LAUSR

Abstract The potential of cyclic voltammetry electronic tongue (CVET) coupled to chemometrics was investigated for measuring total free amino acids (FAA) content in black tea. Two working electrodes - glassy carbon electrode and platinum electrode were comparative and syncretic in prediction of total FAA content. Synergy interval partial least square (Si-PLS) combined with variable combination population analysis (VCPA), namely Si-VCPA-PLS, was creatively employed for searching characteristic variables selection from the whole cyclic voltammetry data set. Cyclic voltammetry signals coupled Si-VCPA-PLS model results represented its feasibility in estimating total FAA content in black tea, achieved with Rp = 0.8185 for the glassy carbon electrode; Rp = 0.8366 for the platinum electrode; and Rp = 0.8414 for their data fusion. The extracted characteristic variables were only occupying about 0.2% of the origin. This work confirmed that the cyclic voltammetry electronic tongue could be as a fast, low-cost, efficient and complementary approach for predicting total FAA content in black tea.