Relationship between overall difference decision and electronic tongue: Discrimination of civet coffee

• Electronic tongue can be used to discriminate civet coffees from normal coffees.
• Consumers are able detect the differences of civet coffees from normal coffees.
• The countries and location affect consumer ability to distinguishing civet coffees.
• There is a correlation between electronic tongue and consumers' perception.

This paper demonstrates a new approach to relate electronic tongue (E-tongue) to human perception for fine quality of beverage. Six civet, one weasel and one non-civet coffees were chosen as the testing platform. The sensory test based on the overall difference method by pair comparison followed by sureness-rating tasks was divided into three experiments. In each, 12–14 consumers were asked to express differences in six pairs of hot brew coffee samples on a four-point scale. The results were analyzed by the Multi-Dimensional Scaling (MDS) analysis. An in-house electronic tongue based on cyclic voltammetry and the Principal Component Analysis (PCA) was applied to measure the coffee samples, alongside the panel test. The relationship between PCA and MDS solutions was obtained by Generalized Procrustes Analysis (GPA), which reveals a strong correlation between E-tongue and human perception. Both were able to identify differences between all coffee samples from different sources.