[davidgzach]

Got my analysis back from Alpha Analytics the other day.  Alpha at 8.7% and Beta at 6.3%.  Pretty psyched.

I can't make out the HSI or Hop Storage Index rating.  I know Cascades are at the low end of the storage spectrum but what does .23 mean? 

Dave

[kramerog]

Got my analysis back from Alpha Analytics the other day.  Alpha at 8.7% and Beta at 6.3%.  Pretty psyched.

I can't make out the HSI or Hop Storage Index rating.  I know Cascades are at the low end of the storage spectrum but what does .23 mean? 

Dave

Means 23% assuming there are not units provided.  In other words, only 23% of the alpha remains.

[davidgzach]

After what?  6 months refrigerated?  Frozen? 

[denny]

HSI is calculated based on 6 months storage at 68F.  For instance, a hop that starts at 10% alpha with a HSI of .250 will have 7.5% after 6 months at 68F.  However, storing those same hops at 28F for 6 months will leave you with 9% AA.

[davidgzach]

HSI is calculated based on 6 months storage at 68F.  For instance, a hop that starts at 10% alpha with a HSI of .250 will have 7.5% after 6 months at 68F.  However, storing those same hops at 28F for 6 months will leave you with 9% AA.

Thanks Denny.  What is the math to get to 9% after 6 months at 28F?  Or is that a standard 10% reduction across the board?

[denny]

HSI is calculated based on 6 months storage at 68F.  For instance, a hop that starts at 10% alpha with a HSI of .250 will have 7.5% after 6 months at 68F.  However, storing those same hops at 28F for 6 months will leave you with 9% AA.

Thanks Denny.  What is the math to get to 9% after 6 months at 28F?  Or is that a standard 10% reduction across the board?

They didn't show us the math at Hop and Brew school.  Just the final numbers.  But I'd guess it would be the same across the board.

[davidgzach]

HSI is calculated based on 6 months storage at 68F.  For instance, a hop that starts at 10% alpha with a HSI of .250 will have 7.5% after 6 months at 68F.  However, storing those same hops at 28F for 6 months will leave you with 9% AA.

Thanks Denny.  What is the math to get to 9% after 6 months at 28F?  Or is that a standard 10% reduction across the board?

They didn't show us the math at Hop and Brew school.  Just the final numbers.  But I'd guess it would be the same across the board.

Makes sense-10% across the board at 28F.

[denny]

Makes sense-10% across the board at 28F.

The other thing to keep in mind is that it varies by variety and harvest conditions.  So it's only applicable if you have the hops analyzed like you did.

[davidgzach]

Makes sense-10% across the board at 28F.

The other thing to keep in mind is that it varies by variety and harvest conditions.  So it's only applicable if you have the hops analyzed like you did.

Good info, thanks.  Got a kick out of having my own hops analyzed.  Now I'm not guessing at IBUs!

[S. cerevisiae]

If you decide to pony up the dough for another round of analysis next year, you should spring for the basic oil content test as well. The oil content rating is more useful than the alpha/beta ratings when it comes late hopping.   I ponied up the dough for the "Hop Profile Package," which includes the brewing values (alpha, beta, and HSI), oil content percentage (a.k.a. milliliters of oil per 100 grams of hops), and the volatile oil analysis (gas chromatograph analysis of the volatile oils).  The only other value that I would have liked to have obtained was co-humulone as a percentage of the alpha acids.