JPH06189732A - Method for treating tobacco raw material - Google Patents

Abstract

PURPOSE:To obtain a method for treating a tobacco raw material in which a desired component can efficiently be extracted from the tobacco raw material without destroying thereof; the tobacco raw material is simultaneously excellent in the quality of aroma and flavor and physical properties can be improved. CONSTITUTION:Carbon dioxide (CO2) in a supercritical state fed from a feeding part 25 is hydrated to a desired moisture content in a hydrating part 30 and then brought into contact with a tobacco raw material filled in an extraction vessel 22 in an extracting and impregnating part 35. Nicotine is extracted and removed from the tobacco raw material with the CO2, which is simultaneously impregnated into the raw material tissue. The CO2 after extracting the nicotine is separated from the nicotine and water in a separating part 40. The CO2 impregnated into the tobacco raw material is instantaneously removed from the tobacco raw material in a puffing treating part 50 to puff the tobacco raw material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention relates to the use of an inactive extractant in a supercritical state to extract and remove soluble matter from a tobacco raw material and impregnate the tobacco raw material with the inactive extractant. The present invention relates to a method for treating a tobacco raw material, which comprises expanding the tobacco raw material by instantaneously removing the extractant from the tobacco raw material.

[0002]

2. Description of the Related Art Conventionally, soluble substances from natural solid raw materials, especially,
As a method for extracting and removing nicotine from a tobacco raw material, for example, the method disclosed in JP-B-51-9838 or JP-A-63-229102 has been proposed. In each of these methods, nicotine is extracted from a tobacco raw material using carbon dioxide (CO ₂ ) in a supercritical state as a solvent.

On the other hand, in order to reduce the amount of raw materials used in tobacco products such as cigarettes and to reduce the flavor and taste of the tobacco products, the tobacco raw materials are subjected to a puffing treatment. The expansion of the tobacco raw material is generally carried out by impregnating the dry expansion-contracted tobacco raw material with the expansion aid and then instantaneously removing the expansion aid from the tobacco tissue by heat treatment or the like. Due to such expansion, the tobacco raw material is expanded to a state close to that of fresh leaves. As the method for expanding the tobacco raw material, the method disclosed in JP-B-47-22800, JP-B-49-1879 and JP-B-51-19039 using an organic solvent as a puffing aid, nitrogen gas is used. The method disclosed in JP-B-59-33346 used, the method disclosed in JP-B-56-3021 using liquid carbon dioxide, or the method disclosed in JP-B-56-50952 using gaseous carbon dioxide. The disclosed method and the like are known.

Further, for example, Japanese Patent Laid-Open No. 3-127975 discloses a method for treating a tobacco raw material including both the extraction step and the expansion step described above. According to this method, CO ₂ in a supercritical state is contacted with a tobacco raw material to extract a soluble component from the tobacco raw material, the tobacco raw material is impregnated with CO _2, and the impregnated CO ₂ is instantaneously removed from the tobacco raw material. To inflate the tobacco raw material,
Next, the soluble component is reduced to a tobacco raw material.

[0005]

[Problems to be Solved by the Invention] Japanese Patent Publication No. 51-9838
In the method for extracting nicotine disclosed in Japanese Patent Publication No. 63-229102 or Japanese Patent Laid-Open No. 63-229102, nicotine can be extracted from a tobacco raw material, but on the other hand, the physical properties (physical properties such as aroma and taste quality or puffiness of a tobacco product produced are ) Could not be satisfied. Further, the above-mentioned Japanese Patent Publication No. 47-22800 and Japanese Patent Publication No.
49-1879, Japanese Patent Publication No. 51-19039, Japanese Patent Publication No. 59-333
46, Japanese Patent Publication No. 56-3021, and Japanese Patent Publication No. 56-50952
The swelling of the tobacco raw material disclosed in the publication can reduce nicotine and tar by reducing the filling amount of the raw material into the cigarette, but the nicotine and tar are reduced from the tobacco raw material itself. There was a limit to what I could do.

Further, according to the method for treating a flavored tobacco raw material disclosed in the above-mentioned JP-A-3-127975, the tobacco raw material is destroyed when the dried and dried tobacco raw material is heated and expanded in the extraction step. May be Also,
When humidifying the raw material in advance to prevent the destruction of the tobacco raw material, the humidification amount cannot be adjusted by the conventional method,
The tobacco raw material may be humidified more than necessary, which makes it difficult to remove the raw material from the extraction container.

The present invention has been made in view of the above points, and an object thereof is to efficiently extract desired components from a tobacco raw material without destroying the tobacco raw material and to improve physical properties such as flavor and taste. An object of the present invention is to provide a method for treating a tobacco raw material which can be improved.

[0008]

According to the method for treating a tobacco raw material of the present invention, a step of supplying water to an inert extractant in a supercritical state and a line mixer for supplying the supplied water and the inert extractant -Mixing with, a step of adding water to the inert extractant, and flowing an inert extractant with added water through the tobacco raw material, while dissolving the soluble matter in the tobacco raw material in the inert extractant , A step of impregnating the tobacco raw material with the inert extractant, a step of separating the soluble matter from the inert extractant in which the soluble matter is dissolved, and the inert extraction from the tobacco raw material impregnated with the inert extractant The step of removing the agent instantaneously and expanding the tobacco raw material, the step of adding includes the step of adjusting the water content of the inert extractant to adjust the water content of the inert extractant. I'm out.

[0009]

According to the above method for treating a tobacco raw material, the moisture content of the inactive extractant is taken into consideration in consideration of the state of the tobacco raw material to be treated, the moisture content or moisture content of the raw material after the extraction treatment, the nicotine content and the like. I am adjusting. That is, the water content of the inert extractant is adjusted by mixing the water whose water supply amount has been adjusted in the adjusting step and the inert extractant with the line mixer. An inactive extractant having a controlled water content is brought into contact with the tobacco raw material to extract the soluble matter, and the tobacco raw material is impregnated with the inert extractant. By instantaneously removing this inert extractant from the tobacco raw material, the tobacco raw material is expanded. On the other hand, in the inactive extractant from which the soluble matter is extracted, the soluble matter and the inactive extractant are separated in the separation step.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a method for treating a tobacco raw material according to the present invention will be described in detail below with reference to the drawings together with a treatment apparatus for implementing this treatment method.

As shown in FIG. 1, a tobacco raw material treating apparatus 10 for carrying out the treatment method according to the present embodiment extracts nicotine from a tobacco raw material and at the same time extracts a desired inert extractant such as carbon dioxide (CO 2). ₂ ) An extraction treatment section 20 for impregnating a tobacco raw material with a tobacco raw material and a puffing treatment section 50 for expanding a tobacco raw material impregnated with CO ₂ . Extraction processing unit 20
Is a supply unit 25 for supplying carbon dioxide (CO ₂ ) in a supercritical state, a water-containing unit 30 for adjusting CO ₂ in a supercritical state to a desired water content, and a supercritical state adjusted to a desired water content. C
An extraction / impregnation unit 35 for extracting nicotine from the tobacco raw material and impregnating the tobacco raw material with CO ₂ by bringing O ₂ into contact with the tobacco raw material, and a nicotine-dissolved CO
_And a separating section 40 for separating nicotine from ₂ , which are connected by a distribution pipe 21 to form the first closed circuit 1.

The supply portion 25 in the first closed circuit 1 is a liquid C.
A liquid storage tank 4 for storing O ₂ is provided, and the liquid storage tank 4 is provided.
Is provided with a jacket 5 having a function of keeping the temperature in the tank constant. On the CO ₂ inflow side of the liquid storage tank 4,
A CO ₂ tank 8 is connected via the booster 6 and the first heat exchanger 7. The outflow side of the liquid storage tank 4 is connected to the inflow side of the static mixer 15 in the water-containing portion 30 via the flow meter 11, the first pump 12, and the second heat exchanger 13. The water-containing portion 30 is a static mixer-15,
The second pump 16 and the water tank 18 are provided, and CO ₂ supplied from the supply unit 25 and water supplied from the water tank are mixed in the static mixer 15.

An extraction / impregnation unit 35 having an extraction container 22 and a jacket 23 is connected to the outflow side of the static mixer 15. An inner cylinder 24 is detachably mounted in the extraction container 22, and a tobacco raw material s is loaded in the inner cylinder.
To the downstream side of the extraction / impregnation section 35, a pressure gauge 26 and a separation section 40 having a separator 32 and a jacket 33 are connected via a first pressure regulating valve 28. The downstream side of the separation section 40 is connected to the liquid storage tank 4 via a pressure gauge 36, a second pressure control valve 38, a gas purification tower 42, and a third heat exchanger 44.

The puffing section 50 is provided with a puffing tube 51 having a second closed circuit 2, through which a tobacco raw material,
A heating medium such as air or a mixed gas of air and water vapor can be circulated. In the second closed circuit 2, a hopper 52 for supplying the tobacco raw material into the expansion tube 51, a fan 53 for circulating the heating medium, a heater 54 for heating the heating medium flowing in the expansion tube 51, and a cigarette. A tangential separator 55 for separating the raw material and the heating medium is provided. Further, the expansion tube 51 is provided with a flow meter 56 for measuring the flow rate of the heating medium and a valve 57. The tobacco raw material expanded in the expansion tube 51 and separated by the tangential separator 55 is sent to the humidity controller 60.

In FIG. 1, T indicates a thermometer.

As shown in FIG. 2, a static mixer
Reference numeral 15 includes a main body pipe 14 having substantially the same diameter as the distribution pipe 21, and a stirring blade 17 arranged in the main body pipe along the axial direction thereof. Each end of the main body pipe 14 has a flange 14a, which is connected to the distribution pipe 21. Thereby, the main body pipe 14 constitutes a part of the distribution pipe 21 through which CO ₂ flows.

The stirring blade 17 is formed by twisting a rectangular plate material 180 degrees in the opposite direction to the first element 17a, which is formed by twisting a rectangular plate material 180 degrees. And three second elements 17b, the first element and the second element
Elements are alternately arranged and are connected to each other at an angle of 90 degrees.

A water supply pipe is provided at the upstream end of the main body pipe 14.
The second pump 16 is connected via 19. The second pump 16 is composed of a variable displacement type fluid pump, and the amount of water supplied to the static mixer 15, that is, the amount of water added can be freely adjusted.

A method of treating a tobacco raw material by using the tobacco raw material treating apparatus 1 configured as described above will be described.

In the supply unit 25, the gas CO ₂ supplied from the CO ₂ tank 8 is compressed by the booster 6 and then
The liquid is cooled in the first heat exchanger 7, liquefied, and stored in the liquid storage tank 4. The state of CO _{2 in} the liquid storage tank 4 may be any condition as long as it is liquid, and other known techniques may be used to store CO ₂ .

When the first pump 12 is operated, CO ₂ flows from the liquid storage tank 4 through the flow meter 11 into the second heat exchanger 13, where it is heated to about 70 ° C. and supercritical. Condition (31.1 ℃
More than 75.3kg / cm ² ). CO _{2 in} supercritical state
Flows into the static mixer 15 of the water containing portion 30. At the same time, the static mixer 15 is supplied with water adjusted to a desired amount by the second pump 16. Therefore, CO
_{The 2} and the water flow together through the static mixer 15, in which case the first element 17a of the stirring blade 17 swirls, for example clockwise, and the second element 17b swivels counterclockwise. . Then, water repeats inversion together with CO ₂ and flows in the static mixer 15 to be mixed and dissolved in CO ₂ , and CO ₂ having a desired water content is discharged from the static mixer 15.

The water content of CO ₂ can be set to a desired value by adjusting the amount of water supplied to the static mixer 15 by the second pump 16. The preferred water content is 50 to 70%, and most preferably 60% of the saturated amount of water dissolved in CO _{2 at} each extraction temperature and extraction pressure. For example, the extraction temperature in the extraction container is 60 ° C and the extraction pressure is 300 kg / cm.
^When extracting under the conditions of ^2, the amount of water added is 1.9 ~
2.7 g / kg-CO ₂ is preferred. The extraction temperature in the extraction container 22 is preferably 50 to 80 ° C, and the extraction pressure is 150 to 80 ° C.
It is preferably 300 kg / cm ² .

Subsequently, CO ₂ in a supercritical state containing water in the water containing portion 30 is supplied to the extraction / impregnation portion 35. In the extraction / impregnation unit 35, the extraction container 22 is formed of a pressure container having a pressure resistance of 300 kg / cm ² , and the tobacco raw material s is contained in the extraction container 22.
Is filled with the inner cylinder 24. Extraction / impregnation part 35
CO ₂ supplied to the raw material flows into the extraction container 22 through the tobacco raw material s, and the nicotine in the tobacco raw material is CO ₂
And is extracted from the tobacco raw material. At the same time, part of the CO ₂ that has come into contact with the tobacco raw material impregnates inside the tobacco tissue. At this time, the temperature in the extraction container 22 is maintained at a temperature that maintains the supercritical state of CO ₂ by the circulating liquid in the jacket 23, and the temperature and pressure in this supercritical state are detected by a thermometer and a pressure gauge, respectively. .

CO ₂ containing nicotine is extracted from the extraction container 22.
Through the first pressure regulating valve 28, and after being decompressed here,
It is supplied to the separation unit 40. The pressure inside the separator 32 is
Is detected by the second pressure adjusting valve 38 and is adjusted to a critical pressure or less by the second pressure adjusting valve 38. The temperature in the separator 32 is detected by a thermometer and adjusted by the circulating liquid in the jacket 33, and is set to be equal to or higher than the saturation temperature at the pressure set by the second pressure adjusting valve 38. Accordingly, CO ₂ that has flowed into the separating portion 40 is in the gaseous in the separator 32, nicotine and water were dissolved in CO ₂ is precipitated from the CO _2, it is separated. The deposited nicotine and water as the extraction substance are stored in the separator 32, and are discharged to the outside of the separator 32 through the valve 34 after or during the extraction process.

The CO ₂ from which the nicotine has been separated is further decompressed by the second pressure adjusting valve 38, and then flows into the gas purifier 42, where the water and volatile components remaining in the CO ₂ are removed. Be refined. The purifier 42 is filled with a filler such as molecular sieve, activated alumina, silica gel, magnesium sulfate and activated carbon. Purified CO
₂ is the third heat exchanger set below the saturation temperature
After being cooled at 44 and liquefied, it is returned to the liquid storage tank 4.

Through the above steps, nicotine is removed from the tobacco raw material s in the extraction container 22 and CO ₂ is impregnated into the tobacco raw material tissue. When the desired amount of nicotine has been extracted, the valve 27 is adjusted to reduce the pressure in the extraction container 22 to atmospheric pressure. The time required for this pressure reduction is usually 5 seconds to 120 minutes. After the depressurization, the tobacco raw material s is taken out from the extraction container 22 together with the inner cylinder 24 and transferred to the expansion processing section 50.

The expansion processing section 50 is composed of an airflow dryer. The temperature of a heating medium such as air or a mixed gas of air and water vapor is adjusted by a heater 54, and a fan 53 inserts it into the expansion tube 51. It is circulated. C at the extraction / impregnation part 35
The tobacco raw material s impregnated with O ₂ is expanded from the hopper 52 to the expansion tube 51.
It is supplied to the inside, is conveyed by a heating medium, and is heated in the expansion tube 51. At this time, the CO ₂ impregnated in the structure of the tobacco raw material is instantly vaporized by heating and released from the tobacco raw material, whereby the tobacco raw material is expanded.

The puffed tobacco raw material is separated from the heating medium by a tangential separator 55,
It is supplied to the humidity controller 60. The heating medium is usually set to 100 ° C or higher, preferably 125 ° C to 280 ° C. The circulation speed of the heating medium is controlled by the valve 57 and the flow meter 56, and the time for which the tobacco raw material is conveyed to the tangential separator 55 by controlling this flow rate is 0.5 to 20 seconds. , Preferably 1 to 5 seconds. Further, the puffing process is performed as quickly as possible within 20 seconds to 5 minutes after the tobacco raw material is taken out after the pressure is released to the atmospheric pressure in the extraction container 22.

The tobacco raw material used in the above-mentioned tobacco raw material treating step may have any shape, but is preferably a chopped shape which is easy to carry out later. Further, the water content of the tobacco raw material supplied to the puffing section 50 after extracting nicotine is 5 to 100% DB, preferably 8 to 30% DB. If the water content is 5% or less, the tobacco raw material s may be destroyed in the expansion treatment section 50.

As described above, the extraction / impregnation unit 35 separates the extraction container 22 from the extraction container 22 while supplying CO ₂ to the extraction container 22.
The CO ₂ by continuously derived, the extraction vessel 22 is used flow scheme of impregnating the CO ₂ in the tobacco material tissue is extracted remove nicotine from left tobacco material was maintained in a supercritical state. In this flow-through method, the flow rate of CO ₂ required to extract soluble components such as nicotine is measured by the flow meter 11 and expressed as a weight ratio (extractant ratio) with the tobacco raw material with which the extraction container 22 is filled. , 0.1 to 1000k
GCO ₂ / kg time is controlled to preferably be 300kgCO ₂ / kg time from 30. Further, when it is desired to obtain a tobacco raw material having an arbitrary nicotine content such that almost all nicotine in the tobacco raw material is removed, an arbitrary extraction agent ratio can be used regardless of the above extraction agent ratio.

Although the pressure in the extraction container 22 is released to the atmospheric pressure when the tobacco raw material is taken out from the extraction container 22, a plurality of extraction containers are used in order to reduce the emission of CO ₂ to the atmosphere as much as possible. ligated, after contact of the CO ₂ and tobacco material is completed, the process can be operated efficiently CO ₂ by introducing the CO ₂ in the extraction vessel 22 ended another extraction vessel.

The present inventors conducted the following tests in order to examine the nicotine content, the filling effect, the flavor and the like of the tobacco raw material processed using the above-mentioned tobacco raw material processing system. The internal volumes of the extraction container and the separator used in this test example are each 4 liters.

(Test 1) 300 g of a domestic yellow seed (bright yellow) tobacco raw material having a water content of 14% DB is filled in the inner cylinder 24, and the inner cylinder 24 is loaded in the extraction container 22. Jacket
The temperature of the extraction container 22 is maintained at 70 ° C by passing the circulating liquid through 23,
Set the first pressure regulating valve 28 to 250 kg / cm ² G. on the other hand,
The temperature of the separator 32 is maintained at 20 ° C. by circulating the circulating liquid through the jacket 33, and the second pressure regulating valve 38 is set at 50 kg / cm ² G. Then, CO ₂ in a supercritical state is supplied to the first closed circuit 1.
Water was supplied at a rate of 250 g / min, and water was added at a rate of 0.683 g / min to CO ₂ through a static mixer-15. The added amount corresponds to 60% of the saturated dissolution amount in CO _{2 at} 250 kg / cm ² G and 70 ° C.

When the extraction unit 20 is operated under the above set conditions and the amount of CO ₂ passing through the extraction container 22 is 150 times the weight of the tobacco raw material, that is, 45 kg is supplied, the first pump 12
And the supply of CO ₂ was stopped.

After the extraction of nicotine is completed, the pressure inside the extraction container 22 is reduced by reducing the pressure of the first pressure regulating valve 28.
_By rapidly returning ₂ to the liquid storage tank 4 and opening the valve 27, the time for reducing the pressure in the extraction container 22 to the atmospheric pressure is shortened. Then, after the pressure inside the extraction container 22 was reduced to the atmospheric pressure, the inner cylinder 24 filled with the tobacco raw material was immediately taken out, and the following expansion process was performed by the expansion process section 50.

In the expansion tube 51 of the expansion processing section 50, a heating medium having a volume ratio of steam of 90% and a temperature of 260 ° C. is caused to flow, and the tobacco raw material taken out from the inner cylinder 24 is charged from a hopper 52. After 2 seconds, separation was performed with a tangential separator 55, and the expanded tobacco raw material from which nicotine was removed was taken out.

As a result of the above test, the nicotine content of the untreated tobacco raw material was 3.40% DM, whereas the nicotine content of the tobacco raw material after treatment was 0.68% DM, and 80% nicotine could be removed. It was Then, the tobacco raw material after the above treatment was allowed to stand in a conditioning room at a temperature of 22 ° C. and a relative humidity of 60%, and after 24 hours, the filling effect was measured with a bladder measuring instrument, which was 1.66 times that of the untreated tobacco raw material. It was. Furthermore, as a result of a sensory test by 10 specialized panelists, the flavor and taste of the tobacco material from which nicotine was removed obtained in the above test was evaluated as +1 compared with the untreated tobacco material as a control product. there were.

The sensory test by the above-mentioned specialized panelist was conducted on the basis of the untreated tobacco raw material of the control product, and the nicotine-free puffed tobacco raw material obtained as described above was relaxed (easy to suck). ) Is evaluated by the three-point comparison method. That is, +1 for those that are slightly superior to the control product, +2 for those that are quite excellent, +3 for those that are extremely excellent, -1 for those that are slightly inferior, -2 for those that are extremely inferior. The inferior one was evaluated as -3.

(Test 2) The pressure in the extraction container 22 was set to 300 kg / c.
m ² , CO ₂ flow rate 320g / min, water addition amount 0.914g / min
As the test, the same operation as in Test 1 was performed except that nicotine was removed and CO ₂ was impregnated by using 200 times as much as the filled tobacco raw material, that is, 60 kg of CO ₂ in a supercritical state.

Nicotine removal rate is 91%, filling effect is 1.72
The flavor evaluation was +2.

(Test 3) A commercially available tobacco blend is used as a tobacco raw material, and the pressure in the extraction container 22 is set to 250 k.
g / cm ² , CO ₂ flow rate 250 g / min, water addition amount 0.569 g / m
As in, the same operation as in Test 1 was carried out except that nicotine was removed and CO ₂ was impregnated by using 300 times as much CO ₂ in a supercritical state as that of the filled tobacco raw material, that is, 90 kg.

The removal rate of nicotine is 89%, and the filling effect is 1.91.
The flavor evaluation was +3.

As described above, according to the method for treating tobacco of the present invention, the supercritical CO ₂ hydrated by the static mixer 15 to a desired water content is brought into contact with the tobacco raw material to remove nicotine or the like from the tobacco raw material. Soluble components are extracted and removed, and CO ₂ is impregnated into the structure of the tobacco raw material. Then, by exposing the tobacco raw material impregnated with CO ₂ and adjusted to a desired water content to the condition that CO ₂ is vaporized, the tobacco raw material in which CO ₂ is instantaneously removed from the tobacco raw material is expanded. When extracting and removing nicotine from a tobacco raw material, since the water content of the tobacco raw material is adjusted to an appropriate value, the tobacco raw material is not excessively dried and destroyed when the tobacco raw material is expanded. Therefore, it is possible to obtain a puffed tobacco raw material having a good flavor and flavor quality and excellent physical properties.

The present invention is not limited to the above-described embodiments, but can be variously modified within the scope of the present invention. For example, although carbon dioxide in a supercritical state was used as the extractant in the above examples, other inert extractants may be used.

[0045]

As described above, according to the method for treating a tobacco raw material of the present invention, since the water content of the inactive extractant is adjusted to a desired value by the static mixer, the desired ingredient is selected from the tobacco raw material. Can be efficiently extracted,
The water content of the tobacco raw material from which the soluble matter is extracted can be adjusted to a desired value. Therefore, the tobacco raw material can be expanded without being destroyed, and the tobacco raw material having high physical properties such as flavor and taste quality can be obtained.

[Brief description of drawings]

FIG. 1 is a schematic view showing a processing apparatus for carrying out the method for processing a tobacco raw material according to the present invention.

FIG. 2 is a schematic view showing a static mixer that constitutes a water-containing portion of the above apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... 1st closed circuit 2 ... 2nd closed circuit 4 ... Liquid storage tank 10 ... Tobacco raw material processing apparatus 15 ... Static mixer-17 ... Stirring blade 22 ... Extraction container 24 ... Inner cylinder 25 ... Supply part 28 ... 1 pressure adjusting valve 30 ... water containing part 32 ... separator 35 ... extraction / impregnation part 38 ... second pressure adjusting valve 40 ... separation part 50 ... expansion processing part 51 ... expansion tube

Front page continued (72) Inventor Manabu Takeuchi 6-2 Umegaoka, Midori-ku, Yokohama-shi, Kanagawa Japan Tobacco Inc. Tobacco Central Research Institute

Claims (1)

[Claims] 1. A step of supplying water to an inactive extractant in a supercritical state, a step of mixing the supplied water and the inactive extractant with a line mixer, and adding water to the inactive extractant. A step of flowing an inert extractant to which water has been added through the tobacco raw material to dissolve the soluble matter in the tobacco raw material in the inert extractant and impregnating the tobacco raw material with the inert extractant, A step of separating the soluble matter from the inert extractant having dissolved the melt, a step of instantaneously removing the inert extractant from the tobacco raw material impregnated with the inert extractant, and expanding the tobacco raw material; The method for treating a tobacco raw material, characterized in that the adding step includes a step of adjusting the amount of water supplied to the inert extractant to adjust the water content of the inert extractant.