Leave a bad/nasty taste in the mouth
Definition 1 of 1
Pro Tip 1/3Negative Connotations
The phrase suggests lingering feelings of discomfort or dissatisfaction after an unpleasant situation. 
The unjust verdict left a bad taste in the mouth of the community.
Pro Tip 2/3Metaphorical Use
It's a metaphor that compares bad experiences to the physical sensation of an unpleasant taste. 
The movie's ending left a nasty taste in my mouth; I expected something better.
Pro Tip 3/3No Real Taste
The phrase isn’t referring to actual taste, rather it's about a lasting, negative impression. 
Their rude comments left a bad taste in her mouth.