Method for preparing a tobacco extract, tobacco extract prepared thereby and use thereof

Abstract

A method, more specifically a method of extracting one or more relevant volatile compounds from a tobacco material, the method comprising the steps of: i) providing a tobacco material; ii) subjecting the tobacco material to steam distillation; and iii) extracting one or more relevant volatile compounds from the tobacco material with a solvent; wherein the distillation step (ii) and the extraction step (iii) are performed simultaneously and at a pH of no more than 2, and wherein both the distillation step (ii) and the extraction step (iii) are performed for a time of about 8 to about 20 hours.

Description

[0001] This application is a divisional application of the invention application with application number "201880028038.6" and invention title "Method". Technical Field

[0002] This invention relates to a method for extracting one or more related volatile compounds from tobacco materials, a tobacco extract that can be obtained or acquired by said method, a tobacco product containing said tobacco extract, a method for preparing said tobacco product, and the use of said tobacco extract. Background Technology

[0003] Common smoking products, such as cigarettes, have a generally cylindrical rod-like structure and consist of a column of smokeable material, such as tobacco (e.g., in the form of shredded tobacco), surrounded by wrapping paper, thus forming what is known as a "cigarette stick." Typically, cigarettes have a cylindrical filter element aligned end-to-end with the cigarette stick, and this filter element is attached to one end of the cigarette stick using an outer wrapping material called a tipping paper. The smoker uses the cigarette by lighting one end of it and burning the stick. The smoker then receives the mainstream smoke into his / her mouth by inhaling from the opposite end of the cigarette (e.g., the filter end).

[0004] They also designed new smoking products and launched them on the market as a new generation of products. These can be divided into three main categories and can be called "vaping articles": 1. Electronic devices; 2. Heating device; and 3. Dual-purpose device.

[0005] A dual-purpose device is a combination of an electronic device and a heating device.

[0006] Over the years, various processing methods and additives have been proposed to alter the overall characteristics or properties of tobacco materials used in tobacco products. For example, additives or processing techniques have been used to change the chemical or sensory properties of tobacco materials in cigarettes, or, in the case of tobacco materials for smoking or e-cigarette use, to change the chemical or sensory properties of the mainstream smoke / aerosol produced by smoking / e-cigarette products containing such tobacco materials.

[0007] Sensory properties can be achieved, for example, by incorporating flavoring materials into various components of cigarettes or smoking / e-cigarette products. Exemplary flavoring additives include menthol and Maillard reaction products such as pyrazines, amino sugars, and Amadori compounds.

[0008] However, there remains a need in the art for compositions suitable for addition to tobacco products (which may include smoking and / or e-cigarette products) to introduce desired sensory properties. In particular, it is desirable to provide methods for the efficient extraction and separation of such compositions. Summary of the Invention

[0009] According to some embodiments described herein, a method for extracting one or more related volatile compounds from tobacco materials is provided, the method comprising the following steps: i) Providing tobacco materials; ii) subjecting the tobacco material to steam distillation; and iii) Extract one or more related volatile compounds from the tobacco material using a solvent; The distillation step (ii) and the extraction step (iii) are carried out simultaneously at a pH not greater than 2, and the distillation step (ii) and the extraction step (iii) are carried out for a time of about 8 to about 20 hours.

[0010] According to some embodiments described herein, a tobacco extract that is obtainable or acquireable by the methods defined herein is provided, wherein the tobacco extract contains one or more related volatile compounds in an amount of at least about 75% by weight of the tobacco extract.

[0011] According to some of the embodiments described herein, a tobacco product is provided that comprises a tobacco extract as defined herein.

[0012] According to some embodiments described herein, a method for preparing a tobacco product as defined herein is provided, the method comprising the following steps: (a) Preparation of tobacco extract according to the methods defined herein; and (b) Combining the tobacco extract directly with a tobacco product and / or combining the tobacco extract with reconstituted tobacco and optionally combining the reconstituted tobacco with a tobacco product.

[0013] Based on some of the embodiments described herein, uses of tobacco extracts as defined herein for improving the sensory properties of tobacco products are provided.

[0014] The present invention discloses the following embodiments: Option 1. A method for extracting one or more related volatile compounds from tobacco materials, the method comprising the following steps: i) Providing tobacco materials; ii) subjecting the tobacco material to steam distillation; and iii) Extract one or more related volatile compounds from the tobacco material using a solvent; The distillation step (ii) and the extraction step (iii) are carried out simultaneously at a pH not greater than 2, and the distillation step (ii) and the extraction step (iii) are carried out for a time of about 8 to about 20 hours.

[0015] Option 2. According to the method of Option 1, wherein the distillation step (ii) and the extraction step (iii) are carried out at a pH of not more than 2 for a total time period.

[0016] Option 3. The method according to Option 1 or 2, wherein the solvent is a nonpolar solvent.

[0017] Option 4. The method according to any one of Options 1 to 3, wherein the solvent is immiscible with water.

[0018] Option 5. The method according to any one of Options 1 to 4, wherein the solvent is selected from n-butanol, cyclohexane, dichloromethane, ethyl acetate, heptane, hexane, methyl tert-butyl ether, 2-butanone, pentane, diisopropyl ether, diethyl ether, and mixtures of pentane and diethyl ether.

[0019] Option 6. The method according to any one of Options 1 to 5, wherein the solvent is a mixture of pentane and diethyl ether.

[0020] Option 7. The method according to Option 6, wherein the solvent comprises pentane and diethyl ether in a weight ratio of 3:1 to 1:1, such as about 2:1 pentane to diethyl ether.

[0021] Scheme 8. The method according to any one of Schemes 1 to 7, wherein the distillation step (ii) and the extraction step (iii) are carried out at a pH of 0.5 to 2.

[0022] Scheme 9. The method according to any one of Schemes 1 to 8, wherein the distillation step (ii) and the extraction step (iii) are carried out at a pH of approximately 1.6.

[0023] Option 10. The method according to any one of Options 1 to 9, wherein both the distillation step (ii) and the extraction step (iii) are performed for approximately 8 to approximately 10 hours.

[0024] Option 11. The method according to any one of Options 1 to 10, wherein both the distillation step (ii) and the extraction step (iii) are performed for approximately 9 hours.

[0025] Option 12. The method according to any one of Options 1 to 11, wherein the distillation step (ii) and the extraction step (iii) are carried out at a temperature of up to about 130°C.

[0026] Option 13. The method according to any one of Options 1 to 12, wherein the tobacco material does not undergo any heat treatment between the distillation step (ii) and the extraction step (iii).

[0027] Scheme 14. The method according to any one of Schemes 1 to 13, wherein the one or more associated volatile compounds are selected from: sugars, sugar esters, amino acids, β-carotene, violetin, lutein, neoxanthin, phytol, lysine, sipranones, polyphenols, lignin, and mixtures thereof.

[0028] Option 15. The method according to any one of Options 1 to 13, wherein one or more related volatile compounds are selected from: methylbutanol, benzyl alcohol, phenethyl alcohol, methoxyvinylphenol, vinylphenol, hydroxydihydrodamascone, furfural, hydroxymethylfurfural, furanone, methylcyclopentenolone, dimethylpyrazine, trimethylpyrazine, tetramethylpyrazine, hydroxymethyl(methyl)pyrazine, isophorone, oxyisophorone, saffron aldehyde, ionone, damascone, β-damascone, megastigmatrienone, β- Dihydrodamascone, β-ionone, 2,6-nonadienal, 2-nonenal, linalool, linalool oxide, geranylacetone, farnesylacetone, methylheptadenone, solanone, solanine, norbornene lactone, ambroxol, sage lactone, isobutyric acid, isovaleric acid, 3-methylvaleric acid, heptanoic acid, benzoic acid, phenylacetic acid, o-cresol, p-cresol, methylthiopropional, guaiacol, vinylphenol, ethyl guaiacol, vinyl guaiacol, eugenol, vanillin and mixtures thereof.

[0029] Option 16. The method according to any one of Options 1 to 15, wherein the method further includes a purification step, which includes replacing the solvent used for extraction with another solvent suitable for tobacco products, such as ethanol.

[0030] Option 17. A tobacco extract that is obtainable or acquired by the method defined in any one of Options 1 to 16, wherein the tobacco extract contains one or more related volatile compounds in an amount of at least about 75% by weight of the tobacco extract.

[0031] Option 18. The tobacco extract according to Option 17, wherein the tobacco extract contains one or more related volatile compounds in an amount of at least about 90% by weight of the tobacco extract.

[0032] Option 19. The tobacco extract according to Option 17 or 18, wherein the tobacco extract contains one or more related volatile compounds in an amount of at least about 95% by weight of the tobacco extract.

[0033] Scheme 20. Tobacco products comprising tobacco extracts as defined in any one of Schemes 17 to 19.

[0034] Option 21. The tobacco product according to Option 20, wherein the tobacco extract is contained in the tobacco product in the form of a flavoring agent, a liquid, or a combination thereof, or in the form of reconstituted tobacco containing the tobacco extract.

[0035] Option 22. The tobacco product according to any one of Option 20 or 21, wherein the tobacco product is a smoking article or a smokeless tobacco product, an electronic cigarette, a heating device or a dual-use version of both, a cigarette, a cigar or a smokeless oral tobacco product.

[0036] Scheme 23. A method for preparing a tobacco product as defined in any one of Schemes 20 to 22, comprising the following steps: (a) Prepare tobacco extract according to any one of schemes 1 to 16; and (b) Combining the tobacco extract directly with a tobacco product and / or combining the tobacco extract with reconstituted tobacco and optionally combining the reconstituted tobacco with a tobacco product.

[0037] Scheme 24. Use of tobacco extracts as defined in any one of Schemes 17 to 19 for improving the sensory properties of tobacco products. Attached Figure Description

[0038] Embodiments of the invention have been described by way of example only, with reference to the accompanying drawings, in which: Figure 1 The Likens-Nickerson apparatus for simultaneous distillation and extraction is shown.

[0039] Figure 2 The simultaneous distillation-extraction apparatus is shown, which is effective when the solvent density is greater than that of water.

[0040] Figure 3 The simultaneous distillation-extraction apparatus used in Example 1 is shown, which is effective when the solvent density is low compared to water.

[0041] Figure 4 The simultaneous distillation-extraction apparatus used in Example 2 is shown, which is effective when the solvent density is low compared to water.

[0042] Figure 5 Showing Figure 3 Simultaneously, the distillation-extraction equipment has been expanded to extract compounds from a 2240-gram tobacco sample.

[0043] Figure 6 This is a reference chromatogram showing an exemplary chromatogram in which peaks are divided into three categories: volatile fragrances, semi-volatile fragrances, and diterpenes. This chromatogram is included only for ease of interpretation.

[0044] Figure 7Chromatograms obtained using a simultaneous distillation-extraction method at (a) pH 2.0 (according to the invention) and (b) pH 6.0 (outside the scope of the invention) are shown.

[0045] Figure 8 The chromatogram obtained using a simultaneous distillation-extraction method at pH 6.0 (outside the scope of this invention) is shown.

[0046] Figure 9 The chromatogram obtained using a simultaneous distillation-extraction method at pH 4.0 (outside the scope of this invention) is shown.

[0047] Figure 10 The chromatogram obtained using a simultaneous distillation-extraction method at pH 3.0 (outside the scope of this invention) is shown.

[0048] Figure 11 The chromatogram obtained at pH 2.0 (according to the present invention) using a simultaneous distillation-extraction method is shown.

[0049] Figure 12 The chromatogram obtained at pH 0.5 (according to the present invention) using a simultaneous distillation-extraction method is shown. Detailed Implementation

[0050] method A first aspect of the present invention provides a method for extracting one or more related volatile compounds from tobacco material, the method comprising the following steps: i) Providing tobacco materials; ii) subjecting the tobacco material to steam distillation; and iii) Extract one or more related volatile compounds from the tobacco material using a solvent; The distillation step (ii) and the extraction step (iii) are carried out simultaneously at a pH not greater than 2, and the distillation step (ii) and the extraction step (iii) are carried out for a time of about 8 to about 20 hours.

[0051] The term "tobacco material" as used in this article refers to material derived from species of the genus *Nicotiana*. The selection of *Nicotiana* species is unrestricted, and the types of one or more tobacco species used can be varied.

[0052] In some embodiments, the tobacco material is selected from flue-cured or Virginia type, Burley, sun-cured, Maryland type, dark tobacco, dark flue-cured tobacco, dark air-cured tobacco, light air-cured tobacco, Indian air-cured tobacco, Red Russian and Yellow tobacco, and mixtures thereof, as well as various other types of rare or specialty tobaccos (raw or processed tobacco). Tobacco material obtained through any other type of tobacco treatment that can alter the taste of tobacco (such as fermented tobacco or genetic modification or hybridization techniques) is also within the scope of this invention. For example, it is envisioned that tobacco plants can be genetically engineered or hybridized to increase or decrease the production of components, characteristics, or properties.

[0053] In some embodiments, the tobacco material is sun-cured tobacco, selected from Indian Kurnool and Oriental tobaccos, including Katerini, Prelip, Komotini, Xanthi, and Yambol. In some embodiments, the tobacco material is dark-colored air-cured tobacco, selected from Passanda, Cubano, Jatin, and Bezuki tobaccos. In some embodiments, the tobacco material is light-colored air-cured tobacco, selected from North Wisconsin and Galpao tobaccos.

[0054] In some implementations, the tobacco material is a blended or unblended mixture of flue-cured tobacco, burley tobacco, and oriental tobacco.

[0055] To prepare tobacco products for smoking / e-cigarette use or smokeless tobacco, tobacco species can be subjected to conditioning processes. Other types of conditioning processes, such as open-flame conditioning or sun-drying, can be applied to specific types of tobacco. It is preferred, but not mandatory, to age the harvested tobacco after conditioning.

[0056] Tobacco can be harvested at different stages of its growth, such as when the plant is about to sprout, grow leaves, or even when it begins to flower.

[0057] In some embodiments, at least a portion of a tobacco species (e.g., at least a portion of tobacco material) is used in an immature form. That is, in some embodiments, the plant, or at least a portion of the plant, is harvested before reaching a stage that is generally considered ripe or mature.

[0058] In some implementations, at least a portion of the tobacco species (e.g., at least a portion of the tobacco material) is used in a mature form. That is, in some implementations, the plant, or at least a portion of the plant, is harvested when it reaches a point traditionally considered ripe, overripe, or mature, which can be achieved using tobacco harvesting techniques conventionally employed by farmers. Both Oriental and Burley tobacco plants can be harvested. Additionally, Virginia tobacco leaves can be harvested by part of the plant or by leaf picking.

[0059] Tobacco species can be selected based on the abundance of various compounds present in the plant. For example, plants can be selected based on those that produce relatively large amounts of one or more desired isolated compounds (i.e., associated volatile compounds). In certain embodiments, tobacco species are specifically cultured for the abundance of compounds on their leaf surfaces. Tobacco plants can be grown in greenhouses, growing rooms, or in outdoor fields, or hydroponically.

[0060] Various parts or portions of a tobacco species can be used in the methods defined herein. In some embodiments, the whole plant, or substantially the whole plant, is harvested and used as is. The term "substantially the whole plant" as used herein means harvesting at least 90%, such as at least 95%, such as at least 99%. Alternatively, in some embodiments, various parts or segments of the plant are harvested or separated for further use after harvesting. In some embodiments, the tobacco material is selected from the leaves, stems, stems, and various combinations of these parts of the plant. The tobacco material of the present invention may thus comprise a whole plant or any part of a tobacco species.

[0061] In some embodiments, the tobacco material comprises tobacco leaves. In some embodiments, the tobacco material comprises whole tobacco leaves or shredded tobacco leaves. In some embodiments, the tobacco material comprises whole tobacco leaves. In some embodiments, the tobacco leaves comprise shredded tobacco leaves. In some embodiments, the tobacco material is ground tobacco.

[0062] In some embodiments, the tobacco material is stored at a temperature below 0°C prior to distillation and extraction. Therefore, in some embodiments, the tobacco material is kept frozen prior to the distillation step (ii) and the extraction step (iii). In some embodiments, the tobacco material is kept frozen and then defrosted until it reaches approximately room temperature (about 22°C), followed by the distillation step (ii) and the extraction step (iii).

[0063] In some preferred embodiments, the tobacco material is not subjected to any heat treatment prior to the distillation (ii) and extraction (iii) steps. For example, in some embodiments, the tobacco material is not heated to a temperature greater than approximately room temperature prior to the distillation (ii) and extraction (iii) steps. It has been found that by not subjecting the tobacco material to any heat treatment prior to the distillation (ii) and extraction (iii) steps, the loss of volatile compounds important to the aroma and taste of the extract can be reduced prior to the distillation (ii) and extraction (iii) steps.

[0064] Simultaneous distillation (ii) and extraction (iii) is a method commonly referred to in the art as simultaneous distillation-extraction (SDE). SDE provides a technique in which the separation and extraction of specific compounds from a sample can be performed simultaneously.

[0065] The SDE method is generally considered to have been established by Likens and Nickerson in 1964, who designed the original apparatus for analyzing hop oil (Likens ST, Nickerson GB, ...). ASBC Proc. , 1964, 5; A. Chaintreau, Flavour and Fragrance Journal (2001, 16: 136-148). In this method, the processes of steam distillation and extraction of volatiles from the sample into a small amount of solvent are combined. In the original Likens-Nickerson method, the following was used: Figure 1 The apparatus 1 shown is used to analyze hop oil. The sample (an aqueous solution or slurry of a solid material in water) is boiled in a flask connected to the left side arm 2 with stirring. The volatiles are then steam distilled through the upper part of the left side arm 2, while the solvent vapors are distilled through the upper part of the right side arm 3. The vapors condense on a cold finger condenser 4, and the extraction process begins between two liquid films on the condenser surface 5.

[0066] Steam distillation (SDE) has been found to be useful for separating volatile substances from natural products. In this technique, the material from which the volatile compounds should be removed is subjected to steam distillation, while the distilled compounds are extracted with a solvent.

[0067] Typical devices used for SDE are displayed Figure 2 It should be noted that the apparatus shown can be used in SDE methods where the solvent used is denser than water. For example... Figure 2 As shown, apparatus 10 includes a flask 11 for the tobacco sample, a flask 12 for the solvent, a water bath 13, and a heating / stirring pan 14 for heating the sample. Apparatus 10 may also typically include an auxiliary heating pan 15 to heat the tobacco sample to a temperature higher than the solvent, allowing for steam distillation. Tubes 16a and 16b each have an inner diameter of approximately 4 mm. During the process, the vapor condenses on a finger-shaped condenser 17, and the extraction process can begin between two liquid films on the condenser surface 18. The apparatus allows the distilled water and solvent to be returned to their respective flasks after the dispensing process. This makes it possible to obtain an extract ready for analysis using techniques such as gas chromatography at the end of the process.

[0068] In some embodiments, the distillation step (ii) and the extraction step (iii) (i.e., SDE) are carried out at a pH not greater than 2 for the total time period of the steps. The inventors have surprisingly discovered that when a pH not greater than 2 is used in the SDE process, the amount of volatile compounds extracted from the tobacco material increases.

[0069] In some embodiments, the solvent is a nonpolar solvent. In some embodiments, the solvent is a polar solvent. The term "polar solvent" as used herein refers to any solvent having a dielectric constant greater than or equal to 15. The term "nonpolar solvent" as used herein refers to any solvent having a dielectric constant less than 15.

[0070] In some implementations, the solvent is immiscible with water.

[0071] In some embodiments, the solvent comprises an organic-based solvent. In some embodiments, the solvent is an organic solvent. In some embodiments, the solvent is a nonpolar organic solvent. The term "organic" is understood by those skilled in the art. Generally, organic solvents are considered to be solvents containing carbon.

[0072] In some implementations, the solvent is a nonpolar solvent that is immiscible with water.

[0073] In some embodiments, the solvent is selected from n-butanol, cyclohexane, dichloromethane, ethyl acetate, heptane, hexane, methyl tert-butyl ether, 2-butanone, pentane, diisopropyl ether, diethyl ether, and mixtures thereof. In some embodiments, the solvent is selected from pentane, diethyl ether, and mixtures thereof. In some preferred embodiments, the solvent is a mixture of pentane and diethyl ether. The use of a mixture of pentane and ether is preferred because this solvent is non-toxic and can be readily replaced with ethanol after the extraction of the relevant volatile compounds has been achieved.

[0074] In some embodiments, the solvent is a mixture of pentane and diethyl ether, wherein the solvent comprises pentane and diethyl ether in a weight ratio of about 10:1 to about 1:10, such as about 5:1 to about 1:5, such as about 3:1 to about 1:3, such as 3:1 to 1:1, such as about 3:1 to about 2:1, such as about 2:1. In some embodiments, the solvent is a mixture of pentane and diethyl ether, wherein the solvent comprises pentane and diethyl ether in a weight ratio of about 3:1 to about 1:1. In some embodiments, the solvent is a mixture of pentane and diethyl ether, wherein the solvent comprises pentane and diethyl ether in a weight ratio of about 2:1.

[0075] In some embodiments, distillation step (ii) and extraction step (iii) (i.e., SDE) are carried out at a pH of no more than about 2. In some embodiments, distillation step (ii) and extraction step (iii) (i.e., SDE) are carried out at a pH of 0.5 to 2. In some embodiments, distillation step (ii) and extraction step (iii) (i.e., SDE) are carried out at a pH of 1 to 2. In some embodiments, distillation step (ii) and extraction step (iii) (i.e., SDE) are carried out at a pH of about 1.6.

[0076] The inventors have surprisingly discovered that when using a pH not greater than 2, the amount of volatile compounds extracted from tobacco materials increases. This has the advantage that the aroma obtained from the extract is more pronounced when incorporated into tobacco products (such as smoking / e-cigarette products and / or smokeless tobacco products), and while the tobacco aroma is still recognizable, a range of other desired aroma notes can be perceived when a large number of different compounds are extracted. The inventors have also surprisingly discovered that when the extraction method is carried out at a pH greater than 2, the pH tends to increase towards the end of the extraction process, thereby reducing the efficiency of the hydrolysis process. When using a pH of approximately 1.6, even with pH increases during the SDE method, the final pH does not exceed 2, thereby improving the efficiency of the process for any type of tobacco.

[0077] In some embodiments, a pH of no more than 2 is obtained by mixing the tobacco material with an acid. In some embodiments, the acid may be selected from hydrochloric acid, sulfuric acid, and mixtures thereof. In some embodiments, the acid is hydrochloric acid. Treatment with hydrochloric acid (HCl) is the most common hydrolysis method. This is due to the ease of use of this reagent, as it can be used in both liquid and gas phases. Furthermore, hydrochloric acid has many applications in the food industry because the Food and Agriculture Organization of the United Nations (FAO) permits its use as a food acidifier.

[0078] In some embodiments, prior to distillation step (ii) and extraction step (iii) (i.e., SDE), the tobacco material is mixed with an acid (e.g., HCl) at an elevated temperature (e.g., about 50°C to about 80°C) for no more than about 1 hour. In some embodiments, prior to distillation step (ii) and extraction step (iii) (i.e., SDE), the tobacco material is mixed with an acid (e.g., HCl) at an elevated temperature (e.g., about 50°C to about 70°C) for no more than about 45 minutes. In some embodiments, prior to distillation step (ii) and extraction step (iii) (i.e., SDE), the tobacco material is mixed with an acid (e.g., HCl) at an elevated temperature (e.g., about 60°C) for no more than about 30 minutes. In some embodiments, prior to distillation step (ii) and extraction step (iii) (i.e., SDE), the tobacco material is mixed with an acid (e.g., HCl) at a temperature of about 60°C for about 20 minutes.

[0079] In some embodiments, both distillation step (ii) and extraction step (iii) (i.e., SDE) are performed for approximately 8 to approximately 15 hours. In some embodiments, both distillation step (ii) and extraction step (iii) (i.e., SDE) are performed for approximately 8 to approximately 10 hours. In some embodiments, both distillation step (ii) and extraction step (iii) (i.e., SDE) are performed for approximately 9 hours. In some embodiments, both distillation step (ii) and extraction step (iii) (i.e., SDE) are performed for approximately 8 hours.

[0080] As those skilled in the art will understand, the typical time for SDE is approximately 5 hours. The inventors have surprisingly discovered that when SDE is performed for at least 8 hours (preferably for a period of at least 8 hours where the SDE method comprises only a single step), the concentration of volatile compounds in the resulting extract (or distillate) is significantly increased. This has the advantage that the sensory properties of the tobacco products are improved when incorporated into tobacco products (such as smoking / e-cigarette products and / or smokeless tobacco products), and the aroma obtained from the extract is more pronounced.

[0081] In some implementations, the distillation step (ii) and the extraction step (iii) (i.e., SDE) are carried out at a temperature of up to about 130°C.

[0082] In some embodiments, the distillation step (ii) is carried out at a temperature of about 100°C to about 130°C, such as about 105°C to about 125°C, such as about 110°C to about 125°C, such as about 115°C to about 125°C, such as about 120°C to about 122°C, such as about 121°C.

[0083] In some embodiments, the extraction step (iii) is performed at a temperature of about 50°C to about 100°C, such as about 60°C to about 95°C, such as about 70°C to about 90°C, such as about 75°C to about 90°C, such as about 80°C to about 90°C, such as about 85°C to about 90°C.

[0084] In some implementations, the distillation step (ii) and the extraction step (iii) (i.e., SDE) are carried out at atmospheric pressure.

[0085] In some embodiments, the distillation step (ii) and the extraction step (iii) are performed simultaneously in a single step. Thus, in some embodiments, the SDE method described herein is performed in only a single step. In some embodiments, no additional distillation and / or extraction steps are included. In some embodiments, the entire SDE method (i.e., the distillation step (ii) and the extraction step (iii)) is performed simultaneously in a single device, without further processing before the extracted product is removed from the device.

[0086] In some embodiments, one or more related volatile compounds extracted from tobacco materials are selected from: sugars, sugar esters, amino acids, β-carotene, violetin, lutein, neoxanthin, phytol, lysine, sipranones, polyphenols, lignin, and mixtures thereof.

[0087] In some embodiments, one or more related volatile compounds extracted from tobacco materials are selected from: methylbutanol, benzyl alcohol, phenethyl alcohol, methoxyvinylphenol, vinylphenol, hydroxydihydrodamascone, furfural, hydroxymethylfurfural, furanone, methylcyclopentenolone, dimethylpyrazine, trimethylpyrazine, tetramethylpyrazine, hydroxymethyl(methyl)pyrazine, isophorone, oxyisophorone, crocin, iononas, damascone, β-damascone, megastigmatrienone, etc. β-Dihydrodamasone, β-ionone, 2,6-nonadienal, 2-nonenal, linalool, linalool oxide, geranylacetone, farnesylacetone, methylheptadenone, solanone, solanine, norbornene lactone, ambroxol, succinate lactone, isobutyric acid, isovaleric acid, 3-methylvaleric acid, heptanoic acid, benzoic acid, phenylacetic acid, o-cresol, p-cresol, methylthiopropional, guaiacol, vinylphenol, ethylguaiacol, vinylguaiacol, eugenol, vanillin and mixtures thereof.

[0088] In some implementations, one or more related volatile compounds extracted from tobacco materials are associated with the characteristic taste or aroma of at least one tobacco variety.

[0089] In some embodiments, the extracts obtained from tobacco materials are substantially free of alkaloids and / or tobacco-specific nitrosamines (TSNAs).

[0090] As used herein, "substantially alkaloid-free" means that the extract contains less than about 15% by weight of alkaloids (such as nicotine), for example less than about 10% by weight of alkaloids (such as nicotine), for example less than about 5% by weight of alkaloids (such as nicotine), for example less than about 2% by weight of alkaloids (such as nicotine), for example less than about 1% by weight of alkaloids (such as nicotine), for example less than about 0.5% by weight of alkaloids (such as nicotine), for example less than about 0.1% by weight of alkaloids (such as nicotine). In some embodiments, the extract obtained from tobacco material contains less than about 1% by weight of alkaloids (such as nicotine).

[0091] To avoid being bound by theory, a pH of no more than 2 is used to allow any nicotine present in the tobacco material to react with hydrochloric acid (HCl) to form a water-soluble salt—nicotine hydrochloride. This salt is not extracted during the method of this invention.

[0092] As used herein, "substantially TSNA-free" means that the extract contains less than about 15% by weight of TSNA, for example less than about 10% by weight of TSNA, for example less than about 5% by weight of TSNA, for example less than about 2% by weight of TSNA, for example less than about 1% by weight of TSNA, for example less than about 0.5% by weight of TSNA, for example less than about 0.1% by weight of TSNA. In some embodiments, the extract obtained from tobacco material contains less than about 1% by weight of TSNA.

[0093] In some implementations, further processing of the extracted product can be performed after the distillation step (ii) and extraction step (iii) (i.e., SDE). It should be noted that this further processing is not considered an additional step in the SDE process itself, but rather an additional processing step on the distillate obtained from the SDE process.

[0094] Further processing can be carried out in a variety of ways. The methods of further processing may depend on the compounds present in the extract and / or the type of solvent used in the extraction. For example, in some embodiments, when one or more compounds are extracted from steam-distilled tobacco material using an organic nonpolar solvent (e.g., pentane, diethyl ether, or mixtures thereof), the solvent can be simply filtered or dried after contact with the distilled material to remove particulate tobacco material and the solvent, and the filtrate can be concentrated.

[0095] In some embodiments, further processing of the extracted product is carried out, including a purification step that involves replacing the solvent used for extraction with another solvent suitable for tobacco products. In some embodiments, such a purification step involves replacing the solvent used for extraction (e.g., pentane, diethyl ether, or mixtures thereof, preferably a 2:1 mixture of pentane and diethyl ether) with ethanol. Replacing the solvent with ethanol is desirable for use in tobacco products.

[0096] In some embodiments, further processing of the extract is carried out, which includes applying conditions to the isolated compound or mixture of these compounds that cause one or more of the compounds to undergo chemical transformation. For example, tobacco material obtained from a species of the genus *Nicotiana* or a portion thereof, as well as extracts containing one or more isolated compounds, can be treated to induce chemical transformation and / or mixed with other components. Chemical transformation or modification of the tobacco material, extract, or one or more isolated compounds can result in changes to certain chemical and physical properties of the tobacco material, extract, or one or more isolated compounds (e.g., its sensory properties). Exemplary chemical modification processes include acid / base reactions, hydrolysis, oxidation, heating, and / or enzymatic treatment. Due to these processes, the compounds may undergo various degradation reactions.

[0097] In some embodiments, one or more related volatile compounds extracted from tobacco material are degradation products selected from: sugars, glycolipids, amino acids, β-carotene, violetin, lutein, neoxanthin, phytol, lysine, sipranones, polyphenols, and lignin, and mixtures thereof. In some embodiments, such degradation products may be further processed to provide a variety of aroma compounds selected from methylbutanol, benzyl alcohol, phenethyl alcohol, methoxyvinylphenol, vinylphenol, hydroxydihydrodamascone, furfural, hydroxymethylfurfural, furanone, methylcyclopentenolone, dimethylpyrazine, trimethylpyrazine, tetramethylpyrazine, hydroxymethyl(methyl)pyrazine, isophorone, oxyisophorone, saffron aldehyde, ionone, β-damascone, megastigmatrienone, β-dihydrodamascone, etc. Damasone, β-ionone, 2,6-nonadienal, 2-nonenal, linalool, linalool oxide, geranylacetone, farnesylacetone, methylheptadenone, solanone, solanine, norbornene lactone, ambroxol, sage lactone, isobutyric acid, isovaleric acid, 3-methylvaleric acid, heptanoic acid, benzoic acid, phenylacetic acid, o-cresol, p-cresol, methylthiopropional, guaiacol, vinylphenol, ethyl guaiacol, vinyl guaiacol, eugenol, and vanillin.

[0098] As used herein, “degradation products” refers to any compound produced from compounds extracted and / or degraded according to the present invention. Degradation products may be formed naturally from such compounds or may be generated by accelerating the degradation process (e.g., by accelerating the decomposition of compounds through heat and / or the addition of chemicals). These compounds may be degraded, for example, by oxidation and / or hydrolysis reactions (e.g., by treatment with hydrochloric acid or other acidic reagents).

[0099] In some embodiments, the waste generated by the extraction methods described herein contains residual tobacco material. In some embodiments, the waste generated by the extraction methods described herein can be used as raw material for the production of reconstituted tobacco or briquettes.

[0100] Tobacco extract A second aspect of the invention provides a tobacco extract that is obtainable or acquired by the above method, wherein the tobacco extract contains one or more related volatile compounds in an amount of at least about 75% by weight of the tobacco extract.

[0101] In some implementations, the tobacco extract is obtained or acquired by a method comprising the following steps: i) Providing tobacco materials; ii) subjecting the tobacco material to steam distillation; and iii) Extract one or more related volatile compounds from the tobacco material using a solvent; The distillation step (ii) and the extraction step (iii) are carried out simultaneously at a pH not greater than 2, and the distillation step (ii) and the extraction step (iii) are carried out for a time of about 8 to about 20 hours; wherein the tobacco extract contains one or more related volatile compounds in an amount of at least about 75% by weight of the tobacco extract.

[0102] In some embodiments, the tobacco extract is obtained or acquired by the method defined in any of the embodiments described above.

[0103] In some embodiments, the tobacco extract contains one or more related volatile compounds in an amount of at least about 80% by weight, for example, at least about 85% by weight, for example, at least about 90% by weight, for example, at least about 95% by weight, for example, at least about 97% by weight.

[0104] In some embodiments, the tobacco extract contains one or more related volatile compounds in an amount of at least about 95% by weight of the tobacco extract.

[0105] In some embodiments, one or more associated volatile compounds in the tobacco extract are selected from: sugars, sugar esters, amino acids, β-carotene, violetin, lutein, neoxanthin, phytol, lysine, sipranones, polyphenols, lignin, and mixtures thereof.

[0106] In some embodiments, one or more associated volatile compounds in the tobacco extract are selected from: methylbutanol, benzyl alcohol, phenethyl alcohol, methoxyvinylphenol, vinylphenol, hydroxydihydrodamascone, furfural, hydroxymethylfurfural, furanone, methylcyclopentenolone, dimethylpyrazine, trimethylpyrazine, tetramethylpyrazine, hydroxymethyl(methyl)pyrazine, isophorone, oxyisophorone, saffron aldehyde, ionone, damascone, β-damascone, megastigmatrienone, β-dihydrodamascone. Ketones, β-ionone, 2,6-nonadienal, 2-nonenal, linalool, linalool oxide, geranylacetone, farnesylacetone, methylheptadenone, solanone, solanine, norbornene lactone, ambroxol, succinate lactone, isobutyric acid, isovaleric acid, 3-methylvaleric acid, heptanoic acid, benzoic acid, phenylacetic acid, o-cresol, p-cresol, methylthiopropional, guaiacol, vinylphenol, ethylguaiacol, vinylguaiacol, eugenol, vanillin and mixtures thereof.

[0107] In some embodiments, the tobacco extract is substantially free of alkaloids and / or tobacco-specific nitrosamines (TSNAs). In some embodiments, the tobacco extract is substantially free of nicotine and / or TNSAs.

[0108] As used herein, "substantially alkaloid-free" means that the tobacco extract contains less than about 15% by weight of alkaloids (such as nicotine), for example less than about 10% by weight of alkaloids (such as nicotine), for example less than about 5% by weight of alkaloids (such as nicotine), for example less than about 2% by weight of alkaloids (such as nicotine), for example less than about 1% by weight of alkaloids (such as nicotine), for example less than about 0.5% by weight of alkaloids (such as nicotine), for example less than about 0.1% by weight of alkaloids (such as nicotine). In some embodiments, the tobacco extract contains less than about 1% by weight of alkaloids (such as nicotine).

[0109] As used herein, "substantially TSNA-free" means that the tobacco extract contains less than about 15% by weight of TSNA, for example, less than about 10% by weight of TSNA, for example, less than about 5% by weight of TSNA, for example, less than about 2% by weight of TSNA, for example, less than about 1% by weight of TSNA, for example, less than about 0.5% by weight of TSNA, for example, less than about 0.1% by weight of TSNA. In some embodiments, the tobacco extract contains less than about 1% by weight of TSNA.

[0110] Tobacco products A third aspect of the invention provides a tobacco product comprising the tobacco extract as defined above.

[0111] In some implementations, tobacco products are smoking / e-cigarette products or smokeless tobacco products, electronic devices, heating devices or a combination of both, cigarettes, cigars or smokeless oral tobacco products.

[0112] In some implementations, the tobacco product is a smoking / e-cigarette product or a smokeless tobacco product. In some implementations, the tobacco product is a cigarette, a cigar, or a smokeless oral tobacco product.

[0113] Tobacco extracts can be used as components of tobacco products in a variety of ways. They can be used as components of processed tobacco. In some embodiments, tobacco extracts can be used in flavoring or additives applied to tobacco leaves, or in surface flavorings. Alternatively, tobacco extracts can be used as components of reconstituted tobacco materials. During the cigarette manufacturing process, tobacco extracts can be incorporated into cigarette filters (e.g., into filter rods, filter rod forming paper, or tipping paper) or into tobacco wrapping paper, preferably on the inner surface.

[0114] In some implementations, tobacco extract is included in tobacco products in the form of a flavorant, a liquid, or a combination thereof, or in the form of reconstituted tobacco that includes the tobacco extract.

[0115] In some embodiments, the tobacco product is an electronic device, a heating device, or a combination of both. In such embodiments, the application of the tobacco extract can be adapted to the corresponding characteristics of these technologies. For example, in some embodiments, the tobacco product is an electronic device (e.g., an electronic cigarette) containing a tobacco extract in the form of an inhalable liquid. In some embodiments, the tobacco product is a heating device containing a tobacco extract in the tobacco, filter, or consumable paper.

[0116] Depending on the desired function of the tobacco extract, the chemical composition of the extract, and the type of tobacco product to which the extract is added, the amount of tobacco product containing the tobacco extract can be any suitable amount. In some embodiments, the tobacco product contains the tobacco extract in an amount of about 0.0001% to about 15% based on the total dry weight of the tobacco product to which the extract is added. In some embodiments, the tobacco product contains the tobacco extract in an amount of about 0.01% to about 10% based on the total dry weight of the tobacco product to which the extract is added. In some embodiments, the tobacco product contains the tobacco extract in an amount of about 0.1% to about 5% based on the total dry weight of the tobacco product to which the extract is added.

[0117] Methods for preparing tobacco products A fourth aspect of the present invention provides a method for preparing the tobacco product described herein, the method comprising the following steps: (a) Preparation of tobacco extract according to the methods described herein; and (b) Combining the tobacco extract directly with a tobacco product and / or combining the tobacco extract with reconstituted tobacco and optionally combining the reconstituted tobacco with a tobacco product.

[0118] In some implementations, the method for preparing tobacco products includes the following steps: (a) Preparation of tobacco extract according to the methods described herein; and (b) Combine the tobacco extract directly with tobacco products.

[0119] In some implementations, the tobacco extract is combined directly with the tobacco product by adding the tobacco extract in its liquid form, by adding the tobacco extract in the form of a liquid feedstock, or by a combination thereof.

[0120] In some implementations, the method for preparing tobacco products includes the following steps: (a) Preparation of tobacco extract according to the methods described herein; and (b) Combining the tobacco extract with reconstituted tobacco and combining the reconstituted tobacco with tobacco products.

[0121] use A fifth aspect of the invention provides the use of tobacco extracts, as described herein, for improving the sensory properties of tobacco products.

[0122] In some implementations, the use of tobacco extracts that are available or obtained by the methods described herein for improving the sensory properties of tobacco products is provided.

[0123] In some implementations, the tobacco extracts described herein are used to enhance the flavor of tobacco products. Example

[0124] Example 1 use Figure 3 The apparatus shown is used to perform the method according to the invention. When the solvent used is less dense than water (e.g., pentane:ethyl ether (2:1)), Figure 3 The device shown is functional. Figure 3As shown, apparatus 20 includes a 100 mL flask 21 for the tobacco sample, a 2 mL flask 22 for the solvent, a water bath 23, and a heating / stirring pan 24 for heating the sample. Apparatus 20 also includes an auxiliary heating coil 25 to heat the tobacco sample to a temperature higher than that of the solvent, allowing for steam distillation. During this process, the vapor condenses on finger-shaped condensers 27, and the extraction process begins between two liquid films on the condenser surface 28. Tubes 26a and 26b each have an inner diameter of approximately 4 mm.

[0125] Towards Figure 3 In the 2 mL flask 22 of the apparatus shown, 1 mL of a pentane:ether (2:1) mixture and pumice fragments were added. In the 100 mL flask 21, 5 g of tobacco (dry basis; various grades of Burley and Virginia tobacco were used as the tobacco material, some considered high quality and others low quality), pumice fragments, redistilled water, and approximately 1 mL of hydrochloric acid (HCl 37%) were added to achieve the pH required for the aqueous solution in contact with the tobacco, and the volume of the solution was kept equal to 40 mL. Preliminary tests indicated that the tobacco should be contacted with the acid at approximately 60°C for 20 minutes to ensure that the required pH is maintained in the SDE system after the acid solution is mixed with the tobacco.

[0126] Then connect the two flasks 21 and 22 to the body of the apparatus and mix redistilled water with pentane: ether (2:1) until both liquids begin to return to their respective flasks.

[0127] Flasks 21 and 22 are placed in baths preheated to 100°C and 140°C, respectively, with the liquid level in the flasks slightly higher than the bath level. When the liquid in the flasks begins to boil, observe whether the temperature in the smaller bath stabilizes between 85°C and 90°C, and whether the temperature in the larger flask stabilizes between 120°C and 122°C. Adjust as necessary to complete the SDE process within the recommended temperature range.

[0128] Run the system for 9 hours, observing during this time whether the liquid level in the flask containing the extract remains constant. If necessary, add a little more pentane:ethyl ether (2:1) mixture through the side outlet of the system to ensure that the liquid level in the flask containing the extract remains constant.

[0129] After 9 hours, the device was removed from the water bath and cooled until the extract temperature equilibrated to room temperature. The extract was then transferred to a calibration tube and the volume was adjusted to 1.5 mL with a pentane:ethyl ether (2:1) mixture.

[0130] Pentane:Ether solution exchange yields ethanol Add 1.5 mL of anhydrous ethanol and pumice fragments to the tube containing the extract. Concentrate the solution to approximately 1.5 mL in a 60°C bath. When boiling stops, keep the tube in contact with the bath for another 30 minutes to ensure that pentane and diethyl ether have been removed. The pentane:ether solvent is thus replaced by ethanol, and the extract is now in an ethanol solution. The extract in ethanol can be injected directly into cigarettes, applied to tobacco before cigarette preparation, or used in electronic devices, heating devices, or dual-purpose devices for subsequent sensory evaluation.

[0131] It was found that adding 1 microliter of extract to cigarettes could significantly alter the sensory characteristics of the tobacco product's smoke, and even 0.5 microliters was considered an acceptable level of addition.

[0132] Considering that this addition level corresponds to the application of an extract obtained from 6 kg of tobacco to 3 tons of tobacco intended for cigarette manufacturing, it can be concluded that the extract is highly effective. Their stability can be said to be the same, as the extract was found to be able to be stored for six months without altering its properties.

[0133] Furthermore, it was found that the extracts obtained via SDE in acidic media exhibit great potential as cigarette flavorings due to their properties imparted to smoke. In addition, it was noted that the irritation was reduced, the intensity increased, and they enhanced the basic tobacco aromas (such as freshness and earthiness) without imparting artificial properties to cigarettes. Moreover, from a toxicological point of view, there were no problems with using these extracts as cigarette flavorings.

[0134] The same methods detailed above were used to evaluate the taste properties of the extract in capsules and tobacco products (such as electronic devices, heating devices, and dual-purpose devices), and the potential for application of the extract in such products was confirmed.

[0135] Example 2 To extract relevant volatile compounds from larger samples of tobacco material, methods such as... Figure 4 The apparatus 30 shown is used. In this embodiment, 2240 g of tobacco, 933 mL of 6N hydrochloric acid (466.5 mL of HCl 37% + 466.5 mL of water), 15 L of water, and 100 g of pumice (PA) are placed in a 24 L round-bottom flask 31 on a heating mantle. The mixture is carefully stirred with a glass rod to obtain a homogeneous mixture. 200 mL of a pentane:ethyl ether (2:1) mixture containing 5 g of pumice is placed in a smaller round-bottom flask 32.

[0136] Connect the SDE unit to the flask using clamps to ensure the system is stress-free. After connecting the flask to the unit, add a few drops of water (using a pipette) to the connector to aid sealing. Using a pipette, add water to the central part of the unit to raise the level on the left branch to near the return level.

[0137] Using a pipette, slowly add the pentane:diethyl ether (2:1) mixture through the wall into the main body of the apparatus until the liquid level on the right branch rises to the return level. If the return level cannot be reached while the system is vertical, tilt the apparatus slightly as needed.

[0138] Connect the condenser to the main body of the equipment and turn on the cooling system (commercially available ethanol: water - 2:1).

[0139] Two round-bottom flasks are heated. This heating is achieved by connecting a voltage controller to a heating mantle, where the two flasks are positioned in predetermined locations. These positions ensure that the temperature is sufficient to bring the liquids in the flasks to a boil without creating turbulence.

[0140] The 9-hour distillation begins when the solution in the smaller flask starts to reflux. During this period, the largest flask and the side arm of the apparatus are always covered with asbestos or aluminum foil.

[0141] The system needs to be monitored until it reaches equilibrium (both liquids are simultaneously distilled and returned to their respective flasks). If one of the solvent layers (pentane-ether or water) rises above its proper height and tends to move into the opposite flask, the system must be tilted slightly towards the side with excess solvent.

[0142] If the volume of pentane-ether decreases during the SDE process, more pentane-ether can be added from the top of the condenser using a pipette to restore the lost solution volume.

[0143] After a 9-hour distillation period, the heating was turned off, and the system was allowed to stand until boiling ceased. Once boiling ceased, the flask containing the pentane-ether was removed, and 45 mL of anhydrous ethanol was added to the mixture. The solution was concentrated in a distillation apparatus at 45°C until no further boiling was observed. The temperature was then increased to 65°C for 15 minutes. After these 15 minutes, the heating was turned off, and the system was allowed to cool until the solution reached room temperature. The solution was then transferred to a beaker and brought to a final volume of 45 mL with anhydrous ethanol. This final solution was then prepared for flavoring.

[0144] It should be noted that the above procedures are as follows: Figure 4 The experiment was conducted on the device shown. It was found on devices such as... Figure 5 The device 40 shown (which is only used in Example 1 for 5 grams of tobacco and is displayed) Figure 3 Performing this procedure on an expanded version of the equipment presents minor difficulties. For example, the distilled pentane and ether are difficult to return to the main body of the equipment due to the large amount of water entering the system below the distilled pentane and ether.

[0145] Therefore, it was designed Figure 4 The device shown, wherein Figure 5 The two condensers at the top of the device shown have been modified to distill water at an acceptable rate without losing more volatile compounds. When obtaining extracts from 2240 grams of tobacco, Figure 4 The device shown is designed to bypass the aforementioned problem. For example... Figure 4 As shown, the water and organic solvent containing the distilled compounds are condensed in separate condensers and only come into contact with each other after they have cooled. This allows the tobacco and acid solution to be heated in the desired manner without interfering with the return of the distilled ether and pentane.

[0146] Comparative Example 1 – Comparison of SDE method and Neutral Volatile Scan (NYS) Chromatograms of the extracts obtained by SDE and NVS were compared.

[0147] The NVS method assumes the separation of naturally occurring compounds in tobacco, and if the process leading to their separation is simple steam distillation, then virtually all substances present in the SDE extract should also be present in the NVS extract. Several Burley and Virginia tobacco grades were evaluated for comparison between extracts.

[0148] The procedure for tobacco analysis using the NVS method is as follows: 1. Add 300 mL of dichloromethane and 5.0 g of tobacco to a Soxhlet extractor (500 mL flask, Whatman 33×80 mm cellulose filter cartridge). Heat the flask in a water bath at 50–55 °C for 6.5 hours. If deemed appropriate, the extraction time can be extended to 16 hours. Throughout the extraction process, maintain the system under an inert atmosphere and cover the bottom of the apparatus with aluminum foil to prevent the extract from being exposed to light. Transfer the extract to a 500 mL separatory funnel and wash the flask with a small amount of dichloromethane. If the volume is less than 300 mL, add more dichloromethane to the extract.

[0149] To generate an inert atmosphere in the apparatus used for tobacco extraction and in the apparatus defined in steps 4 and 6 below, the apparatus outlet is connected to a glass tube with an inner diameter of 2.0 cm using a flexible tube, through which nitrogen gas is passed at a flow rate of approximately 100 mL / min. Before heating the system, the end of the glass tube is closed, and the apparatus connection is kept partially open to force nitrogen gas through the apparatus. After 15 minutes, the end of the glass tube is opened, and the connection is adjusted appropriately. To prevent uncondensed solvent from accumulating on the flexible tube during extraction or distillation (which would then flow back into the apparatus and contaminate it), the glass tube is held below its connection point with the apparatus, using a glass tube with an appropriate inner diameter, and the apparatus is modified (if necessary) so that the outlet to which the flexible tube is connected is tilted downwards.

[0150] 2. The extract was then partitioned six times with 150 mL of a pH 6.0 buffer solution containing 0.092 M Na₂HPO₄ and 0.48 M KH₂PO₄. The solutions were stirred for 15 seconds and allowed to stand for 5 minutes, then the aqueous phase was discarded. If the separation of the two phases was unclear at the interface, most of the organic phase was removed from the funnel, 10 mL of dichloromethane was added, and the mixture was stirred again and allowed to stand until complete separation of the two phases was achieved.

[0151] 3. After partitioning, pass the organic phase through a 2.5 × 200 mm glass column containing 50 g of anhydrous sodium sulfate. The column flow rate is approximately 5 mL / min. Wash the column with dichloromethane.

[0152] 4. Concentrate the solution in the apparatus described in step 1 above. Heat the flask in a water bath at 55-60°C, keeping the entire system in an inert atmosphere (as described in step 1 above), and prevent its exposure to light by covering the bottom of the system with aluminum foil. Reduce the extract volume to approximately 1 mL. Transfer the residue to a graduated tube and bring the volume to 4 mL with a 7.5% v / v ethanol dichloromethane solution.

[0153] 5. Add 1.75 g of a dichloromethane solution of 100-200 mesh Florisil and 7.5% v / v ethanol to a 15 cm × 15 mm inner diameter glass column. Remove excess solution until the liquid level is just above the Florisil level, and apply the extract obtained in step 4 onto it. Elute the resulting mixture with the same solution used in the column preparation and collect 40 mL.

[0154] 6. Add 40 mL of dichloromethane to the collected solution and concentrate the solution to approximately 1 mL as described in step 4 above. Add 60 μL of an ethanol solution of ethyl palmitate (internal standard), homogenize by manual stirring, and transfer the concentrate to a graduated tube. Make up the volume to 3 mL with dichloromethane.

[0155] 7. The extract was then analyzed by gas chromatography using a Hewlett-Packard chromatograph (model 5880A) under the following conditions: • Carrier gas: H2, 20 psi; t M 120℃, 0.70 minutes; split ratio 15:1. • Injection volume: 2 μL. • Sample introduction technique: The injection needle is filled with solvent and then the extract is aspirated, followed by injection using a hot needle technique, such as Grob, Jr, K. & Neurom, HP. J. High Resol. Chromat. Chromat. Comm., 15-21, 1979 As described in [the text]. • Integrator: Hewlett-Packard 3356B Laboratory Automation System. • Column: 25 m × 0.2 mm inner diameter, cross-linked methyl silicone; film thickness 0.50 micrometers, fused silica. • Column oven temperature distribution: Initial value—120℃; Initial time—0.00 minutes Level 1: ▪ Program speed: 1.50℃ / minute Final value: 155℃ ▪ Final time: 0.00 minutes Level 2: ▪ Program speed: 0.80℃ / minute Final value: 210℃ ▪ Final time: 0.00 minutes ○ Level 3 (Column Purging Time): ▪ Program speed: 30.00℃ / minute Final value: 300℃ ▪ Final time: 35 minutes • Detector: FID; 300℃; H2, 30 mL / min; Air, 300 mL / min; Nitrogen / replenishment, 30 mL / min • Injector: 200℃; mixing chamber type liner • Additional commands (executed automatically) ○ 90.00 minutes – Signal off (recorder) ○ 90.00 minutes – Injector temperature, 275°C ○ 115.00 minutes – Injector temperature, 200°C.

[0156] Using the method described in Example 1 for SDE, except for using a pH of 5.0-6.0, is inconsistent with the present invention.

[0157] Table 1 shows the results obtained from one of these comparisons, which confirms the above conclusion.

[0158] Table 1 – Comparison of the relative areas of the peaks of aroma compounds separated from Virginia-type tobacco by NVS and SDE methods compound NVS (Relative Area of ​​Chromatographic Peaks) SDE (relative area of ​​chromatographic peaks) Solanone 13.4 69.4 Damaskone 1.0 3.1 Solanol 1.3 9.8 β-Dihydrodamascone 1.0 6.8 Megastigmatrienone 86.0 258.8 Solanine sulfadiazine 1.0 32.7 *The sum of the megastigmatrienone isomers.

[0159] It can be seen that many substances in the extract obtained by SDE are either present in small amounts or not present at all in the NVS extract.

[0160] The compounds shown in Table 1, such as megastigmatrienone, solanone, and damascone, are very important flavorings. Their presence in large quantities in the SDE extract justifies the difference in flavor produced by the SDE extract compared to that produced by the NVS extract.

[0161] When the extracts were applied to tobacco products, it was found that the aroma of the extracts separated from tobacco by solvent extraction (i.e., NVS) was quite indistinct compared to the extracts separated by using the SDE method described herein.

[0162] Based on these results, and not wanting to be bound by theory, it appears that the following processes may occur when tobacco is processed in an SDE system: simple distillation, steam distillation, and degradation / steam distillation or degradation / simple distillation. Since the pH of the aqueous solution in contact with tobacco during the SDE process is in the range of 5.0 to 6.0, and because the tobacco is heated at approximately 100°C for several hours, degradation processes such as hydrolysis, dehydration, isomerization, and simple thermal degradation may occur. When these processes occur in an SDE system, they may produce products with properties different from those obtained in a closed system.

[0163] To avoid being bound by theories, such as those in closed systems, there is a tendency to obtain the most stable products and volatiles naturally present in or derived from tobacco, which have as many opportunities for chemical reaction as the least volatile substances. In SDE systems, volatiles have fewer opportunities for transformation because they are rapidly removed. Therefore, relatively unstable compounds, or even intermediates of the degradation process, can be isolated.

[0164] Comparative Example 2 – Comparison of SDEs performed at pH 6.0 and pH 2.0 To demonstrate the advantages of using a pH no greater than 2 in the SDE method, extracts obtained from SDE using pH values ​​of 2.0 and 6.0 were evaluated and compared.

[0165] The pH of the procedure was varied by using different amounts of HCl (e.g., 1 mL of 37% HCl to achieve a pH below 2), thereby using Virginia-type tobacco as the tobacco material in Example 1 at pH 2.0 (as described above) and at pH 6.0. The extracts thus obtained were separated by gas chromatography, and their chromatograms were compared.

[0166] For reference, Figure 6 The image shows an exemplary chromatogram that divides the peaks into three groups: volatile fragrances, semi-volatile fragrances, and diterpenes. It is worth noting that... Figure 6 For reference only, and to interpret the peaks in the chromatograms shown in this article.

[0167] Chromatograms obtained from the two SDE methods at pH = 2.0 and pH = 6.0 are shown in the figures below. Figure 7 (a) and Figure 7 (b) in. For example... Figure 7 As can be seen, at pH values ​​not exceeding 2, the formation of volatile compounds becomes highly favorable due to the significantly increased concentration of volatile compounds extracted at these pH levels. The changes in aroma are also quite pronounced. Comparing the two extracts, it is noted that the aroma obtained at pH values ​​not exceeding 2 is more pronounced; although the tobacco aroma is still discernible, a range of other aroma notes can also be perceived.

[0168] Table 2 – Comparison of the relative peak areas of aroma compounds separated from Virginia-type tobacco by SDE method at pH = 6.0 and pH = 2.0 compound pH 6.0 pH 2.0 Solanone 83.3 191.8 Damaskone 7.3 8.7 Norsolonadione 3.0 8.7 Megastigmatrienone 200.3 417.3 Solanine sulfadiazine 112.9 146.1 *The sum of the megastigmatrienone isomers.

[0169] Table 2 shows the relative areas of the various peaks present in the extracts obtained by SDE at pH 6.0 and pH 2.0, highlighting several flavoring compounds considered important, many of which are used in formulations for flavoring tobacco. Treatment at the lower pH 2 resulted in an increase in the peaks of all flavor compounds (i.e., higher concentrations). Furthermore, many other compounds with undetermined structures were extracted at higher concentrations at pH 2.0.

[0170] In addition, further experiments were conducted to determine the effectiveness of the SDE method at pH 2.0 when tobacco material was mixed with acid several hours before SDE compared to treating the tobacco material with acid before SDE.

[0171] In this further experiment, tobacco was treated with an acidic solution at approximately 90°C for several hours without removing volatile substances. The acid was then neutralized and SDE (sulfate-desorption process) was performed. The resulting extract exhibited a different chemical composition than that obtained by treating tobacco with an acidic solution concurrently with SDE. As an example, the content of solanones (one of the compounds whose formation increases with SDE treatment in an acidic medium) was lower in the extract obtained from tobacco that had already been adequately treated with acid before SDE and then subjected to SDE alone.

[0172] Comparative Example 3 – Comparison of SDEs at different pH ranges To further demonstrate the advantages of using a pH no greater than 2 in the SDE method, extracts obtained from SDE using a range of pH values ​​were evaluated and compared.

[0173] The method of Example 1 was performed on a series of samples, each using Virginia-type tobacco as the tobacco material in each sample, and the pH of the procedure was varied by changing the amount of HCl used, thus performing the method of Example 1 at different pH values. Extracts obtained by SDE at pH values ​​of 6.0, 4.0, 3.0, 2.0, and 0.5 were evaluated. The extracts thus obtained were separated by gas chromatography, and their chromatograms were compared.

[0174] exist Figure 8-12 The figure shows chromatograms obtained from the SDE method at various pH values.

[0175] from Figures 8 to 12 The comparison shows that at pH values ​​not greater than 2, the formation of volatile compounds increases significantly.

[0176] The resulting extracts were also tested as flavorings for cigarettes. For extracts produced using SDE at pH 2 or 0.5, even at very low addition levels, they imparted increased amplitude, reduced harshness, and enhanced aroma characteristics in the smoke, depending on the tobacco variety used to produce the extracts. Based on these results, it can be concluded that tobacco extracts obtained via SDE under acidic conditions have the potential to become commercially important, enabling, for example, the improvement of low-quality tobacco, the enhancement of aroma in low-tar cigarettes, and even their use in new technologies such as capsules or as tobacco flavoring agents for next-generation products, or simply the masking of undesirable sensory properties in such products.

[0177] Comparison of SDEs at different time periods in Example 4 To demonstrate the advantages of the SDE method, which takes approximately 8 to 20 hours, extracts obtained from SDE over a series of time periods were evaluated and compared.

[0178] The SDE method described in Example 1 was performed, but for a total time of 5 hours instead of the 9 hours in Example 1. Those skilled in the art will understand that 5 hours is generally considered a standard time period for extraction in SDE methods used to analyze tobacco.

[0179] The inventors discovered that a 5-hour SDE duration was insufficient for the quantitative removal of volatile compounds. In contrast, a 9-hour SDE resulted in higher concentrations of aroma compounds, thereby providing an enhanced aroma. The results obtained in this study indicate that the duration of SDE in an acidic medium significantly affects the chemical composition of the extract.

[0180] Regarding the sensory significance of compounds isolated after long-term (i.e., at least approximately 8 hours) SDE in acidic media, it was found that at least some of them contribute to the quality of smoking / vaping.

[0181] The various embodiments described herein are presented merely to aid in understanding and teaching the claimed features. These embodiments are provided only as representative examples of embodiments and are not exhaustive and / or exclusive. It is to be understood that the advantages, embodiments, examples, functions, features, structures and / or other aspects described herein should not be considered as limitations on the scope of the invention as defined by the claims or on its equivalents, and other embodiments may be utilized and modifications may be made without departing from the scope of the claimed invention. In addition to those specifically described herein, various embodiments of the invention may suitably comprise, consist of, or substantially consist of suitable combinations of the disclosed elements, components, features, parts, steps, devices, etc. Furthermore, this disclosure may include other inventions not currently claimed but which may be claimed in the future.

Claims

1. A method for preparing a tobacco extract for improving the sensory properties of tobacco products, the method comprising the following steps: i) Providing tobacco materials; ii) The tobacco material is subjected to steam distillation; and iii) Extracting one or more related volatile compounds from the tobacco material using a solvent, wherein the solvent is a mixture of pentane and diethyl ether; The distillation step (ii) and the extraction step (iii) are carried out simultaneously at a pH not greater than 2, and the duration of each step (ii) and the extraction step (iii) is 8 to 20 hours. The method further includes a purification step, which involves replacing the solvent used for extraction with another solvent suitable for the tobacco product.

2. The method according to claim 1, wherein the distillation step (ii) and the extraction step (iii) are carried out at a pH not greater than 2 for the total time period of the steps.

3. The method according to claim 1 or 2, wherein the solvent comprises pentane and diethyl ether in a weight ratio of 3:1 to 1:1 of pentane to diethyl ether.

4. The method according to claim 1 or 2, wherein the distillation step (ii) and the extraction step (iii) are carried out at a pH of 0.5 to 2.

5. The method according to claim 1 or 2, wherein the distillation step (ii) and the extraction step (iii) are carried out at a pH of approximately 1.

6.

6. The method according to claim 1 or 2, wherein both the distillation step (ii) and the extraction step (iii) are performed for 8 to 10 hours.

7. The method according to claim 1 or 2, wherein both the distillation step (ii) and the extraction step (iii) are performed for approximately 9 hours.

8. The method according to claim 1 or 2, wherein the distillation step (ii) and the extraction step (iii) are carried out at a temperature of up to 130°C.

9. The method according to claim 1 or 2, wherein the tobacco material does not undergo any heat treatment prior to the distillation step (ii) and the extraction step (iii).

10. A tobacco extract obtained by the method defined in any one of claims 1 to 9, wherein the tobacco extract comprises one or more related volatile compounds in an amount of at least 75% by weight of the tobacco extract.

11. The tobacco extract of claim 10, wherein the tobacco extract comprises one or more related volatile compounds in an amount of at least 90% by weight of the tobacco extract.

12. The tobacco extract according to claim 10 or 11, wherein the tobacco extract comprises one or more related volatile compounds in an amount of at least 95% by weight of the tobacco extract.

13. The tobacco extract according to claim 10 or 11, wherein the one or more associated volatile compounds are selected from: sugars, sugar esters, amino acids, β-carotene, violetin, lutein, neoxanthin, phytol, lysine, sipranones, polyphenols, lignin, and mixtures thereof.

14. The tobacco extract according to claim 10 or 11, wherein the one or more associated volatile compounds are selected from: methylbutanol, benzyl alcohol, phenethyl alcohol, methoxyvinylphenol, vinylphenol, hydroxydihydrodamascone, furfural, hydroxymethylfurfural, furanone, methylcyclopentenolone, dimethylpyrazine, trimethylpyrazine, tetramethylpyrazine, hydroxymethyl(methyl)pyrazine, isophorone, oxyisophorone, crocin, ionone, damascone, β-damascone, megastigmatrienone, etc. β-Dihydrodamasone, β-ionone, 2,6-nonadienal, 2-nonenal, linalool, linalool oxide, geranylacetone, farnesylacetone, methylheptadenone, solanone, solanine, norbornene lactone, ambroxol, succinate lactone, isobutyric acid, isovaleric acid, 3-methylvaleric acid, heptanoic acid, benzoic acid, phenylacetic acid, o-cresol, p-cresol, methylthiopropional, guaiacol, vinylphenol, ethylguaiacol, vinylguaiacol, eugenol, vanillin and mixtures thereof.

15. A tobacco product comprising a tobacco extract as defined in any one of claims 10 to 14.

16. The tobacco product of claim 15, wherein the tobacco extract is contained in the tobacco product in the form of a flavoring agent, a liquid, or a combination thereof, or in the form of reconstituted tobacco containing the tobacco extract.

17. The tobacco product according to claim 15 or 16, wherein the tobacco product is a smoking article or a smokeless tobacco product, an electronic cigarette, a heating device or a dual-use version of both, a cigarette, a cigar or a smokeless oral tobacco product.

18. A method for preparing a tobacco product as defined in any one of claims 15 to 17, comprising the following steps: (a) Preparing a tobacco extract according to any one of claims 1 to 9; and (b) Combining the tobacco extract directly with a tobacco product and / or combining the tobacco extract with reconstituted tobacco and optionally combining the reconstituted tobacco with a tobacco product.

19. Use of the tobacco extract as defined in any one of claims 10 to 14 for improving the sensory properties of tobacco products.

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