Fall is around the corner, and coffee shops everywhere are rolling out their pumpkin spice-flavored warm drinks. The drink feels warm to the touch because of the temperature, but somehow the pumpkin spice flavor also tastes warm. Why do we associate warm or cold temperature with certain foods?
The body senses temperature through proteins on the nerves in the skin and tongue called transient receptor potential (TRP) channels. There are six TRP channels that respond to temperature, and each respond to different temperature ranges: painfully cold (TRPA1), cold (TRPM8), warm (TRPV4 and TRPV3) and painfully hot (TRPV1 and TRPV2).
Besides temperature, these proteins can also be stimulated by chemicals found in food. Chili peppers have capsaicin that stimulates TRPV1, the protein that responds to heat, which is why spicy foods feel hot even if the food itself isn’t piping hot. Mint contains menthol that stimulates TRPM8, the protein that responds to cold, which is why chewing mint gum feels refreshingly cool.
Pumpkin-themed drinks are usually spiced with cinnamon, cloves and nutmeg. These spices stimulate TRPV3, the protein that responds to warmth, making the pumpkin spice latte warm to the touch and taste. While you sip your spicy latte, explore other foods that stimulate TRP proteins in this Scientific American article.