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BrewHack

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How do you guys maintain mash temperature with BIAB in a kettle outside? I'm making 5 gallon batches in a turkey fryer and am really struggling with maintaining temperature. I've tried insulating with a sweater and a vest. Temperature drops 1-2 degrees C every 15 mins. I've tried keeping a low flame while stirring, but this is cumbersome and a little scary (worried I'll burn the bag). My efficiency has been low 60s.

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mashpaddled

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Applying more heat or more insulation are really your only options. Do you have a space heater you could use out there? Then you could warm the air and close up the doors with the turkey fryer off.

Kettles are designed to conduct heat so they are always poor vessels (at homebrew volumes) for mashing unless you continue to apply heat. That being said, I don't know how much I would agonize over a four degree drop over an hour. Most of your conversion is occurring in the first fifteen minutes unless you mash with undermodified malts and/or an enormous amount of unmalted grains.
 

RM-MN

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My efficiency has been low 60s.
Applying more heat or more insulation are really your only options.
Third option. Get a cheap Corona mill and get your grains milled properly for BIAB. Your efficiency will go up and the time needed for full conversion will go down, way down. Once conversion is complete it won't matter if you lose heat.

For a full volume, no sparge you should be getting near 80% efficiency. Poor milling will keep that from happening and will require a much longer mash period.
 
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BrewHack

BrewHack

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Thanks for the great suggestions. I've been mashing with the standard 1.5qt/lbs ratio. If full volume mashing can get 80%, I will give that a try. The extra volume of water will slow the temperature drop.
 

RM-MN

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Thanks for the great suggestions. I've been mashing with the standard 1.5qt/lbs ratio. If full volume mashing can get 80%, I will give that a try. The extra volume of water will slow the temperature drop.
You will only get the 80% efficiency with a very finely milled grain so blow your next paycheck on a Corona mill and set it so tight that the milling plates are grinding against each other (not so tight that it is hard to turn). If you hold back a little of the water and at the end of the mash pour that over the bag of grains you will capture more sugars yet, which can push your efficiency higher.

This is the mill that I use. Manual Corn Grinder Flour Maker Wheat Grain Nut Mill Grinder Kitchen Tool | eBay
 

Apple_Jacker

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porterguy

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I use two old sleeping bags and a couple of old rugs wrapped around my BK. You can probably get old sleeping bags cheap on ebay , Craigslist, even garage sales. I brew in temps down to about 30 F. Make sure you wrap ALL around ((I used to not wrap underneath and lost a lot of heat from there in cold weather). I still unwrap one or twice and reheat a bit if I'm worried it dropped too much. The old rugs keep the sleeping bags from melting against a hot burner.:oops:
 

Mr. Vern

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I use an old moving blanket draped over the kettle, using a 15g keggle the blanket almost hits the floor creating a pocket of warm air under the burner. Airflow around/under the pot may be a problem.

Last weeks easy brew:
8 gallon full mash lost 3-4 degrees F in a cold garage over 60 minutes (40-50F room temp. I do not believe the change from 154F to 151F affected the enzymes at all.
 

ATLBeer

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Why not just move it into the house for the mash? You are not applying heat, so the propane isn't an issue.

You are also losing a lot of heat from the bottom of your kettle. Set it on a piece of plywood to insulate.
 

tracer bullet

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Agreed with using a cooler, and pre-heating it too. It's another item to buy and store but it is good for putting a lot of other beer related stuff into when done, and so for me it really takes little additional shelf space if any at all. Sitting it on foam and / or wrapping it with a blanket would help a little too.

Or move it inside, another good option. Could occasionally dump a quart of boiling water into it but not sure I'd bother. If it's inside, perhaps just bump it with some heat every 15 minutes or so combined with some stirring. It won't be perfect but it'll do the job. Perfection will involve new equipment and $'s so of course just aim for good enough for now.
 

brumasterj

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Might I suggest getting a
TAPCRAFT 1500 Watt 120v Heating Element 1/2 inch NPT For Electric Mash Tun HLT Boil Kettle With Weldless Gasket Kit
Then get a inkbird controller!
 

renstyle

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Another vote to do MAIB in an appropriately sized cooler. Sure you may need to swap the spigot, but won't need a false bottom.

I do this. Very simple. Maintains temp for the hour no problem.

Drains easy into the kettle.

It may seem a little backward stepping, but it's safer than a sleeping bag condom on a kettle with intermittent low flame below it! :D:cool:
 

CascadesBrewer

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Anything on the bottom?
No. The bottom is open, though I try to get the bag a foot or so below the pot. A little further down than that the pic I posted. The sleeping bag is doubled over so there ends up being about 3 layers covering the top of the pot. I live in Virginia, but I am sometimes brewing in 30F weather on my back patio. It has worked well for me. I usually warm the bag up in the dryer before use.

Before I moved to BIAB I would put my kettle into an insulated box during the mash. It was based on ideas from Dave Miller's books. The sleeping bag works better though.
 

tracer bullet

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I use the same to pre-heat my mash water right in the cooler. Haven't been brave enough to let it stay in afterwards. However, if you had a dual pot combo (won't be cheap), one inside of another and water in between, you could have this in the outer pot. If that made sense...
 

Tallgrass

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As others mention, wrapping to the floor helps a lot. I use an old king size comforter and lose a degree or two over the hour. Heating the water warms the stand and concrete under. Keep that heat.
 

Spivey24

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I do the refletix double wrap on my kettle. I also switched to using an electric induction cooktop which allows me to apply minimal heat during the mash as needed. This of course is an expensive option, but maybe a simple bucket heater would suffice. Either way you have to stir while heating, or use a recirculating pump. I don’t mind attending a little more to my mash if it saves me cleaning more equipment. (-:
But also a few degrees is not going to change anything perceptively. As a rule, I just start a couple degrees higher in the winter, and accept some decline. I never know the difference in the end.
 
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I did a 20lb BIAB in my 10 gallon kettle yesterday. Mashed in at 150F, wrapped it in a sleeping bag and it went down to 148F after 45 mins. I then unwrapped it, stirred it and it rose back up to 150F for the remaining 45 minutes of the mash. It was around 55F ambient temp in my garage. I was happy that it held temp so well with just a sleeping bag.

EDIT: I guess this is my first post here. HELLO!
 
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Twinkeelfool

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Cheap yoga mat works well but is a pain because you have to remove when you’re heating up and then put back on. I used to get 2c in an hour. Though it’s not exactly cold where I live, it might get down to 10c in winter at worst

Try a mash out to boost efficiency.
 

AZ Maverick

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Another double layer Reflectix user here.
But I mash/brew in my garage so it's usually never colder than 50° to 60° F.
At those temps the double layer Reflectix holds about a 2° F per hour loss.
If it were much colder I'd just toss a sleeping bag over the Reflectix and I think it would hold temp just fine.

Helles_Mash.jpg
 
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BrewHack

BrewHack

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Another double layer Reflectix user here.
But I mash/brew in my garage so it's usually never colder than 50° to 60° F.
At those temps the double layer Reflectix holds about a 2° F per hour loss.
If it were much colder I'd just toss a sleeping bag over the Reflectix and I think it would hold temp just fine.

View attachment 721952
Nice and neat. Does tape cause any damage when you take it off?
 
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I use a double layer of Reflectix and secure it with Velcro strips. I also cut out a piece of plywood the same diameter as the MLT & put two layers of Reflectix on it for the bottom. This helped reduce heat loss even more.
 
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