What is the problem with using a flavored kombucha as a starter?
There's two reasons for preferring the original instead of the Synergy version:


Most people make kombucha with a neutral base and then put in additional flavors when bottling. By starting with a pre-flavored kombucha, it gives you less flexibility in the flavors you might chose for yourself. For example, if you wanted to make a strawberry &amp; basil kombucha, that might not want the raspberry and ginger in the Synergy bottle you selected.
The original version, since it's 100% kombucha instead of having other juices in it, gives you the best chance of forming your own mother as quick as possible. The Synergy should still work, but may take longer to generate a useful mother.


In any case, the Synergy bottle should still work, and after a few batches I doubt there will be much residual effects from the juices in it. It's just that using the original will give you a neutral kombucha base faster than the other bottle.