Mash out strike water help

[porter1974]

This weekend, I am brewing a robust porter (13.75 lbs grain) and a mosaic IPA (13.5 lbs of grain). I want to get the strike temp right on the mash out. The mash out for both will be at 170 degrees. The first infusion goal is 152.

My last beer was a blonde ale. It was 10.5 lbs of grain. I hit the first infusion temp at 154. That was a few degrees higher than I wanted but no biggie.

The problem was in the mash out. I wanted to hit 170 degree but only hit 162. I added 5 gallons of water at 180 degrees to the 154 degree grains in the mash tun.

Is there a way to calculate what temperature the strike water should be for the mash out? I figure the water volume for the mash out will be about 3.5 gallon but won't really be sure until I draw off the water from the first infusion.

 

[beermanpete]

John Palmer's How to Brew website has the formula and instructions for calculation the volume and temperature of water additions for step-mashing and mash-out here: http://howtobrew.com/book/section-3/the-methods-of-mashing/calculations-for-boiling-water-additions

Here is an excerpt with the formula:

Initial Infusion Equation:
Strike Water Temperature Tw = (.2/r)(T2 - T1) + T2

Mash Infusion Equation:
Wa = (T2 - T1)(.2G + Wm)/(Tw - T2)

where:
r = The ratio of water to grain in quarts per pound.
Wa = The amount of boiling water added (in quarts).
Wm = The total amount of water in the mash (in quarts).
T1 = The initial temperature (¡F) of the mash.
T2 = The target temperature (¡F) of the mash.
Tw = The actual temperature (¡F) of the infusion water.
G = The amount of grain in the mash (in pounds).

The infusion water does not have to be boiling, a common choice is to use the sparge water at 170¡F. Then TB becomes 170 ¡F and more water (Wa) will be needed to make up the additional quantity of heat.

 

[doug293cz]

Are you batch or fly sparging? If batch sparging (or no sparge) there is no need to mash out.

You should be using boiling water (not 180° water) to do an infusion mash temp step, and a mash out is just another temp step. There are many calculators that will do infusion step calculations. Here is one.

Brew on

 

[dmtaylor]

Use boiling water.

 

[porter1974]

I am batch sparging.

 

[porter1974]

Are you batch or fly sparging? If batch sparging (or no sparge) there is no need to mash out.

You should be using boiling water (not 180° water) to do an infusion mash temp step, and a mash out is just another temp step. There are many calculators that will do infusion step calculations. Here is one.

Brew on

I did use the brewer's friend calculator to calculate the initial strike temp. I can't really figure out the mash out portion though.

 

[porter1974]

Use boiling water.

I love this response. Mathematical equations make me feel sick to my stomach!

 

[homebrewer_99]

I use 200F water for batch sparging.

Long story short...I used a center punch to mark wort volume on the side of my boil pot. I record the wort volume from the initial draw. This amount is subtracted from my desired pre-boil volume to tell me how much sparge water I need to use.

 

[doug293cz]

I did use the brewer's friend calculator to calculate the initial strike temp. I can't really figure out the mash out portion though.

Fill in the top section ("Initial Infusion") with the details of your mash. Then go to the lower section ("Additional Rests / Infusions") and put your desired mash out temp in the box on line 2.

Brew on

 

[porter1974]

Thank you for your help.