Improved tobacco-flavored dry powder formulations

Abstract

A tobacco-flavored dry powder formulation is provided, comprising a substrate and a plurality of particles comprising a tobacco flavoring composition, wherein a first weight ratio of (β-ionone + β-damascenone) to (phenol) in the tobacco-flavored dry powder formulation is greater than 0.25. Also provided is a method of making such a tobacco-flavored powder formulation. The method includes preparing a tobacco starting material; heating the tobacco starting material at an extraction temperature of 100°C to 160°C for at least 90 minutes; collecting volatile compounds released from the tobacco starting material during the heating step; forming a liquid tobacco flavoring composition comprising the collected volatile compounds; and combining the substrate and the liquid tobacco flavoring composition to form tobacco-flavored particles.

Description

[Technical Field]

[0001] The present invention relates to tobacco-flavored dry powder formulations for inhalation that may find use as components of powder systems that include both nicotine-containing particles and flavor-containing particles, e.g., where the flavor particles are larger than the nicotine particles. Additionally, the present invention relates to methods of making the tobacco-flavored powder particles. [Background technology]

[0002] Dry powder inhalers (DPIs) are known and are used to treat respiratory disorders by delivering a dry powder containing a medication in the form of an aerosol to a patient's airway via inhalation. Typically, DPIs are breath-actuated devices that deliver medication in the form of particles contained in a capsule or blister that is pierced before use. Because the medication is processed, weighed, and filled in powder form, there is minimal risk of degradation, segregation, and microbial contamination compared to wet formulations.

[0003] For delivery into the lungs, particles in the 1-5 micrometer range are preferred. In pharmaceutical dry powders, the active pharmaceutical ingredient (API) may be agglomerated on the surface of larger carrier particles (such as lactose). Pharmaceutical dry powders containing lactose as a carrier can be in the 20-100 micrometer range. DPIs operate through a complex mechanism to ensure that these agglomerates are dispersed, broken up, or deagglomerated, allowing the API to then be inhaled into the lungs.

[0004] DPIs rely on the patient's inhalation force to mix the powder from the inhalation device and then grind the powder into particles small enough to enter the lungs. A sufficiently high inhalation volume is required to ensure the correct dose and complete deagglomeration of the powder. A large amount of the API typically remains attached to the carrier surface and is deposited in the upper respiratory tract due to incomplete deagglomeration of the powder. The inhalation volume of existing DPIs is typically in the range of 20 to 100 liters per minute (L / min). Therefore, existing DPIs are only suitable for delivering dry powder to the user in a manner that differs from the inhalation volume associated with smoking articles.

[0005] Therefore, existing DPIs are generally not suitable for delivering dry powder particles to the lungs in a manner consistent with traditional smoking. For example, DPIs often attempt to provide the entire dry powder dose in a single breath. In contrast, traditional smoking involves many pleasant puffs.

[0006] Solutions to this problem have been proposed, for example, in WO 2019 / 003118, which describes a receptacle or capsule, a powder system, and an inhaler article adapted to deliver particles to the lungs at an inhalation or airflow rate within the range of that of traditional smoking. A consumer may take multiple inhalations or "puffs," each "puff" delivering a uniform portion of the dry powder contained in the receptacle or capsule housed within the capsule cavity of the inhaler article described in WO 2019 / 003118. The inhaler article may have a form similar to a traditional cigarette, mimic the routine of traditional smoking, and provide a preferred or enjoyable form of nicotine delivery. In some embodiments, the inhaler article is adapted to deliver a powder system including a first plurality of particles and a second plurality of particles. The first plurality of particles has a larger particle size than the second plurality of particles. The first plurality of particles may be nicotine-free and may include a flavor component, and is preferably free-flowing. The second plurality of particles comprises nicotine and is preferably free-flowing.

[0007] A process is known from US 6,056,949 for the preparation of substantially spherical, flowable, mechanically stable, and virtually dust-free aromatic and odorous granular materials with a narrow particle size distribution. According to US 6,056,949, any conventional flavor or odorant can be used to prepare such dry powders, including fruit (such as citrus), strawberry, tobacco, flowers, wood, spices, and amber. The powder particles obtained by the process of US 6,056,949 are described as having a size of 0.2 to 1 millimeter.

[0008] EP3393451 discloses a powder system comprising nicotine-containing particles and flavor-containing particles, the flavor particles being larger than the nicotine particles. The majority of the flavor particles in the system have a particle size of about 20 micrometers or more, preferably about 50 micrometers or more. Furthermore, the flavor particles in the system preferably have a particle size of about 150 micrometers or less.

[0009] EP 3478264 discloses a nicotine powder containing sugars and amino acids. EP 3478265 discloses a nicotine powder obtained by spray drying and milling.

[0010] It would be desirable to provide novel tobacco-flavored dry powders, particularly for use in inhaler devices adapted to provide an inhalation dose typically associated with smoking articles, that minimize the content of undesirable tobacco-derived compounds, while at the same time providing such improved tobacco-flavored dry powders that have high levels of desirable tobacco-related flavor species.

[0011] It would be desirable to provide such an improved tobacco-flavored dry powder that can be easily used in an inhaler device associated with a conventional smoking method or in the manufacture of a powder system for use in one such inhaler device.

[0012] It would likewise be desirable to provide a method for the production of such improved tobacco flavored dry powders that can be efficiently carried out, particularly using existing equipment and technology. Summary of the Invention

[0013] The present disclosure relates to a tobacco-flavored dry powder formulation comprising a plurality of particles. The particles may comprise a substrate and a tobacco flavoring composition. A first weight ratio of (β-ionone + β-damascenone) to (phenol) in the tobacco-flavored dry powder formulation may be greater than 0.25.

[0014] Additionally, the present disclosure relates to a method of making a tobacco-flavored powder formulation. The method may include preparing a tobacco starting material. The method may include heating the tobacco starting material at an extraction temperature of 100 degrees Celsius to 160 degrees Celsius for at least 90 minutes. The method may further include collecting volatile compounds released from the tobacco starting material during the heating step. The method may include forming a liquid tobacco flavorant composition including the collected volatile compounds. The method may include combining a substrate and the liquid tobacco flavorant composition to form tobacco-flavored particles.

[0015] The present disclosure further relates to a powder system comprising a first plurality of particles and a second plurality of particles. The first plurality of particles may have a particle size of at least about 20 micrometers. The second plurality of particles may have a particle size of about 10 micrometers or less. The first plurality of particles may comprise a substrate and a tobacco flavorant composition. The first weight ratio of (β-ionone + β-damascenone) to (phenol) in the tobacco flavorant composition may be greater than 0.25. The second plurality of particles may comprise nicotine. Furthermore, the second plurality of particles may comprise a sugar and an amino acid.

[0016] The present disclosure further relates to a powder system including a first plurality of tobacco-flavored particles. The tobacco-flavored particles may have a particle size of at least about 20 micrometers. The powder system may include a second plurality of particles. The second plurality of particles may have a particle size of less than about 20 micrometers. A first weight ratio of (β-ionone + β-damascenone) to (phenol) in the first plurality of tobacco-flavored particles may be greater than 0.25.

[0017] According to the present invention, there is provided a tobacco-flavored dry powder formulation comprising a substrate and a plurality of particles comprising a tobacco flavorant composition, wherein a first weight ratio of (β-ionone + β-damascenone) to (phenol) in the tobacco-flavored dry powder formulation is greater than 0.25.

[0018] The present invention also provides a method for making a tobacco-flavored powder formulation. The method includes a first step of preparing a tobacco starting material. The method includes a second step of heating the tobacco starting material at an extraction temperature of 100°C to 160°C for at least 90 minutes. The method includes a third step of collecting volatile compounds released from the tobacco starting material during the heating step. The method includes a fourth step of forming a liquid tobacco flavorant composition containing the collected volatile compounds. The method includes a fifth step of combining a substrate with the liquid tobacco flavorant composition to form tobacco-flavored particles.

[0019] The present invention further provides a powder system comprising a first plurality of particles and a second plurality of particles. The first plurality of particles has a particle size of at least about 20 micrometers. The second plurality of particles has a particle size of about 10 micrometers or less. The first plurality of particles comprises a substrate and a tobacco flavorant composition. A first weight ratio of (β-ionone + β-damascenone) to (phenol) in the tobacco flavorant composition is greater than 0.25. The second plurality of particles comprises nicotine.

[0020] The present invention also provides a powder system comprising a first plurality of tobacco flavored particles having a particle size of at least about 20 micrometers and a second plurality of particles having a particle size of less than about 20 micrometers, wherein a first weight ratio of (β-ionone + β-damascenone) to (phenol) in the first plurality of tobacco flavored particles is greater than 0.25.

[0021] It will be understood that any feature described below in relation to the tobacco-flavored dry powder formulation of the present invention, or the method of making the tobacco-flavored dry powder formulation of the present invention, or the powder system of the present invention, is equally applicable to any other powder formulation, method, and powder system.

[0022] The term "dry powder formulation" as used herein in connection with the present invention means a formulation containing finely dispersed solid particles having a particular particle size distribution that can be easily dispersed in or through an inhaler and administered to a subject via inhalation so that a portion of the particles reach the tissues of the oral cavity or upper respiratory tract, e.g., the pharynx or throat in general. Depending on the size of the particles as defined by their aerodynamic diameter, the particles of the dry powder formulation may also be suitable for pulmonary administration.

[0023] As used herein, particle size preferably refers to the aerodynamic diameter of the particle, which is defined as the diameter of a sphere having a density of 1 gram per cubic centimeter that would settle in still air at the same velocity as the particle in question.

[0024] In particular, powder systems generally refer to the mass median aerodynamic diameter (MMAD), which is one of the most widely adopted indicators as a single numerical descriptor of the aerodynamic particle size distribution. MMAD is a statistically derived numerical value for a particle sample; as an example, an MMAD of 5 micrometers means that 50 percent of the total sample mass is present in particles having an aerodynamic diameter less than 5 micrometers, and the remaining 50 percent of the total sample mass is present in particles having an aerodynamic diameter greater than 5 micrometers. In the context of the present invention, when describing a powder system, the term "particle size" preferably refers to the MMAD of the powder system.

[0025] The MMAD of powder systems is preferably measured using a cascade impactor. Cascade impactors are widely used devices for sampling and separating airborne particles to determine the aerodynamic size classification of aerosol particles. In practice, cascade impactors separate incoming samples into discrete fractions based on particle inertia, which is a function of particle size, density, and velocity. Cascade impactors typically include a series of stages, each of which contains a plate with a specific nozzle arrangement and collection surface. As the number of stages increases, both the nozzle size and total nozzle area decrease, so the velocity of the sample-laden air increases as it moves through the device. At each stage, particles with sufficient inertia are deflected from the main airflow and impact the collection surface. Thus, at any given flow rate, each stage is associated with a cutoff diameter, a feature that defines the size of particles that will be collected. As the number of stages increases, velocity increases and the stage cutoff diameter decreases. Therefore, the cutoff diameter associated with a given stage is a function of the airflow rate used in the test. To reflect in-use performance, nebulizers are routinely tested at 15 L / min and dry powder inhalers may be tested at flow rates up to 100 L / min.

[0026] In the context of the present invention, the MMAD of powder systems is preferably measured using a Next Generation Impactor (NGI) 170 (available from Copley Scientific AG). The NGI is a high-performance, high-precision particle-classifying cascade impactor with seven stages and a micro-orifice collector (MOC). The characteristics and operating principle of the NGI are described, for example, in Marple et al., Journal of Aerosol Medicine—Volume 16, Number 3 (2003). More preferably, measurements are performed at 20±3 degrees Celsius and 35±5 percent relative humidity.

[0027] Dry powder formulations typically contain about 15 weight percent or less moisture, preferably about 10 weight percent or less moisture, and even more preferably about 6 weight percent or less moisture. Most preferably, dry powder formulations contain about 5 weight percent or less moisture, or about 3 weight percent or less moisture, or about 1 weight percent or less moisture.

[0028] In some embodiments, the dry powder formulation may contain about 1 weight percent to about 15 weight percent moisture, preferably about 3 weight percent to about 15 weight percent moisture, and even more preferably about 5 weight percent to about 15 weight percent moisture. In other embodiments, the dry powder formulation may contain about 1 weight percent to about 10 weight percent moisture, preferably about 3 weight percent to about 10 weight percent moisture, and even more preferably about 5 weight percent to about 10 weight percent moisture. In further embodiments, the dry powder formulation may contain about 1 weight percent moisture to about 10 weight percent moisture, preferably about 3 weight percent moisture to about 10 weight percent moisture, and even more preferably about 5 weight percent moisture to about 10 weight percent moisture.

[0029] In some particularly preferred embodiments, the dry powder formulation may contain from about 1 weight percent moisture to about 6 weight percent moisture, or from about 3 weight percent moisture to about 6 weight percent moisture, or from about 5 weight percent moisture to about 6 weight percent moisture.

[0030] The particles may be micro-sized or nano-sized. The particles may have a narrow particle size distribution.

[0031] The term "microsized" as used herein with respect to particles of a formulation according to the present invention broadly refers to particles having an average particle size of about 1 micrometer to about 10 micrometers. Particle size may refer to the diameter of a particle where the particle is substantially spherical. Particles may also be non-spherical, and particle size may refer to the equivalent diameter of the particle relative to a spherical particle.

[0032] The term "nanosized" as used herein in reference to particles of the formulations of the present invention broadly refers to particles having an average particle size of less than about 1000 nanometers, particularly from about 50 nanometers to about 1000 nanometers.

[0033] In the context of the present invention, the term "narrow particle size distribution" is used to indicate that the particles of a formulation according to the present invention have a Span value of less than about 2. Span value is defined arithmetically as Span = ([particle diameter at 90th percentile size] - [particle diameter at 10th percentile size]) / [particle diameter at 50th percentile size], or (D90 - D10) / D50.

[0034] As briefly described above, in contrast to existing dry powder formulations, the tobacco-flavored dry powder formulation according to the present invention comprises a plurality of particles comprising a base material and a tobacco flavorant composition, and a first weight ratio of (β-ionone + β-damascenone) to (phenol) in the tobacco-flavored dry powder formulation is greater than 0.25.

[0035] Thus, the present invention advantageously provides a tobacco-flavored dry powder formulation that can maximize the content of tobacco flavor-related compounds while simultaneously reducing the content of undesirable natural tobacco-derived compounds, such as furans and TSNAs. Furthermore, the inventors have discovered that the tobacco-flavored dry powder formulations of the present invention have a flavor closer to that of natural tobacco than powder formulations obtained from artificial blends containing synthetic compounds.

[0036] Additionally, preferred embodiments, described in detail below, advantageously provide reduced oral astringency and control of nicotine levels in tobacco-flavored dry powder formulations.

[0037] As briefly described above, tobacco flavored dry powder formulations can be obtained by a process that includes a first step of preparing a tobacco starting material, which is preferably a natural tobacco material.

[0038] The term "natural tobacco material" as used herein in connection with the present invention describes any part of any plant member of the genus Nicotiana, including, but not limited to, the leaves, midrib, stem, and petiole. In particular, natural tobacco materials may include full-cured tobacco materials, burley tobacco materials, Orient tobacco materials, Maryland tobacco materials, dark tobacco materials, dark-fired tobacco materials, rustica tobacco materials, and materials derived from other rare or specialty tobaccos, or blends thereof. As described in more detail below, the tobacco material may be whole (e.g., whole tobacco leaf), shredded, cut, ground, or aged. In some embodiments, the tobacco material may be a combination of one or more of whole, cut, ground, and aged.

[0039] The term "liquid tobacco flavor composition," as used herein in connection with the methods of the present invention, refers to the direct product of an extraction process performed on a tobacco starting material. Thus, a tobacco extract typically comprises a mixture of natural components that have been separated from, removed from, or derived from a natural tobacco material using tobacco extraction processing conditions and techniques. Thus, in one such process, extracted tobacco components are removed from the natural tobacco material and separated from non-extracted tobacco components.

[0040] Several methods are known for producing liquid tobacco extracts that can be used as liquid tobacco flavoring compositions. For example, WO 2017 / 144705 discloses a method in which tobacco material is heated to a temperature of 50 to 250 degrees Celsius, and volatile species released from the heated tobacco material are collected to produce a liquid formulation (also called e-liquid) for use in an e-vaping device.

[0041] Maceration methods are also known, in which tobacco material is held in suspension in an extraction liquid for up to several weeks or months. The resulting slurry is then filtered, and the collected liquid phase can be used to produce a vaporizable liquid formulation. In one such method, the so-called "cold maceration method," there is generally no way to control the extraction conditions (e.g., temperature and pressure). For example, in a variant of the maceration method described in U.S. Patent No. 2012 / 192880, the slurry is heated to 100 degrees Celsius or higher.

[0042] The liquid phase collected during filtration of the slurry represents the primary product of the maceration process and tends to be highly diluted and low in non-polar tobacco flavor species. Furthermore, the liquid phase typically contains little or no nicotine. Therefore, the liquid extract obtained by maceration generally needs to be supplemented with additional ingredients, such as nicotine salts and glycerin, before it can be used in vaporizable liquid formulations.

[0043] An alternative process is known in which tobacco material is essentially boiled in water for several hours or even days to form a vapor phase, and the distillate obtained by condensation of the vapor phase is continuously collected in a container. Over time, an oily, waxy layer containing a high proportion of non-polar compounds builds up on the surface of the distillate.

[0044] Meanwhile, a waxy layer accumulates, and the aqueous portion containing nicotine and other water-soluble compounds is recycled to the boiler. To increase the extraction yield, a non-polar co-solvent may optionally be fed to the boiler along with the aqueous portion. Meanwhile, the waxy phase is collected and ultimately forms the primary product of one such steam distillation process. This product, often referred to as "tobacco essential oil," contains a high proportion of non-polar compounds present in tobacco, such as fatty acids and neophytadiene. Tobacco essential oil obtained by one such method typically does not contain nicotine. It is also known to subject tobacco materials to extraction processes involving the use of volatile non-polar solvents. Examples of suitable solvents include cyclic or acyclic short alkanes and chlorinated solvents such as dichloromethane. In one such process, excess solvent can be evaporated by controlled heating under vacuum. This is typically done in the presence of ethanol, which has a higher boiling point than the extraction solvent, so that even traces of the extraction solvent can be detected.

[0045] One primary product of such solvent-assisted extraction processes, often referred to as "tobacco absolute," may contain traces of ethanol. This is a waxy product that contains a concentrated mixture of most non-polar compounds that can be extracted with a particular solvent, including nicotine, which is generally present in relatively high concentrations.

[0046] An alternative extraction process involves contacting tobacco material with a solvent under supercritical conditions, such as supercritical carbon dioxide. One such process, disclosed in U.S. Patent No. 2013 / 160777, relies on the principle that volatile substances within a feed material contacted with a supercritical fluid can be separated into a supercritical phase. After dissolution of any soluble materials, the supercritical fluid containing the dissolved substances can be removed, and the dissolved components of the feed material can be separated from the supercritical fluid. The primary product of a supercritical extraction process is substantially similar to the "tobacco absolute" of a solvent-assisted extraction process carried out at lower temperatures and pressures; it contains no residual solvent, typically has high levels of waxy, non-polar compounds, and generally contains nicotine, which is present in relatively high concentrations.

[0047] However, all tobacco extracts obtained by methods known in the art tend to have very low, if any, levels of compounds associated with the flavor of heated tobacco, such as furaneol.

[0048] According to the present invention, the extraction process for producing a liquid tobacco flavorant composition includes heating a tobacco starting material under specific heating conditions and collecting the generated volatile compounds. Such a step of heating the natural tobacco material may include heating the natural tobacco material in a flow of inert gas or a combination of inert gas and water or steam. Alternatively, the step of heating the natural tobacco material may include heating the natural tobacco material under a vacuum.

[0049] Thus, a liquid tobacco flavoring composition consists of a mixture of natural tobacco components derived from a tobacco starting material and extracted or formed during an extraction process, typically in combination with one or more materials other than the tobacco starting material, such as the non-aqueous extraction solvent used during the extraction process.

[0050] As described in more detail below, volatile compounds released from the starting tobacco material may be collected using condensation techniques, in which the volatile compounds are removed from the gas stream by saturating the volatile compounds in the gas stream. As an example, the inert gas stream containing the volatile compounds may be directed to a conventional shell-and-tube condenser, which may be either water-cooled or air-cooled. Because extraction is typically carried out at extraction temperatures of 100°C to 160°C, as described in more detail below, even a slight reduction in the temperature of the gas stream containing the volatile compounds by contacting the gas stream with ambient air may be sufficient to cause the volatile compounds to condense.

[0051] As used herein with respect to the present invention, the term "aerosol former" refers to a compound or mixture of compounds that, in use, facilitates the formation of an aerosol and preferably is substantially resistant to thermal decomposition at the operating temperature of the aerosol-generating article or device. Examples of suitable aerosol formers include polyhydric alcohols (such as propylene glycol, triethylene glycol, 1,3-butanediol, glycerin, etc.), esters of polyhydric alcohols (such as glycerol monoacetate, diacetate, or triacetate), and aliphatic esters of mono-, di-, or polycarboxylic acids (such as dimethyl dodecanedioate, dimethyl tetradecanedioate, etc.).

[0052] The method of the present invention utilizes a specific range of extraction temperature in combination with a specifically defined heating time, which advantageously provides an improved liquid tobacco flavor composition with a significantly improved balance of desirable and undesirable compounds. In particular, the extraction conditions of the method of the present invention provide a liquid tobacco flavor composition in which the ratio of desirable and undesirable compounds in the tobacco starting material is maximized. For example, the use of a specific combination of defined extraction temperature and time allows for minimizing the concentration of undesirable compounds such as furans, carbonyls, phenols, and TSNAs.

[0053] The method of the present invention allows for the production of liquid tobacco flavor compositions having desired levels of tobacco flavor compounds without the need to add such compounds after extraction.

[0054] In particular, the inventors have found that, in contrast to existing extraction processes such as those described above, the method according to the present invention provides a liquid tobacco flavorant composition having a significantly higher content of compounds associated with heated tobacco flavor (e.g., furaneol, etc.). These compounds are substantially absent or present in trace amounts in liquid tobacco flavorant compositions obtained by maceration processes, and typically contain little or no nicotine. These compounds are also generally absent or present in trace amounts in liquid tobacco flavorant compositions obtained using solvents, including under supercritical conditions. Similarly, tobacco essential oils obtained by distillation processes also typically contain very low, if any, content of such compounds associated with heated tobacco flavor. According to the method of the present invention, the liquid tobacco flavorant composition obtained by the extraction step is combined with a substrate to form tobacco flavored particles having an advantageously significantly improved balance of desirable and undesirable compounds.

[0055] As discussed above, the liquid tobacco flavor compositions obtained and used in the methods according to the present invention exhibit significant compositional differences compared to tobacco extracts or liquid tobacco flavor compositions obtained by existing extraction processes. As such, they can be combined with a substrate to form tobacco flavored particles with distinct composition and flavor characteristics compared to currently available tobacco flavored particles. In particular, the liquid tobacco flavor compositions obtained and used in the methods according to the present invention may be used to provide tobacco flavored particles that provide a heated tobacco taste that more closely resembles the aerosol generated by conventional cigarettes or associated with the heating of tobacco in heat-and-burn devices, compared to tobacco flavored particles made from existing liquid tobacco flavor compositions.

[0056] The method for producing the tobacco-flavored dry powder formulation of the present invention can be effectively used with all types and grades of tobacco, including burley, flue-cured, and oriental tobacco. The extraction step of the method can be easily adjusted to provide a consistent liquid tobacco flavor composition for various blends of tobacco types. The method is also suitable for various forms of tobacco starting material.

[0057] In many cases, the tobacco starting material can be heated without the need for significant pre-treatment steps. Thus, the present method can be carried out efficiently. The present method can be advantageously carried out using existing equipment and techniques that can be easily modified to carry out the steps of the present method.

[0058] In tobacco-flavored dry powder formulations according to the present invention, the weight ratio of (β-ionone + β-damascenone) to (phenol) is greater than 0.25. This can be achieved by combining the substrate with a tobacco flavorant composition having a weight ratio of (β-ionone + β-damascenone) to (phenol) greater than 0.25. Such a ratio will be higher when the amounts of the desirable flavorant compounds β-ionone and β-damascenone are high or when the amount of phenol is low.

[0059] Preferably, the weight ratio of (β-ionone + β-damascenone) to (phenol) is greater than 0.5. More preferably, the weight ratio of (β-ionone + β-damascenone) to (phenol) is greater than 1. Even more preferably, the weight ratio of (β-ionone + β-damascenone) to (phenol) is greater than 1.5. Most preferably, the weight ratio of (β-ionone + β-damascenone) to (phenol) is greater than 2.

[0060] In tobacco-flavored dry powder formulations according to the present invention, the weight ratio of (β-ionone + β-damascenone) to (phenol) is preferably about 10 or less. More preferably, the weight ratio of (β-ionone + β-damascenone) to (phenol) is 5 or less.

[0061] In some embodiments, the weight ratio of (β-ionone + β-damascenone) to (phenol) is about 0.25 to about 10, more preferably about 0.5 to about 10, even more preferably about 1 to about 10, particularly preferably about 1.5 to about 10, and most preferably about 2 to about 10. In other embodiments, the weight ratio of (β-ionone + β-damascenone) to (phenol) is about 0.25 to about 5, more preferably about 0.5 to about 5, even more preferably about 1 to about 5, particularly preferably about 1.5 to about 5, and most preferably about 2 to about 5.

[0062] Particles having a weight ratio of (β-ionone + β-damascenone) to (phenol) within the above-mentioned ranges can be obtained by combining a substrate with a tobacco flavorant composition having a weight ratio of (β-ionone + β-damascenone) to (phenol) within the above-mentioned ranges.

[0063] In tobacco-flavored dry powder formulations according to the present invention, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) may be greater than 0.2. Preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) is at least about 0.5. The above ratios will be higher if the amounts of the desirable flavor compounds β-ionone and β-damascenone are high, or if the amounts of TSNA and 2-furanmethanol are low.

[0064] More preferably, in tobacco flavored dry powder formulations according to the present invention, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) is greater than 1.

[0065] In a preferred embodiment, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) is greater than 1.5.

[0066] As an example, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) can be from about 1 to about 10, or from about 1.5 to about 6. In a particularly preferred embodiment, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) is from about 2 to about 4.

[0067] Particles having a weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) within the above ranges can be obtained by combining a substrate with a tobacco flavorant composition in which the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) is within the above ranges.

[0068] The particles of the tobacco-flavored dry powder formulation according to the present invention may further comprise other desirable compounds directly derived from natural tobacco, many of which are flavorings. By way of example, the tobacco-flavored dry powder formulation may comprise one or more of furaneol, 2,3-diethyl-5-methylpyrazine, acetic acid, vanillin, 2-ethyl-3,5-dimethylpyrazine, 2-methylbutanoic acid, 3-methylbutanoic acid, 3-methyl-2,4-nonanedione, 2-methoxyphenol, 2-phenylethanol, eugenol, and sotolone.

[0069] The particles of the dry tobacco flavored powder formulation according to the present invention contain β-ionone. The dry tobacco flavored powder formulation may contain at least 0.100 micrograms of β-ionone per gram of the dry tobacco flavored powder formulation, preferably at least 0.200 micrograms of β-ionone per gram of the dry tobacco flavored powder formulation, more preferably at least 0.300 micrograms of β-ionone per gram of the dry tobacco flavored powder formulation, and most preferably at least 0.400 micrograms of β-ionone per gram of the dry tobacco flavored powder formulation. In a preferred embodiment, the dry tobacco flavored powder formulation comprises at least 0.500 micrograms of β-ionone per gram of dry tobacco flavored powder formulation, more preferably at least 0.600 micrograms of β-ionone per gram of dry tobacco flavored powder formulation, even more preferably at least 0.700 micrograms of β-ionone per gram of tobacco flavor composition, and most preferably at least 0.800 micrograms of β-ionone per gram of dry tobacco flavored powder formulation. In particularly preferred embodiments, the dry tobacco flavored powder formulation comprises at least 0.9 micrograms of β-ionone per gram of dry tobacco flavored powder formulation, preferably at least 1.00 micrograms of β-ionone per gram of dry tobacco flavored powder formulation, more preferably at least 1.10 micrograms of β-ionone per gram of dry tobacco flavored powder formulation, even more preferably at least 1.20 micrograms of β-ionone per gram of dry tobacco flavored powder formulation, and most preferably at least 1.30 micrograms of β-ionone per gram of dry tobacco flavored powder formulation.

[0070] The weight ratio of (β-ionone) to (phenol) in the tobacco flavored dry powder formulation according to the present invention may be at least about 0.150, such as at least about 0.200, preferably at least about 0.400, more preferably at least about 0.600, and most preferably at least about 0.800, such as at least about 1.200.

[0071] Particles having a weight ratio of β-ionone to phenol within the above range can be obtained by combining a substrate with a tobacco flavorant composition having a weight ratio of β-ionone to phenol within the above range.

[0072] The weight ratio of (β-ionone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavored dry powder formulation according to the present invention may be at least about 0.300, such as at least about 0.500, preferably at least about 0.750, more preferably at least about 1.00, and most preferably at least about 1.20, such as at least about 1.80.

[0073] Particles having a weight ratio of (β-ionone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) within the above range can be obtained by combining a substrate with a tobacco flavorant composition having a weight ratio of (β-ionone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600) within the above range.

[0074] The particles of the tobacco-flavored dry powder formulation comprise β-damascenone. The tobacco-flavored dry powder formulation may comprise at least 0.100 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, preferably at least 0.350 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, more preferably at least 0.600 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, and most preferably at least 0.850 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation. In a preferred embodiment, the tobacco-flavored dry powder formulation comprises at least 1.10 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, more preferably at least 1.35 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, even more preferably at least 1.60 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, and most preferably at least 1.85 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation. In particularly preferred embodiments, the tobacco-flavored dry powder formulation comprises at least 2.10 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, preferably at least 2.35 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, more preferably at least 2.60 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, even more preferably at least 2.75 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation, and most preferably at least 2.90 micrograms of β-damascenone per gram of tobacco-flavored dry powder formulation.

[0075] In some embodiments, the tobacco flavoring composition to be combined with the substrate to form particles of the tobacco-flavored dry powder formulation according to the present invention may include a non-aqueous solvent. This may be the case, for example, when the non-aqueous solvent is used during an extraction process to collect volatile compounds released upon heating of the tobacco starting material. The non-aqueous solvent may also be an aerosol former. Thus, the tobacco-flavored powder formulation according to the present invention may include a non-aqueous solvent, preferably a non-aqueous solvent that is an aerosol former.

[0076] In these embodiments, the non-aqueous solvent may be one or more of glycerin, propylene glycol, triacetin, and 1,3-propanediol.

[0077] In preferred embodiments, the tobacco-flavored dry powder formulation contains less than 5 weight percent of non-aqueous solvent. More preferably, the tobacco-flavored dry powder formulation contains less than 3 weight percent of non-aqueous solvent. Even more preferably, the tobacco-flavored dry powder formulation contains less than 1 weight percent of non-aqueous solvent. In some particularly preferred embodiments, the tobacco-flavored dry powder formulation is substantially free of non-aqueous solvent.

[0078] In some embodiments, the tobacco flavored dry powder formulation may further comprise one or more water-soluble organic acids. As used herein in connection with the present invention, the term "water-soluble organic acid" refers to an organic acid having a water solubility of about 500 mg / ml or greater at 20 degrees Celsius.

[0079] Without wishing to be bound by theory, it is understood that a certain amount of water-soluble organic acid may be extracted from the starting tobacco material and end up in the flavor composition that is combined with the substrate to form the flavor powder particles.

[0080] In some embodiments, the water-soluble organic acid is acetic acid.

[0081] Typically, the particles of the tobacco flavored dry powder formulation according to the present invention may comprise at least about 0.001 weight percent nicotine, based on the weight of the tobacco flavored dry powder formulation.

[0082] The particles of the tobacco-flavored dry powder formulation according to the present invention preferably contain about 5 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation, and more preferably about 3 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation.

[0083] In a preferred embodiment, the particles of the tobacco-flavored dry powder formulation according to the present invention comprise about 3 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation, more preferably about 2.5 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation, and even more preferably about 2 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation.

[0084] In particularly preferred embodiments, the particles of the tobacco-flavored dry powder formulation according to the present invention comprise about 1.5 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation, more preferably about 1 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation, and even more preferably about 0.5 weight percent or less of nicotine based on the weight of the tobacco-flavored dry powder formulation.

[0085] In some embodiments, the particles of the tobacco-flavored dry powder formulation according to the present invention comprise at least about 0.01 weight percent nicotine based on the weight of the tobacco-flavored dry powder formulation, or at least about 0.02 weight percent nicotine based on the weight of the tobacco-flavored dry powder formulation, or at least about 0.05 weight percent nicotine based on the weight of the tobacco-flavored dry powder formulation. For example, the particles of the tobacco-flavored dry powder formulation according to the present invention comprise at least about 0.06 weight percent, or 0.07 weight percent, or 0.08 weight percent, or 0.09 weight percent, or 0.1 weight percent nicotine based on the weight of the tobacco-flavored dry powder formulation.

[0086] In some embodiments, the liquid tobacco flavor composition may be subjected to an additional extraction step, such as by a liquid-liquid extraction process to selectively remove nicotine or other alkaloids, or both, from the liquid tobacco flavor composition (denicotinization). This advantageously allows for control of the nicotine level in the particles of the tobacco-flavored dry powder formulation according to the present invention, such that the particles of the tobacco-flavored dry powder formulation contain less than about 1 weight percent nicotine, based on the weight of the tobacco-flavored dry powder formulation. Processes and conditions for achieving denicotinization of liquid tobacco extracts are known to those skilled in the art.

[0087] In other embodiments, the tobacco starting material may be subjected to a primary denicotinization process. Denicotinization of tobacco is a known process and is described in US 200855 A and US 3110315 A.

[0088] In further embodiments, the tobacco starting material may have a low nicotine content. Examples of low nicotine tobacco starting materials are described in US2017 / 0166913, US2017 / 0145432, and AU2015 / 202209. The weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco-flavored dry powder formulation is at least about 5x10 -4Preferably, the weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco flavored dry powder formulation is at least about 8x10 -4 More preferably, the weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco flavored dry powder formulation is at least about 1 x 10 -3 It is even more preferred that:

[0089] The weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine)*100) to (nicotine) in the tobacco-flavored dry powder formulation is approximately 9x10 -3 Preferably, the weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco-flavored dry powder formulation is about 5 x 10 -3 More preferably, it is:

[0090] In some embodiments, the weight ratio of (Furaneol+(2,3-diethyl-5-methylpyrazine)*100) to (nicotine) in the tobacco flavored dry powder formulation is about 5×10 -4 ~Approx. 9×10 -3 The weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco-flavored dry powder formulation is approximately 8 × 10 -4 ~Approx. 9×10 -3 More preferably, the weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco-flavored dry powder formulation is about 1 x 10 -3 ~approx. 9x10 -3 It is even more preferred that:

[0091] In another embodiment, the weight ratio of (Furaneol+(2,3-diethyl-5-methylpyrazine)*100) to (nicotine) in the tobacco flavored dry powder formulation is about 5x10 -4 ~about 5x10 -3The weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco-flavored dry powder formulation is about 8 x 10 -4 ~about 5x10 -3 More preferably, the weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco-flavored dry powder formulation is about 1 x 10 -3 ~about 5x10 -3 It is even more preferred that the particle having a weight ratio of (furaneol+(2,3-diethyl-5-methylpyrazine)*100)) to (nicotine) within the above-mentioned range can be obtained by combining a substrate with a tobacco flavoring composition having a weight ratio of (furaneol+(2,3-diethyl-5-methylpyrazine)*100)) to (nicotine) within the above-mentioned range.

[0092] The above-described dry tobacco flavored powder formulations may be made by a method that includes a first step of preparing a tobacco starting material, which is preferably a natural tobacco material.

[0093] As will be explained in detail below, by controlling the combination of extraction temperature and time, the composition of the liquid tobacco flavorant composition can be tailored according to the desired characteristics of the dry tobacco flavored powder formulation. In particular, the ratio of specific tobacco compounds within the dry tobacco flavored powder formulation can be tailored to some extent through the selection of extraction parameters to maximize the ratio of desirable to undesirable tobacco compounds in the liquid tobacco flavorant composition resulting from the extraction step of the present method.

[0094] The method includes a second step of heating the tobacco starting material at an extraction temperature of 100°C to 160°C for at least 90 minutes. Below this range, insufficient levels of certain flavor compounds are released from the tobacco starting material, causing the resulting liquid tobacco extract to lack desired 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 may be released. Generally, upon heating of the natural tobacco material, any moisture present in the natural tobacco material is also released along with volatile species in the form of vapor.

[0095] 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, and more preferably at least about 125 degrees Celsius.

[0096] Preferably, the extraction temperature is about 150 degrees Celsius or less, more preferably about 145 degrees Celsius or less, more preferably about 140 degrees Celsius or less, and most preferably about 135 degrees Celsius or less.

[0097] For example, the extraction temperature may be from about 110° C. to about 150° C., or from about 120° C. to about 140° C., or from about 125° C. to about 135° C., or about 130° C. An extraction temperature of about 130° C. has been found to provide a particularly optimized ratio of desirable to undesirable compounds in the liquid tobacco flavor composition.

[0098] The extraction temperature can be from about 110 degrees Celsius to about 130 degrees Celsius, or from about 115 degrees Celsius to about 125 degrees Celsius, or about 120 degrees Celsius.

[0099] The extraction temperature may be from about 125 degrees Celsius to about 155 degrees Celsius, more preferably from about 135 degrees Celsius to about 145 degrees Celsius, or about 140 degrees Celsius.

[0100] The tobacco starting material is heated at the extraction temperature for at least about 30 minutes, or at least 60 minutes, or at least about 90 minutes, and more preferably at least about 120 minutes, a period of extraction long enough to efficiently extract the desired tobacco flavor compounds and provide a liquid tobacco flavorant composition that can be combined with a substrate to produce a dry tobacco flavored powder formulation having the desired flavor characteristics.

[0101] The tobacco starting material is heated at the extraction temperature for preferably not more than about 270 minutes, more preferably not more than about 180 minutes.

[0102] For example, the tobacco starting material may be heated for about 90 minutes to about 270 minutes, or about 120 minutes to about 180 minutes.

[0103] The heating times set forth above correspond to the duration of time that the tobacco starting material is heated at the extraction temperature, and do not include the time it takes to raise the temperature of the tobacco starting material to the extraction temperature.

[0104] The extraction temperature and heating time may be selected within the ranges defined above depending on factors such as the type of tobacco, other possible components of the tobacco starting material, the desired composition of the liquid tobacco extract, etc. Optionally, the extraction temperature and heating time may be selected within the ranges defined above depending on the desired level of nicotine in the dry tobacco flavored powder formulation.

[0105] For a particular tobacco compound, the variation in the release level of the compound with extraction temperature during the extraction process can be readily determined for any given tobacco starting material.

[0106] As an example, it has been found that the desired concentrations of desirable tobacco flavor compounds, such as β-damascenone and β-ionone, released from tobacco materials increase with increasing extraction temperature up to a certain peak extraction temperature, after which these concentrations begin to decrease. The peak extraction temperature for such flavor compounds is typically within the range of 100° C. to 160° C., so that the extraction methods of the present invention can effectively optimize the levels of the desired flavor compounds.

[0107] It has been found that the levels of undesirable tobacco compounds increase slowly with increasing extraction temperature up to a threshold temperature, above which a rapid increase is observed. This applies, for example, to the concentrations of phenolic compounds, TSNAs, and pyrazines, and, in the case of bright tobacco, to the concentrations of furans and formaldehyde. In many cases, the threshold temperature is within the range of 100°C to 160°C, and therefore the levels of undesirable compounds can be effectively controlled by adjusting the extraction conditions in the production method of the present invention.

[0108] In some embodiments, the extraction temperature is selected to provide a weight ratio of (β-ionone+β-damascenone) to (phenol) in the tobacco flavorant composition of at least about 0.25.

[0109] Preferably, the extraction temperature, or extraction time, or both the extraction temperature and extraction time, are selected to provide a weight ratio of (β-ionone + β-damascenone) to (phenol) in the liquid tobacco flavor composition of at least about 0.5, even more preferably at least 1, and most preferably at least about 1.5. More preferably, the extraction temperature, or extraction time, or both the extraction temperature and extraction time, are selected to provide a weight ratio of (β-ionone + β-damascenone) to (phenol) in the liquid tobacco flavor composition of at least about 2, most preferably a weight ratio of (β-ionone + β-damascenone) to (phenol) of about 2 to about 10, or about 2 to about 5.

[0110] β-damascenone and β-ionone are desirable compounds associated with tobacco flavor. It has also been found that the amount of β-damascenone and β-ionone released from tobacco materials increases as the extraction temperature increases up to a certain peak extraction temperature, after which the levels begin to decrease. The peak extraction temperature for these flavor compounds is typically within the range of 100°C to 160°C, allowing for effective adjustment and control of the levels of the desired flavor compounds in dry powder formulations during manufacturing.

[0111] In some embodiments, the extraction temperature, or extraction time, or both the extraction temperature and extraction time, are selected to provide a weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavor composition of at least about 1.5. This ratio will be higher when the amounts of the desirable flavor compounds β-ionone and β-damascenone are high, or when the amounts of TSNA and 2-furanmethanol are low.

[0112] The weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavoring composition can be at least about 0.2, such as at least about 0.5.

[0113] In some embodiments, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavor composition is at least about 1. Preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavor composition is at least about 1.5. More preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavor composition is at least about 2. Even more preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavor composition is at least about 2.5.

[0114] Preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavor composition is about 10 or less. More preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavor composition is about 6 or less. Even more preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavoring composition is about 4 or less.

[0115] In a preferred embodiment, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavorant composition is from about 1.5 to about 10, more preferably from about 2 to about 10, and even more preferably from about 2.5 to about 10. In another embodiment, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavoring composition is from about 1.5 to about 6, more preferably from about 2 to about 6, and even more preferably from about 2.5 to about 6. In a further embodiment, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavoring composition is from about 1.5 to about 4, more preferably from about 2 to about 4, and even more preferably from about 2.5 to about 4.

[0116] Preferably, the extraction temperature, or the extraction time, or both the extraction temperature and the extraction time, is at least about 5x10 -4 More preferably, the extraction temperature, or the extraction time, or both the extraction temperature and the extraction time, are selected to provide a weight ratio of (furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) of at least about 8x10 in the tobacco flavorant composition. -4 , and even more preferably at least 1x10 -3 The extraction temperature, or the extraction time, or both the extraction temperature and the extraction time, are selected to provide a weight ratio of (furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) of about 9x10 in the tobacco flavoring composition. -3 Less than or equal to 5x10 -3Preferably, the extraction temperature, or the extraction time, or both the extraction temperature and the extraction time, are selected to provide a weight ratio of about 8x10 furaneol to nicotine in the tobacco flavorant composition. -4 ~approx. 9x10 -3 , or about 8x10 -4 ~about 5x10 -3 , or about 1x10 -3 ~approx. 9x10 -3 , or about 1x10 -3 ~about 5x10 -3 The compound is selected to provide a weight ratio of (Furaneol + (2,3-diethyl-5-methylpyrazine) * 100)) to (nicotine).

[0117] The heating step is preferably carried out in an inert atmosphere. A stream of inert gas, such as nitrogen, is preferably passed through the tobacco starting material during the heating step. Alternatively, the inert gas may be used in combination with water or steam. Volatile tobacco compounds are released into the inert gas stream, or into a stream of inert gas and water or steam, during the heating step, so that the inert gas acts as a carrier for the volatile components.

[0118] The inert gas stream serves to carry vapors generated by evaporation of the moisture content of the natural tobacco material and volatile species (including, inter alia, nicotine, or flavor-related compounds, or both) from the extraction equipment.

[0119] Furthermore, the use of a flow of inert gas (such as nitrogen) under a slight overpressure within the extraction equipment has the advantage of preventing the presence of oxygen within the extraction equipment. This can also be achieved by heating the natural tobacco material under vacuum. This advantage is desirable in that it prevents any risk of combustion (even partial combustion) of the natural tobacco material during the heating process. Uncontrolled combustion of the natural tobacco material would clearly be undesirable, as it would pose a major safety risk within the manufacturing environment. However, the inventors have found that even limited and partial combustion of the natural tobacco material may lead to a deterioration in the quality of the tobacco extract obtainable by the present method, which would be undesirable.

[0120] Without wishing to be bound by theory, it is understood that preventing the combustion of the natural tobacco material also prevents the formation of any undesirable combustion by-products. Furthermore, when conditions that would promote the combustion of the natural tobacco material are prevented, the natural tobacco material is effectively heated under conditions that mimic, to some extent, the conditions under which tobacco-containing substrates (e.g., homogenized tobacco material) are typically heated in "heat-and-not-burn" articles. As a result, selective extraction of flavor-imparting volatile species that are responsible for the taste consumers associate with heated tobacco is advantageously favored.

[0121] Therefore, by performing the heating step in an inert atmosphere, extraction efficiency, product quality, and manufacturing safety are advantageously enhanced.

[0122] The inert gas flow rate may be optimized based on the size and geometry of the extraction chamber, and a relatively high flow rate of inert gas may advantageously further improve the efficiency of extraction from the tobacco starting material.

[0123] The addition of water or steam to tobacco during extraction has been found to increase the yield of extracted components, however, adding too much water or steam can lead to processing difficulties such as stickiness of the tobacco material.

[0124] Optionally, the heating step may be carried out under vacuum.

[0125] Suitable heating methods for carrying out heating of the tobacco starting material are known to those skilled in the art and include, but are not limited to, dry distillation, steam distillation, vacuum distillation, flash distillation, and thin film steam distillation.

[0126] The liquid tobacco flavor composition may be prepared from a tobacco starting material consisting of a single type of natural tobacco. Alternatively, the tobacco starting material may comprise a blend of two or more types of natural tobacco. The ratio of different tobacco types may be adapted depending on the desired flavor characteristics of the tobacco-flavored dry powder formulation produced from the liquid tobacco flavor composition. For example, if it is desired to provide a relatively high level of nicotine, the proportion of burley tobacco may be increased.

[0127] If it is desired to make a liquid tobacco flavor composition from a combination of two or more different types of tobacco, the tobacco types may be heated separately 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.

[0128] The tobacco starting material may be a solid tobacco material such as powder, leaf scraps or pieces, or intact leaves. Alternatively, the tobacco starting material may be a liquid tobacco material such as a dough, gel, slurry, or suspension.

[0129] The tobacco starting material may be derived from any suitable tobacco material, including, but not limited to, tobacco leaf, tobacco stems, reconstituted tobacco, cast tobacco, extruded tobacco, or tobacco-derived pellets.

[0130] In the process of preparing the tobacco starting material, the tobacco is preferably milled or chopped to reduce the size of the tobacco particles within the tobacco starting material, which may advantageously improve the uniformity of heating and efficiency of extraction of the tobacco starting material.

[0131] The tobacco starting material may optionally be dried prior to the heating step to reduce the moisture content of the tobacco starting material. Drying 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 moisture content of the tobacco starting material.

[0132] In certain embodiments of the present invention, the step of preparing a tobacco starting material may include impregnating the tobacco starting material with an aerosol former. If this impregnation of the tobacco starting material is performed before the heating step, it can advantageously increase the amount of certain desirable tobacco compounds released from the tobacco starting material upon heating. For example, impregnation of the tobacco starting material with glycerin has been found to advantageously increase the amount of nicotine extracted from the tobacco starting material. In another example, impregnation of the tobacco starting material with a polar aerosol former, such as a mixture of polyethylene glycol and vegetable glycerin or triacetin, has been found to advantageously increase the amount of flavor compounds extracted from the tobacco starting material.

[0133] Optionally, the tobacco starting material may be enzymatically digested prior to the heating step, which has been found to provide a significant increase in the yield of certain flavor compounds from the tobacco starting material.

[0134] The tobacco starting material may optionally be analyzed prior to the heating step to determine its composition, e.g., alkaloid and reducing sugar content. This information regarding composition may be usefully used to select an appropriate extraction temperature.

[0135] In preparing the natural tobacco material, the tobacco is preferably not subjected to any treatment adapted to change the pH of the tobacco. In particular, in preparing the natural tobacco material, the tobacco is not subjected to any treatment adapted to significantly increase the pH of the tobacco. For example, the natural tobacco material is not contacted with an aqueous solution containing an alkali or alkaline earth metal salt. 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 may be perceived by consumers. Furthermore, the inventors have discovered that subjecting the natural tobacco material to a treatment adapted to increase the pH of the tobacco, such as alkali treatment, before heating the tobacco material as part of the extraction process leads to a decrease in the concentration of desired heated tobacco flavor compounds in the liquid tobacco extract. As an example, it has been found that not subjecting the natural tobacco material to alkali treatment is associated with a significantly increased weight ratio of (β-ionone + β-damascenone) to (phenol) in the liquid tobacco extract compared to the corresponding alkali-treated natural tobacco material.

[0136] During heating of the tobacco starting material, the volatile compounds released from the tobacco starting material are collected using any suitable technique. As described above, when the tobacco starting material is heated in a flow of inert gas, the volatile compounds are collected from the flow of inert gas. Different collection methods will be known to those skilled in the art. In considering the collection process, heating the natural tobacco material in a flow of inert gas, or a flow containing inert gas and water or steam, has the additional advantage that the flow of inert gas containing the volatile compounds can be more easily directed into a vessel containing an extraction solvent, such as a non-aqueous extraction liquid solvent.

[0137] The step of collecting the volatile compounds is preferably carried out using a condensation technique in which the volatile compounds are condensed and the condensate is collected.

[0138] In some embodiments, the resulting condensate is added to a liquid aerosol former, preferably propylene glycol (PG).

[0139] The addition of a liquid aerosol former, particularly PG, may advantageously prevent condensed volatile compounds from separating into two phases or forming an emulsion, as some tobacco components tend to do. Without wishing to be bound by theory, the inventors have observed that the solubility of a tobacco component in an aqueous extract (i.e., the aqueous fraction of a liquid naturally occurring tobacco extract) depends primarily on its polarity, its concentration, and the pH of the aqueous extract, which may vary depending on the tobacco type. As a result, if the amount of aerosol former is insufficient, an oily layer tends to form on the surface of the liquid tobacco flavor composition. Such oily material may aggregate in different locations on the equipment used to carry out the extraction process. The addition of a liquid aerosol former, such as PG, helps prevent the formation of such a layer and favors the homogenization of the liquid tobacco flavor composition.

[0140] Furthermore, liquid aerosol formers are advantageous for capturing flavor-relevant compounds regardless of their polarity and volatility. The use of PG as an aerosol former for the condensation and collection process has the added benefit that PG exerts antimicrobial activity by reducing the water activity of aqueous solutions. Therefore, by adjusting the PG content in a liquid tobacco flavoring composition, it is possible to ensure that the composition is substantially free of microbial activity.

[0141] Condensation techniques are techniques for removing volatile compounds from gas streams by saturating them. Condensation, cooling, and cryogenic systems are typically used with gas streams containing only volatile organic compounds. Saturation (dew point temperature) occurs when the partial pressure of the volatile compound equals its vapor pressure. Once saturation is achieved, separation by condensation occurs by either increasing the system pressure at a constant temperature (known as compression condensation) or decreasing the temperature at a constant temperature (known as cooling condensation).

[0142] In the method according to the invention, the step of collecting the volatile compounds is preferably carried out using a cooling condensation technique. This can be achieved either by direct contact of the gas stream containing the volatile compounds with a cooling liquid. Alternatively, this can be achieved by indirect contact via a heat exchanger between the gas stream containing the volatile compounds and a cooling medium. In direct contact applications, a cryogenic gas such as liquid nitrogen may be injected into the gas stream. Direct cooling condensation may require an additional separation stage, so indirect cooling condensation may be preferred.

[0143] By way of example, in the method according to the invention, condensation of volatile compounds may be carried out using any suitable device, for example in a cooling column.

[0144] However, because the extraction process is typically carried out at temperatures of about 130 degrees Celsius to about 160 degrees Celsius, gentle cooling of the gas stream and air at room temperature is generally sufficient to cause condensation of the extracted volatile compounds.

[0145] In an alternative embodiment, the step of collecting the volatile compounds may use an absorption technique to trap the volatile compounds in a liquid solvent. For example, an inert gas stream containing the volatile compounds may be directed into a container of liquid solvent. The liquid solvent may be an aerosol former such as triacetin, glycerin, polyethylene glycol, or a combination thereof. Preferably, the liquid solvent is maintained at a temperature below 0 degrees Celsius to optimize the transfer of the volatile compounds into the liquid solvent.

[0146] As a further alternative, the step of collecting the volatile compounds can be carried out using adsorption techniques in which the volatile compounds are adsorbed onto the surface of a solid adsorbent material, such as activated carbon. The adsorbed compounds can then be transferred into a liquid solvent.

[0147] In the method of the present invention, the next step is to form a liquid tobacco flavorant composition from the collected volatile compounds. The nature of this step may depend on the collection method. The "collected volatile compounds" may be in the form of a solution of tobacco-derived volatile compounds in a liquid solvent or carrier.

[0148] When the volatile compounds are collected by condensation, the step of forming the liquid tobacco flavorant composition may include adding the condensate to a liquid vehicle, such as an aerosol former.

[0149] Alternatively, if the volatile compounds are collected by adsorption in a liquid solvent, the step of forming the liquid tobacco flavorant composition preferably includes drying the solution of the volatile compounds in the liquid solvent to concentrate the solution. This may be performed, for example, to reach a desired concentration of flavor compounds. Drying may be performed using any suitable means, including, but not limited to, desiccation, molecular sieving, freeze-drying, phase separation, distillation, membrane permeation, controlled water crystallization and filtration, reverse hygroscopicity, ultracentrifugation, liquid chromatography, reverse osmosis, or chemical drying.

[0150] In a preferred embodiment, the solution of the volatile compound in the liquid solvent is concentrated by drying.

[0151] Optionally, the step of forming the liquid tobacco flavorant composition comprises a filtering step.

[0152] Optionally, the step of forming the liquid tobacco flavorant composition includes a blending step in which extracts derived from different tobacco starting materials are combined.

[0153] Optionally, the step of forming the liquid tobacco flavorant composition includes adding one or more additives, such as an organic acid, to the solution of volatile compounds, although in many cases the liquid tobacco flavorant composition is suitable for use without additives.

[0154] In the method according to the present invention, the tobacco flavorant composition is combined with a substrate to form a plurality of particles of the dry tobacco flavored formulation.

[0155] The substrate may comprise one or more of gums such as gum arabic, guar seed meal, locust bean meal, khataya, ghatti, tragacanth, xanthan, etc., starch, hydrolyzed starch such as maltodextrin and corn syrup solids or glucose syrup, chemically modified starch, carboxymethylcellulose, sugars such as monosaccharides, disaccharides, or polysaccharides. Examples of suitable sugars include, but are not limited to, lactose, sucrose, raffinose, trehalose, fructose, dextrose, glucose, maltose, mannitol, or combinations thereof. Particularly preferred sugars include trehalose or mannitol.

[0156] To improve the oxidative stability of tobacco extracts, simple sugars and sugar alcohols such as sucrose, lactose, and glucose, or sorbitol, can be blended with chemically modified starch or gum arabic. Hydrolyzed starch has little retention of lipophilic volatiles but is very suitable as a carrier for hydrophilic volatiles. Emulsified starch has good lipophilic properties and provides emulsifying properties and excellent volatile retention during spray drying, but is poor at protecting tobacco extract flavorants from oxidation. Gum arabic is an excellent encapsulating material and a very good emulsifier, providing good retention of volatiles during the drying process of the resulting tobacco-flavored powder. Particularly preferred are substrates with good encapsulating properties, such as maltodextrin and cyclomaltodextrin.

[0157] In one embodiment, the process of combining the substrate and the tobacco flavorant composition to form tobacco flavored particles includes a first step of forming a mixture of the substrate and the liquid tobacco flavorant composition, a second step of freezing the mixture, a third step of drying the frozen mixture, and a fourth step of grinding the dried mixture to form the tobacco flavored particles.

[0158] In another embodiment, combining the substrate and the tobacco flavorant composition to form tobacco flavored particles comprises forming a mixture of the substrate and the liquid tobacco flavorant composition and spray drying the mixture to form the tobacco flavored particles.

[0159] The particles of the above-described dry tobacco flavored powder formulations may find use in a powder system comprising an additional plurality of particles. In some embodiments, a powder system according to the present invention may comprise a first plurality of particles obtained as described above, or by the above-described method, or both, having a particle size of at least about 20 micrometers in combination with a second plurality of particles comprising nicotine, having a particle size of about 10 micrometers or less.

[0160] Without wishing to be bound by theory, the larger tobacco flavor-bearing particles are adapted for deposition in the consumer's mouth, while the smaller nicotine-containing particles are adapted to reach the consumer's lungs upon inhalation.

[0161] In a preferred embodiment, the particles of the second plurality of particles comprise nicotine, a sugar, or an amino acid, or both. Preferably, the particles of the second plurality of particles comprise nicotine, a sugar, and an amino acid. As used herein in connection with the present invention, the term "amino acid" refers to a single amino acid moiety, unmodified or modified, with unmodified being preferred.

[0162] In another embodiment, a powder system according to the present invention comprises a first plurality of tobacco flavored particles having a particle size of at least about 20 micrometers and a second plurality of particles having a particle size of less than about 20 micrometers, wherein a first weight ratio of (β-ionone + β-damascenone) to (phenol) in the first plurality of tobacco flavored particles is greater than 0.25.

[0163] Preferably, the weight ratio of (β-ionone+β-damascenone) to (phenol) in the first plurality of tobacco flavored particles is greater than 0.5.

[0164] Preferably, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the first plurality of tobacco flavored particles is greater than 1.5.

[0165] Additionally, the first plurality of tobacco flavored particles may include one or more of furaneol, 2,3-diethyl-5-methylpyrazine, acetic acid, vanillin, 2-ethyl-3,5-dimethylpyrazine, 2-methylbutanoic acid, 3-methylbutanoic acid, 3-methyl-2,4-nonanedione, 2-methoxyphenol, 2-phenylethanol, eugenol, and sotolone.

[0166] The powder system according to the present invention may comprise at least about 5 weight percent of the first particles. Preferably, the powder system comprises at least about 10 weight percent of the first particles. More preferably, the powder system comprises at least about 15 weight percent of the first particles.

[0167] The powder system may include about 50 weight percent or less of the first particles. Preferably, the powder system includes about 45 weight percent or less of the first particles. More preferably, the powder system includes about 25 weight percent or less of the first particles.

[0168] In some embodiments, the powder system comprises about 5 weight percent to about 50 weight percent of the first particles, more preferably about 10 weight percent to about 50 weight percent, and even more preferably about 15 weight percent to about 50 weight percent of the first particles. In other embodiments, the powder system comprises about 5 weight percent to about 45 weight percent of the first particles, more preferably about 10 weight percent to about 45 weight percent, and even more preferably about 15 weight percent to about 45 weight percent of the first particles. In further embodiments, the powder system comprises about 5 weight percent to about 25 weight percent of the first particles, more preferably about 10 weight percent to about 25 weight percent, and even more preferably about 15 weight percent to about 25 weight percent of the first particles.

[0169] The powder system may include at least about 50 weight percent of the second particles. Preferably, the powder system includes at least about 65 weight percent of the second particles. More preferably, the powder system includes at least about 75 weight percent of the second particles.

[0170] The powder system can include up to about 95 weight percent of the second particles. Preferably, the powder system includes up to about 90 weight percent of the second particles. More preferably, the powder system includes up to about 85 weight percent of the second particles.

[0171] In some embodiments, the powder system comprises about 50 weight percent to about 95 weight percent of the second particles, more preferably about 65 weight percent to about 95 weight percent, and even more preferably about 75 weight percent to about 95 weight percent of the second particles. In other embodiments, the powder system comprises about 50 weight percent to about 90 weight percent of the second particles, more preferably about 65 weight percent to about 90 weight percent, and even more preferably about 75 weight percent to about 90 weight percent of the second particles. In further embodiments, the powder system comprises about 50 weight percent to about 85 weight percent of the second particles, more preferably about 65 weight percent to about 85 weight percent, and even more preferably about 75 weight percent to about 85 weight percent of the second particles.

[0172] In powder systems according to the present invention, the weight ratio of the second plurality of particles to the first plurality of particles can be at least about 1:1, preferably at least 2:1, and more preferably about 3:1.

[0173] In a powder system according to the present invention, the weight ratio of the second plurality of particles to the first plurality of particles can be about 10:1 or less, preferably 8:1 or less, more preferably 6:1 or less, and even more preferably 5:1 or less.

[0174] In some embodiments, the weight ratio of the second plurality of particles to the first plurality of particles is preferably about 1:1 to about 8:1, more preferably about 2:1 to about 8:1, and even more preferably about 3:1 to about 8:1. In another embodiment, the weight ratio of the second plurality of particles to the first plurality of particles is preferably about 1:1 to about 6:1, more preferably about 2:1 to about 6:1, and even more preferably about 3:1 to about 6:1. In a further embodiment, the weight ratio of the second plurality of particles to the first plurality of particles is preferably about 1:1 to about 5:1, more preferably about 2:1 to about 5:1, and even more preferably about 3:1 to about 5:1. As an example, the weight ratio of the second plurality of particles to the first plurality of particles can be about 4:1.

[0175] Preferably, the first plurality of particles and the second plurality of particles form at least about 90 weight percent, or at least about 95 weight percent, or at least about 99 weight percent, or 100 weight percent of the total weight of the powder system.

[0176] The first plurality of particles may have a particle size of at least about 20 micrometers, preferably at least about 50 micrometers, more preferably at least about 75 micrometers, and even more preferably at least about 100 micrometers. The first plurality of particles preferably has a particle size of no greater than about 200 micrometers. More preferably, the first plurality of particles has a particle size of no greater than about 150 micrometers.

[0177] The first plurality of particles preferably has a particle size of about 20 micrometers to about 200 micrometers, more preferably about 50 micrometers to about 200 micrometers, and even more preferably about 75 micrometers to about 200 micrometers. In other embodiments, the first plurality of particles has a particle size of about 20 micrometers to about 150 micrometers, more preferably about 50 micrometers to about 150 micrometers, and even more preferably about 75 micrometers to about 150 micrometers.

[0178] The second plurality of particles may have a particle size of about 10 micrometers or less, preferably about 5 micrometers or less, and more preferably about 3 micrometers or less.

[0179] As briefly described above, the particles of the second plurality of particles preferably comprise nicotine, sugar, and an amino acid. The amino acid reduces the adhesive forces of the particles and reduces or prevents aggregation of the particles during formation or subsequent handling. The second plurality of particles can form a free-flowing material and have a stable relative particle size distribution during processing, shipping, and storage.

[0180] Useful amino acids may include leucine, alanine, valine, isoleucine, methionine, phenylalanine, tyrosine, tryptophan, or combinations thereof. One preferred amino acid is leucine or a leucine isomer (such as L-leucine). An example of a preferred peptide is trileucine.

[0181] The particles may contain sugars. Sugars refer to simple sugars, monosaccharides, disaccharides, and polysaccharides. Non-limiting examples of suitable sugars include lactose, sucrose, raffinose, trehalose, fructose, dextrose, glucose, maltose, mannitol, or a combination thereof. Preferred sugars include trehalose or mannitol.

[0182] The second plurality of particles may contain about 30 weight percent or less nicotine. Preferably, the second plurality of particles contains about 10 weight percent or less nicotine. More preferably, the second plurality of particles contains about 7 weight percent or less nicotine. Even more preferably, the second plurality of particles contains about 6 weight percent or less nicotine.

[0183] Preferably, the second plurality of particles contains at least about 1 weight percent nicotine. More preferably, the second plurality of particles contains at least about 2 weight percent nicotine. Even more preferably, the second plurality of particles contains at least about 3 weight percent nicotine. Most preferably, the second plurality of particles contains at least about 4 weight percent nicotine.

[0184] In some embodiments, the second plurality of particles comprises between about 1 weight percent nicotine and about 10 weight percent nicotine, preferably between about 2 weight percent nicotine and about 10 weight percent nicotine, more preferably between about 3 weight percent nicotine and about 10 weight percent nicotine, and even more preferably between about 4 weight percent nicotine and about 10 weight percent nicotine.

[0185] In other embodiments, the second plurality of particles comprises between about 1 weight percent nicotine and about 30 weight percent nicotine, preferably between about 2 weight percent nicotine and about 25 weight percent nicotine, more preferably between about 3 weight percent nicotine and about 20 weight percent nicotine, and even more preferably between about 4 weight percent nicotine and about 15 weight percent nicotine.

[0186] In other embodiments, the second plurality of particles comprises between about 1 weight percent nicotine and about 7 weight percent nicotine, preferably between about 2 weight percent nicotine and about 7 weight percent nicotine, more preferably between about 3 weight percent nicotine and about 7 weight percent nicotine, and even more preferably between about 4 weight percent nicotine and about 7 weight percent nicotine.

[0187] In a further embodiment, the second plurality of particles comprises between about 1 weight percent nicotine and about 6 weight percent nicotine, preferably between about 2 weight percent nicotine and about 6 weight percent nicotine, more preferably between about 3 weight percent nicotine and about 6 weight percent nicotine, and even more preferably between about 4 weight percent nicotine and about 6 weight percent nicotine.

[0188] The nicotine in nicotine particles can be pharmaceutically acceptable free base nicotine, or nicotine salt or nicotine salt hydrate.Useful nicotine salt or nicotine salt hydrate includes, for example, nicotine pyruvate, nicotine citrate, nicotine aspartate, nicotine lactate, nicotine bitartrate, nicotine salicylate, nicotine fumarate, nicotine mono-pyruvate, nicotine glutamate or nicotine hydrochloride.The compound that combines with nicotine to form salt or salt hydrate can be selected based on its expected pharmacological effect.

[0189] The nicotine content is calculated based on the total amount of nicotine, regardless of the form of the nicotine. For example, the second plurality of particles may contain 8.4 weight percent of a nicotine salt, such as nicotine lactate, and therefore the nicotine content in the second plurality of particles is 5 weight percent.

[0190] Methods for assessing whether a powder system is a powder system according to the present invention are available to those skilled in the art. One such method involves a first step of assessing whether the powder system comprises a first plurality of particles having a particle size of at least about 20 micrometers in combination with a second plurality of particles having a particle size of less than about 20 micrometers, such as a particle size of about 10 micrometers or less. As an example, this first step may involve using laser diffraction or laser scattering to determine whether the powder system has a bimodal or multimodal size distribution and whether a particle population having a particle size of 20 micrometers or greater is present.

[0191] Additionally, one such method includes a second step of separating the plurality of particles having a size of at least about 20 micrometers from smaller particles. One such second step can involve, for example, using an impactor or sieve to separate the particles based on their size, such that particles having a particle size of at least about 20 micrometers can be grouped together.

[0192] Additionally, one such method includes a third step of analyzing the particles having a particle size of at least about 20 micrometers to verify that the weight ratio of (β-ionone + β-damascenone) to (phenol) in the first plurality of particles is greater than 0.25.

[0193] One embodiment of the present invention will now be further described, by way of example only. [Example]

[0194] Example 1 The tobacco starting material is prepared from fully cured litre 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 an extraction chamber without compression. The tobacco starting material is heated to a temperature of 130°C in the extraction chamber for three hours. During heating, a stream of nitrogen is passed through the extraction chamber at a flow rate of approximately 40 liters / minute.

[0195] Volatile compounds released from the tobacco starting material during the heating process are collected by absorption into a liquid solvent formed from propylene glycol at minus 10 degrees Celsius and agitation at 750 rpm.

[0196] Thus, the liquid tobacco flavor composition is obtained directly from the extraction process at a temperature of 130 degrees Celsius for three hours. The liquid tobacco flavor composition provides optimized levels of desirable flavor compounds such as β-damascenone and β-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-furanmethanol. The liquid tobacco flavor composition further provides levels of desirable flavor compounds such as furaneol and 2,3-diethyl-5-methylpyrazine relative to nicotine.

[0197] The propylene glycol solution with the collected volatile compounds is concentrated in a drying process to reduce the moisture level of the liquid tobacco extract to about 15 percent.

[0198] Example 2 This example provides two liquid tobacco flavor compositions, both of which are obtained directly from an extraction process at a temperature of 130 degrees Celsius for 3 hours.

[0199] Example 2a Example 2a relates to a liquid tobacco flavor composition derived from flue-cured bright tobacco material. The contents of the concentrated liquid tobacco flavor composition of Example 2a are as follows: Nicotine: 0.53% w / w Propylene glycol: 91.8% w / w Water: 6.3% w / w Balance (including flavorings detailed in Table 1 below): 1.57% w / w

[0200] Example 2b Example 2b relates to a liquid tobacco flavor composition derived from Burley tobacco material. The contents of the concentrated liquid tobacco flavor composition of Example 2b are as follows: Nicotine: 1.82% w / w Propylene glycol: 89.6% w / w Water: 5.7% w / w Balance (including flavorings detailed in Table 1 below): 2.88% w / w [Table 1]

[0201] The liquid tobacco flavor compositions of Examples 2a and 2b according to 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-furanmethanol.

[0202] Example 3 This example provides three liquid tobacco flavor compositions according to the present invention, each of which is a liquid tobacco flavor composition obtained directly from an extraction process at a temperature of 130 degrees Celsius for 3 hours.

[0203] Example 3a Example 3a relates to a liquid tobacco flavor composition derived from Orient Bright tobacco material. The liquid tobacco flavor composition of Example 3a has the following contents: Nicotine: 0.4% w / w Propylene glycol: 84% w / w Acetic acid: 1.0% w / w Water: 12.5% ​​w / w Balance (including flavorings): 2.1% w / w

[0204] Example 3b Example 3b relates to a liquid tobacco flavor composition derived from flue-cured bright tobacco material. The liquid tobacco flavor composition of Example 3b has the following contents: Nicotine: 1.2% w / w Propylene glycol: 84% w / w Acetic acid: 1.0% w / w Water: 12.5% ​​w / w Balance (including flavorings): 1.3% w / w

[0205] Example 3c Example 3c relates to a liquid tobacco flavor composition derived from Burley tobacco material. The liquid tobacco flavor composition of Example 3c has the following contents: Nicotine: 2.6% w / w Propylene glycol: 84% w / w Acetic acid: 0.5% w / w Water: 12.5% ​​w / w Balance (including flavorings): 0.4% w / w

[0206] The liquid tobacco flavor composition of Example 3 provides optimized levels of desirable flavor compounds such as β-damascenone and β-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-furanmethanol. The liquid tobacco flavor composition further provides levels of desirable flavor compounds such as furaneol and 2,3-diethyl-5-methylpyrazine relative to nicotine.

[0207] Example 4 The liquid tobacco flavor composition of Example 1 was concentrated by a drying process to reduce the moisture level of the liquid tobacco extract to about 15 percent.

[0208] Glycerin was added to the resulting concentrated liquid tobacco extract so that the liquid tobacco flavor composition ultimately contained 20 weight percent glycerin and 80 weight percent liquid tobacco extract, based on the weight of the liquid tobacco flavor composition.

[0209] Example 5 The liquid tobacco flavor compositions of Examples 1 to 4 are combined with a base material consisting of maltodextrin, with the weight ratio of the liquid tobacco flavor composition to the base material being 30:70.

[0210] More specifically, 7 grams of maltodextrin is weighed into each of the beakers, and then 3 grams of each of the liquid tobacco flavorant compositions of Examples 1-4 is weighed into the respective beakers.

[0211] The two components are stirred to obtain a homogenous dough-like mixture. The dough-like mixture is spread on a Petri dish, covered with aluminum foil, and stored in a freezer for at least two hours. The frozen dough-like mixture is then introduced into a freeze-drying chamber (freeze dryer) to dehydrate the dough-like mixture. This is a two-step process. In the first step of primary drying, the dough-like mixture is dried for approximately 12 hours to allow the ice to sublimate. In the second set of secondary drying, the dough-like mixture is dried for an additional two hours to remove unfrozen water molecules.

[0212] Before starting the drying process, the aluminum foil on top of the Petri dish is perforated to facilitate the removal of water from the dough-like mixture.

[0213] The dehydrated dough-like mixture is then transferred to an alumina mortar and ground to form tobacco-flavored particles, resulting in a tobacco-flavored dry powder formulation having a particle size distribution average of about 50 micrometers to about 60 micrometers.

[0214] Example 6 Example 6 provides particles of a tobacco-flavored dry powder formulation similar to those of Example 5. In contrast to the particles of Example 5, the weight ratio of the liquid tobacco flavor composition to the substrate in the particles of Example 6 is 50:50 (Example 6a) and 20:80 (Example 6b).

[0215] Example 7 Example 7 provides particles of a tobacco-flavored dry powder formulation similar to those of Example 5. In contrast to the particles of Example 5, the extract of Example 7 was prepared by condensation without adding propylene glycol or other solvents. Therefore, the concentration of flavor compounds in the liquid tobacco flavor composition is significantly higher, and in light of this, the weight ratio of the liquid tobacco flavor composition to the substrate in the particles of Example 7 is 10:90 (Example 7a) and 15:85 (Example 7b).

[0216] Example 8 Three tobacco starting materials are prepared from flue-cured bright tobacco material (2A), burley tobacco material (2B), and orient tobacco material (2C), respectively.

[0217] Each one of the three tobacco materials 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.

[0218] Each one of the tobacco starting materials is heated in an extraction chamber for 120 minutes to a temperature of 130 degrees Celsius. During heating, a stream of nitrogen is passed through the extraction chamber at a flow rate of 2 liters / minute.

[0219] Volatile compounds released from each tobacco starting material during the heating process are collected by absorption into a liquid solvent formed from polypropylene glycol at 0 degrees Celsius.

[0220] Liquid tobacco extracts are obtained directly from these extraction processes. Each liquid extract obtained from each of the three tobacco starting materials is then concentrated under vacuum (50 mbar) at 55 degrees Celsius until it reaches a moisture content of 12 percent ± 2 percent. [Table 2]

[0221] In all three liquid extracts according to inventions 2A, 2B, and 2C, the weight ratio of (β-ionone + β-damascenone) to (phenol) was consistently and significantly greater than 2.0. Furthermore, in all three liquid extracts according to inventions 2A, 2B, and 2C, the weight ratio of (furaneol + (2,3-diethyl-5-methylpyrazine)*100) to (nicotine) was consistently and significantly greater than 1×10 -3Furthermore, in all three liquid extracts according to Inventions 2A, 2B, and 2C, the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) is consistently and significantly greater than 3.

Claims

1. 1. A method of making a tobacco flavored powder formulation, said method comprising: preparing a tobacco starting material; heating the tobacco starting material at an extraction temperature of 100 degrees Celsius to 160 degrees Celsius for at least 90 minutes; collecting volatile compounds released from the tobacco starting material during the heating step; forming a liquid tobacco flavorant composition containing the collected volatile compounds; combining a substrate with the liquid tobacco flavorant composition to form tobacco flavored particles; In the step of preparing the tobacco starting material, the tobacco starting material is not subjected to any treatment adapted to change the pH of the tobacco; said step of combining said substrate with said liquid tobacco flavor composition to form tobacco flavored particles comprises: forming a mixture of the substrate and the liquid tobacco flavorant composition; freezing the mixture; drying the frozen mixture; and grinding the dry mixture to form the tobacco flavored particles. Alternatively, the step of combining the substrate with the liquid tobacco flavorant composition to form tobacco flavored particles comprises: forming a mixture of the substrate and the liquid tobacco flavorant composition; and spray drying the mixture to form the tobacco flavored particles. method.

2. 10. The method of claim 1, wherein the tobacco starting material is heated to an extraction temperature of 120 degrees Celsius to 140 degrees Celsius.

3. 3. The method of claim 1 or 2, wherein the tobacco starting material is heated at the extraction temperature for at least 120 minutes.

4. 4. The method of claim 1, wherein the extraction temperature is selected so that the tobacco flavorant composition has a weight ratio of (β-ionone + β-damascenone) to (phenol) of at least about 0.

25.

5. 5. The method of any one of claims 1 to 4, wherein the extraction temperature is selected such that the weight ratio of (β-ionone + β-damascenone) to (4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone + (R,S)-N-nitrosoanatabine + (R,S)-N-nitrosoanabasine + N-nitrosonornicotine + ((2-furanmethanol) / 600)) in the tobacco flavorant composition is at least about 1.

5.

6. The extraction temperature is such that the weight ratio of (furaneol + (2,3-diethyl-5-methylpyrazine) * 100) to (nicotine) in the tobacco flavoring composition is at least about 5 × 10 -4 The method according to any one of claims 1 to 5, wherein the .alpha.-to-.alpha.

7. The method of any one of claims 1 to 6, wherein the substrate comprises one or more of a gum, a starch, a hydrolyzed starch, a chemically modified starch, a carboxymethyl cellulose, a monosaccharide, a disaccharide.

8. 8. The method of claim 1, wherein the step of collecting the volatile compounds released from the tobacco starting material during the heating step comprises condensing the volatile compounds by cooling.

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