Residual soda in beer?

Ok, so I made some sasparilla soda and carbonated it with a stone. All went well. Then when I made beer, I took the stone from the soda keg, Cornelius keg, and put it in the beer keg. I now have a strong taste is sasparilla in the beer I made and odor. Could the residual soda in the stone flavor the beer keg. I have all the co2 lines for the kegs sliced together with no check valves in it. I plan on installing check valve to rule back feed out, but I don’t think that’s the issue. Any other thoughts out there?

There is a brewery making a lot of money selling root beer flavored beer. You may have something there.

I think the only way you get back feed through gas lines if you run two or more kegs.
Without check valves the gas can move between kegs as you pour to equalize the head space.

If you’re getting the taste from the same keg, then the keg or stone would be the culprit.
Did you boil the stone?

Boil the stone??? First time I used one never heard of boiling it. I guess the best thing I can do is get a stone for each keg and get some check Valves
How long would one boil it for?

How did you sanitize it? The stone is numerous layers of SS and beer will get into the pores of the stone. You should boil it after every use AND while boiling it blow your air through it. AVOID TOUCHING THE STONE WITH YOUR BARE HANDS OR IT WILL CLOG THE PORES.

And you don’t have to use a stone to carb your keg. Set your regulator to the correct volume of CO2, come back 2 weeks later, and your beer will be carbed. Better yet, you CO2 will be hydrated producing a better head and beer. Even with your stone yor CO2 needs hydrated.

I boil mine for 10-15 mins., but I just use it for aeration.