Preparation method of tea stem-based flavoring granular material and product and application of tea stem-based flavoring granular material

Abstract

The invention provides a preparation method of a tea stem-based flavoring granular material as well as a product and application thereof, the preparation method comprises the following steps: (1) crushing tea stems, and then carrying out hydrothermal reaction with water to obtain tea stem-based hydrothermal carbon; and (2) mixing the tea stem-based hydrothermal carbon obtained in the step (1) with liquid paraffin, an essence solution and high-thermal-conductivity nanosheets, and air-drying to obtain the tea stem-based perfuming granular material. Compared with a traditional commercial porous carbon essence-loaded material, the prepared tea-stem-based hydrothermal carbon essence-loaded material has the same essence adsorption amount, and after a phase-change material liquid paraffin and a high-thermal-conductivity material boron nitride are used, the normal-temperature storage stability and the slow-release performance of the essence are remarkably improved; the adsorbent can efficiently and rapidly adsorb essence, and has a wide application prospect.

Description

Technical Field

[0001] The invention belongs to the technical field of cigarette filter materials, and particularly relates to a preparation method of a tea stem-based aroma granular material, a product thereof and an application thereof. Background Art

[0002] At present, the technological innovation of cigarette products mainly focuses on the innovation of filter rod improvement technology. The innovation of cigarette filter rod technology plays a vital role in the development of cigarette products and the operation of brand markets. Among them, adding flavoring functional carrier materials to cigarette filter rods is an important means to improve the taste and quality of cigarettes. There are many ways to add flavor to cigarette filter rods, such as solvent flavoring, adsorbent flavoring, fragrance line flavoring, capsule method and composite flavoring method. The adsorbent method uses porous solid adsorbents to adsorb or inclusion compounds to encapsulate flavors and fragrances, and then the adsorbent or inclusion compound is added to the filter material to make a composite filter. The adsorbent method can delay the volatilization loss of flavors and ensure the uniform release of aroma during the smoking process. In addition, adding flavors to cigarette filter rods can not only prevent the added flavors from participating in the combustion reaction of tobacco shreds and causing waste, but also realize the efficient release control of flavor substances by sucking the heat in the burning smoke, while avoiding the loss of flavors during the static burning of cigarettes; reducing the interception of flavors by tobacco shreds and filter tips, increasing the transfer efficiency, and increasing the content of low-boiling point flavor substances in mainstream smoke. Ultimately, the aroma sensory quality of cigarette smoking is improved. At present, the tobacco industry uses more binary and ternary composite flavoring filter rods, which have a complex preparation process and high cost. Porous materials, due to their large specific surface area and certain pores, can not only absorb harmful components in smoke (such as heavy metals, tar and other substances), reduce the harm to the body of smokers, but also give cigarettes a unique flavor by loading and releasing flavors. Among them, porous materials are widely used in the flavoring of cigarette filter rods as flavor loading materials because of their certain specific surface area, pores and excellent stability.

[0003] CN117482916A discloses an adsorbent material and a preparation method thereof for preparing cigarette filter rods and a cigarette solid filter rod, wherein the adsorbent material comprises the following components in parts by weight: 30-50 parts of polylactic acid-glycolic acid copolymer, 15-30 parts of modified starch, 10-25 parts of maltodextrin-modified vermiculite powder, and 5-12 parts of a wetting and dispersing agent; the modified starch is a mixture of maltodextrin and hydroxypropyl starch; the wetting and dispersing agent contains a nonionic fluorocarbon segment. The adsorbent material described in the invention is used for cigarette filter rods, which can solve the problem that the current cigarette holder filter rod material is difficult to biodegrade and easily causes environmental pollution, and can also improve the filtering effect on harmful substances such as tar and carbon monoxide, which is conducive to application.

[0004] CN116268563A discloses a functional plant particle for filter rod flavoring, and a preparation method and application thereof. The functional plant particle is prepared from natural plant powder, phase change polymer material, and tobacco flavoring, wherein the weight of natural plant powder accounts for 30%-70%, the weight of phase change polymer material accounts for 20%-60%, and the weight of tobacco flavoring accounts for 5%-20%. First, the tobacco flavoring is evenly mixed with the phase change polymer material in a molten state, and then mixed and kneaded evenly with the natural plant powder, and the particles for filter rod flavoring are prepared by an extrusion granulation method. The functional plant particle preparation process of the invention has almost zero loss of flavor substances, can retain the flavor substances of the particles themselves to the greatest extent, has a high adsorption capacity of tobacco flavoring, a good embedding effect, is not easy to volatilize, has a long fragrance storage time, and has high production efficiency.

[0005] Although more and more granular materials are used in cigarette products in the prior art, they still have problems such as poor adsorption effect and low stability of flavor release in actual application. Therefore, it is of great significance to develop a granular product with better adsorption effect and more stable flavor release. Summary of the invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a method for preparing a tea stem-based aroma-imparting granular material, and its products and applications. The technical solution of the present invention not only solves the current problems of low waste resource utilization efficiency, poor thermal conductivity of hydrothermal charcoal, and difficulty in removing impurities and retaining its own aroma, but also solves the problem that the current commercial activated carbon has too high specific surface area and too many internal micropores, which is not conducive to the sustained release of flavors.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a method for preparing a tea stem-based aroma granular material, the preparation method comprising:

[0009] (1) crushing tea stems and then subjecting them to a hydrothermal reaction with water to obtain tea stem-based hydrothermal charcoal;

[0010] (2) Mixing the tea stem-based hydrothermal charcoal obtained in step (1) with liquid paraffin, essence solution, and high thermal conductivity nanosheets, and air-drying the mixture to obtain the tea stem-based aroma-imparting granular material.

[0011] The method of the present invention utilizes natural plant tea stems as raw materials, removes part of the lignocellulose through a hydrothermal treatment technology, etches the surface of the tea stems, prepares tea stem hydrothermal charcoal, removes the tea stems' own impurities while retaining part of their own fragrance, and can also additionally load a certain amount of essence matching their fragrance to comprehensively improve the taste of cigarettes, which will provide technical support for developing composite cigarette filter rods with special flavors and creating special products, and can also achieve high added value utilization of natural plant tea stems.

[0012] In particular, after the hydrothermal carbonization treatment, the present invention composites the tea stem-based hydrothermal charcoal with liquid paraffin and boron nitride, wherein the liquid paraffin is used as a low-temperature organic phase change material, has good chemical stability and low phase change temperature, and the liquid paraffin is wrapped on the surface of the hydrothermal charcoal, which is beneficial to improving the storage stability of the flavor and the low-temperature release performance of the flavor; the flavor and the high thermal conductivity nanosheets are evenly mixed and loaded into the pores of the hydrothermal charcoal, and the high thermal conductivity material can improve the overall thermal conductivity of the material and enhance the low-temperature release of the flavor. Through the above operation, a tea stem-based aromatizing granular material with high adsorption capacity, strong stability and excellent release performance can be prepared.

[0013] Preferably, after the crushing in step (1), the tea stems are sieved.

[0014] Preferably, the mesh number of the sieving is 30-80 meshes, for example, it can be 40 meshes, 50 meshes, 60 meshes or 70 meshes.

[0015] Preferably, the mass ratio of the tea stems to water in step (1) is 1:(8-15), for example, it can be 1:9, 1:10, 1:11, 1:12, 1:13 or 1:14, etc.

[0016] Preferably, a catalyst is added during the hydrothermal reaction in step (1).

[0017] Preferably, the catalyst is added in an amount of 0.5-2% of the total amount of water and tea stems, for example, 0.6%, 0.8%, 1%, 1.2%, 1.4%, 1.6% or 1.8%, etc.

[0018] Preferably, the catalyst is a metal chloride.

[0019] Preferably, the metal chloride comprises FeCl 3 、AlCl 3 or ZnCl 2 Any one or a combination of at least two of the following.

[0020] Preferably, the metal chloride is ZnCl 2 .

[0021] Preferably, the temperature of the hydrothermal reaction in step (1) is 150-200°C (for example, 160°C, 170°C, 180°C, 190°C or 200°C, etc.), and the time is 30-90min (for example, 40min, 50min, 60min, 70min, 80min or 90min, etc.).

[0022] Preferably, the reaction is carried out under stirring.

[0023] Preferably, the stirring speed is 150-300 rpm, for example, it can be 160 rpm, 180 rpm, 200 rpm, 220 rpm, 240 rpm, 260 rpm or 280 rpm.

[0024] Preferably, after the hydrothermal reaction in step (1), the reaction product is washed with water, filtered and dried.

[0025] Preferably, the drying temperature is 100-120°C, for example, it may be 102°C, 104°C, 106°C, 108°C, 110°C, 112°C, 114°C, 116°C or 118°C.

[0026] Preferably, the mass ratio of the tea stem-based hydrothermal charcoal to liquid paraffin, essence solution, and high thermal conductivity nanosheets in step (2) is 1:(0.1-0.5):(1-3):(0.1-0.2).

[0027] Wherein “0.1-0.5” can be 0.15, 0.2, 0.25, 0.3, 0.35, 0.4 or 0.45, etc.;

[0028] "1-3" can be 1.1, 1.3, 1.5, 1.7, 1.9, 2, 2.2, 2.5, 2.7 or 2.9, etc.;

[0029] “0.1-0.2” can be 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18 or 0.19, etc.

[0030] Preferably, the boiling point of the liquid paraffin in step (2) is higher than 300°C, and the viscosity is 10-30mPa·s (for example, 12mPa·s, 15mPa·s, 18mPa·s, 20mPa·s, 22mPa·s, 25mPa·s or 28mPa·s, etc.) at 20-60°C (for example, 25°C, 30°C, 35°C, 40°C, 45°C, 50°C or 55°C).

[0031] Preferably, the high thermal conductivity nanosheet in step (2) is any one of boron nitride, aluminum nitride or silicon carbide, or a combination of at least two of them.

[0032] Preferably, the high thermal conductivity nanosheet is boron nitride.

[0033] Preferably, the size of the high thermal conductive nanosheet in step (2) is a sheet diameter of 0.5-2 μm (for example, it can be 0.6 μm, 0.7 μm, 0.8 μm, 0.9 μm, 1 μm, 1.2 μm, 1.5 μm, 1.7 μm or 1.9 μm, etc.), and a thickness of 2-10 nm (for example, it can be 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm or 9 nm, etc.).

[0034] Preferably, the flavor solution in step (2) is a mixture of flavor and anhydrous ethanol.

[0035] Preferably, the mass ratio of the flavor to anhydrous ethanol is 1:(40-50), for example, it can be 1:41, 1:42, 1:43, 1:44, 1:45, 1:46, 1:47, 1:48 or 1:49, etc.

[0036] Preferably, the flavor includes sweet orange flavor.

[0037] Preferably, the specific steps of mixing in step (2) are:

[0038] The tea stem-based hydrothermal charcoal of step (1) is mixed with liquid paraffin at 60-70°C (for example, 61°C, 63°C, 65°C, 67°C or 69°C, etc.) for adsorption for 1-2h (for example, 1.1h, 1.3h, 1.5h, 1.7h or 1.9h, etc.), and then after cooling, the essence solution and the high thermal conductive nanosheets are added and mixed at 25-40°C (for example, 26°C, 28°C, 30°C, 32°C, 34°C, 36°C or 38°C, etc.) for 3-5h (for example, 3.2h, 3.5h, 3.8h, 4h, 4.2h, 4.5h or 4.8h, etc.).

[0039] Any specific point value within the above numerical range can be selected, and will not be described in detail here.

[0040] In a second aspect, the present invention provides a tea stem-based aroma granular material, which is prepared by the method described in the first aspect.

[0041] In a third aspect, the present invention provides a use of the tea stem-based aroma granular material as described in the second aspect in a cigarette filter material.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] (1) Compared with the traditional commercial porous carbon flavor loading material, the tea stem-based hydrothermal carbon flavor loading material prepared by the present invention has the same amount of flavor adsorption. After using the phase change material liquid paraffin and the high thermal conductivity material boron nitride, the room temperature storage stability of the flavor and the sustained release performance of the flavor are significantly improved. As an adsorbent, it can efficiently and quickly adsorb flavors and has broad application prospects.

[0044] (2) The present invention is based on ZnCl 2 As a catalyst, the hemicellulose in the tea stems is easily hydrolyzed during the hydrothermal process, so there is a relatively developed surface pore structure. After hydrothermal treatment, the material is mainly amorphous carbon with a large number of oxygen-containing functional groups on its surface, which can provide a large number of active sites for the adsorption of flavors.

[0045] (3) The present invention uses liquid paraffin with low viscosity and high stability in order to prevent excessive adsorption of the flavor inside the hydrothermal carbon pores, thereby facilitating its rapid release at 40-60°C. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 is a scanning electron microscope picture of the microscopic morphology of tea stem hydrothermal carbon prepared under different hydrothermal conditions in Examples 1-7 of the present invention, where ag in the picture corresponds to the particles of Examples 1-7 respectively;

[0047] Figure 2 1 and 2 are nitrogen absorption-desorption curves and pore size distribution diagrams of tea stem hydrothermal charcoal prepared in Examples 1 and 7-8 of the present invention, wherein a is the nitrogen absorption-desorption curve and b is the pore size distribution diagram. DETAILED DESCRIPTION

[0048] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only used to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0049] The raw materials used in the following embodiments can be used as long as they are purchased from regular dealers.

[0050] Example 1

[0051] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof comprises:

[0052] (1) The tea stems are crushed and then sieved into 50 mesh tea stem particles; the tea stem particles and water are added into a hot reaction kettle at a mass ratio of 1:10, and then a catalyst ZnCl is added. 2 (the amount added is 1% of the total amount of the reactants), the temperature is adjusted to 180°C, the speed is set to 200 rpm, the reaction is carried out for 60 minutes, and the reaction system is filtered after cooling to room temperature, and then fully washed with water, filtered, and dried at 100°C to obtain tea stem-based hydrothermal charcoal;

[0053] (2) Pour 1 g of tea stem-based hydrothermal charcoal into a weighing bottle, add 0.2 g of liquid paraffin (boiling point of 320°C, viscosity of 20 mPa·s at 40±5°C) into the weighing bottle and mix with the hydrothermal charcoal at a constant temperature of 65°C for adsorption for 1.5 h, cool to 30°C, add 2 g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol in a mass ratio of 1:49) and 0.1 g of boron nitride (sheet diameter of 1 μm and thickness of 5 nm), mix well and add to the weighing bottle, stir for 4 h to allow the tea stem-based hydrothermal charcoal to fully adsorb the flavor, then transfer the tea stem-based hydrothermal charcoal into a culture dish and air dry naturally to obtain the tea stem-based aroma-imparting granular material.

[0054] Example 2

[0055] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof comprises:

[0056] (1) The tea stems are crushed and then sieved to obtain 40 mesh tea stem particles; the tea stem particles and water are added into a hot reaction kettle at a mass ratio of 1:8, and then a catalyst ZnCl is added. 2 (the amount added is 0.8% of the total amount of the reactants), the temperature is adjusted to 200°C, the speed is set to 120rpm, the reaction is carried out for 150min, the reaction system is cooled to room temperature and filtered, then fully washed with water, filtered, and dried at 110°C to obtain tea stem-based hydrothermal charcoal;

[0057] (2) Pour 1 g of tea stem-based hydrothermal charcoal into a weighing bottle, add 0.4 g of liquid paraffin (boiling point of 320°C, viscosity of 25 mPa·s at 50±5°C) into the weighing bottle and mix with the hydrothermal charcoal at a constant temperature of 70°C for 2 h, cool to 25°C, add 1 g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol in a mass ratio of 1:45) and 0.2 g of boron nitride (sheet diameter of 0.5 μm and thickness of 10 nm), mix well and add to the weighing bottle, stir for 3 h to allow the tea stem-based hydrothermal charcoal to fully absorb the flavor, then transfer the tea stem-based hydrothermal charcoal into a culture dish and air dry naturally to obtain the tea stem-based aroma-imparting granular material.

[0058] Example 3

[0059] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof comprises:

[0060] (1) The tea stems are crushed and then sieved to obtain 60 mesh tea stem particles; the tea stem particles and water are added into a hot reaction kettle at a mass ratio of 1:12, and then a catalyst ZnCl is added. 2 (the amount added is 1.5% of the total amount of the reactants), the temperature is adjusted to 160°C, the speed is set to 300 rpm, the reaction is carried out for 90 minutes, and the reaction system is filtered after cooling to room temperature, and then fully washed with water, filtered, and dried at 100°C to obtain tea stem-based hydrothermal charcoal;

[0061] (2) Pour 1 g of tea stem-based hydrothermal charcoal into a weighing bottle, add 0.1 g of liquid paraffin (boiling point of 350°C, viscosity of 15 mPa·s at 30±5°C) into the weighing bottle and mix with the hydrothermal charcoal at a constant temperature of 60°C for adsorption for 1 h, cool to 35°C, add 3 g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol in a mass ratio of 1:40) and 0.15 g of boron nitride (sheet diameter of 2 μm and thickness of 8 nm), mix well, and add to the weighing bottle, stir for 5 h, so that the tea stem-based hydrothermal charcoal can fully adsorb the flavor, and then transfer the tea stem-based hydrothermal charcoal into a culture dish and air dry naturally to obtain the tea stem-based aroma-imparting granular material.

[0062] Example 4

[0063] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of embodiment 1 only in that the temperature of the hydrothermal reaction in step (1) is 210° C., and the remaining steps and process parameters are consistent with those of embodiment 1.

[0064] Example 5

[0065] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of embodiment 1 only in that the temperature of the hydrothermal reaction in step (1) is 140° C., and the remaining steps and process parameters are consistent with those of embodiment 1.

[0066] Example 6

[0067] This embodiment provides a tea stem-based aroma granular material, and its preparation method is different from that of Example 1 only in that the catalyst used in step (1) is sodium hydroxide solution (pH 10), and the amount of catalyst is kept unchanged, and the remaining steps and process parameters are consistent with Example 1.

[0068] Example 7

[0069] This embodiment provides a tea stem-based aroma granular material, and its preparation method is different from that of Example 1 only in that the catalyst used in step (1) is a hydrochloric acid solution (pH 1), and the amount of catalyst is kept unchanged, and the remaining steps and process parameters are consistent with Example 1.

[0070] Example 8

[0071] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of embodiment 1 only in that the catalyst used in step (1) is AlCl 3 , and keep the catalyst dosage unchanged, the remaining steps and process parameters are consistent with Example 1.

[0072] Example 9

[0073] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of embodiment 1 only in that the amount of liquid paraffin added in step (2) is 0.6 g, and the remaining steps and process parameters are consistent with those of embodiment 1.

[0074] Example 10

[0075] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of embodiment 1 only in that the amount of liquid paraffin added in step (2) is 0.05 g, and the remaining steps and process parameters are consistent with those of embodiment 1.

[0076] Embodiment 11

[0077] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of Example 1 only in that the amount of boron nitride added in step (2) is 0.25 g, and the remaining steps and process parameters are consistent with those of Example 1.

[0078] Example 12

[0079] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of embodiment 1 only in that the amount of boron nitride added in step (2) is 0.05 g, and the remaining steps and process parameters are consistent with those of embodiment 1.

[0080] Example 13

[0081] This embodiment provides a tea stem-based aroma granular material, and the preparation method thereof is different from that of embodiment 1 only in that boron nitride is replaced by an equal amount of aluminum nitride in step (2), and the remaining steps and process parameters are consistent with those of embodiment 1.

[0082] Comparative Example 1

[0083] This comparative example provides a tea stem-based aroma granular material, and the preparation method thereof is as follows:

[0084] (1) crushing tea stems and then sieving the tea stem particles to 50 mesh;

[0085] (2) Pour 1 g of tea stem particles into a weighing bottle, add 0.2 g of liquid paraffin (boiling point of 320°C, viscosity of 20 mPa·s at 40±5°C) into the weighing bottle and mix with the hydrothermal charcoal at a constant temperature of 65°C for adsorption for 1.5 h, then fully mix 2 g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol in a mass ratio of 1:49) with 0.1 g of boron nitride (sheet diameter of 1 μm and thickness of 5 nm) and add them to the weighing bottle, stir at 30°C for 4 h to allow the tea stem-based hydrothermal charcoal to fully adsorb the flavor, then transfer the tea stem-based hydrothermal charcoal into a culture dish and air-dry naturally to obtain the tea stem-based aroma-imparting granular material.

[0086] Comparative Example 2

[0087] This comparative example provides a tea stem-based aromatizing granular material, and the preparation method thereof differs from that of Example 1 only in that step (2) is: pouring 1 g of tea stem-based hydrothermal charcoal into a weighing bottle, and then fully mixing 2 g of essence solution (a mixture of sweet orange essence and anhydrous ethanol in a mass ratio of 1:49) and 0.1 g of boron nitride (with a sheet diameter of 1 μm and a thickness of 5 nm) and adding the mixture to the weighing bottle, stirring at 30° C. for 4 h to allow the tea stem-based hydrothermal charcoal to fully absorb the essence, and then transferring the tea stem-based hydrothermal charcoal into a culture dish and naturally air-drying to obtain the tea stem-based aromatizing granular material.

[0088] Comparative Example 3

[0089] The present comparative example provides a tea stem-based aromatizing granular material, the preparation method of which is different from that of Example 1 only in that step (2) is: pour 1 g of tea stem-based hydrothermal charcoal into a weighing bottle, add 0.2 g of liquid paraffin (boiling point of 320° C., viscosity of 20 mPa·s at 40±5° C.) into the weighing bottle and mix with the hydrothermal charcoal for adsorption at a constant temperature of 65° C. for 1.5 h, then add 2 g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol in a mass ratio of 1:49) into the weighing bottle, stir at 30° C. for 4 h to allow the tea stem-based hydrothermal charcoal to fully adsorb the flavor, then transfer the tea stem-based hydrothermal charcoal into a culture dish and allow it to dry naturally to obtain the tea stem-based aromatizing granular material.

[0090] Comparative Example 4

[0091] This comparative example provides a tea stem-based aromatized granular material, and its preparation method is different from that of Example 1 only in that step (2) is: pour 1 g of tea stem-based hydrothermal charcoal into a weighing bottle, add 2 g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol in a mass ratio of 1:49) into the weighing bottle, stir at 30°C for 4 h to allow the tea stem-based hydrothermal charcoal to fully absorb the flavor, and then transfer the tea stem-based hydrothermal charcoal into a culture dish and naturally air-dry to obtain the tea stem-based aromatized granular material.

[0092] Comparative Example 5

[0093] This comparative example provides a tea stem-based aroma granular material, and the preparation method thereof is as follows:

[0094] Weigh 1g and the specific surface area is about 1100m 2 / g of commercial activated carbon was poured into a weighing bottle, and 0.2mL of liquid paraffin (boiling point of 320℃, viscosity of 20mPa·s at 40±5℃) was added, and mixed and adsorbed at a constant temperature of 65℃ for 1.5h. Then 2mL of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol with a mass ratio of 1:49) and 0.1g of boron nitride (with a flake diameter of 1μm and a thickness of 5nm) were fully mixed and added to the volumetric bottle. The mixture was stirred thoroughly to allow the hydrothermal carbon to fully adsorb the flavor. The weighing bottle was then placed in a drying bottle. After 4h, the hydrothermal carbon in the weighing bottle was transferred to a petri dish for natural air drying. Finally, the flavor storage stability and release performance were tested.

[0095] Comparative Example 6

[0096] This comparative example provides a tea stem-based aromatizing granular material, the preparation method of which is different from that of Example 1 only in that the liquid paraffin in step (2) is replaced with an equal amount of solid paraffin (phase transition temperature is 50° C.), and the remaining steps and process parameters are consistent with those of Example 1.

[0097] Comparative Example 7

[0098] This comparative example provides a tea stem-based aroma granular material, the preparation method of which is different from that of Example 1 only in step (2), which is:

[0099] Pour 1 g of tea stem-based hydrothermal charcoal into a weighing bottle, add 0.2 g of liquid paraffin (boiling point of 320°C, viscosity of 20 mPa·s at 40±5°C), 2 g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol in a mass ratio of 1:49) and 0.1 g of boron nitride (sheet diameter of 1 μm, thickness of 5 nm), mix thoroughly, stir at 30°C for 4 h to allow the tea stem-based hydrothermal charcoal to fully absorb the flavor, and then transfer the tea stem-based hydrothermal charcoal into a culture dish and air-dry naturally to obtain the tea stem-based aroma-imparting granular material.

[0100] Test Example 1

[0101] The tea stem-based aroma granular materials obtained in Examples 1-13 and Comparative Examples 1-7 were characterized for their structures. The results are shown in Tables 1 and Figure 1-2 .

[0102] The microstructure and structure of the samples were characterized by scanning electron microscopy (SEM, Hitachi SU8220). The specific surface area and pore structure of the samples were tested using a fully automatic specific surface and porosity analyzer (Micromeritics ASAP2020 instrument).

[0103] Table 1

[0104] sample <![CDATA[Specific surface area / (m 2 / g)]]> <![CDATA[Pore volume / (cm 3 / g)]]> Average pore size / nm Example 1 6.8 0.051 13.85 Example 2 6.1 0.025 16.25 Example 3 4.6 0.029 12.07 Example 4 2.3 0.0042 8.03 Example 5 3.1 0.0063 12.31 Example 6 4.2 0.016 13.99 Example 7 3.7 0.0092 11.24 Example 8 3.2 0.024 11.05 Example 9 2.1 0.0035 10.24 Example 10 4.2 0.0086 11.43 Embodiment 11 6.4 0.056 13.46 Example 12 5.6 0.048 12.35 Embodiment 13 6.8 0.062 12.43 Comparative Example 1 5.6 0.0032 10.25 Comparative Example 2 4.9 0.065 13.56 Comparative Example 3 5.8 0.057 12.28 Comparative Example 4 5.5 0.049 12.23 Comparative Example 5 1100.2 0.60 10.26 Comparative Example 6 4.9 0.015 9.88 Comparative Example 7 5.3 0.034 10.65

[0105] like Figure 1As shown in Figures ac, the tea stem hydrothermal charcoal prepared in Examples 1-3 of the present invention uses ZnCl 2 As a catalyst, it has a catalytic activation effect during the hydrothermal reaction. The duct structure of the prepared tea stem hydrothermal charcoal is deformed, and there are tiny pores between the fibers, thus having a large number of structures, which is conducive to the diffusion and storage of flavors.

[0106] Depend on Figure 1 e It can be seen that at 210℃, some fibers of tea stem hydrothermal carbon were hydrolyzed, and then condensed and gathered on the surface of hydrothermal carbon;

[0107] Depend on Figure 1 f shows that when the reaction temperature is too low, the particles contain a large amount of fibrous filaments;

[0108] Depend on Figure 1 f and 1g show that since hemicellulose is more easily hydrolyzed under acidic and alkaline conditions, the volatile matter is seriously lost, resulting in a relatively rough fiber structure on the surface of the prepared tea stem hydrothermal charcoal.

[0109] The microstructures of samples at different temperatures are shown in Figure 1 (a-c), at 150℃ and 180℃, the overall morphology of the hydrothermal carbon is almost unchanged, and the fiber surface is relatively smooth, but the microscopic morphology of the samples at different times is as follows Figure 1 (d-e), which contains a large number of three-dimensional network structure fibrous filaments, but as the reaction time increases, some of the fibrous filaments are destroyed.

[0110] Depend on Figure 2 It can be seen that the particles of the present invention all show the characteristics of type III adsorption isotherm, indicating that the pores of the tea stem hydrothermal carbon prepared under different conditions are mainly macroporous structures.

[0111] As shown in Table 1, the specific surface areas of tea stem hydrothermal carbon prepared under different hydrothermal reaction conditions are all above 7 m 2 / g, among which, the specific surface areas of Examples 1-3 all reached 4.5m 2 / g or more, indicating that the tea stem hydrothermal carbon prepared by the present invention has more flavor adsorption sites. The hydrothermal temperature and catalyst both affect the specific surface area and pore volume of the particles.

[0112] Test Example 2

[0113] The flavor adsorption performance of the tea stem-based aroma granular materials obtained in Examples 1, 4-13 and Comparative Examples 1-7 was tested. The results are shown in Table 2.

[0114] The calculation method of adsorption efficiency is as follows: weigh 100g tea stem-based hydrothermal carbon, add some liquid paraffin and adsorb it at a constant temperature for 1h, then fully mix it with boron nitride and record the mass of tea stem-based hydrothermal carbon as m1 g, then add 100g of flavor solution (a mixture of sweet orange flavor and anhydrous ethanol with a mass ratio of 1:45), stir for 2min to allow the tea stem-based hydrothermal carbon to fully adsorb the flavor, put it in a fluidized bed dryer and dry it for 10min, record the tea stem-based hydrothermal carbon as m2 g, and the adsorption efficiency calculation formula is:

[0115] Release rate calculation method: Place m2 g of tea stem-based aroma granules in a brine moisture tester, measure the flavor release performance of the tea stem-based aroma granules at a certain temperature, and record the mass of the tea stem-based aroma granules at 600s as m3. The flavor release rate at 600s is

[0116] Stability calculation method: Place m2 g of tea stem-based aroma granules in a dryer. After seven days, weigh the mass of the tea stem-based aroma granules and record it as m4. The seven-day aroma loss rate is

[0117] Table 2

[0118]

[0119] As shown in Table 2, the tea stem-based aroma granular material prepared in Example 1 has an aroma release rate of more than 80% in 600 seconds and an aroma loss rate of no more than 25% in 7 days.

[0120] Compared with Example 1, Comparative Example 2 did not add phase change material liquid paraffin, and the tea stem-based aroma granular material had a well-developed pore structure, mostly macropores, and poor stability in adsorbing flavors, with a 7-day flavor loss rate as high as 84%;

[0121] Compared with Example 1, Comparative Example 3 does not add the thermal conductive material boron nitride, resulting in liquid paraffin blocking the macropores of the tea stem-based flavoring granular material, making it impossible to release the flavor under low temperature conditions. The flavor release rate in 600s is only 31%, and the flavor release performance is poor.

[0122] Compared with Example 1, Comparative Example 4 did not add phase change material liquid paraffin and thermal conductive material boron nitride, the flavor release rate in 600 seconds was only 43%, and the flavor loss rate in 7 days was as high as 74%, and the flavor release performance and stability performance were poor.

[0123] Compared with Example 1, Comparative Example 5 uses commercial activated carbon, which has a higher specific surface area and a more developed pore structure, which is not conducive to the storage stability of the flavor. The flavor loss rate in 7 days is as high as 71%.

[0124] Compared with Example 1, Comparative Example 6 uses solid paraffin with phase change properties. The solid paraffin has a larger viscosity and needs to be heated at a higher temperature to melt it before it can be mixed with the tea stem-based flavoring granular material, thus affecting the storage stability of the flavor.

[0125] Compared with Example 1, the liquid paraffin used in Comparative Example 7 was physically mixed with hydrothermal charcoal without an adsorption process, so the liquid paraffin did not play a role in assisting the adsorption of flavors, and blocked its pore structure, reducing the specific surface area, resulting in reduced adsorption performance.

[0126] Test Example 3 Sensory Evaluation

[0127] The particles obtained in Examples 1-13 and Comparative Examples 1-7 were added to cigarette filters at an addition amount of 15 mg / cigarette, and cigarettes without any other ingredients were used as control cigarettes for sensory evaluation.

[0128] Organize 7 tasters to evaluate and score the food according to the evaluation contents and criteria in Table 3-4. The sensory quality indicators are scored on a 100-point scale.

[0129] The sensory quality evaluation indicators are: smoke volume (referring to smoke concentration and consistency), aroma and fragrance, strength, harmony, irritation and taste (aftertaste); the specific definitions of the six sensory quality evaluation indicators are shown in Table 3, and the evaluation criteria of the six sensory quality evaluation indicators are shown in Table 4.

[0130] Table 3

[0131]

[0132]

[0133] Table 4

[0134]

[0135] The specific results are shown in Table 5:

[0136] Table 5

[0137]

[0138]

[0139] It can be seen from the data in Table 5 that after adding the tea stem-based flavoring granular material of the present invention, the tobacco aroma of the cigarette is stronger, fuller and softer, and the aftertaste in the mouth can be effectively improved.

[0140] It can be seen from Examples 4-5 that when the hydrothermal reaction temperature is too high or too low, the specific surface area of ​​the prepared particles is small, and thus the adsorption effect on the fragrance is poor;

[0141] It can be seen from Examples 6-8 that when the catalyst is not the ZnCl 2 When the particles are added to cigarettes, the pore volume of the particles is poor, and the sensory enhancement effect is also poor.

[0142] It can be seen from Examples 9-12 that the dosage of liquid paraffin and boron nitride will affect the aroma release effect in the particles, and further affect the sensory experience after being added to cigarettes.

[0143] It can be seen from Example 13 that when the high thermal conductivity nanosheet is boron nitride, the sensory experience of the cigarette is better after the prepared material is added to the cigarette.

[0144] The applicant declares that the present invention illustrates the preparation method of a tea stem-based aroma granular material of the present invention and its product and application through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0145] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0146] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A method for preparing tea stem-based aroma granular material, characterized in that: The preparation method comprises: (1) crushing tea stems and then subjecting them to a hydrothermal reaction with water to obtain tea stem-based hydrothermal charcoal; (2) Mixing the tea stem-based hydrothermal charcoal obtained in step (1) with liquid paraffin, essence solution, and high thermal conductivity nanosheets, and air-drying the mixture to obtain the tea stem-based aroma-imparting granular material.

2. The preparation method according to claim 1, characterized in that: After the crushing in step (1), the tea stems are sieved; Preferably, the mesh size of the sieving is 30-80 meshes.

3. The preparation method according to claim 1 or 2, characterized in that: The mass ratio of the tea stems to water in step (1) is 1:(8-15); Preferably, a catalyst is added during the hydrothermal reaction in step (1); Preferably, the catalyst is added in an amount of 0.5-2% of the total amount of water and tea stems; Preferably, the catalyst is a metal chloride; Preferably, the metal chloride comprises any one or a combination of at least two of FeCl3, AlCl3 or ZnCl2; Preferably, the metal chloride is ZnCl2.

4. The preparation method according to any one of claims 1 to 3, characterized in that The temperature of the hydrothermal reaction in step (1) is 150-200° C. and the time is 30-90 min; Preferably, the reaction is carried out under stirring; Preferably, the stirring speed is 150-300 rpm.

5. The preparation method according to any one of claims 1 to 4, characterized in that After the hydrothermal reaction in step (1), the reaction product is washed with water, filtered and dried; Preferably, the drying temperature is 100-120°C.

6. The preparation method according to any one of claims 1 to 5, characterized in that In step (2), the mass ratio of the tea stem-based hydrothermal charcoal to the liquid paraffin, the essence solution, and the high thermal conductivity nanosheet is 1:(0.1-0.5):(1-3):(0.1-0.2); Preferably, the boiling point of the liquid paraffin in step (2) is higher than 300°C, and the viscosity is 10-30 mPa·s at 20-60°C; Preferably, the high thermal conductivity nanosheet in step (2) is any one of boron nitride, aluminum nitride or silicon carbide, or a combination of at least two thereof; Preferably, the high thermal conductivity nanosheet is boron nitride; Preferably, the size of the high thermal conductive nanosheet in step (2) is 0.5-2 μm in diameter and 2-10 nm in thickness; Preferably, the flavor solution in step (2) is a mixture of flavor and anhydrous ethanol; Preferably, the mass ratio of the essence to anhydrous ethanol is 1:(40-50).

7. The preparation method according to any one of claims 1 to 6, characterized in that The specific steps of mixing in step (2) are: The tea stem-based hydrothermal carbon of step (1) is mixed with liquid paraffin at 60-70° C. for 1-2 hours, and then after cooling, the essence solution and the high thermal conductivity nanosheets are added and mixed at 25-40° C. for 3-5 hours.

8. The preparation method according to any one of claims 1 to 7, characterized in that The mixing temperature in step (2) is 25-40° C. and the mixing time is 3-5 h.

9. A tea stem-based aroma granular material, characterized in that: The tea stem-based aroma granular material is prepared by the method according to any one of claims 1 to 8.

10. Use of the tea stem-based aroma granular material as claimed in claim 9 in cigarette filter materials.

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