Sustained-release capsule loaded with water-soluble aroma substances and preparation method of sustained-release capsule

Abstract

The invention relates to a sustained-release capsule loaded with a water-soluble aroma substance and a preparation method of the sustained-release capsule. The sustained-release capsule loaded with the water-soluble aroma substances comprises a core and a capsule wall material wrapping the core, the core comprises sustained-release cream, the sustained-release cream comprises an oil phase and a water phase, and the oil phase wraps the water phase; the water phase comprises a solution containing a water-soluble aroma substance and a water-soluble cationic polymer, the oil phase comprises silicon dioxide, wax, a gel and base oil, and the addition amount of the gel is 2-7 wt% on the basis of the mass of the base oil. Compared with a traditional water-in-oil emulsion, the sustained-release cream constructed by the invention has smaller molecular gaps, and can better realize sustained release of water-soluble substances. Meanwhile, the capsule is constructed, the release path of the water-soluble substances is prolonged through wrapping of the capsule wall material, diffusion of the water-soluble substances is inhibited through adsorption of the capsule wall material, and the slow release performance is improved; and in shape, subpackaging and additive amount control are facilitated, and commercialized application is facilitated.

Description

Technical Field

[0001] This application relates to the field of capsule technology, and in particular to a sustained-release capsule loaded with water-soluble aroma substances and a method for preparing the same. Background Technology

[0002] With the widespread application of water-soluble substance sustained-release technology in food and daily chemical product development, water-in-oil (W / O) emulsion systems have attracted attention due to their ability to encapsulate water-soluble active ingredients. Traditional processes form an emulsion structure by encapsulating dispersed aqueous droplets in a hydrophobic oil phase, achieving initial sustained release through the molecular barrier effect of the oil phase. However, existing technologies have limitations: First, the intermolecular forces in the liquid oil phase are weak and the network is not dense enough to effectively block the diffusion and volatilization of water-soluble small molecules, resulting in a sustained-release period of only 4-5 days, making sustained release difficult to achieve. Second, the physical barrier effect of the oil phase alone cannot control the release rate; encapsulation is required to add multiple layers of barriers, and existing encapsulation processes are relatively complex. Third, water-in-oil emulsion systems suffer from poor stability and limited application scenarios, hindering their industrial application. Therefore, further optimization of material design and preparation processes is urgently needed to suppress the rapid volatilization of water-soluble substances and achieve sustained release. Summary of the Invention

[0003] Based on this, this application provides a sustained-release capsule loaded with water-soluble aroma substances that can prevent the rapid volatilization of water-soluble substances and further provide better sustained-release performance, as well as a method for preparing the same.

[0004] The specific technical solution is as follows:

[0005] The first aspect of this application provides a sustained-release capsule loaded with a water-soluble aroma substance, comprising a core and a capsule wall material encapsulating the core, the core comprising a sustained-release cream, the sustained-release cream comprising an oil phase and an aqueous phase, the oil phase encapsulating the aqueous phase;

[0006] The aqueous phase comprises a solution containing water-soluble aroma substances and a water-soluble cationic polymer, and the oil phase comprises silica, wax, gelling agent and base oil. The amount of gelling agent added is 2 wt% to 7 wt% based on the mass of the base oil.

[0007] The sustained-release capsules loaded with water-soluble aroma substances described in this application include a core and a capsule wall material encapsulating the core. The core comprises a sustained-release cream, which includes a specific oil phase and a specific aqueous phase. In the sustained-release cream, an oil / water interface network is formed by the electrostatic adsorption between silica and cationic polymers, stabilizing the two-phase interface. The wax and gelling agent contained in the oil phase give it thermal melting properties; after cooling and solidification, it forms a three-dimensional network that not only stably encapsulates dispersed micro-aqueous droplets but also prevents rapid diffusion of the aqueous phase, achieving sustained release of water-soluble substances. Compared to traditional liquid emulsion gels, the constructed sustained-release cream has smaller molecular gaps, better achieving sustained release of water-soluble substances. Furthermore, constructing it into capsules, the encapsulation by the capsule wall material not only prolongs the release path of the water-soluble substances but also inhibits their diffusion through adsorption, improving sustained-release performance. In terms of shape, it facilitates commercial packaging and application. The sustained-release capsules of this application can achieve sustained release of various water-soluble substances and can be widely used in daily chemical and other fields, forming a new market product.

[0008] In some embodiments, the sustained-release cream satisfies at least one of the following characteristics:

[0009] (1) Based on the volume of the aqueous phase, the amount of water-soluble cationic polymer added is 5 mg / mL to 10 mg / mL;

[0010] (2) Based on the volume of the base oil, the amount of silica added is 15 mg / mL to 30 mg / mL;

[0011] (3) Based on the volume of the base oil, the amount of wax added is 5 (v / v)%~20 (v / v)%%;

[0012] (4) The particle size of the silica is 10 nm to 20 nm;

[0013] (5) The gelling agent includes Estogel;

[0014] (6) The base oil includes one or more of caprylic / capric triglycerides and silk oil;

[0015] (7) The wax includes one or more of paraffin wax, beeswax, soybean wax and coconut wax.

[0016] In some embodiments, the aqueous phase satisfies at least one of the following characteristics:

[0017] (1) The water-soluble cationic polymer includes one or more of polyoxyethylene diamine, chitosan and polyethyleneimine;

[0018] (2) The solution containing water-soluble aroma substances includes one or more of honeysuckle extract, coffee liquid, cocoa extract and wine liquid.

[0019] In some embodiments, the sustained-release cream comprises an oil phase and an aqueous phase in a volume ratio of 1:(0.6~2.5).

[0020] In some embodiments, the capsule wall material comprises a hydrophilic material, which includes one or more of gelatin, alginate, carrageenan, and gum arabic.

[0021] In some embodiments, the sustained-release capsules have a particle size of 2 mm to 4 mm.

[0022] A second aspect of this application also provides a method for preparing a sustained-release capsule, comprising the following steps:

[0023] A solution containing water-soluble aroma substances is mixed with a cationic polymer to obtain an aqueous phase;

[0024] Silica particles, wax, gelling agent and base oil are mixed to obtain the oil phase;

[0025] The aqueous phase and the oil phase are mixed and emulsified, and then cooled to prepare a sustained-release cream.

[0026] The sustained-release cream is encapsulated with capsule wall material to prepare a sustained-release capsule.

[0027] In some embodiments, the volume ratio of the oil phase to the water phase is 1:(0.6~2.5).

[0028] And / or, the rotation speed of the emulsification process is 18 kr / min to 20 kr / min, and the emulsification time is 3 min to 8 min.

[0029] In some embodiments, the step of encapsulating the sustained-release cream with the capsule wall material is performed using microfluidics, with the capsule wall material serving as the continuous phase and the sustained-release cream serving as the dispersed phase;

[0030] And / or, prior to the step of encapsulating the sustained-release cream with the capsule wall material, the method further includes:

[0031] The sustained-release cream was preheated and stirred at 70℃~80℃ and 100 r / min~200 r / min.

[0032] The capsule wall material was preheated and stirred at 50℃~60℃ and 100 r / min~200 r / min.

[0033] In some embodiments, during the preparation of sustained-release capsules using microfluidic technology, the flow rate ratio of the sustained-release cream to the capsule wall material is 1:(1~2). Attached Figure Description

[0034] Figure 1 This is a schematic diagram illustrating the principle of a sustained-release capsule prepared according to an embodiment of this application;

[0035] Figure 2 The images show the sustained-release cream and sustained-release capsules of Comparative Example 2 and Example 1 of this application.

[0036] Figure 3 Thermogravimetric analysis (TGA) charts of honeysuckle sustained-release cream and sustained-release capsules from Comparative Example 2 and Example 1 of this application are shown. Detailed Implementation

[0037] To facilitate understanding of this application, a more complete description is provided below, along with preferred embodiments. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0038] The implementation of this application will be described in detail below with reference to some implementation methods and embodiments. This embodiment is implemented based on the technical solution of this application, and provides detailed implementation methods and specific operation processes, but the protection scope of this application is not limited to the following embodiments.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0040] Unless otherwise stated or in case of contradiction, the terms or phrases used herein shall have the following meanings:

[0041] In this application, the terms "multiple" or "various" are used unless otherwise specified, referring to a quantity greater than or equal to 2. For example, "one or more" means one or more types.

[0042] In this application, terms such as "further" and "especially" are used to describe purposes and indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0043] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0044] In this application, when numerical intervals (i.e., numerical ranges) are mentioned, unless otherwise specified, the distribution of selectable numerical values ​​within the numerical interval is considered continuous, and includes the two endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that numerical interval, including the two endpoint integers of the numerical range, as well as every integer between the two endpoints, is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed herein should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. The term "numerical interval" can be broadly included to include numerical interval types such as percentage intervals, ratio intervals, and proportion intervals.

[0045] In this application, unless otherwise specified, the temperature parameters are permitted to be either constant temperature treatment or variations within a certain temperature range. It should be understood that the constant temperature treatment allows temperature fluctuations within the precision range controlled by the instrument. Fluctuations are permitted within ranges such as ±5℃, ±4℃, ±3℃, ±2℃, and ±1℃.

[0046] In this application, if the unit of a data range is only followed by the right endpoint, it indicates that the units of the left and right endpoints are the same. For example, 2-5 h means that the units of the left endpoint "2" and the right endpoint "5" are both h (hours).

[0047] One embodiment of this application provides a sustained-release capsule loaded with a water-soluble aroma substance, comprising a core and a capsule wall material encapsulating the core. The core comprises a sustained-release cream, which comprises an oil phase and an aqueous phase, with the oil phase encapsulating the aqueous phase. The aqueous phase comprises a solution containing the water-soluble aroma substance and a water-soluble cationic polymer. The oil phase comprises silica, wax, a gelling agent, and a base oil. Based on the mass of the base oil, the amount of gelling agent added is 2 wt% to 7 wt%.

[0048] The sustained-release capsules loaded with water-soluble aroma substances described in this application include a core and a capsule wall material encapsulating the core. The core comprises a sustained-release cream, which includes a specific oil phase and a specific aqueous phase. In the sustained-release cream, an oil / water interface network is formed by the electrostatic adsorption between silica and cationic polymers, stabilizing the two-phase interface. The wax and gelling agent contained in the oil phase give it thermal melting properties; after cooling and solidification, it forms a three-dimensional network that not only stably encapsulates dispersed micro-aqueous droplets but also prevents rapid diffusion of the aqueous phase, achieving sustained release of water-soluble substances. Compared to traditional liquid emulsion gels, the constructed sustained-release cream has smaller molecular gaps, better achieving sustained release of water-soluble substances. Furthermore, constructing it into capsules, the encapsulation by the capsule wall material not only prolongs the release path of the water-soluble substances but also inhibits their diffusion through adsorption, improving sustained-release performance. In terms of shape, it facilitates commercial packaging and application. The sustained-release capsules of this application can achieve sustained release of various water-soluble substances and can be widely used in daily chemical and other fields, forming a new market product.

[0049] It should be noted that the range of the amount of gelling agent added is "2 wt% to 7 wt%", which means the minimum and maximum value of the range of 2 wt% to 7 wt%, as well as every value between the minimum and maximum value. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, or 7 wt%; or any range of any two of these values, for example, including: 2 wt% to 5 wt%.

[0050] It is understandable that controlling the addition range of the above-mentioned gelling agent can make the sustained-release cream more stable and the sustained-release effect better. If too little gelling agent is added, an oleogel network cannot be formed. Although too much gelling agent can also form an oleogel network, it will cause the solidification point of the sustained-release cream to be too high, which will easily solidify and cause blockage during the microfluidic preparation stage, making it difficult to encapsulate.

[0051] In some embodiments, the amount of the water-soluble cationic polymer added is 5 mg / mL to 10 mg / mL, based on the volume of the aqueous phase.

[0052] The dosage of the water-soluble cationic polymer ranges from 5 mg / mL to 10 mg / mL, specifically the minimum and maximum values ​​within this range, as well as every value between these values. Specific examples include, but are not limited to, the point values ​​in the examples and the following point values: 5 mg / mL, 6 mg / mL, 7 mg / mL, 8 mg / mL, 9 mg / mL, or 10 mg / mL; or any range consisting of any two of these values, for example, including 5 mg / mL to 8 mg / mL.

[0053] In some embodiments, the amount of silica added is 15 mg / mL to 30 mg / mL, based on the volume of the base oil.

[0054] The amount of silica added is in the range of "15 mg / mL to 30 mg / mL", which means the minimum and maximum values ​​of the range of 15 mg / mL to 30 mg / mL, as well as every value between the minimum and maximum values. Specific examples include, but are not limited to, the point values ​​in the examples and the following point values: 15 mg / mL, 16 mg / mL, 17 mg / mL, 18 mg / mL, 19 mg / mL, 20 mg / mL, 21 mg / mL, 22 mg / mL, 23 mg / mL, 24 mg / mL, 25 mg / mL, 26 mg / mL, 27 mg / mL, 28 mg / mL, 29 mg / mL, or 30 mg / mL; or any range of any two of these values, for example, including: 15 mg / mL to 25 mg / mL.

[0055] In some embodiments, the amount of wax added is 5 (v / v)% to 20 (v / v)% based on the volume of the base oil.

[0056] The wax addition amount ranges from 5% to 20% (v / v), specifically the minimum and maximum values ​​within this range, as well as every value between these values. Specific examples include, but are not limited to, the point values ​​in the embodiments and the following point values: 5% (v / v)%, 6% (v / v)%, 7% (v / v)%, 8% (v / v)%, 9% (v / v)%, 10% (v / v)%, 11% (v / v)%, 12% (v / v)%, 13% (v / v)%, 14% (v / v)%, 15% (v / v)%, 16% (v / v)%, 17% (v / v)%, 18% (v / v)%, 19% (v / v)%, or 20% (v / v)%; or a range consisting of any two of these values. For example, this includes 10% (v / v)% to 20% (v / v)%.

[0057] Understandably, wax can raise the freezing point, allowing the sustained-release cream to remain solid at temperatures below 55°C.

[0058] In some embodiments, the particle size of the silica is 10 nm to 20 nm.

[0059] Understandably, nanoparticles can be more evenly dispersed in base oils, avoiding agglomeration and ensuring a uniform texture in the cream.

[0060] Optionally, the above-mentioned gelling agent includes Estogel.

[0061] In some embodiments, the Estogel described above is a compound of castor oil and IPDI copolymer, caprylic / capric triglyceride, and other components.

[0062] Understandably, the aforementioned gelling agent can promote the formation of a stable emulsion system between the aqueous and oil phases, stabilize the aqueous microdroplets, and prevent water-oil separation caused by microdroplet aggregation.

[0063] In some embodiments, the base oil includes one or more of caprylic / capric triglycerides and silk oil.

[0064] In some embodiments, the wax includes one or more of paraffin wax, beeswax, soy wax, and coconut wax.

[0065] In some embodiments, the water-soluble cationic polymers described above include one or more of polyoxyethylene diamine, chitosan, and polyethyleneimine.

[0066] The aforementioned cationic polymer can form a water / oil interface network through charge interaction with silica, stabilizing aqueous microdroplets and preventing water-oil separation caused by microdroplet aggregation.

[0067] In some embodiments, the solution containing water-soluble aroma substances includes one or more of honeysuckle extract, coffee liquid, cocoa extract, and alcoholic beverage.

[0068] In some embodiments, the sustained-release cream comprises an oil phase and an aqueous phase in a volume ratio of 1:(0.6~2.5).

[0069] In some embodiments, the capsule wall material includes a hydrophilic material, which includes one or more of gelatin, alginate, carrageenan, and gum arabic.

[0070] Understandably, the hydrophilic capsule wall material can effectively encapsulate the sustained-release cream, forming a stable capsule structure and prolonging the release pathway of water-soluble substances in the sustained-release cream. At the same time, the hydrophilic capsule wall material has an adsorption effect on esters, acids, alcohols, aldehydes, ketones and other components in water-soluble substances, inhibiting the diffusion of water-soluble substances, reducing permeation diffusion, and further improving the sustained-release performance.

[0071] In some embodiments, the hydrophilic material also includes glycerol.

[0072] Understandably, humectants such as glycerin can be added to the capsule wall material to improve sustained-release performance.

[0073] In some embodiments, based on the mass of the capsule wall material, the gelatin content is 5 wt% to 20 wt%, and the glycerin content is 0 to 10 wt%.

[0074] In some of these embodiments, the particle size of the sustained-release capsules is 2 mm to 4 mm.

[0075] Another embodiment of this application provides a method for preparing a sustained-release capsule loaded with a water-soluble aroma substance, including steps S100 to S400.

[0076] Step S100: Mix the solution containing water-soluble aroma substances with the cationic polymer to obtain an aqueous phase.

[0077] Step S200: Mix silica particles, wax, gelling agent and base oil to obtain the oil phase.

[0078] Step S300: Mix and emulsify the above aqueous phase and the above oil phase, and then cool to prepare a sustained-release cream.

[0079] Step S400: Encapsulate the above-mentioned sustained-release cream with the capsule wall material to prepare a sustained-release capsule.

[0080] The aforementioned water-in-oil sustained-release cream incorporates a dual stabilizing mechanism: an interfacial network and an oleogel network, such as... Figure 1 As shown, the silica particles in the oil phase have a large number of silanol groups on their surface, which easily dissociate and become negatively charged. Due to their hydrophobicity, they are distributed at the interface of the aqueous microdroplets and interact electrostatically with polyoxyethylene diamine molecules in the aqueous phase, which contain protonable cationic groups carrying a positive charge. This interaction forms an interfacial network that stabilizes the oil / water interface of the emulsion and effectively disperses the aqueous droplets. Subsequently, the hot-molten oil phase in the emulsion forms a stable oleogel network upon cooling due to the "wax-gelling agent" effect. This network contains multiple interactions, including between wax crystals, between gelling agent molecules, and between wax and gelling agent molecules, further stabilizing the internal micro-aqueous droplets and achieving sustained release. The aforementioned sustained-release capsules are prepared by encapsulating solid sustained-release cream into capsules using microfluidic technology. The capsule shell is constructed of a hydrophilic material that can adsorb alcohols, esters, acids, and phenols in the sustained-release substance, further extending the release period and achieving the desired sustained-release effect.

[0081] In some embodiments, the volume ratio of the oil phase to the water phase is 1:(0.6~2.5).

[0082] In some embodiments, the rotation speed of the emulsification process is 18 kr / min to 20 kr / min, and the emulsification time is 3 min to 8 min.

[0083] In some embodiments, the step of encapsulating the sustained-release cream with the capsule wall material is performed using microfluidic technology, with the capsule wall material serving as the continuous phase and the sustained-release cream serving as the dispersed phase.

[0084] In some embodiments, the step of encapsulating the sustained-release cream with the capsule wall material includes, prior to:

[0085] The above-mentioned sustained-release cream was preheated and stirred at 70℃~80℃ and 100 r / min~200 r / min.

[0086] The capsule wall material was preheated and stirred at 50℃~60℃ and 100 r / min~200 r / min.

[0087] In some embodiments, during the process of preparing sustained-release capsules using microfluidic technology, the flow ratio of the sustained-release cream to the capsule wall material is 1:(1~2).

[0088] The above-mentioned method for preparing sustained-release capsules loaded with water-soluble aroma substances is not only relatively simple in process, but also achieves sustained release over a long period of time. Furthermore, the sustained-release capsule preparation strategy of this application is applicable to all water-soluble substances, demonstrating strong versatility; by constructing them into capsules, the encapsulation of the capsule wall material prolongs the release pathway of the water-soluble substances, thereby improving the sustained-release performance. The sustained-release capsules of this application can achieve sustained release of various water-soluble substances and can be widely used in daily chemical and other fields, forming new market products.

[0089] In the daily chemical industry, for fragrance products such as perfumes and body lotions, slow-release capsules loaded with flavor substances from honeysuckle extract, coffee liquid, or wine, or other natural fragrances, can achieve long-lasting aroma release, making the fragrance more elegant and persistent, and reducing the frequency of reapplication. In the tobacco industry, especially in cigars, capsules are used in the aging process to slowly release aroma, effectively enhancing the richness and characteristic flavor of cigars. In agriculture, the active ingredients of water-soluble pesticides and fertilizers can be formulated into slow-release capsules for application to soil or plant surfaces. The capsules gradually release nutrients or pesticides according to environmental conditions such as humidity and temperature, reducing loss due to rainwater runoff, improving utilization efficiency, and reducing the risk of pesticide residues and environmental pollution.

[0090] To make the objectives, technical solutions, and advantages of this application clearer and more concise, the following specific embodiments are used for illustration, but this application is by no means limited to these embodiments. The embodiments described below are merely preferred embodiments of this application and can be used to describe this application, but should not be construed as limiting the scope of this application. It should be noted that any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

[0091] To better illustrate this application, the following description, in conjunction with embodiments, further explains the content of this application.

[0092] Example 1

[0093] I. Preparation of sustained-release cream

[0094] (1) Preparation of oil phase solution:

[0095] Preparation of GTCC-Estogel solution: Add 3.5 wt% Estogel (gelling agent, purchased from DKSH Chemical International Trading Co., Ltd., model: Estogel M) to the base oil GTCC oil (caprylic / capric triglyceride). Heat in an oil bath at 90°C and stir at 400 r / min to swell; after approximately 20-30 min, the Estogel will be completely swollen. Immediately afterwards, homogenize using a homogenizer at 20 kr / min for 30 min to disperse the Estogel molecules, obtaining the solution. Afterwards, maintain the oil bath temperature at 90°C to prevent the solution from cooling and solidifying.

[0096] Take 20 mL of GTCC-Estogel solution and add 2.5 mL of beeswax (12.5 vol%); the beeswax should be melted and liquefied at approximately 70°C before addition. Next, add 400 mg of SiO2 particles (concentration 20 mg / mL) and dissolve them, ensuring the solution is completely dissolved and clear. Throughout the preparation process, the solution is kept heated in an oil bath at 90-100°C with constant stirring to ensure complete dissolution of all substances.

[0097] (2) Preparation of aqueous solution: Take 20 mL of a solution containing 1 vol% water-soluble honeysuckle fragrance (purchased from Wenyuan Fragrance Co., Ltd.), add 100 mg polyoxyethylene diamine (5 mg / mL) and 1000 μL glycerol (5 vol%) respectively, and stir until fully dissolved.

[0098] (3) Preparation process of sustained-release cream: Take 20 mL of oil phase and water phase solution in a 1:1 volume ratio and mix them. Then, homogenize and emulsify at 18-20 kr / min for 5 min. After cooling, the sustained-release cream is obtained. Before mixing, the water and oil phase solutions should be preheated to 70℃. During the homogenization process, the emulsion temperature should also be maintained at 90℃ to avoid the oil phase from cooling and solidifying, which would cause preparation failure.

[0099] II. Preparation of Sustained-Release Capsules

[0100] (1) Preparation of the external phase solution: Take 10 g of gelatin and 3 g of glycerol and add them to 25 g of deionized water. Heat at 65°C and stir until completely dissolved. After dissolution, keep heating at 55°C in preparation for introducing the solution into the microfluidic device.

[0101] (2) Preparation of internal phase emulsion: Take the sustained-release cream obtained in step one, keep it heated at 75°C and stirred at 100 r / min, in preparation for subsequent introduction into microfluidic devices.

[0102] (3) Structure and dimensions of microfluidic devices: The inner tube has an inner diameter of 0.7 mm and a wall thickness of 0.25 mm, the outer tube has an inner diameter of 2.2 mm and a wall thickness of 0.4 mm, and the outlets of the inner and outer tubes are kept flush.

[0103] (4) Preparation process: The two-phase solution was introduced into the microfluidic device by a syringe pump at a flow rate ratio of 0.5:0.8. The outer phase sheared the inner phase at the device inlet to form a core-shell encapsulation structure. The channels through which the two phases were introduced into the microfluidic device were kept warm by wrapping with heating tape. The temperatures were set as follows: 55°C for the outer phase solution channel and 65°C for the inner phase channel. The capsule was dripped into refrigerated caprylic / capric triglyceride and solidified by cooling to obtain a capsule with a core containing honeysuckle sustained-release cream. After preparation, the device and all channels were rinsed with 90°C dimethyl silicone oil to prevent residual inner and outer phase solutions from sticking to the channels after cooling and affecting subsequent preparation. Afterward, the prepared capsules were filtered, collected, rinsed with anhydrous ethanol to remove residual cooling oil, and dried to finally obtain the finished sustained-release capsules. The schematic diagram of the prepared sustained-release capsule is shown below. Figure 1 As shown in the picture, the actual product is as follows. Figure 2 As shown.

[0104] Example 2

[0105] The preparation method of the sustained-release capsules in Example 2 is basically the same as that in Example 1, except that the amounts of silica, beeswax, gelling agent, and base oil added in the preparation step of the oil phase solution of the sustained-release cream are different. Specifically:

[0106] I. Preparation of sustained-release cream

[0107] (1) Preparation of oil phase solution:

[0108] Preparation of GTCC-Estogel solution: Add 2 wt% Estogel (gelling agent, purchased from Dachang Huajia Chemical International Trading Co., Ltd., model: EstogelM) to the base oil GTCC oil (caprylic and caprylic triglycerides) to obtain GTCC-Estogel solution.

[0109] Take 20 mL of GTCC-Estogel solution and add 1 mL of beeswax (5 vol%); the beeswax was melted and liquefied at approximately 70°C before addition. Next, add 300 mg of SiO2 particles (concentration 15 mg / mL) and dissolve.

[0110] The other preparation processes are basically the same as in Example 1.

[0111] Example 3

[0112] The preparation method of the sustained-release capsules in Example 3 is basically the same as that in Example 1, except that the amounts of silica, beeswax, gelling agent, and base oil added in the preparation step of the oil phase solution of the sustained-release cream are different. Specifically:

[0113] I. Preparation of sustained-release cream

[0114] (1) Preparation of oil phase solution:

[0115] Preparation of GTCC-Estogel solution: 7 wt% Estogel (gelling agent, purchased from Dachang Huajia Chemical International Trading Co., Ltd., model: EstogelM) was added to the base oil GTCC oil (caprylic and caprylic triglycerides) to obtain GTCC-Estogel solution.

[0116] Take 20 mL of GTCC-Estogel solution and add 4 mL of beeswax (20 vol%); the beeswax was melted and liquefied at approximately 70°C before addition. Next, add 600 mg of SiO2 particles (concentration 30 mg / mL) and dissolve.

[0117] The other preparation processes are basically the same as in Example 1.

[0118] Comparative Example 1

[0119] Comparative Example 1 served as the control group, consisting solely of a water-soluble honeysuckle fragrance solution at a concentration of 1 vol.

[0120] Comparative Example 2

[0121] The preparation method of the sustained-release agent in Comparative Example 2 is basically the same as that in Example 1, except that step two is omitted and the capsule structure is not prepared, resulting in honeysuckle sustained-release cream.

[0122] The other preparation processes are basically the same as in Example 1.

[0123] Comparative Example 3

[0124] The preparation method of the sustained-release capsules in Comparative Example 3 is basically the same as that in Example 1, except that the amount of gelling agent, wax, and SiO2 particles added in the preparation step of the oil phase solution of the sustained-release cream is different. Specifically:

[0125] I. Preparation of sustained-release cream

[0126] (1) Preparation of oil phase solution:

[0127] Preparation of GTCC-Estogel solution: 1 wt% Estogel (gelling agent, purchased from DKSH Chemical International Trading Co., Ltd., model: Estogel M) was added to the base oil GTCC oil (caprylic / capric triglyceride) to obtain the GTCC-Estogel solution. 1 vol% beeswax was added to the GTCC-Estogel solution; then, 5 mg / mL of SiO2 particles were added to dissolve it. Other preparation procedures were basically the same as in Example 1.

[0128] test:

[0129] The sustained-release capsules obtained in Example 1, the sustained-release cream obtained in Comparative Example 2, and the solution of water-soluble honeysuckle fragrance in Comparative Example 1 were subjected to thermogravimetric analysis to test their sustained-release effects: samples were taken and sent to a thermogravimetric analyzer, the test temperature was set to a constant 40°C, and the test was conducted continuously for 1 hour in an oxygen environment.

[0130] The sustained-release capsules prepared in Examples 1 to 3 above exhibit excellent sustained-release properties. In Comparative Example 3, a sustained-release cream could not be formed for two reasons: firstly, the concentration of added Estogel and wax was too low, preventing the formation of an oleogel network in the oil phase; secondly, the concentration of added SiO2 particles was too low, hindering the formation of a stable water-in-oil emulsion.

[0131] The results of sustained release are as follows Figure 3 As shown, the solution of water-soluble honeysuckle fragrance alone evaporated completely after 30 minutes and had no sustained-release effect; honeysuckle sustained-release cream had about 80% remaining after 60 minutes and had a sustained-release effect; honeysuckle sustained-release capsules had more than 90% remaining after 60 minutes and had a sustained-release effect, and the sustained-release effect was better than that of sustained-release cream.

[0132] The sustained-release capsules of this application utilize microfluidic technology to encapsulate sustained-release cream. Specifically, the hydrophobic particles of the oil phase and the hydrophilic cationic polymer of the aqueous phase in the emulsion form an oil / water interface network due to electrostatic interactions, stabilizing the dispersed micro-aqueous droplets. Furthermore, constructing the oil phase of the emulsion into an oleogel not only further stabilizes the emulsion but also creates a denser molecular network, preventing the rapid evaporation of various water-soluble molecules and reducing the diffusion coefficient, thus achieving superior sustained-release performance. In addition, the capsule's outer material contains amino or carboxyl groups, which can adsorb esters, acids, alcohols, aldehydes, ketones, and other components in the water-soluble substance to be released through hydrogen bonding, further improving the sustained-release performance and extending the sustained-release period, thereby achieving the desired sustained-release effect. Applying the sustained-release capsules of this application to daily chemical and other fields can meet the demand for continuous sustained release of water-soluble substances, creating a new market product.

[0133] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0134] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A sustained-release capsule loaded with water-soluble aroma substances, characterized in that, The capsule includes a core and a capsule wall material encapsulating the core, the core comprising a sustained-release cream comprising an oil phase and an aqueous phase, the oil phase encapsulating the aqueous phase; The aqueous phase comprises a solution containing water-soluble aroma substances and a water-soluble cationic polymer, and the oil phase comprises silica, wax, gelling agent and base oil. The amount of gelling agent added is 2 wt% to 7 wt% based on the mass of the base oil.

2. The sustained-release capsule as described in claim 1, characterized in that, The sustained-release cream meets at least one of the following characteristics: (1) Based on the volume of the aqueous phase, the amount of water-soluble cationic polymer added is 5 mg / mL to 10 mg / mL; (2) Based on the volume of the base oil, the amount of silica added is 15 mg / mL to 30 mg / mL; (3) Based on the volume of the base oil, the amount of wax added is 5 (v / v)%~20 (v / v)%%; (4) The particle size of the silica is 10 nm to 20 nm; (5) The gelling agent includes Estogel; (6) The base oil includes one or more of caprylic / capric triglycerides and silk oil; (7) The wax includes one or more of paraffin wax, beeswax, soybean wax and coconut wax.

3. The sustained-release capsule as described in claim 2, characterized in that, The aqueous phase satisfies at least one of the following characteristics: (1) The water-soluble cationic polymer includes one or more of polyoxyethylene diamine, chitosan and polyethyleneimine; (2) The solution containing water-soluble aroma substances includes one or more of honeysuckle extract, coffee liquid, cocoa extract and wine liquid.

4. The sustained-release capsule as described in any one of claims 1 to 3, characterized in that, The sustained-release cream comprises an oil phase and an aqueous phase in a volume ratio of 1:(0.6~2.5).

5. The sustained-release capsule as described in any one of claims 1 to 3, characterized in that, The capsule wall material includes a hydrophilic material, which includes one or more of gelatin, alginate, carrageenan, and gum arabic.

6. The sustained-release capsule according to any one of claims 1 to 3, characterized in that, The sustained-release capsules have a particle size of 2 mm to 4 mm.

7. A method for preparing a sustained-release capsule loaded with a water-soluble aroma substance, characterized in that, Includes the following steps: A solution containing water-soluble aroma substances is mixed with a cationic polymer to obtain an aqueous phase; Silica particles, wax, gelling agent and base oil are mixed to obtain the oil phase; The aqueous phase and the oil phase are mixed and emulsified, and then cooled to prepare a sustained-release cream. The sustained-release cream is encapsulated with capsule wall material to prepare a sustained-release capsule.

8. The method for preparing the sustained-release capsule as described in claim 7, characterized in that, The volume ratio of the oil phase to the water phase is 1:(0.6~2.5). And / or, the rotation speed of the emulsification process is 18 kr / min to 20 kr / min, and the emulsification time is 3 min to 8 min.

9. The method for preparing the sustained-release capsule as described in claim 7, characterized in that, The step of encapsulating the sustained-release cream with the capsule wall material is performed using microfluidic technology, with the capsule wall material serving as the continuous phase and the sustained-release cream serving as the dispersed phase. And / or, prior to the step of encapsulating the sustained-release cream with the capsule wall material, the method further includes: The sustained-release cream was preheated and stirred at 70℃~80℃ and 100r / min~200r / min. The capsule wall material was preheated and stirred at 50℃~60℃ and 100r / min~200r / min.

10. The method for preparing the sustained-release capsule according to any one of claims 7 to 9, characterized in that, In the process of preparing sustained-release capsules using microfluidic technology, the flow ratio of the sustained-release cream to the capsule wall material is 1:(1~2).

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