A Tzartak aperitif is a drink that is prepared half a degree below the body temperature of the person it is served to.
Tzartak aperitifs were the most expensive drink at Quark's on Deep Space 9. In 2376, Frool made a Tzartak aperitif for a Kobheerian but served it at the body temperature of a Lissepian, five degrees cooler than a Kobheerian's temperature. Quark planned to charge Frool for his mistake by taking money out of his salary. (DS9 - Worlds of Star Trek: Deep Space Nine novel: Ferenginar: Satisfaction is Not Guaranteed)