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Cleaning a soda keg


Rich Kragness • Pittsburgh, Pennsylvania asks,

I recently made a 10-gallon batch of Pilsner and bottled it in two five-gallon Cornelius kegs. I used the triple decoction technique and it tasted great, at least the first keg. I had previously used the second keg for making birch (or root) beer, so the beer in that keg has a hint of birch beer flavor. This is definitely not desirable for a traditional Pilsner. What can I do to improve this batch? I can drink it, but it is not suitable for guests! The more important question is, how do I get the birch beer flavor out of my keg? I have soaked it for 20 minutes with dilute bleach (yes, I know bleach is a no-no) and for 10 days with dilute TSP. I can still smell it. What do you suggest?

Ah, the old birch-beer beer. This reminds me of a time when I screwed up a beer experiment with the remnants of a root beer experiment. We had three groups in our
Response by Ashton Lewis.