adjust hops for 5 gal boil

[ohcoger]

I am making a brewers best kit of IPA and it says to start with 2.5 gals I would like to use 5 gals the bittering hops are 2 oz cascade 7.9% and 1 oz columbus 14.2% the aroma hops 1 oz cascade 7.5%. I would like to know the math for I can adjust.

 

[Grinder12000]

I'll let others help with the math but congratulations on doing a full boil on an IPA and not a partial boil. It will be MUCH MUCH better. I think IPAs should be discouraged with partial boils as you will not get the full utilization of the hops! (only half actually).

Best help would be to post the recipe! as written in the instructions

 

[ohcoger]

Ingredients

Fermentables
6.6 lb light lme
1 lb golden dme

Grains
1 lb crystal 40l
8 oz victory

Hops bittering
2 oz cascade aa 7.9%
1 oz Columbus aa 14.2%

hops Aroma 5 min
1 oz cascade aa 7.5%

Yeast
Sachet

 

[Grinder12000]

Does it say when you should add the aroma hops?? 10 minutes? 15 minutes something like that?

With a partial boil this will be a pretty weak IPA - maybe not even up to APA yet.

Full boil you get a pretty nice IPA

With a 2.5 gallon boil you will have about 45 IBU'S which is a number used to tell how much hops will be in the brew - with a full boil it goes to 85ish.

NOW of course you can not go on one number and you have to look at the malt and balance and so forth.

I can't see the partial boil being . . .very good - pretty darn malty.

If I were you - heck - if you want a good IPA keep it the same

 

[Grinder12000]

Here is the deal - with a 2.5 gallon boil you will get your 85 IBUs but then you will dilute the wort with another 2.5 gallons so the total IBUs will be cut in half.

NORMALLY this is not a big deal in maltier beers but with hoppy brews it really cuts into hop bitterness.

 

[Arkador]

Correct me if i am wrong... but his question is to stay true to the recipe, what does he need to change in his hop addition...

I believe going from 2.5g to 5g boil only requires 80% the hops due to better utilization..
so,
Hops bittering
2 oz cascade aa 7.9%
1 oz Columbus aa 14.2%
1 oz cascade aa 7.5%
becomes
1.6oz Cascade
.8oz Columbus
.8oz cascade

 

[Grinder12000]

Using Beer Tools you are upping the IBU's by about 25 with

1.6oz Cascade
.8oz Columbus
.8oz cascade

so the brew will be a totally different beer won't it?

Not arguing - just looking at tools AND - correct me if i am wrong.

 

[Arkador]

Grinder12000, if you have beertools, how about throwing his 2.5g oil recipe in, and change it to a 5g boil, and list the hop changes.

I need to buy brewing software......

 

[Grinder12000]

If you cut the hops in half you get basically the same IBU when comparing the 3 gallon boil to a 6 gallon boil.

NOW - with that said I PERSONALLY would be nervous about cutting my hops in half because . . .I've never done that. Seems like a lot. Trust is tough.

Also Beer Smith is a free download and it only costs like $20 anyway - GREAT software. I use it a lot for strike temps and all sorts of nifty things.

1.063 SG
45 IBU