BIAB Temp Control

I've been reading threads about BIAB brewing for months and haven't seen anyone mention this technique so I thought I'd share. Sorry if it's here somewhere, I just haven't seen it.

Temperature control while mashing is an inherent challenge in BIAB brewing. Adjusting temperature of the mash by applying heat directly to the mash pot creates a hotspot at the bottom of the kettle and trying to maintain a constant temp is a pain in the ass without wrapping in blankets and even then it's not uncommon to have a 3-5 degree difference in temp across the rest period.

Anyway... if you happen to have 2 different sized kettles so that one fits inside the other, I highly recommend using them as a double boiler. This not only insulates the mash kettle with a surrounding layer of hot water but it also protects the mash kettle from direct heat should you need to apply heat for temp adjustment.

I just finished a 90 minute mash of 10 lbs of grains with this method and basically set it and forgot it. The temp didn't change a bit over 90 min and when it was done, I pulled the mash pot out of the larger pot and heated the larger pot to 170 in 10 minutes for a 10 min dunk sparge.

Hope this helps other BIAB brewers out there. Again, if this is info that is already out there, I apologize for the redundency.

Cheers!
TM

I use a keggle, no issues. Guess it's due to the volume.

+1, very resourceful solution.

I would try it if I could, unfortunately in my case a 16qt pot is the biggest thing I have right now. I only do three gallon batches so maintaining temps is even trickier with the smaller volume.

My workaround is slightly similar to yours, which has been to have a second smaller pot of water on the stove sitting at around 190-200F. Heat to strike temp, kill the heat and mash in as usual, and if I experience any temperature loss (I do) I mix in some of the hotter water a small amount at a time to maintain mash temps. It's a little more involved, but it works. And since I usually "sparge" after the mash I already have a heated pot of water ready to go, same as your technique!

I just did a batch yesterday in a 10 gallon stainless steel pot (I used a different BIAB set-up previously).

I fashioned Reflectix wrap (thanks to other posts for the idea) so that there were 4 layers surrounding the pot and did something similar for the lid. But both of these are removable and the part surrounding the pot I secured with velcro after wrapping the pot - something I saw on another thread.

So, I heated the water to strike temperature, placed the pot on the floor on towels, THEN easily wrapped the pot with the Reflectix wrap I had made, put in the bag, doughed-in and covered it with the Reflectix-covered lid.

My initial mash temp was 153.7 and it fell to 153.5 at the end of a 90 minute mash. Then I just unwrapped the pot and I was good to go.

It was the first time I used this particular BIAB set-up but it's hard to believe the results. Same as a dedicated mash tun.

I use a turkey fryer, directly heated, and use the blanket method. I still have to check it and usually re-heat it up every 20 minutes or so to maintain the temperature.

ayoungrad said:

I just did a batch yesterday in a 10 gallon stainless steel pot (I used a different BIAB set-up previously).

I fashioned Reflectix wrap (thanks to other posts for the idea) so that there were 4 layers surrounding the pot and did something similar for the lid. But both of these are removable and the part surrounding the pot I secured with velcro after wrapping the pot - something I saw on another thread.

So, I heated the water to strike temperature, placed the pot on the floor on towels, THEN easily wrapped the pot with the Reflectix wrap I had made, put in the bag, doughed-in and covered it with the Reflectix-covered lid.

My initial mash temp was 153.7 and it fell to 153.5 at the end of a 90 minute mash. Then I just unwrapped the pot and I was good to go.

It was the first time I used this particular BIAB set-up but it's hard to believe the results. Same as a dedicated mash tun.

Click to expand...

This method sounds great. I'll have to look into the Reflectix wrap. Nice to have for keeping fermentors warm, too. I always like multipurpose when I can get it.

When I biab, I wrap the kettle in an old sleeping bag; only loses a couple degrees over 1 hr.

I usually stick my kettle in the oven and that seems to keep the temperature steady. Depending on your mash thickness you might want to adjust the oven temperature though. For thick mashes, I usually set the oven to 180 degrees and for thinner mashes, I set it at about 200. This method keeps the temps steady for me.

I mashed a Hefe at 152 yesterday. Wrapped my kettle in two shipping blankets, basically one wrapped around the top and bottom, and one wrapped around the sides, with a bungee holding it all together.

60 minute mash in the sunshine on a windy 68 degree day in central FL.

Temps held at EXACTLY 152 for the entire 60 min mash. Probably not possible at much lower ambient temps, but here in FL, the blanket mash is much simpler than all of the other acrobatics listed above.

TopherM said:

the blanket mash is much simpler than all of the other acrobatics listed above.

Click to expand...

usually works great, especially if the kettle/tun is filled to the max. for smaller mashes, i notice the temps swing a lot more, and do two things. either start the mash a tad thick, that way you can add boiling water to keep temps, or put it in the oven at the lowest setting, 170 for me. on a good day, i tend to keep a 60 min mash within a degree or two of mash temp.

Here's my electric rig. I also use Reflectix (4 layers). Holds temp great and I just bump a burners for a minute or two every 20 or 30 minutes when it is REALLY cold.