Hop Utilisation Percentage

[crackers]

I know the hop utilisation percentages for the folllowing

60min boil = 32%
30min boil = 24%

does anyone know the percentages for the following
45min boil
15min
10min
5min
1min

probably the last two doesnt matter as it would be too hard to taste the difference.


cheers
crackers

 

[Murray]

Palmer has quite a bit of information about hop utilisation.

http://www.howtobrew.com/section1/chapter5-5.html

I've played around with the maths for calculating utilization values, but it is quite a bit more complex than most brewing maths and isn't really necessary.

 

[jayse]

in my experience crackers those numbers your using are too high.
The palmer book which is the same as the tinseth method seems to work much better.
With that method it basically tells you its almost impossible to get 32% utilization in a 60 minute boil its more like 24% for 60 minutes.
It all depends on the gravity but 32% is near impossible.

Anyway the easiest way is just use palmers chart.


Jayse

 

[Jovial_Monk]

Yes it all depends on gravity, the higher the gravity the more the utilisation drops

assuming a gravity (at the end of boil) is no more than 1050 then for pellet hops

1 min-don't be ridiculous%
5 min-6%
10 min-(9% interpolated)
15 min-12%
30 min-22%
45 min-25%
60 min-27%


These figures are out of Randy Mosher's Homebrewers Companion. I use them for my own brewing and for the shop recipes, seem to work OK

I adjusted the recipe for a Russian Imperial Stout from 70g hops to 300g! (Beer is still sitting in cornie till Aug next year, hydrometer sample tasted damn nice!)





Jovial Monk

 

[crackers]

thanks guys
will use the palmers graph. looks easy enuff to interpolate.


cheers & seasons greeetings
crackers

 

[crackers]

another question guys

when i calculate the ibu's im using the final volume (fermented amount).
should i use the final boiled volume (fermented amount + turb amount)

from palmers book i found the formula

ibu's = (grams x AA% ) x Utilization % x 10
--------------------------------------------
volume




is this example correct for a OG of 1.064


ibu's = (20 x 9.8) x .2002 x 10
----------------------------
25


ibu's = 15.7


is this correct.??

cheers & merry xmas
crackers

 

[RobW]

Use the final volume. Palmer's example is a 5 gallon final volume that uses 6 lbs of dry malt extract in 3 gallons of water because of the pot size & the remaining water is added in the fermenter.

 

[crackers]

ken
palmer is adding more to achieve the final volume.
i doing the opposite
if im boiling the full amount and leave a bit behind in the boiler
what volume size should i use
after doing some calcs i think i should use the full amount
but after some clarification.

cheers
crackers

 

[Murray]

You are best off using the fermentation volume, unless you are going quite a bit over your target final volume in your boil. In that case, you would be best off using that volume minus trub volume, which would be difficult to measure.

The most important thing IMHO is picking one method for the calculation and sticking with it.

 

[RobW]

Crackers

I think it should work both ways. The IBUs are a measure of the amount of hop bitterness by volume so if you dilute by addition of water you lower the IBU value & if you reduce the volume by boiling you increase the IBU value. It's the amount of hop bitterness in the final volume of wort that you are after.

 

[crackers]

guys...

i think i'll use the finished boiled volume as value in the equation.
thanks for your help..

now how does the equation look.
is it right as palmer does'nt give a metric version, only subsitute values.

xmas cheers
crackers

 

[Jovial_Monk]

The equation is wrong

IBU = wt * AA * U/(10 * V)

I base my IBUs on the volume left in the kettle after the boil: all the wort in the kettle has the same IBUs regardless of whether it goes into the fermenter or stays trapped in hops etc in the kettle. Of course, I do full wort boils, for smaller boils base it on the fermenter volume

Jovial Monk

Admin edit: Sparse post

 

[crackers]

JM

using your formula the bitterness comes out to 0.15 ??

ibu's = (20 x 9.8) x .2002 / 10*25
= 0.15

surley this isnt correct

palmer say sub 10 for 75 when using metric.

cheers
crackers

 

[Jovial_Monk]

Ah, Ok I see the prob

I express 20% utilisation as 20, then the 10 goes on the bottom, that is the difference, sorry I didn't notice the .2002

JM

Admin edit: Sparse post

 

[crackers]

okay.
sorry i just used palmers graph.

so the formlua is correct..
bring on the holidays..
gonna be brewing as oftten as i can.


cheers merry xmas
crackers

 

[Jovial_Monk]

yeah baby, brewing. . .

have a dopplebock/bock brewday lined up meself
low temp dough in, let betaglucanase reduce the gummy betaglucans in the TONS of dark Munich I will be using, some additional infusion around acid rest point, to protein rest, pull decoction, mash overnight

only one brewday but it will be long and challenging
recipe I was given, had 500g cararoma

stuff caramalts
more dark munich instead, much more. . .
and a long boil, 3 or 4 hours, to darken the wort

i will be in a sticky worty heaven some tim e soonish after Christmass. . .

Any Adelaideans want to watch/assist with a full mash?




Jovial Monk