Poll: Does Your Efficiency Drop During The Boil?

[Gulf Brewery]

Hold on Pedro. I'll just go and get it out of the bin and have a look

Whoops! Need my glasses as well...

And the 4% expand /shrink factor correctly applied should get the missing % you are looking for.

Pedro

 

[Darren]

PP,
the rest of it is above the final volume line as dried sugar clinging to the pot and 200ml/ hydrometer sample has/may have been discarded 8).

I suspect if you take into account the residual left in the WET break material and the concave edges of your pots then you may have got more out from your final gravity than your pre-boil measurement. That is something certainly worth testing.

I guess its a bit like global warming. If you look into it over an acute period of time then there is alway going to be what you look for.

Big waves, big winds probably have always happened over the millenia, but communicating your observation(s) have changed now due to the electronic world.

Global warming, sugar fairies, BLAH BLAH.

After all, the universe is just a spec of dust under a giants fingernail.

Anyhow, seemed like a good thread to spit it out!

cheers

Darren

 

[SJW]

Wow, I'm sure I dont understand but the way I see it, the efficiency is the efficiency! pre boil , post boil and in the fermenter. I calculate my recipes on Beersmith at 75% and if all goes to plan I am at 75% efficiency for my pre boil gravity and the after the boil the gravity would rise to be the 75% value calculated for final gravity. And that reading is the same when I dump into the fermenter. So I canot see how efficiency can change at any stage after the mash.
But its getting late and I have not read the other thread you mentioned.
Sorry I was not much help?

Steve

 

[Fingerlickin_B]

I boil off close enough to 10 litres in a 60 minute boil.

Sorry to take this waaaaay O/T Pat, but is that a normal loss? :huh:

I only lose about 3L give or take...that said, I use an element as opposed to a burner, which may very well make a difference...maybe :unsure:

PZ.

 

[Fingerlickin_B]

Oh, and on-topic...you don't top up your kettle pre-boil/during the boil do you Pat? h34r:

PZ.

 

[PistolPatch]

Whoops! My computer is playing up. Just lost what I wrote here but after a night out on 8.3% beers, I'm pretty sure nothing of value went astray Will answer your questions later Finger etc. when I manage to fix this machine. Nearly time for a re-install I think. Grrr...

 

[Aaron]

Sounds pretty accurate. I take plenty of measurements and write plenty of notes. I understand what is happening during my brew day. However, I have to say the only efficiency figure I care about, and only because I need something to base the calculations for my recipes on, is the brew house efficiency. Right or wrong that is how I work.

I say good on you for doing the experiments but not every experiment is going to be of interest to every brewer.

 

[mobrien]

PP - just for you!

Doing a mid strength amber ale today 46L boil, 41L batch size

into the boiler - expected SG was 1.027 (based on 75% in beersmith), actual was 1.025, 46L

45min into the boil, SG was 1.029, 41L

End of boil (60 mins) SG was 1.030, 39.5 L

After cooling and topping up, SG to fermenter was 1.029, 41L. Predicted was 1.031, 41L

I was down .002 from start to finish.

I'll do the same measurments with my next normal grav batch.

Hope this helps,

Matt

 

[PistolPatch]

Pedro: Thanks again mate. From what I've read, multiplying the volume for boiling wort by 0.96 seems to be right so I don't think I'll find any improvements there. The volumes at beginning and end between ambient and boiled liquor/wort matched pretty closely so I'd say all that is OK.

Finger: I boil in a Robinox 70lt pot that has a 45cm diameter so boil-off is prettty huge. I only do a 60 minute boil now because of this. And I do no top-ups.

Mobrien: Thanks for the figures Matt. Yours come up really nicely. Pretty much a perfect match pre and post-boil for you. Interesting to see the difference in evaporation rates between us too.

One thing that has been interesting in this and the other thread is the wide range of answers in the polls but I've probably mentioned this already

Thanks again to everyone,
Pat

 

[Chad]

I'm hitting all my marks (OG, pre and post boil volumes) fairly consistently now, except for my pre-boil gravity.
My efficiency into the fermenter is 79-80%, but into the boiler is only 66-70%.

I'm at work on my first day back after a short holiday so the head is a little over loaded with work at the moment and don't have time to think this through logically.