Let’s guess actual IBUs in a theoretical ‘zero IBU’ DIPA!

Ever wonder what the actual IBUs are in beers that have no hops added in the boil? I have! I’ve homebrewed many beers like this and was always surprised by their clear bitterness, despite their mathematically low IBUs.

One of the perks of pro brewing is the ability to test out hypotheses. So recently we brewed up one of these beers and sent it to the lab. I should be getting the results back by Wednesday, but in the meantime, I thought I’d open a poll and see how close we get!

Now, the clever among you may be thinking, “Silly, Johnnychicago! Adding hops to near-boiling wort is still going to impart bitterness. True! Which is why I made sure to get the wort a little cooler before it saw its first hops. I’ve always seen 175°(79°c) as a rough isomerization cutoff, so I wanted to get well below that. Here’s the details:

Final volume: 11.7 bbl
OG: 17.5° TG: 2.7°
Whirlpool hops: 11 lbs. Amarillo (8.5%AA), 11 lbs. Centennial (8.2%AA)
Dry Hop #1: 11 lbs. each of Amarillo and Centennial at 68° for 4 days.
Dry Hop #2: 22 lbs Mosaic at 55° for 4 days.

Whirlpool hops were added at 165° and between the whirlpool and cool-in, probably saw about 35 min. exposure time.

Beer tastes like a nice, clean, west coast IPA. Definitely huge aromatics, but plenty of perceived bitterness too.

For what it’s worth, I have always personally been of the opinion that IBUs are maybe the most worthless brewing parameter out there...

Give it a guess, feel free to ask me questions, and discuss away!

 

Honestly don’t remember the Mosaic AA, but I can look it up. It wasn’t anything out of the ordinary fwiw.

If I remember correctly, dry hopping raises pH.

Here’s the beer if you are interested: https://untappd.com/b/revolution-brewing-company-louie-louie/2587239

Would have been my blind guess if someone had just handed me a sample without telling me the backstory.

 

I have not! Got a link?

 

5 minute WP, 20 minute rest, about 10-15 minutes to run the beer through the heat ex and drop to fermentation temp.

Also, is there another contributor to IBU other than isomerized AA? Honestly don’t know...

 

Very interesting. We do have an HPLC, I’ll try to get the lab guys to fire it up. I will say that I don’t get any of that off-flavor he describes in the blog. The beer definitaly tastes like a good IPA should.