I just started paying attention to water chemistry with my last batch that I brewed yesterday, but in all the excitement of adding salts and acid, I failed to look at the chloramine concentration. I'm brewing with St. Louis water, which the water report states has about 2 ppm of chloramine. I haven't been able to find anything yet that states what concentration begin to start causing phenolic flavors, but this could be the culprit of the off flavors in my first two batches.
These first two were extract batches, and I just assumed the little twang flavor was either from under-pitching, no temperature control, or extract twang, though looking back it could be from chloramines. With doing AG, would heating the mash/sparge water help drive them off, or would a full boil be necessary? I did just bottle my first AG batch this weekend though (chocolate stout), and it didn't seem to have any off flavors at all. I have a NB Ranger clone and American IPA sitting in fermenters right now, and I'm kinda worried these are susceptible to the dreaded phenols.
For those of you who want the short and quick:
What concentration of chloramines is detrimental to beer?
Does heating the water drive them off, or does it need to be boiled? Edit: Just read you can't boil chloramines off. Darn.
From now on, Campden tablets will be going into every batch I brew.
Also, I'm using WLP001 and Pacman, kept around 62*F for the first week of fermentation, so hopefully that'll keep the yeast phenols to a minimum. Would dry hopping the crap out of them help mask the off flavor at all?