A method for preparing lipids of crustacean aquatic products based on coupling of aqueous agent and subcritical principle

Abstract

The application discloses a method for preparing crustacean aquatic product lipid based on water agent and subcritical principle coupling, and belongs to the technical field of aquatic product processing waste / by-product utilization. The method uses crustacean aquatic products and their waste / by-products as raw materials, constructs a technology for preparing lipid through drying, crushing and water agent and subcritical principle coupling, and obtains crustacean aquatic product lipid and its functional components, effectively improves the comprehensive utilization effect of aquatic product processing waste / by-product, and provides a new path for high-quality and high-value utilization of crustacean aquatic products and their by-products.

Description

Technical Field

[0001] This invention relates to the field of utilization technology of waste / byproducts from aquatic product processing, and in particular to a method for preparing lipids from crustacean aquatic products based on the coupling of aqueous agents and subcritical principles. Background Technology

[0002] Crustacean aquatic product by-products mainly include the head, shell, and tail, accounting for approximately 40-60% of the total mass of the crustacean aquatic product. Currently, only a small amount of crustacean aquatic product by-products are processed into animal feed, with the majority being discarded, causing environmental pollution and resource waste. Studies have shown that crustacean aquatic product by-products are rich in functional fatty acids, phospholipids, and carotenoids, possessing potential health benefits such as antioxidant, anti-inflammatory, heart health regulation, arthritis symptom relief, cognitive function improvement, and prevention of depression and anxiety, making them highly promising for development. For example, Antarctic krill oil has been developed into functional foods with uric acid-lowering and blood lipid-lowering effects. Achieving high-quality processing and high-value utilization of crustacean aquatic product by-products to improve their economic benefits is of significant practical importance. However, due to their heat sensitivity, conventional hot reflux extraction and organic solvent extraction methods for the effective substances in crustacean aquatic product by-products not only yield low amounts but also easily destroy the effective components. Developing new technologies and equipment for efficient extraction of effective components that are easy to industrialize has become a focus of attention in this field.

[0003] Currently, the main methods for preparing animal lipids include cooking and pressing, organic solvent extraction, supercritical fluid extraction, and aqueous enzymatic extraction. Cooking and pressing is widely used for large-scale preparation of animal lipids, but it suffers from low yields and high impurity levels; high-temperature cooking can also destroy active components and cause environmental pollution. Organic solvent extraction is energy-intensive, leaves solvent residues, and the extract contains sugars, proteins, amino acids, pigments, and other non-active substances, resulting in high wastewater treatment costs. Supercritical fluid extraction has high production costs and requires sophisticated equipment, limiting its large-scale application. Ultrasonic extraction is simple, energy-saving, time-saving, and low-polluting, but all methods require organic solvents; therefore, the demand for green and environmentally friendly lipid preparation technologies is increasingly strong. Aqueous enzymatic extraction offers mild conditions, simple equipment, and is environmentally friendly, but the high price of enzymes also limits its application. The aqueous extraction method utilizes the differences in the affinity of non-oil components for water and oil, as well as the differences in oil and water density, to separate oils and proteins. This method can simultaneously extract oils and proteins from oilseeds, is simple to operate, has mild operating conditions, and produces high-quality oil. While environmentally friendly and safe, the aqueous extraction method suffers from emulsification and low oil extraction rates, limiting its widespread application. Research has found that water is an environmentally friendly and safe solvent. At room temperature and pressure, water exhibits strong polarity, and based on the principle of "like dissolves like," it can be used to extract polar substances. Subcritical technology uses a subcritical fluid as an extractant in a closed, oxygen-free, low-pressure vessel. Based on the principle of "like dissolves like," it utilizes molecular diffusion during the reaction between the material and the extractant to transfer fat-soluble components from the solid material to the liquid extractant. The extractant is then separated from the target product through a reduced-pressure evaporation process. In other words, the extraction and desolvation processes are carried out at room temperature or low temperature, and the extracted material does not need to undergo a high-temperature process, allowing heat-sensitive components to be retained. Subcritical fluids are substances that exist in liquid form under conditions where the temperature is above their boiling point but below their critical temperature, and the pressure is below their critical pressure. Subcritical fluid technology offers advantages such as being non-toxic, harmless, environmentally friendly, pollution-free, non-thermal processing, minimal damage to the active ingredients in the extract, non-oxidation, low operating costs, and ease of product separation; the extraction solvent can also be recycled. Furthermore, extractants such as propane and butane are listed in China's food additive catalog, posing a low risk of food safety issues.

[0004] In response to the current problems in the preparation of marine biological lipids, such as the large amount of organic solvents used, solvent residues in the products, and the high extraction temperature which easily destroys the efficacy of heat-sensitive active ingredients, there is an urgent need for an extraction method that can improve the yield and quality of lipids from aquatic products and their by-products. Summary of the Invention

[0005] The purpose of this invention is to provide a method for preparing lipids from crustacean aquatic products based on the coupling of aqueous solutions and subcritical principles, in order to solve the problems existing in the prior art. This invention starts with the reconstruction of lipid extraction technology and takes the analysis of the composition of the extractant as the starting point to construct a lipid preparation technology based on the coupling of aqueous solutions and subcritical principles, which effectively improves the utilization efficiency of crustacean aquatic products and realizes the efficient utilization of biological resources.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] This invention provides a method for preparing lipids from crustacean aquatic products, comprising the following steps: using crustacean aquatic products and their by-products as raw materials, and combining aqueous extraction and subcritical extraction to obtain the lipids from the crustacean aquatic products.

[0008] Preferably, the aqueous solution contains an organic solvent; the organic solvent includes ethanol, acetone, and n-hexane; the volume percentage of the organic solvent in the aqueous solution is less than 50%, and the solvent is water; the extraction conditions of the aqueous solution are: a solid-liquid ratio of 1:(2-20) g / mL, an extraction temperature of 10-75 ℃, and an extraction time of 30-180 min; the subcritical extractant includes butane, propane, ethanol, and dimethyl ether; the extraction conditions of the subcritical extractant are: a solid-liquid ratio of 1:(2-20) g / mL, an extraction pressure of 0.1-1.0 MPa, an extraction temperature of 10-75 ℃, and an extraction time of 30-180 min.

[0009] Preferably, after the first step of aqueous extraction, the residue is dried before the second step of subcritical extraction.

[0010] Preferably, after the first step of extraction with a subcritical extractant, the residue does not need to be dried before proceeding directly to the second step of aqueous extraction.

[0011] Preferably, the volume percentage of organic solvent in the aqueous solution is 49%; the extraction conditions for the aqueous solution are: a solid-liquid ratio of 1:10 g / mL, an extraction temperature of 40 ℃, and an extraction time of 120 min; the extraction conditions for the subcritical extractant are: a solid-liquid ratio of 1:10 g / mL, an extraction pressure of 0.8 MPa, an extraction temperature of 40 ℃, and an extraction time of 120 min.

[0012] Preferably, the aqueous agent is an aqueous solution of ethanol; and the subcritical extractant is butane.

[0013] Preferably, the raw material needs to be pretreated before extraction; the pretreatment method is drying and pulverizing; the drying should achieve a raw material moisture content of ≤10%; the pulverized particle size is 20-60 mesh.

[0014] Preferably, the crustacean aquatic products include shrimp and crab aquatic products.

[0015] The present invention also provides a lipid for crustacean aquatic products prepared using the preparation method described above.

[0016] The present invention also provides the application of the preparation method described herein in the preparation of lipids in crustacean aquatic products.

[0017] The present invention discloses the following technical effects:

[0018] This invention uses crustacean aquatic product by-products as raw materials and improves lipid yield through a two-step method involving drying, pulverization, and a coupled aqueous-subcritical extraction principle. Compared with currently used one-step extraction technologies, this invention employs a two-step method coupled with aqueous-subcritical technology to obtain both polar and non-polar lipids, reducing the amount of organic solvent used and effectively improving resource utilization efficiency.

[0019] This invention employs different techniques for continuous extraction, yielding two different products. The process is simple, with high raw material utilization and high added value, providing a new pathway for the high-quality utilization of crustacean aquatic product by-products. All solvents used in this invention are low-boiling-point solvents, which maximize the retention of heat-sensitive components while enabling rapid desolvation at lower temperatures, leaving no solvent residue in the products. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a flowchart of the extraction process for lipids, a byproduct of crustacean aquatic products. Detailed Implementation

[0022] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, features and embodiments of the present invention.

[0023] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0024] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0025] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be readily apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0026] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0027] Flowchart for the extraction of lipids from crustacean aquatic product byproducts, see [link / reference]. Figure 1 Examples 1-8 below use the same crustacean aquatic products and their by-products as raw materials. Specifically, the raw materials are a mixture of by-products of whiteleg shrimp, red prawn, and Antarctic krill, which are briefly described as crustacean aquatic product by-products.

[0028] Example 1

[0029] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 20 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0030] Step 2). Using dried and pulverized crustacean by-products as raw materials, lipids (mainly polar substances) were extracted using aqueous extraction technology (ethanol volume percentage 0, solvent: water). The conditions for aqueous extraction were: a material-to-liquid mass-to-volume ratio of 1:2 g / mL, an extraction temperature of 10 ℃, and an extraction time of 30 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0031] Step 3). Using the above residue as raw material, dry it to a moisture content ≤10%, and extract lipids (mainly non-polar substances) using subcritical technology (butane as the extractant). The mass-to-volume ratio of the material to the liquid is 1:2 g / mL, and the preparation conditions are: extraction pressure 0.5 MPa, extraction temperature 10 ℃, and extraction time 30 min. Calculate the lipid extraction rate.

[0032] Example 2

[0033] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 20 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0034] Step 2). Using dried and pulverized crustacean aquatic product by-products as raw materials, lipids (mainly non-polar substances) were extracted using subcritical technology (butane as the extraction solvent). The mass-to-volume ratio of material to liquid was 1:10 g / mL, and the preparation conditions were: extraction pressure 0.1 MPa, extraction temperature 40 ℃, and extraction time 100 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0035] Step 3). Using the above residue as raw material (no drying required), extract lipids (mainly polar substances) using aqueous extraction technology (ethanol volume percentage 0, solvent: water). The conditions for aqueous extraction are: material-to-liquid mass-to-volume ratio 1:10 g / mL, extraction temperature 40 ℃, extraction time 100 min, and calculate the lipid extraction rate.

[0036] Example 3

[0037] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 60 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0038] Step 2). Using dried and pulverized crustacean aquatic product by-products as raw materials, lipids (mainly polar substances) were extracted using aqueous extraction technology (ethanol volume percentage 49%, water as solvent). The conditions for aqueous extraction were: material-to-liquid mass-to-volume ratio 1:20 g / mL, extraction temperature 75 ℃, and extraction time 180 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0039] Step 3). Using the above residue as raw material, dry it to a moisture content ≤10%, and extract lipids (mainly non-polar substances) using subcritical technology (butane as the extractant). The mass-to-volume ratio of the material to the liquid is 1:20 g / mL, and the preparation conditions are: extraction pressure 1.0 MPa, extraction temperature 75 ℃, and extraction time 180 min. Calculate the lipid extraction rate.

[0040] Example 4

[0041] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 60 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0042] Step 2). Using dried and pulverized crustacean aquatic product by-products as raw materials, lipids (mainly non-polar substances) were extracted using subcritical technology (butane as the extractant). The mass-to-volume ratio of material to liquid was 1:10 g / mL, and the preparation conditions were: extraction pressure 0.8 MPa, extraction temperature 40 ℃, and extraction time 120 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0043] Step 3). Using the above residue as raw material (no drying required), extract lipids (mainly polar substances) using aqueous extraction technology (ethanol volume percentage of 49%, solvent is water). The conditions for aqueous extraction are: material-to-liquid mass-to-volume ratio of 1:10 g / mL, extraction temperature of 40 ℃, and extraction time of 120 min. Calculate the lipid extraction rate.

[0044] Example 5

[0045] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 40 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0046] Step 2). Using dried and pulverized crustacean byproducts as raw materials, lipids (mainly polar substances) were extracted using aqueous extraction technology (ethanol volume percentage 30%, water as solvent). The conditions for aqueous extraction were: a material-to-liquid mass-to-volume ratio of 1:10 g / mL, an extraction temperature of 30 ℃, and an extraction time of 120 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0047] Step 3). Using the above residue as raw material, dry it to a moisture content ≤10%, and extract lipids (mainly non-polar substances) using subcritical technology (butane as the extractant). The mass-to-volume ratio of the material to the liquid is 1:10 g / mL, and the preparation conditions are: extraction pressure 0.5 MPa, extraction temperature 30 ℃, and extraction time 120 min. Calculate the lipid extraction rate.

[0048] Example 6

[0049] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 40 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0050] Step 2). Using dried and pulverized crustacean aquatic product by-products as raw materials, lipids (mainly non-polar substances) were extracted using subcritical technology (butane as the extraction solvent). The mass-to-volume ratio of material to liquid was 1:10 g / mL, and the preparation conditions were: extraction pressure 0.5 MPa, extraction temperature 30 ℃, and extraction time 120 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0051] Step 3). Using the above residue as raw material (no drying required), extract lipids (mainly polar substances) using aqueous extraction technology (ethanol volume percentage of 30%, solvent is water). The conditions for aqueous extraction are: material-to-liquid mass-to-volume ratio of 1:10 g / mL, extraction temperature of 30 ℃, and extraction time of 120 min. Calculate the lipid extraction rate.

[0052] Example 7

[0053] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 40 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0054] Step 2). Using dried and pulverized crustacean by-products as raw materials, lipids (mainly polar substances) were extracted using aqueous extraction technology (15% ethanol by volume, water as solvent). The conditions for aqueous extraction were: a material-to-liquid mass-to-volume ratio of 1:15 g / mL, an extraction temperature of 40 ℃, and an extraction time of 60 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0055] Step 3). Using the above residue as raw material, dry it to a moisture content ≤10%, and extract lipids (mainly non-polar substances) using subcritical technology (butane as the extractant). The mass-to-volume ratio of the material to the liquid is 1:15 g / mL, and the preparation conditions are: extraction pressure 0.5 MPa, extraction temperature 40 ℃, and extraction time 60 min. Calculate the lipid extraction rate.

[0056] Example 8

[0057] Step 1). A mixture of by-products from Litopenaeus vannamei, Procambarus clarkii, and Antarctic krill (referred to as crustacean aquatic product by-products) is used as raw material; the raw material is pretreated by drying and pulverizing. The pretreatment method is vacuum freeze-drying until the moisture content is ≤10%, pulverizing to 40 mesh, to obtain dried and pulverized crustacean aquatic product by-products, which are stored at 4 ℃ for later use.

[0058] Step 2). Using dried and pulverized crustacean aquatic product by-products as raw materials, lipids (mainly non-polar substances) were extracted using subcritical technology (butane as the extraction solvent). The mass-to-volume ratio of material to liquid was 1:15 g / mL, and the preparation conditions were: extraction pressure 0.5 MPa, extraction temperature 40 ℃, and extraction time 60 min. The residue was collected for later use, and the lipid extraction rate was calculated.

[0059] Step 3). Using the above residue as raw material (no drying required), extract lipids (mainly polar substances) using aqueous extraction technology (ethanol volume percentage of 15%, solvent is water). The conditions for aqueous extraction are: material-to-liquid mass-to-volume ratio of 1:15 g / mL, extraction temperature of 40 ℃, and extraction time of 60 min. Calculate the lipid extraction rate.

[0060] Results and Analysis

[0061] The formula for calculating lipid extraction rate is as follows.

[0062]

[0063] The lipid extraction rates of Examples 1-8 are shown in Table 1.

[0064] Table 1 Comparative Analysis of Lipid Extraction Rate

[0065]

[0066] As shown in Table 1, crustacean aquatic products and their byproducts were used as raw materials. The raw materials underwent drying and pulverization pretreatment. Lipids (mainly non-polar substances) were extracted using subcritical technology (butane as the extractant), and the residue was collected for later use. The lipid extraction rate was calculated. Using the aforementioned residue as raw material (without drying), lipids (mainly polar substances) were extracted using aqueous extraction technology (organic solvent:water < 1:1 (V / V), i.e., water as the solvent), and the lipid extraction rate was calculated (both methods were combined). The results showed that, through pairwise comparison, the lipid extraction rate using the subcritical-aqueous coupling technology was superior to that using the aqueous-subcritical coupling technology. This is mainly because the residue from the intermediate step of the subcritical-aqueous coupling technology does not require drying, while the residue from the intermediate step of the aqueous-subcritical coupling technology requires drying before proceeding to the next step. Drying affects the lipid content and composition in the sample.

[0067] Application Example 1

[0068] Lipids were extracted from byproducts of whiteleg shrimp, red prawn, and Antarctic krill, following the preparation method of Example 4; other conditions were the same as in Example 4.

[0069] The basic quality of lipids is shown in Table 2, and the fatty acid composition analysis of lipids is shown in Table 3. Peroxide value (GB / T 5009.37-2003), acid value (GB / T 5530-2005), and iodine value (GB / T 5532-2008) were tested according to national standard methods.

[0070] Table 2 Comparative analysis of basic lipid qualities

[0071]

[0072] As shown in Table 2, the Antarctic krill oil, Litopenaeus vannamei oil, and Procambarus clarkii oil prepared according to the method in Example 4 all met the secondary standard for peroxide value and iodine value; their color, odor, and taste also met the secondary standard, indicating that this technology has good application potential. Although this technology can achieve certain standards for Antarctic krill oil, Litopenaeus vannamei oil, and Procambarus clarkii oil extracted from different raw materials, there are still differences in the quality indicators of oils obtained from different raw materials.

[0073] Table 3. Analysis of lipid fatty acid composition

[0074]

[0075] Continued:

[0076]

[0077] Note: — indicates that the content of this component is zero.

[0078] As shown in Table 3, this technology has a certain impact on the types and contents of fatty acids in oils obtained from different raw materials. Antarctic krill oil has the most diverse fatty acid components, followed by red prawn oil, while Litopenaeus vannamei oil has the fewest. This indicates that even using the same technology, the types and composition of fatty acids vary depending on the raw materials used.

[0079] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the essential spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing lipids from crustacean aquatic products, characterized in that, The process includes the following steps: using crustacean aquatic products and their by-products as raw materials, and combining aqueous extraction and subcritical extraction to obtain the lipids of the crustacean aquatic products; after the first step of aqueous extraction, the residue is dried before the second step of subcritical extraction, or after the first step of subcritical extraction, the residue does not need to be dried before the second step of aqueous extraction. The aqueous solution is an aqueous solution of ethanol; the volume percentage of ethanol in the aqueous solution is less than 50%, and the solvent is water; the extraction conditions of the aqueous solution are: a solid-liquid ratio of 1:(2-20) g / mL, an extraction temperature of 10-75 ℃, and an extraction time of 30-180 min; the subcritical extractant is butane; the extraction conditions of the subcritical extractant are: a solid-liquid ratio of 1:(2-20) g / mL, an extraction pressure of 0.1-1.0 MPa, an extraction temperature of 10-75 ℃, and an extraction time of 30-180 min.

2. The preparation method according to claim 1, characterized in that, The aqueous solution contains 49% ethanol by volume. The extraction conditions for the aqueous solution are: a solid-liquid ratio of 1:10 g / mL, an extraction temperature of 40 ℃, and an extraction time of 120 min. The extraction conditions for the subcritical extractant are: a solid-liquid ratio of 1:10 g / mL, an extraction pressure of 0.8 MPa, an extraction temperature of 40 ℃, and an extraction time of 120 min.

3. The preparation method according to claim 1, characterized in that, Before extraction, the raw materials need to be pretreated; the pretreatment method is drying and pulverizing; the drying should reach a moisture content of ≤10%; the pulverized particles should be 20-60 mesh.

4. The preparation method according to claim 1, characterized in that, The crustacean aquatic products include shrimp and crab aquatic products.

5. A crustacean aquatic product lipid prepared by the preparation method according to any one of claims 1-4.

6. The application of the preparation method according to any one of claims 1-4 in the preparation of lipids in crustacean aquatic products.

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