MXPA00004982A - A method for making a reconstituted tobacco sheet using steam exploded tobacco - Google Patents

Abstract

A process for improving smoke quality and mechanical properties of a cast reconstituted tobacco sheet is accomplished by adding tobacco materials to an aqueous solution containing ammonium salts and ammonium hydroxide. The resulting first tobacco slurry is then pressurized under steam pressure to at least 60 psi for a period of from about 1 to 5 minutes then depressurized rapidly to ambient. The depressurized tobacco is then formed into a second tobacco slurry. The resulting tobacco residue is then cast into a reconstituted tobacco sheet for further processing into smoking articles.

Description

A METHOD FOR MAKING A RECONSTITUTED TOBACCO LEAF USING STEAM EXPANDED TOBACCO TECHNICAL FIELD This invention relates to a tobacco treatment process with high pressure and temperature and more particularly to a process to improve the smoking quality and the mechanical properties of a tobacco sheet reconstituted by steam expanded tobacco. BACKGROUND OF THE INVENTION In the manufacture of smoking articles, such as cigarettes, pipe tobacco and the like, a substantial portion of the tobacco that has been processed for use in smoking articles was found to be unsuitable for use because of its proprietary properties. undesirable size or taste. For example, the stems and fines of the tobacco manufacturing processes are unsuitable for use in the manufacture of these smoking articles. Since stems and fines represent a substantial amount of investment in raw material, processes have been developed to further process these stems and fines in products such as reconstituted tobacco leaves, which can be used in relatively large quantities in a mixture with leaves. of processed tobacco acceptable. In the processing of reconstituted tobacco some of the components within the stems and fines are solubilized and separated from the tobacco solids. These solubilized components are either discarded or a portion thereof or re-introduced at a later stage of processing reconstituted tobacco leaves. For example, U.S. Pat. No. 4,744,375 issued to Denier et al. Teaches the process for using compounds imparting tobacco flavor, such as ammonia, to make a tobacco product which can be used in reconstituted tobacco leaves. SUMMARY OF THE INVENTION The present invention relates to a method for providing a reconstituted tobacco material, wherein the tobacco in the form of stems and fines is dispersed in water. The resulting tobacco slurry or paste is heated inside a closed vessel under pressure with saturated steam and maintained for sufficient time to allow swelling or explosion of the tobacco. The container is rapidly depressurized to the environment, resulting in fiber formation of the tobacco particles and chemical depolymerization of some of the constituents within the tobacco. This mechanical action also causes a release and solubilization of pectins, and a slight morphological and structural transformation of the tobacco compounds. Ammonium hydroxide and an ammonium salt are added to the tobacco paste either before or after steam pressurization by preferably adding ammonium hydroxide and ammonium salt before steam pressurization. In the present invention, inverted sugars and active humectants as well as other selected chemical additives have also been found useful. It is therefore an object of the present invention to provide a tobacco product for use in reconstituted tobacco, resulting in less irritation, better tobacco flavor and better smoking quality. More particularly, the present invention is directed to a method for making a molded reconstituted tobacco sheet, comprising the steps of: adding from 50 to 100 parts by weight of tobacco materials to a container containing from 100 to 200 parts by weight of water, from about 2 to 20 parts by weight of ammonium salt, from about 3 to 25 parts by weight of ammonium hydroxide and less than one part by weight of humectant; bringing the first tobacco paste mixture from about 93 to 215.6 ° C (200 to 420 ° F) and 4.2 to 28.12 kg / cm2 (60 to 400 psi) with saturated steam for a period of from about 1 to 15 minutes; reduce the pressure of the first mixture of tobacco paste to the environment in a time from 0.1 to 1.0 minute; adding water to form a second tobacco paste having up to 90% by weight of water; reduce the size of tobacco particles; and forming a molded tobacco sheet product containing from about 9 to 23% by weight. Preferably, in the present invention the ammonium salt is selected from the group consisting of diammonium phosphate, ammonium acetate, ammonium chloride, ammonium phosphate and mixtures thereof. Humectants, such as glycerin and propylene glycol, as well as inverted sugars, such as glucose and fructose, may also be employed. The preferred temperature at which the first tobacco paste must be heated will be about 168 ° C (335 ° F) with about 7.03 kg / cm2 (100 psi) of saturated steam where the tobacco will be subjected to vapor pressure and temperature for a time of about 3 minutes. In an alternate embodiment, the chemical additives are added to the first tobacco paste after the first tobacco paste has been subjected to saturated steam from approximately 93 to 215.6 ° C (200 to 420 ° F) and 4.2 to 28.12 kg / cm2 (60 to 400 psi) for a period of about 1 to 15 minutes and then reduce the pressure to the environment, prior to the next processing in a molded sheet of tobacco. A better understanding in the present invention will be achieved from the following processes and the examples following said description.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic of a preferred process of the present invention; Figure 1A is a schematic of another process of the present invention; and Figure 2 is an elevation view of a preferred system for explosion with tobacco vapor of the present invention. DETAILED DESCRIPTION OF THE PREFERRED MODALITY In a preferred method for carrying out the portion of the vapor explosion of the present invention, as illustrated in Figure 2, tobacco materials in the form of fragments cured with combustion gases, fragments of thin-leaved and light-colored tobacco (burley), manufacturing and threshing powder, fragmented tobacco flour, stems cured with exhaust gases, thin-leaved and light-colored tobacco stems (burley), and the like, are introduced at the entrance 12 of a pressure vessel 16 containing water, an ammonium salt, and ammonium hydroxide. A humectant and an inverted sugar can also be added. The total amount of tobacco is in the range of about 50 to 100 parts by weight to about 100 to 200 parts by weight of water, from about 2 to 20 parts by weight of ammonium salt, from about 3 to 25 parts by weight of ammonium hydroxide and less than one part by weight of humectant and less than one part by weight of invert sugar. Preferably, the total chemical additives will be from 5 to 20 parts by weight, the ammonium salt will be from 5 to 10 parts by weight wherein the ammonium hydroxide will be from 10 to 15 parts by weight and the humectant will be less than one. part by weight. A valve 14 is provided by the inlet 12 to close the container 16 after loading and before steam pressurization. Ammonium salts which have been found useful in the present invention include diammonium phosphate, ammonium acetate, ammonium chloride, ammonium phosphate and the like and mixtures thereof. Preferably, the ammonium salts are from 1 to 5 parts by weight. Other additives that have been found useful in the present invention include potassium sorbate, citrus pectin, also as a citric or lactic acid. Usually these additives are from 1 to 10 parts by weight and preferably less than 5 parts by weight. The resulting tobacco / water mixture or the first tobacco paste is then vaporized through the steam inlet 20 where steam with from 4.2 to 28.12 kg / cm2 (60 to 400 psi) has been introduced until the temperature of tobacco paste is increased from about 15.6 to 204.4 ° C (60 to 400 ° F). The resulting temperature is then maintained for about 1 to 15 minutes. Preferably, the vapor will be at approximately 7.03 kg / cm2 (100 psi) and approximately 168 ° C (335 ° F) with a retention time of 3 minutes. The steam pressure treated tobacco is rapidly depressurized to the environment of approximately 0.1 to 1.0 minute. The discharge valve 22 is then opened and the first tobacco paste is transferred through the conduit 26 into a cyclone separator 28 where the steam has been discharged through the outlet 24 and the resulting product is discharged from the discharge bottom. 30 for further processing. As illustrated in Figure 1, the pulp of the steam explosion portion in the process including the cyclone separator 28 is transferred to a pulp tank where the water is added to produce a second tobacco paste that has up to 90% by weight of water. In an alternate embodiment, ammonium hydroxide, ammonium salt, and other chemicals can be added in a second tobacco paste. The resulting second tobacco paste is transferred to a sprayer or disintegrator such as a Rietz type mixer, where the size of the particles of the tobacco fibers is smaller in size. The paste is then transported to a conventional steam heated drum or to a box dryer where the water is removed and simultaneously the tobacco is formed into sheets of reconstituted tobacco containing from about 10 to 30 parts by weight of water per 100 parts per part. in weight of tobacco. The resulting sheet is then prepared for further processing into smoking quality tobacco. Alternatively, as illustrated in Figure 1A, the tobacco paste of the steam explosion stage is processed without further addition of water. This paste has a higher viscosity and rheology. And, this paste is generally molded from a pressurized box or extrusion die onto a drum dryer heated with steam to form reconstituted tobacco sheets with improved mechanical properties. EXAMPLES 1 TO 20 For a better understanding of the present invention, the following examples are incorporated herein to illustrate the present invention without intending to be unduly limited in that manner. EXAMPLE 1 A mixture of tobacco materials of 4.69 kg (10.34 lbs.) Including tobacco waste or fragments, manufacturing and threshing powder, fragmented tobacco flour, cured stems with exhaust gases, thin-leaved and light-colored tobacco stems (burley), dispersed in 9.08 kg (20 pounds) ) of water containing .587 kg (1,293 pounds) of ammonium hydroxide, .488 kg (0.986 pounds) of diammonium phosphate, .070 kg (0.155 pounds) of invert sugar, .007 kg (0.0146 pounds) of sorbate from potassium and .234 kg (0.516 pounds) of glycerin. The chemical-tobacco-water mixture is then loaded into a steam vessel where saturated steam is introduced at 7.03 kg kg / cm2 (100 psi) to bring the temperature inside the vessel to 168 ° C (335 ° F). The temperature of 168 ° C (335 ° F) was maintained for three minutes. After three minutes, the pressure vessel is depressurized to the environment in less than 1 minute and simultaneously transferred to a cyclone separator where the steam has been discharged and the tobacco product has been recovered. A sample of .708 kg (1.56 pounds) of tobacco subjected to steam pressure was added to a vessel containing 4.5 liters of water. This paste mixture was then heated to 93.3 ° C (200 ° F) and maintained at this temperature for 5 minutes. This mixture was then mounted in a Rietz mixer, a high shear disintegrator, where the mixture is a fine paste. The paste was then formed into a film from about .025 cm (.025") thick with a gardener's knife on a stainless steel plate and then transferred to a steam-heated box dryer.The resulting molded sheet material was incorporated in the cigarettes EXAMPLE 2 A reconstituted tobacco sheet was made in the same manner in Example 2 as in Example 1, except that the paste mixture was maintained at 93.3 ° C (200 ° F) for 90 minutes. The resulting molded reconstituted sheet material was then incorporated into cigarettes EXAMPLE 3 This example was carried out in the same manner and with the same amounts of materials that were used in Example 1, the only change is that the tobacco was subjected to a pressure of tobacco of 4.71 kg / cm2 (67 psi) and 148.9 ° C (300 ° F) and maintained at this pressure and temperature for six minutes.The resulting molded reconstituted tobacco sheet was incorporated into cigars EXAMPLE 4 The molded reconstituted tobacco sheet was made in the same manner as in Example 3, except that the pulp was maintained at 93.3 ° C (200 ° F) for 90 minutes. EXAMPLE 5 This example was carried out in the same manner and with the same amounts of materials as used in Example 1, except that the tobacco was steam treated at 29.7 kg / cm2 (422 psi) and 204.4 ° C (400 ° F) for five minutes. EXAMPLE 6 A molded reconstituted tobacco sheet was made in the same manner as in Example 5, except that the pulp was maintained at 93.3 ° C (200 ° F) for 90 minutes.

EXAMPLE 7 This example was carried out in the same manner and with the same amounts of materials as used in Example 1, except that the tobacco was steam treated at 134 psi and 176.7 ° C (350 psi). ° F) for 10 minutes. EXAMPLE 8 A molded reconstituted tobacco sheet was made in the same manner as in Example 7, except that the paste mixture was maintained at 93.3 ° C (200 ° F) for 90 minutes. EXAMPLE 9 This example was carried out in the same way with the same amounts of materials as used in Example 1, except that the tobacco was steam treated at 7.03 kg / cm2 (100 psi) and 168 ° C (335 ° F) for 3 minutes. The tobacco was also kept in contact with the additives for 5-6 hours before the steam treatment.

EXAMPLE 10 A reconstituted tobacco sheet was made in the same manner as in Example 9, except that the paste mixture was maintained at 93.3 ° C (200 ° F) for 90 minutes. EXAMPLE 11 A total of 4.69 kg (10.34 pounds) of tobacco material in the form of tobacco waste or fragments, waste or fragments of thin-leaved and light-colored tobacco (burley), manufacturing and threshing powder, fragmented tobacco flour, small stems cured with exhaust gases, small and large thin-leaved and light-colored tobacco stems (burley) , it is dispersed in 9.08 kg (20 pounds) of water. The tobacco-water mixture then loaded into a steam pressure vessel and treated with 7.03 kg / cm2 (100 psi) of saturated steam increasing a temperature of 168 ° C (335 ° F) and kept under these conditions for three minutes . Subsequently, .708 kg (1.56 pounds) of tobacco subjected to steam pressure are added to 4.5 liters of water containing .587 kg (1,293 pounds) of ammonium hydroxide, .488 kg (0.986 pounds) of diammonium phosphate,. 070 kg (0.155 pounds) of inverted sugars, .007 kg (0.0146 pounds) of potassium sorbate and .234 kg (0.516 pounds) of glycerin. The mixture was heated to 93.3 ° C (200 ° F) and maintained at that temperature for 5 minutes. The resulting paste mixture was prepared in a high shear mixer to a fine paste consistency. The paste was then formed into a film about .025 cm (.025") thick with a gardener's knife on a stainless steel plate.The molded film was then dried in a steam-heated box dryer. The resulting molded reconstituted tobacco was incorporated into cigarettes EXAMPLE 12 A reconstituted tobacco sheet was made in the same manner in Example 12 as in Example 11, except that the paste mixture was maintained at 93.3 ° C. (200 ° F) for 90 minutes. The resulting molded reconstituted sheet was then incorporated into cigarettes. EXAMPLE 13 This example was carried out in the same manner and with the same amounts of materials that were used in Example 11, the only change is that the tobacco was subjected to a tobacco pressure of 4.71 kg / cm2 (67 psi) and 148.89 ° C (300 ° F) and maintained at this pressure and temperature for six minutes. The resulting molded reconstituted tobacco sheet was incorporated into cigarettes. EXAMPLE 14 A molded reconstituted tobacco sheet was made in the same manner as in Example 13, except that the paste mixture was maintained at 93.3 ° C (200 ° F) for 90 minutes. EXAMPLE 15 This example was carried out in the same manner and with the same amounts of materials that were used in Example 11, except that the tobacco was steam treated at 29.7 kg / cm2 (422 psi) and 204.4 ° C (400 ° F) for five minutes. EXAMPLE 16 A molded reconstituted tobacco sheet was made in the same manner as in Example 15, except that the paste mixture was maintained at 93.3 ° C (200 ° F) for 90 minutes. EXAMPLE 17 This example was carried out in the same manner and with the same amounts of materials that were used in Example 11, except that the tobacco was steam treated at 9.42 kg / cm2 (134 psi) and 176.7 ° C (350 ° F) for 10 minutes. EXAMPLE 18 A molded reconstituted tobacco sheet was made in the same manner as in Example 17, except that the paste mixture was maintained at 93.3 ° C (200 ° F) for 90 minutes.

EXAMPLE 19 This example was carried out in the same manner and with the same amounts of materials that were used in Example 11, except that the tobacco was steam treated at 7.03 kg / cm2 (100 psi) and 168 ° C (335 ° F) for 3 minutes. The tobacco was also kept in contact with the additives for 5-6 hours before the steam treatment. EXAMPLE 20 A molded reconstituted tobacco sheet was made in the same manner as in Example 10, except that the paste mixture was maintained at 93.3 ° C (200 ° F) for 90 minutes. Cigarettes prepared with molded reconstituted tobacco of Examples 11-20 were found to have mild and pleasant taste but those made with reconstituted tobacco of Examples 1-10, which were prepared by adding ammonium hydroxide and ammonium salt, prior to pressurization of steam were found to have a milder and more pleasant flavor, than those cigarettes using reconstituted tobacco of Examples 11-20. The above detailed description and the Examples are given first for further understanding and unnecessary limitations will not be understood from there since they will be obvious modifications for those skilled in the art when reading the description and can be made without departing from the spirit of the invention and scope of the appended claims.

Claims (15)

1. CLAIMS 1. A method for producing a molded reconstituted tobacco sheet, characterized in that it comprises the steps of: a) adding from 50 to 100 parts by weight of tobacco materials to a container containing from 100 to 200 parts by weight of water , from about 5 to 80 parts by weight of chemical additives including from about 2 to 20 parts by weight of ammonium salt, from about 3 to 25 parts by weight of ammonium hydroxide and less than one part by weight of humectant, the mixture resulting is a first tobacco paste, b) bringing the first tobacco paste to a temperature from about 93 to 215.6 ° C (200 to 420 ° F) with 4.2 to 29.53 kg / cm2 (60 to 420 psi) of saturated steam and maintaining said temperature and pressure for a period of about 1 to 5 minutes; c) reduce the pressure of the first tobacco paste to the environment from 0.1 to 1.0 minute; d) adding water to the first tobacco paste to form a second tobacco paste, the dough has up to 90% by weight of water; e) reducing the particle size of the tobacco of the second tobacco paste; and f) removing water from the second tobacco paste and simultaneously forming a molded tobacco sheet containing from about 9 to 23% by weight of water.
2. 2. - A method according to claim 1, characterized in that the ammonium salt is selected from the group consisting of ammonium acetate, ammonium chloride, ammonium phosphate and mixtures thereof.
3. 3. - A method according to claim 1, characterized in that the humectant is selected from the group consisting of glycerin and propylene glycol.
4. 4. - A method according to claim 1, characterized in that it includes the addition of other chemical additives that are chosen from the group consisting of potassium sorbate, urea, citrus pectin, citric acid, lactic acid, and invert sugars and mixtures of the same.
5. 5. - A method according to claim 4, characterized in that inverted sugars include fructose and glucose.
6. 6. - A method according to claim 4, characterized in that the inverted sugars are up to 1 part by weight.
7. 7. - A method according to claim 1, characterized in that it includes the reduction of the particle size in step e) with a container with stirring means.
8. 8. - A method according to claim 1, characterized in that it includes the elimination of water with a drum dryer.
9. 9. - A method according to claim 1, characterized in that the chemical additives having from 5 to 20 parts by weight.
10. 10. A method according to claim 1, characterized in that the ammonium salt having from 5 to 10 parts by weight.
11. 11. A method according to claim 1, characterized in that the ammonium hydroxide is present from 10 to 15 parts by weight.
12. 12. - A method according to claim 1, characterized in that the humectant is present from 2 to 8 parts by weight.
13. 13. - A method according to claim 2, characterized in that the ammonium phosphate is diammonium phosphate.
14. 14. - A method according to claim 1, characterized in that it includes a humectant.
15. 15. - A method according to claim 14, characterized in that the humectant is less than 1 part by weight.