A fragrance composition based on blueberry extract and a method for its preparation

Abstract

This invention discloses a fragrance composition based on blueberry extract and its preparation method, belonging to the field of daily chemical fragrance preparation technology. The fragrance composition comprises the following raw materials in parts by weight: 14-20 parts by weight of blueberry extract encapsulation, 50-60 parts by weight of deionized water, 3-4 parts by weight of surfactant, and 1-2 parts by weight of co-surfactant. This invention mixes and stirs modified poly(L-DOPA)-encapsulated blueberry extract, deionized water, surfactant, and co-surfactant to form the fragrance composition, avoiding the defects caused by high-temperature extraction methods such as steam extraction, resulting in a fragrance composition with a longer-lasting fragrance effect.

Description

Technical Field

[0001] This invention belongs to the field of daily chemical fragrance preparation technology, specifically relating to a fragrance composition based on blueberry extract and its preparation method. Background Technology

[0002] Fragrances play an increasingly important role in modern life. Whether in food, cosmetics, detergents, perfumes, or air fresheners, fragrances not only give products a unique scent but also influence consumers' perceptions and purchasing decisions. The main functions of fragrances include: (1) Fragrances can significantly enhance the market value of products. Consumers often have a strong reaction to aromas, and pleasant aromas can enhance the attractiveness of products, thereby promoting sales. For example, the aromas of foods such as chocolate and coffee can often arouse consumers' appetites and increase their desire to buy; (2) Aromas can directly affect people's emotions and psychological state. Some aromas, such as lavender and vanilla, are considered to help relax and reduce stress, while citrus aromas are considered to be refreshing. Therefore, fragrances are also used in psychological and emotional therapy; (3) Fragrances can also be used to mask odors in products to improve the user experience. In detergents and washing agents, fragrances can mask the pungent odors caused by chemical components, making the products more pleasant; (4) Some fragrance components have antibacterial and antioxidant properties, which can help maintain the freshness of food and extend its shelf life. This is especially important in the food industry.

[0003] Fragrance sources are mainly divided into two categories: natural and synthetic. Synthetic fragrances are fragrances produced through chemical synthesis. The advantages of synthetic fragrances are their lower cost, better stability, and ability to create aromas that natural fragrances cannot achieve. For example, commonly used synthetic fragrances in perfumes, such as vanillin and ethyl vanillin, can simulate the characteristics of natural aromas. Natural fragrances refer to fragrances extracted from plants, animals, or minerals. Common sources of natural fragrances include: (1) Plant sources: Many fragrances come from the flowers, fruits, leaves, roots, bark, etc. of plants. For example, rose fragrance comes from rose petals, and peppermint fragrance comes from peppermint leaves; (2) Animal sources: Some fragrance ingredients, such as musk and ambergris, come from secretions in animals. These ingredients are often used in high-end perfumes, but due to ethical and environmental reasons, the use of animal-derived fragrances is gradually decreasing; (3) Mineral sources: Some minerals, such as styrax, can also be used in the production of fragrances.

[0004] Fragrances can be very complex, usually made up of a mixture of various fragrance components in a specific ratio. Fragrance components generally include the following categories: (1) Alcohols: such as vanillin, phenylethyl alcohol, α-terpineol and linalool, which have floral or sweet fragrance characteristics; (2) Terpenes: such as α-pinene, β-pinene or γ-terpinene; (3) Aldehydes: such as vanillin, cinnamaldehyde, etc., which usually have strong and unique aromas; (4) Esters: such as heptyl acetate, neryl acetate and geraniol propionate, which often have fruity aromas; (5) Ethers: such as aromatic ethers, which are often used to create complex aromas; (6) Ketones: such as vanillin, rose ketone, etc., which have unique fragrances.

[0005] Currently, the main methods for extracting fragrances include steam distillation, solvent extraction, and pressing. Steam distillation for fragrance production includes three methods: water distillation, water-based distillation, and steam distillation. Water distillation is generally preferred. This method utilizes the ease with which water molecules penetrate the fruit peel cells, displacing the essential oil and causing it to diffuse into the water. Under the action of steam, an azeotrope is formed and simultaneously distilled out. Solvent extraction relies on the extraction principle of organic solvents. Patent CN118207043A discloses a rosemary essential oil composition for slimming and firming the skin. This invention involves pulverizing and mixing rosemary, geranium, lemon, lotus leaf, and marjoram, adding an ethanol-water solution, heating, stirring, cooling, filtering, and concentrating the filtrate to obtain a concentrate; adding an extractant composed of an aqueous phase and an organic solvent, heating for extraction, removing the aqueous phase, and removing the organic solvent from the organic phase to finally obtain the rosemary essential oil composition. However, since most fragrances have low water solubility and high volatility, they are very unstable under adverse conditions such as oxygen, light and high temperature, resulting in a small amount of extracted fragrances that are not easy to preserve.

[0006] Patent CN117903875A discloses an endogenous aromatic plant fragrance, its preparation method, and atomized fragrance. This invention uses supercritical CO2 extraction to extract the fragrance. This method is costly, requires expensive equipment, and demands advanced operational skills, making it unsuitable for large-scale use.

[0007] Blueberries are a usable fruit rich in natural flavor components such as alcohols, esters, and terpenes. Extracting these components and preparing flavorings from blueberries offers advantages such as transparent sourcing and safe ingredients. Designing a method to avoid the negative effects of high-temperature volatilization and oxidation on the extraction of flavorings from blueberries, thereby ensuring a longer-lasting fragrance, is of great significance. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention mixes and stirs modified poly-L-DOPA-encapsulated blueberry extract, deionized water, surfactant, and co-surfactant to form a fragrance composition. This avoids the defects caused by high-temperature extraction methods such as steam extraction, resulting in a fragrance composition with a longer-lasting fragrance effect, thus solving the technical problems mentioned in the background art. Specifically, the technical solution of this invention includes the following:

[0009] A flavoring composition based on blueberry extract, the flavoring composition comprising the following raw materials in parts by weight:

[0010] 14-20 parts by weight of blueberry extract inclusions, 50-60 parts by weight of deionized water, 3-4 parts by weight of surfactant and 1-2 parts by weight of co-surfactant.

[0011] Furthermore, the preparation method of the blueberry extract inclusions includes the following steps:

[0012] Antibacterial monomers, enol compounds, ammonium persulfate and ethanol solution were mixed and dispersed in a weight ratio of 1:1 to 2:0.009:30 and reacted at a temperature of 30℃ to 40℃ for 60 min to 70 min to obtain hydroxyl-terminated modified eugenol prepolymer;

[0013] Hydroxyl-terminated modified eugenol prepolymer, levodopa, dichloromethane and esterification catalyst were mixed and ultrasonically dispersed in a weight ratio of 1:1 to 2:80:2.5 and reacted at 25°C for 15 to 20 hours to obtain esterified levodopa-prepolymer;

[0014] Esterified L-DOPA prepolymer, blueberry extract, and Tris-hydrochloride buffer were mixed and ultrasonically dispersed at a weight ratio of 2:1:100 and reacted at 25°C for 24-30 hours to obtain blueberry extract inclusions.

[0015] Furthermore, the antibacterial monomer includes eugenol.

[0016] Furthermore, the enol compound includes 3-buten-1-ol.

[0017] Furthermore, the esterification catalyst is composed of EDC hydrochloride, 4-dimethylaminopyridine, and triethylamine in a weight ratio of 1:0.7:0.8.

[0018] Furthermore, the preparation method of the blueberry extract includes the following steps:

[0019] Enzyme-loaded oxidized coconut shell activated carbon and blueberry pulp are mixed in a weight ratio of 1:80-100 to form a mixture. After adjusting the pH of the mixture to 4.5-5.0, it is hydrolyzed at 40-50℃ for 70-80 minutes to obtain a hydrolysate.

[0020] The hydrolysate and the mixed extractant were mixed at a weight ratio of 1:1 and extracted at 30℃~40℃ for 2h~3h to obtain the extract phase. The extract phase was then subjected to vacuum distillation and freeze drying to obtain the blueberry extract.

[0021] Furthermore, the preparation method of the enzyme-loaded oxidized coconut shell activated carbon includes the following steps:

[0022] Coconut shell powder, inorganic acid and purified water are mixed and impregnated in a weight ratio of 1:1 to 1.2:10 to 15 to obtain an impregnation solution. The impregnation solution is then pyrolyzed at 500℃ to 600℃ for 80 min to 90 min to obtain coconut shell activated carbon.

[0023] Activated coconut shell carbon and nitric acid solution are mixed at a weight ratio of 1:10-12 and oxidized for 4-5 hours to obtain oxidized coconut shell activated carbon.

[0024] Oxidized coconut shell activated carbon, phosphate buffer, hydrolase, ethylenediamine, EDC hydrochloride and N-hydroxysuccinimide were mixed and dispersed in a weight ratio of 5:100:0.1-0.2:0.1:5.5:5.5 and reacted at 25°C for 15-18 hours to obtain oxidized coconut shell activated carbon loaded with hydrolase.

[0025] Furthermore, the inorganic acid is phosphoric acid.

[0026] Furthermore, the mass concentration of the nitric acid solution is 40%.

[0027] Furthermore, the hydrolytic enzyme is xylanase.

[0028] Furthermore, the mixed extractant is composed of petroleum ether and ethyl acetate in a weight ratio of 4:2.

[0029] Furthermore, the surfactant includes Tween-80.

[0030] Furthermore, the co-surfactant includes ethanol.

[0031] A method for preparing a flavor composition based on blueberry extract, the method comprising the following steps:

[0032] The fragrance composition is obtained by mixing blueberry extract inclusions, deionized water, surfactant and co-surfactant and homogenizing at a speed of 9000-10000 r / min for 2-4 min.

[0033] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0034] This invention first involves high-temperature pyrolysis carbonization and oxidation of coconut shells with high cellulose content to prepare oxidized coconut shell activated carbon with low specific surface area. Cellulose is a natural high molecular polymer with a linear chain structure, which easily forms a microporous network structure after carbonization. Next, the hydrolytic enzymes that hydrolyze plant cell walls are cross-linked with ethylenediamine, immobilizing the hydrolytic enzymes on the surface of oxidized coconut shell activated carbon with a low specific surface area, resulting in enzyme-loaded oxidized coconut shell activated carbon. The advantage of immobilizing the hydrolysate on the surface of oxidized coconut shell activated carbon with a low specific surface area is that, on the one hand, the specific surface area of ​​the oxidized coconut shell activated carbon can be further reduced by the binding of the hydrolytic enzymes. The reduction in specific surface area weakens the adsorption of flavor components in blueberries by the oxidized coconut shell activated carbon. On the other hand, since the hydrolytic enzymes need to be inactivated at high temperatures after hydrolysis, high-temperature inactivation will cause volatilization and oxidative inactivation of flavor components in blueberries. By immobilizing the hydrolytic enzymes on the surface of oxidized coconut shell activated carbon, the enzyme-loaded oxidized coconut shell activated carbon can be removed by filtration after enzymatic hydrolysis, thus avoiding the high-temperature inactivation process and preserving the flavor components in blueberries to a greater extent. Blueberry pulp was hydrolyzed and cell walls were broken using oxidized coconut shell activated carbon loaded with hydrolytic enzymes. The resulting hydrolysate was then filtered and extracted with an extractant consisting of a mixture of petroleum ether and ethyl acetate to obtain the extract phase. The extract phase was then subjected to vacuum distillation to remove the extractant and freeze-dried to obtain blueberry extract. A hydroxyl-terminated eugenol prepolymer was obtained by reacting the antibacterial monomer eugenol with an enol-structured compound 3-buten-1-ol. This prepolymer was then reacted with L-DOPA to obtain an esterified L-DOPA-prepolymer. The esterified L-DOPA-prepolymer was then reacted with blueberry extract to obtain blueberry extract inclusions. The blueberry extract inclusions, deionized water, surfactant, and co-surfactant were mixed and stirred to form a fragrance composition. Hydroxyl-terminated modified eugenol prepolymers not only weaken the cross-linking density of L-DOPA oxidative self-polymerization through the steric hindrance structure of carbon chains and benzene rings, reducing the excessive cross-linking degree that would prevent the sustained release of encapsulated blueberry extract, but also, due to eugenol's own aroma and antibacterial activity, can synergistically enhance the aroma of blueberry extract and mitigate the short shelf life of the prepared fragrance composition caused by microbial spoilage through its antibacterial activity. Through the oxidative self-polymerization encapsulation effect of esterified L-DOPA-prepolymers, the sustained-release volatilization of blueberry extract is achieved, thereby prolonging the aroma retention of the prepared fragrance composition. Detailed Implementation

[0035] The technical solution of the present invention will be clearly and completely described below through embodiments. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] Unless otherwise stated, all raw materials and reagents used in this invention are commercially available or can be prepared by known methods.

[0037] Preparation Example 1:

[0038] The preparation method of enzyme-loaded oxidized coconut shell activated carbon includes the following steps:

[0039] Coconut shells were washed clean with water and then dried in a 60℃ oven until constant weight. After cooling to room temperature, the shells were removed and crushed using a crusher, then sieved through a 50-mesh sieve to obtain coconut shell powder. 20g of coconut shell powder and 20g of phosphoric acid were weighed and mixed, then 200g of purified water was added and stirred at 400 rpm for 40 minutes. The mixture was then placed in a 50℃ environment for 10 hours for impregnation. After impregnation, the impregnation solution was placed in a 110℃ oven for pre-treatment to remove water, and then placed in a tube furnace. Oxygen was purged using nitrogen, and a nitrogen atmosphere was maintained. The temperature was increased to 500℃ at a rate of 5℃ / min, and pyrolysis was performed at this temperature for 80 minutes. After pyrolysis, the mixture was allowed to cool naturally to room temperature, rinsed with deionized water until the pH of the rinse water was neutral, and then dried to obtain coconut shell activated carbon. 10g of coconut shell activated carbon was weighed and placed in a beaker, then 100g of 40% nitric acid solution was added and mixed. The mixture was then oxidized at 25℃ for 4 hours. After oxidation, the mixture was filtered and rinsed until the pH of the rinse water was neutral. The carbon was then dried to obtain oxidized coconut shell activated carbon (the specific surface area of ​​which was measured to be 307.46 m² using a static liquid nitrogen adsorption analyzer). 2 / g; The carboxylic acid group content of oxidized coconut shell activated carbon was determined to be 0.223 mmol / g using the Boehm titration method.

[0040] 5g of oxidized coconut shell activated carbon was added to 100g of phosphate buffer solution with a pH of 6.5 and dispersed using an ultrasonic disperser at 400W for 15min to obtain a dispersion. 0.1g of xylanase hydrolase, 0.1g of ethylenediamine, 5.5g of EDC hydrochloride, and 5.5g of N-hydroxysuccinimide were added to the dispersion and mixed. The mixture was then placed in a water bath at 25℃ and the reaction was timed for 15h. After the reaction, the mixture was filtered and washed with water until the pH of the wash water was neutral to obtain oxidized coconut shell activated carbon loaded with hydrolase.

[0041] Preparation Example 2:

[0042] The preparation method of enzyme-loaded oxidized coconut shell activated carbon includes the following steps:

[0043] Coconut shells were washed clean with water and then dried in a 60℃ oven until constant weight. After cooling to room temperature, the shells were removed and crushed using a crusher, then sieved through a 50-mesh sieve to obtain coconut shell powder. 20g of coconut shell powder and 22g of phosphoric acid were weighed and mixed, then 250g of purified water was added and stirred at 400 rpm for 45 minutes. The mixture was then placed in a 50℃ environment for 10 hours for impregnation. After impregnation, the impregnation solution was placed in a 110℃ oven for pre-treatment to remove water, and then placed in a tube furnace. Oxygen was purged using nitrogen, and a nitrogen atmosphere was maintained. The temperature was increased to 550℃ at a rate of 5℃ / min, and pyrolysis was performed at this temperature for 85 minutes. After pyrolysis, the mixture was allowed to cool naturally to room temperature, rinsed with deionized water until the pH of the rinse water was neutral, and then dried to obtain coconut shell activated carbon. 10g of coconut shell activated carbon was weighed and placed in a beaker, then 110g of a 40% nitric acid solution was added and mixed. The mixture was then oxidized at 30℃ for 4.5h. After oxidation, the mixture was filtered and rinsed until the pH of the rinse water was neutral. The carbon was then dried to obtain oxidized coconut shell activated carbon (the specific surface area of ​​which was measured to be 321.88 m² using a static liquid nitrogen adsorption analyzer). 2 / g; The carboxylic acid content of oxidized coconut shell activated carbon was determined to be 0.226 mmol / g using the Boehm titration method.

[0044] 5g of oxidized coconut shell activated carbon was added to 100g of phosphate buffer solution with a pH of 6.5 and dispersed using an ultrasonic disperser at 400W for 15min to obtain a dispersion. 0.15g of xylanase hydrolase, 0.1g of ethylenediamine, 5.5g of EDC hydrochloride, and 5.5g of N-hydroxysuccinimide were added to the dispersion and mixed. The mixture was then placed in a water bath at 25℃ and the reaction was timed for 17h. After the reaction, the mixture was filtered and washed with water until the pH of the wash water was neutral to obtain oxidized coconut shell activated carbon loaded with hydrolase.

[0045] Preparation Example 3:

[0046] The preparation method of enzyme-loaded oxidized coconut shell activated carbon includes the following steps:

[0047] Coconut shells were washed clean with water and then dried in a 60℃ oven until constant weight. After cooling to room temperature, the shells were removed and crushed using a crusher, then sieved through a 50-mesh sieve to obtain coconut shell powder. 20g of coconut shell powder and 24g of phosphoric acid were weighed and mixed, then 300g of purified water was added and stirred at 400 rpm for 50 minutes. The mixture was then placed in a 50℃ environment for 10 hours for impregnation. After impregnation, the impregnation solution was placed in a 110℃ oven for pre-treatment to remove water, and then placed in a tube furnace. Oxygen was purged using nitrogen, and a nitrogen atmosphere was maintained. The temperature was increased to 600℃ at a rate of 5℃ / min, and pyrolysis was performed at this temperature for 90 minutes. After pyrolysis, the mixture was allowed to cool naturally to room temperature, rinsed with deionized water until the pH of the rinse water was neutral, and then dried to obtain coconut shell activated carbon. 10g of coconut shell activated carbon was weighed and placed in a beaker, then 120g of 40% nitric acid solution was added and mixed. The mixture was then oxidized at 30℃ for 5 hours. After oxidation, the mixture was filtered and rinsed until the pH of the rinse water was neutral. The carbon was then dried to obtain oxidized coconut shell activated carbon (the specific surface area of ​​which was measured to be 330.27 m² using a static liquid nitrogen adsorption analyzer). 2 / g; The carboxylic acid content of oxidized coconut shell activated carbon was determined to be 0.228 mmol / g using the Boehm titration method.

[0048] 5g of oxidized coconut shell activated carbon was added to 100g of phosphate buffer solution with a pH of 6.5 and dispersed using an ultrasonic disperser at 400W for 15min to obtain a dispersion. 0.2g of xylanase hydrolase, 0.1g of ethylenediamine, 5.5g of EDC hydrochloride, and 5.5g of N-hydroxysuccinimide were added to the dispersion and mixed. The mixture was then placed in a water bath at 25℃ and the reaction was timed for 15–18h. After the reaction, the mixture was filtered and washed with water until the pH of the wash water was neutral to obtain oxidized coconut shell activated carbon loaded with hydrolase.

[0049] Preparation Example 4:

[0050] The preparation method of enzyme-loaded oxidized coconut shell activated carbon includes the following steps:

[0051] In Preparation Example 3, the amount of phosphoric acid was increased to 30 g, and the pyrolysis temperature was raised from 600 °C to 700 °C. The specific surface area of ​​the resulting oxidized coconut shell activated carbon, measured using a static liquid nitrogen adsorption analyzer, was 608.51 m². 2 / g; The carboxylic acid group content of oxidized coconut shell activated carbon was determined to be 0.311 mmol / g by the Boehm titration method;

[0052] The remaining preparation conditions were the same as in Preparation Example 3.

[0053] Preparation Example 5:

[0054] The preparation method of enzyme-loaded oxidized coconut shell activated carbon includes the following steps:

[0055] The xylanase hydrolase in Preparation Example 3 was replaced with cellulase, and the other preparation conditions were kept the same as in Preparation Example 3.

[0056] Preparation Example 6:

[0057] The preparation method of blueberry extract specifically includes the following steps:

[0058] Wash the blueberries, then grind and blend them together in a blender at a blueberry to water ratio of 1:50 to obtain blueberry pulp. Weigh 1 part by weight of the enzyme-loaded oxidized coconut shell activated carbon obtained in Preparation Example 1 and 80 parts by weight of the blueberry pulp, mix and stir to form a dispersion. Add dilute hydrochloric acid to the dispersion and slowly adjust the pH to 4.5-5.0. Then place it in a 40°C water bath for 70 minutes for constant temperature hydrolysis. After hydrolysis, first centrifuge to remove the blueberry residue, then filter to remove the enzyme-loaded oxidized coconut shell activated carbon to obtain the hydrolysate.

[0059] Equal parts by weight of the hydrolysate and the mixed extractant (composed of petroleum ether and ethyl acetate in a weight ratio of 4:2) were weighed, mixed and stirred, and placed in a water bath at 30°C with stirring at 200 rpm for 2 h. After extraction, the mixture was allowed to stand and separate into layers, and the extract phase was collected. The extract phase was then evaporated under reduced pressure in a rotary evaporator to remove the petroleum ether and ethyl acetate, and then freeze-dried in a freeze dryer to obtain the blueberry extract.

[0060] Preparation Example 7:

[0061] The preparation method of blueberry extract specifically includes the following steps:

[0062] Wash the blueberries, then grind and blend them together in a blender at a weight ratio of 1:50 to obtain blueberry pulp. Weigh 1 part by weight of the enzyme-loaded oxidized coconut shell activated carbon obtained in Preparation Example 2 and 90 parts by weight of the blueberry pulp, mix and disperse evenly to form a dispersion. Add dilute hydrochloric acid to the dispersion and slowly adjust the pH to 4.5-5.0. Then place it in a 45°C water bath for 75 minutes for constant temperature hydrolysis. After hydrolysis, first centrifuge to remove the blueberry residue, then filter to remove the enzyme-loaded oxidized coconut shell activated carbon to obtain the hydrolysate.

[0063] Equal parts by weight of the hydrolysate and the mixed extractant (composed of petroleum ether and ethyl acetate in a weight ratio of 4:2) were weighed, mixed and stirred, and placed in a water bath at 35°C with stirring at 200 rpm for 2.5 h. After extraction, the mixture was allowed to stand and separate into layers, and the extract phase was collected. The extract phase was then evaporated under reduced pressure in a rotary evaporator to remove the petroleum ether and ethyl acetate, and then freeze-dried in a freeze dryer to obtain the blueberry extract.

[0064] Preparation Example 8:

[0065] The preparation method of blueberry extract specifically includes the following steps:

[0066] Wash the blueberries, then grind and blend them together in a blender at a blueberry to water ratio of 1:50 to obtain blueberry pulp. Weigh 1 part by weight of the enzyme-loaded oxidized coconut shell activated carbon obtained in Preparation Example 1 and mix it with 100 parts by weight of the blueberry pulp to form a dispersion. Add dilute hydrochloric acid to the dispersion and slowly adjust the pH to 4.5-5.0. Then place it in a 50°C water bath for constant temperature hydrolysis for 80 minutes. After hydrolysis, first centrifuge to remove the blueberry residue, then filter to remove the enzyme-loaded oxidized coconut shell activated carbon to obtain the hydrolysate.

[0067] Equal parts by weight of hydrolysate and mixed extractant (composed of petroleum ether and ethyl acetate in a weight ratio of 4:2) were weighed, mixed and stirred, and placed in a water bath at 40°C with stirring at 200 rpm for 3 hours. After extraction, the mixture was allowed to stand and separate into layers, and the extract phase was collected. The extract phase was then evaporated under reduced pressure in a rotary evaporator to remove petroleum ether and ethyl acetate, and then freeze-dried in a freeze dryer to obtain blueberry extract.

[0068] Preparation Example 9:

[0069] The preparation method of blueberry extract specifically includes the following steps:

[0070] The oxidized coconut shell activated carbon loaded with hydrolytic enzyme in Preparation Example 8 was replaced with the oxidized coconut shell activated carbon loaded with hydrolytic enzyme obtained in Preparation Example 4, while the other preparation conditions remained the same as in Preparation Example 8.

[0071] Preparation Example 10:

[0072] The preparation method of blueberry extract specifically includes the following steps:

[0073] The oxidized coconut shell activated carbon loaded with hydrolytic enzyme in Preparation Example 8 was replaced with the oxidized coconut shell activated carbon loaded with hydrolytic enzyme obtained in Preparation Example 5, while the other preparation conditions remained the same as in Preparation Example 8.

[0074] Preparation Example 11:

[0075] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0076] One part by weight of eugenol and one part by weight of 3-buten-1-ol were added to 30 parts by weight of ethanol solution and stirred. Then, 0.009 parts by weight of ammonium persulfate were added and stirred until completely dispersed. The dispersed mixture was then placed in a water bath at 30°C and reacted for 60 minutes. After the reaction was completed, the mixture was immediately poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain hydroxyl-terminated modified eugenol prepolymer.

[0077] One part by weight of hydroxyl-terminated modified eugenol prepolymer and one part by weight of levodopa were added to 80 parts by weight of dichloromethane. Then, an esterification catalyst consisting of one part by weight of EDC hydrochloride, 0.7 parts by weight of 4-dimethylaminopyridine, and 0.8 parts by weight of triethylamine was added, and the mixture was stirred and dispersed in an ultrasonic disperser at 300W for 20 minutes. After dispersion, the mixture was placed at 25°C and reacted for 15 hours. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the esterified levodopa-prepolymer.

[0078] Two parts by weight of esterified L-DOPA prepolymer and one part by weight of the blueberry extract obtained in Preparation Example 6 were weighed and added to 100 parts by weight of Tris-hydrochloride buffer. The mixture was then placed in an ultrasonic disperser and dispersed at 400 W for 20 min. After dispersion, the mixture was placed in a 25°C environment and the reaction time was set for 24 h. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the blueberry extract inclusions.

[0079] Preparation Example 12:

[0080] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0081] One part by weight of eugenol and 1.5 parts by weight of 3-buten-1-ol were added to 30 parts by weight of ethanol solution and stirred. Then, 0.009 parts by weight of ammonium persulfate were added and stirred until completely dispersed. The dispersed mixture was then placed in a water bath at 35°C and reacted for 65 minutes. After the reaction was completed, the mixture was immediately poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain hydroxyl-terminated modified eugenol prepolymer.

[0082] One part by weight of hydroxyl-terminated modified eugenol prepolymer and 1.5 parts by weight of levodopa were added to 80 parts by weight of dichloromethane. Then, an esterification catalyst consisting of 1 part by weight of EDC hydrochloride, 0.7 parts by weight of 4-dimethylaminopyridine, and 0.8 parts by weight of triethylamine was added, and the mixture was stirred and dispersed in an ultrasonic disperser at 300W for 20 minutes. After dispersion, the mixture was placed at 25°C and reacted for 18 hours. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the esterified levodopa-prepolymer.

[0083] Two parts by weight of esterified L-DOPA prepolymer and one part by weight of the blueberry extract obtained in Preparation Example 7 were weighed and added to 100 parts by weight of Tris-hydrochloride buffer. The mixture was then placed in an ultrasonic disperser and dispersed at 400 W for 20 min. After dispersion, the mixture was placed in a 25°C environment and the reaction time was set for 28 h. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the blueberry extract inclusions.

[0084] Preparation Example 13:

[0085] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0086] One part by weight of eugenol and two parts by weight of 3-buten-1-ol were added to 30 parts by weight of ethanol solution and stirred. Then, 0.009 parts by weight of ammonium persulfate were added and stirred until completely dispersed. The dispersed mixture was then placed in a water bath at 40°C and reacted for 70 minutes. After the reaction was completed, the mixture was immediately poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain hydroxyl-terminated modified eugenol prepolymer.

[0087] One part by weight of hydroxyl-terminated modified eugenol prepolymer and two parts by weight of levodopa were added to 80 parts by weight of dichloromethane. Then, an esterification catalyst consisting of one part by weight of EDC hydrochloride, 0.7 parts by weight of 4-dimethylaminopyridine, and 0.8 parts by weight of triethylamine was added, and the mixture was stirred and dispersed in an ultrasonic disperser at 300W for 20 minutes. After dispersion, the mixture was placed at 25°C and reacted for 20 hours. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the esterified levodopa-prepolymer.

[0088] Two parts by weight of esterified L-DOPA prepolymer and one part by weight of the blueberry extract obtained in Preparation Example 8 were weighed and added to 100 parts by weight of Tris-hydrochloride buffer. The mixture was then placed in an ultrasonic disperser and dispersed at 400W for 20 minutes. After dispersion, the mixture was placed in a 25°C environment and the reaction was timed for 30 hours. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the blueberry extract inclusions.

[0089] Preparation Example 14:

[0090] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0091] The blueberry extract in Preparation Example 13 was replaced with the blueberry extract obtained in Preparation Example 9, and the remaining preparation conditions were kept the same as in Preparation Example 13.

[0092] Preparation Example 15:

[0093] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0094] The blueberry extract in Preparation Example 13 was replaced with the blueberry extract obtained in Preparation Example 10, and the remaining preparation conditions were kept the same as in Preparation Example 13.

[0095] Preparation Example 16:

[0096] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0097] The ammonium persulfate in Preparation Example 13 was increased to 0.12 parts by weight, the reaction time was extended from 70 min to 2 h, and the other preparation conditions remained the same as in Preparation Example 13.

[0098] Preparation Example 17:

[0099] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0100] In Preparation Example 13, 3-buten-1-ol was replaced with cis-3-hexen-1-ol, and the remaining preparation conditions were the same as in Preparation Example 13.

[0101] Preparation Example 18:

[0102] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0103] One part by weight of chitosan and two parts by weight of levodopa were added to 80 parts by weight of deionized water, and then the mixture was dispersed in an ultrasonic disperser at 300W for 20 minutes. After dispersion, the mixture was placed in a 25°C environment and the reaction time was set for 20 hours. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain a chitosan-crosslinked levodopa mixture.

[0104] Two parts by weight of the chitosan crosslinked L-DOPA mixture and one part by weight of the blueberry extract obtained in Preparation Example 8 were weighed and added to 100 parts by weight of Tris-hydrochloride buffer. The mixture was then placed in an ultrasonic disperser and dispersed at 400W for 20 minutes. After dispersion, the mixture was placed in a 25°C environment and the reaction was timed for 30 hours. After the reaction, gel solidification was observed, and the preparation failed.

[0105] This may be because although chitosan also has antibacterial properties and can form cross-links with L-DOPA through hydrogen bonds to encapsulate blueberry extract, chitosan itself contains many functional groups that form hydrogen bonds and cross-links. This makes it easy to form a dense three-dimensional network structure through cross-linking, which may lead to severe gelation, resulting in preparation failure and unusability. It can be seen that the selection of antibacterial monomers in the system of this invention has relatively strict requirements. If natural polymeric antibacterial materials are used, although antibacterial effect can be achieved, improper control of the ratio can easily lead to gel solidification, which is not conducive to use.

[0106] Preparation Example 19:

[0107] The preparation method of blueberry extract inclusions specifically includes the following steps:

[0108] One part by weight of 3-buten-1-ol and two parts by weight of levodopa were added to 80 parts by weight of dichloromethane. Then, an esterification catalyst consisting of one part by weight of EDC hydrochloride, 0.7 parts by weight of 4-dimethylaminopyridine, and 0.8 parts by weight of triethylamine was added, and the mixture was stirred and dispersed in an ultrasonic disperser at 300W for 20 minutes. After dispersion, the mixture was placed at 25°C and reacted for 20 hours. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the esterified levodopa prepolymer.

[0109] Two parts by weight of esterified L-DOPA prepolymer and one part by weight of the blueberry extract obtained in Preparation Example 8 were weighed and added to 100 parts by weight of Tris-hydrochloride buffer. The mixture was then placed in an ultrasonic disperser and dispersed at 400W for 20 minutes. After dispersion, the mixture was placed in a 25°C environment and the reaction was timed for 30 hours. Immediately after the reaction, the mixture was poured into a dialysis bag with a molecular weight cutoff of 500 Da and dialyzed with deionized water for 2 days to obtain the blueberry extract inclusions.

[0110] Example 1:

[0111] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0112] Weigh 14 parts by weight of the blueberry extract inclusion obtained in Preparation Example 11, 50 parts by weight of deionized water, 3 parts by weight of surfactant Tween-80 and 1 part by weight of co-surfactant ethanol, mix them and put them into a homogenizer, and then homogenize them at 9000 r / min for 2 min to obtain the fragrance composition.

[0113] Example 2:

[0114] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0115] Weigh 18 parts by weight of the blueberry extract inclusion obtained in Preparation Example 12, 55 parts by weight of deionized water, 3.5 parts by weight of surfactant Tween-80 and 1.5 parts by weight of co-surfactant ethanol, mix them and put them into a homogenizer, and then homogenize them at 10000 r / min for 3 min to obtain the fragrance composition.

[0116] Example 3:

[0117] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0118] 20 parts by weight of the blueberry extract inclusion obtained in Preparation Example 13, 60 parts by weight of deionized water, 4 parts by weight of surfactant Tween-80 and 2 parts by weight of co-surfactant ethanol were weighed and mixed in a homogenizer, and then homogenized at 10000 r / min for 4 min to obtain the fragrance composition.

[0119] Comparative Example 1:

[0120] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0121] 20 parts by weight of the blueberry extract inclusion obtained in Preparation Example 14, 60 parts by weight of deionized water, 4 parts by weight of surfactant Tween-80 and 2 parts by weight of co-surfactant ethanol were weighed and mixed in a homogenizer, and then homogenized at 10000 r / min for 4 min to obtain the fragrance composition.

[0122] Comparative Example 2:

[0123] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0124] 20 parts by weight of the blueberry extract inclusion obtained in Preparation Example 15, 60 parts by weight of deionized water, 4 parts by weight of surfactant Tween-80 and 2 parts by weight of co-surfactant ethanol were weighed and mixed in a homogenizer, and then homogenized at 10000 r / min for 4 min to obtain the fragrance composition.

[0125] Comparative Example 3:

[0126] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0127] 20 parts by weight of the blueberry extract inclusion obtained in Preparation Example 16, 60 parts by weight of deionized water, 4 parts by weight of surfactant Tween-80 and 2 parts by weight of co-surfactant ethanol were weighed and mixed in a homogenizer, and then homogenized at 10000 r / min for 4 min to obtain the fragrance composition.

[0128] Comparative Example 4:

[0129] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0130] 20 parts by weight of the blueberry extract inclusion obtained in Preparation Example 17, 60 parts by weight of deionized water, 4 parts by weight of surfactant Tween-80 and 2 parts by weight of co-surfactant ethanol were weighed and mixed in a homogenizer, and then homogenized at 10000 r / min for 4 min to obtain the fragrance composition.

[0131] Comparative Example 5:

[0132] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0133] 20 parts by weight of the blueberry extract inclusion obtained in Preparation Example 19, 60 parts by weight of deionized water, 4 parts by weight of surfactant Tween-80 and 2 parts by weight of co-surfactant ethanol were weighed and mixed in a homogenizer, and then homogenized at 10000 r / min for 4 min to obtain the fragrance composition.

[0134] Comparative Example 6:

[0135] A method for preparing a flavor composition based on blueberry extract, specifically comprising the following steps:

[0136] 20 parts by weight of the blueberry extract inclusion obtained in Preparation Example 13, 60 parts by weight of deionized water, 4 parts by weight of surfactant Tween-80 and 2 parts by weight of co-surfactant ethanol were weighed and mixed in a homogenizer, and then homogenized at 15000 r / min for 2 min to obtain the fragrance composition.

[0137] The fragrance compositions prepared in Examples 1-3 and Comparative Examples 1-6 were dropped onto the surface of a 5cm×2cm paper. Volunteers smelled the fragrance at 1h, 12h, 24h and 7 days, respectively. The fragrance intensity and lasting time were evaluated by scoring the fragrance from 0 to 10, which represents the fragrance intensity from none to the strongest. The results are shown in Table 1 below.

[0138] Table 1 Aroma Performance Test

[0139] Source of materials Score of 1 hour 12h score 24h score Day 7 score Example 1 8 8 7 3 Example 2 8 7 7 3 Example 3 6 6 5 4 Comparative Example 1 2 1 0 0 Comparative Example 2 3 2 0 0 Comparative Example 3 3 1 0 0 Comparative Example 4 3 0 0 0 Comparative Example 5 1 0 0 0 Comparative Example 6 8 3 0 0

[0140] The fragrance compositions prepared in Examples 1-3 and Comparative Examples 1-6 were applied to bacterial culture dishes using a sterile loop until the surface was completely covered. The bacterial solution concentration was then increased to 1×10⁻⁶. 8 The CFU / ml Staphylococcus aureus bacterial suspension was evenly spread on the bacterial culture dish, and then incubated upside down in a constant temperature incubator at 37℃ for 24h. The bacterial count was then measured and the inhibition rate was calculated (the bacterial culture medium without added flavoring was used as the blank group, and the blank group was sterilized by irradiation under ultraviolet light for 12h after 24h of incubation). The results are shown in Table 2 below.

[0141] Table 2 Antibacterial properties

[0142] Source of materials Antibacterial rate (%) Example 1 48.3 Example 2 52.6 Example 3 54.1 Comparative Example 1 53.4 Comparative Example 2 53.5 Comparative Example 3 53.1 Comparative Example 4 53.5 Comparative Example 5 6.3 Comparative Example 6 53.8 Blank group 61.4

[0143] The following conclusions can be drawn from the test results in Tables 1 and 2 above:

[0144] (1) As can be seen from Examples 1 to 3, the present invention mixes and stirs blueberry extract encapsulated with modified poly-L-DOPA, deionized water, surfactant and co-surfactant to form a fragrance composition, avoiding the defects caused by high-temperature extraction methods such as steam extraction. This results in a fragrance composition that not only has a longer-lasting fragrance effect, but also improves the antibacterial effect, which promotes the reduction of spoilage caused by microbial parasitism, thus facilitating storage.

[0145] (2) Comparative Example 1 shows that the aroma intensity of the prepared fragrance composition is low and its duration is short. This may be because in this system, increasing the amount of inorganic acid phosphoric acid and raising the pyrolysis temperature leads to a significant increase in the specific surface area of ​​the prepared oxidized coconut shell. The increased specific surface area allows for more adsorption sites to adsorb the alcohols, esters, and terpenes released after blueberry hydrolysis, thus weakening the original aroma intensity. Therefore, this invention imposes strict limitations on the specific surface area of ​​activated carbon. While an excessively large specific surface area is beneficial for the loading and fixation of hydrolytic enzymes, it also increases the adsorption of fragrance components, thereby weakening the aroma intensity and duration of the final prepared fragrance composition.

[0146] (3) Comparative Example 2 shows that the aroma intensity of the prepared fragrance composition is low and the duration is short. This may be because, although cellulase and xylanase both have the function of hydrolyzing plant cell walls, the hydrolysis conditions constructed in this system are not conducive to the enzymatic hydrolysis of cellulase, resulting in poor hydrolysis of blueberries. This may lead to less release of fragrance components such as alcohols, esters and terpenes, resulting in poor aroma intensity and longevity of the final fragrance composition.

[0147] (4) Comparative Example 3 shows that the aroma intensity of the prepared fragrance composition is low and the duration is short. This may be because the excessive amount of ammonium persulfate as a free radical initiator and the long initiation time in this system may lead to excessive carbon chain growth. Consequently, when esterified L-DOPA-prepolymer is prepared by grafting L-DOPA, the oxidative self-polymerization of L-DOPA in a weakly alkaline environment is greatly affected by the carbon chain due to the excessive carbon chain length, resulting in poor polymerization and crosslinking. This may lead to poor encapsulation of blueberry extract, resulting in poor aroma intensity and fragrance duration of the final prepared fragrance composition.

[0148] (5) Comparative Example 4 shows that the aroma intensity of the prepared fragrance composition is low and the duration is short. This may be because the carbon chain of cis-3-hexen-1-ol is longer than that of 3-buten-1-ol. During prepolymerization in this system, the carbon chain may grow too long. Consequently, when esterified L-DOPA-prepolymer is prepared by grafting L-DOPA, the oxidative self-polymerization of L-DOPA in a weakly alkaline environment is greatly affected by the carbon chain due to the excessive carbon chain length. The polymerization crosslinking is poor, which may result in poor encapsulation of blueberry extract, leading to poor aroma intensity and longevity of the final fragrance composition.

[0149] (6) Comparative Example 5 revealed that the prepared fragrance composition had a low aroma intensity, short duration, poor antibacterial effect, and short shelf life. This may be because although 3-buten-1-ol can affect the oxidative self-polymerization of L-DOPA through the carbon chain, the amount used in this system may have resulted in a weaker ability to weaken the oxidative self-polymerization of L-DOPA, potentially leading to overly dense cross-linking of the oxidative self-polymerization, which is not conducive to aroma release. Furthermore, due to the omission of eugenol, the aroma generated solely by the release of fragrance components such as alcohols, esters, and terpenes from blueberry extract in this system is weak, and the loss of antibacterial effect may lead to a short shelf life of the prepared fragrance composition, which is not conducive to practical use.

[0150] (7) Comparative Example 6 shows that the fragrance composition prepared has a poor fragrance retention time. This may be because, during homogenization, although increasing the rotation speed can shorten the homogenization time, excessively high rotation speed may significantly increase shearing, causing the inclusions to be subjected to multiple high-intensity shears in a short period of time, resulting in rupture and loss of sustained-release effect.

[0151] The embodiments described above provide a detailed explanation of the technical solutions and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Various changes and modifications can be made to the present invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed.

Claims

1. A flavor composition based on blueberry extract, characterized in that, The flavoring composition comprises the following raw materials in parts by weight: 14-20 parts by weight of blueberry extract inclusions, 50-60 parts by weight of deionized water, 3-4 parts by weight of surfactant and 1-2 parts by weight of co-surfactant; The method for preparing the blueberry extract inclusions includes the following steps: Antibacterial monomers, enol compounds, ammonium persulfate and ethanol solution were mixed and dispersed in a weight ratio of 1:1~2:0.009:30 and reacted at a temperature of 30℃~40℃ for 60min~70min to obtain hydroxyl-terminated modified eugenol prepolymer; Hydroxyl-terminated modified eugenol prepolymer, levodopa, dichloromethane and esterification catalyst were mixed and ultrasonically dispersed in a weight ratio of 1:1~2:80:2.5 and reacted at 25℃ for 15h~20h to obtain esterified levodopa-prepolymer; Esterified L-DOPA prepolymer, blueberry extract, and Tris-hydrochloride buffer were mixed and ultrasonically dispersed at a weight ratio of 2:1:100 and reacted at 25°C for 24-30 hours to obtain blueberry extract inclusions. The preparation method of the blueberry extract includes the following steps: Oxidized coconut shell activated carbon loaded with hydrolytic enzyme and blueberry pulp are mixed in a weight ratio of 1:80~100 to form a mixture. After adjusting the pH of the mixture to 4.5~5.0, it is hydrolyzed at 40℃~50℃ for 70min~80min to obtain a hydrolysate. The hydrolysate and the mixed extractant were mixed at a weight ratio of 1:1 and extracted at 30℃~40℃ for 2h~3h to obtain the extract phase. The extract phase was then subjected to vacuum distillation and freeze drying to obtain blueberry extract. The method for preparing the enzyme-loaded oxidized coconut shell activated carbon includes the following steps: Coconut shell powder, inorganic acid and purified water are mixed and impregnated in a weight ratio of 1:1~1.2:10~15 to obtain an impregnation solution. The impregnation solution is then pyrolyzed at 500℃~600℃ for 80min~90min to obtain coconut shell activated carbon. Activated coconut shell carbon and nitric acid solution are mixed at a weight ratio of 1:10~12 and oxidized for 4~5 hours to obtain oxidized coconut shell activated carbon; Oxidized coconut shell activated carbon, phosphate buffer, hydrolase, ethylenediamine, EDC hydrochloride and N-hydroxysuccinimide were mixed and dispersed in a weight ratio of 5:100:0.1~0.2:0.1:5.5:5.5 and reacted at 25℃ for 15h~18h to obtain oxidized coconut shell activated carbon loaded with hydrolase.

2. The flavor composition based on blueberry extract according to claim 1, characterized in that, The antibacterial monomer includes eugenol.

3. The flavor composition based on blueberry extract according to claim 1, characterized in that, The enol compounds include 3-buten-1-ol.

4. The flavor composition based on blueberry extract according to claim 1, characterized in that, The hydrolytic enzyme is xylanase.

5. The flavor composition based on blueberry extract according to claim 1, characterized in that, The surfactant includes Tween-80.

6. The flavor composition based on blueberry extract according to claim 1, characterized in that, The co-surfactant includes ethanol.

7. A method for preparing a flavor composition based on blueberry extract as described in any one of claims 1 to 6, characterized in that, The preparation method includes the following steps: The fragrance composition is obtained by mixing blueberry extract inclusions, deionized water, surfactant and co-surfactant and homogenizing at a speed of 9000~10000 r / min for 2~4 min.