In Chinese medicine, each of the five “solid” organs corresponds with a flavor. The spicy taste corresponds with the lungs, sweet with the spleen/pancreas, salty with the kidneys, sour with the liver and bitter with the heart. Some of these correspondences are logical - regulation of glucose by the pancreas suggests a correspondence to sweetness, and the kidneys' regulation of water could easily correspond to the salty taste. The idea that bitterness corresponds to the heart, though, is a less straight-forward and even somewhat dramatic concept. Now, researchers have made a surprising finding that there are actually taste receptors, formerly thought to exist primarily in the mouth, on the heart. And, lo and behold, the receptors that exist on the heart pick up the bitter taste, specifically. In fact, according to the research, almost half of the receptors for the bitter taste are located on the heart.