Not much is known about the Capsian receptor not being all that important in clinical medicine or biology, but it is a pain receptor what is activated by thermo-neuclear heat which Capsian binds to.
There are no reports that I could find of over-depolarization of these receptors in medical literature, so it is most likely that your problem is due to trauma in the CNS, such as a microlesion on the area of the brain that processes taste.
(Edited 41 seconds later.)