Done or stuck?

[DrewBlue]

I've had an extract Old Ale in primary for three weeks. Starting at 1.080, I was expecting a FG of 1.020-1.023 based on this yeast (Wyeast 1318). A week ago it was at 1.030. At that time I roused the yeast, bundled it up, and turned the heat up a couple degrees. I checked tonight and it's still only down to 1.029.

At this point I realize that I probably underpitched :smack: (I used two smack packs and should have done 3; yes, I know, I know I need to start doing starters and intend to learn after this experience). I had an insanely vigorous fermentation for the first 2-3 days (the blowoff tube was overwhelmed; krausen was belching into the blowoff bucket, and then it slowed considerably).

It seems like everyone on these types of threads wants to know about the sugars in the recipe, so I used: extra light DME, 4 oz. of treacle, and 8 oz. of Maltodextrin. Any other minimal sugars came from 1.25 lb. steeping grains. I hit my expected OG, and oxygenated really well prior to pitching. Temperatures were steady throughout fermentation and within the recommended range for the yeast. The samples taste good, so I don't think it's infected.

In retrospect, when I cleaned the blowoff bucket, there was a lot of yeast sediment in the bottom. Maybe it blew off a lot of what it still needed to finish?

The beer is not very clear considering how long it has been in the fermentor, and I thought this was a very flocculent yeast. There is still some CO2 bubbling (about 1x a minute or so; but I know that shouldn't mean anything).

At any rate, I'm .006 from hitting my calculated low end FG for this yeast, and .009 from the high end FG. I don't have the means to keg, and I don't want bottle bombs...

SO, should I :
1) Not worry about it and bottle?
2) Leave it alone for another week? (worried about off flavors)
3) Add amylase enzyme? (I've read of success with this)
4) or try to do my first yeast starter and pitch it?

I really appreciate any help anyone can provide. If I left anything out, feel free to ask. I just don't want to do anything extreme if I'm worrying about nothing. But if something needs to be done, it seems like it's time to act.

 

[sfgoat]

I would probably give it another week and see if it is still at the same sg . If so just bottle and roll with it.

 

[F_R_O_G]

do a force fermentation test if you really want to know whats going on. or just leave it and crank the heat up to 77ish

 

[Denny]

Extract beers often finish higher than predicted due to the way the extract is produced. In addition, the attenuation rating of the yeast is not necessarily a way of predicting your attenuation. It's for comparing one yeast to another using a standardized wort. The fermentability of your own wort is what determines attenuation. The suggestion for a forced fermentation test is good.

 

[DrewBlue]

The fermentability of your own wort is what determines attenuation. The suggestion for a forced fermentation test is good.

So if the wort, not the yeast determine the degree to which it is fermentable, can I do a forced fermentation test with any brewing yeast, or do I have to use the same yeast i used for fermentation?

 

[Denny]

So if the wort, not the yeast determine the degree to which it is fermentable, can I do a forced fermentation test with any brewing yeast, or do I have to use the same yeast i used for fermentation?

ANY yeast is fine, even bread yeast. Use a lot of it. You want to find out how far the wort will ferment.

 

[DrewBlue]

Ah, I see. I found another post that said I can use any yeast with the goal of fully attenuating the sample, and then I can compare that vs. the attenuation percentage range on the type of yeast I used.

In other words, the lowest my wort will go being 100%, and then calculating back from there. Does that sound like a good approach?

 

[Denny]

Ah, I see. I found another post that said I can use any yeast with the goal of fully attenuating the sample, and then I can compare that vs. the attenuation percentage range on the type of yeast I used.

In other words, the lowest my wort will go being 100%, and then calculating back from there. Does that sound like a good approach?

Yeah, that's basically the idea. Find out how fermentable the wort is, then apply the attenuation rating of the yeast you used to that.

 

[DrewBlue]

Okay, so I did the FFT, and I'm still confused...

Here's how I did it:
(Of course, sanitized everything), took a hydrometer sample (still at 1.029), transferred it to a pint-size mason jar, sprinkled a more than ample dose of both dry champagne yeast and baker's yeast, covered with foil and a rubber band, and then aerated (swirled). The next morning, the yeast had all settled, so I gave it another swirl. It settled again fairly quickly. Except for a few CO2 bubble clusters on the surface I saw little in the way of fermentation activity. The temperature was about 70º throughout.

Last night (after four days) I checked the gravity and it is UNCHANGED. I guess I expected that the gravity would at least go down a little.

So does this mean that my FFT failed? Or does it mean that it's as fermented as it is going to get, and I can now move on with my life?

 

[fixitoscar]

in my experience I could not get extract beers below 1.020 using starters, proper temp ramping agressive yeast strains ect. Bigger beers often finished higher than that. If you want your extract recipe to finish dryer you are going to have to substitute sugar for some of those gravity points.
I'm going to say after 3-4 weeks its done. There are ways to try to get it lower, but if it was me I would just bottle her up.

 

[Denny]

Okay, so I did the FFT, and I'm still confused...

Here's how I did it:
(Of course, sanitized everything), took a hydrometer sample (still at 1.029), transferred it to a pint-size mason jar, sprinkled a more than ample dose of both dry champagne yeast and baker's yeast, covered with foil and a rubber band, and then aerated (swirled). The next morning, the yeast had all settled, so I gave it another swirl. It settled again fairly quickly. Except for a few CO2 bubble clusters on the surface I saw little in the way of fermentation activity. The temperature was about 70º throughout.

Last night (after four days) I checked the gravity and it is UNCHANGED. I guess I expected that the gravity would at least go down a little.

So does this mean that my FFT failed? Or does it mean that it's as fermented as it is going to get, and I can now move on with my life?

You got one of the 2 possible results and it indicates that there are no fermentables left in your beer. It's done.

 

[DrewBlue]

I'm going to say after 3-4 weeks its done. There are ways to try to get it lower, but if it was me I would just bottle her up.

At this point I'm inclined to do that, too. I'm looking forward to doing FFTs on my future brews though, so that was good experience. Thanks to all of you for the helpful guidance!

 

[DrewBlue]

Just an update in case anyone stumbles upon this thread (because I hate when you're looking for info, and there is no followup and you're just left in suspense as to the outcome). It turned out great. It's now been in the bottle for seven months and no bottle bombs (carb is just right). The only issue is that the ABV isn't as high as I was aiming for, but it's still great.