High-antioxidant grape seed essential oil microcapsule as well as preparation method and application thereof

Abstract

The invention provides a high-antioxidant grape seed essential oil microcapsule as well as a preparation method and application thereof, and belongs to the technical field of microcapsule preparation. The preparation method comprises the following steps: taking hydroxypropyl-beta-cyclodextrin as a wall material, mixing grape seed essential oil with a wall material solution, homogenizing, standing at low temperature, freeze-drying, crushing and sieving to obtain the microcapsule. By optimizing the core-wall ratio (1: 6-8), the embedding temperature (30-50 DEG C) and the embedding time (40-60 minutes), the embedding rate, the total phenol content and the flavonoid content of the microcapsule are improved, and the antioxidant activity is remarkably improved. The DPPH free radical scavenging rate, the hydroxyl free radical scavenging rate and other indexes of the microcapsule are improved by 10% or above compared with those of a traditional beta-cyclodextrin system, and the stability is improved. The grape seed essential oil microcapsule solves the problems of low embedding rate and easy degradation of active components of the grape seed essential oil microcapsule, and is suitable for the fields of functional foods, cosmetics and medicines.

Description

Technical Field

[0001] The invention belongs to the technical field of microcapsule preparation, and in particular relates to a high-antioxidant grape seed essential oil microcapsule, a preparation method and an application thereof. Background Art

[0002] Grape seed essential oil, a natural oil extracted from grape seeds, is rich in polyphenolic compounds, particularly proanthocyanidins, which exhibit significant antioxidant, anti-inflammatory, and anti-aging activities. However, the active ingredients in grape seed essential oil are susceptible to degradation by factors such as light, heat, and oxygen, resulting in reduced stability and bioavailability. To overcome this problem, microencapsulation technology is widely used to protect the active ingredients, improving their stability and sustained-release properties.

[0003] Traditional microencapsulation technology typically uses β-cyclodextrin as a wall material, but its encapsulation efficiency is low and its protection of active ingredients is limited. In recent years, hydroxypropyl-β-cyclodextrin, as a new wall material, has gradually attracted attention due to its improved water solubility and encapsulation capacity. However, research on the application of hydroxypropyl-β-cyclodextrin in grape seed essential oil microencapsulation is relatively limited, and existing technologies still have problems such as low encapsulation efficiency and easy degradation of active ingredients. Summary of the Invention

[0004] In view of this, the object of the present invention is to provide a high antioxidant grape seed essential oil microcapsule and its preparation method and application, which improves the embedding rate, has a high content of active ingredients, and has stronger antioxidant properties and stability.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] A method for preparing high-antioxidant grape seed essential oil microcapsules comprises the following steps:

[0007] A hydroxypropyl-β-cyclodextrin aqueous solution is used as the wall material solution, and a mixture of grape seed essential oil and ethanol is used as the core material; the core material is added to the wall material solution for embedding, and dispersed and homogenized to form an emulsion; the emulsion is allowed to stand, filtered, and freeze-dried to produce grape seed essential oil microcapsules;

[0008] The mass ratio of the embedded core to the wall is 1:6-8, the time is 40-60 minutes, and the temperature is 30-50°C.

[0009] Preferably, the wall material solution is prepared by mixing hydroxypropyl-β-cyclodextrin and water at a ratio of 1 g:1.5-2 mL at 55-65°C.

[0010] Preferably, the core material is a mixture of grape seed essential oil and ethanol at 30-40° C. in an equal volume ratio; the concentration of the ethanol is 90-100 wt %.

[0011] Preferably, the speed of the dispersion and homogenization is 1000-2000 rpm, the time is 20-30 min, and the temperature is 35-45°C.

[0012] Preferably, the standing temperature is 4-5° C. and the standing time is 8-12 hours.

[0013] Preferably, the filtration is followed by washing with anhydrous ethanol for 3 to 4 times.

[0014] Preferably, the freeze-drying temperature is -60 to -40°C, the air pressure is less than 10 Pa, and the time is 24 to 48 hours.

[0015] Preferably, the method further comprises sieving and crushing the grape seed essential oil microcapsules to a particle size of ≤80 mesh after freeze-drying.

[0016] The present invention also provides high-antioxidant grape seed essential oil microcapsules prepared by the preparation method and applications of the microcapsules in preparing foods, cosmetics or medicines.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The present invention uses hydroxypropyl-β-cyclodextrin as a wall material, significantly improving the stability of grape seed essential oil microcapsules, extending the shelf life of the active ingredient, and reducing degradation of the active ingredient by factors such as light, heat, and oxygen. Furthermore, by optimizing the core-to-wall ratio (1:6-8), embedding temperature (30-50°C), and embedding time (40-60 minutes), the embedding efficiency and antioxidant activity of grape seed essential oil were significantly increased, with DPPH and hydroxyl radical scavenging rates exceeding 10% compared to traditional β-cyclodextrin systems.

[0019] The grape essential oil microcapsules prepared by the present invention are suitable for the fields of functional foods, cosmetics and medicines, can effectively protect the active ingredients of the grape seed essential oil, and improve its bioavailability and application effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The effect of core-to-wall ratio on the encapsulation efficiency of grape seed essential oil;

[0021] Figure 2 The effect of embedding time on the embedding efficiency of grape seed essential oil;

[0022] Figure 3 The effect of embedding temperature on the embedding efficiency of grape seed essential oil;

[0023] Figure 4 The superoxide anion free radical scavenging ability of different grape seed essential oil microcapsules;

[0024] Figure 5 The hydroxyl radical scavenging ability of different grape seed essential oil microcapsules;

[0025] Figure 6 The standard curve of Trolox's DPPH scavenging ability and the DPPH free radical scavenging ability of different grape seed essential oils;

[0026] Figure 7 The standard curve of total phenols and the total phenol content of different grape seed essential oil microcapsules;

[0027] Figure 8 The standard curve of total flavonoids and the total flavonoid content of different grape seed microcapsules;

[0028] Figure 9 The effect of time on the peroxide value of different grape seed essential oil microcapsules;

[0029] Figure 10 The effect of light on the retention rate of different grape seed microcapsules. DETAILED DESCRIPTION

[0030] The present invention provides a method for preparing high-antioxidant grape seed essential oil microcapsules, comprising the following steps:

[0031] (1) Prepare wall material solution:

[0032] The present invention uses a hydroxypropyl-β-cyclodextrin aqueous solution as the wall material solution. Preferably, the wall material solution is prepared by mixing hydroxypropyl-β-cyclodextrin and water at a ratio of 1g:1.5-2mL at 55-65°C; more preferably, hydroxypropyl-β-cyclodextrin and water are mixed at a ratio of 1g:1.75mL and dissolved at 60°C to prepare a saturated solution. As an embodiment, 20g of hydroxypropyl-β-cyclodextrin is weighed into a beaker, 35mL of water is added, and the mixture is heated to 60°C and dissolved under mild heat to obtain a saturated wall material solution.

[0033] (2) Preparation of oil phase core material:

[0034] The present invention uses a mixture of grape seed essential oil and ethanol as the oil phase core material. Preferably, the core material is a mixture of grape seed essential oil and ethanol in equal volume ratios at 30-40°C, more preferably 35°C. The concentration of ethanol is preferably 90-100% by weight, and more preferably anhydrous ethanol.

[0035] (3) Embedding:

[0036] The core material is added to the wall material solution for embedding, and dispersed and homogenized to form an emulsion. In the embedding process of the present invention, the core-wall mass ratio is 1:6-8, preferably 1:7; the stirring time is 40-60 minutes, preferably 50°C; the embedding temperature is 30-50°C, preferably 40°C; more preferably, the core material is added while stirring the wall material solution for embedding. Preferably, the speed of dispersion and homogenization is 1000-2000 rpm, more preferably 1500 rpm; the time is 20-30 minutes, more preferably 25 minutes; the temperature is 35-45°C, more preferably 40°C. As an embodiment, the dispersion and homogenization is carried out by magnetic stirring.

[0037] (4) Standing, filtering, and drying:

[0038] The emulsion is allowed to stand, filtered, and then freeze-dried to produce grape seed essential oil microcapsules. The stand temperature is preferably 4-5°C for 8-12 hours. After filtration, the emulsion is preferably washed 3-4 times with anhydrous ethanol. The freeze-drying temperature is preferably -60-40°C, more preferably -50°C, with an air pressure of <10 Pa, and the drying time is 24-48 hours, preferably 36 hours. Precooling at -80°C for 24 hours before freeze-drying is more preferred.

[0039] (5) Crushing and screening:

[0040] The freeze-dried grape seed essential oil microcapsules are crushed and sieved. Preferably, the grape seed essential oil microcapsules have a particle size of ≤80 mesh. As an embodiment, the freeze-dried grape seed essential oil microcapsules are crushed, ground, and sieved through an 80-mesh sieve.

[0041] The present invention also provides high-antioxidant grape seed essential oil microcapsules prepared by the preparation method and applications of the microcapsules in preparing foods, cosmetics or medicines.

[0042] The technical solutions provided by the present invention are described in detail below with reference to the embodiments, but they should not be construed as limiting the scope of protection of the present invention.

[0043] Example 1

[0044] A high antioxidant grape seed essential oil microcapsule, the preparation method is as follows:

[0045] (1) Preparation of wall material solution: Weigh 20 g of hydroxypropyl-β-cyclodextrin into a beaker, add 35 mL of water, and heat to 60°C to dissolve to prepare a saturated wall material solution.

[0046] (2) Preparation of oil phase core material: Mix grape seed essential oil and anhydrous ethanol in a volume ratio of 1:1 and heat to 35°C.

[0047] (3) Encapsulation: Slowly add the oil phase into the wall material solution while stirring, control the core-wall mass ratio to be 1:7, the stirring time to be 50 min, and the encapsulation temperature to be 40°C.

[0048] (4) Dispersion and homogenization: Homogenize the mixture at 40°C and 1500 rpm for 25 min to form an emulsion.

[0049] (5) Standing: Let the emulsion stand at 4°C for 10 h.

[0050] (6) Filtration: The emulsion was filtered after standing and washed with anhydrous ethanol three times.

[0051] (7) Freeze drying: The filtered sample was precooled at -80 °C for 24 h and freeze dried at -50 °C and air pressure <10 Pa for 36 h.

[0052] (8) Crushing and screening: The dried microcapsules are crushed and ground, and passed through an 80-mesh sieve to obtain high antioxidant grape seed essential oil microcapsules.

[0053] Example 2

[0054] A high antioxidant grape seed essential oil microcapsule, the preparation method is as follows:

[0055] (1) Preparation of wall material solution: Weigh 20 g of hydroxypropyl-β-cyclodextrin into a beaker, add 35 mL of water, and heat to 60°C to dissolve to prepare a saturated wall material solution.

[0056] (2) Preparation of oil phase core material: Mix grape seed essential oil and anhydrous ethanol in a volume ratio of 1:1 and heat to 30°C.

[0057] (3) Encapsulation: Slowly add the oil phase into the wall material solution while stirring, control the core-wall mass ratio to be 1:6, the stirring time to be 40 min, and the encapsulation temperature to be 30°C.

[0058] (4) Dispersion and homogenization: Homogenize the mixture at 35°C and 1000 rpm for 30 min to form an emulsion.

[0059] (5) Standing: Let the emulsion stand at 4°C for 8 h.

[0060] (6) Filtration: The emulsion was filtered after standing and washed with ethanol three times.

[0061] (7) Freeze drying: The filtered sample was precooled at -80°C for 24 h, and freeze dried at -60°C and air pressure <10 Pa for 24 h.

[0062] (8) Crushing and screening: The dried microcapsules are crushed and ground, and passed through a 100-mesh sieve to obtain high antioxidant grape seed essential oil microcapsules.

[0063] Example 3

[0064] A high antioxidant grape seed essential oil microcapsule, the preparation method is as follows:

[0065] (1) Preparation of wall material solution: Weigh 20 g of hydroxypropyl-β-cyclodextrin into a beaker, add 35 mL of water, and heat to 60°C to dissolve to prepare a saturated wall material solution.

[0066] (2) Preparation of oil phase core material: Mix grape seed essential oil and anhydrous ethanol in a volume ratio of 1:1 and heat to 40°C.

[0067] (3) Encapsulation: Slowly add the oil phase into the wall material solution while stirring, control the core-wall mass ratio to be 1:8, the stirring time to be 60 min, and the encapsulation temperature to be 50 °C.

[0068] (4) Dispersion and homogenization: Homogenize the mixture at 45°C and 2000 rpm for 20 min to form an emulsion.

[0069] (5) Standing: Let the emulsion stand at 5°C for 12 hours.

[0070] (6) Filtration: The emulsion was filtered after standing and washed with ethanol 4 times.

[0071] (7) Freeze drying: The filtered sample was precooled at -80°C for 24 h, and freeze dried at -40°C and air pressure <10 Pa for 48 h.

[0072] (8) Crushing and screening: The dried microcapsules are crushed and ground, and passed through an 80-mesh sieve to obtain high antioxidant grape seed essential oil microcapsules.

[0073] Test Example 1

[0074] Effects of different preparation conditions on the embedding efficiency of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules

[0075] A single-factor experiment was conducted to determine the encapsulation efficiency of hydroxypropyl-β-cyclodextrin grape seed oil microcapsules using the saturated solution method. The encapsulation was performed at core-to-wall mass ratios (hydroxypropyl-β-cyclodextrin:grape seed oil) of 1:5, 1:6, 1:7, and 1:8; at temperatures of 20°C, 30°C, 40°C, 50°C, and 60°C; and at stirring times of 30 min, 40 min, 50 min, and 60 min.

[0076] pass Figures 1 to 3As can be seen, at a core-to-wall ratio of 1:7, the embedding efficiency of β-cyclodextrin and hydroxypropyl-β-cyclodextrin reached its maximum, reaching 82.1% and 85.5%, respectively. At a stirring time of 40 minutes, the embedding efficiency of β-cyclodextrin reached a maximum of 82.7%, while that of hydroxypropyl-β-cyclodextrin reached a maximum of 84.5% at 50 minutes. At a temperature of 40°C, the embedding efficiency of β-cyclodextrin and hydroxypropyl-β-cyclodextrin reached its maximum, reaching 81.8% and 84.9%, respectively. Overall, hydroxypropyl-β-cyclodextrin as a wall material exhibited a higher embedding efficiency than β-cyclodextrin.

[0077] Test Example 2

[0078] Differences in properties of grape seed essential oil microcapsules with different wall materials

[0079] Comparative Example 1: The difference from Example 1 is that the wall material solution is β-cyclodextrin.

[0080] The hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules prepared in Example 1 and the β-cyclodextrin grape seed essential oil microcapsules prepared in Comparative Example 1 were prepared respectively, and their properties were measured.

[0081] (1) Determination of superoxide anion radical scavenging rate

[0082] The superoxide anion radical scavenging rate was determined by the pyrogallol method, as follows: 1 mL (1 mmol / mL) of pyrogallol solution and 3 mL (pH 8.2) of Tris-HCl buffer were placed in a 10 mL brown volumetric flask, and 2 g of appropriately diluted oil sample were added to make the volume to 10 mL. After thorough mixing, the mixture was reacted at 37°C for 10 min, and then 0.4 mL of pyrogallol solution was transferred and shaken. After the reaction reached 4 min, 1.0 mL of concentrated hydrochloric acid was used to stop the reaction, and the absorbance was measured at 320 nm.

[0083] The scavenging rate of superoxide anion radicals = (A0-A1) / A0×100%. In the formula, A1 is the absorbance of the sample solution; A0 is the absorbance of the distilled water.

[0084] Test results:

[0085] Depend on Figure 4 It can be seen that the encapsulated grape seed essential oil microcapsules have a higher ability to scavenge superoxide anion free radicals than untreated grape seed essential oil. With the increase in the mass concentration of grape seed essential oil, the scavenging rate of superoxide anion free radicals of both microcapsules increased significantly, and the antioxidant capacity of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules was significantly higher than that of β-cyclodextrin grape seed essential oil microcapsules.

[0086] (2) Determination of hydroxyl radical scavenging rate

[0087] The hydroxyl radical scavenging rate was determined using the salicylic acid method. 2g of appropriately diluted oil sample was added to a test tube, followed by 2.0mL of 9mmol / L FeSO₄ and 2.0mL of 6mmol / L H₂O₂ solutions. The mixture was allowed to stand at room temperature for 10 minutes. 2.0mL of 9mmol / L salicylic acid solution was then added to the test tube, mixed thoroughly, and allowed to stand for 30 minutes. The absorbance of the two microcapsules was measured at 510nm, using distilled water as a control. The hydroxyl radical scavenging rate (SA) (%) was calculated using the following formula:

[0088]

[0089] Where: A0 is the absorbance without adding sample; A1 is the absorbance with adding sample.

[0090] Test results:

[0091] Depend on Figure 5 It can be seen that the encapsulated grape seed essential oil microcapsules have a higher scavenging capacity for hydroxyl radicals than untreated grape seed essential oil. Grape seed essential oil has different scavenging capacities for hydrocarbon free radicals at different concentrations. As the concentration of grape seed essential oil increases, the scavenging rate of the treated grape seed essential oil also increases. Furthermore, the antioxidant capacity of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules is higher.

[0092] (3) DPPH free radical scavenging ability

[0093] Dissolve DPPH reagent in isopropanol solution and dilute it. 2g of appropriately diluted oil sample and 2mL 1×10 -4 mM DPPH solution (dissolved in isopropanol) was mixed and incubated at room temperature in the dark for 30 min. Trolox was used as a standard substance and the absorbance (OD 517 ) The linear regression equation curve of Trolox concentration was used to calculate the equivalent antioxidant activity of the microcapsule samples against Trolox.

[0094] Test results:

[0095] Figure 6 The left side shows the standard curve obtained by Trolox's ability to remove DPPH: y = -0.007x + 0.7405, R 2 =0.9994. Figure 6 As can be seen from the right, the DPPH scavenging ability of grape seed essential oil was greatly improved after microencapsulation. The antioxidant activity of the microcapsules encapsulated with β-cyclodextrin was 144.45 μM TE / 100 g oil, and the antioxidant activity of the microcapsules encapsulated with hydroxypropyl-β-cyclodextrin was 185.58 μM TE / 100 g oil.

[0096] (4) Determination of total phenol content

[0097] Weigh 1.5 g of microcapsule sample and add a 90% methanol-water solution. Vortex thoroughly to dissolve the sample. Centrifuge the mixture at high speed for 5 minutes, collect the supernatant, repeat this twice, transfer the supernatant to a 10 mL volumetric flask, and dilute to 10 mL with a 90% methanol-water solution. Place the flask in a refrigerator until ready to use. Add 1 mL of the extract, 1 mL of folin, 5 mL of 7.5% sodium carbonate solution, and 3 mL of ddH2O to two test tubes, respectively. Measure the absorbance at 765 nm and record the data.

[0098] Using gallic acid as the standard substance, draw a standard curve of concentration and absorbance.

[0099] Test results:

[0100] Figure 7 The left side is the standard curve of total phenols: y = 0.9984x-0.005, R 2 =0.9998. Figure 7 As can be seen on the right, the polyphenol content in hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules is significantly higher than that in β-cyclodextrin grape seed essential oil microcapsules. The total phenol content of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules is about 220μg GAE / g, while the total phenol content of β-cyclodextrin grape seed essential oil is about 105μg GAE / g. The study found that the antioxidant properties of grape seed essential oil are correlated with the content of phenolic substances. The higher the total phenol content in the sample, the stronger the antioxidant capacity of grape seed essential oil. The results show that the total phenol content of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules is significantly higher than that of β-cyclodextrin grape seed essential oil microcapsules. Therefore, it can be seen that under the same storage time, the antioxidant capacity of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules is higher than that of β-cyclodextrin grape seed essential oil microcapsules.

[0101] (5) Determination of total flavonoid content

[0102] Take 1g of microcapsules and place them in a centrifuge tube. Add 3mL of 5% NaNO2 solution, 3mL of 10% Al(NO3)3 solution, and 4mL of 2mol / LNaOH in sequence. Mix thoroughly, react in the dark for 15min, and measure the absorbance at 510nm.

[0103] Using troxerutin as the standard substance, a standard curve of concentration and absorbance was drawn.

[0104] Test results:

[0105] Figure 8 The left side is the standard curve of total flavonoids: y = 0.0114x + 0.0084, R 2 =0.9991. Figure 8As can be seen on the right, the total flavonoid content of different grape seed essential oil microcapsules varied significantly. The total flavonoid content of hydroxypropyl-β-cyclodextrin microcapsules was 35.16 μg / g, while that of β-cyclodextrin grape seed microcapsules was 18.39 μg / g. These results indicate that the total flavonoid content of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules was significantly higher than that of β-cyclodextrin grape seed essential oil microcapsules.

[0106] (6) Characterization of the stability of grape seed essential oil microcapsules

[0107] (6.1) Determination of peroxide value

[0108] The dried microcapsule samples were placed in a beaker and stored in a biochemical incubator at 60°C for 24 days. The peroxide value was measured every 6 days using a titration method for the oil sample, following the national standard for peroxide value determination.

[0109] Test results:

[0110] Peroxide value is another specific indicator of oil oxidation reaction. Figure 9 It can be seen that with the extension of storage time, the peroxide value of the two grape seed essential oil microcapsules continued to increase, among which the peroxide value of hydroxypropyl-β-cyclodextrin grape seed essential oil microcapsules was always lower than that of β-cyclodextrin grape seed essential oil capsules.

[0111] (6.2) Effect of light on microcapsules

[0112] The microcapsule samples were placed in colorless, transparent sealed bottles. One group was placed in the dark, while the other group was placed in the light. Both groups were kept for 40 days. Every 8 days, the sealed bottles were removed and the retention rate of grape seed essential oil in the samples was measured.

[0113] Test results:

[0114] Depend on Figure 10 It can be seen that the retention rates of both decreased with the extension of storage time. Under light-proof conditions, the retention rate of grape seed essential oil was generally higher than that under light conditions; and the retention rate of grape seed essential oil encapsulated in hydroxypropyl-β-cyclodextrin was higher than that in β-cyclodextrin, and the stability was better.

[0115] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for preparing high antioxidant grape seed essential oil microcapsules, characterized in that: The following steps are involved: A hydroxypropyl-β-cyclodextrin aqueous solution is used as the wall material solution, and a mixture of grape seed essential oil and ethanol is used as the core material; the core material is added to the wall material solution for embedding, and dispersed and homogenized to form an emulsion; the emulsion is allowed to stand, filtered, and freeze-dried to produce grape seed essential oil microcapsules; The mass ratio of the embedded core to the wall is 1:6-8, the time is 40-60 minutes, and the temperature is 30-50°C.

2. The preparation method according to claim 1, characterized in that The wall material solution is prepared by mixing hydroxypropyl-β-cyclodextrin and water at a ratio of 1 g:1.5-2 mL at 55-65° C.

3. The preparation method according to claim 1, characterized in that The core material is prepared by mixing grape seed essential oil and ethanol in equal volume ratio at 30-40° C.; the concentration of the ethanol is 90-100 wt %.

4. The preparation method according to claim 1, characterized in that The speed of the dispersion and homogenization is 1000-2000 rpm, the time is 20-30 minutes, and the temperature is 35-45°C.

5. The preparation method according to claim 1, characterized in that The temperature of the standing state is 4-5° C. and the time is 8-12 hours.

6. The preparation method according to claim 1, characterized in that After the filtration, the mixture is washed with anhydrous ethanol for 3 to 4 times.

7. The preparation method according to claim 1, characterized in that The freeze-drying temperature is -60 to -40°C, the air pressure is less than 10 Pa, and the time is 24 to 48 hours.

8. The preparation method according to claim 1, characterized in that The method further comprises sieving and crushing the grape seed essential oil microcapsules to a particle size of 80 mesh or less after freeze-drying.

9. High antioxidant grape seed essential oil microcapsules prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the high antioxidant grape seed essential oil microcapsules according to claim 9 in the preparation of food, cosmetics or medicines.

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