first all grain low attenuation

[tintmaster88]

I brewed a fat tire clone that I got from byo 3 weeks ago. I mashed at 155 and got 83% efficiency. I made a 2l starter with wlp060 the night before. The next day it wasnt doing anything so I checked the slant and saw it was expired by a month. So I went and picked up wlp001 and added it to the starter. I brewed the beer and added the starter which wasnt at high kraussen but was showing signs of activity. Pitched yeast at 60 and raised up to 65. The temp did vary between 60 and 68 for a couple of days before I finally got it to settle around 65. 2 weeks later it was at 1.022 and showed no signs of activity. I swirled and raised the temp to 72. Another week and still at 1.022. Beersmith says my attenuation is at 58%. What can I do and what was the likely cause of this? I wouldn't have worried too much but I brewed a batch of apa a week ago and it seems to be stopped at 1.021 also. Should I start mashing at a lower temp? What's the problem here?

[dmtaylor]

Two things: You mashed at too high a temperature, and you didn't give the starter enough time.

Also, what was your mash time? An hour would be sufficient, but if you only mashed for say 30 minutes, this will affect attenuation in a big way.

Next time, mash at 148 F for an hour, and let your yeast starter go for 2 or 3 days. I can 99% guarantee that you won't end up with the same problem again.

[tintmaster88]

I mashed for 60 minutes. The recipe called for a 155 mash temp. Maybe my setup is different and I need to mash lower. I'll try that. My apa has done the same thing and I mashed that one at 154. I didn't have time to do a starter so I added 2 vials of 001 which is what the pitching calculator called for.

[brewinhard]

Double check to be sure that your thermometer used for mashing is fairly accurate (never trust them until you calibrate). You should run yours next to someone who you know has a working good thermometer and hits their numbers accordingly and adjust your thermometer to theirs. This will at least put you in the ballpark. With that being said I would say that 155 and 154 for a fat tire clone and pale ale respectively seem a bit high especially if you are looking for them to finish around 1012.

[tintmaster88]

You nailed that one. I have 2 thermometers and both of them are reading 10 degrees low. So I really mashed at 165. Now what? Has anybody used enzymes to break down the unfermentables? I could also brew another batch but mash really low so it's nice and dry and mix it with this one to meet in the middle. I'm afraid if I bottle it the way it is it will just sit around and I won't drink it.

[brewinhard]

Welll..... there are some choices here. I do not recommend adding Beano, because as far as I know, it does not stop breaking down unfermentables until there is nothing left (ie very dry beer). Your idea of mashing extra low, say maybe 147-148 for 90 minutes to allow a good conversion and then blending the two beers sound like a good idea. If it were me, and this has happened to me before when I have made a couple of tripels that didn't finish dry enough, I would add a package of Brettanomyces and let it eat its way through the remaining sugars. But, then you are opening a whole new can of worms (like needing separate equipment like racking canes, tubing, etc).

You could always dilute some of the beer with distilled or preboiled, chilled water. This is how many great American breweries make their macro lagers (bud, coors, I believe). Just try to figure out the best you can what a good proportion would be to thin the beer enough. You wouldn't need too much water to get it down to where it would be good.

Or, just carbonate it a bit higher so the dextrinous body does not shine through as much, invite some friends over and have a party. People will love the beer, and meanwhile make a couple more batches with your new calibrated equipment.

Way to tackle your first all-grain issue! Now go, brew again, brew hard, and brew strong!

-Cheers,
Brewinhard

[Steelers&Beer]

take it all the way through fermentation and try it, it might be friggin great...you just never know...keep brewing!

[Crackin]

Bottle it, drink it, it will be fine. How did you come to realize that both your thermometers were 10 degrees low? Another problem I see here, is that your fermentation temperature were swinging too much. If it gets up to 68 and then goes back to 60, guess what, a bunch of yeast will drop out. Even it if goes back up to 65, a portion of your fermentation workforce, has already walked off the job.