Deodorization method, preparation method and application of euphausia superba oil

Abstract

The invention discloses a deodorization method, a preparation method and application of euphausia superba oil, and belongs to the technical field of preparation of euphausia superba oil. The deodorization method comprises the following steps: introducing crude euphausia superba oil into a deodorization device, introducing nitrogen from the bottom of the device, stirring for deodorization, and extracting nitrogen from the top of the device; during stirring for deodorization, the vacuum degree in the device is kept to be-0.06 to-0.08 Pa, and the temperature is kept to be 35 to 65 DEG C. According to the method, nitrogen is used as an adsorbent for deodorization and deodorization to remove the fishy smell in the euphausia superba oil, so that the production and operation cost can be greatly reduced, and the production process is safe and reliable and low in electrification and mechanization degree. A low-temperature and low-pressure physical method is adopted for deodorization, the character of the euphausia superba oil is not changed, the deodorized euphausia superba oil has the fresh and fragrant taste and smell of shrimps and is free of fishy smell, and technical support is provided for large-scale production and application of the euphausia superba oil.

Description

Technical Field

[0001] The invention belongs to the technical field of krill oil preparation, and in particular relates to a method for removing the smell of Antarctic krill oil, a preparation method and application thereof. Background Art

[0002] The fishy smell of Antarctic krill mainly comes from the special smell of trimethylamine, trimethylamine oxide, dimethyl sulfide and other components produced by the metabolism and corruption of organic matter in the shrimp. At present, the extraction technology of Antarctic krill oil is mainly divided into three methods: organic solvent method (such as organic solvent countercurrent extraction method mainly based on n-hexane), supercritical fluid extraction method and enzymatic method. However, the Antarctic krill oil processed by these three methods still contains the above-mentioned trimethylamine, trimethylamine oxide, dimethyl sulfide and other small molecular impurities, which makes the Antarctic krill oil have a certain shrimp oil fishy smell, which is not easy to remove.

[0003] In view of these problems, the industry generally adopts solid adsorption and filtration technology to remove fishy smell and deodorize, such as nanofiltration, deodorization or ion exchange adsorption and elution of krill oil, and removes the fishy smell in Antarctic krill oil step by step, so as to solve the problem that the fishy smell of Antarctic krill oil after extraction is difficult to remove. For example, CN108913352B provides a method for preparing deamined low-smelling krill oil, using cation exchange resin and macroporous adsorption resin as adsorption medium to adsorb krill oil or krill oil extract (crude oil), and removes amine and deodorizes. However, this method is time-consuming and laborious, and also requires a complete set of adsorption, desolventizing and eluting equipment, which increases the preparation cost of krill oil, and deodorization and deodorization are not ideal. Therefore, it is particularly important to provide a deodorization method that can effectively remove the fishy smell in Antarctic krill oil, simplify the deodorization method, and reduce the preparation cost. Summary of the invention

[0004] In view of this, the object of the present invention is to provide a method for removing the smell of Antarctic krill oil. The method of the present invention has good deodorization effect, does not change the properties of the krill oil, does not change the content of the effective ingredients of the krill oil, the effective ingredients can be effectively preserved, the deodorization method is simple, and the production and operation cost is low.

[0005] Another object of the present invention is to provide an application of the deodorization method in the preparation of Antarctic krill oil.

[0006] Another object of the present invention is to provide a method for preparing Antarctic krill oil.

[0007] Another object of the present invention is to provide Antarctic krill oil prepared by the preparation method.

[0008] Another object of the present invention is to provide a use of the Antarctic krill oil in preparing food or medicine.

[0009] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0010] The present invention provides a method for removing the smell of Antarctic krill oil, which comprises the following steps:

[0011] The crude Antarctic krill oil is introduced into a deodorizing device, nitrogen is introduced from the bottom of the device, the deodorizing is stirred, and nitrogen is extracted from the top of the device; during the deodorizing, the vacuum degree in the device is maintained at -0.06 to -0.08 Pa and the temperature is maintained at 35 to 65°C.

[0012] Preferably, the crude Antarctic krill oil is introduced into a deodorizing device to stabilize the crude oil at a temperature of 35 to 65° C. for 20 to 40 minutes.

[0013] Preferably, the nitrogen introduction rate is 0.5 to 5 L / min.

[0014] The present invention also provides an application of the deodorization method in preparing Antarctic krill oil.

[0015] The present invention also provides a method for preparing Antarctic krill oil, the preparation method comprising the following steps:

[0016] The Antarctic krill powder is granulated to form krill powder particles; the krill powder particles are extracted with an organic solvent to obtain crude Antarctic krill oil; and the crude Antarctic krill oil is deodorized by the deodorization method to obtain Antarctic krill oil.

[0017] Preferably, the granulation is extrusion rotary granulation, and the number of granulation is 3 to 5 times.

[0018] Preferably, the organic solvent comprises n-butane or propane.

[0019] Preferably, the extraction conditions include: extraction pressure of 0.4-1.0 MPa, extraction temperature of 30-45° C., and stirring speed of 30-40 rpm.

[0020] The present invention also provides Antarctic krill oil prepared by the preparation method.

[0021] The present invention also provides an application of the Antarctic krill oil in preparing food or medicine.

[0022] Beneficial effects of the present invention:

[0023] The present invention uses nitrogen as an adsorbent for deodorization and fishy smell removal to remove the fishy smell in Antarctic krill oil, which can greatly reduce the production and operation costs, and the production process is safe and reliable, and the degree of electrification and mechanization is low. The present invention uses a low-temperature and low-pressure physical method to remove fishy smell, which will not change the properties of krill oil. The krill oil after fishy smell removal has a fresh shrimp fragrance, a good fishy smell removal effect, and no fishy smell. The DHA content in the Antarctic krill oil after fishy smell removal reaches 6.1g / 100g, and the EPA content reaches 10g / 100g. The fishy smell removal process will not affect the DHA and EPA contents, providing technical support for the large-scale production and application of Antarctic krill oil.

[0024] The present invention adopts a preparation method of granulation followed by extraction. Through granulation, the particle size, particle hardness and surface smoothness of the krill dry powder are increased, and the fluidity of the particles is improved, thereby being more conducive to fluid extraction. In the granulation process of the present invention, no auxiliary materials are added, and only the viscosity of lipids in the krill dry powder is relied on. Small particles are agglomerated and transformed into large particles through extrusion and friction. At the same time, during the friction movement of the particles, the temperature of the particles gradually increases. After multiple granulations, the temperature of the krill dry powder particles can also be raised to a temperature close to that required by the subsequent extraction process, thereby improving the extraction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the deodorization device used in the deodorization process in Example 7, wherein: 1-deodorization tank, 2-air inlet valve, 3-continuous temperature control jacket, 4-screw vacuum pump unit, 5-cooling tower, 6-cooling water tank, 7-liquid inlet, 8-nitrogen exhaust port, 9-nitrogen inlet, 10-liquid outlet, 11-servo motor, 12-agitation shaft, 13-agitation blade, 14-feed valve, 15-discharge valve. DETAILED DESCRIPTION

[0026] The present invention provides a method for removing the smell of Antarctic krill oil, which comprises the following steps:

[0027] The crude Antarctic krill oil is introduced into a deodorizing device, nitrogen is introduced from the bottom of the device, the deodorizing is stirred, and nitrogen is extracted from the top of the device; during the deodorizing, the vacuum degree in the device is maintained at -0.06 to -0.08 Pa and the temperature is maintained at 35 to 65°C.

[0028] In the present invention, there is no special limitation on the source of the crude Antarctic krill oil, and the crude Antarctic krill oil can be prepared by conventional methods or purchased according to actual needs.

[0029] In the present invention, the deodorizing device can be conventionally selected according to actual needs. Preferably, a stirring device is provided inside the deodorizing device. As an optional embodiment, the deodorizing device preferably includes a deodorizing tank, an air inlet valve, a continuous temperature control jacket, a screw vacuum pump unit, a cooling tower, a cooling water tank, a liquid feed inlet, a nitrogen exhaust port, a nitrogen air inlet, a liquid feed outlet, a servo motor, a stirring shaft, a stirring blade, a feed valve, and a discharge valve.

[0030] In the present invention, the crude Antarctic krill oil is introduced into a deodorizing device, and the crude oil is preferably heated and allowed to stand for stabilization; the heating temperature is preferably 35 to 65° C., more preferably 45 to 55° C., 47 to 56° C., or 50 to 60° C.; the stabilization time is preferably 20 to 40 minutes, more preferably 25 to 35 minutes, 28 to 32 minutes, or 30 to 31 minutes.

[0031] In the present invention, after the crude Antarctic krill oil is stabilized, nitrogen is introduced from the bottom of the device to contact the crude oil in the device; the nitrogen introduction rate is preferably 0.5-5 L / min, more preferably 0.6-3 L / min or 0.89-1.2 L / min or 0.8-1 L / min.

[0032] In the present invention, after nitrogen is introduced, the device is stirred to remove the fishy smell; the stirring speed is preferably 20 to 40 rpm, more preferably 25 to 31 rpm, 29 to 35 rpm, or 30 to 33 rpm. When stirring to remove the fishy smell, the vacuum degree in the device is preferably -0.06 Pa, -0.065 Pa, -0.07 Pa, -0.075 Pa, or -0.08 Pa; the temperature in the device is preferably 45 to 55 ° C, 47 to 56 ° C, or 50 to 60 ° C.

[0033] In the present invention, nitrogen is extracted from the top of the device to remove the nitrogen that absorbs the fishy smell of krill oil.

[0034] In the present invention, the deodorization time can be conventionally selected according to actual needs; for example, deodorization of 800 kg of Antarctic krill oil requires 40 to 50 minutes of deodorization treatment.

[0035] The present invention uses nitrogen as a deodorant for gas stripping to remove the fishy smell in Antarctic krill oil, which can greatly reduce the production and operation costs, and the production process is safe and reliable, with low electrification and mechanization levels. The present invention uses a low-temperature and low-pressure physical method to remove the fishy smell, which will not change the properties of the krill oil. The krill oil after deodorization has a fresh shrimp fragrance and no fishy smell.

[0036] The present invention also provides an application of the deodorization method in preparing Antarctic krill oil.

[0037] The present invention also provides a method for preparing Antarctic krill oil, the preparation method comprising the following steps:

[0038] The Antarctic krill powder is granulated to form krill powder particles; the krill powder particles are extracted with an organic solvent to obtain crude Antarctic krill oil; and the crude Antarctic krill oil is deodorized by the deodorization method to obtain Antarctic krill oil.

[0039] In the present invention, there is no special limitation on the source of the Antarctic krill powder, which can be prepared by conventional methods or purchased; for example, Antarctic krill powder can be obtained by using Euphausia superbaDana as raw material and processing it into powder through processes such as washing, chopping, enzymatic hydrolysis and shelling, and drying.

[0040] In the present invention, the granulation is preferably extrusion rotary granulation, and the granulation machine can be conventionally selected according to actual needs, for example, a rotary extrusion granulator is used. No auxiliary materials such as adhesives are added during the granulation process of the present invention. Due to the high content of oil components inside the krill meal, there is a certain viscosity between the particles. As the friction between the particles, heat is generated, and the krill meal is bonded into a mass by the heat generated by itself. In the present invention, during the granulation process, the temperature of the particles continues to rise due to the heat generated by friction. The number of granulation times is preferably 3 to 5 times, and more preferably 4 times; when the last granulation is completed, the temperature of the krill meal particles preferably reaches 40 to 50°C, forming harder krill meal particles. The particle size of the krill meal particles is not particularly limited, and is preferably 4 to 8 mm, and more preferably 6 mm.

[0041] In the present invention, the organic solvent can be conventionally selected according to actual needs, preferably including n-butane or propane, and more preferably n-butane.

[0042] In the present invention, the extraction is preferably carried out by non-critical fluid extraction; the material-liquid mass ratio during the extraction is preferably 1:(4-6), more preferably 1:4 or 1:5 or 1:6; the extraction pressure is preferably 0.4-1.0 MPa, more preferably 0.5-0.7 MPa or 0.6-0.8 MPa or 0.7-0.9 MPa; the extraction temperature is preferably 30-45°C, more preferably 35-40°C or 33-38°C or 36-39°C; the stirring speed during the extraction is preferably 30-40 rpm, more preferably 33-36 rpm or 35-38 rpm; the standing time during the extraction is preferably 30-60 min, more preferably 35-50 min or 40-55 min or 45-50 min.

[0043] In the present invention, after the extraction is completed, the organic solvent in the extract is removed to obtain Antarctic krill oil crude oil. The organic solvent removal method is preferably to remove the organic solvent under vacuum conditions; the vacuum degree during the removal is preferably -0.5 to -0.01Pa, more preferably -0.4 to -0.05Pa or -0.3 to -0.1Pa; the temperature is preferably 50 to 60°C, more preferably 52 to 56°C or 53 to 58°C or 55°C to 57°C; the removal time is preferably 40 to 60min, more preferably 45 to 58min or 42 to 55min or 47 to 50min; the number of removals is preferably 1 to 3 times, more preferably 2 times. After the organic solvent is removed, the residual amount of organic solvent in the Antarctic krill oil crude oil is preferably ≤10mg / kg, more preferably ≤5mg / kg, and more preferably ≤1mg / kg.

[0044] In the present invention, the extraction of Antarctic krill oil crude oil is obtained by extracting Antarctic krill dry powder as raw material. Since Antarctic krill dry powder is fine and light in weight, it has poor fluidity after mixing with organic solvents and is in a floating state in liquid organic solvents, which is not conducive to the implementation of the extraction process. Therefore, the present invention increases the particle size, particle hardness and surface smoothness of the krill dry powder through granulation, improves the fluidity of its particles, and is more conducive to fluid extraction. Since the particle size of the first granulation does not meet the particle size required for extraction, the present invention is made into particles that meet the characteristics of organic solvent fluid extraction through multiple extrusion rotary granulation. No auxiliary materials are added during the granulation process, and only the viscosity of lipids in the krill dry powder is relied on. Through extrusion and friction, small particles are agglomerated and turned into large particles. At the same time, during the friction movement of the particles, the temperature of the particles gradually increases. After multiple granulations, the temperature of the krill dry powder particles can also be raised to 40°C to 50°C, which is close to the temperature required by the subsequent extraction process, thereby improving the extraction efficiency.

[0045] In the present invention, as an optional embodiment, the preparation method of Antarctic krill oil comprises the following steps:

[0046] (1) Granulation: The Antarctic krill powder is subjected to extrusion rotary granulation for 3 to 5 times. After the last granulation, the temperature of the krill powder particles reaches 40 to 50° C., forming krill powder particles with good fluidity. The particle size of the krill powder particles is 4 to 8 mm.

[0047] (2) Noncritical fluid extraction: n-butane is added to the krill powder particles for extraction, the material-liquid mass ratio is 1:(4-6), the extraction pressure is 0.4-1.0 MPa, the extraction temperature is 30-45°C, and the stirring speed is 30-40 rpm; the extraction is allowed to stand for 30-60 min to obtain the n-butane extract;

[0048] (3) Vacuum limit n-butane removal: the n-butane extract is collected and transferred to an evaporator for evaporation, the vacuum degree in the evaporator is -0.5 to -0.01 Pa, the solution temperature in the evaporator is 50 to 60° C., the desolventizing time is 40 to 60 min, and the n-butane is evaporated and removed 1 to 3 times to obtain the Antarctic krill oil crude oil; the n-butane residual content in the Antarctic krill oil crude oil is ≤10 mg / kg;

[0049] (4) Deodorization of crude oil: The crude oil is introduced into a deodorization device and heated to a temperature of 35 to 65°C for 20 to 40 minutes. Nitrogen is introduced into the device from the bottom of the device to contact the crude oil in the device. The nitrogen introduction rate is 0.5 to 5 L / min. At the same time, the device is stirred to remove the odor. The stirring speed is 20 to 40 rpm. The device is maintained at a slight vacuum of -0.06 to -0.08 Pa and the temperature is maintained at 35 to 65°C. The nitrogen that absorbs the odor of krill oil is extracted from the top of the device. Taking 800 kg of crude Antarctic krill oil as an example, the entire deodorization process takes 40 to 50 minutes.

[0050] The present invention also provides Antarctic krill oil prepared by the preparation method.

[0051] The present invention also provides an application of the Antarctic krill oil in preparing food or medicine.

[0052] In the present invention, the types of the food or medicine are not particularly limited and can be conventionally selected according to actual needs. The Antarctic krill oil prepared by the present invention has the fresh and fragrant taste and aroma of shrimp, has no fishy smell, and the effective ingredients are fully retained, wherein the DHA content reaches 6.1g / 100g, and the EPA content reaches 10g / 100g, and can be used for the preparation of food or medicine.

[0053] 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.

[0054] In the following embodiments, unless otherwise specified, all of them are conventional methods.

[0055] Unless otherwise specified, the materials and reagents used in the following examples can be obtained from commercial sources.

[0056] Example 1

[0057] A method for removing the smell of Antarctic krill oil, the method comprising the following steps:

[0058] 800kg of Antarctic krill oil was introduced into the deodorization device, heated to 55°C, and stabilized for 30 minutes; nitrogen was introduced from the bottom of the device at a rate of 0.89L / min, and the stirring device was turned on to stir and deodorize at a speed of 30rpm. The vacuum degree in the device was maintained at -0.08Pa and the temperature was maintained at 55°C, and nitrogen was extracted from the top of the device. The entire deodorization process took 45 minutes.

[0059] The prepared Antarctic krill oil has no fishy smell and has the unique shrimp flavor and smell of krill oil.

[0060] Example 2

[0061] A method for removing the smell of Antarctic krill oil, the method being different from Example 1 in that the nitrogen introduction rate is 0.6 L / min and the entire deodorization process takes 50 minutes.

[0062] The prepared Antarctic krill oil has no fishy smell and has the unique shrimp flavor and smell of krill oil.

[0063] Example 3

[0064] A method for removing the smell of Antarctic krill oil, the method being different from Example 1 in that the nitrogen introduction rate is 1.2 L / min and the entire deodorization process takes 40 minutes.

[0065] The prepared Antarctic krill oil has no fishy smell and has the unique shrimp flavor and smell of krill oil.

[0066] Example 4

[0067] A method for removing the smell of Antarctic krill oil, the method being different from Example 1 in that a slight vacuum of -0.06 Pa is maintained in the device.

[0068] The prepared Antarctic krill oil has no fishy smell and has the unique shrimp flavor and smell of krill oil.

[0069] Example 5

[0070] A method for removing the odor of Antarctic krill oil. The method is different from Example 1 in that the crude Antarctic krill oil is introduced into a deodorizing device, and the temperature in the deodorizing device is kept at 50°C; when stirring to remove the odor, the temperature in the device is maintained at 50°C.

[0071] The prepared Antarctic krill oil has no fishy smell and has the unique shrimp flavor and smell of krill oil.

[0072] Example 6

[0073] A method for removing the odor of Antarctic krill oil. The method is different from Example 1 in that the crude Antarctic krill oil is introduced into a deodorizing device, and the temperature in the deodorizing device is kept at 60°C; when stirring to remove the odor, the temperature in the device is maintained at 60°C.

[0074] The prepared Antarctic krill oil has no fishy smell and has the unique shrimp flavor and smell of krill oil.

[0075] Example 7

[0076] A method for preparing Antarctic krill oil, the method comprising the following steps:

[0077] (1) Antarctic krill dry powder is subjected to extrusion rotary granulation, and the krill powder is bonded into a mass by heat generated by lipid viscosity friction, and granulation is performed 4 times in total. When the 4th granulation is completed, the temperature of the krill powder particles is 50° C., and the particle size of the krill powder particles after granulation is 6 mm;

[0078] (2) Noncritical fluid extraction: The Antarctic krill powder particles that have been granulated four times are transferred to an extraction tank, and n-butane is added to the tank for extraction. The material-liquid mass ratio is 1:6, the extraction pressure is 0.8 MPa, the extraction temperature is 38°C, and the stirring speed is 35 rpm. The n-butane extract is obtained by standing for 45 minutes.

[0079] (3) Vacuum limit de-butaneization: the n-butane extract is collected and transferred to an evaporator for evaporation. The vacuum degree in the evaporator is -0.1 Pa, the solution temperature in the evaporator is 55° C., the desolventizing time is 50 minutes, and the krill oil primary product is evaporated. After testing, the residual n-butane in the primary product is ≤300 mg / kg;

[0080] Vacuum debutane again: The primary product of krill oil is desolventized again at a vacuum degree of -0.1Pa and a temperature of 55°C for 50 minutes to obtain crude Antarctic krill oil; after testing, the residual amount of n-butane in the crude Antarctic krill oil is ≤1.0mg / kg;

[0081] (4) Deodorization of crude oil: 800 kg of crude oil is passed into Figure 1 The deodorizing tank body 1 of the deodorizing device is heated by a continuous temperature control jacket 3 to keep the crude oil temperature in the tank at 55°C for 30 minutes; nitrogen is introduced into the tank from a nitrogen inlet 9 at the bottom of the tank to contact the crude oil in the tank, and the nitrogen introduction rate is 0.89L / min. At the same time, the tank is stirred at a stirring speed of 30rpm. The tank is maintained at a slight vacuum of -0.08Pa and a temperature of 55°C by a screw vacuum pump unit 4; nitrogen that absorbs the fishy smell of krill oil is vacuum-extracted from a nitrogen exhaust port 8 at the top of the tank, and the extracted nitrogen is cooled and recovered by a cooling tower 5; the entire deodorizing process takes 45 minutes.

[0082] Antarctic krill oil is collected through the liquid outlet. The prepared Antarctic krill oil has no fishy smell, has the unique shrimp flavor and smell of krill oil, and has a reddish brown color. Referring to "GB 28404-2012 National Food Safety Standard Determination of α-linolenic acid, eicosapentaenoic acid, docosapentaenoic acid and docosahexaenoic acid in health foods", the effective ingredients in the crude Antarctic krill oil before and after deodorization were tested. The results showed that before deodorization, the DHA content in the crude Antarctic krill oil was 5.8g / 100g, and the EPA content was 8.8g / 100g; after deodorization, the DHA content in the Antarctic krill oil was 6.1g / 100g, and the EPA content was 10g / 100g. The deodorization process has basically no effect on the DHA and EPA content.

[0083] Example 8

[0084] A method for preparing Antarctic krill oil, the method differs from Example 7 in that in step (4), the crude oil temperature in the tank is kept at 45°C for 30 minutes; during deodorization, the temperature in the deodorization tank is maintained at 45°C.

[0085] It has a certain deodorizing effect. The prepared Antarctic krill oil has a slight fishy smell, and the deodorizing effect is worse than that under 55°C conditions. It has a certain krill oil-specific shrimp flavor and smell, and the visual color is reddish brown.

[0086] Example 9

[0087] A method for preparing Antarctic krill oil, the method differs from Example 7 in that in step (4), the crude oil temperature in the tank is kept at 65°C for 30 minutes; during deodorization, the temperature in the deodorization tank is maintained at 65°C.

[0088] The prepared Antarctic krill oil has no fishy smell, and its unique shrimp fresh smell is not as strong as that at 45°C and 55°C, and its taste is lighter, and its visual color becomes dark reddish brown.

[0089] Example 10

[0090] A method for preparing Antarctic krill oil, the method comprising the following steps:

[0091] (1) Antarctic krill dry powder is subjected to extrusion rotary granulation, and the krill powder is bonded into a mass by relying on the heat generated by lipid viscosity friction. The granulation is performed three times. When the third granulation is completed, the temperature of the krill powder particles is 40° C., and the particle size of the krill powder particles after granulation is 4 mm;

[0092] (2) Noncritical fluid extraction: The Antarctic krill powder particles that have been granulated three times are transferred to an extraction tank, and n-butane is added to the tank for extraction. The material-liquid mass ratio is 1:4, the extraction pressure is 0.5 MPa, the extraction temperature is 30°C, and the stirring speed is 30 rpm. The mixture is allowed to stand for 60 min to obtain an n-butane extract.

[0093] (3) Vacuum extreme n-butane removal: the n-butane extract is collected and transferred to an evaporator for evaporation. The vacuum degree in the evaporator is -0.5 Pa, the solution temperature in the evaporator is 50° C., and the desolventizing time is 40 minutes. The primary product of krill oil is evaporated;

[0094] Vacuum debutanization again: The primary product of krill oil is desolventized again at a vacuum degree of -0.5 Pa and a temperature of 50°C for 40 minutes to obtain crude Antarctic krill oil;

[0095] (4) Deodorization of crude oil: Same as Example 7.

[0096] The prepared Antarctic krill oil has no fishy smell, has the unique shrimp flavor and smell of krill oil, and has a reddish-brown color.

[0097] Embodiment 11

[0098] A method for preparing Antarctic krill oil, the method comprising the following steps:

[0099] (1) Antarctic krill dry powder is subjected to extrusion rotary granulation, and the krill powder is bonded into a mass by heat generated by lipid viscosity friction, and granulation is performed for 5 times. When the fifth granulation is completed, the temperature of the krill powder particles is 50° C., and the particle size of the krill powder particles after granulation is 8 mm;

[0100] (2) Noncritical fluid extraction: The Antarctic krill powder particles that have been granulated for 5 times are transferred to an extraction tank, and n-butane is added to the tank for extraction. The material-liquid mass ratio is 1:5, the extraction pressure is 0.6 MPa, the extraction temperature is 45°C, and the stirring speed is 40 rpm. The mixture is allowed to stand for 30 min to obtain an n-butane extract.

[0101] (3) Vacuum extreme n-butane removal: the n-butane extract is collected and transferred to an evaporator for evaporation. The vacuum degree in the evaporator is -0.05 Pa, the solution temperature in the evaporator is 60° C., and the desolventizing time is 60 minutes. The primary product of krill oil is evaporated;

[0102] Vacuum debutanization again: The primary product of krill oil is desolventized again at a vacuum degree of -0.05 Pa and a temperature of 60°C for 60 minutes to obtain crude Antarctic krill oil;

[0103] (4) Deodorization of crude oil: Same as Example 7.

[0104] The prepared Antarctic krill oil has no fishy smell, has the unique shrimp flavor and smell of krill oil, and has a reddish-brown color.

[0105] Comparative Example 1

[0106] A method for preparing Antarctic krill oil, the method being different from that of Example 7 in that:

[0107] (4) Deodorization of crude oil: Pass the crude oil into the deodorization tank, start the vacuum pump to reduce the system pressure, heat the deodorization tank, slowly heat the crude oil to 144°C, and pass nitrogen into the tank from the bottom of the tank to contact the crude oil in the tank. The nitrogen introduction rate is 2.1 mL / min, and the deodorization time is 3.5 h.

[0108] After being deodorized by nitrogen for a long time at high temperature, the prepared krill oil has been denatured and its color is egg yolk. The fluidity of the oil is similar to that of an egg after being stirred.

[0109] Comparative Example 2

[0110] A method for preparing Antarctic krill oil, the method being different from that of Example 7 in that:

[0111] (4) Removal of fishy smell from crude oil: After gassing under reduced pressure, preheat the crude oil to above 100°C and start introducing nitrogen. Adjust the nitrogen flow rate to stabilize it at 0.08 m / s. 3 / h later, the crude oil is rapidly heated to 210℃ and the deodorization time is 80min.

[0112] After being deodorized by nitrogen for a long time at high temperature, the prepared krill oil has been denatured and has an appearance similar to denatured protein and flocculent oil.

[0113] 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 the fishy smell of Antarctic krill oil, characterized in that: The deodorizing method comprises the following steps: The crude Antarctic krill oil is introduced into a deodorizing device, nitrogen is introduced from the bottom of the device, the deodorizing is stirred, and nitrogen is extracted from the top of the device; during the deodorizing, the vacuum degree in the device is maintained at -0.06 to -0.08 Pa and the temperature is maintained at 35 to 65°C.

2. The method for removing fishy smell according to claim 1, characterized in that: The crude Antarctic krill oil is passed into the deodorization device to stabilize the crude oil at a temperature of 35 to 65°C for 20 to 40 minutes.

3. The method for removing fishy smell according to claim 1, characterized in that: The nitrogen introduction rate is 0.5-5 L / min.

4. Use of the deodorization method according to any one of claims 1 to 3 in the preparation of Antarctic krill oil.

5. A method for preparing Antarctic krill oil, characterized in that: The preparation method comprises the following steps: The Antarctic krill powder is granulated to form krill powder particles; the krill powder particles are extracted with an organic solvent to obtain crude Antarctic krill oil; the crude Antarctic krill oil is deodorized by the deodorization method according to any one of claims 1 to 3 to obtain Antarctic krill oil.

6. The preparation method according to claim 5, characterized in that: The granulation is extrusion rotary granulation, and the number of granulation is 3 to 5 times.

7. The preparation method according to claim 5, characterized in that: The organic solvent includes n-butane or propane.

8. The preparation method according to claim 5, characterized in that: The extraction conditions include: extraction pressure of 0.4-1.0 MPa, extraction temperature of 30-45° C., and stirring speed of 30-40 rpm.

9. Antarctic krill oil prepared by the preparation method according to any one of claims 5 to 8.

10. Use of the Antarctic krill oil according to claim 9 in preparing food or medicine.

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