The Economist has a very entertaining article about the growing global popularity of chilies. I thought this fact was particularly interesting:
From this point of view, the most interesting trend is not in ever-higher doses of capsaicin [the active ingredient in hot chilies] for the maniac market, but in the presence of chili in a range of foodstuffs that previous generations would have regarded as preposterous candidates for hotting up. Chili-flavoured chocolate, for example, has gone from being a novelty item to a popular mainstream product. Mr Waters sells “hot apple chili jelly” as a condiment for meat, and chili-infused olive oil.
The reason may be that capsaicin excites the trigeminal nerve, increasing the body’s receptiveness to the flavour of other foods. That is not just good news for gourmets. It is a useful feature in poor countries where the diet might otherwise be unbearably bland and stodgy. In a study in 1992 by the CSIRO’s Sensory Research Centre, scientists looked at the effect of capsaicin on the response to solutions containing either sugar or salt. The sample was 35 people who all ate spicy food regularly but not exclusively. Even a small quantity of capsaicin increased the perceived intensity of the solutions ingested.
In school, I was taught that spicy food was invented as a form of food preservation: spices would drown out the taste of rotten food, or so the story went. Apparently, the truth is just the opposite; capsaicin actually increases the flavor of other foods.