Alpha Acid Content

We just harvested this years crop of hops :rockin:

We have fuggle, hallertau and cascade.

is there any way for me to figure out the alpha acid content of these little guys?

The only real way to get AA% is to take beer you made to a lab and have it tested, I believe.
Brew two 1 gallon batches of pale ale, something clean. Use .25oz of your Hallertau in one, and .25oz of Hallertau you got from the store in the other batch. Ferment with the same yeast, at the same temp, for equal period of time. When the beer's done taste the two and compare relative bitterness. Use your best judgment to determine whether your hops are more, less or equally bitter. This should give you a decent reference point.
You could just use the home grown hops for flavor and aroma; at least they won't affect bitterness too much. This way you will get to know the flavor and aroma your hops will impart, then you can use them in other beers when you know what to expect.

True, a lab would be the only real way to prove out what the AAs are, but...why don't you chomp on a known AA and eat one of your own about 10 mins later to see which one tastes more bitter?

I did this to one of my Hallertaus yesterday. I gaged it against a 3.4%. Mine was "lighter" so I deduced so is the AA%.

At any rate you can can use them for aroma hops without any problems.

I think eating raw hops might give you some impression of their total potential bitterness, but it won't translate directly into their bitterness in your beer. Hops contain many compounds that are not believed to provide any flavor to beer. The alpha acids that do contribute flavor must be isomerized before they become soluble, making them more bitter in the process. If the two hops tasted do not have exactly the same ratios of the various alpha acids, they may not isomerize at the same rate and the difference between their flavors in beer may be changed dramatically.

Just the other night I came across this passage in The Homebrewer's Companion:

Bitterness and hop flavor are relative. When discussing hop bitterness and flavor we must always bear in mind that we are referring to bitterness and flavor in beer. While this may be a trivial point, many a brewer has gone temporarily astray by making comparisons of hop bitterness and flavor in other aqueous solutions, such as teas, hot, cold, or otherwise. Assessments of hop teas, though of limited instructional value, cannot, should not and must not be seriously correlated to predictive characters in beer. It just ain't the same.

Click to expand...

Tasting them fresh or dried will give you an idea of their flavor, and with experience I'm sure you can tell a lot about the properties of hops based on taste, but nothing will beat using them in a batch of beer.

Not to be argumentative or anything...

Since none of these are typical bittering hops, AA content isn't much of a consideration. Flavor and aroma oils don't vary as much year to year.

That said, only a lab can determine AA content.

hmm...so you're saying i need a lab...

i think a little trial and error is how i'll do this. fine-tune a recipe and only use the homegrown hops...then adjust as needed. I'll start with a hefeweizen

will the alpha acid vary year to year, when it was harvested, etc? or can i expect pretty much the same result next year?

Yes, AA varies a great deal each year depending on temperatures, sunshine and rain/water. Last year, it was extremely hot out here (20F above the average high), this stresses the plants, as there are limits to how much water they can absorb and move to the leaves. Less energy is available for building the hops.

However, each hop varies within a range (whether homegrown or commercial) ) , so whatever you figure out this year for your growing situation will be ballpark for next year.

My hops are getting close but not ready yet. I use them soley for flavour and aroma and use hops with a known AA for bittering.

Well, i talked to the head of our analytical lab, and he didn't undertstand what "alpha acid" is or how to test for it.

He said he'd test it, though, if i can get him more information and it doesn't take too much time. :rockin:

So, is there a more technical name for alpha acid? Does anyone have any more information on how it would be tested in a lab??

http://www.biocompare.com/technical...Beer-from-Applied-Biosystems-47MDS-Sciex.html



I don't need a life, beer is my life!

DeathBrewer:

Have your lab guy reference the ASBC (American Society of Brewing Chemist) Methods of Analyses under "Hops". I think "Hops - (Method) 6" is what he needs. It can be done via a spectrophotometer or conductometry.

Dr Malt