Preparation method of reconstituted tobacco substrate as well as product and application of reconstituted tobacco substrate

Abstract

The invention provides a preparation method of a reconstituted tobacco substrate as well as a product and application thereof. The preparation method comprises the following steps: (1) soaking a tobacco stem raw material in deionized water, and then defibering and pulping to obtain tobacco stem pulp; (2) mixing the tobacco stem pulp, tobacco pulp, wood pulp, calcium carbonate and an adhesive to obtain mixed pulp, and then making sheets to obtain a substrate; according to the method, the reconstituted tobacco base material which is rich in pore channel structure and high in pyrolysis and combustion performance is successfully prepared. Meanwhile, after the prepared reconstituted tobacco base material is coated with coating liquid and dried, the reconstituted tobacco product with excellent sensory quality is prepared, and possibility is provided for efficient utilization of tobacco waste resources, reduction of environmental pollution and preparation of the high-performance reconstituted tobacco product.

Description

Technical Field

[0001] The invention belongs to the technical field of tobacco, and in particular relates to a preparation method of a reconstituted tobacco leaf substrate, a product thereof and an application thereof. Background Art

[0002] my country is the world's largest tobacco grower, producer and consumer. According to the China Statistical Yearbook (2023), by the end of 2023, my country's tobacco planting area exceeded 1,044,000 hectares, and tobacco leaf production reached 218.8wt. Based on the current 60% waste ratio in tobacco harvesting and processing, the amount of tobacco waste generated that year was as high as 131.28wt.

[0003] Reconstituted tobacco refers to waste products such as discarded tobacco stems, tobacco dust, fragments and ash sticks produced during the production and processing of tobacco leaves, which are used as raw materials and are made into sheet or filament products that can be used as cigarette fillers through processes such as extraction, pulping, coating, drying and cutting. Compared with natural tobacco leaves, reconstituted tobacco leaves also have significant advantages in product consistency, controllability and sensory improvement. In terms of product consistency, natural tobacco leaves are limited by natural growth conditions, and tobacco leaves from different parts and production areas have large differences in thickness, density and uniformity of chemical composition. Reconstituted tobacco leaves can achieve precise control of products through processes such as pulping, papermaking and coating during the production process.

[0004] Although reconstituted tobacco has been widely used in the production process of cigarette products, there are still many problems in its practical application. Since the fragmented raw materials in reconstituted tobacco products are strictly limited by the product formula and the variable space is narrow, the present invention uses four different types of tobacco stem raw materials, namely, super long stems, long stems, short stems and stem heads, and optimizes them according to a certain proportion to obtain a reconstituted tobacco substrate with good pyrolysis performance, and analyzes the key factors affecting its pyrolysis performance through SEM and TG characterization technology. Finally, the optimal proportion of different types of tobacco stems is determined through sensory evaluation. Summary of the invention

[0005] In view of the deficiencies of the prior art, the object of the present invention is to provide a method for preparing a reconstituted tobacco leaf substrate and its product and application.

[0006] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0007] In a first aspect, the present invention provides a method for preparing a reconstituted tobacco leaf substrate, the method comprising:

[0008] (1) soaking tobacco stem raw materials in deionized water, and then dispersing and pulping to obtain tobacco stem slurry;

[0009] (2) Tobacco stem slurry, tobacco pulp, wood pulp, calcium carbonate and an adhesive are mixed to obtain a mixed slurry, which is then sheeted to obtain a base sheet.

[0010] The preparation method provided by the present invention can improve the structure of the reconstituted tobacco leaf substrate itself, and this improvement plays an important role in improving its pore structure, pyrolysis and combustion performance, and loading more aroma substances. At the same time, the improvement of these properties is also of great significance for realizing the functionalization of reconstituted tobacco leaves.

[0011] Preferably, the mass ratio of the tobacco stem raw material to deionized water in step (1) is 1:(5-15), for example, it can be 1:6, 1:7, 1:8, 1:9, 1:10, 1:11, 1:12, 1:13 or 1:14, etc.

[0012] Preferably, the tobacco stem raw material includes any one of extra-long stems, long stems, short stems or stem heads, or a combination of at least two of them; the length of the extra-long stems is greater than or equal to 40 mm (for example, it can be 45 mm, 50 mm, 55 mm, 60 mm or 70 mm, etc.); the length of the long stems is greater than or equal to 20 mm and less than 40 mm (for example, it can be 21 mm, 23 mm, 25 mm, 28 mm, 30 mm, 32 mm, 35 mm, 37 mm or 39 mm, etc.); the length of the short stems is less than 20 mm (for example, it can be 2 mm, 5 mm, 8 mm, 10 mm, 12 mm, 15 mm, 17 mm or 19 mm, etc.).

[0013] Preferably, the tobacco stem raw material is a combination of extra-long stems, long stems, short stems and stem heads.

[0014] Preferably, the mass ratio of the extra-long stem, long stem, short stem and stem head is (3-5):(3-4):(1-2):(1-2).

[0015] The present invention not only enriches the pore structure of the reconstituted tobacco substrate by optimizing the ratio of different types of tobacco stem raw materials in the reconstituted tobacco, but also improves the pyrolysis and combustion performance of the reconstituted tobacco substrate, ultimately making the product exhibit good sensory quality.

[0016] Wherein "3-5" can be 3.1, 3.3, 3.5, 3.7, 3.9, 4, 4.1, 4.3, 4.5, 4.7 or 4.9, etc.;

[0017] "3-4" can be 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8 or 3.9, etc.;

[0018] The first "1-2" can be 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8 or 1.9, etc.;

[0019] The second "1-2" can be 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8 or 1.9, etc.

[0020] Preferably, the soaking temperature in step (1) is 60-70°C (for example, 61°C, 63°C, 65°C, 67°C or 69°C, etc.), and the soaking time is 20-40min (for example, 22min, 25min, 28min, 30min, 32min, 35min or 38min, etc.).

[0021] Preferably, solid-liquid separation is performed after the soaking.

[0022] Preferably, the specific steps of the decongestion in step (1) are:

[0023] The tobacco stem raw material after solid-liquid separation is placed in a deflagrator, deionized water is added, and the flocculent slurry is obtained after stirring.

[0024] Preferably, the amount of deionized water added is 1-5 times the weight of the tobacco stem raw material, for example, it can be 1.5 times, 2 times, 2.5 times, 3 times, 3.5 times, 4 times or 4.5 times, etc.

[0025] Preferably, the stirring time is 8-20 min, for example, 9 min, 10 min, 12 min, 14 min, 16 min or 18 min.

[0026] Preferably, the specific steps of pulping in step (1) are:

[0027] The deflaked pulp is introduced into the PFI mill and the tobacco stem pulp is obtained after pulping.

[0028] Preferably, the grinding tooth spacing of the PFI mill is 1-1.5 mm, for example, 1.1 mm, 1.2 mm, 1.3 mm or 1.4 mm.

[0029] Preferably, the number of revolutions of the beating treatment is 8000-15000 rpm, for example, 9000 rpm, 10000 rpm, 11000 rpm, 12000 rpm, 13000 rpm or 14000 rpm.

[0030] Preferably, the beating degree of the tobacco stem slurry is 65-70°SR, for example, it may be 66°SR, 67°SR, 68°SR, 69°SR or 70°SR.

[0031] Preferably, the absolute dry mass ratio of the tobacco stem slurry, tobacco pulp, wood pulp and calcium carbonate in step (2) is (3-7):(2-5):(0.1-1):(1-2).

[0032] Wherein "3-7" can be 3.2, 3.5, 3.8, 4, 4.2, 4.5, 4.8, 5, 5.2, 5.5, 5.8, 6, 6.2, 6.5 or 6.8, etc.;

[0033] “2-5” can be 2.2, 2.5, 2.8, 3, 3.2, 3.5, 3.8, 4, 4.2, 4.5 or 4.8, etc.;

[0034] “0.1-1” can be 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8 or 0.9, etc.;

[0035] “1-2” can be 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8 or 1.9, etc.

[0036] Preferably, the amount of the adhesive added is 15-25% of the total amount of the tobacco stem slurry, tobacco pulp, wood pulp and calcium carbonate, for example, 16%, 18%, 20%, 22% or 24%.

[0037] Preferably, the adhesive comprises any one of guar gum, sodium carboxymethyl cellulose, xanthan gum or gelatin, or a combination of at least two of them.

[0038] Preferably, the raw materials for preparing the tobacco pulp include any one of tobacco leaves, tobacco shreds or tobacco foam, or a combination of at least two of them;

[0039] Preferably, the beating degree of the tobacco pulp is 60-65°SR, for example, it may be 61°SR, 62°SR, 63°SR, 64°SR or 65°SR.

[0040] Preferably, the concentration of the wood pulp is 3-8%, for example, 4%, 5%, 6%, 7% or 8%.

[0041] Preferably, the weight of the reconstituted tobacco leaf substrate is 55-60 g / m 2 (For example, it can be 56g / m 2 , 57g / m 2 , 58g / m 2 , 59g / m 2 or 60g / m 2 etc.), the water content is 10-15% (for example, it can be 11%, 12%, 13%, 14% or 15%, etc.).

[0042] Any specific point value within the above numerical range can be selected, and will not be described in detail here.

[0043] In a second aspect, the present invention provides a reconstituted tobacco leaf substrate, which is prepared by the method described in the first aspect.

[0044] In a third aspect, the present invention provides a use of the reconstituted tobacco base sheet as described in the second aspect in preparing reconstituted tobacco.

[0045] Preferably, the method for preparing the reconstituted tobacco comprises:

[0046] The coating liquid is coated on both sides of the reconstituted tobacco leaf base sheet, and the reconstituted tobacco leaf is obtained after drying.

[0047] Preferably, the coating liquid comprises tobacco extract and / or plant extract.

[0048] Preferably, the coating amount of the coating liquid is 35-50% of the total weight of the reconstituted tobacco leaf substrate, for example, it can be 36%, 38%, 40%, 42%, 44%, 46% or 48%.

[0049] Any specific point value within the above numerical range can be selected, and will not be described in detail here.

[0050] Compared with the prior art, the present invention has the following beneficial effects:

[0051] The method of the present invention successfully produces a reconstituted tobacco leaf substrate with rich pore structure, high pyrolysis and combustion performance. At the same time, after the prepared reconstituted tobacco leaf substrate is coated with a coating liquid and dried, a reconstituted tobacco leaf product with excellent sensory quality is obtained, which provides the possibility of realizing efficient utilization of tobacco waste resources, reducing environmental pollution, and preparing high-performance reconstituted tobacco leaf products. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] Figure 1 1 is a surface morphology diagram of the substrate of Example 1 and Examples 4-6;

[0053] Figure 2 It is a picture of the epidermis of long stalk, extra long stalk, short stalk and stalk head;

[0054] Figure 3 These are cross-sectional morphological images of long stalks, extra-long stalks, short stalks, and stalk heads;

[0055] Figure 4 It is a longitudinal section of long stalk, extra long stalk, short stalk and stalk head;

[0056] Figure 5 It is the thermogravimetric analysis diagram of the substrate samples of Example 1 and Examples 4-6. DETAILED DESCRIPTION

[0057] 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.

[0058] The tobacco stems, tobacco pulp and wood pulp used in the following examples were provided by Jiangsu Xinyuan Tobacco Sheet Co., Ltd.; light calcium carbonate was purchased from Sichuan Yibang Technology Co., Ltd.; guar gum was purchased from Kunshan Jingkun Oilfield Chemical Technology Development Co., Ltd.

[0059] Example 1

[0060] This embodiment provides a method for preparing a reconstituted tobacco leaf substrate, the method comprising:

[0061] (1) Weighing 100 g of dried tobacco stem raw material (the tobacco stem is a combination of extra-long stems, long stems, short stems and stem heads in a mass ratio of 4:4:1:1), placing it in 800 mL of deionized water, soaking it in a 65° C. water bath for 30 min, and filtering it with a filter to achieve solid-liquid separation;

[0062] (2) The separated solid is placed in a fiber standard deflaking machine, 300 mL of water is added for deflaking, and the deflaked slurry is obtained after stirring;

[0063] (3) placing the slurry from step (2) in a PFI mill, setting the grinding tooth spacing to 1.25 mm, setting the number of revolutions to 10,000, and obtaining a tobacco stem slurry having a beating degree of 70° SR after beating;

[0064] (4) adding guar gum (additional 0.4 g) and mixing the prepared tobacco stem slurry, tobacco chip slurry (beating degree of 65°SR), wood pulp (pulp concentration of 5.0%) and light calcium carbonate in a ratio of 5.5:3:1:1.5 (the above ratios are calculated based on the absolute dry weight of the materials, with a total weight of 2 g), and then uniformly mixing to prepare a mixed slurry;

[0065] (5) The prepared mixed slurry is used to form a substrate using a fast Kayser sheet forming machine. The substrate is named JP1.

[0066] Example 2

[0067] This embodiment provides a method for preparing a reconstituted tobacco leaf substrate, the method comprising:

[0068] (1) Weighing 100 g of dried tobacco stem raw material (the tobacco stem is a combination of extra-long stems, long stems, short stems and stem heads in a mass ratio of 3:4:1:2), placing it in 800 mL of deionized water, soaking it in a 70° C. water bath for 20 min, and filtering it with a filter to achieve solid-liquid separation;

[0069] (2) The separated solid is placed in a fiber standard deflaking machine, 400 mL of water is added for deflaking, and the deflaked slurry is obtained after stirring;

[0070] (3) placing the slurry from step (2) in a PFI mill, setting the grinding tooth spacing to 1 mm, setting the number of revolutions to 12,000, and obtaining a tobacco stem slurry having a beating degree of 65° SR after beating;

[0071] (4) adding the prepared tobacco stem slurry, tobacco chip slurry (beating degree of 63°SR), wood pulp (pulp concentration of 5.0%) and light calcium carbonate in a ratio of 5:5:0.5:2 (the above ratios are calculated based on the absolute dry weight of the materials, with a total weight of 2 g), and then adding guar gum (additional 0.5 g) and uniformly mixing to prepare a mixed slurry;

[0072] (5) The prepared mixed slurry is used to form a substrate using a fast Kayser sheet machine.

[0073] Example 3

[0074] This embodiment provides a method for preparing a reconstituted tobacco leaf substrate, the method comprising:

[0075] (1) Weighing 100 g of dried tobacco stem raw material (the tobacco stem is a combination of extra-long stems, long stems, short stems and stem heads in a mass ratio of 5:3:2:1), placing it in 800 mL of deionized water, soaking it in a 60° C. water bath for 40 min, and filtering it with a filter to achieve solid-liquid separation;

[0076] (2) The separated solid is placed in a fiber standard deflaking machine, 500 mL of water is added for deflaking, and the deflaked slurry is obtained after stirring;

[0077] (3) placing the slurry from step (2) in a PFI mill, setting the grinding tooth spacing to 1.5 mm, setting the number of revolutions to 10,000, and obtaining a tobacco stem slurry having a beating degree of 68° SR after beating;

[0078] (4) the prepared tobacco stem slurry, the tobacco chip slurry (beating degree of 60°SR), the wood pulp (pulp concentration of 5.0%) and the light calcium carbonate are mixed in a ratio of 7:3:1:1 (the above ratios are calculated based on the absolute dry weight of the materials, and the total weight is 2 g), and then guar gum (additional 0.5 g) is added and uniformly mixed to prepare a mixed slurry;

[0079] (5) The prepared mixed slurry is used to form a substrate using a fast Kayser sheet machine.

[0080] Example 4

[0081] The present embodiment provides a method for preparing a reconstituted tobacco leaf substrate, which differs from the embodiment 1 only in that, in step (1), the ratio of super-long stems, long stems, short stems and stem heads in the tobacco stem raw material is 3:2:2:2, and the total amount of tobacco stem raw material is kept unchanged, and the remaining steps are consistent with the embodiment 1. The substrate finally obtained is named JP2.

[0082] Example 5

[0083] The present embodiment provides a method for preparing a reconstituted tobacco leaf substrate, which differs from the embodiment 1 only in that in step (1), the ratio of super-long stems, long stems, short stems and stem heads in the tobacco stem raw material is 2:4:3:3, and the total amount of tobacco stem raw material is kept unchanged, and the remaining steps are consistent with the embodiment 1. The substrate finally obtained is named JP3.

[0084] Example 6

[0085] This embodiment provides a method for preparing a reconstituted tobacco leaf substrate, which differs from Embodiment 1 only in that, in step (1), the ratio of super-long stems, long stems, short stems and stem heads in the tobacco stem raw material is 6:1:3:3, and the total amount of tobacco stem raw material is kept unchanged, and the remaining steps are consistent with Embodiment 1. The substrate finally obtained is named JP4.

[0086] Comparative Example 1

[0087] This comparative example provides a method for preparing a reconstituted tobacco leaf substrate, the preparation method differing from that of Example 1 only in that step (4) is:

[0088] The prepared tobacco stem pulp, wood pulp (pulp concentration of 5.0%) and light calcium carbonate are mixed at a ratio of 5.5:1:1.5 (the above ratio is calculated based on the absolute dry weight of the materials, and the total weight is 2g), and then guar gum (additional 0.4g) is added and uniformly mixed to prepare a mixed slurry;

[0089] The remaining steps are consistent with those in Example 1.

[0090] Comparative Example 2

[0091] This comparative example provides a method for preparing a reconstituted tobacco leaf substrate, the preparation method differing from that of Example 1 only in that step (4) is:

[0092] The prepared tobacco stem slurry, the chip tobacco slurry (beating degree of 65°SR) and the light calcium carbonate are mixed in a ratio of 5.5:3:1.5 (the above ratio is calculated based on the absolute dry weight of the materials, and the total weight is 2g), and then guar gum (additional 0.4g) is added and uniformly mixed to prepare a mixed slurry;

[0093] The remaining steps are consistent with those in Example 1.

[0094] Comparative Example 3

[0095] This comparative example provides a method for preparing a reconstituted tobacco leaf substrate, the preparation method comprising:

[0096] (1) Weighing 100 g of dried tobacco stem raw material (the tobacco stem is a combination of extra-long stems, long stems, short stems and stem heads in a mass ratio of 4:3.5:1.5:1.5), placing it in 800 mL of deionized water, soaking it in a 65° C. water bath for 30 min, and filtering it with a filter to achieve solid-liquid separation;

[0097] (2) placing the separated solid in a PFI mill, setting the grinding tooth spacing to 1.25 mm, setting the number of revolutions to 10,000, and beating to obtain a tobacco stem slurry having a beating degree of 70° SR;

[0098] (3) the prepared tobacco stem slurry, the tobacco chip slurry (beating degree of 65°SR), the wood pulp (pulp concentration of 5.0%) and the light calcium carbonate are mixed in a ratio of 5.5:3:1:1.5 (the above ratios are calculated based on the absolute dry weight of the materials, and the total weight is 2 g), and then guar gum (additional 0.4 g) is added and uniformly mixed to prepare a mixed slurry;

[0099] (4) The prepared mixed slurry is sheeted into reconstituted tobacco leaf base sheets using a rapid Kaeser sheeting machine.

[0100] Application Example 1

[0101] This application example provides a reconstituted tobacco leaf, and the preparation method thereof comprises:

[0102] The coating liquid of the reconstituted tobacco leaf substrate of Example 1 was evenly applied to the front and back sides of the substrate at a coating rate of 40% (40% of the absolute dry substrate mass), and the reconstituted tobacco leaf sample was prepared after drying.

[0103] Application Example 2-6

[0104] This application example provides 5 types of reconstituted tobacco leaves, which differ from application example 1 only in that, in the preparation method, the reconstituted tobacco leaf substrates of Examples 2-6 are respectively coated with a coating liquid at a coating rate of 40% (40% of the absolute dry substrate mass) and evenly applied to the front and back sides of the substrates, and the reconstituted tobacco leaf samples are obtained after drying.

[0105] Comparative Application Examples 1-3

[0106] This comparative application example provides three types of reconstituted tobacco leaves, which differ from application example 1 only in that, in the preparation method, the reconstituted tobacco leaf substrates of comparative examples 1-3 are respectively coated with a coating liquid at a coating rate of 40% (40% of the absolute dry substrate mass) and evenly applied to the front and back sides of the substrates, and the reconstituted tobacco leaf samples are obtained after drying.

[0107] Test Example 1

[0108] Surface morphology analysis of different types of tobacco stem raw materials and substrate samples

[0109] SEM testing conditions:

[0110] The electron beam acceleration voltage was 5 kV and the magnification was 500 times.

[0111] The epidermal morphology, cross-section morphology and longitudinal section morphology of long stalks, extra-long stalks, short stalks and stalk heads were analyzed using SEM. The results are shown in Figure 2-4The surface morphology of the substrates of Example 1 and Examples 4-6 was analyzed, and the results are shown in Figure 1 .

[0112] Depend on Figure 2-4 It can be seen that from left to right are the morphological pictures of long stem, extra long stem, short stem and stem head. Figure 2 The middle epidermal surface showed varying degrees of wrinkles and tiny particles. Among them, the epidermal fibers of long stalks and extra-long stalks were arranged relatively tightly, with less granular matter, and the overall fiber bundle structure was relatively regular. In contrast, the epidermal fibers of short stalks and stalk heads were arranged relatively loosely, with obvious cracks and wrinkles, and more granular matter on the surface. Figure 3 and 4 The differences between different types of tobacco stems in cross-section and longitudinal sections were further demonstrated. These differences were more significant. Long stems and extra-long stems had a large number of relatively regular pore structures inside, and the pore distribution was relatively uniform; while short stems and stem heads had a dense fiber bundle structure with fewer and smaller pores inside, and the fiber bundles on the longitudinal section were arranged in a more disorderly and broken manner.

[0113] In order to explore the influence of tobacco stem raw materials on the surface morphology of substrate samples and the influence of these structural characteristics on their pyrolysis performance, the surface morphology of substrates of JP1, JP2, JP3 and JP4 was further analyzed. The specific results are as follows Figure 1 As shown in the figure (JP1, JP2, JP3 and JP4 from left to right). Figure 1 It can be seen that although the surfaces of all samples are relatively rough, the surface wrinkles of JP1 and JP2 are more significant, and contain a large number of pores and crack structures, while the surfaces of JP3 and JP4 samples are relatively flat. The increase in surface wrinkles and cracks means that during the pyrolysis process, the gas can be more easily released through these cracks and wrinkles, thereby accelerating the pyrolysis rate. At the same time, the rich pore structure indicates that the sample has a large specific surface area, which can provide more heating areas and adsorption sites, and enhance the uniformity and sufficiency of pyrolysis and combustion reactions. Combined with the tobacco stem raw material composition of different substrate samples, it can be seen that the substrate containing a higher proportion of super-long stems and long stems has more developed surface wrinkles and pore structures, which is attributed to the rich long fibers in super-long stems and long stems. These fibers are easy to form an interwoven three-dimensional network structure due to their large surface area and high flexibility during the molding process. During the drying process, the bending and folding of the fibers lead to surface wrinkles and richer pore structures. In addition, these pore structures also provide channels and space for the removal of volatile gases generated during pyrolysis and combustion and the transport of oxygen.

[0114] Test Example 2

[0115] Thermogravimetric analysis of different substrate samples

[0116] TG test conditions:

[0117] 10 mg of the samples of Examples 1 and 4-6 were weighed and placed in a crucible for heating. The operating parameters were as follows: the temperature range was 25-800°C, the heating rate was 20°C / min, and the atmosphere was air and N 2 , the gas flow rate is 20mL / min.

[0118] The surface morphology of the above examples was analyzed by TG, and the results are shown in Figure 5 .

[0119] Figure 5 a and b are N of JP1, JP2, JP3 and JP4 respectively. 2 a and d are the TG and DTG graphs of JP1, JP2, JP3 and JP4 under air atmosphere, respectively.

[0120] Depend on Figure 5 It can be seen that the N 2 The weight loss under atmosphere can be divided into the following three stages, among which 40-200℃ is stage I, 200-400℃ is stage II, and 400-800℃ is stage III; under air atmosphere, the weight loss of different samples can be divided into the following four stages, among which 40-200℃ is stage I, 200-400℃ is stage II, 400-550℃ is stage III, and 550-800℃ is stage IV.

[0121] In stage I, the weight loss of all substrates mainly comes from the evaporation of free water. Comparing the weight loss under the two atmospheres, it is found that the weight loss in air is always higher than that in N2O3. 2 atmosphere, which is due to the functional groups in the cellulose molecules and O 2 Thermal oxidation reaction occurs, which promotes the pyrolysis rate of cellulose ( Figure 5 b and d). In addition, the hydroxyl groups in cellulose react with O at high temperatures. 2 reaction, resulting in partial structural degradation or carbon chain breakage.

[0122] In stage II, the weight loss and pyrolysis rate of all substrate samples reached the maximum, mainly because the composition of the samples included cellulose, hemicellulose and lignin, and the pyrolysis temperature was 200-400°C. The weight loss rate in this stage was similar in the two atmospheres, with a difference of no more than 3%, indicating that the pyrolysis reaction was mainly caused by the breaking of chemical bonds of cellulose and hemicellulose. Although different samples differed in surface morphology and fiber morphology, almost all cellulose and hemicellulose were completely decomposed at this stage to produce char or volatile substances.

[0123] In stage III, the weight loss of samples in air atmosphere was significantly higher than that of N 2 atmosphere, which is related to the high temperature O 2The oxidation reaction of coke produces CO and CO 2 Small molecule gases ( Figure 5 ). 2 Under the atmosphere, the weight loss of each substrate sample is: JP1 (20.76%), JP2 (24.50%), JP3 (28.39%) and JP4 (32.43%). Due to its good winding ability and rich pore structure, long cellulose is evenly heated during the high-temperature carbonization process to avoid structural collapse; while short fibers are loose in structure and unevenly heated during the pyrolysis process, which easily leads to the collapse of the carbon structure and the formation of an amorphous structure. When entering the fourth stage, the weight loss of all substrate samples slowly decreases, and when the temperature reaches 750℃, an obvious weight loss peak appears, indicating that the carbonization process has been completed, but as the temperature further increases, the pore structure may shrink or collapse, destroying the original graphitized structure and causing the rearrangement of carbon atoms.

[0124] In summary, the present invention analyzes the pyrolysis behavior of tobacco stem substrate under different atmosphere conditions. 2 In the atmosphere, the weight loss of the samples was mainly affected by the evaporation of free water and the pyrolysis of cellulose, while in the air atmosphere, the oxidation reaction significantly accelerated the pyrolysis process. Among all the samples, JP1 was rich in long cellulose and showed better stability and structural integrity at high temperatures. Therefore, JP1 was identified as the best product, which will improve the pyrolysis efficiency and product quality and has a wide range of application potential.

[0125] Test Example 3

[0126] Sensory evaluation experiment

[0127] Evaluation method: For the same batch of samples, the materials of the cigarettes are consistent and the distribution of tobacco shreds should be uniform. The smokers refer to the samples of Example 1-6 and Comparative Application Example 1-3 in Table 1 for sensory evaluation, and score each indicator in turn. Each indicator is scored in units of 0.5 points. The number of people participating in the evaluation is 5, and the final result is recorded as the average score of all participants. The results are shown in Table 2.

[0128] Table 1

[0129]

[0130]

[0131] Table 2

[0132]

[0133] As can be seen from Table 2, the reconstituted tobacco leaves of Application Examples 1-3 have a full and rich aroma, a mellow smoke flavor, no obvious odor, a weak burning sensation and a dry sensation, and a clean aftertaste. This is because the substrate prepared by the specific method of the present invention has a more complete mesh structure, which promotes uniform and stable combustion, reduces the impurities caused by incomplete combustion, and improves the fullness and purity of the aroma. The aroma of Application Example 4 is relatively thin, with a slightly woody smell and a slightly bitter aftertaste; Application Examples 5-6 have insufficient aroma, lack of layering, and obvious impurities and bitterness; the aroma of Application Examples 1-3 is acceptable, but the concentration is slightly lacking, and the aftertaste is slightly bitter. In summary, adjusting the proportion of tobacco stem raw materials used, and adding tobacco pulp and wood pulp during the preparation process can significantly improve the richness and mellowness of the aroma of reconstituted tobacco leaves, and reduce the residual impurities and aftertaste.

[0134] The applicant declares that the present invention uses the above-mentioned embodiments to illustrate the preparation method of a reconstituted tobacco leaf substrate of the present invention, its product and application, 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.

[0135] 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.

[0136] 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 a reconstituted tobacco leaf substrate, characterized in that: The preparation method comprises: (1) soaking tobacco stem raw materials in deionized water, and then dispersing and pulping to obtain tobacco stem slurry; (2) Tobacco stem slurry, tobacco pulp, wood pulp, calcium carbonate and an adhesive are mixed to obtain a mixed slurry, which is then sheeted to obtain a base sheet.

2. The method for preparing reconstituted tobacco according to claim 1, characterized in that: The mass ratio of the tobacco stem raw material to deionized water in step (1) is 1:(5-15); Preferably, the tobacco stem raw material includes any one of extra-long stems, long stems, short stems or stem heads, or a combination of at least two of them; the length of the extra-long stems is greater than or equal to 40 mm; the length of the long stems is greater than or equal to 20 mm and less than 40 mm; the length of the short stems is less than 20 mm; Preferably, the tobacco stem raw material is a combination of extra-long stems, long stems, short stems and stem heads.

3. The method for preparing the reconstituted tobacco leaf substrate according to claim 1 or 2, characterized in that: The soaking temperature in step (1) is 60-70° C. and the soaking time is 20-40 min; Preferably, solid-liquid separation is performed after the soaking.

4. The method for preparing the reconstituted tobacco leaf substrate according to claim 3, characterized in that: The specific steps of the decongestion in step (1) are: The tobacco stem raw material soaked in deionized water is placed in a deflaking machine, deionized water is added, and the mixture is stirred to obtain a deflaked slurry; Preferably, the amount of deionized water added is 1-5 times the weight of the tobacco stem raw material; Preferably, the stirring time is 8-20 min.

5. The method for preparing the reconstituted tobacco leaf substrate according to any one of claims 1 to 4, characterized in that: The specific steps of pulping in step (1) are: The deflaked pulp is introduced into a PFI mill and pulped to obtain tobacco stem pulp; Preferably, the grinding tooth spacing of the PFI mill is 1-1.5 mm; Preferably, the number of revolutions of the beating process is 8000-15000 revolutions; Preferably, the tobacco stem slurry has a beating degree of 65-70° SR.

6. The method for preparing the reconstituted tobacco leaf substrate according to any one of claims 1 to 5, characterized in that: The absolute dry mass ratio of the tobacco stem slurry, tobacco pulp, wood pulp and calcium carbonate in step (2) is (3-7):(2-5):(0.1-1):(1-2); Preferably, the amount of the adhesive added is 15-25% of the total amount of the tobacco stem pulp, tobacco pulp, wood pulp and calcium carbonate; Preferably, the adhesive comprises any one of guar gum, sodium carboxymethyl cellulose, xanthan gum or gelatin, or a combination of at least two of them.

7. The method for preparing the reconstituted tobacco leaf substrate according to any one of claims 1 to 6, characterized in that: The raw materials for preparing the tobacco pulp include any one of tobacco leaves, tobacco shreds or tobacco foam, or a combination of at least two of them; Preferably, the beating degree of the tobacco pulp is 60-65°SR; Preferably, the concentration of the wood pulp is 3-8%.

8. The method for preparing the reconstituted tobacco leaf substrate according to any one of claims 1 to 7, characterized in that: The gram weight of the reconstituted tobacco leaf base sheet is 55-60 g / m 2 , the water content is 10-15%.

9. A reconstituted tobacco leaf substrate, characterized in that: The reconstituted tobacco leaf substrate is prepared by the method according to any one of claims 1 to 8.

10. Use of the reconstituted tobacco base sheet according to claim 9 in preparing reconstituted tobacco.

Images