# BIAB - How do you guys measure your Mash Temp

### Help Support Homebrew Talk:

#### brennanj11

##### Well-Known Member
Hey Guys,
How do you measure the water temperature while doughing-in?
I usually start about 4 degrees higher than my desired temperature, cut the heat, dough-in, stir like crazy, lid and cover w/ blanket.

My thermometer is the Chef Alarm from Thermoworks, not sure if it made for water temps, but I get hot spots and difficulty relying on the temperature, as I assume it might be hotter where the grain is opposed to where the probe is on top of mash.

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#### Oginme

##### Well-Known Member
I have the chef alarm also. Went through a few dead probes before getting one of the long probes. This reaches well into my kettle when I do BIAB and also my mash tun when I do larger batches.

Anyhow, I stir in the grain for about 5 to 10 minutes, the higher the gravity the most I stir. Then I stick the probe in about 2/3 of the distance from the center to one of the edges and measure the temperature there. This seems to represent the temperature of the majority of the mash pretty well.

In terms of strike temperature, I have BeerSmith pretty well tuned into my process and seldom end up more than a half of a degree away from target.

#### Brew_G

##### Well-Known Member
I use pricelessbrewing's calculator to determine strike temp. I dough in - stirring the whole time - and then measure my mash temp as soon as all grains are in the kettle. At that point, I either keep stirring (if temp needs to come down a bit), leave it be (if my temp is spot on), or hit the heat for some short time (if mash temp is low). If I hit the heat, it's for no longer than about 30 seconds (depending on how much higher I need the temp to get), and I stir the entire time so as not to burn the bag.

OP

#### brennanj11

##### Well-Known Member
I have the chef alarm also. Went through a few dead probes before getting one of the long probes. This reaches well into my kettle when I do BIAB and also my mash tun when I do larger batches.
How do I find these, how long is it?

#### Gavin C

##### Well-Known Member
Like this after ensuring everything is well mixed and fully stabilized.

OP

#### brennanj11

##### Well-Known Member
Like this after ensuring everything is well mixed and fully stabilized.

I was more talking about a continually monitoring of the temp during the mash.
I know my system pretty well, and have had consistently good mashes, but I brew outside.

#### Gavin C

##### Well-Known Member
My pot also has a dial thermometer but is more indicative of stability rather than a mash-temp I trust.

How I monitor satbility now.

This is how I used to measure temps and stability.

The polder thermometer's probe is in the mash. The wire snakes out under the lid and out the insulation.

#### AnOldUR

##### fer-men-TAY-shuhn
If you want to check mash temperature other than just at the top, get one of these.

#### Gavin C

##### Well-Known Member

That is one cool bad-ass looking small footprint RIMS setup. Class. I'm jealous big-time.

#### AQUILAS

##### Well-Known Member
I have the Thermoworks RT600C thermometer and use a Coleman Xtreme cooler as my MLT.

After getting my strike temp, I dough in, stir really well, and once I reach my mash temp, leave the lid closed for the entire hour. So far, the cooler stays within 1F of the mash temp. At first, it was kind of a "have faith" type thing, but now I know my cooler is consistent with maintaining heat.

#### Todd820

##### Well-Known Member
I BIAB as well and will check on the temp 1-2 times during my 75 minute mash depending on the external temps. I could probably hold the temp better if I used better insulation. For the moment, just a couple of towels/blankets. I usually end up dropping 1-2 degrees every 30-40 minutes so I correct mid mash.

#### skitter

##### Well-Known Member
I do 2.5g batches, so usually 5lb of grain. I start the water at 160, grain drops it to 150, wrap the pot in a blanket with a towel under it, and put my military camo jacket over that... Usually at 148 by the end of 60 minutes.

#### pdxal

##### Well-Known Member
If you want to check mash temperature other than just at the top, get one of these.

Tell us about that set up, I'm intrigued.
Is the pot sitting on an induction burner? Which one, and what power/wattage? Tell us about the RIMS set up you have.

#### slym2none

##### "Lazy extract brewer."
I measure temp from a few places in the pot, even after stirring well. Instant-read thermometers are really nice for that!

#### AnthonyUK

##### Well-Known Member
I use a PID controller to get to strike temperature as it is 'fire and forget'.
After mashing in I leave it connected but disconnect it from the heating element so I can monitor the temp drop.

#### Nickyssix

##### Well-Known Member
I use a mad millie cheese making thermometer - strike temp 3-4c higher than mash temp - dough in, mix up gently - take the temp on 4 corners and in the middle - adjust with hot or cold water - once my mash hits temp the lid goes on and ive never needed to adjust it - stays the same for 90 minutes if thats what i'm after.

#### AnOldUR

##### fer-men-TAY-shuhn
Tell us about that set up, I'm intrigued.
Is the pot sitting on an induction burner? Which one, and what power/wattage? Tell us about the RIMS set up you have.
The induction hub is a Avantco 3500W. I only use it for boiling. I tried using it for mashing, but even with recirculating, I wasn't happy with the control it gave me over mash temperature. The RIMS tube was made mostly from stuff I had; 3500W/240V element leftover from another project, a piece of stainless tube I found in the shop, CPC disconnects from a big lot I bought from someone here on HBT who was switching to stainless. I run it at 120V, so 875W and adjust the heat with a router speed control. It's under powered for doing step mashes on its own. I use infusion to get me close and then the RIMS tube to get me the rest of the way and hold the temperature while continuously recirculating.

I built the RIMS tube with no real plan in mind. Read about them and just wanted to see if I could. There was no place for it in my three vessel system, but to keep things interesting, I've been doing some BIAB's and it's worked great for that.

#### Yooper

##### Ale's What Cures You!
Staff member
Mod
Like this after ensuring everything is well mixed and fully stabilized.

Me too. Except my thermopen is pink. And my arms aren't quite so hairy. Other than that, just like that!

I stir like I mean it, until the temperature is the same throughout (love the instant read!) and cover. I have a HERMS, though, so once I dough in my temperature doesn't change.

#### kh54s10

##### Supporting Member
HBT Supporter
I don't have a decent way of controlling the temperature during the mash so I just stir very well ensuring I have it as consistent throughout as I can, then, if it is in my 5 gallon pot (3 gallon batch) I put it in my pre-warmed over for the hour. If I did a bigger batch I wrap it in blankets and again just leave it for the hour.

I do the same with my cooler mash tun in my 3 tier rig. Stir well, close it up and wait!

#### Gavin C

##### Well-Known Member
Me too. Except my thermopen is pink. And my arms aren't quite so hairy. Other than that, just like that!

I stir like I mean it, until the temperature is the same throughout (love the instant read!) and cover. I have a HERMS, though, so once I dough in my temperature doesn't change.
Got the green one during a Paddy's day sale. There alwas seems to be some sort of sale of various colors. I signed up for their emails and bided my time. Love my Thermapen.

OP

#### brennanj11

##### Well-Known Member
I have the Thermoworks RT600C thermometer and use a Coleman Xtreme cooler as my MLT.

After getting my strike temp, I dough in, stir really well, and once I reach my mash temp, leave the lid closed for the entire hour. So far, the cooler stays within 1F of the mash temp. At first, it was kind of a "have faith" type thing, but now I know my cooler is consistent with maintaining heat.
I BIAB as well and will check on the temp 1-2 times during my 75 minute mash depending on the external temps. I could probably hold the temp better if I used better insulation. For the moment, just a couple of towels/blankets. I usually end up dropping 1-2 degrees every 30-40 minutes so I correct mid mash.
Me too. Except my thermopen is pink. And my arms aren't quite so hairy. Other than that, just like that!

I stir like I mean it, until the temperature is the same throughout (love the instant read!) and cover. I have a HERMS, though, so once I dough in my temperature doesn't change.
Hey guys, these quotes are starting to sound like a pattern

To summarize some consensus
When you first start at BIAB...dough-in, stir like crazy, take temp and insulate. Taking into account mash time and external temperature, measure the temperature drop before mash-out. This will give you a good baseline for your system's insulation capability: if the drop is do great, improve the insulation or maybe store in a warm oven during the mash.

Then once you have your set-up insulation efficiency under control, you dough-in, take temp and either add hot/cold water or stir or briefly heat under heating element.

Sounds like once you can rely on your process and system, it sounds like measuring mash temp during the mash is pointless.

#### Yooper

##### Ale's What Cures You!
Staff member
Mod
Hey guys, these quotes are starting to sound like a pattern

To summarize some consensus
When you first start at BIAB...dough-in, stir like crazy, take temp and insulate. Taking into account mash time and external temperature, measure the temperature drop before mash-out. This will give you a good baseline for your system's insulation capability: if the drop is do great, improve the insulation or maybe store in a warm oven during the mash.

Then once you have your set-up insulation efficiency under control, you dough-in, take temp and either add hot/cold water or stir or briefly heat under heating element.

Sounds like once you can rely on your process and system, it sounds like measuring mash temp during the mash is pointless.
And, preheat your vessel when you start. Even though I mash in a keg, I start with 180 degree water and cover it and let it drop to my strike temp (usually around 165 or so). If you're mashing in a stainless pot, preheating does help since cold metal "sucks" the heat out of your water. I was surprised how well my keg did maintain heat once I preheated it. I had been mashing in a cooler and preheating that, and didn't expect the keg to maintain the temp as well as it did. Yes, it will drop by the middle of the mash if you don't insulate it, but if you preheat, stir well, and then insulate you should be fine.

The first few times, have some ice cubes on hand and some boiling water just in case you miss by a lot at dough-in. Don't sweat a degree or two, and just stir to equalize and give it some time. After that, if you're way off, you can add a little boiling water or a couple of ice cubes, stir well, and check again. Once again, give it time to equalize.

#### bbohanon

##### Well-Known Member
Smaller 5 gallon cooler batches that I still do separate from my e-HERMS setup, I always strike about 15deg higher than target temp. I would rather strike high, stir a little more/longer and add cold water if needed to bring it down. Striking low means more hot water to bring it up.
I use a Thermopen for these batches as well to dial in the mash temp.

On my 10 gallon e-HERMS, its all automated via PIDS and thermocouples so its set it and forget it while recircing/sparging.

I usually only brew smaller 5 gallon cooler batches if I have some sort of experimental batch or if I just feel like doing a small batch on a weeknight.
It is also nice to go back to the old cooler method from time to time just because.
:fro:

#### Gavin C

##### Well-Known Member
Of course with BIAB and single vessel brewing the mash-tun can be assumed to be at the same temperature as the strike water as you are heating strike water in the tun directly unlike a three vessel system where the hot water from the HLT will lose heat to the MLT once it enters it.

SS is a great conductor of heat. Just be sure to tell whatever software you are using that it's a stainless steel mash tun and it's temeperature is the same as strike (with single vesel brewing)

In beersmith in the mash-profile the tun temperature and grain temperature can be entered. In the equipment profile, the weight and material of the tun can be entered.

Feed it all the right data and it's a very accurate tool.

#### AQUILAS

##### Well-Known Member
it sounds like measuring mash temp during the mash is pointless.
Early on, I was told that continuing to open and close the mash tun to check temp will only result in heat loss, which will lead efficiency loss. I took that to heart and played around with my cooler mash tun before actually doing my first mash in it. The first test run, heated up 5 gallons of water to some high temp and just tossed it into the cooler. I checked temp every 20 minutes and after the 60 minute mash, I lost about 10F. Made sense because heat was escaping whenever I opened the cooler. The next run, I heated up 5 gallons of water. Once the water got to about 150, I dropped in a gallon to prime/preheat the mash tun, and then tossed the rest of the water once it hit my target temp. I just left it alone for the entire hour and that's when I struck gold. I only lost about 1F.

When my first brew day came, I did exactly as the second run, and it stayed true. It actually helped with efficiency because the recipe I used was set for 65% and I actually hit about 70-71%. So this is how I'll be doing my mash from now on.

#### balrog

##### Supporting Member
HBT Supporter
Like this after ensuring everything is well mixed and fully stabilized.
What do you budget for dough in time, how long would you estimate that to typically be, with say 11# grain?

Oops, never mind. Found your other post explaining just my question here.

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#### Doed

##### Belching Dog Brewery
Stir real well. First use this Therma_K, then attach the PTFE/FEP TIP PROBES Model: 113-372/373/375-T and place it into the mash with the Therma_K resting on the pot lid.

#### jahdub

##### Well-Known Member
I use pricelessbrewing's calculator to determine strike temp. I dough in - stirring the whole time - and then measure my mash temp as soon as all grains are in the kettle. At that point, I either keep stirring (if temp needs to come down a bit), leave it be (if my temp is spot on), or hit the heat for some short time (if mash temp is low). If I hit the heat, it's for no longer than about 30 seconds (depending on how much higher I need the temp to get), and I stir the entire time so as not to burn the bag.
I do it exactly like this. I use a thermapen.

I never make adjustments to the temp during the mash. The temperature tends to only drop a few degrees over 60 minutes. The few experiments I've seen on here seem to indicate that most conversion occurs within the first few minutes, anyway. Doesn't make any sense to me to go to great lengths to maintain mash temperature.

Hey Guys,