Evaluation of Chinese tea by the electronic tongue: Correlation with sensory properties and classification according to geographical origin and grade level

Research was conducted to compare tea quality measured by a trained sensory panel and instrument analysis using a potentiometric sensor array. This array is formed by a set of non-specific all-solid-state potentiometric sensors and has been used in combination with principal component analysis (PCA) for the classification of tea samples from different geographical origins and quality grades. The method used to assess 10 sensory attributes in tea taste such as heavy flavor, thick flavor, sweet flavor, fresh flavor, mellow flavor, astringency, tenderness, stale flavor, purity and fired flavor were in accordance to the China National Institute of Standardization (CNIS) sensory profile test. The relationship between instrumental and sensory measurements of tea was also investigated. Results from these analyses demonstrate that the electronic tongue can be used to predict sensory characteristics and their relationship to the taste quality of tea measured by professional taster.