Blackcurrant extract and preparation method thereof

Abstract

The invention relates to the technical field of blackcurrant extraction materials, in particular to a blackcurrant extract and a preparation method thereof. The preparation method of the blackcurrant extract comprises the following steps: crushing and enzymolysis: crushing blackcurrant fruits into fruit pulp, and adding cellulase, pectinase, carotenoid and water into the fruit pulp for enzymolysis to obtain enzymatic hydrolysate; centrifugal filtration: performing centrifugal filtration on the enzymatic hydrolysate to obtain an extracting solution; performing vacuum concentration: performing vacuum concentration on the extracting solution to obtain a concentrated solution; freeze-drying: freeze-drying the concentrated solution to obtain the blackcurrant extract. The carotenoid is added, the freeze drying technology is adopted, the carotenoid scavenges free radicals, the freeze drying technology reduces the oxidative decomposition of anthocyanin in the production process by reducing the activity of oxidase and evaporating water, and therefore the yield of the blackcurrant extract and the purity of the anthocyanin are improved.

Description

Technical Field

[0001] The present application relates to the technical field of black currant extract materials, and in particular to a black currant extract and a preparation method thereof. Background Art

[0002] Blackcurrant, the fruit is black, spherical, sweet and sour, and rich in nutrition. Blackcurrant fruit is rich in anthocyanins, a class of water-soluble natural pigments widely found in plants. Anthocyanins, as a natural edible pigment, are safe, non-toxic, abundant in resources, and have certain nutritional and pharmacological effects. They have great application potential in food, cosmetics, medicine, etc. Therefore, a variety of health products have been developed using blackcurrant fruit.

[0003] In the existing technology, blackcurrant is mostly extracted by water, and then cellulase and pectinase are added to destroy the cell wall, release anthocyanins from the cells, and increase the content of anthocyanins in the blackcurrant extract. However, in the actual production process, in order to ensure the activity of cellulase and pectinase during the enzymatic hydrolysis process, the entire enzymatic hydrolysis process is kept at 35-45°C. In the subsequent concentration and drying process, anthocyanins are constantly exposed to air and high temperatures, and a small amount of anthocyanins will be oxidatively decomposed. Therefore, there is room for further improvement in the content of anthocyanins in the final blackcurrant extract. Summary of the invention

[0004] In order to solve the problem of how to increase the anthocyanin content in black currant extract, the present application provides a method for preparing black currant extract, which reduces the oxidative decomposition of anthocyanins during the production process by adding carotenoids and freeze-drying, thereby increasing the final black currant extract content and the purity of anthocyanins therein.

[0005] In a first aspect, the present application provides a method for preparing a blackcurrant extract, using the following technical solution: A method for preparing a blackcurrant extract comprises the following steps: Crushing and enzymolysis: crush the blackcurrant fruit into pulp, add cellulase, pectinase, carotenoid and water into the pulp for enzymolysis to obtain enzymolysis solution; Centrifugal filtration: centrifugally filtration the enzymatic hydrolyzate to obtain an extract; Concentrating under reduced pressure: concentrating the extract under reduced pressure to obtain a concentrated solution; Freeze drying: freeze drying the concentrate to obtain black currant extract.

[0006] By adopting the above technical solution, carotenoids are added during the enzymatic hydrolysis process. Carotenoids contain many double bonds, which can inhibit lipid peroxidation, scavenge free radicals, and reduce the damage of oxidative stress to anthocyanins, thereby protecting the stability and activity of anthocyanins. In addition, carotenoids and anthocyanins often coexist in plants, and can enhance each other's biological activity through synergistic effects.

[0007] In addition, during the freeze-drying process, the extract is first quickly frozen. This step can quickly fix the structure of anthocyanins and prevent structural changes or oxidative decomposition due to temperature changes during the cooling process. During the freeze-drying process, anthocyanins are always in a low-temperature environment. Low temperature can significantly reduce the activity of oxidases, thereby reducing the oxidative decomposition of anthocyanins due to enzymatic reactions. As water evaporates, the concentration of anthocyanins gradually increases. Although the reduction in water increases the concentration of free radicals, the increase is much smaller than the increase in anthocyanins, thereby further reducing the possibility of oxidation reactions.

[0008] The present application increases the yield of black currant extract and the purity of anthocyanins by adding carotenoids and adopting freeze-drying technology, wherein carotenoids scavenge free radicals, and freeze-drying technology reduces the oxidative decomposition of anthocyanins in the production process by reducing the activity of oxidase and the evaporation of water.

[0009] Preferably, in the step of crushing and enzymolysis, the carotenoids include at least one of astaxanthin, β-carotene and lutein.

[0010] By adopting the above technical solutions, astaxanthin is a more powerful antioxidant than beta-carotene, and its antioxidant capacity exceeds that of other carotenoids. During the crushing and enzymatic hydrolysis process, astaxanthin can more effectively scavenge free radicals and prevent oxidative degradation of active ingredients.

[0011] β-carotene is a powerful antioxidant that protects cells from free radical damage. During the crushing and enzymatic hydrolysis process, β-carotene can reduce the degradation of other active ingredients caused by oxidation, thereby maintaining the stability and nutritional value of the extract.

[0012] Lutein also has antioxidant properties and improves the stability of the extract during the crushing and enzymatic hydrolysis process.

[0013] Preferably, in the step of crushing and enzymolysis, the mass ratio of the blackcurrant fruit to astaxanthin is 1000:0.5-1.

[0014] By adopting the above technical solution, the antioxidant activity of astaxanthin is better than that of β-carotene and lutein. Therefore, when adding astaxanthin alone, a smaller amount can be added to provide sufficient antioxidant protection, effectively remove free radicals that may be generated during the enzymatic hydrolysis process, reduce the oxidative decomposition of anthocyanins, and maintain the stability and yield of anthocyanins.

[0015] Preferably, in the step of crushing and enzymolysis, the mass ratio of the blackcurrant fruit to β-carotene is 1000:0.8-1.5.

[0016] By adopting the above technical solution, within this ratio range, the added β-carotene can provide sufficient antioxidant protection, effectively remove free radicals that may be generated during the enzymatic hydrolysis process, reduce the oxidative decomposition of anthocyanins, and maintain the stability and yield of anthocyanins. This ratio not only ensures the antioxidant effect, but also takes economic factors into consideration. Too high an amount of β-carotene added may lead to increased costs, but at this ratio, both the antioxidant effect can be achieved and the cost can be kept relatively low.

[0017] Preferably, in the step of crushing and enzymolysis, the mass ratio of the blackcurrant fruit to lutein is 1000:1-2.

[0018] By adopting the above technical solution, the antioxidant activity of lutein is lower than that of β-carotene and astaxanthin. Therefore, when lutein is added alone, more amount needs to be added to provide sufficient antioxidant protection, effectively remove free radicals that may be generated during the enzymatic hydrolysis process, reduce the oxidative decomposition of anthocyanins, and maintain the stability and yield of anthocyanins.

[0019] Preferably, ethanol is also added in the step of crushing and enzymolysis.

[0020] By adopting the above technical solution, ethanol as an organic solvent can effectively promote the dissolution of carotenoids and anthocyanins in the solution. This helps to increase the contact opportunities between carotenoids and anthocyanins, and promotes the interaction and binding between them. This binding may help to form a stable complex, thereby further reducing the oxidative decomposition of anthocyanins.

[0021] At appropriate concentrations, ethanol can act as an enhancer of enzyme activity. It can change the enzyme's microenvironment, such as the ionic strength and pH value of the solution, thereby improving the enzyme's catalytic efficiency and selectivity. For cellulase and pectinase, the addition of ethanol can promote their decomposition of cellulose and pectin in blackcurrant fruit. This helps to better release and retain target ingredients such as anthocyanins in blackcurrant fruit.

[0022] Through the combined effect of the above two points, the addition of ethanol can improve the extraction efficiency of anthocyanins in blackcurrant fruit. More anthocyanins are released and retained in the solution, thereby increasing the anthocyanin content in the final product. At the same time, due to the solvent effect of ethanol and the protective effect of carotenoids, the extraction of other non-target components and impurities may be reduced, further improving the purity of the final product.

[0023] Preferably, the concentration of ethanol in the enzymatic hydrolysate is 10-20 wt %.

[0024] By adopting the above technical scheme, within this concentration range, ethanol can effectively promote the dissolution of carotenoids and anthocyanins in the solution, thereby increasing the interaction and binding opportunities between them. This combination helps to form a stable complex to protect anthocyanins from oxidative decomposition. At an ethanol concentration of 10-20wt%, the activity of most enzymes can be enhanced, especially cellulase and pectinase. The addition of ethanol can change the microenvironment of the enzyme, improve the catalytic efficiency and selectivity of the enzyme, and then promote the decomposition of cellulose and pectin in blackcurrant fruit, thereby facilitating the release and extraction of anthocyanins.

[0025] Too high an ethanol concentration may damage the protein structure of the enzyme, causing the enzyme to become inactive. In particular, when the ethanol concentration approaches or exceeds the tolerance limit of some enzymes, the catalytic ability of the enzyme will be significantly reduced, thereby affecting the decomposition effect of blackcurrant fruit. Too high an ethanol concentration may also lead to enhanced interactions between anthocyanin molecules, forming aggregates, thereby reducing their solubility.

[0026] Preferably, in the freeze-drying step, the freezing temperature is -35°C to -45°C.

[0027] By adopting the above technical solution, within this temperature range, the blackcurrant extract can quickly reach below freezing point and achieve rapid freezing. Rapid freezing helps to form tiny ice crystals, thereby reducing the damage of ice crystals to bioactive substances. The freeze-drying process includes a sublimation step, that is, the ice crystals are directly converted into water vapor without passing through the liquid state. Within the temperature range of -35°C to -45°C, it can be ensured that the ice crystals have sufficient driving force to overcome their surface tension during the sublimation process and achieve effective water removal. At the same time, it can also reduce the growth and contamination risks of microorganisms and ensure the safety and stability of the product.

[0028] Preferably, in the freeze-drying step, the freeze-drying time is 40-48 hours.

[0029] By adopting the above technical solution, the freeze drying time directly affects the drying effect and final quality of the product. If the time is too short, the moisture removal may not be complete, and the product may contain a high amount of residual moisture, which will affect the stability and shelf life of the product. If the time is too long, it may increase energy consumption, reduce production efficiency, and may cause product quality to decline, such as color changes, loss of nutrients, etc. Selecting 40-48 hours, this time range can ensure that the moisture in the product is effectively removed, while avoiding the decline in product quality caused by too long drying time.

[0030] In a second aspect, the present application provides a black currant extract, which adopts the following technical solution: A blackcurrant extract is prepared by any one of the above preparation methods.

[0031] By adopting the above technical solution, the black currant extract and the above method for preparing the black currant extract have the same advantages over the prior art, which will not be described in detail here.

[0032] In summary, this application has the following beneficial effects: 1. The present invention increases the yield and purity of black currant extract by adding carotenoids and adopting freeze-drying technology, wherein carotenoids scavenge free radicals and freeze-drying technology reduces the oxidative decomposition of anthocyanins in the production process by reducing the activity of oxidase and evaporation of water; 2. The present application adds ethanol during crushing and enzymolysis, which can improve the extraction efficiency of anthocyanins in blackcurrant fruits. More anthocyanins are released and retained in the solution, thereby increasing the anthocyanin content in the final product. At the same time, due to the solvent effect of ethanol and the protective effect of carotenoids, the extraction of other non-target components and impurities may be reduced, further improving the purity of the final product.

[0033] Reference numerals Figure 1 It refers to the high performance liquid chromatogram of some anthocyanins when the purity of anthocyanins in blackcurrant extract is determined in this application. DETAILED DESCRIPTION

[0034] The raw materials in this application include the following parts: Blackcurrant: commercially available product; Cellulase: a commercially available product with CAS number 9004-34-6; Pectinase: a commercially available product with CAS number 9032-75-1 was used; Astaxanthin: a commercial product with CAS number 472-61-7 was used; β-carotene: a commercial product with CAS number 7235-40-7; Lutein: a commercial product with CAS number 127-40-2 was used; Ethanol: a commercially available product with CAS number 64-17-5 was used; Water: a commercial product with CAS number 7732-18-5 was used; The present application is further described in detail below in conjunction with embodiments and comparative examples.

[0035] Example 1 A production process of blackcurrant extract comprises the following steps: Crushing and enzymolysis: crush 1 kg of blackcurrant fruit into pulp, add 1 g of cellulase, 1 g of pectinase, 1 g of astaxanthin and 200 g of water into the pulp for enzymolysis at a temperature of 40°C for 4 h to obtain an enzymolysis solution; Centrifugal filtration: The enzymatic hydrolysate was centrifuged twice, first centrifuged at 2000 rpm for 5 min and then filtered under a 500-mesh filter to obtain a filtrate, and then the filtrate was centrifuged at 10000 rpm for 5 min and filtered under a 1000-mesh filter to obtain an extract; Concentration under reduced pressure: The extract is concentrated under reduced pressure to obtain a concentrated solution, with a vacuum degree of -0.09Mpa; Freeze drying: freeze-dry the concentrate at a freezing temperature of -45°C and a drying time of 45 hours to obtain a black currant extract.

[0036] Embodiment 2-4 In Example 2-4, based on the preparation method of Example 1, the amount of astaxanthin added was adjusted, and the specific adjustment is shown in Table 1.

[0037] Comparative Example 1-2 Comparative Example 1-2 Based on the preparation method of Example 1, the amount of astaxanthin added was adjusted, and the specific adjustment is shown in Table 1.

[0038] Table 1 Astaxanthin and performance test table of Examples 1-4 and Comparative Examples 1-2 project Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Astaxanthin / g 1 0.5 0.7 0.9 0.4 / Yield / g 18.3 15.2 16.9 18.4 14.5 14.2 Anthocyanin purity / % 86.5 83.1 85.2 86.4 81.0 80.6 Performance Test The blackcurrant extracts of Examples 1-4 and Comparative Examples 1-2 were subjected to the following performance tests. The test results are shown in Table 1.

[0039] 1. Output The weight of the obtained black currant extract was measured to obtain the yield.

[0040] 2. Purity See also Figure 1, the content of anthocyanins in blackcurrant extract was determined by high performance liquid chromatography to obtain the corresponding purity. Chromatographic conditions: chromatographic column: WaterBEH-C18 (2.1mm×100mm, 1.7μm); mobile phase A: 3% formic acid in double distilled water, mobile phase B: 100% acetonitrile; detection wavelength 520nm; flow rate 1.0mL / min; column temperature 30℃; injection volume 20μL.

[0041] Referring to Table 1, it can be seen from the comparison between Examples 1-4 and Comparative Example 1-2 that the yield and anthocyanin purity of Comparative Example 2 are lower than those of Examples 1-4, indicating that the addition of astaxanthin can effectively reduce the oxidative decomposition of anthocyanins during the extraction process of blackcurrant; As the amount of astaxanthin added continued to increase, the yield of black currant extract and the purity of anthocyanins continued to increase until they reached a stable level. This may be because as the amount of astaxanthin added continued to increase, astaxanthin continued to interact with anthocyanins and scavenge free radicals to help reduce the oxidative decomposition of anthocyanins during the extraction process, thereby increasing the yield of black currant extract and the purity of anthocyanins.

[0042] Embodiment 5-7 Example 5 Based on the preparation method of Example 1, 1 g of astaxanthin is replaced with 1.5 g of β-carotene, and the other conditions remain unchanged.

[0043] In Example 6-7, based on the preparation method of Example 5, the amount of β-carotene added was adjusted, and the specific adjustment is shown in Table 2.

[0044] Comparative Examples 3-4 Comparative Example 3-4 Based on the preparation method of Example 5, the amount of β-carotene added was adjusted, and the specific adjustment is shown in Table 2.

[0045] The blackcurrant extracts of Examples 5-7 and Comparative Examples 3-4 were subjected to the above performance tests, and the test results are shown in Table 2.

[0046] Table 2 The amount of β-carotene added and the performance test data of Example 1, Examples 5-7 and Comparative Examples 3-4 project Example 1 Example 5 Example 6 Example 7 Comparative Example 3 Comparative Example 4 β-carotene / g / 1.5 0.8 1.2 0.8 1.8 Yield / g 18.3 17.6 15.5 16.3 14.7 17.7 Anthocyanin purity / % 86.5 85.9 83.4 84.3 78.0 85.8 Referring to Table 2, it can be seen from the comparison of Example 1, Examples 5-7 and Comparative Examples 3-4 that as the amount of β-carotene added increases, the yield of blackcurrant extract and the purity of anthocyanins increase until they stabilize. This may be because as the amount of β-carotene added increases, β-carotene continues to interact with anthocyanins to remove free radicals, thereby helping to reduce the oxidative decomposition of anthocyanins during the extraction process, thereby increasing the yield of blackcurrant extract and the purity of anthocyanins. Since the antioxidant activity of β-carotene is worse than that of astaxanthin, the amount of β-carotene added must be higher than that of astaxanthin to effectively reduce the oxidative decomposition of anthocyanins.

[0047] Examples 8-10 Example 8 Based on the preparation method of Example 1, 1g of astaxanthin is replaced with 2g of lutein, and the other conditions remain unchanged.

[0048] In Examples 9-10, based on the preparation method of Example 8, the amount of lutein added was adjusted, and the specific adjustments are shown in Table 3.

[0049] Comparative Examples 5-6 Comparative Example 5-6 is based on the preparation method of Example 8, and the amount of lutein added is adjusted. The specific adjustment is shown in Table 3.

[0050] The blackcurrant extracts of Examples 8-10 and Comparative Examples 5-6 were subjected to the above performance tests. The test results are shown in Table 3.

[0051] Table 3 Lutein addition amount and performance test data of Example 1, Examples 8-10 and Comparative Examples 5-6 project Example 1 Example 8 Example 9 Example 10 Comparative Example 5 Comparative Example 6 Lutein / g / 2 1 1.5 0.8 2.2 Yield / g 18.3 17.1 15.2 15.9 14.4 17.2 Anthocyanin purity / % 86.5 85.2 83.1 84.1 77.3 85.3 Referring to Table 3, it can be seen from the comparison of Example 1, Examples 8-10 and Comparative Examples 5-6 that as the amount of lutein added increases, the yield of blackcurrant extract and the purity of anthocyanins increase until they stabilize. This may be because as the amount of lutein added increases, lutein continuously interacts with anthocyanins to remove free radicals, thereby helping to reduce the oxidative decomposition of anthocyanins during the extraction process, thereby increasing the yield of blackcurrant extract and the purity of anthocyanins. Since lutein has a poorer antioxidant property than astaxanthin, the amount of lutein added must be higher than the amount of astaxanthin added to effectively reduce the oxidative decomposition of anthocyanins.

[0052] Examples 11-12 In Examples 11-12, based on the preparation method of Example 1, the freezing temperature is adjusted, and the specific adjustments are shown in Table 4.

[0053] Comparative Examples 7-8 In Comparative Examples 7-8, based on the preparation method of Example 1, the freezing temperature was adjusted, and the specific adjustments are shown in Table 4.

[0054] The blackcurrant extracts of Examples 11-12 and Comparative Examples 7-8 were subjected to the above performance tests, and the test results are shown in Table 4.

[0055] Table 4 Refrigeration temperature and performance test data of Example 1, Examples 11-12 and Comparative Examples 7-8 project Example 1 Embodiment 11 Example 12 Comparative Example 7 Comparative Example 8 Freezing temperature / ℃ -45 -35 -40 -30 -50 Yield / g 18.3 16.2 17.5 14.8 18.4 Anthocyanin purity / % 86.5 84.2 85.8 82.2 86.7 Referring to Table 4, it can be seen from the comparison between Example 1, Examples 11-12 and Comparative Examples 7-8 that as the freezing temperature continues to increase, the yield and anthocyanin purity of the blackcurrant extract continue to increase until they stabilize, which may be because as the freezing temperature continues to increase, the blackcurrant extract can quickly reach below freezing point and achieve rapid freezing. Rapid freezing helps to form tiny ice crystals, thereby reducing the damage of ice crystals to biologically active substances. In addition, the driving force of ice crystals continues to increase during the sublimation process to overcome their surface tension and achieve effective water removal.

[0056] Examples 13-14 In Examples 13-14, based on the preparation method of Example 1, the drying time was adjusted, and the specific adjustments are shown in Table 5.

[0057] Comparative Examples 9-10 Comparative Examples 9-10 are based on the preparation method of Example 1, and the drying time is adjusted. The specific adjustments are shown in Table 5.

[0058] The blackcurrant extracts of Examples 13-14 and Comparative Examples 9-10 were subjected to the above performance tests. The test results are shown in Table 5.

[0059] Table 5 Drying time and performance test data of Example 1, Examples 13-14 and Comparative Examples 9-10 project Example 1 Example 13 Embodiment 14 Comparative Example 9 Comparative Example 10 Drying time / h 45 40 48 35 50 Yield / g 18.3 16.0 17.3 14.9 14.7 Anthocyanin purity / % 86.5 84.0 85.0 82.3 82.5 Referring to Table 5, it can be seen from the comparison of Example 1, Examples 13-14 and Comparative Examples 9-10 that as the drying time continues to increase, the yield of the black currant extract and the purity of anthocyanins show a trend of first increasing and then decreasing. This may be because as the drying time continues to increase, the moisture in the black currant extract is continuously removed, and the stability of anthocyanins in the black currant extract is getting better and better, thereby continuously improving the yield of the black currant extract and the purity of anthocyanins; after exceeding a certain range, long-term drying will destroy the molecular structure of anthocyanins, thereby causing a decline in product quality.

[0060] Examples 15-17 Example 15 is based on the preparation method of Example 1, and ethanol is further added during the crushing and enzymatic hydrolysis step, and the final concentration of ethanol in the enzymatic hydrolyzate is 15%.

[0061] In Examples 16-17, based on the preparation method of Example 13, the mass concentration of ethanol was adjusted, and the specific adjustments are shown in Table 6.

[0062] In Comparative Examples 11-12, based on the preparation method of Example 13, the mass concentration of ethanol was adjusted, and the specific adjustments are shown in Table 6.

[0063] The blackcurrant extracts of Examples 15-17 and Comparative Examples 11-12 were subjected to the above performance tests. The test results are shown in Table 6.

[0064] Table 6: Mass concentration and performance test data of ethanol in Example 1, Examples 15-17 and Comparative Examples 11-12 Referring to Table 6, by comparing Example 1, Examples 15-17 and Comparative Examples 11-12, it can be seen that compared with Example 1, the yield and anthocyanin purity of the black currant extract of Examples 15-17 are slightly lower than those of Example 1; this indicates that adding a certain amount of ethanol can better promote the extraction of black currant fruit.

[0065] As the ethanol mass concentration continued to increase, the yield of black currant extract and the purity of anthocyanins showed a trend of first increasing and then decreasing. This may be because as the ethanol mass concentration continued to increase, ethanol could effectively promote the dissolution of carotenoids and anthocyanins in the solution, and could also increase the activity of cellulase and pectinase; when it exceeded a certain range, ethanol might destroy the biological activity of cellulase and pectinase, and instead reduce the yield of black currant extract and the purity of anthocyanins.

[0066] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. A method for preparing a blackcurrant extract, characterized in that: The following steps are involved: Crushing and enzymolysis: crush the blackcurrant fruit into pulp, add cellulase, pectinase, carotenoid and water into the pulp for enzymolysis to obtain enzymolysis solution; Centrifugal filtration: centrifugally filtration the enzymatic hydrolyzate to obtain an extract; Concentrating under reduced pressure: concentrating the extract under reduced pressure to obtain a concentrated solution; Freeze drying: freeze drying the concentrate to obtain black currant extract.

2. The method for preparing the blackcurrant extract according to claim 1, characterized in that: In the step of crushing and enzymolysis, the carotenoids include at least one of astaxanthin, β-carotene and lutein.

3. The method for preparing the blackcurrant extract according to claim 2, characterized in that: In the step of crushing and enzymolysis, the mass ratio of the blackcurrant fruit to astaxanthin is 1000:0.5-1.

4. The method for preparing the blackcurrant extract according to claim 2, characterized in that: In the step of crushing and enzymolysis, the mass ratio of the blackcurrant fruit to beta-carotene is 1000:0.8-1.

5.

5. The method for preparing the blackcurrant extract according to claim 2, characterized in that: In the step of crushing and enzymolysis, the mass ratio of the blackcurrant fruit to lutein is 1000:1-2.

6. The method for preparing the blackcurrant extract according to claim 1, characterized in that: During the crushing and enzymatic hydrolysis step, ethanol is also added.

7. The method for preparing the blackcurrant extract according to claim 6, characterized in that: The concentration of ethanol in the enzymatic hydrolyzate is 10-20wt%.

8. The method for preparing the blackcurrant extract according to claim 1, characterized in that: In the freeze-drying step, the freezing temperature is -35°C to -45°C.

9. The method for preparing the blackcurrant extract according to claim 8, characterized in that: In the freeze-drying step, the freeze-drying time is 40-48 hours.

10. A blackcurrant extract, characterized in that: The blackcurrant extract is prepared by the preparation method of the blackcurrant extract according to any one of claims 1 to 9.

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