2 Guinness batches that seem to be stuck

Hi,
So nearly two weeks ago (2/2) I brewed two 5 gal batches of Guinness clones back to back. One was a PM and the other one was an extract. They stopped bubbling pretty quickly and that bothered me so I decided to measure the gravity of the PM batch a week ago. I got 1.017. According to BeerSmith with a SG at 1.044 that gives me an ABV of 3.5% and 60% attenuation. I'm still a bit of a rookie brewer but I'm pretty sure thats bad. So I decided to swish the fermenter a bit to get the yeast going again and then checked the gravity again on saturday. Same gravity. This time I actually got a long spoon and stirred up the trub at the bottom of the bucket hoping to get something going. I hope this wasn't a bad idea. So today (over 72 hours later) I decided to check to gravity. Its at 1.0165. Its warmer in my room today than it was on Saturday so I'm pretty sure that makes up the minuscule laughable difference in the gravity. For the hell of it I decided to check my Extract Guinness batch and it has a gravity of 1.016. I'm not 100% of the SG cause I forgot it between brewing in the kitchen and making it back upstairs to write it down. I thought it was 1.053 but Beersmith says its supposed to be 1.045 so I'm compromising at 1.048. That gives me a 4.2% beer with 65% attenuation. Still pretty bad. BTW, for the PM I used Wyeast 1084 Irish Ale. For the Extract I used Nottinghams yeast. I did not use a starter for either of these. I probably should have with the Nottinghams yeast but I figured the Wyeast package is pretty much a starter itself so why bother.

Now, taken into account the situation I have described above I believe I have two options.
1. Accept the fact that I'll be drinking low alcohol probably sweet Irish Stout on St. Pattys day. (Barely an option)
2. Use my second Wyeast 1084 package I have to make a giant starter and split that starter between the two buckets and hope that they get to work.

One other thing I considered is that I might have caramelized some of the sugars making them unfermentable. However, my stove could barely keep both pots going at a boil, I find it hard to believe that they could have scorched my wort. I suppose if this is the case I could try boiling some water and DME and adding them to the buckets in hopes that yeast will eat it and raise the ABV. Then again I could just add some vodka to get the same effect.

Anyone got any thoughts on this?

It is a little hard to say with out seeing the recipes, some ingredients are more fermentable than others. but I would say stop messing with them and bottle them, they are really not that far off from the style, just pay a little attention to the fermentability of your ingredients and yeast pitching rates of future batches.

Some details that might help us come up with a more specific answer would be: how did you conduct the mash on the PM version (mash length, temp and mash out etc.), what sort of malt extract did you use and how old was it, when in the boil did you add the extract, etc, etc.

cheers,
John

For the PM I mashed the following at 152 for 60 min
2lb Flaked Barley
2lb Pale Malt
.75lb Roasted Barley
.25lb Black Barley
I then added 2lb of Light DME after the mash.

For my Extract Recipe
I steeped the following in 150 water for 30 min:
.75lb Roasted Barley
.25lb Acid Malt
.25lb Flaked Barley
.25lb Caramel 60L

Then I added 5lbs Light DME

All of these Ingredients were very fresh. None of the bags were opened or anything. I'd prefer to not cut my losses so quickly. I keg my beer anyway so as long as I can get my FG down before March I'll be fine.

It looks like they ought to ferment a little lower than that, but at the same time you had yeast that got of to a healthy start and stopped at the same gravity. I would leave them alone and just hold off another week or two on cold crashing and kegging. with beers this low in gravity you risk noticeable oxidation and infection more than you would with a higher gravity beer, so I would ovoid more stirring and swirling.

If you want to go ahead and add more yeast, although unless you did something (like a sudden large temp change) during active fermentation that could have caused the yeast to poop out it is most likely just going to be a waste of an $8 smack pack.

I would just make a starter with the yeast you have left and brew another beer with a third recipe, or add some boiled DME in a small volume if having a higher ABV is real important to you.

For what it is worth i would drink those beers the way they are, 60% attenuation is just a number not a bad or good thing in and of its self. Guinness draught is actually 4% so you are in the ball park for a clone on both batches right now.

I cant imagine a large temperature change although my roommate does complain if the room gets slightly warm and opens a bunch of the windows. How much of a change are we talking about? I doubt it would change more than a few degrees over an hour.

I'm also worried about how sweet the remaining beer would be. I think I might try to add more yeast but I'll look for a second opinion. I forgot that I have some SA-05 lying around that I could use. Maybe I'll try that

bump for second opinions

Only thought is; did it get cold?

The lowest I think it could have gone would be 65. Most of the time it was at 70. It probably wouldnt have even been rapid. I personally think it stayed at 70 +/- 2 the whole time. Would that be enough of a change to stall fermentation?

Notty is good down to below 60. I don't know about 1084, but it will be fine to at least 65; probably 60.

Assuming the Notty pack was fine, you would have at least pitched a correct amount wit the dry pack.

jhorgan1 said:

This time I actually got a long spoon and stirred up the trub at the bottom of the bucket hoping to get something going. I hope this wasn't a bad idea.

Click to expand...

It usually is.

BTW, SG = specific gravity, and is the measurement EACH time you measure.
The beginning gravity is called ORIGINAL, not starting, and the ending gravity is called FINAL. Each specified by saying OG and FG.

I did Yooper's stout recipe, and I ended up with about a 1.019 or so. The advice I got was not to stress out about it because there are a lot of nonfermentables in it. I tried waming it up after a little swirl/stir, but it only got me 1 gravity point. I'm thinking you've gotten all you're going to get out of that fermentation. I wouldn't bother with more yeast.

BTW, my beer is coming along very nicely. I'm sure your beer will do well also.

Well I decided to make a yeast starter and try it out anyway. I just pitched it 5 minutes ago. I'm gonna keg one of them on Sunday and then keg the second one a few days later. I'll report back then to say if the starter made a difference with the SG. I really hope I didn't oxidize this beer too much. My roommates chipped in the ingredients. I would hate to disappoint them.

So tonight I kegged the first batch and the FG didn't change at all still at 1.016. You win this time HBT. This batch was the one with a higher SG so its not the end of the world. I still get a 4.2% beer. That gives me 65.6% apparent attenuation and 53.3% real attenuation. Which is the attenuation that most people refer to? The real nail-biter is how my other beer worked out. If nothing happened then I'm stuck with a 3.2% beer. I'll have to call it "Marathon Guinness" since I'll start drinking at 10am and will continue to do so all day.