Wort Bitternes

[sjc]

Here's a query to ponder over you afternoon/evening beer.

I made 21 L of wort on Sunday with an OG of 1.058 which I intended to bitter to 30 IBU but due to an error in my spreadsheet, was only bittered to 21 IBU. I have saved 2 L of wort from the day (filtered from the trub and hobs and vacuum sterilised in mason jars using a trusty old Namco pressure cooker), so potentially I could add extra hops to this saved wort, boil for a while and then add to the fermenting wort to achieve the desired 30 IBU. So the question is how do I calculate how much hops to add and how long to boil in these two litres of wort such that when added to the other 21 L I achieve the extra 9 IBUs?

Regards
Stephen. :unsure:

 

[Airgead]

Here's a query to ponder over you afternoon/evening beer.

I made 21 L of wort on Sunday with an OG of 1.058 which I intended to bitter to 30 IBU but due to an error in my spreadsheet, was only bittered to 21 IBU. I have saved 2 L of wort from the day (filtered from the trub and hobs and vacuum sterilised in mason jars using a trusty old Namco pressure cooker), so potentially I could add extra hops to this saved wort, boil for a while and then add to the fermenting wort to achieve the desired 30 IBU. So the question is how do I calculate how much hops to add and how long to boil in these two litres of wort such that when added to the other 21 L I achieve the extra 9 IBUs?

Regards
Stephen. :unsure:

[post="128540"][/post]​

Stephen

Well if my maths is correct -

2l is about 10% of 21l (close enough anyway) so adding 2l at X IBUs will alter the IBU of the final volume by X/10 where X > 21 (as adding < 21 IBUs will actually reduce the overall IBUS). I hope that made sense.

So to add 9 IBUs to 21l you would need 10*9 or 90 IBUs in your 2l. thats a heck of a lot of hops to add to 2l of wort. i'm not sure that's going to work...

Captain... she canae take any more...

Much as I hate to suggest it - hop extract perhaps? Or just drink that batch up as is and brew another.

Cheers
Dave

 

[Ross]

Steve,

Brew another one at 40 IBU & blend the 2 - You can't have too much beer Steve :chug:


cheers Ross

 

[sjc]

Ross and Airgead
thanks for the suggestions. I'll probably just be satisfied with the IBUs as they are. Your suggestion isn't bad Ross, but you know I don't have kegs and the idea of bottling 60 L in one session doesn't thrill me. :excl:
Cheers
Stephen.

 

[Ross]

Ross and Airgead
thanks for the suggestions. I'll probably just be satisfied with the IBUs as they are. Your suggestion isn't bad Ross, but you know I don't have kegs and the idea of bottling 60 L in one session doesn't thrill me. :excl:
Cheers
Stephen.

[post="128562"][/post]​

I know someone with a keg who'll help you out

cheers Ross