Possible stuck fermentation. Need help.

I have 2 beers.

One IPA that I used Safale US-05 with a date of 6/2010. Brewed 6-5-2010. Mash temp 158* fr 60 minutes. Re-hydrated yeast with 1 1/2 cups water heated to 140*, added 1 tsp sugar and cooled to 70*, added yeast, kept covered about 20 minutes until pitching time. Pitching temp 68*.

Racked to 2ndary today. Checked gravity and it was 1.021 (OG was 1.062). Placed 2ndary in grain room at around 75-78 ambient to try and finish out.

Second beer, Rogue Dead Guy Ale clone. Brewed 2 days later on 6-7-10. Used PacMan yeast. Starter made 2 days prior. 1000ml. OG 1.064 and gravity today, 1.023. Went ahead and returned it to the fermentation freezer.

Both of these beers fermented at between 64-68 ambient. The IPA was a tad cloudy made with American 2 row and the Dead Guy Ale was Marris Otter and it was clear.

I checked the gravity with two hydrometers.

I also had a Bass that stopped at 1.022 (started at 1.060) 20 days later. Didn't realize it until after I kegged it that it hadn't finished out and it started back up in the keg with was at room temp (75ish). I used Windsor yeast on this one. Mashed at 150*.

Now looking over my notes, the Bass was the first brew on my new Brutus system with my new Blichmann pots. I am wondering if this has anything to do with the mash?? On my old keggle system I had my MT insulated and would let it sit the whole hour and it would drop maybe 2 degrees at the most. With this system, no insulation and I am direct firing my mash while recirculating from the bottom back into the top.

Three brews. Three different yeasts. Only constant is the new system. I have never had this happen before.

What was the batch size and what was the yeast pitch rate?

All 5 gallons. Fry yeast one packet each (Windsor and US-05) and Pacman one smack pac added to starter.

It looks good, but I've had issues with the Dry yeasts "finishing early" with some of my higher gravity beers to 1.060 and above. I've started using two packages of dry per 5 gal batch and three per 10 gal. I may be skirting other issues but it has worked so far. That and spending 100's on temperature control of the fermentation!

Its hard to trouble shoot your problem as there are too many variables. 3 different yeasts, new brewing system and process, different recipes, different mash temperatures.

When I make major changes to my brewing set-up I intentionally rebrew the same recipe several times and take copious notes. Pick something cheap and easy like a bitter or scottish 60 or pale ale.

GT

Thanks guys. I forgot to mention that I had one other beer in this series that did ferment out right. Edworts Stone IPA Clone, OG 1.054-FG 1.012 at 3rd week when I racked to the 2ndary.

I think one of the recipes may have had to many specialty grains. Here's the recipe:
Rob's India Pale Ale
14-B American IPA
Author: Rob
Date: 6/5/10

Size: 6.0 gal
Efficiency: 78.0%
Attenuation: 67.0%
Calories: 210.69 kcal per 12.0 fl oz

Original Gravity: 1.062 (1.056 - 1.075)
Terminal Gravity: 1.021 (1.010 - 1.018)
Color: 12.09 (6.0 - 15.0)
Alcohol: 5.49% (5.5% - 7.5%)
Bitterness: 57.6 (40.0 - 70.0)

Ingredients:
10.0 lb American 2-row
1.0 lb Munich Malt
1.0 lb Crystal Malt 20°L
1.0 lb Cara-Pils® Malt
1.0 lb Honey Malt
6.2 oz Vienna Malt
1.0 oz Warrior (13.4%) - added during boil, boiled 60 min
1.0 oz Northern Brewer (10.8%) - added during boil, boiled 10 min
1.0 oz Fuggle (3.7%) - added during boil, boiled 5 min



Results generated by BeerTools Pro 1.5.10


On this beer I moved it to ambient 75 degree temps yesterday. checked it this morning and no activity. I had already moved it to the 2ndary before finding the gravity was too high. So this morning I added another packet of the 6/2010 US-05 straight to it (in a 5 gallon carboy...hope I don't get too much fermentation).

On the Rogue Dead Guy Ale Clone with the Pacman yeast I raised the temp to 75 also just now, and slowly and gently stirred the yeast back into suspension.

One thing I noticed in common after going over my notes again. I mashed at 158* and let the temp fall, on purpose to 150*. Then I brought it back to 158* and let it fall again. I did this on the IPA and the Rogue Clone.

I batch sparged the IPA and Fly sparged the Rogue.

On the Bass, I mashed at 150* constant (recirculated as I heated to maintain temp) and batched sparged.

158 is a pretty high mash temp, and will yield a pretty dextrinous wort that isn't as fermentable as a wort mashed at 150. I like it for the Dead Guy- as it's a malt bomb. I think I mash the DG at 156ish, but I mash IPAs at about 153.

With a mash temp of 158, the DG clone might just be done.

YooperBrew said:

158 is a pretty high mash temp, and will yield a pretty dextrinous wort that isn't as fermentable as a wort mashed at 150. I like it for the Dead Guy- as it's a malt bomb. I think I mash the DG at 156ish, but I mash IPAs at about 153.

With a mash temp of 158, the DG clone might just be done.

Click to expand...

Thanks Yoop. The one thing I noticed was that the IPA was still cloudy after three weeks and the DG was clear. Thats why I was puzzled on the DG. I will let it sit another week or two since I stirred it up and then check it again.

Just kegged this and it ended up finishing at 1.012. Thanks for all f your help.

Rogue Dead Guy Pale Pac Man yeast
10-B American Amber Ale
Author: Rob
Date: 6/7/10

Size: 6.0 gal
Efficiency: 79.0%
Attenuation: 81.0%
Calories: 210.9 kcal per 12.0 fl oz

Original Gravity: 1.064 (1.045 - 1.060)
Terminal Gravity: 1.012 (1.010 - 1.015)
Color: 14.69 (10.0 - 17.0)
Alcohol: 6.79% (4.5% - 6.2%)
Bitterness: 34.6 (25.0 - 40.0)

Ingredients:
10.0 lb Maris Otter
19 oz Caramunich® TYPE I
25 oz Munich Malt
1.0 lb Crystal Malt 40°L
1.0 oz Perle (8.1%) - added during boil, boiled 60 min
.5 oz Perle (8.1%) - added during boil, boiled 20 min
.25 oz Perle (8.1%) - added during boil, boiled 5.0 min
.25 oz Sterling (6.0%) - added during boil, boiled 5.0 min



Results generated by BeerTools Pro 1.5.10

How did you get the Dead Guy to finish lower? Did it just restart and drop that much just from raising the temp?

I have a stout that isn't wanting to drop lower than 1.021 and I'm thinking about taking it upstairs where it's several degrees warmer, ambient temp.

*edit* my bad, i see - you warmed it up, swirled the yeast and dropped some us-05

hmm... wondering if this would work for me

Burgs,

Yes. I just gently stirred up the yeast from the bottom, raised the temp about 5 degrees and it finished out. I never saw any more signs of fermentation.

Did you just swirl it or actually stick a sanitized spoon in there?

And I thought I read that you pitched another pack of yeast, no?

I swirled my stout a few times and once more this morning - checked the temp and it's up 4 degrees from where it was downstairs, I'm hoping that helps to get it going again.

Thanks for the reply, I appreciate it!

Burgs said:

How did you get the Dead Guy to finish lower? Did it just restart and drop that much just from raising the temp?

I have a stout that isn't wanting to drop lower than 1.021 and I'm thinking about taking it upstairs where it's several degrees warmer, ambient temp.

*edit* my bad, i see - you warmed it up, swirled the yeast and dropped some us-05

hmm... wondering if this would work for me

Click to expand...

Decatur, Illinois, huh? I haven't been there in a LONG time.

Burgs said:

Did you just swirl it or actually stick a sanitized spoon in there?

And I thought I read that you pitched another pack of yeast, no?

I swirled my stout a few times and once more this morning - checked the temp and it's up 4 degrees from where it was downstairs, I'm hoping that helps to get it going again.

Thanks for the reply, I appreciate it!

Click to expand...

I sanitized a plastic spoon and carefully stirred the yeast up trying not to scrape the sides of the bucket so as not to get scratches in it.

I added yeast to a differnt batch. This one was done with Pac Man yeast and I didn't want to "contaminate" it with anything else.

Cool, thanks man.

Hey - sort of off-topic but your recipe for dead guy says 10-B American Amber Ale... is that its bjcp category? I've always hated the whole "maibock-style ale" description Rogue gives it because it makes no sense to me.

Burgs said:

Cool, thanks man.

Hey - sort of off-topic but your recipe for dead guy says 10-B American Amber Ale... is that its bjcp category? I've always hated the whole "maibock-style ale" description Rogue gives it because it makes no sense to me.

Click to expand...

If I had to guess I would say yes. The BTP software categorizes it as best suited to that style.

yooperbrew - 158 is a "pretty high" mash temp eh? so if i did my first partial extract with a mash tem of 165 cause i'm on a stovetop and wasn't careful about the temperature, that might be a reason for a stuck primary fermentation? thanks...

GermanBlood said:

yooperbrew - 158 is a "pretty high" mash temp eh? so if i did my first partial extract with a mash tem of 165 cause i'm on a stovetop and wasn't careful about the temperature, that might be a reason for a stuck primary fermentation? thanks...

Click to expand...

well it may not be stuck but instead out of fermentable sugars.

When you mash that high you get more unfermentables. Your beer may have fermented all it can and that is what you are left with.

I believe you can use some amylase enzyme to possibly bring that down but it works quite slowly and better at higher temps (not in a fridge / fermentation chamber).

In the future be very midful of temps. They are very important both in mashing / sparging as well as fermentation.

Thank you for the input. I will have to check at my LHBS for the amylase enzyme. Is what you are really suggesting is to add more malt extract, or to do another mash at 150 degrees? I had no idea that 15 degrees would make that big of a difference. I will be more careful next time. I do not use a fridge / fermentation chamber as the Pacific Northwest does not warrent that, even in the summer I can ferment at 68-73 all summer long.