Trouble reaching FG

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Cos

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This is a follow-up from a couple weeks ago.
I have 2 lagers brewed 1 week apart. Both started at 1.044 and fermenting at 53 deg.


1st. lager was in primary 7 days, racked to secondary at 1.016
2 weeks later in secondary at 53 deg. it's still 1.016

2nd. lager was in primary 15 days, racked to secondary at 1.016
(it hit 1.016 after 4 days in primary).

Wyeast 2035 in one, WLP940 in the other. Both should have hit 1.011.

Could this be an aeration problem?
 
Wow- that's less than 63% attenuation. The WLP940 should hit 74% or so. The 2035 should hit 75%.

Maybe your recipe used lots of unfermentables? Or maybe you racked too soon. I always rack when I reach final gravity, after the diacetyl rest. Did you do a d-rest?
 
I tasted for butter flavor and had none, so no d-rest. I pitched at 64 deg. and immediately put in 53 deg frig. It took about 24 hrs before the brew reached 53.

The 2nd. lager didn't drop at all between day 5 and 15 in primary, so I don't think it was going to drop anymore.

Has to be an aeration problem or too small a starter.
I used a 2 quart starter in both.
 
I've never brewed a lager, but from all that I've read, I believe 1 week is premature for racking. Lagers are cold fermented, and even though lager yeast hold up to the cooler temps, it does slow fermentation down.

there's nothing wrong at all with letting a beer sit on the yeast for 3+ weeks. its not gonna autolyze in that time frame, and its gonna help insure you finish fermenting.

I guess the 2nd lager did sit over 2 weeks without dropping (sorry, I been tapping the keg tonite :)

show us the recipe and if its AG, include your strike temp(s). and have you checked your brew thermometer? if you're a little off on temp that'll change the fermentability of your brew.
 
I've done 3 partial mashes. 1 ale that reached FG just fine. My technique and temps were the same for all 3 batches. Recipes are basically the same as well.

3.5 lb 2-row
.5 lb crystal 60
3 lb dme
2 oz tettnang
1 oz hallertauer

My mash temp started at 158 and ended at 154 45 minutes later.
Sparged with 168 water for 10 min.
Mash was 6 qts. Sparged 2 rounds, 5 qts each.

Instrucitons were taken straight from BeerSmith software.

The only thing different between the ale and the lagers was the yeast starters.
On the ale, I did a 1q starter and pitched the whole thing.
On the lagers, I did 2q starters and then chilled 24 hours and decanted.
However, I may have poured off a lot of suspended yeast when I decanted. Should have given it another 24-48 hrs.

Perhaps I just underpitched because I decanted.
 
It could be that just most of the yeast flocculated. I had similar situation with my last lager which got stuck at 1.020 after 2 weeks of fermentation (starting from 1.054). It was still in primary and I simply gave carboy a bit of a swirl. In a week it got down to 1.012. I used Wyeast 1124. When you moved to the secondary did you save any yeast? Any wort leftover? You can make like a small starter and drop it in to you secondary when it reaches high krausen. It will introduce fresh yeast in to you beer which should help ferment to TG.
 
Starting at a high temp like 158f will result in a lot of long chain sugars that will produce a sweet lager and a high final gravity. Not sure if I'd want that in my lagers.

Next time try mashing at 152f or even lower at 150f.
 
yeah, temperature affects fermentability. 158F would favor more sweetness, less fermentability. lower temps, especially just under 150F will yield a dryer beer, less residual sweetness.

I shoot more for about 154F dough-in, and it usually drops no more than 3 degrees in one hour.

if your thermometer isn't calibrated, you might even be a few degrees above 158F which'd have even more of an effect on the final fermentability.
 
The temperature thing doesn't explain why my ale reached 1.012 after 7 days.
The higher temp is supposed to give a more full body beer, which I prefer.
Next time I'll try a lower temp.
 
I mash my Octoberfests and Maibocks at a high temp, as a rule. I'm still wondering if maybe the brand of DME you used just wasn't as fermentable as some others. Really, 1.016 isn't a bad place to be. I'd just be concerned that fermentation would restart at an inopportune time, like in the bottle. I've bottled quite a few beers at 1.016 but usually the attenuation is higher.

If it were me, I'd still keep it at 53 degrees for a couple more weeks just to see if it'll drop any more. I wouldn't start lagering until after that.
 
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