阅读说明：本技术 制造烟草提取物的方法 (Method for producing tobacco extract ) 是由 杰夫·福斯-史密斯 海伦娜·迪加 玛丽娜·辛特秋列瓦 于 2018-05-09 设计创作，主要内容包括：本发明提供了一种制造烟草提取物的方法,包括；(a)使烟草与提取溶剂接触,使得烟草成分被从烟草提取到溶剂中,其中提取溶剂包括超临界流体；(b)从包含烟草成分的提取溶剂分离残留的烟草固体；(c)在容器中提供萃取剂,使包含烟草成分的提取溶剂暴露于该容器中的条件,其中容器中的条件使得提取溶剂处于亚临界,从而从提取溶剂中释放烟草成分,并且其中,萃取剂溶解从提取溶剂释放的烟草成分。(The present invention provides a method of making a tobacco extract comprising; (a) contacting tobacco with an extraction solvent such that tobacco constituents are extracted from the tobacco into the solvent, wherein the extraction solvent comprises a supercritical fluid; (b) separating residual tobacco solids from the extraction solvent comprising tobacco components; (c) providing an extraction agent in a container, exposing an extraction solvent comprising a tobacco component to conditions in the container, wherein the conditions in the container are such that the extraction solvent is subcritical, thereby releasing the tobacco component from the extraction solvent, and wherein the extraction agent dissolves the tobacco component released from the extraction solvent.)

1. A method of making a tobacco extract comprising;

step (a) contacting tobacco with an extraction solvent such that tobacco constituents are extracted from the tobacco into the extraction solvent, wherein the extraction solvent comprises a supercritical fluid;

step (b) separating residual tobacco solids from the extraction solvent comprising the tobacco component;

step (c) providing an extraction agent in a container, exposing the extraction solvent comprising the tobacco component to conditions in the container, wherein the conditions in the container are such that the extraction solvent is subcritical, thereby releasing the tobacco component from the extraction solvent,

and wherein the extraction agent dissolves the tobacco constituents released from the extraction solvent.

2. The method of claim 1, wherein the extraction solvent comprises carbon dioxide.

3. The method of claim 2, wherein, during step (a),

a temperature in the range of about 308K to 473K, preferably in the range of 328K to 350K; and is

The pressure is in the range of about 8Mpa to 85Mpa, preferably 20Mpa to 30 Mpa.

4. A process according to any one of the preceding claims, wherein the extractant comprises an aerosol generating agent.

5. A process according to claim 4, wherein the extractant comprises a polyol, such as glycerol and/or propylene glycol.

6. The method of any one of the preceding claims, wherein the tobacco component comprises nicotine and one or more of tobacco flavors and flavors.

7. The method of any one of the preceding claims, further comprising the step of providing the extractant comprising dissolved tobacco constituents in a cartridge, wherein the cartridge is configured for use in a smoking article.

8. A tobacco extract obtainable by the method according to any one of claims 1 to 6.

9. A cartridge configured for use in a smoking article, the cartridge comprising the tobacco extract of claim 8.

10. A smoking article comprising the tobacco extract of claim 8.

11. Use of a tobacco extract obtained by the method according to any one of claims 1 to 7, for generating an inhalable aerosol.

12. Use according to claim 11, wherein the tobacco extract is used in a smoking article.

Technical Field

The present invention relates to a method for producing a tobacco extract and to the tobacco extract obtained by this process. The invention also provides a cartridge for a smoking article comprising a tobacco extract, and the smoking article comprises a tobacco extract.

Background

Tobacco material is heated in smoking articles for the purpose of releasing substances contained in the material and expelling these substances as aerosols.

Smoking articles such as cigarettes, cigars and the like burn tobacco during use to produce tobacco smoke. Attempts have been made to provide alternatives to those tobacco-burning products by producing products that release compounds without burning. An example of such a product is a heating device that releases a compound by heating a material, rather than burning the material. The material may be, for example, tobacco or other non-tobacco products, which may or may not contain nicotine.

Electronic cigarettes or "e-cigarettes" are additional products that have been proposed as alternatives to combustible products. These devices contain a volatizable solution that produces an inhalable aerosol when heated. These solutions may contain components of tobacco. Therefore, it is useful to be able to selectively extract tobacco components.

EP1915064 describes a process for manufacturing reconstituted tobacco comprising a tobacco extraction step. The extraction process uses supercritical carbon dioxide to extract the tobacco components and then contacts the supercritical carbon dioxide containing tobacco components with propylene glycol. The tobacco components are transferred to propylene glycol. Carbon dioxide is always supercritical.

Disclosure of Invention

According to a first aspect of the present invention, there is provided a method of making a tobacco extract, comprising;

(a) contacting tobacco with an extraction solvent such that tobacco constituents are extracted from the tobacco into the solvent, wherein the extraction solvent comprises a supercritical fluid;

(b) separating residual tobacco solids from the extraction solvent comprising tobacco components;

(c) disposing an extraction agent in a vessel, exposing an extraction solvent comprising a tobacco component to conditions in the vessel, wherein the conditions in the vessel cause the extraction solvent to be subcritical, thereby releasing the tobacco component from the extraction solvent,

and wherein the extraction agent dissolves tobacco constituents released from the extraction solvent.

The inventors have determined that variations in the extraction process using supercritical extraction solvents result in variations in the composition of the tobacco extract and/or variations in the physical properties of the extract.

The presence of the extractant results in a tobacco extract that is immediately suitable for use in e-cigarettes and the like. The transition to subcritical conditions allows for efficient and effective separation of tobacco components and extraction solvent. This means that the concentration of tobacco components in the extractant (i.e. in the tobacco extract) is higher and the chemical composition is different compared to the process of EP1915064, where the extraction solvent is always supercritical. This improves the organoleptic properties of the extract.

For processes in which the extraction solvent is made supercritical at all times, it is also advantageous to use subcritical conditions for the separation, since less energy is required to maintain such conditions. The process is therefore more energy efficient, cheap to run and faster to build.

In some cases, the extraction agent comprises an aerosol generating agent. In certain instances, the extractive agent consists essentially of or consists of one or more aerosol generating agents.

In some cases, the extraction solvent used in the above process comprises carbon dioxide. In some cases, the extraction solvent consists essentially of carbon dioxide or consists of carbon dioxide.

In some cases, the extractant used in the above process comprises a polyol. In some cases, the extractant comprises glycerol and/or propylene glycol. In some cases, the extractant consists essentially of glycerol or consists of glycerol.

In certain instances, the tobacco components extracted by the methods described herein include nicotine and one or more of tobacco flavors and flavors.

In certain instances, the methods described herein can further include the step of disposing an extraction agent comprising a dissolved tobacco constituent (i.e., tobacco extract) in a storage cartridge, wherein the storage cartridge is configured for smoking the article.

In some cases, steps (a) and (c) are performed in separate vessels. Step (a) may be accomplished in a first vessel (or extraction vessel) that is maintained at a temperature and pressure at all times that the extraction solvent is supercritical. Step (c) may be accomplished in a second vessel (or separation vessel) that is always maintained at a temperature and pressure that makes the extraction solvent subcritical. In certain instances, step (b) comprises transferring the extraction solvent comprising the tobacco component from the extraction vessel to a separation vessel.

According to a second aspect of the present invention there is provided a tobacco extract obtained or obtainable by a method as described herein.

According to a further aspect, there is provided a cartridge configured for smoking articles, the cartridge comprising a tobacco extract obtained or obtainable by a method as described herein. The cartridge may be configured for an e-cigarette.

According to a further aspect, there is provided the use of a tobacco extract obtained or obtainable by a method as described herein to generate an inhalable aerosol. In some instances, tobacco extracts are used in smoking articles to generate inhalable aerosols.

According to a further aspect, there is provided a smoking article comprising a tobacco extract obtained or obtainable by a method as described herein. In some instances, the smoking article may contain tobacco extract in an insertable storage cartridge configured for use with the smoking article. The smoking article may additionally comprise a mouthpiece. The smoking article may additionally comprise a heater for volatilising an extraction agent comprising the tobacco extract in use.

The smoking article may be an electronic cigarette.

Further features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, given by way of example only.

Detailed Description

For the avoidance of doubt, the term "tobacco extract" as used herein relates to an extractant (entercomponent solvent) comprising a tobacco extract.

A supercritical fluid is any substance having a temperature and pressure above its critical point at which there is no significant liquid or vapor phase present. Supercritical fluids can flow like gases through solids and dissolve materials like liquids. Supercritical fluids have a higher fluid density and therefore a higher dissolving capacity than gases.

In some cases, one or more flavorings can be added to the tobacco extract. As used herein, the term "flavoring" refers to a material that can be used to produce a desired taste or aroma in a product for an adult consumer, as permitted by local regulations. They may include extracts (e.g., licorice, hydrangea, japanese white bark yulan leaf, chamomile, fenugreek, clove, menthol, japanese mint, anise, cinnamon, herb, wintergreen, cherry, berry, peach, apple, scotch whisky, bourbon whisky, scotch whisky, spearmint, peppermint, lavender, cardamom, celery, west indian balsam, nutmeg, sandalwood, bergamot, geranium, honey essence, rose essential oil, vanilla, lemon oil, orange oil, cassia seed, caraway, cognac, jasmine, ylang-ylang, sage, fennel, capsicum, ginger, fennel, coriander, coffee or any kind of mint oil from the genus mentha), flavour enhancers, bitter receptor site blockers, sensory receptor site activators or stimulants, sugars and/or sugar substitutes (such as sucralose, acesulfame potassium, aspartame, saccharin, cyclamate, lactose, sucrose, glucose, fructose, sorbitol or mannitol), and other additives, such as charcoal, chlorophyll, minerals, botanicals or breath fresheners. They may be imitation, synthetic or natural ingredients or mixtures thereof. They may be in any suitable form, for example oil, liquid or powder.

As used herein, an "aerosol generating agent" is an agent that promotes the generation of an aerosol when heated. The aerosol generating agent may facilitate aerosol generation by facilitating initial evaporation and/or condensation of the gas into an inhalable solid and/or liquid aerosol.

In general, suitable aerosol generating agents include, but are not limited to: polyols such as sorbitol, glycerol and dialkyl alcohols (e.g., propylene glycol or triethylene glycol); non-polyhydric alcohols (such as monohydric alcohols), high boiling hydrocarbons, acids (such as lactic acid), glycerol derivatives, esters (such as diacetin, triacetin, triethylene glycol diacetate, triethyl citrate or tetradecanoates (including ethyl myristate and isopropyl myristate), and aliphatic carboxylic acid esters (such as methyl stearate, dimethyl dodecanedioate and dimethyl tetradecanoate)). In some cases, the aerosol generating agent comprises one or more of glycerol, propylene glycol, glyceryl triacetate and isopropyl myristate, suitably glycerol and/or propylene glycol.

The weight ratio of aerosol generating agent to tobacco (dry weight) may be from about 2:1 to about 1:3, suitably from about 3:2 to about 1:2, suitably about 1: 1.

The method according to the invention may additionally comprise an initial step of adding water to the tobacco. The amount of water added may be from about 2% to about 20%, suitably from about 2%, 5% or 8% to about 12%, 15%, 18% or 20% based on the dry weight of the tobacco. This pretreatment with water increases the transfer of polar tobacco components (such as flavors) from the tobacco to the extraction agent.

In the process according to the invention, the higher pressure under supercritical conditions increases the dissolving capacity and increases the extraction efficiency. However, more energy is required to achieve and maintain the higher pressure. Therefore, the supercritical conditions are appropriately selected to balance these conflicting requirements. Where the supercritical fluid comprises carbon dioxide, in some cases the pressure at which extraction occurs may be from about 8MPa, 10MPa, 15MPa, 20MPa or 25MPa to about 85MPa, 70MPa, 55MPa, 40MPa, 30MPa, suitably from 8-85MPa, 15-40MPa or 20-30 MPa. In some cases, the pressure may be from about 10 to 16MPa, suitably about 12MPa, or may be from about 20 to 26MPa, suitably about 23 MPa; the inventors have found that when extraction is completed at these pressures, the concentration of TSNA in the tobacco extract is lower.

In the case where the supercritical fluid comprises carbon dioxide, in some cases the temperature at which extraction occurs may be from about 308K, 318K, or 328K to about 473K, 430K, 390K, or 350K, suitably from 308-.

The transition to subcritical conditions lowers the fluid density of the extraction solvent and thus results in precipitation of tobacco constituents. The conditions must be such that the pressure is below the critical pressure and/or the temperature is below the critical temperature of the extraction solvent. For the thermal efficiency, the conditions are suitably such that the pressure is below the critical pressure of the extraction solvent and the temperature is kept above the critical temperature.

When the conditions are further shifted below the critical point of the extraction solvent, the separation efficiency of the tobacco components and the extraction solvent is improved. However, typically the extraction solvent will be collected and stored after isolation (requiring compression); in some cases, it may be recycled to the extraction chamber. Thus, suitably, the subcritical condition is not well below the critical point to improve energy efficiency. The subcritical conditions are suitably chosen to balance these conflicting requirements. Where the extraction solvent comprises carbon dioxide, in some cases the pressure at which extraction occurs may be from about 3MPa, 4MPa, 5MPa or 5.5MPa to about 7.3MPa, 7MPa, 6.5MPa, 6MPa, 5.5MPa or 5MPa, suitably from 3-7.3MPa, or 4-6 MPa. In the case where the extraction solvent comprises carbon dioxide, in some cases the temperature of the subcritical conditions at which separation occurs may be from about 280K, 300K, 320K, or 330K to about 473K, 430K, 390K, or 350K, suitably from 308-.

Examples of the invention

Analytical method

The water Activity values recorded below were measured at 24.9-25.2 ℃ using a fluid laboratory Water Activity Meter (Aqulab Water Activity Meter). These values were determined using the dew point method.

Viscosity values recorded below were measured at 25 ℃ using a two-seater Rheometer (Gemini Rheometer) from Bohlin Instruments.

Pre-extraction (pretreatment of tobacco)

Ground Virginia tobacco leaves having a particle size ranging from 355 μm to 3.5mm were pretreated by adding water (10% of the total weight of tobacco). After the addition of water, the mixture of tobacco and water was allowed to equilibrate for 15 minutes (this is sufficient time to completely absorb the water).

Pretreated tobacco (1.2kg plus 10 wt% water) was placed in a stainless steel extraction basket, and the basket was placed in an extraction vessel (5L autoclave). The basket is closed at its ends by sintered metal plates (pore size 100 μm, pressure drop across the plate not greater than 1 bar) which distribute the supercritical fluid at the inlet and prevent the solid particles from exiting at the outlet. The use of a basket also allows for rapid loading and discharge of the extraction vessel. The basket is sealed with the extraction vessel wall to prevent flow of supercritical fluid around the extraction vessel wall.

Example 1: examples of the Process according to the invention

The extraction vessel is connected to the separation vessel by a transfer line. There is a pressure regulating valve in the line. Suitably, carbon dioxide can be pumped through the system at a rate of 5-23 kg/hr. In this case, carbon dioxide was pumped through the system at a rate of 10 kg/hr. 1.2kg of glycerol were placed in the separation vessel.

The extraction chamber was maintained at 26MPa and 338K, and the separation chamber was maintained at 4.5MPa and 318K. The extraction of the extract in the separation chamber is achieved by reducing the pressure and temperature (from supercritical to subcritical conditions), which reduces the fluid density of the carbon dioxide and thus the CO₂The dissolving capacity of (c). The extracted tobacco components were collected in glycerol at the bottom of the separator.

Gaseous CO₂Leaves the liquid/gas separator after passing through the separator (which removes any remaining liquid extract entrained in the gas). CO Collection₂And recycled to the extraction chamber.

The process was run for three hours and then the CO was cut off₂And (4) streaming. The system was depressurized (to atmospheric conditions). The glycerol containing tobacco components was then drained from the separation vessel and weighed.

Comparative test

A comparative experiment was performed using the same apparatus as in example 1. However, the apparatus was always in supercritical conditions (26MPa and 338K). All other aspects of the comparative experiment were identical to example 1.

The comparative experiments are representative examples of the process generally described in EP 1915064.

Data of

Tobacco extract characteristics:

the process of example 1 was performed 6 times. Where a range is provided in the data table, all examples are included in the range. The table provides a single number, which is an average number.

It can be seen that the pH of the extract obtained in example 1 was higher than that of the extract obtained in the comparative experiment. This increases the availability of nicotine in solution when using the e-cigarette.

Similar results were observed when oriental or burley starting tobacco was used.

The various embodiments described herein are presented only to assist in understanding and teaching the claimed features. These embodiments are provided merely as representative examples of embodiments 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 construed as limitations on the scope of the invention as defined by the claims or on equivalents to the claims, and that other embodiments may be utilized and modifications may be made without departing from the scope of the claimed invention. Various embodiments of the present invention may suitably comprise, consist of, or consist essentially of, suitable combinations of the disclosed elements, components, features, parts, steps, means, etc., in addition to those specifically described herein. Moreover, the present disclosure may include other inventions not presently claimed, but which may be claimed in the future.