What's normal?

[RickBeer]

I've been brewing extract recipes for 20 months now. Almost every recipe I have says to add x ounces of y hops. Only one recipe says "XX HBU".

I completely understand that if a recipe calls for 7.5 HBU, and the AA is 5%, I need 1.5 ounces.

Now that I'm making some of these recipes for the third time, I've noted that the AA% for some of the hops has changed pretty noticeably since the last time I bought them. I buy from the same source, and nearly all the time I buy the exact same hops (I have done things like buy the German version of an American hop with a slightly higher AA%).

Examples of changes:

Northern - was 9.9 now 10.5%
Hallertaur - was 4.7 now 2.7%
Fuggle - was 5.3 now 4.5%
Kent Golding - was 5.8 now 7.2%

I'm adding the hops as per the recipes, which in every case has me start with 2.5 gallons of water, steep my grains, add my LME (6 - 7 pounds), bring to a boil, and then begin adding hops. I understand that the SG of that 2.5 gallons + steep + LME is much higher than recommended for maximum hop utilization, and therefore it is likely that I'm sacrificing efficiency - but that's the recipes and I like the results.

When I look at a bittering hop in a recipe, like a clone of Bell's Best Brown, in QBrew (which may be assuming perfect efficiency), the IBU's change pretty noticeably when the Cascade goes from 4% to 6.9%.

Given that the recipes do not list any HBU (does list IBU), I have no idea what AA% hops they used. I found a chart here: http://www.beeradvocate.com/beer/101/hops/ but it has ranges that are fairly wide PLUS some of what I've bought is outside the range.

So, what do you do when a recipe says 1.5 oz of X? Do you play with QBrew or another tool and work backwards? And lower the SG of the wort, add the hops, then add the rest of the LME later?

Just curious, to be honest I have no idea if I had two versions of Bell's Best Brown with different AA% if I would notice (I will compare when it's ready).

[John Sand]

Generally I just use the spec amount. You could run your known AA through a calculator. But bitterness not precise science. I think if my bittering hops were much lower than expected, I should add more, and especially, less if much higher. I just haven't, and it seems okay.

[Dawg LB Steve]

Found some info in HBT, search Does BU=IBU. Basically it states:
1 ounce of 1 AA hops = 1 HBU
If you work it up on QBrew and play with the weights to see where the IBU come up consistent across different AA%. The AA% on hop crops change from year to year and from grower to grower.
Your Hallertuer is a big change, but its not that high in AA% that I don't think would be a huge difference in bittering.

[mashani]

Your never going to be totally accurate anyways, because even though your package says nnAA% that was only what it was when they packaged it. Depending on how old they are and storage conditions, that number could be quite a bit higher then it really is. So I'd personally not stress about it too much except to guess to the lower or higher side of the bitterness scale you prefer.

[DaYooper]

Because a lot of times the recipe doesnt list the alphas, if I like it the first time I just adjust the IBUs for subsequent batches. Normally all I care about is the bittering addition unless the flavor adds a good chunk in which case many times I just add more bittering. Flavor and aroma are a bit more difficult as they dont necessarily correlate to the alphas so I tend to keep them about the same, maybe a little more depending on the age. If you are looking at kit or LHBS recipes, remember that they probably dont bother to go back and adjust their recipe for each batch of hops they get. Most will simply list the hops in the acceptable breed's range, and probably only purchase them if they are in that range. Another thing to note are the recipes online. You almost always see hop additions listed in 1/4 oz increments, so that says something right there. Nobody works up a random recipe and says "I think 0.43276oz will be a good flavor addition."

[Inkleg]

I do like John. If it says use 1.5oz of hop X, that what I put in. I don't pay much if any attention to AAs.

Also AAs will change with each growing season.

[RickBeer]

So basically everyone just puts in the stated amount of hops, with the exception of the hop farmer who adjusts future recipes if he liked it the first time.

What I expected, just this time I saw such a large difference.

I should have put that I know they change each season, and by supplier. More was getting at what people do when it's different than it's been or not specified.

[Kealia]

Because I use BeerSmith when crafting recipes, I get the AAUs for each addition and replicate that when I rebrew. Meaning, if the AA% of the hops I pick up are less than what I used the last time, I will adjust the recipe to use more hops to hit the same AAU target.

[Rebel_B]

I may make slight adjustments to a bittering (60 minute) addition to stay on the projected IBUs for a recipe, but I will always stay with the same volumes for any other additions. Yeah, seems like every time I get hops at my LHBS the % is different than the previous visit. Means they are going through their inventory, nothing is lingering in the freezer for too long a time.

[DaYooper]

Because I use BeerSmith when crafting recipes, I get the AAUs for each addition and replicate that when I rebrew. Meaning, if the AA% of the hops I pick up are less than what I used the last time, I will adjust the recipe to use more hops to hit the same AAU target.

Yeah, BeerSmith makes it so easy to do this I will usually do it during a boring conference call while printing out the recipe. Would I do this if I didnt have so many pointless conference calls? I dunno. But I do so I do.