Bitterness is one of the five recognized basic tastes. Although many groups have examined bitter taste through human sensory evaluation, there are few cases in which its taste quality and temporal characteristics have been comprehensively evaluated. In this study, we conducted sensory evaluations to assess the qualitative and temporal characteristics of bitterness and, through comprehensive analysis, to achieve a more detailed discrimination of the samples. As samples, we used bitter ingredients that are approved for food use in Japan but whose bitterness qualities have remained largely uncharacterized, and we sought to clarify their properties. Results demonstrated that it was possible for panelists to distinguish the nine bittering agents via their taste qualities, evaluated by descriptive analysis and time intensity scaling, providing evidence of differing subqualities of bitter taste. PRACTICAL APPLICATIONS: Humans detect bitterness through a family of 26 taste receptors. These receptors may be sensitive to a family of differing stimuli, with overlap between receptive ranges. This study attempts to answer whether humans can distinguish between different bitter stimuli, or each stimulus is perceived similarly, through the creation of a systematic method to evaluate bitterness.
Watanabe et al. (Wed,) studied this question.