I use Zatarains Extract. I have tried several but the kids always pick this one as their favorite. I use around 3lbs sugar which I dissolve in around 3gal water. I chill to 40f and apply 28-30 psi for a couple days. This is close to 4 volumes of CO2. We like it between 3.5 and 4 volumes.
I have a separate party tap line I use but reused the keg if I need it for beer. I have not had an off flavor from root beer having been previously in the keg. I do soak it in PBW for an hour after it empties.
- Jomebrew
