Mash Out Water Calculations Way Off

[johnwpowell]

I mash in a 10 gallon cooler. I always hit my mash in temp with Beersmith calculations. I find that hitting the mash out temp with near boiling water using the calculations is way off. I would say that I end up adding double or more to the point my 10 gallon cooler is almost full for a 5 gallon batch. What gives? Should I abandon mashing out? I can't make the water any hotter.

 

[Silver_Is_Money]

Most people skip the mash-out step these days. But if you want to continue doing it, try using the mash calculator at Brewer's Friend. Remember to input the nominal temperature at which water boils for your altitude. For me this is 209.6 degrees F., as I'm at 1,200 ft of elevation above sea level. I believe the ballpark rule of thumb is to deduct 1 degree F. (from 212 degrees) for every 500 feet above sea level.

https://www.brewersfriend.com/mash/

 

[RM-MN]

Unless you are fly sparging a mash out isn't needed.

 

[Chanoc]

The way I see mash out is to set desired beer profile so it deoesn't change during the time it takes the wort to reach denaturing temps.
With this said, mash out with as much water as posible and start heating first runnings if you Can.
Conversion is not that fast once you approach deneturing temps anyway,
So you should be OK.

 

[dmtaylor]

Mash-out for batch spargers is totally unnecessary. Skip it.

 

[IslandLizard]

None of the calculators have an input field for incurred heat loss while you're stirring with the lid off. I tend to lose 2-3 degrees F each time I open the (rectangular) cooler and stir for 1 minute. That's indoors with a 5.5 gallons batch of 1.060-1.070 and a water/grain ratio of 1.5. In cold or breezy weather that loss would be higher.

For the same reasons, when mashing in I need to add 6F (!) to my calculated strike water temp to compensate due to the longer stirring period with the lid off.

I also lay a double sheet of heavy duty aluminum foil right on top of the mash before closing the lid, to reduce heat loss to the headspace.

Now the need for a mashout depends on many factors. If you want highly fermentable wort, a mashout is not needed, or even recommended. The longer time the enzymes are active the better. If you want to reduce fermentability, a mashout is only needed if your lauter is slow, you can't start heating the (first) runnings right away or it takes a significant time to reach 170F (large volume, slow burner, etc.).

If I want to do (serious) step mashes I mash in the kettle over direct but low heat (induction plate, tri-ply bottom kettle) and constant stirring while heating. After a final 10' mashout at 168-170F I dump the whole lot into the cooler mash tun for lautering and sparging.

 

[TravelingLight]

TIL: I have no idea what a mash out is. I always thought that's what I was going when I drained to the kettle!

 

[IslandLizard]

TIL: I have no idea what a mash out is. I always thought that's what I was going when I drained to the kettle!

Search in your browser:

mashout​

Or if you use (Google) Chrome browser and you want returns from HBT only:

site:homebrewtalk.com mashout​

 

[TravelingLight]

Search in your browser:

mashout​

Or if you use (Google) Chrome browser and you want returns from HBT only:

site:homebrewtalk.com mashout​

TIL how to google!



Just kidding. Thanks brother.

 

[johnwpowell]

I do fly sparge

 

[pricelessbrewing]

None of the calculators have an input field for incurred heat loss while you're stirring with the lid off. I tend to lose 2-3 degrees F each time I open the (rectangular) cooler and stir for 1 minute. That's indoors with a 5.5 gallons batch of 1.060-1.070 and a water/grain ratio of 1.5. In cold or breezy weather that loss would be higher.

Added to my to-do list...