Loose, pliable, and set-resistant paper process reconstituted tobacco and method of making

Abstract

The present application relates to a kind of loose, flexible and anti-caking papermaking method reconstituted tobacco and its preparation method, the preparation raw material of the papermaking method reconstituted tobacco includes: tobacco fiber slurry, broad-leaved wood fiber slurry, calcium carbonate filler, tobacco concentrated extraction, molecular bond targeted ablation agent, anti-caking loose modifier, biological crosslinking flexible agent and food-grade binder.For the technical defects of existing reconstituted tobacco fiber crosslinking, easy to be caked, poor flexibility, insufficient air permeability, loose and strength conflict, the present application breaks the hydrogen bond between fibers, hydroxyl crosslinking bond, pectin adhesion bond by molecular bond targeted ablation agent, but does not damage the fiber main chain;Through anti-caking loose modifier, three-dimensional loose skeleton is constructed, and fiber adhesion is blocked;Through biological crosslinking flexible agent, loose and strength are balanced;Each component cooperates, synergistically, so that the prepared reconstituted tobacco is long-acting anti-caking, high-loose, high-flexible, high mechanical strength, and suitable for industrialized stable production.

Description

Technical Field

[0001] This invention belongs to the field of reconstituted tobacco preparation technology, and relates to a loose, flexible and anti-caking papermaking reconstituted tobacco and its preparation method. Background Technology

[0002] Reconstituted tobacco using the papermaking process can efficiently recover tobacco waste such as tobacco stems and dust, and is an important auxiliary material in cigarette formulation, playing a role in reducing tar and harmful substances, stabilizing combustion, and regulating smoke quality. In industrial production, reconstituted tobacco generally suffers from problems such as tight fiber cross-linking, dense structure, easy caking during long-term storage, poor flexibility, insufficient air permeability, and high processing losses.

[0003] During the pulping, rolling, and high-temperature drying processes of traditional reconstituted tobacco, a large number of hydrogen bonds, hydroxyl cross-linking bonds, and pectin adhesive bonds are formed between the fibers, resulting in tightly packed fibers. During storage, the molecular forces continue to increase, leading to hardening of the sheets, pore blockage, easy breakage when shredded, easy extinguishing when smoked, and heavy impurities in the smoke.

[0004] Existing improvement methods mostly involve simple physical fluffing or the addition of simple additives, which only address the symptoms and not the root cause. It is difficult to balance looseness and strength, resulting in easily rebounding plates. There is a lack of systematic modification solutions, which restricts the upgrading of high-end cigarette quality. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the purpose of this invention is to provide a loose, flexible and anti-caking reconstituted tobacco leaf made by papermaking and its preparation method.

[0006] To achieve this objective, the present invention employs the following technical solution:

[0007] In a first aspect, the present invention provides a loose, flexible, and anti-caking reconstituted tobacco leaf produced by papermaking, wherein the raw materials for preparing the reconstituted tobacco leaf by papermaking include: tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler, concentrated tobacco extract, molecular bond targeting dissolving agent, anti-caking loose modifier, bio-crosslinking flexible agent, and food-grade binder.

[0008] To address the technical shortcomings of existing reconstituted tobacco fibers, such as severe cross-linking, easy caking, poor flexibility, insufficient air permeability, and the contradiction between looseness and strength, this invention uses a molecular bond-targeting ablative agent to break hydrogen bonds, hydroxyl cross-linking bonds, and pectin adhesion bonds between fibers without damaging the fiber backbone; it constructs a three-dimensional loose skeleton through an anti-caking looseness modifier to prevent fiber adhesion; and it balances looseness and strength through a bio-cross-linking flexibility agent. The components work together synergistically to produce reconstituted tobacco with long-lasting anti-caking properties, high looseness, high flexibility, and high mechanical strength, making it suitable for stable industrial production.

[0009] Preferably, the raw materials for preparing the papermaking reconstituted tobacco leaf, by oven-dry weight, include: 40-50 parts tobacco fiber pulp, 5-8 parts hardwood fiber pulp, 2-5 parts calcium carbonate filler, 35-40 parts tobacco concentrated extract, 0.20-0.40 parts molecular bond targeting dissolving agent, 0.20-0.35 parts anti-caking loosening modifier, 0.25-0.45 parts bio-crosslinking flexibility agent, and 0.35-0.55 parts food-grade binder.

[0010] The oven-dry weight fraction of the tobacco fiber pulp can be selected from 40 parts, 42 parts, 44 parts, 46 parts, 48 ​​parts, 50 parts, etc.; the oven-dry weight fraction of the hardwood fiber pulp can be selected from 5.0 parts, 5.5 parts, 6.0 parts, 6.5 parts, 7.0 parts, 7.5 parts, 8.0 parts, etc.; the oven-dry weight fraction of the calcium carbonate filler can be selected from 2.0 parts, 2.5 parts, 3.0 parts, 3.5 parts, 4.0 parts, 4.5 parts, 5.0 parts, etc.; the oven-dry weight fraction of the tobacco concentrated extract can be selected from 35 parts, 36 parts, 37 parts, 38 parts, 39 parts, 40 parts, etc.; the oven-dry weight fraction of the molecular bond targeting ablative agent... The quantities can be selected from 0.20 parts, 0.25 parts, 0.30 parts, 0.35 parts, 0.40 parts, etc.; the oven-dry weight of the anti-caking and loosening modifier can be selected from 0.20 parts, 0.25 parts, 0.30 parts, 0.35 parts, etc.; the oven-dry weight of the bio-crosslinking flexible agent can be selected from 0.25 parts, 0.30 parts, 0.35 parts, 0.40 parts, 0.45 parts, etc.; the oven-dry weight of the food-grade binder can be selected from 0.35 parts, 0.40 parts, 0.45 parts, 0.50 parts, 0.55 parts, etc.; other specific values ​​not listed within the above ranges can be selected, and will not be elaborated here.

[0011] Preferably, the molecular bond-targeting ablative agent is selected from any one or a combination of at least two of hydroxyethyl cellulose, sodium hexametaphosphate, or neutral cellulase.

[0012] Preferably, the molecular bond-targeting ablative agent is a combination of hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase.

[0013] This invention also creatively discovers that when hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase are used simultaneously for crosslinking and ablation pretreatment of tobacco fiber pulp, the three have a synergistic effect, resulting in reconstituted tobacco leaves with better anti-caking properties, flexibility, looseness, and mechanical strength.

[0014] Preferably, the mass ratio of hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase is (2-3):(1-2):1, wherein the specific values ​​in (2-3) can be 2, 2.2, 2.4, 2.5, 2.7, 2.8, 3, etc.; the specific values ​​in (1-2) can be 1, 1.2, 1.4, 1.5, 1.7, 1.8, 2, etc.; other specific values ​​not listed above within the above ranges can be selected, and will not be elaborated here.

[0015] Preferably, the anti-caking and loosening modifier is selected from any one or a combination of at least two of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, or phytosterols.

[0016] Preferably, the anti-caking and loosening modifier is a combination of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, and phytosterols.

[0017] This invention also creatively discovers that when carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, and phytosterols are used as adjuvants and mixed with tobacco fiber pulp, the four components work synergistically to produce reconstituted tobacco leaves with superior anti-caking properties, flexibility, looseness, and mechanical strength.

[0018] Preferably, the mass ratio of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, and phytosterol is (2-3):(1-2):(1-2):1, wherein the specific values ​​in (2-3) can be 2, 2.2, 2.4, 2.5, 2.7, 2.8, 3, etc.; the specific values ​​in (1-2) can be 1, 1.2, 1.4, 1.5, 1.7, 1.8, 2, etc.; other specific values ​​not listed above within the above ranges can be selected, and will not be elaborated here.

[0019] Preferably, the bio-crosslinking flexibility agent is selected from any one or a combination of at least two of modified starch, sodium alginate, or gluten.

[0020] Preferably, the bio-crosslinking flexibility agent is a combination of modified starch, sodium alginate, and gluten.

[0021] This invention also creatively discovers that when modified starch, sodium alginate, and gluten are used simultaneously as adjuvants and mixed with tobacco fiber pulp, the three have a synergistic effect, resulting in reconstituted tobacco leaves with better anti-caking properties, flexibility, looseness, and mechanical strength.

[0022] Preferably, the mass ratio of modified starch, sodium alginate and gluten is (1-3):(1-3):(1-3), wherein the specific values ​​in (1-3) can be 1, 1.2, 1.4, 1.5, 1.7, 1.8, 2, 2.2, 2.4, 2.5, 2.7, 2.8, 3, etc.; other specific values ​​not listed within this range can be selected, and will not be elaborated here.

[0023] Preferably, the food-grade binder is selected from any one or a combination of at least two of starch, guar gum, or carboxymethyl cellulose.

[0024] Preferably, the tobacco fiber pulp and tobacco concentrate extract are prepared by a method comprising the following steps:

[0025] Tobacco stems and tobacco dust are used as raw materials, and they are mixed with water for hot extraction. After extraction, they are separated by centrifugation to obtain tobacco extract and tobacco fiber residue. The tobacco extract is concentrated under reduced pressure to obtain concentrated tobacco extract. The tobacco fiber residue is pulped to obtain tobacco fiber pulp.

[0026] Preferably, the mass ratio of the raw material to water is 1:(5-10), such as 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, etc. Other specific values ​​not listed within this range can be selected, and will not be elaborated here.

[0027] Preferably, the hot extraction is carried out at 55-65℃ (e.g., 55℃, 57℃, 58℃, 60℃, 62℃, 64℃, 65℃, etc.) for 30-50 min (e.g., 30 min, 35 min, 40 min, 45 min, 50 min, etc.); other specific point values ​​not listed above within the above range can be selected, and will not be elaborated here.

[0028] Preferably, the density of the concentrated tobacco extract is 1.18-1.20 g / cm³. 3 For example, 1.18 g / cm³ 3 1.19 g / cm 3 1.20 g / cm 3 Other unlisted point values ​​within this range can also be selected, and will not be elaborated on here.

[0029] Preferably, the beating degree of the tobacco fiber pulp is 18-28°SR, such as 18°SR, 19°SR, 20°SR, 22°SR, 24°SR, 25°SR, 27°SR, 28°SR, etc. Other specific values ​​not listed in this range can be selected, and will not be elaborated here.

[0030] Preferably, the hardwood fiber pulp is prepared by a method comprising the following steps:

[0031] After soaking the hardwood pulp board in hot water, centrifuge it and then pulp it to obtain hardwood fiber pulp.

[0032] Preferably, the mass ratio of the hardwood pulp board to water is 1:(5-10), such as 1:5, 1:6, 1:7, 1:8, 1:9, 1:10, etc. Other specific values ​​not listed within this range can be selected, and will not be elaborated here.

[0033] Preferably, the hot water temperature is 55-65℃ (e.g., 55℃, 57℃, 58℃, 60℃, 61℃, 62℃, 63℃, 64℃, 65℃, etc.).

[0034] Preferably, the soaking is performed for 30-50 minutes (e.g., 30 minutes, 35 minutes, 45 minutes, 50 minutes, etc.).

[0035] Preferably, the beating degree of the hardwood fiber pulp is 18-28°SR, such as 18°SR, 19°SR, 20°SR, 22°SR, 24°SR, 25°SR, 27°SR, 28°SR, etc.

[0036] All other point values ​​not listed above within the above range can be selected, and will not be elaborated on here.

[0037] In a second aspect, the present invention provides a method for preparing reconstituted tobacco leaves according to the papermaking method described in the first aspect, the method comprising the following steps:

[0038] (1) Tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler and molecular bond targeting ablative are mixed and stirred to obtain modified pulp;

[0039] (2) Mix the modified slurry with the food-grade binder;

[0040] (3) Then mix and stir with anti-caking loose modifier and bio-crosslinking flexible agent, and vacuum defoam to obtain mixed slurry;

[0041] (4) The mixed slurry is formed into shape, and tobacco concentrated extract is coated on the surface of the wet substrate sheet after forming;

[0042] (5) After coating, the tobacco leaves are dried to obtain reconstituted tobacco leaves.

[0043] Preferably, the mixing and stirring in step (1) is carried out at 40-50℃ (e.g., 40℃, 42℃, 45℃, 48℃, 50℃, etc.) for 30-45 min (e.g., 30 min, 33 min, 35 min, 40 min, 45 min, etc.).

[0044] Preferably, the mixing and stirring in step (2) is carried out at 20-35℃ (e.g., 20℃, 25℃, 30℃, 32℃, 35℃, etc.) for 10-20 min (e.g., 10 min, 13 min, 15 min, 18 min, 20 min, etc.).

[0045] Preferably, the mixing and stirring in step (3) is carried out at 40-45℃ (e.g., 40℃, 42℃, 43℃, 44℃, 45℃, etc.) for 30-40 min (e.g., 30 min, 33 min, 35 min, 38 min, 40 min, etc.).

[0046] Preferably, the quantitative control in the roll forming process of step (4) is 55-58 g / m³. 2 For example, 55 g / m 2 56 g / m 2 57 g / m 2 58 g / m 2 wait.

[0047] Preferably, the coating control coating rate in step (4) is 39-40%.

[0048] Preferably, the drying in step (5) employs a three-stage gradient drying process:

[0049] First stage: Dry at 80-90℃ (e.g., 80℃, 84℃, 87℃, 90℃, etc.) until the moisture content is 17-20% (e.g., 17%, 18%, 19%, 20%, etc.).

[0050] The second stage: Dry at 95-105℃ (e.g., 95℃, 98℃, 102℃, 105℃, etc.) until the moisture content is 13-15% (e.g., 13%, 14%, 15%, etc.).

[0051] The third stage: Dry at 80-95℃ (e.g., 80℃, 85℃, 90℃, 95℃, etc.) until the moisture content is 11-12% (e.g., 11%, 11.5%, 12%, etc.).

[0052] All other point values ​​not listed above within the above range can be selected, and will not be elaborated on here.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] To address the technical shortcomings of existing reconstituted tobacco fibers, such as severe cross-linking, easy caking, poor flexibility, insufficient air permeability, high processing losses, and a contradiction between looseness and strength, this invention uses a molecular bond-targeting ablative agent to break hydrogen bonds, hydroxyl cross-linking bonds, and pectin adhesion bonds between fibers without damaging the fiber backbone; it constructs a three-dimensional loose skeleton through an anti-caking loosening modifier to prevent fiber adhesion; and it balances looseness and strength through a bio-cross-linking flexibility agent. The components work together synergistically to produce reconstituted tobacco with long-lasting anti-caking properties, high looseness, high flexibility, and high mechanical strength, making it suitable for stable industrial production. Attached Figure Description

[0055] Figure 1 This is an electron micrograph of the reconstituted tobacco leaf obtained in Example 1;

[0056] Figure 2 This is an electron micrograph of the reconstituted tobacco leaf prepared in Comparative Example 4. Detailed Implementation

[0057] The technical solution of the present invention will be further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments described are merely illustrative of the present invention and should not be construed as limiting the invention.

[0058] The sources of some of the raw materials used in the following examples or comparative examples are as follows:

[0059]

[0060]

[0061] All other raw materials are commercially available in this field.

[0062] Example 1

[0063] This embodiment provides a reconstituted tobacco leaf, the raw materials of which, by oven-dry weight, are: 46 parts tobacco fiber pulp, 6.5 parts hardwood fiber pulp, 3.5 parts calcium carbonate filler, 40 parts tobacco concentrated extract, 0.30 parts molecular bond targeting dissolving agent, 0.25 parts anti-caking and loosening modifier, 0.35 parts bio-crosslinking flexibility agent, and 0.40 parts food-grade binder.

[0064] The molecular bond-targeting ablative agent is a combination of hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase in a mass ratio of 2:1.5:1; the anti-caking and loosening modifier is a combination of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, and phytosterols in a mass ratio of 2:1.5:1:1; the bio-crosslinking flexibility agent is a combination of modified starch, sodium alginate, and gluten in a mass ratio of 2:2:1; and the food-grade binder is guar gum.

[0065] Its preparation method is as follows:

[0066] (1) Mix tobacco stems and tobacco dust at a mass ratio of 3:7; add deionized water at a material-to-liquid mass ratio of 1:8, and extract at 60℃ for 40 min; after extraction, centrifuge to obtain tobacco extract and tobacco fiber residue; concentrate the tobacco extract under reduced pressure to obtain a density of 1.20 g / cm³. 3 The tobacco concentrate; the tobacco fiber residue is milled in multiple stages to prepare a tobacco fiber pulp with a beating degree of 25°SR, for later use.

[0067] (2) Add the hardwood pulp board to hot water at a ratio of 1:8, soak at 60°C for 40 min, centrifuge, and then pulp it with a pulper to prepare hardwood fiber pulp with a freeness of 25°SR for later use.

[0068] (3) Mix tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler and molecular bond targeting ablative agent and stir at 45°C for 40 min to obtain modified pulp;

[0069] (4) Mix the modified slurry with the food-grade binder and stir at 25°C for 15 min;

[0070] (5) Then mix with anti-caking loose modifier and bio-crosslinking flexible agent, stir at 40°C for 35 min, and defoam under vacuum to obtain mixed slurry;

[0071] (6) Form the mixed slurry into shape, controlling the quantitative amount to 56 g / m³. 2 After molding, a concentrated tobacco extract is coated onto the surface of the wet substrate sheet, with a coating rate of 40%.

[0072] (7) After coating, three-stage gradient drying is adopted: the first stage: low temperature pre-drying at 87℃, the moisture content is reduced to 18%; the second stage: slow drying at 98℃ to loosen the soil, the moisture content is reduced to 14%; the third stage: humidity conditioning and shaping at 90℃; the whole process is disturbed by a gentle breeze to control the moisture content of the finished product to 11.5%; the finished reconstituted tobacco leaves are obtained by slitting.

[0073] The reconstituted tobacco leaves were observed under an electron microscope. The procedure was as follows: samples were cut into 10 mm × 5 mm specimens and equilibrated at 22℃ and 60%RH for 24 h; vacuum dried at 40℃ for 4 h to remove moisture; a flat cross-section was obtained by liquid nitrogen cryogenic fracturing, and conductive carbon adhesive was fixed onto a copper stage; a conductive gold film was formed by ion sputtering for 100 s. The electron microscope was operated at an accelerating voltage of 2.0 kV, in secondary electron mode, and microscopic images of the sample surface and cross-section were acquired at 500x magnification. Figure 1 As shown in the figure, the sample has a loose, porous, continuous network formed by interwoven fibers. The filler is evenly dispersed without agglomerated hard areas, and the internal interconnected pores are abundant. The fibers are flexibly bonded and overlapped. The microporous structure is stable and can buffer the external forces of drying and processing. The substrate is soft and not easy to clump.

[0074] Example 2

[0075] This embodiment provides a reconstituted tobacco leaf, the raw materials of which, by oven-dry weight, are: 44 parts tobacco fiber pulp, 7.0 parts hardwood fiber pulp, 4.0 parts calcium carbonate filler, 39 parts tobacco concentrated extract, 0.25 parts molecular bond targeting dissolving agent, 0.30 parts anti-caking loosening modifier, 0.30 parts bio-crosslinking flexibility agent, and 0.45 parts food-grade binder.

[0076] The molecular bond-targeting ablative agent is a combination of hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase in a mass ratio of 3:2:1; the anti-caking and loosening modifier is a combination of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, and phytosterols in a mass ratio of 3:1:1:1; the bio-crosslinking flexibility agent is a combination of modified starch, sodium alginate, and gluten in a mass ratio of 1.5:1.5:1; and the food-grade binder is starch.

[0077] Its preparation method is as follows:

[0078] (1) Mix tobacco stems and tobacco dust at a mass ratio of 3:7; add deionized water at a material-to-liquid mass ratio of 1:6, and extract at 55℃ for 50 min; after extraction, centrifuge to obtain tobacco extract and tobacco fiber residue; concentrate the tobacco extract under reduced pressure to obtain a density of 1.18 g / cm³. 3 The tobacco concentrate; the tobacco fiber residue is milled in multiple stages to prepare a tobacco fiber pulp with a beating degree of 24°SR, for later use.

[0079] (2) Add the hardwood pulp board to hot water at a ratio of 1:6, soak at 55°C for 50 min, centrifuge, and then pulp it with a pulper to prepare hardwood fiber pulp with a freeness of 24°SR for later use.

[0080] (3) Mix tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler and molecular bond targeting ablative agent and stir at 40°C for 45 min to obtain modified pulp;

[0081] (4) Mix the modified slurry with the food-grade binder and stir at 30°C for 10 min;

[0082] (5) Then mix with anti-caking loose modifier and bio-crosslinking flexible agent, stir at 45°C for 30 min, and defoam under vacuum to obtain mixed slurry;

[0083] (6) Form the mixed slurry into shape, controlling the quantitative amount to 55 g / m³. 2 After molding, a concentrated tobacco extract is coated onto the surface of the wet substrate sheet, with a coating rate of 39%.

[0084] (7) After coating, three-stage gradient drying is adopted: the first stage: low temperature pre-drying at 84℃, the moisture content is reduced to 19%; the second stage: slow drying at 102℃ to loosen the leaves, the moisture content is reduced to 13%; the third stage: humidity conditioning and shaping at 85℃; the whole process is disturbed by a gentle breeze to control the moisture content of the finished product to 12%; the finished reconstituted tobacco leaves are obtained by slitting.

[0085] Example 3

[0086] This embodiment provides a reconstituted tobacco leaf, the raw materials of which, by oven-dry weight, are: 48 parts tobacco fiber pulp, 6.0 parts hardwood fiber pulp, 3.0 parts calcium carbonate filler, 39 parts concentrated tobacco extract, 0.35 parts molecular bond targeting dissolving agent, 0.35 parts anti-caking and loosening modifier, 0.25 parts bio-crosslinking flexibility agent, and 0.35 parts food-grade binder.

[0087] The molecular bond-targeting ablative agent is a combination of hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase in a mass ratio of 2:2:1; the anti-caking and loosening modifier is a combination of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, and phytosterols in a mass ratio of 2:1:2:1; the bio-crosslinking flexibility agent is a combination of modified starch, sodium alginate, and gluten in a mass ratio of 1:1:1; and the food-grade binder is carboxymethyl cellulose.

[0088] Its preparation method is as follows:

[0089] (1) Mix tobacco stems and tobacco dust at a mass ratio of 3:7; add deionized water at a material-to-liquid mass ratio of 1:10, and extract at 65℃ for 30 min; after extraction, centrifuge to obtain tobacco extract and tobacco fiber residue; concentrate the tobacco extract under reduced pressure to obtain a density of 1.18 g / cm³. 3 The tobacco concentrate; the tobacco fiber residue is milled in multiple stages to prepare a tobacco fiber pulp with a beating degree of 28°SR, for later use.

[0090] (2) Add the hardwood pulp board to hot water at a ratio of 1:10, soak at 65°C for 30 min, centrifuge, and then pulp it with a pulper to prepare hardwood fiber pulp with a freeness of 28°SR for later use.

[0091] (3) Mix tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler and molecular bond targeting ablative agent and stir at 50°C for 30 min to obtain modified pulp;

[0092] (4) Mix the modified slurry with the food-grade binder and stir at 25°C for 10 min;

[0093] (5) Then mix with anti-caking loose modifier and bio-crosslinking flexible agent, stir at 45°C for 40 min, and defoam under vacuum to obtain mixed slurry;

[0094] (6) Form the mixed slurry into shape, controlling the quantitative amount to 58 g / m³. 2 After molding, a concentrated tobacco extract is coated onto the surface of the wet substrate sheet, with a coating rate of 39%.

[0095] (7) After coating, three-stage gradient drying is adopted: the first stage: low temperature pre-drying at 90℃, the moisture content is reduced to 17%; the second stage: slow drying at 95℃ to loosen the soil, the moisture content is reduced to 15%; the third stage: humidity conditioning and shaping at 95℃; the whole process is disturbed by a gentle breeze to control the moisture content of the finished product to 12%; the finished reconstituted tobacco leaves are obtained by slitting.

[0096] Example 4

[0097] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 being: the molecular bond-targeting ablative agent lacks hydroxyethyl cellulose, and the reduced amount is allocated proportionally to the mass of sodium hexametaphosphate and neutral cellulase, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0098] Example 5

[0099] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 being: the molecular bond-targeting ablative agent lacks sodium hexametaphosphate, and the reduced amount is allocated proportionally to the mass of hydroxyethyl cellulose and neutral cellulase, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0100] Example 6

[0101] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 being: the molecular bond-targeting ablative agent lacks neutral cellulase, and the reduced amount is allocated proportionally to the mass of hydroxyethyl cellulose and sodium hexametaphosphate, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0102] Example 7

[0103] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 is that the anti-caking and loosening modifier lacks carboxymethyl chitosan and hydroxypropyl methylcellulose, and the reduced amounts are proportionally allocated to the mass of nanoporous diatomaceous earth and phytosterols, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0104] Example 8

[0105] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 is that the anti-caking and loosening modifier lacks nanoporous diatomaceous earth, and the reduced amount is allocated to the mass of carboxymethyl chitosan, hydroxypropyl methylcellulose, and phytosterols, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0106] Example 9

[0107] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 is that the anti-caking and loosening modifier lacks phytosterols, and the reduced amount is proportionally allocated to the mass of carboxymethyl chitosan, hydroxypropyl methylcellulose, and nanoporous diatomaceous earth, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0108] Example 10

[0109] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 being: the bio-crosslinking flexibility agent lacks modified starch, and the reduced amount is allocated proportionally to the mass of sodium alginate and gluten protein, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0110] Example 11

[0111] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 being: the bio-crosslinking flexibility agent lacks sodium alginate, and the reduced amount is allocated proportionally to the mass of modified starch and gluten protein, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0112] Example 12

[0113] This embodiment provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 being: the bio-crosslinking flexibility agent lacks gluten protein, and the reduced amount is allocated proportionally to the mass of modified starch and sodium alginate, while other aspects remain unchanged. The preparation method is the same as in Example 1.

[0114] Comparative Example 1

[0115] This comparative example provides a reconstituted tobacco leaf, the only difference between its preparation materials and those of Example 1 being the absence of a molecular bond-targeting ablative agent; all other aspects remain unchanged. The preparation method is as follows:

[0116] (1) Mix tobacco stems and tobacco dust at a mass ratio of 3:7; add deionized water at a material-to-liquid mass ratio of 1:8, and extract at 60℃ for 40 min; after extraction, centrifuge to obtain tobacco extract and tobacco fiber residue; concentrate the tobacco extract under reduced pressure to obtain a density of 1.20 g / cm³. 3 The tobacco concentrate; the tobacco fiber residue is milled in multiple stages to prepare a tobacco fiber pulp with a beating degree of 25°SR, for later use.

[0117] (2) Add the hardwood pulp board to hot water at a ratio of 1:8, soak at 60°C for 40 min, centrifuge, and then pulp it with a pulper to prepare hardwood fiber pulp with a freeness of 25°SR for later use.

[0118] (3) Mix tobacco fiber pulp, hardwood fiber pulp and calcium carbonate filler at 45°C and stir for 40 min;

[0119] (4) Mix the modified slurry with the food-grade binder and stir at 25°C for 15 min;

[0120] (5) Then mix with anti-caking loose modifier and bio-crosslinking flexible agent, stir at 40°C for 35 min, and defoam under vacuum to obtain mixed slurry;

[0121] (6) Form the mixed slurry into shape, controlling the quantitative amount to 56 g / m³. 2 After molding, a concentrated tobacco extract is coated onto the surface of the wet substrate sheet, with a coating rate of 40%.

[0122] (7) After coating, three-stage gradient drying is adopted: the first stage: low temperature pre-drying at 87℃, the moisture content is reduced to 18%; the second stage: slow drying at 98℃ to loosen the soil, the moisture content is reduced to 14%; the third stage: humidity conditioning and shaping at 90℃; the whole process is disturbed by a gentle breeze to control the moisture content of the finished product to 11.5%; the finished reconstituted tobacco leaves are obtained by slitting.

[0123] Comparative Example 2

[0124] This comparative example provides a reconstituted tobacco leaf, the only difference between its raw materials and those of Example 1 being the absence of an anti-caking and loosening modifier; all other aspects remain unchanged. The preparation method is as follows:

[0125] (1) Mix tobacco stems and tobacco dust at a mass ratio of 3:7; add deionized water at a material-to-liquid mass ratio of 1:8, and extract at 60℃ for 40 min; after extraction, centrifuge to obtain tobacco extract and tobacco fiber residue; concentrate the tobacco extract under reduced pressure to obtain a density of 1.20 g / cm³. 3 The tobacco concentrate; the tobacco fiber residue is milled in multiple stages to prepare a tobacco fiber pulp with a beating degree of 25°SR, for later use.

[0126] (2) Add the hardwood pulp board to hot water at a ratio of 1:8, soak at 60°C for 40 min, centrifuge, and then pulp it with a pulper to prepare hardwood fiber pulp with a freeness of 25°SR for later use.

[0127] (3) Mix tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler and molecular bond targeting ablative agent and stir at 45°C for 40 min to obtain modified pulp;

[0128] (4) Mix the modified slurry with the food-grade binder and stir at 25°C for 15 min;

[0129] (5) Mix with the bio-crosslinking flexibility agent and stir at 40°C for 35 min, then defoam under vacuum to obtain the mixed slurry;

[0130] (6) Form the mixed slurry into shape, controlling the quantitative amount to 56 g / m³. 2 After molding, a concentrated tobacco extract is coated onto the surface of the wet substrate sheet, with a coating rate of 40%.

[0131] (7) After coating, three-stage gradient drying is adopted: the first stage: low temperature pre-drying at 87℃, the moisture content is reduced to 18%; the second stage: slow drying at 98℃ to loosen the soil, the moisture content is reduced to 14%; the third stage: humidity conditioning and shaping at 90℃; the whole process is disturbed by a gentle breeze to control the moisture content of the finished product to 11.5%; the finished reconstituted tobacco leaves are obtained by slitting.

[0132] Comparative Example 3

[0133] This comparative example provides a reconstituted tobacco leaf, the only difference between its preparation materials and those of Example 1 being the absence of a bio-crosslinking flexibility agent; all other aspects remain unchanged. The preparation method is as follows:

[0134] (1) Mix tobacco stems and tobacco dust at a mass ratio of 3:7; add deionized water at a material-to-liquid mass ratio of 1:8, and extract at 60℃ for 40 min; after extraction, centrifuge to obtain tobacco extract and tobacco fiber residue; concentrate the tobacco extract under reduced pressure to obtain a density of 1.20 g / cm³. 3 The tobacco concentrate; the tobacco fiber residue is milled in multiple stages to prepare a tobacco fiber pulp with a beating degree of 25°SR, for later use.

[0135] (2) Add the hardwood pulp board to hot water at a ratio of 1:8, soak at 60°C for 40 min, centrifuge, and then pulp it with a pulper to prepare hardwood fiber pulp with a freeness of 25°SR for later use.

[0136] (3) Mix tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler and molecular bond targeting ablative agent and stir at 45°C for 40 min to obtain modified pulp;

[0137] (4) Mix the modified slurry with the food-grade binder and stir at 25°C for 15 min;

[0138] (5) Mix with the anti-caking and loosening modifier and stir at 40°C for 35 min. Defoam under vacuum to obtain the mixed slurry.

[0139] (6) Form the mixed slurry into shape, controlling the quantitative amount to 56 g / m³. 2 After molding, a concentrated tobacco extract is coated onto the surface of the wet substrate sheet, with a coating rate of 40%.

[0140] (7) After coating, three-stage gradient drying is adopted: the first stage: low temperature pre-drying at 87℃, the moisture content is reduced to 18%; the second stage: slow drying at 98℃ to loosen the soil, the moisture content is reduced to 14%; the third stage: humidity conditioning and shaping at 90℃; the whole process is disturbed by a gentle breeze to control the moisture content of the finished product to 11.5%; the finished reconstituted tobacco leaves are obtained by slitting.

[0141] Comparative Example 4

[0142] This comparative example provides a reconstituted tobacco leaf, the raw materials of which, by oven-dry weight, are: 50 parts tobacco fiber pulp, 12 parts hardwood fiber pulp, 10 parts calcium carbonate filler, 39 parts concentrated tobacco extract, and 0.4 parts guar gum.

[0143] Its preparation method is as follows:

[0144] (1) Mix tobacco stems and tobacco dust at a mass ratio of 3:7; add deionized water at a material-to-liquid mass ratio of 1:8, and extract at 60℃ for 40 min; after extraction, centrifuge to obtain tobacco extract and tobacco fiber residue; concentrate the tobacco extract under reduced pressure to obtain a density of 1.20 g / cm³. 3 The tobacco concentrate; the tobacco fiber residue is milled in multiple stages to prepare a tobacco fiber pulp with a beating degree of 25°SR, for later use.

[0145] (2) Add the hardwood pulp board to hot water at a ratio of 1:8, soak at 60°C for 40 min, centrifuge, and then pulp it with a pulper to prepare hardwood fiber pulp with a freeness of 25°SR for later use.

[0146] (3) Mix tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler, and guar gum and stir at 25°C for 25 minutes to obtain a mixed pulp;

[0147] (4) Form the mixed slurry into shape, controlling the quantitative amount to 56 g / m³. 2 After molding, a concentrated tobacco extract is coated onto the surface of the wet substrate sheet, with a coating rate of 40%.

[0148] (5) After coating, three-stage gradient drying is adopted: the first stage: low temperature pre-drying at 87℃, the moisture content is reduced to 18%; the second stage: slow drying at 98℃ to loosen the soil, the moisture content is reduced to 14%; the third stage: humidity conditioning and shaping at 90℃; the whole process is disturbed by a gentle breeze to control the moisture content of the finished product to 11.5%; the finished reconstituted tobacco leaves are obtained by slitting.

[0149] The reconstituted tobacco leaves were observed under an electron microscope. The procedure was as follows: samples were cut into 10 mm × 5 mm specimens and equilibrated at 22℃ and 60%RH for 24 h; vacuum dried at 40℃ for 4 h to remove moisture; a flat cross-section was obtained by liquid nitrogen cryogenic fracturing, and conductive carbon adhesive was fixed onto a copper stage; a conductive gold film was formed by ion sputtering for 100 s. The electron microscope was operated at an accelerating voltage of 2.0 kV, in secondary electron mode, and microscopic images of the sample surface and cross-section were acquired at 500x magnification. Figure 2 As shown in the figure, the sample has a large number of fibers clustered together, the filler is locally agglomerated, the binder blocks the fiber gaps, the interior is dense with very few interconnected pores, the pores are easy to collapse after drying, the substrate is firm and stiff, with poor looseness and flexibility, and is very easy to clump together.

[0150] Test case

[0151] (1) Evaluation of reconstituted tobacco leaf compaction rate:

[0152] The caking rate of the reconstituted tobacco leaves prepared in Examples 1-12 and Comparative Examples 1-4 after 30 days of storage was evaluated. The evaluation method was as follows: the samples were cut into 100 mm × 100 mm standard test pieces, 20 pieces per group, and equilibrated at 22℃ and 60%RH for 2 h; the test pieces were neatly stacked on a pressure mold, and a static pressure of 0.08 MPa was applied to the cover plate and aged in a constant temperature and humidity chamber at 35℃ and 70%RH for 48 h; after being taken out, the samples were equilibrated at room temperature for 1.5 h, and then placed in a vibrating sieve machine to be shaken at 520 r / min and 12 mm amplitude for 300 s; the number of completely separated single pieces f after shaking was counted, and the caking rate was calculated according to X=(20-f) / (20)×100%. The above operation was repeated 3 times for each group and the average value was taken.

[0153] (2) Evaluation of air permeability of reconstituted tobacco leaves:

[0154] The air permeability (CU) of the reconstituted tobacco leaves obtained in Examples 1-12 and Comparative Examples 1-4 was evaluated. The evaluation method was as follows: a constant pressure difference air permeability tester was used to test the effective area of ​​1 cm². 2 The test pressure difference was 2.0 kPa. The sample was cut into 50 mm × 50 mm specimens and equilibrated at 22℃ and 60%RH for 2 h. After the instrument was preheated and calibrated, the specimens were clamped in a single layer with no air leakage or wrinkles, and 5 specimens were tested in parallel. The maximum and minimum values ​​of one set were removed, and the arithmetic mean of the remaining data was taken as the air permeability of the specimen. The result was retained to one decimal place.

[0155] (3) Evaluation of the thickness of reconstituted tobacco:

[0156] The thickness (cm) of reconstituted tobacco leaves obtained in Examples 1-12 and Comparative Examples 1-4 3The evaluation was conducted using the following method: quantitative determination was performed according to GB / T 451.2-2023, and single-layer thickness was determined according to GB / T 451.3-2002. The sample was equilibrated at 22℃±1℃ and 60%RH±3%RH for 2 hours. Samples were cut into 100 mm × 100 mm specimens, and 10 specimens were tested in parallel. Thickness was measured at 3 points on each specimen, and the average value was taken. The quantitative determination of a single sheet was simultaneously performed, and the single-sheet bulk thickness was calculated using the formula V=h×1000 / W. Extreme values ​​were removed, and the average value was taken, with the result retained to two decimal places.

[0157] (4) Evaluation of the softness of reconstituted tobacco leaves:

[0158] The softness (mN) of the reconstituted tobacco leaves obtained in Examples 1-12 and Comparative Examples 1-4 was evaluated. The evaluation method was as follows: the softness of the reconstituted tobacco leaves was tested according to GB / T 8942—2016. A hand-feel softness tester was used, with a slit width of 5.00 mm, a probe travel speed of 1.20 mm / s, and an indentation depth of 8.0 mm. Samples were cut into 100 mm × 100 mm specimens and equilibrated for 4 h at (23±1)℃ and (50±2)%RH standard atmosphere. Tests were conducted separately in the longitudinal and transverse directions, with 10 specimens tested in parallel in each direction (5 specimens face up and 5 specimens face down). The instrument recorded the peak bending resistance, and the arithmetic mean of the longitudinal and transverse values ​​was calculated, rounded to the nearest integer. The lower the softness value, the better the flexibility of the sample.

[0159] (5) Evaluation of tensile strength of reconstituted tobacco leaves:

[0160] The tensile strength (kN / m) of the reconstituted tobacco leaves obtained in Examples 1-12 and Comparative Examples 1-4 was evaluated according to the YC / T 426 standard for testing the physical properties of reconstituted tobacco leaves. Samples were cut into 150 mm × 15 mm strips and equilibrated under standard temperature and humidity conditions for 24 hours. A paper tensile strength tester was used, with a clamping distance of 100 mm and a tensile speed of 20 mm / min. Ten samples were tested in each group, and the average value was taken. The formula for calculating tensile strength is: Tensile strength (kN / m) = F / b, where F is the maximum tensile force and b is the sample width.

[0161] The test results for the above indicators are shown in Table 1.

[0162] Table 1

[0163]

[0164] As shown in Table 1, compared with the reconstituted tobacco products of Comparative Examples 1-4, the reconstituted tobacco products prepared in this invention break the cross-links between fibers through a molecular bond-targeting ablative agent, construct a three-dimensional loose skeleton and block fiber adhesion through an anti-caking loosening modifier, and balance looseness and strength through a bio-crosslinking flexibility agent. This results in reconstituted tobacco products with superior long-lasting anti-caking properties, looseness and air permeability, flexibility and mechanical strength. Furthermore, the formulations of the molecular bond-targeting ablative agent, the anti-caking loosening modifier, and the bio-crosslinking flexibility agent also affect the anti-caking properties, looseness and air permeability, flexibility and mechanical strength of the reconstituted tobacco products to a certain extent.

[0165] The applicant declares that the technical solution of this invention is illustrated by the above embodiments, but this invention is not limited to the above embodiments, that is, it does not mean that this invention must rely on the above embodiments to be implemented. Those skilled in the art should understand that any improvements to this invention, equivalent substitutions of raw materials for the products of this invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of this invention.

[0166] The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.

[0167] 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 describe the various possible combinations separately.

Claims

1. A papermaking method for reconstituted tobacco leaves that is loose, flexible, and resistant to caking, characterized in that, The raw materials for preparing reconstituted tobacco by the papermaking method include: tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler, concentrated tobacco extract, molecular bond targeting dissolving agent, anti-caking and loosening modifier, bio-crosslinking flexibility agent and food-grade binder.

2. The papermaking method for reconstituted tobacco leaves according to claim 1, characterized in that, The raw materials for preparing reconstituted tobacco by the papermaking method include, by oven-dry weight: 40-50 parts tobacco fiber pulp, 5-8 parts hardwood fiber pulp, 2-5 parts calcium carbonate filler, 35-40 parts tobacco concentrated extract, 0.20-0.40 parts molecular bond targeting dissolving agent, 0.20-0.35 parts anti-caking and loosening modifier, 0.25-0.45 parts bio-crosslinking flexibility agent, and 0.35-0.55 parts food-grade binder.

3. The papermaking method for reconstituted tobacco leaves according to claim 1 or 2, characterized in that, The molecular bond-targeting ablative agent is selected from any one or a combination of at least two of hydroxyethyl cellulose, sodium hexametaphosphate, or neutral cellulase; Preferably, the molecular bond-targeting ablative agent is a combination of hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase; Preferably, the mass ratio of hydroxyethyl cellulose, sodium hexametaphosphate, and neutral cellulase is (2-3):(1-2):

1.

4. The papermaking method for reconstituted tobacco leaves according to any one of claims 1-3, characterized in that, The anti-caking and loosening modifier is selected from any one or a combination of at least two of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, or phytosterols. Preferably, the anti-caking and loosening modifier is a combination of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth, and phytosterols; Preferably, the mass ratio of carboxymethyl chitosan, hydroxypropyl methylcellulose, nanoporous diatomaceous earth and phytosterol is (2-3):(1-2):(1-2):

1.

5. The papermaking method for reconstituted tobacco leaves according to any one of claims 1-4, characterized in that, The bio-crosslinking flexibility agent is selected from any one or a combination of at least two of modified starch, sodium alginate, or gluten. Preferably, the bio-crosslinking flexibility agent is a combination of modified starch, sodium alginate, and gluten; Preferably, the mass ratio of modified starch, sodium alginate and gluten is (1-3):(1-3):(1-3).

6. The papermaking method for reconstituted tobacco leaves according to any one of claims 1-5, characterized in that, The food-grade binder is selected from any one or a combination of at least two of starch, guar gum, or carboxymethyl cellulose. Preferably, the beating degree of the hardwood fiber pulp is 18-28°SR.

7. The papermaking method for reconstituted tobacco leaves according to any one of claims 1-6, characterized in that, The tobacco fiber pulp and tobacco concentrated extract are prepared by a method comprising the following steps: Tobacco stems and tobacco dust are used as raw materials, and they are mixed with water for hot extraction. After extraction, they are centrifuged to obtain tobacco extract and tobacco fiber residue. The tobacco extract is concentrated under reduced pressure to obtain concentrated tobacco extract. The tobacco fiber residue is pulped to obtain tobacco fiber pulp. Preferably, the mass ratio of the raw material to water is 1:(5-10); Preferably, the hot extraction is carried out at 55-65°C for 30-50 minutes; Preferably, the density of the concentrated tobacco extract is 1.18-1.20 g / cm³. 3 ; Preferably, the beating degree of the tobacco fiber pulp is 18-28°SR.

8. The method for preparing reconstituted tobacco by papermaking according to any one of claims 1-7, characterized in that, The preparation method includes the following steps: (1) Tobacco fiber pulp, hardwood fiber pulp, calcium carbonate filler and molecular bond targeting ablative are mixed and stirred to obtain modified pulp; (2) Mix the modified slurry with the food-grade binder; (3) Then mix and stir with anti-caking loose modifier and bio-crosslinking flexible agent, and vacuum defoam to obtain mixed slurry; (4) The mixed slurry is formed into shape, and tobacco concentrated extract is coated on the surface of the wet substrate sheet after forming; (5) After coating, the tobacco leaves are dried to obtain reconstituted tobacco leaves.

9. The preparation method according to claim 8, characterized in that, The mixing and stirring in step (1) shall be carried out at 40-50℃ for 30-45 min; Preferably, the mixing and stirring in step (2) is carried out at 20-35°C for 10-20 min; Preferably, the mixing and stirring in step (3) is carried out at 40-45°C for 30-40 min; Preferably, the controlled quantitative amount in the copying process of step (4) is 55-58 g / m³. 2 ; Preferably, the coating control coating rate in step (4) is 39-40%.

10. The preparation method according to claim 8, characterized in that, The drying process described in step (5) employs a three-stage gradient drying method: First stage: Dry at 80-90℃ until moisture content is 17-20%; Second stage: Dry at 95-105℃ until moisture content is 13-15%; Third stage: Dry at 80-95℃ until the moisture content is 11-12%.

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