Wort volume vs. IBUs?

[OhReally]

Hey all-

I'm about to start a new batch that is my own little variation on the DuClaw Co.'s offering "Devil's Milk" (with a name like that, how can anyone resist?). The directions I'm using suggest that after steeping the specialty grains, to raise the wort volume to 5.5 gallons for the 120 min. boil. Trouble is, I don't have a 6+ gallon pot (I feel my poor electric stove would start to get cranky at anything bigger than the 5 gal. I've got). I know that wort volume and IBUs are connected, so do you think I can do a, say, 3 or 4 gallon boil without adversely affecting the taste too much?

OG: 1.097
FG: 1.020
IBU: 89
ABV 10.5% (yes, a heavy hitter. It's Satan's choice; what do you expect?)

Thanks, and cheers!
_____________________________________________________
Primary 1: Ex-Pat historic 1800 IPA
Bottled: Pumpkin Spice Porter, India Black Ale, Weizenbier
Drinking: Nefarious Blonde Ale

 

[BigB]

Yes, the difference would be minimal. Plus with IBUs at 89 to begin with, you won't perceive any difference a few points less.

 

[TopherM]

What's your intended final volume?? Just curious, because on my system if I boiled 5.5 gallons for 120 minutes, I'd end up with about a 3.25 gallon yield. Are you topping off at the end?

 

[david_42]

100 IBU is about the limit an open boil can manage, so when you dilute you'll have a lower value. One option is to boil some of the hops ahead of time in the top-off water.

 

[OhReally]

What's your intended final volume?? Just curious, because on my system if I boiled 5.5 gallons for 120 minutes, I'd end up with about a 3.25 gallon yield. Are you topping off at the end?

That's right, I am topping off to get to 5 gal. I boiled this up the other night. Here's the recipe I used:

9 lbs. Light LME
3 lbs. Light DME

.8 lb. Red Wheat
.4 lb. Crystal 60L
.4 lb. Melanoidin
.2 lb. Torrified Wheat

3 oz. Chinook pellets (AA 11.8%)
2 oz. Willamette pellets (AA 4.7%)
1 oz. Columbus pellets (AA 17.5%)

Steep grains in 2.5 gal. water at 150-155 for 25 mins.

Brought to boil and added all extracts, then brought that back to boil (so now, maybe 3 or 3.5 gallons?). Now the long 120 min. boil:

1.5 oz. Chinook, 120 min.

Irish Moss, .70 oz. Willamette, .50 oz. Chinook, .50 oz. Columbus, last 15 min.

.60 oz. Willamette, .60 oz. Chinook, .50 oz. Columbus, last 1.5 min.

By the end of 2 hours, the wort was a really thick and syrupy maroon color, and maybe 2 gallons, which I topped off to 5 with more water. OG reading was 1.090, a little lower than the 1.097 stated in the recipe, but maybe (with luck) the FG will be 1.013 instead of 1.020.

Pitched 2 packets of Safale-05 (about a half packet more than Mr. Malty said). I've got another .50 oz each of the Chinook and Willamette, so I'll dry hop with those when the time comes.

(Sorry for the slight divergence.) I'm not sure what IBUs will result from all this, but I'll have to do some more calculations. Thoughts anyone?

Cheers, y'all!

 

[Calder]

100 IBU is about the limit an open boil can manage, so when you dilute you'll have a lower value. One option is to boil some of the hops ahead of time in the top-off water.

Found you again with the same information. I'm not sure you are correct about the 100 IBU limit for wort. Maybe you are, but I have yet to see any evidence. There is some evidence that fermented beer cannot have much more than 100 IBUs.

Please, if you have some reference,provide it. This is a question I would really like to understand, rather than just accept someone's statement that you can't do it.

 

[BigB]

I have no opinion in this discussion whatsoever...as the science is a bit beyond my desire to contemplate right now. But I did find this interesting thread in the Brew Science section. Might be a place to start for research or continued discussion:

https://www.homebrewtalk.com/f128/maximum-iso-alpha-acid-can-absorbed-during-boil-264781/