Beginners Mashing Problem

[mattco353]

Hi,

After what I thought was a good amount of preparation on converted keg mash tun and boil kettle I recently did my first AG brew. I didn't want to use additional heat in the mashing process and made a nice tight fitting Poli Iso insulation jacket for mash keg (4" thick) which completely encloses it and it seemed to work very well when tested with water. (approx 1.5 dec C loss per hour). I was dismayed however to lose 12 deg C during the mash (strike water entered at 70 deg and I ended up at 58) and it was very difficult to raise the temp by adding a kettle of boiling water. My grain bill weighed approx. 10 pounds. Presumably the heat capacity of the grain was my problem? Before I redesign system, how advisable would it be to use a much higher strike temperature, say 80 - 85 deg. Advice always welcome.

 

[Reelale]

I would suggest Beersmith. It will calculate your strike water temperature based on your equipment. All you do is enter the parameters. It has been extremely accurate for me. There is a trial version at beersmith.com. And the full version is worth every penny.

 

[nilo]

Each system is different, but definitely needs the strike water hotter than you mash temp since both grain and tun will cool the water.
How did you calculate that your strike water should be 70C?

 

[ILuvIPA]

+1 Beersmith being worth every penny. With free download you can't lose.

You might also check out pg 170 "How to Brew" by John Palmer. Also worth every penny, also available for free trial (most city public libraries have a copy.) Palmer's equation for manually calculating intial strike water temp is:

Strike water temp = (0.2/R)(T2-T1) + T2
where: R=ratio of water to grain in qut/lb or liter/kg; T2=target temp of mash; T1=initial temp of mash (grain)

Palmer gives additional equations in the book, eg: Quty of water @ a specific temp needed to raise a given mash a specific # of degrees (step mash.) I've found both Beersmith & Palmers manual equations to be very accurate in my converted picnic cooler.

 

[impur]

Just to add to whats been said i like to put 3 or 4 cups of boiling water into my MLT to bring up the temp inside there before i add my grains or strike water. A few min later i add the strike water, test the temp, and add the grains. Helps avoid that initial drop in temp.

 

[ajf]

Try http://www.rackers.org/calcs.shtml.
Saves you having to download and install anything.
This calculator assumes that you have pre-heated the mash tun to the required mash temperature before adding the strike water and grains.
Most people do this by heating the strike water hotter than necessary, adding it to the mash tun, and waiting till the mash tun warms up, and the strike water cools. A little experimentation will be necessary to determine how much hotter the strike water needs to be.
Don't believe anybody who tells you that the water should be x degrees hotter. x varies according to whether you are using C or F scales, and the material that you mash tun is made of.
As an example if this, refer to ILuvIPA's response. I'm sure it works for him, but if you are using metric measurements, the 0.2 needs to be be changed to 0.41 He is also using a plastic mash tun while you are using stainless steel. The thermal mass of SS is greater than plastic, so you will need to use hotter water than he does to get the same results.

Hope this makes sense.

-a.

 

[mattco353]

I would suggest Beersmith. It will calculate your strike water temperature based on your equipment. All you do is enter the parameters. It has been extremely accurate for me. There is a trial version at beersmith.com. And the full version is worth every penny.

Thanks for that, Beersmith has been downloaded

 

[mattco353]

+1 Beersmith being worth every penny. With free download you can't lose.

You might also check out pg 170 "How to Brew" by John Palmer. Also worth every penny, also available for free trial (most city public libraries have a copy.) Palmer's equation for manually calculating intial strike water temp is:

Strike water temp = (0.2/R)(T2-T1) + T2
where: R=ratio of water to grain in qut/lb or liter/kg; T2=target temp of mash; T1=initial temp of mash (grain)

Palmer gives additional equations in the book, eg: Quty of water @ a specific temp needed to raise a given mash a specific # of degrees (step mash.) I've found both Beersmith & Palmers manual equations to be very accurate in my converted picnic cooler.

Perhaps I'm beyond help....I have the book! Using the formula the strike water should have been 74 deg C and perhaps I also should have followed impur's advice re preheating. (I did pre heat but not with boiling water and perhaps for too short a time). Hopefully a combination of improvements will eliminate problem on next batch. Thanks all.