First AG batch and question about reading mash temp

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bsdx

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I embarked on my first AG batch today after 25-30 extract and it was a success. I made a procedural writeup beforehand with notes where I should try to watch my numbers so I could guide it back on course if needed. After a bit of a rocky start I ended up with 5 gallons in the bucket at my desired OG for BM's Ode to Arthur so I can't complain. Some of my temperatures dropped fairly rapidly at a few stages so my attenuation might be high but I was aiming for a dry finish anyway.

I was doing BIAB using a 12 gallon rectangular cooler for the mash and my brew kettle for the sparging. I preheated my cooler and used beersmith to calculate my water volumes and temps to try to hit mash in and mash out temps. Long story short I had a little thermometer malfunction thrown in but the mash temperature was not even in all places, it varied a lot depending on where I checked. I had other thermometers and tried to get it under control but wasn't pleased with the readings I was getting, so I decided to stop trying to adjust the temperature and leave it be. Threw the lid on and a blanket on top (the lid seems not to have any insulation as I discovered during testing yesterday), and had a homebrew while the mash was converting. I was pretty sure I was in a range that would still make beer, and later iodine tests, tasting, looks etc confirm that very much ;) But is there a better way to get a solid mash temp when doing BIAB? Does the liquid temp matter, I assume only the part where the grain is since that is what is getting converted mostly? Am I supposed to stir the heck out of it to get a solid reading while hoping the whole time that I'm not way off? I'm kinda glad I didn't have direct heat involved this time, I would have gone bananers. I'd imagine you'd have similar problems with any other non-recirculating setup. Thanks for any input. :tank:
 

Got Trub?

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You have to stir your mash really, really, really well. This will break up all the dough balls and get you a much more even temperature throughout your mash tun. I also wait about 5 minutes after mixing to check the mash temperature. Be sure to keep detailed records and you will be able to dial in your mash-in temperature to within a degree of target consistently.

GT
 

aphid_rancher

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I had a similar experience this weekend and am also trying to figure out how much to stir and how to properly measure temperature.
I found the temperature varied a fair bit in different spots in my MLT (and even in the pot of water while it was heating). I was reluctant to stir too much however because I was worried about heat loss and messing with it too much. How much temperature variation is reasonable after stirring the mash and letting it sit for, say, 10 minutes? Should I stir and check the temperature a few times or just let it go? I want both good beer and to know how I am doing.
 
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