John Palmer's Mash/Batch Sparge Formulas - Home Brew Forums

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12-29-2009, 08:05 PM   #1
whenindoubtpilsout
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Sep 2009
NYC
Posts: 24
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Hi Everyone,

So I'm finally moving into the wonderful world of all-grain brewing (just built an MLT)... very excited but I have just a few questions so bear with me... any help at all would be greatly appreciated!

(the following equations are from Palmer's "How to Brew")

So I've run through the equations for calculating infusion temp/volume (let's assume a single-infusion mash) and also for revising the grain bill via batch sparge calculations, along with all of the other outputs that come from batch sparge formulas.

The outputs from the sparge calculations include a new grain bill, strike water volume, and water-to-grist ratio.

Do I now go back to the Strike Water Temp formula [Tw=(0.2/R)(T2-T1)+T2] and replace my original values with the new grain bill (lbs.) and water-to-grist ratio? Or do my original calculations still hold?

One more thing: Palmer assumes that a standard (continuous) sparging yields an 80% efficiency, while batch sparging yields 75% (on average). Does this mean that I should calculate my original grain bill at 80% efficiency, then run the batch sparge calculations to get a new grain bill?

Sorry for all of the questions... I feel like I'm taking crazy pills.

Thanks Everybody

12-29-2009, 08:14 PM   #2
ajf
Senior Member

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Oct 2005
Long Island
Posts: 4,646
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For the strike water temperatures see http://www.rackers.org/calcs.shtml, and make sure you have preheated the MLT before you add the grain. Many people add the water about 10 F too hot, and then stir it well. When it cools to the required temp (a few minutes) the MLT will be nicely warmed up.

For your first brew, I would assume about 70% efficiency. Once you have done a brew or two, you can adjust the efficiency up or down to suit your equipment.

-a.
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12-29-2009, 08:24 PM   #3
whenindoubtpilsout
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Sep 2009
NYC
Posts: 24
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Thanks a bunch... so I should calculate my grain bill based on a 70% efficiency, and then let the sparge formulas adjust the bill as such?

12-29-2009, 09:42 PM   #4
whenindoubtpilsout
Recipes

Sep 2009
NYC
Posts: 24
Liked 1 Times on 1 Posts

Answered my own original question... I just had to look at all of the equations, find the common variables, and factor in the water-retention coefficient. Slow work day!

Thanks for the help.