Musing on creating a System DO Metric
Posted: Wed Jul 20, 2016 7:42 pm
With much of what I have read, and measured between the GrainFather and the Brew-Magic, it seems that perhaps it is possible to create a metric that defines the potential DO ingress of the system.
My thinking is this (the numbers are wags): Assume the water is pre-boiled, chilled too grain-in temps, and moved over for grain-in. Say this liquor is 0.5 ppm DO, plus an average of 4.5 ppm DO uptake during mash-in, resulting in a 4 ppm DO variable (MI). Let's assume a 60 minute mash period, with mash cap, that results in an additional 1.5 ppm DO uptake (MP), so now we are at (MI + MP) or 5.5 ppm DO uptake. Let's then assume a 45 minute lauter, gently under a floating mash cap, and estimate another 2 ppm DO uptake from the lauter and gentle drain into the boil (L). So (MI + MP + L) result in a potential 7.5 ppm DO take up. We could use the System DO profile to more carefully tailor any SMB/AA/BrewTanB additions. We could also measure knock out uptake, and have a very small dose to add to the chilled wort before moving it into a fermenter. I made up the DO values - so ignore that, they are there for conversation sake.
Variables would require careful measurement of each process, and repeatability or automation of moving wort or liquor. It seems that the total grist weight should also be a variable, perhaps as a slope to increase or decrease the MI value. I am trying to think of other possible variables. Temperature? Rate of circulation?
Any merit here? Seems like Big Monk may already have some of this in the spreadsheet?
My thinking is this (the numbers are wags): Assume the water is pre-boiled, chilled too grain-in temps, and moved over for grain-in. Say this liquor is 0.5 ppm DO, plus an average of 4.5 ppm DO uptake during mash-in, resulting in a 4 ppm DO variable (MI). Let's assume a 60 minute mash period, with mash cap, that results in an additional 1.5 ppm DO uptake (MP), so now we are at (MI + MP) or 5.5 ppm DO uptake. Let's then assume a 45 minute lauter, gently under a floating mash cap, and estimate another 2 ppm DO uptake from the lauter and gentle drain into the boil (L). So (MI + MP + L) result in a potential 7.5 ppm DO take up. We could use the System DO profile to more carefully tailor any SMB/AA/BrewTanB additions. We could also measure knock out uptake, and have a very small dose to add to the chilled wort before moving it into a fermenter. I made up the DO values - so ignore that, they are there for conversation sake.
Variables would require careful measurement of each process, and repeatability or automation of moving wort or liquor. It seems that the total grist weight should also be a variable, perhaps as a slope to increase or decrease the MI value. I am trying to think of other possible variables. Temperature? Rate of circulation?
Any merit here? Seems like Big Monk may already have some of this in the spreadsheet?