Abstract: Tobacco which has been increased in filling power by a conventional tobacco expansion process can be further increased in filling power by a post expansion heat treatment. The post expansion heat treatment comprises contacting the expanded tobacco produced by a conventional expansion process with a gaseous medium, such as air and/or steam, at a temperature of from about 200.degree. F. to about 450.degree. F. The post expansion heat treatment is preferably conducted at a lower temperature than the temperature of the heating step of the expansion process, and thus can be more easily controlled, while providing an additional increase in filling power. The product of the post expansion heat treatment process of this invention has been found to be as acceptable in subjective smoking characteristics as the expanded tobacco which is treated by the process.

Abstract: Impregnated tobacco is expanded in an expansion operation involving the entrainment of the impregnated tobacco in a heated gas stream under high temperature-short entrainment time conditions resulting in a product of improved quality and enhanced expansion.

Abstract: This invention relates broadly to an improved process for expanding tobacco and involves certain modifications of the basic process for expanding tobacco comprising the steps of (1) contacting the tobacco with liquid carbon dioxide to impregnate the tobacco with the liquid carbon dioxide, (2) subjecting the liquid carbon dioxide-impregnated tobacco to conditions such that the liquid carbon dioxide is converted to solid carbon dioxide and (3) thereafter subjecting the solid carbon dioxide-containing tobacco to conditions whereby the solid carbon dioxide is vaporized to cause expansion of the tobacco. The present invention pertains, in one embodiment, to an improvement in the basic process which involves controlling the moisture content of the tobacco which is employed in the first step of the basic process.

Abstract: This invention relates broadly to an improved process for expanding tobacco and involves certain modifications of the basic process for expanding tobacco comprising the steps of (1) contacting the tobacco with liquid carbon dioxide to impregnate the tobacco with the liquid carbon dioxide, (2) subjecting the liquid carbon dioxide-impregnated tobacco to conditions such that the liquid carbon dioxide is converted to solid carbon dioxide and (3) thereafter subjecting the solid carbon dioxide-containing tobacco to conditions whereby the solid carbon dioxide is vaporized to cause expansion of the tobacco. The present invention pertains, in one embodiment, to an improvement in the basic process which involves controlling the moisture content of the tobacco which is employed in the first step of the basic process.