Confused...

[horsepowerwhisperer]

Second brew on this new 1/2 bbl system. Still figuring out how to keep my mash temp constant on this system, but I was particularly careful to watch my temps and make sure they didn't stray too far from 152. Target OG on this beer was 1.07. Admittedly, I didn't account properly for the 90 min boil evaporation and got an OG of 1.08. I added a starter (5L w/ 3 Wyeast 1318 packs). Fermentation was kicking in a few hours, but I added the balance of the volume in water after within 24 hrs to get the gravity down to normal.

Primary seemed to go really well. I took a reading when things started to slow down after a few days to one bloop every five seconds from my conical's blowoff tube. It came in at 1.03.

Two days later, once all activity had seemed to finally cease, I took another reading. Still 1.03. I brought the temp up a few degrees and shook the fermenter a little after reading this strain has a tendency to floc out early. Things kicked back up for a couple of days, and I agitated the wort every twelve hours. Took another reading tonight after bloopage had stopped again...1.03.

The beer doesn't taste bad; a little malty, but I haven't dry hopped yet.

Is my hydrometer bad? It's been sitting in storage for quite some time, but they shouldn't have a shelf life. It shows 1.0 in RO water, so it seems like it should be OK. But isn't it weird that there was no change in the SG after all that activity? Coincidentally, my first batch on this system also finished at 1.03. But I definitely boiled it down too long and overshot the 156 target mash temp on that one, so I wasn't terribly surprised.

Thanks for any insight!

 

[RM-MN]

Second brew on this new 1/2 bbl system. Still figuring out how to keep my mash temp constant on this system, but I was particularly careful to watch my temps and make sure they didn't stray too far from 152. Target OG on this beer was 1.07. Admittedly, I didn't account properly for the 90 min boil evaporation and got an OG of 1.08. I added a starter (5L w/ 3 Wyeast 1318 packs). Fermentation was kicking in a few hours, but I added the balance of the volume in water after within 24 hrs to get the gravity down to normal.

Primary seemed to go really well. I took a reading when things started to slow down after a few days to one bloop every five seconds from my conical's blowoff tube. It came in at 1.03.

Two days later, once all activity had seemed to finally cease, I took another reading. Still 1.03. I brought the temp up a few degrees and shook the fermenter a little after reading this strain has a tendency to floc out early. Things kicked back up for a couple of days, and I agitated the wort every twelve hours. Took another reading tonight after bloopage had stopped again...1.03.

The beer doesn't taste bad; a little malty, but I haven't dry hopped yet.

Is my hydrometer bad? It's been sitting in storage for quite some time, but they shouldn't have a shelf life. It shows 1.0 in RO water, so it seems like it should be OK. But isn't it weird that there was no change in the SG after all that activity? Coincidentally, my first batch on this system also finished at 1.03. But I definitely boiled it down too long and overshot the 156 target mash temp on that one, so I wasn't terribly surprised.

Thanks for any insight!

If you added heat to keep the temp at 152, you may have inadvertently made part of your mash temp much higher and effectively mashed part at 152 and part at 160. It takes very vigorous constant stirring if heat is added to avoid overheating part of the mash. You might have been better off just letting the temp change as it normally would as the majority of the conversion would have happened fairly fast.

 

[headfullahops]

Most of the issue probably does stem from the mash process as mentioned above, but you may also want to consider using a higher attenuating yeast strain like 1098 or WLP007. All things being equal, they will drive your FG down farther than 1318.

 

[IslandLizard]

WY1318 has an attenuation factor of 71-75%, which should have brought your 1.070 beer down to 1.017-1.021. Now some of those English yeasts floc out early, leaving you with sweet beer. I think lack of oxygenation may play a role in that, as could a slight temp drop at a critical point during fermentation.

I have a batch of 1.071 Pale Ale with WY1968, that's "stuck" at 1.024, which is in the upper range for its attenuation (67-71%). I racked it to a keg so I can rouse it more safely, and have been shaking and bubbling CO2 through it a few times the past few days. No budging, it must be done. At least it's had a good diacetyl rest at 75F.

Now intentionally mashing high (158F) didn't help the cause either. It tastes a bit sweet, but not cloyingly. Hopefully it contains more dextrins than sugars. I'm just going to dry hop it and make the best of it.

I never reckoned that the attenuation range of yeast could be such an important factor. I guess it's great for 1.050 and lower gravity beers. But for higher gravity ones it can ruin a beer.

Now after re-using these yeasts a couple times I noticed they start to behave differently. They don't floc out as quickly, stay cloudier longer, and attenuate better. Maybe we should take advantage of that and not pitch fresh cultures if we want higher attenuation. My old WY1968 culture got so bad it would take months to clear, that's the reason I started with a fresh batch this time. Same for 1098/1099.

 

[horsepowerwhisperer]

Thanks for the input, folks. Much appreciated! Concerning the mash, I'm actually recirculating it, so there shouldn't be enough time for the bottom wort to get too hot. However, I'm still working out the kinks on this new system. The wort's getting pumped through a HERMS coil in my HLT. I've tried setting the HLT temp a little above the mash temp to keep everything constant, but it doesn't seem to be working very well. I end up having to turn on a little direct fire periodically or crank up the HLT. Maybe wort's getting cooked going through the HERMS coil in the latter case? Maybe next time I should just bypass the coil and see what happens.
I'm also relying on the mash tun's dial thermometer; should I consider getting a better hand-held one and checking different points?

Regarding the yeast, good info on the 1318 strain. The beer is a Young's Special London Ale clone, and that's what the recipe called for. Perhaps my calculations were wrong, and the water I added didn't bring the OG down enough to reach 1.07.

I just thought it was weird to see activity (CO2 bloopage) for several days and have no change at all in the SG. It's still farting every twenty seconds or so.

Thanks again for your input!