advice? possible infection?
Posted: Tue Aug 30, 2016 9:45 am
First, for sanity, I may need someone to taste samples of two beers fermented with WLP090, as I have never used it before -- though it is supposed to be a neutral american ale flavor.
Something went wrong -- Either I somehow managed to infect a batch in a glass fermenter, and therefor the yeast harvested from it was also infected, or the yeast was bad to start, or amylase power can completely screw up a beer? I'm in danger of having to dump 15 gallons.
process:
I split a batch of IPA (had a mash temp problem, hence the high FGs) into two fermenters, one PET and one glass. Both were cleaned with a mark's keg cleaner / PBW, then hit with starsan.
The PET / WLP644 was kegged at ~1.015 at ~3 weeks, and was great.
The glass / WLP090, still measured 1.015 at 4 weeks. At this point I believe I tasted the gravity sample, and noticed nothing bad, just not "dry" enough. I then added a 1/4 tsp amylase to see if it would help, as an experiment.
A week later, there was no gravity change, so I kegged it, added a little gypsum for balance, primed with sugar, and sealed for 2 weeks. I don't recall if I tasted it at kegging/priming time, but I probably would have before adjusting the sulfite level.
The yeast cake at this point was harvested, and used to ferment 10 gallons of centennial blond in 2 6gal pails, at 65F. They finished at 1.010, but with a quite unpalatable flavor/aroma which I can only describe as "insufficiently conditioned / green beer". I kegged and cold crashed 5gal, and though it seems to have reduced the flavor, I am pretty darn sure that something is really wrong in it.
At this point, I threw the WLP090 IPA keg in the keezer, and sampled it. I believe that the same bad taste has appeared in it (possibly to a lesser extent), but would like a second opinion.
Open to comments / suggestions:
I believe that I can rule out the following:
-brew/boil hardware (triclamp, recirculated with PBW then water, disassembled and cleaned between batches, and recirculated with boiling water during boil).
-fermentation vessels (as each 5gal portion in this post used a different vessel)
On further investigation, it appears that the BSG Amylase from BIY is actually alpha, so it would do nothing at all to drop FG from too-high mash, as that was the alpha amylase active range. http://bsghandcraft.com/index.php/proce ... 15-oz.html says "Breaks 1,4 linkage in starch during liquefication, producing dextrin and a small amout of maltose. Leaves 1,6 links, therefore self-limiting" which is what alpha does.
That doesn't explain my problem, but it explains the failure to drop gravity.
Something went wrong -- Either I somehow managed to infect a batch in a glass fermenter, and therefor the yeast harvested from it was also infected, or the yeast was bad to start, or amylase power can completely screw up a beer? I'm in danger of having to dump 15 gallons.
process:
I split a batch of IPA (had a mash temp problem, hence the high FGs) into two fermenters, one PET and one glass. Both were cleaned with a mark's keg cleaner / PBW, then hit with starsan.
The PET / WLP644 was kegged at ~1.015 at ~3 weeks, and was great.
The glass / WLP090, still measured 1.015 at 4 weeks. At this point I believe I tasted the gravity sample, and noticed nothing bad, just not "dry" enough. I then added a 1/4 tsp amylase to see if it would help, as an experiment.
A week later, there was no gravity change, so I kegged it, added a little gypsum for balance, primed with sugar, and sealed for 2 weeks. I don't recall if I tasted it at kegging/priming time, but I probably would have before adjusting the sulfite level.
The yeast cake at this point was harvested, and used to ferment 10 gallons of centennial blond in 2 6gal pails, at 65F. They finished at 1.010, but with a quite unpalatable flavor/aroma which I can only describe as "insufficiently conditioned / green beer". I kegged and cold crashed 5gal, and though it seems to have reduced the flavor, I am pretty darn sure that something is really wrong in it.
At this point, I threw the WLP090 IPA keg in the keezer, and sampled it. I believe that the same bad taste has appeared in it (possibly to a lesser extent), but would like a second opinion.
Open to comments / suggestions:
I believe that I can rule out the following:
-brew/boil hardware (triclamp, recirculated with PBW then water, disassembled and cleaned between batches, and recirculated with boiling water during boil).
-fermentation vessels (as each 5gal portion in this post used a different vessel)
On further investigation, it appears that the BSG Amylase from BIY is actually alpha, so it would do nothing at all to drop FG from too-high mash, as that was the alpha amylase active range. http://bsghandcraft.com/index.php/proce ... 15-oz.html says "Breaks 1,4 linkage in starch during liquefication, producing dextrin and a small amout of maltose. Leaves 1,6 links, therefore self-limiting" which is what alpha does.
That doesn't explain my problem, but it explains the failure to drop gravity.