Stuck fermentation... again...

[Panoramix]

Hi all, still on BIAB level, I've been trying a nice recipe for pale ale.
I m doing full boil (50l stainless keg) BIAB, 1l starter from smack pack. Wyeast 1056
2kg pale ale 2row, 1.5 pilsner 2 row, 1 kg Munich malt, 0,75 crystal.
Hit my mash spot on, 68 for 1 hours. Mash out at 75 for 10 mins.
Pre boil G 1043 - post boil 1048 - right on target happy days!
I'm cooling with a chiller, decent time, straight in a chest freezer with temperature controller setup on 20degrees.
Brewed 11 feb 1048 - 15 feb 1028 - today 19 .. 1028!!!

My last batch was similar. I suspected not pouring the whole smack Pack in ... ( lesson learned shack well!) and also maybe lack of o2 .
This time whole smack pack in, and a nice force gushing in fermented thru wort pump and a bit of a shake... still a fail...
Any thought?

 

[damoninja]

That gravity ale stalled so low? Woah. Even low oxygen if you had a decent starter I'd have expected it to go fine. What gravity was the starter?

Toss in some US-05, it's the same yeast anyway.

 

[Panoramix]

80g DME in 800ml so about 1040 I think..

 

[Velu]

How did you measure 1.028? With a hydrometer or a refractometer? That's a shed load of crystal malt too.

 

[damoninja]

That's a shed load of crystal malt too.

I wouldn't say ~14-18 points worth.

What crystal did you use tho?

 

[Rocker1986]

It is a lot of crystal for a 20 odd litre sized batch but it won't cause it to stall that high. Does the beer taste overly sweet, like it normally would with that high of a gravity?

I'm guessing either the mash temp measurement was inaccurate and it was actually mashed higher than 68C, the yeast weren't in a very healthy state for some reason or a refractometer was used to measure the SG of the fermented samples and not adjusted for alcohol content.

 

[Panoramix]

I'm using a refractometer.
Hmmm, dunno about the crystal. I asked for a 10l caramel or crystal malt when I asked for my grain bill.. (brewmart) ..
That mean it could just be unfermentable?

 

[Panoramix]

a refractometer was used to measure the SG of the fermented samples and not adjusted for alcohol content.

[emoji15][emoji15][emoji15]

Ohhh.... ok I'm missing something here ....

 

[Panoramix]

Ok, Rocker1986 i love you!!
I just discover that i indeed need to convert my gravity reading post fermentation... !!!! Looks like I'm at 1015...
Thanks guys!

 

[malt junkie]

next time try and get that Crystal down around 5% of your total grain bill

 

[Rocker1986]

1.015 sounds more like it. No worries mate. I'd be looking to reduce the crystal too. It will contribute unfermentable sugars although possibly less of them when mashed with base malts compared to steeping it on its own.

 

[Danscraftbeer]

Try Mashing lower temp next time. Say 64c. Get a hydrometer as well if you don't have one. Also check on your yeast count too with yeast calculators like http://www.mrmalty.com/calc/calc.html ,check date of the yeast etc.
Its common that one packet wasn't enough unless you let the starter fully brew out to build up the yeast count.
A quick guess on your yeast date MrMalty recommends 2 packets with a 2lt starter to get up the numbers of cells needed.
Just some fine tuning on your brewing.

 

[fdsaasdf]

I haven't used Wyeast 1056 so can't speak for it but personally I don't bother with a starter unless I want to harvest the yeast.

Just to add my experience with fermentability mashing at 66.7 I've made a number of IPAs (including some red and brown) with 15-18% crystal malts that fermented out just fine with a single pack of US-05.

In ~1000L of all grain brewng I've not yet had a stuck ferment, fingers crossed I don't hit one soon...