Ibu

[Ster]

IBU is a function of AAUs and starting gravity. However, when using a partial boil, you must adjust by the boil volume to compute the boil gravity.

So here is my question:

Wouldn't adding malts @ flameout actually mean that much less malts were boiled with the bittering hops, therfore the actual boil gravity is MUCH lower than most equations predict (ie Palmer)? And this will greatly influence hop utilization???

 

[frazier]

In a word, yes. Use the boil gravity, not the recipe's OG, in the calculator.

 

[Mozart]

In a word, yes. Use the boil gravity, not the recipe's OG, in the calculator.

^This.

Also, most calculators I've encountered have separate inputs for boil volume and final volume for just this purpose.

 

[Ster]

Yes mine has boil volume vs total volume, but no option for how much malts were actually boiled with the hops.

It asks for target OG, but like I said, If I add malts @ flameout, my target OG has no correlation to my boil gravity. I could boil all the malts or just a fraction.

I use brewers friend android app.

 

[boydster]

Do yourself a favor and get some software for your computer. BeerSmith, Brewtarget... Those both allow you to include the malt (or any fermentables) as a late addition, and if you do that it will remove those gravity points from the calculated boil gravity.

 

[cheezydemon3]

AWESOME noob question!!!!!!!!!!

I always add a decent bit of DME at start of boil, even if the bulk is at flameout (or 10 minutes for me)

 

[uncleleon]

IBUs and my brewing software are starting to make me think I'm loosing it.
This recipe (from aha) listed 20 IBUs. my software says 70ish and it always seems wrong to my taste buds. I can't get a handle on this. Someone point me to a good thread.

 

[Ster]

Shoot me your email and I can send you an excel spreadsheet that I created from Palmers equations. (Assuming you are brewing with extract and specialty grains)

 

[speeddemon190]

The web based brewersfriend site from the computer has an arrow underneath your fermentables which allows you to make them late additions. the button has an arrow pointing down that says all. then gives you the choice right underneath each fermentable to check it as a late addition.

 

[boydster]

You can do late addition on brewtarget, go to the fermentables tab and check the box that says "Normal". It should change to "Late"