Method for removing plasticizer from fish oil

Abstract

The invention relates to the technical field of plasticizer removal, in particular to a method for removing a plasticizer from fish oil, which comprises the following steps: mixing the fish oil with a modified cellulose powder adsorbent, and then carrying out adsorption treatment; performing primary centrifugation on the fish oil subjected to the adsorption treatment, and extracting supernate for 60-90 minutes by using absolute ethyl alcohol at the temperature of 55-60 DEG C after the primary centrifugation; centrifuging for the second time, taking lower-layer oil, and carrying out rotary evaporation to remove residual absolute ethyl alcohol, so as to obtain the fish oil without the plasticizer; wherein the preparation raw materials of the modified cellulose powder adsorbent comprise the following components: cellulose powder, cocoanut active charcoal, diammonium hydrogen phosphate, 4-vinylpyridine and mercaptopropionate; the volume ratio of the supernate to the absolute ethyl alcohol is 1: (4-6). Through matching of the raw materials and the treatment steps, the plasticizer in the fish oil is removed under the condition that the quality of the fish oil is reserved, the production cost can be reduced while the yield of the fish oil is increased, and the preparation method is suitable for industrial production.

Description

Technical Field

[0001] The present application relates to the technical field of plasticizer removal, and in particular to a method for removing plasticizer from fish oil. Background Art

[0002] Currently, the main methods for removing plasticizers from fish oil include molecular distillation, activated carbon adsorption, and chemical reagent methods. Molecular distillation is difficult to separate due to the high boiling points of the plasticizers dibutyl phthalate, di(2-ethylhexyl) phthalate, and diisononyl phthalate. In particular, diisononyl phthalate has a boiling point close to that of fish oil, making it difficult to separate. In addition, some polyunsaturated fatty acids may oxidize due to local overheating or residual oxygen, and some natural antioxidants (such as vitamin E) or sterols may be separated along with the plasticizer removal. Activated carbon not only adsorbs plasticizers but also absorbs beneficial components in fish oil, resulting in nutritional loss. Excessive adsorption can also alter the color, flavor, and oxidative stability of the fish oil. Separation and regeneration of activated carbon after adsorption are also relatively difficult. Organic solvent extraction in the chemical reagent method may leave trace amounts of solvent, and strong acid and alkali treatments may also destroy the fish oil structure, generate saponification products or other harmful derivatives, and damage the nutritional content of the fish oil. Therefore, there is an urgent need to provide a method for removing plasticizers from fish oil that is safer and retains the quality of fish oil. Summary of the Invention

[0003] The present application aims to overcome at least one of the defects of the prior art and provide a method for removing plasticizers from fish oil. By combining raw materials and processing steps, the plasticizer in fish oil is removed while retaining the quality of the fish oil, thereby increasing the yield of fish oil and reducing production costs, and is suitable for industrial production.

[0004] In a first aspect, the present invention provides a method for removing plasticizers from fish oil, which is achieved by the following technical solutions:

[0005] A method for removing plasticizer from fish oil comprises the following steps:

[0006] (1) mixing fish oil with modified cellulose powder adsorbent and then performing adsorption treatment;

[0007] (2) taking the fish oil after the adsorption treatment and performing the first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 55-60°C for 60-90 minutes;

[0008] (3) After the extraction is completed, a second centrifugation is performed to remove the lower layer of oil, and the residual anhydrous ethanol is removed by rotary evaporation to obtain the fish oil without plasticizer;

[0009] The raw materials for preparing the modified cellulose powder adsorbent in step (1) include the following components in parts by weight: 20-25 parts of cellulose powder, 8-12 parts of coconut shell activated carbon, 3-5 parts of diammonium hydrogen phosphate, 4-6 parts of 4-vinyl pyridine, and 4-6 parts of mercaptopropionate;

[0010] The volume ratio of the supernatant in step (2) to anhydrous ethanol is 1:(4-6).

[0011] A method for removing plasticizer from fish oil according to an embodiment of the present application has at least the following beneficial effects:

[0012] The mechanism of the modified cellulose powder adsorbent of the present application for removing plasticizers is not just a simple adsorption effect. The modified cellulose powder adsorbent contains 4-vinylpyridine and mercaptopropionate. 4-vinylpyridine combines with the benzene ring of the plasticizer through hydrogen bonds or electrostatic effects, with high selectivity, which can reduce the adsorption of fatty acids and vitamins; the thiol group in mercaptopropionate forms a coordination bond with the oxygen atom in the plasticizer, which can further improve the selectivity of the modified cellulose powder adsorbent for plasticizers, improve removal efficiency and reduce nutritional loss.

[0013] This application first performs adsorption pretreatment, and then combines extraction, centrifugation and other steps. While removing the plasticizer in the fish oil, the nutritional components in the fish oil are not easily reacted, and the natural quality of the fish oil is guaranteed. At the same time, it can improve the production efficiency of the fish oil and increase the purity of the fish oil after removing the plasticizer.

[0014] The method for removing plasticizers from fish oil of the present application has a simple process flow and a simple operation process, is suitable for industrial production, and not only improves the purity of the fish oil after the plasticizer is removed, but also reduces production costs.

[0015] According to some embodiments of the present application, the preparation of the modified cellulose powder adsorbent comprises the following steps:

[0016] S1. The cellulose powder, coconut shell activated carbon, 4-vinyl pyridine and mercaptopropionate were mixed in parts by weight, and then dried, ground, and squeezed to obtain a powder;

[0017] S2. The powder prepared in step S1 is dried at 110-150°C for 30-40min;

[0018] S3. Add diammonium hydrogen phosphate and mix well, then heat to 240-300°C and calcine for 20-30 minutes. After cooling, obtain a modified cellulose powder adsorbent.

[0019] In step S1, cellulose powder, coconut shell activated carbon, 4-vinyl pyridine, and mercaptopropionate are first mixed. This ensures thorough mixing of the raw materials, preventing separation during the subsequent calcination process, and thus enhancing the adsorption performance of the prepared modified cellulose powder adsorbent. During the compression and extrusion process, the cellulose powder, 4-vinyl pyridine, and mercaptopropionate initially undergo a certain degree of cross-linking and porosification. This facilitates the formation of a porous structure in the cellulose powder during the subsequent calcination stage, thereby enhancing the adsorption efficiency of the modified cellulose powder adsorbent.

[0020] The preparation method of the modified cellulose powder adsorbent includes a drying and calcining process. The drying step is a pre-activation step, and the calcination step is an activation step. Through the two-stage process of drying and calcining, the crystal lattice is gradually destroyed, making it easier to form an amorphous active material, thereby improving the adsorption effect of impurities.

[0021] Diammonium hydrogen phosphate can further increase the porosity of the modified cellulose powder adsorbent.

[0022] According to some embodiments of the present application, the mass ratio of the fish oil to the modified cellulose powder adsorbent in step (1) is (1-2):(1-2).

[0023] According to some embodiments of the present application, the temperature of the adsorption treatment in step (1) is 75°C-90°C.

[0024] According to some embodiments of the present application, the vacuum degree of the adsorption treatment in step (1) is 95-120 hPa.

[0025] According to some embodiments of the present application, the adsorption treatment time in step (1) is 2-2.5 hours.

[0026] According to some embodiments of the present application, the rotation speed of the first centrifugation in step (2) is 4500-4800 rpm.

[0027] According to some embodiments of the present application, the time for the first centrifugation in step (2) is 5-10 minutes.

[0028] According to some embodiments of the present application, the extraction in step (2) also includes stirring. Stirring can accelerate the mixing speed between the impurities and the anhydrous ethanol, facilitate rapid extraction, help preserve the quality of the fish oil, and reduce energy consumption during extraction.

[0029] According to some embodiments of the present application, the rotation speed of the second centrifugation in step (3) is 4500-4800 rpm.

[0030] According to some embodiments of the present application, the time for the second centrifugation in step (3) is 5-10 minutes.

[0031] According to some embodiments of the present application, the temperature of the rotary evaporation in step (3) is 55-60°C.

[0032] According to some embodiments of the present application, the rotary evaporation time in step (3) is 20-30 minutes.

[0033] In a second aspect, embodiments of the present application provide fish oil from which plasticizers have been removed, obtained by the above-mentioned method for removing plasticizers from fish oil.

[0034] The fish oil from which plasticizers have been removed according to the embodiments of the present application has at least the following beneficial effects:

[0035] The plasticizer-removed fish oil obtained in the present application does not contain plasticizers and is not likely to cause harm to human health when used. It has a high purity and can promote the excretion of fat and cholesterol in human blood, control hyperlipidemia, hypertension and hypercholesterolemia, and at the same time enhance immunity and prevent the occurrence of infectious and contagious diseases. DETAILED DESCRIPTION

[0036] To make the purpose, technical solutions and advantages of this application more clear, the following will be further described in detail with reference to specific embodiments. The embodiments described here are only part of the embodiments of this application and should not be understood as limiting the scope of protection of this application.

[0037] Example 1

[0038] A method for removing plasticizer from fish oil comprises the following steps:

[0039] (1) 100 g of fish oil was mixed with 100 g of modified cellulose powder adsorbent and then subjected to adsorption treatment at a temperature of 80° C., a vacuum degree of 110 hPa, and a time of 2.2 h;

[0040] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 58° C. for 70 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:5, the speed of the first centrifugation is 4600 rpm, the time of the first centrifugation is 8 minutes, and the extraction also includes stirring;

[0041] (3) After the extraction is completed, a second centrifugation is performed to remove the lower layer of oil, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4700 rpm, the time of the second centrifugation is 7 minutes, the temperature of the rotary evaporation is 58° C., and the time of the rotary evaporation is 25 minutes;

[0042] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0043] S1. According to parts by weight, 23 parts of cellulose powder, 10 parts of coconut shell activated carbon, 5 parts of 4-vinylpyridine and 5 parts of mercaptopropionate were mixed, and then dried, ground, squeezed and extruded to obtain a powder;

[0044] S2. The powder prepared in step S1 was dried at 130°C for 35 min;

[0045] S3 was added 4 parts of diammonium phosphate and mixed, then heated to 270 ℃ calcined for 25min, and cooled to obtain a modified cellulose powder adsorbent;

[0046] The obtained fish oil after plasticizer removal was tested, and the mass of the obtained fish oil after plasticizer removal was 93.15 g. The yield of the fish oil after plasticizer removal was 93.15%, and no plasticizer was detected.

[0047] Example 2

[0048] A method for removing plasticizer from fish oil comprises the following steps:

[0049] (1) 100 g of fish oil was mixed with 200 g of modified cellulose powder adsorbent and subjected to adsorption treatment at a temperature of 75° C., a vacuum degree of 120 hPa, and a time of 2 h;

[0050] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 60° C. for 60 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:6, the speed of the first centrifugation is 4500 rpm, the time of the first centrifugation is 10 minutes, and the extraction also includes stirring;

[0051] (3) After the extraction is completed, a second centrifugation is performed to remove the oil layer, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4500 rpm, the time of the second centrifugation is 10 min, the temperature of the rotary evaporation is 55° C., and the time of the rotary evaporation is 30 min.

[0052] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0053] S1. According to parts by weight, 20 parts of cellulose powder, 12 parts of coconut shell activated carbon, 4 parts of 4-vinyl pyridine and 6 parts of mercaptopropionate were mixed, and then dried, ground, squeezed and extruded to obtain a powder;

[0054] S2. The powder prepared in step S1 was dried at 110°C for 40 min;

[0055] S3 was added 3 parts of diammonium phosphate and mixed, then heated to 300 ℃ calcined for 20min, and cooled to obtain a modified cellulose powder adsorbent;

[0056] The obtained fish oil after plasticizer removal was tested, and the mass of the obtained fish oil after plasticizer removal was 92.96 g. The yield of the fish oil after plasticizer removal was 92.96%, and no plasticizer was detected.

[0057] Example 3

[0058] A method for removing plasticizer from fish oil comprises the following steps:

[0059] (1) 100 g of fish oil was mixed with 50 g of modified cellulose powder adsorbent and subjected to adsorption treatment at a temperature of 90° C., a vacuum degree of 95 hPa, and a time of 2.5 h;

[0060] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 55° C. for 90 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:4, the speed of the first centrifugation is 4800 rpm, the time of the first centrifugation is 5 minutes, and the extraction also includes stirring;

[0061] (3) After the extraction is completed, a second centrifugation is performed to remove the oil layer, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4800 rpm, the time of the second centrifugation is 5 minutes, the temperature of the rotary evaporation is 60°C, and the time of the rotary evaporation is 20 minutes;

[0062] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0063] S1. According to parts by weight, 25 parts of cellulose powder, 8 parts of coconut shell activated carbon, 6 parts of 4-vinyl pyridine and 4 parts of mercaptopropionate were mixed, and then dried, ground, squeezed and extruded to obtain a powder;

[0064] S2. The powder prepared in step S1 was dried at 150°C for 30 min;

[0065] S3 was added 5 parts of diammonium phosphate and mixed, then heated to 240 ℃ calcined for 30min, and cooled to obtain a modified cellulose powder adsorbent;

[0066] The obtained fish oil after plasticizer removal was tested, and the mass of the obtained fish oil after plasticizer removal was 93.21 g. The yield of the fish oil after plasticizer removal was 93.21%, and no plasticizer was detected.

[0067] Example 4

[0068] A method for removing plasticizer from fish oil comprises the following steps:

[0069] (1) 100 g of fish oil was mixed with 100 g of modified cellulose powder adsorbent and then subjected to adsorption treatment at a temperature of 85° C., a vacuum degree of 105 hPa, and a time of 2.4 h;

[0070] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 56° C. for 80 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:5, the speed of the first centrifugation is 4700 rpm, the time of the first centrifugation is 6 minutes, and the extraction also includes stirring;

[0071] (3) After the extraction is completed, a second centrifugation is performed to remove the oil layer, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4700 rpm, the time of the second centrifugation is 9 minutes, the temperature of the rotary evaporation is 56° C., and the time of the rotary evaporation is 24 minutes;

[0072] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0073] S1. According to parts by weight, 22 parts of cellulose powder, 11 parts of coconut shell activated carbon, 5 parts of 4-vinyl pyridine and 5 parts of mercaptopropionate were mixed, and then dried, ground, squeezed and extruded to obtain a powder;

[0074] S2. The powder prepared in step S1 was dried at 120°C for 36 min;

[0075] S3 was added 4 parts of diammonium hydrogen phosphate and mixed, then heated to 290 ℃ calcined for 28min, and cooled to obtain a modified cellulose powder adsorbent;

[0076] The obtained fish oil after plasticizer removal was tested, and the mass of the obtained fish oil after plasticizer removal was 93.07 g. The yield of the fish oil after plasticizer removal was 93.07%, and no plasticizer was detected.

[0077] Comparative Example 1

[0078] A method for removing plasticizer from fish oil comprises the following steps:

[0079] (1) 100 g of fish oil was mixed with 100 g of modified cellulose powder adsorbent and then subjected to adsorption treatment at a temperature of 80° C., a vacuum degree of 110 hPa, and a time of 2.2 h;

[0080] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 58° C. for 70 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:5, the speed of the first centrifugation is 4600 rpm, the time of the first centrifugation is 8 minutes, and the extraction also includes stirring;

[0081] (3) After the extraction is completed, a second centrifugation is performed to remove the lower layer of oil, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4700 rpm, the time of the second centrifugation is 7 minutes, the temperature of the rotary evaporation is 58° C., and the time of the rotary evaporation is 25 minutes;

[0082] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0083] S1. According to parts by weight, 23 parts of cellulose powder, 10 parts of coconut shell activated carbon, 5 parts of 4-vinylpyridine and 5 parts of mercaptopropionate were mixed, and then dried, ground, squeezed and extruded to obtain a powder;

[0084] S2. The powder prepared in step S1 was dried at 130°C for 35 min;

[0085] S3. The temperature was then raised to 270°C and calcined for 25 min, and the modified cellulose powder adsorbent was obtained after cooling;

[0086] The obtained fish oil from which the plasticizer was removed was tested, and the mass of the obtained fish oil from which the plasticizer was removed was 93.64 g, the yield of the fish oil from which the plasticizer was removed was 93.64%, and the concentrations of the plasticizer di(2-ethylhexyl) phthalate, diisononyl phthalate, and di-n-butyl phthalate, respectively, were detected to be 7.8 mg / kg, 9.6 mg / kg, and 4.5 mg / kg.

[0087] Comparative Example 2

[0088] A method for removing plasticizer from fish oil comprises the following steps:

[0089] (1) 100 g of fish oil was mixed with 100 g of modified cellulose powder adsorbent and then subjected to adsorption treatment at a temperature of 80° C., a vacuum degree of 110 hPa, and a time of 2.2 h;

[0090] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 58° C. for 70 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:5, the speed of the first centrifugation is 4600 rpm, the time of the first centrifugation is 8 minutes, and the extraction also includes stirring;

[0091] (3) After the extraction is completed, a second centrifugation is performed to remove the lower layer of oil, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4700 rpm, the time of the second centrifugation is 7 minutes, the temperature of the rotary evaporation is 58° C., and the time of the rotary evaporation is 25 minutes;

[0092] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0093] S1. 23 parts by weight of cellulose powder, 10 parts of coconut shell activated carbon, 5 parts of 4-vinyl pyridine and 5 parts of mercaptopropionate were mixed and then dried to obtain a powder;

[0094] S2. The powder prepared in step S1 was dried at 130°C for 35 min;

[0095] S3 was added 4 parts of diammonium phosphate and mixed, then heated to 270 ℃ calcined for 25min, and cooled to obtain a modified cellulose powder adsorbent;

[0096] The obtained fish oil from which the plasticizer was removed was tested, and the mass of the obtained fish oil from which the plasticizer was removed was 93.44 g, the yield of the fish oil from which the plasticizer was removed was 93.44%, and the concentrations of the plasticizer di(2-ethylhexyl) phthalate, diisononyl phthalate, and di-n-butyl phthalate, respectively, were detected to be 4.4 mg / kg, 6.5 mg / kg, and 4.8 mg / kg.

[0097] Comparative Example 3

[0098] A method for removing plasticizer from fish oil comprises the following steps:

[0099] (1) 100 g of fish oil was mixed with 100 g of modified cellulose powder adsorbent and then subjected to adsorption treatment at a temperature of 80° C., a vacuum degree of 110 hPa, and a time of 2.2 h;

[0100] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 58° C. for 70 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:5, the speed of the first centrifugation is 4600 rpm, the time of the first centrifugation is 8 minutes, and the extraction also includes stirring;

[0101] (3) After the extraction is completed, a second centrifugation is performed to remove the lower layer of oil, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4700 rpm, the time of the second centrifugation is 7 minutes, the temperature of the rotary evaporation is 58° C., and the time of the rotary evaporation is 25 minutes;

[0102] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0103] S1. According to parts by weight, 23 parts of cellulose powder, 10 parts of coconut shell activated carbon and 5 parts of mercaptopropionate were mixed, and then dried, ground, squeezed and extruded to obtain a powder;

[0104] S2. The powder prepared in step S1 was dried at 130°C for 35 min;

[0105] S3 was added 4 parts of diammonium phosphate and mixed, then heated to 270 ℃ calcined for 25min, and cooled to obtain a modified cellulose powder adsorbent;

[0106] The obtained fish oil after plasticizer removal was tested, and the mass of the obtained fish oil after plasticizer removal was 77.43 g. The yield of the fish oil after plasticizer removal was 77.43%, and no plasticizer was detected.

[0107] Comparative Example 4

[0108] A method for removing plasticizer from fish oil comprises the following steps:

[0109] (1) 100 g of fish oil was mixed with 100 g of modified cellulose powder adsorbent and then subjected to adsorption treatment at a temperature of 80° C., a vacuum degree of 110 hPa, and a time of 2.2 h;

[0110] (2) taking the fish oil after the adsorption treatment and performing a first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 58° C. for 70 minutes, wherein the volume ratio of the supernatant to the anhydrous ethanol is 1:5, the speed of the first centrifugation is 4600 rpm, the time of the first centrifugation is 8 minutes, and the extraction also includes stirring;

[0111] (3) After the extraction is completed, a second centrifugation is performed to remove the lower layer of oil, and the residual anhydrous ethanol is removed by rotary evaporation to obtain fish oil from which the plasticizer has been removed. The speed of the second centrifugation is 4700 rpm, the time of the second centrifugation is 7 minutes, the temperature of the rotary evaporation is 58° C., and the time of the rotary evaporation is 25 minutes;

[0112] Wherein, the preparation method of the modified cellulose powder adsorbent is:

[0113] S1. According to parts by weight, 23 parts of cellulose powder, 10 parts of coconut shell activated carbon and 5 parts of 4-vinylpyridine were mixed, and then dried, ground, squeezed and extruded to obtain a powder;

[0114] S2. The powder prepared in step S1 was dried at 130°C for 35 min;

[0115] S3 was added 4 parts of diammonium phosphate and mixed, then heated to 270 ℃ calcined for 25min, and cooled to obtain a modified cellulose powder adsorbent;

[0116] The obtained fish oil after plasticizer removal was tested, and the mass of the obtained fish oil after plasticizer removal was 79.37 g. The yield of the fish oil after plasticizer removal was 79.37%, and no plasticizer was detected.

[0117] It can be seen from Examples 1-4 and Comparative Examples 1-4 of the present application that the method for removing plasticizers from fish oil of the present application can not only remove plasticizers from fish oil but also improve the yield of fish oil by matching raw materials and processing steps.

[0118] The raw materials for preparing the modified cellulose powder of Comparative Example 1 do not contain diammonium hydrogen phosphate, and the rest are the same as in Example 1. It can be seen that the concentration of the plasticizer di(2-ethylhexyl) phthalate in the fish oil from which the plasticizer has been removed is 7.8 mg / kg, the concentration of diisononyl phthalate is 9.6 mg / kg, and the concentration of di-n-butyl phthalate is 4.5 mg / kg, all of which exceed the standard. This indicates that not adding diammonium hydrogen phosphate in the preparation of the modified cellulose powder will affect the adsorption effect of the plasticizer, resulting in the inability to completely remove the plasticizer.

[0119] The modified cellulose powder of Comparative Example 2 was prepared without grinding and squeezing, and the rest was the same as in Example 1. It can be seen that the concentration of the plasticizer di(2-ethylhexyl) phthalate in the fish oil from which the plasticizer was removed was 4.4 mg / kg, the concentration of diisononyl phthalate was 6.5 mg / kg, and the concentration of di-n-butyl phthalate was 4.8 mg / kg, all of which exceeded the standard. This indicates that the cellulose powder and 4-vinylpyridine, mercaptopropionate, etc. will first undergo a certain degree of cross-linking and porosity during the squeezing process, which is more conducive to the formation of a porous structure in the cellulose powder in the subsequent calcination stage, thereby enhancing the adsorption effect of the modified cellulose powder adsorbent. The preparation of the modified cellulose powder without grinding and squeezing will affect the adsorption effect of the plasticizer, resulting in the inability to completely remove the plasticizer.

[0120] The raw materials for preparing the modified cellulose powder in Comparative Example 3 do not contain 4-vinylpyridine, and the rest are the same as in Example 1. It can be seen that the yield of the plasticizer in the fish oil after the plasticizer is removed is significantly reduced, indicating that without adding 4-vinylpyridine in the preparation of the modified cellulose powder, some of the nutrients in the fish oil will be adsorbed, resulting in a decrease in the yield of the fish oil.

[0121] The raw materials for preparing the modified cellulose powder of Comparative Example 4 do not contain mercaptopropionate, and the rest are the same as in Example 1. It can be seen that the yield of plasticizer in the fish oil after plasticizer removal is significantly reduced, indicating that without adding mercaptopropionate in the preparation of the modified cellulose powder, some of the nutrients in the fish oil will be adsorbed, resulting in a decrease in the yield of fish oil.

[0122] Although the embodiments of the present application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions or variations may be made to these embodiments without departing from the principles and purpose of the present application, and that the technical solutions after these changes, modifications, substitutions or variations will fall within the scope of protection of the present application.

Claims

1. A method for removing plasticizer from fish oil, characterized in that: The following steps are involved: (1) mixing fish oil with modified cellulose powder adsorbent and then performing adsorption treatment; (2) taking the fish oil after the adsorption treatment and performing the first centrifugation, taking the supernatant after the first centrifugation and extracting it with anhydrous ethanol at a temperature of 55-60°C for 60-90 minutes; (3) After the extraction is completed, a second centrifugation is performed to remove the lower layer of oil, and the residual anhydrous ethanol is removed by rotary evaporation to obtain the fish oil without plasticizer; The raw materials for preparing the modified cellulose powder adsorbent in step (1) include the following components in parts by weight: 20-25 parts of cellulose powder, 8-12 parts of coconut shell activated carbon, 3-5 parts of diammonium hydrogen phosphate, 4-6 parts of 4-vinyl pyridine, and 4-6 parts of mercaptopropionate; The volume ratio of the supernatant in step (2) to anhydrous ethanol is 1:(4-6).

2. The method for removing plasticizer from fish oil according to claim 1, characterized in that: The preparation of the modified cellulose powder adsorbent comprises the following steps: S1. The cellulose powder, coconut shell activated carbon, 4-vinyl pyridine and mercaptopropionate were mixed in parts by weight, and then dried, ground, and squeezed to obtain a powder; S2. The powder prepared in step S1 is dried at 110-150°C for 30-40min; S3. Add diammonium hydrogen phosphate and mix well, then heat to 240-300°C and calcine for 20-30 minutes. After cooling, obtain a modified cellulose powder adsorbent.

3. The method for removing plasticizer from fish oil according to claim 1, characterized in that: The mass ratio of the fish oil to the modified cellulose powder adsorbent in step (1) is (1-2):(1-2).

4. The method for removing plasticizer from fish oil according to claim 1, wherein: The temperature of the adsorption treatment in step (1) is 75°C-90°C; the vacuum degree of the adsorption treatment in step (1) is 95-120hPa; and the time of the adsorption treatment in step (1) is 2-2.5h.

5. The method for removing plasticizer from fish oil according to claim 1, characterized in that: The rotation speed of the first centrifugation in step (2) is 4500-4800 rpm; the time of the first centrifugation in step (2) is 5-10 min.

6. The method for removing plasticizer from fish oil according to claim 1, characterized in that: The extraction in step (2) also includes stirring.

7. The method for removing plasticizer from fish oil according to claim 1, characterized in that: The rotation speed of the second centrifugation in step (3) is 4500-4800 rpm; the time of the second centrifugation in step (3) is 5-10 min.

8. The method for removing plasticizer from fish oil according to claim 1, characterized in that: The temperature of the rotary evaporation in step (3) is 55-60°C.

9. The method for removing plasticizer from fish oil according to claim 1, characterized in that: The time of the rotary evaporation in step (3) is 20-30 minutes.

10. Fish oil with removed plasticizer obtained by the method for removing plasticizer from fish oil according to any one of claims 1 to 9.