Why does some sour stuff make peoples tongues bleed?

This happens to me if I eat that toxic waste candy, even if it isn't jagged. Why does it do that?

This page is a permanent link to the reply below and its nested replies. See all post replies »

The main ingredient used to make things sour is a substance called malic acid. While it's safe to eat, large quantities of it can cause minor damage to skin and flesh, especially sensitive or thin skin like that found on the tongue.