Pilgarlic
Well-Known Member
Thursday night I had a delicious APA that I had bottled 9 days earlier. By Friday night, I opened another and it showed that this beer has fallen
prey to the mysterious off flavor/contamination that has been
afflicting my hoppy beers for some time. I think I've tracked it down:
Here's what I know:
1) My hoppier beers, and only my hoppier beers, have, for some time,
gone into the bottle tasting good and ended up with a tart, offensive
off-flavor that some have described as somehow "belgian".
2) Along with the change in flavor, there is an appreciable increase
in carbonation.
3) One of my hoppier beers that had developed this flavor was entered
into a recent competition and two of the judges identified the
flavor as "phenolic".
4) The off-flavor has, even to my rough palate, an aftertaste that is just
slightly evocative of "band-aid" or plastic.
5) The most recent affliction, Crunchf*cker Pale Ale, tasted great on
Thursday night, and by Friday night had gone markedly bad.
6) All of the afflicted beers had been dry-hopped.
I am persuaded that the off-flavor is phenols. Phenols come from MANY
potential sources, some chemical and some biochemical. Among the most
common sources are water (chlorine and chloramine) and wild yeast.
The fact that the flavor (and the increased carbonation) develop in
the bottle suggests strongly that the source is a biological
contaminant. The most common biological agent producing phenolics in a
beer is wild yeast. Wild yeast would explain the flavor and the
carbonation increase.
Why only the dry hopped beers? When I dry hop, I lift the lid, or
remove the stopper, from the fermenter, drop in the pellets and
replace the lid or stopper. Other than dry hopping, I almost never
open a fermentor in the fermentation chamber.
I have used my fermentation chamber in the past for storage of frames
from my beehives. Honey is notorious for harboring wild yeasts and,
when diluted, it almost immediately begins to ferment. Honey dripped
from the frames while they were stored in my chest freezer (cleaned but not sufficiently?).
My theory is that my ferm chamber is seriously infected with wild
yeast and, when I open the fermentor to dry hop, suspended spores are
admitted.
The Crunchf*cker wouldn't clear in primary. Wild yeasts are known to be
non-flocculant. I fined it with gelatin, dropping the yeasts out of
suspension and leaving them behind when bottling. It took a bit over a
week in the bottle for them to revive and produce the off-flavors and
CO2. (Contrary evidence: the Crunchf*cker is still clear).
Having an infected brewery is a p*sser. Having a theory that seems to
fit the facts is reassuring. If you're inclined, 1) punch some holes
in the theory, or support it, and 2) suggest how you would go about
eliminating the wild yeast from my fermentation chamber.
Thanks for listening.
prey to the mysterious off flavor/contamination that has been
afflicting my hoppy beers for some time. I think I've tracked it down:
Here's what I know:
1) My hoppier beers, and only my hoppier beers, have, for some time,
gone into the bottle tasting good and ended up with a tart, offensive
off-flavor that some have described as somehow "belgian".
2) Along with the change in flavor, there is an appreciable increase
in carbonation.
3) One of my hoppier beers that had developed this flavor was entered
into a recent competition and two of the judges identified the
flavor as "phenolic".
4) The off-flavor has, even to my rough palate, an aftertaste that is just
slightly evocative of "band-aid" or plastic.
5) The most recent affliction, Crunchf*cker Pale Ale, tasted great on
Thursday night, and by Friday night had gone markedly bad.
6) All of the afflicted beers had been dry-hopped.
I am persuaded that the off-flavor is phenols. Phenols come from MANY
potential sources, some chemical and some biochemical. Among the most
common sources are water (chlorine and chloramine) and wild yeast.
The fact that the flavor (and the increased carbonation) develop in
the bottle suggests strongly that the source is a biological
contaminant. The most common biological agent producing phenolics in a
beer is wild yeast. Wild yeast would explain the flavor and the
carbonation increase.
Why only the dry hopped beers? When I dry hop, I lift the lid, or
remove the stopper, from the fermenter, drop in the pellets and
replace the lid or stopper. Other than dry hopping, I almost never
open a fermentor in the fermentation chamber.
I have used my fermentation chamber in the past for storage of frames
from my beehives. Honey is notorious for harboring wild yeasts and,
when diluted, it almost immediately begins to ferment. Honey dripped
from the frames while they were stored in my chest freezer (cleaned but not sufficiently?).
My theory is that my ferm chamber is seriously infected with wild
yeast and, when I open the fermentor to dry hop, suspended spores are
admitted.
The Crunchf*cker wouldn't clear in primary. Wild yeasts are known to be
non-flocculant. I fined it with gelatin, dropping the yeasts out of
suspension and leaving them behind when bottling. It took a bit over a
week in the bottle for them to revive and produce the off-flavors and
CO2. (Contrary evidence: the Crunchf*cker is still clear).
Having an infected brewery is a p*sser. Having a theory that seems to
fit the facts is reassuring. If you're inclined, 1) punch some holes
in the theory, or support it, and 2) suggest how you would go about
eliminating the wild yeast from my fermentation chamber.
Thanks for listening.
