i don’t really understand what this number is but understand how to determine it.
i am just plugging an iipa into beersmith trying to figure out the first brewing recipe.
it’s got a projected og of 1.081, 60.4 ibu and is a 4 gallon batch. the bitterness ratio, according to beersmith, is .748. is this good or bad?
i don’t know how to interpret this number. i’m just barely into the green bar on the ibu slider, if that makes sense. i’m not looking for palate wrecking numbers. am i on the right track?
Yes, you’re on the right track. bu:gu is bitterness units to gravity units. It is the IBU (60.4) divided by the gravity as points (81).
If you are going for a beer that is not very bitter for the style, keeping the ratio under 1 is a good move. If you want it to be super bitter, 1+ is the way to go.
I don’t use it much, but it can be a useful measure for tweaking recipes.
I just find using a bu:gu ratio is a better way to get in the right ballpark for bitterness when I’m formulating a recipe. This way if you’re brewing a beer that’s either small or big for a particular style you keep in the right ballpark for bitterness.
One thing with IIPA’s is that they generally end up bone dry and are so highly hopped that the hops end up filling out the mouthfeel a bit. If you use a real low hopping rate for the style like you are, then you may want to add some carapils or flaked barley to make sure it doesn’t end up too thin.
It also depends on hnw quickly you can chill your wort once the boil ends. Prolonged rest at high temps still allows some alpha acid isomerization to occur. An example of this would be trying to chill a 5+ gallon BK in your sink or tub–it’s going to take >30 minutes.
I do 10 gallon batches and use a 50 ft copper IC to chill the wort; I find it gets down to ambient temps within 15-20 minutes. Yet, through experience, I’ve found that I still need to keep the projected IBU’s (using BeerSmith software) at the very low end of the range in order to end up with beer that is not overly bitter for the style. YMMV.
Maybe the emails below will be of some interest. They are from Matt Van Wyk of Oakshire Brewing in Eugene, Oregon, and Vinnie Cilurzo of Russian River Brewing. I asked them what percent of the total IBUs they try to derive from the bittering addition in an AIPA. I also put the question to Mike “Tasty” McDole, and Denny Conn. (I don’t think they would mind my sharing their info here). Draw your own conclusions. 8)
Hi Jim-
It depends. It depends on how bitter you want the beer and how hop flavored and aromatic you want it. That, in many senses is up to personal taste. If you want to follow a 1:1 BU:GU ration, a 1.066 beer would be 66:66 or 66 BUs for a beer with 66 gravity units.
In my opinion, IBUs are not important and I wish they didn’t appear on our bottle. Experiment with different levels and see what you like better. at 5-10 gallons per batch, you can do several experiments. Good luck!
Matt
Jim,
Thanks for the email, no, we don’t have a set percent of BU’s we want to get out of the first hop addition. It really varies from recipe to recipe. Since we make so many IPA’s, I mix it up so some get a bunch of bitterness from the initial addition, while others get a bunch of bittering from the middle addition or even the last addition and thus those beers have a bigger hop flavor and aroma.
I hope this helps,
Vinnie
Jim,
I try to get 2/3 of the IBUs in the last 20 minutes of the boil (and post boil if there’s a flameout addition). So the answer to your question is I try to limit the 60 minute addition to 1/3 of the total IBU’s.
Tasty
Jim,
…I start by deciding on a rough BU:GU ratio for the beer. Then I add enough FWH to get the flavor I want…usually 1-2 oz. Then I add in enough 60 hops to get within 10-20 IBU of the total I’m shooting for. Since I use FWH, I seldom use a 20 min. addition, so the rest of the IBU come from 15 min. or less additions.
thanks fellas. i’ve upped my hops a bit but am still just under 1. i’m trying to find a solid balance. i have a bunch of amarillo whole leaf to use up and am using them for this recipe. i don’t want to go too bitter like i did a couple years back with a bunch of simcoe(third batch ever).
Just keep in mind that it’s totally subjective. You have to decide for yourself what ratio is best for your tastes. The best way to do that is to brew a recipe repeatedly and change the ratio each time til you get what you want. Then use that as a guide in other recipes.
Also bear in mind that were you to do the actual assay to determine the IBU level, it would likely be something like 60-120% of what you’re calculating. Even when brewing the same recipe, batch-to-batch variations of 10-20% are common.