A Quartz Crystal Microbalance Sensor for Detection of Geraniol in Black Tea

Geraniol is one of the important qualities determining volatile components of black tea. This paper presents a quartz crystal microbalance sensor to detect geraniol from black tea aroma. The sensor is developed using β-cyclodextrin (β-CD). β-CD is a flavor encapsulating material with toroidal bucket-like structure, whose inside-cavity is hydrophobic and the outside is hydrophilic and it is found to be a suitable coating material for detecting geraniol. Extensive experiments have been carried out with the β-CD sensor and it is observed that the sensor offers better sensitivity for geraniol in comparison with other important constituents of black tea such as linalool, linalool oxide, methyl salicylate, and trans-2-hexenal. Experiments with ten Darjeeling orthodox black tea samples have been carried out with the developed sensor and a correlation factor of 0.9925 has been obtained with the corresponding gas chromatography mass spectrometry analysis.