Romulan Ale is an alcoholic beverage found in almost every Star Trek series. What color is this drink?

On the 1966 - 1969 Star Trek TV series, Romulan ale is known for being a highly intoxicating alcoholic beverage. It is entirely Romulan in origin with a characteristic blue color (ranging from a pale sky blue to a dark midnight blue). It takes a while to ferment and is a beverage with a powerful kick to a person's digestive system.

At its core, this drink is required to be made with Grain Alcohol (aka, Everclear). Also, it is clear that what one does during and after consumption of Romulan Ale is their overall and individual responsibility.

Doctor Leonard McCoy in Star Trek II: The Wrath of Khan used Romulan ale for "medicinal purposes." It was considered an illegal item to own and use in the United Federation of Planets (UFP), usually referred to as "the Federation", a fictional interstellar federal republic in the Star Trek series, composed of numerous planetary sovereignties.