CN116158381B

CN116158381B - Method for purifying harmful substances in green crab body of hairy crab

Info

Publication number: CN116158381B
Application number: CN202211542632.1A
Authority: CN
Inventors: 花勃
Original assignee: Xinxihui Ecological Technology Qingdao Co ltd
Current assignee: Xinxihui Ecological Technology Qingdao Co ltd
Priority date: 2022-12-03
Filing date: 2022-12-03
Publication date: 2023-09-19
Anticipated expiration: 2042-12-03
Also published as: CN116158381A

Abstract

The application relates to the technical field of cultivation, and particularly discloses a method for purifying harmful substances in hairy crab green crabs, which comprises the following steps: selecting green crabs; purifying and culturing: one crab is placed in an independent culture room, the culture water which flows circularly at room temperature is utilized for culture, the temperature of the culture water is reduced to 0 ℃ at the speed of less than or equal to 2 ℃/d, the salinity is increased to 5-20 millat the speed of less than or equal to 2 mill/d, and purified culture is completed, in the culture process, the ammonia nitrogen content of the culture water is less than 0.1mg/L, the salt content is less than 0.01mg/L, the pH value is 7.5-8.4, the dissolved oxygen content is 8-10ppm, and the feed is fed once a day in the morning and evening. The method for purifying harmful substances in the green crab body of the hairy crab has the advantages of effectively removing heavy metals, pesticide residues, antibiotics and other harmful substances in the green crab body, improving the edible safety of the green crab, increasing the weight of crab cream and improving the color formation of the crab cream.

Description

Method for purifying harmful substances in green crab body of hairy crab

Technical Field

The application relates to the technical field of cultivation, in particular to a method for purifying harmful substances in green crabs of hairy crabs.

Background

The hairy crab, the academic name Eriocheir sinensis, also called river crab, is a wild hole crustacean with migration, is born in sea water, grows into fresh water after growing into young crabs, is delicious in meat taste and rich in nutrition, and is a food widely accepted by Chinese and overseas people. Crabs are generally mated at 10-15 ℃, spawn in sea and fresh water intersection water areas to generate flea-shaped bodies, the flea-shaped bodies of the crabs pass through the large-eye bodies, the young crabs and the young crabs in a proper ecological environment, the crab species are evolved into finished crabs, the crabs are a general term of the crabs before and after sexual maturity, the crabs comprise yellow crabs and green crabs, the yellow crabs are further reproduction molted, the crab shells are changed into dark green crabs, the green crabs are the sexual mature crabs, and the green crabs are generally caught and marketed.

After more than 30 years of development, crab farming has become one of the most viable and potential industries for development in fishery production in China. Compared with lake cultivation, pond cultivation has the advantages of convenient management, short cultivation period, high commodity crab recapture rate and the like, but is limited by cultivation water bodies and fragile ecological environment, and under the current 'high-feeding and high-density' cultivation mode, the pond water quality is seriously deteriorated, and a large amount of toxins are enriched in water. The toxin sources in the crab pond are exogenous and endogenous, and the exogenous toxin is mainly derived from drug residues of farmers, for example, pyrethrin, ivermectin, copper sulfate and other drugs are excessively used in pond cleaning, disinsection and moss killing. The endogenous toxins are mainly derived from toxic substances generated by transformation of water microorganisms, algae and the like of residual baits, medicines, dead waterweeds and the like, particularly in a high-temperature period in summer, a large amount of residual baits and feces are generated along with the increase of the feed intake of river crabs, in addition, waterweeds such as the waterweeds are influenced by high water temperature, a large amount of rotten roots die, and the factors often lead to the overproof of ammonia nitrogen, nitrite and hydrogen sulfide content in the water. In order to regulate water quality and prevent crab diseases, farmers generally adopt methods of applying a large amount of antibiotics, sterilizing and disinfecting drugs, improving bottom drugs and the like, which are easy to cause that green crabs on the market carry pesticide residues or harmful substances such as antibiotics, in addition, the crabs have the capability of accumulating heavy metals, the heavy metals in the crabs can be out of standard when growing in water in polluted environment, and when eating the crabs with the out-of-standard heavy metals, the heavy metals in the crabs can be transferred into the body and then combined with DNA, RNA and proteins of human bodies, so that the immune function of the human bodies is disordered, and cells cannot be metabolized normally.

Aiming at the related technology, the inventor finds that the hairy crab green crabs are not purified by heavy metals, pesticide residues, antibiotics and other harmful substances before being on the market, and the hairy crab green crabs are easy to cause harm such as allergy, poisoning and the like to human bodies after being eaten by the human bodies.

Disclosure of Invention

In order to purify heavy metals, pesticide residues and antibiotics in the hairy crab green crabs and improve the edible safety of the crabs, the application provides a method for purifying harmful substances in the hairy crab green crabs.

In a first aspect, the application provides a method for purifying harmful substances in a hairy crab green crab body, which adopts the following technical scheme:

a method for purifying harmful substances in a hairy crab green crab body comprises the following steps:

selecting green crabs: selecting green crabs with complete and strong body shape, no disease or injury, lively and active and regular specifications;

purifying and culturing: one crab is placed in an independent culture room, the culture water which flows circularly at room temperature is utilized for culture, the temperature of the culture water is reduced to 0 ℃ at the speed of less than or equal to 2 ℃/d, the salinity is increased to 5-20 millat the speed of less than or equal to 2 mill/d, and purified culture is completed, in the culture process, the ammonia nitrogen content of the culture water is less than 0.1mg/L, the salt content is less than 0.01mg/L, the pH value is 7.5-8.4, the dissolved oxygen content is 8-10ppm, and the feed is fed once a day in the morning and evening.

By adopting the technical scheme, the green crabs are firstly adapted to cultivation in the cultivation water with the room temperature and the salinity of 0, then the temperature is gradually reduced, the salinity is increased, the migration environment of the green crabs is simulated, the crab paste is enabled to be plump and thick, the whole purification cultivation process lasts for about 10 days, the contents of ammonia nitrogen, salt and dissolved oxygen in the cultivation process are controlled, and the pH value is maintained within a certain range. The circulating aquaculture water can promote the discharge of impurities in the cheeks and intestinal tracts of crabs under the dual stimulation of temperature reduction and higher salinity, and metabolize harmful substances such as pesticide residues, heavy metals, antibiotics and the like in the bodies, so that the cheeks of the crabs are clean and white, no fishy smell of soil is generated, the crab spawns and the crab cream are more mature than the common fresh water hairy crabs, the meat quality is more delicious, the crab spawns and the crab cream are more Q-shaped, the gonads are promoted, namely the crab spawns and the crab cream are mature when the flavor of the hairy crabs is maintained, the cleaning is not needed, the maturity is improved, and therefore, the purification and detoxification of the pesticide residues, the heavy metals and the antibiotics in the bodies of the crabs are reduced, and the edible safety is improved.

Preferably, the temperature of the water for cultivation is reduced to 0 ℃ at a rate of 1-1.5 ℃/d, and the salinity is increased to 20%o at a rate of 1-2%o/d.

By adopting the technical scheme, the hairy crabs can adapt to the temperature and the salinity of the water for cultivation by using proper cooling speed and salt rising speed.

Optionally, the feed comprises cooked corn kernels or wheat kernels.

By adopting the technical scheme, the cooked corn kernels and the wheat kernels are used as feed, so that the feed can be prevented from polluting water quality, and the feed is beneficial to ingestion, digestion and absorption of crabs, after the corn kernels and the wheat kernels are cooked at high temperature, cells lose bioactivity, a carbon-water mixture in the corn kernels is converted into monosaccharide, fructose and sucrose which are beneficial to the absorption of crabs, and the corn kernels or the vitamins contained in the wheat kernels are partially destroyed at high temperature and lose effect, so that the cooked corn kernels or the wheat kernels are beneficial to the absorption and utilization of nutrition by a crab digestive system.

Optionally, the feed is prepared by the following method:

(1) Mixing cooked corn kernels or wheat kernels with water and lime powder uniformly, soaking for 8-10h, and fishing out;

(2) Decocting radix astragali and rhizoma Acori Graminei with water for 1-2 hr, filtering, and collecting filtrate;

(3) Steaming Bulbus Allii, herba Gynostemmatis and sweet potato, and mashing into paste;

(4) Mixing the product obtained in the step (1) with the filtrate obtained in the step (2), adding the product obtained in the step (3), mixing with astaxanthin, extruding, granulating, balling and drying.

By adopting the technical scheme, after the corn kernels or the wheat kernels are cooked, lime powder is used for preventing the corn kernels or the corn kernels from rotting, and after the corn kernels or the wheat kernels are soaked, the corn kernels and the wheat kernels are softer, so that the green crabs can eat the green crabs conveniently; decocting radix astragali and rhizoma Acori Graminei, collecting filtrate, steaming Bulbus Allii, herba Euphorbiae Humifusae and rhizoma Dioscoreae, mashing into paste, mixing the above obtained materials, mixing with astaxanthin, extruding, granulating, making into spheres with particle size of 0.5-2mm, drying, and making spheres softer under water for intake of green crab when the fodder is put into cultivation room; the astragalus membranaceus can enhance the immunity of green crabs, promote the metabolism of the green crabs, help to perfect the immune mechanism in vivo, build a stronger immune barrier, promote the disease resistance of the green crabs, and in addition, the grassleaf sweelflag rhizome and the gynura segetum can sterilize and purify water, so that the survival condition of the crabs can be improved; the astaxanthin is adopted to promote the development of crab gonads and provide oxidation resistance, and in addition, the vitamin B6-containing sweet potato is matched, so that gonad maturation can be promoted, crab paste is full, astragalus mongholicus, garlic and the like are added, more comprehensive nutrition is provided for green crabs, the consolidation of the crab paste is facilitated, the content of various heavy metals such as lead, zinc and mercury in the bodies of the green crabs can be reduced by the garlic, the health and safety of feed sources are ensured, the resistance and the survival rate are improved, the appetite of the green crabs can be promoted by using poria cocos, grassleaf sweelflag rhizome and the like, the digestion, absorption and anabolism are enhanced, the feed utilization rate is improved, the drug residues, pesticide residues and heavy metal discharge of the green crabs are promoted, and the cleanliness of the cheeks of the green crabs is improved.

Optionally, the feed comprises the following raw materials in parts by weight: 10-20 parts of cooked corn kernels or wheat kernels, 3-6 parts of poria cocos, 1-3 parts of astragalus membranaceus, 2-4 parts of rhizoma acori graminei, 1-4 parts of garlic, 4-7 parts of gynura segeti, 1-3 parts of sweet potato and 3-8 parts of astaxanthin.

By adopting the technical scheme, the cooked corn kernels or wheat kernels are used as main raw materials of the feed, the corn kernels and the wheat kernels are not peeled, when the corn kernels and the wheat kernels are extruded, the corn kernels and the wheat kernels can be used as binders to bind other components together to form spheres, and the spheres are not easy to be dispersed in water for cultivation to pollute the water quality.

Optionally, the daily feed amount of the feed is 3-10% of the weight of the green crabs, preferably 8%.

By adopting the technical scheme, the feed is fed according to the weight of the crab, so that the feed utilization rate is high, too much feed can not be left, the water quality is influenced, the metabolism speed in the crab is influenced, and the discharge of harmful substances such as heavy metals, antibiotics and the like is slowed down.

Optionally, the water for cultivation is recycled after biological purification, physical filtration and ultraviolet disinfection in sequence.

Through adopting above-mentioned technical scheme, can have impurity such as certain fodder residue or crab's excrement in the aquaculture water of usefulness, if direct cyclic utilization, along with the decomposition of incomplete bait or excrement, can lead to ammonia nitrogen too high, the crab carries the toxin, has reduced edible security, still can lead to the immunity and the resistance of crab to drop, the intake reduces, and the easy disease takes place, long-term use contains fodder residue or contains the aquaculture water of crab excrement, can lead to ammonia nitrogen to exceed standard, causes the crab to poison and die.

Optionally, the depth of the culture water in the culture room is such that the green crabs are immersed in the culture water.

By adopting the technical scheme, the crabs can float up and down in the water for cultivation, and the crabs can float out of the water surface, so that the crabs can move conveniently.

Optionally, the transparency of the water for cultivation in the cultivation room is maintained at 40-60cm, preferably 50cm.

By adopting the technical scheme, the transparency of the water in the breeding room is always maintained at 40-60cm, the clean and thorough breeding water is suitable for the survival of crabs, and the clean and transparent water has no pathogenic organisms and toxic pollutants, so that the crabs can spit out the sediment in the bellies, and the earthy smell is removed.

Optionally, the salinity of the aquaculture water is regulated by seawater.

By adopting the technical scheme, the salinity of the culture water is adjusted by using the seawater element, so that the salinity of the culture water is close to that of seawater, and the artificial seawater is prepared, so that pollution caused by natural seawater culture can be avoided, and the influence of external pollutants on purification and detoxification of crabs is reduced.

Preferably, the seawater element comprises the following components in parts by weight: 15-20 parts of sodium chloride, 312-320 parts of magnesium sulfate, 204-210 parts of magnesium chloride, 42-45 parts of calcium chloride, 36-40 parts of potassium chloride, 7.44-8 parts of sodium bicarbonate, 3.6-4 parts of potassium bromide and 2.4-3 parts of sodium borate.

By adopting the technical scheme, the seawater element is used for increasing the salinity of the water for cultivation, so that the influence of external pollutants on the purification of green crabs can be avoided.

In summary, the application has the following beneficial effects:

1. according to the application, green crabs are temporarily cultured in an independent culture room before being taken out of the cage, purified, removed of harmful substances and sold, and are independently cultured in the culture room, so that the situation that the green crabs are killed by oneself is avoided, the green crabs are independently fed, the content of harmful substances such as pesticide residues, heavy metals, antibiotics and the like in the green crabs is reduced, the edible safety of the green crabs is ensured, the health of consumers is ensured, and the quality of the green crabs is improved.

2. According to the application, cooked corn kernels or wheat kernels, astragalus membranaceus, garlic, astaxanthin, grassleaf sweelflag rhizome and the like are preferably adopted to prepare feed, the grassleaf sweelflag rhizome and the glabrous greenbrier rhizome can effectively purify water quality, meanwhile, the grassleaf sweelflag rhizome and the astragalus membranaceus can also sterilize and disinfect cultivation water, the garlic and the sweet potato contain abundant microorganisms, and the feed can effectively promote the development and maturation of gonads by being matched with the astragalus membranaceus and the astaxanthin, so that the weight of crab cream of green crabs is improved, and the color of the crab cream is improved.

Detailed Description

Preparation examples 1 to 6 of feeds

Preparation example 1: (1) Uniformly mixing 20kg of cooked corn kernels with 20kg of water and 0.4kg of lime powder, soaking for 10 hours at room temperature, and fishing out for later use;

(2) Decocting 6kg of radix astragali and 4kg of rhizoma Acori Graminei with 5kg of water for 1h, filtering, and collecting filtrate;

(3) Steaming 4kg of garlic, 7kg of gynura bicolor and 3kg of sweet potato, and mashing into mud for later use;

(4) Mixing the product obtained in the step (1) with the filtrate obtained in the step (2), adding the product obtained in the step (3), mixing with 8kg of astaxanthin, extruding, granulating, balling and drying.

Preparation example 2: (1) Mixing 10kg of cooked wheat grains, 10kg of water and 0.2kg of lime powder uniformly, soaking for 8 hours at room temperature, and fishing out for later use;

(2) Decocting 3kg of radix astragali and 2kg of rhizoma Acori Graminei with 3kg of water for 2h, filtering, and collecting filtrate;

(3) Steaming 1kg of garlic, 4kg of gynura bicolor and 1kg of sweet potato, and mashing into mud for later use;

(4) Mixing the product obtained in the step (1) with the filtrate obtained in the step (2), adding the product obtained in the step (3), mixing with 3kg of astaxanthin, extruding, granulating, balling and drying.

Preparation example 3: the difference from preparation example 1 is that rhizoma Acori Graminei, herba Equiseti Arvinsis and radix astragali are not added.

Preparation example 4: the difference from preparation example 1 is that garlic, sweet potato and astragalus root are not added.

Preparation example 5: the difference from preparation example 1 is that astaxanthin was not added.

Preparation example 6: the difference from preparation 1 is that the cooked corn kernels are peeled first and then mixed with hydrated lime powder.

Examples

Example 1: a method for purifying harmful substances in a hairy crab green crab body comprises the following steps:

selecting green crabs: selecting green crabs which are complete and strong in body type, free of diseases and injuries, active and good in performance and regular in specification for purifying and culturing: one crab is placed in an independent culture room, the culture room is a crab apartment, culture water which flows circularly at room temperature is utilized for culture, the depth of the culture water can enable the green crabs to be immersed in the culture water, the temperature of the culture water is reduced to 0 ℃ at a speed of 1.5 ℃/d, the salinity of the culture water is increased to 20 permillage at a speed of 1 permillage/d in the culture process, purified culture is completed, the ammonia nitrogen content of the culture water is less than 0.1mg/L, the content of sub-salt is less than 0.01mg/L, the pH value is 8.4, the dissolved oxygen content is 10ppm, once feed is fed in the morning and evening every day, the feed is boiled corn grains, the daily feeding amount is 8% of the weight of the green crabs, the culture water which is discharged circularly is circulated into the culture room again after biological purification, physical filtration and ultraviolet disinfection in sequence, the transparency of the culture water in the culture room is kept to be 50cm, the salinity of the culture water is regulated by using seawater, and the seawater is prepared by 15g sodium chloride, 312g magnesium sulfate, 204g magnesium chloride, 42g potassium chloride, 36g potassium chloride, 7.44g sodium chloride, 3.6g sodium borate and 2g sodium bromide are mixed.

Example 2: a method for purifying harmful substances in a hairy crab green crab body comprises the following steps:

selecting green crabs: selecting green crabs which are complete and strong in body type, free of diseases and injuries, active and good in performance and regular in specification for purifying and culturing: one crab is placed in an independent culture room, the culture room is a crab apartment, culture water which flows circularly at room temperature is utilized for culture, the depth of the culture water can enable the green crabs to be immersed in the culture water, the temperature of the culture water is reduced to 0 ℃ at a speed of 2 ℃/d in the culture process, the salinity of the culture water is increased to 5 permillage at a speed of 2 permillage/d, purified culture is completed, the ammonia nitrogen content of the culture water is less than 0.1mg/L, the content of the sub-salt is less than 0.01mg/L, the pH value is 7.5, the dissolved oxygen content is 8ppm, feed is fed once a day and a night, the feed is cooked wheat grains, the daily feeding amount is 3% of the weight of the green crabs, the culture water discharged circularly is recycled into the culture room after biological purification, physical filtration and ultraviolet disinfection in sequence, the transparency of the culture water in the culture room is kept to be 60cm, the salinity of the culture water is regulated by using seawater, and the seawater is prepared by 15g sodium chloride, 312g magnesium sulfate, 204g magnesium chloride, 42g calcium chloride, 36g potassium chloride, 7.44g potassium chloride, 3.6g sodium borate and sodium bicarbonate are mixed and ground to form 2.4g sodium bromide.

Example 3: a method for purifying harmful substances in the body of hairy crab green crabs is different from example 1 in that the feed is prepared in preparation example 1.

Example 4: a method for purifying harmful substances in the body of hairy crab green crabs is different from example 1 in that the feed is prepared by preparation example 2.

Example 5: a method for purifying harmful substances in the body of hairy crab green crabs is different from example 1 in that the feed is prepared in preparation example 3.

Example 6: a method for purifying harmful substances in the body of hairy crab green crabs is different from example 1 in that the feed is prepared in preparation example 4.

Example 7: a method for purifying harmful substances in the body of hairy crab green crabs is different from example 1 in that the feed is prepared in preparation example 5.

Example 8: a method for purifying harmful substances in the body of hairy crab green crabs is different from example 1 in that the feed is prepared in preparation example 6.

Comparative example

Comparative example 1: a method for purifying harmful substances in green crab body of hairy crab comprises reducing the temperature of breeding water from room temperature to 5deg.C at a rate of 5deg.C/d, and increasing salinity to 20% at a rate of 5% per mill/d.

Comparative example 2: green crabs are commercially available.

Performance test

The purification cultivation of green crabs was carried out according to the purification methods of examples 1-3 and comparative examples 1-2, and 1kg of purified green crabs were used for sensory and in vivo evaluation of toxic substances in each example, and specific results are shown in Table 1 below.

TABLE 1

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Polychlorinated biphenyls in the table are calculated as the sum of PCB27, PCB52, PCB101, PCB118, PCB138, PCB153, and PCB 180.

As can be seen from the detection results in Table 1, the green crabs purified by the method in examples 1-3 have no drug residues, pesticide residues and heavy metal residues, and meet the specified requirements in GB2762-2017, GB31650-2019, GB2760-2014, GB2733-2015, and GB 2733-2015.

In comparative example 1, the cooling rate and the salt rising rate are changed, the purifying effect on harmful substances such as pesticide residues, heavy metals, antibiotics and the like in the green crab traditional Chinese medicine is reduced, the purifying is not thorough, and some heavy metals still remain.

In contrast, comparative example 2 is a commercial green crab, and harmful substances such as heavy metals, drug residues, pesticide residues, antibiotics and the like still remain in the body, so that the green crab is unsafe to eat.

The purification of green crabs was carried out according to the methods of examples 1 to 8 and comparative example 1, the green crabs of comparative example 2 were cultivated in the cultivation water at room temperature for 10 days, the feed was fed daily in the morning and evening, the daily feeding amount was 10% of the weight of the crabs, 100 green crabs were each example or comparative example were tested, 50 green crabs each group were used, the survival rate of the green crabs and the content of floating matters in the water were recorded after the purification test was completed, the ovaries were taken out, the gonadism index was calculated, the color formation of crab cream was measured, the content of floating matters in the water= (mass of floating matters/mass of water) ×100%, the gonadism index= (gonadal weight/green crab weight) ×100%, the color formation measurement was carried out by using a rogowski fan to compare the color of ovaries, the red No. 20 was the red color was the darkest, and the red No. 34 was the statistical information was recorded in table 2.

TABLE 2

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As can be seen from the data in Table 2, the green crabs purified by the methods in examples 1 and 2 have the advantages of high survival rate, large crab cream content and good crab cream color, while the green crabs in examples 3 and 4 fed with the feeds prepared in preparation examples 1 and 3 have the advantages of increased gonadal index, redder color and better crab cream color.

The feeds prepared in preparation examples 3 and 4 were used in examples 5 and 6, respectively, and in preparation example 3, no grassleaf sweelflag rhizome, gynura segetum and astragalus root were added, in preparation example 4, no garlic, sweet potato and astragalus root were added, and in purification of green crabs in example 5, the content of floating matters in water was increased, and the gonadal index was decreased relative to that in example 3, and in example 6, the gonadal index of green crabs was decreased, and the color was decreased.

In example 7, the weight of the purified green crab cream was reduced and the degree of improvement in color formation was reduced as compared with example 3, using a feed to which astaxanthin had not been added.

In example 8, corn kernels are firstly peeled after being cooked, so that the content of floaters in the purified water body is increased, and the water quality of the culture water is affected to a certain extent.

The cooling and salt rising speeds are higher in comparative example 1, so that green crabs are difficult to adapt, the survival rate is reduced to some extent, the green crabs in comparative example 2 are purified in culture water, the floating matters in the water body are more, the crab cream is poor in color formation, and the crab cream is not full.

The present embodiment is only for explanation of the present application and is not to be construed as limiting the present application, and modifications to the present embodiment, which may not creatively contribute to the present application as required by those skilled in the art after reading the present specification, are all protected by patent laws within the scope of claims of the present application.

Claims

1. The method for purifying harmful substances in the green crab body of the hairy crab is characterized by comprising the following steps of:

purifying and culturing: placing one crab in a separate culture room, culturing by using circulating culture water at room temperature, cooling the culture water to 0 ℃ at a speed of less than or equal to 2 ℃/d, increasing the salinity to 5-20 millat a speed of less than or equal to 2 mill/d, and finishing purified culture, wherein in the culture process, the ammonia nitrogen content of the culture water is less than 0.1mg/L, the salt content is less than 0.01mg/L, the pH value is 7.5-8.4, the dissolved oxygen content is 8-10ppm, and the feed is fed once a day in the morning and evening;

the feed comprises cooked corn kernels or wheat kernels;

the feed is prepared by the following steps:

(1) Mixing cooked corn kernels or wheat kernels with water and lime powder uniformly, soaking for 8-10h, and fishing out for later use;

(4) Mixing the product obtained in the step (1) with the filtrate obtained in the step (2), adding the product obtained in the step (3), mixing with astaxanthin, extruding, granulating, balling and drying;

the feed comprises the following raw materials in parts by weight: 10-20 parts of cooked corn kernels or wheat kernels, 0.2-0.4 part of lime powder, 3-6 parts of astragalus mongholicus, 2-4 parts of grassleaf sweelflag rhizome, 1-4 parts of garlic, 4-7 parts of gynura bicolor, 1-3 parts of sweet potato and 3-8 parts of astaxanthin;

the daily feeding amount of the feed is 3-10% of the weight of the green crabs.

2. The method for purifying harmful substances in the bodies of hairy crabs according to claim 1, characterized in that the water for cultivation is recycled after biological purification, physical filtration and ultraviolet disinfection in sequence.

3. The method for purifying harmful substances in a green crab body according to claim 1, wherein the cultivation water in the cultivation room has a depth such that the green crab is immersed in the cultivation water.

4. The method for purifying harmful substances in the bodies of hairy crab according to claim 1, wherein the transparency of the cultivation water in the cultivation room is maintained at 40-60cm.

5. The method for purifying harmful substances in the body of hairy crab according to claim 1, wherein the salinity of the aquaculture water is regulated with seawater.

6. The method for purifying harmful substances in a hairy crab according to claim 5, wherein the seawater element comprises the following components in parts by weight: 15-20 parts of sodium chloride, 312-320 parts of magnesium sulfate, 204-210 parts of magnesium chloride, 42-45 parts of calcium chloride, 36-40 parts of potassium chloride, 7.44-8 parts of sodium bicarbonate, 3.6-4 parts of potassium bromide and 2.4-3 parts of sodium borate.