JPH0659199B2 - How to puff tobacco material - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for expanding a tobacco raw material.

[Conventional technology and problems]

Tobacco puffing reduces the amount of tobacco raw materials used in tobacco products such as cigarettes, and also reduces the flavor and taste of tobacco products. It is an inflating technology and is an important technology in the manufacture of tobacco products.

The method for expanding the dry tobacco material is basically
Including a puffing aid in the dry tobacco tissue and instantaneously expelling the puffing aid from the tobacco tissue by heating.
The swelling aid, which has been expanded in volume by heating, expands the tobacco raw material.

As a method for expanding the tobacco raw material, a method is known in which the tobacco raw material is impregnated with an organic solvent as a expansion aid in a liquid or gaseous state, and the organic solvent permeated into the tobacco tissue is heated and evaporated (for example, Japanese Patent Publication No. 47-2280
No. 0, No. 49-1879, No. 52-3060.
No. 0, JP 61-15676, etc.). These methods are satisfactory with respect to the swelling rate of cigarettes, but they are costly depending on the solvent used and may adversely affect the flavor and taste of cigarettes.

A method using liquefied carbon dioxide as a swelling aid is also known (Japanese Patent Publication Nos. 53-29000 and 56-302).
1, JP-A-56-50830, JP-A-55-1.
No. 65793), this method includes a step of impregnating a tobacco tissue with liquid carbon dioxide under a considerably high pressure, converting the impregnated liquid carbon dioxide into solid carbon dioxide, and then evaporating the solid carbon dioxide. Therefore, there is a problem that the soluble components in the tobacco raw material flow out and the temperature at the time of heat expansion is high, which adversely affects the flavor and taste.

On the other hand, a method of using gaseous carbon dioxide as a swelling aid is disclosed in JP-B-56-50952.
According to this method, a tobacco raw material is impregnated with gaseous carbon dioxide under a high pressure condition, the pressure is released, and then the tobacco raw material is rapidly heated to expand the tobacco raw material. The pressure when impregnating gaseous carbon dioxide is described as 17.6 kg / cm ² or more, but practically, it is about 28 to 56 kg / cm ^2, especially 40 kg / c ^2.
It has been found to be ineffective without using pressures above m ² . Further, the temperature at the time of heat expansion is set to 100 to 370 ° C., but it has been found that a sufficient expansion rate cannot be obtained unless a temperature exceeding 250 ° C. is actually used.
When the tobacco raw material is treated at such a high temperature, the tobacco raw material burns and the aroma and flavor of the tobacco product are adversely affected even in a short time.

Therefore, the main object of the present invention is to obtain a sufficiently high expansion rate even under conditions where the temperature during heat expansion is relatively low, and to expand the tobacco raw material without adversely affecting the flavor and taste of the tobacco. Is to provide a method.

Another object of the present invention is to provide a method for expanding a tobacco raw material, in which the pressure during impregnation of gaseous carbon dioxide is relatively low and the time can be shortened.

[Means for solving problems]

In the present invention, the tobacco raw material is first impregnated with ethanol, and thereafter the carbon dioxide gas is impregnated with the carbon dioxide gas in the pressure vessel. Then release the pressure in the pressure vessel,
When the obtained ethanol-carbon dioxide gas-impregnated tobacco raw material is subjected to heat treatment to remove ethanol and carbon dioxide, the tobacco raw material swells.

We can obtain a sufficiently high expansion rate even under relatively low carbon dioxide gas impregnation pressure, relatively short carbon dioxide gas impregnation time, and / or relatively low heat expansion and temperature conditions, An intensive study was conducted to develop a method for expanding a tobacco raw material without adversely affecting the flavor and taste of tobacco. As a result, if the tobacco raw material is first treated with ethanol, which has a good affinity for water and a higher solubility of carbon dioxide gas than water, it is dissolved in ethanol in the tobacco tissue and impregnated with carbon dioxide gas. Even if carbon gas impregnation is carried out at low pressure for a short time and / or subsequent heat expansion treatment at low temperature, it is possible to achieve a high expansion rate that cannot be obtained with ethanol alone or carbon dioxide gas alone. The inventors have completed the present invention by finding that they can be expanded without adversely affecting them.

The tobacco raw material to be puffed by the method of the present invention,
These include yellow varieties, burley and other types of tobacco leaves, middle bones and the like, which are preferably pre-cut so that they do not need to be cut after the expansion process. Tobacco ingredients are
It usually contains water in a proportion of 5% to 30% by weight. Practically, the water content of the tobacco raw material is preferably 8% by weight to 23% by weight, although it depends on the expansion conditions described below.

In the method of the present invention, the tobacco raw material is first impregnated with ethanol. This ethanol impregnation can be performed by immersing the tobacco raw material in ethanol or by spraying the tobacco raw material with ethanol. After dipping or spraying with ethanol, the tobacco raw material is taken out of the dipping bath or spraying is stopped, and the ethanol is allowed to stand in the tobacco tissue for 1 minute to several hours, preferably within 1 hour under a temperature and an atmosphere in which ethanol does not evaporate as much as possible. Infiltrate. This leaving time of 1 hour or less is sufficient. Ethanol is preferably 8% DB to 3 in consideration of the ratio of 4% DB (dry base) to 100% DB based on the weight of the dry tobacco raw material, and economical efficiency.
It is preferably impregnated at a rate of 0% DB. This ethanol impregnation concentration can roughly correspond to the amount of ethanol added to the tobacco raw material.

The ethanol-impregnated tobacco raw material is then transferred to the carbon dioxide gas impregnation step. At that time, the ethanol-impregnated tobacco raw material is charged in a pressure vessel having an outer jacket. When impregnating carbon dioxide gas, a heat exchange medium is circulated in the jacket of the pressure vessel, and pressure and temperature conditions sufficient to maintain carbon dioxide in a gaseous state (when the ethanol impregnation concentration is low, preferably gas The desired impregnation can be achieved by supplying carbon dioxide gas to the pressure vessel under a temperature condition where the pressure can be maintained at or near the saturation point) and placing the ethanol-impregnated tobacco raw material for 15 seconds to 30 minutes under the above conditions. The temperature for impregnating carbon dioxide gas is usually -55 ° C to 50 ° C, preferably -25.
Temperatures between 0 ° C and 50 ° C can be used. Carbon dioxide gas is preferably impregnated in the tobacco raw material at a ratio of 1% by weight or more.

When the impregnation with carbon dioxide gas is complete, release the pressure,
Take out the tobacco raw material impregnated with ethanol-carbon dioxide gas. The pressure can be released in 1 second to 10 minutes by exhausting the valve operation which is usually performed, though it depends on the volume and pressure of the pressure vessel.

The extracted ethanol-carbon dioxide gas-impregnated tobacco raw material is subjected to a heat treatment to remove ethanol and carbon dioxide gas, and the tobacco raw material is expanded. The transition to the expansion step is preferably performed within a short time so that ethanol and carbon dioxide gas are not scattered as much as possible from the tobacco raw material. The puffing heat treatment of the tobacco raw material is carried out by heating the tobacco raw material impregnated with ethanol-carbon dioxide gas into a stream of air, steam or a mixture thereof heated to a temperature of usually 100 ° C. or higher, preferably 125 ° C. to 225 ° C. This can be most conveniently carried out by exposing the tobacco material to a time sufficient for the tobacco material to swell by removal of (gas stream drying). This swelling heat treatment can usually be accomplished in 1 to 30 seconds.

When the tobacco raw material is first impregnated with ethanol as described above, the pressure during carbon dioxide gas impregnation is 15 to 30 kg / cm ^2.
It is low and the swelling rate is sufficiently high even under the condition that the temperature of the airflow during the swelling heat treatment is 200 ° C. or lower, which is a temperature at which the flavor and taste of the tobacco raw material is not affected, that is, the swelling cannot be sufficiently swelled by only carbon dioxide gas impregnation ( (To be defined hereinafter) can be achieved, and the flavor and taste of the tobacco raw material is not adversely affected. In addition, the ethanol and carbon dioxide gas used do not have any adverse effect on the flavor and taste of the tobacco raw material. From the viewpoint of the expansion rate alone, it is effective to use a higher heat treatment temperature (for example, a temperature up to 350 ° C.), but as described above, if the temperature is too high, the treatment time is short. A smoky odor is produced, which adversely affects the flavor and taste of the tobacco raw material. The carbon dioxide impregnation pressure is 30 kg /
Even if it is cm ² or more, it also shows a high swelling rate. further,
Other lower aliphatic alcohols, acetone acetic acid, benzene and carbon tetrachloride can be used in place of ethanol, but these substances are not used here because they adversely affect the flavor and taste of the tobacco raw material.

Here, the expansion rate is defined as the quotient (ρ ₀ / ρ) obtained by dividing the apparent density (ρ ₀ ) of the tobacco raw material to be expanded by the apparent density (ρ) of the tobacco raw material after expansion. According to the present invention, ethanol cannot be obtained alone or carbon dioxide gas alone cannot be obtained even under the above-mentioned low pressure and low temperature conditions.
A swelling rate of 0 or more can be achieved.

〔Example〕

Example 1 With a water content of 14%, mercury porosimetry (measurement pressure 250 kg / cm ² a
9.5 g of ethanol was added to 300 g of yellow-cut tobacco material having an apparent density ρ ₀ of 0.887 g / cm ³ measured in bs).
It was sprayed with 30% by weight or 30% by weight and stored for 30 minutes. The ethanol-impregnated tobacco raw material was charged into a pressure vessel having an internal volume of 4 liters, which was maintained at about 0 ° C. by circulating a heat exchange medium in the outer jacket, and carbon dioxide gas was introduced into the pressure vessel.
Pressurized to kg / cm ² . Under this condition, carbon dioxide gas was impregnated for 10 minutes. Then, the pressure was released. The pressure release time was about 30 seconds. Remove the ethanol-carbon dioxide gas impregnated tobacco raw material from the pressure vessel,
Immediately, 20m of heated air at the temperature shown in Table 1 below
It was swelled by putting it in an air flow dryer flowing at a flow rate of / sec and taking it out for 5 seconds.

The respective tobacco raw materials thus obtained were stored for 1 week in a constant temperature and constant humidity chamber at 22 ° C. and a relative humidity of 60% for harmonization. The apparent density ρ of these expanded cigarettes was measured by the mercury intrusion method, and the expansion rate (ρ ₀ / ρ) was calculated.

In addition, each of the harmonized tobacco raw materials was rolled up, cigarettes were wrapped, and the flavor and taste was evaluated by a specially trained expert panel of 10 people. In this sensory test, neither ethanol nor carbon dioxide gas was impregnated, heated and expanded at a temperature of 150 ° C., and then rolled up in harmony with a relative humidity of 60%,
A cigarette was used as a control. The flavor and aroma are the same as the control product, 0, slightly superior, +1, considerably superior, +2, extremely superior, +
3 is evaluated as being slightly inferior, -1 is considerably inferior, and -2 is extremely inferior.

In addition, a puffed tobacco raw material obtained by the completely same treatment except that the ethanol impregnation treatment was not carried out was similarly tested.

The above results are also shown in Table 1.

As is clear from the results of Table 1, the ethanol-carbon dioxide gas-impregnated tobacco raw material exhibits an excellent expansion rate at any heating and expansion temperature as compared with the carbon dioxide gas-impregnated tobacco raw material. The tobacco raw material impregnated only with carbon dioxide gas does not show a high expansion rate under the conditions shown in Table 1, but under the heating expansion temperature conditions showing a relatively high expansion rate, a fragrant taste and a dark odor are developed. On the other hand, the tobacco raw material impregnated with ethanol-carbon dioxide gas exhibited a high expansion rate even at a relatively low heating expansion temperature, and did not exhibit a burning odor. Also, the heating and swelling temperature of 200 ° C. to 2
At 25 ° C., a burning odor was exhibited in the tobacco raw material impregnated with carbon dioxide gas only, whereas no burning odor was observed in the ethanol raw material impregnated with carbon dioxide. It is considered that this is because the product temperature can be lowered by the latent heat of vaporization of ethanol as compared with a cigarette impregnated with only carbon dioxide gas.

Example 2. The same tobacco raw material as that used in Example 1 was charged into a pressure vessel, and carbon dioxide gas impregnation was performed for 10 minutes under the pressure and temperature conditions shown in Table 2 below. Thereafter, the pressure was released, the tobacco raw material was taken out of the pressure vessel, immediately put in an air flow dryer in which heated air at 150 ° C. at a flow rate of 20 m / sec, and taken out for 5 seconds. The expansion rate of each expanded tobacco raw material thus obtained was calculated in the same manner as in Example 1. The results are also shown in Table 2.

As is clear from Table 2, the cigarettes impregnated with ethanol-carbon dioxide gas showed excellent expansion rates under all impregnation conditions as compared with the cigarettes impregnated with carbon dioxide gas only. Further, the swelling rate was sufficiently satisfactory even under a low pressure condition of the impregnation pressure of 30 kg / cm ² or less.

Example 3 The yellow seed tobacco raw material used in Example 1 was sprayed with ethanol and stored for 10 minutes to obtain a tobacco raw material having ethanol impregnated amounts of the various seeds shown in Table 3 below. Each ethanol-impregnated tobacco raw material was immediately charged into a pressure vessel and impregnated with carbon dioxide gas under the impregnation conditions shown in Table 3. Then, the pressure was released, and the ethanol-carbon dioxide gas-impregnated tobacco raw material was taken out from the pressure vessel, and immediately put into a gas stream dryer in which heated air at 150 ° C flows at a flow rate of 20 m / sec.
It was swelled by taking it out for 5 seconds. The expansion rate of each expanded tobacco raw material thus obtained was calculated in the same manner as in Example 1. The results are also shown in Table 3.

As is clear from the results in Table 3, the ethanol-carbon dioxide gas-impregnated tobacco raw material exhibited an excellent expansion rate at any ethanol impregnation amount as compared with the carbon dioxide gas-impregnated tobacco raw material.

Example 4 The same yellow seed tobacco material as that used in Example 1 was impregnated with ethanol and carbon dioxide gas and heated and expanded under the conditions shown in Table 4 below. Table 4 also shows the expansion rates of the obtained expanded tobacco raw materials.

As is clear from the results shown in Table 4, the tobacco raw material impregnated with ethanol exhibits an excellent expansion rate at a carbon dioxide gas impregnation time of 5 minutes or more, whereas the tobacco raw material not impregnated with ethanol is sufficient. It takes a long time to impregnate carbon dioxide gas in order to achieve a high expansion rate.

Example 5 Using a Burley type tobacco raw material, ethanol impregnation and carbon dioxide gas impregnation and heat expansion were performed under the conditions shown in Table 5 below. The expansion rate of each expanded cigarette is also shown in Table 5.

As is clear from the results in Table 5, the method of the present invention has excellent effects on Burley seeds.

Example 6 Using air or carbon dioxide gas as the impregnating gas, expansion treatment was performed under the conditions shown in Table 6 below. The results are also shown in Table 6.

As is clear from the results of Table 6, an excellent expansion rate can be achieved only by first impregnating with ethanol and then impregnating carbon dioxide gas.

Example 7 Tobacco raw materials similar to those used in Example 1 were impregnated with ethanol (EtOH) at various concentrations shown in Table 7, and 25 kg / cm
Carbon dioxide was impregnated under the pressure of ² at the temperature shown in Table 7 for 10 minutes. Table 7 also shows the expansion rate of each expanded cigarette.

As is clear from the results shown in Table 7, the closer the carbon dioxide impregnation temperature is to the saturation point, the better the swelling rate, but as the ethanol impregnation concentration increases, the carbon dioxide gas impregnation temperature increases even if the carbon dioxide impregnation temperature increases. It shows the same swelling rate as the gas impregnation temperature is close to the saturation point. This is because the carbon dioxide gas has a high solubility in ethanol. If the ethanol impregnation concentration is 30% or more, the swelling rate is almost the same at a temperature of 20 ° C. or less, and the ethanol impregnation concentration is 15 to 2
At 0%, almost the same swelling tendency is exhibited.

〔The invention's effect〕

As described above, according to the method for expanding a tobacco raw material of the present invention, even under relatively low carbon dioxide gas impregnation pressure, relatively short carbon dioxide gas impregnation time and / or relatively low heat expansion and temperature conditions. A sufficiently high puffing rate can be obtained, and thus the tobacco raw material can be puffed without adversely affecting the flavor and taste of the cigarette.

Claims (1)

[Claims] 1. A tobacco raw material to be expanded is impregnated with ethanol, the ethanol-impregnated tobacco raw material is charged into a pressure vessel, and carbon dioxide gas is introduced into the pressure vessel to apply the carbon dioxide gas under pressure to the ethanol. The tobacco raw material is impregnated with the impregnated tobacco raw material, and then the pressure of the pressure vessel is released, and the obtained ethanol-carbon dioxide gas impregnated tobacco raw material is subjected to heat treatment to remove ethanol and carbon dioxide gas from the tobacco raw material to obtain a tobacco raw material. A method for expanding a tobacco raw material, which comprises expanding.