Why do chili peppers burn when they aren’t hot?

A jalapeño straight from the fridge is about 41 °F, yet it burns like a hot stove. Nothing in your mouth actually got warmer. The pepper simply unlocks a sensor on your nerves that normally warns you about heat above roughly 109 °F, and birds can eat the hottest peppers and feel nothing at all. We follow capsaicin from molecule to brain: why spiciness isn’t a taste, how capsaicin slips into the TRPV1 channel like a key in a lock, how that sensor was found using chili pepper itself and won a Nobel Prize, where the heat hides inside the pod, how Scoville heat units are measured, why milk works better than water, why birds don’t feel the burn, how black pepper, wasabi and mint fool other sensors, and when spicy turns dangerous. This is a science explainer, not medical advice. Heat values and study results are rounded; illustrations are simplified. What everyday mystery should we explain next? Subscribe for more science. #Exploriny #ChiliPeppers #Science