BIAB Mash Temp consistency

[paul3944]

Completed my 1st BIAB last month and experienced difficulty with attaining a steady mash temperature. Brought the water up to the correct strike temp plus 3 degrees to allow for the grains. Added grains and the temp rose to almost 70c?
I monitored through the the mash (90 min) stirred every 30 mins. I noticed the temp was inconsistent from the centre to the outside of the bag of almost 3 degrees.

Onto my 2nd BIAB. I purchased a Thermapen thermometer to see if the problem lied with the cheap eBay thermometer. Brought water upto strike plus 3 degrees and stirred in and the same as above has happened :twisted:

I'm thinking of fitting a weldless thermometer that will sit below the bag to see if that makes a difference.

Any pointers would be most welcome

Regards
Paul

 

[clibit]

The temperature of the mash will vary from place to place. This is unavoidable, I believe, but is reduced by stirring well, before and during the mash. I nicked this from beerandwinejournal.com:

http://beerandwinejournal.com/walkthrough-mash/

"Stirring helps even out the temperature in a mash and mixes the liquids and solids more thoroughly. If you can manage it, you should always stir your mash at least a few times during the saccharification rest. On a homebrew scale, stirring your mash involves opening up the mash tun, and exposing the mash to cooler environmental temperatures. As such, you will likely need to add heat, or a small amount of boiling water, to bring the mash temperature back up to your target. If you are unable to heat your mash tun directly, and lack the space for a boiling water addition, you will not be able to stir the mash without losing heat. This is not a fatal drawback, however, you may lose some extract efficiency. (And always remember that you can mash in your kettle and transfer to your lauter tun later.)"

 

[paul3944]

Many thanks for the quick reply. I suppose there's not a lot I can do than I am doing already.

Is it possible for the actual temp to rise during the mash?

Regards
Paul

 

[clibit]

Not really, though the temperature can rise after you switch the heat off, as heat is transferred to the grain from the metal and the heat source below if you leave the pot on it. I wouldn't worry - we all face the same issue of mash temperature being a bit uneven. Imagine how that is in a brewery with a huge mash tun. That's why they use a huge mash paddle in microbrewies, to mix the grain in well and equalise the temp as much as possible.

You can stir it, and I would, but we are not talking about something that will massively affect the beer you make. Will you notice the variance of mash temp when you are supping the resultant beer? Just get it as close to target temp as possible and stir it every 20 to 30 mins.