Systems and Apparatus for Reducing Tobacco-Specific Nitrosamines in Dark-Fire Cured Tobacco Through Electronic Control of Curing Conditions

Abstract

The present invention relates to systems and apparatus for dark-fire curing of tobacco. Specially, the present invention provides a central control system for controlling and adjusting conditions within a structure utilized for curing dark-fired tobacco, for example by remotely turning the ventilation fan on or off. Additionally, the invention provides for an external smoking structure incorporated into the control system. This allows for simultaneous control of external smoking, that is smoking that is physically separated from curing, and the transportation of smoke into the into the dark-fire curing structure, in addition to the control of the curing structure itself.

Claims

1. A central control system for use with dark-fire curing of tobacco comprising: a plurality of sensors distributed throughout a dark-fire curing structure; at least one communication link between the plurality of sensors and the central control system; the central control system operable to provide a command to at least one apparatus of the dark-fire curing structure by a communication link wherein the dark-fire curing structure is connected to an external smoking structure by a hollow structure; an actuatable and openable barrier positioned between the dark-fire curing structure and the external smoking structure.

2. The central control system of claim 1, wherein the plurality of sensors measure a dry bulb temperature, a wet bulb temperature, and/or relative humidity.

3. The central control system of claim 1, wherein the apparatus of the dark-fire curing structure is a ventilation fan and the command between the central control system and the apparatus of the dark-fire curing structure is a command that the ventilation fan be set to one of turned on, turned off or a change of fan speed.

4. The central control system of claim 1, wherein the apparatus of the dark-fire curing structure is an air intake vent and the command between the central control system and the apparatus of the dark-fire curing structure is an open/close command.

5. The central control system of claim 4, wherein the command specifies a degree of openness.

6. The central control system of claim 1, wherein the apparatus of the dark-fire curing structure is a heat/smoke source and the command between the central control system and the apparatus of the dark-fire curing structure provides that the heat/smoke source be turned one of on or off.

7. A central control system for use with dark-fire curing of tobacco comprising: a plurality of sensors distributed throughout a dark-fire curing structure; the plurality of sensors in communication with the central control system; a user operated external device in communication with the central control system and operable to transmit a command to the central control system; an apparatus of the dark-fire curing structure in communication with the central control system; the apparatus of the dark-fire curing structure being at least one of an air intake vent and a ventilation fan; wherein the central control system is operable, based upon the plurality of sensor data, to control at least one of the ventilation fan, the air intake vent and an actuatable and openable barrier between the dark-fire curing structure and an external smoking structure.

8. The central control system of claim 7, wherein the plurality of sensors measure at least one of a dry bulb temperature, a wet bulb temperature and relative humidity.

9. The central control system of claim 7, wherein the user operated external device is selected from a group consisting of a smartphone, a smart watch, a tablet, or a computer.

10. The central control system of claim 7, wherein the user operated external device is operable to send a command to the central control system, the command indicating that at least one ventilation fan be turned on/off.

11. The central control system of claim 7, wherein the user operated external device is operable to send a command to the central control system, the command indicating that at least one air intake vent be opened/closed.

12. The central control system of claim 11, wherein the command that the air intake vent be opened/closed specifies a degree of openness.

13. The central control system of claim 7, wherein the user operated external device is operable to send a command to the central control system, the command indicating that the actuatable and openable barrier be closed.

14. A central control system for use with dark-fire curing of tobacco comprising: a plurality of sensors distributed in a dark-fire curing structure; a plurality of sensors distributed in an external smoking structure; a central control system; the plurality of sensors of the dark-fire curing structure in communication with the central control system; the plurality of sensors of the external smoking structure in communication with the central control system; the central control system in communication with at least one apparatus of the dark-fire curing structure; wherein the at least one apparatus of the dark-fire curing structure is at least one of a ventilation fan and an air intake vent opening.

15. The central control system of claim 14, wherein the system further comprises: a user operated external device in communication with the central control system and; the user operated external device providing one of a plurality of commands to the central control system.

16. The central control system of claim 15, wherein the user operated external device is selected from a group consisting of a smartphone, a smart watch, a tablet, or a computer.

17. The central control system of claim 14, wherein the plurality of sensors measure a dry bulb temperature, a wet bulb temperature, and/or relative humidity.

18. The central control system of claim 14, wherein the communication between the central control system and at least one apparatus of the dark-fire curing structure includes a command representative of at least one ventilation fan be turned on/off.

19. The central control system of claim 14, wherein the communication between the central control system and at least one apparatus of the dark-fire curing structure comprises a command that at least one air intake vent be opened/closed.

20. The central control system of claim 19, wherein the command that the air intake vent be opened/closed specifies a degree of openness.

21. The central control system of claim 14, wherein the communication between the central control system and at least one apparatus of the dark-fire curing structure comprises a command that at least one heat/smoke source be turned on/off.

22. The central control system of claim 14, wherein the external smoking structure includes: an external structure for smoking; and a hollow enclosure further including a first open end connected to the external structure for smoking and a second open end connected to a dark-fire curing structure.

23. An external smoking structure for use with dark-fire curing of tobacco comprising: an external structure for smoking; a smoke generator; a plurality of sensors distributed throughout the external structure; a hollow enclosure further including a first open end and a second open end; wherein the first open end connects to the external structure for smoking and the second open end connects to a structure for dark-fire curing of tobacco; an actuatable and openable barrier such that smoke generated by the external structure for smoking may be imported from the external structure for smoking to the structure for dark-fire curing; wherein the structure for dark-fire curing includes an air intake vent and a ventilation fan; and a remote device in communication with the plurality of sensors and in controlling communication with at least one of the air intake vent, the ventilation fan and the barrier in the hollow enclosure.

24. The external smoking structure of claim 23, wherein the hollow enclosure further comprises a plurality of actuatable and openable barriers to allow or prevent the smoke generated in the external structure to enter the hollow enclosure and/or curing structure.

25. The external smoking structure of claim 23, wherein the hollow enclosure further comprises a filter that the smoke generated in said external smoking structure passes through to remove solid particles from the smoke.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] FIG. 1 is an elevational view of a dark-fire curing barn equipped with the central control system of the present invention.

[0032] FIG. 2 is a flowchart illustrating an embodiment of the process of control utilizing the central control system of the present invention.

[0033] FIG. 3 is a flowchart illustrating an embodiment of the process of control utilizing the central control system of the present invention.

[0034] FIG. 4 is an elevational view of a dark-fire curing barn and external smoking structure equipped with the central control system of the present invention.

DETAILED DESCRIPTION OF DRAWINGS

[0035] The present invention now will be described more fully hereinafter. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. As used in this specification and the claims, the singular forms a, an, and the include plural referents unless the context clearly dictates otherwise.

[0036] The selection of the plant from the Nicotiana species can vary; and in particular, the types of tobacco or tobaccos may vary. Descriptions of various types of tobaccos, growing practices and harvesting practices are set forth in Tobacco Production, Chemistry and Technology, Davis et al. (Eds.) (1999), which is incorporated herein by reference. Various representative types of plants from the Nicotiana species are set forth in Goodspeed, The Genus Nicotiana, (Chonica Botanica) (1954); U.S. Pat. No. 4,660,577 to Sensabaugh, Jr. et al.; U.S. Pat. No. 5,387,416 to White et al. and U.S. Pat. No. 7,025,066 to Lawson et al.; US Patent Appl. Pub. Nos. 2006/0037623 to Lawrence, Jr. and 2008/0245377 to Marshall et al.; each of which is incorporated herein by reference. Of particular interest are N. alata, N. arentsii, N. excelsior, N. forgetiana, N. glauca, N. glutinosa, N. gossei, N. kawakamii, N. knightiana, N. langsdorffi, N. otophora, N. setchelli, N. sylvestris, N. tomentosa, N. tomentosiformis, N. undulata, and N. x sanderae. Also of interest are N. africana, N. amplexicaulis, N. benavidesii, N. bonariensis, N. debneyi, N. longiflora, N. maritina, N. megalosiphon, N. occidentalis, N. paniculata, N. plumbaginifolia, N. raimondii, N. rosulata, N. rustica, N. simulans, N. stocktonii, N. suaveolens, N. tabacum, N. umbratica, N. velutina, and N. wigandioides. Other plants from the Nicotiana species include N. acaulis, N. acuminata, N. attenuata, N. benthamiana, N. cavicola, N. clevelandii, N. cordifolia, N. corymbosa, N. fragrans, N. goodspeedii, N. linearis, N. miersii, N. nudicaulis, N. obtusifolia, N. occidentalis subsp. hersperis, N. pauciflora, N. petunioides, N. quadrivalvis, N. repanda, N. rotundifolia, N solanifolia and N. spegazzinii.

[0037] Nicotiana species can be derived using genetic-modification or crossbreeding techniques (e.g., tobacco plants can be genetically engineered or crossbred to increase or decrease production of certain components or to otherwise change certain characteristics or attributes). See, for example, the types of genetic modifications of plants set forth in U.S. Pat. No. 5,539,093 to Fitzmaurice et al.; U.S. Pat. No. 5,668,295 to Wahab et al.; U.S. Pat. No. 5,705,624 to Fitzmaurice et al.; U.S. Pat. No. 5,844,119 to Weigl; U.S. Pat. No. 6,730,832 to Dominguez et al.; U.S. Pat. No. 7,173,170 to Liu et al.; U.S. Pat. No. 7,208,659 to Colliver et al.; and U.S. Pat. No. 7,230,160 to Benning et al.; US Patent Appl. Pub. No. 2006/0236434 to Conkling et al.; and PCT WO 2008/103935 to Nielsen et al.

[0038] For the preparation of smokeless and smokable tobacco products, it is typical for harvested plants of the Nicotiana species to be subjected to a curing process. Descriptions of various types of curing processes for various types of tobaccos are set forth in Tobacco Production, Chemistry and Technology, Davis et al. (Eds.) (1999).

[0039] The Nicotiana species can be selected for the type of biomass or anatomical part that it produces. For example, plants can be selected on the basis that those plants produce relatively abundant biomass or seed, produce biomass or seed that incorporate relatively high levels of specific desired components, and the like.

[0040] The Nicotiana species of plants can be grown under agronomic conditions so as to promote development of biomass or one or more anatomical parts. Tobacco plants can be grown in greenhouses, growth chambers, or outdoors in fields, or grown hydroponically.

[0041] The time of harvest during the life cycle of the plant can vary. For example, biomass or one or more anatomical parts can be harvested when immature. Alternatively, biomass or one or more anatomical parts can be harvested after the point that the plant has reached maturity. However, generally tobacco biomass to be cured via dark-fire curing is harvested when the leaves are mature.

[0042] Turning now to FIG. 1, which illustrates an embodiment of a typical dark-fire curing barn and the electronic control system of the present invention. The dark-fire curing barn 100 includes an internal skeletal framework, including a plurality of vertical support members 110 adjoined by a plurality of horizontal cross members 112, which may also serve as support for hanging tobacco 120. While only a portion of FIG. 1 is shown housing tobacco it is understood to those skilled in the art that a typical dark-fire barn in use may be completely full of tobacco hanging downward from the internal horizontal cross members 112. It may also be understood that it may be preferred for the barn to be completely full. The internal structural framework of the barn is covered by walls 114 and by a roof 116. As is typical of dark-fire curing barns, at least one ventilation fan 130 is present to provide air circulation and promote venting during the curing process. In some embodiments, particularly larger barns with multiple rooms, a plurality of fans may be preferred. Additionally, the barn has a plurality of fresh air intake vent or dampers 140 that may be operatively opened or closed in order to provide fresh air to the barn during the curing process (shown in the open position in FIG. 1).

[0043] The electronic control system of the present invention may be retrofitted into existing dark-fire curing barns, as depicted in FIG. 1, or may be incorporated into the new construction of a dark-fire curing structure. The electronic control system may have a plurality of temperature and relative humidity sensors 150 be distributed throughout the curing structure. These sensors measure the temperature and relative humidity of the air of their respective locations of the curing barn. The sensors are capable of measuring both the dry bulb and wet bulb temperatures. A dry bulb temperature, or ambient air temperature, is measured without regard to the moisture content of the air. A wet bulb temperature, in contrast, measures what the air temperature in a particular area would be if it were cooled to 100% relative humidity by the evaporation of water into it, or the lowest temperature that can be reached under the current environmental conditions by evaporation of water alone. These sensors are operatively connected to a central control system 160, which may be located within the curing structure or, as depicted in FIG. 1, outside of the curing structure. Sensors may be connected to the control system through a wired or wireless connection. The central control system 160 may also be operatively connected to other structures of the curing barn, including the ventilation fan(s) 130, fresh air intake vents or dampers 140, and/or the heat/smoke source for the barn (for example, an external smoking structure). The heat source in FIG. 1 is a smoking fire 170 at the base of the barn. These smoking fires in dark-fire curing structures may be controlled fires lit on a concrete base of the barn. Alternatively, the smoking fire may be lit within a pit dug in the earthen base of the barn. In another embodiment, that will be explained in greater detail later, the fire and smoke generation may be located externally, or physically separate from the curing structure.

[0044] As shown in FIG. 2, the central control system 160 may communicate through sending a wireless signal 212 with a plurality of other wirelessly connected devices 210. Wirelessly connected devices may be, for example, from a group consisting of a smartphone, a smart watch, a tablet, or a computer. The wireless connectivity allows for the operator (often a farmer) to monitor temperature and humidity conditions inside the curing barn live from a remote location, such as their home, office, or in the field. After viewing a live reading, the operator may select, remotely through the control system, to turn a ventilation fan 130 on/off, temporarily open the air intake vents or dampers 140, or (where connected to the system) turn the heat/smoke source on/off by sending a wireless signal 214 to the control system 160. This allows for the operator to obtain finer, real-time, control of temperature and humidity conditions within the barn from a remote location.

[0045] Additionally, or alternatively, the central control system 160 may be pre-programmed by the operator. Preprogramming may include programming the system to perform particular actions or inactions when particular conditions are met. For example, the system may be preprogrammed to push an alarm to the operator's electronic device if the temperature inside the curing structure reaches above a particular point. FIG. 3 use a flow chart to illustrate this process, where the sensors 150 take temperature and humidity measurements, which are electronically transmitted 310 to the central control system 160. The control system is operable to compare measured values to programmed threshold parameters which cause action or inaction. Where preprogrammed thresholds are met, a signal 320 is sent to the corresponding apparatus, for example to the ventilation fan 130 or to the air intake vent or damper 140. As an illustrative example, the control system may be preprogrammed that if the temperature sensors measure a dry bulb temperature of greater than 130 F. then the air intake vents or dampers should be opened for a set period of time, for example 15 seconds. Additionally, the central control system may be programmed to recheck sensor measurements a set period of time following an action generated by a preprogrammed threshold and repeat the action until the threshold parameter is no longer met. As an illustrative example, the control system may be programmed to recheck the sensors' temperature measurements 15 minutes following the opening of the air intake vents or dampers.

[0046] Alternatively, the control system may be preprogrammed to allow particular actions or inactions for a set time period, thus functioning similarly to a timer. It will be recognized by those of skill in the art that the central control system of the present invention may be preprogrammed any way such as to increase control, particularly over the parameters of temperature and humidity, of the curing process.

[0047] An alternative embodiment of the control system may incorporate external fire and smoke generation system, which is physically separate from the curing structure. The central control system may generally control the external smoke system itself, as well as the input from the external smoke system to the curing structure. As illustrated in FIG. 4, the external smoking structure 400 is physically separated from the curing structure 100. The physical distance between the barn and smoking structure is irrelevant, and may be long or may be short (as pictured). The two physically separated structures may be connected by a hollow enclosure 410 with two opposing open ends. The enclosure contains a first open end 412 that connects to the external smoking structure 400, and a second open end 414 that connects to the curing structure 100. Those of skill in the art will recognize that a plurality of hollow enclosures may be used to connect the external smoking structure to the curing structure, and may include, for example, piping or tubing.

[0048] Smoke may be generated inside of the external smoking structure by any means known in the art, including, for example, wood burning, friction smoking, or use of smoke condensate. Smoking 440 for dark-fire curing, as shown in FIG. 4 traditionally uses wood burning 450, which involves use of hardwood slabs or sawdust. Hardwoods are preferred for smoking, as they burn slower and more evenly than softer woods. Friction smoking involves a large wood block being pressed against a rotating metal wheel, which generates friction heat and causes the wood to slowly burn and mildly smoke. Smoke condensates are produced by smoldering wood shavings, condensing the resulting smoke in water, and cleaning the condensed smoke. The condensed smoke is regenerated for smoking and atomized in the smoking structure. Friction smoking and use of smoke condensate both contain lower levels of polycyclic aromatic hydrocarbons (PAHs) as compared to traditional smoking methods, and therefore may be preferable over traditional wood burning. Once generated by the method chosen, smoke may flow from the external smoking structure 400, through the hollow enclosure 410 to the curing structure 100.

[0049] Sensors 150, like those installed in the curing barn, are distributed throughout the external smoking structure. In addition to measuring temperature and humidity, the sensors inside of the smoking structure may also measure additional variables, such as the amount of smoke generated. Also like the sensors in the curing structure, these sensors are connected to the central control system 160. The control system may wirelessly communicate with the smoking structure and turn the heat/smoking element on/off depending on the conditions and needs of the curing barn. For example, if friction smoking is being utilized in the smoking structure the control system may send a signal to the metal wheel generating the friction to stop the spinning, and thus stop the generation of smoke. Utilizing a central control system and allowing communication with an external smoking structure allows for control of the amount of smoke generated.

[0050] Returning to FIG. 4, an actuatable and openable barrier 420 exists positioned between the curing structure 100 and the external smoking structure 400 (shown in the closed position). While shown in FIG. 4 as being placed within the hollow enclosure 410, those of skill in the art will recognize the actuatable and openable barrier may alternatively be placed at either end of the hallow enclosure. The actuatable and openable barrier 420 may be any type of solid barrier that prevent smoke from permeating through it, for example various metals. The central control system may control the opening and closing of the barrier through communications via wireless signals based on either preprogrammed parameters or operator command. Additionally, the barrier may be capable of opening and closing to varying degrees controlled by the central control system so that more or less smoke can be allowed into the curing structure depending on the how open or closed the barrier may be.

[0051] Since smoke generated by traditional wood burning may release nitrous oxide (N.sub.2O) gases, which react with secondary alkaloids in tobacco to form tobacco specific nitrosamines, the use of alternative smoking methods, such as friction smoking or using smoke condensate, may aid in prevention of TSNAs formation. Additionally, physical separation of the smoking structure and the curing structure allows for the smoke to be cleaned prior to entering the curing structure where it may react with tobacco. As shown in FIG. 4, such cleaning may include the smoke passing through a filter 430 in order to filter out solid particles such as soot, ash, or charcoal. Other methods of cleaning smoke (not shown in FIG. 4) prior to it entering the curing chamber may include chemical treatment or washing of the smoke.

[0052] Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing description. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.