I have an IPA under way ATM. I did the following to a Morgans IPA kit:
Added 1 kit of Coopers real ale (29 IBUs)
1 kilo LDME
Dry hopped with 20g POR and 20g Cascade for the last 3 days of secondary.
Authentic India Pale Ale
Ohhkay.
So you've used goldings with a higher AA% than the recipe, which means that these hops will impart more bitterness to the beer. However, you have also added the kit to the beginning of the boil, which will increase the gravity of the boil, and thus reduce your AA utilisation. So I'd say you're probably reasonably close to the recipe, and it shouldn't be a disaster by any means.
There are a few concepts you need to understand here to work out what's going on.
AA% is the Alpha Acid percentage of the hop. The higher the percentage, the more bitterness it can impart to your wort.
% utilisation. The percentage of the AA in the hops that is actually isomerised during the boil and disolves in the wort.
Gravity of the wort. The higher the gravity of the wort, the less alpha acid can be dissolved in it. See the Hops FAQ. The Tinseth method is the one most often used. There are calculators available to do this for you. e.g. http://www.rooftopbrew.net/ibu.php
There is also another factor which is that there seems to be an upper limit of bitterness that can be either dissolved or perceived in your beer. So as you add more hops, the utilisation goes down.
So you've used goldings with a higher AA% than the recipe, which means that these hops will impart more bitterness to the beer. However, you have also added the kit to the beginning of the boil, which will increase the gravity of the boil, and thus reduce your AA utilisation. So I'd say you're probably reasonably close to the recipe, and it shouldn't be a disaster by any means.
There are a few concepts you need to understand here to work out what's going on.
AA% is the Alpha Acid percentage of the hop. The higher the percentage, the more bitterness it can impart to your wort.
% utilisation. The percentage of the AA in the hops that is actually isomerised during the boil and disolves in the wort.
Gravity of the wort. The higher the gravity of the wort, the less alpha acid can be dissolved in it. See the Hops FAQ. The Tinseth method is the one most often used. There are calculators available to do this for you. e.g. http://www.rooftopbrew.net/ibu.php
There is also another factor which is that there seems to be an upper limit of bitterness that can be either dissolved or perceived in your beer. So as you add more hops, the utilisation goes down.
w00t!
Thanks for all the replies. I didn't think this was going to be that bad; I'd just like to learn from my mistakes.
The links provided have all been really useful too; bookmarked and will print and read the Norm Pyle's page for reference.
I'm having a go at the wheat beer with honey tonight.
Now my biggest problem is a shortage of bottles
Cheers,
Chris
The links provided have all been really useful too; bookmarked and will print and read the Norm Pyle's page for reference.
I'm having a go at the wheat beer with honey tonight.
Now my biggest problem is a shortage of bottles
Cheers,
Chris