A flavor sheet for a heated cigarette and a method of manufacturing the same

Abstract

The application discloses a flavor sheet for heated cigarettes and a preparation method thereof. A coating liquid including a flavor raw material, a solvent and a sustained-release agent is uniformly coated on the surface of a base material, and microwave drying is performed, so that the flavor sheet is obtained; the microwave drying is multi-stage continuous drying, and the number of drying stages is 3-5; power density distribution of each stage of the microwave drying is according to a sine wave type distribution, and is not 0 at the same time. The sine wave type multi-stage microwave drying has the characteristics of rapidness, low temperature and low convection, realizes rapid drying of the flavor sheet, and effectively reduces the loss of aroma substances in the flavor sheet. The flavor sheet prepared based on the method fully retains rich aroma substances in the raw material, smoke is soft, smoke volume is large, and volatilization of the aroma substances can be realized at low-temperature heating.

Description

Technical Field

[0001] This invention relates to a non-combustible cigarette flavoring sheet, specifically to a flavoring sheet for heated cigarettes and its preparation method, belonging to the field of heated cigarette production technology. Background Technology

[0002] Heated cigarettes are a new type of tobacco product that uses a non-combustible heat source to heat tobacco raw materials or similar processed products to produce smoke. The heating temperature is between 180℃ and 300℃. Their characteristics are: firstly, they are smoked using a specific heating device, eliminating the need for ignition, thus significantly reducing the harmful substances such as tar and carbon monoxide produced during the combustion of traditional cigarettes. Secondly, the smoke emitted from heated cigarettes is more palatable to the public than that from traditional cigarettes, alleviating the conflict between smoking bans in public places and the demand for smoking among smokers. Therefore, as a new type of tobacco product with a flavor closest to traditional cigarettes, heated cigarettes have experienced rapid development in recent years.

[0003] Tobacco sheets, tobacco shreds, and flavored paper base materials are the core components of heated cigarettes, and the quality of the raw materials used in heated cigarettes directly affects the sensory quality of the new cigarettes.

[0004] Heated cigarette formulation ingredients (tobacco sheets, shredded tobacco, and flavoring paper base materials) can better showcase their quality and characteristics when heated at the smoking device temperature (180-250℃). However, the current drying process temperature (above 120℃) is not significantly different from the device heating temperature, leading to substantial loss of aroma components during the drying process. Therefore, researching and developing rapid drying technology for heated cigarette formulation ingredients to reduce the baking intensity and aroma loss during the process is of great significance for further improving the sensory quality of heated cigarette products and maximizing their quality and style advantages. Summary of the Invention

[0005] To address the problems existing in the prior art, the first objective of this invention is to provide a flavoring sheet for heated cigarettes. This flavoring sheet is based on a low-temperature, rapid drying process, which fully preserves the rich aroma-producing substances in the raw materials, produces a mild smoke, and generates a large amount of smoke. The aroma-producing substances can be volatilized under low-temperature heating.

[0006] The second objective of this invention is to provide a method for preparing flavoring flakes for heated cigarettes. This method uses sinusoidal multi-segment microwave heating to achieve rapid drying while maximizing the retention of aroma-producing substances in the raw materials. The microwave heating method used in this invention effectively solves the problems of deformation, bubbling, and cracking of raw materials under the influence of high-power microwaves. Furthermore, through moisture-proof treatment, the technical objective of stabilizing the aroma of the flavoring flakes and ensuring long-term preservation is achieved.

[0007] To achieve the above-mentioned technical objectives, the present invention provides a method for preparing flavoring sheets for heated cigarettes, wherein a coating liquid including flavoring raw materials, solvents and slow-release agents is uniformly coated on the surface of a base material, and then dried by microwave. The microwave drying is a multi-stage continuous drying, with 3 to 5 drying stages. The power density distribution of each stage of the microwave drying follows a sinusoidal waveform and is not simultaneously 0. The power density of each stage of the microwave drying is 0 to 35 kW / m².

[0008] The preparation method provided by this invention employs a sinusoidal multi-segment microwave drying process, which not only achieves rapid drying of the flavoring tablets but also effectively reduces the loss of aroma-producing substances in the flavoring tablets. The microwave drying process uses sinusoidal power control along the feeding direction to prevent heat buildup at the tips of the flavoring tablets and decomposition of volatile aroma-producing substances caused by single power conditions. Furthermore, the microwave drying process uses a low power density, which not only effectively reduces energy loss during drying but also effectively solves the problems of deformation, bubbling, and cracking of raw materials under the influence of high-power microwaves.

[0009] As a preferred embodiment, the preparation method further includes a moisture-proof post-treatment process.

[0010] As a preferred embodiment, the post-moisture treatment process involves drying the spice flakes with hot air.

[0011] As a preferred embodiment, the hot air drying conditions are: temperature 40–60°C, feed rate 3–6 m / min, and drying time 1–6 min. The hot air drying process parameters must be strictly followed. If the temperature is too high, it will cause the loss of aroma compounds, resulting in weak smoke and a poor sensory experience; if the temperature is too low, it will not be able to reduce the moisture mixed in with the air, causing the flavoring chips to become damp again and reducing shelf life. The feed rate ensures that all flavoring chips are uniformly treated with moisture-proofing, preventing heat accumulation or dampness.

[0012] As a preferred embodiment, the solvent is at least one selected from water, ethanol, glycerol, propylene glycol, and caprylic / capric glyceride.

[0013] As a preferred embodiment, the sustained-release agent is at least one of carboxymethyl cellulose, hydroxypropyl methyl cellulose, and polyanionic cellulose, and the concentration of the sustained-release agent is between 5% and 15%.

[0014] As a preferred embodiment, the base material is at least one of flavored paper base material, tobacco sheet, and tobacco shreds.

[0015] As a preferred embodiment, the moisture content of the scented paper base material is 70-90%.

[0016] As a preferred embodiment, the moisture content of the tobacco sheet is 60-80%.

[0017] As a preferred embodiment, the moisture content of the tobacco shreds is 30-40%.

[0018] As a preferred embodiment, the coating liquid thickness on the surface of the substrate material is as follows: 0.3–1.5 mm for tobacco sheet surface, 1–2 mm for tobacco shred surface, and 0.3–1 mm for flavored paper base material surface. The thickness of the coating liquid directly affects the drying time; the thicker the coating liquid, the longer the drying time to reach the required moisture content.

[0019] As a preferred embodiment, the microwave drying process consists of three segments, with each segment exhibiting a power density distribution that is monotonically increasing, monotonically decreasing, increasing then decreasing, or decreasing then increasing.

[0020] As a preferred embodiment, the drying time for each segment of the microwave drying process is 2 to 6 minutes, and the transmission rate is 3 to 6 m / min.

[0021] The number of microwave drying stages and the power density distribution play a crucial role in the flavor profile of flavored flakes. For flavored flakes based on tobacco sheets or shredded tobacco, a monotonic power density distribution can further enhance the roasted, dried, and charred aromas of the flavored flakes, while highlighting the original plant aroma of the tobacco itself. For flavored paper-based materials, a non-monotonic power density distribution can enhance the burst of aroma, resulting in a complex and rich fragrance. Therefore, the microwave drying process parameters must be strictly performed within the range provided by this invention to maximize the retention and presentation of each aroma-producing substance while ensuring rapid drying.

[0022] As a preferred embodiment, the microwave power of each stage of the microwave drying process is infinitely adjustable, controlled by a combination of 1 to 16 microwave generators. Compared to the traditional stepped microwave power setting, this invention uses multiple infinitely powerful microwave generators to achieve a sinusoidal distribution of microwave power, effectively improving the precision and sensitivity of microwave control, significantly increasing the utilization rate of microwave energy for liquid-phase drying, and reducing the rapid accumulation of microwave energy that leads to the volatilization of aroma compounds and heat buildup in the fragrance chips.

[0023] The present invention also provides a flavoring sheet for heating cigarettes, obtained by any of the preparation methods described above, wherein the flavoring sheet has a moisture content of 9-13%.

[0024] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0025] 1) The flavoring sheet for heated cigarettes provided by the present invention is based on a low-temperature, rapid drying process, which fully preserves the rich aroma substances in the raw materials, produces a mild smoke, and produces a large amount of smoke. The aroma substances can be volatilized under low-temperature heating.

[0026] 2) In the method for preparing spice flakes provided by this invention, the sinusoidal multi-segment microwave drying method used in this invention has the characteristics of being fast, low temperature, and low convection. It not only achieves rapid drying of spice flakes, but also effectively reduces the loss of aroma substances in spice flakes. The microwave drying process uses sinusoidal power control along the feeding direction to prevent tip heat accumulation and decomposition of volatile aroma substances caused by single power conditions. Furthermore, the power density used in this microwave drying is low, which not only effectively reduces energy loss during drying, but also effectively solves the problems of deformation, bubbling, and cracking of raw materials under the influence of high-power microwaves.

[0027] 3) In the technical solution provided by the present invention, the additional moisture-proof treatment after microwave drying can maximize the preservation of the aroma quality of heated cigarettes or improve the quality of certain specific aroma types, improve energy utilization, dry at a lower ambient temperature, reduce the loss of volatile substances, and achieve uniform and rapid drying, thereby improving the quality of raw materials for heated cigarette formulations. Attached Figure Description

[0028] Figure 1 The GC-MS analysis results of the flavoring tablets obtained in Example 4 and Comparative Example 1 of this invention are shown in the following figures;

[0029] Figure 2 This is a photograph of the spice tablets obtained in Comparative Example 2 of the present invention.

[0030] Figure 3 This is a photograph of the spice slices obtained in Example 4 of the present invention. Detailed Implementation

[0031] The technical solutions of the present invention will be described in detail below with reference to the embodiments. The following embodiments are merely exemplary and can only be used to explain and illustrate the technical solutions of this embodiment, and should not be construed as limiting the technical solutions of this application.

[0032] Example 1

[0033] Yunnan Kunming C2F tobacco flakes were rehydrated to a moisture content of 35% and then shredded. The shreds were evenly spread on a conveyor belt and coated with a coating solution. The composition of the coating solution is shown in Table 1. The coating thickness was 1 mm. After coating, the tobacco entered a microwave drying section. The microwave power densities used in the front, middle, and rear sections were 9 kW / m², 17 kW / m², and 34 kW / m², respectively. The drying time was 3 min, and the conveyor speed was 5 m / min. The moisture content of the tobacco shreds at the microwave drying section exit was 18%. Subsequently, the tobacco entered a hot air drying section at a hot air temperature of 60℃ for 3 min, with a conveyor speed of 5 m / min. The moisture content of the material at the exit was 12.1%. Sensory evaluation by seven people revealed that the tobacco shreds treated in the above steps, compared to tobacco shreds treated with conventional baking, had a stronger hay and roasted aroma, a greater aroma intensity, and a richer, more robust aroma.

[0034] Table 1. Coating liquid in Example 1

[0035]

[0036]

[0037] Example 2

[0038] The coating thickness of the scented paper base material was controlled at 0.5 mm. The composition of the coating solution is shown in Table 2. After coating, the microwave power densities used in the three stages of microwave drying were 6 kW / m², 16 kW / m², and 30 kW / m², respectively. The drying time was 3 min, and the transmission speed was 5 m / min. The moisture content of the material at the microwave drying stage exit was 20%. Subsequently, it entered the hot air drying stage at a hot air temperature of 45℃ for 3 min, with a transmission speed of 5 m / min. The moisture content of the material at the exit was 12.1%. After sensory evaluation by seven people, it was found that the scented paper base material treated in the above steps had a richer aroma and a more complete preservation of the aroma profile compared to the material dried in a conventional oven.

[0039] Table 2. Coating liquid in Example 2

[0040] Homemade Flavoring 2％ HPMC 8％ ethanol 60％ water 30％

[0041] Example 3

[0042] The coating thickness of the scented paper base material was controlled at 1 mm. The composition of the coating solution is shown in Table 3. After coating, the microwave power densities used in the three stages of microwave drying were 20 kW / m², 17 kW / m², and 25 kW / m², respectively. The drying time was 5 min, and the transmission speed was 3 m / min. The moisture content of the material at the microwave drying stage exit was 23%. Subsequently, it entered the hot air drying stage at a hot air temperature of 50℃ for 5 min, with a transmission speed of 3 m / min. The moisture content of the material at the exit was 11.5%. After sensory evaluation by seven people, it was found that the scented paper base material treated in the above steps had a richer aroma and a more complete preservation of the aroma profile compared to the material dried in a conventional oven.

[0043] Table 3. Coating liquid in Example 3

[0044]

[0045]

[0046] Example 4

[0047] The coating thickness of the papermaking sheet was controlled at 1 mm. The composition of the coating solution was as shown in Table 4. After coating, the microwave power densities used in the three stages of microwave drying were 15 kW / m², 10 kW / m², and 25 kW / m², respectively. The drying time was 5 min, and the transmission speed was 3 m / min. The moisture content of the sheet at the exit of the microwave drying stage was 20%. Subsequently, it entered the hot air drying stage. The hot air temperature was 60℃, the drying time was 5 min, and the transmission speed was 3 m / min. The moisture content of the material at the exit was 9.5%. After sensory evaluation by 7 people, it was found that the tobacco sheet treated by the above steps had a more prominent hay and smoky aroma, and the natural tobacco aroma was more pronounced compared to the sheet dried by conventional hot steel plate drying.

[0048] Table 4. Coating liquid in Example 4

[0049] Homemade Flavoring 2％ CMC 8％ glycerin 20％ ethanol 40％ water 30％

[0050] Comparative Example 1

[0051] The preparation process of this comparative example is exactly the same as that of Example 4, except that an oven is used instead of microwave drying. The oven hot air drying temperature is 80°C, the drying time is 5 min, and the moisture content of the outlet material is 9.5%.

[0052] Comparative Example 2

[0053] The preparation process of this comparative example is exactly the same as that of Example 4, except that single-power microwave drying is used, with a microwave power of 25 kW / m², an oven hot air drying temperature of 80°C, a drying time of 5 min, and an outlet material moisture content of 9.5%.

[0054] GC-MS analysis was performed on the flavoring tablets obtained in Example 4 and Comparative Example 1, and the results are as follows: Figure 1 As shown, the results indicate that the content of aroma-producing chemicals such as neophytadiene, 6-hydroxy-7-methoxycoumarin, nicotine, palmitic acid, methyl linoleate, and dihydroactinolone in the samples dried by the combined microwave and hot air drying method is generally higher than that in the oven-dried samples. The combined microwave and hot air drying method plays a crucial role in ensuring the distinctive flavor of heated cigarettes.

[0055] Regarding the above embodiment 4 ( Figure 3 The obtained spice flakes and comparative example 2 ( Figure 2 The comparison of the obtained spice tablets clearly shows that the spice tablets of Comparative Example 2 exhibit bubbling, while the spice tablets of Example 4 have a smooth and flat surface coating without bubbling. Furthermore, sensory evaluation revealed that the aroma release intensity and uniformity of the spice tablets of Example 2 were worse than those of Example 4.

Claims

1. A method for preparing flavoring flakes for heated cigarettes, characterized in that: A coating liquid, including fragrance raw materials, solvents, and slow-release agents, is uniformly coated onto the surface of a substrate material and then microwave-dried to obtain the final product. The microwave drying is a multi-stage continuous drying process with 3 to 5 stages. The power density distribution of each stage of the microwave drying process follows a sinusoidal waveform and is not simultaneously zero. The power density of each stage of the microwave drying process ranges from 0 to 35 kW / m². 2 ; The microwave drying process consists of three segments, and the power density distribution of each segment is one of the following: monotonically increasing, monotonically decreasing, increasing first and then decreasing, or decreasing first and then increasing. The microwave power of each section of the microwave drying process is infinitely adjustable and controlled by a combination of 1 to 16 microwave generators. The preparation method further includes a moisture-proof post-treatment process; the moisture-proof post-treatment process is: hot air drying of the spice slices; The hot air drying conditions are: temperature 40~60℃, feeding rate 3~6m / min, and drying time 1~6min; The solvent is at least one selected from water, ethanol, glycerol, propylene glycol, and caprylic / capric glyceride; the sustained-release agent is at least one selected from carboxymethyl cellulose, hydroxypropyl methyl cellulose, and polyanionic cellulose. The base material is at least one of flavored paper base material and tobacco sheet; The moisture content of the flavored paper base material is 70-90%; the moisture content of the tobacco sheet is 60-80%. The coating liquid thickness on the surface of the substrate material is: 0.3~1.5mm for the tobacco sheet surface and 0.3~1mm for the flavored paper base material surface; The drying time for each segment of the microwave drying process is 2-6 minutes, and the transmission rate is 3-6 m / min.

2. A flavoring tablet for heating cigarettes, characterized in that: The spice tablets obtained by the preparation method according to claim 1 have a moisture content of 9-13%.

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