Adjusting amount of hops.

[JonathanMSE]

I'm going to brew a Greg Hughes' Amarillo single hop.

The recipe calls for Amarillo with 5% alpha acid. With the following additions.

54g - 70 mins
27g - 15 mins
27g - 5 mins
83g - 0 mins

giving 40 IBU.


However, the Amarillo I have has an alpha acid of 8.6% if I use the same additions it gives about 69 IBU which is really not the same beer.

I was thinking use fewer hops at the start of the boil and more towards the end of the boil to keep the bitterness around 40 and compensating for any lost aroma. Would that work or wouldn't still change the beer?

 

[Clint]

You need to use some software. There's some on this forum in the "calculator " section. Have play you'll soon get the hang,you can manually input hop aau %.

 

[JonathanMSE]

You need to use some software. There's some on this forum in the "calculator " section. Have play you'll soon get the hang,you can manually input hop aau %.

Oh yeah, its not so much the alpha that worries me, I can easily adjust it to get the same IBU.
But if I change the hops for bitterness will it change the aroma of the later additions?

 

[The-Engineer-That-Brews]

I was thinking use fewer hops at the start of the boil and more towards the end of the boil to keep the bitterness around 40 and compensating for any lost aroma. Would that work or wouldn't still change the beer?

Hmmm... I can see where you are coming from there.
I think I'd leave the proportion of late to early hops the same though, because IMHO if the alpha acid of the hops is stronger then the aroma is probably stronger too... (but I'm no expert)

 

[Clint]

Most of the bitterness will come from the first two additions, which in return will give not very much aroma..
As your hops are nearly double % I'd do all the bitterness on the first addition then all the rest at the end.

 

[JonathanMSE]

So, I think I'll do the following

29g at 70 (down from 54g)
15g at 15 (down from 27g)
27g at 5 (same as before)
90g at 0 (up from 83g)

Bitterness is 40 IBU, same as the recipe, and the extra hops at flame out should compensate for any lost aroma/taste from hops added at 15 mins.

 

[Hoppyland]

I would go for adjusting hops for bitterness early in the boil, and for flavour stick to very late additions, if not "whirlpool". I will take a lot of convincing that a hop addition in the last 5 mins of the boil is going to produce a noticeable difference in flavour compared to a post-boil whirlpool or hop steep.

 

[Gerryjo]

Just adjust with a simple calculator is what I do.
54g * 5 = 270/8.6= 31.4g @ 70 mins
27g * 5 = 135/8.6 = 15.7 @ 15 mins
27g * 5 = 135/8.6 = 15.7 @ 5 mins
83g * 5 = 415/8.6 = 48.2 @ 0 mins

This will give keep your IBU's in check with the recipe as all you are doing is using the AA% to recalculate your new weight to the value required.

 

[abacab666]

Beersmith lets you change the alpha of your hops and recalculate the ibu, so you can adjust accordingly

 

[Gerryjo]

Beersmith lets you change the alpha of your hops and recalculate the ibu, so you can adjust accordingly

Handy but good that you can also do it on the fly as a lot of users don't use beersmith although I do have mobile version 3 but prefer Brewers Friend for syncing from the laptop which also allows you the same advantage.

 

[JonathanMSE]

Beersmith lets you change the alpha of your hops and recalculate the ibu, so you can adjust accordingly

I've got the Brewer's friend desktop app which has seemingly disappeared into the ether and isn't available for download anymore. I use that to adjust AA. But what it doesn't help with is taste and aroma. Which is where I came unstuck.

In any case following advice and my own messing around I decided to keep all additions the same, except for at the start of the boil which I reduced to 29g.

I got 45.2 IBU rather than the 40 the recipe suggests. I can live with that. Just waiting for the wort to chill and then I can pitch the yeast and whack it in the fridge.
Target OG was 1.049 I hit 1.052 (temp adjusted) so I'm rather pleased with that!