hops adjustment

[StallionMang]

Hi all.

I started using BeerSmith to calculate IBU values, and I have been tweaking the hop additions to a particular recipe because I would be doing a partial boil (2.5 gal) instead of a full boil. The particular recipe I am looking at has an initial hop addition of 1.5 oz (assuming full boil).

Now for the partial boil, I have 2 choices, and I am trying to decide which would be best.

Approach A: Double the initial bittering hops addition to 3.0 oz, but leave all of the other additions the same.

Approach B: Increase all of the additions (bittering, flavoring, and aroma) by a more moderate amount in order to achieve the same IBU as Approach A.

Now, to determine which of these approaches would be best, I need to know how an increase in the boil gravity affects hop utilization. Does it only affect the bittering aspect of hops utilization? If so, then Approach A would be best. Or does it decrease utilization in all aspects (bittering, flavoring, and aroma)? If so, then Approach B would be best.

Any guidance you all can offer would be greatly appreciated.

Thanks,

Robert

 

[Poindexter]

46 reads and nobody wants to guess. I don't want to guess either.

One thing you can do is up the 60 minute hops _and_ start with only part of your extract in the pot.

Even better would be two boils of 60 minutes each.

Your software isn't guessing because there are too many variables. But you do already have BeerSmith. How long before you step up from 2.5g boils to a bigger kettle?

Personally converting an 5gAG recipe back to 2.5gextract I would probably step up the 60 and 30 minute hops by 40-50%...but I would only have about a third of the extract in the brew kettle.

With 20 minutes left in the boil I would add the rest of the extract, and then as soon as I got hot break I would spoon some wort out and get it cooled so I could taste it in time to make a educated guess about 15 minute hops. Same for steeping.

And then I would dry hop on 2° ferment, leisurely and heavily. But I know I like the nose and front side of hops more than the finish, I want just enough 60 and 30 minute hops to make me finish happy (hoppy?), you may not like that.

The only good answer is Relax, Don't Worry, Have a Home Brew. You are going to need 'more,' and that is really all anyone can say.

So: RDWHAHB!

 

[StallionMang]

Thanks, Poindexter!

Actually, I was able to determine that the flavor and aroma additions would not be affected by the boil gravity. Therefore, I will plan on simply adjusting the bittering hops, which was Approach A in my initial posting.

Thanks again!

Robert

 

[homebrewer_99]

I may be wrong, but from what I read I think your thinking is wrong.

You would need to double up on your hops only if you were reducing your boil time in half.

I do 1.5 gal boils. In Charlie P's TCJOHB there's a chart that basically lays out that boiling 1 gal of water with 1 lb of malt and 1 oz of hops boiled for 1 hour gives you a gravity of 1.040 and the maximum bitterness extraction of 30%. What's interesting is a 90 min boil does not extract any more bitterness than a 60 min boil. The only reason people still do 90+ min boils is to reduce their water volume.

I use 1.5 gals because when I'm done boiling for 60 mins I have about 1 gal left.

With my Hefe Weizens I only use 3% AA and they are damn near perfect.

I usually boil for 45 mins then remove the pot from the heat and add in all the rest of the malts then steep them for the last 15 mins. Pour it into the primary and top off with PUR filtered tap water...done.

 

[StallionMang]

homebrewer_99: I appreciate your reply. The reason why I was planning on doubling up on the inital addition of the bittering hops is because the orginal amount listed in the recipe was suited for a 5 gallon boil, and cutting that in half to a 2.5 gallon boil increases the wort gravity significantly, which has a big impact on hop utilization.

This reasoning is not just based on my intuition. It is also based on the numbers that the BeerSmith software gave me when I tested the recipe using both a 5 gallon and 2.5 gallon boil. The numbers were perfectly in line with what I calcuated myself using the AAUxUx75/Vrecipe equation in conjunction with the Tinseth chart. http://www.howtobrew.com/section1/chapter5-5.html

 

[StallionMang]

Oh yeah...one other thing. Perhaps I didn't communicate that this plan of mine involved adding all of the extract at the outset.

FYI, I am no longer planning on doing the doubling up of the bittering hops. Instead, I am planning on adding only 3 lbs of DME at the beginning, and then adding the remaining 4 lbs with only 5 minutes left in the boil. This will help decrease the wort gravity so that I don't need to add more hops.

Thanks!

Robert

 

[homebrewer_99]

What's the recipe/style?

 

[Poindexter]

I can't find the link now, DUH, but there is a huge thread here, pages and pages, about adding *ME late in the boil and so on.

perhaps homebrewer_99 can link you into it, I started messing with it because of him in that thread.

 

[StallionMang]

It was Jaded Dog's All-Amarillo recipe. https://www.homebrewtalk.com/showthread.php?t=42747

For BeerSmith, I entered an estimated OG of 1.064. I derived that by assuming that the steeped Crystal 40 is approx. 22 gravity points-per-pound-per-gallon (ppg) and the Muntons Extra Light is approx. 44 ppg.

As you can see from the thread, Jaded Dog and I went back-and-forth, and now I think the reason that we weren't on the same page is that Jaded Dog does late addition of DME, which makes a big difference. When I decided to add 4 of the 7 lbs at the end of the boil, I did some re-calculations, and Jaded Dog's original numbers in the recipe ended up being very close to mine. I got an IBU of around 50.

BTW, my amariilo hops are pellets and are 7% AA instead of the 8% in Jaded Dog's recipe.

 

[StallionMang]

Poindexter:

I found that thread. That's where I got the idea to do late DME addition

I also made a comment to that thread.

Thanks!

 

[homebrewer_99]

Sounds lke you found it OK and all's well with the IBUs.