Treatment agent for reconstituted tobacco and reconstituted tobacco processing method

Abstract

The invention relates to the technical field of reconstituted tobacco, in particular to a treating agent for reconstituted tobacco and a reconstituted tobacco processing method. The treatment agent comprises a deep-eutectic solvent, and the deep-eutectic solvent takes polyglycerol as a hydrogen bond donor and takes at least one of betaine, sodium lactate and disodium dihydrogen pyrophosphate as a hydrogen bond receptor. According to the method, the reconstituted tobacco is processed by adopting the polyglycerol type eutecticevaporate solvent of the specific hydrogen bond receptor, so that the water holding capacity of the reconstituted tobacco under different temperature and humidity conditions is improved, particularly the water holding capacity of the reconstituted tobacco under the low-temperature drying condition is improved, and the water holding capacity reaches the tobacco level; and thus, the flavoring and charging uniformity of shred making is improved, and the product quality and the sensory evaluation quality of the product are improved. In addition, based on the matching of the characteristics of polyglycerol macromolecules and polyhydroxy, hydrogen bond acceptor electrostatic repulsion or / and permeation plasticizing characteristics or / and competitive cross-linking characteristics and the characteristics of the reconstituted tobacco, the tensile strength of the reconstituted tobacco can be reduced so as to be matched with the natural tobacco.

Description

Technical Field

[0001] This invention relates to the field of reconstituted tobacco technology, and more particularly to a reconstituted tobacco treatment agent and a reconstituted tobacco processing method. Background Technology

[0002] The water-holding capacity and physical strength of reconstituted tobacco have a significant impact on the tobacco processing, sensory taste, and cigarette structure.

[0003] Reconstituted tobacco leaves are often blended with natural tobacco leaves (by a ratio of approximately 1-2:8-9). However, differences between reconstituted and natural tobacco leaves affect their blending and processing effects. Compared to flue-cured tobacco leaves, which have a dense surface structure, small pores, and high oil content, reconstituted tobacco sheets have a loose surface structure, large pores, and low oil content. This results in increased fragmentation during cigarette processing and enhanced dryness and irritation during smoking, specifically affecting water retention, tensile strength, and sensory performance.

[0004] In terms of water retention capacity, the physical moisture retention performance of tobacco refers to the ability of tobacco leaves to regulate moisture loss when in a low-humidity environment. Reconstituted tobacco sheets have a lower water retention capacity than tobacco leaves. This is manifested in the fact that during heating, humidification, and processing, the sheets absorb less moisture and have lower moisture content than the leaves. It is also reflected in the fact that during storage and cooling, the sheets release moisture quickly and dry out easily, summarized as "not absorbing moisture and not retaining it." Sampling and testing on the cigarette-making line revealed a moisture difference of approximately 10% to 20% between the sheets and the leaves. In the cigarette-making process, moisture is a crucial performance indicator for each stage. The difference in moisture absorption and release between the sheets and the leaves reduces the overall moisture stability of the cigarette pack, affecting the uniformity of the processing (for example, the sheets are less likely to absorb and retain additives compared to the leaves, leading to uneven processing). Furthermore, because the sheets are not as good at retaining moisture and softness as the leaves, they may also affect the uniformity of cutting and blending the sheets and tobacco shreds. Currently, traditional humectants such as glycerin and propylene glycol are used, but it is still impossible to achieve the same water-holding capacity as natural tobacco leaves. In terms of sensory characteristics, reconstituted tobacco leaves exhibit noticeable off-flavors and irritation compared to natural tobacco leaves. Regarding tensile strength, reconstituted tobacco sheets have higher strength, but when blended with natural tobacco leaves, uneven shredding occurs, affecting the uniformity of cigarette component blending and filling rate.

[0005] Eutectic solvents (DESs) are considered green solvents due to their ease of synthesis, low cost, environmental friendliness, and biodegradability. By combining DESs through hydrogen bonding, they form eutectic mixtures. Due to the hydrogen bonding between natural DESs and water, they possess excellent water-retention properties. Patent document CN107136560A discloses a natural DES tobacco humectant, its preparation method, and its application. This humectant is prepared from the following components: 10%–50% natural DES, 0.1%–0.5% preservative, 0.1%–0.5% defoamer, and the balance being water, with a neutral pH. This humectant is used to retain moisture in tobacco leaves and shreds. However, when used in reconstituted tobacco, it still fails to adequately improve the water-holding capacity of the reconstituted tobacco and cannot adjust the tensile strength of the reconstituted tobacco. Summary of the Invention

[0006] The present invention aims to solve the above-mentioned problems by providing a reconstituted tobacco processing agent and a reconstituted tobacco processing method that can adjust the water-holding capacity, tensile strength, and sensory properties of reconstituted tobacco leaves to be compatible with natural tobacco leaves.

[0007] The technical solution to the problem of this invention is, firstly, to provide a treatment agent for reconstituted tobacco leaves, used for reconstituted tobacco leaves; the treatment agent includes a eutectic solvent, wherein the eutectic solvent uses polyglycerol as a hydrogen bond donor and at least one of betaine, sodium lactate, and disodium dihydrogen pyrophosphate as a hydrogen bond acceptor.

[0008] Although this invention also provides a eutectic solvent, the inventors have adjusted the hydrogen bond donor and hydrogen bond acceptor to enable the eutectic solvent to be used in reconstituted tobacco leaves, thereby improving the water-holding capacity of reconstituted tobacco leaves to reach the level of natural tobacco leaves, and thus improving the sensory performance of reconstituted tobacco leaves; at the same time, it unexpectedly reduces the tensile strength of reconstituted tobacco leaves, also bringing it to the level of natural tobacco leaves, so as to better match the tobacco leaf processing.

[0009] This primarily relies on a specific hydrogen bond donor. In this invention, polyglycerol is used as the hydrogen bond donor. Polyglycerol, with its large molecular weight and multiple hydroxyl groups, not only provides efficient moisture retention but also utilizes its large molecular weight to physically fill the pores of reconstituted tobacco leaves through steric hindrance, slowing down moisture loss channels. Its macromolecular characteristics complement the pore characteristics of reconstituted tobacco leaves. Precisely because of its large molecular size, it is difficult for it to enter the intact cell structure of natural tobacco leaves. Furthermore, polyglycerol, filling the pores of reconstituted tobacco leaves, partially replaces chemical binders and inserts itself between the cellulose fibers, weakening the tensile strength of the reconstituted tobacco sheet.

[0010] Secondly, hydrogen bond acceptors are used to enhance hydration and further weaken tensile strength to approximate natural tobacco leaves. For example, betaine has amphoteric properties and extremely high hydration capacity. Simultaneously, it fills the pores of reconstituted tobacco leaves with polyglycerol, generating electrostatic repulsion and reducing the bonding strength between cellulose molecules. Another example is sodium lactate, which provides strongly hydrated sodium ions. Sodium lactate molecules are small and highly polar, allowing them to penetrate the fiber pores of reconstituted tobacco leaves first, weakening the rigid hydrogen bonds between cellulose molecular chains and opening channels for subsequent larger polyglycerol molecules, promoting the uniform binding of polyglycerol to reconstituted tobacco leaves. Furthermore, disodium dihydrogen pyrophosphate provides hydrated sodium ions and pyrophosphate ion coordination sites. It can competitively chelate metal ions in reconstituted tobacco leaves, breaking the rigid cross-linking bonds between metal ions and cellulose, thus reducing tensile strength.

[0011] For hydrogen bond donors, the degree of polymerization of polyglycerol is preferably limited. If the polymerization is too low, there will be insufficient hydroxyl groups and insufficient molecular chain length; if the polymerization is too high, the viscosity will be high, it will be difficult to penetrate, and it will be easy to aggregate. As a preferred embodiment of the present invention, the degree of polymerization of the polyglycerol is 4 to 10. For example, the polyglycerol is selected from at least one of tetraglycerol, pentaglycerol, hexaglycerol, heptaglycerol, octaglycerol, nonaglycerol, and decaglycerol.

[0012] For hydrogen bond acceptors, different hydrogen bond acceptors are known to improve the bridging of polyglycerol and reconstituted tobacco in different ways.

[0013] As a preferred embodiment of the present invention, the hydrogen bond acceptor is composed of betaine, sodium lactate, and disodium dihydrogen pyrophosphate. The electrostatic repulsion of betaine, the internal plasticization of sodium lactate, and the competitive chelation of disodium dihydrogen pyrophosphate, the three components work synergistically and complementarily to further adjust the water-holding capacity and physical strength of reconstituted tobacco leaves.

[0014] Preferably, the molar ratio of betaine, sodium lactate, and disodium dihydrogen pyrophosphate is (1.5–2.5):(1.5–2.5):1. For example, when the molar amount of disodium dihydrogen pyrophosphate is 1 part, the molar amount of betaine can be 1.5 parts, 1.7 parts, 2.0 parts, 2.2 parts, or 2.5 parts, and the molar amount of sodium lactate can be 1.5 parts, 1.7 parts, 2.0 parts, 2.2 parts, or 2.5 parts.

[0015] As a preferred embodiment of the present invention, the treatment agent is prepared by the following steps:

[0016] S1. The hydrogen bond donor and hydrogen bond acceptor are mixed in a certain proportion to obtain a mixture;

[0017] S2. Mix the mixture at 50-80°C for 2-4 hours until a transparent liquid is formed to obtain the eutectic solvent;

[0018] S3. The eutectic solvent is diluted with a diluent to obtain the treatment agent; the diluent includes water.

[0019] In step S1, as a preferred embodiment of the present invention, the molar ratio of the hydrogen bond donor to the hydrogen bond acceptor is (1-4):1. Examples include 1:1, 2:1, 3:1, and 4:1; preferably 1:1.

[0020] In step S2, for example, the temperature can be 50℃, 55℃, 60℃, 65℃, 70℃, 75℃, or 80℃, and the mixing time can be 2h, 2.5h, 3h, 3.5h, or 4h, with "the formation of a transparent liquid" as the indicator of the completion of mixing.

[0021] In step S3, the eutectic solvent needs to be diluted before use. If the concentration is too high, the permeability of the treatment agent is poor; if the concentration is too low, a continuous reinforcing-wetting network cannot be formed, and uneven component distribution is likely to occur during the drying process. Preferably, the concentration of the eutectic solvent in the treatment agent is 3wt% to 7wt%. For example, the concentration can be 3wt%, 3.5wt%, 4wt%, 4.5wt%, 5wt%, 5.5wt%, 6wt%, 6.5wt%, or 7wt%.

[0022] The solvent used to dilute the eutectic solvent is not limited, but should not affect the smoking taste of the reconstituted tobacco. The diluent includes water, meaning it may contain only water, or it may include water and other additives or coating solutions suitable for reconstituted tobacco. The diluent can be water, a water-containing tobacco extract, etc. For example, the treatment agent consists of the eutectic solvent and water; or the treatment agent consists of the eutectic solvent and a tobacco extract, which may be derived from tobacco extract obtained during the reconstituted tobacco production process, and the density of the tobacco extract is preferably 1.1–1.2 g / cm³. 2 .

[0023] Secondly, another objective of this invention is to provide a method for processing reconstituted tobacco leaves, wherein the reconstituted tobacco leaves are obtained by coating a tobacco sheet base with a coating liquid and then drying; during processing, the reconstituted tobacco leaves are sprayed or coated with a treatment agent onto the reconstituted tobacco leaves or the tobacco sheet base.

[0024] Specifically, in some embodiments, the following steps are included: first, coating liquid is applied to tobacco leaf base and then dried to obtain reconstituted tobacco leaf; then, the eutectic solvent is diluted with water to obtain a treatment agent; finally, the treatment agent is sprayed onto the reconstituted tobacco leaf and dried to form a shape.

[0025] In other embodiments, the steps include: first, adding the eutectic solvent to the coating liquid to obtain a treatment agent; then, coating the treatment agent containing the eutectic solvent and the coating liquid onto the tobacco sheet base; and finally, drying to obtain reconstituted tobacco.

[0026] In this invention, a specific treatment liquid is uniformly sprayed onto the surface of reconstituted tobacco leaves, or added to a tobacco coating liquid and coated onto the surface of a tobacco sheet base, which can adjust the water-holding capacity and tensile strength of the reconstituted tobacco leaves to approximate those of natural tobacco leaves.

[0027] As mentioned above, the components in the treatment agent adjust the water retention capacity and tensile strength by interacting with the pores of the reconstituted tobacco leaves. Therefore, the structure of the reconstituted tobacco leaves themselves affects the processing effect of the treatment agent. Preferably, the reconstituted tobacco leaves are obtained through the following steps: extracting tobacco raw materials and water at a mass ratio of 1:(5-7) at 50-70°C for 35-45 minutes, followed by mechanical extrusion to separate the solid and liquid phases into a solid phase and an aqueous phase; preparing the solid phase into the tobacco sheet base; and concentrating the aqueous phase to a density of 1.1-1.2 g / cm³. 2 The coating solution is prepared; the coating solution is coated onto the tobacco sheet base at a coating rate of 36% to 38%. For example, the mass ratio of tobacco raw material to water can be 1:5, 1:5.5, 1:6, 1:6.5, or 1:7, preferably 1:6; the extraction temperature can be 50℃, 55℃, 60℃, 65℃, or 70℃, preferably 60℃; the extraction time can be 35 min, 37 min, 40 min, 42 min, or 45 min, preferably 40 min; and the concentration density of the aqueous phase can be 1.1 g / cm³. 2 1.13 g / cm 2 1.15g / cm 2 1.17g / cm 2 1.2g / cm 2 The preferred value is 1.15 g / cm³. 2 The coating rate can be 36%, 36.5%, 37%, 37.5%, or 38%.

[0028] Wherein, coating rate = (weight of product after coating - weight of tobacco sheet base before coating) / weight of product after coating.

[0029] The amount of treatment agent affects the processing effect. Too much treatment agent can make the reconstituted tobacco leaves soft and sticky, and can easily fill the pores of the reconstituted tobacco leaves. Although this may temporarily lock in moisture, it will seriously affect its air permeability and combustion performance. Too little treatment agent cannot be effectively inserted between the fibers, and the effects of moisture retention and reduction of tensile strength are not significant.

[0030] In the above-described spraying embodiments, as a preferred embodiment of the present invention, the amount of the eutectic solvent is 1 wt% to 5 wt% of the mass of the reconstituted tobacco leaves. For example, the amount can be 1 wt%, 2 wt%, 3 wt%, 4 wt%, or 5 wt%.

[0031] In the above-described coating embodiments, as a preferred embodiment of the present invention, the amount of the eutectic solvent is 3 wt% to 7 wt% of the mass of the coating liquid. For example, the amount may be 3 wt%, 4 wt%, 5 wt%, 6 wt%, or 7 wt%.

[0032] After spraying or coating, dry at 100-120℃ for 3-7 minutes. The drying temperature can be 100℃, 105℃, 110℃, 115℃, or 120℃; the drying time can be 3 minutes, 4 minutes, 5 minutes, 6 minutes, or 7 minutes.

[0033] The beneficial effects of this invention are:

[0034] 1. This invention provides a reconstituted tobacco processing agent and a reconstituted tobacco processing method. The reconstituted tobacco is processed using a polyglycerol-based eutectic solvent with specific hydrogen bond acceptors, improving its water retention capacity under different temperature and humidity conditions, especially under low-temperature drying conditions, bringing it to the level of natural tobacco leaves. This increases the water retention capacity of the reconstituted tobacco by more than 40%. This improves the uniformity of flavoring and additives in tobacco processing, enhancing product quality and sensory evaluation. Furthermore, the increased surface moisture of the reconstituted tobacco reduces its strength, allowing for better processing. Simultaneously, based on the characteristics of polyglycerol macromolecules and multiple hydroxyl groups, the electrostatic repulsion and / or penetrating plasticizing properties of hydrogen bond acceptors, and / or competitive cross-linking properties, combined with the characteristics of reconstituted tobacco, the tensile strength of the reconstituted tobacco can also be reduced to match that of natural tobacco leaves.

[0035] 2. The process of this invention is simple and highly operable. Detailed Implementation

[0036] The following are specific embodiments of the present invention, and the technical solutions of the present invention will be further described, but the present invention is not limited to these embodiments.

[0037] Reconstituted tobacco preparation

[0038] Tobacco raw materials were mixed with 60℃ hot water at a mass ratio of 1:6 and extracted for 40 minutes. After extraction, the material was separated into solid and liquid phases by mechanical extrusion. The obtained solid phase was processed into tobacco sheet base G through pulping and papermaking processes; the obtained aqueous phase was concentrated to a density of 1.15 g / cm³. 3 Obtain coating liquid Y.

[0039] With a coating rate of 37%, the coating liquid Y is evenly coated onto the tobacco sheet base G using a roller coating machine. After drying, the moisture is removed to obtain reconstituted tobacco leaf Z with a product moisture content of 12%.

[0040] Example 1

[0041] A reconstituted tobacco treatment agent is obtained through the following steps: 6 kg of betaine (hydrogen bond acceptor) and 1 kg of decaglycerol (hydrogen bond donor) are weighed at a molar ratio of 1:1 and placed in a 50°C water bath with stirring for 2 hours until a transparent liquid is formed, yielding a eutectic solvent. 105 kg of water is weighed at 15 times the mass of the eutectic solvent and diluted with the solvent at a water temperature of 20°C to obtain treatment agent A-1 with a concentration of 6.25%.

[0042] A method for processing reconstituted tobacco leaves includes the following steps: weighing 1 kg of the reconstituted tobacco leaf Z obtained above, and according to 1% of the mass of the reconstituted tobacco leaf Z, 0.01 kg of eutectic solvent is required, i.e., weighing 0.16 kg of treatment agent A-1, which is evenly sprayed onto the surface of the reconstituted tobacco leaf Z, and then dried at 100°C for 7 min to form a shape.

[0043] Example 2

[0044] A reconstituted tobacco treatment agent is obtained through the following steps: 4 kg of sodium lactate (hydrogen bond acceptor) and 1 kg of tetraglyceride (hydrogen bond donor) are weighed at a molar ratio of 1:1 and placed in a 60°C water bath with stirring for 3 hours until a transparent liquid is formed, yielding a eutectic solvent. 100 kg of water is weighed at 20 times the mass of the eutectic solvent and diluted with the solvent at 30°C to obtain treatment agent A-2 with a concentration of 4.76%.

[0045] A method for processing reconstituted tobacco leaves includes the following steps: weighing 1 kg of the reconstituted tobacco leaf Z obtained above, and according to 3% of the mass of the reconstituted tobacco leaf Z, 0.03 kg of eutectic solvent is required, i.e., weighing 0.63 kg of treatment agent A-2, and uniformly spraying it onto the surface of the reconstituted tobacco leaf Z, and then drying it at 110℃ for 5 min to form a shape.

[0046] Example 3

[0047] A reconstituted tobacco treatment agent is obtained through the following steps: 1 kg of disodium dihydrogen pyrophosphate (hydrogen bond acceptor) and 1 kg of hexaglycerol (hydrogen bond donor) are weighed at a molar ratio of 1:1 and placed in a 70°C water bath with stirring for 5 hours until a transparent liquid is formed, yielding a eutectic solvent. 60 kg of water is weighed at 30 times the mass of the eutectic solvent and diluted with the solvent at a water temperature of 50°C to obtain treatment agent A-3 with a concentration of 3.23%.

[0048] A method for processing reconstituted tobacco leaves includes the following steps: weighing 1 kg of the reconstituted tobacco leaf Z obtained above, and according to 5% of the mass of the reconstituted tobacco leaf Z, 0.05 kg of eutectic solvent is required, i.e., weighing 1.55 kg of treatment agent A-3, and uniformly spraying it onto the surface of the reconstituted tobacco leaf Z, and then drying it at 120℃ for 3 min to form a shape.

[0049] Example 4

[0050] A reconstituted tobacco treatment agent is obtained through the following steps: 6 kg of betaine (hydrogen bond acceptor) and 1 kg of decaglycerol (hydrogen bond donor) are weighed at a molar ratio of 1:1 and placed in a 50°C water bath with stirring for 2 hours until a transparent liquid is formed, yielding a eutectic solvent. 1 kg of the above-prepared coating solution Y is weighed, and 0.04 kg of the eutectic solvent is added to the coating solution Y at a mass of 4%, and the mixture is stirred until homogeneous, yielding a 4% treatment solution A-4.

[0051] A method for processing reconstituted tobacco leaves includes the following steps:

[0052] With a coating rate of 37%, the treatment liquid A-4 is evenly coated onto the tobacco sheet base G prepared above using a roller coater; after coating, the product is dried at 120°C for 3 minutes and then shaped.

[0053] Example 5

[0054] A reconstituted tobacco treatment agent is obtained through the following steps: 4 kg of sodium lactate (hydrogen bond acceptor) and 1 kg of tetraglyceride (hydrogen bond donor) are weighed at a molar ratio of 1:1 and placed in a 60°C water bath with stirring for 3 hours until a transparent liquid is formed, yielding a eutectic solvent. 1 kg of the above-prepared coating solution Y is weighed, and 0.06 kg of the eutectic solvent (6% of the mass of coating solution Y) is added to coating solution Y and stirred until homogeneous, yielding a 6% concentration treatment solution A-5.

[0055] A method for processing reconstituted tobacco leaves includes the following steps: applying a treatment liquid A-5 uniformly onto the tobacco leaf base G prepared above using a roller coater with a coating rate of 37%; and drying the coated product at 105°C for 5 minutes to form a finished product.

[0056] Example 6

[0057] This embodiment is basically the same as Embodiment 2, except that the eutectic solvent is different.

[0058] A reconstituted tobacco treatment agent is obtained through the following steps: betaine, sodium lactate, disodium dihydrogen pyrophosphate, and hexameric glycerol are mixed in a molar ratio of 0.4:0.4:0.2:1 and stirred in a 60°C water bath for 3 hours until a transparent liquid is formed, yielding a eutectic solvent. 100 kg of water is weighed at 20 times the mass of the eutectic solvent and diluted with the solvent at 30°C to obtain a 4.76% concentration treatment agent A-2.1.

[0059] A method for processing reconstituted tobacco leaves includes the following steps: weighing 1 kg of the reconstituted tobacco leaf Z obtained above, and according to 3% of the mass of the reconstituted tobacco leaf Z, 0.03 kg of eutectic solvent is required, i.e., weighing 0.63 kg of treatment agent A-2.1, which is evenly sprayed onto the surface of the reconstituted tobacco leaf Z, and then dried at 110℃ for 5 min to form a shape.

[0060] Blank example

[0061] The reconstituted tobacco leaf Z obtained above was selected.

[0062] Comparative Example 1

[0063] This comparative example is basically the same as Example 2, except that the treatment agent is an aqueous glycerol solution.

[0064] Weigh 1 kg of the reconstituted tobacco leaf Z prepared above, and 0.63 kg of a glycerol aqueous solution with a glycerol mass concentration of 4.76% (glycerol amount is 0.03 kg), spray it evenly on the surface of the reconstituted tobacco leaf Z, and then dry it at 110℃ for 5 min to form a shape.

[0065] Comparative Example 2

[0066] This comparative example is basically the same as Example 2, except that the eutectic solvent is different.

[0067] Sodium lactate and glycerol were mixed in a molar ratio of 1:1 and stirred in a 60°C water bath for 3 hours until a transparent liquid was formed, yielding a eutectic solvent. The eutectic solvent was diluted in 30°C water to obtain treatment agent A-2.2 with a eutectic solvent concentration of 4.76%.

[0068] Weigh 1 kg of the reconstituted tobacco leaf Z obtained above. According to the requirement of 0.03 kg of eutectic solvent for 3% of the mass of reconstituted tobacco leaf Z, we weigh 0.63 kg of treatment agent A-2.2 and spray it evenly on the surface of reconstituted tobacco leaf Z. Then dry it at 110℃ for 5 min and shape it.

[0069] Comparative Example 3

[0070] This comparative example is basically the same as Example 2, except that the eutectic solvent is different.

[0071] Choline chloride and polyglycerol were mixed in a molar ratio of 1:1 and stirred in a 60°C water bath for 3 hours until a transparent liquid was formed, yielding a eutectic solvent. The eutectic solvent was diluted in 30°C water to obtain treatment agent A-2.3 with a eutectic solvent concentration of 4.76%.

[0072] Weigh 1 kg of the reconstituted tobacco leaf Z obtained above. According to the requirement of 0.03 kg of eutectic solvent for 3% of the mass of reconstituted tobacco leaf Z, we weigh 0.63 kg of treatment agent A-2.3 and spray it evenly on the surface of reconstituted tobacco leaf Z. Then dry it at 110℃ for 5 min and shape it.

[0073] Comparative Example 4

[0074] This comparative example is basically the same as Example 4, except that the treatment agent is glycerol.

[0075] Weigh 1 kg of the coating solution Y prepared above, weigh 0.04 kg of glycerin and add it to the coating solution Y, stir evenly to obtain a 4% concentration of contrast agent. According to the coating rate of 37%, use a roller coater to evenly coat the contrast agent onto the tobacco sheet base G prepared above; after coating, the product is dried at 120℃ for 3 minutes and then shaped.

[0076] Detection

[0077] The water-holding capacity of the reconstituted tobacco leaves obtained in the examples, blank examples, and comparative examples under different conditions was tested, and the test results are shown in Table 1 below. Wherein, water-holding capacity W = (m2-m1) / (m2-m0)×100%, m0 is the mass of the weighing dish (g); m1 is the total mass of the weighing dish and sample before the test (g); m2 is the total mass of the weighing dish and sample after the test (g). W is the moisture content; the higher the W, the better the moisture retention effect.

[0078] Table 1. .

[0079] As shown in Table 1, compared to the conventional reconstituted tobacco leaves without humectants such as glycerin and propylene glycol in the blank examples, the reconstituted tobacco leaves sprayed or coated with eutectic solvents in Examples 1-5 showed increases in water holding capacity of 15.67%–98.42%, 16.69%–92.23%, 16.44%–80.22%, 20.69%–93.33%, and 12.83%–79.13% under different temperature and humidity conditions, respectively. Compared to the reconstituted tobacco leaves sprayed or coated with glycerin humectant in Comparative Examples 1 and 4, at the same dosage, the reconstituted tobacco leaves sprayed with eutectic solvents in Examples 2 and 4 showed increases in water holding capacity of 5.04%–16.53% and 5.07%–19.41% under different temperature and humidity conditions, respectively. These findings demonstrate the improvement in water holding capacity of reconstituted tobacco leaves by eutectic solvents. Continuing with the comparison between Example 2 and Comparative Example 2, it is evident that the polyglycerol-based eutectic solvent has a better effect on improving the water-holding capacity of reconstituted tobacco leaves compared to conventional glycerol-based eutectic solvents. This may be because polyglycerol, with its large molecular weight and multiple hydroxyl characteristics, has better compatibility with reconstituted tobacco leaves. Comparing Example 2 and Comparative Example 3, it is evident that the selection of hydrogen bond acceptors in the eutectic solvent also has a certain impact on improving the water-holding capacity of reconstituted tobacco leaves. Compared to sodium lactate, choline chloride lacks strong ionic hydration and has insufficient water-locking capacity.

[0080] Sensory evaluations were performed on the reconstituted tobacco leaves obtained in the examples, blank examples, and comparative examples. The results are shown in Table 2 below.

[0081] Table 2. experimental group Sensory evaluation total score Example 1 88.5 Example 2 88.6 Example 3 88.9 Example 4 89.2 Example 5 88.8 Example 6 89.3 Blank example 85.5 Comparative Example 1 86.2 Comparative Example 2 86.7 Comparative Example 3 86.1 Comparative Example 4 86.6 .

[0082] As shown in Table 2, compared to the blank example, Comparative Example 1, and Comparative Example 4, the eutectic solvent treatment in the examples improved the sensory quality of reconstituted tobacco. Further comparison of Example 2 and Comparative Examples 2 and 3 shows that the composition of the eutectic solvent also affects the sensory quality of reconstituted tobacco. In Comparative Example 2, the glycerol-type eutectic solvent had limited effect on improving the water-holding capacity of the reconstituted tobacco, resulting in insufficient moisture, some off-flavors, and irritation. In Comparative Example 3, choline chloride may decompose at high temperatures, producing off-flavors that negatively impact the aroma and comfort of cigarette smoking.

[0083] The tensile strength of the reconstituted tobacco leaves obtained in the examples, blank examples and comparative examples was tested according to GB / T 12914 Determination of Tensile Strength of Paper and Paperboard, which is recommended in YC / T16-2014 Reconstituted Tobacco Leaves. The test results are shown in Table 3 below.

[0084] Table 3. experimental group Tensile strength (kN / m) Example 1 0.57 Example 2 0.52 Example 3 0.56 Example 4 0.49 Example 5 0.54 Example 6 0.46 Blank example 0.72 Comparative Example 1 0.68 Comparative Example 2 0.63 Comparative Example 3 0.65 Comparative Example 4 0.62 .

[0085] As shown in Table 3, comparing the examples, blank examples, and comparative examples 1 and 4, it can be seen that the polyglycerol-type eutectic solvent with specific hydrogen bond acceptors used in the embodiments of the present invention can reduce the tensile strength of reconstituted tobacco leaves compared to untreated reconstituted tobacco leaves and glycerol-treated reconstituted tobacco leaves, making them compatible with natural tobacco leaves. Further comparing Example 2 and comparative examples 2 and 3, it can be seen that the components of the eutectic solvent also affect the tensile strength of reconstituted tobacco leaves. In comparative example 2, glycerol is a short-chain small molecule and cannot form a continuous flexible membrane, while in comparative example 3, choline chloride lacks deep decrosslinking ability; both of these affect the reduction effect on tensile strength.

[0086] The specific embodiments described herein are merely illustrative of the spirit of the invention. Those skilled in the art to which this invention pertains may make various modifications or additions to the described specific embodiments or use similar methods to substitute them, without departing from the spirit of the invention or exceeding the scope defined by the appended claims.

Claims

1. A treating agent for reconstituted tobacco leaves, characterized by: The processing agent for reconstituted tobacco leaf; the processing agent comprises a deep eutectic solvent, the deep eutectic solvent takes polyglycerol as a hydrogen bond donor, and takes at least one of betaine, sodium lactate, and disodium hydrogen pyrophosphate as a hydrogen bond acceptor.

2. The processing agent for reconstituted tobacco leaf according to claim 1, characterized by: The polyglycerol is at least one of tetraglycerol, pentaglycerol, hexaglycerol, heptaglycerol, octaglycerol, nonaglycerol, and decaglycerol.

3. The treating agent for reconstituted tobacco leaf according to claim 1, characterized by: The hydrogen bond acceptor is composed of betaine, sodium lactate, and disodium hydrogen pyrophosphate.

4. The processing agent for reconstituted tobacco leaf according to claim 1, characterized by: The molar ratio of the hydrogen bond donor and the hydrogen bond acceptor is (1-4):

1.

5. The processing agent for reconstituted tobacco leaf according to claim 1, wherein: The concentration of the deep eutectic solvent in the processing agent is 3wt%-7wt%.

6. The processing agent for reconstituted tobacco leaf according to claim 1 or 4 or 5, characterized in that: The processing agent is prepared by the following steps: S1. The hydrogen bond donor and the hydrogen bond acceptor are mixed in proportion to obtain a mixture; S2. The mixture is mixed at 50-80℃ for 2-4h until a transparent liquid is formed to prepare the deep eutectic solvent; S3. The deep eutectic solvent is diluted with a diluent to prepare the processing agent; the diluent comprises water.

7. A processing method for reconstituted tobacco leaf, characterized in that: The reconstituted tobacco leaf is obtained by coating a tobacco sheet base with a coating liquid and then drying; During processing, the processing agent for reconstituted tobacco leaf according to any one of claims 1-6 is sprayed or coated on the reconstituted tobacco leaf or the tobacco sheet base.

8. The processing method for reconstituted tobacco leaf according to claim 7, characterized in that: The reconstituted tobacco leaf is obtained by the following steps: After tobacco raw material and water are extracted at a mass ratio of 1:(5-7) at 50-70℃ for 35-45min, solid-liquid separation is performed by mechanical extrusion to obtain a solid phase and an aqueous phase; The solid phase is made into the tobacco sheet base, and the aqueous phase is concentrated to a density of 1.1-1.2 g / cm 2 The coating liquid is prepared; The coating liquid is coated on the tobacco sheet base at a coating rate of 36%-38%.

9. The processing method for reconstituted tobacco leaf according to claim 8, characterized in that: The amount of the deep eutectic solvent is 1wt%-5wt% of the mass of the reconstituted tobacco leaf; Or, the amount of the deep eutectic solvent is 3wt%-7wt% of the mass of the coating liquid.

10. The method of processing reconstituted tobacco leaf according to claim 7, wherein: After spraying or coating, drying is performed at 100-120℃ for 3-7min.