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Mashing temps

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toddfore

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I have made approx. 10 biab brews and struggle with the mash temp every time. I heat my water to approx 160 for a mash around 152. When I add my grains, the temp drops down to 140. I will then turn on some heat till I hit 150 and put the lid on. I check it every couple minutes to make sure it doesn't spike. Once the temp is stable, I cover with a blanket and check it every 15min or so. Problem is that the temp spikes on me everytime to a point where sometimes it goes over the 160 mark. It's like the grains build temp. Is this the case? Should I just put the grains in 10* higher than my mash temp, put the lid on and let it set for a while? Thanks.

Todd
 
All you need to do is to start using a mash temp. calculator like this one:
http://www.rackers.org/calcs.shtml

Plug in your numbers and it gives you the perfect strike temp, works good for me everytime. Wrap an old coat around the pot and forget about it for an hour.
I got tired of BIAB mash temp problems real quick and got a round cooler to mash in, and still use the BIAB bag in the cooler. Good luck & cheers!!
 
All you need to do is to start using a mash temp. calculator like this one:
http://www.rackers.org/calcs.shtml

Plug in your numbers and it gives you the perfect strike temp, works good for me everytime. Wrap an old coat around the pot and forget about it for an hour.
I got tired of BIAB mash temp problems real quick and got a round cooler to mash in, and still use the BIAB bag in the cooler. Good luck & cheers!!

I BIAB as well and use the above calculator all the time. It hasn't been 100% perfect for me every time, but darn close! I definitely recommend it as well.
 
I can't recommend the above, for BIAB use my calculator! Check it out if you haven't already please. Lots of good features that other biab calculators don't have.

Pricelessbrewing.github.io/biabcalc

As for maintaining temps, I just dough in thoroughly with a whisk and insulate with a bunch of blankets/towels. Usually lose 1-2 degrees.
 
I had this problem using a floating glass thermometer because it was slow to react. I drilled a small hole in my brew pot lid and use a 12 inch dial thermometer. What type of thermometer are you using?
 
I started doing a step infusion because of this issue. Nothing wrong with mashing at 110, 135, 145, 152 etc. depending on beer style. Now I have a better thermometer. Glass thermometers are slow and unreliable same a s the long metal ones from the brew store. I use a laser thermometer from lowes. Just buy a thermometer that gives instant reliable readings.
 
Try holding back 3L or so of your mash water to adjust your mash temp. After dough in, leave it for a few minutes before measuring the temp. If it's low, add some boiling water and stir, if too hot, add some cold water. The addition of hot/cold water shouldn't make the hot spots and 'spike' that heating the pot will.
 
Is saccrification an endothermic reaction? I find that I can hit my mash temp perfectly by using a calculator and stirring in the grains well but in a few minutes the temperature might be a little low in the middle of the mash. If I move the thermometer to the outside edge it will be correct or perhaps a little high.
 
I try to add slowly using a giant whisk, and if I spend more than 5m the temp will drop considerably. I've only made 4 AG batches so I'm still finding the method that works best.

You will have to find what works best for you, take notes, and in the end you will find the method that gives you the consistent results.

You do want to avoid those 160° spikes as that will denature (over time) the very enzymes you want to work in the upper 140°s--low 150°s.
 
I have made approx. 10 biab brews and struggle with the mash temp every time. I heat my water to approx 160 for a mash around 152. When I add my grains, the temp drops down to 140. I will then turn on some heat till I hit 150 and put the lid on. I check it every couple minutes to make sure it doesn't spike. Once the temp is stable, I cover with a blanket and check it every 15min or so. Problem is that the temp spikes on me everytime to a point where sometimes it goes over the 160 mark. It's like the grains build temp. Is this the case? Should I just put the grains in 10* higher than my mash temp, put the lid on and let it set for a while? Thanks.

Todd

Try this. Use one of the calculators mentioned above. Dough in, stirring until all the dough balls are gone. Insulate the kettle. Wait 5-10 minutes, stir one more time and then take your first temp reading. I would wager you'll be spot on next time.
 
Agreed with the above, temp stratification is real. Anytime you take a temperature, be sure to mix thoroughly as there will be regions of hot and cold.
 
Try this. Use one of the calculators mentioned above. Dough in, stirring until all the dough balls are gone. Insulate the kettle. Wait 5-10 minutes, stir one more time and then take your first temp reading. I would wager you'll be spot on next time.

This. Bring the water to 160 (assuming full volume) and add the grains. Stir them in really good and let it sit for 10 minutes and check temp. If it's too high just stir for 5 minutes and let it sit another 10 and see what happens. You'll be amazed how much the temp changes from stirring then comes back up from the mash. It will drop and scare you that you'll lose too much over the next few minutes then you'll see it come up.


You could also just let it sit the full hour and let the thermometer change as the surrounding area changes. Maybe check near the edges and the middle every 10-15 minutes.
 
I do use a glass thermometer. I also have one that attaches to the side of the kettle but lid won't close then. Read that 10 degrees above mash temp is ideal to drop grains in so I will try it next time and wait it out for awhile. Will give one of the calculators a try. Thanks again.

Todd
 
I do use a glass thermometer. I also have one that attaches to the side of the kettle but lid won't close then. Read that 10 degrees above mash temp is ideal to drop grains in so I will try it next time and wait it out for awhile. Will give one of the calculators a try. Thanks again.

Todd

There's really no "rule of thumb" for how much higher you need to be, as it depends on the grain temp, the water portions, how much grain you have, and what mash temp you're doing...

Use a calculator, again I recommend mine. It's simple and has a lot of features others don't.
 
The glass thermometer reacts too slowly. That's why I drilled the small.hole in the lid of my brew pot for the long stem dial thermometer. Wrapped in a blanket I lose less than 1 or 2 degrees an hour.
 
I would be shocked if the long stem dial reacted so much faster and accurately that it was better than the glass floating her meter but maybe I should try both since I have both. Just because it is slower doesn't mean over the 10 minutes you wait it won't be at temp. Try it next time.

I mash in a keggle with no lid. I wouldn't worry about the lid not being on to test both thermometers.

I Mash in 8 gallons for a 10 gallon batch and I didn't see any temperature change after adding grains. The only temp change I saw was when I stirred the mash at 20 minutes then it said the mash was 145 but pre stir it was 158. I hit 70% brew house efficiency that day, dumped everything in the fermenting bucket and I'm sitting on 5.5 gallons that will end up filling a keg nicely.
 
If you under-shoot your mash temp and add heat any delay in the reaction of the thermometer will then cause you to over-shoot. I have had the same experience the original poster had using a foating glass candy thermometer. Probably there are better ones that react much more quickly than mine. Although I consider my glass thermometer to be more accurate it is much slower to react to temperature changes. I use my glass thermometer to calibrate my dial thermometer to 150f but I would not rely on it to make temp adjustments to the mash temp. Put them both in a glass of water and test how quickly they react to temp changes then you'll know.

Not to mention the risk of breaking a glass thermometer in the mash.
 
I used the CDN DTQ450X, $20, accurate and 5-6s response. Allows quick multiple spot check around the BK-used-as-mash-tun. The downsides are the short, 6" probe, and the fact that in my personal experience, the device is **NOT** hot mash water proof (note to self, trying to measure 7" deep into a hot mass will invariably bring skin into contact with said same, with dissatisfying and sub-optimal results).
 
I used the CDN DTQ450X, $20, accurate and 5-6s response. Allows quick multiple spot check around the BK-used-as-mash-tun. The downsides are the short, 6" probe, and the fact that in my personal experience, the device is **NOT** hot mash water proof (note to self, trying to measure 7" deep into a hot mass will invariably bring skin into contact with said same, with dissatisfying and sub-optimal results).

Thermworks has a $20 instant read thermometer as well as the well known one, I highly recommend it over the common $10-20 thermometers. Just like the thermapen, it only needs to be submerged like a half inch to read accurately, and is water proof.
 
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