Hop Calculation Problem...Tasty's SNPA-inspired IPA

[Roguejim]

Thanks to some forum members here, I listened to an old Jamil Show wherein Tasty gave out his SNCA-inspired IPA recipe. I wrote the info down, then plugged it into Promash. Here it is, minus the hopback and dry hop additions. My question is below the recipe:

Tasty

A ProMash Recipe Report

Recipe Specifics
----------------

Batch Size (Gal): 12.00 Wort Size (Gal): 12.00
Total Grain (Lbs): 34.00
Anticipated OG: 1.066 Plato: 16.05
Anticipated SRM: 13.6
Anticipated IBU: 75.0
Brewhouse Efficiency: 65 %
Wort Boil Time: 60 Minutes

Pre-Boil Amounts
----------------

Evaporation Rate: 15.00 Percent Per Hour
Pre-Boil Wort Size: 14.12 Gal
Pre-Boil Gravity: 1.056 SG 13.76 Plato

Formulas Used
-------------

Brewhouse Efficiency and Predicted Gravity based on Method #1, Potential Used.
Final Gravity Calculation Based on Points.
Hard Value of Sucrose applied. Value for recipe: 46.2100 ppppg
Yield Type used in Gravity Prediction: Fine Grind Dry Basis.

Color Formula Used: Morey
Hop IBU Formula Used: Tinseth
Tinseth Concentration Factor: 1.30

Additional Utilization Used For Plug Hops: 2 %
Additional Utilization Used For Pellet Hops: 10 %
Additional Utilization Used For Mash Hoppings: -30 %


Grain/Extract/Sugar

% Amount Name Origin Potential SRM
-----------------------------------------------------------------------------
82.4 28.00 lbs. Pale Malt(2-row) America 1.036 2
5.9 2.00 lbs. Cara-Pils Dextrine Malt 1.033 2
5.9 2.00 lbs. Crystal 60L America 1.034 60
2.9 1.00 lbs. Crystal 120L America 1.033 120
2.9 1.00 lbs. Munich Malt Germany 1.037 8

Potential represented as SG per pound per gallon.


Hops

Amount Name Form Alpha IBU Boil Time
-----------------------------------------------------------------------------
1.50 oz. Chinook Pellet 11.00 18.2 Mash H
1.00 oz. Chinook Pellet 11.00 17.3 60 min.
4.00 oz. Centennial Pellet 9.90 31.0 15 min.
4.00 oz. Cascade Pellet 6.70 8.4 5 min.


I entered everything per the recipe, i.e., AAUs, efficiency, amounts...The only difference right off is I use Tinseth, and I believe Tasty uses Rager. This brings me to the 60 minute Chinook addition. According to the show, total IBUs for the recipe should be ~80, and the 60 minute addition should provide 32.5 IBUs. As you can see, I'm only getting 17.3 IBUs from that addition. The other hop IBU additions (15...5 minute) are just slightly higher than Tasty's numbers, which I attribute to me using Tinseth. But the fact that my 60 minute addition is so far off, yet my total IBUs is within 5 IBUs of Tasty's recipe has me puzzled. Any ideas you guys might have would be appreciated.

One other thing is that I don't know how accurate the IBUs for the MH addition is. I don't recall an IBUs number being given. I used the same hop quantity from the show, same AAUs, and -30% for MHing in my System Settings, which I believe is the same setting that Tasty uses. Still, the 60 minute addition is what I'm focused on now. What did I miss?

[Charlie]

I pugged the numbers into BeerSmith 2 (current). The OG and SRM are right on, but the IBU is 56.3.

My numbers are:

1.50 oz. Chinook Pellet 12.40, 5.2, Mash H
1.00 oz. Chinook Pellet 12.40, 17.3, 60 min.
4.00 oz. Centennial Pellet 10.0, 27.7, 15 min.
4.00 oz. Cascade Pellet 5.50, 6.1, 5 min.

Something is wonked!

Charlie (is also using Tinseth)

[Roguejim]

Charlie,
Your AAUs are not per the recipe...they're higher. So, your total IBUs would be even lower still had you adjusted your AAUs per the recipe. Anyway, I'm stumped. That 60 minute Chinook addition is the main problem as far as I can tell. I may have to go back and relisten to the show. Heck, I wasn't even drinkin'!

[Charlie]

I calculated it based on the hops I've got in stock. My Chinook and Centennial is higher, Cascade is lower. Regardless the numbers don't come close to 75 IBU! But! I get 73 if I use 2 oz of Chinook at 60 min.

Which show is this on?

Let me know what you find out.

Charlie

[Roguejim]

Here's the show. If you have time give it a listen.
http://thebrewingnetwork.com/shows/The- ... w-07-02-07

[Charlie]

I just listened to the show, and there's two corrections: Tasty's doing a 90 minute boil, and there's the 4 oz of cascade in the hopback (he also said that it's a sort-of SN Celebration clone). That doesn't pick up a whole lot of IBU, so I don't know what's going on.

Charlie

[Roguejim]

I just listened to the show, and there's two corrections: Tasty's doing a 90 minute boil, and there's the 4 oz of cascade in the hopback (he also said that it's a sort-of SN Celebration clone). That doesn't pick up a whole lot of IBU, so I don't know what's going on.

Charlie

The first hop addition isn't until 60 minutes, so the 90 minute total boil is irrelevant in that regard. And like you said, next to no IBU contribution from the hopback, which is why I left it out. Yeah...I screwed up the Subject line with "SNPA"...oh well. Thanks for giving the show a listen. Now I know the recipe is off, somehow...

[TastyMcD]

Here's my IPA recipe. It's my attempt at cloning the 1999 version of Sierra's Celebration Ale. If you're of the belief that mash hopping is a waste of hops (I guess you'd also have to believe first wort hopping does nothing as well.), move them to the boil. Tasty.