Many people think certain artificial sweeteners have an unpleasant aftertaste.
Then coughed at the tart aftertaste.
In high concentrations, stevia can have an almost licorice-like aftertaste and it can be bitter.
It was far too sweet and had a bitter aftertaste.
When tasted neat there is an initial whoosh of alcohol followed by an aftertaste of apples and French chalk on a new inner-tube.