have I got it wrong???? hop utilization.

So I'm a little confused,

I attempted to copy the avant garde-american pale ale recipe from gordon strong's brewing better beer into beer smith I ended up with est OG of 1.057, 18.3 EBC(9.3 SRM),6.5 ABV which was all pretty close to the recipe being 1.060 OG, 10 SRM, and 6.3 ABV. The one that's confusing me is the IBU's 45 in gordon's recipe and it came in at 79.7 in beersmith i've adjusted all the AA's to the same as in the book which helped but the only way i could get it down to 45 was to play with the hop utilization factor and take it down to 57% am I on the wrong path or have I got it totally wrong  :-[ any help would be awesome

cheers

I don't have the book in front of me right how (I am at work), but I believe that Gordon uses the Rager formula in his recipes for calculating the IBUs.  If you are using Tinseth, this may be part of the issue.

When I copy a recipe into BeerSmith, I usually ignore the printed IBU for the recipe.  The author's utilization and process may give a totally different bitterness perception than what I get for the same calculated IBU value.  Further, I know when I brew something of a certain calculated IBU on my system how that may taste from doing perception calculations using established commercial beers and close clones. 

When entering a recipe from a book, what I do is match the hops and timing of addition. Then for each hop addition, I match the AAU (Alpha Acid Units) which is the (AA% in the recipe * wt of hop added / AA% of that same hop that I have on hand).  This will give me the amount of hops which will deliver the same concentration of AA for each addition.

Usually, I am entering the recipe at the same batch size as what is printed with a generic equipment profile representing the efficiency of the recipe.  I can then scale the recipe to my standard equipment profile for the system I will use to brew it.

+1 to check for Rager vs. Tinseth.  Also verify you have selected the correct option for each addition:  Boil, Mash, FWH, etc.

cool so i tried the rager tinseth thing and it didnt change anything unless ive done that wrong too FML. but im looking at the recipe and its got 126 gms of hops seems like alot to me for only 45 ibu's and a 19 liter batch. im really just after the best way to copy a recipe into beersmith i suppose heres the recipe see what you guys can come up with



2.90 kg Pale Malt, Maris Otter (5.9 EBC) Grain 1 64.7 %
0.45 kg Vienna Malt (6.9 EBC) Grain 2 10.0 %
0.34 kg Caramel/Crystal Malt - 40L (78.8 EBC) Grain 3 7.6 %
0.23 kg Wheat Malt, Ger (3.9 EBC) Grain 4 5.1 %
0.11 kg Caramel/Crystal Malt - 80L (157.6 EBC) Grain 5 2.5 %
28.00 g Amarillo [8.00 %] - First Wort 60.0 min Hop 6 30.5 IBUs
0.45 kg Sugar, Table (Sucrose) (2.0 EBC) Sugar 7 10.1 %
14.00 g Columbus (Tomahawk) [14.00 %] - Boil 20.0 min Hop 8 14.7 IBUs
14.00 g Columbus (Tomahawk) [14.00 %] - Boil 15.0 min Hop 9 12.0 IBUs
14.00 g Columbus (Tomahawk) [14.00 %] - Boil 10.0 min Hop 10 8.8 IBUs
14.00 g Simcoe [12.00 %] - Boil 5.0 min Hop 11 4.1 IBUs
28.00 g Amarillo [8.00 %] - Boil 2.0 min Hop 12 2.3 IBUs
14.00 g Simcoe [12.00 %] - Boil 0.0 min Hop 13 0.0 IBUs


Gravity, Alcohol Content and Color

Est Original Gravity: 1.057 SG
Est Final Gravity: 1.009 SG
Estimated Alcohol by Vol: 6.3 %
Bitterness: 72.4 IBUs
Est Color: 18.2 EBC

how does gordon get 45 ibu's

fifthpinned06 said:

cool so i tried the rager tinseth thing and it didnt change anything unless ive done that wrong too FML.

Click to expand...

I went back through several iterations of the recipe, including one that was for BYO. Each came up between 60 and 75 IBU, but each is pretty consistent in stating about 45. Without asking him I can't be sure, but I would believe that he had it lab tested. Gordon is pretty thorough like that.

So, I'd make the recipe as-is.

cool ill give it a crack then cheers guys