Arsenic removal method for euphausia superba oil

Abstract

The invention provides a method for removing arsenic from euphausia superba oil, and belongs to the technical field of food processing. Active bamboo charcoal is laid on a flat plate at the bottom of an arsenic removal device; the euphausia superba oil is added into an arsenic removal device from the top, then adsorbed by active bamboo charcoal at the bottom, filtered and then flows out; the euphausia superba oil flowing out is subjected to adsorption operation repeatedly, and the euphausia superba oil subjected to arsenic removal is obtained. The adsorption effect of the self-made active bamboo charcoal is utilized, the adding proportion of the euphausia superba oil and the active bamboo charcoal, the adsorption temperature and pressure and the like are controlled, the total arsenic content in the euphausia superba oil can be greatly reduced and is far lower than the specified content of the national food safety standard, operation is easy, time and labor are saved, and the method is suitable for industrial production. The large-scale mass production of the arsenic-removed euphausia superba oil can be realized

Description

Technical Field

[0001] The invention belongs to the technical field of food processing, and in particular relates to a method for removing arsenic from Antarctic krill oil. Background Art

[0002] Krill is a small crustacean native to the Antarctic waters. Krill oil is a fat extracted from Antarctic krill. It is rich in nutrients, especially phospholipids, ω-3 polyunsaturated fatty acids, astaxanthin and other active ingredients, and has significant nutritional and health benefits. Krill contains heavy metals from the ocean, such as arsenic, including organic arsenic and inorganic arsenic. Arsenic is a toxic heavy metal element that may cause a variety of harms to the human body. Arsenic poisoning usually has symptoms such as damage to the nervous system, skin lesions, and damage to the digestive system. Therefore, krill crude oil must be treated to reduce and remove arsenic.

[0003] The main methods for removing arsenic from crude krill oil include adsorption, precipitation, distillation and oxidation-reduction methods. The distillation method requires dissolving the crude krill oil in an organic solvent to obtain a mixed solution, then mixing the mixed solution with an adsorbent, stirring under reflux, rotary evaporation, and filtering to obtain dearsenicized Antarctic krill oil. Chinese patent CN110878231A discloses a low-arsenic Antarctic krill oil and a method for preparing the same. The method comprises dissolving the crude Antarctic krill oil in anhydrous ethanol to obtain a first mixed solution, mixing the first mixed solution with an adsorbent (the adsorbent is made of attapulgite loaded with FeCl3) for dearsenic treatment, removing the adsorbent attapulgite to obtain a second mixed solution; and then desolventizing the second mixed solution to obtain the low-arsenic Antarctic krill oil. The existing methods are time-consuming and labor-intensive, with many processes, and are not suitable for large-scale mass production of krill oil. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a method for removing arsenic from Antarctic krill oil to solve the problems of existing arsenic removal methods such as long time consumption, complex operation, and unsuitable for mass production.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a method for removing arsenic from Antarctic krill oil, comprising the following steps:

[0007] 1) Laying activated bamboo charcoal on a flat plate at the bottom of the arsenic removal device;

[0008] 2) Adding Antarctic krill oil into the arsenic removal device from the top, and then adsorbing and filtering through the activated bamboo charcoal at the bottom before flowing out;

[0009] 3) Repeat the operation of step 2) with the outflowing Antarctic krill oil to obtain the arsenic-free Antarctic krill oil.

[0010] Preferably, in step 1), the activated bamboo charcoal is cylindrical particles with a diameter of 5.5-6.5 mm and a length of 12-15 mm, and the laying height of the activated bamboo charcoal is 1 / 2-1 / 4 of the height of the arsenic removal device.

[0011] Preferably, the plate in step 1) is a filter plate, and holes are provided on the plate, and the diameter of the holes is 3 to 5 mm.

[0012] Preferably, the method for preparing activated bamboo charcoal in step 1) comprises the following steps: pyrolyzing and carbonizing bamboo to obtain activated bamboo charcoal.

[0013] Preferably, the temperature of the pyrolysis carbonization is 700-900° C., and the time of the pyrolysis carbonization is 2.5-3 h.

[0014] Preferably, in step 2), the height of adding the Antarctic krill oil is 2 to 5 times the height of laying the activated bamboo charcoal.

[0015] Preferably, in step 2), the adsorption temperature is 40° C. to 45° C., the adsorption pressure is 0.2 Pa to 0.4 Pa, and the adsorption time is 20 to 40 min.

[0016] Preferably, in step 2), the Antarctic krill oil is allowed to stand in the arsenic removal device for 2.5 to 3 hours before adsorption.

[0017] Preferably, the number of repetitions in step 3) is 2 to 4 times.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention utilizes the adsorption effect of homemade activated bamboo charcoal and controls the addition ratio of Antarctic krill oil and activated bamboo charcoal as well as the temperature and pressure of adsorption, so as to greatly reduce the total arsenic content in Antarctic krill oil to a level far below the prescribed content of national food safety standards. The invention is simple to operate, saves time and effort, and can realize large-scale mass production of dearsenicized Antarctic krill oil. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a schematic diagram of the arsenic removal tank (wherein 1 is Antarctic krill oil, 2 is activated bamboo charcoal, 3 is a stainless steel filter plate, 4 is the tank body, 5 is the tank jacket, and 6 is Antarctic krill oil drops). DETAILED DESCRIPTION

[0021] The present invention provides a method for removing arsenic from Antarctic krill oil, comprising the following steps:

[0022] 1) Laying activated bamboo charcoal on a flat plate at the bottom of the arsenic removal device;

[0023] 2) Adding Antarctic krill oil into the arsenic removal device from the top, and then adsorbing and filtering through the activated bamboo charcoal at the bottom before flowing out;

[0024] 3) Repeat the operation of step 2) with the outflowing Antarctic krill oil to obtain the arsenic-free Antarctic krill oil.

[0025] In the present invention, homemade activated bamboo charcoal is laid on a flat plate at the bottom of the arsenic removal device. The activated bamboo charcoal is a cylindrical particle with a diameter of 5.5-6.5 mm and a length of 12-15 mm. The preparation method of the activated bamboo charcoal includes the following steps: pyrolysis and carbonization of bamboo to obtain activated bamboo charcoal; the bamboo is preferably high mountain Yinshan bamboo with a age of 4-5 years or more, and the bamboo is cut into cylinders with a diameter of 5.5-6.5 mm and a length of 12-15 mm by a bamboo machine before pyrolysis and carbonization; the pyrolysis and carbonization temperature is preferably 700-900°C, and more preferably 750-850°C; the pyrolysis and carbonization time is preferably 2.5-3h, and more preferably 2.6-2.9h; the activated bamboo charcoal has the characteristics of high mechanical strength, large pore structure, fast adsorption speed, high adsorption capacity, easy regeneration, and durability. The activated bamboo charcoal has a strong microstructure, dense and fine pores, and a specific surface area of ​​up to 2000m 2 / g, which gives it a very strong adsorption capacity, and it is easy to adsorb toxic and harmful impurities in the liquid, including heavy metals and other undesirable gases dissolved in the liquid. The high-strength activated bamboo charcoal also has the characteristics of not easily shedding carbon powder, not polluting the reaction system, and not needing to purify the reaction system again later. This has unique advantages over adsorbents such as zeolite, diatomaceous earth, and attapulgite. The laying height of the activated bamboo charcoal is preferably 1 / 2 to 1 / 4 of the height of the arsenic removal device, and more preferably 1 / 3; the arsenic removal device is preferably a arsenic removal tank, and the arsenic removal tank is such as Figure 1 As shown; the flat plate is a filter plate, and the material of the flat plate is preferably stainless steel; the flat plate is provided with holes, and the diameter of the holes is preferably 3 to 5 mm, and more preferably 4 mm.

[0026] In the present invention, Antarctic krill oil is added to the arsenic removal device from the top, and then flows out after being adsorbed and filtered by the activated bamboo charcoal at the bottom. The height of adding the Antarctic krill oil is preferably 2 to 5 times the height of the activated bamboo charcoal, and more preferably 3 to 4 times the height of the activated bamboo charcoal. The arsenic removal device is preferably a arsenic removal tank, and the arsenic removal tank is as follows: Figure 1As shown; before the adsorption, the Antarctic krill oil is allowed to stand in the arsenic removal device for 2.5 to 3 hours, and the standing time is preferably 2.6 to 2.9 hours. The purpose of the standing is to allow the krill oil to penetrate into the activated bamboo charcoal layer below, that is, to allow the krill oil to fully infiltrate the activated bamboo charcoal particles, so that the Antarctic krill oil and the activated bamboo charcoal are fully fused; the adsorption temperature is preferably 40°C to 45°C, and more preferably 41 to 44°C; the adsorption temperature is controlled by the tank jacket on the arsenic removal tank, and hot water is passed into the tank jacket; the adsorption pressure is preferably 0.2Pa to 0.4Pa, and more preferably 0.3Pa; the adsorption time is preferably 20 to 40min, and more preferably 25 to 35min.

[0027] In the present invention, the outflowing Antarctic krill oil is subjected to the repeated operation of step 2) to obtain the dearsenicized Antarctic krill oil. The number of the repeated operations is preferably 2 to 4 times.

[0028] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0029] Example 1

[0030] (1) Using 4-5 years old or more high mountain Yinshan bamboo as raw material, especially Yinshan bamboo in the cold climate zone, the bamboo is cut into 6 mm diameter and 14 mm long cylinders by a bamboo machine, and then put into a preparation furnace for pyrolysis and carbonization at 800℃ for 2.8 hours to prepare activated bamboo charcoal. The activated bamboo charcoal is evenly laid on the stainless steel filter plate at the bottom of the dearsenicization tank. The filter plate has 4mm holes. After laying one layer, lay another layer. When stacking, vibrate the outer wall of the tank appropriately to make the activated bamboo charcoal in the tank automatically settle and accumulate, which plays a role of slight compaction. The height of the activated bamboo charcoal stack accounts for one third of the height of the dearsenicization tank.

[0031] (2) Hot water is passed into the tank jacket of the arsenic removal tank to keep the temperature inside the tank at 43°C. The quick-loading seal plate is opened from the top of the hemispherical tank, and Antarctic krill oil is slowly added into the arsenic removal tank. The height of the Antarctic krill oil addition is 4 times the height of the activated bamboo charcoal laying. The tank is left to stand for 3 hours to allow the krill oil to penetrate into the activated bamboo charcoal layer below, that is, to allow the krill oil to fully infiltrate the activated bamboo charcoal particles, so that the Antarctic krill oil and the activated bamboo charcoal are fully integrated. The tank is kept at a positive pressure of 0.3Pa, and then the valve at the bottom of the tank is opened to allow the Antarctic krill oil to be slowly adsorbed and filtered from the activated bamboo charcoal layer from top to bottom under the action of pressure, and then pressed out of the arsenic removal tank and flow out from the bottom of the tank. The adsorption and arsenic removal time is 30 minutes.

[0032] (3) The Antarctic krill oil that has flowed out is re-entered into the arsenic removal tank from the top of the arsenic removal tank, and the operation of step (2) is repeated three times.

[0033] Example 2

[0034] (1) Using 4-5 years old or more high mountain Yinshan bamboo as raw material, especially Yinshan bamboo in the cold climate zone, the bamboo is cut into cylinders with a diameter of 5.5 mm and a length of 12 mm by a bamboo machine, and then put into a preparation furnace for pyrolysis and carbonization at 700°C for 2.5 hours to prepare activated bamboo charcoal. The activated bamboo charcoal is evenly laid on the stainless steel filter plate at the bottom of the dearsenicization tank. The filter plate has 3mm holes. After laying one layer, lay another layer. When stacking, vibrate the outer wall of the tank appropriately to make the activated bamboo charcoal in the tank automatically settle and accumulate, which plays a role of slight compaction. The height of the activated bamboo charcoal stack accounts for one quarter of the height of the dearsenicization tank.

[0035] (2) Hot water is passed into the tank jacket of the arsenic removal tank to keep the temperature inside the tank at 40°C. The quick-loading seal plate is opened from the top of the hemispherical tank, and Antarctic krill oil is slowly added into the arsenic removal tank. The height of the Antarctic krill oil addition is twice the height of the activated bamboo charcoal laying. The tank is left to stand for 2.5 hours to allow the krill oil to penetrate into the activated bamboo charcoal layer below, that is, to allow the krill oil to fully infiltrate the activated bamboo charcoal particles, so that the Antarctic krill oil and the activated bamboo charcoal are fully integrated. The tank is kept at a positive pressure of 0.2Pa, and then the valve at the bottom of the tank is opened to allow the Antarctic krill oil to be slowly adsorbed and filtered from the activated bamboo charcoal layer from top to bottom under the action of pressure, and then pressed out of the arsenic removal tank and flow out from the bottom of the tank. The adsorption and arsenic removal time is 20 minutes.

[0036] (3) The Antarctic krill oil that has flowed out is re-entered into the arsenic removal tank from the top of the arsenic removal tank, and the operation of step (2) is repeated twice.

[0037] Example 3

[0038] (1) Using 4-5 years old or more high mountain Yinshan bamboo as raw material, especially Yinshan bamboo in the cold climate zone, the bamboo is cut into 6.5 mm diameter and 15 mm long cylinders by bamboo machine, and then put into the preparation furnace for pyrolysis and carbonization at 900℃ for 3 hours to prepare activated bamboo charcoal. The activated bamboo charcoal is evenly laid on the stainless steel filter plate at the bottom of the dearsenicization tank, and the filter plate has 5mm holes. After laying one layer, lay another layer. When stacking, vibrate the outer wall of the tank appropriately to make the activated bamboo charcoal in the tank automatically settle and accumulate, which plays a role of slight compaction. The height of the activated bamboo charcoal stack accounts for half of the height of the dearsenicization tank.

[0039] (2) Hot water is passed into the tank jacket of the arsenic removal tank to keep the temperature in the tank at 45°C. The quick-loading seal plate is opened from the top of the hemispherical tank, and Antarctic krill oil is slowly added into the arsenic removal tank. The height of the Antarctic krill oil addition is 5 times the height of the activated bamboo charcoal laying. The tank is left to stand for 2.9 hours to allow the krill oil to penetrate into the activated bamboo charcoal layer below, that is, to allow the krill oil to fully infiltrate the activated bamboo charcoal particles, so that the Antarctic krill oil and the activated bamboo charcoal are fully integrated. The tank is kept at a positive pressure of 0.4Pa, and then the valve at the bottom of the tank is opened to allow the Antarctic krill oil to be slowly adsorbed and filtered from the activated bamboo charcoal layer from top to bottom under the action of pressure, and then pressed out of the arsenic removal tank and flow out from the bottom of the tank. The adsorption and arsenic removal time is 40 minutes.

[0040] (3) The Antarctic krill oil that has flowed out is re-entered into the arsenic removal tank from the top of the arsenic removal tank and the operation of step (2) is repeated 4 times.

[0041] Experimental Example 1

[0042] 25 kg of Antarctic krill oil extracted with n-butane was subjected to arsenic removal treatment according to the method of Example 1, and the total arsenic content of the undearsenicated Antarctic krill oil, the Antarctic krill oil dearsenicated by secondary filtration and adsorption, and the Antarctic krill oil dearsenicated by the third filtration and adsorption was determined respectively. The method for determining the total arsenic content refers to GB 5009.11-2024 National Food Safety Standard Determination of Total Arsenic and Inorganic Arsenic in Food.

[0043] Experimental results: as shown in Table 1.

[0044] Table 1 Total arsenic content of Antarctic krill oil treated with different methods

[0045]

[0046]

[0047] It can be seen from Table 1 that the total arsenic content in the dearsenicized Antarctic krill oil after three filtration and adsorption is 0.94 mg / kg. The Announcement No. 4 of 2023 of the National Health Commission on the Catalogue of "Three New Foods" and Applicable Food Safety Standards (http: / / www.nhc.gov.cn / sps / s7892 / 202305 / 4c3b189ccf84474db1e84471e6e72d07 / files / f1fb0127fc0e4bbdb563f31ac1b2bc33.pdf) stipulates that the inorganic arsenic (As) in krill oil is ≤0.1 mg / kg. It can be seen that the total arsenic content in the Antarctic krill oil obtained by the method of the present invention meets the national food safety standards.

[0048] It can be seen from the above embodiments and experimental examples that the arsenic removal method of the present invention can greatly reduce the total arsenic content in Antarctic krill oil, which is far lower than the content specified in the national food safety standards. It is simple to operate, saves time and effort, and can achieve large-scale mass production of arsenic-free Antarctic krill oil.

[0049] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for removing arsenic from Antarctic krill oil, characterized in that: The following steps are involved: 1) Laying activated bamboo charcoal on a flat plate at the bottom of the arsenic removal device; 2) Adding Antarctic krill oil into the arsenic removal device from the top, and then adsorbing and filtering through the activated bamboo charcoal at the bottom before flowing out; 3) Repeat the operation of step 2) with the outflowing Antarctic krill oil to obtain the arsenic-free Antarctic krill oil.

2. The arsenic removal method according to claim 1, characterized in that: Step 1) The activated bamboo charcoal is a cylindrical particle with a diameter of 5.5-6.5 mm and a length of 12-15 mm. The laying height of the activated bamboo charcoal is 1 / 2-1 / 4 of the height of the arsenic removal device.

3. The arsenic removal method according to claim 1, characterized in that: Step 1) The plate is a filter plate, and holes are provided on the plate, and the diameter of the holes is 3 to 5 mm.

4. The arsenic removal method according to claim 1, characterized in that: Step 1) The method for preparing activated bamboo charcoal comprises the following steps: pyrolyzing and carbonizing bamboo to obtain activated bamboo charcoal.

5. The arsenic removal method according to claim 4, characterized in that: The temperature of the pyrolysis carbonization is 700-900° C., and the time of the pyrolysis carbonization is 2.5-3 hours.

6. The arsenic removal method according to claim 1, characterized in that: In step 2), the Antarctic krill oil is added to a height that is 2 to 5 times the height of the activated bamboo charcoal.

7. The arsenic removal method according to claim 1, characterized in that: Step 2) The adsorption temperature is 40°C to 45°C, the adsorption pressure is 0.2Pa to 0.4Pa, and the adsorption time is 20 to 40min.

8. The arsenic removal method according to claim 1, characterized in that: Step 2) The Antarctic krill oil before adsorption is allowed to stand in the arsenic removal device for 2.5 to 3 hours.

9. The arsenic removal method according to claim 1, characterized in that: The number of repetitions in step 3) is 2 to 4 times.

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