Pre Boil Volume

[Margwar]

Hey there all...

I was just wondering those who use a 50L keggle what volume of wort do you start with for a 60min boil?
Just need a figure to work off as I think I am stuffing my pre boil volumes up a bit...

Thanks,

Dietz

 

[manticle]

I go for a round 30-32. Lose approx 9-10 litres but my boils are 75 minutes mostly.

 

[Margwar]

I go for a round 30-32. Lose approx 9-10 litres but my boils are 75 minutes mostly.

How come you do 75min?
I normaly do 60 for a Ale and 90 for a lager...

 

[manticle]

Once it hits the boil, I boil for 15 minutes before the first hop addition. My understanding is that it helps drive away precursors and compounds like SMM (presursor to DMS) and that hops are better added once the hot break has been given a good chance to break up and drop back into the wort.

 

[argon]

Hey there all...

I was just wondering those who use a 50L keggle what volume of wort do you start with for a 60min boil?
Just need a figure to work off as I think I am stuffing my pre boil volumes up a bit...

Thanks,

Dietz

Obviously it greatly depends on your batch size and a few other factors including the shape of your kettle. My keggle is tall and thin. So i probably lose less during the boil due to surface evaporation.

So... let's assume a 23L batch. I have set up in Beersmith with the following figures for 23L batch
Evap rate 9% = 2.67L
Loss to trub and chiller 3L
Cooling loss pct 4% = 0.96L
Boil time 60mins
Final Volume 23L
This give me a 60min Boil Volume of 29.62L

(90min Boil Volume = 31.17L)

So aim for around 30L for a 23L batch / 60 min boil and around 31L for a 90min boil. :icon_cheers:

 

[Scruffy]

Yes indeed for the short interlude before the first Hop, for all the same reasons.

I usually start with a little over 40l in the 60l pot, after a 90m boil and taking losses to trub, water absorbed by 8KG+ of grain (as I BIAB in that pot), etc, etc, into account I'm left with just under 20l - seems to have worked out like that for the last 26 brews... Evaporation rates for me are around 14%... quite high.

So for 30l in a 50l pot, at my evaporation rates you will evaporate about 4.2l, and a further 1l to cooling shrinkage. Your starting gravity of 1.050 will finish at 1.060ish. Add trub at kind of 2l you're left with 22/23l,

What figures are you getting?

 

[Scruffy]

apologies for the echo...

 

[scrumpy]

I've got a massive evap rat (about 23%), I start with 34 -36L and end up with 23 in the ferm, thats also allowing for loss to trub. I also boil for 75 min!

 

[argon]

I've got a massive evap rat (about 23%), I start with 34 -36L and end up with 23 in the ferm, thats also allowing for loss to trub. I also boil for 75 min!

whoah that's huge!! Maybe try backing down the burner a touch. Last batch I did I added to Mitch sparge water and tried boiling off the extra... Took and other hour to get to volume, it was like Vesuvius in there... Even had a couple of boil overs. But pretty much didi a 2 hr boil and only lost 6-7L + trub etc

 

[Margwar]

Yes indeed for the short interlude before the first Hop, for all the same reasons.

I usually start with a little over 40l in the 60l pot, after a 90m boil and taking losses to trub, water absorbed by 8KG+ of grain (as I BIAB in that pot), etc, etc, into account I'm left with just under 20l - seems to have worked out like that for the last 26 brews... Evaporation rates for me are around 14%... quite high.

So for 30l in a 50l pot, at my evaporation rates you will evaporate about 4.2l, and a further 1l to cooling shrinkage. Your starting gravity of 1.050 will finish at 1.060ish. Add trub at kind of 2l you're left with 22/23l,

What figures are you getting?

I do not have an accurate measure of my Keggle yet. Need to mark my stirrer this weekend during my brew day.
I did a 60min boil the other week and I reckon I had around 30l in the Keggle. Ended up pretty much filling my cube, only had to push out a little air. Got 21L into my fermenter. Then I did a pilsner next and I added more wort to the keggle and did a 90 min boil. But I only ended up getting around 18L into my fermeneter. I thought I had compensated with the extra wort in the keggle but ended up short.
Think I need to get a sight glass made or mark my stirrer....

 

[Screwtop]

Hey there all...

I was just wondering those who use a 50L keggle what volume of wort do you start with for a 60min boil?
Just need a figure to work off as I think I am stuffing my pre boil volumes up a bit...

Thanks,

Dietz

Depends on what final volume I am shooting for. Should have requested boiloff volume! I normally loose 7+ litres over a 90 min boil, so around 5L per hr.

Screwy

 

[rude]

9 litres loss for me 34 litres to get 25 litres comfortably 90 min boils

 

[brocky_555]

does it make any difference if you have a lid for your kettle ?

 

[Screwtop]

does it make any difference if you have a lid for your kettle ?

Yes, but not if you don't use it.

 

[felon]

I start with 27l for a 70 min boil. This leaves 23.5l at the end of boil and i get 20l into my fermentor.

 

[manticle]

does it make any difference if you have a lid for your kettle ?

Best to have the lid off while you are boiling.

 

[Crusty]

9 litres loss for me 34 litres to get 25 litres comfortably 90 min boils

Pretty much the same for me.
34l boil & end up with 25l into fermenter. I loose about 8l hour, 60min boil but I have the mongolian almost full throttle.
I could definately back the boil off a bit & loose a bit less to evaporation but have everything setup pretty spot on using Beer Tools Pro.

 

[beerbog]

32 litre boil to leave me 27 litres, 21 - 22 into the fermentor, so only a 5l loss to evaporation. :beerbang:

 

[Carboy]

I use a 50lt keg kettle, and this morning I started with 30 litres pre boil, boiled for 70 minutes, got exactly 23 litres in the fermenter.

For a 90 minute boil I strat with 34 litres to get 23 litres.

Cheers
Carboy :icon_cheers: