Mashed too high: Add corn sugar to bring up ABV?

[djonesax]

I am pretty sure my Yooper's Oatmeal stout is done at FG 1.026 from an SG of 1.055. I must have mashed too high because I took a sample and added beano and it started fermenting again. I also added some DME to another sample and it also started fermenting again. I'm only at 11 days in primary, I did raise the temp and stir up the yeast so I'll see how that goes in the next few days, but my gut tells me this is done.

The beer tastes pretty good but I'm just not going to be pleased with a 3.8% ABV beer at 1.026 FG. If it is going to be sweet, I'd at least like the ABV to be closer to 5%.

I read that 1# of corn sugar per 5 gallons would raise the gravity by .009 points so I was considering adding 2lb of corn sugar to bring the ABV up to 5%. Mine is a 10 gallon batch.

Any thoughts?

David

 

[deepbluegroove]

Even if you mashed high you should have pretty high fermentability because of the two row that was in your recipe. It helps convert even at a higher mash temp. Anyhow 1.026 sounds pretty high.

You could use another yeast to dry it out. Not too dry otherwise its not a stout. Look for a yeast with your desired AA.

 

[rlmiller10]

I am pretty sure my Yooper's Oatmeal stout is done at FG 1.026 from an SG of 1.055. I must have mashed too high because I took a sample and added beano and it started fermenting again. I also added some DME to another sample and it also started fermenting again. I'm only at 11 days in primary, I did raise the temp and stir up the yeast so I'll see how that goes in the next few days, but my gut tells me this is done.

The beer tastes pretty good but I'm just not going to be pleased with a 3.8% ABV beer at 1.026 FG. If it is going to be sweet, I'd at least like the ABV to be closer to 5%.

I read that 1# of corn sugar per 5 gallons would raise the gravity by .009 points so I was considering adding 2lb of corn sugar to bring the ABV up to 5%. Mine is a 10 gallon batch.

Any thoughts?

David

Leave it as it is and put it on our cereal for breakfast.

 

[PGEduardo]

I would just take another reading in a few days and if it's stuck dump in the sugar like you planned. Sounds like your yeast is still plenty viable.

You might have to let it age a bit if the added sugar makes it a bit "hot" - although if you ferment low enough it might be possible to avoid this? I'd like to know this answer myself...

 

[55x11]

Leave it as it is and put it on our cereal for breakfast.

You can add sugar (or LME) or try to attenuate a bit more with another yeast. But some oatmeal stouts are not super-high in ABV, so it may be a nice mellow stout to enjoy over a few bottles. Have you tasted it yet?

 

[JLEEFELDMAN]

From what I have read the beans is going to work on it till all the sugars are gone. Probably should have put some amylase enzyme instead.

 

[djonesax]

From what I have read the beans is going to work on it till all the sugars are gone. Probably should have put some amylase enzyme instead.

I didnt put the beano in the fermenter, just in a sample to test to see if my problem was related to unfermentable sugars. I also added DME to another sample to see if the yeast were still viable and that fermented more as well. That's why i think I must have mashed too high.

it seems my yeast is fine, there is just nothing more to eat.

 

[djonesax]

You can add sugar (or LME) or try to attenuate a bit more with another yeast. But some oatmeal stouts are not super-high in ABV, so it may be a nice mellow stout to enjoy over a few bottles. Have you tasted it yet?

I have tasted it and it tastes pretty good, I just would prefer a 5% ABV.

Say I did add the sugar after another few days, does 2# sound about right?

Also what yeast would ferment the "unfermentables" so its just slightly lowe,r down to maybe 1.016-1.018?

David

 

[55x11]

I have tasted it and it tastes pretty good, I just would prefer a 5% ABV.

Say I did add the sugar after another few days, does 2# sound about right?

Also what yeast would ferment the "unfermentables" so its just slightly lowe,r down to maybe 1.016-1.018?

David

by my calculation 1lb of sugar in 5 Gallons should add 0.009 or so points, and increase ABV by 1.4% or so. So perhaps 1lb is enough. 2lbs of sugar will raise ABV by 2.7%.

I would probably go the sugar route first, maybe the yeast will restart itself once it has sugar and will reduce the gravity below 1.026 or whatever you got now.
Highly attenuating, clean yeast is probably your best choice. Maybe WLP-001? Maybe some dry yeast - even some champaign yeast will do? I am not sure. But I would add 1 lbs sugar and wait first. Oatmeal shouldn't be dry anyways and should have solid mouthfeel, if it's not super-sweet, I would leave it be.
I had a stout that just finished at 1.016 but overall is "only" 4%. But I like it, for a change (I tend to brew stronger beers usually, which means I cannot drink as many of them as I would like).

 

[djonesax]

by my calculation 1lb of sugar in 5 Gallons should add 0.009 or so points, and increase ABV by 1.4% or so. So perhaps 1lb is enough. 2lbs of sugar will raise ABV by 2.7%.

Its a 10 gallon batch which I why I thought 2 lbs.

I would probably go the sugar route first, maybe the yeast will restart itself once it has sugar and will reduce the gravity below 1.026 or whatever you got now.
Highly attenuating, clean yeast is probably your best choice. Maybe WLP-001? Maybe some dry yeast - even some champaign yeast will do? I am not sure. But I would add 1 lbs sugar and wait first. Oatmeal shouldn't be dry anyways and should have solid mouthfeel, if it's not super-sweet, I would leave it be.
I had a stout that just finished at 1.016 but overall is "only" 4%. But I like it, for a change (I tend to brew stronger beers usually, which means I cannot drink as many of them as I would like).

I'm going to let it go until Friday check the gravity again and then decide if I want to add some sugar.

 

[djonesax]

By the way the sample I added beano to took the gravity down to 1.014. The other sample with two table spoons of DME actually went up .002 or stayed about the same. The DME version tasted better and the beano was thinner with more black coffee flavor.

I'm tempted to split this batch into two buckets and add sugar to one and amylase to another just to see how they end up.

 

[55x11]

By the way the sample I added beano to took the gravity down to 1.014. The other sample with two table spoons of DME actually went up .002 or stayed about the same. The DME version tasted better and the beano was thinner with more black coffee flavor.

I'm tempted to split this batch into two buckets and add sugar to one and amylase to another just to see how they end up.

the way beano works is it uses enzymes and breaks down unfermentable complex sugars. So it's a bit like extra mashing or something. I would maybe try to do forced fermentation on a small sample by adding some yeast (if you have some) and see if gravity drops.

 

[djonesax]

the way beano works is it uses enzymes and breaks down unfermentable complex sugars. So it's a bit like extra mashing or something. I would maybe try to do forced fermentation on a small sample by adding some yeast (if you have some) and see if gravity drops.

Adding beano to the sample was my way of doing a forced fermentation. Since the gravity seemed stuck at 1.028, I added beano to the sample to see if the yeast were able to ferment more after the beano did its thing. That worked which seems to confirm that I had unfermentable sugars. I could be wrong but I dont think adding more yeast will help at this point, if the sugar I have they cant eat.

 

[55x11]

Adding beano to the sample was my way of doing a forced fermentation. Since the gravity seemed stuck at 1.028, I added beano to the sample to see if the yeast were able to ferment more after the beano did its thing. That worked which seems to confirm that I had unfermentable sugars. I could be wrong but I dont think adding more yeast will help at this point, if the sugar I have they cant eat.

but how do you know it's not just a stalled fermentation?

In other words, what if the effect is just adding yeast and it restarts fermentation, and beano effect is largely irrelevant?

I think forced fermentation would answer this question. If forced fermentation (no beano) can bring SG lower than 1.028, it means there are still fermentable sugars, and adding more yeast/new yeast can help you bring SG down.

There are always some unfermentable sugars so beano should have worked to some extent anyways.

 

[wzd]

...
I'm tempted to split this batch into two buckets and add sugar to one and amylase to another just to see how they end up.

Well if amylase or Beano dries it out too much, you could do it on a small portion, and play with blending. But you would need to have a way to inactivate the enzymes or they would go to work after blending!!

 

[djonesax]

but how do you know it's not just a stalled fermentation?

In other words, what if the effect is just adding yeast and it restarts fermentation, and beano effect is largely irrelevant?

I think forced fermentation would answer this question. If forced fermentation (no beano) can bring SG lower than 1.028, it means there are still fermentable sugars, and adding more yeast/new yeast can help you bring SG down.

There are always some unfermentable sugars so beano should have worked to some extent anyways.

Maybe I am missing something, so please pardon any ignorance on my part. I have been stuck at the same FG for many days now. I know my yeast are able to ferment for two reasons. One, I added DME to a sample I took from the fermenter and they fermented it. Two, I added the beano to a sample and it started fermenting again so it broke down what my current yeast couldn't eat and made it edible.

Given that, how could adding new yeast help? If there are still fermentable sugars in there, what would make new yeast be able to eat what my current yeast cant, keeping in mind that I have tested that my current yeast CAN eat the sugars that beano converted and the DME?

Thanks,

David

 

[djonesax]

Well if amylase or Beano dries it out too much, you could do it on a small portion, and play with blending. But you would need to have a way to inactivate the enzymes or they would go to work after blending!!

The only way I know to denature it is to heat it up but they work slower in the cold so if I add it maybe I'll just drink it fast

 

[55x11]

Maybe I am missing something, so please pardon any ignorance on my part. I have been stuck at the same FG for many days now. I know my yeast are able to ferment for two reasons. One, I added DME to a sample I took from the fermenter and they fermented it. Two, I added the beano to a sample and it started fermenting again so it broke down what my current yeast couldn't eat and made it edible.

Given that, how could adding new yeast help? If there are still fermentable sugars in there, what would make new yeast be able to eat what my current yeast cant, keeping in mind that I have tested that my current yeast CAN eat the sugars that beano converted and the DME?

Thanks,

David

Maybe I missed something about DME test - above you say "One, I added DME to a sample I took from the fermenter and they fermented it. "

but before you said:
"The other sample with two table spoons of DME actually went up .002 or stayed about the same."

I thought you added DME and gravity has not changed much, which could be consistent with stuck fermentation.

If what you meant is that gravity went up when you added DME, but then went back down as DME got fermented out, and still got stuck at the same value, perhaps it indicates presence of a lot of unfermentable sugars.

I would still think that adding yeast and doing forced fermentation is better test than adding DME - you are keeping sugar and alcohol content the same, and just trying to see if your original yeast, or maybe some other yeast, can finish the job.

 

[djonesax]

If what you meant is that gravity went up when you added DME, but then went back down as DME got fermented out, and still got stuck at the same value, perhaps it indicates presence of a lot of unfermentable sugars.

Yes, this. Sorry for the confusion.

 

[djonesax]

For another datapoint, I spoke to my LHBS owner and he thinks for my recipe and at 10 gallons I should be ok with 2lb of sugar but not much more. Might not lower the FG any but at least it wont be a full bodied sweet stout session beer. If the FG is not down more tomorrow, I'm going to add 2lbs of sugar and if the beer sucks, then lesson learned. I may try adding more yeast to a sample tonight as well.

David

 

[MrFancyPlants]

Try the amalyse.. it will just convert the the starches to sugar. It isn't as "ice 9 " as the beano is. It will take a couple weeks depending on the temps.

 

[djonesax]

Try the amalyse.. it will just convert the the starches to sugar. It isn't as "ice 9 " as the beano is. It will take a couple weeks depending on the temps.

My LHBS owner didnt think amalyse would help much if I had too many dextrins from a high mash temp. That was what I was thinking originally but have gotten some conflicting advice.

 

[MrFancyPlants]

It wouldn't help with dextrins, but it would help with starches, and with a gravity that high, you might have some starches to deal with. I would give it a shot..

 

[djonesax]

It wouldn't help with dextrins, but it would help with starches, and with a gravity that high, you might have some starches to deal with. I would give it a shot..

Thanks, another question ... What would have caused the starches? Poor mash conversion? I did have a .005 point lower OG than expected.

 

[MrFancyPlants]

Too short of a mash and/or temperatures above 160 or 170.. (not sure about 160), or a mash that was not stirred enough so that portions of mash were hot enough for enzyme denaturing.
It happened to me in a crockpot ESB partial mash. I used half a crushed beano for a 5g batch and a teaspoon or two of amalyse + 2-3 weeks. The gravity dropped a little too low 1.008 for me, so I added a subtle portion of lactose to rebuild the body to a 1.012 or 14 and brought the abv up to 6% with a small portion of brown sugar for priming in the keg. It was a little cidery for about a week as the brown sugar was eaten up, but it turned out great for my friend's birthday party. Be sure to label the beer as a milk... in case someone is lactose intolerant.

 

[djonesax]

I decided to go ahead and add 2lbs of boiled sugar to the fermenter. I cooled the beer back down to 63 and added the sugar which rose the temp to 67 for just a little while while before it cooled back down to 63. My calculations put the ending ABV at 5%. The air lock was bubbling in less than an hour! It will be interesting to see if the FG comes down any. If it's still at 1.028, I may split the batch and add amylase to 5 gallons and see how it does for experimentation purposes.

 

[55x11]

I decided to go ahead and add 2lbs of boiled sugar to the fermenter. I cooled the beer back down to 63 and added the sugar which rose the temp to 67 for just a little while while before it cooled back down to 63. My calculations put the ending ABV at 5%. The air lock was bubbling in less than an hour! It will be interesting to see if the FG comes down any. If it's still at 1.028, I may split the batch and add amylase to 5 gallons and see how it does for experimentation purposes.

this is great news (I guess) - please let us know how it turns out.
Everything is consistent with too many unfermentable sugars, I guess. Any idea on how high you mashed and for how long? Did you start high or keep adding boiling water to stabilize the temperature? I often find that temperature is slightly different in different parts of the mash tun, or surface/deep in the grain bed, even after rigorous mixing. It's also slightly different with different thermometers I use. Maybe 2-5 degrees, which may not sound like not much, but could be significant.

 

[djonesax]

this is great news (I guess) - please let us know how it turns out.
Everything is consistent with too many unfermentable sugars, I guess. Any idea on how high you mashed and for how long? Did you start high or keep adding boiling water to stabilize the temperature? I often find that temperature is slightly different in different parts of the mash tun, or surface/deep in the grain bed, even after rigorous mixing. It's also slightly different with different thermometers I use. Maybe 2-5 degrees, which may not sound like not much, but could be significant.

Honestly I am not positive that I mashed high but it seems most likely, I still need to check my thermometers against a digital one. I mashed in at a 156, and used direct fire low flame and re-circulation with a pump to maintain the temps when needed and mashed for 60 minutes. If I mashed high I imagine it was only by a couple degrees but wont know until I can check the thermometer which is mounted to the keggle. I ran through my process with the LHBS owner and he said it all sounded fine. The other possibility is starches like you said before. I didn't do an iodine test or anything, so maybe the mash wasn't complete or maybe I had some dough balls in there.

 

[djonesax]

I tasted the beer and took a gravity reading today. Its been 4 days since adding the sugar slurry and the gravity actually dropped a little and I am sitting at 1.024 now. The beer does taste different than before but it's not bad. It has a tiny hard to detect cidery flavor from the sugar I guess. I am going to leave it for another week and hope it works itself out.