Reconstituted tobacco and preparation method thereof

Abstract

The present invention provides reconstituted tobacco and a preparation method thereof, and belongs to the technical field of tobacco. The preparation method provided by the present invention includes the steps of: subjecting tobacco stems to hot-water extraction and pulping by mill successively to obtain tobacco stem pulp; mixing the tobacco stem pulp with alkaline matter for oxygen delignification in an oxygen environment to obtain oxygen-delignified tobacco stem pulp, where the alkaline matter includes one or more of sodium hydroxide, potassium hydroxide, potassium carbonate, sodium carbonate and sodium bicarbonate; mixing the oxygen-delignified tobacco stem pulp with tobacco pulp, calcium carbonate and a retention agent, and subjecting the mixture to a papermaking process in the paper machine to obtain reconstituted tobacco sheets; and coating the reconstituted tobacco sheets with a concentrated tobacco extracting solution to obtain reconstituted tobacco. By means of the oxygen delignification of the tobacco stem pulp in the present invention, the lignin component in tobacco stems is partially removed, and the reconstituted tobacco prepared from processed tobacco stems and other raw materials has a soft flavor without wood smell.

What is claimed is: 
     
         1 . A method for preparing reconstituted tobacco, comprising the following steps:
 1) subjecting tobacco stems to hot-water extraction and pulping by mill successively to obtain tobacco stem pulp;   2) mixing the tobacco stem pulp obtained in step 1) with alkaline matter for oxygen delignification in an oxygen environment to obtain oxygen-delignified tobacco stem pulp, wherein the alkaline matter comprises one or more of sodium hydroxide, potassium hydroxide, potassium carbonate, sodium carbonate and sodium bicarbonate;   3) mixing the oxygen-delignified tobacco stem pulp obtained in step 2) with tobacco pulp, wood pulp fibers, calcium carbonate and a retention agent resulting in a mixture, and subjecting the mixture to a papermaking process in a paper machine to obtain reconstituted tobacco sheets; and   4) coating the reconstituted tobacco sheets obtained in step 3) with a concentrated tobacco extracting solution to obtain reconstituted tobacco.   
     
     
         2 . The preparation method according to  claim 1 , wherein the hot-water extraction in step 1) is carried out at a temperature of 40-70° C. and for a duration of 30-120 min. 
     
     
         3 . The preparation method according to  claim 1 , wherein in step 1), the tobacco stem pulp has a moisture content of 10-30 wt %. 
     
     
         4 . The preparation method according to  claim 1 , wherein for the oxygen delignification in step 2) is carried out at a temperature of 90-120° C., for a duration of 5-30 min and a pressure of 0.4-0.8 MPa. 
     
     
         5 . The preparation method according to  claim 1 , wherein the alkaline matter in step 2) has a mass that is 2-20% of that of the tobacco stems in step 1). 
     
     
         6 . The preparation method according to  claim 1 , wherein in step 2), the oxygen-delignified tobacco stem pulp has a concentration of 10-25 wt %. 
     
     
         7 . The preparation method according to  claim 1 , wherein in step 3), the tobacco pulp has a concentration of 5-15 wt %. 
     
     
         8 . The preparation method according to  claim 1 , wherein in step 3), a mass ratio of 1:1 exists between the oxygen-delignified tobacco stem pulp and the tobacco pulp; and the usage of wood pulp fibers, calcium carbonate and the retention agent is respectively 16-25%, 10-20% and 0.1-0.3% of the total mass of the oxygen-delignified tobacco stem pulp and the tobacco pulp. 
     
     
         9 . The preparation method according to  claim 1 , wherein in step 4), the concentrated tobacco extracting solution has a concentration of 35-50 wt %. 
     
     
         10 . The reconstituted tobacco obtained by the preparation method described in  claim 1 . 
     
     
         11 . The reconstituted tobacco obtained by the preparation method described in  claim 2 . 
     
     
         12 . The reconstituted tobacco obtained by the preparation method described in  claim 3 . 
     
     
         13 . The reconstituted tobacco obtained by the preparation method described in  claim 4 . 
     
     
         14 . The reconstituted tobacco obtained by the preparation method described in  claim 5 . 
     
     
         15 . The reconstituted tobacco obtained by the preparation method described in  claim 6 . 
     
     
         16 . The reconstituted tobacco obtained by the preparation method described in  claim 7 . 
     
     
         17 . The reconstituted tobacco obtained by the preparation method described in  claim 8 . 
     
     
         18 . The reconstituted tobacco obtained by the preparation method described in  claim 9 .