Can an overnight mash recover a too hot mash?

[BasementArtie]

Long story short...we'll find out soon!

Last Saturday, I messed up a mash temp for my newest beer (Double NEIPA) and ending up mashing at 70-72C for 90 mins. I was trying to stir like crazy with my drill paddle (attached photo) to reduce the temp to no avail! So I thought **** it, I'll cover it and leave it over night (10hours). Came back and the temp was 62C and I carried on my brew day as planned. Pitched the yeast, lovely fluffy krausen. The OG was 1.081 and I've double dry hopped this bad boy one during fermentation and one after fermentation. I'm taking my first hydrometer sample this Wednesday, hopefully its down to 1.020ish as I wanted it to be 8% however I don't hold out much hope.

 

[AlexKay]

70 C for 90 minutes, and then only slowly down from there, might be too much for the beta. Alpha’ll be fine. You may not get the attenuation you’re looking for, but it may taste fine. Keep us posted.

 

[BasementArtie]

70 C for 90 minutes, and then only slowly down from there, might be too much for the beta. Alpha’ll be fine. You may not get the attenuation you’re looking for, but it may taste fine. Keep us posted.

Will do! I'm hoping extended time at under 68C allowed at least some beta to be converted. During my "boil" (didn't have a traditional boil) I was planning to add 0.3kg of dextrose however I upped this to 0.45kg in the hope to bring the FG down a bit. I still missed to OG by 2 points though. We'll see.

 

[doug293cz]

If alpha and beta amylase were the whole story, then an extra long mash could make up for denaturing all the beta early. However, loss of the critical enzyme for changing fermentability - limit dextrinase, cannot be recovered by additional time with alpha amylase. Limit dextrinase is the only enzyme (native to malt) that can de-branch dextrins in the wort, which is what allows more fermentable sugars to be created. Limit dextrinase denatures at slightly lower temps than does beta amylase, so a hot mash kills it off pretty quickly.

Brew on

 

[Stormcrow]

The double dry hop may induce some "hop creep" to help you out too. Fingers crossed.

 

[AlexKay]

If alpha and beta amylase were the whole story, then an extra long mash could make up for denaturing all the beta early. However, loss of the critical enzyme for changing fermentability - limit dextrinase, cannot be recovered by additional time with alpha amylase. Limit dextrinase is the only enzyme (native to malt) that can de-branch dextrins in the wort, which is what allows more fermentable sugars to be created. Limit dextrinase denatures at slightly lower temps than does beta amylase, so a hot mash kills it off pretty quickly.

Brew on

It’s a good point about limit dextrinase. But even without branching, you still need beta to make maltose. Alpha’s active site requires 5 or 6 sugars or something to bind and cleave, so it can’t make fermentable wort all by itself.

 

[mashpaddled]

To simplify what these other brewers have said--when the mash gets too hot it denatures the enzymes necessary to convert starches to sugar. You can't make new enzymes by dropping the temperature. Once the enzymes denature they are done for.

If your OG is 1.081 either there is a ton of starch in solution or you had some conversion before the mash got too hot. Remember just because the temperature reads a certain temperature at one place doesn't mean the entire mash is at that temperature at that time (especially without recirculation). You could add enzymes now (the same ones you get in the mash are available primarily for distillers) but I'm not sure if that would affect any of the hop compounds and might make your beer too thin. I'd probably just leave it alone and if it tastes ok enjoy it for what it is.

 

[AlexKay]

Once the enzymes denature they are done for.

For a mental image: you can’t un-fry an egg by leaving it on the counter to get cold.

 

[doug293cz]

It’s a good point about limit dextrinase. But even without branching, you still need beta to make maltose. Alpha’s active site requires 5 or 6 sugars or something to bind and cleave, so it can’t make fermentable wort all by itself.

I haven't read that about alpha. Do you have a reference?

Edit: I found the following statement in the Worthington Enzyme Manual:

"alpha-Amylase catalyzes the hydrolysis of internal alpha-1,4-glucan links in polysaccharides containing 3 or more alpha-1,4-linked D-glucose units, yielding a mixture of maltose and glucose."​

​

This means alpha can act on anything with 3 or more glucose units (maltotriose and larger), but cannot create 2 glucose from a maltose, and can reduce starch to limit dextrins and fermentable sugars without the assistance of beta-amylase.

Brew on

 

[BasementArtie]

To simplify what these other brewers have said--when the mash gets too hot it denatures the enzymes necessary to convert starches to sugar. You can't make new enzymes by dropping the temperature. Once the enzymes denature they are done for.

If your OG is 1.081 either there is a ton of starch in solution or you had some conversion before the mash got too hot. Remember just because the temperature reads a certain temperature at one place doesn't mean the entire mash is at that temperature at that time (especially without recirculation). You could add enzymes now (the same ones you get in the mash are available primarily for distillers) but I'm not sure if that would affect any of the hop compounds and might make your beer too thin. I'd probably just leave it alone and if it tastes ok enjoy it for what it is.

It must be loads of starch in the wort then as I measured constantly at different depths, different areas, in the grain bed, under the grain bed, to the side of the grain bed with two different thermometers and probes and all readings were above 70C, even after drill mixing everything constantly.

I am surprised to see how active fermentation was though. We'll see how fermentable it really was soon, in a moment of truth.

Hopefully the extra dextrose and a bit of hop creep has helped bring it down or some "unknown" (I know very unscientific, optimistic and unlikely) reaction after destroying the enzymes and ability conversion the overnight mash has done something miraculous that no-one expected .

Anyone care to guess what the FG will be haha?

 

[AlexKay]

I haven't read that about alpha. Do you have a reference?

Nope, I checked my books, and I don't. It was something one of my professors said, so I'm inclined to trust it, but there's of course the possibility I'm mis-remembering.

 

[Beermeister32]

I had a similar situation once. I ended up fixing it by doubling down - I doubled the recipe on the fly adding more grain. The new grain added had enough enzymes to complete the mash.

So, I ended up with 10 gallons rather than 5. Not the worse thing to happen! Turned out pretty good too!

 

[BasementArtie]

I had a similar situation once. I ended up fixing it by doubling down - I doubled the recipe on the fly adding more grain. The new grain added had enough enzymes to complete the mash.

So, I ended up with 10 gallons rather than 5. Not the worse thing to happen! Turned out pretty good too!

Unfortunately I didn't have the appropriate sized container to do something like that. I was already pushing my limits with a 7kg grain brew.

 

[superiorsat]

Looks like you mashed between 158-161.6 farenheit. It should make a very heavy beer. Doubt you will hit your 8% mark but you can always add honey or sugar to raise abv and thin it out some. A little cold water would have went a long way to cool it down in a hurry. You could have just subtracted it from your sparge water.

 

[Miraculix]

Looks like you mashed between 158-161.6 farenheit. It should make a very heavy beer. Doubt you will hit your 8% mark but you can always add honey or sugar to raise abv and thin it out some. A little cold water would have went a long way to cool it down in a hurry. You could have just subtracted it from your sparge water.

You don't thin it out by adding more sugar, you just raise the abv. Replacing grain derived sugars with simple sugars thins a beer out but this is not possible anymore.

 

[BasementArtie]

add honey or sugar to raise abv and thin it out some

Yeah that was my first port of call I increased the amount of dextrose I put in my non traditional boil phase.

A little cold water would have went a long way to cool it down in a hurry. You could have just subtracted it from your sparge water.

Unfortunately I was already at the maximum in my kettle so I couldn't add anything to cool it down. Also I do full volume biabasket so no sparge either. Which left me a bit helpless.

 

[superiorsat]

Yeah that didn't leave much wiggle room. I think I would have sacrificed a little starch water and replaced with cold water as you can always add more sugar later. I've had to dump a little before when my grain bill was over 50 pounds on an imperial stout and beersmith missed my strike water calculation by about a half gallon to fit all the grain.

 

[superiorsat]

Either way see how it finishes and again you can add more sugar/honey to thin and bring up abv if it ends up weaker and thicker than you wanted.

 

[hottpeper13]

10 hr mash,I'll say finishes at 1.021. I do a lot of overnite mashing and it always finishes low. I read somewhere that beta denatures after 30 min at 154*. I mash in at 154* and mash for 6-7 hrs(short sleeper). my last one was a Kolsch that hit 1.060 (calculated for 1.050) and finished at 1.004. I couldn't taste the honey malt so if I do that again i'll up the quantity.

what do I win if I'm right?

 

[superiorsat]

You don't thin it out by adding more sugar, you just raise the abv.

Raising ABV adds alcohol which lowers FG, therefore thins it out some. If I have a beer that is too sweet I'll add honey making ABV higher but it always brings the final gravity down as long as the new sugar ferments. Alcohol is less dense than water.

 

[Miraculix]

I also think it's going to be around 1.02. I say 1.18.

Starting to degrade and completely gone are two different things. Even after an hour at 72, there's going to be a little bit beta left. Giving extended time, this should still do something to the wort.

 

[Miraculix]

Raising ABV adds alcohol which lowers FG, therefore thins it out some. If I have a beer that is too sweet I'll add honey making ABV higher but it always brings the final gravity down as long as the new sugar ferments. Alcohol is less dense than water.

Thinning something out in terms of beer is more related to sweetness than to gravity of the liquid. As you won't remove any of the residual sugars by adding highly fermentable sugars, you are not doing anything to the sweetness. That's why you can't unsweeten a beer with adding sugar after fermentation.

You "unsweeten" it by replacing a portion of the grain bill with simple sugars, not by adding the sugar on top of it.

 

[rallenhall]

I wouldn't alter it; you have a nice experiment going on with a single variable. Finish it out and see what you think. Although the rigor of Brulosophy experiments is often questioned, there's some interesting perspectives here: https://brulosophy.com/2015/10/12/the-mash-high-vs-low-temperature-exbeeriment-results/

 

[BasementArtie]

10 hr mash,I'll say finishes at 1.021. I do a lot of overnite mashing and it always finishes low. I read somewhere that beta denatures after 30 min at 154*. I mash in at 154* and mash for 6-7 hrs(short sleeper). my last one was a Kolsch that hit 1.060 (calculated for 1.050) and finished at 1.004. I couldn't taste the honey malt so if I do that again i'll up the quantity.

what do I win if I'm right?

You get to perform a thesis on what mechanisms and enzymatic processes within the overnight mash after a 90 min mash of over 70C allowed the beer to finish so low, considering there should be loads of non-fermentable residual sugars floating around. Enjoy your winnings if you're the lucky enough to be crowned.

 

[IslandLizard]

I was trying to stir like crazy with my drill paddle (attached photo) to reduce the temp to no avail!

Adding cold water and/or ice cubes will bring the temp down quickly. That's how you do it.
Just stirring, not so much, perhaps only a couple degrees.

 

[BasementArtie]

Adding cold water and/or ice cubes will bring the temp down quickly. That's how you do it.
Just stirring, not so much, perhaps only a couple degrees.

As I've said previously this wasn't an option unfortunately as I was already at the brim of my capacity. Lessons learned for next time pay more attention to strike temp

 

[Miraculix]

As I've said previously this wasn't an option unfortunately as I was already at the brim of my capacity. Lessons learned for next time pay more attention to strike temp

I've been there multiple times as well

Last one was an American red, that really finished much too sweet....

 

[IslandLizard]

As I've said previously this wasn't an option unfortunately as I was already at the brim of my capacity.

Scoop some wort out to make space, then add back later when it has cooled, to finish.

Adding ice or ice cold water works the quickest. 1 liter would likely have been sufficient to drop 6 degrees C.

 

[BasementArtie]

Scoop some wort out to make space, then add back later when it has cooled, to finish.

Adding ice or ice cold water works the quickest. 1 liter would likely have been sufficient to drop 6 degrees C.

Would water chemistry be effected? Would I have to have some treated (campden) water frozen. Or would normal Ice have been okay?

 

[superiorsat]

. As you won't remove any of the residual sugars by adding highly fermentable sugars, you are not doing anything to the sweetness. That's why you can't unsweeten a beer with adding sugar after fermentation.

You are right you won't remove any unfermentable/residual sugars, you will just be diluting them. No one said adding after fermentation , I said" as long as the new sugar ferments ". If you are adding water or alcohol to a final volume of beer you most certainly are thinning it out as the total volume of beer increases either with water or alcohol the sugar stays the same and the sugar level does not increase as the volume increases in a larger volume of beer. Lets say my beer is too sweet at 1.026 and I add water to dilute or sugar to ferment and get extra alcohol and I end up at 1.024 that is about my threshold for beer I can still enjoy with out it being to sweet. I would disagree and say with adding volume in one way or another you can un-sweeten beer to a certain point. If i put a cup of sugar in a gallon of water and a cup of sugar in 5 gallons of water the 5 gallons is less sweet.

 

[chazam]

What's alpha and beta?

 

[IslandLizard]

Would water chemistry be effected?

Very minimally.
If you had added 1 liter of cold water or ice (or replaced it), water chemistry would have been affected by about 1/25 if you had 25 liters of mash water in your kettle.

Would I have to have some treated (campden) water frozen. Or would normal Ice have been okay?

If your water is (heavily) chlorinated, yeah, adding a pinch of "Meta" powder to the "correction water" would be best. But first of all, you need to work fast, bringing the temps down. The mash left for 10 minutes in that high range can make a noticeable difference.

Best is to nail the target temp after it's stirred and fully hydrated.
It may take a few times to hone in on your strike water temp to come out right on target. There are calculators for that, but each system is a little different, so you still need to tweak it a little. Keep notes.

Keep in mind, it's much easier to add (ice) cold water to drop the mash a few degrees than it is to raise it by the same amount. So next time, yeah, have some ice cold, Campden-treated water ready to go.

When higher temp mashing (to reduce fermentability, say in Milds), it's best to have the mash temp come down from the top slightly, while stirring, than it is to raise it. Reason is, enzymatic conversion is relatively fast, in the first 10 minutes half can be done already. It depends on how finely milled the grist is, and how fast you can fully hydrate it. The thinner the mash, the faster hydration and thus conversion.
FYI, full volume (BIAB) mashes are thin.

You may enjoy a bit higher mash efficiency by including a sparge. Even a small, (e.g., 2 gallon) dunk sparge is better than none, as high gravity wort remains trapped in the grist. Squeezing or pressing can only recover so much.

 

[bracconiere]

Anyone care to guess what the FG will be haha?

when i did my rice beers with alpha amylase, before i knew i needed to tag team it with gluco too, i usually got a FG of around 1.035.

but those had an OG of 1.060

 

[BasementArtie]

I am shook, shocked, flabbergasted, flummoxed, bamboozled. Plain old stumped.

The Wednesday morning hydrometer reading has just given me a FG of 1.013 (my hydro reads to 1.000 with distilled water to TOP of the meniscus @20C). Just checked the hydro and it's still calibrated, not cracked or broken. That's a ~83% attenuation.

Also before anyone asks I can guarantee the temperature of the mash didn't drop below 70C for 90minutes...beer/wort just seem to be more resilient to my f*ck ups than I thought.

As I said at the start this stumped me. I was expecting anything in the range of 1.020-1.030FG however I don't know what's happened.

Did the overnight mash work...are there even mechanisms for it to work?

Does BIAB mash thickness come into play, from BYO "Thicker mashes tend to retain more beta-amylase activity at high mash temperatures than do thin mashes. This is because beta-amylase is more stable when joined with its substrate than when it is not."?

Does water chemistry have anything to with it?

Let me know what you guys and gals think.

 

[hottpeper13]

Yes, yes and yes.

 

[doug293cz]

...

Does BIAB mash thickness come into play, from BYO "Thicker mashes tend to retain more beta-amylase activity at high mash temperatures than do thin mashes. This is because beta-amylase is more stable when joined with its substrate than when it is not."?

...

Except that BIAB (usually) employs a much thinner mash than a typical three vessel system.

You might be seeing "Hop Creep":

"There is evidence that hops have amylolytic enzymes in or on them that biochemically modify beer during dry-hopping, leading to degradation of long-chain, unfermentable dextrins into fermentable sugars. This increase in fermentable sugars can, in the presence of yeast, give rise to a slow secondary fermentation, which is referred to as 'hop creep.'"​

Brew on

 

[BasementArtie]

Except that BIAB (usually) employs a much thinner mash than a typical three vessel system.

You might be seeing "Hop Creep":

"There is evidence that hops have amylolytic enzymes in or on them that biochemically modify beer during dry-hopping, leading to degradation of long-chain, unfermentable dextrins into fermentable sugars. This increase in fermentable sugars can, in the presence of yeast, give rise to a slow secondary fermentation, which is referred to as 'hop creep.'"​

Brew on

So I agree mash thickness is thin compared with a three vessel system with BIAB so it's unlikely this. My thickness so this brew was 3.3L/kg which overall isn't anything too large.

How fast does hop creep act / drop FG and provide consumable/fermentatable sugars? If it's a slow process I doubt it would be this either (in isolation) as the brew has only been in contact with hop matter (~200g) for roughly 7days.
Seems a bit of a stretch that alone brought the FG down roughly 10points on the best case scenario I was expecting, or maybe I'm underestimating how huge hop creep can be and really need to factor this in next brew I make .

 

[RM-MN]

I messed up a mash temp for my newest beer (Double NEIPA) and ending up mashing at 70-72C for 90 mins.

OK, so you had the grains in the mash for 90 minutes. How much of that time was the actual conversion of starch to sugar? It takes several minutes to denature enzymes, most often mentioned is 10 minutes at 170F (about 77C) for mash out. How finely did you have your grains milled? Very finely milled grains can get you full conversion in less than 10 minutes that it might take to denature the enzymes and the rest of your 90 minutes were used to extract flavor and sugars. I often will do my BIAB mash at 156 to 158F (69 to 71C) and get a final gravity of 1.012 because my conversion is over before the enzymes are denatured.

 

[BasementArtie]

OK, so you had the grains in the mash for 90 minutes. How much of that time was the actual conversion of starch to sugar? It takes several minutes to denature enzymes, most often mentioned is 10 minutes at 170F (about 77C) for mash out. How finely did you have your grains milled? Very finely milled grains can get you full conversion in less than 10 minutes that it might take to denature the enzymes and the rest of your 90 minutes were used to extract flavor and sugars. I often will do my BIAB mash at 156 to 158F (69 to 71C) and get a final gravity of 1.012 because my conversion is over before the enzymes are denatured.

So I overcooked my strike temp and after dropping the grain in and thoroughly mixed my mash it was at 72C which probably was taken 5 mins after dough-in. Then it was a frantic 85mins that followed with the lid off stirring/mixing and constantly measuring temp in various places withing the mash where I only got it down to 70C at 90mins. This is when I called it a day. Covered it back up and left it for 10 hours. Came back was at 62C.


So my last brew was a 9% quad which I brewed at 65-63C and nailed the temperature and that only dropped to 1.009 FG (although if it was a Tripel with all lighter grain I'm thinking it would have been lower). So for messing up temp on this brew and still getting an FG of 1.013 I'm very happy although I don't understand how.

 

[Homebrew Harry]

I've been lurking on this one. I'm glad it turned out OK