How do you measure your mash temperature?

[markq]

Wanted to add my recent experience in, I measured my mash temp the other day with a digital IR thermometer, which I think came just from Amazon (similar to this one Infrared Thermometer -50°C ~ 380°C Non-Contact Digital Laser Infrared Thermometer with LCD Display Precision Digital High Quality Sensor Industrial Temperature Gun:Amazon.co.uk:Kitchen & Home).

I've had strange reads from different surfaces in the past, so was a bit wary about the accuracy of measuring a pan of clear water in a stainless steel pot. That said, I satisfied myself that it was reading okay by boiling the kettle (which is also stainless steel inside). I watched the temp creep up to 98.something as it was at its rolling boil, so I was fairly happy with that.

What I did notice though were huge differences in the temp between different areas of the mash, perhaps unsurprisingly, where the top of the mash was a good 10 degrees colder than the bottom nearer the flame, so without knowing how critical an accurate mash temp is, I'd say constant rotation and monitoring would be key. Even a minute or so undisturbed and differences in temp would be significant.

Also for this reason, I wouldn't be happy with a thermometer fixed to any part of the pot or grain.

 

[An Ankoù]

If your mash is being heated in situ, there will be inevitable temperature variations through the mash. The mash will be at its warmest around the heating element. The clue is in the name; you have to mash it, which means getting a paddle and giving it a good stirring up every five minutes or so until it settles out at your required mash temperature. I don't know about your mash kettle, but if its not well insulated and your heating element regularly cuts in to maintain mash temp, then you have to stir it again, every time. Your thermometers shouldn't be more than one or two degrees different to each other even if they haven't been recalibrated.

 

[Buffers brewery]

If your mash is being heated in situ, there will be inevitable temperature variations through the mash. The mash will be at its warmest around the heating element. The clue is in the name; you have to mash it, which means getting a paddle and giving it a good stirring up every five minutes or so until it settles out at your required mash temperature. I don't know about your mash kettle, but if its not well insulated and your heating element regularly cuts in to maintain mash temp, then you have to stir it again, every time. Your thermometers shouldn't be more than one or two degrees different to each other even if they haven't been recalibrated.

That’s why I prefer to recirculate the wort through a water bath/heat exchanger. I know from experience what temperature to set the water bath thermostat to deliver wort at a couple of degrees above mash temperature so by the time it’s on the grain it’s at the desired temperature. I still give the mash a couple of stirs it seems to work

 

[TimXJR1300]

How would mixing ice cubes with deionised water get 0c? The ice is minus temp.. the water + temp...is there a formula that non clever persons like myself could adopt?

From my 'O' Level Physics.. or possibly Chemistry, When you mix enough ice with water, the water will go to 0C and stay there until all of the ice has melted. Then the water temperature will increase to the ambient temperature

 

[Buffers brewery]

From my 'O' Level Physics.. or possibly Chemistry, When you mix enough ice with water, the water will go to 0C and stay there until all of the ice has melted. Then the water temperature will increase to the ambient temperature

Don’t forget your latent heat! Ice requires lots of calories/joules/or whatever the unit for heat energy is to change state from solid to liquid while it’s temperature remains at zero. It gets those calories from the (warmer) water that’s around it and in doing so the water cools. When you arrive at a state of equilibrium (if you have enough ice and not too much water) you end up with water at zero degrees and ice mixture.

 

[Drunkula]

In case anyone remotely cares, it takes 1 calorie to heat 1 ml of water 1 degree c. To make the state change from water to ice takes 80 calories. So changing water at 20c to ice means you need to ditch 100 calories per ml, while just 80 would boil it. That's why ice in drinks doesn't just melt straight away, it's not just that you have to raise it from -18c or whatever. Tell that story at a party and you'll be fighting off the skirt.

State change from water to steam? 540 calories. So dip your hand in boiling water, ow ow ow, but it takes time for it to conduct heat to your skin. Get steam on your hand and in the state change back to water than 540 calories is delivered in an instant - aye caramba! Está caliente!

Anyone still awake?

 

[Buffers brewery]

In case anyone remotely cares, it takes 1 calorie to heat 1 ml of water 1 degree c. To make the state change from water to ice takes 80 calories. So changing water at 20c to ice means you need to ditch 100 calories per ml, while just 80 would boil it. That's why ice in drinks doesn't just melt straight away, it's not just that you have to raise it from -18c or whatever. Tell that story at a party and you'll be fighting off the skirt.

State change from water to steam? 540 calories. So dip your hand in boiling water, ow ow ow, but it takes time for it to conduct heat to your skin. Get steam on your hand and in the state change back to water than 540 calories is delivered in an instant - aye caramba! Está caliente!

Anyone still awake?

Eloquently put

 

[Buffers brewery]

Calories are non SI units. You need to quote Joules or kW-h or eV even. Not BTU though.

 

[strange-steve]

 

[TimXJR1300]

Was it 4 joules/gram,/ degrees C?

 

[terrym]

Calories are non SI units. You need to quote Joules or kW-h or eV even. Not BTU though.

BTUs are fine if you are from Trumpland

 

[Buffers brewery]

4.1868 J / 0.000001163 kW-h /26132000000000000000 eV / 0.0039683 BTU or there abouts

I'm going to stop now