Processes for producing flavor substances from tobacco and smoking articles made therewith

摘要

Processes for producing flavor substances from tobacco are disclosed. The processes involve heating tobacco during a first staged heating to a first toasting temperature to drive off volatile materials; increasing the toasting temperature during a second staged heating to a second toasting temperature and separately collecting, as flavor substances, at least portions of the volatile materials driven off at the first and second toasting temperatures. Another aspect of the present invention involves reducing the moisture content of the tobacco without removing volatile flavor components, such as by freeze drying the tobacco, and then heating the dried tobacco. Preferably the tobacco is heated in a flowing gas stream and at least portions of the volatile materials are separately collected as flavor substances as the gas stream passes sequentially through a moderate temperature trap, a cold temperature trap and a filter capable of collecting submicron sized particles. It has been discovered that better flavor release can be obtained from smoking articles that incorporate extracted tobacco flavor substances applied to a substrate if the substances are separately extracted and are then applied separately to a plurality of individual segments of the substrate. Thus one aspect of the present invention is a smoking article comprising separately extracted tobacco flavor substances applied to a plurality of individual segments of a carrier within the smoking article.