Low-acid-value krill oil and preparation method thereof

Abstract

The invention relates to the technical field of food science, in particular to low-acid-value krill oil and a preparation method thereof.The preparation method comprises the following steps that S1, firstly, krill is cleaned, shelled and dried and then smashed into powder; s2, putting the krill powder into a solvent, and carrying out primary extraction to obtain an extracting solution; s3, performing grease separation on the primary extracting solution through a separator; s4, adding glycerol into the crude krill oil, and enabling the glycerol to react with the free fatty acid to generate glyceride; s5, glyceride is subjected to refining treatment, and refined krill oil is obtained; s6, placing the refined krill oil in a vacuum environment for dehydration treatment; s7, the obtained low-acid-value krill oil is subjected to sterile packaging and sealed storage, and a finished product is obtained. By optimizing the process steps, the acid value of the krill oil is remarkably reduced, the quality and the stability of the krill oil are improved, and the method is suitable for large-scale industrial production and meets the requirements of the market on high-quality krill oil.

Description

Technical Field

[0001] The invention relates to the field of food science and technology, and in particular to a low-acid krill oil and a preparation method thereof. Background Art

[0002] Krill oil is a kind of oil extracted from krill. Because it is rich in ω-3 fatty acids, antioxidants and other bioactive ingredients, it has gained wide attention and application in the field of health food and medicine in recent years. Krill oil has many health benefits such as anti-inflammatory, cardiovascular protection, and improving immunity. The market demand is increasing year by year. However, the traditional krill oil extraction process usually leads to a high acid value in krill oil, which not only affects the taste of krill oil, but also accelerates its oxidation and deterioration, shortening the shelf life of the product. Krill oil with high acid value has poor stability during storage and transportation, which is easy to cause quality problems, limiting its wide application.

[0003] At present, there is an urgent need for high-quality, low-acid krill oil in the market. However, it is difficult to effectively reduce the acid value of krill oil in large-scale production with the existing technology. Traditional acid reduction methods are usually inefficient and difficult to meet the requirements of industrial production. In view of the above problems, the present invention proposes a low-acid krill oil and a preparation method thereof. By optimizing the process steps of raw material processing, extraction, and refining, the acid value of krill oil is effectively reduced, and its quality and stability are improved to meet the market demand for high-quality krill oil. This is of great significance for improving the market competitiveness of krill oil and expanding its application scope. Summary of the invention

[0004] Based on the above purpose, the present invention provides a low acid value krill oil and a preparation method thereof.

[0005] A low acid value krill oil, comprising krill oil and glycerol; wherein the components are as follows according to mass percentage: krill oil accounts for 94-96%; glycerol accounts for 4-6%.

[0006] A method for preparing low acid value krill oil comprises the following steps: S1: First, clean and shell the krill, dry them, and crush them into powder; S2: placing the krill powder in a solvent for preliminary extraction to obtain an extract; S3: separating the oil from the primary extract by a separator to obtain crude krill oil; S4: adding glycerol to the crude krill oil, stirring evenly and then heating to allow the glycerol to react with free fatty acids to form glycerides; S5: refining the glyceride to obtain refined krill oil; S6: dehydrating the refined krill oil under vacuum to remove residual water; S7: The obtained low acid value krill oil is aseptically packaged and sealed for storage to obtain a finished product.

[0007] Furthermore, the krill powder in S1 is dried at a temperature of 50-60° C., dried for 4-6 hours, and has a particle size of 0.1-0.5 mm after crushing.

[0008] Furthermore, the solvent in S2 is ethanol, the mass ratio of ethanol to krill powder is 3:1, the extraction temperature is 60-70° C., and the extraction time is 1-2 hours.

[0009] Furthermore, the rotation speed of the separator in S3 is 3000-5000 rpm, and the separation time is 30-60 minutes.

[0010] Furthermore, the heating temperature in S4 is 50-60° C., and the heating time is 1-2 hours.

[0011] Furthermore, the specific steps of the refining treatment in S5 include deacidification, decolorization and deodorization, wherein: The deacidification agent is activated clay, the usage amount is 2-4% of the weight of krill oil, the deacidification temperature is 70-80℃, and the time is 30-60 minutes; The decolorizing agent is activated carbon, the usage amount is 1-3% of the weight of krill oil, the decolorizing temperature is 80-90℃, and the time is 20-40 minutes; The deodorization process is carried out under vacuum conditions at 150-180°C for 1-2 hours.

[0012] Furthermore, the vacuum degree of the vacuum dehydration in S6 is 0.08-0.1 MPa, the temperature is 60-70° C., and the time is 1-2 hours.

[0013] Beneficial effects of the present invention: The present invention successfully solves the problem of high acidity of krill oil in the prior art by optimizing the process steps of raw material processing, extraction, refining, etc. The acidity of krill oil prepared by the method of the present invention is significantly reduced, and the biologically active ingredients such as ω-3 fatty acids and antioxidants rich in krill oil are maintained, thereby improving the taste and quality of the product. The krill oil with low acidity has better stability during storage and transportation, and has a longer shelf life, thereby meeting the market demand for high-quality krill oil.

[0014] The present invention can stably produce high-quality krill oil with low acid value by rationally allocating various components and controlling the specific conditions of various process steps, thus providing strong support for the wide application of krill oil, which not only improves the market competitiveness of the product, but also provides better quality raw materials for the fields of health food and medicine. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 The figure is a schematic diagram of the process for preparing low acid value krill oil according to an embodiment of the present invention. DETAILED DESCRIPTION

[0017] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0018] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0019] Example 1 like Figure 1 As shown, a low acid value krill oil and a preparation method thereof include krill oil and glycerol; wherein the components are as follows in terms of mass percentage: krill oil accounts for 95%; glycerol accounts for 5%.

[0020] A method for preparing low acid value krill oil comprises the following steps: S1: First, clean and shell the krill, dry them, and crush them into powder; S2: placing the krill powder in a solvent for preliminary extraction to obtain an extract; S3: separating the oil from the primary extract by a separator to obtain crude krill oil; S4: adding glycerol to the crude krill oil, stirring evenly and then heating to allow the glycerol to react with free fatty acids to form glycerides; S5: refining the glyceride to obtain refined krill oil; S6: dehydrating the refined krill oil under vacuum to remove residual water; S7: The obtained low acid value krill oil is aseptically packaged and sealed for storage to obtain a finished product.

[0021] The krill powder in S1 was dried at 55°C for 5 hours, and had a particle size of 0.3 mm after pulverization.

[0022] The solvent in S2 is ethanol, the mass ratio of ethanol to krill powder is 3:1, the extraction temperature is 65°C, and the extraction time is 1.5 hours.

[0023] The rotation speed of the separator in S3 is 4000 rpm, and the separation time is 45 minutes.

[0024] The heating temperature in S4 was 55° C. and the heating time was 1.5 hours.

[0025] The specific steps of the refining treatment in S5 include deacidification, decolorization and deodorization, wherein: The deacidification agent is activated white clay, the usage amount is 3% of the weight of krill oil, the deacidification temperature is 75°C, and the time is 45 minutes; The decolorizing agent is activated carbon, the usage amount is 2% of the weight of krill oil, the decolorizing temperature is 85°C, and the time is 30 minutes; The deodorization process was carried out under vacuum conditions at 170°C for 1.5 hours.

[0026] The vacuum degree of vacuum dehydration in S6 is 0.09 MPa, the temperature is 65°C, and the time is 1.5 hours.

[0027] Example 2 Preparation of raw materials, by mass percentage: krill oil accounts for 96%; glycerol accounts for 4%.

[0028] The specific preparation process is as follows: S1: First, the krill were cleaned and shelled. Then, the krill were dried at 50°C for 4 hours. After drying, the krill were crushed into powder with a particle size of 0.1 mm to prepare for the next extraction step. S2: The dried krill powder was mixed with ethanol in a mass ratio of 3:1 and extracted at 60°C for 1 hour to maximize the extraction rate of krill oil; S3: passing the extract through a separator to separate oil from fat, wherein the speed of the separator is set to 3000 rpm and the separation time is 30 minutes. This step is to separate crude krill oil to prepare for subsequent glyceride esterification; S4: mixing the obtained crude krill oil with glycerol in an appropriate proportion, and then heating at a temperature of 50° C. for 1 hour, during which the glycerol reacts with free fatty acids to form glycerides; S5: The refining process includes three sub-steps: deacidification, decolorization and deodorization. First, deacidification is performed using activated clay at 2% by weight of krill oil at a temperature of 70°C for 30 minutes. Next, decolorization is performed using activated carbon at 1% by weight of krill oil at a temperature of 80°C for 20 minutes. Finally, the deodorization process is performed under vacuum conditions at 150°C for 1 hour. S6: The refined krill oil is placed in a vacuum environment for dehydration treatment. The vacuum degree is set to 0.08 MPa, the temperature is 60°C, and the duration is 1 hour. This step is to remove residual water in the oil to ensure the stability and quality of the product. S7: Finally, the obtained low acid value krill oil is aseptically packaged and sealed for storage to obtain a finished product.

[0029] Example 3 Preparation of raw materials, by mass percentage: krill oil accounts for 94%; glycerol accounts for 6%.

[0030] The specific preparation process is as follows: S1: First, the krill are cleaned and shelled. Then, the krill are dried at 60°C for 6 hours. After drying, the krill are crushed into powder with a particle size of 0.5 mm to prepare for the next extraction; S2: The dried krill powder was mixed with ethanol in a mass ratio of 3:1 and extracted at 70°C for 2 hours to maximize the extraction rate of krill oil; S3: passing the extract through a separator to separate oil from fat, wherein the speed of the separator is set to 5000 rpm and the separation time is 60 minutes. This step is to separate crude krill oil to prepare for subsequent glyceride esterification; S4: mixing the obtained crude krill oil with glycerol in an appropriate proportion, and then heating at a temperature of 60° C. for 2 hours, during which the glycerol reacts with free fatty acids to form glycerides; S5: The refining process includes three sub-steps: deacidification, decolorization and deodorization. First, deacidification is performed using activated clay at 4% by weight of the krill oil at a temperature of 80°C for 60 minutes. Next, decolorization is performed using activated carbon at 3% by weight of the krill oil at a temperature of 90°C for 40 minutes. Finally, the deodorization process is performed under vacuum conditions at 180°C for 2 hours. S6: Dehydrating the refined krill oil in a vacuum environment with a vacuum degree of 0.1 MPa, a temperature of 70°C and a duration of 2 hours. This step is intended to remove residual water in the oil and ensure the stability and quality of the product. S7: Finally, the obtained low acid value krill oil is aseptically packaged and sealed for storage to obtain a finished product.

[0031] Table 1 Comparison of performance parameters of finished products Test items Example 1 Example 2 Example 3 Acid value (mgKOH / g oil) 0.5 0.7 0.6 Peroxide value (meq / kg oil) 5 8 6 Color (Lovibond color palette) 1.2 Y + 0.1 R 1.8 Y + 0.2 R 1.5 Y + 0.15 R Vitamin E content (mg / kg) 120 100 110 Total antioxidant capacity 95% 85% 90% Moisture and volatile matter content (%) 0.05 0.08 0.07 It can be seen from Table 1 above that Example 1 performs well in all key performance indicators. Specifically, the acid value is low, indicating that the degree of oxidation of the oil is low and is more suitable for long-term storage; the peroxide value shows that the oil of Example 1 has the best antioxidant stability and strong resistance to air and light; the color is lighter, more popular with consumers, and indicates that the oil maintains good quality during the processing; the vitamin E content is the highest in Example 1, which is very important for improving the nutritional value and health care function of the product; the total antioxidant capacity is high, which means that the oxidation process of the product can be more effectively delayed and the shelf life can be extended; the moisture and volatile content are the lowest, indicating that the product is more pure and the oil processing technology is more refined.

[0032] In summary, Example 1 provides an optimized preparation method, which can produce high-quality low-acid krill oil with better market competitiveness and consumer acceptance.

[0033] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A low acid value krill oil, characterized in that: It includes krill oil and glycerin; the weight percentage of each component is as follows: krill oil accounts for 94-96%; glycerin accounts for 4-6%.

2. The method for preparing a low acid value krill oil according to any one of claim 1, characterized in that: The following steps are involved: S1: First, clean and shell the krill, dry them, and crush them into powder; S2: placing the krill powder in a solvent for preliminary extraction to obtain an extract; S3: separating the oil from the primary extract by a separator to obtain crude krill oil; S4: adding glycerol to the crude krill oil, stirring evenly and then heating to allow the glycerol to react with free fatty acids to form glycerides; S5: refining the glyceride to obtain refined krill oil; S6: dehydrating the refined krill oil under vacuum to remove residual water; S7: The obtained low acid value krill oil is aseptically packaged and sealed for storage to obtain a finished product.

3. The method for preparing a low acid value krill oil according to claim 3, characterized in that: The krill powder in S1 has a drying temperature of 50-60° C., a drying time of 4-6 hours, and a particle size of 0.1-0.5 mm after crushing.

4. The method for preparing a low acid value krill oil according to claim 3, characterized in that: The solvent in S2 is ethanol, the mass ratio of ethanol to krill powder is 3:1, the extraction temperature is 60-70° C., and the extraction time is 1-2 hours.

5. The method for preparing a low acid value krill oil according to claim 3, characterized in that: The rotation speed of the separator in S3 is 3000-5000 rpm, and the separation time is 30-60 minutes.

6. The method for preparing low acid value krill oil according to claim 3, characterized in that: The heating temperature in S4 is 50-60° C., and the heating time is 1-2 hours.

7. The method for preparing low acid value krill oil according to claim 3, characterized in that: The specific steps of the refining treatment in S5 include deacidification, decolorization and deodorization, wherein: The deacidification agent is activated clay, the usage amount is 2-4% of the weight of krill oil, the deacidification temperature is 70-80℃, and the time is 30-60 minutes; The decolorizing agent is activated carbon, the usage amount is 1-3% of the weight of krill oil, the decolorizing temperature is 80-90℃, and the time is 20-40 minutes; The deodorization process is carried out under vacuum conditions at 150-180°C for 1-2 hours.

8. The method for preparing low acid value krill oil according to claim 3, characterized in that: The vacuum degree of the vacuum dehydration in S6 is 0.08-0.1 MPa, the temperature is 60-70° C., and the time is 1-2 hours.

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