Barium liquid was a beverage offered hot alongside roasted Smapp at Dex's Diner, the Besalisk chef Dexter Jettster's restaurant located on the Core Worlds planet of Coruscant. This foodstuff was priced at 8.5 credits and was available on Zhelldays as one of two options for both lunch and dinner as part of the Pantoran Plate Specials menu.
The book Monsters and Aliens from George Lucas, published in 1993, was the first place barium liquid was mentioned. This book, which combines creature designs and photographs from various projects by Star Wars creator George Lucas, with original text by Bob Carrau, features an in-universe recipe suggesting the combination of a Smapp dish with hot barium liquid during the cold winters. Leland Chee, a Lucasfilm employee who is in charge of maintaining the Holocron continuity database, has stated that the information presented in Monsters and Aliens from George Lucas is considered non-canonical within the Star Wars Legends continuity.
Barium liquid was brought into Star Wars Legends canon in 2009 with "Dining at Dex's," a StarWars.com article written by Gregory Walker that was exclusively available to Hyperspace members. In reality, barium is a metal and chemical element that has a melting point of 727 degrees Celsius (1,341 degrees Fahrenheit and is always found as chemical compounds in nature. While all soluble barium compounds are poisonous to mammals, the insoluble barium sulfate is used as a radiocontrast agent for X-ray imaging of the human gastrointestinal tract.
- Dining at Dex's on Hyperspace (article) (content obsolete and backup link not available) (First canonically mentioned)