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Old 01-16-2013, 04:19 AM   #1
orion7144's Avatar
Nov 2012
Cinci, Oh
Posts: 336
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I am considering do a BIAB 10g batch next since the weather is quite cold right now and was curious if it is possible (easy) to say keep the burner on a low setting to keep the mash temp.

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Old 01-16-2013, 04:37 AM   #2
Ogri's Avatar
Sep 2011
Osaka, Japan
Posts: 836
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I suppose it could be possible but many different factors would play into keeping the temp stable and where you want it. Air temp, wind, humidity, burner etc. Wouldn't it be better to rig up/use significant and effective insulation? The thermal mass of the volume of water and weight of grains that you'd have going, to end up with a 10 gallon batch, should hold temp really well if properly insulated. Then again, that might also make it easier to maintain temp with a burner on low, too

Only done stovetop BIAB, 2.5 gallon batch myself and found adding heat as needed, stirring and being very attentive, helped me keep a reasonably constant temp over the hour.

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Old 01-16-2013, 04:38 AM   #3
Dec 2012
Posts: 293
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I have a few biabs under my belt and researched it quite a bit. Some people say you can and not worry about burning your bag. But i took a lighter to a corner of the fabric and it lights off pretty good. I wrap my pot with reflectix wrap and i barely lose a degree in a 60 minute mash. There is a pretty good thread here somewhere that i got it from

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Old 01-16-2013, 05:19 AM   #4
Jul 2012
Seattle, Washington
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Wrap it with a blanket. You can check the temp and give it a stir every 15 minutes or so, but I have some experience with direct fired mashing, and it's REALLY easy to overshoot your temp.
Overshooting the temp is way worse than mashing low IMHO.
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Old 01-16-2013, 05:25 AM   #5
241's Avatar
Sep 2012
San Diego, CA
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Done a couple BIABs at 52 or so ambient temps and had strike water hit 161 for mashing at 154. Hit it on the dot a couple times now and mashed for 60 minutes, checking every 15 with consistent temps.

Only seem to lose 3-4 degrees after 45 minutes, so I light and raise it up a bit. I cover my clad bottom megapot with a blanket. I'd be scared of mashing way too hot if I left the burner on.

I say give it a shot and re-apply heat if you need to.
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Old 01-16-2013, 05:30 AM   #6
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LabRatBrewer's Avatar
Dec 2011
Laguna Niguel, CA
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I wrap it in an old sleeping bag then bungee cord it. Temp stays stable for 90 minutes.

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Old 01-16-2013, 05:55 AM   #7
Feb 2010
Traverse city, Michigan
Posts: 391
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Originally Posted by LabRatBrewer View Post
I wrap it in an old sleeping bag then bungee cord it. Temp stays stable for 90 minutes.
I agree. I do 2.5 gallon biab and wrap my pot in an old comforter and holds temp for 90 minutes

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Old 01-16-2013, 06:06 AM   #8
Nov 2011
long island, new york
Posts: 559
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I pull mine off the burner and place it in the center of an old comforter that I have laid out on the ground. I then wrap it up with the comforter and some towels/ one of my torn Brazilian Jiu-Jitsu gi's. It holds pretty well, but I do lose a couple degrees over the full hour. I've been meaning to get around to the old reflectix trick, but I haven't actually looked that thread up.

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Old 01-16-2013, 06:13 AM   #9
Feb 2011
Brookhaven, Pa
Posts: 244
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Put a small spaghetti strainer at the bottom of the kettle. The bag could rest on it without getting scorched.

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Old 01-16-2013, 12:00 PM   #10
Nov 2010
Solway, MN
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When doing BIAB and adding heat it is really hard to keep from overheating the bottom as the heat doesn't circulate in that mash. You would have to stir constantly to keep it from stratifying and that stirring loses heat then too. It's better to just insulate the mash tun (kettle) better. If your crush is really fine as it should be for BIAB, conversion will happen in 15 to 20 minutes so if your mash cools too far in an hour you might be able to shorten the mash time.

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