WO2022003029A1

WO2022003029A1 - Method for preparing a tobacco product and tobacco liquid solution

Info

Publication number: WO2022003029A1
Application number: PCT/EP2021/068013
Authority: WO
Inventors: Ingo SCHEWZOW; Irina LUDES; Daniel Lickefeld; Thomas JOHAENTGES; Michael Plattner
Original assignee: Jt International Sa
Priority date: 2020-06-30
Filing date: 2021-06-30
Publication date: 2022-01-06
Also published as: EP4171272A1; JP2023530570A

Abstract

The invention relates to a method for preparing a tobacco product (21), which comprises the steps of providing raw tobacco (2) having a content of reducing sugars of at least 4% by weight, mixing (7) and infusing (10) the raw tobacco (2) with a first solvent (9), removing tobacco material (2a) to obtain an infused tobacco liquid (14), heating the infused tobacco liquid (14) thereby evaporating the first solvent (9a) and caramelizing (18) the reducing sugars thereby forming a preliminary caramelized tobacco product (20), drying (3) the removed tobacco material (2a) creating dried tobacco material (5) and adding the dried tobacco material (5) to the preliminary caramelized tobacco product (20) thereby creating a tobacco product (21). The invention also relates to a tobacco product (21). An aerosolisable product for an aerosol generation device containing the tobacco product (21), a smoking article containing the tobacco product (21) and a snus or a chewing article containing the tobacco product (21).

Description

Method for preparing a tobacco product and tobacco liquid solution

Description

The present invention relates to a method for preparing a tobacco product, a tobacco product, an aerosolisable product for an aerosol generation device containing a tobacco product, a smoking article containing the tobacco product and a snus or chewing article containing the tobacco product.

In nicotine containing consumable products like aerosolisable products for aerosol generating devices (e.g. e-cigarettes), snus, chewing articles or conventional smoking articles, often arti ficial flavorings are used. Such artificial flavorings often comprise the drawback of delivering an un-natural and therefore unsatisfying taste experience.

It is therefore the objective of the invention to provide a multi-purpose tobacco product usable in multiple nicotine containing consumable products, which eliminates the drawbacks and de livers a natural and pleasantly sweet tobacco taste. This objective is achieved by a method for preparing a tobacco product according to claim 1 . This method comprises the steps:

- providing raw tobacco having a content of reducing sugars of at least 4% by weight, wherein preferably the reducing sugars content of the raw tobacco is measured in a separate measuring step, - mixing and infusing the raw tobacco with a first solvent,

- removing tobacco material to obtain an infused tobacco liquid, - heating the infused tobacco liquid thereby evaporating the first solvent and caramel izing the reducing sugars thereby forming a preliminary caramelized tobacco product,

- drying the removed tobacco material creating dried tobacco material,

- adding the dried tobacco material to the preliminary caramelized tobacco product thereby creating a tobacco product.

The preliminary tobacco product preferably has a syrup-like, jam-like and/or honey-like texture.

The raw tobacco is defined as raw as it comes from reduced parts of the cured tobacco (flue, air, sun, fired curing). It can be a tobacco blend including different tobacco varieties without casing and flavor.

The reducing sugar content of the raw tobacco of at least 4 % by weight ensures sufficient reducing sugars in the liquid tobacco product for the caramelization reaction. Preferably the reducing sugars content of the raw tobacco is measured in a separate additional measuring step. The caramelization reaction turns the reducing sugars from the raw tobacco into cara melized sugar. With the caramelized sugar, the desired sweetness of the tobacco product is achieved. During mixing and infusing the raw tobacco with the first solvent, soluble substances like nicotine, other alkaloids, flavoring substances, sugar and reducing sugars are released from the raw tobacco and are solved in the first solvent. The removal of the tobacco material removes only the remaining solid component together with the substances insoluble in the first solvent. The remaining liquid denotes the infused tobacco liquid.

When heating the infused tobacco liquid, the first solvent is evaporated at least in part. After evaporation of the first solvent, the preliminary tobacco product may still comprise a certain level of the first solvent. Preferably the content of the first solvent in the preliminary tobacco product after evaporating the first solvent is between 0 - 20 % by weight. During the heating step the infused tobacco liquid is thickened and concentrated. This gives the preliminary to bacco product the honey-like or liquid viscous texture. Also the taste is intensified. This is achieved by caramelizing the reducing sugars, which are naturally present in the raw tobacco material. Due to the natural tobacco component and the caramelized sugar, the desired natural and sweet taste profile is achieved without any additives.

The removed tobacco material is dried. During the drying any solvent residues of the first sol vent in the removed tobacco material are evaporated. The drying is preferably carried out di rectly after the removal of the tobacco material. The drying is preferably carried out parallel to the heating and caramelization of the infused tobacco liquid. After the drying, the dried tobacco material is added, preferably mixed, to the preliminary tobacco product. By adding the dried tobacco material into the preliminary tobacco product, the resulting final tobacco product com prises an improved tobacco aroma. Also, the otherwise discarded removed tobacco material is subjected to further use thereby reducing the overall amount of waste.

The dried tobacco material can be milled before mixing to the preliminary tobacco product. The milling further reduces the particle size of the dried tobacco material. The particle size reduc tion after milling may be below 2 mm, preferably below 1.75 mm, even more preferred below 1 .2 mm It is also conceivable to further reduce the particle size towards tobacco dust, which preferably comprises a particle size between 90 - 100 pm.

The preliminary caramelized tobacco product may be mixed with a second solvent, such as before the dried tobacco material is mixed into the preliminary tobacco product to obtain a diluted preliminary caramelized tobacco product. This mixing can be carried out together with the mixing of the dried tobacco material into the preliminary caramelized tobacco product. It is also possible to first mix the preliminary caramelized tobacco product with the second sol vent and subsequently mix the diluted preliminary caramelized tobacco product with the dried tobacco material. In other words, preferably before, after or together with adding the dried to bacco material to the preliminary caramelized tobacco product, a second solvent is added to the mixture. Preferably, the solvent may be polyhydric alcohol such as PG, VG or water and combinations thereof. In other words, the second solvent preferably comprises water, or pro pylene glycol, or glycerol or combinations thereof. The ratio of preliminary tobacco product to solvent may be between 1 :1 to 1 :20, preferably 1 :1 to 1 :10 (in weight). The mixing of the dried tobacco material with the diluted preliminary tobacco product is then facilitated.

Preferably, the total sugar content of the tobacco product, which in this embodiment is a mix ture comprising the preliminary caramelized tobacco product, the dried tobacco material and the second solvent, is up to 5 wt.%, preferably between 0.1 and 2 wt. %, more preferably be tween 0.2 and 1 .5 wt. %. These values are wet based results.

Preferably, the reducing sugars content of the raw tobacco is detectable by the measuring step. It is conceivable that the measuring step comprises weighing of the raw tobacco to be provided for the method for preparing the tobacco product. Preferably after weighing the raw tobacco a carbonizing step is required. Also preferably the carbonized raw tobacco is misci ble with an extractive agent. During the mixing step the carbonized raw tobacco is dilutable in the extractive agent. The mixing step is preferably executable for at least 30 min. A ratio of raw tobacco, preferably carbonized raw tobacco, to extractive agent may be between 1 :8 to 1 :12, preferably 1 :10 (in weight). It is conceivable that the carbonized raw tobacco which is diluted in the extractive agent is heated up to 50°C in a separate heating step. Preferably the carbonized raw tobacco diluted in the extractive agent may be pre-filtered by a fine-pored material. The pre-filtered carbonized raw tobacco which is diluted in the extractive agent is preferably analyzed by chromatography, preferably high-performance liquid chromatography. Additionally, the carbonized raw tobacco which is diluted in the extractive agent is preferably treated with ultrasounds. It has been found that ultrasounds are advantageous for providing homogenous liquid of the diluted and carbonized raw tobacco. Preferably the homogenous liquid of the diluted and carbonized raw tobacco is particularly suitable for analysis by chro matography. For the analyzing step is preferably a calibration step necessary. Thus, it is con ceivable to calibrate the analytical equipment used for the analysis into a range between at least 4% and 9 % in particular for reducing sugar content. Preferably the analyzing step pro vides a total content of the reducing sugars of the raw tobacco. It is also conceivable that the analyzing step provides the content of individual sugars, preferably such as disaccharides, oligosaccharides, and polysaccharides, of the raw tobacco.

In case a second solvent is added, the tobacco product comprises a honey-like texture or a liquid texture depending on the dilution ratio with the second solvent.

The honey-like or liquid texture may also be desirable for easy processing in several different products. Also the tobacco product with this honey-like texture, but also the preliminary to bacco product denotes a concentrated product, which enables more effective storage and transport.

According to an aspect of the invention, a moisture content of the dried tobacco material may be between 0 - 15 % by weight, preferably between 0-13 % by weight. With this moisture content, the dilution of the tobacco product is not overly affected by the dried tobacco material and the dilution may be controlled by a taste neutral solvent and so desired taste profile is achieved.

The tobacco material removed is preferably entirely dried and added to the (diluted) preliminary tobacco product. The dried tobacco material can be mixed to the (diluted) preliminary tobacco product using a blended or mixer before filling into a vessel (e.g. packaging container, cap sules, cartridge, sachet, etc.) or be filled separately into a vessel without mixing. The dried tobacco material to the preliminary tobacco product may be mixed in a ratio between 1 :6 and 3:1 (in weight), preferably between 1 :5 and 1 :1. The given mixing ratios enable the selection of a suitable viscosity and taste profile of the tobacco product depending on the de sired use of the tobacco product.

During or after drying the removed tobacco material is roasted. By roasting the removed to bacco material, the aroma of the removed tobacco material is influenced. In particular, new or additional aroma compounds are created by roasting. During the roasting process, the re moved tobacco material is also dried. Preferably, the drying precedes the roasting although carried out in a single process. With the roasted aromas the overall taste profile of the tobacco product can be intensified for a stronger tobacco taste.

The roasting may take place at temperatures between 180°C to 260 °C. The given roasting temperatures ensure the proper formation of the roasted aromas. Preferably, the removed tobacco material undergoes a Maillard reaction and/or lignin pyrolysis at least in part during the roasting. In contrast to roasting, drying preferably takes place at temperatures below 180°C. As an example, the drying may take place at 116°C for 30 minutes.

The first solvent may be water and the infused tobacco liquid may be heated between 100 °C and 190°C. At the given temperatures the water can be evaporated as they are equal or larger to the boiling point of water (100 °C). Depending on the reducing sugar types contained in the infused tobacco liquid, different temperatures may be necessary to facilitate the caramelization reaction causing the browning of sugars and the development of polymers such as caramelans, caramelens, and caramelins.

The reducing sugars possibly contained in the tobacco material in variable concentration and their caramelization temperatures of are as follows:

- fructose: 110 °C (reducing sugar)

- galactose: 160 °C (reducing sugar)

- glucose: 160 °C (reducing sugar)

- sucrose: 160 °C (non-reducing sugar)

- maltose: 180 °C (reducing sugar).

Preferably, the infused tobacco liquid is heated to at least 110°C. Alternatively the infused tobacco liquid is heated to at least 160°C. The infused tobacco liquid may also be heated to at least 180 °C. The latter would allow all sugars contained in the liquid tobacco product to be caramelized, while the other two embodiments allow only for the caramelization of some sug ars. By selection of the heating temperature, the taste profile can be adjusted. During the heat ing step, a Maillard reaction may occur parallel to the caramelization reaction with the reducing sugars. This typically takes place at temperatures between 140 and 165 °C.

The raw tobacco may comprise a maximum content of reducing sugars of 30 % by weight. This reducing sugar content ensures the desired amount of sweetness in the ready-made to bacco product. Preferably, the raw tobacco comprises a reducing sugar content of 7 -10 weight %. This reducing sugar content delivers the optimal taste profile. Below 4 weight % of reducing sugar in the raw tobacco a significantly lower caramel sweet taste is perceivable in the final product, which is undesirable as the sweet taste of the final product is of high im portance to achieve the desired taste profile.

A preferred embodiment of the preliminary tobacco product contains at least 1.5 - 6 weight % nicotine, 6 - 15 % sugar and 14 - 20 % water.

Preferably, the raw tobacco is Virginia tobacco or an American Blend tobacco mixture. Ameri can Blend tobacco mixture typically contains flue cured Virginia tobacco, Oriental tobacco and Burley tobacco. Virginia tobacco contains high sugar levels. American Blend tobacco contains medium sugar levels. Both thus provide the desired sugar content in the raw tobacco. By using different tobacco types or blends, different taste profiles of the tobacco product can be achieved. By using a Virginia tobacco or blend thereof a tobacco product with a caramel-sweet taste profile can be obtained. By using an American Blend tobacco mixture a more spicy and licorice like taste profile can be obtained. However, any tobacco type or blend with a reducing sugar content of at least 4 weight % is applicable in this invention. Preferably, the tobacco could be Virginia tobacco, Burley tobacco, Oriental tobacco, Shade tobacco, White Burley to bacco, wild tobacco, Latakia tobacco, brightleaf tobacco, fire-cured tobacco, flue-cured to bacco, air-cured tobacco, sun-cured tobacco, Perique tobacco, Cavendish tobacco, Criollo to bacco and/or Dokha tobacco. Most preferably, the tobacco type or blend comprises a reducing sugar content of 20 % by weight or above, for example 24 % by weight.

The raw tobacco may comprise different parts of the tobacco plant material. The raw tobacco may comprise whole tobacco leaves, cut tobacco leaves, tobacco stems, tobacco pieces, to bacco scrap, tobacco fragments, tobacco powder and tobacco dust, wherein the latter may be side products of tobacco cut filler production. This increases the yield from the tobacco plant material.

The raw tobacco may have a maximum particle size of 20 mm. Preferably, the maximum par ticle size is 2 mm, most preferred 1 mm. This upper threshold for the particle size ensures optimal extraction of the soluble substances during the infusion, as with smaller particle size the overall surface area of the raw tobacco is increased, which promotes the interaction of the raw tobacco with the first solvent and increases the extraction efficiency. Preferably, the raw tobacco is grinded, to obtain the desired particle size.

The mixture of raw tobacco and first solvent preferably comprises at least 10 weight % of raw tobacco. By using at least 10 weight % of raw tobacco, a sufficient concentration of soluble substances is provided in the infused tobacco liquid. Preferably, the mixture comprises be tween 11 - 17 weight % raw tobacco. The resulting mixture preferably has a pulpy consistency. This is the optimum value for the infusion process.

The infusion of the raw tobacco with the first solvent preferably lasts at least 10 minutes, pref erably 20 minutes, especially preferably 1 hour, before the tobacco material is removed. This timespans ensure sufficient extraction of the soluble substances from the raw tobacco into the first solvent. Preferably, the raw tobacco is infused with the first solvent at warm temperatures. Preferably, the warm temperature is 65 °C. By infusing at warm temperatures the infusion time can be reduced while obtaining the same extraction efficiency as for longer infusion times at room temperatures.

The tobacco material may be removed by filtration. Filtration is a very easy to apply process step. It is easily adjustable to specific processes. The pore sizes of the filter is selectable. This makes it possible to adjust the filtration result according to the process demands.

The viscosity of the caramelized preliminary tobacco product may be between 10 Pa.s and 100 Pa.s at 60 °C. The viscosity was measured with a Rheometer MCR 101 (Anton Paar) with a shear rate of 50 I/s. These viscosity values provide the syrup-like, jam-like and/or honey-like texture.

As already mentioned, before, after or together with adding the dried tobacco material to the preliminary caramelized tobacco product, preferably a second solvent is added to the mixture. By adding the second solvent, the viscosity of the tobacco product may be adapted to suit different manufacturing processes. The mixing with the second solvent can take place inde pendently from the tobacco product production and tailored to any subsequent manufacturing processes. This ensures the multi-purpose character of the tobacco product. The thereby ob tained tobacco liquid solution is aerosolisable with exception of the dried tobacco material. The second solvent is preferably mixed with the preliminary tobacco product before the product is mixed with the dried tobacco material to facilitate the dispersion of tobacco particles in the liquid. In alternative to this embodiment, the tobacco liquid solution may be prepared by sim ultaneously mixing the second solvent and the dried tobacco material with the preliminary to bacco product. The resulting mixture equals the resulting mixture of the first alternative. The latter alternative is advantageous over the first alternative if a complete production batch of the preliminary tobacco product is used for preparing the tobacco liquid solution. In this case, the manufacturing process can be sped up due to simultaneous execution of two production steps. If not the whole production batch of the preliminary tobacco product is used for preparing the tobacco liquid solution, the first alternative is advantageous, as the tobacco product batch can be easily divided into smaller batches, which are then subjected to the respective further pro cessing.

Preferably, the viscosity of the tobacco liquid solution, i.e. the preliminary tobacco product mixed with the dried tobacco material and with the second solvent, is 110 to 175 mPa.s at 20°C, preferably 120 to 165 mPa.s at 20°C.

The tobacco liquid solution, i.e. the preliminary tobacco product mixed with the dried tobacco material and with the second solvent, may comprise up to 5 wt.% sugar, preferably between 0.1 and 2 wt. %, more preferably between 0.2 and 1 .5 wt. % (wet based results).

A preferred embodiment of the tobacco liquid solution, i.e. the preliminary tobacco product mixed with the dried tobacco material and with the second solvent, contains between 0.5 and 2 weight % nicotine, between 0.1 -2 % sugar and 5-15 % water (wet based results).

Typically, about 70 wt. (dry base) % of nicotine content comes from the preliminary tobacco product during extraction and about 5-10 wt.% may be lost during processing, with the remain ing portion coming from the dried pulp material when incorporated in the preliminary tobacco product. Similarly, about 70 wt. (dry base) % of sugar comes from the preliminary tobacco product during extraction and about 20 wt. % may be lost during processing. Preferably, the second solvent comprises water, or propylene glycol, or glycerol or combina tions thereof. These types of second solvents do not compromise on the natural character and taste of the tobacco product.

The caramelized preliminary tobacco product may be diluted with the second solvent in a ratio between 1 :1 and 1 :20, for preferably between 1 :2 to 1 :10, for example 1 :5, 1 :55 or 1 :6, and further mixed with the previously removed dried tobacco material, preferably after particle size reduction. By this dilution a tobacco liquid solution is obtained. The dilution ratios may be ad justed to obtain an optimum nebulizing effect, when the tobacco liquid solution is used in an aerosol generating device. When used in an aerosol generating device, the tobacco liquid so lution is aerosolized. This implies that also the contained tobacco product with all its compo nents is aerosolized with exception of the dried tobacco material. The second solvent may comprise a ratio of propylene glycol to glycerol between: 1 :0 and 1 :1. In one example, the second solvent contains 60 weight % propylene glycol and 40 weight % of the glycerol. In another example, the second solvent contains 100 wt. % propylene glycol. Preferably, this embodiment of the second solvent is mixed with the caramelized tobacco product, wherein the amount of preliminary tobacco product in the tobacco liquid solution is up to 20 weight %. In this way the solubility limit is not exceeded. Preferably the tobacco liquid solution comprises 5 - 15 weight % preliminary tobacco product.

With 5 weight % of preliminary tobacco product mixed with a solution of 40 weight % propylene glycol and 60 weight % glycerol a pleasant taste with high smoke volume can be achieved. The smoke taste texture is milder with notes of almond. No leakage occurs in the aerosol generating device. With 10 weight % of tobacco product mixed with a solution of 40 weight % propylene glycol and 60 weight % glycerol a stronger taste can be obtained. The taste is rem iniscent of dark roast espresso with sweetness. The smoke taste texture is creamy, with a full body and can be slightly throat scratching.

The total sugar content may be comprised between 15 and 75 weight % of the diluted prelim inary tobacco product as liquid solution (i.e. the preliminary tobacco product mixed with the second solvent prior to addition of the dried tobacco material). Only with this sugar content in the tobacco liquid solution the desired taste is achievable. Below 15 weight % of sugar in the solution a significantly lower caramel sweet taste is perceivable in the final product, which is undesirable as the sweet taste of the final product is of high importance to achieve the desired taste profile. Preferably, the sugar content in the solution is above 25 weight %. This ensures sufficient sweetness in the final product. The objective is also reached by a tobacco product containing at least caramelized tobacco sugar and non-soluble tobacco particles having particles size lower than 2 mm. The tobacco product comprises all the already mentioned advantages together with the superior sweet and natural tobacco taste. The tobacco product is additive free.

Preferably, the tobacco liquid solution further comprises one or more components selected from the group consisting of: alkaloids, essential oils and combinations thereof. Nicotine as an alkaloid is therefore also included. These substances are naturally derived from the raw to bacco during the infusion step. Alternatively, such natural substances may also be added to the liquid tobacco solution to further tailor the taste profile.

Preferably, the tobacco product also comprises a solvent. With the solvent the viscosity of the tobacco product can be adjusted. With the solvent, the tobacco product equals the previously mentioned tobacco liquid solution. The tobacco product with the solvent, i.e. the tobacco liquid solution, is aerosolisable with exception of the dried tobacco material. It delivers a full volume and immediate vaping effect, when aerosolized in an aerosol generating device. The aeroso lized tobacco liquid solution delivers as natural balanced tobacco taste with an enhanced roast note.

Preferably, the tobacco product with the solvent, i.e. the tobacco liquid solution, comprises a viscosity between 110 to 175 mPa.s at 20°C. This viscosity is preferred for aerosolisability.

The objective is also reached by an aerosolisable product for an aerosol generation device containing the tobacco product, i.e. the tobacco liquid solution, obtained by any of the previ ously described methods. The aerosol generating device can be a liquid nebulizer nebulizing liquid droplets at ambient temperature or an atomizer vaporizing aerosol at volatilization tem perature of the second solvent. The aerosolisable product makes the superior natural and sweet tobacco taste of the tobacco product available for the use in any aerosol generating devices. Especially for aerosolisable products there is a huge demand for natural tobacco fla vors and natural products in contrast to the broadly availably aerosolisable products containing artificial flavoring agents. Preferably, the aerosolisable product also comprises further natural flavoring substances. Preferably, the natural flavoring substance is eugenol and/or menthol. In this manner, the specific taste of eugenol or menthol containing cigarettes can be mimicked with the aerosolisable product. Preferably, the eugenol content is between 1 and 8 % weight, most preferably about 6 weight %. The aerosol generating device in this embodiment can also be a heat not burn device (T-vape) for an aerosolisable product which comprises reconstituted tobacco (RTB) with a certain amount of tobacco product or as main ingredient in a porous sachet. It can be used as additive with the RTB. Also, a tobacco mousse can be mixed with the tobacco product, preferably in proportions of 10:1 , most preferred of 5:1. For example 20 g of mousse and 5 g of tobacco product can be mixed to obtain the tobacco mousse. A foam or mousse of tobacco is described in international patent WO2018122375 for example. It can comprise a tobacco ingredient con taining agent and/or inhalable agent, an aerosol forming agent, a foam stabilizing agent and a foam forming agents. The weight of the tobacco ingredient can be 0.1 -33 wt.% of the weight of the foam, and the weight of the aerosol forming agent is 10-80 wt. %, preferably 40-70 wt. % of the weight of the foam.

The use of the tobacco product in heat not burn devices (T-Vape) is highly advantageous. It provides a natural tobacco taste with a full volume and immediate vaping effect. Also, the nicotine-to-TPM (total particulate matter) per puff is high compared to conventional cigarettes. With the tobacco mousse containing the tobacco product a taste and vape delivery enhance ment is realized.

The objective is also reached by a smoking article containing a tobacco product obtained by any of the previously described methods. The smoking article containing the tobacco product comprises a superior taste profile with intensified tobacco taste and a sweet aroma. By using the tobacco product smoking articles can be effectively aromatized without using artificial fla voring agents. The whole product, although aromatized, remains a completely natural products without any artificially made additives. The tobacco product may either be applied to the smok ing article with or without containing the (second) solvent.

The objective is also reached by a snus or chewing article containing the tobacco product obtained by any of the previously described methods. This again highlights the multi-purpose character of the tobacco product. With the tobacco product also snus or chewing article can be flavored in a natural and effective way, without the need for artificial flavoring agents provid ing a natural and sweet tobacco taste. Again, the tobacco product may either be applied to the snus or chewing article with or without containing the (second) solvent.

The tobacco product obtained by any of the previously described methods may also be used as natural taste enhancer for cigarettes or other tobacco materials, in T-vape sticks, T-vape rings, T-vape chips, in heat-not-burn products, as natural taste enhancer for non-tobacco ma terials, as insect repellent, with foam, in candy, in chewing gum, in sprays for smoking cessa tion or as lip stick. The tobacco product is also usable for aromatizing tobacco in primary or secondary processes.

The tobacco product as aforementioned may also be used in an aerosol generation device comprising caramelized sugar and having syrup-like, jam-like and/or honey-like texture. For example, the product can be wrapped in porous paper. Preferably, this arrangement can be used in a heat-not-burn device.

In the present application, the reducing sugars are any sugars capable of acting as a reducing agent because it has a free aldehyde group or a free ketone group. The reducing sugars are monosaccharides. The total sugars refer to reducing sugars, disaccharides, oligosaccharides, and polysaccharides.

Caramelization refer to the browning reaction of sugar obtained by heating or cooking, produc ing polymers such as: caramelans, caramelens and caramelins and producing volatile com pounds such as diacetyl, hydroxymethylfurfural, which are responsible for the caramel flavor.

Further advantages, objectives and features of the present invention will be described, by way of example only, in the following description with reference to the appended figures. In the figures, like components in different embodiments can exhibit the same reference symbols. The figures show:

Fig. 1 schematic view of the process flow of the method for preparing a tobacco prod- uct 21 ;

Fig. 2 schematic view of an alternative process flow of the method for preparing a pre liminary tobacco product 20 and a liquid tobacco solution 22;

Fig. 3 schematic view of an alternative process flow of the method for preparing a to bacco product 21 and a liquid tobacco solution 22.

Figure 1 shows schematic view of the process flow of the method for preparing a tobacco product 21. The raw tobacco 2 comprises a minimum content of reducing sugars of 4 weight % and preferably a maximum content of reducing sugars of 30 weight %. Preferably the re ducing sugars content of the raw tobacco is measured in an additional measuring step. Pref erably, the raw tobacco has a maximum particle size of 20 mm, preferably 2 mm, most pre ferred 1 mm.

In a first step, raw tobacco 2 is provided. In a subsequent mixing step 7, this raw tobacco 2 is mixed with a first solvent 9 to obtain a tobacco-solvent mixture 8. The first solvent 9 preferably is water. The tobacco-solvent mixture 8 preferably comprises at least 10 weight % of raw to bacco 2.

The obtained tobacco-solvent mixture 8 is then infused in an infusion step 10 for at least 10 minutes. Preferably, the tobacco-solvent mixture 8 is infused for 20 minutes, even more pre ferred 1 hour. The infusion step 10 may include heating of the tobacco-solvent mixture 8 to 65°C. The infusion step may also be carried out at ambient temperature or at temperature between ambient and 65°C.

After the infusion step 10, tobacco material 2a is removed from the tobacco-solvent mixture 8 in a removal step 12. The removed tobacco material 2a denotes mainly the insoluble solid components. The removal step may comprise filtering to remove the tobacco pulp from the infused liquid such as using a press or centrifugation. The removed tobacco material 2a is then subjected to a drying and optional roasting step 3. During the drying 3, residues of the first solvent 9 in the removed tobacco material 2a are preferably removed. From the drying and/or roasting 3 of the removed tobacco material 2a, a dried tobacco material 5 is obtained.

The soluble components of the raw tobacco 2 or at least most of them, are solved in the first solvent 9. With the removal step 12, the infused tobacco liquid 14 is obtained. The infused tobacco liquid 14 essentially comprises the first solvent 9 and the soluble components of the raw tobacco 2. The infused tobacco liquid may also contain non-filtered, non-soluble tobacco particles.

The infused tobacco liquid 14 is then heated in a subsequent heating step 16. The infused tobacco liquid 14 is heated to 100-190°C. In this way, the first solvent 9a can be evaporated. By definition, this evaporation of the first solvent 9a includes not necessarily the evaporation of the complete first solvent 9 present in the infused tobacco liquid. Preferably, only a part of the first solvent 9a is evaporated in the heating step 16, wherein a second part of the first solvent remains unevaporated. Alternatively, it is also possible to evaporate the complete first solvent 9 from the infused tobacco liquid 14. In this case the second part of the first solvent 9b is non-existent and the evaporated part of the first solvent 9a equals the total amount of the first solvent 9. By conducting the heating step 16 with the evaporation of the first solvent 9a, a concentrated tobacco liquid 17 is obtained.

The concentrated tobacco liquid 17 is then further heated in a caramelization step 18. In the caramelization step 18 the concentrated tobacco liquid 17 is heated until the caramelization reaction of the reducing sugars present in the raw tobacco material starts. The concentrated tobacco liquid 17 is then heated further until the caramelization occurred to the desired extent. Depending on the temperature to which the concentrated tobacco liquid 17 is heated, it is possible that only certain reducing sugars undergo the caramelization reaction, while other sugars remain uncaramelized. In this caramelization step 18 the preliminary tobacco product 20 is formed. The caramelization step 18 changes the taste profile of the preliminary tobacco product 20 in comparison to the concentrated tobacco liquid 17 in terms of adding a caramel- sweet taste to the preliminary tobacco product 20. The caramelization step 18 further changes the texture of preliminary the tobacco product 20 in comparison to the concentrated tobacco liquid 17. The resulting preliminary tobacco product 20 comprises a syrup-like, jam-like and/or honey-like texture. The preliminary tobacco product 20 comprises a viscosity of 10-100 Pa.s measured at 60°C.

Finally, the dried tobacco material 5 is mixed with the preliminary tobacco product 20 to obtain the tobacco product 21 , also referred to as the final tobacco product 21 . Preferably, the dried tobacco material 5 and the preliminary tobacco product 20 are mixed in a ratio between 1 :6 and 3:1 .

Figure 2 shows schematic view of an alternative process flow of the method for preparing a preliminary tobacco product 20 and a liquid tobacco solution 22.

The raw tobacco 2 is obtained by a selection and/or mixture of at least one tobacco type 2b, 2c, 2d, 2e. If more than one tobacco type 2b, 2c, 2d, 2e is selected, the different tobacco types are mixed at the desired ratios to form the raw tobacco 2. The different tobacco types 2b, 2c, 2d, 2e can include different species of the nicotiana plant, differently cured tobacco types, other different forms of tobacco types and/or different parts of the tobacco plant.

Before mixing 7 the raw tobacco 2 with the first solvent 9, the raw tobacco 2 can be grinded in a grinding step 4. This results in grinded raw tobacco 6. With the grinding step, the desired maximum particle size can be ensured. The grinded raw tobacco can then be subjected to the very same method for producing a preliminary tobacco product 20 as the raw tobacco 2.

The removal step 12 can be a filtration step. The removal step 12 can be membrane filtration, decantation and/or pressing. The pressing step may be obtained by filter press or centrifuga tion for example.

When subjecting the concentrated tobacco liquid 17 to the caramelization step 18, a Maillard reaction and/or lignin pyrolyze 19 may take place simultaneously.

With the preliminary tobacco product 20, a tobacco liquid solution 22 can be produced. To do so, the preliminary tobacco product 20 obtained by any of the previously described processes is mixed with a second solvent 24 and with the dried tobacco material 5. In other words, the tobacco liquid solution 22 is the tobacco product 21 mixed with a second solvent 24. The sec ond solvent 24 comprises water, propylene glycol and/or glycerol. The tobacco product 20 is diluted with the second solvent 24 in a ratio between 1 :1 and 1 :20. The resulting tobacco liquid solution 22 is aerosolisable. The tobacco liquid solution 22 comprises a total sugar content between 15 and 75 weight %. The tobacco liquid solution 22 comprises caramelized sugar. It further comprises alkaloids (preferably nicotine) and/or essential oils.

Figure 3 shows a schematic view of an alternative process flow of the method for preparing a tobacco product 21 or a liquid tobacco solution 22. In contrast to the previously described process, the liquid tobacco solution 22 is not obtained by simultaneous mixing of the second solvent 24 and the dried tobacco material 5 into the preliminary tobacco product 20. The dried tobacco material 5 is rather mixed with the preliminary tobacco product 20 first thereby creating the tobacco product 21 . Subsequently, the tobacco product 21 is then diluted with the second solvent 24 creating the liquid tobacco solution 22. In alternative to this, the preliminary tobacco product 20 may also be first diluted with the second solvent 24 and then mixed with the dried tobacco material 5. This alternative bears the advantage that the dried tobacco material 5 is easier to mix with the diluted preliminary tobacco product 20 due to a reduced viscosity from mixing with the second solvent 24. Another alternative would be to first mix the dried tobacco material 5 with the second solvent 24 and then add the preliminary tobacco product 20.

The processes shown in figures 2 and 3 comprise optional steps. Optional steps are: obtaining the raw tobacco 2 from mixing different tobacco types 2b-3; the grinding 4 of the raw tobacco 2 to obtain grinded raw tobacco 6 and the Maillard reaction and/or lignin pyrolyze 19. Figure 3 comprises an additional optional step. This optional step is the mixing of the tobacco product 21 with the second solvent 24 for obtaining the tobacco liquid solution 22. If this step is left out, the process will yield the tobacco product 21 without any further solvents instead of the tobacco liquid solution 22. By selecting at least one or even all of the optional steps, the manufacturing process can be tailored to meet specific product specifications.

The applicant reserves his right to claim all features disclosed in the application document as being an essential feature of the invention, as long as they are new, individually or in combi nation, in view of the prior art. Furthermore, it is noted that in the figures features are described, which can be advantageous individually. Someone skilled in the art will directly recognize that a specific feature being disclosed in a figure can be advantageous also without the adoption of further features from this figure. Furthermore, someone skilled in the art will recognize that advantages can evolve from a combination of diverse features being disclosed in one or vari ous figures.

List of reference symbols

2 raw tobacco

2a tobacco material

2b-e tobacco type

3 drying/roasting step

4 grinding step

5 dried tobacco material

6 grinded raw tobacco

7 mixing step

8 tobacco-solvent mixture

9 first solvent

10 infusion step

12 removal step

14 infused tobacco liquid

16 heating step

9a part of first solvent

9b second part of first solvent

17 concentrated tobacco liquid

18 caramelization

19 maillard and/or lignin pyrolyze reaction

20 preliminary tobacco product

21 tobacco product

22 tobacco liquid solution

24 second solvent

Claims

1. Method for preparing a tobacco product (21 ), comprising the steps:

- providing raw tobacco (2) having a content of reducing sugars of at least 4% by weight,

- mixing (7) and infusing (10) the raw tobacco (2) with a first solvent (9),

- removing tobacco material (2a) to obtain an infused tobacco liquid (14),

- heating the infused tobacco liquid (14) thereby evaporating the first solvent (9a) and caramelizing (18) the reducing sugars thereby forming a preliminary caramel ized tobacco product (20),

- drying (3) the removed tobacco material (2a) creating dried tobacco material (5),

- adding the dried tobacco material (5) to the preliminary caramelized tobacco product (20) thereby creating a tobacco product (21 ).

2. Method according to claim 1 characterized in that, a moisture content of the dried tobacco material (5) is between 0 - 15 %, preferably between 0-13 %.

3. Method according to claim 1 or 2 characterized in that, the dried tobacco material (5) and the preliminary tobacco product (20) are mixed in a ratio between 1 :6 and 3:1.

4. Method according to at least one of the preceding claims 1 to 3 characterized in that, during drying (3) the removed tobacco material (2a) is roasted (3a).

5. Method according to claim 4, characterized in that, the roasting (3a) takes place at temperatures between 180°C to 260 °C.

6. Method according to at least one of the preceding claims characterized in that, the raw tobacco (2) comprises a maximum content of reducing sugars of 30 % by weight.

7. Method according to at least one of the preceding claims characterized in that, the viscosity of the caramelized preliminary tobacco product (20) is between 10 Pa.s and 100 Pa.s at 60°C.

8. Method according to at least one of the preceding claims characterized in that, before, after or together with adding the dried tobacco material (5) to the preliminary caramelized tobacco product (20), a second solvent (24) is added to the mixture.

9. Method according to claim 8 characterized in that, the second solvent (24) comprises water, or propylene glycol, or glycerol or combina tions thereof.

10. Method according to any of the claims 8 or 9 characterized in that, the total sugar content is up to 5 wt.%, preferably between 0.1 and 2 wt. %, more preferably between 0.2 and 1 .5 wt. % of the tobacco product (21) comprising the sec ond solvent (24).

11 . Tobacco product (21) characterized in that, it contains at least caramelized tobacco sugar and non-soluble tobacco particles having particles size lower than 2 mm.

12. Tobacco product (21) according to claim 11 , characterized in that, it also comprises a solvent (24).

13. Tobacco product (21) according to claim 12, characterized in that, it comprises a viscosity between 110 to 175 mPa.s at 20°C.

14. An aerosolisable product for an aerosol generation device containing the tobacco prod uct (21) according to any one of claims 11 to 13.

15. A smoking article containing the tobacco product (21) according to any one of claims 11 to 13.

16. A snus or chewing article containing the tobacco product (21) according to any one of claims 11 to 13.