Tobacco Treatment

Abstract

This invention provides a method for removing undesirable constituents from tobacco which includes extracting tobacco material in an aqueous or organic solvent and filtering the product of the extraction using a horizontal belt filter. The extract and insoluble tobacco residue may be further treated enzymically, chemically or otherwise to remove a complement of undesirable constituents. The extract and insoluble tobacco residue are recombined to form a regenerated tobacco material that is less harmful when combusted than the original material.

1 . A process for the treatment of tobacco using a horizontal belt filter. 
     
     
         2 . A process as claimed in  claim 1 , comprising extracting tobacco with an aqueous or organic solvent and filtering the product of the extraction. 
     
     
         3 . A process as claimed in  claim 2 , wherein both the extracting and filtering steps are performed on a horizontal belt filter. 
     
     
         4 . A process as claimed in  claim 3 , wherein tobacco to be extracted is continuously fed onto the horizontal belt filter and the extracting and filtering steps are performed continuously as tobacco is conveyed along the filter. 
     
     
         5 . A process as claimed in  claim 4 , wherein the filtrate is recycled and used as a solvent in the extraction of tobacco being fed onto the horizontal belt filter. 
     
     
         6 . A process as claimed in any of  claims 1 - 5 , further comprising treating the tobacco with an enzyme. 
     
     
         7 . A process as claimed in  claim 6 , wherein the enzyme is a proteolytic enzyme. 
     
     
         8 . A process as claimed in  claim 6  or  7 , further comprising rinsing the enzyme-treated tobacco with a salt solution. 
     
     
         9 . A process as claimed in  claim 8 , wherein the salt rinsing step is performed on a horizontal belt filter. 
     
     
         10 . A process as claimed in  claim 8 , wherein the enzyme-treated tobacco is rinsed twice with a salt solution. 
     
     
         11 . A process as claimed in  claim 10 , wherein the two salt rinsing steps are performed on separate horizontal belt filters. 
     
     
         12 . A process as claimed in  claim 9  or  11 , wherein salt rinsing is performed continuously as tobacco is conveyed along the filter(s). 
     
     
         13 . A process as claimed in  claim 12 , wherein the filtrate from the second salt rinsing is recycled and used as a salt solution in a first salt rinsing of tobacco being fed onto the first salt rinsing horizontal belt filter. 
     
     
         14 . A process as claimed in any of  claims 6 - 13 , further comprising deactivating the enzyme in the tobacco. 
     
     
         15 . A process as claimed in  claim 14 , wherein deactivation is carried out by steam treating, heat treating or chemically treating the tobacco. 
     
     
         16 . A process as claimed in  claim 15 , wherein deactivation is performed on tobacco on a horizontal belt filter. 
     
     
         17 . A process as claimed in any of  claims 1 - 16 , performed using multiple horizontal belt filters in series. 
     
     
         18 . A process as claimed in  claim 1 , comprising:
 (a) extracting tobacco with an aqueous or organic solvent;   (b) treating the tobacco with an enzyme;   (c) rinsing the enzyme-treated tobacco with a salt solution; and   (d) deactivating the enzyme in the tobacco;   
       wherein one or more of steps (a) to (d) are performed on a horizontal belt filter. 
     
     
         19 . A process as claimed in any of  claims 2 - 18 , further comprising treating the tobacco extract obtained from the extraction of tobacco to remove protein therefrom. 
     
     
         20 . A process as claimed in  claim 19 , wherein the tobacco extract is treated with bentonite. 
     
     
         21 . A process as claimed in any of  claims 2 - 20 , further comprising treating the tobacco extract obtained from the extraction of tobacco to remove polyphenols therefrom. 
     
     
         22 . A process as claimed in  claim 21 , wherein the tobacco extract is treated with polyvinylpolypyrrolidone (PVPP). 
     
     
         23 . A process as claimed in any of  claims 19 - 22 , further comprising the recombination of the extracted tobacco and treated tobacco extract. 
     
     
         24 . Tobacco obtainable by a process as claimed in any of  claims 1 - 23 . 
     
     
         25 . A smoking article comprising tobacco as claimed in  claim 24 .