Evaluation of the taste of crude drug and Kampo formula by a taste-sensing system (4): taste of Processed Aconite Root.

It is difficult to describe the taste of Processed Aconite Root (PAR) because it contains toxic compounds, and tasting poses some risk to the examiner. Therefore, there is no description of the taste of PAR in the latest Japanese Pharmacopoeia, although the taste of crude drugs has been regulated as a criterion for judgment. In this study, we revealed the objective taste of PAR by using a taste-sensing system. The PAR samples examined were classified into four types by how the samples were processed: PAR1 processed by autoclaving; PAR2-a processed by autoclaving after rinsing in salt (sodium chloride) solution; PAR2-h processed by heating after rinsing in calcium chloride solution; PAR3 processed by treating with hydrated lime after rinsing in salt solution. The most characteristic taste factor of PAR is an aftertaste of cationic bitterness, which was detected in all PAR sample solutions, even at the concentration of 0.1 mg/ml. In addition, anionic bitterness and saltiness were detected in all sample solutions at 1 mg/ml. Furthermore, umami was detected in the PAR1, PAR2-a, and PAR3 sample solutions at 1 mg/ml. Detailing the analyses of the four taste factors on the four sample types, we found each type has its own characteristic taste pattern. On the basis of these results, we proposed a method for discriminating one PAR type from another by using the system.