Preparation method of microcapsule tobacco flavor essence

Abstract

The invention relates to a preparation method of microcapsule tobacco flavor and essence, and belongs to the technical field of flavor and essence. According to the method, a whey protein and tea polyphenol composite system is adopted as a wall material, a stable solution is formed through specific proportion matching and pH adjustment, a mesoporous silica nano-carrier is introduced when a core material is treated, the anchoring effect on essence molecules is improved, and the flavor and essence are prepared. In the emulsification stage, a natural emulsifier compounded from gardenia polysaccharide and lecithin is adopted, a stable emulsion is formed through high-speed shearing and high-pressure homogenization, uniform micro-droplets are formed through ultrasonic atomization and fluidized bed pre-coating, and a wall material forms a compact structure by combining a pulsed electric field assisted spray drying technology, so that the wall material is formed. The product is subjected to fluidized bed secondary drying and rotary drum polishing treatment, so that the fluidity and stability are improved; the encapsulation efficiency of the microcapsule prepared by the method reaches 93% or above, the retention rate exceeds 92% after heat treatment at 120 DEG C, the angle of repose is reduced to about 26 degrees, and the microcapsule is suitable for embedding protection of various types of tobacco essences.

Description

Technical Field

[0001] This invention relates to the field of fragrance and flavor preparation technology, specifically a method for preparing microcapsule tobacco fragrance and flavor. Background Technology

[0002] Microencapsulation technology is often used to encapsulate and protect tobacco flavorings and fragrances, with the aim of slowing down aroma release and improving stability.

[0003] Existing methods mostly employ single-layer wall materials and conventional spray drying processes, which have some shortcomings in practical applications. The choice of wall materials is relatively limited, resulting in limited protection for highly volatile fragrance components. Aroma loss is easily caused during processing, the stability of the emulsion system is not ideal, which affects the subsequent encapsulation effect, and the temperature control during drying is not precise enough, which may lead to cracks on the surface of the microcapsules or a loose structure, affecting the encapsulation effect. There is also room for improvement in product flowability, as adhesion or clumping sometimes occurs. These factors collectively affect the quality stability and application effect of microcapsule products, requiring improvements in both materials and processes. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing microcapsule tobacco flavorings to solve the problems mentioned in the background art.

[0005] A method for preparing microcapsule tobacco flavoring includes the following steps: S1. Dissolve whey protein in warm water, then add tea polyphenol aqueous solution, and stir slowly to mix the two thoroughly to obtain wall material solution; S2, mix the core material fragrance with mesoporous silica nanocarrier (pore size 4nm) to obtain a core material mixture; S3, the treated core material is slowly added to the wall material solution, and high-speed shearing is started at the same time. Natural polysaccharides and lecithin are selected as emulsifiers and added to the shearing fluid in two batches to obtain the emulsion. S4, the emulsion obtained above is atomized using high-frequency ultrasonic atomization to form fine microdroplets; S5, microdroplets are pre-coated in a fluidized bed to form a uniform film on the surface of the initially coated microcapsules; S6, which adds an electric field-assisted drying method to the conventional spray drying process for microcapsules; S7, the dried microcapsules are then subjected to a secondary fluidized bed drying process to further reduce the moisture content; S8. Finally, the particles of suitable size are collected by grading through a vibrating screen. The microcapsule products of suitable size are then placed in a very low-speed rotating drum for rolling to reduce the angle of repose.

[0006] Furthermore, in step S1, the whey protein is dissolved in water at a temperature maintained at 45±2℃, with a concentration controlled between 7.8-8.2%. A 0.1mol / L sodium hydroxide solution is used to adjust the pH to precisely 7.0-7.2. When adding the tea polyphenol aqueous solution, the tea polyphenol concentration is controlled at 1.1-1.3%, with a mass ratio to whey protein of 1:7.8-8.2. The stirring speed is 600±50 rpm, and the stirring time is 15-18 minutes.

[0007] Furthermore, in S1, for strongly hydrophilic flavorings (such as certain alcohols), the proportion of tea polyphenols can be appropriately increased (e.g., adjusted from 1:8 to 1:7.5) to utilize the stronger hydrophilicity and intermolecular forces of polyphenols to form a tighter network structure and lock in water-soluble components; for highly hydrophobic flavorings (such as terpenes), the proportion of tea polyphenols can be appropriately reduced (e.g., adjusted to 1:8.5), and a very small amount (0.1%-0.2%) of a more hydrophobic natural component, such as the glycoprotein component in gum arabic, can be added to whey protein to improve the oil-water interfacial tension and make the hydrophobic core material more completely encapsulated.

[0008] Furthermore, during core material treatment, the mass ratio of fragrance to mesoporous silica is 9.8:1-10.2:1, the ultrasonic water temperature is 35±1℃, and the treatment time is 18-22 minutes.

[0009] Furthermore, in step S3, the mass ratio of the core material to the wall material during mixing is 1:1.45-1.55, the mixing temperature is maintained at 38-40℃, the high-speed shear emulsification speed is 9500-10500 rpm, the processing time is 3.5-4.5 minutes, the high-pressure homogenization pressure is 38-42 MPa, the number of cycles is 2-4, the amount of emulsifier added is 0.75-0.85% of the total mass, and the natural polysaccharide selected is gardenia polysaccharide, with a mass ratio of gardenia polysaccharide to lecithin of 1.9:1-2.1:1.

[0010] Furthermore, in S3, an online particle size monitor is installed during the emulsification stage to monitor the emulsion particle size in real time. When the particle size is detected to deviate from the set range, the system automatically fine-tunes the pressure or number of cycles of high-pressure homogenization. When the particle size is detected to be too large, the homogenization pressure can be automatically increased from 40MPa to 42MPa and an additional cycle can be added to achieve the purpose of real-time monitoring and adjustment.

[0011] Furthermore, in S4, the ultrasonic atomization frequency is 78-82kHz, and the atomization volume is 4.8-5.2L / h. There is a transducer at the bottom of the atomizer, which is like a small speaker, but the vibration frequency is very high, reaching tens of thousands of times per second. This high-frequency vibration is transmitted to the liquid above, forming extremely fine waves on the surface of the liquid. At the crest of the vibration, the liquid is thrown upward to form very fine liquid columns. These liquid columns break at the top and become countless uniform micron-sized droplets, just like continuously generated ultrafine water mist.

[0012] Furthermore, in S5, the temperature inside the fluidized bed is controlled between 39-41℃, the airflow velocity is 0.75-0.85m / s, the pre-coating time is 11-13 minutes, and the spray pressure of the wall material solution is 0.15-0.25MPa. During the pre-coating process, after the emulsion is atomized by ultrasonic waves, the original emulsion becomes an extremely fine and uniform "cold mist" (because it is not generated by heating). This mist-like microdroplet group is then introduced into the fluidized bed, encounters the wall material solution, and forms a uniform film on the surface of the microcapsule.

[0013] Furthermore, in step S6, a spray drying tower is used for spray drying. The inlet temperature is 113-117℃, and the outlet temperature is 67-69℃. The pulse electric field parameters are: field strength 14.5-15.5kV / cm, pulse width 95-105μs, and frequency 950-1050Hz. A humidity sensor is installed inside the spray drying tower to monitor the humidity of the exhaust gas. The humidity of the exhaust gas can indirectly reflect the drying rate. When the humidity drops sharply, it indicates that the drying is too fast. The inlet temperature can be automatically fine-tuned inside the spray drying tower (e.g., reduced from 115℃ to 113℃) and the electric field pulse frequency can be adjusted simultaneously to slow down the drying speed and avoid excessively rapid surface hardening. To prevent cracking, dynamic control can better cope with changes in ambient temperature and humidity, reducing batch-to-batch differences. The exhaust gas temperature from the spray drying tower is still relatively high (approximately 65-70℃) and contains a certain amount of humidity. The latent heat and sensible heat in the exhaust gas are recovered using a heat pump system to preheat the inlet gas entering the fluidized bed, raising the inlet gas temperature from room temperature to 30-35℃. This reduces the energy consumption of the fluidized bed heater and makes the fluidized bed temperature control more stable, reducing the thermal shock to the microcapsules. In S7, the secondary drying uses a fluidized bed at a temperature of 55-60℃ for 25-35 minutes, and the final product moisture content is controlled at 2.3-2.7%.

[0014] Furthermore, in step S8, the vibrating screen grading uses a 100-120 mesh screen, and the grading time is 8-12 minutes. The graded microcapsule product is rolled in a very low-speed rotating drum for 15-20 minutes, while extremely dry, low-temperature air is blown in. This gentle mechanical motion makes the tiny protrusions or burrs on the surface of the microcapsules smoother through mutual friction, while further removing any trace amounts of moisture that may be adsorbed on the surface. This can slightly but significantly improve the product's flowability and long-term storage stability, and the angle of repose is expected to decrease from 28° to about 25°. During packaging, the nitrogen purity is required to be above 99.5%, the packaging residual pressure is 0.045-0.055 MPa, the humidity of the production environment is controlled at 28-32%, and the water temperature is maintained at 20-25°C.

[0015] By adopting the above technical solutions, common problems in the microencapsulation process, such as low encapsulation rate, poor thermal stability, and poor product uniformity, have been systematically solved.

[0016] Compared with the prior art, the beneficial effects of the present invention are: the microcapsule tobacco flavoring essence, After dissolving whey protein in 45°C warm water and adjusting the pH to 7.0 to 7.2, a specific concentration of tea polyphenol solution is added, and the mixture is stirred at 600 rpm for 16 minutes to form a stable complex. This natural wall material has better density and heat resistance, providing effective protection for the core material. In the core material processing stage, mesoporous silica nanocarriers are introduced. Fragrances and mesoporous silica with a pore size of 4 nanometers are mixed at a mass ratio of 10:1 and ultrasonically treated at 35 degrees Celsius for 20 minutes. This step anchors fragrance molecules in the nanopores, significantly reducing the loss of volatile components during processing. The emulsification process utilizes a natural system of gardenia polysaccharide and lecithin, added in a 2:1 ratio, with the total amount controlled at 0.8%. Under high-speed shearing at 10,000 rpm and high-pressure homogenization at 40 MPa, an emulsion with excellent stability is formed. This emulsification system avoids the off-odor problem of synthetic emulsifiers, resulting in a more robust interfacial film. The coating process employs a multi-stage treatment method. Uniform microdroplets are generated through 80 kHz ultrasonic atomization, and pre-coating is carried out in a fluidized bed to form a nascent wall material film. This step ensures uniform distribution of the wall material and guarantees consistent product morphology. During the drying stage, pulsed electric field-assisted technology is used. At an inlet temperature of 115 degrees Celsius, a pulsed electric field with a field strength of 15 kV per centimeter and a frequency of 1000 Hz is applied to cause the wall material molecules to align in a dense structure. This treatment improves the mechanical strength of the wall material and keeps the encapsulation rate stable at over 93%. The parameters are automatically adjusted by monitoring the humidity of the exhaust gas to ensure process stability. Post-processing includes fluidized bed secondary drying and rotary drum polishing. These steps further reduce the product moisture content, improve particle flowability, and reduce the angle of repose to about 26 degrees, which is beneficial for subsequent processing applications. This method also demonstrates good adaptability. For hydrophilic flavorings, the proportion of tea polyphenols can be increased to 1:7.5, utilizing the hydrophilicity of polyphenols to form a tighter network; for hydrophobic flavorings, the proportion of tea polyphenols can be reduced to 1:8.5, and 0.15% arabinoprotein can be added to improve the oil-water interfacial tension. This flexibility makes it suitable for various tobacco flavorings. The final product retains over 92% of the core material after heat treatment at 120 degrees Celsius, and has good fluidity, meeting the requirements for tobacco product processing. The entire process uses natural raw materials, with precise parameter control, and is feasible for industrial production. By organically combining various technical means, this method systematically solves common problems in the microencapsulation process, such as low encapsulation efficiency, poor thermal stability, and poor product uniformity. In particular, the introduction of nanocarriers and the application of electric field-assisted drying provide new ideas for microcapsule preparation technology. The entire process uses natural raw materials, avoiding the use of synthetic materials, which meets the safety requirements of the food and tobacco industries. The parameterized control method and the application of online monitoring also make this method feasible for industrial production, ensuring the stability of product quality. The final microcapsule product still has a core material retention rate of over 92% after heat treatment at 120 degrees Celsius and has good flowability, which can meet the actual needs of tobacco product processing and application. Attached Figure Description

[0017] Figure 1 This is a line graph showing the performance index of the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. 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.

[0019] Please see Figure 1 This invention provides a technical solution: a method for preparing microcapsule tobacco flavoring. Experiment 1: Reference Parameter Experiment step: S1: Dissolve whey protein in water at 45℃ to a concentration of 8.0%, adjust the pH to 7.1 with 0.1M NaOH, add 1.2% tea polyphenol solution (tea polyphenol: protein = 1:8), and stir at 600 rpm for 16 min; S2: Take ethyl acetate fragrance (hydrophobic) and mesoporous SiO2 (10:1) and sonicate at 35℃ for 20 min; S3: The core material and wall material are mixed at a ratio of 1:1.5, and sheared at 10,000 rpm for 4 minutes at 40°C. 0.8% emulsifier (gardenia polysaccharide: lecithin = 2:1) is added, and the mixture is homogenized and cyclically run at 40 MPa for 3 times. S4-S5: 80kHz atomization, fluidized bed at 40℃ and 0.8m / s for 12min pre-coating; S6-S7: Spray drying (115℃ inlet, 68℃ outlet), electric field assisted (15kV / cm, 1kHz), secondary drying (58℃, 30min); S8: Classified by 120 mesh sieve, low-speed rolling for 18 minutes, and packaged with nitrogen.

[0020] Results Table 1: Benchmark Experiment Performance

[0021] Experiment 2: Blending with highly hydrophilic flavorings (increasing the proportion of tea polyphenols) Preparation steps: S1: Dissolve whey protein in deionized water at 45℃ to prepare an 8.0% solution. Adjust the pH to 7.0 with 0.1 mol / L NaOH solution. Slowly add 1.25% tea polyphenol aqueous solution (tea polyphenol:whey protein mass ratio = 1:7.5) at 600 rpm and stir continuously for 17 minutes. S2: Take hydrophilic fragrance (phenylethanol) and mesoporous silica nanocarrier at a mass ratio of 10:1, and ultrasonically treat in a 35℃ water bath for 20 minutes; S3: Mix the core material mixture and the wall material solution at a mass ratio of 1:1.5, maintain the temperature at 38℃, and shear at high speed at 10000rpm for 4 minutes. Add 0.8% of the total emulsifier (gardenia polysaccharide: lecithin = 2:1) in two batches, and then homogenize and cycle 3 times under a pressure of 40MPa. S4-S5: The emulsion is atomized using an 80kHz ultrasonic atomizer, and the atomized droplets enter the fluidized bed. Under the conditions of 40℃ and 0.8m / s airflow, they are pre-coated with the wall material solution sprayed in the opposite direction for 12 minutes. S6-S7: Pre-coated microcapsules enter the spray drying tower with an inlet temperature of 115℃ and an outlet temperature of 68℃, while a pulsed electric field with a strength of 15kV / cm and a frequency of 1kHz is applied simultaneously. They are then subjected to secondary drying in a fluidized bed at 58℃ for 30 minutes. S8: After drying, the product is graded by a 120-mesh vibrating screen. Qualified products are placed in a low-speed rotating drum, and 25°C dry air is blown in and the drum is rolled for 18 minutes. Finally, the product is packaged in a nitrogen environment.

[0022] Results Table 2: Compatibility Experimental Performance of Highly Hydrophilic Fragrances

[0023] Experiment 3: Blending with highly hydrophobic flavorings (reducing the proportion of tea polyphenols + adding hydrophobic components) Preparation steps: S1: Prepare an 8.0% whey protein solution (45℃, pH 7.2). Add 1.18% tea polyphenol solution (tea polyphenol: protein = 1:8.5), and simultaneously add 0.15% of the total mass of the wall material containing gum arabic protein. Stir at 600 rpm for 16 minutes. S2: Mix hydrophobic fragrance (limonene) with mesoporous SiO2 at a mass ratio of 10:1 and sonicate at 35°C for 22 minutes; S3-S8: The subsequent steps are exactly the same as those in the benchmark experiment.

[0024] Results Table 3: Compatibility Experimental Performance of Highly Hydrophobic Fragrances

[0025] Experiment 4: Exploring the High Load Ratio of Core Material Preparation steps: S1: The procedure is the same as the baseline experiment; S2: Increase the mass ratio of fragrance to mesoporous SiO2 to 12:1, and sonicate at 35°C for 20 minutes; S3-S8: The subsequent steps are exactly the same as those in the benchmark experiment.

[0026] Results Table 4: Experimental Performance of High Core Material Load

[0027] Experiment 5: Emulsifier ratio adjustment (reducing the polysaccharide ratio) Preparation steps: S1-S2: The steps are the same as the baseline experiment; S3: The mixing conditions for the core and wall materials remain unchanged. The total amount of emulsifier added remains 0.8%, but the mass ratio of gardenia polysaccharide to lecithin is changed to 1.5:1. The high-speed shearing and homogenization conditions remain unchanged. S4-S8: The subsequent steps are exactly the same as those in the benchmark experiment.

[0028] Results Table 5: Experimental Performance of Emulsifier Ratio Adjustment

[0029] Experiment 6: Comparison of Low Atomization Frequency Preparation steps: S1-S3: The steps are the same as the baseline experiment; S4: Lower the frequency of the ultrasonic nebulizer to 70kHz, while keeping other nebulization parameters unchanged; S5-S8: The subsequent steps are exactly the same as those in the benchmark experiment.

[0030] Results Table 6: Experimental performance at low fogging frequency

[0031] Experiment 7: Shortening the pre-coating time Preparation steps: S1-S4: The steps are the same as in the baseline experiment; S5: Reduce the pre-coating time of microdroplets in the fluidized bed to 8 minutes (fluidized bed temperature and airflow velocity remain unchanged). S6-S8: The subsequent steps are exactly the same as those in the benchmark experiment.

[0032] Results Table 7: Experimental performance of short pre-coating time

[0033] Experiment 8: Low drying temperature trial Preparation steps: S1-S5: The steps are the same as in the baseline experiment; S6: Reduce the inlet temperature of the spray drying tower to 105℃, and the outlet temperature to approximately 62℃. The pulsed electric field parameters remain unchanged. S7-S8: The subsequent steps are exactly the same as those in the benchmark experiment.

[0034] Results Table 8: Experimental performance at low drying temperature

[0035] Experiment 9: Low Electric Field Frequency Comparison Preparation steps: S1-S5: The steps are the same as in the baseline experiment; S6: Spray drying temperature parameters are the same as in the baseline experiment. Adjust the frequency of the pulsed electric field to 500Hz (field strength and pulse width remain unchanged); S7-S8: The subsequent steps are exactly the same as those in the benchmark experiment.

[0036] Results Table 9: Experimental performance at low electric field frequencies

[0037] Experiment 10: Cancel post-processing polishing Preparation steps: S1-S7: All steps are exactly the same as in the benchmark experiment; S8: After the dried product is graded by a 120-mesh vibrating screen, the low-speed rolling polishing step is omitted, and it is directly packaged with nitrogen.

[0038] Results Table 10: Experimental performance without polishing treatment

[0039] Overall Comparison Table

[0040] Recommended Process Configuration Table for Different Flavor Types

Claims

1. A method for preparing microcapsule tobacco flavoring, characterized in that, Includes the following steps: S1. Dissolve whey protein in warm water, then add tea polyphenol aqueous solution, and stir slowly to mix the two thoroughly to obtain wall material solution; S2, mix the core material fragrance with mesoporous silica nanocarrier (pore size 4nm) to obtain a core material mixture; S3, the treated core material is slowly added to the wall material solution, and high-speed shearing is started at the same time. Natural polysaccharides and lecithin are selected as emulsifiers and added to the shearing fluid in two batches to obtain the emulsion. S4, the emulsion obtained above is atomized using high-frequency ultrasonic atomization to form fine microdroplets; S5, microdroplets are pre-coated in a fluidized bed to form a uniform film on the surface of the initially coated microcapsules; S6, which adds an electric field-assisted drying method to the conventional spray drying process for microcapsules; S7, the dried microcapsules are then subjected to a secondary fluidized bed drying process to further reduce the moisture content; S8. Finally, the particles of suitable size are collected by grading through a vibrating screen. The microcapsule products of suitable size are then placed in a very low-speed rotating drum for rolling to reduce the angle of repose.

2. The method for preparing a microcapsule tobacco flavoring according to claim 1, characterized in that, In step S1, the whey protein is dissolved in water at a temperature maintained at 45±2℃, with a concentration controlled between 7.8% and 8.2%. A 0.1 mol / L sodium hydroxide solution is used to adjust the pH precisely to 7.0-7.

2. When adding the tea polyphenol aqueous solution, the tea polyphenol concentration is controlled at 1.1%-1.3%, and the mass ratio of tea polyphenols to whey protein is maintained at 1:7.8-8.

2. The stirring speed is 600±50 rpm, and the stirring time is 15-18 minutes.

3. The method for preparing a microcapsule tobacco flavoring according to claim 1, characterized in that, In S1, for strongly hydrophilic flavorings (such as certain alcohols), the proportion of tea polyphenols can be appropriately increased (e.g., adjusted from 1:8 to 1:7.5) to utilize the stronger hydrophilicity and intermolecular forces of polyphenols to form a tighter network structure and lock in water-soluble components; for highly hydrophobic flavorings (such as terpenes), the proportion of tea polyphenols can be appropriately reduced (e.g., adjusted to 1:8.5), and a very small amount (0.1%-0.2%) of a more hydrophobic natural component, such as the glycoprotein component in gum arabic, can be added to whey protein to improve the oil-water interfacial tension and make the hydrophobic core material more completely encapsulated.

4. The method for preparing a microcapsule tobacco flavoring according to claim 1, characterized in that, In step S2, during core material treatment, the mass ratio of fragrance to mesoporous silica is 9.8:1-10.2:1, the ultrasonic water temperature is 35±1℃, and the treatment time is 18-22 minutes.

5. The method for preparing a microcapsule tobacco flavoring according to claim 1, characterized in that, In step S3, the mass ratio of the core material to the wall material is 1:1.45-1.55, the mixing temperature is maintained at 38-40℃, the high-speed shear emulsification speed is 9500-10500 rpm, the processing time is 3.5-4.5 minutes, the high-pressure homogenization pressure is 38-42 MPa, the number of cycles is 2-4, the amount of emulsifier added is 0.75-0.85% of the total mass, and the natural polysaccharide is selected from gardenia polysaccharide, with a mass ratio of gardenia polysaccharide to lecithin of 1.9:1-2.1:

1.

6. The method for preparing a microcapsule tobacco flavoring according to claim 5, characterized in that, In step S3, an online particle size monitor is installed during the emulsification stage to monitor the emulsion particle size in real time. When the particle size deviates from the set range, the system automatically adjusts the pressure or number of cycles of high-pressure homogenization. When the particle size is detected to be too large, the homogenization pressure can be automatically increased from 40MPa to 42MPa and an additional cycle can be added to achieve the purpose of real-time monitoring and adjustment.

7. The method for preparing a microcapsule tobacco flavoring according to claim 1, characterized in that, In S4, the ultrasonic atomization frequency is 78-82kHz, and the atomization volume is 4.8-5.2L / h. There is a transducer at the bottom of the atomizer, which is like a small speaker, but the vibration frequency is very high, reaching tens of thousands of times per second. This high-frequency vibration is transmitted to the liquid above, forming extremely fine waves on the surface of the liquid. At the peak of the vibration, the liquid is thrown upward to form very fine liquid columns. These liquid columns break at the top and become countless uniform micron-sized droplets, just like continuously generated ultrafine water mist.

8. The method for preparing a microcapsule tobacco flavoring according to claim 7, characterized in that, In step S5, the temperature inside the fluidized bed is controlled between 39-41℃, the airflow velocity is 0.75-0.85m / s, the pre-coating time is 11-13 minutes, and the spray pressure of the wall material solution is 0.15-0.25MPa. During the pre-coating process, after the emulsion is atomized by ultrasonic waves, the original emulsion becomes an extremely fine and uniform "cold mist" (because it is not generated by heating). This mist-like microdroplet group is then introduced into the fluidized bed, encounters the wall material solution, and forms a uniform film on the surface of the microcapsule.

9. The method for preparing a microcapsule tobacco flavoring according to claim 1, characterized in that, In step S6, a spray drying tower is used for spray drying. The inlet temperature is 113-117℃, and the outlet temperature is 67-69℃. The pulse electric field parameters are: field strength 14.5-15.5kV / cm, pulse width 95-105μs, and frequency 950-1050Hz. A humidity sensor is installed inside the spray drying tower to monitor the humidity of the exhaust gas. The humidity of the exhaust gas can indirectly reflect the drying rate. When the humidity drops sharply, it indicates that the drying is too fast. The spray drying tower can automatically fine-tune the inlet temperature (e.g., from 115℃ to 113℃) and simultaneously adjust the electric field pulse frequency to slow down the drying speed and avoid surface hardening and cracking. Dynamic control can better cope with changes in ambient temperature and humidity, reducing batch-to-batch differences. The exhaust gas temperature from the spray drying tower is still relatively high (about 65-70℃) and contains a certain amount of humidity. The latent heat and sensible heat in the exhaust gas are recovered by a heat pump system to preheat the inlet gas entering the fluidized bed, raising the inlet gas temperature from room temperature to 30-35℃. This reduces the energy consumption of the fluidized bed heater and makes the fluidized bed temperature control more stable, reducing the thermal shock to the microcapsules. In S7, the secondary drying adopts a fluidized bed at a temperature of 55-60℃ for 25-35 minutes, and the moisture content of the final product is controlled at 2.3-2.7%.

10. The method for preparing a microcapsule tobacco flavoring according to claim 1, characterized in that, In step S8, a 100-120 mesh screen is used for grading using a vibrating screen, and the grading time is 8-12 minutes. The graded microcapsule products are rolled in a very low-speed rotating drum for 15-20 minutes while extremely dry, low-temperature air is blown in. This gentle mechanical motion makes the tiny protrusions or burrs on the surface of the microcapsules smoother through mutual friction, while further removing any trace amounts of moisture that may be adsorbed on the surface. This can slightly but significantly improve the product's flowability and long-term storage stability, and the angle of repose is expected to decrease from 28° to about 25°. During packaging, the nitrogen purity is required to be above 99.5%, the packaging residual pressure is 0.045-0.055 MPa, the humidity of the production environment is controlled at 28-32%, and the water temperature is maintained at 20-25°C.

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