David,

> on our responses to particular foods? Wow, I am confused!

The instinct has evolved during the whole evolution of live.
During all this time it only had to do with certain products
that we call 'natural' or 'not-denaturated'. So it only
knows how to handle these natural products. Denaturated
products will most often irritate it.

Cooked, seasoned food will most often be very attractive
to men and all other animals. So we have to use our intellect
to exclude unnatural food from our palette.

-Karl