Method for preparing food-grade glassine paper from mycelia of edible fungi by liquid fermentation and food-grade glassine paper

Abstract

The present invention discloses a method for preparing food-grade glassine paper from edible mushroom liquid fermentation mycelium and the food-grade glassine paper, which relates to a method for preparing glassine paper using natural biological materials. The preparation method of the food-grade glassine paper is as follows: Step 1: Preparation of the base paper of edible mushroom liquid fermentation mycelium; Step 2: Preparation of the surface paper of edible mushroom liquid fermentation mycelium; Step 3: Preparation of the food-grade glassine paper. The present invention prepares the food-grade glassine paper from edible mushroom liquid fermentation mycelium, which can replace the traditional papermaking method mainly using wood as the raw material, without adding plastics and chemical coating agents, and has the advantages of environmental protection, low carbon and degradability. It is a food-grade oil-proof, moisture-proof and semi-transparent glassine paper, and has broad application prospects in various fields such as food, medicine and express labels.

Description

Technical Field

[0001] The present invention relates to a method for preparing glassine paper using natural biological materials, and particularly to a method for preparing food-grade glassine paper from edible mushroom liquid fermentation mycelium and the food-grade glassine paper. Background Art

[0002] Glassine paper, also known as translucent glass paper, is a high-density wood pulp paper that has been subjected to special treatments such as sizing and silicone oil coating. It has excellent oil and moisture resistance properties and good transparency, and is mainly used as the release paper, high-speed automatic label paper, special tape, and double-sided tape substrate in the food and pharmaceutical fields.

[0003] In recent years, the demand for special papers such as glassine paper in China has been continuously increasing. The label papers made of glassine paper are widely used in retail consumer goods, durable consumer goods, as well as logistics, anti-counterfeiting and other fields. However, the large-scale use of label papers will lead to serious consumption of natural resources.

[0004] In addition, the waste generated after the use of label papers has also become a difficult problem in environmental governance today. In China, label papers made of coated and laminated paper are widely used due to their price advantages. The coated and laminated paper contains components such as plastic films and synthetic adhesives. These components are difficult to degrade in the natural environment and accumulate over time, which will eventually hinder the air permeability and water permeability of the soil and even pollute the groundwater. At the same time, the recycling of label papers is also very difficult. It is necessary to separate different materials such as the surface material, glue, and base paper. The whole process is complex and costly, and the recycling efficiency is extremely low. Therefore, it is imperative to use natural biological materials to replace wood and develop food-grade glassine paper with low cost, environmental protection, degradability, and wide application.

[0005] In nature, as decomposers, fungi, together with eukaryotes such as plants and animals, maintain the ecological balance. Among fungi, there are approximately 2,000 known edible fungi for humans. The mycelium is the main body of edible fungi. Different from the fruiting bodies growing on the ground, the mycelium grows underground and is composed of long filamentous substances. In recent years, edible fungi have been widely used in the fields of food, medicine, and industrial materials due to their rich nutrition, remarkable efficacy, and superior performance. However, the yield of wild edible fungi is small and difficult to obtain, and the cultivation cycle of artificially cultivated edible fungi is very long. For example, the artificial cultivation cycle of Ganoderma lucidum, a precious edible fungus in China, exceeds 6 months, which not only increases the cultivation cost of edible fungi but also limits their application as industrial materials. As a perfect substitute for edible fungi, the mycelium not only contains almost the same nutritional value as edible fungi but also has good strength and toughness, showing good application potential in the manufacture of various industrial products. Compared with the fruiting body, the cultivation cycle of the mycelium is short, generally only about 10 days. Therefore, the production cost is greatly reduced, and the application prospect as an industrial material is broadened. Using the excellent material properties of the mycelium to prepare glassine paper greatly reduces the consumption of forests by the paper industry. Summary of the Invention

[0006] The present invention provides a method for preparing food-grade glassine paper from edible mushroom liquid-fermented mycelium and food-grade glassine paper. It aims to solve the problems of excessive consumption of forest resources during the manufacture of glassine paper, difficult treatment of environmental pollution caused by the waste after the use of glassine paper, and difficult recycling.

[0007] According to one aspect of the present invention, there is provided a method for preparing food-grade glassine paper from edible mushroom liquid-fermented mycelium, and the method comprises the following steps:

[0008] Step 1: Preparation of the base paper of edible mushroom liquid-fermented mycelium;

[0009] Using edible mushroom liquid-fermented mycelium and sodium hydroxide solution, alkali-treated edible mushroom liquid-fermented mycelium is prepared. The alkali-treated edible mushroom liquid-fermented mycelium is steamed in a steaming box, and then the steamed alkali-treated edible mushroom liquid-fermented mycelium is placed in pure water to obtain an aqueous dispersion of edible mushroom liquid-fermented mycelium. The aqueous dispersion of edible mushroom liquid-fermented mycelium is homogenized to obtain a mycelium suspension. The mycelium suspension is centrifuged and the precipitate is retained. The precipitate is vacuum filtered to obtain a mycelium filter cake. The filter cake is placed in a mold and dried to obtain the base paper of edible mushroom liquid-fermented mycelium;

[0010] Step 2: Preparation of the surface paper of edible mushroom liquid-fermented mycelium;

[0011] Step 2.1: Preparation of antioxidant food gum;

[0012] Waxy corn starch and pure water are formulated into a starch solution, and then catechins are added to obtain an antioxidant food gum;

[0013] Step 2.2: Coating;

[0014] The antioxidant food gum is coated on both sides of the edible mushroom liquid fermentation mycelium base paper to obtain an edible mushroom liquid fermentation mycelium surface paper;

[0015] Step 3: Preparation of food-grade glassine paper;

[0016] Step 3.1: Preparation of edible mushroom liquid fermentation mycelium Pickering nanoemulsion;

[0017] Edible mushroom liquid fermentation mycelium and pure water are taken to prepare edible mushroom liquid fermentation mycelium powder, which is emulsified to obtain edible mushroom liquid fermentation mycelium Pickering nanoemulsion;

[0018] Step 3.2: Coating;

[0019] The edible mushroom liquid fermentation mycelium Pickering nanoemulsion is coated on both sides of the edible mushroom liquid fermentation mycelium surface paper to obtain food-grade glassine paper.

[0020] Preferably, in step 1, the specific operation method for preparing alkali-treated edible mushroom liquid fermentation mycelium with edible mushroom liquid fermentation mycelium and sodium hydroxide solution is: take edible mushroom liquid fermentation mycelium, add a sodium hydroxide solution with a mass concentration of 0.001%, and make the ratio of the mass of edible mushroom liquid fermentation mycelium to the volume of the sodium hydroxide solution with a mass concentration of 0.001% be: 10 g / ml. After stirring evenly, alkali-treated edible mushroom liquid fermentation mycelium is obtained; the steaming method is: lay the alkali-treated edible mushroom liquid fermentation mycelium flat in a mold, place it in a 100 °C steamer, and steam for 10 - 30 min.

[0021] Preferably, in step 1, the specific method for placing the steamed alkali-treated edible mushroom liquid fermentation mycelium in pure water to obtain an edible mushroom liquid fermentation mycelium aqueous dispersion is: take the steamed alkali-treated edible mushroom liquid fermentation mycelium, rinse it with pure water 2 - 3 times and then place it in pure water to obtain an edible mushroom liquid fermentation mycelium aqueous dispersion with a mass concentration of 20 - 60 g / 100 mL.

[0022] Preferably, in step 1, the specific method for homogenizing the aqueous dispersion of edible mushroom liquid-fermented mycelium to obtain a mycelium suspension is as follows: Homogenize the aqueous dispersion of edible mushroom liquid-fermented mycelium with a high-speed homogenizer for 10 - 30 min at 8500 - 10000 r / min to obtain mycelium suspension A. Place mycelium suspension A on a temperature-controlled magnetic stirrer, and add a citric acid solution dropwise thereto so that the concentration of citric acid in mycelium suspension A reaches 0.1 - 0.5 g / 100 mL. React at a temperature of 100 - 150 °C and a rotation speed of 200 - 400 r / min for 10 - 40 min to obtain mycelium suspension B. Then stop heating, and perform magnetic stirring on mycelium suspension B at a rotation speed of 200 - 400 r / min until it cools to room temperature to obtain mycelium suspension C.

[0023] Preferably, the specific method for centrifuging the mycelium suspension and retaining the precipitate is as follows: Place mycelium suspension C in a centrifuge, centrifuge at 4000 - 5500 r / min for 10 - 20 min, recover the supernatant, and retain the precipitate. The precipitate is mycelium precipitate A. Wash mycelium precipitate A with pure water and place it in a centrifuge for centrifugation. Repeat the above steps 2 - 3 times, and retain the precipitate. The precipitate is mycelium precipitate B. The specific method for subjecting the precipitate to vacuum filtration to obtain a mycelium filter cake is as follows: Place mycelium precipitate B in a vacuum filter, keep the vacuum degree at -0.09 - -0.06 MPa, and perform vacuum filtration for 15 - 30 min to obtain a mycelium filter cake.

[0024] Preferably, in step 1, the specific method for placing the filter cake in a rectangular mold and air-drying it to obtain the base paper of edible mushroom liquid-fermented mycelium is as follows: Place the mycelium filter cake in a rectangular mold with a width of 10 cm and a length of 15 cm, and use a leveling knife to level the surface of the mycelium filter cake so that the thickness of the mycelium filter cake in the rectangular mold is uniform. The density of the mycelium filter cake in the rectangular mold is 0.6 - 1.6 g / cm 3 ; Place the mycelium filter cake at room temperature for 10 - 12 h and air-dry it naturally to obtain the base paper of edible mushroom liquid-fermented mycelium.

[0025] Preferably, after step 1, the method further includes: Through apparent observation, screening the base paper of edible mushroom liquid-fermented mycelium without wrinkles, holes, and spots; Through actual measurement, screening the base paper of edible mushroom liquid-fermented mycelium with a thickness deviation of not more than ±6% and a tightness of not less than 0.7 g / cm 3 ; Through a paper tearing strength tester, screening the base paper of edible mushroom liquid-fermented mycelium with a transverse tearing degree of not less than 180 mN; Through the constant speed stretching method, screening the base paper of edible mushroom liquid-fermented mycelium with a longitudinal tensile strength of not less than 3 kN / m and a transverse tensile strength of not less than 1.3 kN / m; Through the hot and cold cycle environmental temperature test method, screening the base paper of edible mushroom liquid-fermented mycelium without deformation within the temperature range of -20 - 60 °C.

[0026] Preferably, in step 2, the specific method for preparing the antioxidant food gum is as follows: Prepare a suspension of waxy corn starch in pure water with a mass concentration of 3 - 5 g / 100 mL, place it in a boiling water bath and heat for 45 - 95 min, stop heating, and wait for the temperature to drop to 85 - 95 °C to obtain a starch solution. Add catechin to the starch solution so that the mass concentration of catechin in the starch solution reaches 0.3 - 0.6 g / 100 mL. Use a uniform speed stirrer to stir at 200 - 600 r / min for 10 - 30 min, and then cool to room temperature to obtain the antioxidant food gum.

[0027] Preferably, in step 2, the specific method for preparing the edible mushroom liquid fermentation mycelium face paper is as follows: On both sides of the edible mushroom liquid fermentation mycelium base paper, use a coater to evenly coat the antioxidant food gum respectively, with a single-sided coating thickness of 20 - 50 μm, and then place it in a blast drying oven and dry it at 40 - 60 °C for 10 - 30 min to obtain the edible mushroom liquid fermentation mycelium face paper.

[0028] Preferably, after step 2, the method further includes: Through visual observation, screen for the edible mushroom liquid fermentation mycelium face paper without bubbles and defects on the surface; Through antioxidant testing, screen for the edible mushroom liquid fermentation mycelium face paper with an oxidation radical scavenging rate exceeding 90%; Through a reflectance photometer, screen for the edible mushroom liquid fermentation mycelium face paper with a transparency not less than 47%; Use a contact angle measuring instrument to screen for the edible mushroom liquid fermentation mycelium face paper with a water phase contact angle range of 70 - 90°.

[0029] Preferably, the specific method for preparing the edible mushroom liquid fermentation mycelium Pickering nanoemulsion in step 3 is as follows: The specific method for preparing the edible mushroom liquid fermentation mycelium Pickering nanoemulsion is as follows: Take the edible mushroom liquid fermentation mycelium and disperse it in pure water to obtain an aqueous dispersion of the edible mushroom liquid fermentation mycelium with a mass concentration of 40%, and place it in a planetary ball mill, set the rotation speed at 300 - 600 r / min, and carry out grinding treatment for 2 - 4 h. Place the ground aqueous dispersion of the edible mushroom liquid fermentation mycelium in a vacuum freeze dryer and dry it at -70 °C for 4 - 12 h to obtain the edible mushroom liquid fermentation mycelium powder; Take pure water, and successively add the edible mushroom liquid fermentation mycelium powder and beeswax to obtain a mixed solution, so that the mass concentration of the edible mushroom liquid fermentation mycelium powder in pure water is 0.5 - 1.5 g / 100 mL, and the volume ratio of beeswax to pure water is 2:3 - 3:2. Use a high-speed emulsifier to emulsify the above mixed solution at 45 - 75 °C and emulsify it at 20000 - 30000 r / min for 2 - 6 min to form the edible mushroom liquid fermentation mycelium Pickering nanoemulsion.

[0030] Preferably, in step 3, the specific method for preparing the food-grade glassine paper is as follows: Using a coater, evenly coat the Pickering nanoemulsion of edible mushroom liquid fermentation mycelium on both sides of the edible mushroom liquid fermentation mycelium surface paper, with a coating thickness of 10-30 μm; Place the edible mushroom liquid fermentation mycelium surface paper coated with the Pickering nanoemulsion of edible mushroom liquid fermentation mycelium in a forced-air drying oven and conduct drying treatment at 35-55°C for 10-30 minutes to obtain the food-grade glassine paper.

[0031] Preferably, after step 3, the method further includes: Using a reflectance photometer, screening for food-grade glassine paper with a transparency of not less than 42%; Using a smoothness tester, screening for food-grade glassine paper with a smoothness of not less than 1000 s; Using a roughness meter, screening for food-grade glassine paper with a roughness of not exceeding 1.8 μm; Using a contact angle measuring instrument, screening for food-grade glassine paper with an aqueous contact angle of not less than 80° and an oil-phase contact angle of not less than 45°; Using an oil absorbency measurement method, screening for food-grade glassine paper with an oil absorbency of not exceeding 1 g / m 2 ; Through the constant-speed stretching method, screening for food-grade glassine paper with a longitudinal tensile strength of not less than 3.6 kN / m and a transverse tensile strength of not less than 1.8 kN / m; Using a glossiness tester, screening for food-grade glassine paper with a glossiness of not less than 40 GU at a measurement angle of 75°; Through printer testing, screening for clear and distinguishable information such as text and barcodes printed on the food-grade glassine paper and that can be accurately read by scanning devices; Using a color difference meter, screening for a font color deviation of not more than 5 when printing on the surface of the food-grade glassine paper.

[0032] According to another aspect of the present invention, there is also provided a food-grade glassine paper.

[0033] The beneficial effects of the present invention: The method for preparing a food-grade glassine paper using edible mushroom liquid fermentation mycelium provided by the present invention will replace the traditional method mainly using wood, plastic film, chemical coatings, and chemical adhesives, without the need to cut down forests and not relying on raw logs. The method for preparing food-grade glassine paper using edible mushroom liquid fermentation mycelium; Using food-grade raw materials, without adding any chemical raw materials such as bleaching agents and fluorescent agents, non-toxic to the human body and environmentally friendly. The prepared food-grade glassine paper has good transparency, smoothness, oil resistance, and tensile strength, etc., and is suitable for use as express logistics labels, product labels, anti-counterfeiting labels, and food and pharmaceutical packaging papers, and has great application potential in many fields such as commercial retail, logistics, and warehousing. Description of the Drawings

[0034] Figure 1 It is a specific implementation flowchart of the present invention;

[0035] Figure 2 It is a morphological diagram of Ganoderma lucidum liquid fermentation mycelium;

[0036] Figure 3 It is the molecular structure diagram of Ganoderma lucidum liquid fermentation mycelium cross-linked by citric acid;

[0037] Figure 4 It is the microscopic structure diagram of the Ganoderma lucidum liquid fermentation mycelium filter cake;

[0038] Figure 5 It is the microscopic structure diagram of the ground Ganoderma lucidum liquid fermentation mycelium;

[0039] Figure 6 It is the apparent diagram of the antioxidant food gum. Among them, A: the content of egcg in the antioxidant food gum is 0; B: the content of egcg in the antioxidant food gum is about 5%; C: the content of egcg in the antioxidant food gum is about 10%; D: the content of egcg in the antioxidant food gum is about 15%; E: the content of egcg in the antioxidant food gum is about 20%;

[0040] Figure 7 It is the Pickering nanoemulsion morphology of the edible mushroom liquid fermentation mycelium;

[0041] Figure 8 It is the schematic diagram of the food-grade glassine paper. Among them, A is the flat food-grade glassine paper; B is the stacked food-grade glassine paper. Specific embodiments

[0042] In order to enable those skilled in the art to better understand the solution of this application, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this application. It should be noted that, without conflict, the embodiments in this application and the features in the embodiments can be combined with each other.

[0043] Secondly, the so-called "one embodiment" or "embodiment" herein refers to a specific feature, structure or characteristic that can be included in at least one implementation manner of the present invention. The "in one embodiment" that appears in different places in this specification does not all refer to the same embodiment, nor is it a separate or selectively exclusive embodiment from other embodiments.

[0044] In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or are inherent to these processes, methods, products or devices.

[0045] Example 1 of the present invention:

[0046] Refer to Figures 1-8 as shown.

[0047] The mycelium of edible fungi by liquid fermentation is the mycelium obtained from edible fungi. The edible fungi in the present invention include Agaricus bisporus, Tricholoma matsutake in the family Agaricaceae of the order Agaricales, Lentinula edodes, Flammulina velutipes in the family Tricholomataceae, Schizophyllum commune in the family Schizophyllaceae, Pleurotus nebrodensis, Pleurotus eryngii in the family Pleurotaceae, Auricularia auricula-judae in the family Auriculariaceae of the order Auriculariales, Tremella fuciformis in the family Tremellaceae of the order Tremellales, Fistulina hepatica, Hericium erinaceus in the family Polyporaceae of the order Polyporales, Phellinus igniarius in the family Hymenochaetaceae, Ganoderma lucidum in the family Ganodermataceae, Armillaria mellea in the genus Armillaria of the family Tricholomataceae, Agrocybe aegerita in the genus Agrocybe of the family Bolbitiaceae, Morchella esculenta in the genus Morchella of the family Morchellaceae, etc. Taking the edible fungus Ganoderma lucidum as an example, the application of Ganoderma lucidum mycelium by liquid fermentation in the preparation process of food-grade glassine paper is described.

[0048] Step 1: Preparation of the base paper of mycelium of edible fungi by liquid fermentation;

[0049] The mycelium of Ganoderma lucidum by liquid fermentation is white and paste-like, as Figure 2 shown; take 150 g of the mycelium of Ganoderma lucidum by liquid fermentation, add 15 mL of a sodium hydroxide solution with a mass concentration of 0.001%, stir evenly to obtain the alkali-treated mycelium of Ganoderma lucidum by liquid fermentation, spread the alkali-treated mycelium of Ganoderma lucidum by liquid fermentation in a rectangular flat porcelain dish, place it in a steamer at 100 °C, steam for 20 min, take 120 g of the steamed alkali-treated mycelium of Ganoderma lucidum by liquid fermentation from the rectangular flat porcelain dish, rinse it with pure water 2 - 3 times and then place it in 300 mL of pure water to obtain a water dispersion of the mycelium of Ganoderma lucidum by liquid fermentation, so that its mass concentration reaches 40 g / 100 mL, use a high-speed homogenizer to homogenize the water dispersion of the mycelium of Ganoderma lucidum by liquid fermentation at 9000 r / min for 20 min to obtain a mycelium suspension A; place the mycelium suspension A on a temperature-controlled magnetic stirrer, drop 15 mL of a citric acid solution into the mycelium suspension A so that the concentration of citric acid in the mycelium suspension A reaches 0.3 g / 100 mL, and react at a temperature of 120 °C and a rotation speed of 300 r / min for 30 min to obtain a mycelium suspension B, then stop heating and perform magnetic stirring on the mycelium suspension B at a rotation speed of 300 r / min until it cools to room temperature to obtain a mycelium suspension C; after the reaction is completed, place the mycelium suspension C in a centrifuge and centrifuge at 5000 r / min for 15 min, recover the supernatant, and retain the precipitate, the precipitate is: mycelium precipitate A; rinse the mycelium precipitate A with pure water and place it in a centrifuge for centrifugation, repeat the above steps 2 - 3 times, retain the precipitate, the precipitate is: mycelium precipitate B; place the mycelium precipitate B in a vacuum filter, keep the vacuum degree at -0.07 MPa, and filter for 20 min to obtain a mycelium filter cake, and the microstructure of the mycelium filter cake is as Figure 4As shown in the figure; place the mycelium filter cake in a rectangular flat-bottomed porcelain dish with a width of 10 cm and a length of 15 cm, and use a leveling knife to level the surface of the mycelium filter cake so that the thickness of the mycelium filter cake in the rectangular flat-bottomed porcelain dish is uniform. The density of the mycelium filter cake in the rectangular flat-bottomed porcelain dish is 1.0 g / cm 3 ; Place the mycelium filter cake at room temperature for 12 h and let it dry naturally to obtain the bottom paper of edible mushroom liquid-fermented mycelium. The molecular structure diagram of citric acid-crosslinked Ganoderma lucidum liquid-fermented mycelium is as shown in Figure 3 the figure;

[0050] Through apparent observation, select the bottom paper of edible mushroom liquid-fermented mycelium without wrinkles, holes and spots; through the actual measurement method, select the bottom paper of edible mushroom liquid-fermented mycelium with a thickness deviation not exceeding ±6% and a tightness not less than 0.7 g / cm 3 ; Through a paper tearing strength tester, select the bottom paper of edible mushroom liquid-fermented mycelium with a transverse tearing degree not less than 180 mN; through the constant speed stretching method, select the bottom paper of edible mushroom liquid-fermented mycelium with a longitudinal tensile strength not lower than 3 kN / m and a transverse tensile strength not lower than 1.3 kN / m; through the hot and cold cycle environmental temperature test method, select the bottom paper of edible mushroom liquid-fermented mycelium that does not deform within the temperature range of -20 to 60 °C.

[0051] All raw materials used in the present invention are food grade.

[0052] Edible mushrooms refer to edible macrofungi, including three parts: mycelium, fruiting body and spores. The edible mushrooms in the present invention include Agaricus bisporus, Tricholoma matsutake in the family Agaricaceae of the order Agaricales, Lentinula edodes, Flammulina velutipes in the family Tricholomataceae, Schizophyllum commune in the family Schizophyllaceae, Pleurotus nebrodensis, Pleurotus eryngii in the family Pleurotaceae, Auricularia auricula in the family Auriculariaceae of the order Auriculariales, Tremella fuciformis in the family Tremellaceae of the order Tremellales, Fistulina hepatica, Hericium erinaceus in the family Polyporaceae of the order Polyporales, Sanghuangporus sanghuang in the family Hymenochaetaceae, Ganoderma lucidum in the family Ganodermataceae, Armillaria mellea in the genus Armillaria of the family Tricholomataceae, Agrocybe aegerita in the genus Agrocybe of the family Bolbitiaceae, Morchella esculenta in the genus Morchella of the family Morchellaceae, etc.

[0053] The above embodiments are the preferred embodiments of the present invention, but are not limited to the above embodiments, and are applicable to edible mushrooms such as Lentinula edodes, Volvariella volvacea, Agaricus bisporus, Auricularia auricula, Tremella fuciformis, Hericium erinaceus, Dictyophora indusiata, Tricholoma matsutake, Tricholoma mongolicum, Russula vinosa, Ganoderma lucidum, Cordyceps sinensis, Tuber melanosporum, Pleurotus nebrodensis and Boletus edulis. Any changes, substitutions, combinations, etc. made without departing from the principle of the present invention are included in the protection scope of the present invention.

[0054] The edible mushrooms and the liquid-fermented mycelium of edible mushrooms used in the present invention are publicly available through conventional channels and are not limited to a specific liquid-fermented mycelium of edible mushrooms.

[0055] The citric acid used in the present invention is a green and non-toxic food-grade raw material, which can be used as a cross-linking agent to cross-link the processed edible mushroom liquid fermentation mycelium, helping the edible mushroom liquid fermentation mycelium to form a network structure. During the natural drying process of the mycelium filter cake, the edible mushroom liquid fermentation mycelium network becomes denser. After making the edible mushroom liquid fermentation mycelium base paper, it helps to improve the tightness, tear resistance and tensile strength of the paper.

[0056] Step 2: Preparation of the edible mushroom liquid fermentation mycelium top paper;

[0057] Step 2.1: Preparation of the antioxidant food gum;

[0058] Dissolve 12 g of waxy corn starch in 300 mL of pure water to prepare a suspension with a mass concentration of 4 g / 100 mL, place it in a boiling water bath and heat for 70 min, stop heating, and wait until the temperature drops to 90 °C to obtain a starch solution. Add 1.2 g of catechin to the starch solution so that the mass concentration of catechin in the starch solution reaches 0.4 g / 100 mL. Use a uniform speed stirrer to stir at 400 r / min for 20 min, and then cool to room temperature to obtain the antioxidant food gum;

[0059] The waxy corn starch used in the present invention is a type of glucose-based polymer with a branched starch content of more than 95%. Its molecular weight varies, the degree of polymerization is between 600 and 6000, and the degree of polymerization of the side chain is between 20 and 25. Starch granules are composed of amylose and amylopectin molecules arranged radially, with an alternating structure of crystalline regions and amorphous regions. Waxy corn starch granules are composed of highly branched molecules arranged radially. Compared with ordinary varieties of starch, the crystalline regions of waxy corn starch granules are arranged loosely and not tightly, making it easier for hot air, moisture, etc. to enter the interior of the microcrystalline bundles, reducing the intermolecular oxygen bond binding force, changing the structure of the starch crystalline region. After heat-moisture treatment, the starch granules will swell, rupture, and starch molecules flow out, occurring a starch gelatinization reaction, which promotes the increase of the system viscosity;

[0060] Catechin is epigallocatechin gallate (EGCG), that is: Figure 6 The EGCG in. After adding the natural antioxidant catechin, since catechin also contains a large number of hydroxyl groups, it can form hydrogen bonds with the hydroxyl groups of waxy starch molecules, playing a bridging role in waxy starch molecules, promoting the formation of a network structure of starch molecules, resulting in a further increase in the system viscosity. After the temperature drops to room temperature, a food gum with antioxidant function is formed;

[0061] Step 2.2: Coating;

[0062] On both sides of the edible mushroom liquid fermentation mycelium base paper obtained in Step 1, the antioxidant food gum obtained in Step 2.1 is evenly coated using a coater. The single-sided coating thickness is 40 μm, and then it is placed in a forced-air drying oven and dried at 50 °C for 20 min to obtain the edible mushroom liquid fermentation mycelium surface paper;

[0063] Through visual observation, select the edible mushroom liquid fermentation mycelium surface paper without bubbles and defects on the surface; through antioxidant testing, select the edible mushroom liquid fermentation mycelium surface paper with an oxidation radical scavenging rate exceeding 90%; through a reflectance photometer, select the edible mushroom liquid fermentation mycelium surface paper with a transparency of not less than 47%; use a contact angle measuring instrument to select the edible mushroom liquid fermentation mycelium surface paper with an aqueous contact angle range of 70-90°;

[0064] In the present invention, by evenly coating the antioxidant food gum on the edible mushroom liquid fermentation mycelium base paper, it is possible to fill the fine pores on the surface of the edible mushroom liquid fermentation mycelium base paper, improve the smoothness of the edible mushroom liquid fermentation mycelium base paper, endow the edible mushroom liquid fermentation mycelium base paper with good hydrophobicity, enhance the antioxidant and antibacterial properties of the edible mushroom liquid fermentation mycelium base paper, and make it suitable as paper for food and pharmaceuticals.

[0065] Step 3: Preparation of food-grade glassine paper;

[0066] Step 3.1: Preparation of edible mushroom liquid fermentation mycelium Pickering nanoemulsion;

[0067] Take 120 g of Ganoderma lucidum liquid fermentation mycelium and disperse it in 300 ml of pure water to obtain an aqueous dispersion of Ganoderma lucidum liquid fermentation mycelium with a mass concentration of 40%. Place it in a planetary ball mill, set the rotation speed at 400 r / min, and carry out grinding treatment for 3 h. After grinding, the microstructure of Ganoderma lucidum liquid fermentation mycelium in the aqueous dispersion of Ganoderma lucidum liquid fermentation mycelium is as Figure 5 shown; place the ground aqueous dispersion of Ganoderma lucidum liquid fermentation mycelium in a vacuum freeze dryer and carry out drying treatment at -70 °C for 8 h to obtain Ganoderma lucidum liquid fermentation mycelium powder; take 120 mL of pure water, and successively add 6 g of Ganoderma lucidum liquid fermentation mycelium powder and 80 mL of beeswax, so that the mass concentration of Ganoderma lucidum liquid fermentation mycelium powder in pure water is 0.5 g / 100 mL, and the volume ratio of beeswax to pure water is 2:3. Use a high-speed emulsifier to carry out emulsification treatment on the above mixture at 60 °C and emulsify it at 25000 r / min for 4 min to form an edible mushroom liquid fermentation mycelium Pickering nanoemulsion;

[0068] In the preparation of food-grade glassine paper, using the mycelium powder of edible fungi liquid fermentation as a Pickering emulsifier, through emulsification treatment, a Pickering nanoemulsion of edible fungi liquid fermentation mycelium with beeswax as the dispersed phase is formed. Uniformly coating it on the surface paper of edible fungi liquid fermentation mycelium helps to improve the gloss of the surface paper and enhance its oil resistance;

[0069] Step 3.2: Coating;

[0070] Using a coater, uniformly coat the Pickering nanoemulsion of edible fungi liquid fermentation mycelium on both sides of the surface paper of edible fungi liquid fermentation mycelium obtained in Step 2.2, with a coating thickness of 20 μm; Place the surface paper of edible fungi liquid fermentation mycelium coated with the Pickering nanoemulsion of edible fungi liquid fermentation mycelium in a forced-air drying oven and conduct drying treatment at 45 °C for 20 min to obtain food-grade glassine paper;

[0071] Using a reflectance photometer, screen for food-grade glassine paper with a transparency of not less than 42%; Using a smoothness tester, screen for food-grade glassine paper with a smoothness of not less than 1000 s; Using a roughness meter, screen for food-grade glassine paper with a roughness of not exceeding 1.8 μm; Using a contact angle measuring instrument, screen for food-grade glassine paper with an aqueous contact angle of not less than 80° and an oil-phase contact angle of not less than 45°; Using an oil absorbency measurement method, screen for food-grade glassine paper with an oil absorbency of not exceeding 1 g / m 2 ; Using the constant-speed stretching method, screen for food-grade glassine paper with a longitudinal tensile strength of not less than 3.6 kN / m and a transverse tensile strength of not less than 1.8 kN / m; Using a glossiness tester, screen for food-grade glassine paper with a glossiness of not less than 40 GU at a measurement angle of 75°; Through printer testing, screen for clear and distinguishable information such as text and barcodes printed on food-grade glassine paper and can be accurately read by scanning devices; Using a color difference meter, screen for a font color deviation of not more than 5 when printing on the surface of food-grade glassine paper.

[0072] Example 2 of the present invention:

[0073] The main difference from Example 1 is that when preparing the Pickering nanoemulsion of edible fungi liquid fermentation mycelium, the mycelium powder of Ganoderma lucidum liquid fermentation is dispersed in pure water at a concentration of 1 g / 100 mL, and the other operation steps are the same as those in Example 1.

[0074] Example 3 of the present invention:

[0075] The main difference from Example 1 is that when preparing the Pickering nanoemulsion of edible fungi liquid fermentation mycelium, the mycelium powder of Ganoderma lucidum liquid fermentation is dispersed in pure water at a concentration of 1.5 g / 100 mL, and the other operation steps are the same as those in Example 1.

[0076] Comparative Example 1:

[0077] The main difference from Example 1 is that when preparing the Pickering nanoemulsion of edible mushroom liquid fermentation mycelium, the powder of Ganoderma lucidum liquid fermentation mycelium was not added, and the other operation steps were the same as those in Example 1.

[0078] The Pickering nanoemulsions of edible mushroom liquid fermentation mycelium prepared from Examples 1-3 and Comparative Example 1 are as Figure 7 shown. Figure 7 From left to right in it are: Comparative Example 1: The powder of Ganoderma lucidum liquid fermentation mycelium was not added; Example 1: The powder of Ganoderma lucidum liquid fermentation mycelium was dispersed in pure water at a concentration of 0.5 g / 100 mL; Example 2: The powder of Ganoderma lucidum liquid fermentation mycelium was dispersed in pure water at a concentration of 1 g / 100 mL; Example 3: The powder of Ganoderma lucidum liquid fermentation mycelium was dispersed in pure water at a concentration of 1.5 g / 100 mL.

[0079] The parameters of the food-grade glassine paper prepared from Examples 1-3 and Comparative Example 1 are shown in Table 1.

[0080] Table 1 Parameters of the food-grade glassine paper prepared from Examples 1-3 and Comparative Example 1.

[0081]

[0082] Experimental Example 1:

[0083] The difference from Example 1 is only that when preparing the antioxidant food gum: catechin was not added to the starch solution. Therefore, the catechin content in the antioxidant food gum is 0, and the other operation steps are the same.

[0084] Experimental Example 2:

[0085] The difference from Example 1 is only that when preparing the antioxidant food gum: catechin was added to the starch solution to make the mass concentration of catechin in the starch solution reach 0.2 g / 100 mL. Therefore, the catechin content in the antioxidant food gum is about 5%, and the other operation steps are the same.

[0086] Experimental Example 3:

[0087] The difference from Example 1 is only that when preparing the antioxidant food gum: catechin was added to the starch solution to make the mass concentration of catechin in the starch solution reach 0.4 g / 100 mL. Therefore, the catechin content in the antioxidant food gum is about 10%, and the other operation steps are the same.

[0088] Experimental Example 4:

[0089] The difference from Example 1 is only that when preparing the antioxidant food gum: catechin was added to the starch solution to make the mass concentration of catechin in the starch solution reach 0.6 g / 100 mL. Therefore, the catechin content in the antioxidant food gum is about 15%, and the other operation steps are the same.

[0090] Experimental Example 5:

[0091] It is only different from Example 1 in the preparation of the antioxidant food gum: catechin is added to the starch solution so that the mass concentration of catechin in the starch solution reaches 0.8 g / 100 mL. Therefore, the catechin content in the antioxidant food gum is about 20%, and the other operation steps are the same.

[0092] The parameters of the food-grade glassine paper prepared from Experimental Examples 1-5 are shown in Table 2.

[0093] Table 2 Parameters of the food-grade glassine paper prepared from Experimental Examples 1-5.

[0094]

[0095] Preparation method of Ganoderma lucidum liquid fermentation mycelium in Experimental Example 6:

[0096] (1) Selection of strains:

[0097] Select high-quality, highly active, and genetically stable Ganoderma lucidum strains, such as Ganoderma lucidum and Ganoderma sinense (the Ganoderma lucidum strain used in this invention is Ganoderma lucidum), and prepare for liquid fermentation.

[0098] (2) Preparation of slant medium and strain activation:

[0099] Slant medium formula: 200 g of potato (peeled and cut into pieces, boiled for juice), 20 g of glucose, 20 g of agar, 1000 mL of water.

[0100] Mix the formula raw materials evenly, place them in an autoclave, and sterilize at 121 °C for 1 h. Then, wait for the medium to cool to about 42 °C, and pour it into glass test tubes under sterile conditions. After cooling to room temperature, make a slant medium. Inoculate the Ganoderma lucidum strain onto the slant medium and culture it at 28 °C for 7 days. White Ganoderma lucidum mycelia can be seen germinating and growing.

[0101] (3) Preparation of seed medium and strain culture:

[0102] Seed medium formula: 25 g of glucose, 15 g of peptone, 7 g of yeast extract, 2 g of potassium dihydrogen phosphate, 1 g of magnesium sulfate, 1000 mL of water.

[0103] Mix the formula raw materials evenly, pour them into a 300 mL Erlenmeyer flask, and then place them in an autoclave and sterilize at 121 °C for 1 h. Then, wait for the medium to cool to room temperature, and under sterile conditions, use an inoculation spatula to pick 4 mycelial blocks with a diameter of 0.5 cm from the slant medium strain and place them in the Erlenmeyer flask containing the seed medium.

[0104] Place the inoculated Erlenmeyer flask on a shaker and culture it by shaking at 28°C and 200 r / min for 7 days to allow the mycelium to grow and reproduce sufficiently, forming a Ganoderma lucidum liquid fermentation mycelium suspension.

[0105] (4)Centrifuge to obtain Ganoderma lucidum liquid fermentation mycelium:

[0106] Transfer the Ganoderma lucidum liquid fermentation mycelium suspension to a centrifuge tube and centrifuge at 4000 r / min for 20 min to precipitate the Ganoderma lucidum liquid fermentation mycelium at the bottom of the centrifuge tube, and recover the supernatant. Wash the precipitated Ganoderma lucidum liquid fermentation mycelium 3 times with ultrapure water to obtain pure Ganoderma lucidum liquid fermentation mycelium.

[0107] After the above implementation steps, a food-grade glassine paper prepared from Ganoderma lucidum liquid fermentation mycelium can be obtained, as Figure 8 shown.

[0108] The steps in the method of the embodiment of the present invention can be adjusted, combined, and deleted according to actual needs. In the solution of the present invention, the descriptions of each embodiment have their own emphases. For parts not detailed or recorded in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. The technical features of the technical solution of the present invention can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in the present invention.

[0109] The above is only the preferred embodiment of the present application. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present application, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present application.

Claims

1. A method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium, characterized in that: Edible fungi refer to edible mushrooms, and the method comprises the following steps: Step 1: using edible fungus liquid fermentation mycelium and sodium hydroxide solution to prepare alkali-treated edible fungus liquid fermentation mycelium, and placing the alkali-treated edible fungus liquid fermentation mycelium in a steamer for steaming, and then placing the steamed alkali-treated edible fungus liquid fermentation mycelium in pure water to obtain edible fungus liquid fermentation mycelium water dispersion, homogenizing the edible fungus liquid fermentation mycelium water dispersion and adding citric acid solution to obtain mycelium suspension, centrifuging the mycelium suspension and retaining the precipitate, vacuum filtering the precipitate to obtain mycelium filter cake, placing the filter cake in a mold, and drying it to obtain edible fungus liquid fermentation mycelium base paper; Step 2: waxy corn starch and purified water are prepared into starch liquid, and catechins are added to obtain antioxidant food glue; the antioxidant food glue is applied on both sides of the edible fungus liquid fermentation mycelium base paper to obtain the edible fungus liquid fermentation mycelium face paper; Step 3: freeze-dry edible fungus liquid fermentation mycelium and purified water to prepare edible fungus liquid fermentation mycelium powder, add beeswax and emulsify it to obtain edible fungus liquid fermentation mycelium Pickering nanoemulsion; apply edible fungus liquid fermentation mycelium Pickering nanoemulsion on both sides of edible fungus liquid fermentation mycelium facial paper to obtain food-grade glassine paper.

2. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 1, characterized in that: The specific operation method of using edible fungus liquid fermentation mycelium and sodium hydroxide solution to prepare alkali-treated edible fungus liquid fermentation mycelium is as follows: taking edible fungus liquid fermentation mycelium, adding sodium hydroxide solution with a mass concentration of 0.001%, so that the ratio of the mass of edible fungus liquid fermentation mycelium to the volume of sodium hydroxide solution with a mass concentration of 0.001% is: 10g / ml, and after stirring evenly, alkali-treated edible fungus liquid fermentation mycelium is obtained; the steaming method is as follows: spreading the alkali-treated edible fungus liquid fermentation mycelium in a mold, placing it in a 100°C steamer, and steaming it for 10 to 30 minutes.

3. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 2, characterized in that: The specific method of placing the steamed alkali-treated edible fungus liquid fermentation mycelium in pure water to obtain the edible fungus liquid fermentation mycelium aqueous dispersion is: taking the steamed alkali-treated edible fungus liquid fermentation mycelium, rinsing it with pure water 2-3 times and then placing it in pure water to obtain the edible fungus liquid fermentation mycelium aqueous dispersion with a mass concentration of 20-60g / 100mL.

4. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium as claimed in claim 3, characterized in that: The specific method for homogenizing the edible fungus liquid fermentation mycelium water dispersion to obtain the mycelium suspension is as follows: homogenizing the edible fungus liquid fermentation mycelium water dispersion with a high-speed homogenizer for 10 to 30 minutes at 8500 to 10000 r / min to obtain mycelium suspension A, placing the mycelium suspension A on a temperature-controlled magnetic stirrer, dripping citric acid solution thereto to make the concentration of citric acid in the mycelium suspension A reach 0.1 to 0.5 g / 100 mL, reacting for 10 to 40 minutes at a temperature of 100 to 150° C. and a rotation speed of 200 to 400 r / min to obtain mycelium suspension B, then stopping heating, and magnetically stirring the mycelium suspension B at a rotation speed of 200 to 400 r / min until it is cooled to room temperature to obtain mycelium suspension C.

5. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 4, characterized in that: The specific method of centrifuging the mycelium suspension and retaining the precipitate is: placing the mycelium suspension C in a centrifuge, centrifuging at 4000-5500 r / min for 10-20 minutes, recovering the supernatant, retaining the precipitate, and the precipitate is: mycelium precipitate A; rinsing the mycelium precipitate A with pure water and placing it in a centrifuge for centrifugation, repeating the above steps 2-3 times, retaining the precipitate, and the precipitate is: mycelium precipitate B; the specific method of vacuum filtering the precipitate to obtain the mycelium filter cake is: placing the mycelium precipitate B in a vacuum filter, maintaining the vacuum degree at -0.09-0.06MPa, filtering for 15-30 minutes, and obtaining the mycelium filter cake.

6. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium as claimed in claim 5, characterized in that: The specific method of placing the filter cake in a mold and drying it to obtain the edible fungus liquid fermentation mycelium base paper is as follows: placing the mycelium filter cake in a rectangular mold with a width of 10 cm and a length of 15 cm, using a spatula to smooth the surface of the mycelium filter cake so that the thickness of the mycelium filter cake in the rectangular mold is uniform, and the density of the mycelium filter cake in the rectangular mold is 0.6-1.6 g / cm 3 ; Place the mycelium filter cake at room temperature for 10 to 12 hours, dry it naturally, and obtain the edible fungus liquid fermentation mycelium base paper.

7. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium as claimed in claim 6, characterized in that: The specific method for preparing the antioxidant food glue is as follows: waxy corn starch is prepared into a suspension with a mass concentration of 3-5 g / 100 mL with purified water, placed in a boiling water bath and heated for 45-95 min, heating is stopped, and the temperature is reduced to 85-95° C. to obtain a starch solution, catechin is added to the starch solution to make the mass concentration of catechin in the starch solution reach 0.3-0.6 g / 100 mL, a uniform speed mixer is used to stir for 10-30 min at 200-600 r / min, and then cooled to room temperature to obtain the antioxidant food glue.

8. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 7, characterized in that: The specific method for preparing the edible fungus liquid fermentation mycelium facial paper is as follows: using a coating machine to evenly coat the two sides of the edible fungus liquid fermentation mycelium base paper with antioxidant food glue, with a single-side coating thickness of 20 to 50 μm, and then placing it in a blast drying oven at 40 to 60° C. for 10 to 30 minutes to obtain the edible fungus liquid fermentation mycelium facial paper.

9. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 8, characterized in that: The specific method for preparing the edible fungus liquid fermentation mycelium Pickering nanoemulsion is as follows: taking edible fungus liquid fermentation mycelium and dispersing it in pure water to obtain an aqueous dispersion of edible fungus liquid fermentation mycelium with a mass concentration of 40%, placing it in a planetary ball mill, setting the rotation speed to 300-600r / min, and grinding it for 2-4h, placing the ground edible fungus liquid fermentation mycelium aqueous dispersion in a vacuum freeze dryer, and drying it at -70°C for 4-12h to obtain the edible fungus liquid fermentation mycelium aqueous dispersion. Fermented mycelium powder; taking purified water, successively adding edible fungus liquid fermented mycelium powder and beeswax to obtain a mixed solution, wherein the mass concentration of the edible fungus liquid fermented mycelium powder in purified water is 0.5-1.5 g / 100 mL, and the volume ratio of beeswax to purified water is 2:3-3:2; using a high-speed emulsifier, at 45-75° C., the mixed solution is emulsified at 20000-30000 r / min for 2-6 min to form edible fungus liquid fermented mycelium Pickering nanoemulsion.

10. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 9, characterized in that: The specific method for preparing the food-grade glassine paper is as follows: using a coating machine, uniformly coating edible fungus liquid fermentation mycelium Pickering nanoemulsion on both sides of the edible fungus liquid fermentation mycelium facial paper, with a coating thickness of 10 to 30 μm; placing the edible fungus liquid fermentation mycelium facial paper coated with edible fungus liquid fermentation mycelium Pickering nanoemulsion in a blast drying oven, and performing drying treatment at 35 to 55° C. for 10 to 30 minutes to obtain the food-grade glassine paper.

11. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 10, characterized in that: The edible fungus liquid fermentation mycelium base paper is screened to have no wrinkles, holes and spots; through the actual measurement method, the thickness deviation of the edible fungus liquid fermentation mycelium base paper is screened to be no more than ±6% and the tightness is no less than 0.7g / cm 3 ; Through the paper tear strength tester, the edible fungus liquid fermentation mycelium base paper is screened to have a transverse tear strength of not less than 180mN; through the constant speed stretching method, the longitudinal tensile strength of the edible fungus liquid fermentation mycelium base paper is screened to be not less than 3kN / m, and the transverse tensile strength is not less than 1.3kN / m; through the hot and cold cycle environmental temperature test method, the edible fungus liquid fermentation mycelium base paper is screened to not deform within the temperature range of -20 to 60°C.

12. The method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium according to claim 11, characterized in that: The edible fungus liquid fermented mycelium facial paper screened has no bubbles and defects on its surface; through antioxidant test, the edible fungus liquid fermented mycelium facial paper screened has an oxidative free radical scavenging rate of more than 90%; through reflectance photometer, the edible fungus liquid fermented mycelium facial paper screened has a transparency of not less than 47%; using a contact angle measuring instrument, the water phase contact angle range of the edible fungus liquid fermented mycelium facial paper screened is 70 to 90°.

13. A food-grade glassine paper prepared from edible fungus liquid fermentation mycelium, characterized in that: The food-grade glassine paper is prepared by the method for preparing food-grade glassine paper from edible fungus liquid fermentation mycelium as claimed in any one of claims 1 to 12.

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