BIAB - Maintaining Mash temperture

Blackmuse

Blackmuse

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Okay, so the only thing that is really bugging me about BIAB is: worrying over my mash temperature. Here's the deal: I get all sorts of different temperature readings when I move the thermometer and grains around. The most consistent temp I get is when I leave it smack dab in the middle of the grains. I assume that is where I should leave it...? However, when it does drop enough and I attempt to raise the temp it takes longer than anticipated and I worry I am raising the temp too high...

NOTE: I live in New Hampshire and brew outside with a propane burner. Day temp yesterday was 66 and when I brewed last night it was 38!

FOR INSTANCE: Middle of grains the reading went from 150 to 146 so I went to raise the temp but it was cold out (outside burner) and in ten minutes I am only up to 148 but when I stirred and moved the thermometer around I found readings on the side, where there isn't so much grain, that read 170! Seriously.... Which to believe?

Maybe I am answering my own question here but:
I feel that I have had better luck when I am not constantly trying to maintain my mash temp. I hit my mash temperature and then I wrap and cover my pot (off the burner) and let it do it's thing - only stirring 2-3 times over the mash period.

Can anyone confirm or debunk any of this rambling? Is it simply a "situational - New Englander" thing?
Don't worry about hurting my feelings - I just want a answer to the question and maybe some tips on how to fix it. :)

Thanks!
 
I screwed up 3 batches using a probe thermometer, the kind you stick in your pork loin. I never moved it around the pot, but I always maintained the temperature where I wanted it, 152°, for example. I think most of the mash was a good 10° warmer than that. That resulted in some very malty brew that finished about 10 points higher than expected. I switched to a floating thermometer and read it after stirring thoroughly, and my brews are fermenting out completely now.
 
good reason to get a pump, recirculate over the top to even out the tempature
 
Thank you for the feedback. I doubt I'll rock a pump as I want to try and keep things simple. Maybe one day when I build a brew "shed".

I think I will try a floating thermometer as Jeff mentions. I too am using a probe thermometer at the moment.

Again, thank you for the tips. Any others are definitely welcome.
 
only way to keep the temperature even without a pump is stir at least every 15 minutes
 
Ozarks Mountian Brew said:
only way to keep the temperature even without a pump is stir at least every 15 minutes
Click to expand...

This I did the other night but it was colder than usual (for May) out and I found that I lost temperature way faster than if I had left it covered. I may change my wrap around pot though and use a sleeping bag instead of the towel I usually use. This should help some.

I can definitely see the advantages of a pump but am still not sure if I want to invest in something like that...
 
The simple answer is a better insulated mash tun.
Stirring during the mash isn't necessary if you're maintaining temperature and or not trying to change it.
When I used to brew at home in the winter, I always brought my mash tun inside. At least it was consistently 70°.
Have you considered just putting your bag into a cooler?
Another idea would be to put your brew pot into a warm oven.
There are many options. Experiment and see what works for you.
Brian
 
The Brew Mentor said:
The simple answer is a better insulated mash tun.
Stirring during the mash isn't necessary if you're maintaining temperature and or not trying to change it.
When I used to brew at home in the winter, I always brought my mash tun inside. At least it was consistently 70°.
Have you considered just putting your bag into a cooler?
Another idea would be to put your brew pot into a warm oven.
There are many options. Experiment and see what works for you.
Brian
Click to expand...

I have brought it inside before and that did work well. I probably should have done this the other day too. The warm oven sounds like an even better idea! So should I warm the oven and turn it off or keep the oven on between 100 - 150?
 
If you oven goes low enough to maintain your mash temp, that's perfect. Mine doesn't.
My BIAB set up is only for 2-4 gallon batches but I set a timer and stir every 10 minutes until temp on the outside is close to temp on the inside. I mash in a regular kettle myself. I add heat usually every 20 minutes, so 3 about times through out the mash. When it drops about 2-3 degrees is more like when I add heat. I just like doing it this way with BIAB ¯\_(ツ)_/¯
 
Right on. My oven will hit 150. The only issue I can see is that there is some plastic on my handles - I wonder what temp that would start softening/melting/burning at?

Then again I am in the market for a bigger brew pot - any recommendations? I like my pot short and stocky.
 
Blackmuse said:
The Brew Mentor said:
The simple answer is a better insulated mash tun.
Stirring during the mash isn't necessary if you're maintaining temperature and or not trying to change it.
When I used to brew at home in the winter, I always brought my mash tun inside. At least it was consistently 70°.
Have you considered just putting your bag into a cooler?
Another idea would be to put your brew pot into a warm oven.
There are many options. Experiment and see what works for you.
Brian
Click to expand...

I have brought it inside before and that did work well. I probably should have done this the other day too. The warm oven sounds like an even better idea! So should I warm the oven and turn it off or keep the oven on between 100 - 150?
Click to expand...

The closer to the Mash temp the better, but if your oven is heated to, lets say, 180° and then shut off, it'll keep everything perfect. After hitting your strike temp, just put it in there and leave it alone. go take a nap for an hour!
Good luck,
Brian
 
another way is to create a RIM's system for your brew pot. there are many sites that show how to make a RIMS tube.
I use an electric brew pot that is monitored with a PID and the wort is circulated from the bottom to the top of the brew pot. this way the temperature is always kept at the temperature you set the PID.
this system is 120v, 20 amp with a 2000 watt hot water heater. I must admit that I do put it on my stove to help raise the temperatures faster and boil better.
 
I stir it and wait a minute before checking the temp. I have been doing BIAB just like you do for a while now. I move the thermo around too to get a average idea. The one thing I learned that really helped though is my strike temp is never more than 4 degrees higher than the temp I want to mash at. It is easier to bring the temp up than get it down and I barely miss my mark now using room temp grains at around 10 to 12 pounds. Once I am at the right mash temp I cover the kettle with a heavy blanket and stir every 30 mins and check temp again. I always mash BIAB for 90 minutes. So far that has worked for me. BIAB has its limitations but I can keep a temp within 4 degrees or less this way.
 
Funny you mention stir and wait a minute before you check. I brewed yesterday with a friend who was interested in the process. I had already told him that you have to stir and wait, because the initial reading would be off. I pulled the lid, and started to stir. He immediately grabbed the floating thermometer. I told him he was wasting his time. He said he just wanted a rough idea. He said I was way off my 149°, at 144°. I told him to wait a minute. I checked again, and I was at 149°.
 
Just like cooling your beer its has cooler and warmer wort mixed together,when You stir it equalizes but it doesn't happen immediately
 
The temperature change is all but immediate. It's the thermometer that needs time to adjust!
 
Heisenberg's Uncertainty Principal tells us that the very act of measuring the temperature, effects the reading, so in fact your temp reading is a reflection of the effected temp, not the actual temp.

That being said, and with full knowledge that this effect would be minimal to the point of unnoticeable, I will say:

Mix well, and cover with a blanket/ insulating device, and the temp drop over an hour is a minor enough difference, that the final beer will be fine.

This is the very reason I use a analog thermometer, as all I got to do is get the needle in the vicinity of the correct temp and I'm good. Those digital bastards will drive you crazy.
 
GernBlanston said:
Heisenberg's Uncertainty Principal tells us that the very act of measuring the temperature, effects the reading, so in fact your temp reading is a reflection of the effected temp, not the actual temp.

That being said, and with full knowledge that this effect would be minimal to the point of unnoticeable, I will say:

Mix well, and cover with a blanket/ insulating device, and the temp drop over an hour is a minor enough difference, that the final beer will be fine.

This is the very reason I use a analog thermometer, as all I got to do is get the needle in the vicinity of the correct temp and I'm good. Those digital bastards will drive you crazy.
Click to expand...

I do worry a lot less when I just let it ride! And my digital bastard is what is driving me crazy! LOL. Note taken.

Thanks for all the advice folks! I am interested in trying the oven method and if not then at a minimum I will keep it inside and covered during the colder periods here in NH.
 
jeffpn said:
The temperature change is all but immediate. It's the thermometer that needs time to adjust!
Click to expand...
I wasn't very clear, sorry but my point is you might have more cooler wort that warmer so getting your target temperature can be slow, thats why its best to stir until all readings are within 2 degrees then cover and leave it, otherwise it might equalize cooler rather that warmer
 
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