US 5,590,667 A · Tobacco expansion method

Abstract

A tobacco expansion method is provided whereby cured tobacco is first moistened with a humectant solution, as is conventional in the industry, to increase the resident liquids thereof. Next, the prepared tobacco in shredded form is placed in a sealed chamber and the chamber evacuated to vaporize a portion of the resident liquids. Next, ethyl alcohol vapor is allowed to enter the pressure chamber below 70 mm (Hg) absolute to prevent a water-ethyl alcohol azeotrope from forming. Thereafter, a hydrocarbon vapor, such as n-pentane vapor, is directed into the chamber and the pressure restored to atmospheric. The n-pentane vapor diffuses into the cellular structure of the tobacco with the assistance of the ethyl alcohol, whereafter the tobacco is heated and the n-pentane and ethyl alcohol acts as a propellant to expand the tobacco.

Claims17

Dependent claims

A method of expanding tobacco comprising the steps of:

(a) placing tobacco having a plurality of resident liquids in a vacuum chamber;
(b) depressurizing the chamber to effect vaporization of said resident liquids;
(c) partially repressurizing the chamber with ethyl alcohol vapor while maintaining a low chamber pressure to prevent a water-alcohol alcohol azeotrope from forming;
(d) further repressurizing the chamber with a hydrocarbon vapor until atmospheric pressure is achieved;
(e) maintaining atmospheric pressure in the chamber to allow diffusion of the hydrocarbon into the tobacco, and
(f) thereafter heating the tobacco to expand the same.

3 more elements

Dependencies are inferred from the claim text.

Tobacco expansion method

Life of this patent

Tobacco expansion method

Life of this patent

Abstract

Claims17