Mash and Lauter Simulator Available

[doug293cz]

I have made my Mash and Lauter simulator available here.

This spreadsheet works for both batch sparge and no-sparge (sorry fly spargers), and traditional MLT or BIAB. It can be used to predict SG's, lauter and mash efficiencies, mash volumes, etc. And if you download it as an Excel or LibreOffice sheet, you can use the "Goal Seek" tool to do things like:

• Calculate conversion efficiency from first runnings SG or pre-boil SG
• Calculate grain absorption rate from strike volume and pre-boil volume
• Calculate boil off rate from pre-boil volume, post-boil volume and boil time
• Use your imagination

Accepts both Imperial (gallons and pounds) or Metric (litres and kilograms) measurement units.

Input fields have blue backgrounds.

I'll be adding more info here in the future on how to use and inner workings. In the mean time, play with it and make any comments or suggestions in this thread.

Edit#1: I describe the calculations used in this spreadsheet here.

Brew on

 

[harten74]

Doug, Thanks so much for the time you put into this awesome simulator and for sharing the fruits of your labor with the HBT community! I have a couple of questions for you...

1. In the Analysis section, in a BIAB system, would "Total Weight of Remaining Mash" be the weight of the spent grain and retained water once it is lifted from the MLT? In other words, the weight of the hoisted bag minus the weight of the actual bag itself.

2. Would you please explain the difference between Apparent Grain Absorption and True Grain Absorption?

3. Would you please explain the difference between the Post-Boil Gravity (SG) and Post-Boil Gravity (SG) [Rigorous Calculation]?

Thanks so much!
Clark

 

[doug293cz]

Doug, Thanks so much for the time you put into this awesome simulator and for sharing the fruits of your labor with the HBT community! I have a couple of questions for you...

1. In the Analysis section, in a BIAB system, would "Total Weight of Remaining Mash" be the weight of the spent grain and retained water once it is lifted from the MLT? In other words, the weight of the hoisted bag minus the weight of the actual bag itself.

Yes - after all of the draining/squeezing is completed. The bag will weight considerably more when it is first pulled out of the mash vessel, and get lighter as wort drains.

2. Would you please explain the difference between Apparent Grain Absorption and True Grain Absorption?

Apparent Grain Absorption Rate (in gal/lb or L/kg) is defined as (Strike Water Volume - (First Runnings Volume + Undrainable Volume)) / Grain Weight. Apparent grain absorption rate is the value you need to figure out your total brewing water requirements as follows:

Total Brewing Water = Pre-Boil Volume + Undrainable Volume + Apparent Grain Absorption Rate * Grain Bill Weight​

However, apparent grain absorption isn't really how much water was actually retained by the grain, since the total volume of wort (collected + retained) is more than the total brewing water volume. This is because the extract (sugar, proteins, etc.) adds volume to the wort, and the collected wort volume is greater then the volume of water in the collected wort. That means that more water was absorbed by the grain than the value of Apparent Grain Absorption Rate * Grain Bill Weight. True Grain Absorption Rate is a calculation that tells you how much water was actually absorbed and retained by the grain, and is always higher than the apparent grain absorption rate. True grain absorption rate has no practical value that I know of, but was included in the speadsheet just for the nerdiness factor (someone asked about it.)

3. Would you please explain the difference between the Post-Boil Gravity (SG) and Post-Boil Gravity (SG) [Rigorous Calculation]?

The non-rigorous Post-Boil SG is calculated using the gravity point method, which is an approximation (usually a very good approximation.) The Rigorous Post-Boil SG is calculated by determining the Plato of the post-boil wort (based on the weight of extract and weight of water at the end of boil), and using a formula that converts Plato to SG. The conversion formula takes into account the non-linearities in the SG vs. extract concentration relationship. The gravity point method does not account for the non-linearities.

Thanks so much!
Clark

Hope this helps more than confuses.

Brew on

 

[harten74]

Hope this helps more than confuses.

Brew on

It absolutely does. Thanks again!