Impedimetric multi-sensor system with gold and silver nanoparticles applied for basic taste assessment compared with human threshold method sensory analysis.

Threshold determination forms an integral part of sensory and consumer studies applied for product control and development. The authors examined the potential of an impedimetric electronic tongue to discriminate basic tastes and consider limitations pertaining to the sensory evaluation process. Three samples at lower, medium, and higher concentration levels of basic taste compounds were prepared and subjected to consumer studies (n = 60) using the difference from-control (DFC) test. Simultaneously, all basic tastes were subjected to electronic tongue measurements. The incorporation of nanoparticles increased the overall sensitivity of the electrodes that were examined using the PCA biplot. Results confirmed the efficiency of an electronic tongue in classifying basic tastes, with higher prediction sensitivity of about 99-100 % in non-electrolytic rich compounds such as caffeine, tannic acid, and sucrose. The values dipped among electrolytic compounds such as sodium chloride, monosodium glutamate, and citric acid, which require further investigation. In conclusion, the increased sensitivity to non-electrolytes supports the versatility and economical importance an impedimetric electronic tongue can present for food and pharmaceutical applications.