Decoding Bitter Taste Perception in Medicine-Food Homology Substances: A Multimethod Data and Sensory Assessment Approach.

Medicine and Food Homology (MFH) substances are often limited by bitter off-flavors that may limit consumer acceptance. This study employed a multimethod approach integrating electronic nose (E-nose), sensory evaluation, electronic tongue (E-tongue), gas chromatography-ion mobility spectrometry (GC-IMS), and electroencephalography (EEG) to investigate bitterness perception in five representative MFH extracts (Chenpi, Lotus leaf, Sichuan pepper, Gardenia, and American ginseng). Sensory and E-tongue analyses revealed discrepancies between perceived and chemically measured bitterness. GC-IMS identified distinct volatile fingerprints, highlighting differences in aroma composition among samples. EEG results showed that several conventionally bitter extracts were primarily associated with low-frequency scalp-EEG activity (δ-α bands), whereas Sichuan pepper showed an apparent delayed broadband increase extending into the β-γ range. Descriptive scalp EEG patterns varied across MFH stimulation conditions, including differences at frontal and temporal electrodes. Overall, this study provides an exploratory multimethod characterization of the sensory, instrumental, and scalp-EEG responses elicited by different MFH extracts.