Headspace Volumetric Karl Fischer Titration for the Determination of Water Content in Finished Tobacco Products

Because many physicochemical properties of tobacco are highly sensitive to its moisture content, the determination of water level is an important parameter for tobacco characterization. A headspace volumetric Karl Fischer titration (HS-V-KFT) method is presented for the quantification of water content in different finished tobacco materials. The parameters affecting the extraction of water from the tobacco materials were the sample size and the oven temperature which have been optimized. The extraction of water from the samples was achieved within a reasonable time (<25 min) with a sample size of 200 mg and an optimum temperature of between 90 °C and 100 °C. The results of the water determination by HS-V-KFT at the optimized parameters were in good agreement with those obtained by standard volumetric Karl Fischer titration. HS-V-KFT showed very good repeatability (RSDr 0.9%) and intermediate precision (RSDiR 1.1%). With respect to a considerable time saving, solvent consumption reduction, precision and accuracy, HS-V-KFT can therefore be suggested as the method of choice to determine water amount in finished tobacco products.