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Author Topic: Digital Attenuation Calculation  (Read 834 times)

Offline Rbalsinger

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Digital Attenuation Calculation
« on: December 13, 2020, 03:01:29 pm »
I did a "Digital Attenuation" search of this forum which produced zero. If there is a related thread somewhere please direct me.

I am reading Yeast. ; The Practical Guide to Beer Fermentation White & Zainasheff - Brewers Publications - 2010. On page 108 there is a discussion of "apparent attenuation" and "actual attenuation". Great series so far. I am sure it does not need my recommendation but has it without reservation.

In late December or early January I am expecting the arrival of a PLAATO v.3 hydrometer. I am thinking about the claim made by the manufacturer on promotional material:

By knowing the rate of CO2-release, we also know how fast alcohol is produced.
If we know the total volume of CO2 released, we also know the total amount of ethanol produced and gravity.


Is there any fact (or speculation) regarding this claim? Do you think that a "calculated attenuation" might be closer to "actual attenuation" than "apparent attenuation"? I understand that one argument might be "it is all relative" and I agree. ie: Distance does not change when it is measured in inches or centimeters, but knowing the reliability of those two systems, is that a fair association?

Not into rocket science but there must be factors related to bubble size and pressure.

My question then, is real attenuation more accurately described by a calculated attenuation based on bubble count or by apparent attenuation via traditional hydrometer? I am personally (at this point) without experience of using digital, but the convenience and usefulness of the data captured has sold me. Ballpark measurement is fine, but I am curious about the forum's consensus.

I thought about paying my 9-year-old grandson to count bubbles. ;D

Off thread, I am returning to brewing after a 25-year hiatus (long haul trucking). I first brewed in the late 70's and then again in the 90's. Each setup was better than the previous one, but I am excited about this latest effort. We are 85% finished setting up. Pam's knees are waiting for replacements and she has no plans of going downstairs ever again. So, I got access to the whole finished basement and furnace room. I am thinking of a combo man cave / Lab / Brewery.  ;D Getting some new bits and pieces together and hope to brew New Year's Eve day. When I finish with the setup, I will post pics and details of the setup, hoping to get some advice and peer review any mistakes in the planned process. I was an AHA member in the 90's and am thankful for the opportunity to be back.


Offline lupulus

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Re: Digital Attenuation Calculation
« Reply #1 on: December 13, 2020, 05:27:42 pm »
Short answer is neither.
Assuming it does a great job, it will measure gas produced, which is directly related to CO2 production and thus alcohol production. From alcohol, it will calculate apparent or real attenuation by formulas.

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Offline Rbalsinger

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Re: Digital Attenuation Calculation
« Reply #2 on: December 13, 2020, 05:38:30 pm »
Cool. Thanks. The data capture for logging will be valuable at the loss of nothing except $$.

Offline BrewBama

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Digital Attenuation Calculation
« Reply #3 on: December 13, 2020, 06:58:02 pm »
... I was an AHA member in the 90's and am thankful for the opportunity to be back.

Welcome back. I look forward to seeing your setup as it evolves.


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