I know that FBS does not disclose the caffeine content, if any, in FBS...but has anyone gotten a caffeine buzz from it? In other words, does the fermentation affect the caffeine from the coffee?
Alcoholic beverages can contain caffeine and still be legal. What makes it illegal is if the caffeine is added for the stimulating effect. As opposed to just being present as a result of the brewing process or as a necessary consequence in an attempt to add a certain flavor. For example, adding coffee or tea to a brew will add caffeine necessarily, but the coffee or tea would have to have been added for flavoring to make the resulting caffeine presence legal.
I know I've laid awake at night a few times after drinking an FBS an hour before. Can't confirm it's caffeine, but I think it probably is.