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Mash Temperature Adjustment

BeerSmith

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Some people have found that their mash temperatures were a bit too high or too low when using BeerSmith with the "Adjust Temperature for Equipment" flag set.

One way to remedy this is to go into your equipment profile and make sure your equipment settings reflect your actual equipment.  See the following FAQ for more information on setting your equipment:

http://beersmith.com/equipment_setup.htm

In addition, you may need to adjust the "Mash Tun Specific Heat" setting depending on the material of your mash tun.  For example, though stainless steel has an average specific heat of about 0.120, it can vary quite a bit higher or lower than that depending on precise steel type.

Plastics, in particular, have a lot of variation.  Your specific heat could be as low as 0.25 or as high as 0.4 or even 0.5 depending on plastic type.

Unfortunately there is no easy way to precisely narrow down this parameter other than to make small adjustments if you come out a bit too high or low on a particular batch.  You can always have a small amount of cold and boiling water on hand to adjust the termpature a bit until you have found your ideal equipment settings.

Cheers!
Brad

 
Brad,
Isn't there a way to do a reverse calculation to figure out the actual specific heat of your mash tun?

Lee
 
If you happen to know your precise infusion temperature for a given recipe you can input the recipe and then adjust the specific heat to match it.

Once you have this number you can enter it into your permanent equipment profile and use that for future recipes.

Note that the default specific heats are good starting points - you need only adjust them if your temperatures are off significantly.

Cheers!
Brad
 
Brad,
I am still having trouble with this , I believe all my equipment settings are correct.
My mash temperture comes out as 70C , I want to mash at 64C.
Is there a way to simply change the 70C to 64C ?
I would like to set this as default

Cheers Batz
 
Batz,
 There is no direct way.  You could try lowering your equipment setting (Mash tun specific heat) to get it to match or try running a batch without the "Adjust temp for equipment" flag set.

 Your temperature difference seems quite large (6C is quite a bit) so you might also want to test your thermometer to make sure it is not off.  It is unusual to have the temperature hit so far off on the high side.

Cheers!
Brad
 
I must be something wrong here Brad

I have the " Adjust temp. for equip." flagged , now I can adjust my specific heat from 0c to 10000c and the mash or strike temperture  does not change in my recipe

Batz
 
Batz,
 The target mash temperature will stay the same, but the temperature of the water to add for the infusion will change.  This shows up in the mash steps and also on the brewsheet.

Cheers!
Brad
 
Thankyou again Brad,
Now it is the target temperture that I would like to change , 70c is too high for me.
Is there someway I can reduce this?

Cheers Batz
 
Hi Batz,
If I understand you correctly all you need to do to adjust target temp is,
open your mash profiles from main menu, double click on the mash profile you want to use, then double click on the mash step you wish to adjust, then adjust the step temp for your target temp that you require and Beersmith will do the rest.

If I have misunderstood what you were asking I apologose.

Cheers
Andrewqld
 
That's it ! ;D

I don't know why I couldn't see that looking at me in the face.  ???

Thanks for all your help guys

Batz
 
OK, so my numbers were off and after reading here I have a question about getting more accurate numbers after you pick the specific heat number for your mash tun.  I have very well insulated kegs as my tuns and can now perfectly control my HLT, so if I have accurate numbers for my MT I should be right on.  I went with my original Stainless Steel numbers of .120 and my newly weighed weight of 40 lbs for my first batch post-upgrades.  I was way off so I went back and adjusted my mash rest temperatures to reflect what I got during the session.  I then changed my Specific Heat number until the temperature of my infusion water was what I actually got during session.  So, I got my brewery relatively close now and I am wondering.  Which number makes more since to skew to make my actual numbers during a session match up?  I did a little experiment before posting and found that at each increase or decrease by 1 lbs at the same specific heat number was only .3 degrees difference in my infusion water temperature.  The same infusion water temperature difference held true when I kept the same weight and changed my Specific Heat of MT number by .01 higher and lower.  So, which number makes more since to skew and which one should I leave alone?  Does it matter which one I skew?  As the programmer, I ask you since you know which one plugs into the program in more detail.  I am glad I got the numbers to match as close as I did, and it will take a couple of more sessions to know how to tweak.  I just thought I would ask so I can get to it.  Thanks Brad, and hope to hear from you soon.
 
Hi,
  I've always adjusted it by changing the specific heat number, but I suppose adjusting the weight would be equivalent.

  Obviously the stainless steel number assumes stainless steel as the main material.  If it is well insulated you will likely achieve a much higher specific heat for the system.

Thanks,
Brad
 
Is there any way to reverse calculate the specific heat? I mean... if we start with boiling water and subtract the temp of the water after we put it in the mashtun and wait 60 minutes... something of that nature?
 
Hi,
  I can't think of a quick way to do this.  The actual formula is pretty complex.  Generally I recommend starting with the "plastic" specific heat and then adjust it a bit if you are off.

VR
Brad
 
I took the advise from a fellow brewer who told me to set the Mash Tun Material on the aluminum setting even tho mine is an Igloo Cooler. It has been pretty close for me. As long as I heat up the MT prior to adding the grains. If you still have a large variance you could change it to SS.

Hope this helps.

Preston
 
This a fairly old post but a significant one addressing a number of basic and relevant issues.  Attached is a spreadsheet I've used for years that addresses the issue of adjusting a missed mash temperature "on the fly" as well as finding the specific heat of a mash tun.  Both are derived from the basic equation at the top, the "Mother of All Brewing Thermodynamic Equations."

For adjusting a missed strike temperature I keep a gallon of pre-chilled water in the refrigerator and another gallon at or near boiling. I use one or the other depending on whether I'm over or under on the temperature.  Fill in the basic parameters, measure the temperature of the water adjustment addition, and it will calculate the numbers of ounces to add.  Quick, simple and foolproof.

As for calculating the specific heat of a mash tun, you simply use a variation of the basic equation.  I recently built a new tun around a 5 gallon Gott cooler.  I added measured amount of strike water, let the temperature stabilize for about 10 minutes and then measured the water temperature.  Entering this value into the spreadsheet results in a specific heat of 0.35.  Subsequent brew days confirmed the accuracy of the result.

For the geeks I've included the equation derivations.  For the mathematically challenged, simply fill in the necessary cells.

Hope this helps.  Enjoy.


 

Attachments

  • Mash Temp Adjust.xls
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