WO2025181881A1 - Tobacco composition, non-combustion heating type smoking article, and method for storing tobacco composition - Google Patents

Abstract

The present invention addresses the problem of providing a stored tobacco composition comprising dried leaf tobacco obtained through drying so as to exhibit green color, in which discoloration during storage is suppressed. This tobacco composition is obtained by storing, for 50 days or longer under one or more of the following conditions (1) to (3), a tobacco composition before storage including first dried leaf tobacco obtained through drying so as to exhibit green color. (1) The tobacco composition before storage is stored at a water content of 10% by weight or less. (2) The tobacco composition before storage is stored in a light-shielding environment. (3) The tobacco composition before storage is stored at 40°C or lower.

Description

Tobacco composition, non-combustion heating smoking article, and method for storing tobacco composition

The present invention relates to a tobacco composition, a non-combustion heating smoking article, and a method for preserving a tobacco composition.

In non-combustible smoking articles, flavor components are generally distilled and delivered along with the aerosol by heating the tobacco rod to approximately 150°C to 350°C. In other words, for non-combustible smoking articles, a tobacco raw material that effectively expresses flavor and aroma in the temperature range of 150°C to 350°C is desired.

The tobacco raw materials used in non-combustible smoking articles are generally those that have traditionally been used in combustible tobacco. Known tobacco raw materials are classified into several types, including Virginia, Burley, and Orient. Virginia is a tobacco raw material with a rich aroma and is often used in combustible tobacco products known as Virginia Blends. Burley has a strong flavor and is used in combustible tobacco products known as American Blends. Orient has a distinctive flavor and can balance the taste and aroma of the entire blend.

The quality of the above raw materials is largely determined by the variety and cultivation method, but also by post-harvest processing methods, such as curing. Over the long history of tobacco culture, curing methods tailored to each variety have been thoroughly researched, and today, drying methods suitable for each variety have been established. After harvest, Virginia varieties undergo a process called flue-curing. That is, they are dried for 5 to 7 days in a temperature- and humidity-controlled environment, generally with the temperature gradually increased to 30 to 70°C (Non-Patent Documents 1 and 2). After harvest, Burley varieties undergo a process called air-curing. That is, they are dried for 30 to 40 days at natural ambient temperature, away from direct sunlight (Non-Patent Document 3). After harvest, Orient varieties are dried in the shade for one day, then exposed to sunlight for a process called sun/air-curing. Depending on the variety, they may then undergo a fermentation process (Non-Patent Document 4).

As such, the drying methods and conditions for leaf tobacco vary greatly depending on the variety. The appearance quality also differs depending on the variety, with differences in curing being a factor. For example, dried Virginia varieties are yellowish brown. Dried Burley varieties are deep brown. Dried Oriental varieties vary further depending on the cultivar, but are slightly greenish brown.

In the United States, scientific elucidation of quality changes during curing was undertaken between the 1930s and 1950s. This was summarized in a review by Frankenburg et al. (Non-Patent Document 5). It is believed that changes during the early stages of curing are primarily due to changes caused by plant respiration and, after cell death, changes in chemical components due to residual enzyme activity. Typical changes in components include protein hydrolysis, which is accompanied by increases in some amino acids and soluble nitrogen components such as ammonia (Non-Patent Document 6). Starch is hydrolyzed and converted into monosaccharides and other low-molecular-weight sugars (Non-Patent Document 2). These reactions occur due to the loss of the counterbalance that would normally occur in growing tobacco leaves. In other words, the metabolism of these components is fundamentally different from that during growth. Simultaneously with the hydrolysis reaction, various components are also changed by oxidation. As curing progresses, the dynamic equilibrium of the redox system inherent in living plants is lost, resulting in significant oxidation of many of the components in tobacco leaves. Carbohydrates and organic acids are oxidized under the influence of a series of enzymes previously involved in the respiratory system in living organisms (Non-Patent Documents 7 and 8). Additionally, phenolic and polyphenolic compounds and terpenoid compounds are also decomposed by oxidation (Non-Patent Documents 9-11). As mentioned above, there are several methods for curing tobacco depending on the variety and purpose. Among these, air-curing actively induces oxidation reactions of chemical components. On the other hand, fluid-curing is designed to minimize the effects of oxidation.

Peedin, G. F.: Production practices: Flue-cured tobacco, p. 104-142. In Tobacco: Production Chemistry and Technology, Davis, D. L., Nielsen, M. T., Eds.; Blackwell Science: Oxford, U.K. (1999) Abubakar, Y., Young, J. H., Johnson, W. H., and Weeks, W. W.: Changes in moisture and chemical composition of flue-cured tobacco during curing. Tob. Sci., 44, 51-58 (2000) Palmer, G. K., and Pearce, R. C.: Production practices: Light air-cured tobacco, p. 143-153. In Tobacco: Pro duction Chemistry and Technology, Davis, D. L., Nielsen, M. T., Eds.; Blackwell Science: Oxford, U.K. (1999) Gilchrist, S. N.: Production practices: Oriental tobacco, p. 154-163. In Tobacco: Production Chemistry and Technology, Davis, D. L., Nielsen, M. T., Eds.; Blackwell Science: Oxford, U.K. (1999) Frankenburg, W. G.: Chemical Changes in the Harvested Tobacco Leaf. I. Chemical and Enzymatic Conversations during the Curing Process. Advances in Enzymolozy, Volume VI, 6, 309-387 (1946) Young, J. R., and Jeffrey, R. N.: Changes in certain water-soluble nitrogenous constituents of burley tobacco during storage. Plant Plysiol., 18, 433-438 (1943) Pucher, G. W., and Vickery, H. B.: The metabolism of the organic acids of tobacco leaves; effect of culture of excised leaves in solutions of organic acid salts. J. Biol. Chem., 178, 557-575 (1949) Vickert, H. B., and Abrahams, M. D.: The metabolism of the organic acids of tobacco leaves; effect of culture of excised leaves in solutions of d-isocitrate and acetate. J. Biol. Chem., 180, 37-45 (1949) Sheen, S. J., and Calvert, J.: Studies on polyphenol content, activities and isozymes of polyphenol oxidase and peroxidase during air-curing in three tobacco types. Plant Physiol., 44, 199-204 (1969) Weston, T. J.: Biochemical characteristics of tobacco leaves during flue-curing. Phytochemistry, 7, 921-930 (1968) Wahlberg, I., Kerstin, K., Austin, D. J., Junker, D., Roeraade, J., Enzell, C. R., and Johnson, W. H.: Effects of flue-cu ring and aging on the volatile, neutral and acidic constituents of Virginia tobacco. Phytochemistry, 16, 1217-1231 (1977)

Based on a long history of research and experience, the technique of adjusting the drying process of tobacco leaves to produce dried leaves of the desired quality, known as curing technology, has been passed down to the present day. However, this quality is based on the assumption that the material will be used in combustible smoking articles, and is not necessarily optimal for non-combustible smoking articles. Conversely, even materials that are considered unsuitable for combustible smoking articles may have unexpected effects when used in non-combustible smoking articles.

By drying harvested tobacco leaves under specific conditions that avoid the browning that inevitably occurs with conventional curing methods, it is possible to obtain green-colored dried tobacco leaves. The inventors have discovered that when this green-colored dried tobacco leaf is applied to non-combustible smoking articles, it is possible to impart a natural green note that is not found in tobacco raw materials that have been used traditionally.

Methods for obtaining green-colored cured tobacco leaves include freeze-drying harvested tobacco leaves and drying using microwaves. Green-colored cured tobacco leaves can also be obtained by subjecting tobacco leaves to a heat treatment (blanching) using hot water or steam, followed by natural drying, freeze-drying, convection drying, contact drying, or radiant heat drying. The key to drying is to dry the tobacco leaves under conditions that make it difficult for enzyme reactions to occur or that shorten the reaction time, so that the green pigments contained in the tobacco leaves are not decomposed during drying. Green-colored cured tobacco leaves can be obtained by drying the tobacco leaves under conditions that make it difficult for enzyme reactions to occur or that shorten the reaction time.

However, it has been found that dried tobacco leaves, obtained by drying to retain a green color, are prone to discoloration during storage. Discoloration of dried tobacco leaves is a quality change, and it is desirable to suppress discoloration during storage.

In light of these circumstances, the present invention aims to provide a tobacco composition containing dried leaf tobacco obtained by drying to exhibit a green color, a stored tobacco composition in which discoloration during storage is suppressed, a non-combustion heat-type smoking article containing the tobacco composition, and a method for storing the tobacco composition.

The inventors have discovered that the above-mentioned problems can be solved by the following invention.

[1] A tobacco composition obtained by storing a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying to present a green color under one or more of the following conditions (1) to (3) for 50 days or more.
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below.

[2] The tobacco composition according to [1], wherein the first dried leaf tobacco has an a ^* value of -2 or less as measured according to the L ^* a ^* b ^* method standardized in CIE 1976.

[3] The tobacco composition described in [1] or [2], wherein the drying step comprises placing the harvested fresh leaves in an environment of 45°C or less until the moisture content of the mesophyll is 25% by weight or less.

[4] The drying is performed by placing the harvested fresh leaves in an environment of 30 to 40 ° C and a relative humidity of 60 to 70% for 6 to 12 hours, and then
The tobacco composition according to any one of [1] to [3], further comprising a step of placing the tobacco composition in an environment of 45°C or less until the moisture content of the mesophyll portion is reduced to 25% by weight or less.

[5] The tobacco composition according to any one of [1] to [4], wherein the first dried leaf tobacco is produced by extracting only the mesophyll portion when the moisture content of the mesophyll portion during the drying process reaches 12% by weight or less.

[6] The tobacco composition according to any one of [1] to [5], wherein the condition (1) is a condition in which the tobacco composition before storage is stored at a moisture content of 7% by weight or less.

[7] The tobacco composition described in any one of [1] to [6], wherein the tobacco composition before storage further contains at least one selected from the group consisting of glycerin, 1,2-propylene glycol, and 1,3-propylene glycol.

[8] The tobacco composition described in [7], wherein the tobacco composition before storage further contains glycerin.

[9] The tobacco composition according to [7] or [8], wherein the content of at least one substance selected from the group consisting of glycerin, 1,2-propylene glycol, and 1,3-propylene glycol contained in 100% by weight of the tobacco composition before storage is 5 to 30% by weight.

[10] The tobacco composition according to any one of [1] to [9], wherein the content of the first dried leaf tobacco contained in 100% by weight of the tobacco composition before storage is 30 to 95% by weight.

[11] The tobacco composition described in any one of [1] to [10], wherein the tobacco composition before storage further contains an aerosol source other than glycerin, 1,2-propylene glycol, and 1,3-propylene glycol.

[12] The tobacco composition described in any one of [1] to [11], wherein the pre-storage tobacco composition further contains reconstituted tobacco.

[13] The tobacco composition according to [12], wherein the content of the reconstituted tobacco in 100% by weight of the tobacco composition before storage is 5 to 85% by weight.

[14] The tobacco composition described in any one of [1] to [13], wherein the tobacco composition before storage further contains a second dried leaf tobacco other than the first dried leaf tobacco.

[15] The tobacco composition according to [14], wherein the content of the second dried leaf tobacco contained in 100% by weight of the tobacco composition before storage is 5 to 85% by weight.

[16] The tobacco composition described in any one of [1] to [15], wherein the tobacco composition before storage further contains a non-tobacco flavoring material.

[17] The tobacco composition described in [16], wherein the non-tobacco flavoring material is selected from the group consisting of flavorings, cooling agents, and combinations thereof.

[18] The tobacco composition described in [17], wherein the flavoring is menthol.

[19] A non-combustion heating smoking article comprising the tobacco composition described in any one of [1] to [18].

[20] A method for preserving a tobacco composition, comprising a step of preserving a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying so as to present a green color, for 50 days or more under one or more of the following conditions (1) to (3):
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below.

The present invention provides a tobacco composition containing dried leaf tobacco obtained by drying to exhibit a green color, a stored tobacco composition in which discoloration during storage is suppressed, a non-combustion heat-type smoking article containing the tobacco composition, and a method for storing the tobacco composition.

FIG. 1 is a diagram showing one embodiment of a non-combustion heating type smoking article. FIG. 1 is a diagram showing one embodiment of a non-combustion heating smoking system. FIG. 2 is a diagram illustrating an example of a first method for producing dried leaf tobacco. 1 is a graph showing the initial slope Δa ^* versus moisture content in Examples 1 to 5. 1 is a graph showing the a ^* value versus storage period in Examples 6 to 13. 1 is a graph showing the change in a ^* value with respect to the storage period in Examples 14 and 15. 1 is a graph showing the change in a ^* value with respect to the storage period in Examples 16 to 19. 1 is a graph showing the a ^* value versus storage period in Examples 20 to 22.

[Tobacco composition]
The tobacco composition of this embodiment is obtained by storing a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying to exhibit a green color under one or more of the following conditions (1) to (3) for 50 days or more.
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below.

The inventors have discovered that storing a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying to exhibit a green color under one or more of the conditions (1) to (3) above suppresses discoloration of the first dried leaf tobacco during storage. Storing the pre-storage tobacco composition at a moisture content of 10% by weight or less, as in condition (1), suppresses the formation of a reaction field that causes a decomposition reaction of the green pigment. It is therefore believed that discoloration of the first dried leaf tobacco is suppressed. Furthermore, storing the pre-storage tobacco composition in a light-blocking environment, as in condition (2), suppresses the decomposition of the green pigment due to a photoreaction. It is therefore believed that discoloration of the first dried leaf tobacco is suppressed. Furthermore, storing the pre-storage tobacco composition at 40°C or below, as in condition (3), slows the rate of the above-mentioned reaction. It is therefore believed that discoloration of the first dried leaf tobacco is suppressed. The tobacco composition according to this embodiment is a stored tobacco composition obtained by storing the pre-storage tobacco composition for 50 days or more under one or more of the conditions (1) to (3) above. Therefore, even though the tobacco composition has been stored for 50 days or more, discoloration of the first dried leaf tobacco contained in the tobacco composition is suppressed and the green color is sufficiently maintained. In other words, the quality of the tobacco composition according to this embodiment is sufficiently maintained.

The tobacco composition before storage may be stored for 50 days or more under conditions satisfying condition (1), or may be stored for 50 days or more under conditions satisfying condition (2), or may be stored for 50 days or more under conditions satisfying condition (3), or may be stored for 50 days or more under conditions satisfying conditions (1) and (2), or may be stored for 50 days or more under conditions satisfying conditions (1) and (3), or may be stored for 50 days or more under conditions satisfying conditions (2) and (3), or may be stored for 50 days or more under conditions satisfying conditions (1), (2), and (3). The storage period is not particularly limited as long as it is 50 days or more, but can be 75 days or more, or can be 100 days or more. The upper limit of the storage period is not particularly limited, but can be, for example, 730 days or less.

(First Dry Tobacco)
The first dried leaf tobacco according to this embodiment is obtained by drying harvested tobacco leaves (fresh leaves) so that they are green. By drying the harvested tobacco leaves so that they are green, it is possible to avoid a decrease in components suitable for non-combustible smoking articles. The first dried leaf tobacco may be the dried leaves themselves, or the mesophyll portion separated from the dried leaves.

The color tone, etc., of the first dry leaf tobacco is not limited as long as it is within a range that can be visually recognized as green. However, in one embodiment, the a ^* value of the first dry leaf tobacco measured according to the L ^* a ^* b ^* method standardized in CIE 1976 is preferably −2 or less. The ^{a *} value is more preferably −4 or less. The lower limit of the a* value is not limited, but can be, for example, −14 or more, −10 or more, or −8 or more. The ^a* value corresponds to a position between magenta and green, with a larger value being closer to magenta and a smaller value being closer to green.

The L ^* value, a ^* value, and b ^* value can be measured on the surface of tobacco leaves using a spectrophotometer (e.g., KONICA MINOLTA/CM3500d, Konica Minolta Holdings, Inc.). Specifically, the a ^* value and other values are determined by irradiating the surface of tobacco leaves with standard light (standard illuminant D65 for colorimetry, CIE, ISO reference light) and measuring the reflected light (reflected color measurement/specular reflection excluded method (SCE)). Color definitions comply with the International Commission on Illumination (CIE) and JIS.

In one embodiment, a component suitable for non-combustible smoking articles (hereinafter also referred to as "component H") is a component having a retention index (RI) of 1800 to 3100 in gas chromatography. Component H expresses the original aroma of tobacco. Component H is a component group including partial decomposition products of chlorophyll, leaf resin, higher fatty acids, and higher hydrocarbons. Specifically, component H includes neophytadiene (RI = 1842), phytol (RI = 2114), α-cembratriene diol (α-CBT, RI = 2242), linoleic acid (RI = 2145), etc. On the other hand, a component having an RI of 1365 or more and less than 1800 (hereinafter also referred to as "component L") is a component group including cembratriene decomposition products and carotenoid decomposition products. Component L includes 3-oxo-α-ionone (RI=1648), solanone (RI=1368), norsolanadione (RI=1489), megastigmatrienone (RI=1581), etc.

RI can be determined by known methods using standard saturated alkane standards, but is preferably determined by the following method.
1) Standard saturated alkane standards (for example, C7-C40 manufactured by Merck) are diluted with hexane to use hexane (C6) to tetracontane (C40) as indicators.
2) The linear retention index is calculated based on the following formula and is defined as RI.
RI = 100 × {[(tr(unknown) - tr(n)] / [tr(N) - tr(n)] + n}
n = number of carbon atoms in the n-alkane eluting immediately before the unknown component N = number of carbon atoms in the n-alkane eluting immediately after the unknown component tr = retention time

The first dried leaf tobacco is preferably Nicotiana tabacum, and more preferably Burley. Burley has a low sugar content, which reduces the generation of a cereal-like aroma. Non-combustion heated smoking articles emit a distinctive cereal-like aroma when in use. It is preferable to suppress this aroma. One of the causes of the cereal-like aroma is glycolysis. When heated, sugar generates pyrolysis components, typified by furans. In other words, if the sugar content in the first dried leaf tobacco is high, the cereal-like aroma can increase. During the drying process of fresh leaves, catabolic metabolism occurs, increasing sugars, which can result in the generation of a cereal-like aroma. However, using burley can suppress the cereal-like aroma.

(First method for producing dried tobacco)
The first cured leaf tobacco according to this embodiment is obtained by drying fresh leaves after harvesting under conditions that result in a green color. However, drying fresh leaves at a high temperature from the beginning tends to result in browned cured leaf tobacco. The reason for this is not limited, but sudden exposure to high temperatures destroys the cells of the fresh leaves, causing an enzyme that oxidizes component H in the fresh leaves to leak out of the cells. It is presumed that the enzyme reacts with component H, resulting in the oxidation of component H. Therefore, it is preferable to perform drying in stages.

In one aspect, the drying preferably includes a step of placing fresh leaves in an environment of 45°C or below until the moisture content of the mesophyll portion is reduced to 25% by weight or below (low-temperature drying step). Drying at such a low temperature prevents cell destruction in the fresh leaves, making component H less likely to oxidize and brown. The upper limit of the target moisture content of the mesophyll portion (hereinafter also referred to as "target moisture content") is preferably 20% by weight or below. The lower limit of the target moisture content is not limited, but is preferably 15% by weight or above. The lower limit of the temperature is not limited, but is preferably 35°C or above from the standpoint of work efficiency, etc. The humidity in the low-temperature drying step is not limited, but is preferably 30-40% relative humidity (30-40% RH).

It is preferable to carry out a process (high-temperature drying process) in which the dried tobacco leaves obtained in the low-temperature drying process are dried in an environment of 65-75°C and 15-25% RH to reduce the moisture content of the vein portion to 12% by weight or less. This embodiment is shown in Figure 3 (1). The high-temperature drying process exposes the mesophyll and vein portions to high temperatures, but because moisture has already been removed from the mesophyll portion, the enzymatic oxidation reaction of component H and browning are suppressed. The upper limit of the target moisture content in this process can be set to 10% by weight or less. However, because excessive drying may induce decomposition of component H, the lower limit of the moisture content of the vein portion is preferably 8% by weight or more. The temperature is preferably 67-70°C. The humidity is preferably 17-23% RH.

After this process, the mesophyll and vein portions may be separated, and the mesophyll portion may be used as the first dried leaf tobacco. By using the mesophyll portion as the first dried leaf tobacco when the moisture content of the vein portion is reduced to 12% by weight or less in this way, it is possible to prevent decay and deterioration of the leaf tobacco due to moisture remaining in the vein portion during processes after the leaf tobacco is unloaded, such as packaging, storage, and distribution.

The dried tobacco leaves obtained in the high-temperature drying process are preferably conditioned. There are no restrictions on the conditions for conditioned humidity, but a temperature of 20-25°C and a relative humidity of 50-70% are preferred. Conditioning the humidity helps prevent the tobacco leaves from being crushed during unloading and packaging. From this perspective, the temperature is preferably 21-23°C. The humidity is preferably 55-65% relative humidity. A preferred embodiment that includes this conditioned humidity process is shown in Figure 3 (2).

Before the low-temperature drying process, a process (pretreatment process) may be carried out in which the fresh leaves are conditioned for 6 to 12 hours at a temperature of 30 to 40°C and a relative humidity of 60 to 70%. Pretreatment can further suppress the changes in components caused by cell destruction mentioned above. From this perspective, the temperature is preferably 32 to 38°C. The humidity is preferably 62 to 67% relative humidity. A preferred embodiment that includes this conditioned humidity process is shown in Figure 3 (3).

(Tobacco composition before storage)
The tobacco composition before storage is not particularly limited as long as it contains first dry leaf tobacco. The content of the first dry leaf tobacco contained in 100% by weight of the tobacco composition before storage is preferably 30 to 95% by weight, and more preferably 50 to 90% by weight. The tobacco composition before storage may consist of the first dry leaf tobacco. That is, the content of the first dry leaf tobacco contained in 100% by weight of the tobacco composition before storage may be 100% by weight.

It is preferable that the tobacco composition before storage further contains a polyol in addition to the first dried leaf tobacco. By including a polyol in the tobacco composition before storage, discoloration of the first dried leaf tobacco during storage is further suppressed. Examples of polyols include glycerin, diglycerin, triglycerin, polyglycerin, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, polypropylene glycol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,2-hexanediol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, polyoxyethylene glycerin ether, isoprene glycol, pentaerythritol, trimethylolpropane, etc. Furthermore, sugar alcohols and sugars may also be used. Examples of sugar alcohols include sorbitol, inositol, glucosyltrehalose, xylitol, erythritol, mannitol, lactitol, fructose, oligosaccharide alcohols, maltitol, reduced palatinose, reduced starch syrup, and reduced starch hydrolysates. Examples of sugars that can be used include fructose, glucose, lactose, xylose, psicose, maltose, starch syrup, oligosaccharides, maltose, trehalose, lactose, palatinite, sucrose, isomerized sugars, isomaltooligosaccharides, fructooligosaccharides, galactooligosaccharides, xylooligosaccharides, lactoferrin oligosaccharides, soybean oligosaccharides, raffinose, and sucralose. These may be used alone or in combination.

Among these, it is preferable that the tobacco composition contains at least one compound selected from the group consisting of glycerin, 1,2-propylene glycol (1,2-propanediol), and 1,3-propylene glycol (1,3-propanediol) (hereinafter also referred to as compound A). When the tobacco composition before storage contains compound A, discoloration of the first dried leaf tobacco during storage is particularly suppressed. Glycerin is particularly preferred as compound A. When the tobacco composition before storage contains compound A, the content of compound A contained in 100% by weight of the tobacco composition before storage is preferably 5 to 70% by weight, and more preferably 10 to 50% by weight.

While Compound A also serves as an aerosol source, the tobacco composition before storage can also contain an aerosol source other than Compound A. The aerosol source is a material that vaporizes when heated and cools to generate an aerosol, or that generates an aerosol by atomization. When the tobacco composition contains an aerosol source, a sufficient amount of smoke can be achieved. Examples of aerosol sources include glycerin, vegetable glycerin, polyhydric alcohols such as propylene glycol (PG) and 1,3-propanediol, triethyl citrate (TEC), and triacetin. The content of the aerosol source (Compound A + aerosol source other than Compound A) contained in 100% by weight of the tobacco composition before storage is preferably 5 to 70% by weight, more preferably 8 to 30% by weight. If the amount of the aerosol source exceeds the upper limit, stains may occur on the tobacco segments, while if it is below the lower limit, the perceived smoke intensity may decrease.

The tobacco composition before storage can contain tobacco materials other than the first dry leaf tobacco. Such tobacco materials are not limited as long as they are derived from Nicotiana plants. Specific examples include tobacco shreds, tobacco powder, tobacco sheets, and strands, which are commonly used in the field. These can be used alone or in combination. Of these, reconstituted tobacco and second dry leaf tobacco other than the first dry leaf tobacco (ordinary dry leaf tobacco other than the first dry leaf tobacco) are preferred from the perspective of maintaining a balance of flavor and flavor. Reconstituted tobacco refers to tobacco that has been reconstituted by mixing tobacco components with other materials.

As leaf tobacco for use in tobacco materials other than the first dried leaf tobacco, species of the genus Nicotiana, such as Tabacum and Rustica, can be suitably used. There are no restrictions on the variety, and well-known varieties such as burley or flue-cured tobacco can be used. One or more of these leaf tobaccos can be mixed and used. A suitable blend of the above varieties can be used as the mixture to achieve the desired flavor.

When the tobacco composition before storage contains the reconstituted tobacco, the content of the reconstituted tobacco in 100% by weight of the tobacco composition before storage is preferably 5 to 85% by weight, and more preferably 10 to 30% by weight. Furthermore, when the tobacco composition before storage contains the second dried leaf tobacco, the content of the second dried leaf tobacco in 100% by weight of the tobacco composition before storage is preferably 5 to 85% by weight, and more preferably 10 to 50% by weight.

The tobacco composition before storage may further contain a non-tobacco flavoring material. A non-tobacco flavoring agent is a flavoring agent that is not derived from tobacco. Examples include flavors, cooling agents, and combinations thereof. Known flavors and cooling agents may be used.

In particular, the following fragrances can be used alone or in combination:
Acetanisole, acetophenone, acetylpyrazine, 2-acetylthiazole, alfalfa extract, amyl alcohol, amyl butyrate, trans-anethole, star anise oil, apple juice, balsam of Peru oil, beeswax absolute, benzaldehyde, benzoin resinoid, benzyl alcohol, benzyl benzoate, benzyl phenylacetate, benzyl propionate, 2,3-butanedione, 2-butanol, butyl butyrate, butyric acid, caramel, cardamom oil, carob absolute, β-carotene, carrot juice, L-carvone, β- Caryophyllene, cassia bark oil, cedarwood oil, celery seed oil, chamomile oil, cinnamaldehyde, cinnamic acid, cinnamyl alcohol, cinnamyl cinnamate, citronella oil, DL-citronellol, clary sage extract, cocoa, coffee, konjac oil, coriander oil, cuminaldehyde, davana oil, δ-decalactone, γ-decalactone, decanoic acid, dill herb oil, 3,4-dimethyl-1,2-cyclopentanedione, 4,5-dimethyl-3-hydroxy-2,5-dihydrofuran-2-one, 3,7-dimethyl-6-octenoic acid, 2,3 -dimethylpyrazine, 2,5-dimethylpyrazine, 2,6-dimethylpyrazine, ethyl 2-methylbutyrate, ethyl acetate, ethyl butyrate, ethyl hexanoate, ethyl isovalerate, ethyl lactate, ethyl laurate, ethyl levulinate, ethyl maltol, ethyl octanoate, ethyl oleate, ethyl palmitate, ethyl phenylacetate, ethyl propionate, ethyl stearate, ethyl valerate, ethyl vanillin, ethyl vanillin glucoside, 2-ethyl-3,(5 or 6)-dimethylpyrazine, 5-ethyl-3-hydroxy-4-methyl-2(5H)-furanone, 2 -Ethyl-3-methylpyrazine, eucalyptol, fenugreek absolute, gene absolute, gentian root infusion, geraniol, geranyl acetate, grape juice, guaiacol, guava extract, gamma-heptalactone, gamma-hexalactone, hexanoic acid, cis-3-hexen-1-ol, hexyl acetate, hexyl alcohol, phenylhexyl acetate, honey, 4-hydroxy-3-pentenoic acid lactone, 4-hydroxy-4-(3-hydroxy-1-butenyl)-3,5,5-trimethyl-2-cyclohexen-1-one, 4- (para-hydroxyphenyl)-2-butanone, sodium 4-hydroxyundecanoate, inmortell absolute, beta-ionone, isoamyl acetate, isoamyl butyrate, isoamyl phenylacetate, isobutyl acetate, isobutyl phenylacetate, jasmine absolute, cola nut tincture, labdanum oil, lemon terpeneless oil, licorice extract, linalool, linalyl acetate, lovage root oil, maltol, maple syrup, menthol, menthone, L-menthyl acetate, paramethoxybenzaldehyde, methyl-2-pyrrolyl ketone, an Methyltranilate, Methyl Phenylacetate, Methyl Salicylate, 4'-Methylacetophenone, Methylcyclopentenolone, 3-Methylvaleric Acid, Mimosa Absolute, Honey Honey, Myristic Acid, Nerol, Nerolidol, γ-Nonalactone, Nutmeg Oil, δ-Octalactone, Octanal, Octanoic Acid, Orange Flower Oil, Orange Oil, Orris Root Oil, Palmitic Acid, ω-Pentadecalactone, Peppermint Oil, Petitgrain Oil of Paraguay, Phenethyl Alcohol, Phenethyl Phenylacetate, Phenylacetic Acid, Piperonal, Plum Extract, Propenyl Glycol Aethol, propyl acetate, 3-propylidenephthalide, prune juice, pyruvic acid, raisin extract, rose oil, rum, sage oil, sandalwood oil, spearmint oil, styrax absolute, marigold oil, tea distillate, α-terpineol, terpinyl acetate, 5,6,7,8-tetrahydroquinoxaline, 1,5,5,9-tetramethyl-13-oxacyclo(8.3.0.0(4.9))tridecane, 2,3,5,6-tetramethylpyrazine, thyme oil, tomato extract, 2-tridecanone, triethyl citrate , 4-(2,6,6-trimethyl-1-cyclohexenyl)2-buten-4-one, 2,6,6-trimethyl-2-cyclohexene-1,4-dione, 4-(2,6,6-trimethyl-1,3-cyclohexadienyl)2-buten-4-one, 2,3,5-trimethylpyrazine, γ-undecalactone, γ-valerolactone, vanilla extract, vanillin, veratraldehyde, violet leaf absolute, N-ethyl-p-menthane-3-carboxamide (WS-3), ethyl-2-(p-menthane-3-carboxamide)acetate (WS-5).

Among these, menthol is preferred. Ordinary tobacco materials contain relatively large amounts of components (component L) with an RI of 1600 or less. As a result, with ordinary tobacco materials, component L interferes with the flavor, preventing the flavor's properties from being fully exhibited. However, the tobacco composition of this embodiment is able to fully exhibit the flavor's properties. Because menthol has an RI of 1600 or less, tobacco compositions containing menthol allow the flavor of menthol to be fully enjoyed.

The tobacco composition before storage can be produced by known methods. For example, it can be produced by mixing the individual components. Alternatively, the individual components can be mixed to form a composition, which can then be spread to prepare a sheet, and the sheet itself can be used as the composition.

(Condition (1))
Under condition (1), the tobacco composition before storage is stored at a moisture content of 10% by weight or less. That is, the tobacco composition before storage is stored while maintaining a moisture content of 10% by weight or less. Note that the moisture content of the tobacco composition during storage may vary as long as it is maintained at 10% by weight or less, but it is preferable that this moisture content be maintained. The moisture content of the tobacco composition before storage is preferably 7% by weight or less, and more preferably 6% by weight or less. The lower limit of the moisture content range of the tobacco composition before storage can be, for example, 3% by weight or more. The moisture content of the tobacco composition before storage can be adjusted and maintained, for example, by the following method. One example is a method in which the tobacco composition with a moisture content adjusted to 10% by weight is stored in a container or bag with gas barrier properties. The moisture content of the tobacco composition before storage can also be measured by the following method. The tobacco composition before storage is pulverized and an arbitrary amount in the range of 1 to 2 g is weighed into a heat-resistant dish. The pulverized tobacco composition is then dried in an oven set to 80°C for 3 hours. The change in weight before and after drying is converted into the amount of water, and the water content is calculated. Alternatively, the water content of the ground raw material may be measured by Karl Fischer moisture determination.

(Condition (2))
In condition (2), the tobacco composition before storage is stored in a light-shielding environment. That is, the tobacco composition before storage is stored while being kept in a state where it is not exposed to light. The light-shielding environment is not particularly limited as long as it is an environment where the tobacco composition before storage is not exposed to light, and examples thereof include packaging in a light-shielding aluminum zip-top bag.

(Condition (3))
Under condition (3), the tobacco composition before storage is stored at 40°C or below. That is, the tobacco composition before storage is stored while maintaining a temperature of 40°C or below. The temperature of the tobacco composition during storage may vary as long as it is maintained at 40°C or below, but it is preferable that this temperature be maintained. The temperature of the tobacco composition before storage is preferably 25°C or below, and more preferably 15°C or below. The lower limit of the temperature range of the tobacco composition before storage can be, for example, minus 78°C or above. Examples of methods for maintaining the temperature of the tobacco composition before storage at 40°C or below include storing it in a cool, dark place away from direct sunlight.

[Method for preserving tobacco composition]
The tobacco composition preservation method according to this embodiment includes a step of preserving a pre-preserved tobacco composition containing first dried leaf tobacco obtained by drying the tobacco composition so that it exhibits a green color for 50 days or more under one or more of the following conditions (1) to (3):
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below.

In the tobacco composition preservation method according to this embodiment, a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying to present a green color is stored for 50 days or more under one or more of the conditions (1) to (3) above, thereby suppressing discoloration of the first dried leaf tobacco, as described above. Therefore, during storage of a tobacco composition containing first dried leaf tobacco obtained by drying to present a green color, discoloration of the first dried leaf tobacco is suppressed, and the green color is sufficiently maintained. In other words, the quality of the tobacco composition is sufficiently maintained.

[Non-combustion heating smoking article]
The non-combustion heat-activated smoking article according to this embodiment includes the tobacco composition according to this embodiment. The tobacco composition according to this embodiment is suitable for non-combustion heat-activated smoking articles. FIG. 1 shows one embodiment of a non-combustion heat-activated smoking article. As shown in FIG. 1, the non-combustion heat-activated smoking article 20 includes a tobacco segment 20A, a cylindrical cooling section 20B having perforations on its circumference, and a filter section 20C. The non-combustion heat-activated smoking article 20 may include other components. The axial length of the non-combustion heat-activated smoking article 20 is not limited, but is preferably 40 to 90 mm, more preferably 50 to 75 mm, and even more preferably 50 to 60 mm or less. The circumferential length of the non-combustion heat-activated smoking article 20 is preferably 16 to 25 mm, more preferably 20 to 24 mm, and even more preferably 21 to 23 mm. For example, an embodiment may include a tobacco segment 20A having a length of 20 mm, a cooling section 20B having a length of 20 mm, and a filter section 20C having a length of 7 mm. The lengths of these individual components can be changed as appropriate depending on manufacturability, required quality, etc. Fig. 1 shows an embodiment in which the first segment 25 is disposed, but it is also possible to dispose the first segment 25 and to dispose only the second segment 26 downstream of the cooling section 20B.

(Tobacco segment 20A)
The tobacco filler 21 in the tobacco segment 20A contains the tobacco composition according to this embodiment. The method for filling the tobacco filler 21 into the wrapper 22 is not particularly limited, and for example, the tobacco filler 21 may be wrapped in the wrapper 22, or the tobacco filler 21 may be filled into a tubular wrapper 22. When the tobacco filler 21 has a longitudinal direction, such as a rectangular shape, it may be filled so that the longitudinal direction is in an unspecified direction within the wrapper 22, or may be aligned in the axial direction of the tobacco segment 20A or in a direction perpendicular to the axial direction. When the tobacco segment 20A is heated, the tobacco components, aerosol source, and water contained in the tobacco filler 21 vaporize and are available for inhalation.

(Cooling part 20B)
The cooling section 20B is preferably configured as a tubular member. The tubular member may be, for example, a cardboard tube 23 formed by processing cardboard into a cylindrical shape. Alternatively, the cooling section 20B may be formed from a thin sheet of material that is wrinkled and then pleated, gathered, or folded to form channels. Examples of such materials include sheet materials selected from the group consisting of polyethylene, polypropylene, polyvinyl chloride, polyethylene terephthalate, polylactic acid, cellulose acetate, and aluminum foil. The total surface area of the cooling section 20B is appropriately adjusted taking cooling efficiency into consideration, but may be, for example, 300 to 1000 ^{mm 2} /mm 2 . The cooling section 20B is preferably provided with perforations 24. The presence of the perforations 24 allows ambient air to be introduced into the cooling section 20B during inhalation. This allows the vaporized aerosol components generated by heating the tobacco segment 20A to come into contact with the ambient air, lowering their temperature and liquefying them to form an aerosol. The diameter (distance across) of the perforations 24 is not particularly limited, but may be, for example, 0.5 to 1.5 mm. The number of perforations 24 is not particularly limited, and may be one or two or more. For example, a plurality of perforations 24 may be provided on the circumference of the cooling portion 20B.

The cooling section 20B may be rod-shaped with an axial length of, for example, 7 to 28 mm. For example, the axial length of the cooling section 20B may be 18 mm. The axial cross-sectional shape of the cooling section 20B may be substantially circular, with a diameter of 5 to 10 mm. For example, the diameter of the cooling section 20B may be approximately 7 mm.

(Filter part 20C)
The configuration of the filter portion 20C is not particularly limited, and may be composed of one or more packed layers. The outside of the packed layer may be wrapped with one or more sheets of wrapping paper. The airflow resistance of the filter portion 20C can be appropriately changed depending on the amount and material of the filter filler filled in the filter portion 20C. For example, when the filter filler is cellulose acetate fiber, increasing the amount of cellulose acetate fiber filled in the filter portion 20C can increase the airflow resistance. When the filter filler is cellulose acetate fiber, the packing density of the cellulose acetate fiber may be 0.13 to 0.18 g/ ^cm3 . The airflow resistance is a value measured using an airflow resistance measuring device (product name: SODIMAX, manufactured by SODIM).

The circumferential length of the filter portion 20C is not particularly limited, but is preferably 16 to 25 mm, more preferably 20 to 24 mm, and even more preferably 21 to 23 mm. The axial length of the filter portion 20C (the horizontal direction in FIG. 1) can be selected from 4 to 10 mm, and is selected so that the airflow resistance is 15 to 60 mmH ₂ O/seg. The axial length of the filter portion 20C is preferably 5 to 9 mm, more preferably 6 to 8 mm. The cross-sectional shape of the filter portion 20C is not particularly limited, but can be, for example, circular, elliptical, polygonal, etc. In addition, a frangible capsule containing a fragrance, fragrance beads, or fragrance may be directly added to the filter portion 20C.

The filter section 20C may have a center hole section as the first segment 25. The center hole section is composed of a first filling layer 25a with one or more hollow sections and an inner plug wrapper (inner wrapping paper) 25b that covers the filling layer. The center hole section functions to increase the strength of the mouthpiece section. The center hole section may not have an inner plug wrapper 25b and its shape may be maintained by thermoforming. The first filling layer 25a may be, for example, a rod with an inner diameter of 5.0 to 1.0 mm, densely packed with cellulose acetate fibers and hardened with 6 to 20 weight percent of a plasticizer containing triacetin added to the cellulose acetate. Because the first filling layer 25a has a high fiber packing density, during inhalation, air and aerosol flow only through the hollow sections and barely any flow within the first filling layer 25a. Because the first filling layer 25a inside the center hole section is a fiber-filled layer, the feel from the outside during use is less likely to cause discomfort to the user. The filter section 20C may include a second segment 26. The second segment 26 is composed of a second packed layer 26a and an inner plug wrapper (inner wrapping paper) 26b that covers the packed layer.

The first filling layer 25a and the second filling layer 26a are connected by an outer plug wrapper (outer wrapping paper) 27. The outer plug wrapper 27 can be, for example, a cylindrical piece of paper. The tobacco segment 20A, the cooling section 20B, and the connected first filling layer 25a and second filling layer 26a are connected by a mouthpiece lining paper 28. These connections can be made, for example, by applying glue such as vinyl acetate glue to the inner surface of the mouthpiece lining paper 28 and wrapping the three components around it. These components may also be connected in multiple layers using multiple lining papers.

The combination of a non-combustion heated smoking article and a heating device for generating aerosol is also referred to as a non-combustion heated smoking system. An example of such a system is shown in Figure 2. In Figure 2, the non-combustion heated smoking system comprises a non-combustion heated smoking article 20 and a heating device 10 that heats a tobacco segment 20A from the outside.

The heating device 10 comprises a body 11, a heater 12, a metal tube 13, a battery unit 14, and a control unit 15. The body 11 has a cylindrical recess 16, and the heater 12 and metal tube 13 are positioned corresponding to the tobacco segment 20A to be inserted therein. The heater 12 may be an electrical resistance heater, and is heated by power supplied from the battery unit 14 in response to instructions from the control unit 15, which controls the temperature. The heat generated by the heater 12 is transferred to the tobacco segment 20A through the metal tube 13, which has high thermal conductivity. While Figure 2 shows a configuration in which the heating device 10 heats the tobacco segment 20A from the outside, it may also heat from the inside. The heating temperature of the heating device 10 is not particularly limited, but is preferably 400°C or less, more preferably 150 to 400°C, and even more preferably 200 to 350°C. The heating temperature refers to the temperature of the heater in the heating device 10. It is also possible to place a susceptor inside the tobacco segment 20A and heat the tobacco segment 20A using the induction method.

The present embodiment will be explained in more detail below using examples, but the present embodiment is not limited to these examples.

[Example 1]
(Production of pre-storage tobacco composition)
A first cured leaf tobacco was produced by drying to a green color, with an a ^* value of -11.9 measured according to the L ^* a ^* b ^* method standardized in CIE 1976 and a moisture content of 4.2% by weight. Specifically, harvested burley leaf tobacco was irradiated with microwaves at an output of 1000 W and dried. The moisture content after drying was 4.2% by weight. The first cured leaf tobacco was used as a tobacco composition before storage.

(Storage and discoloration evaluation of tobacco compositions before storage)
The tobacco composition before storage was placed in a vial, sealed, and stored for 24 hours at 40°C in a light-shielded environment so that the moisture content was maintained at 4% by weight. The a ^* value after storage was measured, and the amount of change in the a ^* value before and after storage was defined as the initial slope Δa ^* and calculated. The results are shown in Figure 4.

[Example 2]
The first dried leaf tobacco was conditioned for 24 hours in an atmosphere of 22°C and 60% relative humidity, and a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 1, except that the moisture content was changed to 11% by weight. The results are shown in Figure 4.

[Example 3]
The first dried leaf tobacco was conditioned for 24 hours in an atmosphere of 22°C and 78% relative humidity, and the moisture content was changed to 17% by weight, and an unpreserved tobacco composition was produced, preserved, and evaluated in the same manner as in Example 1. The results are shown in Figure 4.

[Example 4]
The first dried leaf tobacco was conditioned for 24 hours in an atmosphere of 22°C and 86% relative humidity, and the moisture content was changed to 21% by weight, and other than this, a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 1. The results are shown in Figure 4.

[Example 5]
Except for conditioning the first dried leaf tobacco in an atmosphere of 22°C and 93% relative humidity for 24 hours and changing the moisture content to 27% by weight, a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 1. The results are shown in Figure 4.

As shown in Figure 4, when stored in the same 40°C environment, the lower the moisture content, the more discoloration was suppressed, and discoloration was particularly suppressed when the moisture content was 10% by weight or less.

[Example 6]
(Production of pre-storage tobacco composition)
Harvested Burley leaf tobacco was conditioned for 12 hours in an environment at a temperature of 35°C and a relative humidity of 64%. Subsequently, the moisture content of the mesophyll was conditioned in an environment at a temperature of 45°C and a relative humidity of 32% until the moisture content of the mesophyll was below 25% by weight. Thereafter, the mesophyll was dried in an environment at 68°C/20% RH until the moisture content of the vein portion was below 12% by weight. After drying, the mesophyll was conditioned for 48 hours in an environment at 22°C/60% RH. The mesophyll and vein portions were then separated, and the color of the mesophyll was measured, resulting in an a ^* value of -8.2. The mesophyll portion was conditioned to a moisture content of 4.1% by weight and dried to a green color, thereby producing a first cured leaf tobacco. This first cured leaf tobacco was used as a tobacco composition before storage.

(Storage and discoloration evaluation of tobacco compositions before storage)
The tobacco composition before storage was placed in a vial and stored at 30°C under a light-shielded environment for 120 hours so that the moisture content was maintained at 4.1% by weight. The a ^* value was measured periodically during storage to confirm changes in the a ^* value. The results are shown in Figure 5.

[Example 7]
Except for conditioning the first dried leaf tobacco in an atmosphere of 25°C and 85% relative humidity for 15 minutes to change the moisture content to 5.3% by weight, a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 6. The results are shown in Figure 5.

[Example 8]
Except for conditioning the first dried leaf tobacco in an atmosphere of 25°C and 85% relative humidity for 25 minutes to change the moisture content to 6.3% by weight, a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 6. The results are shown in Figure 5.

[Example 9]
Except for conditioning the first dried leaf tobacco in an atmosphere of 25°C and 85% relative humidity for 30 minutes to change the moisture content to 6.7% by weight, a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 6. The results are shown in Figure 5.

[Example 10]
The first dried leaf tobacco was conditioned for 24 hours in an atmosphere of 22°C and 55% relative humidity, and the moisture content was changed to 7.6% by weight, and an unpreserved tobacco composition was produced, preserved, and evaluated in the same manner as in Example 6. The results are shown in Figure 5.

[Example 11]
Except for conditioning the first dried leaf tobacco in an atmosphere of 25°C and 85% relative humidity for 40 minutes to change the moisture content to 8.3% by weight, a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 6. The results are shown in Figure 5.

[Example 12]
The first dried leaf tobacco was conditioned for 48 hours in an atmosphere of 22°C and 55% relative humidity, and a pre-storage tobacco composition was produced, stored, and evaluated in the same manner as in Example 6, except that the moisture content was changed to 9.0% by weight. The results are shown in Figure 5.

[Example 13]
Except for changing the moisture content of the first dried leaf tobacco to 10.1% by weight by conditioning it for 6 hours in an atmosphere of 22°C and 60% relative humidity, a tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 6. The results are shown in Figure 5.

As shown in Figure 5, it was found that discoloration was more suppressed as the moisture content decreased when stored in the same 30°C environment. In particular, when the moisture content was 7% by weight or less, the a ^* value was -4.0 or less even after 120 days of storage, indicating that discoloration was significantly suppressed.

[Example 14]
(Production of pre-storage tobacco composition)
A first cured leaf tobacco was produced by drying to a green color, with an a ^* value of -4.4 measured according to the L ^* a ^* b ^* method standardized in CIE 1976 and a moisture content of 7% by weight or less. Specifically, harvested burley leaf tobacco was irradiated with microwaves at an output of 1000 W and dried. The first cured leaf tobacco was used as a tobacco composition before storage.

(Storage and discoloration evaluation of tobacco compositions before storage)
The tobacco composition before storage was thinly spread in a transparent polypropylene bag, sealed, and stored under a luminous emittance of 400 lx at 22°C. The a ^* value was measured periodically during storage, and the change in the a ^* value (Δa ^* ) was calculated. The results are shown in Figure 6.

[Example 15]
Except for storing the tobacco composition in a light-shielded state, the tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 14. The results are shown in Figure 6.

As shown in Figure 6, when stored in the same 22°C environment, Example 15, which was stored in a light-shielded state, showed a smaller change in the a ^* value (Δa ^* ) than Example 14, which was stored in a non-light-shielded state.

[Example 16]
(Production of pre-storage tobacco composition)
A first cured leaf tobacco was produced by drying to a green color, with an a ^* value of -4.4 measured according to the L ^* a ^* b ^* method standardized in CIE 1976 and a moisture content of 7% by weight or less. Specifically, harvested burley leaf tobacco was irradiated with microwaves at an output of 1000 W and dried. The first cured leaf tobacco was used as a tobacco composition before storage.

(Storage and discoloration evaluation of tobacco compositions before storage)
The tobacco composition before storage was placed in a transparent polypropylene bag, sealed, and stored at 7° C. The a ^* value was measured periodically during storage, and the amount of change in the a ^* value (Δa ^* ) was calculated. The results are shown in FIG.

[Example 17]
Except for being stored in an environment of 22° C., the tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 16. The results are shown in FIG.

[Example 18]
Except for being stored in an environment of 30° C., the tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 16. The results are shown in FIG.

[Example 19]
Except for being stored in an environment of 40° C., the tobacco composition before storage was produced, stored, and evaluated in the same manner as in Example 16. The results are shown in FIG.

As shown in FIG. 7, it was found that the lower the storage temperature, the smaller the amount of change in the a ^* value (Δa ^* ).

[Example 20]
(Production of pre-storage tobacco composition)
A first cured leaf tobacco was produced by drying to a green color, with an a ^* value of -10 measured according to the L ^* a ^* b ^* method standardized in CIE 1976 and a moisture content of 3% by weight. Specifically, the harvested leaf tobacco was immersed in a boiling water bath for 90 seconds, removed, and then quickly cooled in cold water. After cooling, moisture was thoroughly removed in a reduced pressure environment of 10 Pa. After moisture removal, the leaf tobacco was pulverized to produce a first cured leaf tobacco. 30% by weight of low-moisture-content grade glycerin was added to the first cured leaf tobacco, and this was used as a tobacco composition before storage.

(Storage and discoloration evaluation of tobacco compositions before storage)
The tobacco composition before storage was placed in a vial and stored at 40°C under light-shielded conditions. The a ^* value was measured periodically during storage to confirm changes in the a ^* value. The results are shown in Figure 8.

[Example 21]
To the first dried leaf tobacco, 30% by weight of low-moisture-content 1,2-propanediol was added instead of glycerin to prepare a pre-storage tobacco composition. Except for this, the pre-storage tobacco composition was produced, stored, and evaluated in the same manner as in Example 20. The results are shown in Figure 8.

[Example 22]
To the first dried leaf tobacco, 30% by weight of water was added instead of glycerin to prepare a pre-storage tobacco composition. Except for this, a pre-storage tobacco composition was produced, stored, and evaluated in the same manner as in Example 20. The results are shown in Figure 8.

As shown in FIG. 8, it was found that the amount of change in the a ^* value was reduced by adding glycerin or 1,2-propanediol.

The present invention preferably includes the following embodiments:

[1] A tobacco composition obtained by storing a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying to present a green color under one or more of the following conditions (1) to (3) for 50 days or more.
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below.

[2] The tobacco composition according to [1], wherein the first dried leaf tobacco has an a ^* value of -2 or less as measured according to the L ^* a ^* b ^* method standardized in CIE 1976.

[3] The tobacco composition described in [1] or [2], wherein the drying step comprises placing the harvested fresh leaves in an environment of 45°C or less until the moisture content of the mesophyll is 25% by weight or less.

[4] The drying is performed by placing the harvested fresh leaves in an environment of 30 to 40 ° C and a relative humidity of 60 to 70% for 6 to 12 hours, and then
The tobacco composition according to any one of [1] to [3], further comprising a step of placing the tobacco composition in an environment of 45°C or less until the moisture content of the mesophyll portion is reduced to 25% by weight or less.

[5] The tobacco composition according to any one of [1] to [4], wherein the first dried leaf tobacco is produced by extracting only the mesophyll portion when the moisture content of the mesophyll portion during the drying process reaches 12% by weight or less.

[6] The tobacco composition according to any one of [1] to [5], wherein the condition (1) is a condition in which the tobacco composition before storage is stored at a moisture content of 7% by weight or less.

[7] The tobacco composition described in any one of [1] to [6], wherein the tobacco composition before storage further contains at least one selected from the group consisting of glycerin, 1,2-propylene glycol, and 1,3-propylene glycol.

[8] The tobacco composition described in [7], wherein the tobacco composition before storage further contains glycerin.

[9] The tobacco composition according to [7] or [8], wherein the content of at least one substance selected from the group consisting of glycerin, 1,2-propylene glycol, and 1,3-propylene glycol contained in 100% by weight of the tobacco composition before storage is 5 to 30% by weight.

[10] The tobacco composition according to any one of [1] to [9], wherein the content of the first dried leaf tobacco contained in 100% by weight of the tobacco composition before storage is 30 to 95% by weight.

[11] The tobacco composition described in any one of [1] to [10], wherein the tobacco composition before storage further contains an aerosol source other than glycerin, 1,2-propylene glycol, and 1,3-propylene glycol.

[12] The tobacco composition described in any one of [1] to [11], wherein the pre-storage tobacco composition further contains reconstituted tobacco.

[13] The tobacco composition according to [12], wherein the content of the reconstituted tobacco in 100% by weight of the tobacco composition before storage is 5 to 85% by weight.

[14] The tobacco composition described in any one of [1] to [13], wherein the tobacco composition before storage further contains a second dried leaf tobacco other than the first dried leaf tobacco.

[15] The tobacco composition according to [14], wherein the content of the second dried leaf tobacco contained in 100% by weight of the tobacco composition before storage is 5 to 85% by weight.

[16] The tobacco composition described in any one of [1] to [15], wherein the tobacco composition before storage further contains a non-tobacco flavoring material.

[17] The tobacco composition described in [16], wherein the non-tobacco flavoring material is selected from the group consisting of flavorings, cooling agents, and combinations thereof.

[18] The tobacco composition described in [17], wherein the flavoring is menthol.

[19] A non-combustion heating smoking article comprising the tobacco composition described in any one of [1] to [18].

[20] A method for preserving a tobacco composition, comprising a step of preserving a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying so as to present a green color, for 50 days or more under one or more of the following conditions (1) to (3):
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below.

REFERENCE SIGNS LIST 10 Heating device 11 Body 12 Heater 13 Metal tube 14 Battery unit 15 Control unit 16 Recess 17 Ventilation hole 20 Non-combustion heating smoking article 20A Tobacco segment 20B Cooling section 20C Filter section 21 Tobacco filler 22 Cigarette paper 23 Paper tube 24 Perforations 25 First segment 25a First filling layer 25b Inner plug wrapper 26 Second segment 26a Second filling layer 26b Inner plug wrapper 27 Outer plug wrapper 28 Lining paper

Claims (20)

A tobacco composition obtained by storing a pre-storage tobacco composition containing first dried leaf tobacco obtained by drying to present a green color under one or more of the following conditions (1) to (3) for 50 days or more.
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below. 2. The tobacco composition of claim 1, wherein the first dried leaf tobacco has an a ^* value of −2 or less as measured according to the L ^* a ^* b ^* method standardized in CIE 1976. The tobacco composition described in claim 1 or 2, wherein the drying step comprises placing the harvested fresh leaves in an environment of 45°C or less until the moisture content of the mesophyll is 25% by weight or less. The drying is carried out by leaving the harvested fresh leaves in an environment of 30 to 40°C and a relative humidity of 60 to 70% for 6 to 12 hours, and then
The tobacco composition according to any one of claims 1 to 3, further comprising a step of placing the tobacco composition in an environment of 45°C or less until the moisture content of the mesophyll portion is reduced to 25% by weight or less. The tobacco composition according to any one of claims 1 to 4, wherein the first dried leaf tobacco is produced by extracting only the mesophyll portion during the drying process when the moisture content of the mesophyll portion reaches 12% by weight or less. The tobacco composition according to any one of claims 1 to 5, wherein the condition (1) is a condition in which the tobacco composition before storage is stored at a moisture content of 7% by weight or less. The tobacco composition according to any one of claims 1 to 6, wherein the tobacco composition before storage further contains at least one selected from the group consisting of glycerin, 1,2-propylene glycol, and 1,3-propylene glycol. The tobacco composition of claim 7, wherein the tobacco composition before storage further contains glycerin. The tobacco composition according to claim 7 or 8, wherein the content of at least one element selected from the group consisting of glycerin, 1,2-propylene glycol, and 1,3-propylene glycol in 100% by weight of the tobacco composition before storage is 5 to 30% by weight. The tobacco composition according to any one of claims 1 to 9, wherein the content of the first dried leaf tobacco contained in 100% by weight of the tobacco composition before storage is 30 to 95% by weight. The tobacco composition according to any one of claims 1 to 10, wherein the tobacco composition before storage further comprises an aerosol source other than glycerin, 1,2-propylene glycol, and 1,3-propylene glycol. The tobacco composition according to any one of claims 1 to 11, wherein the pre-storage tobacco composition further contains reconstituted tobacco. The tobacco composition according to claim 12, wherein the content of the reconstituted tobacco in 100% by weight of the tobacco composition before storage is 5 to 85% by weight. The tobacco composition according to any one of claims 1 to 13, wherein the pre-storage tobacco composition further comprises a second dried leaf tobacco other than the first dried leaf tobacco. The tobacco composition of claim 14, wherein the content of the second dried leaf tobacco in 100% by weight of the tobacco composition before storage is 5 to 85% by weight. The tobacco composition according to any one of claims 1 to 15, wherein the tobacco composition before storage further contains a non-tobacco flavoring material. The tobacco composition of claim 16, wherein the non-tobacco flavoring material is selected from the group consisting of flavorings, cooling agents, and combinations thereof. The tobacco composition of claim 17, wherein the flavoring is menthol. A non-combustion heating smoking article comprising the tobacco composition described in any one of claims 1 to 18. A method for preserving a tobacco composition, comprising a step of preserving a pre-storage tobacco composition containing first cured leaf tobacco obtained by drying to present a green color, for 50 days or more under one or more of the following conditions (1) to (3):
(1) The tobacco composition before storage is stored at a moisture content of 10% by weight or less.
(2) The tobacco composition before storage is stored in a light-shielding environment.
(3) The tobacco composition before storage is stored at 40°C or below.