Review of electronic-nose technologies and application for Chinese liquor identification

Due to their sensitivity to a wide diversity of volatile gases, electronic noses are ideal instruments for measuring and monitoring odors and they are being applied in agricultural production testing, biological medicine detection, environmental monitoring, and food testing. An electronic nose (E-nose) utilizes a sensor array to provide a fingerprint response to a given odor, using pattern recognition software to identify and discriminate between odors. Each sensor in the array behaves like a receptor by responding to different odors to varying degrees. The changes are then transduced into electrical signals, which are preprocessed and conditioned before identification by a pattern recognition system. In this paper, recent electronic-nose systems and algorithms are reviewed which developed over the past two decades that have potential applications for detecting Chinese liquors, including brand identification, flavor detection, and the prediction of the ages. In addition, the technical design scheme and the application were detailed for the polymer quartz piezoelectric sensor E-nose.