acids trigger this taste

A) sweetness
B) sourness
C) fattiness
D) umami
E) bitterness

Acids

Substances with a pH less than 7 that are capable of donating a proton (H+) to another compound (a base), characterized by a sour taste.

Sourness

Sourness is one of the five basic tastes and is caused by acids in food.

Sweetness

A taste sensation often caused by sugar or substances with a similar chemical structure.