Escape from Stuck Fermentation Mountain - AE to the Rescue!

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Oatmeal Stout, mashed way to high (160s).
OG=1.063. FG = 1.032. Ouch. This after 2 weeks fermentation.

I pulled a test jar and added amylase enzymes. 1/4 tsp. Test jar sat at room temp. Here's how that turned out:

December 11, before enzymes:
AE_1_032.JPG


December 13, 2 days after enzymes added
AE_1_020.JPG


December 18, 7 days after enzymes added; pen added to increase volume of test jar so hydrometer would float
AE_1_012.JPG


Today (December 20), the gravity is still 1.012.
 
This would have probably finished much lower if not for the oatmeal and lactose that were in the recipe. So, I wouldn't recommend this unless your mash is hopelessly stuck at a cloying level. This beer might still turn out a disappointment. Will know in January. I probably won't bottle until January.

Here's the recipe in case anyone cares:

Ingredients
Amount Item Type % or IBU
18.00 lb Pale Malt, Maris Otter (3.0 SRM) Grain 67.29 %
3.00 lb Oats, Flaked (1.3 SRM) Grain 11.21 %
1.50 lb Carafa III (525.0 SRM) Grain 5.61 %
1.50 lb Caramunich Malt (56.0 SRM) Grain 5.61 %
1.00 lb SB Victory Malt (28.0 SRM) Grain 3.74 %
0.75 lb Chocolate Malt (450.0 SRM) Grain 2.80 %
1.00 oz Magnum [14.00 %] (90 min) (First Wort Hop) Hops 21.7 IBU
2.00 oz Northern Brewer [8.50 %] (30 min) Hops 17.2 IBU
2.00 items Whirlfloc Tablet (Boil 15.0 min) Misc
1.00 lb Milk Sugar (Lactose) (0.0 SRM) Sugar 3.74 %
2 Pkgs Saflager Dry Lager (Fermentis #S-23) Yeast-Lager
 
But how did it taste at 1.032? Too many people get worked up over numbers. I bet your gravity had as much to do with the fact that your base malt was only 2/3rds of the grist.
 
But how did it taste at 1.032? Too many people get worked up over numbers. I bet your gravity had as much to do with the fact that your base malt was only 2/3rds of the grist.

I doubt this. MO has enough diastatic power to convert 40 or 50% adjuncts and specialty grains. Mashing in the 160s denatures beta amylase in under 15 minutes and alpha doesn't survive too much longer unless it's thicker than 1 qt/lb, so he was stuck with a ton of longer sugars and starches. Plus he's got a few points added to his FG from the pound of lactose. You could mash in 100% 6-row at 162* and you wouldn't have much better attenuation.
 
Quick update on this, I added 2 tsp of AE to a carboy of this stout. The carboy was at about 1.030 when added (it was stable at this gravity). After a few days, it was down to 1.022 and stable. Based on my test jar, I expected it to drop further, but it didn't, and I'm glad for it.

I'm not sure if enzymes are "expended" in the process of catalyzing starch to fermentable sugars. I would have thought not, but the evidence seems to indicate that I didn't add enough to the carboy in order to get the attenuation that I got in the test jar.

I hope it was finished because I have it at 32F now and will be bottling on new years.
 
Quick update on this, I added 2 tsp of AE to a carboy of this stout. The carboy was at about 1.030 when added (it was stable at this gravity). After a few days, it was down to 1.022 and stable. Based on my test jar, I expected it to drop further, but it didn't, and I'm glad for it.

I'm not sure if enzymes are "expended" in the process of catalyzing starch to fermentable sugars. I would have thought not, but the evidence seems to indicate that I didn't add enough to the carboy in order to get the attenuation that I got in the test jar.

I hope it was finished because I have it at 32F now and will be bottling on new years.

I was redirected to this thread

https://www.homebrewtalk.com/f163/stuck-fermentation-know-options-just-need-advice-215098/#post2517628

I am in the same boat, though an IPA stuck at 1.030. Getting ready to add 2 tsp of AE.

Do i just sprinkle it in or stir it up in any way?
 
AE has saved me a few times. everyone should have it on hand. Usually if I miss my temp that high I'll wait till it drops where I want it and add the AE directly to the mash, this has worked out great too.
 
AE has saved me a few times. everyone should have it on hand. Usually if I miss my temp that high I'll wait till it drops where I want it and add the AE directly to the mash, this has worked out great too.

That's a great idea.
 
I added some AE to two stuck beers two days ago. Havent taken gravity readings yet but theres plenty of airlock activity and active yeast floating around. Are there any potential risks or downsides to doing this? It just seems too good to be true.
 
I've been trying to make beers out of crazy ingredients (like 100% quinoa) and have tried using alpha amylase in the mash, though it didn't seem to do much.

Reading this page in How to Brew I thought the enzymes needed higher temps to be active. But from what you all are saying it sounds like it can convert starch to sugar at room temp...
 
no I believe whats it is doing in the primary fermenter is eating the residual sugars(and possibly longer strands?) the the yeast either pooped out on or simply cannot consume.

In the mash it does convert the starches for you, so if you kill your enzymes with too high of a mash you can add them back when the temp comes down.

The most widely anecdotal downside is getting it to stop ffermenting, ie it'll dry the beer out too much. I have not had this problem and I have added it to a primary twice. IIRC it just upped my attenuation about 10 perenctage points or so.

Of course I am no expert but this is how I understand it, and it has worked this way for me, i love the stuff.
 
Yep

Off an running today. Do I need to kill this after 2 days or so or just let it run its course. looking to finish at 1.018

All I know is documented in this thread. I did not stop it in any way (which would require bringing the beer to 170 for a while, I guess).

My beer is really nice. I have no complaints and I would do it again in the same situation.
 
Oatmeal Stout, mashed way to high (160s).
OG=1.063. FG = 1.032. Ouch. This after 2 weeks fermentation.

I pulled a test jar and added amylase enzymes. 1/4 tsp. Test jar sat at room temp. Here's how that turned out:

December 11, before enzymes:
AE_1_032.JPG


December 13, 2 days after enzymes added
AE_1_020.JPG


December 18, 7 days after enzymes added; pen added to increase volume of test jar so hydrometer would float
AE_1_012.JPG


Today (December 20), the gravity is still 1.012.

I know it's an old one but this should be a sticky. Great post. Great info. I've not needed to do this but if and when i do I would want to reference this thread. Tasty looking beer to boot.
 
I know it's an old one but this should be a sticky. Great post. Great info. I've not needed to do this but if and when i do I would want to reference this thread. Tasty looking beer to boot.

Thanks Gavin. I only used it that one time. I've been meaning to make a light lager by adding enzymes, but haven't done that yet.

So, I don't have enough experience with it to say it's the ultimate solution for poor attenuation in the fermentor. I would not hesitate to use it again myself, and as you can see I recommend others try it if their beer is hopelessly stuck. If they do, I hope they would come back and add to our knowledgebase as I did here.
 
Yeah, the stuff definitely works. I had a barleywine finish WAY to high. Tried to stir and warm it up, nothing, added active yeast, nothing, added amylase enzyme and it worked a treat. Would definitely be nice to have some clearer numbers on how much to add to what volume of beer to get a certain predictable result. Unfortunately, for a long time, people were too quick to lump amylase enzyme in with Beano and would just simply wag their finger and explain how it was going to ferment your beer down to a sub one gravity.

In the end, it's a good tool to have. Not the right one for every situation, but good to know about when its use may be warranted.
 
Yeah, the stuff definitely works. I had a barleywine finish WAY to high. Tried to stir and warm it up, nothing, added active yeast, nothing, added amylase enzyme and it worked a treat. Would definitely be nice to have some clearer numbers on how much to add to what volume of beer to get a certain predictable result. Unfortunately, for a long time, people were too quick to lump amylase enzyme in with Beano and would just simply wag their finger and explain how it was going to ferment your beer down to a sub one gravity.

In the end, it's a good tool to have. Not the right one for every situation, but good to know about when its use may be warranted.

Right. Just so it's clear to anyone coming into this thread, nobody should use Beano in beer. It's a different enzyme than amylase (it's galactinase or something like that) and goes through the wort like Sherman through the south.
 
Honestly, adding that pen in the hydro is my takeaway from this thread. I cant tell you how many times the hydrometer refuses to float upright in the middle....
 
I know this is like 5 years old, but someone else brought it back up so I'll make some observations :D

Given
-Test Jar (assuming 1 quart): 0.25 tsp AE added, 20 point drop
-5 gallon carboy (20 quarts): 2 tsp AE added, 8 point drop (2 tsp / 20 quarts = 0.1 tsp per quart)

Using this as your guide, 0.25 tsp into a quart sample is 2.5x the point drop (8 points in this case) which gives us a total of 20 points dropped, which coincides perfectly with your test jar (assuming it was about a quart in volume). Obviously, this is a single data point and overly simplistic, but if it could serve as a base from which to work it might be a nice starting point.

So, passedpawn, do you remember the test jar sample size you hit with the 0.25tsp AE?
 
I am going to go through my notes as well, the batch I used it on was several years ago. I think it was actually an old ale now that I think about it. I think I wrote down how much I added to the fermenter, should have been six gallons of beer. I know that I was hoping to come down almost twenty points. The amount I added pulled it down ten and I decided not to mess with it anymore. It ended up being slightly sweet still, but MUCH better than it was originally.
 
That test jar holds about exactly 3/4 cup (6 oz) when floating a hydrometer.

HOWEVER, enzymes are not consumed in reactions. They are a catalyst. So I don't think the amount matters too much. If you add AE, the wort ferments to the limit of attenuation. That's probably between 80 and 85%. That's a little too far for some beers, but if you started with a big beer (i.e., 1.067 or higher) and you get 85% attenuation, you're still above 1.010. That's very drinkable, though maybe not the target.

My youngest boy is organic chem whiz. He explained this all to me last year, something about enzymes and puzzle pieces fitting together, but I forget. Wish he was home but he's at college.
 
I've now seen two more threads in the last week since first seeing this where this thread would have been of use to the OP.

Can this thread be stickied by a mod as I'm sure @passedpawn is reluctant to sticky his own thread.

I'm only one voice in the crowd so perhaps others will disagree.


Please Sticky the thread and delete this post.
 
Thought I would drop these two links here to Kai Troester's site. He's done a lot of the legwork for us. Thanks Kai.

I concluded 85-90% attenuation from alpha amylase at low temperatures by extrapolating the data available at the following two places on his site. If I find additional information, I'll post. Seems like such an easy thing to test, and I guess I did here in this thread, but a much better experiment would be useful.

The Theory of Mashing > Starch conversion enzymes
Effect of mashing conditions > Temperature and Time
 
Thought I would drop these two links here to Kai Troester's site. He's done a lot of the legwork for us. Thanks Kai.

I concluded 85-90% attenuation from alpha amylase at low temperatures by extrapolating the data available at the following two places on his site. If I find additional information, I'll post. Seems like such an easy thing to test, and I guess I did here in this thread, but a much better experiment would be useful.

The Theory of Mashing > Starch conversion enzymes
Effect of mashing conditions > Temperature and Time


thanks. 85-90% attenuation is much closer to what i have experienced myself over several trials. when you stated that it would not stop i was curious as to why my results have been different
 
https://www.homebrewtalk.com/showpost.php?p=7220058&postcount=44

i hadnt heard of limit of fermentation before i wanted to learn more about it. thats why i asked to for references. no need to get defensive

Just trying to understand what you're talking about. Can you see why I'm asking?

The only way to stop it is to kill the yeast. You'll need heat to do that.

It'll keep fermenting to the limit of fermentation, which is about 85% of the OG. For you, that's 1.012.

thanks. 85-90% attenuation is much closer to what i have experienced myself over several trials. when you stated that it would not stop i was curious as to why my results have been different
 
Ok. I'm on the band wagon. Four weeks ago, I did an ipa which finished much higher than expected- 1.080. Used wlp008 with a healthy starter. Got about 72% attenuation so it's down to 1.023. It's done. (It was actually at 1.030 about a week and a half ago. So I tried to rouse, warmed it up to 71*.... That's what actually got me to where I am today).
I Just added about 1.75 tsp AE. We'll see what happens.
Thanks for the information on this thread. It gave me the confidence to try to turn this beer into something drinkable. I will post back.
 
I'm going to go out on a limb and say that sulphites stink and that I don't like wines that contain sorbate, but it's not like they put ingredients on real wine bottles.

Would maltose be broken down by A.E. or does it depend the type?

In other news, the Doctor ok'd the sampling of my last batch of Amorita's American-Belgian (M.O.base 1.5%sm, +10% honey ), but I think it turned out in the 1.080-1.005(7) (couldn't read through the Krausties). Warrior(b)/Glacier(hs+2013) Glacier(dry2014).

I brought in two bombers to work today.. not like I'm driving home but there will be plenty of people to give sips to...
 
Thought I would drop these two links here to Kai Troester's site. He's done a lot of the legwork for us. Thanks Kai.

I concluded 85-90% attenuation from alpha amylase at low temperatures by extrapolating the data available at the following two places on his site. If I find additional information, I'll post. Seems like such an easy thing to test, and I guess I did here in this thread, but a much better experiment would be useful.

The Theory of Mashing > Starch conversion enzymes
Effect of mashing conditions > Temperature and Time

Makes me want to try a cold brew mash. Just gargle some starsan before drinking. Seriously though, You'd think you could dominate the natural flaura by using an ultra low temp Sac. or other and strictly controlling the temps?
 
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