A novel double-sampled square-wave voltammetric technique combined with quadruple-disk metallic-glassy carbon electronic tongue for isotonic beverages profiling

This work demonstrates that quadruple-disk electrodes with an innovative design, iridium-platinum, platinum-glassy carbon, and iridium-glassy carbon can effectively function as a single sensor and act as a voltammetric electronic tongue in food profiling. The key strategy used was a novel technique called double-sampled differential square-wave voltammetry (DSSWV), which increased the resolution and enabled extraction of the full, hidden information available in the measuring signals. Four clustering validity indices, namely the Calinski – Harabasz index, Davies – Bouldin index, Silhouette index and gap statistics were employed to select the optimal sensor and methodology for interpreting the current samples. The best expected results were obtained using an iridium-platinum electrode combined with overall cathodic potential modulation using the DSSWV technique. Principal component analysis and polar dendrogram confirmed the correct clustering of different isotonic beverages. However, it was also demonstrated that in some variants of measurement and signal interpretation, it was not possible to group the samples appropriately.