阅读说明：本技术 液体烟草提取物、制备方法和包含所述液体烟草提取物的气溶胶生成制品 (Liquid tobacco extract, method of making and aerosol-generating article comprising the same ) 是由 M·比亚斯奥利 M·法里纳 F·夫劳恩多弗 J·库克 S·兰纳斯佩泽 S·劳恩斯坦因 B 于 2020-06-05 设计创作，主要内容包括：本发明提供了一种包含高比率的期望化合物与非期望化合物的液体烟草提取物。所述液体烟草提取物包含非水性溶剂、基于所述液体烟草提取物的重量计至少0.2重量％的尼古丁、以及重量比大于0.25的(β-紫罗酮+β-大马酮)与(苯酚)。还提供一种通过包括以下步骤的方法制备的液体烟草提取物：在介于100摄氏度与160摄氏度之间的提取温度下加热烟草起始材料至少90分钟；收集在加热步骤期间从烟草起始材料释放的挥发性化合物；以及形成包含所收集的挥发性化合物的液体烟草提取物。(The present invention provides a liquid tobacco extract comprising a high ratio of desired compounds to undesired compounds. The liquid tobacco extract comprises a non-aqueous solvent, at least 0.2 wt% nicotine based on the weight of the liquid tobacco extract, and a weight ratio of (beta-ionone + beta-damascone) to (phenol) of greater than 0.25. Also provided is a liquid tobacco extract prepared by a process comprising the steps of: heating the tobacco starting material at an extraction temperature of between 100 ℃ and 160 ℃ for at least 90 minutes; collecting volatile compounds released from the tobacco starting material during the heating step; and forming a liquid tobacco extract comprising the collected volatile compounds.)

1. A liquid tobacco extract comprising a non-aqueous solvent, at least 0.2 wt% nicotine based on the weight of the liquid tobacco extract, and a weight ratio of (beta-ionone + beta-damascone) to (phenol) of greater than 0.25.

2. The liquid tobacco extract of claim 1, further comprising water, wherein the liquid tobacco extract comprises greater than 20 weight percent water based on the weight of the liquid tobacco extract.

3. The liquid tobacco extract according to claim 2, wherein the liquid tobacco extract comprises at least about 40% by weight water based on the weight of the liquid tobacco extract, preferably from 40% to 70% by weight water based on the weight of the liquid tobacco extract.

4. The liquid tobacco extract of claim 1, further comprising water, wherein the liquid tobacco extract is a concentrated tobacco extract comprising less than or equal to about 20 weight percent water, preferably from 8 to 15 weight percent water, based on the weight of the concentrated tobacco extract.

5. Liquid tobacco extract according to any one of claims 1 to 4, wherein the weight ratio of (β -ionone + β -damascone) to (phenol) is greater than 0.5, more preferably greater than 1, even more preferably greater than 1.5, most preferably greater than 2, such as between 2 and 10 or between 2 and 5.

6. The liquid tobacco extract according to any one of claims 1 to 5, wherein the liquid tobacco extract comprises from 0.4% to 3.6% by weight nicotine based on the weight of the liquid tobacco extract.

7. Liquid tobacco extract according to any one of claims 1 to 6, further comprising (β -ionone + β -damascone) and (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600)) in a weight ratio of more than 1.5.

8. The liquid tobacco extract according to any preceding claim, wherein the liquid tobacco extract is derived from burley tobacco and flue-cured tobacco.

9. The liquid tobacco extract of claim 8, wherein the cured tobacco is one or more of oriental tobacco and flue-cured tobacco.

10. The liquid tobacco extract according to any preceding claim, wherein the liquid solvent is glycerol, propylene glycol, triacetin, 1, 3-propanediol, or a mixture thereof.

11. The liquid tobacco extract according to any preceding claim, further comprising one or more of furanones, 2, 3-diethyl-5-methylpyrazine, acetic acid, vanillin, 2-ethyl-3, 5-dimethylpyrazine, 2-methylbutyric acid, 3-methyl-2, 4-nonanedione, 2-methoxyphenol, 2-phenylethanol, eugenol, and fenugreek lactone.

12. The liquid tobacco extract according to any preceding claim, wherein the liquid tobacco extract comprises at least 300 micrograms of acetic acid per gram of the liquid tobacco extract.

13. A cartridge comprising

A nicotine composition, wherein the nicotine composition comprises the liquid tobacco extract of any preceding claim.

14. A liquid tobacco extract comprising a non-aqueous solvent, nicotine, and a weight ratio of (β -ionone + β -damascone) to (phenol) of greater than 0.25, prepared by a process comprising the steps of:

heating the tobacco starting material at an extraction temperature of between 100 ℃ and 160 ℃ for at least 90 minutes;

collecting volatile compounds released from the tobacco starting material during the heating step; and

forming a liquid tobacco extract comprising the collected volatile compounds.

15. The liquid tobacco extract of claim 14, wherein the liquid tobacco extract further comprises water, and the method further comprises:

drying the liquid tobacco extract to obtain a concentrated tobacco extract.

Technical Field

The present invention relates to liquid tobacco extracts.

Background

Aerosol-generating systems for delivering an aerosol to a user are known, the aerosol-generating systems comprising a nebulizer configured to generate an inhalable aerosol from a liquid composition, such as a liquid nicotine composition. Some known aerosol-generating systems include a thermal atomizer, such as an electric heater, configured to heat and vaporize a liquid composition to generate an aerosol. One popular type of electrically heated aerosol-generating system is an electronic cigarette. Other known aerosol-generating systems include non-thermal atomizers configured to generate aerosols from liquid compositions using, for example, impinging jet, ultrasonic, or vibrating screen techniques.

Liquid tobacco extracts can be prepared by an extraction process in which nicotine and other volatile flavor compounds are extracted from tobacco material and collected in a suitable solvent.

Methods of producing liquid tobacco extracts from tobacco material are known.

Liquid tobacco extracts can be produced by a high temperature extraction process in which nicotine and other volatile flavor compounds are extracted from tobacco material and collected in a suitable solvent to form a natural liquid tobacco extract.

For example, processes are known in which tobacco material is substantially boiled in water for hours or even days to form a vapour phase, and the distillate obtained by condensing the vapour phase is collected in a vessel. Over time, an oily wax-like layer containing a high proportion of nonpolar compounds accumulates at the surface of the distillate.

The waxy layer is built up on and the aqueous fraction containing nicotine and other water-soluble compounds is recycled to the boiler. A non-polar co-solvent may optionally be added to the boiler along with the aqueous portion to improve extraction yield. On the other hand, the waxy phase is collected and ultimately forms the main product of one such water distillation process. Such products are commonly referred to as "tobacco essential oils" and contain a high proportion of non-polar compounds found in tobacco, such as fatty acids, neophytadiene, and the like. The tobacco essential oil obtained by one such process is generally free of nicotine.

It is also known to subject tobacco material to an extraction process involving the use of volatile non-polar solvents. Examples of suitable solvents are cyclic or acyclic short-chain alkanes, and chlorinated solvents such as dichloromethane. In one such process, excess solvent may be evaporated by controlled heating under vacuum. Typically, this is done in the presence of ethanol, which has a higher boiling point than the extraction solvent, so that even trace amounts of extraction solvent can be detected.

One such major product of a solvent-assisted extraction process is commonly referred to as "tobacco absolute", and may contain trace amounts of ethanol. It is a waxy product containing a high concentration mixture of mostly non-polar compounds that can be extracted with a specific solvent, usually including nicotine, which is usually present in relatively high concentrations.

An alternative extraction process involves contacting the tobacco material with a solvent under supercritical conditions, such as supercritical carbon dioxide. One such process is disclosed in US 2013/160777 and relies on the principle that volatile substances in a feed contacted with a supercritical fluid can partition into the supercritical phase. After any soluble material is dissolved, the supercritical fluid containing the dissolved substance can be removed, and the dissolved components of the feed substance can be separated from the supercritical fluid. The main product of the supercritical extraction process is substantially similar to the "tobacco absolute" of a solvent assisted extraction process operating at lower temperatures and pressures, is free of residual solvent, and typically has high levels of waxy, non-polar compounds, and includes nicotine, which is typically present in relatively high concentrations.

In another type of extraction process, the tobacco material is soaked in a suitable solvent, such as an aerosol former, at or below room temperature for a period of several weeks in order to extract the tobacco components into the solvent. In one such process, commonly referred to as a cold impregnation process, the tobacco material remains suspended in the extraction liquid for a period of up to weeks or even months. The resulting slurry is then filtered and the liquid phase collected thereby can be used to produce a liquid composition for use in an aerosol-generating system. However, in one such process, it is often difficult to control the extraction conditions (e.g., temperature and pressure). In addition, the liquid phase collected upon filtration of the slurry, which represents the primary product of the cold impregnation process, is highly diluted and tends to have low levels of non-polar tobacco flavors. In addition, the liquid phase typically contains little to no nicotine. Thus, the liquid extract obtained by the cold infusion process usually needs to be supplemented with additional ingredients, such as nicotine salts and glycerol, before being used in an aerosol-generating system.

The liquid tobacco extract obtained by this known extraction process may have low levels of nicotine. Furthermore, the liquid tobacco extract obtained by such an extraction process may have a low content and a low variety of flavour substances, in particular with respect to compounds related to the flavour of heated tobacco, such as furanones. Liquid tobacco extracts obtained by such extraction processes may also contain high levels of undesirable compounds. In general, the concentration of nicotine, flavors, and undesirable compounds obtained by such extraction processes can be significantly affected by one or more types of tobacco used as starting material.

Disclosure of Invention

It is an object of the present invention to reduce one or more of the disadvantages of liquid tobacco extracts obtained by known processes. It is particularly desirable to produce new and improved liquid tobacco extracts.

The present disclosure relates to a liquid tobacco extract. The liquid tobacco extract preferably comprises a non-aqueous solvent. The liquid tobacco extract preferably comprises at least 0.2% by weight nicotine. The liquid tobacco extract preferably comprises (beta-ionone + beta-damascone) and (phenol) in a weight ratio of greater than 0.25.

The present disclosure also relates to a cartridge comprising a nicotine composition, wherein the nicotine composition comprises a liquid tobacco extract. The present disclosure also relates to a liquid tobacco extract prepared by a method comprising the step of heating a tobacco starting material at an extraction temperature of between 100 degrees celsius and 160 degrees celsius for at least 90 minutes.

According to the present invention, there is provided a liquid tobacco extract comprising a non-aqueous solvent, at least 0.2 wt% nicotine based on the weight of the liquid tobacco extract, and a weight ratio of (beta-ionone + beta-damascone) to (phenol) of greater than 0.25.

A liquid tobacco extract comprising a non-aqueous solvent, nicotine, and a weight ratio of (beta-ionone + beta-damascone) to (phenol) greater than 0.25 can be prepared by a process comprising the steps of: heating the tobacco starting material at an extraction temperature of between 100 ℃ and 160 ℃ for at least 90 minutes; collecting volatile compounds released from the tobacco starting material during the heating step; and forming a liquid tobacco extract comprising the collected volatile compounds.

The present inventors have found that liquid tobacco extracts according to the present invention have significantly higher levels of compounds associated with the flavour of heated tobacco than the products of the prior extraction processes discussed above. These compounds are substantially absent or present in trace amounts in tobacco extracts obtained by the impregnation process, which typically also contain little to no nicotine. These compounds are also generally absent or present in trace amounts in the tobacco extract obtained using the solvent, including under supercritical conditions. Similarly, tobacco essential oils obtained by distillation processes also typically have very low levels of such compounds, if any, associated with the flavor of heated tobacco. The liquid tobacco extract may be produced from a tobacco starting material consisting of a single type of natural tobacco. The tobacco starting material may comprise a blend of two or more types of natural tobacco. Alternatively, the liquid tobacco extract may be produced from a blend produced from a first tobacco starting material consisting of a first single type of natural tobacco extracted to form a first extract and a second tobacco starting material consisting of a second single type of natural tobacco extracted to form a second extract, wherein the first extract and the second extract are blended to form the liquid tobacco extract. Two or more extracts may be blended in this manner to form a liquid tobacco extract. The ratio of the different tobacco types may be adjusted according to the desired aerosol characteristics. For example, the proportion of burley tobacco may be increased when it is desired to provide relatively high levels of nicotine.

The liquid tobacco extract may comprise a non-aqueous solvent, water, nicotine, and flavor compounds. The liquid tobacco extract may advantageously be used directly to provide a nicotine composition for use in an electronic cigarette or other aerosol-generating system. The liquid tobacco extract resulting from the extraction process can be used to provide a nicotine composition without the addition of additional nicotine. The liquid tobacco extract resulting from the extraction process can be used to provide a nicotine composition without the addition of additional flavor compounds. The liquid tobacco extract resulting from the extraction process can be used to provide a nicotine composition without the addition of additional non-aqueous solvents. The liquid tobacco extract resulting from the extraction process can be used to provide a nicotine composition without the addition of additional water.

For example, the liquid tobacco extract resulting from the extraction process can be used to prepare a nicotine composition comprising 10 to 20mg nicotine per ml without the need for adding nicotine. The term "liquid tobacco extract" describes the direct product of an extraction process from tobacco material. Thus, liquid tobacco extracts typically comprise a mixture of natural components that are separated, removed, or derived from natural tobacco material using tobacco extraction processing conditions and techniques. Thus, in one such process, the extracted tobacco components are removed from the natural tobacco material and separated from the unextracted tobacco components. Thus, the liquid tobacco extract consists of a mixture of natural tobacco components that are derived from the tobacco starting material and that are extracted or formed in an extraction process, typically in combination with one or more materials other than the tobacco starting material, such as the extraction solvent used in the extraction process. The extraction solvent is preferably an aerosol former.

As used herein, the term "aerosol former" refers to a compound or mixture of compounds that, in use, promotes aerosol formation and is preferably substantially resistant to thermal degradation at the operating temperature of the aerosol-generating article or device. Examples of suitable aerosol-forming agents include: polyhydric alcohols such as propylene glycol, triethylene glycol, 1, 3-propanediol, 1, 3-butanediol, and glycerin; esters of polyhydric alcohols, such as monoacetin, diacetin, or triacetin; and aliphatic esters of monocarboxylic, dicarboxylic or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate.

The liquid tobacco extract may have a nicotine content of at least 0.2 wt%. More preferably, the nicotine content in the liquid tobacco extract is at least about 0.4% by weight. The nicotine content of the liquid tobacco extract can be no more than about 10% by weight, more preferably no more than about 8% by weight, more preferably no more than about 5% by weight, and most preferably no more than about 3.6% by weight. Most preferably, the liquid tobacco extract comprises about 0.4 to 3.6 weight percent nicotine based on the weight of the liquid tobacco extract.

One skilled in the art will appreciate that, when weight percentages of a particular component are disclosed herein with reference to a liquid tobacco extract, a concentrated tobacco extract, or a nicotine composition, the weight percentages are based on the weight of the particular component relative to the total weight of the respective liquid tobacco extract, concentrated tobacco extract, or nicotine composition.

The liquid tobacco extract may have a non-aqueous extraction solvent content of about 25% to about 65% by weight, preferably about 30% to 60% by weight, most preferably about 35% to about 55% by weight. The non-aqueous extraction solvent is preferably triacetin, glycerol, propylene glycol, 1, 3-propanediol, or a mixture thereof.

The liquid tobacco extract may comprise propylene glycol in a total content of about 25% to about 65% by weight, preferably about 30% to 60% by weight, most preferably about 35% to about 55% by weight.

The liquid tobacco extract may comprise triacetin in a total content of about 25% to about 65% by weight, preferably about 30% to 60% by weight, most preferably about 35% to about 55% by weight.

The liquid tobacco extract may comprise glycerin in a total content of about 25% to about 65% by weight, preferably about 30% to 60% by weight, most preferably about 35% to about 55% by weight.

The liquid tobacco extract may comprise 1, 3-propanediol in a total amount of about 25% to about 65%, preferably about 30% to 60%, most preferably about 35% to about 55%, by weight.

The extraction process provides a liquid tobacco extract comprising greater than about 20% by weight water, based on the weight of the liquid tobacco extract. Typically, the liquid tobacco extract may comprise at least about 40% by weight water. The liquid tobacco extract may comprise from about 40% to about 70% by weight water.

The liquid tobacco extract is preferably produced using an extraction process with an extraction temperature within a particular range, in combination with a particular defined duration of heating, which advantageously provides an improved liquid tobacco extract with a significantly improved balance of desired and undesired compounds. In particular, the extraction method provides a liquid tobacco extract having a maximized ratio of desired compounds to undesired compounds of the tobacco starting material. For example, using a particular combination of extraction temperatures and times as defined enables the levels of nicotine and flavor compounds to be optimized while also minimizing the levels of undesirable compounds such as furans, phenols and phenolic compounds and Tobacco Specific Nitrosamines (TSNAs).

Thus, the liquid tobacco extract obtained by one such process presents significant compositional differences relative to tobacco extracts obtained by existing extraction processes, and can be used as, or to prepare, an e-liquid that, when heated, produces an aerosol having different composition and flavor characteristics than currently available e-liquids. In particular, the tobacco extract obtained by the method according to the invention may be used to produce an aerosol that provides a heated tobacco taste that more closely resembles an aerosol produced by a conventional cigarette or by heating tobacco in a heated non-burning device, relative to available aerosols produced by existing liquid nicotine compositions.

The liquid tobacco extract was analyzed by gas chromatography to determine the content of the liquid. The weight of each compound within the liquid tobacco extract may be reported in micrograms per gram of liquid tobacco extract. The weight ratio of the compounds within the liquid tobacco extract as described herein can then be calculated.

In the liquid tobacco extract of the present invention, the weight ratio of (beta-ionone + beta-damascone) to (phenol) is greater than 0.25. The above ratio is higher when higher amounts of the fragrance compounds beta-ionone and beta-damascone are desired, or when the amount of phenol is lower.

Preferably, the first weight ratio of (beta-ionone + beta-damascone) to (phenol) is greater than 0.5, more preferably greater than 1, even more preferably greater than 1.5, most preferably greater than 2, for example between 2 and 10 or between 2 and 5.

The liquid tobacco extract of the invention may comprise (beta-ionone + beta-damascenone) and (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600)) in a weight ratio of greater than 1.5.

The above ratio is higher when higher amounts of the fragrance compounds beta-ionone and beta-damascone are desired, or when lower amounts of TSNA and 2-furancarbinol are desired.

The weight ratio of (beta-ionone + beta-damascone) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600)) may be greater than 0.2, such as greater than 0.5, for example between about 1 and about 10 or between about 1.5 and about 6. Preferably, the weight ratio is between about 2 and about 4.

The liquid tobacco extract may contain other desirable compounds derived directly from natural tobacco, many of which are flavors. The liquid tobacco extract may comprise one or more of furanone, 2, 3-diethyl-5-methylpyrazine, acetic acid, vanillin, 2-ethyl-3, 5-dimethylpyrazine, 2-methylbutyric acid, 3-methyl-2, 4-nonanedione, 2-methoxyphenol, 2-phenylethanol, eugenol, and fenugreek lactone (sotolone).

The liquid tobacco extract comprises beta-ionone. The liquid tobacco extract may comprise at least 0.100 micrograms of beta-ionone per gram of liquid tobacco extract, preferably at least 0.200 micrograms of beta-ionone per gram of liquid tobacco extract, more preferably at least 0.300 micrograms of beta-ionone per gram of liquid tobacco extract, most preferably at least 0.400 micrograms of beta-ionone per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 0.500 micrograms of beta-ionone per gram of liquid tobacco extract, more preferably at least 0.600 micrograms of beta-ionone per gram of liquid tobacco extract, even more preferably at least 0.700 micrograms of beta-ionone per gram of liquid tobacco extract, most preferably at least 0.800 micrograms of beta-ionone per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 0.9 micrograms of beta-ionone per gram of liquid tobacco extract, preferably at least 1.00 micrograms of beta-ionone per gram of liquid tobacco extract, more preferably at least 1.10 micrograms of beta-ionone per gram of liquid tobacco extract, even more preferably at least 1.20 micrograms of beta-ionone per gram of liquid tobacco extract, most preferably at least 1.30 micrograms of beta-ionone per gram of liquid tobacco extract. The weight ratio of (beta-ionone) to (phenol) may be greater than 0.150, such as greater than 0.200, preferably greater than 0.400, more preferably greater than 0.600, most preferably greater than 0.800, such as greater than 1.20. The weight ratio of (beta-ionone) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.300, such as greater than 0.500, preferably greater than 0.750, more preferably greater than 1.00, most preferably greater than 1.20, such as greater than 1.80.

The liquid tobacco extract comprises beta-damascenone. The liquid tobacco extract may comprise at least 0.100 micrograms of beta-damascenone per gram of liquid tobacco extract, preferably at least 0.350 micrograms of beta-damascenone per gram of liquid tobacco extract, more preferably at least 0.600 micrograms of beta-damascenone per gram of liquid tobacco extract, most preferably at least 0.850 micrograms of beta-damascenone per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 1.10 micrograms of beta-damascenone per gram of liquid tobacco extract, more preferably at least 1.35 micrograms of beta-damascenone per gram of liquid tobacco extract, even more preferably at least 1.60 micrograms of beta-damascenone per gram of liquid tobacco extract, most preferably at least 1.85 micrograms of beta-damascenone per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 2.10 micrograms of beta-damascenone per gram of liquid tobacco extract, preferably at least 2.35 micrograms of beta-damascenone per gram of liquid tobacco extract, more preferably at least 2.60 micrograms of beta-damascenone per gram of liquid tobacco extract, even more preferably at least 2.75 micrograms of beta-damascenone per gram of liquid tobacco extract, most preferably at least 2.90 micrograms of beta-damascenone per gram of liquid tobacco extract. The weight ratio of (β -damascenone) to (phenol) may be greater than 0.250, such as greater than 0.300, preferably greater than 0.700, more preferably greater than 1.00, most preferably greater than 1.30, such as greater than 1.60. The weight ratio of (β -damascenone) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.300, such as greater than 0.700, preferably greater than 1.00, more preferably greater than 1.50, most preferably greater than 2.20, such as greater than 2.70.

The weight ratio of (beta-ionone + beta-damascenone) to (nicotine) may be greater than 5.00 x 10^-5E.g. greater than 1.00X 10^-4Preferably greater than 2.00X 10^-4More preferably greater than 4.00X 10^-4Most preferably greater than 6.00X 10^-4E.g. greater than 7.00X 10^-4。

The liquid tobacco extract may comprise furanones. The liquid tobacco extract may comprise at least 0.0100 micrograms of furanones per gram of the liquid tobacco extract, preferably at least 0.100 micrograms of furanones per gram of the liquid tobacco extract, more preferably at least 0.300 micrograms of furanones per gram of the liquid tobacco extract, most preferably at least 0.500 micrograms of furanones per gram of the liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 0.700 micrograms of furanones per gram of liquid tobacco extract, more preferably at least 0.900 micrograms of furanones per gram of liquid tobacco extract, even more preferably at least 1.10 micrograms of furanones per gram of liquid tobacco extract, most preferably at least 1.30 micrograms of furanones per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 1.50 micrograms of furanones per gram of the liquid tobacco extract, preferably at least 1.80 micrograms of furanones per gram of the liquid tobacco extract, more preferably at least 2.00 micrograms of furanones per gram of the liquid tobacco extract, even more preferably at least 2.20 micrograms of furanones per gram of the liquid tobacco extract, most preferably at least 2.40 micrograms of furanones per gram of the liquid tobacco extract. The weight ratio of (furanone) to (phenol) may be greater than 0.400, such as greater than 0.600, preferably greater than 0.800, more preferably greater than 1.00, most preferably greater than 1.10, such as greater than 1.30. The weight ratio of (furanone) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.600, such as greater than 0.800, preferably greater than 1.00, more preferably greater than 1.50, most preferably greater than 2.00, such as greater than 2.10.

The liquid tobacco extract may comprise 2, 3-diethyl-5-methylpyrazine. The liquid tobacco extract may comprise at least 3.00 x 10^-3Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, preferably at least 5.00X 10^-3Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, more preferably at least 9.00X 10^-3Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, most preferably at least 1.50X 10^-2Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 2.50 x 10^-2Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, more preferably at least 3.50X 10^-2Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, even more preferably at least 5.00X 10^-2Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, most preferably at least 7.50X 10^-2Microgram of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 9.00X 10^-2Micrograms of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, preferably at least 0.100 micrograms of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, more preferably at least 0.200 micrograms of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, even more preferably at least 0.300 micrograms of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract, most preferably at least 0.400 micrograms of 2, 3-diethyl-5-methylpyrazine per gram of liquid tobacco extract. The weight ratio of (2, 3-diethyl-5-methylpyrazine) to (phenol) may be greater than 0.0200, such as greater than 0.0300, preferably greater than 0.300, more preferably greater than 0.400, most preferably greater than 0.500, such as greater than 0.600. The weight ratio of (2, 3-diethyl-5-methylpyrazine) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.0300, such as greater than 0.0400, preferably greater than 0.100, more preferably greater than 0.500, and most preferably greater than 0.0300Preferably greater than 0.800, for example greater than 0.900.

The liquid tobacco extract may comprise acetic acid. Acetic acid is an ideal compound to smooth the generated aerosol and reduce its roughness.

The liquid tobacco extract may comprise at least 300 micrograms of acetic acid per gram of liquid tobacco extract, preferably at least 500 micrograms of acetic acid per gram of liquid tobacco extract, more preferably at least 700 micrograms of acetic acid per gram of liquid tobacco extract, most preferably at least 900 micrograms of acetic acid per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 1200 micrograms of acetic acid per gram of liquid tobacco extract, more preferably at least 1500 micrograms of acetic acid per gram of liquid tobacco extract, even more preferably at least 2000 micrograms of acetic acid per gram of liquid tobacco extract, most preferably at least 2500 micrograms of acetic acid per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 3000 micrograms of acetic acid per gram of liquid tobacco extract, preferably at least 3500 micrograms of acetic acid per gram of liquid tobacco extract, more preferably at least 4000 micrograms of acetic acid per gram of liquid tobacco extract, even more preferably at least 4500 micrograms of acetic acid per gram of liquid tobacco extract, most preferably at least 5000 micrograms of acetic acid per gram of liquid tobacco extract. The weight ratio of (acetic acid) to (phenol) may be greater than 1500, for example greater than 2000, preferably greater than 2500, more preferably greater than 3000, most preferably greater than 3100, for example greater than 5000. The weight ratio of (acetic acid) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 2100, such as greater than 2800, preferably greater than 3000, more preferably greater than 4000, most preferably greater than 5500, such as greater than 7500.

The liquid tobacco extract may comprise vanillin. The liquid tobacco extract may comprise at least 3.00 x 10^-2Microgram vanillin/gram liquid tobacco extract, preferably at least 5.00X 10^-2Microgram vanillin/gram liquid tobacco extract, more preferably at least 7.00X 10^-2Microgram vanillin/gram liquid tobacco extract, most preferably at least 9.00X 10^-2Microgram vanillin per gram liquid tobacco extract. In a preferred embodiment, the liquid tobacco extractThe extract comprises at least 0.100 micrograms of vanillin per gram of liquid tobacco extract, more preferably at least 0.200 micrograms of vanillin per gram of liquid tobacco extract, even more preferably at least 0.300 micrograms of vanillin per gram of liquid tobacco extract, most preferably at least 0.400 micrograms of vanillin per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 0.500 micrograms of vanillin per gram of liquid tobacco extract, preferably at least 0.600 micrograms of vanillin per gram of liquid tobacco extract, more preferably at least 0.700 micrograms of vanillin per gram of liquid tobacco extract, even more preferably at least 0.800 micrograms of vanillin per gram of liquid tobacco extract, most preferably at least 0.900 micrograms of vanillin per gram of liquid tobacco extract. The weight ratio of (vanillin) to (phenol) may be greater than 1500, for example greater than 2000, preferably greater than 2500, more preferably greater than 3000, most preferably greater than 3100, such as greater than 5000. The weight ratio of (vanillin) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.110, such as greater than 0.150, preferably greater than 0.160, more preferably greater than 0.200, most preferably greater than 0.300, such as greater than 0.500.

The liquid tobacco extract may comprise 2-ethyl-3, 5-dimethylpyrazine. The liquid tobacco extract may comprise at least 0.0800 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, preferably at least 0.100 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, more preferably at least 0.200 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, most preferably at least 0.300 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 0.500 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, more preferably at least 0.700 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, even more preferably at least 0.900 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, most preferably at least several micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 1.10 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, preferably at least 1.30 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, more preferably at least 1.50 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, even more preferably at least 1.70 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract, most preferably at least 1.90 micrograms of 2-ethyl-3, 5-dimethylpyrazine per gram of liquid tobacco extract. The weight ratio of (2-ethyl-3, 5-dimethylpyrazine) to (phenol) may be greater than 0.100, such as greater than 0.400, preferably greater than 1.00, more preferably greater than 1.50, most preferably greater than 2.00, such as greater than 2.50. The weight ratio of (2-ethyl-3, 5-dimethylpyrazine) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.500, such as greater than 0.750, preferably greater than 1.00, more preferably greater than 2.00, most preferably greater than 3.00, such as greater than 3.50.

The liquid tobacco extract may comprise 2-methylbutyric acid. The liquid tobacco extract may comprise at least 1.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, preferably at least 2.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, more preferably at least 3.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, most preferably at least 5.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 6.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, more preferably at least 7.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, even more preferably at least 8.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, most preferably at least several micrograms of 2-methylbutyric acid per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 9.00 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, preferably at least 10.0 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, more preferably at least 12.0 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, even more preferably at least 14.0 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract, most preferably at least 15.0 micrograms of 2-methylbutyric acid per gram of liquid tobacco extract. The weight ratio of (2-methylbutyric acid) to (phenol) may be greater than 7.00, such as greater than 9.00, preferably greater than 15.0, more preferably greater than 17.0, most preferably greater than 20.0, such as greater than 21.0. The weight ratio of (2-methylbutanoic acid) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 12.0, such as greater than 17.0, preferably greater than 20.0, more preferably greater than 25.0, most preferably greater than 30.0, such as greater than 32.0.

The liquid tobacco extract may comprise 3-methylbutyric acid. The liquid tobacco extract may comprise at least 2.00 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, preferably at least 3.00 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, more preferably at least 4.00 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, most preferably at least 5.00 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 6.00 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, more preferably at least 8.00 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, even more preferably at least 10.0 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, most preferably at least a few micrograms of 3-methylbutyric acid per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 15.0 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, preferably at least 20.0 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, more preferably at least 25.0 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, even more preferably at least 30.0 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract, most preferably at least 35.0 micrograms of 3-methylbutyric acid per gram of liquid tobacco extract. The weight ratio of (3-methylbutyric acid) to (phenol) may be greater than 11.0, such as greater than 15.0, preferably greater than 20.0, more preferably greater than 30.0, most preferably greater than 50.0, such as greater than 51.0. The weight ratio of (3-methylbutanoic acid) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 18.0, such as greater than 40.0, preferably greater than 50.0, more preferably greater than 60.0, most preferably greater than 65.0, such as greater than 70.0.

The liquid tobacco extract may comprise 3-methyl-2, 4-nonanedione. The liquid tobacco extract may comprise at least 6.00 x 10^-3Microgram of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, preferably at least 8.00X 10^-3Microgram of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, more preferably at least 9.00X 10^-3Microgram of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, most preferably at least 0.0100 microgram of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 0.0300 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, more preferably at least 0.0500 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, even more preferably at least 0.0700 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, most preferably at least a few micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 0.0900 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, preferably at least 0.100 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, more preferably at least 0.150 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, even more preferably at least 0.200 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract, most preferably at least 0.250 micrograms of 3-methyl-2, 4-nonanedione per gram of liquid tobacco extract. The weight ratio of (3-methyl-2, 4-nonanedione) to (phenol) may be greater than 0.100, for example greater than 0.125, preferably greater than 0.150, more preferably greater than 0.250, most preferably greater than 0.225, for example greater than 0.250. The weight ratio of (3-methyl-2, 4-nonanedione) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.035, such as greater than 0.040, preferably greater than 0.080, more preferably greater than 0.090, most preferably greater than 0.100, such as greater than 0.130.

The liquid tobacco extract may comprise 2-methoxyphenol. The liquid tobacco extract may comprise at least 0.150 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, preferably at least 0.300 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, more preferably at least 0.500 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, most preferably at least 0.600 micrograms of 2-methoxyphenol per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 0.700 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, more preferably at least 0.800 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, even more preferably at least 0.900 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, and most preferably at least several micrograms of 2-methoxyphenol per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 1.00 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, preferably at least 1.50 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, more preferably at least 2.00 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, even more preferably at least 2.50 micrograms of 2-methoxyphenol per gram of liquid tobacco extract, and most preferably at least 3.00 micrograms of 2-methoxyphenol per gram of liquid tobacco extract. The weight ratio of (2-methoxyphenol) to (phenol) may be greater than 0.0900, such as greater than 1.00, preferably greater than 1.50, more preferably greater than 2.00, most preferably greater than 3.00, such as greater than 4.50. The weight ratio of (2-methoxyphenol) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 1.40, such as greater than, preferably greater than 1.80, more preferably greater than 2.00, most preferably greater than 3.00, such as greater than 6.00.

The liquid tobacco extract may comprise 2-phenylethanol. The liquid tobacco extract may comprise at least 1.50 micrograms of 2-phenylethanol per gram of liquid tobacco extract, preferably at least 3.00 micrograms of 2-phenylethanol per gram of liquid tobacco extract, more preferably at least 5.00 micrograms of 2-phenylethanol per gram of liquid tobacco extract, most preferably at least 7.00 micrograms of 2-phenylethanol per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 9.00 micrograms of 2-phenylethanol per gram of liquid tobacco extract, more preferably at least 10.0 micrograms of 2-phenylethanol per gram of liquid tobacco extract, even more preferably at least 11.0 micrograms of 2-phenylethanol per gram of liquid tobacco extract, most preferably at least several micrograms of 2-phenylethanol per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 13.0 micrograms of 2-phenylethanol per gram of liquid tobacco extract, preferably at least 15.0 micrograms of 2-phenylethanol per gram of liquid tobacco extract, more preferably at least 16.0 micrograms of 2-phenylethanol per gram of liquid tobacco extract, even more preferably at least 17.0 micrograms of 2-phenylethanol per gram of liquid tobacco extract, most preferably at least 18.0 micrograms of 2-phenylethanol per gram of liquid tobacco extract. The weight ratio of (2-phenylethanol) to (phenol) may be greater than 3.00, such as greater than 5.00, preferably greater than 8.00, more preferably greater than 9.00, most preferably greater than 10.0, such as greater than 25.0. The weight ratio of (2-phenylethanol) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 10.0, such as greater than 13.0, preferably greater than 14.0, more preferably greater than 15.0, most preferably greater than 17.0, such as greater than 35.0.

The liquid tobacco extract may comprise eugenol. The liquid tobacco extract may comprise at least 0.0600 micrograms of eugenol per gram of liquid tobacco extract, preferably at least 0.0650 micrograms of eugenol per gram of liquid tobacco extract, more preferably at least 0.0700 micrograms of eugenol per gram of liquid tobacco extract, most preferably at least 0.0800 micrograms of eugenol per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 0.0900 micrograms of eugenol per gram of liquid tobacco extract, more preferably at least 0.100 micrograms of eugenol per gram of liquid tobacco extract, even more preferably at least 0.200 micrograms of eugenol per gram of liquid tobacco extract, most preferably at least several micrograms of eugenol per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 0.300 micrograms of eugenol per gram of liquid tobacco extract, preferably at least 0.400 micrograms of eugenol per gram of liquid tobacco extract, more preferably at least 0.500 micrograms of eugenol per gram of liquid tobacco extract, even more preferably at least 0.600 micrograms of eugenol per gram of liquid tobacco extract, most preferably at least 0.700 micrograms of eugenol per gram of liquid tobacco extract. The weight ratio of (eugenol) to (phenol) may be greater than 0.100, such as greater than 0.0500, preferably greater than 0.150, more preferably greater than 0.250, most preferably greater than 0.300, such as greater than 1.20. The weight ratio of (eugenol) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.0200, such as greater than 0.0250, preferably greater than 0.0300, more preferably greater than 0.500, most preferably greater than 0.550, such as greater than 1.50.

The liquid tobacco extract may comprise fenugreek lactone. The liquid tobacco extract may comprise at least 3.00 x 10^-3Microgram of trigonella foenum-graecum lactone/gram of liquid tobacco extract, preferably at least 5.00 × 10^-3Microgram of trigonella foenum-graecum lactone/gram of liquid tobacco extract, more preferably at least 7.00 × 10^-3Microgram of trigonella foenum-graecum lactone per gram of liquid tobacco extract, most preferably at least 9.00 × 10^-3Microgram of fenugreek lactone per gram of liquid tobacco extract. In a preferred embodiment, the liquid tobacco extract comprises at least 0.0100 micrograms of fenugreek lactone per gram of liquid tobacco extract, more preferably at least 0.0200 micrograms of fenugreek lactone per gram of liquid tobacco extract, even more preferably at least 0.0300 micrograms of fenugreek lactone per gram of liquid tobacco extract, most preferably at least a few micrograms of fenugreek lactone per gram of liquid tobacco extract. In a particularly preferred embodiment, the liquid tobacco extract comprises at least 0.0400 micrograms of trigonella foenum-graecum lactone per gram of liquid tobacco extract, preferably at least 0.0500 micrograms of trigonella foenum-graecum lactone per gram of liquid tobacco extract, more preferably at least 0.0600 micrograms of trigonella foenum-graecum lactone per gram of liquid tobacco extract, even more preferably at least 0.0700 micrograms of trigonella foenum-graecum lactone per gram of liquid tobacco extract, most preferably at least 0.0800 micrograms of trigonella foenum-graecum lactone per gram of liquid tobacco extract. The weight ratio of (fenugreek lactone) to (phenol) may be greater than 0.0200, such as greater than 0.0400, preferably greater than 0.150, more preferably greater than 0.0450, most preferably greater than 0.0500, such as greater than 0.0510. The weight ratio of (fenugreek lactone) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600) may be greater than 0.0300, such as greater than 0.0400, preferably greater than 0.0500, more preferably greater than 0.0600, most preferably greater than 0.0700, such as greater than 0.0750.

In addition to phenol, TSNA NNK, NAT, NAB and NNN, and 2-furancarbinol, other undesirable compounds that may be present in the liquid tobacco extract but are minimized by the extraction methods described herein include formaldehyde (of carbohydrate origin) and acetaldehyde, phenolic compounds such as catechol, hydroquinone, m-cresol, o-cresol, and p-cresol, and nitrogenous compounds such as ammonia, acetamide, pyridine, 3-aminobiphenyl, 4-aminobiphenyl, and o-toluidine.

The liquid tobacco extract may comprise at most 12.0 micrograms of phenol per gram of liquid tobacco extract, for example at most 10.0 micrograms of phenol per gram of liquid tobacco extract, preferably at most 8.00 micrograms of phenol per gram of liquid tobacco extract, more preferably at most 6.00 micrograms of phenol per gram of liquid tobacco extract, even more preferably at most 4.00 micrograms of phenol per gram of liquid tobacco extract, most preferably at most 2.00 micrograms of phenol per gram of liquid tobacco extract.

The liquid tobacco extract can comprise up to 0.045 micrograms of 4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone (NNK) per gram of liquid tobacco extract, e.g., up to 0.040 micrograms of NNK per gram of liquid tobacco extract, preferably up to 0.035 micrograms of NNK per gram of liquid tobacco extract, more preferably up to 0.030 micrograms of NNK per gram of liquid tobacco extract, even more preferably up to 0.025 micrograms of NNK per gram of liquid tobacco extract, most preferably up to 0.020 micrograms of NNK per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 2.00 micrograms (R, S) -N-Nitrosoanatabine (NAT) per gram of liquid tobacco extract, e.g. at most several micrograms NAT per gram of liquid tobacco extract, preferably at most 1.50 micrograms NAT per gram of liquid tobacco extract, more preferably at most 1.00 micrograms NAT per gram of liquid tobacco extract, even more preferably at most 0.500 micrograms NAT per gram of liquid tobacco extract, most preferably at most 0.300 micrograms NAT per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 1.60 micrograms (R, S) -N-Nitrosoanabasine (NAB) per gram of liquid tobacco extract, e.g. at most micrograms NAB per gram of liquid tobacco extract, preferably at most 1.20 micrograms NAB per gram of liquid tobacco extract, more preferably at most 0.500 micrograms NAB per gram of liquid tobacco extract, even more preferably at most 0.300 micrograms NAB per gram of liquid tobacco extract, most preferably at most 0.200 micrograms NAB per gram of liquid tobacco extract.

The liquid tobacco extract can comprise up to 1.60 micrograms of N-nitrosonornicotine (NNN) per gram of liquid tobacco extract, e.g., up to several micrograms of NNN per gram of liquid tobacco extract, preferably up to 1.20 micrograms of NNN per gram of liquid tobacco extract, more preferably up to 0.500 micrograms of NNN per gram of liquid tobacco extract, even more preferably up to 0.300 micrograms of NNN per gram of liquid tobacco extract, and most preferably up to 0.200 micrograms of NNN per gram of liquid tobacco extract.

The liquid tobacco extract may comprise up to 1500 micrograms of 2-furancarbinol per gram of the liquid tobacco extract, for example up to several micrograms of 2-furancarbinol per gram of the liquid tobacco extract, preferably up to 1200 micrograms of 2-furancarbinol per gram of the liquid tobacco extract, more preferably up to 1000 micrograms of 2-furancarbinol per gram of the liquid tobacco extract, even more preferably up to 900 micrograms of 2-furancarbinol per gram of the liquid tobacco extract, most preferably up to 700 micrograms of 2-furancarbinol per gram of the liquid tobacco extract.

The liquid tobacco extract may comprise up to 60 micrograms of formaldehyde per gram of liquid tobacco extract, for example up to several micrograms of formaldehyde per gram of liquid tobacco extract, preferably up to 50 micrograms of formaldehyde per gram of liquid tobacco extract, more preferably up to 40 micrograms of formaldehyde per gram of liquid tobacco extract, even more preferably up to 30 micrograms of formaldehyde per gram of liquid tobacco extract, most preferably up to 20 micrograms of formaldehyde per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 60 micrograms of acetaldehyde per gram of the liquid tobacco extract, for example at most 55 micrograms of acetaldehyde per gram of the liquid tobacco extract, more preferably at most 45 micrograms of acetaldehyde per gram of the liquid tobacco extract, even more preferably at most 35 micrograms of acetaldehyde per gram of the liquid tobacco extract, most preferably at most 30 micrograms of acetaldehyde per gram of the liquid tobacco extract.

The liquid tobacco extract may comprise at most 5.00 micrograms of catechol per gram of liquid tobacco extract, such as at most several micrograms of catechol per gram of liquid tobacco extract, preferably at most 4.00 micrograms of catechol per gram of liquid tobacco extract, more preferably at most 3.00 micrograms of catechol per gram of liquid tobacco extract, even more preferably at most 2.00 micrograms of catechol per gram of liquid tobacco extract, most preferably at most 1.00 micrograms of catechol per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 1.00 micrograms of hydroquinone per gram of liquid tobacco extract, for example at most 0.950 micrograms of hydroquinone per gram of liquid tobacco extract, preferably at most 0.900 micrograms of hydroquinone per gram of liquid tobacco extract, more preferably at most 0.850 micrograms of hydroquinone per gram of liquid tobacco extract, even more preferably at most 0.800 micrograms of hydroquinone per gram of liquid tobacco extract, most preferably at most 0.700 micrograms of hydroquinone per gram of liquid tobacco extract.

The liquid tobacco extract may comprise up to 1.30 micrograms of m-cresol per gram of liquid tobacco extract, for example up to 1.20 micrograms of m-cresol per gram of liquid tobacco extract, preferably up to 1.00 micrograms of m-cresol per gram of liquid tobacco extract, more preferably up to 0.800 micrograms of m-cresol per gram of liquid tobacco extract, even more preferably up to 0.600 micrograms of m-cresol per gram of liquid tobacco extract, most preferably up to 0.500 micrograms of m-cresol per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 1.60 micrograms of o-cresol per gram of liquid tobacco extract, for example at most 1.30 micrograms of o-cresol per gram of liquid tobacco extract, preferably at most 1.10 micrograms of o-cresol per gram of liquid tobacco extract, more preferably at most 0.800 micrograms of o-cresol per gram of liquid tobacco extract, even more preferably at most 0.600 micrograms of o-cresol per gram of liquid tobacco extract, most preferably at most 0.400 micrograms of o-cresol per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 2.10 micrograms of p-cresol per gram of liquid tobacco extract, for example at most 1.50 micrograms of p-cresol per gram of liquid tobacco extract, preferably at most 1.20 micrograms of p-cresol per gram of liquid tobacco extract, more preferably at most 1.00 micrograms of p-cresol per gram of liquid tobacco extract, even more preferably at most 0.900 micrograms of p-cresol per gram of liquid tobacco extract, most preferably at most 0.700 micrograms of p-cresol per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 350 micrograms of ammonia per gram of liquid tobacco extract, for example at most 300 micrograms of ammonia per gram of liquid tobacco extract, preferably at most 275 micrograms of ammonia per gram of liquid tobacco extract, more preferably at most 250 micrograms of ammonia per gram of liquid tobacco extract, even more preferably at most 200 micrograms of ammonia per gram of liquid tobacco extract, most preferably at most 175 micrograms of ammonia per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 250 micrograms of acetamide per gram of liquid tobacco extract, for example at most 225 micrograms of acetamide per gram of liquid tobacco extract, preferably at most 200 micrograms of acetamide per gram of liquid tobacco extract, more preferably at most 150 micrograms of acetamide per gram of liquid tobacco extract, even more preferably at most 100 micrograms of acetamide per gram of liquid tobacco extract, most preferably at most 70 micrograms of acetamide per gram of liquid tobacco extract.

The liquid tobacco extract may comprise at most 45 micrograms of pyridine per gram of liquid tobacco extract, for example at most 35 micrograms of pyridine per gram of liquid tobacco extract, preferably at most 25 micrograms of pyridine per gram of liquid tobacco extract, more preferably at most 20 micrograms of pyridine per gram of liquid tobacco extract, even more preferably at most 15 micrograms of pyridine per gram of liquid tobacco extract, most preferably at most 10 micrograms of pyridine per gram of liquid tobacco extract.

The liquid tobacco extract can be used to form a nicotine composition. The liquid tobacco extract can be further processed to form a nicotine composition. The liquid tobacco extract can be concentrated in a drying step to form a concentrated tobacco extract. The concentrated tobacco extract can be used to form a nicotine composition. One such concentrated tobacco extract typically contains less than about 20% by weight water. Preferably, the concentrated tobacco extract comprises from 8 wt% to 15 wt% water, based on the weight of the concentrated tobacco extract.

The concentrated tobacco extract may have a non-aqueous extraction solvent content of about 65% to about 95% by weight, preferably about 65% to 85% by weight, most preferably about 75% to about 85% by weight. The non-aqueous extraction solvent is preferably triacetin, glycerol, propylene glycol, 1, 3-propanediol, or a mixture thereof.

The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of additional nicotine. The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of an additional non-aqueous solvent. The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of additional water. The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of additional flavorants.

In an exemplary embodiment, the liquid tobacco extract is a concentrated tobacco extract comprising 84% by weight propylene glycol, 12.5% by weight water, 1.2% by weight nicotine, 0.5% by weight acetic acid, and the balance 1.8% by weight other components, including desirable flavorant compounds derived from the extraction process described herein.

According to the present disclosure, there is also provided a cartridge comprising a nicotine composition, wherein the nicotine composition comprises a liquid tobacco extract or a concentrated tobacco extract as described herein.

The nicotine composition may be a liquid nicotine composition or a gel nicotine composition.

The nicotine composition may be used in an aerosol-generating system. In such aerosol-generating systems, the nicotine composition is typically heated within the aerosol-generating device.

As used herein, the term "aerosol-generating device" refers to a device comprising a heater element that interacts with a nicotine composition of the invention to produce an aerosol. During use, the volatile compound is released from the nicotine composition by heat transfer and entrained in air drawn through the aerosol-generating device. As the released compound cools, the compound condenses to form an aerosol that is inhaled by the consumer.

Upon heating the nicotine composition, an aerosol containing volatile compounds collected from the tobacco starting material in the extraction process is released.

The nicotine composition comprises a liquid tobacco extract or a concentrated tobacco extract as described herein.

The nicotine composition may comprise at least about 10% by weight of the liquid tobacco extract. Preferably, the nicotine composition comprises at least about 20% by weight of the liquid tobacco extract. More preferably, the nicotine composition comprises at least about 30% by weight of the liquid tobacco extract. In a preferred embodiment, the nicotine composition comprises at least about 40% by weight liquid tobacco extract, more preferably at least about 50% by weight liquid tobacco extract, even more preferably at least about 60% by weight liquid tobacco extract. In a particularly preferred embodiment, the nicotine composition comprises at least about 65% by weight liquid tobacco extract, more preferably at least about 70% by weight liquid tobacco extract, even more preferably at least about 75% by weight liquid tobacco extract, and most preferably at least about 80% by weight liquid tobacco extract.

In some embodiments, the nicotine composition can comprise a liquid tobacco extract that is a concentrated tobacco extract. The nicotine composition may comprise at least about 10% by weight of the concentrated tobacco extract. Preferably, the nicotine composition comprises at least about 20% by weight of the concentrated tobacco extract. More preferably, the nicotine composition comprises at least about 30% by weight of the concentrated tobacco extract. In a preferred embodiment, the nicotine composition comprises at least about 40% by weight of the concentrated tobacco extract, more preferably at least about 50% by weight of the concentrated tobacco extract, and even more preferably at least about 60% by weight of the concentrated tobacco extract. In a particularly preferred embodiment, the nicotine composition comprises at least about 65% by weight of the concentrated tobacco extract, more preferably at least about 70% by weight of the concentrated tobacco extract, even more preferably at least about 75% by weight of the concentrated tobacco extract, and most preferably at least about 80% by weight of the concentrated tobacco extract.

In some embodiments, the nicotine composition comprises from about 40% to about 95% by weight of the liquid tobacco extract. More preferably, the nicotine composition comprises from about 40% to about 95% by weight of the liquid tobacco extract. Even more preferably, the nicotine composition comprises from about 50% to about 95% by weight of the liquid tobacco extract. Most preferably, the nicotine composition comprises from about 60% to about 95% by weight of the liquid tobacco extract. In some particularly preferred embodiments, the nicotine composition comprises from about 70% to about 95% by weight liquid tobacco extract, even more preferably from about 80% to about 95% by weight liquid tobacco extract. The liquid tobacco extract may be a concentrated tobacco extract.

In some embodiments, the nicotine composition comprises from about 40% to about 90% by weight of the liquid tobacco extract. More preferably, the nicotine composition comprises from about 40% to about 90% by weight of the liquid tobacco extract. Even more preferably, the nicotine composition comprises from about 50% to about 90% by weight of the liquid tobacco extract. Most preferably, the nicotine composition comprises from about 60% to about 90% by weight of the liquid tobacco extract. In some particularly preferred embodiments, the nicotine composition comprises from about 70% to about 90% by weight liquid tobacco extract, even more preferably from about 80% to about 90% by weight liquid tobacco extract. The liquid tobacco extract may be a concentrated tobacco extract.

In some embodiments, the nicotine composition comprises from about 40% to about 85% by weight of the liquid tobacco extract. More preferably, the nicotine composition comprises from about 40% to about 85% by weight of the liquid tobacco extract. Even more preferably, the nicotine composition comprises from about 85% to about 90% by weight of the liquid tobacco extract. Most preferably, the nicotine composition comprises from about 60% to about 85% by weight of the liquid tobacco extract. In some particularly preferred embodiments, the nicotine composition comprises from about 70% to about 85% by weight liquid tobacco extract, even more preferably from about 80% to about 85% by weight liquid tobacco extract. The liquid tobacco extract may be a concentrated tobacco extract.

The nicotine composition may comprise up to about 100% by weight of the liquid tobacco extract. In some embodiments, the nicotine composition can be formed directly from a liquid tobacco extract without the addition of additional non-aqueous solvents, flavorants, or nicotine. That is, the nicotine composition may comprise 100% by weight of the liquid tobacco extract. In some embodiments, the liquid tobacco extract is a concentrated tobacco extract such that the nicotine composition can comprise 100% by weight of the concentrated tobacco extract. In embodiments where the nicotine composition comprises 100% by weight of the liquid tobacco extract or 100% by weight of the concentrated tobacco extract, no additional non-aqueous solvent is present.

Alternatively, in some embodiments, the nicotine composition comprising a liquid tobacco extract may comprise an additional non-aqueous solvent. The additional non-aqueous solvent is a non-aqueous solvent added after the extraction step. The additional non-aqueous solvent is a solvent that supplements the non-aqueous extraction solvent present in the liquid tobacco extract. In embodiments where the liquid tobacco extract is a concentrated tobacco extract, the nicotine composition comprising the concentrated tobacco extract may comprise an additional non-aqueous solvent. The total content of non-aqueous solvent in the nicotine composition includes the non-aqueous extraction solvent and additional non-aqueous solvent, if present.

The additional non-aqueous solvent may be an aerosol former. Preferably, the additional non-aqueous solvent is triacetin, glycerol, propylene glycol, 1, 3-propanediol, or a mixture thereof.

In embodiments where the nicotine composition comprises an additional non-aqueous solvent, the nicotine composition may comprise 90% by weight or less of the additional non-aqueous solvent. Preferably, the nicotine composition comprises 80 wt% or less of additional non-aqueous solvent. More preferably, the nicotine composition comprises 70 wt% or less of additional non-aqueous solvent. In a preferred embodiment, the nicotine composition comprises about 60% by weight or less of the additional non-aqueous solvent, more preferably about 50% by weight or less of the additional non-aqueous solvent, and even more preferably about 40% by weight or less of the additional non-aqueous solvent. In particularly preferred embodiments, the nicotine composition comprises about 35% by weight or less of the additional non-aqueous solvent, more preferably about 30% by weight or less of the additional non-aqueous solvent, even more preferably about 25% by weight or less of the additional non-aqueous solvent, and most preferably about 20% by weight or less of the liquid tobacco extract.

For example, the nicotine composition may comprise 80 wt.% of the concentrated tobacco extract and 20 wt.% of the additional non-aqueous solvent. In this embodiment, the nicotine composition comprises 20 wt% glycerin as an additional non-aqueous solvent and 80 wt% of a concentrated tobacco extract comprising 84 wt% propylene glycol, 12.5 wt% water, 1.2 wt% nicotine, 0.5 wt% total acetic acid and the balance 1.8 wt% other components, including desired flavor compounds derived from the extraction process described herein. Thus, the nicotine composition of this exemplary embodiment comprises 20 wt.% glycerin, 67.2 wt.% propylene glycol, 10 wt.% water, 0.96 wt.% nicotine, 0.4 wt.% total acetic acid, and the balance 1.44 wt.% other components, including the desired flavor compounds derived from the extraction process described herein. The composition comprises a total content of 87.2 wt% of non-aqueous solvents comprising glycerol and propylene glycol.

Additional nicotine, water, non-aqueous solvents, and flavor compounds can be added to the liquid tobacco extract or the concentrated tobacco extract to form a nicotine composition.

Additional nicotine may be added to the liquid tobacco extract to form a nicotine composition. At least 50% by weight of the nicotine content in the nicotine composition based on the total weight of the nicotine composition may be from a liquid tobacco extract, rather than being added after extraction. Preferably, at least 80% by weight of the nicotine content in the nicotine composition is from the liquid tobacco extract, based on the total weight of the nicotine composition, rather than being added after extraction. More preferably, at least 90% by weight of the nicotine content in the nicotine composition is from the liquid tobacco extract, based on the total weight of the nicotine composition, rather than being added after extraction. Even more preferably, the nicotine content in the nicotine composition of 100 wt. -% based on the total weight of the nicotine composition is derived from a liquid tobacco extract, rather than being added after extraction.

Additional non-aqueous solvents can be added to the liquid tobacco extract to form the nicotine composition. At least 50 wt% of the non-aqueous extraction solvent component of the nicotine composition based on the total weight of the nicotine composition may be from a liquid tobacco extract, rather than being added after extraction. Preferably, at least 80 wt% of the non-aqueous extraction solvent component in the nicotine composition is from the liquid tobacco extract, based on the total weight of the nicotine composition, rather than being added after extraction. Even more preferably, at least 90 wt% of the non-aqueous extraction solvent component in the nicotine composition is from the liquid tobacco extract, based on the total weight of the nicotine composition, rather than being added after extraction.

Additional water may be added to the liquid tobacco extract to form the nicotine composition. At least 50 wt% of the water content in the nicotine composition based on the total weight of the nicotine composition may be from the liquid tobacco extract, rather than being added after extraction. Preferably, at least 80 wt% of the water content in the nicotine composition is from the liquid tobacco extract, based on the total weight of the nicotine composition, rather than being added after extraction. Even more preferably, at least 90% by weight of the water content in the nicotine composition based on the total weight of the nicotine composition is from the liquid tobacco extract, rather than being added after extraction.

Additional flavor compounds can be added to the liquid tobacco extract to form a nicotine composition. At least 50% by weight of the desired tobacco flavor content in the nicotine composition based on the total weight of the nicotine composition can be from the liquid tobacco extract, rather than added after extraction. Preferably, at least 80% by weight of the desired tobacco flavor content in the nicotine composition based on the total weight of the nicotine composition is from the liquid tobacco extract, rather than being added after extraction. More preferably, at least 90% by weight of the desired tobacco flavor content in the nicotine composition based on the total weight of the nicotine composition is from the liquid tobacco extract, rather than being added after extraction. Even more preferably, 100% by weight of the desired tobacco flavor in the nicotine composition based on the total weight of the nicotine composition is from the liquid tobacco extract, rather than being added after extraction.

For example, at least 50 wt% of the beta-ionone content in the nicotine composition based on the total weight of the nicotine composition may be from a tobacco extract, rather than being added after extraction. Preferably, at least 80 wt% of the beta-ionone content in the nicotine composition based on the total weight of the nicotine composition is from a tobacco extract, rather than being added after extraction. More preferably, at least 90 wt% of the beta-ionone content in the nicotine composition based on the total weight of the nicotine composition is from the tobacco extract, rather than being added after extraction. Even more preferably, 100 wt% of the beta-ionone content in the nicotine composition based on the total weight of the nicotine composition is from a tobacco extract, rather than being added after extraction.

As another example, at least 50 wt% of the beta-damascenone content in the nicotine composition based on the total weight of the nicotine composition may be from a tobacco extract, rather than being added after extraction. Preferably, at least 80 wt% of the beta-damascenone content in the nicotine composition based on the total weight of the nicotine composition is from a tobacco extract, rather than being added after extraction. More preferably, at least 90 wt% of the beta-damascenone content in the nicotine composition based on the total weight of the nicotine composition is from a tobacco extract, rather than being added after extraction. Even more preferably, the content of beta-damascenone in the nicotine composition is 100 wt. -% based on the total weight of the nicotine composition, originating from the tobacco extract, rather than being added after the extraction.

In some embodiments, the nicotine composition may comprise one or more water-soluble organic acids. As used herein with reference to the present invention, the term "water-soluble organic acid" describes an organic acid having a water solubility greater than or equal to about 500mg/ml at 20 ℃.

One or more water-soluble organic acids may advantageously bind nicotine in the liquid tobacco extract by forming one or more nicotine salts. The one or more nicotine salts may advantageously be dissolved and stabilized in water or a non-aqueous solvent present in the liquid tobacco extract. This may advantageously reduce nicotine adsorption in the upper respiratory tract and enhance pulmonary nicotine delivery and retention.

More preferably, the nicotine composition comprises one or more water-soluble carboxylic acids. Suitable water-soluble carboxylic acids include, but are not limited to, acetic acid, citric acid, lactic acid, levulinic acid, malic acid, malonic acid, and pyruvic acid. Most preferably, the nicotine composition comprises lactic acid.

Preferably, the nicotine composition has a water soluble organic acid content of greater than or equal to about 2% by weight. More preferably, the nicotine composition has a water soluble organic acid content of greater than or equal to about 3% by weight.

The water-soluble organic acid may be acetic acid. Acetic acid derived from the extraction process may be present in the nicotine composition, or acetic acid may be added after the extraction process. The additional acetic acid is acetic acid added after the extraction process.

If acetic acid is added to the liquid tobacco extract to form the nicotine composition, the total content of acetic acid in the nicotine composition, including acetic acid and additional acetic acid derived from the extraction process, is preferably from about 0.01 wt.% to about 8 wt.%, such as from about 0.03 wt.% to about 8 wt.%, from about 0.3 wt.% to about 8 wt.%, from about 2 wt.% to about 8 wt.%, or from about 3 wt.% to about 8 wt.%. More preferably, the total acetic acid content is from about 0.01 wt% to about 6 wt%, such as from about 0.03 wt% to about 6 wt%, from about 0.3 wt% to about 6 wt%, from about 2 wt% to about 6 wt%, or from about 3 wt% to about 6 wt%.

Preferably, the nicotine composition has a water soluble organic acid content of less than or equal to about 8% by weight. More preferably, the nicotine composition has a water soluble organic acid content of less than or equal to about 6% by weight.

Preferably, the nicotine composition has a water soluble organic acid content of about 2% to about 8% by weight. For example, the nicotine composition may have a water soluble organic acid content of about 2% to about 6% by weight.

More preferably, the nicotine composition has a water soluble organic acid content of about 3% to about 8% by weight. For example, the nicotine composition may have a water soluble organic acid content of about 3% to about 6% by weight.

The nicotine composition may comprise one or more non-tobacco derived flavors, which may be added to the liquid tobacco extract during formation of the nicotine composition. Suitable non-tobacco derived flavorants include, but are not limited to, menthol.

Preferably, the nicotine composition has a non-tobacco derived flavor content of less than or equal to about 4% by weight. More preferably, the nicotine composition has a non-tobacco derived flavor content of less than or equal to about 3% by weight.

The nicotine composition may comprise a non-aqueous solvent, water, nicotine, and a flavor compound, as previously described herein.

The nicotine composition may comprise a total content of about 10 wt% to about 95 wt% of the non-aqueous solvent. The nicotine composition preferably comprises a total content of non-aqueous solvent from about 50% to about 95% by weight, such as from about 65% to about 95% by weight, more preferably from about 70% to about 90% by weight, most preferably from about 80% to about 90% by weight. The non-aqueous solvent is preferably triacetin, glycerol, propylene glycol, 1, 3-propanediol, or a mixture thereof.

The nicotine composition may comprise propylene glycol in a total content of about 10% to about 95% by weight. The nicotine composition may comprise propylene glycol in a total content of from about 20 wt% to about 95 wt%, for example from about 50 wt% to about 95 wt%, or from about 65 wt% to about 95 wt%, from about 70 wt% to about 90 wt%, or from about 80 wt% to about 90 wt%.

The nicotine composition may comprise triacetin in a total content of about 10% to about 95% by weight. The nicotine composition may comprise triacetin in a total content of from about 20% to about 95% by weight, for example from about 50% to about 95%, from about 70% to about 90% or from about 65% to about 95%, or from about 80% to about 90%.

The nicotine composition may comprise glycerin in a total content of about 10 wt% to about 95 wt%. The nicotine composition may comprise glycerin in a total content of about 20 wt% to about 95 wt%, for example about 50 wt% to about 95 wt%, or about 65 wt% to about 95 wt%, about 70 wt% to about 90 wt%, or about 80 wt% to about 90 wt%.

The nicotine composition may comprise 1, 3-propanediol in a total content of about 10% to about 95% by weight. The nicotine composition may comprise 1, 3-propanediol in a total content of from about 20 wt% to about 95 wt%, for example from about 50 wt% to about 95 wt%, or from about 65 wt% to about 95 wt%, or from about 80 wt% to about 90 wt%.

The nicotine composition of the present invention comprises at least 0.2% by weight nicotine. More preferably, the nicotine content of the nicotine composition is at least about 0.4% by weight. The nicotine content of the nicotine composition can be about 12% by weight or less, for example about 10% by weight or less, preferably about 8% by weight or less, more preferably about 5% by weight or less, preferably about 3.6% by weight or less. Most preferably, the nicotine composition comprises from about 0.4% to 3.6% by weight nicotine based on the weight of the nicotine composition.

The nicotine composition may comprise 1 to 85% by weight of water. The nicotine composition may comprise from 2 wt% to 50 wt% water. The nicotine composition may comprise 3 to 30 wt% water. The nicotine composition may comprise 5 to 25 wt% water. The nicotine composition may comprise 8 to 20 wt% water. The nicotine composition preferably comprises 10 to 15 wt% water.

The nicotine composition may be a gel nicotine composition. Since nicotine may be irritating to the skin, it is desirable to prevent any possible nicotine leakage by locking the nicotine in the gel at room temperature. Such gels are described, for example, in WO 2018/019543a 1.

Advantageously, the gel nicotine composition comprises a thermoreversible gel. This means that the gel becomes fluid when heated to the melting temperature and becomes gel again at the gelling temperature. Preferably, the gelation temperature is at or above room temperature and atmospheric pressure. Atmospheric pressure means 1 atmosphere. Preferably, the melting temperature is higher than the gelling temperature. Preferably, the melting temperature of the gel is higher than 50 degrees celsius or 60 degrees celsius or 70 degrees celsius, and more preferably higher than 80 degrees celsius. Melting temperature in this context means the temperature at which the gel is no longer a solid and begins to flow.

The gel nicotine composition may comprise a suitable gelling agent. Preferably, the gelled nicotine composition comprises agar, agarose, sodium alginate or gellan gum. Most preferably, the gel nicotine composition comprises agar. The gel nicotine composition preferably comprises from about 0.5% to about 5% by weight of the gelling agent, more preferably from about 0.8% to about 1% by weight of the gelling agent.

The gel nicotine composition includes a liquid tobacco extract. Preferably, the gel nicotine composition comprises from about 50% to about 99.5% liquid tobacco extract, more preferably from about 60% to about 99.5% liquid tobacco extract, even more preferably from about 70% to about 99.5% liquid tobacco extract, most preferably from about 80% to about 99.5% liquid tobacco extract.

The liquid tobacco extract can be a concentrated tobacco extract such that the gel nicotine composition can comprise a concentrated tobacco extract. Preferably, the gel nicotine composition comprises from about 50% to about 99.5% of the concentrated tobacco extract, more preferably from about 60% to about 99.5% of the concentrated tobacco extract, even more preferably from about 70% to about 99.5% of the concentrated tobacco extract, and most preferably from about 80% to about 99.5% of the concentrated tobacco extract.

The gel nicotine composition may comprise an additional non-aqueous solvent. Preferably, the gel nicotine composition comprises from about 5% to 49.5%, more preferably from about 10% to about 40%, even more preferably from about 15% to about 30%, most preferably from about 20% to about 30% of an additional non-aqueous solvent. The additional non-aqueous solvent is preferably glycerol, propylene glycol, triacetin, 1, 3-propanediol, or a mixture thereof.

The total content of non-aqueous solvent in the gel nicotine composition includes the non-aqueous extraction solvent and additional non-aqueous solvent (if present). The gel nicotine composition may include a total content of about 10% to about 95% by weight of the non-aqueous solvent. The gel nicotine composition preferably comprises a total content of non-aqueous solvent from about 50% to about 95% by weight, such as from about 65% to about 95% by weight, more preferably from about 70 to about 90% by weight, most preferably from about 80% to about 90% by weight. The non-aqueous solvent is preferably triacetin, glycerol, propylene glycol, 1, 3-propanediol, or a mixture thereof.

The gel nicotine composition may comprise 1 wt% to 85 wt% water. The gel nicotine composition may comprise from 2 wt% to 50 wt% water. The gel nicotine composition may preferably comprise 3 to 30 wt% water. The gel nicotine composition may comprise 8 wt% to 20 wt% water. The gel nicotine composition may comprise 10 wt% to 15 wt% water.

The gel nicotine composition comprises at least 0.2 wt% nicotine. More preferably, the nicotine content in the gel nicotine composition is at least about 0.4% by weight. The gel nicotine composition may have a nicotine content of about 12% by weight or less, for example about 10% by weight or less, preferably about 8% by weight or less, more preferably about 5% by weight or less, preferably about 3.6% by weight or less. Most preferably, the gel nicotine composition comprises about 0.4% to 3.6% nicotine by weight.

In an exemplary embodiment, the gel nicotine composition comprises 80% by weight of liquid tobacco extract, 19% by weight of additional non-aqueous solvent, and 1% agar. In this exemplary embodiment, the nicotine composition comprises 19 wt% glycerin as an additional non-aqueous solvent and 80 wt% of a liquid tobacco extract comprising 59 wt% glycerin, 37.5 wt% water, 1.2 wt% nicotine, 0.5 wt% total acetic acid, and the balance 1.8 wt% other components, including desired flavor compounds derived from the extraction process described herein. Thus, the nicotine composition of this exemplary embodiment comprises 66.2 wt.% glycerin, 30 wt.% water, 0.96 wt.% nicotine, 0.4 wt.% total acetic acid, 1% agar, and the balance 1.44 wt.% other components, including the desired flavor compounds derived from the extraction process described herein.

A nicotine composition comprising a liquid tobacco extract may be provided in a cartridge for an aerosol-generating system. The cartridge may include a nebulizer configured to generate an aerosol from the nicotine composition. The nebulizer may be a thermal nebulizer configured to heat the nicotine composition to generate an aerosol. The thermal atomizer may include, for example, a heater and a liquid delivery element configured to deliver the nicotine composition to the heater. The liquid transport element may comprise a capillary wick. Alternatively, the nebulizer may be a non-thermal nebulizer configured to generate an aerosol from the nicotine composition by means other than heating. The non-thermal atomizer may be, for example, an impinging jet atomizer, an ultrasonic atomizer, or a vibrating mesh atomizer.

The cartridge comprising the nicotine composition may be used in conjunction with any suitable aerosol-generating device comprising a housing configured to receive at least a portion of the cartridge. The aerosol-generating device may comprise a battery and control electronics.

The nicotine composition may be a gel nicotine composition or a liquid nicotine composition for use in an aerosol-generating system as described herein.

By controlling the parameters of the extraction process, the characteristics of the liquid tobacco extract and the resulting aerosol produced from the nicotine composition and delivered to the consumer can be adjusted.

According to the present invention, there is provided a liquid tobacco extract comprising a non-aqueous solvent, nicotine, and a weight ratio of (β -ionone + β -damascone) to (phenol) of greater than 0.25, prepared by a process comprising the steps of: heating the tobacco starting material at an extraction temperature of between 100 ℃ and 160 ℃ for at least 90 minutes; collecting volatile compounds released from the tobacco starting material during the heating step; and forming a liquid tobacco extract comprising the collected volatile compounds.

As described above, the liquid tobacco extract may be produced from a tobacco starting material consisting of a single type of natural tobacco. The tobacco starting material may comprise a blend of two or more types of natural tobacco. Alternatively, the liquid tobacco extract may be produced from a blend produced from a first tobacco starting material consisting of a first single type of natural tobacco extracted to form a first extract and a second tobacco starting material consisting of a second single type of natural tobacco extracted to form a second extract, wherein the first extract and the second extract are blended to form the liquid tobacco extract. Two or more extracts may be blended in this manner to form a liquid tobacco extract. The ratio of the different tobacco types may be adjusted according to the desired aerosol characteristics. For example, the proportion of burley tobacco may be increased when it is desired to provide relatively high levels of nicotine.

The term "natural tobacco" as used herein in the present invention describes any part of any plant member of the genus nicotiana, including, but not limited to, leaf, midrib, stem, and stalk. In particular, natural tobacco may include smoky tobacco material, burley tobacco material, oriental tobacco material, maryland tobacco material, dark flue-cured tobacco material, daylily tobacco material, as well as materials from other rare or specialty tobaccos, or mixtures thereof. As will be described in greater detail below, the tobacco material may be whole (e.g., whole tobacco leaves), shredded, cut, or ground.

In the case where it is desired to produce a liquid tobacco extract from a combination of two or more different tobacco types, to form the liquid tobacco extract, the tobacco types may be heated individually at different extraction temperatures within a defined range of 100 degrees celsius to 160 degrees celsius, or a mixture of tobacco types may be heated together at a single extraction temperature within that range.

The tobacco starting material may be a solid tobacco material, such as a powder, a leaf chip or a shred or a whole leaf. Alternatively, the tobacco starting material may be a liquid tobacco material, such as a briquette, gel, slurry or suspension.

The tobacco starting material may be derived from any suitable tobacco material, including, but not limited to, tobacco leaf, tobacco stem, reconstituted tobacco, cast tobacco, extruded tobacco, or tobacco-derived pellets.

Preferably, in the step of preparing the tobacco starting material, the tobacco is ground or cut to reduce the size of the tobacco particles in the tobacco starting material. This may advantageously improve the heating uniformity and extraction efficiency of the tobacco starting material.

The tobacco starting material may optionally be dried prior to the heating step to reduce the water content of the tobacco starting material. Drying of the tobacco starting material may be carried out by any suitable chemical or physical drying process. Alternatively, water may be added to the tobacco starting material prior to the heating step to increase the water content of the tobacco starting material.

The step of preparing the tobacco starting material may comprise the step of impregnating the tobacco starting material with an aerosol-forming agent. When such impregnation of the tobacco starting material is performed prior to the heating step, it may be advantageous to increase the amount of certain desired tobacco compounds which are released from the tobacco starting material upon heating. For example, it has been found that impregnating a tobacco starting material with glycerine advantageously increases the amount of nicotine extracted from the tobacco starting material. In another example, it has been found that impregnating a tobacco starting material with a non-aqueous extraction solvent, such as propylene glycol, glycerin, 1, 3-propanediol, triacetin, or mixtures thereof, which is also an aerosol former, advantageously increases the amount of flavor compounds extracted from the tobacco starting material.

Preferably, in the step of preparing the natural tobacco material, the tobacco is not subjected to any treatment suitable for altering the pH of the tobacco. In particular, in the step of preparing the natural tobacco material, the tobacco is not subjected to any treatment suitable for significantly increasing the pH of the tobacco. For example, the natural tobacco material is not contacted with an aqueous solution containing a salt of an alkali metal or alkaline earth metal. Advantageously, it has been found that maintaining the tobacco material in a less modified state can provide a more authentic or natural flavor profile that can be perceived by the consumer. Furthermore, the present inventors have found that subjecting the natural tobacco material to a treatment suitable for increasing the pH of the tobacco, such as an alkaline treatment, prior to heating the tobacco material as part of the extraction process, results in lower levels of the desired heated tobacco flavor compounds in the liquid tobacco extract. For example, it was found that not subjecting a natural tobacco material to an alkaline treatment was associated with a significant increase in the weight ratio of (beta-ionone + beta-damascone) to (phenol) in the liquid tobacco extract compared to an equivalent alkaline-treated natural tobacco material.

In a preferred embodiment, the tobacco starting material consists of natural tobacco. Thus, the water content in the tobacco starting material may be about 11% by weight (the water content typically present in natural tobacco materials).

In other embodiments, the tobacco starting material may comprise one or more additional ingredients, such as a non-aqueous solvent or added water or both. An example of a suitable solvent is propylene glycol.

Thus, the tobacco starting material may comprise at least about 40% by weight of natural tobacco material or at least about 60% by weight of natural tobacco material or at least about 80% by weight of natural tobacco material or at least about 90% by weight of natural tobacco material or at least about 95% by weight of natural tobacco material.

In some embodiments, the water content in the tobacco starting material can be from about 3% to about 60% by weight, more preferably from about 3% to about 20% by weight, and even more preferably from about 3% to about 12% by weight. In other embodiments, the water content in the tobacco starting material can be from about 5% to about 60% by weight, more preferably from about 5% to about 20% by weight, and even more preferably from about 5% to about 12% by weight. In further embodiments, the water content in the tobacco starting material can be from about 8% to about 60% by weight, more preferably from about 8% to about 20% by weight, and even more preferably from about 8% to about 12% by weight.

In some embodiments, the non-aqueous solvent content may be at least about 5 wt.%, or at least about 10 wt.%, or at least about 15 wt.%, or at least about 20 wt.%, or at least about 25 wt.%, or at least about 30 wt.%, or at least about 35 wt.%, or at least about 40 wt.%.

Optionally, the tobacco starting material may be digested with enzymes prior to the heating step. This has been found to provide a significant increase in the yield of certain flavour compounds from tobacco starting materials.

Prior to the heating step, the tobacco starting material can optionally be analyzed to determine composition, e.g., reducing sugar content of the alkaloid. This information about the composition can be helpful for selecting an appropriate extraction temperature.

The extraction temperature and heating duration may be selected within ranges defined by factors such as the type of tobacco, possible other components of the tobacco starting material, the desired nicotine level, or the desired composition of the nicotine composition formed from the liquid tobacco extract. By controlling the combination of extraction temperature and time, the liquid tobacco extract can be adjusted according to the desired characteristics of the aerosol produced by the nicotine composition. In particular, the ratio of specific tobacco compounds can be adjusted to a degree by selecting extraction parameters so as to maximize the ratio of desired tobacco compounds to undesired tobacco compounds within the liquid tobacco extract and any resulting nicotine composition formed from the liquid tobacco extract.

For a particular tobacco compound, the level of compound release during the extraction process as a function of extraction temperature can be readily determined for any given tobacco starting material. For example, it has been found that the level of nicotine released from the tobacco starting material will generally increase with increasing extraction temperature. It has been found that the rate of increase is different for different tobacco types.

It has also been found that the content of desirable tobacco flavour compounds, such as beta-damascenone and beta-ionone, released from tobacco material will increase with increasing extraction temperature up to a certain peak extraction temperature, after which the content will start to decrease. The peak extraction temperature of such flavour compounds is typically in the range of 100 to 160 degrees celsius, so that the level of desired flavour compounds can be effectively optimised in the extraction process.

In processes in which tobacco material is soaked in a suitable liquid solvent, such as an aerosol former, at or below room temperature for several weeks to extract tobacco components into the solvent, a much lower content of components than that of the composition of the invention is typically obtained. Extraction processes in which tobacco material is soaked in a suitable solvent, such as an aerosol former, at or below room temperature do not produce compounds that are not present in tobacco but are generated thermally after the maillard reaction has occurred. One such compound produced by heating after a Maillard reaction (Maillard reaction) has occurred is furanone. Furanones are derived from the heat treatment of the inherent reducing sugar content of tobacco plant material with other tobacco plant components.

Flue-cured tobacco typically has a much higher reducing sugar content (up to 25% by weight) than burley tobacco, and the amount of furanones released when the flue-cured tobacco is heated is found to vary significantly depending on the extraction temperature, with a direct correlation between the extraction temperature and the level of furanones released. As described herein, the peak extraction temperature of such flavor compounds is typically in the range of 100 to 160 degrees celsius, such that the levels of desired flavor compounds can be effectively optimized in the extraction process.

It has been found that many undesirable tobacco compounds slowly increase as the extraction temperature rises to a threshold temperature above which a rapid increase is observed. This applies for example to the levels of phenol, other phenolic compounds and TSNA, and in the case of flue-cured tobacco, to the levels of furan and formaldehyde. In many cases, the threshold temperature is in the range of 100 to 160 degrees celsius, and therefore the level of undesired compounds can be effectively controlled in the extraction process.

The inventors of the present invention have found that for certain tobacco types, the level of certain undesirable nitrogenous compounds, such as TSNA, released during extraction is dependent on the extraction temperature. For flue-cured tobacco, the content of nitrogenous compounds is typically very low, and an increase in extraction temperature has very little effect on the level of TSNAs released during the extraction process. Burley tobacco, on the other hand, typically has a much higher content of nitrogenous compounds and it has been found that the amount of TSNA released on heating varies significantly depending on the extraction temperature, with a direct correlation between extraction temperature and released TSNA levels.

The inventors of the present invention have also found that for certain tobacco types, the level of the particular undesirable furan, 2-furancarbinol, released during extraction is dependent on the extraction temperature. For burley tobacco, the reducing sugar content is typically very low (below 2 wt%), and an increase in extraction temperature has very little effect on the level of 2-furancarbinol released in the extraction process. Flue-cured tobacco, on the other hand, typically has a much higher reducing sugar content (up to 25 wt%), and it has been found that the amount of 2-furancarbinol released upon heating varies significantly depending on the extraction temperature, with a direct correlation between the extraction temperature and the level of 2-furancarbinol released. The degree of increase in the level of 2-furancarbinol released from the flue-cured tobacco as the extraction temperature is increased may be different for each tobacco type.

As described herein, during the heating step in the extraction process, the tobacco starting material is heated to an extraction temperature of between about 100 and 160 degrees celsius. It has been found that if the tobacco starting material is heated to a temperature above this range, the weight of phenol in the resulting composition is much higher relative to the weight of beta-ionone and beta-damascone, resulting in a lower weight ratio of beta-ionone and beta-damascone to phenol.

4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone (NNK), (R, S) -N-Nitrosoanatabine (NAT), (R, S) -N-Nitrosoanabasine (NAB), and N-nitrosonornicotine (NNN) are TSNA. As described herein, these undesirable compounds are derived in relatively high amounts from tobacco having a high content of nitrogenous compounds, such as burley tobacco, and it has been found that the amount of TSNA released upon heating varies significantly with extraction temperature, with a direct correlation between extraction temperature and the level of TSNA released.

As described herein, 2-furancarbinols are derived in relatively high amounts from tobacco with a high content of reducing sugars, such as flue-cured tobacco, and it has been found that the amount of 2-furancarbinol released upon heating varies significantly depending on the extraction temperature, with a direct correlation between the extraction temperature and the level of 2-furancarbinol released.

As described herein, during the heating step in the extraction process, the tobacco starting material is heated to an extraction temperature of between about 100 and 160 degrees celsius. It has been found that if the tobacco starting material is heated to a temperature above this range, the weight of TSNA and 2-furancarbinol in the resulting composition is much higher relative to the weight of beta-ionone and beta-damascenone, resulting in a lower weight ratio of (beta-ionone + beta-damascenone) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-Nitrosoanabasine (NAB) and N-nitrosonornicotine (NNN) + (2-furancarbinol/600).

Tobacco is typically present in higher weight percentages in extracts produced from burley tobacco relative to flue-cured tobacco, but certain undesirable nitrogenous compounds such as TSNAs are typically derived from burley tobacco in higher amounts relative to flue-cured tobacco. Certain desirable flavor compounds, such as furanones, are derived from reducing sugars and are generally present in higher amounts in flue-cured tobacco relative to burley tobacco due to the higher reducing sugars of the former, but certain undesirable compounds, such as 2-furancarbinol, are also derived from reducing sugars and are generally present in higher amounts in flue-cured tobacco relative to burley tobacco. Thus, the liquid tobacco extract of the present invention is preferably prepared from a blend of different tobacco types. Preferably, the liquid tobacco extract is from burley tobacco and flue-cured tobacco. The flue-cured tobacco may be one or more of oriental tobacco and flue-cured tobacco.

During the heating step, the tobacco starting material is heated to an extraction temperature of between about 100 degrees celsius and about 160 degrees celsius. It has been found that below this range, insufficient levels of nicotine and certain flavor compounds are released from the tobacco starting material such that the resulting liquid tobacco extract lacks desirable flavor characteristics. On the other hand, if the tobacco starting material is heated to a temperature above this defined range, unacceptably high levels of certain undesirable tobacco compounds, such as phenol, TSNA, and 2-furancarbinol, may be released.

Preferably, the extraction temperature is at least about 110 degrees Celsius, more preferably at least about 115 degrees Celsius, more preferably at least about 120 degrees Celsius, more preferably at least about 125 degrees Celsius.

Preferably, the extraction temperature is no more than about 150 degrees Celsius, more preferably no more than about 145 degrees Celsius, more preferably no more than about 140 degrees Celsius, and most preferably no more than about 135 degrees Celsius.

For example, the extraction temperature may be between about 110 degrees celsius and 150 degrees celsius, or between about 120 degrees celsius and about 140 degrees celsius, or between about 125 degrees celsius and about 135 degrees celsius, or about 130 degrees celsius. It has been found that an extraction temperature of about 130 degrees celsius provides a particularly optimized ratio of desired to undesired compounds in the liquid tobacco extract.

The tobacco starting material is heated at the extraction temperature for at least about 30 minutes or at least about 60 minutes or at least about 90 minutes, more preferably at least about 120 minutes. The extraction time is sufficiently long so that the desired tobacco flavor compounds can be effectively extracted to provide a liquid tobacco extract that can form a nicotine composition that can produce an aerosol with the desired flavor characteristics.

Preferably, the tobacco starting material is heated at the extraction temperature for no more than about 270 minutes, more preferably no more than about 180 minutes.

For example, the tobacco starting material can be heated for about 90 minutes to about 270 minutes, or about 120 minutes to about 180 minutes.

The above heating time corresponds to the time the tobacco starting material is heated at the extraction temperature, excluding the time desired for raising the temperature of the tobacco starting material to the extraction temperature.

Typically, upon heating of the natural tobacco material, any moisture present in the natural tobacco material is also released in vapour form along with the volatile substances.

The heating step is preferably carried out in an inert atmosphere. For example, the natural tobacco material may be heated in a flow of inert gas or a combination of inert gas and water or steam. Preferably, during the heating step, a flow of inert gas, such as nitrogen, is passed through the starting tobacco material. Alternatively, the heating step may be performed under vacuum.

The inventors have found that heating a natural tobacco material in an inert atmosphere is advantageous in that volatile tobacco compounds are released into the inert gas stream during the heating step, such that the inert gas acts as a carrier for the volatile components.

The inert gas flow helps to transport the vapors and volatile substances (including especially nicotine or flavor-related compounds or both) generated by evaporation of the moisture content of the natural tobacco material out of the extraction device.

Furthermore, the use of a flow of inert gas, for example nitrogen, at a slight overpressure in the extraction device has the advantage of preventing the presence of oxygen in the extraction device. This can also be achieved by performing the heating step under vacuum. This benefit is desirable as it prevents any risk of even partial combustion of the natural tobacco material during the heating step. Uncontrolled combustion of natural tobacco material is clearly undesirable as it represents a major safety risk in a manufacturing environment. However, the present inventors have found that even limited, partial combustion of natural tobacco material may result in a reduction in the quality of the tobacco extract obtainable by this method, which would be undesirable.

Without wishing to be bound by theory, it is understood that by preventing combustion of the natural tobacco material, the formation of any undesirable combustion byproducts is also prevented. In addition, because conditions that would be conducive to combustion of the natural tobacco material are prevented, it is somewhat analogous to the conditions under which tobacco-containing substrates (e.g., homogenized tobacco material) are typically heated in "heat-not-burn" type articles, effectively heating the natural tobacco material. As a result, selective extraction of flavor-bearing volatile substances responsible for the taste consumer associated with heating the tobacco is facilitated.

Therefore, by performing the second heating step in an inert atmosphere, the extraction efficiency, product quality and manufacturing safety are advantageously improved.

The inert gas flow rate may be optimized based on the size and geometry of the extraction chamber. The relatively high flow rate of inert gas may advantageously further enhance the efficiency of extraction from the tobacco starting material.

It has been found that the addition of water or steam to the tobacco during extraction can improve the yield of the extracted components. However, excessive addition of water or steam leads to processing difficulties, such as the stickiness of the tobacco material. Suitable heating methods for effecting heating of the tobacco starting material are known to the skilled person and include, but are not limited to: dry distillation, water distillation, vacuum distillation, flash evaporation and thin film water distillation.

Optionally, the tobacco starting material may be digested with enzymes prior to the heating step. This has been found to provide a significant increase in the yield of certain flavour compounds from tobacco starting materials.

Prior to the heating step, the tobacco starting material can optionally be analyzed to determine composition, e.g., reducing sugar content of the alkaloid. This information about the composition can be helpful for selecting an appropriate extraction temperature.

During heating of the tobacco starting material, volatile compounds released from the tobacco starting material are collected using any suitable technique. As described above, volatile compounds are collected from the inert gas stream as the tobacco starting material is heated in the inert gas stream. Different collection methods are known to the person skilled in the art.

Preferably, the step of collecting the volatile compounds uses an absorption technique in which the volatile compounds are trapped in a non-aqueous solvent. For example, an inert gas stream containing the volatile compounds can be introduced into the vessel of the non-aqueous extraction solvent. The non-aqueous extraction solvent is preferably an aerosol former. The non-aqueous solvent is preferably triacetin, glycerin, Propylene Glycol (PG), 1, 3-propanediol, or a mixture thereof. The non-aqueous extraction solvent may be a polyol. The use of an aerosol former as a non-aqueous extraction solvent is potentially beneficial because the aerosol former may remain as a diluent in the final liquid tobacco extract and nicotine composition. This means that no additional step of removing the non-aqueous extraction solvent is necessary.

In a preferred embodiment, the volatile compounds are collected by condensation and the condensate obtained is added to a liquid aerosol former, preferably PG.

The addition of a liquid aerosol former, particularly PG, can advantageously prevent the condensed volatile compounds from splitting into two phases or forming an emulsion, as some tobacco ingredients will tend to do so. Without wishing to be bound by theory, the inventors have observed that the solubility of tobacco components in the hydrolysate (i.e. the aqueous fraction of the liquid, the naturally derived tobacco extract) depends mainly on their polarity, their concentration and the pH of the hydrolysate, which may vary according to the tobacco type. As a result, if the amount of aerosol former is insufficient, an oil layer tends to form on the surface of the tobacco extract liquid of natural origin. This oily material can accumulate at different locations on the collection apparatus where the collection step is performed. The addition of a liquid aerosol former such as PG helps to prevent the formation of such layers and facilitates homogenization of the liquid natural tobacco extract. This in turn helps to prevent the loss of any desired flavour related compounds during the fourth (drying) step, where these compounds may undesirably deposit on the device surfaces.

Furthermore, the liquid aerosol former advantageously helps to trap flavour related compounds regardless of their polarity and volatility. Furthermore, the liquid aerosol former helps to prevent loss of the most volatile portion during the fourth (drying) step, as well as to facilitate selective removal of excess water from the liquid, naturally-derived tobacco extract to obtain a concentrated tobacco extract.

The use of PG as an aerosol former for the condensation and collection step has the further advantage that PG exerts antimicrobial activity by reducing the water activity of the aqueous solution. By adjusting the content of PG in the liquid of the tobacco extract of natural origin, it is therefore also possible to ensure that the extract does not substantially undergo any microbial activity.

The liquid, naturally derived tobacco extract obtained at the end of the collection step is typically a homogeneous liquid. This homogeneous liquid can be stored for a limited holding time (up to about 4 weeks) before being subjected to an optional drying step. The composition of liquid tobacco extracts of natural origin depends on a number of variables, including the nature of the natural tobacco material; moisture content in natural tobacco material; the amount of aerosol former, if any, used to prepare the natural tobacco material.

Preferably, the non-aqueous extraction solvent is maintained at a temperature below 0 degrees celsius in order to optimize the transfer of volatile compounds into the non-aqueous extraction solvent. The non-aqueous extraction solvent is preferably maintained at a temperature of not less than-10 ℃. Temperatures below this value may lead to undesirable freezing phenomena.

As an alternative to absorption techniques, the step of collecting volatile compounds may be performed using condensation techniques, wherein the volatile compounds are condensed and the condensate is collected. The condensation of the volatile compounds can be carried out using any suitable means, for example in a cooling tower. In the case where the volatile compounds are collected by condensation, the step of forming a liquid tobacco extract may comprise adding the condensate to a non-aqueous extraction solvent, such as an aerosol former.

Alternatively, the step of collecting the volatile compounds may be carried out using an adsorption technique in which the volatile compounds are adsorbed onto the surface of a solid adsorbent material, such as activated carbon. The adsorbed compound is then transferred to a non-aqueous extraction solvent.

Optionally, the step of forming a liquid tobacco extract comprises a filtration step.

Optionally, the step of forming a liquid tobacco extract comprises a blending step wherein extracts derived from different tobacco starting materials are combined.

In this process, the next step is to form a liquid tobacco extract from the collected volatile compounds. The nature of this step may depend on the collection method. "collected volatile compounds" generally include solutions of tobacco-derived volatile compounds in a non-aqueous extraction solvent.

The extraction process provides a liquid tobacco extract comprising greater than about 20% by weight water, based on the weight of the liquid tobacco extract. Typically, the liquid tobacco extract may comprise at least about 40% by weight water. The liquid tobacco extract may comprise from about 40% to about 70% by weight water.

The extraction process described herein provides a liquid tobacco extract having a nicotine content of at least 0.2 wt.%. More preferably, the nicotine content in the liquid tobacco extract is at least about 0.4% by weight. The nicotine content of the liquid tobacco extract can be no more than about 10% by weight, more preferably no more than about 8% by weight, more preferably no more than about 5% by weight, and most preferably no more than about 3.6% by weight. Most preferably, the liquid tobacco extract comprises about 0.4 to 3.6 weight percent nicotine based on the weight of the liquid tobacco extract.

The extraction process described herein provides a liquid tobacco extract that may have a non-aqueous extraction solvent content of from about 25% to about 65% by weight, preferably from about 30% to 60% by weight, most preferably from about 35% to about 55% by weight. The non-aqueous extraction solvent is preferably triacetin, glycerol, propylene glycol, 1, 3-propanediol, or a mixture thereof.

The nicotine composition may advantageously be formed directly from a liquid tobacco extract produced by an extraction process without the need for adding additional nicotine. The nicotine composition may advantageously be formed directly from a liquid tobacco extract produced by an extraction process without the need for the addition of other flavor compounds. The nicotine composition may advantageously be formed directly from a liquid tobacco extract without the need for adding additional non-aqueous solvents. For example, the liquid tobacco extract resulting from the extraction process can be used to prepare a nicotine composition comprising 10 to 20mg nicotine per ml without the need for adding nicotine.

Alternatively, the liquid tobacco extract can be subjected to additional processing steps to form the nicotine composition. Even when such additional steps are performed, a nicotine composition can be formed without the need to add additional nicotine or flavor compounds. Preferably, the liquid tobacco extract can be concentrated in a drying step, such as the drying step described herein, to form a concentrated tobacco extract. The concentrated tobacco extract can be used to form a nicotine composition. Preferably, additional non-aqueous solvents may be added to the liquid tobacco extract or the concentrated tobacco extract to form the nicotine composition.

When the volatile compounds are collected by absorption in the non-aqueous extraction solvent, as described above, it is preferred to dry the solution of volatile compounds in the liquid solvent to form a liquid tobacco extract in order to concentrate the solution, as the liquid solvent may include both the non-aqueous extraction solvent and water. This may be done, for example, to achieve a desired concentration of nicotine or flavor compounds. Drying may be carried out using any suitable means, including but not limited to drying, molecular sieving, freeze drying, phase separation, distillation, membrane permeation, controlled crystallization and filtration of water, reverse hygroscopicity, ultracentrifugation, liquid chromatography, reverse osmosis, or chemical drying.

The concentrated tobacco extract is preferably formed by concentrating a solution of the volatile compounds in a liquid solvent by drying in a drying step to form a liquid tobacco extract. The concentrated tobacco extract can be used to form a nicotine composition.

In the drying step, a solution of the volatile compound in a liquid solvent is heated to evaporate at least some of the water and obtain a concentrated tobacco extract. To this end, a solution of the volatile compound in a liquid solvent may be heated to a temperature and for a time such that the water content in the tobacco extract is reduced by at least about 60%.

In one embodiment, a solution of the volatile compound in the liquid solvent is heated under vacuum, preferably at a temperature of at least about 70 ℃. In another embodiment, the solution of the volatile compound in the liquid solvent is heated in an air stream, preferably an air stream having a relatively low humidity, at a temperature of at least about 35 degrees celsius. Thus, a concentrated tobacco extract can be obtained. One such concentrated tobacco extract typically contains less than about 20% by weight water.

In the drying step, the liquid tobacco extract may be heated from about 35 degrees celsius to about 95 degrees celsius, more preferably from about 35 degrees celsius to about 90 degrees celsius, even more preferably from about 35 degrees celsius to about 85 degrees celsius, and most preferably from about 35 degrees celsius to about 80 degrees celsius.

In the drying step, the liquid tobacco extract may be heated under reduced pressure. The liquid tobacco extract can be heated at a pressure of less than or equal to about 200 millibars. In the drying step, the liquid tobacco extract may be heated at a pressure of at least about 20 mbar.

Alternatively, in the drying step, the liquid tobacco extract may be heated under a stream of air. The liquid tobacco extract may be heated under a flow of air of at least about 10 kg/h. The liquid tobacco extract may be heated under a flow of air of at least about 15 kg/h. The relative humidity of the air stream may be less than or equal to about 50%, preferably less than or equal to about 25%.

After the drying step, the liquid tobacco extract is referred to as a concentrated tobacco extract. The concentrated tobacco extract comprises less than or equal to about 20% by weight water. Preferably, the concentrated tobacco extract comprises from 8 wt% to 15 wt% water, based on the weight of the concentrated tobacco extract.

The drying step provides a concentrated tobacco extract that may have a non-aqueous extraction solvent content of about 65% to about 95% by weight, preferably about 65% to 85% by weight, most preferably about 75% to about 85% by weight. The non-aqueous extraction solvent is preferably triacetin, glycerol, propylene glycol, 1, 3-propanediol, or a mixture thereof.

The drying step provides a concentrated tobacco extract that can have a nicotine content of at least about 0.2% by weight nicotine, preferably from about 0.5% to about 12% by weight nicotine, and most preferably from about 2% to about 8% by weight nicotine.

The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of additional nicotine. The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of an additional non-aqueous solvent. The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of additional water. The concentrated tobacco extract can be used directly to form a nicotine composition without the addition of additional flavorants.

Preferably, additional non-aqueous solvents may be added to the liquid tobacco extract or the concentrated tobacco extract to form the nicotine composition.

The liquid tobacco extract, the concentrated tobacco extract and the nicotine composition may have optional and preferred features as previously described herein.

The invention will now be further described with reference to the following examples.

Detailed Description

Examples

Example 1

A tobacco starting material prepared from a smoked tobacco material. The tobacco material is cut to form tobacco pieces having dimensions of 2.5 mm x 2.5 mm and the tobacco pieces are loaded into the extraction chamber without compression. The tobacco starting material was heated in the extraction chamber to a temperature of 130 degrees celsius for a period of 3 hours. During heating, a nitrogen stream was passed through the extraction chamber at a flow rate of about 40 liters/minute.

Volatile compounds released from the tobacco starting material during the heating step were collected by absorption into the liquid solvent formed from propylene glycol at-10 ℃ and with stirring at 750 rpm.

A liquid tobacco extract is obtained directly in an extraction process at a temperature of 130 deg.C for 3 hours. The liquid tobacco extract provides optimized levels of desirable flavor compounds such as beta-damascenone and beta-ionone relative to undesirable compounds such as phenol, 4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone, (R, S) -N-nitrosoanatabine, (R, S) -N-nitrosoanabasine, N-nitrosonornicotine, and 2-furancarbinol. In particular, the liquid tobacco extract contains greater than 0.2% by weight nicotine based on the weight of the liquid tobacco extract. Further, in the liquid tobacco extract, the weight ratio of (beta-ionone + beta-damascone) to (phenol) is greater than 0.25.

Example 2

This example provides two concentrated tobacco extracts obtained from separate extraction processes at a temperature of 130 degrees celsius over a period of 3 hours, each process being followed by a drying step to reduce the moisture level of the liquid tobacco extract to about 6%. Both liquid tobacco extracts contain greater than 0.2% by weight nicotine based on the weight of the liquid tobacco extract. Furthermore, in both liquid tobacco extracts the weight ratio of (β -ionone + β -damascone) to (phenol) is greater than 0.25.

Example 2a

Example 2a relates to a concentrated tobacco leaf extract derived from a smoked flue-cured tobacco material. The content of the liquid tobacco extract of example 2a was as follows:

■ Nicotine: 0.53% w/w

■ propylene glycol: 91.8% w/w

■ water: 6.3% w/w

■ balance (including the fragrances detailed in table 1 below): 1.57% w/w

Example 2b

Example 2b relates to a concentrated tobacco extract derived from burley tobacco material. The content of the liquid tobacco extract of example 2b was as follows:

■ Nicotine: 1.82% w/w

■ propylene glycol: 89.6% w/w

■ water: 5.7% w/w

■ balance (including the fragrances detailed in table 1 below): 2.88% w/w

TABLE 1 content of selected flavor compounds in concentrated tobacco extracts (all values are given in micrograms/kg liquid tobacco extract)

Examples 2a and 2b of the present invention contain acceptably low levels of undesirable compounds such as phenol, 4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone, (R, S) -N-nitrosoanatabine, (R, S) -N-nitrosoanabasine, N-nitrosonornicotine and 2-furancarbinol.

Example 3

This example provides three concentrated tobacco extracts obtained from separate extraction processes at a temperature of 130 degrees celsius over a period of 3 hours, each process being followed by a drying step to reduce the moisture level of the liquid tobacco extract to about 12.5%. All of these liquid tobacco extracts contain greater than 0.2% by weight nicotine based on the weight of the liquid tobacco extract. Furthermore, in these liquid tobacco extracts, the weight ratio of (β -ionone + β -damascone) to (phenol) is greater than 0.25.

Example 3a

Example 3a relates to a concentrated tobacco extract derived from oriental tobacco material. The content of the concentrated tobacco extract of example 3a was as follows:

■ Nicotine: 0.4% w/w

■ propylene glycol: 84% w/w

■ acetic acid: 1.0% w/w

■ water: 12.5% w/w

■ balance (including perfume): 2.1% w/w

Example 3b

Example 3b relates to a concentrated tobacco extract derived from a smoked flue-cured tobacco material. The content of the concentrated tobacco extract of example 3b was as follows:

■ Nicotine: 1.2% w/w

■ propylene glycol: 84% w/w

■ acetic acid: 1.0% w/w

■ water: 12.5% w/w

■ balance (including perfume): 1.3% w/w

Example 3c

Example 3c relates to a concentrated tobacco extract derived from burley tobacco material. The content of the concentrated tobacco extract of example 3c was as follows:

■ Nicotine: 2.6% w/w

■ propylene glycol: 84% w/w

■ acetic acid: 0.5% w/w

■ water: 12.5% w/w

■ balance (including perfume): 0.4% w/w

The concentrated tobacco extract of example 3 provides optimized levels of desirable flavor compounds such as beta-damascenone and beta-ionone relative to undesirable compounds such as phenol, 4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone, (R, S) -N-nitrosoanatabine, (R, S) -N-nitrosoanabasine, N-nitrosonornicotine and 2-furancarbinol.

Example 4

The liquid tobacco extract of example 1 was concentrated during drying to reduce the moisture level of the liquid tobacco extract to about 15%.

Glycerin is added to the resulting concentrated tobacco extract to form a nicotine composition such that the nicotine composition contains 20% by weight glycerin and 80% by weight liquid tobacco extract, based on the weight of the nicotine composition.

Example 5

Example 5 relates to a nicotine composition in the form of a gel. A gel nicotine composition is formed from the liquid tobacco extract of example 1. The content of the gel nicotine composition was as follows:

■ liquid tobacco extract of example 1: 99.0% w/w

■ agar: 1.0% w/w

Example 6

The three tobacco starting materials of the invention are prepared from a flue-cured tobacco starting material (6A), a burley tobacco starting material (6B) and an oriental tobacco starting material (6C), respectively.

Each of the three tobacco materials was cut to form tobacco pieces having a size of 2.5 mm by 2.5 mm, and the tobacco pieces were loaded into the extraction chamber without compression.

Each tobacco starting material was heated to a temperature of 130 degrees celsius for 120 minutes in an extraction chamber. During the heating, a nitrogen flow was passed through the extraction chamber at a flow rate of 2 liters/min.

Volatile compounds released from each tobacco starting material during the heating step were collected by absorption into a liquid solvent formed from polypropylene glycol at 0 degrees celsius.

A liquid tobacco extract is obtained directly from the extraction process. Each liquid extract obtained from each of the three tobacco starting materials was then concentrated under vacuum (50 mbar) at 55 degrees celsius until a moisture content of 12% ± 2% was reached.

TABLE 2 selected weight ratios of desired tobacco compounds to undesired tobacco compounds in liquid tobacco extracts

In all three liquid extracts 6A, 6B and 6C according to the invention, the weight ratio of (β -ionone + β -damascone) to (phenol) is consistent and significantly higher than 2.0. Furthermore, in all three liquid extracts 6A, 6B and 6C according to the invention, the weight ratio of (furanone + (2, 3-diethyl-5-methylpyrazine) × 100)) to (nicotine) is consistent and significantly higher than 1 × 10^-3. Furthermore, in all three liquid extracts 6A, 6B and 6C according to the invention, the weight ratio of (β -ionone + β -damascone) to (4- (methylnitrosamino) -1- (3-pyridyl) -1-butanone + (R, S) -N-nitrosoanatabine + (R, S) -N-nitrosoanabasine + N-nitrosonornicotine + ((2-furancarbinol)/600)) is consistent and significantly higher than 3.

Comparative example

Two tobacco starting materials were prepared from flue cured tobacco material (CE1, CE 2). Two other tobacco starting materials are prepared from burley tobacco material (CE3, CE 4). Each of the four starting tobacco materials was cut to form tobacco pieces having dimensions of 2.5 mm by 2.5 mm.

The tobacco fragments are mixed with an alkaline solution of potassium carbonate in water to bring each tobacco material to a predetermined pH. One such alkaline treatment of starting tobacco material is described in US 2016/360780.

In more detail, the tobacco starting materials CE1 and CE3 were mixed with an alkaline solution of potassium carbonate in water to reach pH 8, while the tobacco starting materials CE2 and C4 were mixed with an alkaline solution of potassium carbonate in water to reach pH 9.5.

After this alkali treatment, the tobacco fragments of each tobacco starting material are loaded into the extraction chamber without compression. Each tobacco starting material was heated to a temperature of 130 degrees celsius for 120 minutes in the extraction chamber. During heating, a nitrogen stream was passed through the extraction chamber at a flow rate of about 2 liters/minute.

Volatile compounds released from each tobacco starting material during the heating step were collected by absorption into a liquid solvent formed from polypropylene glycol at 0 degrees celsius.

A liquid tobacco extract is obtained directly from the extraction process. Each liquid extract obtained from each of the four tobacco starting materials was then concentrated under vacuum (50 mbar) at 55 degrees celsius until a moisture content of 12% ± 2% was reached.

TABLE 3 selected weight ratios of desired tobacco compounds to undesired tobacco compounds in liquid tobacco extracts

In all four liquid extracts according to comparative examples CE1, CE2, CE3 and CE4, the weight ratio of (β -ionone + β -damascone) to (phenol) was consistent and significantly lower than 0.25. Furthermore, in all four liquid extracts according to comparative examples CE1, CE2, CE3 and CE4, the weight ratio of (furanone + (2, 3-diethyl-5-methylpyrazine) × 100)) to (nicotine) was consistently and significantly lower than 5 × 10^-4。