why peppers taste hot. The heat sensation is caused by capsaicin, which is a colorless, odorless, oily chemical found in peppers. Capsaicin binds with certain sensory neurons which then more or less trick your body into thinking that it is being burned or at least experiencing excessive amounts of heat in the area that the capsaicin comes in contact with, even though no actual physical burning is taking place. Specifically, what is going on is that the capsaicin is binding to the vanilloid receptor (VR1), which is a member of the superfamily TRP ion channel and thus is referred to as TRPV1; by binding to the VR1 receptor, the capsaicin molecule will produce the same sensation, or signal to the brain, that normal heat will produce when activating the TRP receptors. This is why eating peppers makes your mouth feel really hot, even though it’s not.