Deep processing and extraction method of krill oil

Abstract

The invention relates to a deep processing and extraction method of krill oil. S1, raw material pretreatment; s2, cell disruption; s3, performing enzymolysis treatment; s4, oil extraction; s5, desolventizing and refining; and S6, quality detection and packaging. The whole extraction process is reasonable in technological parameter and mild in operation condition, and nutritional ingredients such as Omega-3 fatty acid, phospholipid and astaxanthin in the krill oil can be reserved to the maximum extent. The obtained krill oil product has the characteristics of high purity and high quality, and has good market prospect and application value.

Description

Technical Field

[0001] The present invention relates to the technical field of utilization of marine biological resources, and more specifically, to a method for deep processing and extraction of krill oil. Background Art

[0002] Krill is a small crustacean that lives in the ocean. It is rich in krill oil, which has a variety of biological activities. Krill oil is rich in omega-3 fatty acids (including EPA and DHA), phospholipids, astaxanthin and other nutrients, which have many benefits for human health, such as regulating blood lipids, improving cognitive function, and enhancing immunity.

[0003] However, the existing krill oil extraction methods have some shortcomings, such as low extraction efficiency, low product purity, and easy destruction of some nutrients. Therefore, it is of great significance to develop a krill oil deep processing and extraction method that is efficient, high-purity, and can retain nutrients to the greatest extent. Summary of the invention

[0004] In order to overcome the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to overcome the problems of low extraction efficiency, low product purity, and easy destruction of some nutrients.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A method for deep processing and extraction of krill oil comprises the following steps:

[0007] S1. Raw material pretreatment: Select fresh krill, wash and remove impurities and salt, and then perform low-temperature drying;

[0008] S2. Cell disruption: The dried krill are disrupted by ultra-high pressure homogenization technology;

[0009] S3, enzymatic hydrolysis treatment: adding compound enzyme to the krill material after cell crushing, adjusting pH value and temperature to carry out enzymatic hydrolysis reaction, and performing enzyme inactivation treatment after the reaction is completed;

[0010] S4, oil extraction: extracting the enzymatically hydrolyzed krill oil using an organic solvent extraction method;

[0011] S5, desolventizing and refining: performing vacuum distillation to desolventize the organic solvent solution containing krill oil to obtain crude krill oil, and then refining the crude krill oil using molecular distillation technology;

[0012] S6. Quality inspection and packaging: The refined krill oil is quality inspected and packaged after passing the inspection.

[0013] In a preferred embodiment, in the raw material pretreatment, the low-temperature drying temperature is controlled between -20°C and -10°C, and the drying time is 2-4 hours.

[0014] In a preferred embodiment, in the cell disruption, the pressure of ultra-high pressure homogenization is 100-150 MPa, the process is circulated 2-3 times, and the material temperature is controlled at 10-15°C.

[0015] In a preferred embodiment, in the enzymatic hydrolysis treatment, the composite enzyme is composed of protease, phospholipase and cellulase in a mass ratio of 2:1:1, the amount of the composite enzyme added is 0.5%-1% of the mass of the krill material, the pH value is adjusted to 5.5-6.5, the enzymatic hydrolysis is carried out at a temperature of 40-50°C for 3-5 hours, the enzyme inactivation temperature is 80-90°C, and the enzyme inactivation time is 10-15 minutes.

[0016] In a preferred embodiment, in the oil extraction, the organic solvent is n-hexane, the volume mass ratio of n-hexane to krill material is 3-5:1 (mL / g), the stirring extraction time is 30-45 minutes, the centrifugal separation speed is 3000-4000r / min, and the centrifugation time is 10-15 minutes.

[0017] In a preferred embodiment, during the desolventizing and refining, the temperature of the reduced pressure distillation desolventizing is controlled at 40-50°C, the vacuum degree is -0.08-0.1MPa, and the operating conditions of the molecular distillation are: distillation temperature 120-150°C, vacuum degree 1-5Pa, feed rate 1-2mL / min, and scraping speed 200-300r / min.

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

[0019] 1. The present invention uses ultra-high pressure homogenization technology to break cells, which can effectively break krill cells and improve the oil extraction rate. Compared with traditional breaking methods, ultra-high pressure homogenization technology has the advantages of good breaking effect, simple operation, and little damage to nutrients.

[0020] 2. The use of compound enzymes in the enzymatic hydrolysis process can specifically decompose the protein, phospholipids and cellulose in krill, making it easier to release the oil, while increasing the content of phospholipids and other nutrients in krill oil. By controlling the enzymatic hydrolysis conditions, such as pH value, temperature and time, the activity of the enzyme can be maximized and the efficiency of enzymatic hydrolysis can be improved.

[0021] 3. Organic solvent extraction combined with vacuum distillation and molecular distillation technology can effectively remove impurities in krill oil and improve the purity of the product. Hexane as an extraction solvent has good solubility and selectivity, and can fully extract krill oil from the material. The vacuum distillation and molecular distillation process is carried out at a lower temperature, which can reduce the oxidation of oils and the loss of nutrients, and ensure the quality and stability of the product.

[0022] 4. The entire extraction process of the present invention has reasonable process parameters and mild operating conditions, which can retain the nutrients in krill oil to the greatest extent, such as Omega-3 fatty acids, phospholipids and astaxanthin, etc. The obtained krill oil product has the characteristics of high purity and high quality, and has good market prospects and application value. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] Embodiment 1

[0025] Raw material pretreatment

[0026] Select 100 kg of fresh krill and rinse them with clean water three times to remove impurities and salt on the surface.

[0027] The cleaned krill are placed in a low-temperature drying device and dried at -15°C for 3 hours to reduce the moisture content to below 10%.

[0028] Cell disruption

[0029] The dried krill was placed in an ultra-high pressure homogenizer, the pressure was set to 120 MPa, and the process was circulated twice, and the material temperature was controlled at 12°C.

[0030] Enzymatic treatment

[0031] 0.8 kg of complex enzyme (the mass ratio of protease, phospholipase and cellulase is 2:1:1) was added to the krill material after cell crushing, and the pH value of the material was adjusted to 6.0 with citric acid.

[0032] The material was placed in a constant temperature water bath and subjected to enzymatic hydrolysis at 45°C for 4 hours, during which the material was stirred every 30 minutes.

[0033] After the enzymatic hydrolysis reaction is completed, the material is heated to 85°C and maintained for 12 minutes to inactivate the enzyme.

[0034] Oil Extraction

[0035] 300 L of n-hexane was added to the enzyme-inactivated material, and the mixture was stirred and extracted for 40 minutes at a stirring speed of 120 r / min.

[0036] The extracted material was poured into a centrifuge and centrifuged at 3500 r / min for 12 minutes to separate the upper layer of n-hexane solution containing krill oil.

[0037] Desolventization and refining

[0038] The n-hexane solution containing krill oil is poured into a vacuum distillation device, and vacuum distillation is performed under the conditions of 45° C. and a vacuum degree of -0.09 MPa to desolventize, and the n-hexane solvent is recovered to obtain crude krill oil.

[0039] The crude krill oil was purified by molecular distillation at a distillation temperature of 130°C, a vacuum degree of 3Pa, a feed rate of 1.5mL / min, and a scraping speed of 250r / min to obtain a high-purity krill oil product.

[0040] Quality inspection and packaging

[0041] The refined krill oil was quality tested and the results showed that the krill oil content was 95%, the Omega-3 fatty acid content was 30%, the phospholipid content was 25%, the astaxanthin content was 0.5%, the acid value was 1.2 mg / g, and the peroxide value was 3 mmol / kg. All indicators met the relevant standards.

[0042] The krill oil that has passed the test is put into aluminum foil bags, 100 mL per bag, and sealed.

[0043] Embodiment 2

[0044] Raw material pretreatment

[0045] 80 kg of fresh krill were selected and rinsed with clean water for 4 times to remove impurities and salt on the surface.

[0046] The cleaned krill were placed in a low-temperature drying device and dried at -18°C for 2.5 hours to reduce the moisture content to below 8%.

[0047] Cell disruption

[0048] The dried krill was placed in an ultra-high pressure homogenizer, the pressure was set to 130 MPa, and the process was circulated for 3 times, and the material temperature was controlled at 10°C.

[0049] Enzymatic treatment

[0050] 0.6 kg of complex enzyme (the mass ratio of protease, phospholipase and cellulase is 2:1:1) was added to the krill material after cell crushing, and the pH value of the material was adjusted to 5.8 with phosphoric acid.

[0051] The material was placed in a constant temperature water bath and subjected to enzymatic hydrolysis at 48°C for 3.5 hours, during which the material was stirred every 25 minutes.

[0052] After the enzymatic hydrolysis reaction is completed, the material is heated to 82°C and maintained for 10 minutes to inactivate the enzyme.

[0053] Oil Extraction

[0054] 240 L of n-hexane was added to the material after the enzyme was inactivated, and the mixture was stirred and extracted for 35 minutes at a stirring speed of 130 r / min.

[0055] The extracted material was poured into a centrifuge and centrifuged at 3200 r / min for 13 minutes to separate the upper layer of n-hexane solution containing krill oil.

[0056] Desolventization and refining

[0057] The n-hexane solution containing krill oil is poured into a vacuum distillation device, and vacuum distillation is performed under the conditions of 42° C. and a vacuum degree of -0.08 MPa to desolventize, and the n-hexane solvent is recovered to obtain crude krill oil.

[0058] The crude krill oil was purified by molecular distillation at a distillation temperature of 140°C, a vacuum degree of 2Pa, a feed rate of 1.2mL / min, and a scraping speed of 280r / min to obtain a high-purity krill oil product.

[0059] Quality inspection and packaging

[0060] The refined krill oil was quality tested and the results showed that the krill oil content was 96%, the Omega-3 fatty acid content was 32%, the phospholipid content was 26%, the astaxanthin content was 0.6%, the acid value was 1.0 mg / g, and the peroxide value was 2.8 mmol / kg. All indicators met the relevant standards.

[0061] The krill oil that has passed the test is put into glass bottles, 500 mL per bottle, and sealed.

[0062] It can be seen from the above examples that the krill oil deep processing and extraction method of the present invention has good stability and repeatability, can effectively extract high-purity krill oil, and the product is rich in nutrients, which meets the market demand for high-quality krill oil.

[0063] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that, for those skilled in the art, the described embodiments can be modified in various ways without departing from the spirit and scope of the present invention. Therefore, the above description is illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for deep processing and extraction of krill oil, characterized in that: The steps include: S1. Raw material pretreatment: Select fresh krill, wash and remove impurities and salt, and then perform low-temperature drying; S2. Cell disruption: The dried krill are disrupted by ultra-high pressure homogenization technology; S3, enzymatic hydrolysis treatment: adding compound enzyme to the krill material after cell crushing, adjusting pH value and temperature to carry out enzymatic hydrolysis reaction, and performing enzyme inactivation treatment after the reaction is completed; S4, oil extraction: extracting the enzymatically hydrolyzed krill oil using an organic solvent extraction method; S5, desolventizing and refining: performing vacuum distillation to desolventize the organic solvent solution containing krill oil to obtain crude krill oil, and then refining the crude krill oil using molecular distillation technology; S6. Quality inspection and packaging: The refined krill oil is quality inspected and packaged after passing the inspection.

2. The method for deep processing and extraction of krill oil according to claim 1, characterized in that: In the raw material pretreatment, the low-temperature drying temperature is controlled between -20°C and -10°C, and the drying time is 2-4 hours.

3. The method for deep processing and extraction of krill oil according to claim 1, characterized in that: In the cell disruption, the pressure of ultra-high pressure homogenization is 100-150 MPa, the process is circulated 2-3 times, and the material temperature is controlled at 10-15°C.

4. The method for deep processing and extraction of krill oil according to claim 1, characterized in that: In the enzymatic hydrolysis treatment, the compound enzyme is composed of protease, phospholipase and cellulase in a mass ratio of 2:1:1, the added amount of the compound enzyme is 0.5%-1% of the mass of the krill material, the pH value is adjusted to 5.5-6.5, the enzymatic hydrolysis is carried out at a temperature of 40-50°C for 3-5 hours, the enzyme inactivation temperature is 80-90°C, and the enzyme inactivation time is 10-15 minutes.

5. The method for deep processing and extraction of krill oil according to claim 1, characterized in that: In the oil extraction, the organic solvent is n-hexane, the volume mass ratio of n-hexane to krill material is 3-5:1 (mL / g), the stirring extraction time is 30-45 minutes, the centrifugal separation speed is 3000-4000r / min, and the centrifugal time is 10-15 minutes.

6. The method for deep processing and extraction of krill oil according to claim 1, characterized in that: During the desolventizing and refining, the temperature of the reduced pressure distillation desolventizing is controlled at 40-50°C, the vacuum degree is -0.08-0.1MPa, and the operating conditions of the molecular distillation are: distillation temperature 120-150°C, vacuum degree 1-5Pa, feed rate 1-2mL / min, and scraping speed 200-300r / min.