Off flavor from high carbonates?

[chode720]

I have brewed several dark beers recently that have had a weird off flavor. My best guess from everything I have read is that its a sulfur issue. I had the issue when using wlp005, but only on beers above 25 SRM. I made an amber colored pumpkin ale and christmas ale with the 005 and didnt have the issue.

Why I ask about the carbonate level is because thats the only difference between these beers is the water treatments. I adjust the bicarbonates to around 250ppm for the darker beers to adjust for the mash pH, but the levels are much lower in the amber beers. Palmers book doesnt say anything about what too high bicarbonates can do and if they affect beer flavor, so Im curious if they would make a difference, or just a pH issue.

Everything else is the same with the beers (fermentation temps, oxygen levels, proper pitching rate, 3-4 weeks in primary) so im trying to figure out where the darker ones went wrong.

My only other thought is that the temp in my house is cold this time of year and I know after the dark beers finished fermenting, they quickly fell to the low 60s and this may have not given the wlp005 enough time to clean up the beer.

 

[Nateo]

When you adjust your mash pH, are you measuring with a meter or precision litmus strips? A lot of brewers more knowledgeable than myself say you should never add alkalinity to your mash. From my experience, I'd say this is true. Since buying precision test strips and testing my mash, I've only/always had to lower my pH, regardless of color, and I have a low RA in my water.