I seem to be getting good attenuation when using WLP001 in my recent IPA's. OG is 1.051 and FG turned out 1.009. The problem is that I continue to get a somewhat of a unpleasant bitter taste, somewhat alcoholic.
For this last batch, I adjusted the grist and sparge water to ~ 5.2 at mash/sparge temps with Lattic Acid and Acid malt.
Fermentation temps was around 64-65 for the pitch, but naturally increased to around 68-70 during primary fermentation. WLP001 recommends a temp of 68-72, so I don't feel like I fermented too warm.
This particular batch was better than my last one, which had a more intense unpleasant bitterness/alcoholic taste. Opening the fermenter and smelling it also gave the aroma.
Anyone have experience with WLP001 and this problem? Or this off-flavor in general?
One thing I noticed is that despite a really thick Krausen during fermentation, the airlock wasn't moving. Is this trapping compounds that should be escaping through the airlock?
Additionally, I harvested this yeast from the previous batch, but I tasted it before adding it to this new batch. There was no noticeable alcoholic taste.