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Aspera

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I recently purchased a pound of Styrian Goldings hops. After placing the order, I noticed that the AA content was about 2% lower than usual. I was wondering if the aromatic qualities will also be affected or if this is in any way an indicator of poor quality. I'm not especially concerned about the bittering properties but would like to know if the hops are otherwise different from what I usually use.
 
Not an indicator of poor quality, just of a different crop most likely. Are they European or New Zealand Styrian? The NZ Styrians I've see are about 2.9% AAU, while the European I recently got are over 5%. Just use a proportionally larger amount than you usually do and it should be fine.
 
They are true Styrian Goldings (not from Austria, but from Slovenia). The AA is about 3.2%. Is it even truthful to to call a hop Styrian Golding's if it is from NZ. Isn't that just another Fuggle cultivar?
 
Is it even truthful to to call a hop Styrian Golding's if it is from NZ. Isn't that just another Fuggle cultivar?
I agree, but I've seen Styrian Goldings (NZ) and the AA% is roughly 2.9%. Your 3.2% from Slovenia could be from a first or second year crop, or maybe it's just a bad year for that particular region. Just use about 50% more than you normally do and they should be just fine.
 
Is there a formula to work out how to correct for different values?

The hops i need are

45.00 gm Northern Brewer [8.50%] (60 min) Hops 42.1 IBU
15.00 gm Goldings, East Kent [5.00%] (15 min) Hops 4.1 IBU
10.00 gm Goldings, East Kent [5.00%] (5 min) Hops 1.1 IBU

and the ones i bought are

Northern Brewer [5.5%]
Goldings, East Kent [4.5%]
 
It's a direct proportion so 45gm @ 8.5% = x gm @ 5.5%. You need ~70gm of NB @ 5.5%. Using the same formula, your 15 min addition of EKG would be ~17gm and your 5 min addition would be ~11gm.
 
For flavoring and finishing hops, the AAU doesn't matter. You're talking about fractions of IBUs in that example. I wouldn't change them at all.

Bittering hops are different- you want to "match" up the IBUs as above.
 
For flavoring and finishing hops, the AAU doesn't matter. You're talking about fractions of IBUs in that example. I wouldn't change them at all.
Kybert asked about a formula, though, so I was showing how it would work. Can't disagree in this particular instance, but it would matter if there was a bigger AAU% difference even on finishing hops, e.g., 5.5% v. 2.6%.
 
It's a direct proportion so 45gm @ 8.5% = x gm @ 5.5%. You need ~70gm of NB @ 5.5%. Using the same formula, your 15 min addition of EKG would be ~17gm and your 5 min addition would be ~11gm.

For completness, and future reference, ive added the formula to work this out, it may be usefull in the future.

PHP:
(max % - min %) 
---------------  x  original weight   =   additional hops required (weight) 
      max % 

so: 

   8.5% - 5.5% 
   -----------   x  45g 
       8.5% 

     3 
=  ----- x  45g 
    8.5 


=  0.35  x  45g 
        
=  15.88g 

= new hops weight required = 45 + 15.88 = 60.88g

I think thats correct!
 
Going back to the original question: year-to-year AA% varies a great deal more than aromatic oil levels.
 
For completness, and future reference, ive added the formula to work this out, it may be usefull in the future.

PHP Code:
(max % - min %)
--------------- x original weight = additional hops required (weight)
max %

so:

8.5% - 5.5%
----------- x 45g
8.5%

3
= ----- x 45g
8.5


= 0.35 x 45g

= 15.88g

= new hops weight required = 45 + 15.88 = 60.88g
I think thats correct!

You are calculating how much LESS acid there is in the lower acidity hops, when you should be calculating how much MORE acid there is in the higher acidity hops.

However, I can see how that mistake could be made.

But, to check your formula, take easy numbers, such as:
- 10% AA and 5% AA
- 10 g 10% AA hops
- now substitute that with the amount of 5% AA hops required and it is easy to see that it is
(10 / 5) * 10g and not ((10 - 5) / 10) * 10g

What a way to start off HTB posting ;)

p.s. The above formula assumes the actual amount of hop material does not affect the IBUs, when in practice it most likely does...
 
Going back to the original question: year-to-year AA% varies a great deal more than aromatic oil levels.

Thanks, I was hoping that you would say that. I although these are a great bittering hop, that is not what they are really meant for.
 
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