The present invention relates to the discovery that specific human taste receptors in the T2R taste receptor family respond to particular bitter compounds present in hydrolyzed soy protein derived materials. The invention further relates to the use of these T2R receptors in assays for identifying ligands that modulate the activation of these taste receptors by specific bitter ligands present in hydrolyzed soy protein materials and derivatives thereof and related compounds. These compounds may be used as additives and/or removed from soy-based foods, beverages, cosmetics and medicinals in order to modify (block) T2R-associated bitter taste elicited by bitter ligands present in hydrolyzed soy protein materials. Also these T2R ligands potentially may be used as therapeutics to treat and modulate hT2R1 or hT2R67 associated gastrointestinal and metabolic functions such as serum cholesterol levels as well as treat gastrointestinal and metabolic diseases such as eating disorders, food sensing, food absorption, obesity, diabetes, Crohn's disease, celiac disease, et al.