The Liquorice aroma is very easy to identify as it is very unique and recalls candies. In Red Wines, it is usually a tertiary aroma generated during the barrel-aging process.
It is very evident in some aged, high-quality wines. It can be easily detected also at the bottom of a glass after the wine has been drunk.
Some of the grape varieties which best express this aroma are Nebbiolo, Aglianico, and Sagrantino.