Ever since I began doing all-grain mashes, I have been having very high final gravities. My second to last batch is very sweet and I decided to finally see what I could do about it. I am trying to fix that batch (an IPA) and also gather some useful data on my newest batch (a Rye IPA):
First, the IPA:
78% 10.5lb American Two-row Pale
11% 1.5lb Wheat Malt
7% 1lb Flaked Barley
4% 0.5lb CaraVienne
The mash was 60 minutes at 154 degrees and I used iodine tests to confirm that the conversion was complete. I got about 70% efficiency. OG was 1.069 and the FG was 1.026. It was supposed to be down in the 1.017 area. I am using both a hydrometer and a refractometer to measure the gravities. I used some yeast that I had gotten from a local brewery. I had used this yeast in a stout previously (OG 1.048 FG 1.020 also higher than estimated) and racked the IPA on top of the trub from the stout's primary. Probably not the smartest thing to do but I didn't have the time or inclination to wash it just then.
I oxygenated the wort prior to pitching by dumping it back and forth between two buckets a few times. After one week it hit the FG above, I washed the yeast from the primary this time and stored it in the fridge and I racked the beer to a carboy and it hasn't moved since. Looking back, it seems like I racked too soon. I tossed some washed yeast back into the carboy hoping that it would continue fermenting, but it hasn't done anything in the last 2 days.
This last weekend I did the rye IPA:
52% 8lb American Two-row Pale
32% 5lb Rye Malt
6% 1lb Flaked Rye
6% 1lb Flaked Barley
3% 0.5lb CaraVienne
This time I did a starter 24 hours before. I used 1 cup DME in about a liter of water, some of my washed yeast and let the stuff get started overnight.
I mashed for about 80 minutes at 152 degrees and got complete conversion indication from the iodine test. The OG was 1.060, about 60% efficiency. This time I did a fast ferment test too. I took about a cup of wort and added 1/2 tsp of bread yeast. It's been going for two days and is showing a pretty lousy final gravity: 1.026. Maybe its not done yet...
I've been shaking/agitating the carboy, the ferment test and the bucket with the new beer, and I think I'm concluding that my mash is the problem here. All my batches' FG have been too high (not just the three I described here) and the only common denominator is the mash. I've used dry yeasts, liquid yeasts and the yeast from the brewery and now bread yeast too.
If this is the case what can I do next? I have 2 10 gallon coleman coolers and am using a CPVC manifold in the mash tun and a CPVC 'sprinkler' on the HLT. I usually use hopville's calculator to find the strike temp, dump in the grain, mix it up, make sure its between 150-154 degrees, leave it for 20 minutes and then give it a little going over with a long spoon, leave it for another 20, then cut it up again, then leave it for the final 20 or so. I set up the HLT with 5 gallons of water at about 180 degrees and then just sparge the whole thing very slowly (30 minutes or so?). I get about 6.5 gallons out then toss it on the flame.
Is it possible that I am getting way too many unfermentables out of the mash? Could this explain the high FG? Can I do some tests to confirm that my mash technique is to blame? I could do some small scale stuff but I figured some hints might get me going in the right direction.
First, the IPA:
78% 10.5lb American Two-row Pale
11% 1.5lb Wheat Malt
7% 1lb Flaked Barley
4% 0.5lb CaraVienne
The mash was 60 minutes at 154 degrees and I used iodine tests to confirm that the conversion was complete. I got about 70% efficiency. OG was 1.069 and the FG was 1.026. It was supposed to be down in the 1.017 area. I am using both a hydrometer and a refractometer to measure the gravities. I used some yeast that I had gotten from a local brewery. I had used this yeast in a stout previously (OG 1.048 FG 1.020 also higher than estimated) and racked the IPA on top of the trub from the stout's primary. Probably not the smartest thing to do but I didn't have the time or inclination to wash it just then.
I oxygenated the wort prior to pitching by dumping it back and forth between two buckets a few times. After one week it hit the FG above, I washed the yeast from the primary this time and stored it in the fridge and I racked the beer to a carboy and it hasn't moved since. Looking back, it seems like I racked too soon. I tossed some washed yeast back into the carboy hoping that it would continue fermenting, but it hasn't done anything in the last 2 days.
This last weekend I did the rye IPA:
52% 8lb American Two-row Pale
32% 5lb Rye Malt
6% 1lb Flaked Rye
6% 1lb Flaked Barley
3% 0.5lb CaraVienne
This time I did a starter 24 hours before. I used 1 cup DME in about a liter of water, some of my washed yeast and let the stuff get started overnight.
I mashed for about 80 minutes at 152 degrees and got complete conversion indication from the iodine test. The OG was 1.060, about 60% efficiency. This time I did a fast ferment test too. I took about a cup of wort and added 1/2 tsp of bread yeast. It's been going for two days and is showing a pretty lousy final gravity: 1.026. Maybe its not done yet...
I've been shaking/agitating the carboy, the ferment test and the bucket with the new beer, and I think I'm concluding that my mash is the problem here. All my batches' FG have been too high (not just the three I described here) and the only common denominator is the mash. I've used dry yeasts, liquid yeasts and the yeast from the brewery and now bread yeast too.
If this is the case what can I do next? I have 2 10 gallon coleman coolers and am using a CPVC manifold in the mash tun and a CPVC 'sprinkler' on the HLT. I usually use hopville's calculator to find the strike temp, dump in the grain, mix it up, make sure its between 150-154 degrees, leave it for 20 minutes and then give it a little going over with a long spoon, leave it for another 20, then cut it up again, then leave it for the final 20 or so. I set up the HLT with 5 gallons of water at about 180 degrees and then just sparge the whole thing very slowly (30 minutes or so?). I get about 6.5 gallons out then toss it on the flame.
Is it possible that I am getting way too many unfermentables out of the mash? Could this explain the high FG? Can I do some tests to confirm that my mash technique is to blame? I could do some small scale stuff but I figured some hints might get me going in the right direction.