Why do lemons taste sour?
Lemon Alarm System
Why do lemons taste sour?
You bite into a lemon and — wow! — your whole face scrunches up. Your mouth puckers, your eyes squeeze shut, and you feel like your tongue just got ambushed. What is happening in there?
Inside that yellow fruit, tiny molecules called citric acid are flooding your mouth. Acid is a special kind of chemical that acts like an overeager messenger — it really, really wants to share its hydrogen atoms with anything nearby.
