Antioxidant vitamin A ester microcapsule and preparation method thereof

Abstract

The invention discloses an antioxidant vitamin A ester microcapsule and a preparation method thereof, vitamin A ester is prepared into compact solid powder, external oxygen is effectively isolated, the solid powder is used as a core material, one or two of hydrogenated oil or monoglyceride is / are mixed with phospholipid as a wall material, and the antioxidant vitamin A ester microcapsule is prepared. The core material and the wall material are mixed and then subjected to high-speed dispersion and spray condensation treatment to obtain the vitamin A ester microcapsule, so that the storage stability of the vitamin A ester is greatly improved; meanwhile, the preparation process is simple, and large-scale production is facilitated. The encapsulation efficiency of the antioxidant vitamin A ester microcapsule prepared by the method is more than 90%. And in 35-day accelerated storage test evaluation at 37 DEG C, the retention rate is 80% or above and is obviously higher than the retention rate of the raw materials.

Description

Technical Field

[0001] The invention belongs to the technical field of vitamin A microcapsule preparation, and specifically relates to an antioxidant vitamin A ester microcapsule and a preparation method thereof. Background Art

[0002] Vitamin A is a fat-soluble vitamin that has the function of maintaining normal visual function, cell growth and differentiation. Vitamin A is also related to the body's nonspecific immune function and specific immune function. It has a polyene structure and is therefore very sensitive to oxidation, especially on -OH and polyene groups. Vitamin A esters are more stable than vitamin A because the -OH is blocked, but are still sensitive to ultraviolet light, oxygen and other conditions. During the photoreaction of vitamin A, oxygen can accelerate the photocatalytic degradation of vitamin A, and the degradation rate in the presence of oxygen is twice that in the absence of oxygen. The traditional encapsulation method is to prepare vitamin A into an emulsion and then spray-dry it, which cannot completely isolate the influence of oxygen. Summary of the invention

[0003] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0004] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0005] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing antioxidant vitamin A ester microcapsules.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: comprising:

[0007] Gum Arabic and glucose syrup are dissolved in water and dispersed at high speed to form an aqueous phase;

[0008] The melted vitamin A ester is mixed with soybean oil as oil phase I;

[0009] The aqueous phase is mixed with the oil phase I to obtain an emulsion, an antioxidant is added thereto, and a uniform emulsion is obtained by high-speed shearing and high-pressure homogenization;

[0010] The uniform emulsion is spray-dried to obtain vitamin A ester powder;

[0011] One or both of hydrogenated oil or monoglyceride and phospholipid are heated in a water bath until melted, and then dispersed at high speed to obtain a uniform oil phase II;

[0012] Vitamin A ester powder and oil phase II are mixed in a mass ratio of 1:0.5-4 and dispersed at high speed until uniform to obtain a suspension;

[0013] The suspension is subjected to spray condensation treatment to obtain vitamin A ester microcapsules.

[0014] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the mass ratio of gum arabic to glucose syrup is 1 to 5:1, and the dissolution temperature is 60°C.

[0015] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the mass ratio of the total mass of gum arabic and glucose syrup to water in the aqueous phase is 1:4-8.

[0016] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the high-speed dispersion can be carried out by conventional dispersion methods in the art, such as magnetic stirring and a stirrer, so as to achieve the effect of uniformly dispersing gum arabic and glucose syrup in water.

[0017] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the vitamin A ester includes vitamin A acetate and vitamin A palmitate, the antioxidant includes ascorbic acid or sodium ascorbate, the hydrogenated oil includes one of hydrogenated palm oil and extremely hydrogenated high-erucic acid rapeseed oil, and the monoglyceride includes one of monobehenic acid glyceryl, monopalmitic acid glyceryl, monolauric acid glyceryl and monostearic acid glyceryl.

[0018] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the mass ratio of the vitamin A ester to soybean oil is 5:1-5.

[0019] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the mass ratio of the oil phase I to the water phase is 1:2-4.

[0020] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the mass ratio of the antioxidant to the total solids of the emulsion is 1 to 5:100.

[0021] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the oil phase I is mixed with the water phase and high-speed sheared at 10000 rpm for 2 min.

[0022] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the mass ratio of the monoglyceride to the hydrogenated oil is 1:1-5.

[0023] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the amount of the phospholipid is 0-1% of the oil phase II.

[0024] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the high-pressure homogenization pressure of the emulsion is 30 to 50 MPa, and the number of cycles is 2 to 3 times.

[0025] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the air inlet temperature of the spray drying is 100-170°C.

[0026] As a preferred embodiment of the method for preparing the antioxidant vitamin A ester microcapsules of the present invention, the feed rate of the spray condensation is 18-26 ml / min, and the insulation temperature of the circulating water in the spray head is 75-80°C.

[0027] Another object of the present invention is to provide a method for preparing antioxidant vitamin A ester microcapsules.

[0028] Beneficial effects of the present invention:

[0029] The present invention prepares vitamin A ester into a dense solid preparation by means of microcapsules, effectively isolates it from damage by external oxygen, light, etc., and greatly improves the storage stability of vitamin A ester; at the same time, the preparation process involved in the present invention is simple and convenient for scaled-up production. The antioxidant vitamin A ester microcapsules prepared by the method have an encapsulation rate of more than 90%. In the evaluation of the 37°C accelerated 35d storage test, the retention rate is more than 80%, which is significantly higher than the retention rate of the raw material. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0031] Figure 1 It is the melting point of the mixed oil phase of extremely hydrogenated high erucic acid rapeseed oil and glyceryl monobehenate = 1:1 determined by DSC.

[0032] Figure 2 is the melting point of hydrogenated palm oil determined by DSC.

[0033] Figure 3 This is the melting point of extremely hydrogenated high erucic acid rapeseed oil determined by DSC. DETAILED DESCRIPTION

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0035] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0036] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0037] Unless otherwise specified, the raw materials used in the present invention are all commercially available in the art, among which the extremely hydrogenated high-erucic acid rapeseed oil was purchased from Yihai Kerry (Nanhai Oils & Fats Industry (Chiwan) Co., Ltd.).

[0038] The vitamin A acetate loading determination method of the present invention is:

[0039] 1. Preparation of Vitamin A standard curve:

[0040] Vitamin A standard solutions (1.8, 4.6, 6.8, 9.2, 18.4 IU / mL) were tested by high performance liquid chromatography to prepare a standard curve.

[0041] 2. Sample solution preparation:

[0042] (1) Saponification

[0043] Weigh 1g (accurate to 0.001g) (about 0.1gVA) of sample into a 250mL round-bottom flask, add a few grains of BHT and 50mL L-ascorbic acid ethanol solution to completely disperse and soak the sample, add 20mL potassium hydroxide solution and mix well. Place in a boiling water bath (90℃) and reflux for 35min, shaking from time to time to prevent the sample from adhering to the wall of the flask. After saponification is completed, rinse the inside of the condenser with 5mL-10mL water from the top of the condenser, take out the flask and cool it to about 40℃.

[0044] (2) Extraction

[0045] Transfer all the saponified liquid to a 500mL separatory funnel containing 100mL petroleum ether, rinse the round-bottom flask with 35mL water × 3 times, and pour it into the separatory funnel, cover, vent, then mix, shake vigorously for 2 minutes, let stand, and separate. Transfer the aqueous phase to the second separatory funnel, extract it twice with 60mL and 60mL petroleum ether in batches, discard the aqueous phase, and combine the three petroleum ether phases.

[0046] (3) Washing

[0047] Wash the ether layer with about 100 mL of water, repeat 4 times until the ether layer is neutral, and remove the lower aqueous phase. Gently swirl during the first water wash to prevent emulsification.

[0048] (4) Concentration

[0049] The ether layer extract after washing was collected into a 250 mL volumetric flask, fixed to volume and allowed to stand, 5 mL to 10 mL volumetric flask was taken, dried with nitrogen, dissolved in methanol, fixed to volume, injected, and chromatographically determined.

[0050] 3. Chromatographic conditions

[0051] a) Chromatographic column: C18 column (250mm×4.6mm×5μm)

[0052] b) Column temperature: 35°C

[0053] c) Mobile phase: methanol: water = 95:5

[0054] d) Flow rate: 1.0 mL / min

[0055] e) UV detection wavelength: 325nm

[0056] f) Injection volume: 20 μL

[0057] g) Injection time: 10min

[0058] 4. Analysis results and calculations

[0059] The content of vitamin A in the sample was calculated according to formula (1):

[0060]

[0061] Where:

[0062] X——the content of vitamin A in the sample, in IU / g;

[0063] ——The concentration of vitamin A in the sample calculated according to the standard curve, in IU / mL;

[0064] V——the final volume of the sample solution, in mL;

[0065] m——sample sampling volume, unit: g or mL.

[0066] The sample retention rate test method is: pack in aluminum foil bags, 2 g per bag, and accelerate in a 37°C oven for 35 days.

[0067] Example 1

[0068] This embodiment provides a method for preparing antioxidant vitamin A ester microcapsules, specifically:

[0069] 1) Preparation of aqueous phase:

[0070] 15 g of gum arabic and 7.5 g of glucose syrup were dissolved in 170 g of warm water at 60° C. and dispersed at high speed to form an aqueous phase, wherein the mass ratio of gum arabic to glucose syrup was 2:1.

[0071] 2) Oil phase preparation:

[0072] 6.25 g of melted vitamin A acetate was mixed with 1.25 g of soybean oil as oil phase I, where the mass ratio of vitamin A acetate to soybean oil was 5:1;

[0073] 3) Emulsion preparation:

[0074] The aqueous phase and the oil phase I were mixed to obtain an emulsion, 0.15 g of ascorbic acid was added, high-speed shearing was performed for 2 min at a shear rate of 10,000 rpm, and high-pressure homogenization was performed at 40 MPa for 3 times to obtain a uniform emulsion.

[0075] 4) Spray drying:

[0076] The uniform emulsion was passed into a spray drying device with an inlet air temperature of 170° C. and spray-dried to obtain vitamin A ester powder.

[0077] 5) Preparation of suspension:

[0078] Extremely hydrogenated high-erucic acid rapeseed oil and monobehenic acid glyceride are mixed with phospholipids in a mass ratio of 1:1, heated in a water bath until melted, and dispersed at high speed until the oil phase is uniform to obtain oil phase II, wherein the amount of phospholipids is 1% of oil phase II, and vitamin A acetate powder obtained by spray drying is added, the powder: oil phase II = 1:1, and dispersed at high speed until uniform to obtain a suspension.

[0079] 6) Spray condensation:

[0080] The suspension was fed at 22 ml / min and collected by spray condensation device to obtain the vitamin A ester microcapsules of this embodiment, wherein the insulation temperature of the circulating water in the spray head was 75°C.

[0081] Example 2

[0082] The difference between this embodiment and embodiment 1 is that the suspension preparation in step 5) is adjusted:

[0083] 5) Preparation of suspension:

[0084] The hydrogenated palm oil and lecithin are mixed and heated in a water bath until they are melted, and dispersed at high speed until the oil phase is uniform to obtain oil phase II, wherein the amount of lecithin is 1% of oil phase II, and spray-dried vitamin A ester powder is added, the powder: oil phase II = 1:1, and dispersed at high speed until uniform to obtain a suspension.

[0085] The remaining steps and processes are all referred to Example 1 to obtain the vitamin A ester microcapsules of this example.

[0086] Example 3

[0087] The difference between this embodiment and embodiment 1 is that the suspension preparation in step 5) is adjusted:

[0088] 5) Preparation of suspension:

[0089] The extremely hydrogenated high-erucic acid rapeseed oil and lecithin are mixed and heated in a water bath until melted, and dispersed at high speed until the oil phase is uniform to obtain oil phase II, wherein the amount of lecithin is 1% of oil phase II, and spray-dried vitamin A ester powder is added, the powder: oil phase II = 1:1, and dispersed at high speed until uniform to obtain a suspension.

[0090] The remaining steps and processes are all referred to Example 1 to obtain the vitamin A ester microcapsules of this example.

[0091] Comparative Example 1

[0092] The difference between this comparative example and Example 1 is that ascorbic acid in step 3) emulsion preparation and phospholipid in step 5) suspension preparation are omitted, and the remaining steps and processes are referred to Example 1 to obtain the vitamin A acetate microcapsules of this comparative example.

[0093] The loading, encapsulation efficiency and retention rate of the vitamin A ester microcapsules obtained in Examples 1 to 3 and Comparative Example 1 are shown in Table 1 and Figures 1 to 3 shown.

[0094] Table 1

[0095] Sample name Loading capacity (wIU / g) Encapsulation rate (%) Retention rate (%) Example 1 14.37 97.41 81.18 Example 2 12.82 90.03 68.74 Example 3 13.92 97.78 75.66 Comparative Example 1 8.63 83.19 67.42

[0096] It can be seen from Table 1 that the encapsulation rate and retention rate of different spray condensation wall materials (oil phase II) are significantly different. Different oil phase components have different physical and chemical properties, which will affect the fluidity, viscosity and curing speed of the wall material, thereby affecting the encapsulation effect.

[0097] The extremely hydrogenated high-erucic acid rapeseed oil has a higher degree of saturation, which reduces the number of unsaturated bonds and thus reduces the sensitivity to oxidation. This highly saturated oil phase can better protect vitamin A esters from oxidative damage. Monobehenic acid glyceryl is a long-chain fatty acid monoglyceride with good emulsification, stability and biocompatibility. They can work synergistically with other ingredients such as phospholipids to form a more stable oil phase system, which is conducive to the encapsulation and storage of vitamin A esters.

[0098] Figure 1 to Figure 3 The DSC measurement results of different oils in the oil phase II used in Examples 1 to 3 are shown in order. The results show that the melting point of extremely hydrogenated high-erucic acid rapeseed oil + monobehenic acid glyceryl is closest to the insulation temperature during the spray condensation process, which means that during the spray condensation stage, the oil phase II can be quickly and evenly solidified to form a dense microcapsule wall material, effectively encapsulating the vitamin A ester. This good matching helps to reduce the loss during the microcapsule preparation process and improve the encapsulation rate.

[0099] Example 4

[0100] This example is used to explore the effect of different suspension feed rates on the performance of the obtained capsules. The difference from Example 1 is that the feed rates of spray condensation in step 6) are adjusted to 18, 20, 22, 24, and 26 mL / min, respectively. The remaining steps and processes are all referred to Example 2. Vitamin A ester microcapsules prepared at different feed rates in this example are obtained, and their relevant properties are tested. The results are shown in Table 2.

[0101] Table 2

[0102] Feed rate mL / min Loading capacity (wIU / g) Encapsulation rate (%) 18 14.68 95.88 20 14.96 97.14 22 14.37 97.41 24 14.08 97.93 26 15.09 99.06

[0103] It can be seen from Table 2 that different spray condensation feed rates have a certain effect on the encapsulation rate. The faster the feed rate, the higher the encapsulation rate. As the feed rate increases, the droplets formed during the spray condensation process may be finer. The finer droplets have a larger surface area during the drying process, which is conducive to the rapid evaporation of water, thereby accelerating the condensation process, which helps to form a tighter capsule wall structure and improve the encapsulation rate. Within the scope of the present invention, better encapsulation effects can be achieved.

[0104] Example 5

[0105] This example is used to explore the effect of different phospholipid dosages on the performance of the prepared capsules. The difference from Example 2 is that the phospholipid dosage in step 5) is adjusted to 0.3, 0.5, 0.8, 1%, and 1.5%, respectively. The remaining steps and processes are all referred to Example 2. Vitamin A ester microcapsules prepared at different feed rates in this example are obtained, and their relevant properties are tested. The results are shown in Table 3.

[0106] Table 3

[0107] Phospholipid addition amount / % Loading capacity (wIU / g) Encapsulation rate (%) 0.3 10.59 95.56 0.5 11.38 95.37 0.8 11.37 96.35 1 14.37 97.41 1.5 12.74 92.65

[0108] It can be seen from Table 3 that different amounts of phospholipid addition have a certain effect on the loading capacity and encapsulation efficiency of the prepared microcapsules. This is because phospholipids, as natural amphiphilic molecules, can form a stable interface film between the oil phase and the aqueous phase, and enhance the structural strength of the microcapsules. Adding phospholipids to the oil phase II not only improves the emulsification stability and dispersibility of the oil phase, but also helps to form more uniform microcapsule particles, thereby affecting the encapsulation efficiency and retention rate. Too high a phospholipid content may lead to poor emulsification effect and uneven distribution of emulsion droplets, thereby affecting the subsequent encapsulation effect and the loading capacity of vitamin A. Good results can be achieved within the scope of the present invention.

[0109] Example 6

[0110] This example is used to explore the effect of the ratio of different powders and oil phases in the suspension on the performance of the obtained capsules. The difference from Example 2 is that the ratio of powder: oil phase II in step 5) is adjusted to 2:3, 1:1, and 3:2, respectively. The remaining steps and processes are all based on Example 2. Vitamin A ester microcapsules prepared with different powders and oil phases in this example are obtained, and their relevant properties are tested. The results are shown in Table 4.

[0111] Table 4

[0112] Powder: Oil Phase II Loading capacity (wIU / g) Encapsulation rate (%) 2:3 13.10 97.98 1:1 14.37 97.41 3:2 21.56 92.91

[0113] It can be seen from Table 4 that the ratio of vitamin A ester powder and oil phase II is one of the key factors affecting the vitamin A loading and encapsulation rate of the prepared capsules. An appropriate ratio can ensure that the wall material can fully wrap the core material to form a stable microcapsule structure. Good technical effects can be achieved within the ratio range of the present invention.

[0114] Example 7

[0115] This example is used to explore the effect of the inlet air temperature in the spray drying step on the performance of the obtained capsules. The difference from Example 2 is that the inlet air temperature in step 4) is adjusted to 120°C, 150°C, and 170°C, respectively. The remaining steps are all based on Example 2. Vitamin A ester microcapsules prepared at different inlet air temperatures in this example are obtained, and their relevant properties are tested. The results are shown in Table 5.

[0116] Table 5

[0117] Inlet air temperature Loading capacity (mg / g) Encapsulation rate (%) 120℃ 17.60 95.64 150℃ 16.82 96.31 170℃ 14.37 97.41

[0118] As can be seen from Table 5, the inlet air temperature has a significant effect on the performance of the prepared capsules. As an important parameter in the spray drying process, the inlet air temperature not only affects the drying speed and degree of the material, but is also directly related to the quality and stability of the product. As the inlet air temperature increases, the fluidity of the wall material may increase, making it easier for the wall material to form a uniform coating around the core material, which helps to reduce the exposure of the core material and thus improve the encapsulation rate. However, at the same time, a higher inlet air temperature may cause some vitamin A to volatilize or degrade due to heat, thereby reducing its content in the microcapsule, that is, the loading capacity decreases. Therefore, it is necessary to balance the relationship between the two.

[0119] In summary, the present invention prepares vitamin A ester into a dense solid preparation by means of microcapsules, effectively isolates it from damage by external oxygen, light, etc., and greatly improves the storage stability of vitamin A ester; at the same time, the preparation process involved in the present invention is simple and easy to scale up production. The antioxidant vitamin A ester microcapsules prepared by this method have an encapsulation rate of more than 90%. In the evaluation of the 37°C accelerated 35d storage test, the retention rate is more than 80%, which is significantly higher than the retention rate of the raw material.

[0120] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing antioxidant vitamin A ester microcapsules, characterized in that: include, Gum Arabic and glucose syrup are dissolved in water and dispersed at high speed to form an aqueous phase; The melted vitamin A ester is mixed with soybean oil as oil phase I; The aqueous phase is mixed with the oil phase I to obtain an emulsion, an antioxidant is added thereto, and a uniform emulsion is obtained by high-speed shearing and high-pressure homogenization; The uniform emulsion is spray-dried to obtain vitamin A ester powder; One or both of hydrogenated oil or monoglyceride and phospholipid are heated in a water bath until melted, and then dispersed at high speed to obtain a uniform oil phase II; Vitamin A ester powder and oil phase II are mixed in a mass ratio of 1:0.5-4 and dispersed at high speed until uniform to obtain a suspension; The suspension is subjected to spray condensation treatment to obtain vitamin A ester microcapsules.

2. The method for preparing the antioxidant vitamin A ester microcapsules according to claim 1, characterized in that: The mass ratio of the gum arabic to the glucose syrup is 1-5:1, and the dissolution temperature is 60°C.

3. The method for preparing the antioxidant vitamin A ester microcapsules according to claim 1, characterized in that: In the aqueous phase, the mass ratio of the total mass of gum arabic and glucose syrup to water is 1:4-8.

4. The method for preparing the antioxidant vitamin A ester microcapsules according to claim 1, characterized in that: The vitamin A ester includes vitamin A acetate and vitamin A palmitate, the antioxidant includes ascorbic acid or sodium ascorbate, the hydrogenated oil includes one of hydrogenated palm oil and extremely hydrogenated high-erucic acid rapeseed oil, and the monoglyceride includes one of monobehenic acid glyceryl, monopalmitic acid glyceryl, monolauric acid glyceryl and monostearic acid glyceryl.

5. The method for preparing the antioxidant vitamin A ester microcapsules according to claim 2, characterized in that: The mass ratio of the vitamin A ester to soybean oil is 5:1-5.

6. The method for preparing the antioxidant vitamin A ester microcapsules according to claim 1, characterized in that: The amount of the phospholipid is 0-1% of the oil phase II.

7. The method for preparing antioxidant vitamin A ester microcapsules according to claim 1, characterized in that: The high-pressure homogenization pressure of the emulsion is 30-50 MPa, and the number of cycles is 2-3 times.

8. The method for preparing antioxidant vitamin A ester microcapsules according to claim 1, characterized in that: The inlet air temperature of the spray drying is 100-170°C.

9. The method for preparing antioxidant vitamin A ester microcapsules according to claim 1, characterized in that: The feed rate of the spray condensation is 18-26 ml / min, and the insulation temperature of the circulating water in the spray head is 75-80°C.

10. Antioxidant vitamin A ester microcapsules prepared by the preparation method according to any one of claims 1 to 9.

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