Okay… So Brad (Bier brauer) sent me a couple of his beer to taste, an Oktoberfest and an Alaskan amber clone. They arrived intact today, and I set them into the fridge and just got through tasting them both late this evening. FWIW, I am a BJCP Recognized judge with “a lot” of experience. Brad, I do hope you’ll understand why I am posting this publicly, as this is really just the next stage of the discussion in this thread. And, so, here’s what I can tell you all, but primarily for Brad’s benefit:
First of all, the issue is certainly NOT due to:
acetaldehyde
astringency/tannins
chlorophenol
contamination
I was also somewhat surprised that the similarities between beers were NOT very obvious. Each beer was very distinct and unique in character, as one should expect for two distinct styles/recipes. However, upon a little pondering, I think I might have figured things out… The two beers did seem to share just a very slight tartness. More on that later. So okay… tasting notes on the two beers…
The Oktoberfest has an unusual lemony citrus flavor and slight tartness that you wouldn’t expect in an Oktoberfest beer. For this one, I picked up the lemon and tartness up front, not in the finish. It was also very bitter – too bitter for the style, and the bitterness lingered. It is hop bitterness, NOT astringency – I know the difference. I feel like the lemony flavor must be from the hops that were used. Brad, can you tell me what hop additions you used in the Oktoberfest? And if you can recall, were these American hops or imported German hops? That might make a big difference. As for the tartness… It is just a slight tang and not anything like vinegar or lactic acid or anything anywhere close to that, just very very slight, and almost imperceptible. With no real reason for this to have happened, my hypothesis is that there might have been just a wee bit too much specialty malts. There was a fairly high amount of caramel detected, again more than would be expected for the style, and I know crystal/caramel malts if used in high proportions will have a tendency to reduce pH. Add on top of that the known use of the 5.2 pH stabilizer, which I discovered is quite tart with a sort of citric acid flavor, and the conclusion I have is that one or both of these conditions might be the culprit(s). Brad, if you could please post the recipe, it might be very telling indeed. Or maybe not. Worth a shot anyway. In the future, Brad, I would tone down the bittering and flavor hop additions, as well as any caramel or other specialty malts that were used. If you used any melanoidin, I believe that could also have contributed to the low pH and relatively high malty flavors other than bread crust and toast which would be more appropriate for the style. All things considered, it was still a pretty darn good beer and I could drink a lot of it. Very nice toasty finish and aftertaste. No huge flaws. I scored it a 27 overall. Good effort.
The Alaskan Amber clone, I felt, was cloyingly sticky sweet, and full-bodied, with a ton of caramel malt. If I had to guess, I’d say roughly 20% crystal malt was used, and perhaps even more. Brad, please post this recipe as well, unless I am way off in which case let’s not tell anyone! 
This beer had no lemony flavor or even much bitterness to balance it out, but had even more of that odd tangy tartness than the Oktoberfest. Again, no astringency or major off-flavors. For this beer, the tartness lingered… and lingered… long into the aftertaste. Again, it’s not hugely obvious like a lambic or anything like that, but just a tanginess. Reminds me of after having consumed a couple of Cokes, that tangy film on the roof of your mouth that remains even 30 minutes later. I felt this beer made the issue almost clear as crystal – it seems too much crystal malt was used, which likely reduced the pH significantly… and then knowing that the 5.2 pH stuff was used, that just might have added to the issue even more. Take Denny’s advice and throw that 5.2 stuff in the garbage. I’ll do the same with mine. It just doesn’t work. But also reduce your specialty malts.
So the themes are consistent. I think there’s too much caramel malt going on here. Cut it in half, or whatever, and you might be well on your way to better beer. Playing with water and salt additions would also be a good idea to ensure your mash pH is where it needs to be. But I’m not convinced that this is solely a water issue. I think it’s primarily just too much specialty malts. Use more base malts. And I’m still not certain what’s up with that lemony thing. I guess if you had used American grown Hallertau or Tettnang hops or whatever rather than German grown, the terroir might have imparted a slight citrusy character, which is not terrible but just might not have been what you expected. If you are seeing citrus in ALL of your beers, well… maybe it’s that 5.2 stuff after all. Next taste of your beers, consider whether it is a citrus flavor, or just a tangy flavor, or both. The causes might be different and might get confused. Citrus is probably hops. Tang is probably either that 5.2 stuff or the wrong pH.
So anyway… I don’t know if all this helps, but these are my humble thoughts based on the two beers that I tasted tonight.
