Cooler Mash Tun Target Temperature

[ishkabibble]

My cooler mash ritual is as follows:

- Add 180F water to tun (1.25Q/#), close lid for 10min, wait for water to hit 169F.
- Dough in 10-12# of 65F grist, stir, cover for 10 min

After 10min my digi-thermometer reads different areas of mash as being anywhere from 149 to 161. Even additional stirring and closed-lid waiting don't help to equalize the pocket temps. I'll shoot for 152 or 154, and get the aforementioned 12-degree spread.

After 20-odd all-grain brewings, this has been my consistent experience. I should mention I've never had a problem with conversion or gravity.

I'm just curious, do people actually hit a homogenous target temperature, and if so, how?

What am I doing wrong?

 

[Newsman]

(snip)

I'm just curious, do people actually hit a homogenous target temperature, and if so, how?

What am I doing wrong?

Maybe they recirculate the mash water??? I don't know. I've only done one all-grain, and I screwed that up royally (didn't really sparge much and added a LOT of water to the boil, so I really screwed it up! )

 

[CA_Mouse]

What type of cooler and capacity? I made mine from a 52-quart eXtreme Coleman blue rectangular cooler. I have been getting really good results with it and routinely test it for issues. I tested it last week between batches by filling it with cooling water run off. Filled it with 124*F water and 14 hours later when I went to brew it was at 117*F. Specific circumstances are that it was warm from the brew day, filled with hot runoff water and left in the tub over night.

 

[Yooper]

Yes, I do get an even temperature throughout.

Here's how I do it, though- just like your technique except that before I cover the MLT and walk away, I stir thoroughly. I check the temperature throughout, and if they are different, I stir some more. I stir until the temperature is equalized throughout within a degree or so (I have an instant read thermapen) and THEN I cover it and walk away for an hour.

I lose about 1 degree in an hour in the cooler MLT and it stays the same temperature in every place once it's thoroughly stirred.

 

[wilserbrewer]

Yep, as Yoop said, stir, wait and stir more! I takes more waiting and stirring than one would think to achieve a uniform temp throughout the mash.

 

[SpeedYellow]

I get roughly 2F spread with a digital thermometer throughout the mash period, regardless of stirring. This is yet another reason I gave up on the digital thermometer, in favor of the glass lab thermometer, which reports more of an average temperature due to its response time.

 

[signpost]

Besides patience and persistence in stirring like Yooper suggested. The only other thing that could effect an evenness of mash temp is how thick the mash is. The 1.25 quarts per pound of grain that you mentioned is pretty normal. But if you up it to 1.5 quarts per pound of grain, you might have an easier time getting the temp even throughout the mash.