Why does spicy food taste ‘hot’, and minty food taste ‘cold’? Why do we interpret these tastes as specifically ‘hot’ and ‘cold’ respectively? My mouth does not actually rise in temperatire if I eat spicy kim chee, nor does it drop in temperature if I suck on a breath mint…
Your taste receptors are being tricked by the chemicals in the food into somewhat the same sensation as hot and cold.
The capascian (spelling butchered)…the “hot” stuff that makes chile peppers hot… has a way of stimulating the pain receptors in your mouth just like hot foods do. I believe menthol and mint work in a similar, but opposite way on the pain receptors.
Hot and Cold food like chiles and mints have chemicals that work on the pain receptors.
There is a certain truth at least to the “hot” side. Capsaicin acts as an irritant bringing blood to the area.
I think the “mint/cold” thing has to do with evaporation on the surface of the tongue. You only get the “cold” sensation when you breathe over your tongue; it may be that the mint allows water to evaporate more quickly, which I believe would cause a “cold” sensation. Alcohol-based gels, such as are used to sterylize the skin before performing an injection, do the same thing. Blow on the skin, and it’ll definitely feel cold, due to evaporation.
Geez; Philster had it almost right; the rest of these guesses are way off.
Capsaicin, menthol, and the like do indeed act directly on nerve receptors.
Specifically, capsaicin directly stimulates heat receptors in the pain pathway.
http://www.academicpress.com/inscight/10221997/graphb.htm
Capsaicin certainly is a rubefacient and irritant, but these do not directly address its “heat.”
Similarly, menthol (and, I think, methyl salicylate) directly stimulates a newly-discovered receptor for cold. Evaporative cooling may certainly add to the sensation, but it has nothing to do with how menthol actually works.
Sorry, forgot a link: http://www.nature.com/nature/links/020307/020307-1.html
I love the SDMB! 
I guessed that something like this might be working, but it’s nice to know.