Allowable Mash Temp Drop

emdi

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New member and poster. Thanks to anyone and everyone that can help.

How much can the mash temperature drop from start to finish before it causes problems. I realize you can wrap the mash tun to help conserve heat but after an hour the temp will have fallen, especially when only doing a 5 gal batch. So how much can the temp drop or should I add hotter water to keep the temp up or maybe turn the burner back on? I haven't been able to find anything about this anywhere.

Thanks.
 
I'm not honestly sure myself. I generally lose no more than 2-3C during an hour with my cooler.
 
If I’m mashing at 152°, I’ll plan on starting the mash at 153. When it falls to 151, I’ll put the heat on for a bit. It’s easy to overshoot it. Nothing says you can’t turn the heat back on. Make sure you stir.
 
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The big thing is conversion. You can get conversion during a pretty wide range of temps. Some of the best beers I've brewed were under my target temp for mash. Until I got new equipment, I just started a few degrees high and let the temp drop through my desired range. I jacked up my grain weight once and mashed at 145 with no issues. Some styles are more sensitive to it though. Lower is dryer. Higher is sweeter.
 
If you're working in a cooler, temperature drop is inevitable. Also, the outsides of your mash will be cooler than the middle. So, in general, don't worry about it too much unless you're using some kind of active heating system. Most conversion happens early on and the warmer temperatures denature beta amylase so my general advice, don't worry about it too much.
 
Since it's pretty impossible to micromanage the temp of the entire mass of water and malt that's doing the work of making sugars for you, the best thing you can do is be consistent in your process, temp monitoring, timing, etc and judge from the resulting wort how best to run your mash. If you mash in at a certain temp, stir a certain amount, rest for a certain time and come out with the desired fermentability and residual sweetness and body then duplicate that process as closely as possible. If you need more attenuation, start lower and if you're lacking body, etc, start a little higher.
 
Many thanks for the reply's. I was really hoping you would say that. I did start a degree or two higher and then it cooled to about 3 or 4 degrees cooler when done. I use my mash tun for BIAB so it's used for boiling as well. I've set up a hoist with a strainer above the mash tun so when I remove the bag I place it in the strainer so I can sparge and heat the wort at the same time. The hoist basically acts as another person so I can do it myself. My first batch is currently fermenting so I have yet to see how it turned out. Fingers crossed.
 
Many thanks for the reply's. I was really hoping you would say that. I did start a degree or two higher and then it cooled to about 3 or 4 degrees cooler when done. I use my mash tun for BIAB so it's used for boiling as well. I've set up a hoist with a strainer above the mash tun so when I remove the bag I place it in the strainer so I can sparge and heat the wort at the same time. The hoist basically acts as another person so I can do it myself. My first batch is currently fermenting so I have yet to see how it turned out. Fingers crossed.

Seems you are making beer,CONGRATZ!!! BIAB is a good way to get started, or hell if your me, it is a good place to end up after a decade of brewing. A few degrees over an hour never hurt anyone or the beer. Take notes, use the notes you take. If I could tell younger brewer me anything, it would be to take notes and use the notes I take.....

T
 
I hated that my mash temps weren't consistent over the hour long mash and I wanted repeat-ability so I made a surprisingly simple mini E-Herms system to do 2 things for me. 1) Recirculate the mash 2) Keep Consistent temps. I already had a pump so I have the mash go from the mashtun, to the pump which sent it to a 10' coil of copper in a small stock pot on top of a hot plate, controlled by an stc-1000 to keep temp. It was a simple and inexpensive solution for keeping mash temp and also producing clear wort.

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Thanks. Yes, keeping notes for sure. Really looking forward to seeing how this first batch turns out. Beats making wine, which I have done, as I won't have to wait a year or more to see how things turn out. Beer is better.:)
 
Thanks. Yes, keeping notes for sure. Really looking forward to seeing how this first batch turns out. Beats making wine, which I have done, as I won't have to wait a year or more to see how things turn out. Beer is better.:)
So... I'd love to hear how the first two batches have gone - show pics if you got 'em!
 
Me too. The first batch has been in bottle for a week so far. So just waiting at least another week. Must resist. Must resist.

The second batch I just made yesterday in fact, finally found some time. The inside of the carboy looks like a hurricane in motion. Very cool to watch. This second batch I could really see the cold break when I was chilling it. Happened between 30 and 35C.

Both are IPA's but this second one is more hop forward and higher in alcohol.
 
So I thought I would follow up as I have now cracked a few pints. Am very happy with my first batch (Super Session IPA), albeit still a little cloudy in the bottle, it has a lovely grapefruit citrus aroma and the taste follows up. Even my wife likes it (not good :(). Once in the fridge the sediment in the bottle hardens up so i can pour the entire bottle without disturbing it. Bonus. As it was my first batch I had a few #$@^& moments, like spilling some of the grain past the bag. No doubt why I have some cloudiness now. Made some changes in the logistics for the second batch and still managed to have a few #$@^& moments, just different ones. Each batch brings me closer to a smooth mash and boil.

Second batch is 2 days into a 4 day dry hop and then to bottle. This one is much clearer. Just tested the SG and it was bang on at 1.015. Not as hoppy, which surprised me, but certainly more mouth feel and a darker colour.

I'm going to do a stout next and hope to have fewer #$@^& moments as I have fixed some of my previous difficulties I guess you could call them. A toast to great beer.
 
In the colder months I use a converted 10 gallon round cooler and seldom see more than 2 degrees drop during a 60 minute mash. I use a heavy towel on top of the MLT and stir twice. During the hotter months I do BIAB and have been playing around with ways to maintain temperature.

Having seen the results of some experiments where tasters couldn't reliably distinguish beers that were mashed at some fairly extreme temperature differences, I'm about ready to just start with an initial temperature 4 to 6 degrees F above what I would normally mash at and leave it alone for 90 minutes when doing BIAB.
 
Bob, that is exactly what I was thinking if I can't keep the temp constant. I now have a wrap for my mash tun and I will keep track as to how much the temp drops over 60 minutes. If it continues to drop 8 to 10 degrees I will start the mash at 4 or 5 degrees above the desired temp and let it fall through the desired temp, ending 2 or 3 degrees below. Maybe it will result in a more complex brew as it will extract some sugars that maybe wouldn't normally get extracted. I don't have a particularly sensitive pallet so we'll see. I'm just keeping records of each batch and what I do so I have a better handle on future batches and what to expect.
 
Don't worry about it too much. Most of the conversion happens early in the mash, before the temperature drops much. In fact, today's base malts can completely convert themselves in 20 minutes.
 
I'm with Nosy. If you start a lot higher than intended then you are converting at that temp versus what you intended to convert at. I'd try hitting the intended mash temp and let it fall.
 
So I thought I would follow up as I have now cracked a few pints. Am very happy with my first batch (Super Session IPA), albeit still a little cloudy in the bottle, it has a lovely grapefruit citrus aroma and the taste follows up. Even my wife likes it (not good :(). Once in the fridge the sediment in the bottle hardens up so i can pour the entire bottle without disturbing it. Bonus. As it was my first batch I had a few #$@^& moments, like spilling some of the grain past the bag. No doubt why I have some cloudiness now. Made some changes in the logistics for the second batch and still managed to have a few #$@^& moments, just different ones. Each batch brings me closer to a smooth mash and boil.

Second batch is 2 days into a 4 day dry hop and then to bottle. This one is much clearer. Just tested the SG and it was bang on at 1.015. Not as hoppy, which surprised me, but certainly more mouth feel and a darker colour.

I'm going to do a stout next and hope to have fewer #$@^& moments as I have fixed some of my previous difficulties I guess you could call them. A toast to great beer.

As long as you are having new and different #$@^& moments, you are on the right track....
 
Great brewers are built on many, many #$@^& moments.
 
I've been doing it for about 16 months now with all grain and I still have those moments. Like pouring a couple liters of sparge water on the floor the other day cause I got distracted.
 

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