Studies on flavored peptides. VIII. Mechanism for the bitter tasting potency of peptides using O-aminoacyl sugars as model compounds.

In order to study the role of hydrophobicity in bitter peptides, several O-aminoacyl sugars, in which amino acids or peptides were attached to the 2- and 3-position of methyl α-D-glucopyranoside, were synthesized and sensory analyses were carried out. It was found that the bitterness increased as the hydrophobicity of compounds increased, implying that the bitterness receptor recognizes the hydrophobicity of bitter peptides. A structure for the bitterness receptor is also discussed.