Why do sour things make your lips pucker?

Grapefruit


Dill Pickles


Lemons


Orange Juice


LimesWhy do sour things make your lips pucker?
The acid in the food.Why do sour things make your lips pucker?
im guessing by the way:


i think since most things people/you eat has sugar in it which makes you used to sweetness, every once in a while, when you eat something sour your mouth isnt used to it and then your tounge pushes against your lips and puts the sourness on there and then your lips poke out and ppl call that ';pucker'; same thing when your cold. your usually warm b/c of ur ';bodyheat';