Maintaining Your Biab Mash Temps?

[Crunched]

I did my first BIAB today and found I had to turn my burner on a few times during the 90 minute mash to hold the 66*C.

What is everyone else doing to maintain temp with their BIAB brews? Turning the burner on a few times didn't really cause a problem, it's just that I have read that most people reach their 66*C and then only have to ramp up once later in the brew.

Canberra was really cold today, so that could have something to do with it.

 

[RobB]

I generally only do a sixty minute mash, but I wrap my kettle in a camping mat and don't bother turning on the flame throughout the mash. I lose about two degrees over the sixty minutes which is the same as when I mashed in an esky.

I have tried adding heat through the mash but I kept on losing track of my temperature since I was getting different readings from different spots in the kettle.

 

[wambesi]

I generally only do a sixty minute mash, but I wrap my kettle in a camping mat and don't bother turning on the flame throughout the mash. I lose about two degrees over the sixty minutes which is the same as when I mashed in an esky.

I have tried adding heat through the mash but I kept on losing track of my temperature since I was getting different readings from different spots in the kettle.

Yeah I usually fire the burner up at around the 40min mark for 5mins to bring it back up to temp.
Temp loss is not a huge thing though, it's the first 20mins which is the most crucial.

I also wrap my SS vessel with a camping mat, some days it loses more than others but turns out some fine beer.
I wouldn't worry about it to much.

 

[Thirsty Boy]

If you wrap up your kettle in the mentioned camping mats, or an old sleeping bag or whatever, you should get temp losses comparable to people who are conducting single infusion mashes in eskis - ie a couple of degrees over an hour.

Most people wouldn't stress to much about that - all you need to do is make a few brews and see how the beer is turning out. If its too thin, just start the mash at a slightly higher temperature.

If you are losing more temp than that, or if you are worried, by all means add some heat by turning your burner on. To avoid the differential in temperature that Malty Cultural experienced, you need to stir your mash thoroughly before taking a temperature (I stir mine while I am taking the temperature) - which really shouldn't be an issue, because you should be stirring your mash constantly any time you have your burner turned on anyway.

The 90min mash time is really just playing it very safe - I strongly suspect that 60min is almost always going to be more than enough. After you have a brew or two under your belt, try dropping down to 60mins and see if you are still getting full conversion (iodine test) and if you are - 60 is enough in your system. Then temp loss will be even less of a worry.

You will strike on a method that works for you .. there are just too many little differences in the way people brew for there to be any one "right" way of doing things. Unless you are way off center, it'll work out just fine.

TB

 

[joecast]

to conserve gas and since i brew in the kitchen, i boil up a pot of water and add that a couple of times through the mash to raise temp when i need. also i dont have my total water volume from the start so i also add some boiling water at the end of the mash to help get to boiling temp in the kettle.
joe

 

[Crunched]

Cheers for the tips guys.

 

[reviled]

I normally put a rug and a sleeping bag wrapped around the kettle, the rugs only there so that the plastic material the sleeping bag is made out of doesnt melt. It works really well, maybe 1 degree drop in an hour...

And to ramp up to different temps, I tried starting out with a smaller volume of water and adding boiling water to bring up to mash out temp, and what do you know, my efficiency went up :huh: God knows why, but it did... So ill probably do that again...

 

[RobB]

To avoid the differential in temperature that Malty Cultural experienced, you need to stir your mash thoroughly before taking a temperature (I stir mine while I am taking the temperature) - which really shouldn't be an issue, because you should be stirring your mash constantly any time you have your burner turned on anyway.

I think my problems came from my use of a thick bottomed stock pot as my vessel. The base is somewhere between 1 and 2 cm thick and soaks up a lot of heat from the flame, which it then transfers to the mash for several minutes after the flame has been extinguished.

During my first few BIABs I was convinced that I had the temperature correct. However, when I came back in a few minutes to stir the mash, the temperature would jump up significantly as I stirred the lowest part of the grain bed upwards.

I now leave my kettle for five minutes before adding the grain, to give the base time to radiate it's heat. The combination of 30kg of thermal mass and 12mm of foam gives me all the stability I need. For step mashes I start with a lower volume and just dump in extra hot water.