VFO when jusing a Hop sock

• • SVA Brewer With Over 50 Brews From Australia
  • Quote
• • • 0
    • 0
    • 0
    • 0
    • 0

• • SVA Brewer With Over 100 Brews From Great Britain
  • Quote
• • • 0
    • 0
    • 0
    • 0
    • 0

Hi Mally, I use pellets.

Until today it wasn't something I even thought about as I previously threw all the hops loose into the boil. However first time today used a hop Sock and set the BIABacus for Advanced Trub management. So I can see BIABacus adjusts my SWN which makes sense, just on the recording side of things and how I should measure I'm uncertain. On top of that it was a Hop heavy brew so a lot of trub was in that sock.

So now not sure if I should pull my "Teabag" and measure or leave it "floating"

• • SVA Brewer With Over 50 Brews From Australia
  • Quote
• • • 0
    • 0
    • 0
    • 0
    • 0

[NOTE: Make sure you are using latest BIABacus versions so as terminology matches the below. Also see Clear Brewing Terminology.]

Mally's answer, as usual , is correct bundy. And, as he also said - good question.

This is one of those things where we can easily over-think things. Adding even 200 grams of hops really does not add any significant volume to the kettle so we don't need to worry about that side of things at all. And all hops stay in the kettle until after flame-out no matter what you do so VFO - Voume at Flame-Out will always include your hops.

What does change on a more hoppy/less hoppy brew is your KFL - Kettle to Fermentor Loss. The pre-release BIABaci, like all other commercial software, promote the myth that gravity and hop weight do not affect your KFL. In other words, they pretend it is a constant. In the first official release we have an improvement on this but it can't be perfected without introducing macros into the spreadsheet.

...

There is also a downside to this 'perfection' as it can lead new brewers to think that all these estimated volumes and gravities are god-like whereas, no matter how good the programming, a brewer should experience considerable (but not worrying) variations from the estimates. Pro brewers learn to understand what variances are worth worrying about and how to correct for these on each batch. Amateur home brewing software, sites and forums tend to sell the illusion of consistency and repeatability. In other words, if your numbers aren't matching the estimated numbers then you are doing something wrong.

...

VFO is actually quite a hard number to measure. For a start, wort at boiling point shrinks and swells wildly. It also reduces in volume much faster from say 100 C to 90 C than from 50 C to 40 C. Also, if you have an immersion chiller, that causes a displacement (unlike your hops .

VFO is at best a safety check, a double-check. If you no-chill, slow-chill, or use a counter-flow chiller or plate chiller, take the measurement. If you use an immersion chiller, don't bother.

...

For the purpose of 'accurate' measuring, if you did pull the hopsock before measuring 'KFL - Kettle to Fermentor Loss', then the hopsock should be dumped into a bucket and after the kettle to fermentor (or cube*) transfer is completed empty the hopsock back into the kettle and measure the KFL.

And that is what I thought would be a short answer ,
PP

* If no-chilling into a cube, KFL becomes even more complex to measure as the cube trub needs to be measured as well. However, if you do a careful transfer to cube, then cube trub will be negligible.

• • SVA Brewer With Over 100 Brews From Australia
  • Quote
• • • 0
    • 0
    • 0
    • 0
    • 0

PistolPatch wrote:[NOTE: Make sure you are using latest BIABacus versions so as terminology matches the below. Also see Clear Brewing Terminology.]

Mally's answer, as usual , is correct bundy. And, as he also said - good question.

VFO - Voume at Flame-Out will always include your hops.

What does change on a more hoppy/less hoppy brew is your KFL - Kettle to Fermentor Loss. The pre-release BIABaci, like all other commercial software, promote the myth that gravity and hop weight do not affect your KFL. In other words, they pretend it is a constant. In the first official release we have an improvement on this but it can't be perfected without introducing macros into the spreadsheet.

...
...

VFO is actually quite a hard number to measure. For a start, wort at boiling point shrinks and swells wildly. It also reduces in volume much faster from say 100 C to 90 C than from 50 C to 40 C. Also, if you have an immersion chiller, that causes a displacement (unlike your hops .

VFO is at best a safety check, a double-check. If you no-chill, slow-chill, or use a counter-flow chiller or plate chiller, take the measurement. If you use an immersion chiller, don't bother.


For the purpose of 'accurate' measuring, if you did pull the hopsock before measuring 'KFL - Kettle to Fermentor Loss', then the hopsock should be dumped into a bucket and after the kettle to fermentor (or cube*) transfer is completed empty the hopsock back into the kettle and measure the KFL.


PP
.

Thanks PP, For me I do use an Immersion Chiller but to date have always measured and entered VFO Post Chilling and as such my measurements are not at ~100 degrees but at 20 degrees or thereabouts. So obviously that's another potential variable (error) in the way I have been doing it due to water expansion / contraction differences. Really I am measuring EOBV-A more so than VFO and by the sounds of it the Temperature expansion is taken into account, so something else I'll need to be aware of. I guess if I took my EOBV-A and multiplied it by the expansion factor at 100 degrees I still should have the same figure. (But I haven't done that to date)

What more got me inquisitive was being I had pellets and when I pulled the sock the pellets obviously retained some moisture as well as the "mush", was how much volume I was actually pulling from the Kettle, although not massive it was still a fair bit of product at around 500mls or so all up from 24 odd litres of wort.

But as you say certainly nothing to get too caught up in. I just like to try and be consistent in doing things the right way as you had intended and not just the way "I think is right!"

Thanks for clearing it up though

• • SVA Brewer With Over 50 Brews From Australia
  • Quote
• • • 0
    • 0
    • 0
    • 0
    • 0

psssss.... Hey bundy, I'll whisper this so PP doesn't hear (Shhh..).

In the link "clear brewing terminology" post#2 refers to the abbreviations. We use VFO & VAW now, not EOBV.

• • SVA Brewer With Over 100 Brews From Great Britain
  • Quote
• • • 0
    • 0
    • 0
    • 0
    • 0

• • SVA Brewer With Over 50 Brews From Australia
  • Quote
• • • 0
    • 0
    • 0
    • 0
    • 0