Mash temp too hot

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CDS

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Well, on my last brew day of the year, I managed to screw-up. Just sure not how much. I'm brewing a Roggenbier (BIAB). Recipe called for a 152F 60-minute mash. The temp was starting to fall a bit around the 40-min mark, and so I turned on the cooktop and immediately got distracted - temp soared to 170F before I got back to it. I stirred like crazy - added a small bit of cool water, but didn't really help. so looks like the last 20 minutes of my mash is going to hang in the high 160s.
Any thoughts on what I should expect as my final results? Anything I could do in the future to cool it back down - or is there even a point in trying to cool it down, since the higher temps would have damaged the enzymes?
 

hotbeer

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Any thoughts on what I should expect as my final results?
Beer. Maybe not quite the beer the recipe was trying to get you.
Anything I could do in the future to cool it back down
I don't know for certain, others with more knowledge about what's really going on on the more scientific level of mashing will have to say. Maybe add some of the sparge water you have heating up if it's not already over your mash temps, or just add some cooler water and subtract that amount from your sparge water. Don't know if that will mess up any enzymatic or other starch/sugar stuff going on and make a bad situation worse.

For your excursion to 170°F at the 40 minute mark, probably not worth worrying about
 

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I don't usually run my mash over 30 minutes but I have experimented so that I know how long it takes for full conversion with my milling. If your grain was milled anywhere near fine, conversion was well over before you started adding heat. Add to that, the mash does not instantly come to 170 degrees so you had a ramp up time.
 
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CDS

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BIAB is at its best when it's easy. For the future, wrap the kettle with a few towels, blanket, sleeping bag, winter coat, Reflectix, whatever. If it drops a few degrees over the hour, so be it. Not a problem whatsoever.
You're right of course. I do tend to get carried away and obsess about stuff like temp. I should have just left it alone to begin with. Every brewday is a learning experience.
 

PCABrewing

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Well, on my last brew day of the year, I managed to screw-up. Just sure not how much. I'm brewing a Roggenbier (BIAB). Recipe called for a 152F 60-minute mash. The temp was starting to fall a bit around the 40-min mark, and so I turned on the cooktop and immediately got distracted - temp soared to 170F before I got back to it. I stirred like crazy - added a small bit of cool water, but didn't really help. so looks like the last 20 minutes of my mash is going to hang in the high 160s.
Any thoughts on what I should expect as my final results? Anything I could do in the future to cool it back down - or is there even a point in trying to cool it down, since the higher temps would have damaged the enzymes?
So you really just mashed-out sooner than planned.
As jdauria said most conversion was already done.
JOOC, what recipe are you using for the roggenbier, I'm getting ready to try one.
 
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CDS

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So you really just mashed-out sooner than planned.
As jdauria said most conversion was already done.
JOOC, what recipe are you using for the roggenbier, I'm getting ready to try one.
Here's the original recipe I'm using (which I've since converted to BIAB using brewfather):
 
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CDS

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Just wanted to follow-up with the results of this brew, in case any one in the future has the same problem and is wondering what happened! This was a weird one, and quite unlike my first attempt at Roggenbier. Firstly, the wort was extremely viscous. Even though I added rice hulls to this batch it took forever to drain (BIAB remember), and when taking gravity readings the hydrometer would get pulled to the side of the flask - it was really hard to get a good spin on it! OG came in 5 points higher than expected, at 1.060.

Fermentation started very strong, even at lager temp, it was super active within hours. I had built a starter from a newish pack of Wyeast 2206 and aerated well as usual. Fermented at 52F. Within a couple days observable activity had stopped. Gravity reading showed 1.025 or ~75% of expected FG of 1.013.

A week later the gravity reading had only moved 1 point, and I concluded fermentation had ceased after several subsequent readings held at 1.023. So I ended up 10 points higher than anticipated (FG 1.023, expected 1.013), despite healthy yeast, and good temperature control.

I think accidentally letting the mash get too hot is the culprit here. Even though most say most conversion happens in the first 30 minutes, I wonder if rye malt takes longer, and I ended up with a high amount of dextrins. Mouthfeel is definitely way more viscous than my previous batch of Roggenbier. It's still a drinkable beer - I'll just chalk it up to another brewing lesson learned.
IMG_4412.jpg
 

PCABrewing

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Just wanted to follow-up with the results of this brew, in case any one in the future has the same problem and is wondering what happened! This was a weird one, and quite unlike my first attempt at Roggenbier. Firstly, the wort was extremely viscous. Even though I added rice hulls to this batch it took forever to drain (BIAB remember), and when taking gravity readings the hydrometer would get pulled to the side of the flask - it was really hard to get a good spin on it! OG came in 5 points higher than expected, at 1.060.

Fermentation started very strong, even at lager temp, it was super active within hours. I had built a starter from a newish pack of Wyeast 2206 and aerated well as usual. Fermented at 52F. Within a couple days observable activity had stopped. Gravity reading showed 1.025 or ~75% of expected FG of 1.013.

A week later the gravity reading had only moved 1 point, and I concluded fermentation had ceased after several subsequent readings held at 1.023. So I ended up 10 points higher than anticipated (FG 1.023, expected 1.013), despite healthy yeast, and good temperature control.

I think accidentally letting the mash get too hot is the culprit here. Even though most say most conversion happens in the first 30 minutes, I wonder if rye malt takes longer, and I ended up with a high amount of dextrins. Mouthfeel is definitely way more viscous than my previous batch of Roggenbier. It's still a drinkable beer - I'll just chalk it up to another brewing lesson learned.
View attachment 757267

Nice write-up.
Do you think maybe Rye Malt has an effective lower level of modification?
How do you find that little detail. Or maybe someone else knows if that is normal.
I am planning t attempt a Roggenbeir so it would be nice to know.

Edit: Just went to the Breiss site and they say their Rye malt is fully modified and should perform well in Single infusion mash when used at <20%. They also say at levels approaching 20-50% it is beneficial to use Betaglucanasa enzyme to aid managability.
That's how I read it anyhow.
 
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CDS

CDS

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Nice write-up.
Do you think maybe Rye Malt has an effective lower level of modification?
How do you find that little detail. Or maybe someone else knows if that is normal.
I am planning t attempt a Roggenbeir so it would be nice to know.
I'm not sure about the lower level of modification question - that was my first thought, but dammit, I just thought of another potential variable! This time I ran the rye malt through my mill twice for a finer crush. Apparently rye malt has high beta glucan content, which increases viscosity - now I wonder if crushing it finer was what lead to that thicker wort.
 
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CDS

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How are you measuring your final gravity?
Does the beer taste good, or overly sweet?
I'm using a hydrometer to measure FG.
The beer is drinkable, it's definitely sweeter than my previous batch, but not cloyingly so.
 

DBhomebrew

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I'm using a hydrometer to measure FG.
The beer is drinkable, it's definitely sweeter than my previous batch, but not cloyingly so.

Depending on your intended carb level, CO2 (carbolic acid) can help take the edge off 'sweet, but not cloyingly so'.
 

VikeMan

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I think accidentally letting the mash get too hot is the culprit here. Even though most say most conversion happens in the first 30 minutes, I wonder if rye malt takes longer, and I ended up with a high amount of dextrins.

Yes, letting the mash get too hot, too soon, was certainly a factor in the fermentability of the wort. Here's the thing... any statement that "full conversion happens in X minutes" may be true (depending on the brewhouse and the recipe), but is also unintentionally misleading. That's because "full conversion" just means conversion of starches into things that aren't starches, i.e. a mixture of fully fermentable sugars, partially fermentable sugars, and unfermentable dextrins. The longer the mash goes (to a point), the more fermentable the wort's carbohydrate profile.

You can look up experiments by Kai Troester and by Greg Doss that will give you some quantitative idea about this.

ETA: The main fermentabilty factors...
- Yeast Strain
- Grain Bill
- Mash Temp
- Mash Length
 
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