PROCESS FOR MANUFACTURING WRINKLED SHEET TOBACCO

Abstract: A process for manufacturing wrinkled sheet by wetting tobacco-containing raw powder with water, extruding the powder through a pair of pressure rollers, and separating the sheet tobacco adhered and formed on the surface of one of the pressure roller using a doctor knife, which comprises adding one of the following substances in an amount shown below to the raw powder: (1) α-starch or propylene glycol: 4 to 10 wt %; (2) hydrolyzed starch with a molecular weight of 100,000 to 900,000, gum arabic, carboxymethylcellulose salt with a molecular weight of 10,000 to 20,000 or high-methoxy pectin with a degree of methoxylation of 7 to 17 % and a de­ gree of esterification of 62 to 77 %: 4 to 11 wt %; and (3) a mixture of 4,4,6-triglucosaccharide polymer (1.9 to 7.9 wt %) and carboxymethylcellulose sodium salt (1.3 to 3.2 wt %).

Description: [Technical Field] The present invention relates to a method of manufacturing wrinkled sheet tobacco by wetting a raw material, powder containing tobacco with water, extruding the resultant wet powder through a gap between a pair of rollers, and separating sheet tobacco attached to the surface of one roller with a doctor knife, wherein a binder is added to the raw material powder. [Background Art] So-called cut tobacco obtained by cutting tobacco leaves is used for usual tobacco articles such as cigarettes. In the step of cutting tobacco leaves or in other tobacco manufacturing steps, various types of tobacco waste such as leaf waste, cut waste, powder tobacco, or rib waste are produced. Conventionally, in order to effectively utilize such tobacco waste, it is bound with a suitable binder, and added with a reinforcing agent, a humectant, and the like. The mixture is extruded through a gap between a pair of rollers to form a sheet, and the sheet attached to the surface of one roller is separated therefrom with a doctor knife to obtain sheet tobacco (see Japanese Patent Publication No. 48-5919). The sheet tobacco is cut and mixed with normal cut tobacco and used as a raw material for cigarettes and the like. When sheet tobacco manufactured in the above manner has wrinkles, it has considerable filling capacity (i. e. is bulky) when cut. Therefore, the amount of cut tobacco rolled as cigarettes can be reduced, resulting in economical advantages. In the above-mentioned method, when the sheet is separated by the doctor knife, wrinkles are formed in the sheet. However, as shown in Fig. 1 , wrinkles formed in sheet tobacco in this manner are small wrinkles having a pitch of 0.1 to 0.2 mm and a height including the sheet thickness of about 0.2 mm when sheet tobacco having a thickness of 0.1 mm is used. Therefore, this sheet does not provide sufficient filling capacity when cut. Japanese Patent Publication No. 48-4919, mentioned above, discloses the use of a special doctor knife for forming large wrinkles. However, large wrinkles can be formed for only a short period of time due to wear on the doctor knife. US-A-3 430 634 discloses a process for making a tobacco product for using a smokable article. The process involves formation of an aqueous slurry, wherein a wet mixture containing tobacco and a binder is extruded through a gap between a pair of rollers and sheet tobacco attached to the surface of one roller is separated with a doctor knife. Although the use of a binder is mentioned no specific examples are recited. Moreover, the said document does not even remotely suggest that the use of a binder is involved in the formation of wrinkles in a sheet tobacco. US-A-2 887 414 discloses a method of making tobacco smoking material by using specific adhesives. The use of any particular binder for the formation of wrinkles in a sheet tobacco is neither disclosed nor suggested. Likewise, BE-A-525 814 does not disclose or suggest that the use of a binder is involved in the formation of wrinkles in a sheet tobacco, although the use of pectin or a derivative thereof is being mentioned in general, i. e. a material which may be used as a binder if available in a specific form in the formation of wrinkles. However, - as mentioned above - with respect to this matter BE-A-525 814 is completely silent. [Disclosure of Invention] It is an object of the present invention to provide a method of manufacturing wrinkled sheet tobacco which results in an improved water resistance and filling capacity of the tobacco. The above object is achieved by using a specified amount of a specified substance as a binder. Thus, there is provided according to the present invention a method of manufacturing wrinkled sheet tobacco by wetting a raw material powder containing tobacco with water, extruding the resultant wet powder through a gap between a pair of rollers, and separating sheet tobacco attached to the surface of one roller with a doctor knife, wherein one of the substances selected from those enumerated below is added to the raw material powder in an amount defined below. The amount defined below is an amount based on the overall weight of the powder before wetting with water (i. e., the total weight of the raw material powder): (1) 4 to 10% by weight of an α-starch or propylene glycol alginate ester; (2) 4 to 11% by weight of a hydrolyzed starch having a molecular weight of 100,000 to 900.000, gum arabic, a carboxymethyl cellulose salt having a molecular weight of 10,000 to 20,000, or a high methoxyl pectin having a degree of methoxylation of 7 to 17% and a degree of esterification of 62 to 77%; and (3) a mixture of 1.9 to 7.9% by weight of a 4.4.5-triglucosaccharide polymer and 1.3 to 3.2% by weight of sodium carboxymethyl cellulose. When a predetermined amount of one of the substances enumerated above is added as a binder to the raw material powder, sheet tobacco having large wrinkles with a pitch of about 2 mm and a height of about 1 mm can be obtained. Wrinkles formed by the method of the present invention are different from those formed by conventional methods in that small wrinkles are present in large wrinkles to provide a greater filling capacity, as shown in Fig. 2. In addition, the method of the present invention does not require a special doctor knife, as in Japanese Patent Publication No. 48-5919, and allows formation of large wrinkles even upon considerable wear of the doctor knife. Sheet tobacco prepared by the method of the present invention has excellent water resistance, and provides good taste when smoked, as will be described with reference to Examples to be described later. [Brief Description of Drawings] Fig. 1 is a sectional view schematically showing the size and shape of sheet tobacco obtained by a conventional method: Fig. 2 is a sectional view schematically showing the size and shape of sheet tobacco obtained by the method of the present invention: and Fig. 3 is a schematic diagram for explaining the method of the present invention. [Best Mode of Carrying Out the Invention] According to the method of the present invention, a raw material powder containing tobacco, such as tobacco waste, is prepared and is wetted with water. Like a conventional raw material powder, the raw material powder used in the present invention contains tobacco, such as tobacco waste or rib waste, a binder, and optionally additives such as a humectant, a reinforcing agent, and a water resistance agent. Water is added thereto in order to wet the raw material (i.e. , to provide a suitable water content). The most important characteristic of the present invention is that a specified amount of the specified substance is used as the binder. The following substances can be used as the binder herein: (1) α-starch; (2) propylene glycol alginate ester: (3) hydrolyzed starch having a molecular weight of 100,000 to 900,000; (4) gum arabic; (5) a salt of a carboxymethyl cellulose having a molecular weight of 10,000 to 20,000 (a sodium salt, a potassium salt, or the like); (6) high methoxyl pectin having a degree of methoxylation of 7 to 17% and a degree of esterification of 62 to 77%; and (7) a mixture of a 4,4,6-triglucosaccharide polymer (pullulan) and sodium carboxymethyl cellulose A binder selected from those enumerated above must be used in a specified amount. More specifically, when substance (1) or (2) above is used, it must be used in an amount of 4 to 10% by weight based on the total weight of the raw material powder (i.e. , the total weight of the powder before addition of water). When anyone of substances (3) to (6) is used, it must be used in an amount of 4 to 11% by weight based on the above-mentioned total weight. When substance (7) is used, it must be used such that 4,4,6-triglucosaccharide polymer is 1.9 to 7.9% by weight, and sodium carboxymethyl cellulose is 1.3 to 3.2% by weight. Other components of the raw material powder according to the present invention are the same as those used in conventional one. More specifically, tobacco can be selected from various tobacco wastes, including leaf waste, cut waste, tobacco powder, rib waste, and winnower waste. The raw material powder contains tobacco in an amount of 50 to 98%, and preferably 70 to 95%. As in conventional methods, the raw material powder can also contain suitable amounts of a humectant, a reinforcing agent, a water resistance agent, and the like. The humectant can, for example, be a mixture of propylene glycol and corn syrup (in a weight ratio of, e.g., 1 : 2). The reinforcing agent can be, e.g., fibrillated pulp. The water resistance agent can be, e.g., glyoxal or the like. The wet raw material powder is prepared by mixing these respective components to provide a raw material powder and then adding water to the powder to obtain a suitable water content of the wet raw material powder. The wet raw material powder has a water content of 30 to 70%, and preferably 40 to 60%. As shown in Fig. 3, wet raw material powder 2 thus prepared is extruded as a sheet from a gap between a pair of rollers 1, which rotate in opposite directions. Preferably,, the peripheral speed of the rollers is 20 m/min or more, and, more preferably, 70 m/min or more. The gap between rollers 1 is normally selected to be about 0.1 mm. When the wet powder is extruded through the gap between rollers 1, resultant sheet 3 is attached to the surface of one roller. Sheet 3 is then removed from roller 1 with doctor knife 4. Separated sheet 5 is then placed on belt conveyor 7 and is conveyed to the next processing area. According to the method of the present invention, separated sheet 5 has large wrinkles, as shown in Fig. 2. In addition, small wrinkles are formed in the large wrinkles to increase the filling capacity. The wrinkled sheet tobacco manufactured by the method of the present invention has a filling capacity of 35 to 42 cm³ when tested by a filling capacity test described in Test Example 1 below. when a water resistance test, also described in Test Example 1, is performed, the sheet tobacco of the present invention has a shape retention property for 30 minutes or longer. The wrinkled sheet tobacco prepared in this manner is cut and mixed with raw materials for, e.g., cigarettes. Test Example 1 The components shown in Tables 1 and 2 were mixed in the mixing ratios shown in the Tables. Water was added to each mixture to provide a wet raw material powder having a water content of 30%. Each wet powder was supplied to a gap between a pair of rollers rotating in opposite directions at a peripheral speed of 75 m/min. Each sheet tobacco attached to one roller was separated therefrom with a doctor knife, was placed on a belt conveyor, and was fed into a drier. Sheet tobaccos having a water content of 11% by weight and a thickness of 0.1 mm were thus prepared. The sheets were cut into widths of 0.8 mm and lengths of 10 mm to provide cut tobaccos. Using the respective cut tobacco, obtained in this manner, an increase in filling capacity, with reference to that of Control cut tobacco, was measured. Filling capacity was measured according to the following procedures. Fifteen grams of each cut tobacco were charged into a cylindrical container having an inner diameter of 72 mm and were compressed at a constant speed of 0.5 mm/sec, and the capacity of the tobacco was measured when a stress reaches 250 g/cm. The capacity of the Control cut tobacco was also measured under the same conditions. The percentage of the capacity of each tobacco of the present invention with respect to that of the Control cut tobacco was calculated. The capacity of the Control cut tobacco was 33 cm³. The increase in water resistance of the sheet tobaccos obtained in the above manner was measured according to the following procedures. One hundred and fifty milliliters of warm water at 30°C were poured into a petri dishes having a diameter of 20 mm. The sheet tobaccos were cut into a circular form having a diameter of 30 mm and were placed in the respective petri dishes. The petri dishes were shaken horizontally six times per minute at an amplitude of 16 mm five seconds for intervals of 5 seconds. The time required for tearing the circular sheet taboccos into three or more pieces was measured, and is expressed in % with reference to the Control sheet tobacco. The Control sheet tobacco had a water resistance (time) of 10 minutes. The powder as a raw material for the control sheet tobacco and the control cut tobacco had the following composition: 54% of raw material waste tobacco, 35% of winnower waste, 3% of sodium carboxymethyl cellulose, 2% of glyoxal, 3% of propylene glycol, 3% of sorbitol, and water in an amount to provide a water content of 60%. As can be seen from the results shown in Tabel 1, when one of the starches is used as the binder in an amount of 4 to 10% by weight, many wrinkles like those shown in Fig. 2 can be formed, and the filling capacity increases by 5 to 23% over that of conventional sheet tobacco, although each different starch has a slightly different filling capacity-increasing degree. Water resistance is also increased by 80 to 210%. In contrast to this, when dialdehyde starch, etherified starch, or phosphate starch is used as the binder, no wrinkles are formed, filling capacity is lower than that of conventional sheet tobacco, and no increase in water resistance is observed. As can be seen from the results shown in Table 2, when a hydrolyzed starch having a molecular weight of 100,000 to 900,000 is used in an amount of 4 to 11% by weight as the binder, many wrinkles like those shown in Fig. 2 are formed. The filling capacity increases by 9 to 13% and the water resistance increases by 10 to 33% over those of conventional sheet tobacco. When a hydrolyzed starch having a molecular weight of 10,000 to 90,000, i.e., a higher degree of hydrolysis, is used, the filling capacity and water resistance are poorer than those of conventional sheet tobacco. When a hydrolyzed starch having a molecular weight of 1,000,000 to 9,000,000, i.e., a lower degree of hydrolysis, is used, no wrinkles are formed and filling capacity is still poorer. Test Example 2 Six panelists smoked cut tobaccos of Example 2, Example 6, Example 10 and Example 14, and the Control cut tobacco, and evaluated the aroma, taste, peculiarity in taste, and stimulation in accordance with a ±3 point method. The evaluation standards were as follows: +3: much better than Control +2: significantly better than Control +1: slightly better than Control 0: equivalent to Control -1: slightly poorer than Control -2: significantly poorer than control -3: much poorer than control The obtained results are shown in Table 3 below. Values in the Table are average values of the six panelists. It is seen from Table 3 that the tobaccos manufactured by the method of the present invention have qualities, such as aroma, taste, peculiarity in taste, or stimulation, that are equivalent to or better than those of conventional tobacco. Test Example 3 The components shown in Table 4 were mixed in the mixing ratios shown in the Table. Water was added to the mixtures to provide wet raw material powders having a water content of 30%. Each wet powder was treated following the same procedures as in Test Example 1, and the filling capacity increase in the resultant sheet tobacco was measured. The obtained results are shown in Table 4. As is apparent from the results shown in Table 4, when propylene glycol alginate ester is used in an amount of 4 to 10% by weight as the binder, many wrinkles like those shown in Fig. 2 are formed, and the filling capacity increases by 9 to 15% over conventional wrinkled sheet tobacco. In contrast to this, when sodium alginate or potassium alginate is used, no wrinkles are formed and the filling capacity is poorer than that of conventional wrinkled sheet tobacco. The different results obtained in accordance with the different types of binder are assumed to be attributed to the physiochemical properties of the binders, such as flowability, adherence, or contraction. Test Example 4 The components shown in Table 5 were mixed in the mixing ratios shown in the Table. Water was added to the mixtures to provide wet raw material powders having a water content of 30%. Each wet powder was treated following the same procedures as in Test Example 1, and the filling capacity increase in the resultant sheet tobacco was measured. The obtained results are shown in Table 5. As can be seen from the results shown in Table 5, when a carboxymethyl cellulose salt having a molecular weight of 10,000 to 20,000 is used in an amount of 4 to 11% by weight as the binder, many wrinkles like those shown in Fig. 2 are formed, and the filling capacity increases by 6 to 9% over conventional wrinkled sheet tobacco. In contrast to this, when a carboxymethyl cellulose salt having a molecular weight of 22,000 to 30,000 is used, no substantial effect is obtained. When a carboxymethyl cellulose salt having a molecular weight. of 40,000 to 50,000 or 100,000 to 150,000 (conventional) is used, no wrinkles are formed and the filling capacity is poorer than conventional wrinkled sheet tobacco. Test Example 5 The components shown in Table 6 were mixed in the mixing ratios shown in the Table. Water was added to the mixtures to provide wet raw material powders having a water content of 30%. Each wet powder was treated following the same procedures as in Test Example 1, and the filling capacity increase in the resultant sheet tobacco was measured. The obtained results are shown in Table 6. As can he seen from the results in Table 6, when gum arabic is used in an amount of 4 to 11% by weight as the binder, many wrinkles like those shown in Fig. 2 are formed, and the filling capacity increases by 8 to 16% over conventional wrinkled sheet tobacco. In contrast to this, when a natural gum, either locust bean gum or guar gum, is used, no wrinkles are formed and the filling capacity is poorer than conventional wrinkled sheet tobacco. Test Example 6 The components shown in Table 7 were mixed in the mixing ratios shown in the Table. Water was added to the mixtures to provide wet raw material powders having a water content of 30%. Each wet powder was treated following the same procedures as in Test Example 1, and the filling capacity increase in the resultant sheet tobacco was measured. The obtained results are shown in Table 7. As can be seen from Table 7, when a high methoxyl pectin having a degree of methoxylation of 7 to 17% and a degree of esterification of 62 to 77% is used as the binder, many wrinkles like those shown in Fig. 2 are formed, and the filling capacity increases by 12 to 20% over conventional sheet tobacco, although each different high methoxyl pectin has a slightly different filling capacity-increasing degree. In contrast to this, when a low methoxyl pectin having a degree of methoxylation below 17% or a high methoxyl pectin having an esterification degree lower limit below 62% is used, no wrinkles are formed and the filling capacity is poorer than conventional wrinkled sheet tobacco. Test Example 7 The components shown in Table 8 were mixed in the mixing ratios shown in the Table. Water was added to the mixtures to provide wet raw material powders having a water content of 30%. Each wet powder was treated following the same procedures as in Test Example 1, and the filling capacity increase in the resultant sheet tobacco was measured. The obtained results are shown in Table 8. As can be seen from the results shown in Table 8, when a 4,4,6-triglucosaccharide polymer is used in an amount of 3.2 to 9.2% by weight as the binder, wrinkles are formed, but water resistance is poorer though the filling capacity increases by 4 to 11% over conventional wrinkled sheet tobacco. In contrast to this, when a mixture of 1.9 to 7.9% of a 4,4,6-triglucosaccharide polymer and 1.3 to 3.2% of sodium carboxymethyl cellulose is used as the binder, many wrinkles are formed, the sheet strength is increased, and the filling capacity and water resistance increase by 10 to 22% and 12 to 67%, respectively, over conventional wrinkled sheet tobacco.

Claims: A method of manufacturing wrinkled sheet tobacco by wetting a raw material powder containing tobacco with water, extruding the resultant wet powder through a gap between a pair of rollers, and separating sheet tobacco attached to the surface of one roller with a doctor knife, wherein one of the following substances is added to the raw material powder as a binder: (1) 4 to 10% by weight of an α-starch; (2) 4 to 10% by weight of propylene glycol alginate ester; (3) 4 to 11% by weight of a hydrolyzed starch having a molecular weight of 100,000 to 900,000; (4) 4 to 11% by weight of gum arabic; (5) 4 to 11% by weight of a carboxymethyl cellulose salt having a molecular weight of 10,000 to 20,000; (6) 4 to 11% by weight of a high methoxyl pectin having a degree of methoxylation of 7 to 17% and a degree of esterification of 62 to 77%; (7) a mixture of 1.9 to 7.9% by weight of a 4,4,6-triglucosaccharide polymer and 1.3 to 3.2% by weight of sodium carboxymethyl cellulose, wherein all the aforementioned weight percentages are based on the weight of the raw material powder. A method according to claim 1, wherein a rotating speed of the rollers, in terms of a peripheral speed, is not less than 20 m/min.

Inventors: FURUYA, NORIO 6-34, KUROBEOKA, KATAOKA, SATORU 6-34, KUROBEOKA, OHASHI, YUKINARI 6-34, KUROBEOKA, WATANABE, MASATAKA 14-38, TSUNASHIMA NISHI 5-CHOME
Applicants: JAPAN TOBACCO INC.
Application year: 1985
Main classification: A24B3
IPC codes: A24B3