Bitter taste perception plays a particularly vital role when assessing qualitative properties of food. When differentiating between the acceptable flavour composition and the excessively bitter and potentially toxic one, a consumer focuses exclusively on the intensity (volume) of bitter taste perception. The volume diversity of bitter taste stimuli can be assessed by analyzing the reproducibility of structural properties in a set of bitter ligands. An effective research method to investigate the intensity of bitter taste perception are 3D pharmacophore models. A simple pharmacophore model (SPM that stands for Simple Pharmacophore Model) was used to analyze taste interactions of a series of small molecule ligands from a group of quinolizidine alkaloids. The SPM model made it possible to distinguish two basic affinity domains of the alkaloids being studied: aromatic/hydrophobic (AR/H) and acceptor (HBA₁). Moreover, there was identified a region of N₁₂ nitrogen atom being fundamental for the intensity of bitter taste and exhibiting donor (HBD), acceptor (HBA), and positive ionization (PI) properties. The predicted intensity of bitter taste of quinolizidine alkaloids was described by two molecular descriptors, such as a number of regions stimulating the receptor (NPI that stands for the number of point interactions) and a number of alignments of a single ligand into a hypothetical receptor area (NIS that stands for the number of interactive stimulations). The assigned descriptors (NPI and NIS) were used to formulate a taste equation representing qualitative changes in the predicted intensity of bitter taste (IBT_p) for the group of alkaloids analyzed. The predicted IBT_p values were confirmed by sensory values of the intensity of bitter taste (IBT_s).