Dr. Schulze says that it is fine to keep juices in the fridge. However, as the previous poster notes, much of the vitality is lost within 20-30 minutes, and indeed, drinking cold drinks is far from advisable.
If you need to refrigerate your juices, please take care to return them near to room temperature before consuming them.
How are you enjoying the slippery elm gruel? It's nice, isn't it...;)
(And I apologize for the late response. 71h?! Just shocking...)