Testing Alpha acids

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Warrior

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This has probably been covered here before but I was wondering if there is an inexpensive way to have your homegrown hops alpha acid tested?
 
I think I remember reading something about this a while back. I think you can send a lab a sample along with $40 to have them test your hops. That's not all that bad, but I would wait until your plants are well established.
 
Not sure, but I'm guessing no since most people don't get it done... Not sure I've ever read of anyone getting it done and I read a lot here. I'm sure SOMEONE can do it, but for a price...

I guess this is why people will bitter with normal pellets or flowers from the LHBS (that do have an AA%) and use their homegrown stuff primarily for flavor and aroma. The IBU difference created from 15-20 minute or less additions is not near as critical, so it doesn't matter if your homegrown cascade are the normal 5% you may buy at the LHBS or if they are 2-3%...
 
Mail them to me, and I can do it. Seriously, it's quite easy if you have access to the instruments and the mad geek skillz.

EDIT: I double-checked some Willamette leafs I got from the LHBS listed at 4.7%...I calculated them to be 3.1% after 2 years. Not bad. I also double-checked some 2007 Targets at 11.7% and I determined them to be 11.64%.
 
mrkristofo said:
Mail them to me, and I can do it. Seriously, it's quite easy if you have access to the instruments.

You should start making a buck (notice I said a buck, not hundreds of them! :) ) off HBT'ers who want to have their hops tested! Sweet deal...
 
mrkristofo said:
Mail them to me, and I can do it. Seriously, it's quite easy if you have access to the instruments.

You realize you just opened up a pandora's box, right? The line starts with Warrior, then me... take a number...
 
mrkristofo said:
Mail them to me, and I can do it. Seriously, it's quite easy if you have access to the instruments and the mad geek skillz.
Can you elaborate on the process? I'm not suggesting that I'm going to start up a hop measuring business or service (I'm fairly certain I don't have access to the lab equipment required). I'm just curious about how it's done.
 
Yuri_Rage said:
Can you elaborate on the process? I'm not suggesting that I'm going to start up a hop measuring business or service (I'm fairly certain I don't have access to the lab equipment required). I'm just curious about how it's done.

+1, curious as well...
 
RoaringBrewer said:
You should start making a buck (notice I said a buck, not hundreds of them! :) ) off HBT'ers who want to have their hops tested! Sweet deal...

I don't want to make any cash off of it, because the instruments in the lab are provided by federally funded grants. Making money off of it is probably illegal on a few different levels. But I can geek out and scan whatever I want. So I'll just take payment in a different form of green...keeping the extra hops I don't need for the extraction.
 
mrkristofo said:
I don't want to make any cash off of it, because the instruments in the lab are provided by federally funded grants. Making money off of it is probably illegal on a few different levels. But I can geek out and scan whatever I want. So I'll just take payment in a different form of green...keeping the extra hops I don't need for the extraction.

Sounds like a plan... I'm so in the dark as to the process, I thought maybe you could do it from home somehow, haha.
 
Yuri_Rage said:
Can you elaborate on the process? I'm not suggesting that I'm going to start up a hop measuring business or service (I'm fairly certain I don't have access to the lab equipment required). I'm just curious about how it's done.

There's a paper on it in the JASBC if you want the real nitty-gritty, but basically it's a UV absorbance spectra after an organic extraction of the alpha and beta acids from a specific mass of hops. Determine the concentration of alpha and beta, then extrapolate those numbers out to a mass/mass ratio with the hop matter.

That will give you a %alpha and %beta numbers.

You can determine % humulone/cohumulone/isohumulone using HPLC.
 
mrkristofo said:
Mail them to me, and I can do it. Seriously, it's quite easy if you have access to the instruments and the mad geek skillz.

EDIT: I double-checked some Willamette leafs I got from the LHBS listed at 4.7%...I calculated them to be 3.1% after 2 years. Not bad. I also double-checked some 2007 Targets at 11.7% and I determined them to be 11.64%.

IIRC, Gas Chromatograph right? Or is it HPLC?

Do the resins have to be solubalized in something to test?

I have been looking into the procedure but haven't come up with much of anything (not that I have access to any equipment). I've even combed the USDA R&D site and read a lot about results but not the process.

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Basic brewing did a podcast in 2007, I think. Too lazy to look up the link. IIRC, in the podcast they gave a contact name for an individual at the USDA testing labs. They said for $45 per ounce the USDA could do a full spectrum analysis.

As for me, I'll use the base potential from the known range for the variety. Brew a batch, take good notes, and adjust up or down from there. Just like I'd do with any other unfamiliar variety. The numbers are just guidelines anyway.
 
mrkristofo said:
There's a paper on it in the JASBC if you want the real nitty-gritty, but basically it's a UV absorbance spectra after an organic extraction of the alpha and beta acids from a specific mass of hops. Determine the concentration of alpha and beta, then extrapolate those numbers out to a mass/mass ratio with the hop matter.

That will give you a %alpha and %beta numbers.

You can determine % humulone/cohumulone/isohumulone using HPLC.

Could you provide the link? I went to the ASBC and searched hops. It resulted in 10 pages of journal publications. I like to read the Nitty Gritty, even if I don't actually abide by it.
 
mrkristofo said:
I don't want to make any cash off of it, because the instruments in the lab are provided by federally funded grants. Making money off of it is probably illegal on a few different levels. But I can geek out and scan whatever I want. So I'll just take payment in a different form of green...keeping the extra hops I don't need for the extraction.
Great Idea! Come harvest season I know several growers who definately wouldn't mind parting with some of their hops for an Alpha acid reading in return.
 
GilaMinumBeer said:
Could you provide the link? I went to the ASBC and searched hops. It resulted in 10 pages of journal publications. I like to read the Nitty Gritty, even if I don't actually abide by it.

You can find the details in ALDERTON, G., BAILEY, G. F., LEWIS, J. C. and STITT, F. (1954) Analyt. Chem., 26, 983.

And in the CRC guide to Brewing Science and Practice, section 8.2.3 - Analysis of the hop resins, pp. 268-269.
 
Does anyone know what determines the AA in the hops? Is it age of plant, water and soil, or what?

I am hoping it is growing environment since I am in the Willamette Valley I am just going to assume whatever they hops are listed at for the year that is probably what I will have as well.
 
Mail them to me, and I can do it. Seriously, it's quite easy if you have access to the instruments and the mad geek skillz.

EDIT: I double-checked some Willamette leafs I got from the LHBS listed at 4.7%...I calculated them to be 3.1% after 2 years. Not bad. I also double-checked some 2007 Targets at 11.7% and I determined them to be 11.64%.
I have some Cascade and Nugget, could you test these for me?
 
I have access to a nanodrop :) Should be able to do the extraction and analysis fairly easily! If it goes well, I might be tempted to do the analysis for fellow HBTers :)
 
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