Illegal for pros

Northern Brewer General
1

I was reading an old issue of Zymurgy that had a recipe for Charlie P’s Bourbon Barrel Runnings Porter.

He adds the cleared sludge from a barrel to a porter. In the text he explicitly states that it is illegal for commercial brewers.

Any idea why? Just curious.

2

You are not allowed to “fortify” the beer with distilled alcohol.

3

OK, if the beer extracts it from the barrel naturally, it’s legal.