How do you measure your mash temperature?

[Hengoedbrewer]

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.

That looks really good. I have a thermapen which didn't need calibrating but I calibrated it anyway; then calibrated my Inkbird 308S probe against the Thermapen. So do you just pop the external probe in for the duration of the mash and leave it be then? would also be handy to do the same to see when wort is cool enough to pitch yeast I guess- I tend to keep washing my thermapen and checking it intermittently which is a bit of a pain.

 

[Cheshire Cat]

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.

Dial attached to a solid probe through a hole into the tun. Came from Powel brewing in North Wales.

 

[MmmBeer]

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?

Ice melts at 0°C, so the liquid water in contact with the thermometer would be at exactly 0°C. Ice has poorer thermal properties than water, so wouldn't interfere with the reading.

 

[Benfleet Brewery]

That looks really good. I have a thermapen which didn't need calibrating but I calibrated it anyway; then calibrated my Inkbird 308S probe against the Thermapen. So do you just pop the external probe in for the duration of the mash and leave it be then? would also be handy to do the same to see when wort is cool enough to pitch yeast I guess- I tend to keep washing my thermpan and checking it intermittently.

I put the external probe in at the start so I know when I’ve reached mash temperature and leave it in to monitor throughout. It then comes out for the boil and goes back in 15 mins from the end when my chiller goes in to sanitise it and I use it to monitor the temperature through the chilling so I know when I’m at pitching temp. I’d be lost without it.

 

[Hengoedbrewer]

I put the external probe in at the start so I know when I’ve reached mash temperature and leave it in to monitor throughout. It then comes out for the boil and goes back in 15 mins from the end when my chiller goes in to sanitise it and I use it to monitor the temperature through the chilling so I know when I’m at pitching temp. I’d be lost without it.

That sounds excellent and a really good piece of equipment for that price- bookmarked on Amazon; thanks for the tip!

 

[Gerryjo]

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?

Mix the ice cubes with water, stir and let sit for three minutes and should give a reading of 0°

Sorry already answered and more scientific too. Good job @Markk

 

[JT_Brews]

...
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

This all sounds a bit too sensible to me, I'll just keep buying more and more thermometers. When I have enough I can use a normal distribution to remove outliers and an average of those that remain will be the one true temperature.

 

[strange-steve]

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?

When ice is put in water the temperature of the ice increases and the temperature of the water decreases, but they will eventually reach an equilibrium of 0° as long as there's still solid ice. That's because the ice temperature won't exceed 0° until it is completely melted. It's a very handy method for calibration.

 

[Buffers brewery]

Ice melts at 0°C, so the liquid water in contact with the thermometer would be at exactly 0°C. Ice has poorer thermal properties than water, so wouldn't interfere with the reading.

“O” level physics c1964. Same goes for boiling (“pure”) water = 100 degrees C :hat:

 

[Clint]

For boiling is that at all altitudes?

 

[KegThat]

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?

I use a fudge thermomter! Very accurate and works perfectly every time. thumb

 

[Buffers brewery]

For boiling is that at all altitudes?

Come on @Clint try to remember your “O” level physics! At 1 bar. Oh the irony!

 

[Clint]

Didn't do physics...

 

[MyQul]

Clint did Alchemy. He's been trying to turn trub into gold ever since

 

[Clint]

Yeah...and mostly a lot of buggering about.

 

[foxy]

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?

The temperature probe which you don't trust, how did you check it?
If the glass thermometer is not a cheap one, you should be able to check the readout from the probe by holding the glass thermometer against the probe. The readout on the screen is indicating the temperature against the probe only. You will have different temperature readouts in various pockets of the mash, no good reading the top of the mash and comparing it to the screen readings.
If there is a discrepancy between the glass thermometer and the screen when you check against the probe, for example +2 C then note it and when setting the mash temperature adjust accordingly.
Insulate the Klarstein, and a good tip, cut a piece of 50 mm Styrofoam so you can sit it on top of the mash, just as if you were mashing in an esky. Laminate the foam with foil and make a handle for it so you can lift it out easily to give the mash a stir every 10 minutes.

 

[JT_Brews]

The temperature probe which you don't trust, how did you check it?

That's a good point and I admit I haven't actually tested it but I will next time I set the kit up. My issue is not just with probe accuracy but also with probe position. I am not confident that the kettle probe being right on the floor of the vessel where the heat enters is a sensible position to give a representative temperature for the whole mash.

And then if I have one in the top of the mash and one at the bottom should I use the average? Or maybe just stir until they match more closely (I don't want to do that much stirring)?

Some of this is navel gazing, I've been making decent beer with the process I have now, but it does bug me and I'd like to be able to replicate mash temperatures consistenly when I remake recipes.

 

[foxy]

That's a good point and I admit I haven't actually tested it but I will next time I set the kit up. My issue is not just with probe accuracy but also with probe position. I am not confident that the kettle probe being right on the floor of the vessel where the heat enters is a sensible position to give a representative temperature for the whole mash.

And then if I have one in the top of the mash and one at the bottom should I use the average? Or maybe just stir until they match more closely (I don't want to do that much stirring)?

Some of this is navel gazing, I've been making decent beer with the process I have now, but it does bug me and I'd like to be able to replicate mash temperatures consistenly when I remake recipes.

Don't worry about the differences in temperature within the mash tun, as long as you stir the mash regularly. The reason the probe is closer to the element is if it was at the top the heat put out by the element will be a lot more. It is during the mash when scorching occurs, believe me their is no better place for the probe than in the vicinity of the element.

 

[Cwrw666]

I use a glass dairy thermometer which is in fahrenheit but conveniently has pasteurisation temperature clearly marked, which just happens to be mash temperature as well. Give the wort a damn good stir first though because different parts of the boiler have widely different temperatures after standing for a while.
BTW the thermostat in the boiler is about 10c innaccurate so a thermometer is essential.

 

[Honk]

I have in the past measured my mash with 3 thermometers and found that it didn't take long to get up to 2 Deg c difference between various probes placed at different points in the mash. Give it a stir and they are back to uniform temperatures.
I guess unless you have a recirculating system then there are going to be differences depending where you measure. I normally just use the one probe but like to give the mash a stir at least 3 or 4 times adding more heat if necessary during an hour long mash.