[Discrimination of traditional Chinese medicinal materials with different tastes based on electronic tongue]

To investigate the use of the electronic tongue in the evaluation of traditional Chinese medicinal materials with sour, bitter, sweet or salty tastes, and assess the possible application of the sensor in the evaluation of different tastes of traditional Chinese medicinal materials.

Aqueous extracts of 22 traditional Chinese medicinal materials were measured by the electronic tongue. The data collected with the tongue was evaluated for discrimination of the samples with multivariate statistical methods: principal component analysis (PCA) and discriminant factor analysis (DFA).

The electronic tongue was capable of discriminating between samples with different taste modalities and could also distinguish different samples eliciting the same basic taste. Twenty-two traditional Chinese medicinal materials could be classified into five clusters based on PCA. These differences seem to derive from the different tastes. DFA was applied to construct a model to discriminate traditional Chinese medicinal materials with different tastes. And the samples yielded about 88.2% accuracy for cross-validation.

We confirmed that the electronic tongue may provide an analytical procedure for classification of the samples with respect to tastes of the traditional Chinese medicinal materials.