CN100430001C

CN100430001C - Tobacco treatment

Info

Publication number: CN100430001C
Application number: CNB018063721A
Authority: CN
Inventors: K·G·麦克亚当; D·奥雷利; A·J·曼森; I·G·M·安德森
Original assignee: British American Tobacco Co Ltd
Current assignee: British American Tobacco Investments Ltd
Priority date: 2000-03-10
Filing date: 2001-03-06
Publication date: 2008-11-05
Anticipated expiration: 2021-03-06
Also published as: RU2002125119A; DK1267650T3; CN1438843A; CA2400408A1; JP3931084B2; WO2001065954A1; RU2259797C2; ATE313968T1; BR0109264A; MY136703A; NZ521065A; BR0109264B1; EP1267650A1; EG22308A; AU3586301A; ES2251464T3; AU2001235863B2; JP2003526345A; DE60116273D1; EP1267650B1

Abstract

The invention relates to a method of treating tobacco to reduce or eliminate nitrosamines therefrom. The method comprises the use of a supercritical fluid extraction medium at elevated temperature and pressure to selectively remove nitrosamines compared with nicotine removal. The nitrosamine content for all tobacco types can be reduced.

Description

The processing of tobacco

The present invention relates to a kind of method of handling tobacco with the content that reduces or eliminates nitrosamine wherein, particularly tobacco-specific nitrosamine.

Tobacco-specific nitrosamine comprises N '-nitrosonornicotine, 4-(methyl nitrosamino-)-1-(3-pyridine radicals)-1-butanone, N '-nitroso anatabine and N '-nitroso anabasine.

Known have variety of processes to remove nitrosamine from tobacco.At US 5,803,081 and WO 98/58555 in, greenery tobacco (that is, slaking before tobacco) is accepted microwave radiation, Convective Heating or freeze drying and handles so that kill and be considered to cause the tobacco microorganism that nitrosamine generates between the maturation period.A shortcoming of this kind method is, this method comprises the requirement of tobacco being implemented special slaking, and this kind ageing method will carry out at the commitment after the tobacco results.

The purpose of this invention is to provide a kind of modification method that reduces content of nitrosamines in the tobacco.

Another object of the present invention provides a kind of modification method that optionally reduces nitrosamine in the tobacco.

The invention provides a kind of method for treatment of tobacco, wherein tobacco is accepted the processing of supercritical fluid extraction medium, so that extract nitrosamine from described tobacco.

Preferably, handle, nitrosamine is separated from the supercritical fluid extraction medium by making this spe medium remove through nitrosamine.

Suitable is that nitrosamine is removed to handle and can be comprised a kind of chemisorbed step.Preferably, the chemisorbed step can comprise a kind of use of ion-exchanger.

Alternatively, nitrosamine is removed to handle and can be comprised adsorption step.Suitable adsorbent can be selected from one or more in the middle of bead, active carbon, alumina silicate and the zeolite.Other suitable adsorbent well known by persons skilled in the art also can use.

In another kind of replacement scheme, nitrosamine removal processing can comprise makes spe medium handle with ultraviolet light (UV), causes the decomposition of nitrosamine in the spe medium.

Another replacement scheme comprises, by be settled out nitrosamine from spe medium, decomposes by making spe medium generation nitrosamine specific enzymes, perhaps removes nitrosamine by chromatogram art or other method well known by persons skilled in the art.

In the nitrosamine removal method that the method for removal nitrosamine is summarized above can comprising from spe medium more than one.In some occasion, at least in the occasion that adopts multiple removal method (comprising multistep processes altogether), the special effect that nitrosamine is removed will be improved.For example, nitrosamine removal method can be a multistep processes, comprises that the chemisorbed step combines with treatment with ultraviolet light or subsequently with treatment with ultraviolet light.Before treatment with ultraviolet light, may need washing step so that from chemical adsorption medium, remove nitrosamine, and then washings are applied UV-irradiation.Water, acid, salting liquid or alcohol may all be applicable in this washing step.

Suitable is, spe medium can (again) contact with tobacco after therefrom removing a part (if not whole words) nitrosamine, and nitrosamine extract in addition is able to combine or combination again with tobacco in the medium so that make.These extracts for example can comprise nicotine and/or fragrance matter.

Very preferably, used supercritical fluid is a supercritical carbon dioxide, although other supercritical fluid well known by persons skilled in the art also is suitable.

Suitable is, acid, and preferred organic acid joined in the tobacco before with the treatment with supercritical fluid tobacco.Alternatively, this acid also can combine with supercritical fluid.In addition, when having ion-exchanger or sorbent material, this acid can combine with ion-exchanger or adsorbent.Suitable acid can be organic acid, is selected from malonic acid, ascorbic acid, butanedioic acid, glutaric acid, adipic acid, malic acid, tartaric acid, glactaric acid and citric acid or their salt derivative.Preferably, organic acid is a citrate, for example potassium citrate.Other suitable acid can be inorganic acid, for example sulfuric acid and phosphoric acid.Suitable is that when being applied to acid on the tobacco, this acid is the solution form.This kind solution can take spraying to apply.Advantageously, acid is carried out to being applied in tobacco industry custom is used for applying shell (casing) on tobacco the shell cylinder on the tobacco.

Other modifier, for example organic solvent or alcohol also can be used as substitute or additives and use.

Preferably, tobacco occurs under the pressure and temperature of raising with the extraction processing that supercritical fluid carries out.Suitable is when supercritical fluid is carbon dioxide, can adopt the pressure of 100～350bar, the pressure of preferred about 200～300bar, more preferably from about 240～260bar.Preferably, used temperature is greater than about 35 ℃, and more preferably from about 35～about 140 ℃, further preferred about 35～about 90 ℃.

Advantageously, during handling with supercritical fluid extraction, tobacco is placed in the closed indoor or pressure pan.

Heating can be by conducting heat or being undertaken by electromagnetic radiation (that is microwave or radio frequency heating).When adopting electromagnetic radiation, sealing chamber or pressure pan must be made by non-electromagnetic absorber certainly, and for example nonmetallic materials are also wanted to tolerate this operating pressure simultaneously.This type of suitable material can comprise poly-fluorohydrocarbon material, for example Teflon (trade name).

The technique effect that removes tobacco-specific nitrosamine with the treatment with supercritical fluid tobacco still belongs to unknown so far.Very preferably, with supercritical fluid the condition that tobacco extracts processing is partial to nitrosamine is extracted in the supercritical fluid, and this kind deflection is and other peculiar compound, comparatively speaking as nicotine and so on.Advantageously, do not have or seldom have nicotine to be moved out to the spe medium from tobacco.The condition of deflection nitrosamine extraction (for the nicotine extraction) comprising: the pH value of tobacco is less than about 6.5, preferably less than about 5.5.

Preferably, after tobacco was handled through the inventive method, its nitrosamine reduced ratio that percentage and nicotine reduces percentage between about 1.1: 1～18: 1, more preferably is 1.3: 1～about 10: 1, more preferably from about 2: 1～about 6: 1.

For one group of given treatment conditions, comprise for example spe medium mass flow of unit mass tobacco, begin through between nitrosamine percent extraction (bigger) and nicotine percent extraction (less), maximum difference occurring behind the interval after a while from processing procedure.Therefore, preferably just interrupting extraction before and after at the moment or this moment handles.

The suitable supercritical fluid extraction mass of medium flow of every kilogram of tobacco is between about 1kg/h～about 55kg/h, and this depends on process conditions, for example the size of bulk density of indoor tobacco and chamber.Advantageously, every kilogram of supercritical fluid extraction of tobacco mass of medium flow is between about 10kg/h～about 40kg/h, more favourable 15～35kg/h, and further favourable about 30kg/h is although these numerals depend on desired product performance really.

Advantageously, the tobacco of handling by the inventive method is a pipe tobacco, sheet pipe tobacco or bar shaped pipe tobacco.Alternatively or additionally, tobacco can be full wafer leaf tobacco, tobacco end and reconstituted tobacco.

If see fit, then the tobacco of handling by the inventive method can carry out regulating step, thereby water capacity after tobacco is handled is adjusted to less than about 15%, preferably less than 13%.

Use subsequently tobacco under the situation of treatment with supercritical fluid, by making described medium remove to handle through nitrosamine nitrosamine is separated from the supercritical fluid extraction medium, preferably this medium circulates along closed-system.

Suitable is, this closed-system can comprise with first chamber of treatment with supercritical fluid tobacco and be used to carry out nitrosamine removes second chamber of handling, and wherein first and second chambers are connected with each other by interconnection device such as pipeline.This kind system also comprises operation and is used for fluid delivery system that spe medium is circulated along closed-system.Nitrosamine such as ion exchange resin or adsorbent is removed material and can be contained in second chamber, so that the supercritical fluid extraction medium is transferred to second chamber by interconnection device after handling tobacco, therein, nitrosamine is removed fully or basically fully.The supercritical fluid extraction medium can turn back in the tobacco of first chamber after removing nitrosamine.

Suitable is can be provided with a plurality of chambers of using with the treatment with supercritical fluid tobacco that interconnect, and/or can be provided with a plurality of chambers that interconnect of handling of removing for nitrosamine.Be used to handle tobacco an above chamber or be used for nitrosamine remove and handle or be used under the situation of these two kinds of purposes, supercritical fluid can flow through these chambers successively.

Alternatively, closed-system can comprise first or the single chamber with import and outlet device, and wherein interconnection device is connected to each other the import and the outlet device of chamber.Suitable is, interconnection device is used under the fluid delivery system effect supercritical fluid extraction medium transferred to and flow through nitrosamine from the outlet device of chamber removes treating stations, arrives the inlet device of chamber again.Preferably, the Fluid Volume in interconnection device maintains floor level.Nitrosamine is removed material, and for example ion-exchanger or absorbent can be contained in any suitable permeability container, so just provide a kind of usefulness so that fluid can flow through the device and a kind of device in order to prevent that tobacco from contacting with nitrosamine removal material of this container.

Alternatively, nitrosamine is removed and is for example handled and can be made of the conveying of medium through ultraviolet source.In this case, interconnection device must can see through ultraviolet light.

Suitable is to be provided with a plurality of chambers that interconnect with the treatment with supercritical fluid tobacco.

So that extract from tobacco the nitrosamine, tobacco also can be accepted the microorganism deactivation and handle except using the treatment with supercritical fluid tobacco.As mentioned above, microorganism comprises that Enterobacteragglomerans (agglomeration Escherichia coli), spp.Bacillus, Fusarium equisetti (sickle-like bacteria), Cladosporium cladosporoides, Altenaria alternata and Acremonium arxii it is believed that the generation that causes tobacco nitrosamine between the maturation period.In fact, can think that microorganism also is the tobacco duration of storage of slaking generates nitrosamine in tobacco a contribution factor.Therefore, can reduce tobacco in possibility by microbial activity in the microorganism deactivation processing reduction tobacco through extraction back regeneration nitrosamine.The microorganism deactivation is handled and can be carried out before or after tobacco is handled with supercritical fluid.Another kind of replacement scheme is to handle tobacco with supercritical fluid under microorganism deactivation condition, so that microorganism deactivation and extraction are taken place simultaneously.

Suitable is, the microorganism deactivation is handled can comprise pasteurization, and wherein tobacco is heated to set point of temperature and at this temperature maintenance official hour.For example, tobacco can be heated to about 70 ℃～about 150 ℃ temperature and the time of keeping about 30s～about 2min.Heating for example can realize by the modes such as Convective Heating, heating using microwave or radio frequency heating with gaseous state heat medium contact tobacco.

Suitable is, through the water capacity of the tobacco of sterilization treatment can by in advance-or back-regulating step regulated.

Alternatively, tobacco carries out the processing of killing microorganisms with for example ionising radiation, ultra-violet radiation, freeze drying or electron beam, can be used as this microorganism deactivation and handles.

So that extract from tobacco the nitrosamine, tobacco can also be handled through peroxynitrite/nitrate removal except using the treatment with supercritical fluid tobacco.Nitrite is the important as precursors of nitrosamine, and nitrate then is the precursor of nitrite.Can think that after nitrosamine is removed, thereby the residual nitrite in the tobacco can freely react the regeneration nitrosamine with the alkaloid that also exists in tobacco.Nitrite/nitrate removal is handled to be suitable for and is comprised solvent extraction, so that remove nitrite/nitrate from tobacco, carries out ion-exchange subsequently so that fix this nitrite/nitrate.Alternatively, nitrite can be removed by oxidation step.In another kind of replacement scheme, can use the method that adopts removal of microorganisms nitrite/nitrate, for example be disclosed in the arbitrary piece of writing among GB 1 440 171, GB 1 585 024, US 4709,710 or the GB 2 014 031.

Handle equally as the microorganism deactivation, nitrite/nitrate removal processing also can be before tobacco be with treatment with supercritical fluid, afterwards or during carry out.When nitrite/nitrate removal is handled when carrying out simultaneously with the processing of supercritical fluid with tobacco, for removing nitrite from tobacco, this method for example can comprise any step in the following steps: applied ascorbic acid before tobacco is with treatment with supercritical fluid in tobacco; Ascorbic acid is combined with supercritical fluid; Perhaps when having ion-exchanger or adsorbent, make ascorbic acid combine with ion-exchanger or adsorbent.Ascorbic acid has the effect of removing nitrite from tobacco.

Nitrite/nitrate removal is handled the alternative or additional step that can be used as the processing of microorganism deactivation and is implemented.

The inventive method provides a kind of burley, and its about 0.3ppm of initial content of nitrosamines～about 30ppm after slaking is reducing by 45% at least through its content of nitrosamines of processing back.If tobacco is the burley of content of nitrosamines 5～6ppm, then after the processing, this content is preferably 3.6ppm or still less.

The inventive method also provides a kind of Virginia tobacco, and its initial water content after slaking is reducing by 45% less than 8.5ppm at least through its content of nitrosamines of processing back.

Preferably, the content of nitrosamines of finished white rib or Virginia tobacco hangs down 60% at least than its initial content.

The inventive method also provides a kind of U.S. smoking mixture, and its Ninicotine content is 0.10～2.0%; Content of nitrosamines is 0.10～1.2 μ g/g, and after through processing, it is 1: 1～10: 1 with the ratio that nicotine reduces percentage that nitrosamine reduces percentage.

The inventive method also provides a kind of Virginia smoking mixture, and its Ninicotine content is 0.30～2.15%; Content of nitrosamines is 0.10～1.5 μ g/g, and after through processing, it is 1: 1～10: 1 with the ratio that nicotine reduces percentage that nitrosamine reduces percentage.

Preferably, this ratio is 5: 1 or higher, more preferably 8: 1 or higher.

For being expressly understood the present invention and putting into practice easily, below with reference to the accompanying drawings by embodiment, wherein:

Fig. 1 represents to implement the equipment used according to the method for first aspect present invention; And

Fig. 2 represents to implement the equipment used according to the present invention's method on the other hand.

Equipment is a kind of closed-system as shown in Figure 1, comprises first chamber 1 and second chamber 2, first and second chamber wherein, and 1,2 are connected to each other by interconnection pipeline 3.This closed-system also comprises fluid delivery system, and promptly pump 4.This equipment also comprises storage tank 5, links to each other with first Room by pipeline 6.Valve 7 is located in the pipeline 6, and this valve 7 can operate and be used for cutting out storage tank 5.

Example 1

In the operation of Fig. 1 equipment, about 30kg water content is the pipe tobacco of about 14% or 25% (seeing Table 1), puts into first chamber 1, and the volume of this chamber is 150L.A kind of ion-exchanger, that is, acid-exchange resin (by the supply of Bayer company), heavy 4.4kg puts in second chamber 2, and the volume of this chamber is 150L.Ion-exchanger mixes with about 500g solid citric acid k particle.Add carbon dioxide in storage tank 5, this carbon dioxide is pressurizeed by the pump installation (not shown) subsequently, and transfers to first and second chambers by pump installation from

storage tank

5, and 1,2, and interconnection pipeline 3, until the extraction conditions that reaches regulation, that is, pressure equals about 250bar; About 70 ℃ of temperature.This moment, thus shut off valve 7 sealing carbon dioxide storage tanks.Subsequently, supercritical carbon dioxide under pump 4 effect along first chamber 1 (and, therefore pass the tobacco of wherein being equipped with) and flow through second chamber 2 (and, therefore pass ion exchange resin wherein) by interconnection pipeline 3 and circulate.Supercritical carbon dioxide extraction medium is along closed-system circulation 1.5h or 3h.Subsequently, thereby open the pressure that the emptying device (not shown) is removed first and

second chambers

1,2, and open this two chambers.

So nicotine and the content of nitrosamines of the tobacco of handling adopt the proper standard laboratory test to estimate then.

Have been found that this extraction processing of growing tobacco can remove the distinctive nitrosamine of tobacco of suitable vast scale from processed tobacco.Table 1 discloses the processing of tobacco through summarizing above nicotine and the minimizing percentage of nitrosamine in tobacco afterwards.The total carbon dioxide capacity that uses among these embodiment is 2190kg.

Table 1

The test sequence number	The tobacco water capacity	The extraction time (h)	Nicotine reduces (%)	Nitrosamine reduces (%)
The test sequence number	The tobacco water capacity	The extraction time (h)	Nicotine reduces (%)	Nitrosamine reduces (%)	1	14％	1.5	67	90
2	14％	3.0	78.5	94	1	14％	1.5	67	90
2	14％	3.0	78.5	94	3	25％	1.5	65.5	93.5
4	25％	3.0	77	95	3	25％	1.5	65.5	93.5

Compare with the processing of 3h, the nitrosamine quantity percentage that the 1.5h processing is extracted and the difference of nicotine quantity percentage are bigger.

Example 2

Can think the extraction time of summarizing above further to shorten and can the appreciable impact nitrosamine do not reduce percentage, further reduce nicotine simultaneously and reduce percentage.For example, the extraction time can be between about 15min～about 1.5h, preferably between about 20min～about 1h, and 25min～about 40min more preferably from about, further preferred about 30min.

Extraction conditions preferably further is partial to nitrosamine is extracted in the supercritical fluid, for peculiar compound of other tobacco such as nicotine.With regulate the extraction time and with or adopt individually some with remove the peculiar compound of other tobacco and compare other extracting process of removing nitrosamine according to qualifications.For example, the pH value of tobacco can maintain and be lower than about 6.5, preferred about 5.5.According to another kind of replacement scheme, with before pending tobacco contacts, the supercritical fluid extraction medium can be adjusted to full and/or saturated substantially with the peculiar compound of tobacco beyond the nitrosamine or its commercially available analog at spe medium.Another replacement scheme, when supercritical fluid is carbon dioxide, tobacco can be cooled to and be lower than about 35 ℃ temperature, so that when supercritical carbon dioxide pumps to when tobacco indoor is housed, total effectiveness of extraction process descends, but moves towards the preferential direction of the removal that is unfavorable for the nitrosamine peculiar compound of tobacco in addition.The extraction of deflection nitrosamine also can realize by changing (that is, improving) tobacco bulk density in extraction cell.

In addition, deflection also can promptly reduce unit mass supercritical fluid extraction of tobacco mass of medium flow and realize by changing.For example, the supercritical fluid flow with every kilogram of tobacco is reduced to less than 30kg/h.Compare with the peculiar compound of other tobaccos, each can be implemented separately or implement with various various combinations to each other in the middle of all methods of the removal of summarizing above that makes extraction deflection nitrosamine.

Ion exchange resin in optional additional as on the said method basis, second chamber 2 after the closed-system pressure relief, water flushing or washing.Subsequently, the treatment with ultraviolet light of washings from the ultraviolet source (not shown).Washings cause the degraded of nitrosamine in the washings through UV-irradiation.Subsequently, the extract except that nitrosamine can combine with tobacco again in the washings.Other extract can comprise, for example nicotine and/or fragrance matter.Like this, final result is, nitrosamine is optionally removed from tobacco, and the taste of tobacco does not affect adversely.

Some embodiment of above-described various variation schemes is disclosed in the following table 2.

Consider the changeability of nicotine and content of nitrosamines in every batch of tobacco, from every batch, reserve 300kg as this batch in the same old way.From each of 4 batches of collections in the same old way nicotine and content of nitrosamines are provided in the table below 3.

Table 3

Embodiment 3

Equipment shown in Figure 2 also is closed-system, and this equipment comprises: chamber 1, import 8 and outlet 9 are arranged, and interconnection pipeline 10, wherein pipeline 10 is connected to each other the import 8 of chamber 1 with outlet 9, and fluid delivery system, and promptly pump 4.This equipment also comprises storage tank 5, links to each other with chamber 1 by pipeline 6.Valve 7 is arranged in pipeline 6, and storage tank 5 can be closed.Adjacent with the position of pipeline 10 is ultraviolet source.

In the operation of Fig. 2 equipment, the pipe tobacco of about 100kg moisture content appropriateness is placed in the chamber 1.Fill with carbon dioxide in the storage tank 5, subsequently, this carbon dioxide is pressurizeed by the pump installation (not shown), and is transported to chamber 1 and pipeline 10 by pump installation from storage tank 5, until the extraction conditions that reaches regulation, that is, and the about 250bar of pressure; About 50 ℃ of temperature.Subsequently, storage tank 5 seals by shut off valve 6.Then, therefore supercritical carbon dioxide flows through chamber 1 (and, pass the tobacco of wherein being equipped with) and flows through pipeline 10 and circulates under the effect of pump 4.Supercritical carbon dioxide extraction medium in ultraviolet source 11 irradiation channels 10.Therefore, the nitrosamine in the supercritical carbon dioxide is degraded.Subsequently, its catabolite for example can be removed by making stream of supercritical carbon dioxide cross the wire netting (not shown).Pipeline 10 comprises, at least in ultraviolet light source region 11, but the ultraviolet light permeable material, for example, the high pressure quartz window.The amount of supercritical carbon dioxide in interconnection pipeline 10 maintains extremely low-level owing to adopt the pipeline of little internal diameter (that is about 1cm diameter).After UV-irradiation, supercritical carbon dioxide turns back to chamber 1, and contacts with wherein tobacco once more.The time of supercritical carbon dioxide circulation 30min.Subsequently, chamber 1 and pipeline 10 by opening the emptying device (not shown) pressure relief.The tobacco of so handling does not contain or is substantially free of nitrosamine, and the nicotine content of tobacco but keeps basic identical before and after handling.

Another kind of alternate device (not shown) comprises equipment shown in Figure 2 substantially, and just the fluid in chamber 1 can see through and adorn nitrosamine removal material in the container.This fluid can circulate for several times along whole system, and then removes, and randomly wherein removes the post processing of nitrosamine through associating.

Claims

1. method for treatment of tobacco, wherein the pH value less than 6.5 tobacco through the processing of supercritical fluid extraction medium so that from described tobacco, extract nitrosamine, described tobacco is one or more in pipe tobacco, full wafer leaf tobacco, tobacco end and the reconstituted tobacco, and wherein the mass flowrate of the described supercritical fluid extraction medium of every kilogram of tobacco is 1～55kg/h.

2. the process of claim 1 wherein and remove processing, described nitrosamine is separated from described supercritical fluid extraction medium by described spe medium being carried out nitrosamine.

3. the method for claim 2, wherein said nitrosamine are removed to handle and are comprised the chemisorbed step.

4. the method for claim 3, wherein said chemisorbed step comprises the use of ion-exchanger.

5. the method for claim 2, wherein said nitrosamine are removed to handle and are comprised adsorption step.

6. the method for claim 5, wherein said adsorption step need be selected from one or more the adsorbent in the middle of bead, active carbon, alumina silicate and the zeolite.

7. the method for claim 2, wherein said nitrosamine are removed to handle and are comprised that described spe medium handles with ultraviolet light.

8. the method for claim 2, wherein said nitrosamine is removed to handle and is comprised any in the middle of the following method: be settled out described nitrosamine from described spe medium, described spe medium generation nitrosamine specific enzymes is decomposed, perhaps the described nitrosamine of chromatographic isolation from described spe medium.

9. the method for any one in the claim 2～8, wherein said nitrosamine are removed to handle and are comprised that multiple removal handles.

10. the method for any one in the claim 2～8, after wherein said nitrosamine is removed and is handled, described spe medium does not contain described nitrosamine fully, contacts with tobacco, so that the extract except that nitrosamine can combine or combination again with described tobacco in the described spe medium again.

11. the method for claim 9, after wherein said nitrosamine is removed and is handled, described spe medium does not contain described nitrosamine fully, contacts with tobacco, so that the extract except that nitrosamine can combine or combination again with described tobacco in the described spe medium again.

12. the method for claim 10, wherein said extract comprises nicotine and/or fragrance matter.

13. the process of claim 1 wherein that described supercritical fluid extraction medium is a supercritical carbon dioxide.

14. the process of claim 1 wherein and before described tobacco is with described treatment with supercritical fluid, in described tobacco, add acid; Perhaps before described tobacco is with described treatment with supercritical fluid, in described supercritical fluid, add acid.

15. the method for claim 14 wherein also adds organic solvent except that described acid, perhaps add organic solvent and replace described acid.

16. the method for claim 15, wherein organic solvent is an alcohol.

17. the method for claim 4 wherein adds acid in ion-exchanger.

18. the method for claim 5, wherein said adsorption step comprises the use adsorbent, and wherein adds acid in described adsorbent.

19. the method for claim 17 or 18 wherein also adds organic solvent except that described acid, perhaps add organic solvent and replace described acid.

20. the method for claim 19, wherein organic solvent is an alcohol.

21. the method for claim 14 or 15, wherein said acid is organic acid.

22. the method for claim 17 or 18, wherein said acid is organic acid.

23. the process of claim 1 wherein before described tobacco is with described treatment with supercritical fluid, in described tobacco or before described tobacco is with described treatment with supercritical fluid, in described supercritical fluid, to add and be selected from the sour of malonic acid, ascorbic acid, butanedioic acid, glutaric acid, adipic acid, malic acid, tartaric acid, glactaric acid and citric acid or their salt derivative.

24. the method for claim 23, wherein said salt derivative is a citrate.

25. the method for claim 24, wherein said citrate is a potassium citrate.

26. the method for claim 17 or 18, wherein adding is selected from the acid of malonic acid, ascorbic acid, butanedioic acid, glutaric acid, adipic acid, malic acid, tartaric acid, glactaric acid and citric acid or their salt derivative in ion-exchanger or adsorbent.

27. the method for claim 26, wherein said salt derivative is a citrate.

28. the method for claim 27, wherein said citrate is a potassium citrate.

29. the method for claim 1 comprises the step that improves temperature and pressure, thereby makes described nitrosamine with the described extraction of described supercritical fluid from described tobacco, carries out under the pressure and temperature that improves.

30. the method for claim 29, wherein when supercritical fluid was supercritical carbon dioxide, described pressure was 100～350bar.

31. the method for claim 30, wherein said pressure are 200～300bar.

32. the method for claim 31, wherein said pressure are 240～260bar.

33. each method in the claim 29～32, wherein said temperature is greater than 35 ℃.

34. the method for claim 33, wherein said temperature are 35 ℃～140 ℃.

35. the method for claim 34, wherein said temperature are 35 ℃～90 ℃.

36. the process of claim 1 wherein that but described tobacco is placed in sealing chamber or the pressure pan during it being carried out described extraction processing with supercritical fluid.

37. the method for claim 29, the temperature of wherein said raising is by conducting heat or reaching by electromagnetic radiation.

38. the process of claim 1 wherein does not have or considerably less nicotine is removed from the described tobacco described spe medium.

39. the process of claim 1 wherein that the pH value of described tobacco is less than 5.5.

40. the process of claim 1 wherein that it is 1.1: 1～18: 1 with the ratio that nicotine reduces percentage that nitrosamine reduces percentage.

41. the method for claim 40, wherein said ratio are 1.3: 1～10: 1.

42. the method for claim 41, wherein said ratio are 2: 1～6: 1.

43. the process of claim 1 wherein that described mass flowrate is 10～40kg/h.

44. the method for claim 43, wherein said mass flowrate are 15～35kg/h.

45. the method for claim 44, wherein said mass flowrate are 30kg/h.

46. the process of claim 1 wherein that described tobacco is through the processing of microorganism deactivation.

47. the method for claim 46, wherein said microorganism deactivation are handled and are comprised pasteurized process.

48. the method for claim 47, wherein said tobacco are heated to 70 ℃～150 ℃ temperature and the time that keeps 30s～2min.

49. the method for claim 47, wherein said pasteurized process be Convective Heating, heating using microwave or the radio frequency heating that contacts with the gaseous state heat medium by described tobacco, described tobacco heated realize.

50. each method in the claim 46～49 is wherein carried out the water content of the tobacco of described microorganism deactivation processing and can be regulated by preconditioning or back regulating step.

51. the method for claim 47, wherein said microorganism deactivation is handled the use that comprises ionising radiation, ultra-violet radiation, freeze drying or electron beam.

52. the process of claim 1 wherein before described tobacco is with described treatment with supercritical fluid, during or after, described tobacco is handled through peroxynitrite and/or nitrate removal.

53. the method for claim 52, wherein said nitrite and/or nitrate removal processing comprise with solvent extraction removes nitrite and/or nitrate from described tobacco, carry out ion-exchange subsequently so that with described nitrite and/or the fixing step of nitrate.

54. removing, the method for claim 52, wherein said nitrite handle the use that comprises oxidation step or microorganism.

55. each method in the claim 52～54, wherein this method further comprises ascorbic acid is applied in the described tobacco, the step that combines or combine with chemical adsorption medium with described supercritical fluid.

56. each employed nitrosamine extraction equipment among the claim 1-55, wherein said equipment is closed-system, comprise first chamber of using with the described tobacco of treatment with supercritical fluid, second chamber of carrying out described nitrosamine removal processing, described each chamber is connected to each other by interconnection device, and described equipment comprises that also the supercritical fluid feeding mechanism of supplying supercritical fluid, operation are used for causing fluid delivery system that described supercritical fluid circulates along described closed-system and the nitrosamine that is contained in described second chamber to remove material.

57. the equipment of claim 56, wherein said fluid delivery system is a pump.

58. the equipment of claim 56, wherein said fluid delivery system is a pressure system.

59. each equipment in the claim 56～58 wherein is provided with a plurality of chambers that interconnect, and is used for the described tobacco of treatment with supercritical fluid, and/or is provided with a plurality of chambers that interconnect, and is used for described nitrosamine and removes processing.

60. the equipment of claim 59, wherein said supercritical fluid flows through described chamber successively.

61. the nitrosamine extraction equipment of any one use in the claim 1～55, described equipment is closed-system, and wherein said closed-system comprises having by the inlet device of interconnection device connection and the chamber of outlet device, fluid delivery system and nitrosamine removal device.

62. the equipment of claim 61, wherein said nitrosamine removal device are included in ion-exchanger or the adsorbent in the permeable container of supercritical fluid of being contained in the described chamber.

63. being used for supercritical fluid extraction medium described outlet device from described chamber under the fluid delivery system effect, the equipment of claim 62, wherein said interconnection device removes the conveying for the treatment of apparatus to the described inlet device of described chamber by nitrosamine.

64. one kind by the burley after each method is handled among the claim 1-55, wherein the content of nitrosamines of this burley is lower by 60% than the burley before handling, and the initial content of nitrosamines after the burley slaking before handling is 0.3ppm～30ppm.

65. one kind by the Virginia tobacco after each method is handled among the claim 1-55, wherein the content of nitrosamines of this Virginia tobacco is lower by 60% than the Virginia tobacco before handling, and the initial content of nitrosamines after the Virginia tobacco slaking before handling is less than 8.5ppm.

66. one kind by the burley after each method is handled among the claim 1-55, the content of nitrosamines after wherein this burley is handled is 3.6ppm or littler, and the initial content of nitrosamines after this burley slaking before handling is 5～6ppm.

67. U.S.'s tobacco composition, wherein this mixture each its nitrosamine minimizing percentage of method processing back in by claim 1-55 is 1: 1～10: 1 with the ratio that nicotine reduces percentage, and before wherein each method is processed in pressing claim 1-55, the Ninicotine content of this U.S.'s tobacco composition is 0.10～2.0%, and content of nitrosamines is 0.10～1.2 μ g/g.

68. Virginia tobacco mixture, wherein this mixture each its nitrosamine minimizing percentage of method processing back in by claim 1-55 is 1: 1～10: 1 with the ratio that nicotine reduces percentage, and before wherein each method is processed in pressing claim 1-55, the Ninicotine content of this Virginia tobacco mixture is 0.10～2.0%, and content of nitrosamines is 0.10～1.2 μ g/g.

69. the tobacco composition of claim 67 or 68, wherein said ratio are 5: 1 or bigger.

70. the tobacco composition of claim 67 or 68, wherein said ratio are 8: 1 or bigger.