[Discrimination of Tea Varieties by Using Infrared Spectroscopy with a Novel Generalized Noise Clustering]

The discrimination of tea varieties plays very important role in the production and sale of tea. It is of great significance for the study of a fast, easy and simple method for the identification of tea varieties. The combination of infrared spectroscopy detection technology and fuzzy clustering algorithm is one of the most effective and practical techniques in the detection of tea varieties. To realize the rapid discrimination of tea varieties, a novel generalized noise clustering (NGNC) was proposed based on fast generalized noise clustering (FGNC). Euclidean distance in the objective function of FGNC was replaced with the pth power of Euclidean distance and clustering accuracy was being improved. Emeishan Maofeng; high quality Leshan trimeresurus and low quality Leshan trimeresurus were prepared as the research object and the infrared reflectance (IR) spectra of tea samples were collected with FTIR-7600 infrared spectrometer. Firstly, the high-dimensional IR spectra of tea samples were reduced by principal component analysis (PCA). Secondly, linear discriminant analysis (LDA) was used to extract the discriminant information from the low-dimensional data. Finally, FGNC and NGNC were performed to identify tea varieties. The experimental results showed that in comparision with FGNC, NGNC has higher clustering accuracy, better cluster centers and faster convergence speed. Infrared spectroscopy coupled with NGNC, PCA and LDA could cluster IR spectra of tea samples quickly and correctly, which provided a new method and new idea for identifying tea varieties based on infrared spectroscopy and fuzzy clustering.