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Big RIS - may have mashed too hot

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FatDragon

Not actually a dragon.
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I brewed a big RIS a few days ago, and long story short, I may have reached temperatures of 74C (165F) or higher during the mash, when my target was 69C (156F) for a full-bodied RIS.

I finished the brew (OG 22 Plato), chilled, and pitched like normal. I've got some fermentation activity, but it's not very vigorous. Is it time to start worrying?

What are my options if I end up getting stuck at some crazy-high FG? If I could find lab-grade amylase enzyme, could I pitch some of that into the fermenter to convert some sugars and dry it out a bit? What about blending? How would I go about designing a recipe to blend and balance this beer?

Original recipe as follows:

Volume into fermenter: ~6 gallons (trub and all)
OG: 22 plato (1.093)

6.10 kg Pale Malt (2 Row) China (2.5 SRM) Grain 1 58.9 %
1.00 kg Munich Malt - 20L (20.0 SRM) Grain 2 9.7 %
1.00 kg Vienna Malt (3.5 SRM) Grain 3 9.7 %
0.50 kg Carafa II (412.0 SRM) Grain 4 4.8 %
0.50 kg Roasted Barley (300.0 SRM) Grain 5 4.8 %
0.34 kg Carared (20.0 SRM) Grain 6 3.3 %
0.25 kg Special B Malt (180.0 SRM) Grain 7 2.4 %
0.16 kg Caramel/Crystal Malt - 60L (60.0 SRM) Grain 8 1.5 %
50.00 g Calypso [13.00 %] - Boil 90.0 min Hop 9 67.2 IBUs
25.00 g Calypso [13.00 %] - Boil 20.0 min Hop 10 19.0 IBUs
2.0 pkg Nottingham (Danstar #-) [23.66 ml] Yeast 11 -
0.50 kg Homemade Candi Sugar - 290 degrees (160.0 SRM) Sugar 12 4.8 %
 
More details please. How long was it 165F? Those enzymes don't denature immediately, if you stirred it down to 156F and left it for a while it probably converted just fine, given that you nailed your gravity. Notty is pretty damn attenuative, too, so I wouldn't worry just yet.
 
I left the lid open and stirred very gently, but the mash was within about a centimeter of the lip, so vigorous stirring or adding cold water were out of the question. Combine that with the poor performance of the thermometer (variance over 10C when I put on or removed the lid) it could have been five minutes or fifteen or maybe it didn't get that hot at all. I know that's maddeningly unspecific, but I'm not sure what else I can say. I know it's time to relax and all that, but I'd like to have a plan of attack in place just in case it gets stuck.
 
I'm inclined to say no plan. You need beta amylase if you wanted to change things, really, though some sugar can dry it out - but your gravity is so high that I wouldn't want to do that to the yeast. Adding beta amylase can be a bit of an adventure, too. You're more likely to screw it up by messing with it; there's a much better chance that it turns out fine on its own, especially given that you don't even know whether your thermometer was right.
 
You can always whip up a gallon of dry RIS and blend it back to get the body/flavor you want. If it happens again, try chilling the mash with an immersion chiller if you can fit it in the tun without overflow.
 
You can always whip up a gallon of dry RIS and blend it back to get the body/flavor you want. If it happens again, try chilling the mash with an immersion chiller if you can fit it in the tun without overflow.

That's not a bad idea.

What do you think of something like pitching brett to eat those "unfermentable" sugars?
 
I'm inclined to say no plan. You need beta amylase if you wanted to change things, really, though some sugar can dry it out - but your gravity is so high that I wouldn't want to do that to the yeast. Adding beta amylase can be a bit of an adventure, too. You're more likely to screw it up by messing with it; there's a much better chance that it turns out fine on its own, especially given that you don't even know whether your thermometer was right.

I won't make any moves until I'm certain I'm stuck at an untenably high FG, but I would like to have a backup plan in case that happens.

You can always whip up a gallon of dry RIS and blend it back to get the body/flavor you want. If it happens again, try chilling the mash with an immersion chiller if you can fit it in the tun without overflow.

The kettle (I do BIAB) was full to within a centimeter of the lip, unfortunately, but I'll put that into my playbook in case I run into the same issue with a bit more headspace.

That's not a bad idea.

What do you think of something like pitching brett to eat those "unfermentable" sugars?

I've never used Brett and only have limited access to suppliers who might carry it, but this sounds like an intriguing idea. Would this actually work, or would the Brett get stuck on the same sugars that the Sacc can't eat?
 
Hard to say as I've never tried to do that with brett, and it's a slow eater, but with time it seems to eat everything, even dead Sacc.
 
The kettle (I do BIAB) was full to within a centimeter of the lip, unfortunately, but I'll put that into my playbook in case I run into the same issue...


You can always draw off a gallon of the wort to a separate vessel temporarily, too (and then recombine later).
 
You can always draw off a gallon of the wort to a separate vessel temporarily, too (and then recombine later).

Would have been a good idea. That'll go into the playbook as well.

It was kind've a weird brewday because I was pushing the limits of my kettle and my cheap BIAB bags. I thought about double-bagging with both of my BIAB bags to ensure that they didn't break under the weight of the wet grain (a likely scenario), but then I got the idea to put my first bag on the kettle, toss half the grain in, then put the second bag above that and put the rest of the grain in that one, so instead of one bag holding 10kg of grain plus absorbed water, it was two bags with 5 kg.

It worked great for draining, bucket sparging, and squeezing, but it made stirring difficult and relatively ineffective, which, combined with the thick mash and low ambient temperature, was one of the major contributors to the wild fluctuations of my temperature readings - I think at some points the mash was literally several degrees cooler or hotter at different spots in the kettle. The result was that with the lid open, my thermometer (with a wired probe, so I can move it around but I can also measure with the lid on) read ~60 C near the surface, while putting the lid on resulted in the thermometer's reading climbing above 74 C over the course of about a minute.

I shot off an email to the one guy I know of who might have Brett in stock and for sale here in China, both to see if he has any, and to see if he thinks it would help in the event of a stuck fermentation. I guess it's wait-and-see time now...
 
I would suggest WAITING. If you get stuck at a high FG, then try to dry it out. I'd be inclined to try either method mentioned, amylase or brewing a low mash temp DRY batch and combining, amylase being my preferred method.
 
Would have been a good idea. That'll go into the playbook as well.

It was kind've a weird brewday because I was pushing the limits of my kettle and my cheap BIAB bags. I thought about double-bagging with both of my BIAB bags to ensure that they didn't break under the weight of the wet grain (a likely scenario), but then I got the idea to put my first bag on the kettle, toss half the grain in, then put the second bag above that and put the rest of the grain in that one, so instead of one bag holding 10kg of grain plus absorbed water, it was two bags with 5 kg.

It worked great for draining, bucket sparging, and squeezing, but it made stirring difficult and relatively ineffective, which, combined with the thick mash and low ambient temperature, was one of the major contributors to the wild fluctuations of my temperature readings - I think at some points the mash was literally several degrees cooler or hotter at different spots in the kettle. The result was that with the lid open, my thermometer (with a wired probe, so I can move it around but I can also measure with the lid on) read ~60 C near the surface, while putting the lid on resulted in the thermometer's reading climbing above 74 C over the course of about a minute.

I shot off an email to the one guy I know of who might have Brett in stock and for sale here in China, both to see if he has any, and to see if he thinks it would help in the event of a stuck fermentation. I guess it's wait-and-see time now...

Based on what you've said, I suspect it ferments okay as-is. All hunches wrong or your money back.
 
First SG check after 12 days in the fermenter - 7 plato/1.028. Not as low as I was hoping, but there's still time.

Looks like the high mash is probably holding it back a little bit, but most of the issue is my poor work leading up to the brew; I use Plato for gravity measurements because that's what's available on Chinese hydrometers, but it's not as intuitive as the SG scale to me, so I see '22 plato' OG and think I'm working on a potential 13% beer, so I plan to mash at 156 to keep it in the 11% range; when really I'm working on a potential 10-11% beer, so a lower mash would have suited my intentions better.

Maybe I'll invert or lightly maillardize a pound of sugar and toss it in to dry it out and bolster it a bit for aging.
 
Only had 300 grams of table sugar in the house after making some caramel coffee syrup the night before, so I made some very light caramel syrup and tossed it in the fermenter when it had mostly cooled. Hoping to end up around 5.5 plato if possible and toss it in the carboy for some long-term aging.
 
Further update for anyone who's reading (and note-to-self if nobody is):

Got home from work yesterday and opened the beer room door. The airlock showed no signs of activity, but the room was filled with a strong and delicious aroma of fermenting beer, so the syrup addition definitely got things moving again. It'll sit another week or so, at which point it'll get another gravity reading and head into the carboy for a couple months of bulk aging.

I have no CO2 equipment, would it be wise to give it a tablespoon or so of sugar when I go to secondary to clear the headspace? Alternatively, I'm pretty sure I have enough in the bucket to fill the carboy up to the stopper; how full is too full in the secondary?

You've seen the recipe (plus 300 grams of sugar very lightly caramelized and added after a week and a half of primary), does anyone have opinions on secondary adjuncts at this point? Oak (in secondary, how long?)? Coffee? Cocoa nibs?
 
I have no CO2 equipment, would it be wise to give it a tablespoon or so of sugar when I go to secondary to clear the headspace?

Alright I did a big beer that lagered in secondary for a long time and I'll give you my advice after having that disaster.

First, I had too much beer for that little carboy. I REALLY regret throwing out a whole gallon of that stuff. Don't waste the beer if you can help it.

Second, it didn't need secondary. I know there's a layer of trub, but you can still add the stuff you want in the primary bucket. It'll be fine. You're only aging a couple months, if you want to avoid oxidation then don't move it.

I've never tried the sugar thing but you probably don't want active fermentation while you've got oak, coffee, and cocoa in it as sometimes extra stuff interacts strangely with fermentation. I've also not tried oak but from what I've read, you probably need to read up on it if you want to do it. Cubes > chips, needs a certain amount of time, etc.
 
Alright I did a big beer that lagered in secondary for a long time and I'll give you my advice after having that disaster.

First, I had too much beer for that little carboy. I REALLY regret throwing out a whole gallon of that stuff. Don't waste the beer if you can help it.

Second, it didn't need secondary. I know there's a layer of trub, but you can still add the stuff you want in the primary bucket. It'll be fine. You're only aging a couple months, if you want to avoid oxidation then don't move it.

I've never tried the sugar thing but you probably don't want active fermentation while you've got oak, coffee, and cocoa in it as sometimes extra stuff interacts strangely with fermentation. I've also not tried oak but from what I've read, you probably need to read up on it if you want to do it. Cubes > chips, needs a certain amount of time, etc.

I haven't decided just how I'm going to deal with the excess, which should probably be around half a gallon, but it won't be dumped. Probably a small bucket fermenter, but if there's significantly less I might just use a couple brown plastic kvass bottles and a little bit of simple syrup. I'm definitely leaning towards a tablespoon of sugar in the carboy for secondary (and likewise if I secondary any leftovers in another vessel). If nothing else, it's a little extra insurance against oxidation, and that little bit of fermentation shouldn't affect any adjuncts I might use.

For oak, cubes (or spirals) are unfortunately not an option - availability is pretty much limited to French oak chips. I'm leaning towards using them, so I'll do some research to try and avoid overdoing it; is it just a question of total surface area? Might need a new thread or just some searching in other threads, but if anyone reads this I wonder if I should be using a light oak or something darker for this brew. I'd also be interested in hearing if I would get worthwhile contributions from one of my 10-15 year single malts or Johnny Walker Double Black or if I should just cheap out with a couple ounces of some Jameson passed on to me by a fellow expat when he left China.

I'm leaning against coffee and cocoa. A dozen or so changes from the original recipe are probably enough...
 
For oak, cubes (or spirals) are unfortunately not an option - availability is pretty much limited to French oak chips. I'm leaning towards using them, so I'll do some research to try and avoid overdoing it; is it just a question of total surface area?

Definitely do some searching, fresh oak is a bit astringent from what I've read but I'm not an authority so don't take my word on this - I believe one solution is to make a tincture with it and toss the liquid, which should take that astringency with it.
 
I am interested in how this turns out, as I am looking at the same situation. I brewed a scottish ale and planned on mashing at 158f. Usually, since I do 12-14 gallon batches, what ever temp I start the mash at, I end with. I have always worried about my electronic thermometers being off. Well, when I opened the lid after an hour and checked my temp with a glass thermo, I was at 165f! I added some cool water and dropped it down to 150f, for 20 minutes more. I ended up with a OG of 1.078 . I am going to check tomorrow to see where I am at on my gravity, I am expecting it to be still high.

Since this is not acceptable to me, I ordered Thermoworks, Therma K Professional Thermocouple Meter with a waterproof thermocouple. This will allow me to watch my mash temp so I can keep my temp under control with much greater accuracy and precision.
 

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