Stuck Fermentation (1st AG)

[Piperlester]

We did our first AG BIAB a couple weeks ago (2 weeks this past Sunday), fermentation happened quickly and then the heater kicked out a couple days in and the temp dropped down to around 14C (US-05 likes 18C+). To see where it was at, I checked the gravity and got 1.030, way too low for this recipe.

After getting the temperature issue fixed and the temp raised up to around 19C, I stirred the sediment with a sanitized spoon. This would have been last Sunday or Monday (1 week in). To help make the yeast a little happier, I upped the temp to around 24C (slowly climbed up over a couple days). After waiting until late Wednesday, there was no movement in the gravity or signs of fermentation, so I dry-pitched another packet of US-05.

Fast forward to Saturday morning, still no signs of life and the gravity is holding at 1.030. I made a US-05 starter (1.040 with light DME), pitched and let it ferment for 24 hours. At high krausen (or close to it) I pitched the entire starter and as much of the yeast cake that would stir up with swirling.

We're just over 24 hours later and still no signs of activity (haven't taken another gravity yet), but it isn't looking promising. My only ideas are some beano (not really the route I want to take, since it'll change the taste quite a bit) or do another brew, ferment and if all is well, rack the 2nd beer to secondary and then rack this stuck batch onto the yeast cake and stir it up again.

Any suggestions? I'm at a loss but the beer's not really pleasing in it's current state (about 2.5% and very sweet).

Here's the receipe from Brewers Friend:
Title: Easy Pale Ale

Brew Method: All Grain
Style Name: American Pale Ale
Boil Time: 60 min
Batch Size: 5.5 gallons (fermentor volume)
Boil Size: 7.5 gallons
Boil Gravity: 1.041

STATS: (According to Recipe)
Original Gravity: 1.056
Final Gravity: 1.013
ABV (standard): 5.64%
IBU (tinseth): 34.83
SRM (morey): 9.28

FERMENTABLES:
9 lb - American - Pale 2-Row (81.8%)
1 lb - American - White Wheat (9.1%)
1 lb - American - Caramel / Crystal 60L (9.1%)

HOPS:
1 oz - Cascade, Type: Pellet, AA: 7, Use: Boil for 60 min, IBU: 26.3
0.5 oz - Cascade, Type: Pellet, AA: 7, Use: Boil for 20 min, IBU: 7.96
0.5 oz - Cascade, Type: Pellet, AA: 7, Use: Boil for 1 min, IBU: 0.57

MASH GUIDELINES:
1) Infusion, Temp: 149 F, Time: 60 min
Starting Mash Thickness: 1.5 qt/lb

YEAST:
Safale S-05
Starter: No
Form: Dry

NOTES:
We mashed a little warm (between 149 and 155F), but in the last 25 minutes or so the temp climbed up due to a slight over-adjustment of the gas supply. Our efficiency was quite low, 60% IIRC, but with our boil off we ended up with a lower post-boil volume and hit the target gravity of 1.056 (4.75G of wort).

 

[EarthwormJim]

Are you measuring the gravity with a hydrometer or refractometer? After fermentation, when alcohol is present, the refract reading will need to be adjusted.

I plugged your numbers into Brewers Freinds caculator and the corrected reading was 1.013, so if you are using a refract, it is probably done. The sweetness could be coming from the caramel.

 

[Piperlester]

Are you measuring the gravity with a hydrometer or refractometer? After fermentation, when alcohol is present, the refract reading will need to be adjusted.

I plugged your numbers into Brewers Freinds caculator and the corrected reading was 1.013, so if you are using a refract, it is probably done. The sweetness could be coming from the caramel.

Measured using a hydrometer; the refractometer is stuck in the mail .

 

[kh54s10]

I can't see anything that would cause it to stall, even temperatures. Raising the temperature and swirling alone should have restarted it. The addition of more yeast certainly should. 24 hours is to early do decide that it is not working. The stress of being pitched on alcohol may have slowed it some.

I have no other suggestions but to give it a little more time and hope.

I am assuming your hydrometer is accurate since you describe it as too sweet. But worth checking it to be sure.

 

[BigCrazyAl]

When you say "between 149 and 155," that's almost the full target range for most home brews. 155+ will get you a less fermentable wort which can end high like yours did. Additionally, if you let it climb high enough, the enzymes could have been neutralized causing conversion to be incomplete.

 

[Pappers_]

When you say "between 149 and 155," that's almost the full target range for most home brews. 155+ will get you a less fermentable wort which can end high like yours did. Additionally, if you let it climb high enough, the enzymes could have been neutralized causing conversion to be incomplete.

This is likely your issue. If so, nothing to be done about it.

 

[RM-MN]

We did our first AG BIAB a couple weeks ago (2 weeks this past Sunday), fermentation happened quickly and then the heater kicked out a couple days in and the temp dropped down to around 14C (US-05 likes 18C+). To see where it was at, I checked the gravity and got 1.030, way too low for this recipe.

After getting the temperature issue fixed and the temp raised up to around 19C, I stirred the sediment with a sanitized spoon. This would have been last Sunday or Monday (1 week in). To help make the yeast a little happier, I upped the temp to around 24C (slowly climbed up over a couple days). After waiting until late Wednesday, there was no movement in the gravity or signs of fermentation, so I dry-pitched another packet of US-05.

Fast forward to Saturday morning, still no signs of life and the gravity is holding at 1.030. I made a US-05 starter (1.040 with light DME), pitched and let it ferment for 24 hours. At high krausen (or close to it) I pitched the entire starter and as much of the yeast cake that would stir up with swirling.

We're just over 24 hours later and still no signs of activity (haven't taken another gravity yet), but it isn't looking promising. My only ideas are some beano (not really the route I want to take, since it'll change the taste quite a bit) or do another brew, ferment and if all is well, rack the 2nd beer to secondary and then rack this stuck batch onto the yeast cake and stir it up again.

Any suggestions? I'm at a loss but the beer's not really pleasing in it's current state (about 2.5% and very sweet).

Here's the receipe from Brewers Friend:
Title: Easy Pale Ale

Brew Method: All Grain
Style Name: American Pale Ale
Boil Time: 60 min
Batch Size: 5.5 gallons (fermentor volume)
Boil Size: 7.5 gallons
Boil Gravity: 1.041

STATS: (According to Recipe)
Original Gravity: 1.056
Final Gravity: 1.013
ABV (standard): 5.64%
IBU (tinseth): 34.83
SRM (morey): 9.28

FERMENTABLES:
9 lb - American - Pale 2-Row (81.8%)
1 lb - American - White Wheat (9.1%)
1 lb - American - Caramel / Crystal 60L (9.1%)

HOPS:
1 oz - Cascade, Type: Pellet, AA: 7, Use: Boil for 60 min, IBU: 26.3
0.5 oz - Cascade, Type: Pellet, AA: 7, Use: Boil for 20 min, IBU: 7.96
0.5 oz - Cascade, Type: Pellet, AA: 7, Use: Boil for 1 min, IBU: 0.57

MASH GUIDELINES:
1) Infusion, Temp: 149 F, Time: 60 min
Starting Mash Thickness: 1.5 qt/lb

YEAST:
Safale S-05
Starter: No
Form: Dry

NOTES:
We mashed a little warm (between 149 and 155F), but in the last 25 minutes or so the temp climbed up due to a slight over-adjustment of the gas supply. Our efficiency was quite low, 60% IIRC, but with our boil off we ended up with a lower post-boil volume and hit the target gravity of 1.056 (4.75G of wort).

The highlighted wheat is probably mostly to blame for the lower efficiency but the adding heat could be the another factor. Adding heat during the mash is tricky because the mash needs to be stirred constantly and vigorously to keep the bottom of the mash from getting too hot and denaturing the enzymes during the long mash period needed to convert the wheat malt that likely isn't crushed all that well. You probably created a very unfermentable wort and are now at its final gravity.

For your next brew, choose a recipe that does not include wheat or rye. Unless you own the mill it won't be set to crush these smaller and harder kernels well enough. Ask for your grain to be double milled as this can aid the speed and amount of conversion. Bring your water to the calculated strike temperature and turn off the heat. Stir in the milled grains quickly, then cover and insulate. Do not add heat until the bag of grains is removed.

 

[kh54s10]

I looked at the raise in mash temperature and thought that since the really high temperatures were in the last 25 minutes, most of the conversion had already happened, so I didn't attribute that to much of a problem.

But if no other culprit is found that must be the source.

 

[Piperlester]

Thanks all - I'll check gravity again tonight and if no change, I'll get 'er kegged up this weekend... it's still beer. I'll call it "sessionable".