How do you measure your mash temperature?

[JT_Brews]

I'm really struggling with getting temperature readings I trust while mashing.

I BIAB using a Klarstein mash kettle. The kettle has a thermometer which is a nub sticking slightly up from the base next to the heating element. I don't really trust this at all.

I have been suplimenting this with a floating electronic BBQ thermometer with the tip floating about 1/3 down into the mash. I considered this reasonabley trustworth and used this as my primary reading.

However, since these two methods rarely agree (or oddly they tend to agree while heating the water then start to diverge once the element is turned off) I ordered a glass thermometer thinking it would confirm the accuracy of my electronic one.

WRONG. Now I have 3 different temperature readings. At one point I had 70C (kettle), 65 (glass) and 60 (electronic) FFS!

I'd really like to be able to have confidence in my mash temperature so wondered how eveyone else handled this? Is there a more reliable (and waterproof) electronic probe I can buy?

 

[Clint]

With my elbow...
No..I use an Inkbird BBQ thermometer. Then after the mash I use it in the boil kettle.

 

[Gerryjo]

Have you calibrated your klarstein as you can't take for granted those temps and would 2/3 fill with water and check each temp you're looking to use to ensure its correct. I also have an Inkbird BBQ and a few others which are all calibrated on a regular basis.

 

[Clint]

Interesting point in calibration...where do you start?

 

[nixhaz]

How do you waterproof the inkbird probes? Mine goes mental if it gets wet, and then I have to bake it in the oven for a bit to get it to read correctly.

 

[Clint]

I only dip the metal bit...in the BBQ probe it's quite a long metal spike. I secure it to the kettle with a clothes peg.

 

[Gerryjo]

I get my thermometer calibrated twice yearly by a colleague and its a professional kitchen one.
I filled the boiler 2/3 fill and turned each setting until light goes off and stay warm function stays on.
There is a wide range on the start so you can actually set it at 1/2 numbers (1 1/2,2 1/2) and so on. Its doesn't drift much an with the lid on and grain in the temperature may drift 2° on loss and that's dependent on the ambient temperature whether summer or winter.

 

[JT_Brews]

Have you calibrated your klarstein as you can't take for granted those temps and would 2/3 fill with water and check each temp you're looking to use to ensure its correct. I also have an Inkbird BBQ and a few others which are all calibrated on a regular basis.

I can't calibrate but asssuming the offset is constant I could account for it. The real issue is that there is drift between that and the thermometers at the top of the mash. I suspect this is partly from temperature gradient but also that the Klarstein probe is in a poor position right at the bottom.

My electronic one was a fairly cheapo and can't be calibrated so maybe I should upgrade to an inkbird.

 

[Cheshire Cat]

My mash tun has a thermometer gauge on the outside.

 

[Gerryjo]

TBH you would be better purchasing a decent thermometer and calibrate your mashtun as this will give you a more precise temp window.
I assume the Klarstein is insulated and should retain the heat once up to temp but the problem with adding grains without calibration is that the grains act as an insulator giving the built in probe a false indicator of less heat loss than is actually happening on top so when you end up stirring the boi

ler suddenly kicks in and over shoots.
I use one of these and have yet to have it adjusted as its always 0.1 degree in spec at 20 degrees when checked.
I have a few but this is my goto.

 

[Gerryjo]

My mash tun has a thermometer gauge on the outside.

Is it a dial/electronic and how do you know its accurate or is it just an assumption because its factory fitted.
This is part of my job in an industry which is temp critical and we have software linking controllers which cost $2500 each (American Firm) and because of the layers stripped off during processing they build up and cause an insulating layer around the probe which is internal in the soak station so has to be manually checked with offsets applied to compensate for heat loss and this can swing as low as 15 degree's.
Once cleaned this has to recalibrate again as it overshoot but the software doesn't see due to the offset and reads high on the meter when probed and this is why its crucial not to take it for granted even if its only for peace of mind.

 

[Buffers brewery]

A bit simplistic I know but I would be tempted to check the “accuracy” of the different thermometers by making some ice cubes with de-ionised water then mix with some more de-ionised water. When it’s all nicely mixed should read 0 degrees C. Then heat it until it boils and should read 100 degrees C. A bit simplistic as I say but it might give you a bit of an idea which of your thermometers can be believed and of any off-sets to be applied, after all, we are talking about mash temperatures.

 

[Buffers brewery]

I recirculate my wort through a water bath and monitor the temperature of the wort as it returns to the mash tun. Returning wort temperature is displayed on a cheapy digital thermometer
https://www.amazon.co.uk/gp/product/B006918OBQ/ref=ppx_yo_dt_b_asin_title_o09_s00?ie=UTF8&psc=1I check the mash temperature in the tun with a pocket thermometer that is the one I “trust”.
https://www.screwfix.com/p/tpi-digital-pocket-thermometer/82574

 

[Gerryjo]

The whole point of the exercise is calibration and trusting that they are correct.
Try checking with boiling water as well as this will give you your upper and lower variables to allow for offset adjustment.

 

[Benfleet Brewery]

This is what is use: Inkbird ITH-20R Wireless Thermometer Hygrometer Digital Indoor Outdoor Thermometer Wireless Temperature and Humidity Monitor for Greenhouse Reptile Vivarium Wine Cellar, 300ft/90m Range:Amazon.co.uk:Kitchen & Home

I was fortunate enough to get mine free in exchange for a review but I’d have been perfectly happy to pay for it at this price.

 

[Gerryjo]

This is what is use: Inkbird ITH-20R Wireless Thermometer Hygrometer Digital Indoor Outdoor Thermometer Wireless Temperature and Humidity Monitor for Greenhouse Reptile Vivarium Wine Cellar, 300ft/90m Range:Amazon.co.uk:Kitchen & Home

I was fortunate enough to get mine free in exchange for a review but I’d have been perfectly happy to pay for it at this price.

Looks the part and it's great to have remote monitoring...

 

[MmmBeer]

One recommendation would be to give the grain a stir before measuring the temperature. You would normally expect the top layers of a liquid to be the hottest, but in you description, it sounds like the bottom is the hottest (nearest to the element). Also how much water are you using per kilo of grain? A very thick mash would restrict convection, leading to a temperature profile like this.

 

[Gerryjo]

This is why I prefer the catering although the inkbird is within a degree it has actually only dropped to 16 whilst sitting at 17 but this is the ambient temp in my mashtun.

 

[PhilBrew]

Hi @JT_Brews

Can I suggest an alternative approach to calibration, rather than spending ages trying to work out how to measure your mash-temp "accurately" ... pick one of the methods you have for measuring your mash temp, doesn't matter which, just pick one (and stop using the others) ... then brew a batch at a "middling" mash temp (measured by your chosen method) and ferment the wort you produce ... if you feel the FG is too low, mash warmer next time ... if the FG ends up too high, try mashing cooler ... then repeat this method until you get a batch that is "just right"

Whatever temperature you measured that got that "just right" batch, call that 66C ... and whenever recipes suggest mashing warmer or cooler than 66C you can adjust your "just right" temperature accordingly ... you see, repeatability is the important thing in this game, "accuracy" is only important in relative terms (is it accurately reflecting what you did last time), you don't have to be "accurate" absolutely :hat:

Cheers, PhilB

 

[Clint]

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?