Patent Application
20250212939
The invention relates to aerosol-generating compositions, methods of manufacturing the suspensions and uses thereof.
Smoking articles such as cigarettes, cigars and the like burn tobacco during use to create tobacco smoke. Alternatives to these types of articles are non-combustible aerosol delivery systems that release compounds without burning to form an inhalable medium. Some such systems include a liquid which is vaporised by heating to produce an inhalable vapour or aerosol.
Liquid aerosol-generating materials for use in such products may include a variety of different active substances and/or flavours. Factors such as the concentration of the active and/or flavour components in the aerosol generating materials and the stability of the aerosol-generating materials will influence the properties of the aerosol generated.
According to a first aspect of the present invention, there is provided an aerosol-generating composition comprising a solid aerosol-generating material comprising a dried extract from a flavour- and/or active-containing plant material suspended or dissolved in a liquid aerosol-generating material.
In some embodiments, the liquid aerosol-generating material comprises one or more aerosol-former material.
In some embodiments, the one or more aerosol-former material is selected from the group consisting of: glycerol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-butylene glycol, erythritol, meso-Erythritol, ethyl vanillate, ethyl laurate, a diethyl suberate, triethyl citrate, triacetin, a diacetin mixture, benzyl benzoate, benzyl phenyl acetate, tributyrin, lauryl acetate, lauric acid, myristic acid, and propylene carbonate.
In some embodiments, the aerosol-generating composition comprises from about 5 to about 35 mg solid aerosol-generating material per ml of the aerosol-generating composition.
In some embodiments, the aerosol-generating composition comprises from about 15 to about 25 mg solid aerosol-generating material per ml of the aerosol-generating composition.
In some embodiments, the solid aerosol-generating material is formed by drying a precursor composition comprising an extract from a flavour- and/or active-containing plant material.
In some embodiments, the precursor material is dried to a moisture content of from about 0 to about 5% (calculated on a wet weight basis).
In some embodiments, the precursor material comprises from about 10 to 100% by weight of the extract from a flavour- or active-containing plant material.
In some embodiments, the precursor material comprises from about 1 to about 36 wt % aerosol-former material.
In some embodiments, the precursor material comprises from 0 to about 40% by weight of an excipient.
In some embodiments, the excipient is one or more selected from the group consisting of include mannitol, sucrose, trehalose, lactose, sorbitol, raffinose, maltose, Dextran 10, Dextran 70, Dextran 90, maltodextrin, gelatin, agar, cyclodextrin, PEG 2000-6000, (PVP 10k).
In some embodiments, the precursor material comprises a liquid suspension comprising particles with an average particle size of no greater than about 1 mm, when measured by sieving.
In some embodiments, the plant material is selected from the group consisting of tobacco, eucalyptus, star anise, cocoa and hemp.
In some embodiments, the extract from a flavour- or active-containing plant material is an aqueous extract.
In some embodiments, the extract from a flavour- or active-containing plant material is an aqueous tobacco extract.
In some embodiments, the solid aerosol-generating material comprises from about 40 to about 99% by weight tobacco solids.
In some embodiments, the solid aerosol-generating material is in the form of particles with a maximum particle size of about 1 mm, when measured by sieving.
In some embodiments, the aerosol-generating composition is for use in an aerosol provision system.
According to a second aspect of the present invention, there is provided an article comprising a solid aerosol-generating material comprising a dried extract from a flavour- and/or active-containing plant material suspended or dissolved in a liquid aerosol-generating material.
In some embodiments, the article comprises the aerosol-generating composition according to the first aspect.
According to a third aspect of the present invention, there is provided a non-combustible aerosol-provision system comprising an aerosol-generating composition according to the first aspect.
In some embodiments, the system is vaping device or electronic nicotine delivery system.
In some embodiments, the system is a Hybrid delivery system comprising a further aerosol-generating material.
According to a fourth aspect of the present invention, there is provided a method of providing an aerosol-generating composition comprising:
In some embodiments, the precursor material is dried by spray-drying or freeze-drying.
In some embodiments, the method comprises adjusting the particle size of the solid aerosol-generating material to a maximum size of about 1 mm, when measured by sieving.
In some embodiments, the method comprises adjusting the particle size of any solid material in the precursor material to a maximum size of about 1 mm, when measured by sieving.
Embodiments of the invention will now be described, by way of example only, with reference to accompanying drawings, in which:
Conventional liquid aerosol-generating materials which are used to generate a vapour or aerosol in non-combustible aerosol delivery systems may contain flavour and/or actives and an aerosol-former material. For example, such liquids may comprise glycerol and a flavour. In some instances, they further comprise nicotine.
Such compositions are generally not effective at replicating the tobacco flavours.
Tobacco material or a tobacco extract may be used in combustible and non-combustible aerosol-generating devices, including hybrid devices and tobacco heating products, to provide the user with an aerosol with an authentic tobacco taste and texture. One issue encountered with such materials is that the content of the flavour, other volatile compound(s) and nicotine decreases with storage of the aerosol-generating material, dropping off particularly towards the end of the life of the material. This is because the more volatile components, including nicotine and many flavours and aromas, are readily released from the material. Additionally, as the moisture content of the aerosol-generating material increases through moisture absorption, the release of substances such as nicotine and flavours is negatively impacted. Aerosol-generating materials that are produced using conventional methods and procedures commonly need to be used within one to three days of production. There is therefore a need to improve the shelf life of the aerosol generating material.
A further issue associated with conventional aerosol-generating materials comprising tobacco material or a tobacco extract is that the concentration of the desired components such as nicotine and flavours is relatively low. This limits the concentration of these desired components in the aerosol generated. Additionally, this means that a relatively large amount of the aerosol-generating material is needed and, accordingly, high amounts of energy are required to heat the aerosol-generating material in order to release the desired components.
The present invention relates to aerosol-generating compositions comprising a solid aerosol-generating material suspended or dissolved in a liquid aerosol-generating material. The solid aerosol-generating material comprises a dried extract from a flavour- and/or active-containing plant material.
In some embodiments, the extract from a flavour- and/or active-containing plant material is a liquid solution or suspension and it may be dried or dehydrated using a process such as spray-drying or freeze-drying. The dried or dehydrated solid aerosol generating material may be formed from a precursor material comprising the extract from a flavour- and/or active-containing plant material.
The present invention addresses some of the most significant short-comings of conventional vapour systems, namely the provision of an aerosol that provides an authentic tobacco taste. Attempts have been made in the past to utilise liquid tobacco extracts in the e-liquids for vapour systems. However, these extracts tend to be very dilute when added to the other liquid components and so fail to provide the tobacco flavours in adequate amounts. There can also be issues with the stability of the liquid formulation as a result of the relatively high water content that can cause instability and shorten the shelf-life of the product. In contrast, the present invention provides the tobacco or other plant extract in an extremely concentrated form, which can provide a strong and authentic tobacco taste to the vaping experience. The taste experience is more authentic as the aerosol-generating compositions includes the wide range and complex blend of flavours from the plant, as well as providing these in concentrated form to ensure that these flavours may be perceived in the aerosol generated by the vapour system.
The aerosol-generating compositions comprising the dried extract from a flavour- and/or active-containing plant material comprise a high concentration of the flavour and/or active. As such, small amounts of the dried extract are sufficient to generate aerosol with desired active and flavour content. Further, the dried extract affords the aerosol generated from the aerosol-generating compositions with desirable sensory properties.
In some embodiments, the dried aerosol-generating material has a moisture content of from 0 to about 10%, or from 0 to about 5% (calculated on a wet weight basis), as measured by gas chromatography-thermal conductivity detector (GC-TCD) or Karl Fischer titration. In some embodiments, the moisture content of the dried aerosol-generating material is less than about 3 wt %, for example from about 0 to about 3 wt %, or from about 0.5 to about 2.5 wt %.
Karl Fischer titration is a classic method of chemical analysis for reliably determining the amount of water in a sample, and even just trace amounts. The method can be readily carried out using an automated Karl Fischer titrator. Similarly, the use of GC-TCD is also a well-established method for reliably determining the water content in a sample.
Unless stated otherwise, references to moisture content herein are references to the moisture content as measured by Karl Fischer.
The aerosol-generating compositions may be used in non-combustible aerosol provision systems.
An aerosol-generating material is a material that is capable of generating aerosol, for example when heated, irradiated or energized in any other way.
The solid aerosol-generating material included in the aerosol-generating compositions of the present invention comprises a dried extract from a flavour- and/or active-containing plant material.
In some embodiments, the solid aerosol-generating material is formed by drying a precursor material comprising an extract from a flavour- and/or active-containing plant material. The drying process is selected to retain the desired components of the precursor material and, therefore, the solid aerosol-generating material may comprise one or more active substances and/or flavours.
In some embodiments, the extract from a flavour- or active-substance containing plant material is an extract derived by contacting the plant material with a suitable solvent, such as an aqueous solvent or an alcohol such as ethanol. The liquid portion comprising the solvent and any dissolved plant components may then be separated or partially separated from the remaining solid plant material to provide the extract to be included in the precursor composition and dried.
The precursor material and/or the solid aerosol-generating material may also optionally include one or more other functional materials.
The invention enjoys the advantage of a solid aerosol-generating material that is formulated to have an increased shelf life and so it may be easily transported and stored. Without wishing to be bound by any particular theory, it is hypothesised that the low water content of the solid aerosol-generating material reduces evaporation over time of other solvents, and reduces degradation of nicotine and/or other volatile compounds. A low water content also inhibits microbial growth.
The solid aerosol-generating materials and the aerosol-generating compositions, including, for example, suspensions comprising the dried extract from a flavour- and/or active-containing plant material described herein are stable at a range of temperatures and humidities and have an increased shelf-life, and are therefore easy to store and transport. In some embodiments, the compositions may be stored at temperatures in the range of 0-35° C. In some embodiments, the compositions may be stored at a relative humidity of up to about 30%, or up to 50% or even up to 90% prior to use.
The solid aerosol-generating materials also have the advantage of having a high concentration of the desired components. This means that relatively small amounts of the solid aerosol-generating material are required and less energy is required to heat and release the desired components. Significantly, the aerosols generated from these materials also provide an authentic tobacco taste of reasonable strength.
In some embodiments, the extract from a flavour- or active-substance containing plant material is an extract derived from tobacco material.
The tobacco extract or material may be from or may be any type of tobacco and any part of the tobacco plant, including tobacco lamina, stem, stalk, ribs, scraps and shorts or mixtures of two or more thereof. Suitable tobacco extracts or materials include the following types: Virginia or flue-cured tobacco, Burley tobacco, Oriental tobacco, or blends of tobacco materials, optionally including those listed here. The tobacco may be expanded, such as dry-ice expanded tobacco (DIET), or processed by any other means. In some embodiments, the tobacco material may be reconstituted tobacco material. The tobacco may be pre-processed or unprocessed, and may be, for instance, solid stems (SS); shredded dried stems (SDS); steam treated stems (STS); or any combination thereof. The tobacco material may be fermented, cured, uncured, toasted, or otherwise pre-treated. The tobacco material may be provided in the form of cut rag tobacco. The cut rag tobacco can have a cut width of at least 15 cuts per inch (about 5.9 cuts per cm, equivalent to a cut width of about 1.7 mm) for example. The cut rag tobacco can be formed from a mixture of forms of tobacco material, for instance a mixture of one or more of paper reconstituted tobacco, leaf tobacco, extruded tobacco and bandcast tobacco.
The precursor material which is dried to form the solid aerosol-generating material may comprise at least about 10 wt %, at least about 15 wt %, at least about 20 wt %, at least about 25 wt %, at least about 30 wt %, at least about 35 wt %, or at least about 40 wt % tobacco solids (calculated on a wet weight basis). Additionally or alternatively, the precursor material may comprise up to about 60 wt %, up to about 55 wt %, up to about 50 wt %, up to about 45 wt %, or up to about 40 wt % tobacco solids (calculated on a wet weight basis). In some embodiments, the precursor material comprises from about 20 wt % to about 40 wt % tobacco solids (calculated on a wet weight basis).
In some embodiments, the precursor material comprises at least about 10 wt %, about 20 wt %, at least about 30 wt %, at least about 40 wt %, at least about 50 wt %, at least about 60 wt %, at least about 70 wt %, at least about 80 wt %, or at least about 90 wt % extract from a tobacco or other flavour- or active-substance containing plant material (calculated on a wet weight basis). Alternatively or additionally, precursor material may comprise up to about 99 wt %, up to about 90 wt %, up to about 80 wt %, up to about 70 wt % or up to about 60 wt % extract from tobacco or other flavour- or active-substance containing plant material (calculated on a wet weight basis). In some embodiments, the precursor material comprises around 50 wt % tobacco extract (calculated on a wet weight basis).
In some embodiments, the dried aerosol-generating material may comprise at least about 45 wt %, at least about 50 wt %, at least about 60 wt %, at least about 70 wt %, at least about 80 wt %, at least about 90 wt %, or at least about 95 wt % tobacco material or tobacco extract, or flavour- or active-substance containing plant material extract (calculated on a dry weight basis). In some embodiments, the dried aerosol-generating material may comprise about 60 to about 80 wt % tobacco extract (calculated on a dry weight basis).
In some embodiments, the dried aerosol-generating material may comprise from about 2 wt % to about 10 wt % of nicotine, or from about 3 to about 6 wt % of nicotine (calculated on a dry weight basis).
In some embodiments, the precursor material comprises around 50 v/v % tobacco extract. Where the precursor material comprises around 50 v/v % tobacco extract and the tobacco extract has a tobacco solid content of between about 55 and about 60 v/v %, the overall tobacco solid content of the precursor material is from about 27.5 to about 30 v/v %.
In some embodiments, the tobacco extract has a solids content of between about 40 and about 65 wt %, between about 45 and about 65 wt %, or between about 40 and about 60 wt % (calculated on a wet weight basis). In some embodiments, the water content of the tobacco extract is between about 35 wt % and about 65 wt %, or between about 35 and about 55 wt % (calculated on a wet weight basis). In some embodiments, the nicotine content of the tobacco extract is between about 1 wt % and about 5 wt % (calculated on a wet weight basis).
In some embodiments, the dried aerosol-generating material may comprise at least about 45 wt %, at least about 50 wt %, at least about 60 wt %, at least about 70 wt %, at least about 80 wt %, at least about 90 wt %, or at least about 95 wt % tobacco solids (calculated on a dry weight basis). Additionally or alternatively, the solid aerosol-generating material may comprise up to about 99 wt %, up to about 98 wt %, up to about 95 wt %, up to about 90 wt % or up to about 80 wt %. In some embodiments, the dried aerosol-generating material may comprise about 60 to about 80 wt % tobacco solids (calculated on a dry weight basis).
In some embodiments, the tobacco extract is an aqueous tobacco extract. In some embodiments, the tobacco extract may be concentrated and subsequently diluted before being added to the precursor material and dried. In other embodiments, the tobacco extract is not concentrated and may be used directly in the precursor material.
The precursor material may be in the form of a slurry, a suspension, a gel, a liquid or a solid, but in some embodiments which may be preferred, it is in the form of a suspension or liquid. In some embodiments, particles of solid material may be removed from the extract and/or from the precursor material by filtration and/or centrifugation.
In some embodiments, it may be desirable for any particles in the precursor composition to have an average particle size of no greater than about 3 mm, of no greater than 1 mm, of no greater than about 0.5 mm, or to have an average particle size of no greater than about 0.3 mm, when measured by sieving or by observing the size of the particles by SEM. If necessary, the extract or precursor material may be processed to ensure that they do not include particles with a size greater than desired when measured by sieving. In some embodiments, the extract or precursor material may be filtered or centrifuged in order to remove particles above a particular size. Alternatively or additionally, the extract or precursor material may be ground to reduce the size of any particles present.
The water content of the precursor material may be at least about 20 wt %, at least about 30 wt %, at least about 40 wt %, at least about 50 wt %, at least about 60 wt %, at least about 70 wt %, at least about 80 wt %, or at least about 90 wt % on a wet weight basis. Alternatively or additionally, the water content of the precursor material may be up to about 95 wt %, up to about 90 wt %, up to about 85 wt %, up to about 80 wt %, up to about 75 wt %, up to about 70 wt %, up to about 65 wt %, up to about 60 wt %, up to about 55 wt % or up to about 50 wt % on a wet weight basis. In some embodiments, the water content of the precursor material is between about 40 and about 50 wt % on a wet weight basis (50% and 60 v/v %). When the precursor material has a lower water content, the spray/freeze-drying process is quicker, as there is less water to remove.
In some embodiments, the solid aerosol-generating material and/or the precursor material comprises one or more active substance. This may be derived from the extract or it may be added. In some embodiments, the extract from a flavour- or active-substance containing plant material comprises an active substance.
The active substance may be a physiologically active material, which is a material intended to achieve or enhance a physiological response. The active substance may for example be selected from nutraceuticals, nootropics and psychoactives. The active substance may comprise, for example, nicotine, caffeine, taurine, theine, vitamins such as B6 or B12 or C, melatonin, cannabinoids, or constituents, derivatives, or combinations thereof. The active substance may comprise one or more constituents, derivatives or extracts of tobacco, cannabis or another botanical.
In some embodiments, the active substance comprises nicotine. In some embodiments, the active substance comprises caffeine, melatonin or vitamin B12.
In some embodiments, the precursor material may comprise an extract from other botanical source(s) along with or instead of the tobacco extract.
As noted herein, the extract may comprise or be derived from one or more botanicals or constituents, derivatives or extracts thereof. As used herein, the term “botanical” includes any material derived from plants including, but not limited to, extracts, leaves, bark, fibres, stems, roots, seeds, flowers, fruits, pollen, husk, shells or the like. The extract may comprise or be derived from botanicals in the form of liquid, gas, solid, powder, dust, crushed particles, granules, pellets, shreds, strips, sheets, or the like.
Example botanicals are tobacco, eucalyptus, star anise, hemp, cocoa, cannabis, fennel, lemongrass, peppermint, spearmint, rooibos, chamomile, flax, ginger, Ginkgo biloba, hazel, hibiscus, laurel, licorice (liquorice), matcha, mate, orange skin, papaya, rose, sage, tea such as green tea or black tea, thyme, clove, cinnamon, coffee, aniseed (anise), basil, bay leaves, cardamom, coriander, cumin, nutmeg, oregano, paprika, rosemary, saffron, lavender, lemon peel, mint, juniper, elderflower, vanilla, wintergreen, beefsteak plant, curcuma, turmeric, sandalwood, cilantro, bergamot, orange blossom, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, geranium, mulberry, ginseng, theanine, theacrine, maca, ashwagandha, damiana, guarana, chlorophyll, baobab or any combination thereof. The mint may be chosen from the following mint varieties: Mentha Arventis, Mentha c.v., Mentha niliaca, Mentha piperita, Mentha piperita citrata c.v., Mentha piperita c.v., Mentha spicata crispa, Mentha cardifolia, Mentha longifolia, Mentha suaveolens variegata, Mentha pulegium, Mentha spicata c.v. and Mentha suaveolens
In some embodiments, the extract comprises or is derived from one or more botanicals or constituents, derivatives or extracts thereof selected from eucalyptus, star anise, cocoa and hemp.
In some embodiments, the extract comprises or is derived from one or more botanicals or constituents, derivatives or extracts thereof selected from rooibos and fennel.
In some embodiments, the solid aerosol-generating material and/or the precursor material comprises one or more cannabinoid compounds selected from the group consisting of: cannabidiol (CBD), tetrahydrocannabinol (THC), tetrahydrocannabinolic acid (THCA), cannabidiolic acid (CBDA), cannabinol (CBN), cannabigerol (CBG), cannabichromene (CBC), cannabicyclol (CBL), cannabivarin (CBV), tetrahydrocannabivarin (THCV), cannabidivarin (CBDV), cannabichromevarin (CBCV), cannabigerovarin (CBGV), cannabigerol monomethyl ether (CBGM) and cannabielsoin (CBE), cannabicitran (CBT).
The solid aerosol-generating material and/or the precursor material may comprise one or more cannabinoid compounds selected from the group consisting of cannabidiol (CBD) and THC (tetrahydrocannabinol).
The solid aerosol-generating material and/or the precursor material may comprise cannabidiol (CBD).
The solid aerosol-generating material and/or the precursor material may comprise nicotine and cannabidiol (CBD).
The solid aerosol-generating material and/or the precursor material may comprise nicotine, cannabidiol (CBD), and THC (tetrahydrocannabinol).
The solid aerosol-generating material further comprises an aerosol-former material. In some embodiments, this aerosol-former material is included in the precursor material.
In some embodiments, the precursor material comprises at least about 1 wt %, at least about 5 wt %, at least about 10 wt %, or at least about 20 wt % aerosol-former material (calculated on a wet weight basis). Additionally or alternatively, the precursor material may comprise up to about 40 wt %, up to about 35, up to about 30 wt %, up to about 25 wt %, up to about 20 wt %, or up to about 10 wt % aerosol-former material (calculated on a wet weight basis).
In embodiments of the invention in which the aerosol-former material is glycerol, the precursor material may comprise at most 36 wt % of glycerol. The inventors have demonstrated that dry weight inclusion levels up to 36 wt % (calculated on a dry weight basis) of aerosol-former material are possible.
The amount of glycerol in the precursor material, and therefore the solid aerosol-generating material, is important because it is both an aerosol-forming material and also a plasticizer. If the concentration of glycerol it too high, it may be detrimental to a critical temperature of the product during the freeze-drying process and may result in collapse of the product if the critical temperature of the formulation is exceeded.
As glycerol and some other aerosol-former materials are considered to have anti-freeze properties, it is particularly surprising that it is possible to freeze-dry a precursor material comprising such materials. Nevertheless, the inventors have discovered that precursor materials comprising glycerol may be freeze dried to form a highly useful aerosol-generating material.
In some embodiments, the solid aerosol-generating material may comprise at least about 1 wt %, at least about 5 wt %, at least about 10 wt %, at least about 20 wt %, at least about 30 wt %, or at least about 40 wt % aerosol-former material (calculated on a dry weight basis).
In some embodiments, the solid aerosol-generating material may comprise from about 1 to about 34 wt %, or from about 17 to about 34 wt % aerosol-former material (calculated on a dry weight basis). In some embodiments in which the aerosol-former material is glycerol, the dried aerosol-generating material may comprise from about 13 to about 34 wt % glycerol (calculated on a dry weight basis).
In embodiments in which Burley tobacco is used, the aerosol-generating material may comprise from about 17 to about 36 wt % of glycerol. The amount of glycerol in the aerosol material is important because it is both an aerosol-forming material and a plasticizer. If the concentration of glycerol is too high, it may be detrimental to the critical temperature of the product during the freeze-drying process and may result in collapse of the product if a critical temperature of the formulation is exceeded. On the other hand, sufficient glycerol should be included to provide the consumer with an adequate and pleasing aerosol.
In some embodiments, the solid aerosol-generating material and/or the precursor material further comprises one or more excipients. In some embodiments, the excipient stabilises and preserves the precursor material and the inventors have found the inclusion of an excipient especially important for stability when the precursor material comprised glycerol as the aerosol-forming material. The excipient may also act as a bulking agent or a filler material. In some embodiments, the inclusion of an excipient may also improve the handleability of the dried aerosol-generating material, helping it to retain its granular form by helping to reduce moisture uptake and the resulting increase in tackiness of the material. The presence of an excipient may also have an effect on the speed of (freeze) drying.
Suitable excipients include mannitol, sucrose, trehalose, lactose, sorbitol, raffinose, maltose, dextrans such as Dextran 10, Dextran 70, Dextran 90, maltodextrin, gelatin, agar, cyclodextrins, and polyethylene glycols such as PEG 2000-6000, and polyvinylpyrrolidone (PVP 10).
In some embodiments, the solid aerosol-generating material and/or the precursor material comprises one or more excipients in an amount of from 0 to about 40 wt % on a wet weight basis. In some embodiments, the precursor material may comprise at least about 1 wt %, at least about 10 wt %, at least about 20 wt %, at least about 30 wt %, and/or up to about 40 wt %, up to about 30%, up to about 20 wt %, or up to about 10 wt % excipient on a wet weight basis.
In some embodiments, the solid aerosol-generating material may comprise at least about 0.1 wt %, at least about 10 wt %, at least about 20 wt %, or at least about 25 wt % excipient (calculated on a dry weight basis). In some embodiments, the solid aerosol-generating material may comprise up to about 25%, up to about 20 wt %, up to about 15 wt %, or up to about 10 wt % excipient (calculated on a dry weight basis).
In an exemplary embodiment, the solid aerosol-generating material comprises about 36 wt % glycerol, about 45 wt % tobacco extract, and about 19 wt % excipient on a dry weight basis.
In another exemplary embodiment, the solid aerosol-generating material comprises from about 17 to about 39 wt % glycerol, from about 41 to about 76 wt % tobacco extract, and from 0 to about 28 wt % excipient on a dry weight basis.
In embodiments in which the excipient is agar, the precursor material may comprise 0 wt %, about 5 wt %, or about 10 wt % agar. The inventors have found that agar makes the precursor material more viscous and that the freeze-drying process is easier when the precursor material comprises a lower concentration of the agar excipient.
In some embodiments, the precursor material comprises about 50 wt % tobacco extract, from 0 to about 36 wt % aerosol forming agent (for example, from 0 to about 15 v/v %) and from 0 to about 40 wt % (for example, about 37.5 v/v %) excipient. The tobacco extract may comprise about 55 wt % tobacco solids and the overall tobacco solids content of the precursor material is about 27.5 wt %.
In some embodiments, the precursor material comprises about 50 wt % tobacco extract, up to about 36 wt % (for example, about 15 v/v %) glycerol and from 0 to about 40 wt % (for example, about 37.5 v/v %) excipient. The tobacco extract may comprise about 55 wt % tobacco solids and the overall tobacco solids content of the precursor material is about 27.5 wt %.
Some sample formulations of dried aerosol-generating materials formed from aqueous tobacco extracts are summarised in Table 1 below, with the amounts provided on a dry weight basis. These are theoretical values (before drying and inherent losses). Typically from about 80 to 89% of the glycerol is retained following the drying. Glycerol may be used as an aerosol-former material, but can be replaced or partially replaced with one or more other aerosol-former material such as those disclosed herein. The excipient used may be a dextran such as Dextran 70. Again, this may be replaced or partially replaced with alternative excipients, such as those disclosed herein.
The percentage content of nicotine in the formulation will depend on the type of tobacco used, and the presence of other components, i.e. the aerosol-former and the excipient.
In some embodiments, the solid aerosol-generating material and/or the precursor material comprises one or more binders. In some embodiments the one or more binder is selected from the group consisting of: thermoreversible gelling agents, such as gelatin; starches; polysaccharides; pectins; celluloses; cellulose derivatives, such as carboxymethylcellulose; and alginates.
In some embodiments, the solid aerosol-generating material and/or the precursor material comprises one or more flavour-modifier, flavour or flavourant. This may be derived from the extract or it may be added. As used herein, the terms “flavour” and “flavourant” refer to materials which, where local regulations permit, may be used to create a desired taste, aroma or other somatosensorial sensation in a product for adult consumers. They may include naturally occurring flavour materials, botanicals, extracts of botanicals, synthetically obtained materials, or combinations thereof (e.g., tobacco, cannabis, licorice (liquorice), hydrangea, eugenol, Japanese white bark magnolia leaf, chamomile, fenugreek, clove, maple, matcha, menthol, Japanese mint, aniseed (anise), cinnamon, turmeric, Indian spices, Asian spices, herb, wintergreen, cherry, berry, red berry, cranberry, peach, apple, orange, mango, clementine, lemon, lime, tropical fruit, papaya, rhubarb, grape, durian, dragon fruit, cucumber, blueberry, mulberry, citrus fruits, Drambuie, bourbon, scotch, whiskey, gin, tequila, rum, spearmint, peppermint, lavender, aloe vera, cardamom, celery, cascarilla, nutmeg, sandalwood, bergamot, geranium, khat, naswar, betel, shisha, pine, honey essence, rose oil, vanilla, lemon oil, orange oil, orange blossom, cherry blossom, cassia, caraway, cognac, jasmine, ylang-ylang, sage, fennel, wasabi, piment, ginger, coriander, coffee, hemp, a mint oil from any species of the genus Mentha, eucalyptus, star anise, cocoa, lemongrass, rooibos, flax, Ginkgo biloba, hazel, hibiscus, laurel, mate, orange skin, rose, tea such as green tea or black tea, thyme, juniper, elderflower, basil, bay leaves, cumin, oregano, paprika, rosemary, saffron, lemon peel, mint, beefsteak plant, curcuma, cilantro, myrtle, cassis, valerian, pimento, mace, damien, marjoram, olive, lemon balm, lemon basil, chive, carvi, verbena, tarragon, limonene, thymol, camphene), flavour enhancers, bitterness receptor site blockers, sensorial receptor site activators or stimulators, sugars and/or sugar substitutes (e.g., sucralose, acesulfame potassium, aspartame, saccharine, cyclamates, lactose, sucrose, glucose, fructose, sorbitol, or mannitol), and other additives such as charcoal, chlorophyll, minerals, botanicals, or breath freshening agents. They may be imitation, synthetic or natural ingredients or blends thereof. They may be in any suitable form, for example, liquid such as an oil, solid such as a powder, or gas.
In some embodiments, the flavour comprises menthol, spearmint and/or peppermint. In some embodiments, the flavour comprises flavour components of cucumber, blueberry, citrus fruits and/or redberry. In some embodiments, the flavour comprises eugenol. In some embodiments, the flavour comprises flavour components extracted from tobacco. In some embodiments, the flavour comprises flavour components extracted from cannabis.
In some embodiments, the flavour may comprise a sensate, which is intended to achieve a somatosensorial sensation which are usually chemically induced and perceived by the stimulation of the fifth cranial nerve (trigeminal nerve), in addition to or in place of aroma or taste nerves, and these may include agents providing heating, cooling, tingling, numbing effect. A suitable heat effect agent may be, but is not limited to, vanillyl ethyl ether and a suitable cooling agent may be, but not limited to eucolyptol, WS-3.
In some embodiments, the solid aerosol-generating material and/or the precursor material comprises one or more other functional materials, which may comprise one or more of pH regulators, colouring agents, preservatives, fillers, stabilizers, and/or antioxidants.
In some embodiments, the solid aerosol-generating material and/or the precursor material contains a filler component. The filler component is generally a non-tobacco component, that is, a component that does not include ingredients originating from tobacco. In some embodiments, the precursor material comprises less than 60 wt % of a filler, such as from 1 wt % to 60 wt %, or 5 wt % to 50 wt %, or 5 wt % to 30 wt %, or 10 wt % to 20 wt % on a wet weight basis.
The filler, if present, may comprise one or more inorganic filler materials such as calcium carbonate, perlite, vermiculite, diatomaceous earth, colloidal silica, magnesium oxide, magnesium sulphate, magnesium carbonate, and suitable inorganic sorbents, such as molecular sieves. The filler may comprise one or more organic filler materials such as wood pulp, hemp fibre, cellulose and cellulose derivatives.
In some embodiments, the solid aerosol-generating material is in the form of a gel. A gelling agent may be added to the aerosol-generating material, the precursor material or may be optionally omitted. The gelling agent may comprise one or more compounds selected from cellulosic gelling agents, non-cellulosic gelling agents, guar gum, acacia gum and mixtures thereof.
In some embodiments, the cellulosic gelling agent is selected from the group consisting of: hydroxymethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, carboxymethylcellulose (CMC), hydroxypropyl methylcellulose (HPMC), methyl cellulose, ethyl cellulose, cellulose acetate (CA), cellulose acetate butyrate (CAB), cellulose acetate propionate (CAP) and combinations thereof.
In some embodiments, the gelling agent comprises (or is) one or more of hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methylcellulose (HPMC), carboxymethylcellulose, guar gum, or acacia gum.
In some embodiments, the gelling agent comprises (or is) one or more non-cellulosic gelling agents, including, but not limited to, agar, xanthan gum, gum Arabic, guar gum, locust bean gum, pectin, carrageenan, starch, alginate, and combinations thereof. In preferred embodiments, the non-cellulose based gelling agent is alginate or agar.
The solid aerosol-generating material and/or the precursor material may comprise an acid. The acid may be an organic acid. In some of these embodiments, the acid may be at least one of a monoprotic acid, a diprotic acid and a triprotic acid. In some such embodiments, the acid may contain at least one carboxyl functional group. In some such embodiments, the acid may be at least one of an alpha-hydroxy acid, carboxylic acid, dicarboxylic acid, tricarboxylic acid and keto acid. In some such embodiments, the acid may be an alpha-keto acid.
In some such embodiments, the acid may be at least one of succinic acid, lactic acid, benzoic acid, citric acid, tartaric acid, fumaric acid, levulinic acid, acetic acid, malic acid, formic acid, sorbic acid, benzoic acid, propanoic and pyruvic acid. In some embodiments, the acid is selected from one of lactic acid, benzoic acid and levulinic acid.
In other embodiments the acid may be an inorganic acid. In some of these embodiments the acid may be a mineral acid. In some such embodiments, the acid may be at least one of sulphuric acid, hydrochloric acid, boric acid and phosphoric acid.
The inclusion of an acid is may be beneficial in embodiments in which the solid aerosol-generating material and/or the precursor material comprises nicotine. In such embodiments, the presence of an acid may stabilise dissolved species in the slurry from which the solid aerosol-generating material is formed. The presence of the acid may reduce or substantially prevent evaporation of nicotine during drying of the slurry, thereby reducing loss of nicotine during manufacturing.
In certain embodiments, the aerosol-generating material comprises a gelling agent comprising a cellulosic gelling agent and/or a non-cellulosic gelling agent, an active substance and an acid.
The solid aerosol-generating material may be in the form of particles, such as in the form of a powder. In some embodiments, the solid aerosol-generating material is in the form of particles with a maximum particle size of about 1 mm, 900 μm, 800 μm, 700 μm, 600 μm, 500 μm, 400 μm, 300 μm, 200 μm, 100 μm, 90 μm, 80 μm, 70 μm, 60 μm, 50 μm, 40 μm, 30 μm, 20 μm, or a maximum particle size of 10 μm, when measured by sieving. In some embodiments, the solid aerosol-generating material is in the form of particles with a minimum particle size of about 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, or a maximum particle size of 100 μm, when measured by sieving.
In some embodiments, the solid aerosol-generating material formed by freeze- or spray-drying and is then processed with other suitable steps as required and known to the person skilled in the art to provide the dried material in the desired form, for example in the form of particles of the desired size(s).
In some embodiments, the freeze dried precursor material is ground into particles and may be sieved to exclude particles that are considered too small or too large to be used as aerosol-generating material. In some embodiments, the freeze dried material used as the aerosol-generating material according to the present invention has a particle size distribution D10 from about 5 to about 25 μm (meaning that 10% of the particles in the tested sample are smaller than the value), a particle size distribution D50 from about 30 to about 200 μm (meaning that 50% of the particles in the tested sample are smaller than the value), and a particle size distribution D90 from about 500 to about 2500 μm (meaning that 90% of the particles in the tested sample are smaller than the value). These values are determined using particle size and shape analyser Microtrac CamSizer® X2. Percentages referred to here are volume percentages.
In some embodiments, the freeze dried material used as the aerosol-generating material according to the present invention has a particle size distribution D10 from about 8 to about 15 μm, a particle size distribution D50 from about 50 to about 150 μm, and a particle size distribution D90 from about 900 to about 1700 μm.
In some embodiments, the D10 mean is from about 10 to about 15 μm, the D50 mean from about 40 to about 140 μm and the D90 mean from about 800 to about 1600 μm.
The drying methods used to dry the precursor material may be any suitable drying process, including freeze-drying or spray-drying processes. The drying process used must be compatible with the precursor material and the desired make-up of the solid aerosol-generating material. As it may be desirable for the solid aerosol-generating material to include active and/or flavour substances derived from the extract in the precursor material, it is important to select a drying method that will retain a sufficient amount of these components.
In small scale examples, the precursor material is freeze-dried using freeze-drying microscopy, for example using a Lyostat freeze-drying microscope.
In a spray-drying process, the precursor material is sprayed and rapidly dried using a hot gas. The use of spray drying provides several advantages to the present invention: the dry particle size can be controlled and may be consistent; tobacco or flavour extracts or materials are heat sensitive but can still be spray-dried at relatively high inlet temperatures; a short residence time in the spray-drying equipment is required; and minimal loss of flavour/volatiles. This makes the process adaptable to reduce loss of volatile compounds and maintain the desired flavour of the aerosol generating material.
Freeze-drying, also known as lyophilisation or cryodesiccation, is a process in which the precursor material is frozen, the temperature lowered and the water is removed via sublimation under reduced pressure conditions. Without wishing to be bound by any specific theory, it is believed that the low processing temperatures and rapid water loss via sublimation avoid changes in the aerosol-generating material's structure, appearance and characteristics. This process preserves the structure of the precursor material, and reduces the loss and decomposition of volatile flavour compounds.
The solid aerosol-generating material has a lower water content than the precursor material. The water content of the solid aerosol-generating material may be at most about 0.5 wt %, about 1 wt %, about 2%, about 5 wt %, about 10 wt %, or about 20 wt % (calculated on a wet weight basis). The water content of the dried aerosol-generating material may be reduced from the precursor material by at least about 50 wt %, about 60 wt %, about 70 wt %, about 80 wt %, about 90 wt %, about 95 wt %, about 98 wt %, or by about 100 wt %. In some embodiments the dried aerosol-generating material has a water content of less than about 5 wt %, less than about 4 wt %, less than about 3 wt %, less than about 2 wt % or less than about 1 wt % (calculated on a wet weight basis), as measured by gas chromatography-thermal conductivity detector (GC-TCD) or Karl Fischer measurement.
In an exemplary embodiment of the invention, the precursor material comprises Burley tobacco extract and a water content of 60 wt %. After the freeze-drying operation described herein, the dried aerosol generating material has a water content of 3 wt %.
A lower water content of the dried aerosol-generating material is associated with longer shelf-life and stability. However, very low water content may be associated be a brittle structure and a smaller particle size, as well as taking longer to process. The material is also very hygroscopic. If the water content of the dried aerosol-generating material is too high on the other hand, the desired increased stability may not be achieved. The dried aerosol-generating material may also not be as easy to handle with higher water content, with the material becoming sticky.
The inventors have found that when the precursor material comprises an excipient, the precursor material may be better suited to being dried via spray-drying (compared to a precursor material without an excipient). Without wishing to be bound by any particular theory, it is speculated that increasing the amount of the excipient in the precursor material raises the glass transition temperature to above 100° C. and this affects the physical properties of the material, making it more suitable for spray drying.
The liquid aerosol-generating material may comprise one or more aerosol-former materials capable of forming an aerosol. The aerosol-former may be, for instance, a polyol aerosol generator or a non-polyol aerosol generator. It may be a solid or liquid at room temperature, but preferably is a liquid at room temperature.
In some embodiments, the aerosol-former material may comprise one or more of glycerine, glycerol, propylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,3-butylene glycol, erythritol, meso-Erythritol, ethyl vanillate, ethyl laurate, a diethyl suberate, triethyl citrate, triacetin, a diacetin mixture, benzyl benzoate, benzyl phenyl acetate, tributyrin, lauryl acetate, lauric acid, myristic acid, and propylene carbonate.
In some embodiments, the aerosol-former material comprises one or more polyhydric alcohols, such as propylene glycol, triethylene glycol, 1,3-butanediol and glycerin; esters of polyhydric alcohols, such as glycerol mono-, di- or triacetate; and/or aliphatic esters of mono-, di- or polycarboxylic acids, such as dimethyl dodecanedioate and dimethyl tetradecanedioate. In some embodiments, the aerosol-former material comprises one or more compounds selected from erythritol, propylene glycol, glycerol, vegetable glycerine (VG), triacetin, sorbitol and xylitol.
In some embodiments, the aerosol-former material comprises, consists essentially of or consists of glycerol. Glycerol provides a visible aerosol when the aerosol-generation device is used. It is common that consumers like the aerosol generating device to provide a visible aerosol, as this enables the consumer to visualise the product and what they are consuming. This makes glycerol a desirable choice for aerosol former material. Propylene glycol has the benefit that it is a better flavour carrier than glycerol.
A combination of two or more aerosol forming agents may be used, in equal or differing proportions.
In some embodiments, the liquid aerosol-generating material comprises or consists of one or more selected from: glycerol, propylene glycol and vegetable glycerol.
In some embodiments, the liquid aerosol-generating material may comprise further components, such as flavours. For example, in some embodiments, the liquid aerosol-generating material comprises propylene glycol and a flavour. The flavour may be any one of the flavours mentioned herein.
In some embodiments, the liquid aerosol-generating material further comprises a solvent that enhances the dissolution of the dried aerosol-generating material. For example, the liquid aerosol-generating material may comprise a water component to dissolve the dried aerosol generating material. As the addition of water may have a negative effect on the stability and shelf-life of the composition, and it will also increase the amount of energy required to volatilise the liquid aerosol-generating material, it may be desirable to keep the water content as low as possible. In some embodiments, the liquid aerosol-generating material comprises up to about 5% v/v water, up to about 4%, up to about 3%, up to about 2.5%, up to about 2%, up to about 1.5%, or up to about 1% v/v water.
The aerosol-generating compositions are formed by combining the solid and liquid aerosol-generating materials.
In some embodiments, the solid aerosol-generating material is not soluble in the liquid aerosol-generating material and the composition is a suspension.
In other embodiments, the solid aerosol-generating material is at least partially soluble in the liquid aerosol-generating material and the composition is a suspension or a solution.
Where the aim is to produce a solution, dissolution of the solid aerosol-generating material may be enhanced or accelerated by providing the solid aerosol-generating material in the form of fine particles. For example, the particles may have an average particle size of no greater than about 100 μm, of no greater than about 50 μm, of no greater than about 25 μm, or to have an average particle size of no greater than about 10 μm, when measured by sieving.
In some embodiments, an aerosol-generating composition which is a suspension may be filtered or centrifuged in order to remove particles above a particular size.
In order to provide the aerosol-generating composition in the form of a solution, it may be possible to select a liquid aerosol-generating material with one or more components in which the solid aerosol-generating material is soluble. For example, as discussed above, the liquid aerosol-generating material may comprise a solvent.
Alternatively or additionally, in order to provide the aerosol-generating composition in the form of a solution, it may be possible to formulate the solid aerosol-generating material to exclude any components that are not soluble in the liquid aerosol-generating material. In some embodiments, the solid aerosol-generating material does not include an excipient that is insoluble in the liquid aerosol-generating material. In some embodiments, the solid aerosol-generating material includes an excipient or other components that are readily soluble in the liquid aerosol-generating material of the aerosol-generating composition.
In order to provide the aerosol-generating composition in the form of a solution, it may be possible to formulate the solid aerosol-generating material to exclude any components that are not soluble in the liquid aerosol-generating material.
The delivery systems described herein can be non-combustible aerosol provision systems.
As used herein, the term “delivery system” is intended to encompass systems that deliver at least one substance to a user, and includes:
According to the present disclosure, a “non-combustible” aerosol provision system is one where a constituent aerosol-generating material of the aerosol provision system (or component thereof) is not combusted or burned in order to facilitate delivery of at least one substance to a user.
In some embodiments, the delivery system is a non-combustible aerosol provision system, such as a powered non-combustible aerosol provision system.
In some embodiments, the non-combustible aerosol provision system is an electronic cigarette, also known as a vaping device or electronic nicotine delivery system (END), although it is noted that the presence of nicotine in the aerosol-generating material is not a requirement.
In some embodiments, the non-combustible aerosol provision system is an aerosol-generating material heating system, also known as a heat-not-burn system. An example of such a system is a tobacco heating system.
In some embodiments, the non-combustible aerosol provision system is a hybrid system to generate aerosol using a combination of aerosol-generating materials, one or a plurality of which may be heated. Each of the aerosol-generating materials may be, for example, in the form of a solid, liquid or gel and may or may not contain nicotine. In some embodiments, the hybrid system comprises a liquid or gel aerosol-generating material and a solid aerosol-generating material. The solid aerosol-generating material may comprise, for example, tobacco or a non-tobacco product.
The present invention also relates to a consumable or article, comprising a solid aerosol-generating material comprising a dried extract from a flavour- and/or active-containing plant material suspended or dissolved in a liquid aerosol-generating material.
Typically, the non-combustible aerosol provision system may comprise a non-combustible aerosol provision device and a consumable for use with the non-combustible aerosol provision device.
In some embodiments, the disclosure relates to consumables comprising aerosol-generating material and configured to be used with non-combustible aerosol provision devices. These consumables are sometimes referred to as articles throughout the disclosure.
In some embodiments, the non-combustible aerosol provision system, such as a non-combustible aerosol provision device thereof, may comprise a power source and a controller. The power source may, for example, be an electric power source or an exothermic power source. In some embodiments, the exothermic power source comprises a carbon substrate which may be energised so as to distribute power in the form of heat to an aerosol-generating material or to a heat transfer material in proximity to the exothermic power source.
In some embodiments, the non-combustible aerosol provision system may comprise an area for receiving the consumable, an aerosol generator, an aerosol generation area, a housing, a mouthpiece, a filter and/or an aerosol-modifying agent.
In some embodiments, the consumable for use with the non-combustible aerosol provision device may comprise aerosol-generating material, an aerosol-generating material storage area, an aerosol-generating material transfer component, an aerosol generator, an aerosol generation area, a housing, a wrapper, a filter, a mouthpiece, and/or an aerosol-modifying agent.
The apparatus 11 of
The heating chamber 14 is contained within the housing 12. There may be a support and/or insulating means (not shown) positioned between the heating chamber 14 and the housing 12, for example to assist in heat-insulating the housing 12 from the heating chamber 14, so that the housing 12 does not become hot or at least too hot to touch during use.
The housing 12 includes an inlet 15 through which air is drawn into the apparatus. The housing 12 also includes an outlet 17 at a mouthpiece 18 of the apparatus 11. Air is drawn into the apparatus 11 through the inlet 15, travels through the apparatus and, picking up the aerosol released by the aerosol-generating composition. The resulting aerosol generated by the apparatus 11 leaves the apparatus 11 through the outlet 19 and is inhaled by the user.
In other embodiments, the non-combustible aerosol provision system is a hybrid system to generate aerosol using a combination of aerosol-generating materials, one or a plurality of which may be heated and may be an aerosol-generating composition as disclosed herein comprising solid and liquid aerosol-generating materials as a solution or suspension. The further aerosol-generating material(s) may be, for example, in the form of a solid, liquid or gel and may or may not contain nicotine. In some embodiments, the solid aerosol-generating material may comprise, for example, tobacco or a non-tobacco product.
In some embodiments, the aerosol-generating composition which is a solution or a suspension is heated to generate a vapour and/or aerosol. The concentrated flavour- and/or active provided by the solid aerosol-generating material adds flavour and/or active to the vapour and/or aerosol, such as an authentic tobacco taste and nicotine delivery
The vapour and/or aerosol generated from the aerosol-generating composition which is a solution or a suspension may contact the further aerosol-generating material and may, as a consequence, heat the further aerosol-generating material to volatilise components thereof. In other embodiments, the further aerosol-generating material is heated by a separate heating means.
In other embodiments, vapour and/or aerosol generating by the two aerosol-generating materials in the Hybrid system are generated separately and combine in the device or on exit from the device.
The apparatus 21 further has an electronics/power chamber 27 which may, for example, contain electrical control circuitry and/or a power source (not shown). The electrical control circuitry may include a controller, such as a microprocessor arrangement, configured and arranged to control the heating of the container 23 and/or its contents, and of the liquid 26 via one or more heating elements (not shown). The electrical control circuitry may allow the apparatus 21 to be puff-actuated, so as to cause heating “on demand”. As an alternative, the apparatus 22 may have a manually operable switch for a user to initiate a puff.
The housing 22 also includes an inlet 28 through which air is drawn into the apparatus. The housing 22 also includes an outlet 29 at a mouthpiece 30 of the apparatus 21. Air is drawn into the apparatus 21 through the inlet 28, travels through the apparatus picking up the vapour created by heating the liquid 26 in the liquid reservoir 25, and flavour and/or active components released by the container 23, and the resulting aerosol generated by the apparatus 21 leaves the apparatus 21 through the outlet 29 and is inhaled by the user.
The Hybrid device 21 shown schematically in
In one embodiment, the liquid reservoir is positioned upstream of the solid aerosol-generating material to be volatilised. Alternatively, the liquid reservoir may be positioned downstream of the solid aerosol-generating material to be volatilised. In a yet further arrangement, the two sources of aerosol in the apparatus may be arranged side-by-side, etc.
The invention enjoys the advantage of longer shelf life than other tobacco extracts.
The nicotine content of the precursor and solid aerosol-generating material after the freeze drying process has been calculated, providing an indication of the amount of nicotine retained following the processing. Compared to the original tobacco extract, the nicotine recovery of the dried aerosol generating material is at least about 76 wt % on a dry weight basis. The nicotine recovery of the dried aerosol generating material compared to the original tobacco extract may be at least about 60%, at least about 70%, at least about 75%, at least about 80%, or at least about 90% on a dry weight basis.
The glycerol content of the precursor and dried aerosol-generating material after the freeze drying process has been calculated, providing an indication of the amount of glycerol retained following the processing. Compared to the precursor material, the glycerol recovery of the dried aerosol generating material is at least about 85%. The glycerol recovery of the dried aerosol generating material compared to the precursor material may be at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90% at least about 95% on a dry weight basis.
In a first test, the precursor material comprised essentially of aqueous tobacco extract, and glycerol. The aqueous tobacco extract was diluted further with glycerol up to about 24 wt % (calculated on a dry weight basis). The Burley aqueous tobacco extract had a tobacco solid content of about 40 wt %, and a water content of about 60 wt %. The precursor material was dried via freeze drying.
In a further test, the precursor material comprised essentially of aqueous tobacco extract, glycerol and Dextran 70. The glycerol content was about 0 to about 15 v/v %, or up to about 36 wt % calculated on a dry weight basis. The precursor material was dried via freeze drying.
The freeze-dried material of Example 1 or Example 2 is ground to provide a loose powder with an average size of from about 10 μm to about 50 μm. 50 mg of the powder is then added to 800 mg of a liquid component comprising 50% vegetable glycerol and 50% propylene glycol by volume. This aerosol-generating composition is used in a vapour device to provide at least 150 puffs.
The freeze-dried material of Example 1 or Example 2 is ground to provide a loose powder with an average size of from about 10 μm to about 50 μm. 20 mg of the powder is then added to 1 ml of a liquid component comprising 60% propylene glycol, 35% vegetable glycerol and 5% water by volume. This aerosol-generating composition forms a solution with no particulate matter and is used in a vapour device to provide at least 200 puffs.
The various embodiments described herein are presented only to assist in understanding and teaching the claimed features. These embodiments are provided as a representative sample of embodiments only, and are not exhaustive and/or exclusive. It is to be understood that advantages, embodiments, examples, functions, features, structures, and/or other aspects described herein are not to be considered limitations on the scope of the invention as defined by the claims or limitations on equivalents to the claims, and that other embodiments may be utilised and modifications may be made without departing from the scope of the claimed invention. Various embodiments of the invention may suitably comprise, consist of, or consist essentially of, appropriate combinations of the disclosed elements, components, features, parts, steps, means, etc., other than those specifically described herein. In addition, this disclosure may include other inventions not presently claimed, but which may be claimed in future.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2204811.0 | Apr 2022 | GB | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/GB2023/050853 | 3/31/2023 | WO |
