Pichia Panus - Piptoporus Papularia Piricularia Papulaspora Pithomyces Pellicularia Pleurocybella Penicillium Pleurotus Peniophora Plicatura Perenniporia Pluteus Periconia Podospora Pestalotia Polyozellus Pestalotiopsis Polyporus Peziza Poria Phaeocoriolellus Potebniamyces Phaeolus Preussia Phanerochaete Psathyrella Phellinus Pseudeurotium Phialomyces Pseudofusarium Phialophora Pseudohydnum Phlebia Pseudospiropes Phlogiotis Ptychogaster Pholiota Pulcherricium Phoma Pycnoporus Phoma Pytenochaeta Phomopsis Pyrenophora Phycomyces Pythium Radulodon Rhizopus Ramaria Rhodosporidium Ramaricium Rhodotorula Resinicium Rigdoporus Retinocyclus Robillarda Rhinocladiella Rosellinia Rhizoctonia Russula Rhizomucor Saccharomyces Sphaceloma Saccharomycopsis Spicaria Sacodon Spiroidium Saprolengnia Spondylocladium Sarcosphaera Spongipellus Schizophyllum Sporidesmium Schizosaccharomyces Sporidiobolus Schwanniomyces Sporobolomyces Sclerotinia Sporothrix Sclerotium Sporotrichum Scolecobasidium Stachybotrys Scopulariopsis Staurophoma Scytalidium Steccherinum Scytinostroma Stemphylium Sebacina Stereum Sepedonium Stibella Septomyxa Strobilomyces Septoria Stromatinia Seroula Suillus Sirodesmium Syncephalastrum Sistotrema Syringospora Sordaria Talaromyces Tricellua Taphrina Trichocladium Termitomyces Trichoderma Tetracladium Tricholoma Thamnidium Tri chophyton Thamnostylum Trichosporon Thanatephorus Trichothecium Thermoascus Trichurus Thermomyces Tridentaria Thielavia Trigonops is Thielaviopsis Truncatella Torulaspora Tuber Torulopsis Tympanis Trametes Tyromyces Tremella Ulocladium Utilago Valsa Verticicladiella Valsaria Verticillium Vararia Volucrispora Verpa Volutella Wallemia Whetzelinia Wardomyces Xeromphalina ~ Xylobolus Xylaria xylogone Yarrowia Yeasts Zalerion Zygosaccharomyces Zygodesmus Zygosporium zygorhynchus Zythia Industrial Applicability.

The invention can be used for the inexpensive and efficient cultivation of fungi, especially shiitake.

Other fungi also may be cultivated, including fungi useful for food or medicinal purposes.

Claims (43)

1. A method for culturing mushrooms on a substantially cellulose free medium, comprising: preparing a substantially cellulose free grain mixture by mixing water in approximately one to one-fourth parts by weight per part of a dry mixture containing a major portion of grain; sterilizing said grain mixture to kill any microorganisms that may be present and to kill any spores that may be formed by said microorganisms; introducing mushroom spawn into said grain mixture; incubating said mushroom spawn to allow said mushroom spawn to consume said grain mixture and to form mycelium; inducing said mycelium to fruit, whereby mushroom fruiting bodies are formed; and harvesting said fruiting bodies.

2. A method according to claim 1, wherein said incubating step is carried out for between approximately three weeks and six months.

3. A method according to claim 1 or 2, wherein said incubating step is carried out for approximately three weeks.

4. A method according to any preceding claim, wherein said mushroom spawn comprises tree mushroom spawn.

5. A method according to claim 4, wherein said tree mushroom spawn comprises shiitake mushroom spawn.

6. A method according to claim 4, wherein said tree mushroom spawn is selected from the group consisting of oyster mushroom spawn, enoki mushroom spawn, wood ear mushroom spawn, white jelly mushroom spawn and pom pom mushroom spawn.

7 A method according to any preceding claim, wherein said sterilizing step comprises: boiling said grain mixture to kill any microorganisms that may be present and to induce creation of spores; inducing said spores to germinate; and sterilizing said grain mixture to kill said germinated spores.

8 A method according to any preceding claim, further comprising: mixing said mushroom spawn throughout said grain mixture.

9. A method according to any preceding claim, further comprising: adding minor portions of starch, protein and nutrient sources to said grain mixture.

10. A method for using a sterilized grain mixture, comprising: culturing tree mushroom fruiting bodies in said grain mixture, said sterilized grain mixture being free of spores.

11. A method according to claim 1O, wherein said culturing step comprises: inoculating tree mushroom spawn into said grain mixture; incubating said tree mushroom spawn to allow said tree mushroom spawn to consume said grain mixture and to form mycelium; and inducing said mycelium to form fruiting bodies.

12. A method according to claim 10, wherein said tree mushroom spawn comprises shiitake mushroom spawn.

13. A method according to claim 10, wherein said tree mushroom spawn is selected from the group consisting of oyster mushroom spawn, enoki mushroom spawn, wood ear mushroom spawn, white jelly mushroom spawn and pom pom mushroom spawn.

14. A method according to any of claims 10 to 13, wherein said culturing step comprises: introducing said grain mixture into a microorganism impermeable container; sterilizing said container and said grain mixture; inoculating tree mushroom spawn into said container; incubating said tree mushroom spawn in said grain mixture and said container to form mycelium; and inducing said mycelium to form tree mushroom fruiting bodies.

15. A method according to any of claims 10 to 14, wherein said grain mixture is prepared from an initial mixture comprising water in approximately one to one-fourth parts by weight per part of a dry mixture containing a major portion of grain; and wherein said initial mixture has been boiled for a sufficient time to kill any spore forming microorganisms, cooled for a sufficient time to allow any spores to germinate, and sterilized before said germinated spores have matured sufficiently to form new spores.

16. A method according to claim 15, wherein said boiling step is carried out for approximately 1 hour.

17. A method according to claim 15 or 16, wherein said cooling step is carried out for approximately 8 to 24 hours.

18. A method according to any of claims 15 to 17, wherein said sterilizing step is carried out by steam sterilizing said mixture.

19. A method according to any of claims 10 to 18, wherein said grain mixture comprises a major portion of grain and minor portions of starch, protein and nutrient sources.

20. A method according to claim 19, wherein said starch, protein and nutrient sources are preselected to meet nutritional requirements of tree mushrooms.

21. A method according to any of claims 10 to 20, further comprising mixing a permeability improving additive into said grain mixture

22. A method according to any of claims 1O to 21, wherein said grain mixture is essentially free of cellulose.

23. A method for culturing fungi, comprising: preparing a substantially cellulose free grain mixture comprising water in approximately one to onefourth parts by weight per part of a dry mixture comprising a major portion of grain; effecting removal of microorganisms and spores from said grain mixture; introducing said fungi into said grain mixture; incubating said fungi in said grain mixture to allow said fungi to consume said grain mixture; and harvesting said fungi.

24. A method according to claim 23, wherein said effecting step comprises: boiling said grain mixture to kill microorganisms and induce formation of spores; cooling said grain mixture to induce germination of said spores; sterilizing said grain mixture to kill said germinated spores.

25. A method for obtaining useful biochemicals, comprising: preparing a grain mixture by mixing water in approximately one to one-fourth parts by weight per part of a dry mixture containing a major portion of grain; sterilizing said grain mixture to kill any microorganisms that may be present and to kill any spores that may be formed by said microorganisms; introducing mushroom spawn into said grain mixture; incubating said mushroom spawn to allow said mushroom spawn to consume said grain mixture and to form mycelium; and extracting useful biochemicals from said mycelium.

26. A method according to claim 25, wherein said mushroom spawn comprises tree mushroom spawn.

27. A method according to claim 26, wherein said tree mushroom spawn comprises shiitake mushroom spawn.

28. A method according to claim 26, wherein said tree mushroom spawn is selected from the group consisting of oyster mushroom spawn, enoki mushroom spawn, wood ear mushroom spawn, white jelly mushroom spawn and pom pom mushroom spawn.

29. A method according to any of claims 25 to 28, wherein said sterilizing step comprises: boiling said grain mixture to kill any microorganisms that may be present and to induce creation of spores; inducing said spores to germinate; and sterilizing said grain mixture to kill said germinated spores.

30. A method for using a sterilized substantially cellulose free grain mixture comprising: culturing tree mushroom mycelia in said substantially cellulose free grain mixture without the use of a casing layer, said sterilized grain mixture being free of spores; and extracting useful biochemicals from said mycelia.

31. A method according to claim 30, wherein said culturing step comprises: inoculating tree mushroom spawn into said grain mixture; incubating said tree mushroom spawn to allow said tree mushroom spawn to consume said grain mixture and to form mycelium.

32. A method according to claim 31, wherein said tree mushroom spawn comprises shiitake mushroom spawn.

33. A method according to claim 31, wherein said tree mushroom spawn is selected from the group consisting of oyster mushroom spawn, enoki mushroom spawn, wood ear mushroom spawn, white jelly mushroom spawn and pom pom mushroom spawn.

34. A method according to any of claims 30 to 34, wherein said culturing step comprises: introducing said grain mixture into a microorganism impermeable container; sterilizing said container and said grain mixture; inoculating said tree mushroom spawn into said container; incubating said tree mushroom spawn in said grain mixture and said container to form mycelium; and extracting useful biochemicals from said mycelium.

35. A method according to any of claims 30 to 34, wherein said grain mixture is prepared from an initial mixture comprising water in approximately one to one-fourth parts by weight per part of a dry mixture containing a major portion of grain; and wherein said initial mixture has been boiled for a sufficient time to kill any spore forming microorganisms, cooled for a sufficient time to allow any spores to germinate, and sterilized before said germinated spores have matured sufficiently to form new spores.

36. A method according to claim 35, wherein said boiling step is carried out for approximately 1 hour.

37. A method according to claim 35 or 36, wherein said cooling step is carried out for approximately 8 to 24 hours.

38. A method according to any of claims 35 to 37, wherein said sterilizing step is carried out by steam sterilizing said mixture.

39. A method according to any of claims 30 to 38, wherein said grain mixture comprises a major portion of grain and minor portions of starch, protein and nutrient sources.

40. A method according to claim 39, wherein said starch, protein and nutrient sources are preselected to meet nutritional requirements of tree mushrooms.

41. A method according to any of claims 30 to 40, further comprising mixing a permeability improving additive into said grain mixture.

42. A method for obtaining useful biochemicals, comprising: preparing a substantially cellulose free grain mixture comprising water in approximately one to onefourth parts by weight per part of a dry mixture comprising a major portion of grain; effecting removal of microorganisms and spores from said grain mixture; introducing fungi into said grain mixture; incubating said fungi in said grain mixture to allow said fungi to consume said grain mixture and to form mycelium; and extracting useful biochemicals from said mycelium.

43. A method according to claim 42, wherein said effecting step comprises: boiling said grain mixture to kill microorganisms and induce formation of spores; cooling said grain mixture to induce germination of said spores; sterilizing said grain mixture to kill said germinated spores.