Method for reducing heavy metal content of edible mushrooms

Abstract

The invention discloses a method for reducing the heavy metal content of edible mushrooms, and belongs to the technical field of microorganisms and preparations thereof. According to the method provided by the invention, pesticide residues and heavy metal exceeding are fully controlled from the sources of a culture medium, soil covering, water and the like, and the quality of edible mushroom products is integrally improved; several common natural mineral substances and natural organic matter extraction materials are applied and are scientifically proportioned; heavy metals and part of pesticide residues are fixedly attached through flocculation, ion binding and filtering effects, so that the heavy metals and part of pesticide residues are prevented from being absorbed by the edible mushrooms, and the quality of the edible mushrooms is improved.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of microorganisms and their preparations, and particularly relates to a method for reducing the heavy metal content of edible fungi. BACKGROUND

[0002] In recent years, the output of edible fungi in China has increased rapidly, and the varieties have been increasing, but the product quality is often plagued by problems such as excessive agricultural residues and heavy metals. Due to the strong enrichment ability of edible fungi for certain metal elements in their biological nature, excessive heavy metals affect product quality, especially product export. In some areas, the original soil and water quality have excessive heavy metal content, and in some areas, mining and chemical enterprise pollution has caused soil, water, and air pollution, which is then absorbed by crops and trees, and the heavy metal content of straw, bran, and sawdust used for edible fungus cultivation is also excessive. The raw materials for edible fungus production medium, water, and soil cannot be separated, and the use of water is also inseparable from the use of water for fruiting and earing varieties. The heavy metals in the raw materials, water, and soil for edible fungus production medium can only be blocked, isolated, and not absorbed to fundamentally solve the problem of excessive heavy metals.

[0003] Therefore, how to develop a product and technical method to fully control excessive heavy metals from the source of medium, soil, and water, and to improve the overall quality of edible fungus products, has become an important issue to be solved. SUMMARY

[0004] In view of this, the purpose of the present application is to provide a method for reducing the heavy metal content of edible fungi, which fully controls excessive agricultural residues and heavy metals from the source of medium, soil, and water, and improves the overall quality of edible fungus products.

[0005] In order to achieve the above-mentioned purpose, the present application provides the following technical scheme: The present application provides a method for reducing the heavy metal content of edible fungi, comprising the following steps: S1, purifying edible fungus mixing and spraying water to obtain purified water; S2, adding medium additive according to 0.2% of the weight of the edible fungus medium, mixing uniformly, and using purified water to mix the material; for edible fungi that need to be covered with soil for fruiting, 15g / m 2 of soil additive is added to the soil and mixed uniformly, and then the soil is covered after adjusting the soil moisture with purified water.

[0006] Based on the above technical scheme, further, the purified water paving mat (5) is used for purifying the mixing and spraying water, and the purified water paving mat (5) is used for filtering the edible fungus mixing and spraying water to obtain purified water.

[0007] Based on the above technical scheme, further, the water purification paving mat (5) is composed of 10% of calcium-based bentonite particles (1) by weight, 30% of 30-50 mesh attapulgite particles (2), 30% of 30-50 mesh zeolite particles (3) and 30% of 30-50 mesh vermiculite particles (4) from top to bottom.

[0008] Based on the above technical scheme, further, the water purification paving mat (5) is shaped by a nylon mesh bag with a zipper opening at the top.

[0009] Based on the above technical scheme, further, the water purification paving mat (5) is used in an amount of 10-20 kg per square meter.

[0010] Among them, the amount of water purification paving mat is determined according to the specific circumstances of water quality, and the better the water quality, the smaller the amount.

[0011] Based on the above technical scheme, further, the culture medium additive is composed of 60% of 250-325 mesh calcium-based bentonite powder, 38% of 250-325 mesh attapulgite powder and 2% of chitosan by weight.

[0012] Based on the above technical scheme, further, the soil additive is composed of 50% of 250-325 mesh calcium-based bentonite powder, 28% of 250-325 mesh attapulgite powder, 20% of 30-50 mesh zeolite particles and 2% of chitosan by weight.

[0013] Compared with the prior art, the present application has the following beneficial effects: 1. The method provided by the present application fully controls heavy metal exceeding standard from the source of culture medium, soil covering and water, and improves the quality of edible fungus products as a whole.

[0014] 2. The method provided by the present application uses several common natural minerals and natural organic extraction materials, uses their respective fixation and attachment bias to different heavy metals, and uses scientific proportioning; through flocculation, ion combination and filtration, heavy metals and part of the agricultural residue components are fixed and attached, so as to block the absorption of heavy metals and part of the agricultural residue components by edible fungus, and improve the quality of edible fungus. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application, the drawings involved in the embodiments will be briefly introduced below.

[0016] Figure 1 The water purification process schematic diagram of the water purification paving mat of the present application embodiment 1; In the figure: 1, calcium bentonite particles; 2, attapulgite particles; 3, 30% of 30-50 mesh zeolite particles; 4, vermiculite particles; 5, clean water paving mat; 6, nylon mesh bag with zipper opening on the top; 7, water injection pipe; 8, automatic water stop device. DETAILED DESCRIPTION

[0017] The application will be described in detail below with examples, but the embodiments of the application are not limited thereto. Obviously, the examples described below are only some of the embodiments of the application, and other similar embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0018] Example 1 In this embodiment, the method provided by the application is used to perform the preparation work before the cultivation of edible fungi.

[0019] S1, purify the edible fungi mixing material and spraying water to obtain purified water; S2, after adding culture medium additives at 0.2% by weight of the culture medium, mix the culture medium, and use the purified water to mix the material; after adding soil covering additives according to the soil covering material required for each square meter of seeding area, mix the soil covering material, and use the purified water to mix the material.

[0020] The purified water is purified by the clean water paving mat 5, and the edible fungi mixing material and the spraying water are filtered by the clean water paving mat 5 to obtain the purified water.

[0021] The clean water paving mat 5 is composed of 10% by weight of calcium bentonite particles 1, 30% of 30 mesh attapulgite particles 2, 30% of 30 mesh zeolite particles 3, and 30% of 30 mesh vermiculite particles 4 from top to bottom.

[0022] The clean water paving mat 5 is shaped by a nylon mesh bag with a zipper opening on the top.

[0023] The amount of the clean water paving mat 5 is 10 kg per square meter.

[0024] The culture medium additives are composed of 60% by weight of 250 mesh calcium bentonite powder, 38% of 250 mesh attapulgite powder, and 2% of chitosan.

[0025] The soil covering additives are composed of 50% by weight of 250 mesh calcium bentonite powder, 28% of 250 mesh attapulgite powder, 20% of 30 mesh zeolite particles, and 2% of chitosan.

[0026] As Figure 1As shown, 10% of calcium-based bentonite particles 1, 30% of 30 mesh diatomite particles 2, 30% of 30 mesh zeolite particles 3 and 30% of 30 mesh vermiculite particles 4 are loaded into a nylon mesh bag 6 with a zipper opening at the top, and the zipper is pulled up; the water purification paving mat 5 is paved on the container bottom with the same paving mat plane, the bottom is a grid, water is poured into the container, and then the bottom spontaneously seeps purified clean water into the purified water container to obtain purified water.

[0027] Example 2 After preparation by the method of Example 1, edible mushroom planting is carried out, taking Auricularia auricula as the object, and the heavy metals of the obtained edible mushroom are investigated.

[0028] Auricularia auricula cultivation, culture medium: hard miscellaneous wood chips 66%, corn cob 20%, wheat bran 12%, gypsum powder 1%, lime powder about 0.8% (to make pH about 8), culture medium additive 0.2%. Add the purification water of the paving mat to the material according to the material-water ratio of 1:1.1. According to the conventional bagging, sterilization, inoculation and cultivation, the bag is opened after the mycelium is full, and the bag is cultivated in the ear shed. The mature ear pieces are harvested. After, through the third party organization SGS Dalian Branch detection, detection result lead, cadmium, mercury, arsenic, chromium, nickel 6 heavy metal indexes are not detected .

[0029] Example 3 After preparation by the method of Example 1, edible mushroom planting is carried out, taking Auricularia auricula as the object, and the heavy metals of the obtained edible mushroom are investigated.

[0030] Auricularia auricula cultivation, culture medium: hard miscellaneous wood chips 66%, corn cob 20%, wheat bran 12%, gypsum powder 1%, lime powder about 0.8% (to make pH about 8), culture medium additive 0.2%. Add the purification water of the paving mat to the material according to the material-water ratio of 1:1.1. According to the conventional bagging, sterilization, inoculation and cultivation, the bag is opened after the mycelium is full, and the bag is cultivated in the ear shed. The mature ear pieces are harvested. After, through the third party organization SGS Dalian Branch detection, detection result lead, cadmium, mercury, arsenic, chromium, nickel 6 heavy metal indexes are not detected .

[0031] Example 4 After preparation by the method of Example 1, edible mushroom planting is carried out, taking Auricularia auricula as the object, and the heavy metals of the obtained edible mushroom are investigated.

[0032] The cultivation medium of Hericium erinaceus is: 56.8% of hard miscellaneous sawdust, 30% of corn cob, 10% of wheat bran, 2% of soybean meal, and about 1% of gypsum powder (to make the pH about 8), and 0.2% of culture medium additive. The culture medium is mixed with the purified water according to the ratio of 1:1.1. The culture medium is sterilized, inoculated, and cultured according to the conventional method. After the mycelium fills the bag, the bag is opened, and the Hericium erinaceus is cultivated on the ground in the shed. The purified water is sprayed on the Hericium erinaceus. The mature Hericium erinaceus is harvested After, through the third party organization SGS Dalian Branch detection, detection result lead, cadmium, mercury, arsenic, chromium, nickel 6 heavy metal indexes are not detected .

[0033] Comparative Example 1 Example 2 is used as the experimental group. The culture medium additive is removed in the production of Auricularia auricula-judae in the comparative group. The water used for mixing and spraying is replaced with ordinary well water. The wood chips and corn cobs used in the experiment come from the surrounding soil of the Liaodong iron ore area, which has a high content of lead, cadmium, mercury, arsenic, chromium, and nickel. The results of the third-party detection institution show that the detection results of the Auricularia auricula-judae products in the experimental group do not contain 6 heavy metal indicators such as lead, cadmium, mercury, arsenic, chromium, and nickel. The heavy metal content of the Auricularia auricula-judae products in the comparative group is: lead 0.42 mg / kg, cadmium 0.48 mg / kg, mercury 0.15 mg / kg, arsenic 0.59 mg / kg, chromium 0.19 mg / kg, and nickel 0.45 mg / kg. According to the provisions of the “National Food Safety Standard Limit of Contaminants in Foods” (GB 2762-2022), the indicators of lead ≤0.3 mg / kg, cadmium ≤0.5 mg / kg, mercury ≤0.1 mg / kg, arsenic ≤0.5 mg / kg, chromium ≤0.2 mg / kg, and nickel ≤0.4 mg / kg, the lead, mercury, arsenic, and nickel are all over the standard. See Table 1 for details.

[0034] Comparative Example 2 Example 3 is used as the experimental group. The culture medium additive is removed in the production of Stropharia rugosoannulata in the comparative group. The soil additive is not added when covering the soil. The water used for mixing and spraying is replaced with ordinary well water. The wood chips, corn cobs, and corn straws used in the experiment come from the surrounding soil of the Liaodong iron ore area, which has a high content of lead, cadmium, mercury, arsenic, chromium, and nickel. The results of the third-party detection institution show that the detection results of the Stropharia rugosoannulata products in the experimental group do not contain 6 heavy metal indicators such as lead, cadmium, mercury, arsenic, chromium, and nickel. The heavy metal content of the Stropharia rugosoannulata products in the comparative group is: lead 0.45 mg / kg, cadmium 0.56 mg / kg, mercury 0.16 mg / kg, arsenic 0.62 mg / kg, chromium 0.16 mg / kg, and nickel 0.48 mg / kg. According to the provisions of the “National Food Safety Standard Limit of Contaminants in Foods” (GB 2762-2022), the indicators of lead ≤0.3 mg / kg, cadmium ≤0.5 mg / kg, mercury ≤0.1 mg / kg, arsenic ≤0.5 mg / kg, chromium 0.2 mg / kg, and nickel 0.4 mg / kg, the lead, cadmium, mercury, arsenic, and nickel are all over the standard.

[0035] Comparative Example 3 Example 2 as the experimental group, in the comparative example, respectively, remove the clean water paving mat, culture medium additives in the calcium bentonite, attapulgite, zeolite, vermiculite, chitosan components, for the cultivation of Stropharia rugosoannulata, and then the Stropharia rugosoannulata product is detected by a third party testing institution, and the results are shown in Table 1.

[0036] According to Table 1, it is concluded that the components such as calcium bentonite, attapulgite, zeolite, vermiculite and chitosan in the water-soaking paving mat and the culture medium additive have certain differences in the adsorption and fixation capacity of different heavy metals, and the effect can be best under the synergistic action of the reasonable collocation of the concentrated substances. The optimal addition amount of each additive in the clean water paving mat, the culture medium and the soil covering still has further experimental optimization space.

[0037] Table 1: Change of heavy metal content in Auricularia auricular product (mg / kg) with different additive components.

[0038]

[0039] Example 5 The difference between this example and Example 1 is that: The clean water paving mat 5 is composed of 10% calcium bentonite particles 1, 30% 50-mesh attapulgite particles 2, 30% 50-mesh zeolite particles 3 and 30% 50-mesh vermiculite particles 4 by weight percentage from top to bottom.

[0040] The amount of the clean water paving mat 5 is 20 kg per square meter.

[0041] The culture medium additive is composed of 60% 325-mesh calcium bentonite powder, 38% 325-mesh attapulgite powder and 2% chitosan by weight percentage.

[0042] The soil covering additive is composed of 50% 325-mesh calcium bentonite powder, 28% 325-mesh attapulgite powder, 20% 50-mesh zeolite particles and 2% chitosan by weight percentage.

[0043] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for reducing the heavy metal content of edible mushrooms, characterized in that, It comprises the following steps: S1, edible fungi mixed material and spraying water are purified to obtain purified water; S2, 0.2% of the medium additives are added according to the weight of the edible fungus culture medium, and then mixed uniformly, and purified water is used for mixing; for edible fungi that need to be covered with soil, 15g / m 2 of the covering soil additives are added to the covering soil and mixed uniformly, and then the covering soil is covered after adjusting the moisture content of the covering soil with purified water.

2. The method for reducing the heavy metal content of edible mushrooms according to claim 1, characterized in that, The mixed material and the spraying water are purified by the water purification paving mat (5), and the edible fungi mixed material and the spraying water are filtered by the water purification paving mat (5) to obtain the purified water.

3. The method for reducing the heavy metal content of edible mushrooms according to claim 2, characterized in that, The water purification paving mat (5) is composed of 10% calcium-based bentonite particles (1), 30% 30-50 mesh attapulgite particles (2), 30% 30-50 mesh zeolite particles (3) and 30% 30-50 mesh vermiculite particles (4) in terms of weight percentage from top to bottom.

4. The method for reducing the heavy metal content of edible mushrooms according to claim 2, characterized in that, The water purification paving mat (5) is shaped by a nylon mesh bag with a zipper opening at the top.

5. The method for reducing the heavy metal content of edible mushrooms according to claim 2, characterized in that, The water purification paving mat (5) is used in an amount of 10-20 kg per square meter.

6. The method of claim 1, wherein the edible mushroom is selected from the group consisting of shiitake mushroom, oyster mushroom, and button mushroom. The culture medium additive is composed of 60% 250-325 mesh calcium-based bentonite powder, 38% 250-325 mesh attapulgite powder and 2% chitosan in terms of weight percentage.

7. The method of claim 1, wherein the edible mushroom is selected from the group consisting of shiitake mushroom, oyster mushroom, and button mushroom. The soil covering additive is composed of 50% 250-325 mesh calcium-based bentonite powder, 28% 250-325 mesh attapulgite powder, 20% 30-50 mesh zeolite particles and 2% chitosan in terms of weight percentage.

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