Abstract: Disclosed is a method of producing an expanded tobacco material. According to the method, a tobacco material (TM) is fed into a pressure vessel (11), followed by pressurizing the interior of the pressure vessel (11) with a carbon dioxide gas to a predetermined impregnation pressure. Then, a liquid carbon dioxide (21) is supplied from above the tobacco material (TM) into the pressure vessel through a sintered metal plate (13), etc., while maintaining the impregnation pressure, thereby saturating the interior of the pressure vessel (11) with a carbon dioxide gas generated by vaporization of the supplied liquid carbon dioxide, and cooling the tobacco material by the latent heat of vaporization of the liquid carbon dioxide, so as to impregnate the tobacco material with carbon dioxide. The tobacco material impregnated with carbon dioxide is brought into contact with a hot gaseous stream within a gaseous stream dryer so as to expand the tobacco material.

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.

Abstract: Burley tobacco when cured is sought after as a component of commercial cigarette blends. The inventors have found that, to avoid its less desirable features, one may replace Burley with cured bright tobacco which has been heated in the presence of ammonia at moderate temperature.

Abstract: Cut tobacco is treated with a supersaturated aqueous solution of calcium citrate and excess moisture is removed. The result is a significant increase in the filling power of the cut tobacco.

Abstract: An improved process for increasing the filling capacity of tobacco is provided in which tobacco is contacted with vapors of an expansion agent such as, for example, a low-boiling highly volatile hydrocarbon and/or halocarbon, at elevated temperature and pressure conditions, then releasing the pressure to about atmospheric pressure in a relatively short time period, such as from one second to ten minutes, so that the tobacco is expanded so as to increase its filling capacity in the absence of a subsequent heating step.