WO2020239621A1

WO2020239621A1 - Reconstituted tobacco processing improvement

Info

Publication number: WO2020239621A1
Application number: PCT/EP2020/064255
Authority: WO
Inventors: Takayuki Miyazaki; Marcel KOERNER; Toshifumi Suzuki
Original assignee: Jt International Sa
Priority date: 2019-05-24
Filing date: 2020-05-22
Publication date: 2020-12-03

Abstract

The present invention relates to a reconstituted tobacco product (80) having an alkaloid content, in particular a nicotine content, lower than 3 % based on dry weight, preferably lower than 1 % based on dry weight, characterized in that it is obtained by a method, comprising the steps of (a) Selecting tobacco materials (10) from tobacco by-products such as tobacco leaf scraps, tobacco stems and stalks, tobacco dust and fines created during tobacco processing, and tobacco leaf prime lamina strip; (b) Slurrying the tobacco materials in a water-based solution (20), thereby producing a pulp (30) having a liquid fraction (40) and a fibrous fraction (50), wherein the liquid fraction (40) contains water-soluble materials comprising alkaloid content extracted from the tobacco materials; (c) Removing said water-soluble materials from the pulp by removing the liquid fraction (40); (d) Refining the tobacco pulp without water-soluble materials (60) and forming a sheet with said tobacco pulp without water-soluble materials; (e) Drying (70) the tobacco pulp without watersoluble materials to form a reconstituted tobacco product (80).

Description

Reconstituted Tobacco Processing Improvement

Technical Field of the Invention

The present invention relates to tobacco, and in particular to processed tobaccos, such as reconstituted tobaccos, and to the use of processed tobaccos in tobacco products, such as smoking articles (e.g., cigarettes, aerosol-generating articles, heat-not-burn products and the likes).

Background of the Invention

Typical smoking consumables, such as cigarettes, have a substantially cylindrical rod-shaped structure and include a charge, roll or column of smokable material such as shredded tobacco circumscribed by a paper wrapper, thereby forming a so-called“tobacco rod”.

During the production and the processing of tobacco products, tobacco by-products can be recycled to reclaim their useful tobacco content. In the past, such tobacco by-products have been formed into what is known in the industry as reconstituted tobacco sheets.

Once the reconstituted tobacco is formed into a flattened sheet form, the reconstituted tobacco sheet can then be cut in a similar manner as whole leaf tobaccos to produce tobacco fillers suitable for cigarettes and other smoking articles.

Document US 20050056294 A1 discloses a modified reconstituted tobacco sheet for use in a cigarette, including up to about 80% by weight of wood pulp, up to about 30% by weight of a binder, and up to about 80% by weight of tobacco. Furthermore, said document discloses in Figure 8 a flow chart showing the production process of the reconstituted tobacco. An aqueous solvent is added to make a solution. The solution is separated into an extract and a solid/fibrous portion. As shown in the Figure 8, the extract portion is added back to the base sheet of the solid fibrous portion. According to the invention, a humectant and a flavour can be firstly added to the extracted portion before adding to the base sheet.

US7900639 discloses reconstituted tobacco containing additive materials (e.g. tocopherol or derivatives thereof). The additive(s) can be incorporated into the aqueous tobacco extract or to the water insoluble pulp. It is further disclosed that in a typical paper-making reconstituted tobacco process, the aqueous tobacco extract that is separated from the pulp is added back to the insoluble pulp, preferably as soon as possible, due to the fact that aqueous tobacco extract that is not recombined with tobacco pulp within relatively short periods of time begins to undergo biological degradation.

Nevertheless, the alkaloid content, in particular nicotine content of the reconstituted tobacco sheet is high due to the fact that most, if not all, of the alkaloid content from the raw tobacco materials can be fully recovered in the reconstituted tobacco sheet due to the production method.

Alkaloid analysis has shown that high levels of nicotine and nornicotine result in an undesirable tobacco product. It has been proven that nicotine and nornicotine are precursors of the carcinogenic e.g. N- nitrosonornicotine, N-nitrosoanatabine, and other tobacco-specific nitrosamines (TSNA). These elements have also been identified in cured tobacco and in smoke. Thus, low total alkaloid levels and amounts of individual components are important for evaluating tobacco products for both potential biological activity and marketing quality.

Due to the increasing health awareness from the public and from the policy makers, there is a need in the market to have lower content of alkaloid and nicotine in the cigarette, especially from the reconstituted tobacco.

Presently, several methods exist for reducing nicotinic alkaloids, such as nicotine, in tobacco plants. For example, a low-nicotine strain of tobacco has been employed, for instance, as breeding stock for low-nicotine cultivars, as discussed in Legg et al. , Crop Sci 10:212 (1970). In addition, genetic engineering methods also can be employed to reduce nicotine levels. However, these methods are time-consuming and not cost effective.

Therefore, a new and simple method for producing reconstituted tobacco product having lower alkaloid and nicotine content is thus envisaged.

Summary of the Invention

The inventors of the present invention have found solutions to the above-discussed problems by improving the manufacturing process of reconstituted tobacco products for it to exhibit a low alkaloid content, in particular low nicotine content.

In a first aspect of the invention, it is provided a reconstituted tobacco product having an alkaloid content, in particular a nicotine content, lower than 3 % based on dry weight, preferably lower than 1 % based on dry weight, characterized in that it is obtained by a method, comprising the steps of (a) Selecting tobacco materials from tobacco by-products such as tobacco leaf scraps, tobacco stems and stalks, tobacco dust and fines created during tobacco processing, and tobacco leaf prime lamina strip; (b) Slurrying the tobacco materials in a water-based solution, thereby producing a pulp having a liquid fraction and a fibrous fraction, wherein the liquid fraction contains water- soluble materials comprising alkaloid content extracted from the tobacco materials; (c) Removing said water-soluble materials and its alkaloid content from the pulp by removing the liquid fraction; (d) Refining the tobacco pulp without water-soluble materials and forming a sheet with said tobacco pulp without water-soluble materials; (e) Drying the tobacco pulp without water- soluble materials to form a reconstituted tobacco product.

In a second aspect of the invention, it is provided a use of the reconstituted tobacco product of the present invention. In a third aspect of the invention, it is provided a smoking article comprising the inventive reconstituted tobacco product.

According to one embodiment of the invention, the alkaloid content of the reconstituted tobacco product is less than about 1 % based on dry weight when no exogenous nicotine-containing material is applied to the dried reconstituted tobacco product. This allows the product to have very low alkaloid content, in particular nicotine, narnicotine and anabasine.

According to another embodiment of the invention, the alkaloid content of the reconstituted tobacco product is less than about 3 % based on dry weight when exogenous nicotine-containing material is applied additionally to the dried reconstituted tobacco product. This allows the product has low alkaloid content, in particular nicotine, nornicotine and anabasine.

According to another embodiment of the invention, the liquid fraction separated from the tobacco pulp is not re-introduced back to the process of manufacturing reconstituted tobacco product. This allows the reconstituted tobacco product to have a very low alkaloid (including nicotine, narnicotine and anabasine) content.

According to another embodiment of the invention, the method further comprises a step of forming the reconstituted tobacco product in form of a sheet.

According to another embodiment of the invention, the method further comprises a step of adjusting sensory characteristic of the reconstituted tobacco product by introducing one or more organic or chemical compounds such as casings, enhancers, humectants, flavouring materials, combustion and ash modifiers to the dried reconstituted tobacco product.

According to another embodiment of the invention, the drying step is carried out before or after the adjusting step. According to another embodiment of the invention, the method further comprises a step of cutting and/or shredding of the reconstituted tobacco product.

According to another embodiment of the invention, the water-based solution is removed from the tobacco pulp through heat vaporization, fractionating treatment, filtration, separation and/or centrifugation.

According to another embodiment of the invention, the removed water-based solution containing extracted water-soluble materials is

concentrated for instance by evaporation for further applications.

Brief Description of the Drawing

Fig. 1 is a flow chart illustrating an exemplary embodiment of a method of producing reconstituted tobacco products.

Detailed Description of the Invention

Figure 1 shows an exemplary embodiment of a method of producing a reconstituted tobacco product according to the present invention. A wide variety types of the tobacco useful for carrying out the present invention can be considered. For instance, tobacco materials 10, including reconstituted tobacco materials, can be derived from various types of tobacco, such as flue-cured tobacco, burley tobacco, Oriental tobacco, Maryland tobacco, dark tobacco, dark-fired tobacco and Rustico tobaccos or blends thereof.

Suitable tobacco materials 10 selected from tobacco by-products, for example tobacco leaf scraps, tobacco stems, tobacco stalks, tobacco dust and fines created during tobacco processing, and tobacco leaf prime lamina strip can be used for the purpose of making reconstituted tobacco product. In a first step, water-based solution 20 such as pure water or tap water, and the tobacco materials selected from tobacco by-products 10 are mixed to form a tobacco pulp 30 (or also known as slurry). In the next step, the mixture of tobacco pulp 30 is subjected to separation conditions to provide the tobacco pulp 30 in a liquid fraction 40 and a fibrous fraction 50.

The liquid fraction 40 contains water-soluble materials such as alkaloid content in particular, which includes nicotine, nornicotine, anatabine, anabasine and other minor elements that are being extracted from the tobacco materials 10. In commercial tobacco, the main alkaloid is nicotine, which accounts for approximately 95% based on dry weight of the total alkaloid fraction. Nornicotine and anatabine are the two most abundant minor alkaloids, present in roughly equal amounts, approximately 2-3% (based on dry weight) each. Anabasine is usually present at a concentration of approximately 0.3% of dry weight of total alkaloids. The tobacco pulp without water-soluble materials (e.g. water- removed tobacco pulp) (fibrous fraction 50) then undergoes a refining process 60 using for instance paper-making type refiners such as disc refiners, conical refiners or the like. As such, the fibrous fraction 50 is subjected to a size reduction step and is refined. The refined, tobacco pulp without water-soluble materials (e.g. water-removed tobacco pulp) can then be transferred to for instance a forming machine comprising a headbox, a continuous fabric or wire mesh belt, and a series of presses.

Thereafter, the refined, tobacco pulp without water-soluble materials 60 can be laid on the fabric or wire mesh belt before subjecting to a drying process 70 in order to form reconstituted tobacco product 80. The reconstituted tobacco product 80 is preferably formed into sheet-like shape. Alternatively before the drying step, the tobacco pulp can be subjected to a cold treatment followed immediately by a heat treatment such that the content of the alkaloid can be extracted more efficiently, thereby producing reconstituted tobacco having alkaloid content less than 3 % or even less than 1 % based on the dry weight. To this end, it is reiterated that it is preferably that the liquid fraction 40 is not re-introduced back to the process of making reconstituted tobacco products such that the low alkaloid content (less than 1 % or less than 3 % based on dry weight if additional exogenous nicotine containing material is added) of the reconstituted tobacco product can be obtained.

The inventors of the present invention have found out that when the tobacco materials 10 is mixed with the water-based solution 20 and soaked, for at least 1 to 24 hours, preferably for at least 6 to 12 hours for instance, almost all alkaloid content, approximately 99 % based on dry weight of the water- soluble alkaloid content can be extracted from the tobacco materials. In other words, only approximately 1 % of dry weight or less of alkaloid content, in particular nicotine content, can be found in base sheet (an intermediate product before the end product of reconstituted tobacco sheet). However, it is noted that the amount of time for the tobacco materials to be mixed with the water-based solution and soaked is not particularly critical in the process and the importance is secondary. It is nevertheless observed that in one preferred embodiment, at least 97 % or at least 99 % based on dry weight of the alkaloid content can be effectively extracted from the tobacco material when the slurred tobacco material (or pulp) is first subjected to a cold treatment followed immediately by a heat treatment. For instance the pulp is chilled at 4 °C for 180 minutes followed by heated to 50 °C for 60 minutes. It is believed that the difference in the temperature causes the cell wall of the tobacco material to be destroyed, thereby allowing the released of the alkaloid content more effectively.

Nevertheless, care has to be given not increase the temperature too high (e.g. over 60 °C where other tobacco compounds which are heat sensitive may be destroyed by the higher temperature.

A number of methods can be used to measure the levels of alkaloid content which remained in the fibrous fraction. The alkaloid content can be extracted from the fibrous fraction using methods known in the art. For example, the extraction method described in“Determination of Nicotine-Related Alkaloids in Tobacco and Cigarette Smoke by GC-FID” by L.Q. Sheng et al. , published online on June 15, 2005 in Chromatographia can be used in the present invention. For instance, the tobacco materials from the fibrous fraction can be dried for 4 h at 40°C in an oven, ground to 40-mesh powder, and 500 mg powder was weighed into a conical flask. NH3-H2O solution (6%, prepared by mixing concentrated aqueous ammonia solution and water in 1 :4 (v/v) ratio; 1.0 ml_) and quinaldine (internal standard, 1.0 mg ml_) in extracting solvent; 1.0 ml_) were added, then 20 mL extracting solvent, prepared by mixing CFhOH and CH2CI2 in 1 :3 (v/v) ratio. After sonication 15 min in an ultrasonic bath, a portion of the extract was filtered into an auto sampler vial for analysis.

Qualitative analysis by gas chromatography-mass spectrometry (GC-MS) can be performed with an HP-5890 gas chromatograph coupled to an HP-5971 mass detector with electron impact source.

Quantitative analysis can be performed with an HP-6890 (Plus+) gas chromatograph equipped with an FID detector and an auto sampler (HP-7683). Chromatograms can be recorded and data can be processed by means of an HP-chemstation.

The reconstituted tobacco product may have tobacco fibre material as a core and the nicotine adsorbed onto the tobacco fibre material or absorbed into the tobacco fibre material, such as by spraying the nicotine onto the tobacco fibre material. If nicotine is sprayed, it is essential to make sure that the total nicotine content in the reconstituted tobacco product is less than 3 % of dry weight.

Additionally, the tobacco and/or the fibres from tobacco may be encapsulated into non-woven materials, well-known for a person skilled in the art. The tobacco product may also comprise one or more additives selected from the group consisting of natural, natural identical, synthetic and semisynthetic additives such as menthol, bergamot, orange, mandarin, acai berry, eucalyptus and coffee, citrus or other fruit flavour, liquorice, etc. Throughout the forthcoming description of the invention, the term "tobacco" refers to any part of a tobacco plant or mixtures of tobacco plants arising from the same or different species as well as being genetically modified (GMO). The tobacco plant belongs to the family Solanaceae and the genus Nicotiana. Examples of parts are leaves, stems, roots etc., which may be obtained by any method such as being fresh, frozen, deep-frozen, freeze dried or cured.

In the context of the present invention, the terms“exogenous nicotine-containing material” shall be construed as any nicotine-containing material not directly deriving from the processed tobacco materials throughout steps (a) to (e) of the manufacturing method of the inventive reconstituted tobacco product as claimed and described herein.

Likewise, by“about” or“approximately” in relation to a given numerical value, it is meant to include numerical values within 10% of the specified value.

Claims

1. A reconstituted tobacco product (80) having an alkaloid content, in

particular a nicotine content, lower than 3 % based on dry weight, preferably lower than 1 % based on dry weight, characterized in that it is obtained by a method, comprising the steps of a. Selecting tobacco materials (10) from tobacco by-products such as tobacco leaf scraps, tobacco stems and stalks, tobacco dust and fines created during tobacco processing, and tobacco leaf prime lamina strip; b. Slurrying the tobacco materials in a water-based solution (20), thereby producing a pulp (30) having a liquid fraction (40) and a fibrous fraction (50), wherein the liquid fraction (40) contains water-soluble materials comprising alkaloid content extracted from the tobacco materials; c. Removing said water-soluble materials from the pulp by removing the liquid fraction (40); d. Refining the tobacco pulp without water-soluble materials (60) and forming a sheet with said tobacco pulp without water-soluble materials; e. Drying (70) the tobacco pulp without water-soluble materials to form a reconstituted tobacco product (80).

2. The product according to claim 1 , wherein the alkaloid content of the

reconstituted tobacco product is less than about 1 % based on dry weight when no additional exogenous nicotine-containing material is applied to the dried reconstituted tobacco product.

3. The product according to claim 1 , wherein the alkaloid content of the

reconstituted tobacco product is less than about 3 % based on dry weight when exogenous nicotine-containing material is applied additionally to the dried reconstituted tobacco product.

4. The product according to any one of the preceding claims, wherein the reconstituted tobacco product (80) does not contain the removed liquid fraction (40) through subsequent reintroduction of the removed liquid fraction (40) or through other methods.

5. The product according to any one of the preceding claims, further

comprising a step of forming the reconstituted tobacco product in form of a sheet.

6. The product according to any one of the preceding claims, further

comprising a step of adjusting sensory characteristic of the reconstituted tobacco product by introducing one or more organic or chemical compounds such as casings, humectants, flavouring materials, combustion and ash modifiers to the dried reconstituted tobacco product.

7. The product according to any one of the preceding claims, wherein the drying step is carried out after the adjusting step.

8. The product according to any one of the preceding claims, further

comprising a step of cutting and/or shredding of the reconstituted tobacco product.

9. The product according to any one of the preceding claims, wherein the water-based solution is removed from the tobacco pulp through heat vaporization, fractionating treatment, filtration, separation and/or centrifugation.

10. Use of the reconstituted tobacco product according to any one of the preceding claims for smoking.

1 1 . A product for smoking comprising a reconstituted tobacco product

according to any one of the claims 1 -9.