The present invention relates to the discovery of a specific human taste receptor in the T2R taste receptor family, hT2R63 that responds to particular bitter compounds The present invention further relates to the use of this receptor in assays for identifying ligands that modulate the activation of this taste receptor. These compounds may be used as additives and/or removed from foods, beverages and medicinals in order to modify (block) T2R-associated bitter taste. A preferred embodiment is the use of the identified compounds as additives in foods, beverages and medicinals for blocking bitter taste.