A stabilized dha nanoemulsion and method of making same

Abstract

The application relates to a stabilized DHA nanoemulsion and a preparation method thereof, and belongs to the technical field of food processing. The main components of the stabilized DHA nanoemulsion include DHA oil, oil-soluble emulsifier, water-soluble emulsifier, stabilizer, antioxidant, amino acid, antioxidant synergist and deionized water. The preparation method comprises the following steps: preparing an oil phase and an oil solution, preparing a water phase, and mixing the oil solution and the water phase to obtain a finished product. The stabilized DHA nanoemulsion prepared by the application is clear and transparent, has good flavor, can be stored for a long time under normal temperature and high-temperature environment, and has the advantages of strong emulsion stability, hydrophilicity and solubility.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of food processing, and particularly relates to a stabilized DHA nanoemulsion and a preparation method thereof. BACKGROUND

[0002] DHA (docosahexaenoic acid, C 22 H 32 O2) belongs to Omega-3 polyunsaturated fatty acids, commonly known as brain gold, is one of the main components of nerve cell growth and maintaining nervous system function, and is an important constituent of the brain and retina, accounting for 97% and 93% of the total Omega-3 fatty acids contained in the brain and retina, respectively. Although DHA can be generated from alpha-linolenic acid in the body, the production is low, and it still needs to be supplemented through food. The benefits of DHA to human health are not limited to the early life, but throughout the life cycle. Increasing the intake of DHA by the human body can reduce the risk of chronic diseases such as cardiovascular diseases and inflammatory bowel diseases, and plays an important role in maintaining the healthy level of blood lipids (triglycerides), reducing blood pressure, and preventing Alzheimer's disease.

[0003] The current main sources of DHA are deep sea fish oil and algae, but due to the fishy smell, water immiscibility, difficulty in direct intake and the like, the application of DHA products is limited. First, DHA contains multiple unsaturated double bonds and five active methylene groups, so it is extremely susceptible to external factors such as light, oxygen, high temperature and metal ions, thereby causing oxidation reaction and rancidity, producing strong fishy smell and rancid smell, and generating peroxides harmful to the human body. Second, DHA is a highly hydrophobic molecule with low water solubility, and cannot be introduced into most water-based foods such as liquid milk, juice, sauce and the like. Finally, after DHA enters the human body, it successively passes through the stomach and small intestine, although the target absorption organ is the small intestine of the human body, but often the original physiological activity is reduced or even lost before being digested and absorbed by the small intestine, and it cannot maximize its function in the human body. Therefore, how to improve the stability, hydrophilicity and solubility of DHA, improve its utilization efficiency in the human body, and better exert its physiological efficacy, has become a problem urgently to be solved for the development of functional DHA.

[0004] The DHA algal oil / fish oil soft capsule products that have been commercialized to a certain extent alleviate the defects of DHA oil caused by oxidation, but for children and the elderly and other groups, it is less convenient to take, the taste is poor, and the absorption rate is low. Although microencapsulation of DHA oil can embed the active ingredients of DHA to protect them from adverse factors, the production process is complicated and the production rate is poor, and the capsule product is also prone to deterioration in the high-temperature process. In addition, during the storage of the DHA oil capsule product, there are few types of capsules that can be used in the fields of food and feed.

[0005] Emulsion is a transparent or translucent stable system composed of oil, water, surfactant and other appropriate proportions, and is divided into O / W and W / O two types according to the dispersion of oil and water, and is widely used in food, medicine and other fields. The emulsion generally has two phases, one phase is water or aqueous solution, and the other phase is an organic liquid or microparticle which is not miscible with water, such as oil, fat-soluble vitamins, etc. The preparation process of ordinary emulsion is simple, and the cost is low, but the product is extremely unstable under environmental pressure, and is not suitable for embedding DHA oil. Nano-emulsion is a transparent or translucent thermodynamic stable system with a particle size of 50-500 nm, which can load high content of DHA oil as a nano-scale oil transmission system, greatly mask the original smell of DHA oil, improve the physicochemical stability and in vivo and in vitro digestion characteristics of DHA, and play a relatively ideal protective effect on DHA. However, there are few studies on embedding DHA oil by nano-emulsion in the prior art, which cannot meet the application requirements in food, feed, medicine and other aspects. SUMMARY

[0006] The purpose of the present application is to provide a stabilized DHA nano-emulsion and a preparation method thereof, so as to solve the problems of easy deterioration of DHA, limited product application, insufficient emulsion stability, hydrophilicity and solubility in the prior art.

[0007] In order to achieve the above-mentioned purpose of the application, the present application provides the following technical solutions:

[0008] The present application provides a stabilized DHA nano-emulsion, which comprises the following components in mass fraction: DHA oil 1-50 parts, oil-soluble emulsifier 0.1-40 parts, water-soluble emulsifier 0.1-40 parts, stabilizer 0.2-30 parts, antioxidant 0.1-10 parts, amino acid 0.1-10 parts, antioxidant synergist 0.01-3 parts and deionized water 0.5-38 parts.

[0009] Preferably, the DHA oil is seaweed oil and / or fish oil.

[0010] Preferably, the oil-soluble emulsifier comprises one or more of lecithin, citric acid fatty acid glyceride, diacetyl tartaric acid mono / diglyceride, polyglycerol ricinoleate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate, sodium stearoyl lactate and calcium stearoyl lactate.

[0011] Preferably, the water-soluble emulsifier comprises one or more of sucrose ester, polyglycerol fatty acid ester, sorbitan monolaurate, sorbitan monopalmitate, Tween 20, Tween 60, Tween 80 and caprylocaproyl glycerides.

[0012] Preferably, the stabilizer comprises one or more of trehalose, pullulan, lactose, fructooligosaccharide, glucose, soybean polysaccharide, cyclodextrin, sorbitol, maltitol, erythritol, xylitol and mannitol.

[0013] Preferably, the antioxidant comprises one or more of gamma-oryzanol, bamboo leaf antioxidant, tea polyphenol, licorice antioxidant, grape seed extract, rosemary extract and gallic acid.

[0014] Preferably, the amino acid comprises one or more of lysine, glutamic acid, histidine, arginine, phenylalanine, alanine, leucine, isoleucine, methionine, proline, tryptophan, valine, cysteine, glycine, asparagine, serine, threonine, glutamine, tyrosine and aspartic acid.

[0015] Preferably, the antioxidant synergist comprises one or more of citric acid, EDTA, tartaric acid, phosphoric acid, tannic acid, malic acid, phytic acid and ascorbic acid.

[0016] Preferably, the particle size of the stabilized DHA nanoemulsion is less than 200 nm.

[0017] The present application also provides a method for preparing the stabilized DHA nanoemulsion, comprising the following steps:

[0018] (1) mixing DHA oil and antioxidant to obtain an oil phase;

[0019] (2) mixing oil-soluble emulsifier, water-soluble emulsifier and the oil phase to obtain an oil solution;

[0020] (3) mixing stabilizer, amino acid, antioxidant synergist and deionized water to obtain an aqueous phase;

[0021] (4) mixing the oil solution and the aqueous phase, stirring, and incubating to obtain a stabilized DHA nano solution;

[0022] Preferably, the temperature of the mixing in steps (1)-(4) is independently 40-60℃.

[0023] Preferably, the mixing time in steps (1)-(2) is independently 5-15 min.

[0024] Preferably, the mixing time in step (4) is 20-40 min, the incubation temperature is 70-80℃, and the incubation time is 25-35 min.

[0025] The present application has the following technical effects and advantages:

[0026] The application improves the emulsion stability by preparing the stable DHA nanoemulsion with a particle size less than 100 nm through compounding specific oil-soluble emulsifiers and water-soluble emulsifiers in a certain proportion; the use of polysaccharide stabilizers can improve the emulsion stability and reduce the occurrence of delamination or precipitation; the compounding use of antioxidants, antioxidant synergists and amino acids can enhance the antioxidant effect of the stable DHA nanoemulsion, prolong the emulsion storage time and avoid the occurrence of rancid taste;

[0027] The prepared stable DHA nanoemulsion is clear and transparent, not emulsion-breaking, has good flavor, high bioavailability, strong emulsion stability, hydrophilicity and solubility, and can be stored for a long time at room temperature and high temperature, thereby solving the problems of easy deterioration of DHA and limited application of products;

[0028] The preparation method of the stable DHA nanoemulsion is simple in process and low in cost, and the nano-sized stable DHA microemulsion can be prepared without the aid of high-speed shearing, homogenization, ultrasonic and other technical means. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The particle size determination results of the stable DHA nanoemulsion prepared in Example 1 are shown in the figure, wherein the horizontal coordinate represents the emulsion particle size, and the vertical coordinate represents the particle size percentage content;

[0030] Figure 2 The particle size determination results of the stable DHA nanoemulsion prepared in Example 2 are shown in the figure, wherein the horizontal coordinate represents the emulsion particle size, and the vertical coordinate represents the particle size percentage content;

[0031] Figure 3 The particle size determination results of the stable DHA nanoemulsion prepared in Example 3 are shown in the figure, wherein the horizontal coordinate represents the emulsion particle size, and the vertical coordinate represents the particle size percentage content;

[0032] Figure 4 The particle size determination results of the DHA nanoemulsion prepared in Comparative Example 1 are shown in the figure, wherein the horizontal coordinate represents the emulsion particle size, and the vertical coordinate represents the particle size percentage content;

[0033] Figure 5 The particle size determination results of the DHA nanoemulsion prepared in Comparative Example 2 are shown in the figure, wherein the horizontal coordinate represents the emulsion particle size, and the vertical coordinate represents the particle size percentage content;

[0034] Figure 6 The particle size determination results of the DHA nanoemulsion prepared in Comparative Example 3 are shown in the figure, wherein the horizontal coordinate represents the emulsion particle size, and the vertical coordinate represents the particle size percentage content;

[0035] Figure 7The results of CDM value determination of the stabilized DHA nanoemulsion prepared in Example 1 are shown in the figure, in which the horizontal coordinate represents time, and the two vertical coordinates represent conductivity and second derivative, respectively;

[0036] Figure 8 The results of CDM value determination of the stabilized DHA nanoemulsion prepared in Example 2 are shown in the figure, in which the horizontal coordinate represents time, and the two vertical coordinates represent conductivity and second derivative, respectively;

[0037] Figure 9 The results of CDM value determination of the DHA nanoemulsion prepared in Comparative Example 4 are shown in the figure, in which the horizontal coordinate represents time, and the two vertical coordinates represent conductivity and second derivative, respectively;

[0038] Figure 10 The results of CDM value determination of the DHA nanoemulsion prepared in Comparative Example 5 are shown in the figure, in which the horizontal coordinate represents time, and the two vertical coordinates represent conductivity and second derivative, respectively. DETAILED DESCRIPTION

[0039] The present application provides a stabilized DHA nanoemulsion, which comprises the following components in mass fraction: 1-50 parts of DHA oil, preferably 20-40 parts, and further preferably 30 parts; 0.1-40 parts of oil-soluble emulsifier, preferably 5-20 parts, and further preferably 7 parts; 0.1-40 parts of water-soluble emulsifier, preferably 15-25 parts, and preferably 21 parts; 0.2-30 parts of stabilizer, preferably 5-20 parts, and further preferably 10 parts; 0.1-10 parts of antioxidant, preferably 0.5-2 parts, and further preferably 0.8 parts; 0.1-10 parts of amino acid, preferably 0.5-2 parts, and further preferably 1 part; 0.01-3 parts of antioxidant synergist, preferably 0.1-0.5 parts, and further preferably 0.2 parts; and 0.5-38 parts of deionized water, preferably 10-30 parts, and further preferably 30 parts.

[0040] In the present application, the DHA oil is algal oil and / or fish oil, and preferably fish oil.

[0041] In the present application, the oil-soluble emulsifier comprises one or more of lecithin, citric acid fatty acid glyceride, diacetyl tartaric acid mono / diglyceride, polyglycerol ricinoleate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate, sodium stearoyl lactate and calcium stearoyl lactate, and preferably citric acid fatty acid glyceride.

[0042] In the present application, the water-soluble emulsifier comprises one or more of sucrose ester, polyglycerol fatty acid ester, sorbitan monolaurate, sorbitan monopalmitate, Tween 20, Tween 60, Tween 80 and caprylocaproyl glycerides, and preferably caprylocaproyl glycerides.

[0043] In the present application, the stabilizer comprises one or more of trehalose, pullulan, lactose, fructooligosaccharide, glucose, soybean polysaccharide, cyclodextrin, sorbitol, maltitol, erythritol, xylitol and mannitol, preferably trehalose.

[0044] In the present application, the antioxidant comprises one or more of γ-oryzanol, bamboo leaf antioxidant, tea polyphenol, licorice antioxidant, grape seed extract, rosemary extract and gallic acid, preferably γ-oryzanol and bamboo leaf antioxidant.

[0045] In the present application, the amino acid comprises one or more of lysine, glutamic acid, histidine, arginine, phenylalanine, alanine, leucine, isoleucine, methionine, proline, tryptophan, valine, cysteine, glycine, asparagine, serine, threonine, glutamine, tyrosine and aspartic acid, preferably lysine.

[0046] In the present application, the antioxidant synergist comprises one or more of citric acid, EDTA, tartaric acid, phosphoric acid, tannic acid, malic acid, phytic acid and ascorbic acid, preferably malic acid.

[0047] In the present application, the particle size of the stabilized DHA nanoemulsion is <200 nm.

[0048] The present application also provides a preparation method of the stabilized DHA nanoemulsion, comprising the following steps:

[0049] (1) mixing DHA oil and antioxidant to obtain an oil phase;

[0050] (2) mixing oil-soluble emulsifier, water-soluble emulsifier and the oil phase to obtain an oil solution;

[0051] (3) mixing stabilizer, amino acid, antioxidant synergist and deionized water to obtain an aqueous phase;

[0052] (4) mixing the oil solution and the aqueous phase, stirring, and incubating to obtain a stabilized DHA nano solution;

[0053] In the present application, the temperature of the mixing in steps (1)-(4) is independently 40-60℃, preferably 50℃;

[0054] In the present application, the mixing time in steps (1)-(2) is independently 5-15 min, preferably 10 min;

[0055] In the present application, the mixing time in step (4) is 20-40 min, preferably 30 min; the incubation temperature is 70-80℃, preferably 75℃; and the incubation time is 25-35 min, preferably 30 min.

[0056] In the present application, the determination method of the DHA content of the stabilized DHA nanoemulsion is detected according to GB 5009.168-2016 Determination of fatty acids in foods.

[0057] In the present application, the determination method of the particle size of the stabilized DHA nanoemulsion is: the stabilized DHA nanoemulsion is mixed with hexane at a volume ratio of 5-15 μL: 1-3 mL, and then the determination is carried out, the volume ratio of the stabilized DHA nanoemulsion to hexane is preferably 5 μL: 1 mL, and the determination is preferably carried out using a Zetasizer Nano ZS nanoparticle size analyzer; the determination temperature is 10-30℃, preferably 20℃; when determining, the DHA nanoemulsion needs to be balanced for 3-5 min after mixing with hexane, preferably 4 min; the determination angle is 160°-180°, preferably 173°.

[0058] In the present application, the determination method of the CDM value of the stabilized DHA nanoemulsion is to use a Rancimat CDM tester to determine, the added amount of the stabilized DHA nanoemulsion is 1-5 g, preferably 3 g; the water added amount is 50-100 mL, preferably 70 mL; the air blowing amount is 10-30 L / h, preferably 20 L / h; the determination temperature is 80-100℃, preferably 96℃.

[0059] The technical solutions provided by the present application will be described in detail below in combination with the embodiments, but they should not be understood as limiting the scope of protection of the present application.

[0060] Example 1

[0061] Take 30 g of fish oil, 0.5 g of γ-oryzanol and 0.3 g of bamboo leaf antioxidant and mix them under a 50℃ water bath for 10 min to obtain an oil phase; add 7 g of citric acid fatty acid glyceride and 21 g of caprylocaproyl macrogolglycerides to the oil phase and mix them under a 50℃ water bath for 10 min to obtain an oil solution; take 10 g of trehalose, 1 g of lysine, 0.2 g of malic acid and 30 mL of deionized water and mix them under a 50℃ water bath, and then dissolve to obtain an aqueous phase; slowly add the aqueous phase to the oil solution and stir until uniform and transparent, then continue to stir at 50℃ for 30 min after the addition is completed, and then incubate at 75℃ for 30 min to obtain a stabilized DHA nanoemulsion.

[0062] Example 2

[0063] Take 30 g fish oil, 0.5 g tea polyphenol and 0.3 g rosemary extract in 50℃ water bath for 10 min, get oil phase; In the oil phase, add 13 g polyglyceryl ricinoleate and 15 g Tween 60, mix in 50℃ water bath for 10 min, get oil solution; Take 10 g soybean polysaccharide, 1 g alanine, 0.2 g phytic acid and 30 mL deionized water in 50℃ water bath, after dissolving, get water phase; Slowly add the water phase to the oil solution, stir until uniform and transparent, after the end of dropwise addition, continue to stir at 50℃ for 30 min, then keep warm at 75℃ for 30 min, get stabilized DHA nanoemulsion.

[0064] Example 3

[0065] Take 30 g fish oil, 0.5 g tea polyphenol and 0.3 g rosemary extract in 50℃ water bath for 10 min, get oil phase; In the oil phase, add 13 g polyglyceryl ricinoleate and 15 g Tween 60, mix in 50℃ water bath for 10 min, get oil solution; Take 10 g soybean polysaccharide, 1 g alanine, 0.2 g phytic acid and 30 mL deionized water in 50℃ water bath, after dissolving, get water phase; Slowly add the water phase to the oil solution, stir until uniform and transparent, after the end of dropwise addition, continue to stir at 50℃ for 30 min, then keep warm at 75℃ for 30 min, get stabilized DHA nanoemulsion.

[0066] Comparative Example 1

[0067] Take 30 g fish oil, 0.5 g tea polyphenol and 0.3 g rosemary extract in 50℃ water bath for 10 min, get oil phase; In the oil phase, add 13 g polyglyceryl ricinoleate and 15 g Tween 60, mix in 50℃ water bath for 10 min, get oil solution; Take 10 g soybean polysaccharide, 1 g alanine, 0.2 g phytic acid and 30 mL deionized water in 50℃ water bath, after dissolving, get water phase; Slowly add the water phase to the oil solution, stir until uniform and transparent, after the end of dropwise addition, continue to stir at 50℃ for 30 min, then keep warm at 75℃ for 30 min, get stabilized DHA nanoemulsion.

[0068] Comparative Example 2

[0069] Take 30 g fish oil, 0.5 g tea polyphenol and 0.3 g rosemary extract in 50℃ water bath for 10 min, get oil phase; In the oil phase, add 13 g polyglyceryl ricinoleate and 15 g Tween 60, mix in 50℃ water bath for 10 min, get oil solution; Take 10 g soybean polysaccharide, 1 g alanine, 0.2 g phytic acid and 30 mL deionized water in 50℃ water bath, after dissolving, get water phase; Slowly add the water phase to the oil solution, stir until uniform and transparent, after the end of dropwise addition, continue to stir at 50℃ for 30 min, then keep warm at 75℃ for 30 min, get stabilized DHA nanoemulsion.

[0070] Comparative Example 3

[0071] Take 30 g of fish oil, 0.5 g of glycyrrhiza extract and 0.3 g of gallic acid and mix for 10 min under a 50°C water bath to obtain an oil phase; add 28 g of sucrose ester to the oil phase and mix for 10 min under a 50°C water bath to obtain an oil solution; take 10 g of pullulan, 1 g of valine, 0.2 g of tannic acid and 30 mL of deionized water and mix under a 50°C water bath, and after dissolution, obtain an aqueous phase; slowly add the aqueous phase to the oil solution and stir until uniform and transparent, continue to stir at 50°C for 30 min after the end of the addition, and then incubate at 75°C for 30 min to obtain a DHA nanoemulsion.

[0072] Comparative Example 4

[0073] Take 30 g of fish oil and 0.3 g of vitamin E and mix for 10 min under a 50°C water bath to obtain an oil phase; add 7 g of citric acid fatty acid glycerol ester and 21 g of Tween 80 to the oil phase and mix for 10 min under a 50°C water bath to obtain an oil solution; take 10 g of trehalose and 31.7 mL of deionized water and mix under a 50°C water bath, and after dissolution, obtain an aqueous phase; slowly add the aqueous phase to the oil solution and stir until uniform and transparent, continue to stir at 50°C for 30 min after the end of the addition, and then incubate at 75°C for 30 min to obtain a DHA nanoemulsion.

[0074] Comparative Example 5

[0075] Take 30 g of fish oil and 0.3 g of TBHQ and mix for 10 min under a 50°C water bath to obtain an oil phase; add 7 g of citric acid fatty acid glycerol ester and 21 g of Tween 80 to the oil phase and mix for 10 min under a 50°C water bath to obtain an oil solution; take 10 g of trehalose and 31.7 mL of deionized water and mix under a 50°C water bath, and after dissolution, obtain an aqueous phase; slowly add the aqueous phase to the oil solution and stir until uniform and transparent, continue to stir at 50°C for 30 min after the end of the addition, and then incubate at 75°C for 30 min to obtain a DHA nanoemulsion.

[0076] Experimental Example 1: DHA content detection of the stabilized DHA nanoemulsion

[0077] The DHA content of the stabilized DHA nanoemulsion prepared in Examples 1-3 and the DHA nanoemulsion prepared in Comparative Examples 1-5 was detected according to “GB 5009.168-2016 Determination of fatty acids in food”, and the results are shown in Table 1.

[0078] The results show that there is no obvious difference in the DHA content of the stabilized DHA nanoemulsion prepared in Examples 1-3 and the DHA nanoemulsion prepared in Comparative Examples 1-5.

[0079] Experimental Example 2: Particle size determination of the stabilized DHA nanoemulsion

[0080] The particle size of the stabilized DHA nanoemulsion prepared in Examples 1-3 and the DHA nanoemulsion prepared in Comparative Examples 1-3 was determined using a Zetasizer Nano ZS nanoparticle size analyzer. The determination was performed after mixing the stabilized DHA nanoemulsion with hexane at a volume ratio of 5 μL: 1 mL and equilibrating for 4 min. The determination temperature was set to 20°C and the determination angle was set to 173°. The particle size determination results of the stabilized DHA nanoemulsion are shown in Table 1 and Figures 1-6 .

[0081] The results show that the stabilized DHA nanoemulsion prepared in Examples 1-3 is clear and transparent, and the emulsion particle size is below 100 nm. The DHA nanoemulsion prepared in Comparative Examples 1-3 is in a milkshake state, and the emulsion particle size is high, all above 200 nm.

[0082] Experimental Example 3: CDM value determination of the stabilized DHA nanoemulsion

[0083] The CDM value of the stabilized DHA nanoemulsion prepared in Examples 1-2 and the DHA nanoemulsion prepared in Comparative Examples 4-5 was determined using a Rancimat CDM tester. The determination conditions were as follows: the amount of the stabilized DHA nanoemulsion added was 3 g, the amount of water added was 70 mL, the amount of air blown was 20 L / h, and the determination temperature was 96°C. The CDM oxidation stability determination results of the stabilized DHA nanoemulsion are shown in Table 1 and Figures 7-10 .

[0084] The results show that the CDM value of the stabilized DHA nanoemulsion prepared in Examples 1-2 is high, and the antioxidant capacity is stronger. The CDM value of the DHA nanoemulsion prepared in Comparative Examples 4-5 is low, and the oxidation stability is poor.

[0085] Table 1: Physicochemical property detection results of the stabilized DHA nanoemulsion

[0086] Examples and comparative examples DHA content Particle size / nm CDM value / h Example 1 12.12 35.58 73.69 Example 2 12.15 42.94 68.11 Example 3 12.13 36.11 —— Comparative example 1 12.07 205.38 —— Comparative example 2 12.09 306.12 —— Comparative example 3 12.05 242.30 —— Comparative example 4 11.87 —— 2.06 Comparative example 5 11.96 —— 2.24

[0087] Experimental Example 4: Stability accelerated test of the stabilized DHA nanoemulsion

[0088] After the stabilized DHA nanoemulsion prepared in Examples 1-3 and the DHA nanoemulsion prepared in Comparative Examples 1-5 were placed at an environmental temperature of 37°C and an environmental humidity of 65% for 90 d, the DHA content of the stabilized DHA nanoemulsion was determined by the method of Experimental Example 1, the particle size of the stabilized DHA nanoemulsion was determined by the method of Experimental Example 2, and the CDM value of the stabilized DHA nanoemulsion was determined by the method of Experimental Example 3. The determination results are shown in Table 2.

[0089] The DHA content determination results of the stabilized DHA nanoemulsion show that after being placed at 37℃ for 90 days, the DHA content in the stabilized DHA nanoemulsion prepared in Examples 1-3 does not change significantly; while the DHA content in the DHA nanoemulsion prepared in Comparative Examples 1-5 decreases by 14.97%-38.42%, indicating that the DHA nanoemulsion has been severely oxidized.

[0090] The particle size determination results of the stabilized DHA nanoemulsion show that after being placed at 37℃ for 90 days, the stabilized DHA nanoemulsion prepared in Examples 1-3 is still clear and transparent, uniform and stable, and does not have the phenomena of stratification or precipitation, and the emulsion particle size does not change significantly; while the DHA nanoemulsion prepared in Comparative Examples 1-3 has serious stratification and precipitation phenomena and poor stability.

[0091] The CDM value determination results of the stabilized DHA nanoemulsion show that after being placed at 37℃ for 90 days, the CDM value in the stabilized DHA nanoemulsion prepared in Examples 1-2 does not change significantly, indicating that the stabilized DHA nanoemulsion prepared in Examples 1-2 has strong oxidation resistance; while the CDM value of the DHA nanoemulsion prepared in Comparative Examples 4-5 is extremely low, indicating that the DHA nanoemulsion prepared in Comparative Examples 4-5 has been severely deteriorated.

[0092] Table 2: Physical and chemical property detection results of the stabilized DHA nanoemulsion in the stability acceleration test

[0093] Examples and comparative examples DHA content Particle size / nm CDM value / h Example 1 12.01 40.94 68.49 Example 2 12.05 49.55 63.36 Example 3 12.00 41.32 —— Comparative example 1 10.26 361.87 —— Comparative example 2 10.28 556.21 —— Comparative example 3 10.23 444.72 —— Comparative example 4 7.31 —— 0.33 Comparative example 5 7.57 —— 0.51

[0094] It can be seen from the above examples that the present application provides a stabilized DHA nanoemulsion and a preparation method thereof. The stabilized DHA nanoemulsion prepared according to the method of the present application is clear and transparent, does not break emulsion, has good flavor, high bioavailability, is not easy to oxidize, can be stored for a long time at room temperature and high temperature environment, and has the advantages of strong emulsion stability, hydrophilicity and solubility.

[0095] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should also be considered as the protection scope of the present application.

Claims

1. A stabilized DHA nanoemulsion, characterized in that, It comprises the following components in parts by weight: 20-40 parts DHA oil, 5-20 parts oil-soluble emulsifier, 15-25 parts water-soluble emulsifier, 5-20 parts stabilizer, 0.5-2 parts antioxidant, 0.5-2 parts amino acids, 0.1-0.5 parts antioxidant synergist, and 10-30 parts deionized water; The amino acids include one or more of the following: lysine, glutamic acid, histidine, arginine, phenylalanine, alanine, leucine, isoleucine, methionine, proline, tryptophan, valine, cysteine, glycine, asparagine, serine, threonine, glutamine, tyrosine, and aspartic acid.

2. The stabilized DHA nanoemulsion according to claim 1, characterized in that, The DHA oil is algae oil and / or fish oil.

3. The stabilized DHA nanoemulsion according to claim 2, characterized in that, The oil-soluble emulsifier includes one or more of the following: lecithin, glyceryl citrate, diacetyl tartrate mono- and diglycerides, polyglycerol ricinoleate, sorbitan monostearate, sorbitan tristearate, sorbitan monooleate, sodium stearoyl lactylate, and calcium stearoyl lactylate.

4. The stabilized DHA nanoemulsion according to claim 3, characterized in that, The water-soluble emulsifier includes one or more of sucrose esters, polyglycerol fatty acid esters, sorbitan monolaurate, sorbitan monopalmitate, Tween 20, Tween 60, Tween 80, and caprylic / capric triglycerides.

5. The stabilized DHA nanoemulsion according to claim 4, characterized in that, The stabilizer includes one or more of trehalose, pullulan, lactose, fructooligosaccharides, glucose, soybean polysaccharides, cyclodextrin, sorbitol, maltitol, erythritol, xylitol, and mannitol.

6. The stabilized DHA nanoemulsion according to claim 5, characterized in that, The antioxidants include one or more of the following: γ-oryzanol, bamboo leaf antioxidants, tea polyphenols, licorice antioxidants, grape seed extract, rosemary extract, and gallic acid.

7. The stabilized DHA nanoemulsion according to claim 1, characterized in that, The antioxidant synergists include one or more of citric acid, EDTA, tartaric acid, phosphoric acid, tannic acid, malic acid, phytic acid, and ascorbic acid.

8. The stabilized DHA nanoemulsion according to claim 7, characterized in that, The stabilized DHA nanoemulsion has a particle size of <200nm.

9. The method for preparing the stabilized DHA nanoemulsion according to any one of claims 1 to 8, characterized in that, Includes the following steps: (1) Mix DHA oil and antioxidants to obtain the oil phase; (2) Mix the oil-soluble emulsifier, the water-soluble emulsifier and the oil phase to obtain an oil solution; (3) Mix the stabilizer, amino acid, antioxidant synergist and deionized water to obtain an aqueous phase; (4) After mixing the oil solution and the aqueous phase, stir and keep warm to obtain a stabilized DHA nano solution; The mixing temperature in steps (1) to (4) is 40 to 60°C. The mixing time in steps (1) to (2) is 5 to 15 minutes. The mixing time in step (4) is 20~40 min, the heat preservation temperature is 70~80℃, and the heat preservation time is 25~35 min.

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