Which IBU formula does the BJCP use?

[jm]

I searched around a little on the BJCP site and through the actual PDF and couldn't find the answer. Does anyone what formula would most closely match up to the BJCP (I'm guessing Rager since it seems the most widely used)? Most of the formulae calculate to within a few IBUs of each other except for Garetz which on the recipe I converted turned a 30 IBU beer into a 20 IBU beer. So if they're using Garetz I'd have an APA that was pretty far out of style instead of an APA that was at the low end of the style.

[codewritinfool]

To answer your original question, IBU=IBU. There is no formula.

In reading the body of your post, though, I see what you're really asking.

You're asking what formula you should use on your equipment to land in the IBU range for a given style. I'm sure it depends on your setup to some extent. Jamil uses Rager. So do I, not that that is worth anything.

If you want to know for sure, choose one and send your beer to a lab. White Labs performs this service, but I don't know what it costs.

[jm]

You're asking what formula you should use on your equipment to land in the IBU range for a given style. I'm sure it depends on your setup to some extent. Jamil uses Rager. So do I, not that that is worth anything.

Right. The question in the subject is not really what I was asking about...me dumb.

I'm curious how the BJCP ended up with their IBU ranges (did they send a bunch of examples to a lab or ask the breweries or what?) and how does a brewer use the available formulae to put their beers in that range.

Now that I've had a couple and read your response I'm pretty sure any of them are good enough. From the few I tried only Garetz produced drastically different results so as long I don't use that I'm probably going to be close enough.

If you want to know for sure, choose one and send your beer to a lab. White Labs performs this service, but I don't know what it costs.

Neat. In February they do the Big QC Day and you can get two beers tested for $129.

[mabrungard]

I doubt that BJCP has any bittering formula included in their association with bitterness shown in the style guidelines. I'd say that the bitterness range listed in the guidelines was deciphered through lab testing and via educated palates.

But given that, I'd say that the Rager formula might be more an indicator of what a beer was intended to replicate since it has been so widely used. The Garetz formula is a joke, I would never use it. Tinseth's formula has been proven to be most accurate, but then you have to wonder if the author of the recipe that you're replicating used Rager or Tinseth. I've found that I'm better off using Rager for an initial assessment of a recipe and then adjusting from there.

[Chupa LaHomebrew]

It's most likely based on the stats the brewery provides, which can be either measured by a lab, or calculated using one of many formulas (and there can be a big difference depending on the beer, brewery, and their calculation techniques). I would take them with a grain of salt.

[BDawg]

[edit - for the new guys in the thread, Welcome! and yes, I'm a BJCP judge]
There is no "standard" formula "blessed" by the BJCP.

That said, I've always taught Rager in my BJCP classes because it's widely used and easy to memorize. I've also sort of become accustomed to the bitterness levels that I get when I formulate using it, so whether it is truly accurate or not, I generally can count on the bitterness levels it comes up with and they seem to generally match what my palate finds as published levels in commercial beers that actually publish their IBU levels.

In other words, as an example, I like my Am. Pale Ales best when the Rager formula comes up right around 40 IBUs. Same way with Am. IPA's (65). I really don't care about the actual number, but I find that I like my results when Rager says its gonna hit these numbers.

Hope this makes sense.

[jm]

[edit - for the new guys in the thread, Welcome! and yes, I'm a BJCP judge]
There is no "standard" formula "blessed" by the BJCP.

That said, I've always taught Rager in my BJCP classes because it's widely used and easy to memorize. I've also sort of become accustomed to the bitterness levels that I get when I formulate using it, so whether it is truly accurate or not, I generally can count on the bitterness levels it comes up with and they seem to generally match what my palate finds as published levels in commercial beers that actually publish their IBU levels.

In other words, as an example, I like my Am. Pale Ales best when the Rager formula comes up right around 40 IBUs. Same way with Am. IPA's (65). I really don't care about the actual number, but I find that I like my results when Rager says its gonna hit these numbers.

Hope this makes sense.

Makes sense and matches up with my thinking after more drinking and thinking on the subject. Though we (naturally) differ a bit in our preferred IBUs per style; I like a gentler APA and a more aggressive IPA.

If I can remember it I'm going to send in a couple of bottles for the WL 2011 QC day just to see how accurately my recipes, software and palette are according to reality. Has anyone sent their beers in for the past QC days? Did you think it was worth it?

[dmtaylor]

I'll give you the quick skinny as I see it.

IBUs are a value measured in a laboratory. The truth is, they are what they are, and the formulae are all just an approximation.

That being said, Rager is the most popular (dammit) largely because (dammit) Jamil uses it and advocates it.

HOWEVER, Tinseth is the most accurate of them all, and is the one I have always used for that simple fact.

All the others like Garetz, HBU, etc., are all subpar and I don't know a ton of people that use those.

The very best thing a homebrewer can do is to pick one formula, and stick with it for life. You might not be able to know the real IBUs that would be measured in a laboratory, but as a measuring stick and frame of reference for you, and ONLY you, it will be extremely helpful, and you must stay consistent.

All that being said, if you pick anything other than Tinseth, you are just plain less than as accurate as possible.

So I guess what I'm trying to say is, if you want to get as close as reasonably possible to real values specified by the BJCP, then you really need to get the values measured in a lab first of all, but otherwise, Tinseth is the way to go. And I have done a LOT of looking into this.