Homebrewers Association | AHA Forum

General Category => Ingredients => Topic started by: nateo on August 09, 2012, 06:40:40 AM

Title: Low-temp hop utilization - FWH w/o boil?
Post by: nateo on August 09, 2012, 06:40:40 AM
I've been looking around but haven't found info about hop utilization by temperature. I'm wondering if I can use FWH with a no-boil Berliner Weisse, and if so, how I'd figure what kind of bitterness I'd get from it.
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: tygo on August 09, 2012, 08:12:50 AM
I don't have an actual answer for you, but my guess is that you'll get some flavor and aroma from the hops but not much bitterness at all.  I don't have a specific source to point to (I only googled around for a couple of minutes) but the gist seems to be that not much isomerization, if any, is going to occur at mash temperatures
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: mihalybaci on August 09, 2012, 08:27:18 AM
The "Building Your IPA Hop Recipe" from the July/August 2012 issue of Zymgury says that isomerization occurs above 185F, so I imagine you wouldn't add any bitterness (or at least not very much) if you stay below that temp. The article says "time and temp dependent", but doesn't really specify the difference between 60 min at 212F or 60 min at 200F. Not sure if that helps, but maybe its a starting point?
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: denny on August 09, 2012, 08:31:52 AM
Stan Heironymous is writing a book about hops.  I don't know that he dug up any info on usage for it, but he might have.  You might try contacting him.
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: krazykrausen on August 09, 2012, 09:22:32 PM
Hops taste bitter, whether they are isomerized or not. Eat a pellet and you'll know. So you may not add any IBU's doing FWH with no boil, but if you add hops you are adding bitterness

You won't need much for a Berliner anyway. Just off the top of my head, I'd add 1oz of a Magnum (or something neutral) to the FWH, should be good

-Ton
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: Kaiser on August 10, 2012, 05:01:23 AM
You need isomerization to get bitterness that stays in the beer. unisomerized alpha acids don't dissolve well and the few that do will come out when the PH drops during fermentation.

Kai
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: krazykrausen on August 10, 2012, 08:51:00 AM
So if I add something that tastes bitter to a solution, that solution will not taste bitter? I'm not sure I understand how that can happen. A hop pellet does not isomerize in my mouth, but it tastes very bitter

*not trying to by sarcastic, I'm just not sure understand the science at play here*

-Ton
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: nateo on August 10, 2012, 09:05:50 AM
If I follow Kai, isomerized hop acids are more stable in solution, while unisomerized acids will drop out of solution over time. So it might be bitter at first, but bitterness should decrease with storage time?
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: Kaiser on August 10, 2012, 09:48:31 AM
Here is a chart from Brigg's book that might be useful: (http://braukaiser.com/wiki/index.php?title=How_pH_affects_brewing#Hop_utilization)

(http://braukaiser.com/wiki/images/3/36/Alpha_acid_solubility.gif)

pH drop will precipitate more unisomerized hop acids. There might be some bitterness you get from unizomerized acids still present in the wort. But its difficult to say if bitterness in a not boiled but heated wort is from isomerized or unizomerized acids.

Does it really matter? I think you'll have to experiment.

Kai
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: krazykrausen on August 10, 2012, 10:19:30 AM
Very helpful, thanks guys!

-Ton
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: DrewG on August 10, 2012, 12:00:41 PM
Could you use hop extract? Pretty sure Northern Brewer carries it.
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: erockrph on August 10, 2012, 12:12:27 PM
Could you use hop extract? Pretty sure Northern Brewer carries it.

NB carries Hop Shot, which is just a CO2-extracted hop extract. It needs to be boiled, just like hops. Think of it like hops in liquid form.

You are thinking of iso-AA extract. I'm not sure if there is a retailer that has this available to homebrewers.
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: hoser on August 10, 2012, 12:21:54 PM
Morebeer carries Isohop extract, rather pricey....

http://morebeer.com/view_product/7835//IsoHop_Bitterness_Extract_1_oz
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: Kaiser on August 10, 2012, 12:56:48 PM
Morebeer carries Isohop extract, rather pricey....

http://morebeer.com/view_product/7835//IsoHop_Bitterness_Extract_1_oz

Combine that with the fact:

Quote
... ISOHOP will stay fresh for approximately 2-3 months from the time it is opened ...

Not all that practical for home brewers.

Kai
Title: Re: Low-temp hop utilization - FWH w/o boil?
Post by: tschmidlin on August 13, 2012, 12:38:59 AM
So if I add something that tastes bitter to a solution, that solution will not taste bitter? I'm not sure I understand how that can happen. A hop pellet does not isomerize in my mouth, but it tastes very bitter

*not trying to by sarcastic, I'm just not sure understand the science at play here*

-Ton
For it to taste bitter, the bitter compounds just need to come into contact with the bitter receptors on your tongue.  The molecules are present in a hop pellet, that's why it tastes bitter.  If they don't linger in the beer because they're not isomerized, then it won't taste bitter.