Tastes Produced by Peptides Containing Ionic Groups and by Related Compounds

The typical tastes imparted by ionic groups are salty-like of sodium chloride and umami-like of monosodium glutamate, but the relationship between the taste and chemical structure has not previously been elucidated. One of the reason for the difficulty in understanding the taste-structure relationship is the presence of the ambiguous and unfavorable tastes of neutral salts. We define the strange tastes of neutral salts (TNS) collectively in a specific category, and then the tastes due to ionic groups. Sour, salty, and umami tastes and TNS were studied for different acidic and basic groups and various combinations of both groups to elucidate the taste characteristics of the ionic groups. The results reveal that the tastes due to ionic groups have common characteristics, being different from bitter and sweet tastes.