MXPA98000890A - Process for explosion with steam of tab stem - Google Patents

Abstract

The present invention relates to a process for exploiting tobacco stems to improve the quality of smoke, and more particularly to a process for exploiting tobacco cells with high pressure steam, followed by rapid depressurization and stopping, in order to reduce negative contributors to smoke quality and form favorable flavor compounds

Description

STEAM EXPLOSION PROCESS FOR TOBACCO STALK DESCRIPTION OF THE INVENTION This invention relates to a process for exploiting tobacco stems to improve smoke quality, and more particularly to a process for exploiting tobacco stem cells with saturated steam to high pressure, followed by rapid depressurization and arrest, in order to reduce negative contributors to smoke quality and form favorable taste compounds. It has been generally known for years that treating fibrous vegetable substances with pressurized steam will contribute to the decomposition of the fibers. In addition, steam treatment has been used in conjunction with chemical additives, usually some form of ammonia and alkaline materials, to also modify the properties of tobacco.

For example, a patent expired long ago, United States Patent No. 42,319 assigned to Jacob S. Storer (1984), teaches that treating the fibrous part of plants (such as cane, grasses, leaves, or stems of plants that have long fibers or woody fibers) with chemicals (such as potash, soda, ammonia, lime or salts) and by means of steam, dissolves undesirable compounds that can impart quality or taste of the material. U.S. Patent No. 2,032,437 assigned to Richter (1936) teaches a process in which fiber is released from wood or other cellulosic raw material by the chemical action of a digestion liquid, such as sulfite or liqueur. cooked acid sulfite, while under confinement. U.S. Patent No. 2,964,518 assigned to Snyder (1960) teaches a process in which wood materials are subjected to the action of ammonia and steam at pressures in the range of 600 to 1250 PSIG and temperatures of approximately 250 to 300. ° C for up to 90 minutes to separate the fibrous portions and ligneous portions of the material. It is also generally known in the tobacco processing art to use steam and chemicals as a means to form flavoring compounds in tobacco. U.S. Patent No. 4,607,646 assigned to Lilly, Jr. et al. (1986) teaches that reacting ammonia with non-burley tobacco containing natural sugars, in a controlled pressure system heated to temperatures of 80 to 150 ° C in order to impart the taste characteristics of burley-like smoke, still retains substantially all the volatile components of tobacco. Several other patents are known that relate to processes for treating tobacco to form flavoring compounds. U.S. Patent No. 4,677,994 assigned to Denier et al. (1987) teaches treating, drying and expanding tobacco by applying a source of ammonia to tobacco, then treating the tobacco with ammonia with steam for a preselected period, the result being improved taste quality and total value of the tobacco. U.S. Patent No. 4,744,375 assigned to Denier et al. (1988) teaches introducing moistened tobacco into a containment zone, introducing a source of ammonia, and heating the containment zone to bring the tobacco to a selected temperature to produce flavor compounds in the tobacco. U.S. Patent No. 4,825,884 assigned to Denier et al. (1989) teaches contacting tobacco with citrus pectin, invert sugar, or diammonium phosphate, or a combination thereof, introducing the moistened tobacco into a containment zone together with an ammonium source, and heating the containment zone to bring the tobacco to a selected temperature to produce flavor compounds in the tobacco. Additionally, it is known in the tobacco processing art to use steam for the expansion of tobacco stems at relatively high temperatures. GB-A-675292 teaches or suggests that the vapor can be used as a swelling agent and then describes that saturated steam at an absolute pressure of 265 psig and organic products at 715 psig, particularly those that contain starch or protein are affected mainly by heat. U.S. Patent No. 4,211,243 teaches stem treatment with superheated steam from 150 ° C to 300 ° C. In general, the past tobacco treatment technique has used various combinations of steam, ammonia or chemicals to treat tobacco materials in order to form flavoring compounds or to decompose lignin and cellulose into wood products to form by-products useful in the manufacture of tobacco. other goods. In the present invention, a simple, efficient and economical process for treating tobacco is provided. The present invention recognizes the benefits, efficiency, economy and utility of treating tobacco stems, both burley and curing in draft, in an atmosphere of high pressure saturated steam for a short period of time, then releasing the pressure rapidly, so that causes the cells of the fibers of the tobacco stem to explode. This produces a tobacco stem product that has improved smoke properties. Additionally, the steam explosion of tobacco stems can be supplemented by pretreating tobacco stems with chemicals, such as ammonia or other alkaline compounds, although such chemical treatment is not required to modify smoke qualities or produce flavor compounds from tobacco stems. . The steam explosion of the tobacco stems is a means to fragment biopolymers that can be negative contributors to the quality of the stems' smoke when burned. High pressure steam is used to penetrate the cell walls of plants, where at a high temperature, the steam reacts with and breaks up biopolymers contained in the cells. It is suspected that several of these biopolymers are negative contributors to smoke quality. It has been found that reducing these negative contributors improves the sensory properties of tobacco, such as more body, better taste and less irritation. In addition, some byproducts of stem fragmentation exploited by steam can improve the quality of the smoke. In addition, the addition of chemical additives to tobacco stems prior to the steam explosion can improve the steam explosion process. Chemical additives include organic acids to catalyze hydrolysis, ammonia to react with sugars, and potassium carbonate to catalyze the production of flavor compounds from lignin. This invention provides a process that is especially useful since the principal reactant, water, in the formation of vapor is relatively inexpensive and non-toxic. In particular, the present invention provides a unique process for improving the quality of smoke from tobacco stalks by introducing the tobacco, burley or cured shoots in the area containing the tobacco, heating the containment area when closed to carry to the stems at a temperature in the range of approximately 200-400 psig = 198 ° C to 231 ° C, 180-340 psig = 193-223 ° C at high pressure (200-400 psig) for a sufficient period of time ( approximately 1 to 8 minutes), followed by prompt and rapid decompression of the pressurized steam in the area containing the tobacco and the arrest of the tobacco stems to cause the plant cells to explode so that the lignocellulose in the fibers of the tobacco is modified. tobacco stems and, in turn, reducing negative contributors to the sensory properties of the smoke while producing improved tobacco flavoring compounds. The resulting materials, depending on different time and pressure conditions, vary in fibrous separation to gelatinous form and are more aromatic than untreated untreated stems. The aromas are generally described as chocolate, vanilla, caramel, prune, pumpkin, wine, bread, toast and coffee. Additionally, subsequent laboratory analyzes have found substantial changes in the chemical construction of tobacco stems after the steam explosion, to say the exploded stems seem to have high levels of furan derivatives, carboxylic acids, alcohols and phenols. It has also been found that the steam explosion of the shot-cured stems generates additional sugars and contains other water-soluble lignin decomposition products. In addition to the steam explosion of tobacco stems, chemical additives may be applied to the tobacco stems prior to vapor impregnation to catalyze the production of favorable flavoring compounds. In particular, it has been found that ammonia in the diammonium phosphate form is beneficial, especially for shoot-cured stems. It has been found that organic acids, such as lactic acid, improve burley stems, whereas it has been found that citric and lactic acid catalyze the decomposition of biopolymers, resulting in observations of irritation by inhalation of diminished smoke. It has been found that potassium carbonate catalyses the formation of vanilla-type flavoring compounds, although salts of other weak acids and strong bases may also be used, and sources of alkaline ammonia, such as ammonium bicarbonate, have been found. , and urea, create sensory properties similar to those of diammonium phosphate, and can also soften cellulose, and it has even been found that acid ammonia in the form of diammonium citrate, catalyzes the hydrolysis of hemicellulose into sugars, which subsequently react with ammonia to form desirable sugar-ammonium compounds, although other ammonia compounds with appropriate pH levels can be used.Stepically, steamed by-product steams are used to make sheets of thin paper, called leaves. hand, which are cut into strips and mixed with tobacco to make a reconstituted tobacco product. Hand-held leaves made from steamed stems have superior physical properties, such as hardness, strength, elongation, and stiffness, compared to reconstituted tobacco currently commercially available. It is believed that adding lactic acid to burley stems and adding diammonium phosphate to stems cured in shot before steam blasting can be very useful to produce desirable sensory effects on tobacco stems and reconstituted paper products made from same. Various other features of the present invention will become obvious to one skilled in the art after reading the novel description indicated herein. BRIEF DESCRIPTION OF THE DRAWINGS Reference is made to the drawings which describe an advantageous embodiment of the present invention: Figure 1 is a schematic flow diagram of an apparatus which can be used to carry out the inventive process; and Figure 2 is a schematic flow diagram of an alternative apparatus which can be used to carry out the inventive process also using ammonia. Reference is made to Figure 1 which shows the preferred embodiment of the process of the invention. The tobacco stems to be exploited are deposited in a foraminous basket type screen, of flow passage (not shown). The basket is then placed in a container or impregnator 2 and the lid thereof is sealed to prevent leakage. A steam source 10 is provided, such as a boiler or any high pressure steam system capable of generating superheated steam at pressures of at least 400 psig and temperatures of 225 ° C. A vapor trap 8 is used in the steam addition system to remove excess unwanted condensate from the steam line such that the condensate does not flow into the impregnator 2. A vacuum source 15 is provided to assist in the evacuation of gases after the explosion and controlled by the valve 2. The exhaust valves 13 and 14 are specially constructed to allow the quick and rapid decompression of the vapor pressure releasing and rapidly evacuating the gases contained in the impregnator 2. Exhaust line 23 connects both exhaust valves 13 and 14 to an exhaust blower 24 which also assists in the decompression and evacuation stage. In operation, the main steam valve 7 is opened to make available the live steam from the steam source 10 for impregnation of the tobacco in the sealed container. With valves 9, 11, 12, 13 and 14 closed, valves 16 and 17 are opened to introduce steam into the sealed container. It is allowed to continue the steam flow in the impregnator 2 until the desired pressure is in the range of 200 to 400 psig, as indicated by the pressure indicator 22, and the desired temperature is brought to a range of 193 ° C to 223 ° C, as indicated by temperature indicator 25. When the desired pressure and temperature have been reached and the tobacco has been treated for the desired residence time, in the range of 64 to 448 seconds, the valve 19 is closed and the valves 9, 13 and 14 are opened to evacuate or depressurize immediately the impregnador 2. The decompression to the environment takes from approximately 20 seconds. During the impregnation of the tobacco, the steam is forced to enter the cell walls of the fibers of the tobacco stems. The plant cell walls are constructed of lignocellulose, which is composed of lignin, a complex polymeric substance, which is combined with cellulose, a fibrous carbohydrate, to thicken and harden the cell walls. After the introduction of superheated steam, the steam reacts with and fragments the biopolymers that form lignocellulose. Then, after the rapid and rapid decompression of impregnator 2, some of the cells explode, destroying the intimate chemical association between lignin and cellulose. The vacuum valve 9 is opened and the cover of the impregnator 2 is removed to let out any remaining gases, and the arrest takes place whereby the material cools rapidly. The material is then dried for further processing to the hand sheets, described above, which are cut into strips and added to tobacco blends to make a reconstituted tobacco product suitable for a smoking article. Figure 2 describes another preferred embodiment, but with a united ammonia supply system which introduces ammonia gas from tank 5 into the atmosphere of impregnator 2, under conditions described above. The tobacco stems are similarly placed in a screen basket (not shown) and inserted in the impregnator 2 and the lid thereof is sealed to prevent leakage. With valve 3 closed, the main ammonia gas valve 4 opens. At a pressure of approximately 120 to 130 psig, as shown in the pressure indicator 6, the ammonia gas is introduced into the containment zone. The steam main valve 27 is opened to allow the superheated live steam from the steam source 10, at 200 to 400 psig, to be available for impregnation. With the valves 9, 11, 12, 13 and 14 closed, valves 16 and 17 are opened. It is indicated that the valve 18 serves as a check valve to prevent retrograde flow of gases to the ammonia tank 5. The valves 3 and 19 are open to allow the ammonia gas and steam to flow respectively to these valves in the impregner 2, which contains the screen basket of the tobacco stems, in which the ammonia gas is indicated by the rotometer 21. The flow of both gases in the impregnator 2 is allowed to continue until the desired pressure is in the range of 200 to 400 psig, as indicated by the pressure indicator 22. The temperature of the tobacco is brought to the desired temperature in the range of 193 ° C to 223 ° C, as indicated by the temperature indication 25, and is maintained for a preselected residence period in the range of approximately 1 to 8 minutes. . After this, the valves 3 and 19 are closed and the exhaust valves 13 and 14 are opened to allow quick and ready decompression of the impregnator 2, as described above. Also as indicated above, line 23 connects both exhaust valves 13 and 14 to a common exhaust blower 24 which assists in the rapid depressurization stage. After depressurization, the tobacco stems are removed and processed for inclusion in smoking articles. In both preferred embodiments above, the tobacco stems to be processed may be pretreated with sugar, diammonium phosphate, or citrus pectin, or other chemical additive, and other chemicals as described above, or any combination thereof, before being placed in the impregnator 2. Various examples and resulting tables for processing various tobacco stems according to the process and variations thereof are described hereinafter, already using the equipment modality of Figures 1 or 2. EXAMPLE I A first sample of untreated untreated tobacco stems, burley d cured in shot, which has a moisture content of about 12% by weight, is introduced into impregnator 2, or reaction vessel, which is then sealed. Saturated steam is introduced at temperatures of 215 ° C to 223 ° C in the reaction vessel and is maintained for approximately 64 to 448 seconds at a pressure of 200 to 400 psig. The pressure is then suddenly released within 20 seconds to the environment causing the cells to explode and separate the fibers. The resulting products exhibit sweet aromas reminiscent of chocolate, vanilla, bread, plum, caramel, wine, coffee and pumpkin. In addition, the cigars incorporating the tobacco product of the first sample have less irritation and more total taste than the cigarettes prepared "with the same tobaccos as in the example, but excluding the reconstituted tobacco made with Example 1. EXAMPLE II Two batches of tobacco stems, one of burley and one of tobacco cured in draft, are treated with a solution of diamonium phosphate at 1.25% .The batches are then treated in a temperature range of 193 ° C to 223 ° C for about 3 hours. minutes, then decompress at ambient pressure within approximately 30 seconds.The resulting materials vary from fibrous to almost gelatinous depending on conditions and startle by being more aromatic than unprocessed stems, having aromas described as chocolate, vanilla, caramel, plum Raisin, pumpkin, wine, bread, toast and coffee, subsequent analytical results indicate high levels of furan, carboxylic acid, alcohol derivatives holes and phenols. In addition to high levels of sugars in burley stems. Dry stems are steam dried, both burley and cured in shot, at 50 ° C cut and included in levels at 25% by weight in a test mixture of a tobacco for cigar and is smoked by members of a control group. It is found that cigars that incorporate burley stems and shot cured, pretreated with diammonium diphosphate, have more body, better taste of tobacco and less irritation. It is found that stems exploded with steam cured in shot, pretreated with ammonium carbonate are preferred, the product showing more impact, irritation and body, and better taste of the tobacco. It is also found that the burley stems and cured in draft, without pretreatment with chemical additives, are preferred over the control sample with more body, better flavor of the tobacco, and equal impact and irritation. Finally, the stems of burley tobacco exploited with steam, pretreated with lactic acid, are preferred over the control sample with better flavor of the tobacco and less impact, irritation and body. It is understood that various changes can be made by one skilled in the art in one or more of the various steps of the inventive method described herein without departing from the scope or spirit of the present invention.

Claims (13)

1. REINFORCEMENTS OF THE INVENTION 1. A process for exploiting tobacco stems to improve smoke quality, comprising the steps of: Depositing the tobacco stems in the sealed container: Treating the tobacco stems with superheated steam for a sufficient period of time so that the steam penetrates the cells of the tobacco stems; Quickly decompress the sealed container to cause the cells of the tobacco stems to explode; and Removing exploited tobacco stems from the sealed container characterized in that decompression occurs rapidly in less than 20 seconds.
2. 2. The process according to claim 1, characterized in that the superheat temperatures are approximately 193 ° C to 223 ° C.
3. 3. The process according to claim 1, characterized in that the high pressures are approximately 200 to 400 psig.
4. 4. The process according to claim 1, characterized in that the time periods are approximately 10 to 8 minutes.
5. 5. The process according to claim 1, characterized in that the saturated vapor pressures are varied to reduce the negative contributors to the quality of the smoke.
6. 6. The process according to claim 1, characterized in that the period of time is varied to reduce the negative contributors to the quality of the smoke.
7. The process according to claim 1, characterized in that the tobacco stems are pretreated with chemical additives to form favorable flavoring compounds.
8. The process according to claim 1, characterized in that the chemical additives are ammonia source materials selected from the group consisting of ammonium bicarbonate, urea, diammonium phosphate, diammonium citrate, gaseous ammonia and combinations thereof.
9. 9. The process according to claim 1, characterized in that the chemical additives are organic acids selected from the group consisting of lactic acid, citric acid and malic acid.
10. 10. A process for exploiting tobacco stems to improve the quality of the smoke and form favorable flavoring compounds, characterized in that it comprises the steps of: Depositing the tobacco stems in the sealed container: Treating the tobacco stems with superheated steam at pressures of 200 to 4000 psig for a period of time of 1 to 8 minutes; Quickly decompress the saturated steam from the sealed container; and Removing the stems from the sealed container characterized in that the stems are treated with selected chemical additives before depositing the tobacco stems in the sealed container.
11. 11. The process according to claim 11, characterized in that the chemical additives are sources of ammonia.
12. 12. The process according to claim 11 characterized in that the chemical additives are organic acids.
13. 13. The process in accordance with the claim 11, characterized in that the decompression includes decompression to the environment in a range of approximately 20 seconds.