Hops Utilization experiments with Beer Alchemy

Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Kraftwerk

Supporting Member
HBT Supporter
Joined
Sep 1, 2010
Messages
73
Reaction score
4
Location
Los Gatos
Though I'm a total n00b to brewing (got my first 2 batches fermenting right now), I've been geeking out hard on the topic of hops utilization in extract brewing. I've got a typical stovetop set-up: 3 gallon boils, topping off to 5 in the fermentor. I'm focusing on IPA to start, so the issue of hops is a big one for me. So I got Beer Alchemy and plugged in the Northern Brewer Chinook IPA and Three Hearted IPA recipes as-is, and this is what I got (pay attention to IBU):

Chinook IPA Partial Boil Early Extract addition
http://homepage.mac.com/adsomers/BeerAlchemy_Pages/51AE9C9E-5A31-4787-87ED-31A33DD4D083.html

Three Hearted IPA Partial Boil Early Extract addition
http://homepage.mac.com/adsomers/BeerAlchemy_Pages/83D3DB9E-4D5A-447B-B91C-D446F717F2D8.html

I changed these up to use 1/3 of the extract at start of boil and the rest at the end (I added the rest at 20 minutes to end of boil):

Chinook IPA Partial Boil Late Extract addition
http://homepage.mac.com/adsomers/BeerAlchemy_Pages/961978B5-1696-49E9-A8BD-CDA82314F78F.html

Three Hearted IPA Partial Boil Late Extract addition
http://homepage.mac.com/adsomers/BeerAlchemy_Pages/63041ADE-C244-4DD2-95A1-61BB185999CB.html

Notice:
Chinook Early = 40.4 IBU
Chinook Late = 62.9 IBU
Three Hearted Early = 46.1 IBU
Three Hearted Late = 89.7 IBU

Another thing to consider is that these recipes call for 2.5 gal boils. Plugging that in gives:

Chinook Early = 34 IBU
Chinook Late = 58 IBU
Three Hearted Early = 37 IBU
Three Hearted Late = 82 IBU

Talking about the AIPA style, wouldn't anything less than 40 IBU be under the mark? So At a minimum, it seems doing 3 gal boil is a good start. The late extract technique produces a huge return, according to Beer Alchemy.

But how reliable would you say these outcomes are? In light of some conversation I've heard that extract density in the boil does not affect AA isomerization effeciency, I'm really curious to know if there is any way to accurately calculate IBUs in a partial boil.

For giggles I went ahead and plugged in the Chinook Recipe as a full boil:

Chinook IPA Full Boil Early Extract Addition
http://homepage.mac.com/adsomers/BeerAlchemy_Pages/CA4767F6-0401-4D38-A2B8-3FFFDAA05A6F.html

Chinook IPA Full Boil Late Extract Addition
http://homepage.mac.com/adsomers/BeerAlchemy_Pages/6FA66A03-1108-442E-9D35-ED94B9640CAF.html

The IBU Spread is again about 20
Full Boil Early: 57.3 IBU
Full Boil Late: 77.4 IBU
 
Hey. I also do partial boils and use beer alchemy. How accurately would you say hops utilization is portrayed by the figures shown in your post, given your own experimentation? Which formula do you think is most accurate at predicting utilization in a partial boil (if any?)? I'm planning my first IPA soon and can only boil 2.5 gallons with my current brew pot. I have my hops schedule planned using brew alchemy but am a little worried the utilization won't be as efficient as calculated and I'll end up with 5-gallons of malty treacle
 
Not sure how much this adds to the thread but I happen to be drinking my first fully carb'd three hearted ale from Northern brewer and I did a late extract addition on it. It has an excellent hop bite to it and came out close in color, just slightly darker than bells. I am a big fan of bells two hearted and this is a very close comparison. Not sure I'd call it a direct clone because mine is a little less bitter, but in a side by side taste test I actually prefer it less bitter. it's a great extract kit and something I'll be brewing often.
 
Back
Top