It is amazing how much thought and science goes into producing food substances that we take for granted. The real wasabi owes its fiery nature to a volatile chemical called allyl isothiocyanate that binds to specific receptor in humans called TRPA1 – (Transient receptor potential) that is activated by heat in some instances. This allyl isothiocyanate is generated only transiently by the enzyme myrosinase acting on thioglucosides that are released when the cells of the plant rhizome is broken. This preparation of the plant may be critical since it is released only when the plant rhizome is ground up very finely. The allyl isothiocyanate lasts only transiently since the volatile component is lost very rapidly and is almost completely gone in 15 minutes. However, commercial wasabi may be prepared by other horse radish’s that are probably more long lasting.
Interestingly, the same receptor that we use to sense wasabi is the same receptor that is used in snakes to sense heat. In pit-vipers the receptor is so sensitive that it can be used to measure the change in temperature of less that 0.009 C and may be like infrared vision in snakes allowing them to find their prey. This was discovered only recently in a publication in NATURE.
