OK, I think I MUST have something, perhaps a measurement error, wrong here. But I can't find it.
I made a Mirror Pond clone that I made before. Used S-04 the first time, but the yeast was bad and never took off. So I threw S-05 in and it made a great beer that finished at about 1.009.
This time I used S-04, and the beer finished at 1.005-1.006!!! That's with starting at 1.050! That would mean, what, 88%? If anything, I thought S-04 should finish higher, not lower than S-05.
Now, I did mash at a pretty low temp both times, 151 F. dropping to 149F in 1 hour. I fermented at 62F (temp on glass carboy). The two other differences (other than yeast) was that I had adjusted the chloride/sulfate ration to be a bit more towards "balanced" malt to bitter instead of "very bitter", and I got alot of trub into the primary fermentor. But I can't fathom this kind of attenuation.
I did take the final reading after transferring into the keg, and I used a refractometer for both the initial and final readings. Yes, I adjusted the conversion from brix to S.G. by including the initial S.G. and using two different calculators, to be certain. And I calibrated the refractometer just before each reading using distilled water.
I usually get good attenuation, but i can't fathom this reading, even mashing as low as I do. So.... any thoughts on what went wrong? Could it be real? Is it a measurement error? Temperature error?
It does tastes pretty bitter on the tongue for a beer that hasn't carbed yet. I guess that would seem that way if, in fact, it's really that dry......
Rich
I made a Mirror Pond clone that I made before. Used S-04 the first time, but the yeast was bad and never took off. So I threw S-05 in and it made a great beer that finished at about 1.009.
This time I used S-04, and the beer finished at 1.005-1.006!!! That's with starting at 1.050! That would mean, what, 88%? If anything, I thought S-04 should finish higher, not lower than S-05.
Now, I did mash at a pretty low temp both times, 151 F. dropping to 149F in 1 hour. I fermented at 62F (temp on glass carboy). The two other differences (other than yeast) was that I had adjusted the chloride/sulfate ration to be a bit more towards "balanced" malt to bitter instead of "very bitter", and I got alot of trub into the primary fermentor. But I can't fathom this kind of attenuation.
I did take the final reading after transferring into the keg, and I used a refractometer for both the initial and final readings. Yes, I adjusted the conversion from brix to S.G. by including the initial S.G. and using two different calculators, to be certain. And I calibrated the refractometer just before each reading using distilled water.
I usually get good attenuation, but i can't fathom this reading, even mashing as low as I do. So.... any thoughts on what went wrong? Could it be real? Is it a measurement error? Temperature error?
It does tastes pretty bitter on the tongue for a beer that hasn't carbed yet. I guess that would seem that way if, in fact, it's really that dry......
Rich