Slow-release floral essence particles, and preparation method and application thereof

Abstract

The invention relates to the field of daily chemical products, and discloses a slow-release floral essence particle, a preparation method and application thereof, a stable nanocrystallization floral essence core is formed by adopting a high-pressure homogenization method, and a mesoporous silica shell layer is coated on the basis of the nanocrystallization floral essence core to form a nano essence particle with a slow-release function. The chemical stability of the raw materials is improved, and the slow-release effect of fragrance is achieved through a structure improvement method.

Description

Technical Field

[0001] The invention relates to the field of daily chemical products, and in particular to a slow-release floral fragrance particle, a preparation method and application thereof. Background Art

[0002] In the modern daily chemical and food industries, flavors are an important additive that enhances the aroma of products and improves consumers' sensory experience. Although chemically synthesized flavors are widely used due to their low cost and strong fragrance, they have limitations in simulating the complex aroma of natural essential oils. In addition, the use of chemical flavors may cause some health and safety issues, such as allergic reactions or adverse effects on human health after long-term use.

[0003] On the other hand, natural essential oils are favored for their unique aroma and multiple potential health benefits. They are extracted from plants and contain a variety of active ingredients that not only provide a rich aroma layer, but also have antibacterial and anti-inflammatory properties. However, natural essential oils face some challenges in industrial applications, such as stability issues in flavor formulations and possible aroma changes during storage and use.

[0004] To overcome these limitations, researchers and manufacturers are exploring new technologies and methods to enhance the stability and durability of natural essential oils while maintaining their natural aroma and health benefits. This includes developing new extraction and formulation techniques, as well as adopting advanced packaging and storage methods to protect the active ingredients of essential oils. Summary of the invention

[0005] Based on this, it is necessary to address the above technical problems. The present invention provides a sustained-release floral fragrance essence particle, a preparation method and its application. A stable nano-sized floral fragrance essence core is formed by a high-pressure homogenization method, and a mesoporous silica shell is coated on this basis to form nano-flavor particles with sustained-release function. This not only improves the chemical stability of the raw materials, but also achieves the effect of sustained-release fragrance through structural improvement.

[0006] The present invention discloses a slow-release floral fragrance particle, which at least comprises a nano-sized floral fragrance core and a mesoporous silica shell layer, wherein the mesoporous silica shell layer covers the nano-sized floral fragrance core to form a slow-release floral fragrance particle;

[0007] The nano-floral fragrance core uses a high-pressure homogenization method to refine the compound floral fragrance to 100-150nm;

[0008] The mesoporous silica shell layer is coated on the outer surface of the nano-sized floral essence core by a sol-gel method.

[0009] The nano-floral fragrance core is composed of a mixture of floral essential oil, floral fragrance aniseed, and floral fragrance base material in the weight proportions of (7-10%): (40-60%): (20-40%).

[0010] Furthermore, the floral essential oil comprises at least one of jasmine flower oil, white jasmine flower oil, lilac flower oil, rose flower oil, jasmine flower oil, spur flower absolute oil, and osmanthus flower oil, or a mixture of several thereof;

[0011] The floral essence aniseed comprises at least one of phenylethyl alcohol, linalool, methyl dihydrojasmonate, benzyl salicylate, linalyl acetate, and ionone, or a mixture of several thereof;

[0012] The floral fragrance base material comprises at least one of rose alcohol, nerol, raspberry ketone, ambergris ketone, lily of the valley aldehyde, cyperus aldehyde, alpha-amyl cinnamaldehyde, rose oxide, methyl cedarwood ether, solid fragrance crystal rose, galaxol, coumarin, and heliotropin, or a mixture of several of them.

[0013] Wherein, the thickness of the mesoporous silica shell layer is 20-50nm, and the mesopore size is 5-25nm.

[0014] The present invention also discloses a method for preparing sustained-release floral fragrance particles, which comprises at least the following steps:

[0015] S1, respectively prepare floral essential oil, floral essence aniseed, and floral essence base material, and mix them to obtain floral essence;

[0016] S2, dispersing the floral essence obtained in step S1 in a surfactant solution at a volume fraction of 1:5-10, and sending the evenly dispersed solution into a high-pressure homogenizer, adjusting the homogenization parameters, and obtaining a homogenized nano-floral essence core;

[0017] S3, adding a silicon source and a surface modifier to the nano-sized floral essence core obtained in step S2, adjusting the pH of the solution to a weakly alkaline state, stirring to promote hydrolysis of the silicon source, and generating a sol-gel reaction to generate floral essence particles having a core-shell structure;

[0018] S4. The floral fragrance particles with a core-shell structure obtained in step S3 are subjected to a solvent extraction method to elute the surfactant in the shell structure to form mesoporous channels, thereby obtaining slow-release floral fragrance particles.

[0019] Preferably, the "adjusting homogenization parameters" in step S2 at least includes:

[0020] Homogenization pressure setting: 180-200MPa;

[0021] Temperature setting: when the feed temperature is less than 50°C, turn on the high-pressure homogenizer for circulating cooling, and the homogenization process temperature is not higher than 75°C;

[0022] Flow rate setting: 200-500mL / min.

[0023] Preferably, the S3 step specifically includes:

[0024] S31, weighing a silicon source according to a volume fraction ratio of the nano-sized floral essence core to the silicon source of 1:1-10; weighing a surface modifier according to a volume fraction ratio of the nano-sized floral essence core to the surface modifier of 1:0.01-0.1; adding the silicon source and the surface modifier to the mixed solution prepared in S31, and adjusting the pH value of the solution to weak alkalinity, maintaining a constant temperature of 30-35°C, and stirring for hydrolysis for 2-4 hours;

[0025] S32. The mixture solution obtained in step S31 is dispensed into centrifuge tubes, and centrifuged at 10,000 rpm for 10 minutes to obtain floral essence particles having a core-shell structure.

[0026] Preferably, in the step S4, the specific conditions of "using solvent extraction to elute the surfactant in the shell structure of the floral fragrance particles with a core-shell structure obtained in step S3" are:

[0027] Disperse the core-shell structured floral essence particles in an organic solvent, stir and disperse in a water bath, with a stirring speed of 600-800 rpm, a water bath temperature of 30-40°C, and an elution time of 2-6 hours;

[0028] The organic solvent is: methanol, ethanol, or acidic methanol or ethanol solution.

[0029] The present invention also discloses an application of slow-release floral fragrance essence particles. The slow-release floral fragrance essence particles are the slow-release floral fragrance essence particles mentioned above and are applied to the production of floral fragrance essence.

[0030] By adopting the above technical solution, the present invention has the following beneficial effects:

[0031] 1. The nano-floral fragrance core prepared by high-pressure homogenization and the coating of the mesoporous silica shell layer in the present invention significantly improve the chemical stability of the fragrance particles and reduce the risk of aroma change and decomposition during storage and use. At the same time, since natural essential oils are mainly used as raw materials, the health and safety issues that may be caused by chemically synthesized fragrances are reduced, making the product safer and more environmentally friendly.

[0032] 2. The present application uses nano-processing to make the aroma components of essential oils more evenly dispersed, improve the uniformity and consistency of the aroma, and make the final product have a richer and more delicate aroma level. At the same time, the active ingredients contained in the natural essential oils can better retain their potential health benefits such as antibacterial and anti-inflammatory under the protection of nano-processing and mesoporous silica shells, increasing the added value of the product.

[0033] 3. The mesoporous silica shell design achieves a slow-release effect of the fragrance, allowing the fragrance particles to slowly release the fragrance over a certain period of time, thereby extending the persistence of the fragrance and improving the consumer experience. Although the cost of natural essential oils is relatively high, the application of nano-sizing and slow-release technology can reduce the amount of fragrance used and increase the overall value of the product, thereby improving product quality while also bringing economic benefits.

[0034] 4. The preparation method of the slow-release floral fragrance particles of the present application is simple and easy to mass produce, and the particles have uniform morphology and size, which is convenient for adding and uniformly dispersing in various daily chemical and food industry products. The use of the mesoporous silica shell reduces the demand for chemical additives that are harmful to the environment, and silica is a substance that is widely present in nature and has little impact on the environment, which meets the requirements of sustainable development. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to make the content of the present invention more clearly understood, the present invention is further described in detail below according to specific embodiments and in conjunction with the accompanying drawings, which are characterized in that

[0036] Figure 1 It is a schematic diagram of the preparation process of the present invention.

[0037] Figure 2 It is a schematic diagram of the high-pressure homogenization process of the present invention.

[0038] Figure 3 This is a diagram of the core particle size of the nano-floral fragrance prepared in Example 3 of the present invention.

[0039] Figure 4 This is a transmission electron micrograph of the sustained-release floral essence particles prepared in Example 3 of the present invention. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0041] Example 1

[0042] This embodiment discloses a sustained-release floral fragrance particle, which at least comprises a nano-sized floral fragrance core and a mesoporous silica shell layer, wherein the mesoporous silica shell layer covers the nano-sized floral fragrance core to form a sustained-release floral fragrance particle, such as Figure 1 As shown;

[0043] The nano-floral fragrance core uses a high-pressure homogenization method to refine the compound floral fragrance to 100-150nm;

[0044] The mesoporous silica shell layer is coated on the outer surface of the nano-sized floral essence core by a sol-gel method.

[0045] Wherein, the thickness of the mesoporous silica shell layer is 20-50nm, and the mesopore size is 5-25nm.

[0046] In terms of structural selection, this embodiment uses a high-pressure homogenization method to pre-obtain a stable nano-sized floral essence core, and by processing the liquid under a high-pressure environment, the sample is fully broken and evenly distributed using a strong pressure effect, thereby obtaining a smaller and more uniform sample, and the shear force is generated by a high-speed rotating rotor and stator, or a strong shear and impact effect is generated by a high-pressure fluid in a specially constructed working head, so that the material is dispersed into tiny particles and evenly mixed, thereby achieving the purpose of homogenization and emulsification.

[0047] By hydrolyzing and coating the silicon source in an alkaline environment, a mesoporous silica shell is formed on the outer surface of the nano-sized floral essence core. By adjusting the input amount of the silicon source, the thickness of the mesoporous silica shell can be controlled to ultimately control the overall particle size of the final product, the sustained-release floral essence particles, to be within the range of 150-200nm.

[0048] In order to prevent the essential oil molecules from diffusing too quickly or too slowly, the thickness of the mesoporous silica shell and the mesopore size parameters are further limited. Since the nanoparticles synthesized in this application do not need to excessively utilize the specific surface area and mesopore volume of mesoporous silica, no special limitation is imposed on the size of the mesopores.

[0049] Similarly, if the reaction conditions are modified, such as forming nanoparticles with larger particle sizes, or even moving away from nano-particles to form dispersed particles of micron or larger size, it can also be achieved by adopting a similar design or modified design of the present application. However, in order to consider improving the lasting fragrance of the essence and the utilization rate of expensive essential oils at a reasonable particle size, this embodiment believes that it is more appropriate to prepare the particle size within the range of 150-200nm. It is also believed that this type of preparation at the nanoscale is in line with the principle of economic efficiency.

[0050] The design of sustained-release floral fragrance particles is achieved through the careful selection and proportioning of various floral fragrance raw materials to achieve the richness, layering and persistence of the aroma.

[0051] Among them, floral essential oils, as the core component, are responsible for providing the main aroma characteristics of the fragrance and extending the fragrance duration, and are the soul of the entire fragrance formula. The type and proportion of essential oils selected directly affect the fragrance style and quality of the fragrance, so it is crucial to strictly screen the type and quality of essential oils.

[0052] As a basic component, floral base is used to set off and enhance the aroma intensity of floral essential oils, while also increasing the fragrance and layering of the fragrance by blending various aroma components. The selection of base needs to take into account its compatibility with essential oils and its contribution to the overall aroma to ensure the harmony, unity, richness and variety of the fragrance.

[0053] As an auxiliary component, aniseed is mainly used to dilute the concentration of floral essential oils, adjust the volatilization rate of the aroma, and make the fragrance more fresh and elegant. The selection and dosage of aniseed need to be precisely controlled to avoid covering the main aroma of the essential oil, while ensuring the natural dissemination and durability of the aroma.

[0054] Example 2

[0055] This embodiment discloses a method for preparing sustained-release floral essence particles based on the design of embodiment 1. The preparation method comprises the following steps:

[0056] S1. Prepare floral essential oil, floral essence aniseed, and floral essence base respectively, and mix them to obtain floral essence, wherein the floral essential oil, floral essence aniseed, and floral essence base are in the proportions of (7-10%), (40-60%), and (20-40%) by weight;

[0057] S2, dispersing the floral essence obtained in step S1 in a surfactant solution at a volume fraction of 1:5-10, and sending the evenly dispersed solution into a high-pressure homogenizer, adjusting the homogenization parameters, and obtaining a homogenized nano-floral essence core;

[0058] S3, adding a silicon source and a surface modifier to the nano-sized floral essence core obtained in step S2, adjusting the pH of the solution to a weakly alkaline state, stirring to promote hydrolysis of the silicon source, and generating a sol-gel reaction to generate floral essence particles having a core-shell structure;

[0059] S4. The floral fragrance particles with a core-shell structure obtained in step S3 are subjected to a solvent extraction method to elute the surfactant in the shell structure to form mesoporous channels, thereby obtaining slow-release floral fragrance particles.

[0060] The configuration and final mixing of the floral essential oil, floral essence aniseed, and floral essence base in step S1 at least include:

[0061] S11, adding jasmine flower oil, white jasmine oil, lilac flower oil, rose flower oil, jasmine flower oil, spur flower absolute oil, and osmanthus flower oil to the base oil in sequence, and mixing evenly to obtain a floral essential oil;

[0062] S12, add rose alcohol, nerol, raspberry ketone, ambergris ketone, lily of the valley aldehyde, cyperus aldehyde, alpha-amyl cinnamaldehyde, rose oxide, methyl cedarwood ether into a stirring pot in sequence, and start the stirrer to stir until completely mixed. Solid spices need to be dissolved with heated auxiliary materials and left to stand for use;

[0063] S13, add phenylethyl alcohol, linalool, methyl dihydrojasmonate, benzyl salicylate, linalyl acetate, and ionone to a stirring pot with a heating device in sequence, turn on the stirrer, and set the stirring pot temperature to 50-60°C and start heating and stirring; then add solid fragrance crystal rose, galaxol, coumarin, and jasminoids to the stirring pot in sequence, and continue stirring until the solid fragrance is completely dissolved. After the solid fragrance is completely dissolved, cool to room temperature and let stand for use;

[0064] S14, adding floral essential oil, floral base and floral aniseed into a stirring pot in sequence, stirring evenly, purifying and filtering to obtain a composite floral essence.

[0065] Wherein, the "adjusting homogenization parameters" in step S2 at least includes:

[0066] Homogenization pressure setting: 180-200MPa;

[0067] Temperature setting: when the feed temperature is less than 50°C, turn on the high-pressure homogenizer for circulating cooling, and the homogenization process temperature is not higher than 75°C;

[0068] Flow rate setting: 200-500mL / min.

[0069] The S3 step specifically includes:

[0070] S31, weighing a silicon source according to a volume fraction ratio of the nano-sized floral essence core to the silicon source of 1:1-10; weighing a surface modifier according to a volume fraction ratio of the nano-sized floral essence core to the surface modifier of 1:0.01-0.1; adding the silicon source and the surface modifier to the mixed solution prepared in S31, and adjusting the pH value of the solution to weak alkalinity, maintaining a constant temperature of 30-35°C, and stirring for hydrolysis for 2-4 hours;

[0071] S32. The mixture solution obtained in step S31 is dispensed into centrifuge tubes, and centrifuged at 10,000 rpm for 10 minutes to remove the supernatant, the excess surfactant solution and the nanoparticles that are not involved in the encapsulation and independently form silica spheres are removed to obtain floral fragrance particles with a core-shell structure.

[0072] Among them, the specific conditions of the step S4 of "using solvent extraction to elute the surfactant in the shell structure of the floral fragrance particles with a core-shell structure obtained in step S3" are:

[0073] Disperse the core-shell structured floral essence particles in an organic solvent, stir and disperse in a water bath, with a stirring speed of 600-800 rpm, a water bath temperature of 30-40°C, and an elution time of 2-6 hours;

[0074] The organic solvent is: methanol, ethanol, or acidic methanol or ethanol solution.

[0075] In practical applications, due to the variety of floral fragrances produced and different requirements for the retention time of fragrance, a variety of combinations can be selected when preparing compound floral fragrances. For example, for products that require long-lasting fragrance, you can choose essential oils with strong persistence, such as rose essential oil or jasmine essential oil, and appropriately increase the proportion of floral base materials to enhance the overall persistence of the fragrance. For products that pursue a fresh and elegant fragrance, you can choose citrus essential oils such as orange blossom oil or lemon oil, and adjust the proportion of aniseed to achieve a more refreshing aroma effect.

[0076] In addition, by adjusting the types and proportions of floral essential oils, aniseed and base materials, various floral fragrances can be created, such as sweet fruity floral fragrance, fresh green leaf floral fragrance or warm oriental floral fragrance, etc. This flexibility enables the slow-release floral fragrance particles of the present invention to be widely used in daily chemical products and the food industry to meet the specific requirements of different products for fragrance characteristics.

[0077] During the preparation process, the thickness and mesopore size of the mesoporous silica shell can be adjusted according to the desired sustained-release effect to control the release rate of aroma molecules in the flavor particles. For example, increasing the shell thickness or reducing the mesopore size can slow down the release of aroma molecules, thereby extending the persistence of the fragrance; conversely, reducing the shell thickness or increasing the mesopore size can speed up the release of the fragrance, which is suitable for application scenarios where the fragrance needs to be released quickly.

[0078] Example 3

[0079] This example uses the nanoparticle design ideas and synthesis preparation methods proposed in Examples 1 and 2 as guidance, and refines the selection and product characterization of the specific preparation method. The specific synthesis steps are not repeated here. The long-lasting fragrance essence particles with a strong rose fragrance selected in this example are required to have a fragrance retention time of more than 72 hours. Specifically:

[0080] The configuration and final mixing of the floral essential oil, floral essence aniseed, and floral essence base in step S1 are as follows:

[0081] The floral essential oil is selected in the following weight proportions: 0.5% euphorbia cerasifera oil, 0.5% lilac oil, 2.5% rose oil, and the balance is base oil, with a total weight proportion of 10%, wherein the base oil can be of natural origin, such as vegetable oil (e.g. olive oil, sweet almond oil, grape seed oil, etc.), or synthetic or refined oil, which is not limited here;

[0082] The floral fragrance base material is selected from the following weight percentages: 2% of rose alcohol, 4% of nerol, 5% of raspberry ketone, 5% of ambergris ketone, 5% of lily of the valley aldehyde, 6% of alpha-amyl cinnamaldehyde, and 5% of rose oxide, with a total weight percentage of 32%;

[0083] The floral essence aniseed is selected in the following weight proportions: 2.5% linalool, 6% benzyl salicylate, 2.5% linalyl acetate, with a total weight proportion of 58%, and phenylethyl alcohol is used as the remainder to fill the insufficient aniseed.

[0084] In step S2, the homogenization pressure is set to 180-200 MPa and the flow rate is set to no more than 500 mL / min. By increasing the homogenization pressure and controlling the flow rate of the solution, the size of the flavor particles after homogenization can be ensured to meet the requirements.

[0085] In step S3, the silicon source is weighed according to the volume fraction ratio of the nano-sized floral essence core to the silicon source of 1:1; the surface modifier is weighed according to the volume fraction ratio of the nano-sized floral essence core to the surface modifier of 1:0.05. In this process, excess silicon source and surface modifier are allowed. The silicon source exceeding the reaction requirement will form silicon balls and leave the target reaction by itself. The surface modifier exceeding the reaction requirement will also leave the target reaction by itself after the reaction with the silanol group on the surface of silica is completed.

[0086] Among them, Figure 2 As shown, in the process of preparing floral essence particles, since heat is generated during the high-pressure homogenization process, a temperature control system or a cooler is required to maintain the temperature of the material to avoid affecting the thermal sensitivity of the essential oil material, and the whole process is controlled below 75°C. The homogenization pressure needs to reach 180-200Mpa to control the particles at the nanometer scale, and the pressure and shear force affecting the homogenization process are further controlled by reducing the feed flow rate, thereby affecting the homogenization effect, such as Figure 3 As shown, the size of the prepared nano-floral fragrance core was characterized by dynamic light scattering, and it was found that the size of the nano-floral fragrance core was about 148nm. Figure 4 As shown, the core-shell structured nanoparticles prepared by transmission electron microscopy showed that the core diameter was about 114.7 nm and the shell thickness was about 28.2 nm, which was similar to that obtained by dynamic light scattering test. The size of the prepared core-shell nanoparticles was relatively uniform.

[0087] Furthermore, the surfactant used in step S2 can be a long-chain alkyl surfactant, such as hexadecyltrimethylammonium bromide (CTAB), octadecyldimethylhydroxyethylammonium nitrate (DTAB), etc., and the surfactant concentration is about 0.1-0.2M. The addition of surfactant during high-pressure homogenization can help stabilize the nanoparticles and prevent them from aggregating together through physical or chemical forces. In step S3, the surfactant on the surface of the floral essence particles is used as a template to guide the subsequent silicon source for encapsulation; the silicon source can be tetraethoxysilane (TEOS), methyl orthosilicate (TMOS), etc., and the pH is adjusted and hydrolyzed by ammonia water.

[0088] Furthermore, because the silanol (Si-OH) on the surface of mesoporous silica is not water-soluble in itself, the silanol is polar, but they can interact with water molecules by forming hydrogen bonds. This interaction makes mesoporous silica show a certain hydrophilicity in an aqueous environment. In order to improve the water solubility of mesoporous silica, it is usually necessary to chemically modify the silanol to introduce more hydrophilic functional groups. For example, the surface can be modified by a silane coupling agent so that an organic-inorganic composite layer is formed on the surface of the nano-silica particles, thereby improving its dispersibility and stability in aqueous media. If it is necessary to improve the oil solubility of the material, other types of modifiers are usually selected, such as long-chain fatty acids or hydrophobic silane coupling agents.

[0089] Example 4

[0090] Based on Examples 1 and 2, this embodiment proposes applying the synthesized sustained-release floral fragrance essence particles to the production of floral fragrance essence. In actual production applications, different nano-sized floral fragrance essence cores can be prepared according to the desired aroma, flavor, fragrance retention time, etc., or only some essential oils that are relatively expensive or have special effects, such as hypnotic, tranquilizing, and soothing effects, can be used to prepare nano-sized floral fragrance essence cores. Other components are configured according to the original configuration process to finally form the desired synthesized and formulated fragrance.

[0091] The sustained-release floral fragrance particles can be used as additives, flavoring agents and other materials and mixed with various types of oily or aqueous solvents and solutions, which also improves the use scenarios of the sustained-release floral fragrance particles.

[0092] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A sustained-release floral fragrance particle, characterized in that: At least comprising a nano-sized floral essence core and a mesoporous silica shell layer, wherein the mesoporous silica shell layer covers the nano-sized floral essence core to form a slow-release floral essence particle; The nano-floral fragrance core uses a high-pressure homogenization method to refine the compound floral fragrance to 100-150nm; The mesoporous silica shell layer is coated on the outer surface of the nano-sized floral essence core by a sol-gel method.

2. The sustained-release floral fragrance particle according to claim 1, characterized in that: The nanometer floral essence core is composed of a mixture of floral essential oil, floral essence aniseed and floral essence base material in the weight proportions of (7-10%): (40-60%): (20-40%).

3. The sustained-release floral fragrance particle according to claim 2, characterized in that: The floral essential oil comprises at least one of jasmine flower oil, white jasmine flower oil, lilac flower oil, rose flower oil, jasmine flower oil, spur flower absolute oil and osmanthus flower oil, or a mixture of several of them; The floral essence aniseed comprises at least one of phenylethyl alcohol, linalool, methyl dihydrojasmonate, benzyl salicylate, linalyl acetate, and ionone, or a mixture of several thereof; The floral fragrance base material comprises at least one of rose alcohol, nerol, raspberry ketone, ambergris ketone, lily of the valley aldehyde, cyperus aldehyde, alpha-amyl cinnamaldehyde, rose oxide, methyl cedarwood ether, solid fragrance crystal rose, galaxol, coumarin, and heliotropin, or a mixture of several of them.

4. The sustained-release floral fragrance particle according to claim 1, characterized in that: The thickness of the mesoporous silica shell layer is 20-50 nm, and the size of the mesopores is 5-25 nm.

5. A method for preparing sustained-release floral fragrance particles according to any one of claims 1 to 4, characterized in that: The preparation method comprises at least the following steps: S1, respectively prepare floral essential oil, floral essence aniseed, and floral essence base material, and mix them to obtain floral essence; S2, dispersing the floral essence obtained in step S1 in a surfactant solution at a volume fraction of 1:5-10, and sending the evenly dispersed solution into a high-pressure homogenizer, adjusting the homogenization parameters, and obtaining a homogenized nano-floral essence core; S3, adding a silicon source and a surface modifier to the nano-sized floral essence core obtained in step S2, adjusting the pH of the solution to a weakly alkaline state, stirring to promote hydrolysis of the silicon source, and generating a sol-gel reaction to generate floral essence particles having a core-shell structure; S4. The floral fragrance particles with a core-shell structure obtained in step S3 are subjected to a solvent extraction method to elute the surfactant in the shell structure to form mesoporous channels, thereby obtaining slow-release floral fragrance particles.

6. The method for preparing sustained-release floral fragrance particles according to claim 5, characterized in that: The "adjusting homogenization parameters" in step S2 at least includes: Homogenization pressure setting: 180-200MPa; Temperature setting: when the feed temperature is less than 50°C, turn on the high-pressure homogenizer for circulating cooling, and the homogenization process temperature is not higher than 75°C; Flow rate setting: 200-500mL / min.

7. The method for preparing sustained-release floral fragrance particles according to claim 5, characterized in that: The S3 step specifically includes: S31, weighing a silicon source according to a volume fraction ratio of the nano-sized floral essence core to the silicon source of 1:1-10; weighing a surface modifier according to a volume fraction ratio of the nano-sized floral essence core to the surface modifier of 1:0.01-0.1; adding the silicon source and the surface modifier to the mixed solution prepared in S31, and adjusting the pH value of the solution to weak alkalinity, maintaining a constant temperature of 30-35°C, and stirring for hydrolysis for 2-4 hours; S32. The mixture solution obtained in step S31 is dispensed into centrifuge tubes, and centrifuged at 10,000 rpm for 10 minutes to obtain floral essence particles having a core-shell structure.

8. The method for preparing sustained-release floral fragrance particles according to claim 7, characterized in that: In the step S4, the specific conditions for "using solvent extraction to elute the surfactant in the shell structure of the floral fragrance particles with a core-shell structure obtained in step S3" are: Disperse the core-shell structured floral essence particles in an organic solvent, stir and disperse in a water bath, with a stirring speed of 600-800 rpm, a water bath temperature of 30-40°C, and an elution time of 2-6 hours; The organic solvent is: methanol, ethanol, or acidic methanol or ethanol solution.

9. An application of sustained-release floral fragrance particles, characterized in that: The sustained-release floral fragrance particle is a sustained-release floral fragrance particle as described in any one of claims 1 to 4, and is used in the production of floral fragrance.

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