Aroma Characteristics of Stored Tobacco Cut Leaves Analyzed by a High Vacuum Distillation and Canister System

Abstract

An extraction method using a high vacuum distillation extraction apparatus coupled to a canister was newly developed for the analysis and sensory test of tobacco leaf volatiles. We extended the application of the canister that is used in environmental analysis, to the extraction of the aroma components in tobacco leaves. The volatile components with vapor pressures higher than 0.1 mmHg were easily evaporated under decompression and then trapped into the vacuumed canister. After the collection of volatiles, the canister was pressurized by a slow stream of inert gas in order to emit the whole aroma under a controlled flow. Applying a preconcentrator--gas chromatography/mass spectrometry (GC/MS) and sensory test to the headspace gas components, the aroma alteration between 0 and 2 weeks of storage was simultaneously or individually evaluated. As a result, after the storage, alcohols such as 1-hexanol, linalool, and benzyl alcohol decreased significantly. The amount of carotenoid derivatives that have the characteristic tobacco leaf aroma had not changed. Sensory evaluation of the same headspace gas with that used for GC/MS demonstrated the alternation of the aroma quality before and after storage. The main changes were the decrease of greenness and smoothness in aroma and the decrease of ethylbenzene, 2-pentylfuran, 1-hexanol, benzaldehyde, and linalool concentrations.